POLYMER COMPOSITES FOR FRICTION AND SEALING UNITS OF TECHNOLOGICAL EQUIPMENT

Full text

JELGAVA, LATVIA
SEPTEMBER 20-22, 2023

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Organized by Institute of Polymer Materials
Faculty of Materials Science and Applied Chemistry, Riga Technical University
Scientific Committee
Prof. Mārtiņš Kalniņš, Dr. Jānis Zicāns, Prof. Remo Merijs-Meri (Latvia), Prof.Andres
Krumme, Dr. Vitali Sõritski (Estonia), Prof. Juozas Vidas Gražulevičius, Prof. Ričardas
Makuška, Prof. Arūnas Ramanavičius (Lithuania)
Organizing Committee
Prof. Remo Merijs-Meri, Asoc. Prof. Agnese Ābele, Dr. Janis Zicans, MSc Ivan Bochkov,
PhD. Stud. Madara Ziganova (Latvia)
THANK
FOR OUR SPONSORs

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TABLE OF CONTENTS
Programme
3
Plenary and oral presentations
3
List of poster presentations
6
The conference abstracts
12

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PROGAMME
(CONFERENCE VENUE- The Latvian University of Life Sciences and Technologies (LBTU) at the
Jelgava Castle)
September 20
19.00-21.00
Welcome Drink- Pilsetas elpa, Pasta sala 1, Jelgava, LV-3001
September 21
9.30-10.00
Registration- LBTU, Lielā iela 2, Jelgava, LV-3001
10.00-10.15
Opening -LBTU, Lielā iela 2, Jelgava, LV-3001
ORAL SESSION 1. Chairman: Prof. Remo Merijs-Meri
10.15-10.45
PLENARY:
INNOVATION FUND – NATIONAL RESEARCH PROGRAM FOR APPLIED RESEARCH
DEVELOPMENT
A. Anspoks
Institute of Solid State Physics, University of Latvia, 8 Kengaraga Street, Riga, LV-1063, Latvia
10.45-11.00
INVESTIGATION OF RAW MATERIAL OF LITHUANIAN AND WESTERN UKRAINIAN
FOLK HOME TEXTILE
E. Kumpikaitė1, D. Milašienė1, O. Nykorak2, L. Herus 2, T. Kutsyr2, Ž. Rukuižienė1, E.
Nenartavičiūtė 3
1Department of Production Engineering, Kaunas University of Technology, Kaunas, Lithuania
2Department of Folk Art, Institute of Ethnology of National Academy of Sciences of Ukraine, Lviv, Ukraine
3Department of Exhibitions and Expositions, Open Air Museum of Lithuania, Rumšiškės, Lithuania
11.00-11.15
SYNTHESIS OF THERMOPLASTIC CELLULOSE ESTERS IN NOVEL IONIC LIQUID
N. Savale1, E. Tarasova1, I. Krasnou1, M. Kudryashova2, I. Reile3, A. Krumme1
1Department of Materials and Environmental Technology, Tallinn University of Technology, Tallinn, Estonia
2Department of Chemistry and Biotechnology, Tallinn University of Technology, Tallinn, Estonia
3National Institute of Chemical Physics and Biophysics, Tallinn, Estonia
11.15-11.45
Coffee break

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ORAL SESSION 2. Chairman: Dr.sc.ing., Natalja Savest
11.45-12.15
PLENARY:
MOLECULARLY IMPRINTED POLYMER NANOGELS - SYNTHETIC PEPTIDE
ANTIBODIES FOR BIOMEDICAL THERAPY AND DIAGNOSTICS
K. Haupt
CNRS Laboratory for Enzyme and Cell Engineering, Université de Technologie de Compiègne, Rue du Docteur
Schweitzer, 60203 Compiègne, France
12.15-12.30
DEVELOMPENT OF NEW TRIPLET-TRIPLET ANNIHILATION PHENOMENA BASED
MATERIALS FOR OPTOELECTRONICS
A. Bucinskas1, A. Petrenko2, P. Arsenyan2, T-L. Chiu3, O. Bezvikonnyi1, D. Volyniuk1, J. V.
Grazulevicius1
1Department of Polymer Chemistry and Technology, Kaunas University of Technology, Kaunas, Lithuania
2Latvian Institute of Organic Synthesis, Riga, Latvia
3Yuan Ze University, Taoyuan City, Taiwan
12.30-12.45
IONIC LIQUIDS RECYCLING
I. Krasnou, A. Krumme
Department of Materials and Environmental Technology, Tallinn University of Technology, Tallinn, Estonia
12.45-13.00
DIRECT INJECTION MOLDING WITH OPTIMISED SCREWS AND ANALYTICS FOR
ASSESSING THE MIXING QUALITY
G. Japins1, J. Pape2, R.-U. Giesen1, H.-P. Heim1
1 Institute of Material Engineering, Polymer Engineering, University of Kassel, Kassel, Germany
2 PAPE GmbH, Porta Westfalica, Germany
13.00-14.00
Lunch
14.00-15.00
POSTER SESSION WITH COFFEE, REFRESFMENTS, SNACKS
ORAL SESSION 3. Chairman: Dr.sc.ing. U. Cabulis
15.00-15.15
CHARACTERIZATION OF WOVEN ELECTROMAGNETIC SHIELDING
THERMOPLASTIC-FIBER COMPOSITES COMPARED TO NON-WOVEN
ELECTROMAGNETIC SHIELDING CONCEPTS
T. Elsesser 1; A. Ries 1; H.-P. Heim2
1Bielefeld Institute for Applied Materials Research, Bielefeld University of Applied Sciences, Bielefeld,
Germany
2Institute of Materials Engineering, University of Kassel, Kassel, Germany
15.15-15.30
POLYMER COMPOSITES FOR FRICTION AND SEALING UNITS OF TECHNOLOGICAL
EQUIPMENT
О. Kabat, V. Sytar, J. Zicans, R. Merijs-Meri (Zoom presentation)
1Ukrainian State University of Chemical Technology, Dnipro-City, Ukraine
2Institute of Polymer Materials, Riga Technical University, Riga, Latvia

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15.30-15.45
SYNTHESIS OF ACTIVATED CHARCOAL / FERRIC FERROCYANIDE HYBRID
COMPOSITE MATERIALS FOR REMOVAL OF RADIOACTIVE CESIUM FROM WATER
K. A. Jefimova1,5, U. Eismonts2, A. Ščerbicka3, K. Saleniece2, A. Actiņš1, R. Stūrmane4, A.
Kons1, I. Reinholds1,5, M. Bērtiņš1, A. Vīksna1, G. Ķizāne5, A. Grīnbergs5
1Faculty of Chemistry, University of Latvia, Riga, Latvia
2Faculty of Medicine, University of Latvia, Riga, Latvia
3Agenskalns State Gymnasium, Riga, Latvia
4Riga State Gymnasium No. 1, Riga, Latvia
5Institute of Chemical Physics, University of Latvia, Riga, Latvia
15.45-16.00
HIGH PERFORMANCE EMI SHIELDING POLYMER COMPOSITES
S. Gaidukovs, M. Bleija, O. Platnieks
Institute of Polymer Materials, Faculty of Materials Science and Applied Chemistry, Riga Technical University, Latvia
16.00-16.30
Coffee break
17.50
Bus to gala dinner venue (Saules iela 2, Brankas, Cenu pagasts, LV-3042)
18.00-23.00
Gala dinner
September 22
ORAL SESSION 4. Chairman: Prof. Ricardas Makuska
9.00-9.30
PLENARY:
A CONTRIBUTION TO CIRCULARITY OF PLASTICS: THERMOPLASTICS
LIGHTWEIGHT MATERIALS, BIO-BASED PLASTICS AND MATERIAL-FLOW-
ORIENTED RECYCLING
Maik Feldmann
Head of Business Unit Polymer Applications at Fraunhofer Institute for Microstructure of Materials and Systems IMWS -
Halle/Germany
Head of Polymer Processing Fraunhofer Pilot Plant Center for Polymer Synthesis and Processing PAZ -
Schkopau/Germany
Professor for Polymer Processing - University of Applied Science in Merseburg/ Germany
9.30-9.45
POLYMER BRUSH COATED UPCONVERTING NANOPARTICLES WITH IMPROVED
COLLOIDAL STABILITY AND CELLULAR LABELING
V. Klimkevičius1,2, G. Jarockyte2, K. Bolgova1, A. Katelnikovas1 and V. Karabanovas2
1Institute of Chemistry, Vilnius University, Naugarduko 24, LT-03225 Vilnius, Lithuania
2Biomedical Physics Laboratory of National Cancer Institute, Baublio 3B, LT-08406, Vilnius, Lithuania
9.45-10.00
DESIGN AND SYNTHESIS OF THE DONOR-ACCEPTOR-DONOR TADF MOLECULES
FOR APPLICATION IN OLED
N. S. M. Jamel1, L. Skhirtladze2, M.K. A. Wahab1, K. L. Woon3, A. A. Hussein4, J. V.
Grazulevicius2 and A. Ariffin1,2*
1Department of Chemistry, Faculty of Science, Universiti Malaya, 50603 Kuala Lumpur, Malaysia.
2Department of Polymer Chemistry and Technology, Faculty of Chemical Technology, Kaunas
University of Technology, Lithuania.
3Department of Physics, Faculty of Science, Universiti Malaya, 50603 Kuala Lumpur, Malaysia
4Department of Medical Laboratory Science Komar University of Science and Technology
Sulaymania, 46001, Iraq
10.00-10.30
Coffee break

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ORAL SESSION 5. Chairman: Prof. Juozas Vidas Grazulevicius
10.30-11.00
PLENARY:
THERMORESPONSIVE POLYMERS: FROM SYNTHESIS TO APPLICATIONS
R. Rutkaite
Department of Polymer Chemistry and Technology, Kaunas University of Technology, Kaunas, Lithuania
11.00-11.15
CORRELATIONS BETWEEN THERMOHYGROSCOPIC INFLUENCES AND
MECHANICAL PROPERTIES IN WOODTEXTILE COMPOSITES (WTC)
C.L. von Boyneburgk1, J.C. Zarges1, H.-P.Heim1
Institute of Material Engineering, Polymer Engineering, University of Kassel, Kassel, Germany
11.15- 11.30
MOLECULARLY IMPRINTED POLYMER AS A SELECTIVE RECOGNITION ELEMENT
FOR DETECTION OF AZOXYSTROBIN IN AQUEOUS MEDIA
V. B. C. Nguyen, J. Reut, V. Syritski
Department of Materials and Environmental Technology, Tallinn University of Technology, Tallinn, Estonia
11.30-11.45
UV CURING COATINGS ON NATURAL NAILS
Z. Grigale-Sorocina, I. Birks
Kinetics Nail Systems, Ltd
11.45-12.00
POLYURETHANES FOR GLASS SEALANTS – EVOLUTION FROM FOSSIL-BASED TO
RENEWABLE FEEDSTOCK
J. Jaunbergs
SIA TENACHEM, member of the SOUDAL GROUP
12.00-12.30
Closing session
12.30-13.30
Lunch
13.45
Excursion
POSTER SESSION
September 21, 14.00-15.00
No.
Poster
1.
PROCESSING OF BIOCOMPOSITES CONTAINING HEMP SEED HULL WASTE
J. Bendoraitiene, G. Kuzminskaite, V. Perepecajava, R. Jakubauskas, D. Liudvinaviciūte, L.
Peciulyte, R. Rutkaite
Department of Polymer Chemistry and Technology, Kaunas University of Technology, Kaunas, Lithuania
2.
INVESTIGATION OF DIFFERENT NATURE POLYMERIC 3D PRINTED HEELS FATIGUE
BEHAVIOUR
E. Gelažienė, D. Milašienė
Department of Production Engineering, Kaunas University of Technology, Kaunas, Lithuania
3.
STUDIES OF POSSIBILITIES OF SYNTHETIC FIBRES SURFACE MODIFICATION WITH
CuXSe
D. Milašienė1, O. Belukhina1, R. Ivanauskas2
1Department of Production Engineering, Kaunas University of Technology, Kaunas, Lithuania
2Department of Physical and Inorganic Chemistry, Kaunas University of Technology, Kaunas, Lithuania

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4.
DEVELOPMENT OF A BIOBASED COMPATIBILIZER AND ITS EFFECT ON RAPESEED
FIBRES STRUCTURE AND PROPERTIES OF RECYCLED POLYMER COMPOSITES
Z. Iesalniece1,2, R. Bērziņa1, R. Bērziņš1, A. Ābele1, J. Zicāns1, R. Merijs-Meri1
1Institute of Polymer Materials, Faculty of Materials Sciences and Applied Chemistry, Riga Technical University, Riga, Latvia
2 Ltd. SAKRET, Rumbula, Latvia
5.
EFFECT OF CARBOXYLIC ACIDS AND TANNIC ACID AS COMPATIBILIZER ON
MECHANICAL PROPERTIES OF RECYCLED POLYOLEFIN COMPOSITES WITH NATURAL
FIBERS
A. Ābele, R. Bērziņa, I. Bočkovs, S. Motrončiks, J. Zicāns, R. Merijs-Meri, R. Bērziņš
Institute of Polymer Materials, Faculty of Materials Sciences and Applied Chemistry, Riga Technical University, Riga, Latvia
6.
PREPARATION OF SILANE-TREATED LIGNOCELLULOSIC FIBRES FOR POLYMER
COMPOSITES
S. Motrončiks, R. Bērziņš, A. Ābele, R. Merijs-Meri
Institute of Polymer Materials, Faculty of Materials Sciences and Applied Chemistry, Riga Technical University, Riga, Latvia
7.
MECHANICAL BEHAVIOR OF THE LIGNOCELLULOSIC FIBER-REINFORCED RECYCLED
PP/PE COMPOSITES
I. Bočkovs, M. Žiganova, A. Ābele, R. Merijs-Meri
Institute of Polymer Materials, Faculty of Materials Sciences and Applied Chemistry, Riga Technical University, Riga, Latvia
8.
ACCELERATED WEATHERING TESTING EFFECTS ON THE PROPERTIES OF POLY(3-
HYDROXYBUTYRATE-CO-3-HYDROXYVALERATE AND ITS BIOCOMPOSITES WITH
RAPESEED MICROFIBER
M.Žiganova, R. Merijs-Meri, J. Zicāns, A. Ābele, I. Bockovs, T. Ivanova
Institute of Polymer Materials, Faculty of Materials Sciences and Applied Chemistry, Riga Technical University, Riga, Latvia
9.
CHANGES IN RECYCLED PLASTICS AND POTENTIAL OF MICROPLASTIC FORMATION
DUE TO UV IRRADIATION
L. O. Vasiļjevs1,2, E. Kuka1, D. Cirule1, I. Andersone1, B. Andersons1
1Laboratory of Wood Biodegradation and Protection, Latvian State Institute of Wood Chemistry, Riga, Latvia
2 Faculty of Chemistry, University of Latvia, Riga, Latvia
10.
EFFECTS OF MODIFICATION CONDITIONS ON STARCH ESTERS PROPERTIES
L. Peciulyte, J. Luneckas, J. Bendoraitiene, R. Rutkaite
Department of Polymer Chemistry and Technology, Kaunas University of Technology, Kaunas, Lithuania
11.
ACTIVE PAPER COATINGS CONTAINING ESSENTIAL OILS AND THEIR COMPONENTS
V. Navikaite-Snipaitiene1, K. Spirikavice1, R. Rutkaite1, E. Galkauskaite1, J. Siugzdaite2, E.
Beatrice Grigonyte2
1Department of Polymer Chemistry and Technology, Kaunas University of Technology, Kaunas, Lithuania
2Department of Veterinary Pathobiology, Lithuanian University of Health Science, Kaunas, Lithuania
12.
EFFECT OF DIFFERENT MODIFIED CARDANOL COMPOUNDS ON THE MECHANICAL AND
CLIMATIC RESISTANCE PROPERTIES OF THE MATERIAL
R. Bērziņš1, A. Ābele1, J. Zicāns1, R. Merijs-Meri1, O. Kabat2, V. Sytar2
1Institute of Polymer Materials, Faculty of Materials Sciences and Applied Chemistry, Riga Technical University, Riga, Latvia
2Department of Innovation Engineering, Ukrainian State University of Chemical Technology, Dnipro-City,Ukraine
13.
EFFECT OF SILYL-TERMINATED CARDANOL AND DIFFERENT FILLERS ON CURING
DYNAMICS AND MECHANICAL PROPERTIES OF POLYETHER-BASED SILYL-
TERMINATED PREPOLYMER
R. Bērziņš1, A. Ābele1, J. Zicāns1, R. Merijs-Meri1, O. Kabat2, V. Sytar2
1Institute of Polymer Materials, Faculty of Materials Sciences and Applied Chemistry, Riga Technical University, Riga, Latvia
2Department of Innovation Engineering, Ukrainian State University of Chemical Technology, Dnipro-City,Ukraine
14.
INFLUENCE OF LONG-TERM STORAGE AND UV LIGTH EXPOSURE ON RIGID PU FOAMS’
CHARACTERISTICS
B. Sture, V. Yakushin, U.Cabulis
Polymer Laboratory, Latvian State Institute of Wood Chemistry, Riga, Latvia

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15.
ELECTROSPUN FIBROUS MEMBRANES FOR TATTOO WOUND CARE
Z. Zelca1, K. Pavlovica1, A. Reinis2
1 Institute of Design technology, Faculty of Materials Science and Applied Chemistry, Riga Technical University, Riga, Latvia;
2 Department of Biology and Microbiology, Riga Stradins University, Riga, Latvia
16.
THE EXTRACTED BIRCH OUTER BARK AS A FILLER FOR WOOD-PLASTIC COMPOSITE
G. Shulga1, B. Neiberte1, A. Verovkins1, J. Rizhikovs2, A. Paze2, S. Vitolina1, T. Betkers1
Laboratory of Lignin Chemistry1 and Biorefinery Laboratory2, Latvian State Institute of Wood Chemistry, Riga, Latvia
17.
OPTIMIZATION OF MICROENCAPSULATION OF ISOPHORONE DIISOCYANATE IN
POLYUREA SHELL
L. Pastarnokienė, T. Kochanė, E. Potapov, R. Makuška
Department of Polymer Chemistry, Faculty of Chemistry and Geosciences, Vilnius University, Vilnius, Lithuania
18.
DEVELOPMENTS OF POLYURETHANE CRYOGENIC INSULATION MODIFIED WITH PHASE
CHANGE MATERIALS
U. Cabulis, L. Vevere, B. Sture, V. Yakushin
Polymer Laboratory, Latvian State Institute of Wood Chemistry, Riga, Latvia
19.
PHLOROGLUCINOL-BASED SHAPE-MEMORY POLYMERS
A. Navaruckienė, A. Pabricaitė, J. Ostrauskaitė
Department of Polymer Chemistry and Technology, Kaunas University of Technology, Kaunas, Lithuania
20.
PROTEASE PRODUCTION FROM E. COLI BL21(DE3)-PET32A-ASP AND ITS APPLICATION
IN LEATHER DEHAIRING
R. Biškauskaitė1, W.-C. Lee2, V. Valeika1
1Department of Polymer Chemistry and Technology, Kaunas University of Technology, Kaunas, Lithuania
2 Department of Chemical Engineering, National Chung Cheng University, Chia-Yi, Taiwan R.O.C.
21.
SYNTHESIS AND STUDY OF AZO GROUP CONTAINING POLYMERS
S. Vardanyan1, 2, N.Durgaryan1, 2, J.Gražulevičius2
1Department of Organic chemistry of Yerevan State University, Yerevan, Armenia
2Department of Polymer Chemistry and Technology, Kaunas University of Technology, Kaunas, Lithuania
22
MEASUREMENT OF THERMAL CONDUCTIVITY OF CARBON FIBER REINFORCED
LAMINATES BY TRANSIENT PLANE SOURCE METHOD
S. Tarasovs, A. Aniskevich
Institute for Mechanics of Materials, University of Latvia, Riga, Latvia
23.
THERMORESPONSIVE PROPERTIES OF ACENAPHTHYLENE LABELLED CHITOSAN
GRAFT POLY(N-ISOPROPYLACRYLAMIDE) COPOLYMERS
M.Babelyte1, R.Rutkaite1, V. Navikaite-Snipaitiene1, E. Morkvenaite1, V. Samaryk2
1Department of Polymer Chemistry and Technology, Kaunas University of Technology, Kaunas, Lithuania
2 Department of Organic Chemistry, Lviv Polytechnic National University, Lviv, Ukraine
24.
NEW HOLE-TRANSPORTING MATERIALS FOR ORGANIC OPTOELECTRONICS BASED ON
P-PHENYLENEDIAMINE SKELETON FUNCTIONALIZED WITH SULFUR-CONTAINING
MOIETIES
S.Sargsyan1, M. Stanitska2, 3, M.Ghasemi2, R. Keruckiene2, D.Volyniuk2, N.A. Durgaryan1, J.
V.Grazulevičius2
1 Department of Organic Chemistry, Yerevan State University, Alex Manoogian St., 1, Yerevan 0025
2 Department of Polymer Chemistry and Technology, Kaunas University of Technology, K. Baršausko st. 59, LT-51423, Kaunas,
Lithuania
3 Department of Organic Chemistry, Ivan Franko National University of Lviv, Kyryla i Mefodiya st. 6, Lviv, Ukraine
25.
DIBENZOTHIOPHENE AND TRIPHENYLAMINE DERIVATIVES AS EMITTERS IN
ELECTROLUMINESCENCE DEVICES AND OPTICAL OXYGEN SENSORS
M.Ghasemi1, M. Mahmoudi1, D. Guedeika1, K.Leitonas1, J.Simokaitiene1, A. Dabuliene1,
A.Panchenko2, B. F. Minaev2, D. Volyniuk1, J.V. Grazulevicius1
1Department of Polymer Chemistry and Technology, Kaunas University of Technology, Kaunas, Lithuania
2Department of Chemistry and Nanomaterials Science, Bohdan Khmelnytsky National University, Cherkasy, Ukraine

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26..
SIMPLICITY AND EFFICIENCY: A HOST-FREE ORGANIC LIGHT-EMITTING DIODE
ATTAINITG 4.6% OF EXTERNAL QUANTUM EFFICIENCY WITH DERIVATIVE OF 1H-1,2,3-
TRIAZOLE AS BLUE EMISSIVE LAYER
M. Stanitska1,2, N. Pokhodylo2, R. Lytvyn2, E. Urbonas1, D. Volyniuk1, K. Ivaniuk3, Pavlo Stakhira3,
R.Keruckiene1, M.Obushak2, J. V. Grazulevicius1
1Department of Polymer Chemistry and Technology, Kaunas University of Technology, Kaunas, Lithuania
2Department of Organic Chemistry, Ivan Franko National University of Lviv, Lviv, Ukraine
3Department of electronic Engineering, Lviv Polytechnic University, Lviv, Ukraine
27.
MECHANOCHROMIC LUMINESCENCE, AGGREGATION-INDUCED EMISSION
ENHANCEMENT AND THERMALLY ACTIVATED DELAYED FLUORESCENCE OF
DERIVATIVES OF PHENOTHIAZINE AND DIFFERENTLY MODIFIED 3,5-DICYANOPYRIDINE
L.Volyniuk1*, P.Arsenyan2, M.Stanitska1, O. Bezvikonnyi1, A. Lazauskas3, D. Volyniuk1, J.V.
Grazulevicius1
1Department of Polymer Chemistry and Technology, Kaunas University of Technology, Kaunas, Lithuania
2Latvian Institute of Organic Synthesis, Riga,Latvia
3Institute of Materials Science, Kaunas University of Technology, Kaunas, Lithuania
28.
CARBAZOLE-BENZOPHENONE DERIVATIVES AS HOSTS FOR SOLUTION PROCESSABLE
GREEN TADF OLED DEVICES
D. Blaževičius1, R. Beresnevičiūtė1, G. Kručaitė1, D. Tavgenienė1, S. Grigalevičius1, M. R. Nagar2,
C. T. Hao2, J.-H. Jou2, K. Kumar3
1Department of Polymer Chemistry and Technology, Kaunas University of Technology, Kaunas, Lithuania
2Department of Materials Science and Engineering, National Tsing Hua University, Taiwan
3School of Chemical Sciences, Indian Institute of Technology, Mandi, HP, India
29.
IN THE SEARCH OF NEW METAL-FREE EMITTERS FOR OLEDs EMPLOYING RPA
TECHNOLOGIES
A. Bucinskas1, M. Stanitska1 T. Krilavicius2, J. Šiaulys1, R. Juozaitiene2, B. Zhyhun2, A. Kristutis1,
A. Paulauskaitė-Taraseviciene3, J. V. Grazulevicius1
1Department of Polymer Chemistry and Technology, Kaunas University of Technology, Kaunas, Lithuania
2Faculty of Informatics, Vytautas Magnus University, Kaunas, Lithuania
3Artificial Intelligence Centre, Kaunas University of Technology, Kaunas, Lithuania
30.
PEROVSKITE SOLAR CELLS WITH MONOLAYER MODIFIED PTAA AND ITS APPLICATION
TO ALL-PEROVSKITE TANDEM SOLAR CELLS
D. Tavgenienė1, H. Bi2, Y. Fujiwara2, Ch. Ding2, S. R. Sahamir2, Y. Sanehira2, A. K. Baranwal2, K.
Takeshi2, G. Shi2, G. Kapil2, Z. Zhang2, L. Wang2, T. Bessho3, H. Segawa3, S. Grigalevicius1, Q.
Shen2, S. Hayase2
1Department of Polymer Chemistry and Technology, Kaunas University of Technology, Kaunas, Lithuania
2i-Powered Energy System Research Center, The University of Electro-Communications, Tokyo, Japan
3Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, Japan
31.
NEW MONO-MOLECULAR HTL LAYER FOR WIDE BANDGAP LEAD PEROVSKITE SOLAR
CELLS
R. Beresnevičiūtė1, H. Bi2,3, J.Liu2, Z. Zhang2, L.Wang2, D. Tavgenienė1, G. Kapil2, Chao Ding3,
A. K. Baranwal2, S. R. Sahamir2, Y. Sanehira2, H. Segawa4, S.Grigalevičius1, Q. Shen2,3,
S.Hayase2,3
1Department of Polymer Chemistry and Technology, Kaunas University of Technology, Kaunas, Lithuania
2i-Powered Energy System Research Center, The University of Electro-Communications, Chofu, Tokyo, Japan
3Graduate School of Informatics and Engineering, The University of Electro-Communications, Chofu, Tokyo, Japan
4Research Center for Advanced Science and Technology, The University of Tokyo, Meguro-ku, Tokyo, Japan
32.
POLYMERIC ORGANIC LIGHT-EMITTING DIODES BASED ON EMITTERS EXHIBITING
THROUGH-SPACE CHARGE-TRANSFER TYPE THERMALLY ACTIVATED DELAYED
FLUORESCENCE
D. Volyniuk, M. Ghasemi,V. Andruleviciene,G. Belousov,I.Vasilenko,S.Kostjuk, J.V.Grazulevicius
Department of Polymer Chemistry and Technology, Kaunas University of Technology, Kaunas, Lithuania

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33.
BLUE AGGREGATION-INDUCED EMISSION MOLECULES CONSISTING OF
PHENYLSULFONYL-BENZENE CORE AND TRIPHENYLETHENE-CARBAZOLE MOIETY FOF
HIGHLY EFFICIENT OLEDS
G. Krucaite1, S. Grigalevicius1, M.-J. Lin2, J.-S. Hong 2, C.-H. Chang2
1Department of Polymer Chemistry and Technology, Kaunas University of Technology, Lithuania
2Department of Electrical Engineering, Yuan Ze University, Taiwan
34.
RAMAN ANALYSIS OF CuxS THIN FILMS DEPOSITED ON the SURFACE OF
POLYPROPYLENE
E. Paluckiene1, M. Gilić2,3, N. Petrasauskiene1
1Department of Physical and Inorganic Chemistry, Kaunas University of Technology, Kaunas, Lithuania
2Institute of Experimental Physics, Freie Universität Berlin, Berlin, Germany
3Institute of Physics Belgrade, Belgrade, Serbia
35.
ANALYSIS OF CuxS THIN FILM DEPOSITED ON SURFACE OF POLYAMIDE – RAMAN
SPECTROSCOPY
N. Petrasauskiene1, M. Gilić2, E.Paluckiene1
1Department of Physical and Inorganic Chemistry, Kaunas University of Technology, Kaunas, Lithuania
2Institute of Experimental Physics, Freie Universität Berlin, Berlin, Germany
3Institute of Physics Belgrade, Belgrade, Serbia
36.
DIBLOCK COPOLYMERS OF METHACRYLOYLOXYETHYL PHOSPHORYLCHOLINE AND
DOPAMINE METHACRYLAMIDE: SYNTHESIS AND SOLUTION PROPERTIES
M. Jurkūnas, A. Šimkutė, R. Makuška
Faculty of Chemistry and Geosciences, Vilnius University, Vilnius, Lithuania
37.
BIOBASED POLYESTER COMPOSITES FOR PACKAGING APPLICATIONS
J. Bitenieks, R. Merijs-Meri, J. Zicans, T. Ivanova, R. Bērziņa
Institute of Polymer Materials, Riga Technical University, Riga, Latvia
38.
PVA THERMOELECTRIC NANOCOMPOSITE CONTAINING MWCNT-Sb2Te3 AND MWCNT-
Bi2Se3 HYBRID FILLERS
J. Bitenieks1, R. Merijs-Meri1, J. Zicans1, T. Ivanova1, J. Andzane2, K. Buks2, D. Erts2
1Institute of Polymer Materials, Riga Technical University, Riga, Latvia
2Institute of Chemical Physics, University of Latvia, Riga, Latvia
39.
PRE-LOVED BIOTEXILE SUBTITLE DESIGNING WITH UNRECYCLABLE TEXTILE FIBRES
S. Polakova1,2, M. Bērziņa1, R. Merijs-Meri2, A. Bernava2, R. Bērziņa2, J. Bitenieks2
1Studio Sarmite, 1-5 Schwedlerstraße, Frankfurt am Main, HE, 60314, Germany
2Institute of Polymer Materials, Faculty of Materials Sciences and Applied Chemistry, Riga Technical University, 3 Paula Valdena
street, Riga, LV-1048, Latvia
40.
XRD and SEM/EDS STUDIES OF COBALT SULFIDE LAYERS ON POLYAMIDE 6
K. Vaičiukynaitė1, R.Ivanauskas1, S. Žalenkienė1
1Department of Physical and Inorganic Chemistry of Kaunas University of Technology, Lithuania
41.
SCRATCH RESISTANCE OF HOT STAMPED MULTILAYER STRUCTURES VS ADHESIVE
NATURE AND THICKNESS
S. Shubaum1, V. Grigaliūnas2, P. Narmontas2, J. Donelienė3, J. Ulbikas3,4, E. Fataraitė-
Urboniene1,3
1Department of Production Engineering, Faculty of Mechanical Engineering and Design, Kaunas University of Technology,
Kaunas, Lithuania
2 Institute of Materials Science, Kaunas University of Technology, Kaunas, Lithuania
3Applied Research Institute for Prospective Technologies, Vilnius, Lithuania
4JSC “Modernios E-Technologijos”, Vilnius, Lithuania
42.
ELECTROSPUN MATERIALS IN TRIBOELECTRIC SERIES
N. Savest1, I.Krasnou1, A. Krumme1, I. Dobryden2, K. Håkansson2, J.Edberg3
1Laboratory of Biopolymer Technology, Tallinn University of Technology, Tallinn, Estonia
2 Bioeconomy and Health, RISE Research Institutes of Sweden, Drottning Kristinas väg 61, Stockholm, SE-114 28 Sweden
3 Printed-, Bio- and Organic Electronics, RISE Research Institutes of Sweden, Bredgatan 35, Norrköping, SE-602 21 Sweden

11
43.
FEATURES OF THE PROCESSING THE POLYMER MIXTURE WASTE BASED ON GLASS-
FILLED POLYAMIDE
S. V. Prystynskyi1,2, V. P. Plavan1
1Department of Chemical Technologies and Resource Saving, Kyiv National University of Technologies and Design, Ukraine
2LLC Kostal Ukraine, Pereyaslav, Kyiv Region, Ukraine
44.
POLYAMIDES MODIFIED BY COMPOUNDS WITH SILOXANE GROUPS
V. Sytar1, О. Kabat1, A.Ābele2, R. Bērziņš2
1Ukrainian State University of Chemical Technology, Dnipro-City, Ukraine
2Institute of Polymer Materials, Riga Technical University, Riga, Latvia
45.
DEVELOPMENT OF BIOBINDERS WITH IMPROVED PERFORMANCE AND ANTIOXIDANT
PROPERTIES BY PARTIAL SUBSTITUTION OF BITUMEN WITH LIGNIN
V.Haritonovs1, R. Merijs-Meri2, J. Zicans2, V. Straupe1, V. Zabolotnii3, M. Tamosiunas3, R. Viter3,
A. Arnautovs4
1Department of Roads and Bridges, Riga Technical University, Kipsalas street 6a, Riga, LV-1048, Latvia
2Department of Polymer Materials Technology, Riga Technical University, Paula Valdena street 3, Riga, LV-1048, Latvia
3Institute of Atomic Physics and Spectroscopy, University of Latvia, Jelgavas street 3, Riga, LV-1004, Latvia
4Institute of Mechanics of Materials, University of Latvia, Aizkraukles street 23, Riga, LV-1006, Latvia

12
INNOVATION FUND – NATIONAL RESEARCH PROGRAM FOR
APPLIED RESEARCH DEVELOPMENT
Andris Anspoks
Institute of Solid State Physics, University of Latvia, 8 Kengaraga Street, Riga, LV-1063, Latvia
andris.anspoks@cfi.lu.lv
In this talk I will summarise current activities in applied research development through national
research programs in Latvia. The innovation fund is geared towards innovation development
and pools the efforts of leading national institutions. This research program develops skills in
mutual collaboration to solve existing market needs and create opportunities for new emerging
industries. I will focus on the challenges and success factors that we have learned from our
current development. The current topics of this program cover a wide range of materials and
applications: from polymers to oxides, from photonics to packaging. I will also present possible
future roadmaps that can multiply the impact of the current results.
Acknowledgement
This research is funded by the Latvian Council of Science, project “Smart Materials, Photonics, Technologies and
Engineering Ecosystem” project No VPP-EM-FOTONIKA-2022/1-0001

13
INVESTIGATION OF RAW MATERIAL OF LITHUANIAN AND
WESTERN UKRAINIAN FOLK HOME TEXTILE
Egle Kumpikaitė1, Daiva Milašienė1, Olena Nykorak2, Lyudmyla Herus2,
Tetiana Kutsyr 2, Žaneta Rukuižienė 1, Erika Nenartavičiūtė 3
1Department of Production Engineering, Kaunas University of Technology, Kaunas, Lithuania
2Department of Folk Art, Institute of Ethnology of National Academy of Sciences of Ukraine, Lviv, Ukraine
3Department of Exhibitions and Expositions, Open Air Museum of Lithuania, Rumšiškės, Lithuania
Lithuanian and Western Ukrainian home textile is one of the most important and beautiful part
of tangible heritage in both countries. The main objects of this heritage are folk towels and
bedspreads. One of the main structural parameters of folk textile is its raw material.
Home-made or rarer bought material was the most often used for folk Lithuanian and Western
Ukrainian towels. Home-made materials were linen, hemp, tows, etc. In the end of the 19th
century cotton yarns started to be used. Warp of folk towels was usually made from linen or
cotton yarns and from tow yarns for household towels. Weft often was from linen, hemp or tow.
Hemp was rare used in Lithuania; it was more common in Ukrainian towels. Often the warp was
of bleached linen or white cotton and weft was of natural colour linen yarns. Sometimes the
linen weft was lightly dyed with oak’s bark; the pattern of such towels was more expressed in
the background of white warp.
Raw material of folk bedspreads was more diverse in both countries. Warp the most often was
cotton, linen, hemp (in Ukraine) or tow (for everyday bedspreads), but the variety of weft raw
material was higher. Apart of the same composition as the warp, wool and since the 4th decade
of the 20th century silk (in Lithuania) was used for the weft of bedspreads. Also the variety of
bedspreads colours was more diverse in comparison to folk towels.
Thus, it can be seen that the tendencies of raw material in Lithuania and Western Ukraine were
similar, but also had some unique features. It is important results for manufacturers of
reconstructions of folk textile in both countries.
Acknowledgement
This investigation was supported by the Lithuanian Research Council and the Ministry of Education and Science
of Ukraine [grant number in Lithuania S-LU-22-5, in Ukraine M/21-2022].

14
SYNTHESIS OF THERMOPLASTIC CELLULOSE ESTERS IN NOVEL
IONIC LIQUID
Nutan Savale1, Elvira Tarasova1, Illia Krasnou1, Marina Kudryashova2,
Indrek Reile3, Andres Krumme1
1Department of Materials and Environmental Technology, Tallinn University of Technology, Tallinn, Estonia
2Department of Chemistry and Biotechnology, Tallinn University of Technology, Tallinn, Estonia
3National Institute of Chemical Physics and Biophysics, Tallinn, Estonia
The production of thermoplastic polymers, primarily derived from nonrenewable sources like
oil, is leading to environmental issues such as pollution and depletion of natural resources.
Consequently, there is an urgent requirement to identify sustainable alternatives. Cellulose, an
abundant and carbon-neutral renewable material, holds great potential as a raw material in
diverse industries including food, paper, textiles, cosmetics, pharmaceuticals, and biomaterials.
By means of esterification, cellulose can be chemically modified and transformed into valuable
derivatives with desirable properties like thermoplasticity. Ionic liquids (ILs) have emerged as
highly promising sustainable solvents for dissolving cellulose, enabling the production of
homogenous functionalized cellulose esters with numerous industrial applications in plastics,
coatings, and films. The objective of this study was to synthesize different cellulose esters in a
novel distillable ionic liquid called 5-methyl-1,5,7-triazobicyclo-[4.3.0]non-6-enium acetate
[mTBNH][OAc], eliminating the need for external catalysts. To reduce the viscosity of the
overall solution, the co-solvent DMSO was added. Optimization of reaction parameters, such as
co-solvent content, temperature, time, and reactant ratios, was carried out. The structure and
degree of substitution (DS) of the cellulose esters were verified using advanced analytical
techniques including FTIR and NMR. The thermal properties of the cellulose esters were
evaluated using DSC, while their flow behavior as thermoplastics was studied using rheology.
The findings of this study indicate that transesterification of cellulose with vinyl esters in ionic
liquids is a promising environmentally friendly alternative to conventional esterification
methods. The use of the novel distillable ionic liquid, [mTBNH][OAc], for cellulose ester
synthesis without the need for external catalysts contributes to a more sustainable environment.
The incorporation of the co-solvent DMSO reduced the dissolution time for cellulose and
decreased the viscosity of the final solution, thereby making the overall synthesis more cost-
effective. Therefore, this study presents exciting opportunities for utilizing cellulose as a
sustainable raw material across various industrial applications. The study also opens the use of
bio-based co-solvents and esterfication agents to further enhance the sustainability.
References
1. Singh, R., Gupta, P., Sharma, O., Ray, S. (2015). Journal of Industrial and Engineering Chemistry 24, 14–
19.
2. Satgé, C., Granet, R., Verneuil, B., Branland, P., Krausz, P. (2004). C. R. Chimie 7, 135- 144.
3. Wen, X., Wang, H., Wei, Y., Wang, X., Liu, C. (2017). Carbohydrate Polymers 168, 247- 254.

15
MOLECULARLY IMPRINTED POLYMER NANOGELS - SYNTHETIC
PEPTIDE ANTIBODIES FOR BIOMEDICAL THERAPY AND
DIAGNOSTICS
Karsten Haupt
CNRS Laboratory for Enzyme and Cell Engineering, Université de Technologie de Compiègne, Rue du Docteur
Schweitzer, 60203 Compiègne, France
Molecularly imprinted polymers (MIPs) [1] are synthetic antibodies that specifically recognize
molecular targets. They are cross-linked polymers synthesized in the presence of a molecular
template, which induces three-dimensional binding sites in the polymer that are complementary
to the template in size, shape and chemical functionality. MIPs against proteins are obtained
through a rational approach starting with in silico epitope design. Chemically synthesized
peptide epitopes can then be used as templates in a solid-phase protocol for MIP synthesis. We
demonstrate the potential of MIP nanogels for diagnostics, bioimaging and medical therapy, on
the example of cell surface as well as soluble protein targets.
Reference
1. Haupt, K., Medina Rangel, P.X., Tse Sum Bui, B., Chem. Rev. (2020) 120, 9554-9582.

16
DEVELOMPENT OF NEW TRIPLET-TRIPLET ANNIHILATION
PHENOMENA BASED MATERIALS FOR OPTOELECTRONICS
A. Bucinskas1, A. Petrenko2, P. Arsenyan2, T-L. Chiu3, O. Bezvikonnyi1, D.
Volyniuk1, J. V. Grazulevicius1
1Department of Polymer Chemistry and Technology, Kaunas University of Technology, Kaunas, Lithuania
2Latvian Institute of Organic Synthesis, Riga, Latvia
3Yuan Ze University, Taoyuan City, Taiwan
Numerous degradation mechanisms of organic light emitting diodes (OLEDs) that influence
their lifetime were identified up today. For example, photochemical, electrochemical
degradation, thermal or electric breakdown, presence of impurities etc.[1] Additionally, triplet-
triplet or triplet‐polaron annihilation (TTA or TPA) phenomena were also identified as the
degradation mechanisms mostly observed for blue OLEDs with employed materials which
possess long-lifetime high-energy triplet excitons [2]. One of main solutions is the search of
new type of materials with much lower triplet energy (less than 1.8 eV) which employ TTA
mechanism in the generation of singlet exciton followed by formation of photon. Most of
efficient TTA emitters found by far are based on anthracene core [3]. In our work, in the search
of potential TTA emitters we synthesized several groups of materials by introducing
cyanotriphenylbenzene and anthracene core, respectively. In both series of new compounds
various 3,6-disubstituted carbazole fragments were introduced into main structure.
The results of investigation of the thermal, photophysical, electrochemical, photoelectrical and
charge-transporting properties of newly synthesized TTA emitters will be reported together with
the potential results of their performance in OLEDs.
Acknowledgement
This work was supported by the project of scientific cooperation program between Latvia, Lithuania and Taiwan
(grant LV-LT-TW/2023) and Research Council of Lithuania (LMTLT), Agreement No S-LLT-22-4.
References
1. Sudheendran Swayamprabha, S. et al. Approaches for Long Lifetime Organic Light Emitting Diodes.
Advanced Science, 2021, 8(1), P. 2002254.
2. Tanaka, M. et al. Understanding degradation of organic light-emitting diodes from magnetic field effects.
Communications Materials 2020 1:1, 2020 1(1), P.1–9.
3. Xing, L. et al. Anthracene-based fluorescent emitters toward superior-efficiency nondoped TTA-OLEDs
with deep blue emission and low efficiency roll-off. Chemical Engineering Journal, 2021, 421, P. 127748.

17
IONIC LIQUIDS RECYCLING
I. Krasnou, A. Krumme
Department of Materials and Environmental Technology, Tallinn University of Technology, Tallinn, Estonia,
illia.krasnou@taltech.ee
Extraordinary prices and lack of efficient recovery technologies limits scale-up utilization of
ionic liquids [1]. Ionic liquid recycling refers to the process of recovering and reusing ionic
liquids. Their widespread use has raised concerns about their environmental impact and cost,
leading to the development of recycling methods.
The recycling of ionic liquids typically involves the following steps:
Collection: Collected from industrial processes or research laboratories liquids may contain
impurities or be mixed with other substances.
Purification: The collected ionic liquids undergo purification processes to remove impurities,
contaminants, and any other undesired substances. Purification methods can include distillation,
solvent extraction, adsorption, or membrane filtration, depending on the specific properties of
the ionic liquid and the contaminants present.
Characterization: After purification, the ionic liquid is characterized to ensure it meets the
required quality standards. This step involves analyzing the physical, chemical, and
spectroscopic properties of the liquid to verify its composition and purity.
Reconditioning: If necessary, the ionic liquid may undergo reconditioning processes to restore
its desired properties or to adjust its composition to meet specific application requirements.
Reconditioning can involve adding certain additives or modifying the ionic liquid's structure.
Reuse or Disposal: Once the recycled ionic liquid meets the desired specifications, it can be
reused in the same or different applications. Reusing the ionic liquid reduces the demand for
new production and minimizes environmental impact. However, if the recycled ionic liquid
cannot be reused due to degradation or excessive impurities, it may be disposed of properly
according to environmental regulations.
The recycling of ionic liquids offers several advantages, including cost savings, reduced waste
generation, and decreased environmental impact associated with the production and disposal of
new ionic liquids. By implementing effective recycling strategies, industries can optimize their
resource utilization and contribute to a more sustainable and efficient chemical process.
Acknowledgement
RESTA10 by Estonian Research Council
Reference
1. W. Zheng, et al., Chemical Engineering Journal, 465, 2023

18
DIRECT INJECTION MOLDING WITH OPTIMISED SCREWS AND
ANALYTICS FOR ASSESSING THE MIXING QUALITY
Guntis Japins1, Jens Pape2, Ralf-Urs Giesen1, Hans-Peter Heim1
1 Institute of Material Engineering, Polymer Engineering, University of Kassel, Kassel, Germany
2 PAPE GmbH, Porta Westfalica, Germany
The standard process chain in plastics processing involves the compounding of initial polymers
with additives by using for example a twin-screw extruder. The resulting granulate is then
further processed into products with injection molding. Direct injection molding instead is a
combination of preparation (compounding) and shaping (injection molding) in one process. It
makes production faster, cheaper, more energy efficient and more flexible, which would allow
much faster variate composition of compounds due to fewer technological steps. Nevertheless,
despite all advantages that direct injection molding can have, it is still not popular in the industry
due to the challenges it brings. The most significant one is the mixing of several polydisperse,
organic and inorganic materials with a one screw machine. In current research the solution is
the replacement of the original screw in a conventional injection molding machine with special
mixing screws with a specific design to achieve higher mixing quality [1, 2]. In this research,
various screw configurations were tested and estimated. The mixing quality of all produced
materials was compared with the output of a standard screw and a standard compounding
material (twin-screw extruder). Materials used for mixing were a styrene-based elastomer,
polypropylene and a calcium carbonate powder. Mixing quality was evaluated with x-ray
microtomography, Shore A hardness tests and visual assessment. It was found that a clear and
robust solution for rapid and qualitative assessment of the degree of mixing is difficult to find..
Nevertheless, it was found that direct injection molding can be a perspective manufacturing
approach for future productions.
Acknowledgement
The study was carried out as part of the German state-funded project "Development of direct compounding
processes for the manufacture of single-use medical products (MeDiComP)"
Reference
1. Köpplmayr T., Altmann D., and Steinbichler G. Barrier Screw Design for High-Performance Plasticizing in
Injection Molding // Advances in Polymer Processing 2020, – 2020.
2. Rauwendaal C. Recent advances in barrier screw design // Plast. addit. compd., – 2005 – Vol.7, No. 5 –
P.36–39.

19
CHARACTERIZATION OF WOVEN ELECTROMAGNETIC
SHIELDING THERMOPLASTIC-FIBER COMPOSITES COMPARED
TO NON-WOVEN ELECTROMAGNETIC SHIELDING CONCEPTS.
Tristan Elsesser1, Angela Ries1, Hans-Peter Heim2
1Bielefeld Institute for Applied Materials Research, Bielefeld University of Applied Sciences, Bielefeld, Germany
2 Institute of Materials Engineering, University of Kassel, Kassel, Germany
As a result of necessary weight reductions and increasing proportions of functionally integrated,
modular systems, the construction and production methods are becoming increasingly compact
and complex. Thus, in addition to metallic materials, plastics are increasingly being used. In
contrast to metallic materials, fiber-reinforced plastics have significantly lower densities with
comparably high strength characteristics. Consequently, fiber-reinforced plastics offer a high,
specific lightweight construction potential with regard to possible applications in
electromobility concepts. At the same time, however, high demands are placed on the functional
and component safety of housings for electronic devices and systems that contain sensitive
sensors, applied and conductive elements. Undesirable electromagnetic couplings between the
electrical modules must be avoided. Plastics are dielectric, however, so magnetic and electric
fields can pass through the plastics attenuated. This can cause stray fields to emanate from the
individual electrical components, which in turn can cause interference in neighboring circuit
parts and even lead to significant failures of the electronics. The aim of this research is to
develop glass fiber composite semi-finished products with integrated, cost-effective protection
against electromagnetic influences based on unidirectional tapes and commercially available
metal-coated polymer woven materials. These composites are to be compared with already
explored composites with a metalcoated non-woven polymer fabric EMI layer. For this purpose,
glass fiber thermoplastic composites with various functional layers to form metallized woven
fabric were produced by hot pressing. The samples were analyzed and, based on this, the
processing procedure was optimized to achieve optimum consolidation of the hybrid composite.
A particular challenge is that the shielding component must remain intact in all process steps in
order to ensure the highest possible shielding effectiveness over a wide frequency range. The
subsequent comparison of the specially analyzed quasi-static and dynamic properties of the
hybrid composite concepts by means of quasi-static tensile and 3-point-bending tests as well as
shear load tests complete the investigation portfolio. From this, a comparison of the two
concepts of non-woven vs. woven fabric is derived with regard to the composite properties. This
research and development project is funded by the German Federal Ministry of Education and
Research (BMBF) within the “Forschungscampus” program (funding number 02P18Q750) and
implemented by the Project Management Agency Karlsruhe (PTKA).

20
POLYMER COMPOSITES FOR FRICTION AND SEALING UNITS OF
TECHNOLOGICAL EQUIPMENT
Оleh Kabat1, Volodymyr Sytar1, Janis Zicans2, Remo Merijs-Meri2
1Ukrainian State University of Chemical Technology, Dnipro-City, Ukraine
2Institute of Polymer Materials, Riga Technical University, Riga, Latvia
Polymer composites (PCs) occupy leading positions among other structural materials in modern
mechanical engineering.
It is known that according to BBC Research Report Overview “Engineering Resins, Polymer
Alloys and Blends: Global Markets” by April 2022, the global market of structural polymers
and composites based on them will increase from $70.7 billion in 2021 to $94.0 billion by 2026.
Taking into account a number of unique properties (low level of density with fairly high strength
values, resistance to the action of aggressive environments, the possibility of working in friction
and sealing units without and with insufficient oiling, etc.) PCs are especially often used in
friction and sealing units of technological equipment [1-3]. It is known [4] that friction and
sealing units make the greatest contribution to the reliability and durability of technological
equipment.
Therefore, it is an urgent task to develop such PCs that have a better level of properties than
analogues used in friction and sealing units of technological equipment, which will allow to
significantly improve its level of reliability and durability.
We developed PCs based on fluoropolymers and aromatic polyamides [4,5]. Density of these
materials is in the range from 1370 to 2200 kg/m3, stresses at the yield strength and elastic
modulus under compression reaches to 280 and 3600 MPa, нardness reaches to 250 MPa. Also
developed PCs have high level of heat resistance (to 460oC) and Vicat softening temperature (to
330oC). It can be stated that the developed PCs exceed metal alloys and approach low-carbon
steels in terms of their physical and mechanical properties. At the same time, according to the
investigated properties, they are at the same level and exceed the best foreign analogues based
on polymers [6,7].
Accordingly, it can be argued that the developed PCs when used in friction and sealing units of
technological equipment will contribute to the improvement of its reliability and durability than
the analogues in use.
References
1. Friedrich K. Polymer composites for tribological applications // Adv In Eng P Res. – 2018. – Vol. 1, No. 1 – P. 3–39.
2. Kobets A.S., Derkach O. D., Kabat O. S., Volovyk I. A., Kovalenko V. L., Kotok V. A. and Verbitskiy V. V. Investigation friction
and wear of constructional plastics based on aromatic polyamide // ARPN Jour. Eng. and Appl. Sci. – 2020. - Vol. 15, No. 10
– P. 1189-1195.
3. Kabat O., Sytar V., Derkach O., Sukhyy K. Рolymeric composite materials of tribotechnical purpose with a high level of
physical, mechanical and thermal properties // Chem & Chem. Tech. - 2021. – Vol. 15, No. 4. – P. 543-550.
4. Kabat O., Makarenko D., Derkach O., Muranov Y. Determining the influence of the filler on the properties of structural
thermal-resistant polymeric materials based on phenylone C1 // East-Eur/ Jour. Enter. Tech. – 2021. – Vol. 5, № 6 – Р. 24–
29.
5. Каbаt О.S., Derkach O.D., Pavlushkina N.V., Pikula І.І. Polymeric composites of tribotechnical purpose based on
fluoropolymers // Prob. Trib. – 2019. - Vol. 92, No. 2 – P. 75 – 81.
6. Advanced engineering design. Design for reliability / A. Van Beek - Delft: Delft University of Technology Mechanical
Engineering, 2012. - 115.
7. Fundamentals of Materials Science and Engineering: An Integrated Approach 6th Edition / W. Callister, D. Rethwisch - New
Jersey: Wiley, 2021.

21
SYNTHESIS OF ACTIVATED CHARCOAL / FERRIC FERROCYANIDE
HYBRID COMPOSITE MATERIALS FOR REMOVAL OF
RADIOACTIVE CESIUM FROM WATER
Karīna Anete Jefimova1, Uģis Eismonts2, Anna Ščerbicka3, Kristīne
Saleniece2, Andris Actiņš1, Rasa Stūrmane4, Artis Kons1, Ingars Reinholds1,
Māris Bērtiņš1, Arturs Vīksna1, Līga Avotiņa5, Gunta Ķizāne5, Andrejs
Grīnbergs5
1Faculty of Chemistry, University of Latvia, Riga, Latvia
2 Faculty of Medicine, University of Latvia, Riga, Latvia
3Agenskalns State Gymnasium, Riga, Latvia
4Riga State Gymnasium No. 1, Riga, Latvia
5Institute of Chemical Physics, University of Latvia, Riga, Latvia
The invasion of the Russian Federation in Ukraine and the deployment of nuclear warheads in
the Belarusian territories raise concerns of potential cross-border threats of radioactive fallouts
from the Nuclear Power Plants and danger to neighbor countries including Latvia attributed to
contamination of water, soil and food sources with radioactive cesium (Cs-137) causing threats
to human beings and animals.
Radiogardase-Cs is the antidote for Cs-137 based on the solid form of ferric ferrocyanide better
known as Prussian Blue (PB), which is approved in in many European countries, and the United
States of America, whereas it is not presently accessible within Latvian pharmaceutical
channels. There are not available proper water decontamination sorbents.
Based on the study of PB oral antidotes this study is dedicated to modification of by
physicochemical (ultrasonic) assisted and eco-safe mechanochemical methods resulting in
structure modified PB (SMPB) nanoparticles with adjusted size/structure for improved sorption
of radioactive cesium from water sources. The SMPB nanoparticles were used for the
development of nanocomposite materials with wood based activated charcoal (AC) composites
with different SMPB/AC ratios. Physicochemical methods based on Fourier-transform infrared
spectroscopy, X-ray diffractometry (XRD) and X-ray fluorescence spectroscopy (XRF) and
other methods were used to characterize the composites.
Water decontamination tests were provided based on artificially contaminated drinking, water
samples with stable cesium (Cs-133) salts followed by provided model studies of cesium
sorption- desorption mechanisms depending on the characteristics of the SMPB/AC. Changes
of cesium concentration were monitored by using inductively coupled plasma mass
spectrometry (ICP-MS) method and conformed sufficiently high adsorption of Cs from water
based on optimized sorbent conditions.
The characteristic 111 and 333 reflexes of the cubic lattice were for the the first determined by
the XRD method, which until now were found only by neutron diffractometry. Their presence
and precise measurements of intensities allow to assess their correlation with the sorption
properties of cesium ions in Prussian blue.
From the results it can be concluded that effective and ecosafe SMPB/AC sorbent was developed
for the decontamination of water from Cs-137.
Acknowledgement
Funding from the Ltd. "MikroTik" supported University of Latvia Foundation project "Creating extemporaneous prescription
of highly toxic and radioactive compounds of cesium, thallium and rubidium antidote" is acknowledged.

22
HIGH PERFORMANCE EMI SHIELDING POLYMER COMPOSITES
Sergejs Gaidukovs, Miks Bleija, Oskars Platnieks
Institute of Polymer Materials, Faculty of Materials Science and Applied Chemistry, Riga Technical University,
P. Valdena 3/7, Riga LV-1048, Latvia
sergejs.gaidukovs@rtu.lv
The escalating challenges in safeguarding society against military, cyber, and hybrid threats
have underscored the necessity for novel defence strategies. Among these challenges, securing
mission-critical equipment and vital infrastructure against electromagnetic threats stands out.
Key components of society's functioning, such as energy distribution networks, information and
communication technologies, transportation systems, security mechanisms, and financial
stability, are all vulnerable to electromagnetic interference (EMI). Despite modern
advancements, mitigating high-frequency EMI remains a formidable issue.
A particularly concerning aspect is the proliferation of relatively compact, cost-effective yet
potent high-frequency devices in the possession of terrorist groups. This dynamic threat
landscape introduces new complexities. Addressing these challenges presents a significant
opportunity for the advancement of emerging advanced polymer materials tailored for
cybersecurity applications.
Acknowledgement
This research was funded by the Latvian State Research Program for Defense Innovation, Project “Enhanced
electromagnetic protection and cybersecurity through field-deployable innovative shielding, monitoring and data
destruction technologies”, Nr. VPP-AIPP-2021/1- 0007.

23
A CONTRIBUTION TO CIRCULARITY OF PLASTICS:
THERMOPLASTICS LIGHTWEIGHT MATERIALS, BIO-BASED
PLASTICS AND MATERIAL-FLOW-ORIENTED RECYCLING
Prof. Dr.-Ing. Maik Feldmann
Head of Business Unit Polymer Applications at Fraunhofer Institute for Microstructure of Materials and Systems
IMWS - Halle/Germany
Head of Polymer Processing Fraunhofer Pilot Plant Center for Polymer Synthesis and Processing PAZ -
Schkopau/Germany
Professor for Polymer Processing - University of Applied Science in Merseburg/ Germany
In the last few years, in addition to the reduction of CO2 emissions by using renewable raw
materials, for example, the aspect of "sustainability through increased recycling management"
has also become increasingly important. Some future scenarios assume that in the middle of this
century just a low 2-digit percentage of plastic products will consist of renewable raw materials
and that these will also have to be recycled in order to meet losses but also the increasing demand
for raw materials due to global growth. Some of these goals are already being addressed through
increasing regulation, such as increasing recycling quotas. However, there is also a drive
towards independence from fossil raw materials, which is also a major global dependency for
many countries.
The demand for more circularity gives rise to many different technical issues and challenges.
On the one hand, new materials are being developed and researched, especially from alternative
raw material sources. On the other hand, functioning material cycles and recycling processes
already exist for some material flows, which are partly opposed to the material diversity and
innovations. At this point, e.g., cascading recycling concepts can be advantageous, whereby the
complexity increases arbitrarily and support by IT-supported evaluation software becomes
necessary in order to optimize the different criteria as much as possible.
In addition to the material aspects, suitable design methods for weight reduction in combination
with comparatively easy-to-recycle materials are also playing an increasingly important role.
Many thermoset applications are increasingly being implemented with thermoplastic materials,
and ideally with a minimum amount of material, such as in the area of load-path-compliant
reinforcement with continuous fibers.
The presentation highlights different aspects and presents examples from ongoing projects at
the Fraunhofer IMWS in Halle and Schkopau in cooperation with Merseburg University of
Applied Sciences and other research institutes.

24
POLYMER BRUSH COATED UPCONVERTING NANOPARTICLES
WITH IMPROVED COLLOIDAL STABILITY AND CELLULAR
LABELING
V. Klimkevičius1,2, G. Jarockyte2, K. Bolgova1, A. Katelnikovas1 and V.
Karabanovas2
1Institute of Chemistry, Vilnius University, Naugarduko 24, LT-03225 Vilnius, Lithuania,
2Biomedical Physics Laboratory of National Cancer Institute, Baublio 3B, LT-08406,
Vilnius, Lithuania. vaidas.klimkevicius@chf.vu.lt
Upconverting nanoparticles (UCNPs) hold significant potential for biomedical applications,
particularly in the fields of cancer treatment and imaging. These nanoparticles possess the ability
to absorb near-infrared (NIR) light and convert it into visible (Vis) and ultraviolet (UV)
radiation. The NIR excitation enables deep tissue penetration through the 'biological NIR
window.' The emitted UV-Vis and NIR photons can be utilized for cancer therapy and imaging,
respectively, making UCNPs highly valuable for combined diagnostics and therapy [1].
However, the synthesis procedure of UCNPs involves the use of organic solvents, resulting in
their hydrophobic nature, which leads to unstable behavior in aqueous solutions and poor
biocompatibility. To address this issue, the surface of UCNPs can be coated with amphiphilic
polymers or phospholipids, which not only hydrophilize the UCNPs but also facilitate the
attachment of various biomolecules [2].
In this study, we demonstrate the successful surface modification of
LiYF4: Tm3+,Yb3+ UCNPs via exchange of hydrophobic oleate ligands with custom-made
anionic polyelectrolytes p(MAA-co-PEG9MEMA). We have observed that the composition of
the synthesized polyelectrolytes affects the stability and optical properties of UCNPs. Our
results demonstrated that the number of anchoring anionic groups in the polymer has a greater
effect on the long-term colloidal stability of UCNPs than the number of PEGylated substituents.
UCNPs modified with the P9MAA-75 polyelectrolyte, containing a large number of anionic
anchoring groups, showed exceptional long-term stability in all three investigated media: DI
water, DMEM, and DMEM + 10% FBS. Furthermore, the surface modification with a highly
charged P9MAA-75 polyelectrolyte yielded additional increase of their upconversion emission
intensity as compared to that of the bare UCNPs. Finally, the polymer coating has a vital role in
UCNP cellular uptake. In protein-rich media, UCNPs modified with the P9MMA-25
polyelectrolyte exhibit higher cellular accumulation compared to P9MMA-75 modified
counterparts. On the other hand, P9MMA-75 modified UCNPs could be used for cellular uptake
investigation in protein-free media, where P9MMA-25 modified UCNPs are significantly less
stable. In conclusion, LiYF4:Tm3+,Yb3+ UCNPs modified with anionic polyelectrolytes
p(MAA-co-PEG9MEMA) demonstrated good biocompatibility and exhibited enhanced
accumulation in both phenotypes of breast cancer cells. Therefore, these UCNPs can be
considered suitable candidates for future development of targeted carcer therapy
Acknowledgement. This project has received funding from the Research Council of Lithuania (LMTLT),
agreement No [S-MIP-22-68].
References
1. J. F.-C. Loo, Y.-H. Chien, F. Yin, S.-K. Kong, H.-P. Ho and K.-T. Yong, Coord. Chem. Rev., 2019, 400, 213042.
2. E. Voronovic, A. Skripka, G. Jarockyte, M. Ger, D. Kuciauskas, A. Kaupinis, M. Valius, R. Rotomskis, F. Vetrone and
V. Karabanovas, ACS Appl. Mater. Interfaces,2021, 13, 39076–39087.

25
DESIGN AND SYNTHESIS OF THE DONOR-ACCEPTOR-DONOR
TADF MOLECULES FOR APPLICATION IN OLED
Nor Shafiq M. Jamel1, Levani Skhirtladze2, Muhammad Kumayl A. Wahab1,
Kai Lin Woon3, Aqeel A. Hussein4, Juozas V. Grazulevicius2 and Azhar
Ariffin1,2*
1Department of Chemistry, Faculty of Science, Universiti Malaya, 50603 Kuala Lumpur, Malaysia.
2Department of Polymer Chemistry and Technology, Faculty of Chemical Technology, Kaunas
University of Technology, Lithuania.
3Department of Physics, Faculty of Science, Universiti Malaya, 50603 Kuala Lumpur, Malaysia
4Department of Medical Laboratory Science Komar University of Science and Technology
Sulaymania, 46001, Iraq
Organic light emitting diodes (OLED) are widely used in the display technology. It is considered
as the main competitor to the existing display technologies such as liquid crystals and light
emitting diodes (LED). OLED system relies solely in the organic emitters. The latest generation
of OLEDs uses the thermally activated delayed fluorescence (TADF) as the operating principle.
One of the important criteria in design TADF molecules is the smallest possible energy gap
between the first excited singlet state (S1) and first excited triplet state (T1). This energy gap is
referred to as EST. One of the approaches to achieve small EST, is the design of molecules
with a twisted C(sp2)-N connection between donor (D) and acceptor (A) moieties.
Our interest in the development of Donor-Acceptor-Donor (D-A-D) TADF molecules prompted
us to explore the design of the TADF molecules and methods for the formation of C(sp2)-N
bond between the donor and acceptor units. TD-DFT were used in the design of the molecules.
Carbazole, substituted carbazole, phenoxazine, phenothiazine, and acridine are normally used
as the donors (D), whereas 1,4-disubstituted phenylene motif is the acceptor. We have recently
reported the synthesis of D-A-D type TADF compounds via a two-fold Buchwald-Hartwig
reaction. Combination of Pd2(dba)3/XPhos was used as catalyst [1] Here we report on the design
and synthesis of TADF molecules. We have successfully reduced the reaction time of the two-
fold Buchwald-Hartwig amination reaction from 12 – 24 h to 10 – 30 minutes assisted by the
microwave synthesizer. To our knowledge, this is the first report on the two-fold decrease of the
duration of the Buchwald-Hartwig amination reaction.
Reference
1. Skhirtladze L, Leitonas K, Bucinskas A, Volyniuk D. Y, Mahmoudi M, Mukbaniani O, Woon K. L, Ariffin A,
and Grazulevicius J. V. 1,4-Bis(trifluoromethyl)benzene as a new acceptor for the design and synthesis of
emitters exhibiting efficient thermally activated delayed fluorescence and electroluminescence:
experimental and computational guidance, J. Mater. Chem. C, 2022,10, 4929-4940. DOI:
10.1039/D1TC05420A

26
THERMORESPONSIVE POLYMERS: FROM SYNTHESIS TO
APPLICATIONS
Ramune Rutkaite
Department of Polymer Chemistry and Technology, Kaunas University of Technology, Kaunas, Lithuania
Stimuli-responsive polymers can be triggered by various stimuli (e.g., temperature, pH, ionic
strength, redox reactions, light, shear stress, enzymes, etc.) and change their physical properties,
which can lead to dramatic changes in the macroscopic behaviour of polymer solutions,
semisolid and solid formulations thereof. This permits also a certain control over properties of
particles other formed bodies made of such polymers by environmental conditions that are
characterized by changes in wetting properties of surfaces, charge density, topography, porosity,
swelling and others.
Polymers able to respond to environmental stimuli have been recently under growing
consideration to impart a “smart” behavior to the final product, which is highly desirable to
provide it with a specific dynamic and an advanced function. In particular, thermo-responsive
polymers, materials able to undergo a discontinuous phase transition or morphological change
in response to a temperature variation, are among the most studied.
The development of various polymerization techniques has paved the way to a high degree of
engineering for the polymer architecture and properties, which in turn brought to a plethora of
sophisticated behaviors for these polymers by simply switching the external temperature. These
can be exploited in many different fields, from separation to advanced optics, biosensors and
biomedical applications.
Within these contexts, this presentation highlights the opportunities, challenges and future
trends related to the latest advances in the development of thermoresponsive materials and their
applications, with the focus on the structural and design aspects that are required to exploit such
materials for cutting-edge applications in the biomedical field.
Furthermore, our achievements in synthesis of thermoresponsive graft copolymers based on
synthetic and biopolymers, and studies of their properties will be discussed.

27
CORRELATIONS BETWEEN THERMOHYGROSCOPIC INFLUENCES
AND MECHANICAL PROPERTIES IN WOOD-TEXTILE COMPOSITES
(WTC)
Claudia L. von Boyneburgk, Jan-Christoph Zarges, Hans-Peter Heim
Institute of Material Engineering, Polymer Engineering, University of Kassel, Kassel, Germany
Wood-textile composites (WTC) based on willow wood fabrics and polypropylene were
produced using a hot compacting process in order to open up new and innovative areas of
applications for wood (Fig 1). Human sensory studies showed, that the design of the material is
perceived as very positive by the participants on both a visual and a haptic level [1]. This is why
WTCs appear to be particularly suitable for use in areas with a high visual impact, for example
as a facade element. In tensile tests supported by digital image correlation (DIC) and 3-point
bending tests it was shown, that the mechanical properties of WTCs are strongly dependent on
the heterogeneous structure of the composite. Both strength and elongation depend on the
loading direction and show a classical fibre reinforced composite behaviour despite the
comparatively large dimension of the filaments [2]. In addition, the WTCs were subjected to
various conditioning procedures and a subsequent impact bending test (Fig 2). It was shown that
changing environmental conditions, in particular temperature and humidity, have a strong
influence on the mechanical behaviour of the material [1].
Fig 1: Wood Textile Composite (WTC)
Fig 2: Correlation between moisture content and
impact bending strength in WTC
The investigations carried out were possible to prove, that the characterization of WTC is
possible with conventional test methods. However, the strong dependence on environmental
influences requires further investigations and future modifications of the composite material to
make outdoor use possible.
Acknowledgement
This work was supported by the project „VOTO - Weidengewebeverstärkter Kunststoff mit variabler Gewebedichte für
Fassadenelemente im textilen Holzbau“, funded by the Federal Ministry for Economy and Energy based on a resolution of the
German Bundestag.
Reference
1. C. von Boyneburgk, S. Silbermann, L. Schweiger, J.-C. Zarges, H. Klussmann, and H.-P. Heim, “Holzdesign trifft
Kunststofftechnik,” Kunststoffe, no. 6, pp. 82–85, 2022.
2. C. L. von Boyneburgk, J.-C. Zarges, D. Kuhl, and H.-P. Heim, “Mechanical Characterization and Simulation of Wood
Textile Composites (WTC) supported by Digital Image Correlation (DIC),” Composites Part C: Open Access, vol. 11, p.
100370, 2023, doi: 10.1016/j.jcomc.2023.100370.

28
MOLECULARLY IMPRINTED POLYMER AS A SELECTIVE
RECOGNITION ELEMENT FOR DETECTION OF AZOXYSTROBIN IN
AQUEOUS MEDIA
Vu Bao Chau Nguyen, Jekaterina Reut, Vitali Syritski
Department of Materials and Environmental Technology, Tallinn University of Technology, Tallinn, Estonia
Azoxystrobin (Az) is a broad-spectrum systemic fungicide that is widely used to protect crops
from fungal diseases. The increasing global use of Az has led to concerns regarding its presence
in the aqueous environment that impacts directly and indirectly on human health [1].
Consequently, there is an urgent need to develop selective and reliable detection methods to
monitor Az concentrations in water, ensuring environmental safety and public health.
To address this challenge, the present study focuses on the development of an electrochemical
Az sensor utilising a Az-selective molecularly imprinted polymer (Az-MIP) as the recognition
element, for the detection of Az compounds in aqueous matrices and the thin metal electrode
(TFME) system connected to an electrochemical workstation to measure different pulse
voltammetry-based signal (DPV). The Az-MIP was electrochemically synthesised on the
working electrode of TFME, employing dual functional monomers. Several electro-
polymerizable monomers (2-methyl-4-nitroaniline, 3-aminothiophenol, aniline, meta-
phenylenediamine, pyrazole, and pyrrole) were assessed as possible monomers for synthesis of
Az-MIP. Aniline was rationally selected due to its superior binding energy in the complex with
Az, while meta-phenylenediamine functioned as an effective cross-linking agent, facilitating the
formation of a three-dimensional polymeric network containing tailored recognition sites for
Az.
The optimization of various synthesis parameters was conducted to enhance the overall
performance of the sensor. These parameters included monomer concentration ratios, solution
pH, charge density of the galvanostatic electrodeposition process, and incubation time.
Additionally, DPV settings, such as potential step, pulse width, and pulse size, were optimised
to quantify small relevant Az concentrations accurately and precisely in water.
The preliminary results demonstrate that MIP-based sensors achieved a low limit of detection
of 2.0 nM and limit of quantification of 6.8 nM, indicating their high sensitivity. Furthermore,
a good selectivity was displayed towards azoxystrobin in both milli-Q and tap water samples.
This study showcases the potential of MIP-based electrochemical sensors for onsite detection
of environmental contaminants in water, as well as the advancement of analytical tools for water
quality monitoring and risk assessment.
Acknowledgement
This work was supported by the Estonian Research Council (grant PRG307).
References
1. E.T. Rodrigues, I. Lopes, M. Pardal, Occurrence, fate and effects of azoxystrobin in aquatic ecosystems: A
review, Environment International. 53 (2013) 18–28.

29
UV CURING COATINGS ON NATURAL NAILS
Z.Grigale-Sorocina, I.Briks
Department of Research and Development, Kinetics Nail Systems Ltd., Kurzemes prospekts 3K, Riga, LV-1067,
Latvia
UV-curing nail coatings have gained immense popularity for their rapid curing time and
enhanced performance compared to coatings formed by drying polymer solutions [1]. The
crucial aspect in formulating such coatings lies in understanding the methods needed to develop
compositions that can achieve robust adhesion to the natural nail [2].
Coatings on natural nails possess specific technological properties, resulting in coatings with
distinct physical-mechanical, surface, and adhesion characteristics. Therefore, the experience
gained from current UV-curable coatings is not directly applicable [3].
The practical aim of this research was to devise a methodology for creating a composition that
effectively polymerizes under controlled UV radiation, resulting in a coating that meets all the
specified requirements for nail coatings.
A comprehensive methodology has been developed for the formulation of acrylate composite
systems and for obtaining suitable cosmetic coatings through the process of UV-activated
copolymerization. Throughout the investigation, industry-defined coating requisites were
determined. Critical testing parameters, including rheological properties, surface wetting, color
stability over time, polymerization duration and temperature, surface gloss, adhesion, and
solubility of coatings were identified. The methods for their determination were also established.
Simultaneously, the study unveiled existing challenges within the current Research and
Development laboratory framework. These challenges encompassed ensuring foundational
adhesion of the base layer to natural nails, guaranteeing the safety of raw materials, improving
the color saturation of pigmented coatings, and enhancing the polymerization capabilities of
pigmented coatings.
References
1. Jančovičová V., Mikula M., Havlinova B. Prog. Org. Coat., 2013, 76 (2–3), 432–438.
2. Haile D. L. USA Patent WO 2011/011304 A2, 2011.
3. Murdan S., Kerai L., Hossin B. J. Drug Deliv. Sci., 2015, 25, 23–28.

30
POLYURETHANES FOR GLASS SEALANTS – EVOLUTION FROM
FOSSIL-BASED TO RENEWABLE FEEDSTOCKS
J. Jaunbergs
Research and Development Laboratory, Tenachem Ltd., Spodribas iela 3, Dobele LV-3701, Latvia
Polyurethane sealants are currently the most common type of sealant giving structural strength,
moisture resistance, and gas barrier performance to insulated glass units used in Europe. While
the performance requirements tend to become stricter, rising prices of fossil-based chemicals
and ultimately the expected depletion of fossil hydrocarbon deposits provide a clear signal that
sustainable alternatives must be introduced.1 For polyurethanes, this means introducing
renewable plasticizers, polyols, and polyisocyanates. One option is direct use of bio-based liquid
chemicals,2 such as vegetable oils, diols, and carboxylic acids. Another, more conservative
approach is the production of traditional petrochemicals from hydrocracker gas stream that can
be fed by bio-based oils or other organic liquids. Regardless of the production method, these
bio-based polyurethane starting materials are subject to the same principal requirements – low
viscosity and easy miscibility, functionality of 2-3 hydroxy groups or isocyanate groups per
molecule, low dispersity of functionality among molecules, in order to obtain rubber-like high-
strength elastomeric sealants. New types of suitable materials appear not only from botanical
sources, but also as a result of biotechnological innovation. Only a few of these novel materials
are currently used in polyurethane glass sealants.
References
1. Cywar, R.M., Rorrer, N.A., Hoyt, C.B. et al. Bio-based polymers with performance-advantaged properties.
Nat Rev Mater 7, 83–103 (2022). https://doi.org/10.1038/s41578-021-00363-3
2. Tran, M.H., Lee, E.Y. Production of polyols and polyurethane from biomass: a review. Environ Chem Lett
21, 2199–2223 (2023). https://doi.org/10.1007/s10311-023-01592-4.
3. Sardon, H., Mecerreyes, D., Basterretxea, A., Averous, L., Jehanno, C. ACS Sustainable Chem. Eng. 9, 32,
10664–10677 (2021). Publication Date:July 30, 2021. https://doi.org/10.1021/acssuschemeng.1c02361

31
PROCESSING OF BIOCOMPOSITES CONTAINING HEMP SEED HULL
WASTE
Joana Bendoraitiene, Gabija Kuzminskaite, Viktorija Perepecajava, Rokas
Jakubauskas, Dovile Liudvinaviciūte, Laura Peciulyte, Ramune Rutkaite
Department of Polymer Chemistry and Technology, Kaunas University of Technology, Kaunas, Lithuania
Hemp is a high yielding annual crop currently experiencing a revival in production. Hemp fiber
contains pectin, hemicellulose and lignin, while hemp seed oil contains unsaturated triglycerides
with well-established nutritional and physiological properties [1]. The amount of waste
increases with the growth of consumption, therefore, focus on the utilization of hemp processing
waste in various industries is increasing globally. Hemp fiber is especially widely studied and
used for biocomposites. It is known that hemp seed hulls (HH) can be used as fertilizer and
cattle feed, however, the data on the use of this waste material in the production of bioplastic
composites is scarce.
The aim of the work is to study the formation of thermoplastic biocomposites based on hemp
seed hulls and other biobased materials of plant origin and to assess their mechanical properties.
The hemp composite mixture was obtained by mixing hemp seed hulls (HH) of various particle
size with cellulose acetate (AC) granules, which served as a binding material, and a plasticizer
triacetin (TA). The content of TA in the compositions was 35%, the content of hemp seed hulls
was 10% - 30%. Three fractions of crushed hemp shells were used: < 0.16 mm, 0.16 - 0.63 mm
and 0.63 - 1.00 mm. The formation of bioplastic material was carried using a twin-screw
extruder at a temperature of 130-190 C. The production process to obtain thermoplastic
biocomposites is presented in Fig 1.
Fig. 1 Biocomposite pellet production process involving hemp hulls of various size: 1 – < 0.16 mm, 2 – 0.16-0.63
mm and 3 – 0.63-1.00 mm
The bioplastics of various composition were obtained. The effect of the amount of HH and
particle size on the melt flow characteristics and mechanical properties of the products was
evaluated.
References
1. Khwanchat P., Atcharawan S. and Nathdanai H. Applications of Hemp Polymers and Extracts in Food, Textile and
Packaging: A Review // Polymers. – 2022. – Vol. 14, No. 20. – P. 4274.

32
INVESTIGATION OF DIFFERENT NATURE POLYMERIC 3D
PRINTED HEELS FATIGUE BEHAVIOUR
Edita Gelažienė , Daiva Milašienė
Department of Production Engineering, Kaunas University of Technology, Kaunas, Lithuania
The rapidly growing popularity of 3D printing technology enables the production of customised
product designs, the creation of complex geometric shapes, and the reduction of waste in various
industries. Therefore, 3D printing technology can be integrated into the production of
orthopeadic footwear, which can facilitate and accelerate the production of customised
footwear. The traditional method of making orthopeadic footwear has many limitations when it
comes to adapting a specific design that meets the requirements of the movement function and
combines the various details of footwear production.
In this work, 7 polymeric materials are used for the additive manufacturing process: PLA, ABS,
PTEG, PA (NYLON), and TPC printed by the FDM method, PA12 by the SLS method, and
photopolymer by the SLA method. These materials have high mechanical strength, hardness,
thermal stability, wear resistance, and better adhesion than parts made from standard materials
and are increasingly used in industry and research. It must be ensured that 3D printed parts resist
mechanical and environmental influences. Therefore, it is important to investigate the
mechanical strength of 3D printed polymer materials, especially their fatigue behaviour under
cyclic loading conditions, as this could lead to fatigue crack propagation and material failure.
The fatigue mechanism of 3D printed polymers is very important for the evaluation of these
materials in structural applications. Therefore, this study aims to evaluate the fatigue properties
of polymer materials for 3D printed shoe heels.
Cyclic compression tests were performed using a universal testing machine, Instron ElectroPuls
E10000T. The 3D printed heel prototypes made of seven polymers of different natures were
tested under fatigue loading at a frequency of 0.5 Hz and pressed up to a load of 1000N. Fatigue
was applied in 50000 cycles simulating 8 hours of brisk walking. The changes in energy
absorption with an increasing number of load cycles were analysed. The influence of the nature
of the polymeric material used on fatigue behaviour was also assessed.

33
STUDIES OF POSSIBILITIES OF SYNTHETIC FIBRES SURFACE
MODIFICATION WITH CUXSE
Daiva Milašienė 1, Olga Belukhina 1, Remigijus Ivanauskas2
1Department of Production Engineering, Kaunas University of Technology, Kaunas, Lithuania
2Department of Physical and Inorganic Chemistry, Kaunas University of Technology, Kaunas, Lithuania
Recently, researchers have faced the challenging task of finding a way to use industrial waste
as secondary raw material for new applications. At this time, it has often been emphasised that
textile waste is one of the largest sources of pollution in the world. The use of industrial textile
waste for the creation of new functional composites is a viable area for the development of
sustainable technologies. New composite materials for special purposes with varying
combinations of physical and chemical properties can be obtained by using polymers modified
with thin semiconductive or electrically conductive layers of binary inorganic compounds. In
recent decades, semiconductor nanomaterials have received great attention of attention because
of their novel electronic, optical, photoelectric, and thermoelectric properties. As an important
semiconductor, copper selenide (CuxSe) with nanostructure has potential applications in various
fields, such as optical filters, highly efficient solar cells, superionic conductors, electro-optical
devices, photothermal conversion, electroconductive electrodes, microwave shielding coatings,
etc.
In this study, part of the results of the investigation of possibilities of the formation of the copper
selenide layer on the surface of the different fibres is presented. In previous work, the
possibilities of modifying natural fibres with copper selenides were explored. The modified
method was based on a two-stage adsorption-diffusion process. In this work, the possibility of
applying analogous modification conditions to the treatment of synthetic fibres was sought. In
the work, thread waste from Lithuanian companies was investigated. Synthetic fibres of
different natures PA6, PA6.6, PES, and PAN were used for this experiment. It was found that
the quality of formation of copper selenide crystal layer coating on the surface of the
investigated all type fibres is highly dependent on the number of modification cycles.

34
DEVELOPMENT OF A BIOBASED COMPATIBILIZER AND ITS
EFFECT ON RAPESEED FIBRES STRUCTURE AND PROPERTIES OF
RECYCLED POLYMER COMPOSITES
Z. Iesalniece1,2, R. Bērziņa1, R. Bērziņš1, A. Ābele1, J. Zicāns1, R. Merijs-Meri1
1Institute of Polymer Materials, Faculty of Materials Sciences and Applied Chemistry, Riga Technical University,
3 Paula Valdena street, Riga, LV-1048, Latvia
2 Ltd. SAKRET, Rumbula, Latvia
The trend in recent years has been to promote a circular economy and save non-renewable
resources. Polymers most commonly are used in composites, where they can be combined with
other polymers or fillers to produce a composite with desired properties. For example, natural
fiber composites are an excellent way to obtain high-strength materials. However, to achieve
this, the best possible compatibility between polymer matrix and natural fibers must be ensured.
According to literature natural fibers need to be pretreated to obtain better interfacial
interactions. Besides, it is necessary to use compatibilizers in creation of composites in order to
improve the compatibility between polymer matrix and natural fiber, obtaining materials with
higher mechanical properties. Maleic anhydride (MAH) grafted polymer is a compatibilizer,
which is very effective and commonly used for natural fiber and polymer matrix at the interfacial
agent. MAH is produced from non-renewable resources, so the aim of the work was to develop
biobased compatibilizers and assess their effectiveness.
Tannic acid (TA), catechin hydrate (CA) and stearic acid chloride (SC) were used for the
synthesis of the biobased compatibilizers (SCTA and SCCH). The synthesis process was carried
out according to modified procedure of M.M.S.Abdullah [1].
The compatibilizer effect was evaluated for recycled polypropylene/polyethylene compositions
with 10 % and 40 % rapeseed straw fibers.
The results of mechanical properties (tensile, flexural, impact strength) showed that the
developed compatibilizers have the potential to replace MAH. Moreover, the addition of SCTA
and SCCA to the composite showed excellent thermo-oxidative properties, providing very high
stabilization in oxygen environment at 190 °C. Composites formed with SCTA and SCCA
showed high surface wetting properties than with MAH; the wetting angle reached up to 90°,
granting a more hydrophobic surface.
Acknowledgment
This work was supported by the Latvian Council of Science in the framework of FLPP “Obtaining multi-
functional bio-based compatibiliser and its effect on the performance of recycled polymer composites with
biomass reinforcement”, lzp-2021/1-0347.
Reference:
1. M.M.S.Abdullah, H.A.Al-Lohedan. Synthesis and characterization of tannic acid esters and their
performances as asphaltenes dispersants. J. Pet. Sci. Eng., 2021, 201, 108389.

35
EFFECT OF CARBOXYLIC ACIDS AND TANNIC ACID AS
COMPATIBILIZER ON MECHANICAL PROPERTIES OF RECYCLED
POLYOLEFIN COMPOSITES WITH NATURAL FIBERS
A. Ābele, R. Bērziņa, I. Bočkovs, S. Motrončiks, J. Zicāns, R. Merijs-Meri, R.
Bērziņš
Institute of Polymer Materials, Faculty of Materials Sciences and Applied Chemistry, Riga Technical University,
3 Paula Valdena street, Riga, LV-1048, Latvia
There has been an increased interest in producing more environmentally friendly materials. Polymer
composites reinforced with lignocellulosic fibres seems to be an attractive source. The challenge of this
type composites is compatibility between polymer matrix and lignocellulosic reinforcement. Interfacial
adhesion between polyolefin and lignocellulosic fibers may be increased by adding compatibilizer, such
as maleic anhydride grafted polymer (MA), but MA is expensive, non-biodegradable.
The use of multi- functional compatibilizer on the bases of carboxyl acid (CA) and tannic acid (TA) is
good possibility to replace synthetic agents because carboxylic acid’s carbon chain shows affinity to PP,
but carboxylic group provides interaction with hydroxylic groups of lignocellulose fibers. Moreover,
TA is natural source of polyphenol and is effective antioxidant due to its free radical scavenging capacity.
Modification through esterification reduces hydrophilicity of tannins, improves compatibility with
hydrophobic polymer matrix and shifts UV absorbance region by improving UV stability of the polymer
matrix.
In the work carboxylic acids with different chain lengths were selected for development of bio based
compatibilizers with TA. Carboxylic acids modification with TA is performed through esterification
reaction to get multi-functional compatibilizer.
The compatibilizer effect was evaluated for recycled polypropylene/polyethylene compositions with 10
% buckwheat straw fibers.
From the obtained results was observed that modulus of elasticity increases by 30%. The reinforcement
effect was found slightly higher by adding MAH. In the same time compositions with new bio based
compatibilizer are characterized with higher tensile elongation than MAH containing compositions.
After UV test (2 weeks), similarly to the MAH compatibilized systems, an increase in, e.g., tensile
modulus, yield strength, was observed for the composition with bio based compatibilizers. Meanwhile,
tensile elongation at break, B, values of the biobased compatibilizer containing systems showed greater
reduction than in the of MAH compatibilized compositions.
Acknowledgment
This work was supported by the Latvian Council of Science in the framework of FLPP “Obtaining multi-functional
bio-based compatibiliser and its effect on the performance of recycled polymer composites with biomass
reinforcement”, lzp-2021/1-0347.

36
MECHANICAL BEHAVIOR OF THE LIGNOCELLULOSIC FIBER-
REINFORCED RECYCLED PP/PE COMPOSITES
I. Bochkov1, M. Žiganova1, A. Ābele1, R. Merijs-Meri1
1Institute of Polymer Materials, Faculty of Materials Sciences and Applied Chemistry, Riga Technical University,
Riga, Latvia
Now days, it is impossible to think, about our everyday life, without polymer packaging
materials, building and constructions, modern design furniture parts and etc. Europe plastic
market data shows that in 2021 plastic production and demand got higher then before COVID
2019 pandemic. Production of fossil plastic on the same level as 2019 but post-consumer
recycled plastic and bio-based plastics production growing. As data shows it is easy to recycle
separately collected plastic (recycling rate 65%) and there is a great problem in case of mixed
collected plastic (recycling rate 5%). Plastic with impurities and plastic blend recycling is one
the edge (PP/PE, HDPE/LDPE, PC/ABS etc) [1].
This work contains matrix material recycled polypropylene/polyethylene mix rPPPE matrix that
is not as popular as pure PP or PE recycled materials.
Last decade biobased polymers become more and more popular. Main component for biobased
polymer composites is natural fibres. Most used are wood, sisal, hemp, coconut, cotton, kenaf,
flax, jute, abaca, banana leaf, bamboo fibers. Most of them crosses with food security problem
(corn as food or bio diesel fuel). That why for this work we decided to take a sweet clover fibre
(SCS) which has limited use in the agricultural sector. SCS contain similar amount of cellulose
as well known and investigated fibre. In the same time others authors works showed that SCS
fibres could be perspective in practical use for biobased composites [2, 3]. To increase possible
composite blend application field, we used 40 wt % of fibres it is maximal possible content for
traditional injection moulding technology or extrusion process.
The work presents the variation of the mechanical properties of the composite (tensile, flexural,
impact strength) using SCS.
Acknowledgement
This research was funded by The Latvian Science Council, grant number LZP 2021/1-0347.
References
1. Plastics the facts. https://plasticseurope.org/knowledge-hub/plastics-the-facts-2022/
2. Žiganova M., Ābele A., Iesalniece Z., Merijs Meri R. Mercerization of Agricultural Waste: Sweet Clover,
Buckwheat, and Rapeseed Straws // Fibers – 2022 10(10). https://doi.org/10.3390/fib10100083
3. Ābele A., Merijs-Meri R., Žiganova M., Iesalniece Z., Bochkov I. Effect of Agricultural Biomass Residues
on the Properties of Recycled Polypropylene/Polyethylene Composites. // Polymers (Basel). 2023 Jun
14;15(12):2672. doi: 10.3390/polym15122672.

37
PREPARATION OF SILANE-TREATED LIGNOCELLULOSIC FIBRES
FOR POLYMER COMPOSITES
S. Motrončiks, R. Bērziņš, A. Ābele, R. Merijs-Meri
Institute of Polymer Materials, Faculty of Materials Science and Applied Chemistry, Riga Technical University,
Paula Valdena 3/7, Riga, Latvia
Every year the demand for polymer materials grows. This increased demand means that the
amount of waste associated with this industry is also increasing. In order to reduce the
environmental impact and increase the efficiency of available resources, scientists around the
world are looking for ways to use recycled polymers. As the mechanical properties of
thermoplastics deteriorate with recycling, their range of applications is significantly narrowed.
In order to improve the mechanical performance of recycled polymers, they are reinforced with
lignocellulosic fibers.
Based on multiple studies, it is known that composites based on polyolefin and lignocellulose
are characterized by poor adhesion, forcing the surface modification of natural fibers before use.
Chemical treatments can be based on reactions involving esterification methods like acetylation
and benzylation, graft polymerization methods like treatments with triazine, isocyanates and
maleic anhydride, silane coupling agents, other treatments include alkali, acrylation and
acrylonitrile, permanganate, peroxide treatments and also steric acid, sodium chloride and
oleoyl chloride. Surface modification of fibres reduces its moisture absorption tendency and
improves their mechanical properties thereby increasing durability of the composites [1].
Recycled polypropylene and polyethylene are used as the matrix in this study. Buckwheat straw
was chosen for reinforcement of the composite, as this agricultural crop is quite widespread on
the territory of Latvia. In recent years there is a tendency to increase the area under buckwheat,
for example, in 2022 the area of buckwheat fields increased from 15-20 thousand to 30 thousand
hectares. Also, the possibilities of using this crop are little studied, although considering the
rather high percentage of cellulose content (on average 38%) there are prospects.
Silanization was chosen as the surface modification method because silane has an excellent
tendency to increase the hydrophobicity of the straw and perspective improve compatibility with
pololefin matrix. FTIR, DSC, TGA, rheology, wetting angle test, mechanical performance test
(impact strength, tensile strength and flexural strength) were used to investigate the obtained
material.
Acknowledgment
This work was supported by the Latvian Council of Science in the framework of FLPP “Obtaining multi-functional
bio-based compatibiliser and its effect on the performance of recycled polymer composites with biomass
reinforcement”, lzp-2021/1-0347.
Reference
2. Samanth M., Bhat K.S. Sustainable Chemistry for Climate Action, 2023, 100034.

38
ACCELERATED WEATHERING TESTING EFFECTS ON THE
PROPERTIES OF POLY(3-HYDROXYBUTYRATE-CO-3-
HYDROXYVALERATE AND ITS BIOCOMPOSITES WITH RAPESEED
MICROFIBER
Madara Žiganova, Remo Merijs-Meri, Jānis Zicāns, Agnese Ābele, Ivans
Bockovs, Tatjana Ivanova
Institute of Polymer Materials, Riga Technical University, Riga, Latvia
The intensifying focus on environmental issues drives the demand for materials that exert
minimal stress on ecosystems. Persistence of non-degradable plastics coupled with the
challenges of landfill saturation and escalating water and land pollution concerns underscores
the need for alternative solutions. As plastic consumption continues to rise and waste disposal
capacities face strain, the importance of biodegradable plastics and plastic waste sustainable
degradation has gained substantial attention.
Biodegradable polymers have emerged as a significant alternative to traditional plastics, which
impose long-term environmental pollution. In contrast to conventional polymers, poly(3-
hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is susceptible to biological degradation.
Microorganisms naturally convert PHBV into elemental components, minimizing its
environmental impact.
In this study, we investigate the behavior of PHBV polymer compositions reinforced with two
types of fibers, treated by either mercerization or N-methylmorpholine N-oxide (nmmo). Our
objective is to assess the effects of accelerated weathering on the properties of PHBV and
PHBV/Rapeseed (RS) microfiber biocomposites. All developed samples were subjected to
accelerated weathering conditions, including water spray, UV exposure, and conditioning for
up to 500 hours. Our study aims to comprehensively evaluate how exposure to accelerated
weathering conditions affects the mechanical, thermal, and other properties of these
biocomposites. These insights provide valuable information about their potential durability and
suitability for diverse applications.
Based on DSC analysis, the PHBV/RS biocomposite samples exhibited increased crystallinity.
In accordance with Montagna et al. this phenomenon was attributed to the influence of UV
radiation, which could have affected the amorphous regions of PHBV, causing chain breakage
followed by recrystallization of shorter chains. Mechanical testing results indicated that the
inclusion of RS microfibers significantly increased the material's mechanical strength while
preserving its flexibility in spite of increased degradation level, as confirmed by means of
carbonyl index (COi) measurements by Fourier transformed infrared spectroscopy.
References
1. Wei L., McDonald A. G. Accelerated weathering studies on the bioplastic, poly(3-hydroxybutyrate-co-3-
hydroxyvalerate)// Polym. Degrad. Stab.−2016.−Vol. 126, −P. 93-100,
https://doi.org/10.1016/j.polymdegradstab.2016.01.023
2. Antunes A, Popelka A, Aljarod O, Hassan MK, Kasak P, Luyt AS. Accelerated Weathering Effects on Poly(3-
hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and PHBV/TiO2 Nanocomposites. // Polym. J. – 2020. – Vol. 12, No.
8 – P.1743. https://doi.org/10.3390/polym12081743.
3. Montagna, L. S., Montanheiro, T. L. do A., Borges, A. C., Koga-Ito, C. Y., Lemes, A. P., & Rezende, M. C. Influence of
photodegradation with UV radiation in biotreatment with Paecilomyces variotti on PHBV/GNS nanocomposites. //IET
Nanobiotechnol.− 2018.−Vol.12, No. 3, −P. 285–291. https://doi.org/10.1049/iet-nbt.2017.0020

39
CHANGES IN RECYCLED PLASTICS AND POTENTIAL OF
MICROPLASTIC FORMATION DUE TO UV IRRADIATION
L. O. Vasiļjevs1,2, E. Kuka1, D. Cirule1, I. Andersone1, B. Andersons1
1Laboratory of Wood Biodegradation and Protection, Latvian State Institute of Wood Chemistry, Riga, Latvia
2 Faculty of Chemistry, University of Latvia, Riga, Latvia
Plastics after prolonged exposure to UV irradiation start to degrade via photooxidative aging
including free radical formation, oxidation, chain scission and/or crosslinking reactions. These
chemical changes cause loss in mechanical strength, increase in hygroscopicity, surface
embrittlement, and eventually surface erosion. The eroded particles are microplastics (MPs),
which have been identified as a major threat to the environment and its inhabitants. In general,
photodegradation of virgin plastics has been studied extensively, but there is not much literature
on the degradation of recycled plastics. Recycled plastics quite possibly could have higher risk
of producing MPs during degradation due to partial oxidation, contaminants and fragmented
chains in their structure (Müller et al. 2021). This is especially important in the light of
commitments (e.g. EU’s Plastic Strategy) that promote recycling and reuse of plastic. Recycled
plastics are widely used in such materials as wood plastic composites, which are exposed to
harsh conditions during their use and can be a significant source of MPs. The goal of the study
was to investigate the changes in recycled plastics caused by photodegradation and assess the
potential risks of MPs formation. Plastic granules of one LDPE, two HDPE, and two PP recycled
from different products were analysed. UV irradiation was performed in an accelerated
weathering chamber for milled (< 400 µm) plastic powder to ensure homogeneous changes
throughout the sample. Chemical and physical properties were investigated by ATR-FTIR, ICP-
MS, DSC, TGA, and element analysis. Formation of microcracks was studied on plastic
granules by SEM. The degradation of recycled plastics significantly differed between each
other. After 500 h UV exposure, LDPE and one of the PP samples showed a significant increase
in carbonyl index, O/C ratio as well as decrease in thermal stability indicating of plastic
oxidation and degradation. Impact was observed also on the polymer crystallization
characteristics, although the direction of the change was dependant on the plastic type. The other
PP and one of the HDPE samples showed first signs of degradation only after 1000 h UV
exposure. The other HDPE sample showed no noticeable changes in its properties. This plastic
had also the highest amount of heavy metals detected by ICP-MS. The SEM revealed
fragmentation on the surface for samples, which had noticeable degradation identified by other
methods. These plastics have also the highest potential of MPs formation.
Acknowledgment
The authors gratefully acknowledge the financial support by the Latvian Council of Science, project No. lzp-
2022/1-0639 “Study of microplastics formation from wood plastic composites and evaluation of prevention
possibilities (MicroWPC)”.
Reference
1. Müller C. Front Mar Sci 2021, 8:1–25.

40
EFFECTS OF MODIFICATION CONDITIONS ON STARCH ESTERS
PROPERTIES
Laura Peciulyte1, Jonas Luneckas1, Joana Bendoraitiene1, Ramune Rutkaite1
1Department of Polymer Chemistry and Technology, Kaunas University of Technology, Kaunas, Lithuania
Biodegradable polymers represent a solution to the problems of contamination caused by
conventional synthetic polymers. For this purpose, starch is considered as one of the most
promising materials because of its biodegradability, low price and renewability [1]. However,
the inefficiency of starch in processability due to the existence of hydrogen bonding interactions
and intermolecular forces impedes its applications. The replacement of starch hydroxyl groups
by ester groups can reduce number of hydrogen bondings and increase molecular mobility at
the same time by decreasing glass transition temperature and increasing hydrophobicity. The
aim of this study was to synthesize thermoplastic starch esters and investigate the influence of
modifying agent and substitution degree (DS) on the properties of modified starches.
In the first reaction stage potato starch was modified with octenyl succinic or dodecenyl succinic
anhydrides. Subsequently, in the second stage the anhydride modified starches were additionally
reacted with acetic anhydride. The obtained starch derivatives were characterized using Fourier-
transform infrared spectroscopy, differential scanning calorimetry and thermogravimetric
analyses. The changes in hydrophobicity of the derivatives were assessed by measuring the
water wetting angle of the derivative surface.
In order to assess the changes of granular structure the derivatives have been examined by
scanning electron microscopy. As shown in Fig 1 destruction of granules occurred during starch
derivatives (dodecenylsuccinate or octenylsuccinate) modification with acetic anhydride at
higher degree of substitution.
Fig. 1 Scanning electron microscope imagines (500x) of native starch (a), starch dodecenylsuccinate with
DSDDSA=0.02 (b), starch acetate dodecenylsuccinate with DSDDSA=0.02, DSAc=0.38 (c) and starch acetate
dodecenylsuccinate with DSDDSA=0.02, DSAc=1.87 (d)
It was revealed, that destruction temperature of starch derivatives depended the anhydride used
for modification and on the degree of substitution. When starch was modified with octenyl
succinic or dodecenyl succinic anhydrides at low degree of substitution the glass transition (Tg)
temperature was not observed. In the case obtained starch derivatives were additionally
modified with acetic anhydride the Tg depended on degree of acetylation. Moreover, the Tg for
those dually modified starches was also observed at lower degree of substitution compared to
those of acetic anhydride modified starch.
References
1. Nasseri, R.; Moresoli, C.; Yu, A.; Yuan, Z.; Xu, C. C. Structural Dependence of the Molecular Mobility in Acetylated Starch // Polymer –
2021. Vol. 215, P. 1–9.

41
ACTIVE PAPER COATINGS CONTAINING ESSENTIAL OILS AND
THEIR COMPONENTS
Vesta Navikaite-Snipaitiene1, Kamile Spirikavice1, Ramune Rutkaite1,
Emilija Galkauskaite1, Jurate Siugzdaite2, Egle Beatrice Grigonyte2
1Department of Polymer Chemistry and Technology, Kaunas University of Technology, Kaunas, Lithuania
2Department of Veterinary Pathobiology, Lithuanian University of Health Science, Kaunas, Lithuania
Currently, interest in the production of active packaging using renewable and environmentally
friendly materials is growing. Active packaging has been shown to extend the shelf life of food
products and reduce the growth rate of certain microorganisms. Essential oils have long been
recognized for their antibacterial, antifungal, and antioxidant properties. Due to the instability
of essential oils, they cannot be directly added into the food packaging and require
immobilization [1]. In this study, the clove essential oil (CL) eugenol (EU) and cinnamon
aldehyde (CI) were immobilized in starch sodium octenylsuccinate (SSO). The obtained
emulsions were applied on paper and bioactive properties such as antioxidant and antimicrobial
activities of the coatings have been evaluated.
The aqueous emulsions consisting of 20 % (w/v) of SSO and 2.5, 5 or 10 % (w/w) of CL, EU
or CI were prepared by using rotor-stator homogenizer. The coatings were obtained by casting
the emulsions on paper. The antioxidant and antimicrobial activities of coated paper samples
were assessed by using 2,2-diphenyl-1-picrylhydrazyl and disc diffusion methods, respectively
(Table 1). The antioxidant properties evaluation revealed that high antioxidant activity reaching
76-92 % and 87-91 % was characteristic of CL and EU emulsion coatings, respectively.
Meanwhile, coatings containing CI showed quite low antioxidant activity (4-9 %). However, it
was established that paper coated with 10 % of CI emulsion had a greatest antimicrobial effect
on studied microorganisms.
Table 1. Antioxidant and antimicrobial activity of paper coatings
Sample
Antioxidant activity (%)
Inhibition zone (mm)
C. albicans
S. aureus
E. coli
B. cereus
C-CL-2.5
76 ± 1.9
n
n
n
n
C-CL-5
90 ± 0.1
n
n
n
8.06
C-CL-10
92 ± 0.3
8.42
n
9.43
8.70
C-EU-2.5
87 ± 0.4
n
n
n
8.03
C-EU-5
91 ± 0.4
n
n
8.70
8.49
C-EU-10
91 ± 0.5
10.81
n
9.94
10.41
C-CI-2.5
4 ± 0.5
10.82
n
n
7.57
C-CI-5
5 ± 2.2
13.61
n
13.20
17.08
C-CI-10
9 ± 3.0
15.50
10.82
18.71
18.32
n – no inhibition zone detected
In conclusion, the clove essential oil and eugenol emulsions could be used as effective natural
antioxidants, whereas cinnamon aldehyde emulsions as antimicrobial agent in food packaging
systems aiming to improve the quality and extend the shelf life of selected food products.
Acknowledgements
The research was performed in the frame of the COST Action CA19124.
Reference
1. Carpena, M., Nuñez-Estevez, B., Soria-Lopez, A., Garcia-Oliveira, P., Prieto, M.A. Essential oils and their
application on active packaging systems: A Review // Resources – 2021. – Vol. 10, No. 7 – P. 1–20.

42
EFFECT OF DIFFERENT MODIFIED CARDANOL COMPOUNDS ON
THE MECHANICAL AND CLIMATIC RESISTANCE PROPERTIES OF
THE MATERIAL
R. Bērziņš1, A. Ābele1, J. Zicāns1, R. Merijs-Meri1, O. Kabat2, V. Sytar2
1Institute of Polymer Materials, Faculty of Materials Sciences and Applied Chemistry, Riga Technical University,
3 Paula Valdena street, Riga, LV-1048, Latvia
2Department of Innovation Engineering, Ukrainian State University of Chemical Technology, 8 Gagarina str,
Dnipro-City, 49005, Ukraine
Cardanol derivatives are widely used in various coatings because it has very good resistance to
different climatic environments [1]. Cardanol is a renewable natural resource that is an excellent
precursor for various syntheses, yielding a wide variety of materials with various applications
[2]. Despite the fact that prepolymers for polyurethane systems have been developed [3], silyl-
terminated prepolymer systems, which are in great need of protection in aqueous environments,
have not been studied because their structure is typically made of polyether chains, which have
poor water resistance.
Cardolite Ultra Lite 513, an
epoxidized cardanol product, was
used during the work, which was
modified with two different
secondary amine silanes, changing
the functionality of the prepolymer
(Fig 1).
OO
C7H14 CH3
+
H9C4NH
C3H6Si
OCH3
OCH3
OCH3
O
C7H14 CH3
NC2H4
C4H9
Si OCH3
OCH3
OCH3
OH
R1
R2NH
Si Si
H3CO
OCH3
OCH3
OCH3
OCH3
OCH3
R1R2
or
Fig 1. Modified cardanol compound synthesis
As the functionality increases, the cross-
linking of the materials increases, as a
result, the deformation properties of the
materials decrease (Fig 2). Modified
cardanol-type prepolymers increased the
climatic resistance (combination of UV
light, temperature (60 oC) and water) of
materials by .15% when add 10% of
cardanol based prepolymer.
Fig 2. Dependence of material deformation on
cardanol prepolymer content
Acknowledgement
The research was performed in the frame of the Latvia-Ukraine cooperation research, LV_UA /2023/8
References
1. E. Darroman, N. Durand, B. Boutevin, S. Caillol. 2019, vol 2016, pp 6-19;
2. K. Suresh, S. V. Kishanprasad. Ind. Eng. Chem. Res. 2005, vol. 44, pp 4504–4512;
3. D. Balgude, A. Sabnis, S. K. Ghosh.. European Polymer Journal, 2016, vol 85, pp 620-634.
0.0
200.0
400.0
600.0
020 40
εbreak, %
Cardanol derivate concentration %
Cardanol_
Dynasylan
1189
Cardanol_
Dynasylan
1122

43
EFFECT OF SILYL-TERMINATED CARDANOL AND DIFFERENT
FILLERS ON CURING DYNAMICS AND MECHANICAL PROPERTIES
OF POLYETHER-BASED SILYL-TERMINATED PREPOLYMER
R. Bērziņš1, A. Ābele1, J. Zicāns1, R. Merijs-Meri1, O. Kabat2, V. Sytar2
1Institute of Polymer Materials, Faculty of Materials Sciences and Applied Chemistry, Riga Technical University,
3 Paula Valdena street, Riga, LV-1048, Latvia
2Department of Innovation Engineering, Ukrainian State University of Chemical Technology, 8 Gagarina str,
Dnipro-City, 49005, Ukraine
Practically all industries are looking for opportunities to use raw materials that can be obtained from
nature. Among the materials that are already used in different forms are cardanol-based compounds,
because they affect different properties of the material, such as resistance against water and oxidative
stability, which are very important for materials used in outdoor conditions. However, real adhesive
systems are not only composed from polymers, largest part of the composition of the adhesive
consists of fillers (w=40-80%), thus reducing their price, improving processability, as well as in
many cases increasing climatic resistance, so it is important to understand how they will change the
curing and mechanical properties of the system.
The commercial SAX 520 used in the study has a linear structure that requires structuration by
particles, otherwise the polymer will form lumps during curing and will not develop its maximum
possible properties. The obtained results of the mechanical properties in tension showed that the
addition of modified calcium carbonate increases both the tensile strength (by 25%) and the
deformation (by 15%). Silyl-terminated cardanol prepolymer was synthesized from epoxidized
cardanol with trade name Cardolite Ultra Lite 513 and secondary amino silane (Fig. 1).
Fig 1. Synthesis of modified cardanol compound
Integration of the synthesized prepolymer in the composition of the two-component adhesive
increased both the material’s elasticity and tensile deformation by increasing the silyl-terminated
cardanol concentration (Fig. 2). Modified cardanol prepolymer significantly affected the curing
dynamics of the SAX 520 by accelerating the hardening.
Fig 2. Changes in tensile strain depending on the concentration of modified cardanol
Acknowledgement
The research was performed in the frame of the Latvia-Ukraine cooperation research, LV_UA /2023/8

44
INFLUENCE OF LONG-TERM STORAGE AND UV LIGTH EXPOSURE
ON RIGID PU FOAMS’ CHARACTERISTICS
Beatrise Sture, Vladimir Yakushin, Ugis Cabulis
Polymer Laboratory, Latvian State Institute of Wood Chemistry, Riga, Latvia
Rigid polyurethane (PUR) foams is the most effective insulation material used in space
launchers since the beginning of cryogenic fuel use, due to their outstanding thermal and
mechanical properties. The Latvian State Institute of Wood Chemistry has been cooperating
with the aerospace industry for a long time in developing cryogenic insulation for its specific
requirements. The current requirements for materials used in space are the same as conventional
materials, i.e. they must be environmentally friendly, non-toxic, and at the same time, the
European Space Agency recommends using raw materials produced in Europe. In previous
studies PUR foam formulations containing the 4th generation blowing agent HFO-1233zd, under
trade name Solstice® LBA [1] and amine-based catalysts [2] were developed. This resulted in
production and future development of low-density PUR foams as cryogenic insulation.
In this study, spray-applied PUR foams using different ratios of amine-based catalysts were
produced. Due to climate changes, several restrictions have been made towards usage of
blowing agents used for rigid PU foam production. Until this century mostly hydrofluorocarbons
(HFCs) were used for foam production, but it was found out that HFCs are of high global
warming potential (GWP). Therefore, Kyoto Protocol in accordance with the United Nations
Framework Convention on Climate Change (UNFCCC) and the European Parliament’s
developed regulations, have suggested hydrofluoroolefins (HFOs) as an alternative for rigid PU
foam production due to their low GWP and ozone depletion potential (ODP). The change of
blowing agents naturally altered the usage of catalysts.
Reactive amine-based catalysts are less hazardous because of their low volatility and ability to
react successfully with isocyanate or polyols. Spray-applied rigid PU foams with potential
application for cryogenic insulation were produced and tested for long-term storage analyzing
parameters such as pH value of polyol composition, foaming kinetics (trise, tcream) etc. Thermo-
mechanical analysis (TG, DSC) was also acquired of developed materials, as well as artificial
ageing by exposing samples to UV light.
It was discovered that PUR foams obtained using reactive amine-based catalysts, such as
Polycat 203 and 218, have higher integral heat capacity, but polyol mixtures containing these
catalysts cannot exceed storage time for more than 4 months. It was also observed from artificial
ageing tests of PUR cryogenic insulation by exposing to UV light that thickness of degraded
layer reached 0.8 mm (after 1000 h), but no significant destruction of cellular structure deeper
in material was observed.
References
1. Yakushin, V., Rundans, M., Holynska, M., Sture, B., Cabulis, U. Influence of Reactive Amine-Based
Catalysts on Cryogenic Properties of Rigid Polyurethane Foams for Space and On-Ground Applications //
Materials – 2023. – Vol. 16 – P. 2798-2812.
2. Yakushin, V., Rundans, M., Holynska, M., Sture, B., Cabulis, U. Influence of Reactive Amine-Based
Catalysts on Cryogenic Properties of Rigid Polyurethane Foams for Space and On-Ground Applications //
Materials – 2023. – Vol. 16 – P. 2798-2812.

45
ELECTROSPUN FIBROUS MEMBRANES FOR TATTOO WOUND
CARE
Zane Zelca1, Kristine Pavlovica1, Aigars Reinis2
1 Institute of Design technology, Faculty of Materials Science and Applied Chemistry, Riga Technical University,
Kipsala street 6A, LV-1048, Riga, Latvia;
2 Department of Biology and Microbiology, Riga Stradins University, Dzirciema street 16, LV-1007, Riga, Latvia
In the process of tattooing, wounds are created that require specific care to protect the wound,
reduce the formation of scabs and not damage the visual appearance of the tattoo. Electrospun
polymer nano and micro-size fibrous membranes can be used as materials for various
applications including wound care and as a transdermal drug delivery system. The study aims
to evaluate the suitability of electrospun membranes for tattoo wound healing and care. Each
electrospun multilayer composite layer has a different active component (Brazilian green
propolis, Aloe Vera extract, or Dermobacter). Polyvinyl alcohol is safe for humans which makes
it a great base polymer for healing wounds combined with bioactive additives. The fibrous
membranes are manufactured with Nanospider electrospinning equipment using a rotating
cylinder electrode. Thickness, tensile properties, fibers diameters, membrane morphology, air
permeability, antimicrobial properties, and solubility were measured to assess suitability for
wound care. The study also analyzed the effect of membranes on the color of tattoo pigments to
evaluate suitability for tattoo wound healing.
The obtained in vitro results show that fiber membranes can be used as antibacterial and
antifungal materials against P.aeruginosa, E.coli, S.aureus, and Candida. The sample's
solubility depends on additives (from 6 milliseconds to 10 minutes) and therefore, active
substances released to the wound can be planned and predicted. There was no significant effect
of active substances on tattoo pigments observed. The developed nanofiber membranes have
potential for the application of bioprotection and may provide a microenvironment for medical
treatment and care, bioactive delivery systems, wound protective layers, and elsewhere. In vivo
tests are needed in the future to determine the effectiveness of membranes in wound healing and
care.

46
THE EXTRACTED BIRCH OUTER BARK AS A FILLER FOR WOOD-
PLASTIC COMPOSITE
G. Shulga1, B. Neiberte1, A. Verovkins1, J. Rizhikovs2, A. Paze2, S. Vitolina1,
T. Betkers1
Laboratory of Lignin Chemistry 1 and Biorefinery Laboratory2, Latvian State Institute of Wood Chemistry,
Dzerbenes 27, 1006 Riga, Latvia
The birch outer bark is rich in extractives, which can be isolated in good yields with organic
solvents. After the extraction, birch outer bark contains up to 45% (dry basis) of suberin. Thus,
the remaining biomass can still be used to produce other high-added-value products.
The research will be conducted on the use of the extracted birch outer bark as a filler in a wood-
plastic composite. The bark residue was obtained as a result of betulin (a non-aromatic diol with
a pentacyclic ring structure) extraction. The binary polymer blend from recycled polypropylene
(rPP) and polylactic acid (PLA) in the defined mass ratio was used as a polymer matrix. The
samples were prepared with a filling degree from 10 to 50 wt. % by extrusion and moulding,
using HAAKE MiniLab II and MiniJet devices. The study evaluated the following parameters:
(1) filling degree; (2) extracted bark particle size; 3) coupling agent (4) lubrication.
It was found that a 10 wt% content of the bark particles in the composite slightly increased its
mechanical properties. With an increase in the degree of filling, the mechanical properties of
the composite deteriorated regardless of the filler particle size. In order to improve the
compatibility between the polymer matrix and the extracted bark microparticles, Licocene PP
MA 7452 as a coupling agent was used. According to the obtained results, a 3% content of the
coupling agent in the composite led to a remarkable increase in the mechanical strength and
modulus, regardless of the degree of filling and the size of bark particles. With an increase in
the bark particle sizes, the tensile and bending strength values and contact angles of the
composite samples decreased. The presence of suberinic acids in the extracted birch outer bark,
performing a lubricant function, improved the processing parameters of the obtained composite
from the point of view of energy consumption.
Acknowledgement
This work was carried out due to the financial support from the Base Financing provided by the Latvian Ministry
of Education and Science for the Biogrant 3-2022 and partly funded by “BarkBuild– Tree bark as a renewable
source of wood protection materials for building applications (ES RTD/2022/14 within ERA-NET Cofund Action
“ForestValue – Innovating the forest-based bioeconomy”).

47
OPTIMIZATION OF MICROENCAPSULATION OF ISOPHORONE
DIISOCYANATE IN POLYUREA SHELL
L. Pastarnokienė1, T. Kochanė1, E. Potapov1, R. Makuška1
1Department of Polymer Chemistry, Faculty of Chemistry and Geosciences, Vilnius University, Vilnius,
Lithuania
In the present environmental context, there is considerable interest in self-healing materials. The
integration of self-healing microcapsules into coatings holds promise for waste reduction by
extending the lifespan of these products through the repair of cracks and scratches that occur
during their usage [1]. To effectively fulfill their intended purpose, microcapsules must possess
specific dimensions, maintain structural integrity throughout storage, formulation, and coating
application processes, contain an adequate quantity of healing agents, and readily rupture upon
coating damage without compromising the mechanical properties of the surrounding matrix [2].
Isocyanates can be very effective in self-healing systems because of reactivity towards polyols,
amines and aspartic acid esters, or even form a coating on their own due to partial hydrolysis to
amines in moist environment. Isocyanates can be encapsulated in many different shells
including polyurea, poly(urea-formaldehyde), poly(melamine-formaldehyde), and polyurethane
[3].
This study was focused on encapsulation of isophorone diisocyanate into polyurea shell using
interfacial polymerization method. Four key parameters (core-to-shell ratio, agitation speed,
type of emulsifier, and reaction time) that have the potential impact on the core content and size
of the microcapsules were tested. The Taguchi design methodology was utilized to determine
the optimal process parameters through the use of signal-to-noise ratio analysis. Larger-the-
better criterion was used to identify the optimal conditions to achieve the maximum core
content, while the nominal-the-better criterion was used to determine the parameters that were
most effective in producing microcapsules of desirable size. Various analysis methods (FT-IR
spectroscopy, optical and scanning electron microscopy, TGA analysis) were employed to
investigate the effects of different parameters on properties of the microcapsules.
The optimal conditions to get the highest amount of isophorone diisocyanate inside polyurea
shell were achieved by using gum arabic (7 %) as emulsifier, core to shell ratio 4:1, agitation
speed 3000 rpm and reaction time of 60 mins. The optimal microcapsule size of around 50 µm
was achieved by using a mixture of poly(vinyl alcohol) (2 %) and gum arabic (3 %) as an
emulsifier, core to shell ratio 4:1, agitation speed 5000 rpm, and reaction time of 45 min.
Acknowledgements
The study was supported by the project of the EU funds investment tool “Eksperimentas” „Polyaspartic coatings
without volatile organic compounds for wooden surfaces“, No 13.1.1-LVPA-K-856-01-0104.
References
1. Utrera-Barrios S., Verdejo R., López-Manchado M., Hernández Santana M. Evolution of self-healing
elastomers, from extrinsic to combined intrinsic mechanisms: a review // Materials Horizons – 2020. – Vol. 7,
No 11 – P. 2882–2902.
2. Nesterova T., Dam-Johansen K., Kiil S. Synthesis of durable microcapsules for self-healing anticorrosive
coatings: A comparison of selected methods //Prog. Org. Coat. – 2011. – Vol. 70, No 4 – P. 342-352.
3. Yang J., Keller M. W., Moore J. S., White S. R., Sottos N. R. Microencapsulation of isocyanates for self-
healing polymers //Macromolecules – 2008. – Vol. 41, No 24 – P. 9650-9655.

48
DEVELOPMENTS OF POLYURETHANE CRYOGENIC INSULATION
MODIFIED WITH PHASE CHANGE MATERIALS
Ugis Cabulis1, Laima Vevere1, Beatrise Sture1, Vladimir Yakushin1
1Polymer Laboratory, Latvian State Institute of Wood Chemistry, Riga, Latvia
Poyurethanes (PUR) are used as structural materials e.g. in cryogenic insulation and sandwich
structures for space applications. The Ariane 6 space launcher will use cryogenic propellant
engines in its main and upper stage and perfect insulation of cryogenic hydrogen and oxygen
tanks there is the task to be solved. Usage of thermo-regulative phase change material (PCM)
doped polyurethane (PU) foam (PUR-PCM) as a cryogenic insulation in liquefied gasses fuel
tanks can promote energy saving in terms of cooling load reduction through utilizing its mutual
advantage of insulation as well as adhesion characteristics of foam layer at cryo-schock
conditions. The solid-solid or solid-liquid PCMs are mainly classified as inorganic,
organic, eutectic.
CrodaTherm ME29P as an acrylic core shell particle powder was used as potential PCM for
PUR-PCM composites. As ingredients for A-component is used polyols obtained from
renewable resources, like as rape seed oil or tall oil, and the 4th generation blowing agent
Solstice®LBA (HFO 1233zd) – material with low Global warming potential (GWP).
This research presents the properties of PUR foams modified with PCM obtained at a laboratory
scale with potential to be up-scaled. The properties of the foams were also compared in relation
to the method used for their production. Also different primers were modified with PCMs with
idea to improve adhesion between metal, in our case aluminium and PUR cryogenic insulation.
Low density cryogenic PUR foams modified with PCM using the 4th generation blowing agent
Solstice®LBA were developed. Using the optimal catalyst system for Solstice®LBA blowing
agent in appropriate concentrations, it is possible to obtain foam with a density lower than 35
kg/m3 and at the same time with a bond strength after cryoshock higher than 0.3 MPa and a
safety coefficient higher than 3. The research shows the possibility that by combining more
environmentally friendly catalysts and PCM it is possible to obtain PUR material, which in the
future can serve as cryogenic insulation in liquefied natural gas (LNG) transportation or in space
technologies.

49
PHLOROGLUCINOL-BASED SHAPE-MEMORY POLYMERS
Auksė Navaruckienė, Aušrinė Pabricaitė, Jolita Ostrauskaitė*
Department of Polymer Chemistry and Technology, Kaunas University of Technology, Kaunas, Lithuania
*Correspondence: jolita.ostrauskaite@ktu.lt
Shape memory polymers have a unique ability to obtain temporary shapes and return to their
permanent shape in response to stimuli such as temperature, pH, light, electricity, microwave,
solvent or ultrasound [1, 2]. Such polymers can be used in various applications such as medical
smart devices, sensors, conductive electronics and etc. [3].
The aim of this work was to design and synthesize novel phloroglucinol-based shape- memory
photopolymers and investigate their properties. The synthesis of phloroglucinol-based cross-
linked polymers with three different biobased comonomers, phloroglucinol, 1,4-
cyclohexanedimethanol and dianhydro-D-glucitol, was performed by cationic
photopolymerization. Real-time photorheometry was used to monitor the evolution of the
photocuring process. The storage modulus (G’), the loss modulus (G”) and the complex
viscosity (η*) were recorded as a function of the irradiation time. The chemical structure of the
obtained polymers was confirmed by Fourier transform infrared spectroscopy and Soxhlet
extraction. Mechanical and thermal properties of polymers were investigated by tensile test,
dynamical mechanical thermal analysis and thermogravimetric analysis. It was determined that
rheological, thermal and mechanical properties depended on the amount and type of
comonomer.
The thermo-responsive shape memory properties of phloroglucinol-based polymers were
determined by their glass transition temperature (Tg from 33 to 67 °C). The polymer samples
were heated above their glass transition temperature, deformed to the desired temporary shape
and fixed by cooling the polymer sample below its Tg. All polymer samples were able to return
to their permanent shape in a short period of time after heating above their Tg.
Acknowledgement
This research was funded by the Research Council of Lithuania (project No. S-MIP-23-52).
References
1. Xia Y., He, Y., Zhang, F., Liu, Y., Leng, J. A Review of Shape Memory Polymers and Composites:
Mechanisms, Materials, and Applications // Adv. Mater. – 2021. – Vol. 33, No. 6. 2000713.
2. Ezati P., Khan A., Priyadarshi R., Bhattacharya T., Tammina S.K., Rhim J.W. Biopolymer-based UV
protection functional films for food packaging // Food Hydrocoll. – 2023. – Vol. 142. 108771.
3. Pilate F., Toncheva A., Dubois P., Raquez J.M. Shape-memory polymers for multiple applications in the
materials world // Eur. Polym. J. – 2016. – Vol. 80. 268-294.

50
PROTEASE PRODUCTION FROM E. COLI BL21(DE3)-PET32A-ASP
AND ITS APPLICATION IN LEATHER DEHAIRING
Renata Biškauskaitė1, Wen-Chien Lee2, Virgilijus Valeika1
1Department of Polymer Chemistry and Technology, Kaunas University of Technology, Kaunas, Lithuania
2 Department of Chemical Engineering, National Chung Cheng University, Chia-Yi, Taiwan R.O.C.
Proteases are one of the largest family of enzymes, which are divided into groups based on
reaction mechanisms, site of action and active site structure [1]. Due to the high variety,
proteases have a wide application in different industries such as leather, food and feed,
detergent, chemical industry, waste management, medical field, etc. In leather industry, protease
receives more attention because of its activity on non-collagenous proteins; these enzymes can
be suitable for soaking, bating, dehairing [2]. This investigation aims to produce protease from
recombinant E. coli BL21(DE3)-pET32a-asp and study its application in hide dehairing. After
bacterial enzyme cultivation, protein concentration, molecular mass, caseinolytic and
keratinolytic activity were evaluated. The crude enzyme (extracellular protease) was applied for
dehairing to evaluate the possibility of enzyme use in leather processing. SDS-PAGE showed
protein molecular masses and its changes during the induction. The caseinolytic and
keratinolytic activity of the obtained product showed high specific activity toward the substrates.
Although the extracellular protease of recombinant E. coli had a high specific activity, the
enzyme concentration was too low to obtain any effect on the hide during dehairing.
References
1. Ward O. P. Proteases // In: Comprehensive Biotechnology/ Ed. by M. Moo-Young – Oxford, Pergamon,
2011. –571-582 p.
2. Razzaq A., Shamsi S., Ali A., Ali Q., Sajjad M., Malik A., and Ashraf M. (2019). Microbial proteases
applications // Front. in Bioeng. and Biotech. – 2019. – Vol. 7, No. 110.

51
SYNTHESIS AND STUDY OF AZO GROUP CONTAINING POLYMERS
Shushanna Vardanyan1, 2, Narine Durgaryan1, 2, Juozas Gražulevičius2
1Department of Organic chemistry of Yerevan State University, Alex Manoogian 1, 0025, Yerevan, Armenia
2Department of Polymer Chemistry and Technology, Kaunas University of
Technology, K. Baršausko st. 59, LT-51423, Kaunas, Lithuania
shushanna.vardanyan@ysu.am
A copolymer of trimer and pentamer, obtained by diazotization of m-phenylenediamine and azo
coupling with m-phenylenediamine, was prepared with aniline and anisidine in molar ratios of
1:10, 1:20, 1:40 with ammonium persulfate, taken in a molar ratio of 1:0.8 in calculation for
amino groups: The structures of the obtained polymers are confirmed by spectral methods NMR,
UV-spec. It is shown that soluble polymers are obtained, the content of aniline or anisidine
groups in their structure increases with an increase in their content in the initial mixture. It is
shown that the high electrical conductivity of the obtained polymers is due to the content of
quinonediimine groups in the structure. An electron-withdrawing model compound was also
obtained by diazotization of the trimer and conjugation with quinoline.
Acknowledgement
The research was funded by the European Union’s Horizon 2020 Research and Innovation Programme under the
Marie Skłodowska-Curie grant agreement No. 823720.
Keywords: Conductive polymers, diazotation, azocoupling, copolymerisation, azo-group.
References
1. S. Tamulevičius et al. Experimental Techniques 34(1) p. 55-62 (2010)
2. Wang, Xiaogong. Azo Polymers. Springer Berlin Heidelberg, (2016)
3. Timpu D. et al. J. Optoelect. Adv. Mater., v. 2, p. 531-535, (2000)
4. Tam, Teck Lip Dexter, and Jianwei Xu.,Journal of Materials Chemistry A 9, no. 9 5149-5163 (2021)
5. Chomicki D. et al., Polymers. International Journal of Molecular Sciences.; 21(16), 5755. (2020)
6. Acevedo, Diego F., et al. Electrochimica acta 56.10, p. 3468-3473 (2011):
7. Vardanyan Sh., Durgaryan R., Synthesis and study of oligomers containing azo-groups, Collection of
scientific articles of YSU SSS 1.3(29), p. 179-185 (2019)

52
MEASUREMENT OF THERMAL CONDUCTIVITY OF CARBON FIBER
REINFORCED LAMINATES BY TRANSIENT PLANE SOURCE
METHOD
S. Tarasovs, A. Aniskevich
Institute for Mechanics of Materials, University of Latvia, Riga, Latvia
Determination of the in-plane thermal conductivity of a thin unidirectional carbon fiber
reinforced lamina is a challenging task since most direct measurement methods use heat flowing
perpendicular to the surface of the sample. Indirect methods, like the laser flash method, can be
used for simultaneous measurement of both in-plane and through-the-thickness thermal
conductivity of composite laminates [1, 2]. In this work, the orthotropic thermal conductivity
properties of carbon fiber reinforced laminates were measured using the transient plane source
method combined with a numerical inverse solution.
Unidirectional and quasi-isotropic laminates were used for testing. A set of two measurements
with insulation and conductive blocks attached to samples were used to enhance the heat flow
in in-plane and through-the-thickness directions, respectively, and simplify the separation of
conductivity values in the fiber and transverse directions.
A numerical inverse solution technique was used for the identification of the orthotropic
conductivity tensor of a single unidirectional lamina using experimental temperature increase
curves from transient plane source measurements [3]. The proposed procedure was based on an
inverse solution of a transient heat diffusion problem in layered anisotropic laminates with a
finite element analysis used to solve the direct problem. An optimization procedure using
Nelder-Mead method was employed for the estimation of the best-fit thermal properties of
composite material.
Micromechanical analysis was used to estimate the axial and transverse thermal conductivity of
carbon fibers. A developed computer program was used to generate a two-dimensional periodic
representative volume element with the volume content of the fibers equal to 74% for the
estimation of effective thermal conductivity of a unidirectional composite in transverse
direction.
References
1. Bard S., Schönl F., Demleitner M., and Altstädt V. Influence of fiber volume content on thermal conductivity
in transverse and fiber direction of carbon fiber-reinforced epoxy laminates // Materials – 2019. – Vol. 12,
No. 7 – P. 1084.
2. Pawlak S., Tokarski M., Ryfa A., Orlande H. R., and Adamczyk W. (2022). Measurement of the anisotropic
thermal conductivity of carbon-fiber/epoxy composites based on laser-induced temperature field:
Experimental investigation and numerical analysis // Int. Commun. Heat Mass Transf. – 2022. – Vol. 139 –
P. 106401.
3. Tarasovs S. and Aniskevich A. (2023). Identification of the anisotropic thermal conductivity by an inverse
solution using the transient plane source method // Measurement – 2023. – Vol. 206 – P. 112252.

53
THERMORESPONSIVE PROPERTIES OF ACENAPHTHYLENE
LABELLED CHITOSAN GRAFT
POLY(N-ISOPROPYLACRYLAMIDE) COPOLYMERS
Migle Babelyte1, Ramune Rutkaite1, Vesta Navikaite-Snipaitiene1, Emilija
Morkvenaite1, Volodymyr Samaryk2
1Department of Polymer Chemistry and Technology, Kaunas University of Technology, Kaunas, Lithuania
2 Department of Organic Chemistry, Lviv Polytechnic National University, Lviv, Ukraine
Poly(N-isopropylacrylamide) (PNIPAAm) is one of the most attractive thermoresponsive polymers
that exhibits sharp solubility changes in water around a specific temperature which is well known
as the lower critical solution temperature (LCST). Recently, copolymers with grafted PNIPAAm
side chains are highly researched, taking into account their great opportunities in biomedical field
including drug delivery systems. One of the most perspective biopolymers which could be used as
backbone of the thermoresponsive graft copolymer is chitosan, because this natural polymer is
biodegradable, biocompatible and non-toxic. Moreover, acenaphthylene (ACE) could be also
introduced into PNIPAAm grafts and serve as a fluorescent marker for more detailed investigation
of thermoresponsive behavior of synthesized copolymers.
In this study, seven ACE labelled chitosan-graft-poly(N-isopropylacrylamide) (CS-g-PNIPAAm-
ACE) copolymers were synthesized by free-radical polymerization of CS, NIPAAm and ACE in
aqueous solution using potassium persulfate (PPS) as an initiator and By changing the molar ratio
of CS:NIPAAm:ACE from 1:0.25:0.0125 to 1:10:0.11 the ACE labelled copolymers with different
grafting ratio were prepared.
Fig1. Average particle diameter of CS-g-PNIPAAm-5-ACE in acetic acid solution versus temperature
behaviour
The obtained copolymers were characterized by FT-IR, and H-NMR spectroscopy. Furthermore, the
thermoresponsive behaviour of the prepared copolymers was investigated by cloud point, particle
size (see Fig.1.), differential scanning calorimetry and fluorescence spectroscopy analysis.
Moreover, the thermal properties of the copolymers were investigated by thermogravimetric
analysis.
Acknowledgment
The financial support of the Research Council of Lithuania for the project No. S-LU-22-11 in the frame of Lithuanian–Ukrainian
Cooperation Programme in the Fields of Research and Technologies is highly acknowledged.
0
100
200
300
400
500
600
700
800
20 25 30 35 40 45 50
Particle size, nm
Temperature, ºC

54
NEW HOLE-TRANSPORTING MATERIALS FOR ORGANIC
OPTOELECTRONICS BASED ON P-PHENYLENEDIAMINE
SKELETON FUNCTIONALIZED WITH SULFUR-CONTAINING
MOIETIES
Svetlana Sargsyan1, Mariia Stanitska2, 3, Melika Ghasemi2, Rasa
Keruckiene2, Dmytro Volyniuk2, Narine A. Durgaryan1, Juozas Vidas
Grazulevičius2
1 Department of Organic Chemistry, Yerevan State University, Alex Manoogian St., 1, Yerevan 0025
2 Department of Polymer Chemistry and Technology, Kaunas University of Technology, K. Baršausko st. 59, LT-
51423, Kaunas, Lithuania
3 Department of Organic Chemistry, Ivan Franko National University of Lviv, Kyryla i Mefodiya st. 6, Lviv,
Ukraine
svetlana.sargsyan@ysu.am
Hole transporting materials (HTMs) that are utilized in OLEDs have to be characterized by
high hole mobility values, suitable HOMO levels to ensure low energy barrier for hole injection
from the anode into the emissive layer, and a suitable LUMO level to prevent electron injection
from the emissive layer to the hole transport layer. In order to fulfill the abovementioned
requirements, organic HTMs typically have electron-donating moieties such as diphenylamine,
carbazole, etc. in their molecular structures [1]. The simplicity and cost-effectiveness of their
synthesis together with good thin film-forming properties and environmental friendliness makes
them advantageous over their inorganic counterparts.This work focuses on the synthesis of four
new HTMs that are based on sulfur-containing aromatic compounds. All the compounds were
obtained via Buchwald-Hartwig cross-coupling reactions in good yields. The ionization
potential (IP) values of the solid samples of the compounds were found to be in the range of
5.11-5.2 eV. The values of zero-field mobility µ0 were obtained in the range from 4.6×10-5 to
7.6×10-5 cm2/V∙s. Taking into account the low ionization potential and high hole mobility values
of the compounds, their films have potential to be used not only for preparation of hole-
transporting layers (HTLs) of OLEDs, but also for HTLs of perovskite solar cells.
Acknowledgement
The research was funded by the European Union’s Horizon 2020 Research and Innovation Programme under the
Marie Skłodowska-Curie grant agreement No. 823720.
Keywords: p-phenylendiamine, hole transporting material, OLED.
Reference
1. Swayamprabha, S. S., Nagar, M. R., Yadav, R. A. K., Gull, S., Dubey, D. K., & Jou, J. H. (2019). Hole-
transporting materials for organic light-emitting diodes: An overview. Journal of Materials Chemistry C,
7(24), 7144-7158.

55
DIBENZOTHIOPHENE AND TRIPHENYLAMINE DERIVATIVES AS
EMITTERS IN ELECTROLUMINESCENCE DEVICES AND OPTICAL
OXYGEN SENSORS
Melika Ghasemi1, Malek Mahmoudi1, Dalius Guedeika1, Karolis Leitonas1,
Jurate Simokaitiene1, Asta Dabuliene1, Alexander Panchenko2, Boris F.
Minaev2, Dmytro Volyniuk1, Juozas V. Grazulevicius1
1Department of Polymer Chemistry and Technology, Kaunas University of Technology, Kaunas, Lithuania
2Department of Chemistry and Nanomaterials Science, Bohdan Khmelnytsky National University, Cherkasy,
Ukraine
Organic luminophores with a donor and acceptor structure have garnered significant attention
for their potential application in organic light-emitting diodes (OLEDs), sensors, photonic
devices, etc. [1]. Such interest is partly explained by the useful photophysical properties of
donor-acceptor-type organic compounds such as room-temperature phosphorescence (RTP),
thermally activated delayed fluorescence (TADF), or long persistent luminescence (LPL) [2].
Improved efficiency of TADF, RTP and LPL can be achieved for organic luminophores via
molecular and/or film-forming engineering if it leads to improved efficiency of intersystem
crossing and suppressed non-radiative relaxation processes [3]. For example, Adachi et al.
observed efficient LPL for guest-host organic systems [4, 5]. Considering such examples, the
invention of new compounds as well as film-forming approaches may lead to further
improvement in the efficiency of organic luminophores.
In this work, we investigated photophysical properties of four derivatives of triphenylamine and
dibenzothiophene dispersed in different liquids and solid media. Depending on the molecular
structure and media used, the tested compounds exhibited either TADF, RTP or LPL. The
derivatives were utilized as green emitters in OLEDs showing maximum external quantum
efficiency of 13.9% in the best case. One compound with the most efficient RTP and LPL was
selected as the active layer of optical oxygen sensors with a linear sensitivity in the range of
oxygen concentrations of up to 10000 ppm. The Stern–Volmer constant of the best sensor was
4.55×10-4 ppm.
Acknowledgement
This project has received funding from the Research Council of Lithuania (Project “ELOS” No S-MIP-21-30)
and from the Ministry of Education and Science of Ukraine (Project 0122U000760).
References
1. Jing S., Junsen J., Bo Z., Jingjing Y., Manjeet S., Zhongfu A., Hua W., Bingshe X., and Wei H. A purely
organic D-π-A-π-D emitter with thermally activated delayed fluorescence and room temperature
phosphorescence for near-white OLED // Chin. Chem. Lett. – 2021. – Vol. 32, No. 4 – P. 1367–1371.
2. Xiangming W., Mengjiao D., Zijuan L., Zepeng W., and Fu-Shun L. Recent advances of room temperature
phosphorescence and long persistent luminescence by doping system of purely organic molecules // Dyes
Pigm. – 2022. – Vol. 204, – P. 110400.
3. Tiantian W., Man L., Jiayi M., Yimeng L., Lichang W., Dongzhi L., Tianyang W., and Wenping H. Recent
advances in long-persistent luminescence materials based on host–guest architecture // Chin. Chem. Lett. –
2023. –P. 108385.
4. Ryota K., Chihaya A. Organic long persistent luminescence // Nature – 2017. – Vol. 550, – P. 384–387.
5. Parvej A., Tsz S. C., Nelson L. C. L., Jianyu Z., Jing G., Lili D., Ryan T. K. K., Jacky W. Y. L., Zebing Z.,
David L. p., Herman H. Y. S., Ian D. W., and Ben Z. T. Organic long-persistent luminescence from a single-
component aggregate // J. Am. Chem. Soc. – 2022. – Vol. 144, No. 7 – P. 3050–3062.

56
SIMPLICITY AND EFFICIENCY: A HOST-FREE ORGANIC LIGHT-
EMITTING DIODE ATTAINITG 4.6% OF EXTERNAL QUANTUM
EFFICIENCY WITH DERIVATIVE OF 1H-1,2,3-TRIAZOLE AS BLUE
EMISSIVE LAYER
Mariia Stanitska1,2, Nazariy Pokhodylo2, Roman Lytvyn2, Ervinas Urbonas1,
Dmytro Volyniuk1, Khrystyna Ivaniuk3, Pavlo Stakhira3, Rasa Keruckiene1,
Mykola Obushak2, Juozas V. Grazulevicius1
1Department of Polymer Chemistry and Technology, Kaunas University of Technology, Kaunas,
Lithuania
2Department of Organic Chemistry, Ivan Franko National University of Lviv, Lviv, Ukraine
3Department of electronic Engineering, Lviv Polytechnic University, Lviv, Ukraine
The most state-of-art thermally activated delayed fluorescence (TADF)-based organic light-
emitting diodes (OLEDs) are fabricated using complicated multi-layered structures containing
many functional layers typically based on guest-host/co-host systems with a specific
combination of electronic properties of guests and hosts [1,2]. However, efficient TADF-based
OLEDs with few host-free layers are limited due to the limited emitters with a perfect
combination of required electronic properties. Especially in the case of blue OLEDs, device
efficiencies decreased a lot when one or more functional organic layers are skipped from OLED
structures. Our aim was to obtain favourable combination of electronic properties with emission
in the blue spectral region by constructing OLED with a very simple structure
ITO/CuI/TCTA/emitting layer(EML)/TPBi/Ca/Al. We utilised newly synthesized carbazole-
containing derivatives of 1H-1,2,3-triazole as EMLs due to their TADF-originated bluish-green
emission and high PLQYs in solid state. The maximum EQE of 4.6% was achieved for the
device that consisted of 4-(9H-carbazol-9-yl)phenyl)(1-(m-tolyl)-5-(trifluoromethyl)-1H-1,2,3-
triazol-4-yl)methanone as emitting layer. The fabricated OLED exhibited greenish-blue
emission with electroluminescence spectrum characterized by Commission International de
l′Eclairage (CIE) coordinates of (0.34, 0.46). Our research indicates, that by carefully
engineering donor-acceptor type molecules based on 1H-1,2,3-triazole core, it is possible to
fabricate efficient OLEDs even with very simple structure.
References
1. Sarma, M.; Chen, L.M.; Chen, Y.S.; Wong, K.T. Exciplexes in OLEDs: Principles and Promises.
Mater. Sci. Eng. R Reports 2022, 150, 100689.
2. Teng, J.M.; Wang, Y.F.; Chen, C.F. Recent Progress of Narrowband TADF Emitters and Their
Applications in OLEDs. J. Mater. Chem. C 2020, 8, 11340–11353.

57
MECHANOCHROMIC LUMINESCENCE, AGGREGATION-INDUCED
EMISSION ENHANCEMENT AND THERMALLY ACTIVATED
DELAYED FLUORESCENCE OF DERIVATIVES OF PHENOTHIAZINE
AND DIFFERENTLY MODIFIED 3,5-DICYANOPYRIDINE
Lesia Volyniuk1*, Pavel Arsenyan2, Mariia Stanitska1, Oleksandr
Bezvikonnyi1, Algirdas Lazauskas3, Dmytro Volyniuk1, Juozas Vidas
Grazulevicius1
1Department of Polymer Chemistry and Technology, Kaunas University of Technology, K. Barsausko g. 59,
51423, Kaunas, Lithuania; * Corresponding author: lesia.volyniuk@ktu.lt
2Latvian Institute of Organic Synthesis, Aizkraukles 21, LV-1006, Riga
3Institute of Materials Science, Kaunas University of Technology, K. Baršausko St. 59, LT51423 Kaunas,
Lithuania
Mechanochromic (MC) materials represent a type of smart materials that have a wide range of
applications, including mechanosensors, security inks, organic light-emitting diodes, memory
chips, luminescent switches, data storage devices, fluorescent bio-probes [1]. MC responses are
typically caused by physical structural changes [2]. These responses are heavily influenced by
the molecular conformations in the solid state, as well as by the molecular packing modes and
intermolecular interactions. In order to enhance the versatility of MC materials, our goal was to
develop organic materials exhibiting MC luminescence, aggregation induced emission
enhancement (AIEE) and thermally activated delayed fluorescent (TADF).
In this work, we report on MC properties of three newly synthesized derivatives of
phenothiazine and 3,5-dicyanopyridine. We investigated the samples in powder form before and
after they underwent ground, solvent-fumed, heated and melt treatments. The compounds that
were examined had photoluminescence spectra, which showed two bands that peaked at around
420 and 590 nm. These bands corresponded to deep-blue and orange emissions, respectively.
The intensities of deep-blue and orange emissions could be controlled by external stimuli,
resulting in the possibility of achieving even white emission (Fig 1). The TADF and AIEE
properties exhibited by the compounds will be reported.
initial
ground
fumed
heated
melt
Fig 1. Photo of a sample after different external stimuli under UV excitation.
Acknowledgement
This project has received funding from the Research Council of Lithuania (Project “ELOS” No S-MIP-21-7).
References
1. G. Chen and W. Hong. Mechanochromism of structural-colored materials // Adv. Optical Mater. – 2020. –
Vol. 8, P. 2000984.
2. G. Sych, R. Pashazadeh, Y. Danyliv, O. Bezvikonnyi, D. Volyniuk, A. Lazauskas and J.V. Grazulevicius
Reversibly switchable phase‐dependent emission of quinoline and phenothiazine derivatives towards
applications in optical sensing and information multicoding // Chem.Eur.J. – 2021. – Vol. 27, P. 2826 –
2836.

58
CARBAZOLE-BENZOPHENONE DERIVATIVES AS HOSTS FOR
SOLUTION PROCESSABLE GREEN TADF OLED DEVICES
D. Blaževičius1, R. Beresnevičiūtė1, G. Kručaitė1, D. Tavgenienė1, S.
Grigalevičius1, M. R. Nagar2, C. T. Hao2, J.-H. Jou2, K. Kumar3
1Department of Polymer Chemistry and Technology, Kaunas University of Technology, Kaunas, Lithuania
2Department of Materials Science and Engineering, National Tsing Hua University, Taiwan
3School of Chemical Sciences, Indian Institute of Technology, Mandi, HP, India
Solution processable bipolar materials have been reported as emitters and host materials in organic
light emitting diodes (OLEDs) [1]. These materials exhibited a thermally activated delayed
fluorescence nature and have the capability of harvesting triplet excitons from excited triplet to
singlet states by reverse intersystem crossing [2]. Thus, the TADF materials based organic LEDs
have reached an internal quantum efficiency of nearly 100%. Herein, we have successfully designed
and synthesized solution-processable bipolar carbazole-benzophenone derivatives as host materials.
Structures of objective materials are shown in Fig 1.
O
N N
O
N N
N N
BPBCzO BCzBCzO
Fig. 1. Synthesis of objective benzophenone-based materials
These newly synthesized hosts exhibited high-triplet energies, balanced charge-transporting
properties, suitable molecular orbital energy levels, good thermal stability, and good solubility,
which are required to realize green TADF based organic LEDs. Initially, we fabricated two different
types of TADF organic LEDs using these hosts and commercially available guest 4CzIPN as a green
dopant and compared their device characteristics. A green TADF based organic LED employing
BPBCzO host displayed excellent performance with a maximum external quantum efficiency (EQE,
current efficacy (CE), and power efficacy (PE) as high as 23.2 %, 70.7 cd/A, and 55.6 lm/W,
respectively. In particular, over 90% of EQE was reserved (EQE of 21.3%) at the practical
luminance of 1,000 cd/m2, which is advantageous for display technology. At last, green OLED was
also fabricated with a cross-linkable hole transport material 3,6-bis(4-vinylphenyl)-9-ethylcarbazole
and realized PE of 63.6 lm/W with EQE of 25.3%, which could be very effective for lighting and
display devices. These excellent outcomes demonstrate the big potential of the carbazole-
benzophenone derivatives as host materials for next-generation solution-processable display and
lighting technologies.
Aknowledgement
We acknowledge support from the Research Council of Lithuania (grant No. S-MIP-22-84).
References
3. M. Godumala, J. Hwang, H. Kang, J.-E. Jeong, A. K. Harit, M. J. Cho, H. Y. Woo, S. Park, D. H. Choi.
Solution-Processable Pure Green Thermally Activated Delayed Fluorescence Emitter Based on the Multiple
Resonance Effect // ACS Appl. Mater. Interfaces – 2020. – Vol. 12 – P. 35300.
4. N. Ikeda, S. Oda, R. Matsumoto, M. Yoshioka, D. Fukushima, K. Yoshiura, N. Yasuda, T. Hatakeyama.
Solution‐Processable Pure Green Thermally Activated Delayed Fluorescence Emitter Based on the Multiple
Resonance Effect // Adv. Mater. – 2020. – Vol. 32 – P. 2004072.

59
IN THE SEARCH OF NEW METAL-FREE EMITTERS FOR OLEDs
EMPLOYING RPA TECHNOLOGIES
A. Bucinskas1, M. Stanitska1 T. Krilavicius2, J. Šiaulys1, R. Juozaitiene2, B.
Zhyhun2, A. Kristutis1, A. Paulauskaitė-Taraseviciene3, J. V. Grazulevicius1
1Department of Polymer Chemistry and Technology, Kaunas University of Technology, Kaunas, Lithuania
2Faculty of Informatics, Vytautas Magnus University, Kaunas, Lithuania
3Artificial Intelligence Centre, Kaunas University of Technology, Kaunas, Lithuania
Nowadays, organic light-emitting diodes (OLEDs) are widely used in digital displays and are a
promising light-source for future technology[1,2]. Over the last few decades, huge resources
have been devoted to the scientific search for new emitters and development of high-stability
and efficient OLEDs. However, even today this problem remains a big challenge. To develop
high-performance thermally activated delayed fluorescence (TADF) emitters for the 3rd
generation of OLEDs, firstly, a minimal energy gap (ΔEST) between the lowest excited singlet
(S1) and triplet state (T1) is mandatory for reverse intersystem crossing to happen. Another
crucial element is the small spatial overlap between the HOMOs and LUMOs[3,4]. Concerning
these parameters, we developed a semi-autonomous tool generating numerous new metal-free
emitter structures for optoelectronics based on combinatorial screening, RPA (robotic process
automation) technologies and quantum chemistry tools. Additionally, the developed system
offers a significant advantage by operating continuously and autonomously on servers, without
any interruptions, 24 hours a day, 7 days a week. Finally, all generated data and selected
promising new compounds will be stored and presented for researcher overview and future
experimental work. Here in, we will present the principles of our developed tool, which could
significantly improve scientific work in the search of new metal-free TADF emitters.
Acknowledgement
This research was supported by the interinstitutional project (OLEDAI) funded by Kaunas University of
Technology and Vytautas Magnus University. Grant No. (PP2023/39/5).
References
1. Wada, Y. et al. Organic light emitters exhibiting very fast reverse intersystem crossing. Nature Photonics,
2020 14:10, 14(10), P. 643–649.
2. Sudheendran Swayamprabha, S. et al. Approaches for Long Lifetime Organic Light Emitting Diodes.
Advanced Science, 2021, 8(1), P. 2002254.
3. Hussain, A. et al. Theoretical investigations of the realization of sky-blue to blue TADF materials via CH/N
and H/CN substitution at the diphenylsulphone acceptor. Journal of Materials Chemistry C, 2019, 7(22), P.
6685–6691.
4. Han, J. et al. Simple Molecular Design Strategy for Multiresonance Induced TADF Emitter: Highly
Efficient Deep Blue to Blue Electroluminescence with High Color Purity. Advanced Optical Materials,
2022, 10(4), P. 2102092.

60
PEROVSKITE SOLAR CELLS WITH MONOLAYER MODIFIED PTAA
AND ITS APPLICATION TO ALL-PEROVSKITE TANDEM SOLAR
CELLS
D. Tavgenienė1, H. Bi2, Y. Fujiwara2, Ch. Ding2, S. R. Sahamir2, Y. Sanehira2,
A. K. Baranwal2, K. Takeshi2, G. Shi2, G. Kapil2, Z. Zhang2, L. Wang2, T.
Bessho3, H. Segawa3, S. Grigalevicius1, Q. Shen2, S. Hayase2
1Department of Polymer Chemistry and Technology, Kaunas University of Technology, Kaunas, Lithuania.
2i-Powered Energy System Research Center, The University of Electro-Communications, Tokyo, Japan.
3Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, Japan.
Organic-inorganic perovskite solar cells (PSCs) have achieved a recorded power conversion
efficiency (PCE) of 25.7%.[1] Thus, PSCs are considered to be the dominant player in the next-
generation photovoltaic market.[2] So far, single-junction PSCs with narrow bandgap values
have attracted attention.[3] As a member of perovskite materials, wide-bandgap perovskite
(WBG-PVK) can`t be ignored because it is important for tandem solar cells due to its matchable
bandgap.[4] However, low PCE and the current of WBG-PSCs limited the efficiency of the
tandem solar cell. So, it is necessary to further improve the PCE of wide bandgap PSCs.
Here, we demonstrate a series of self-assembled monolayer materials (SAMs) with different
alkyl chain lengths as interfacial modifiers to modify the PTAA and perovskite layer for
improving the optoelectronic properties of PSCs by improving the quality of perovskite films
and increasing the transport and extraction of interfacial carriers (Fig. 1).
Fig 1. New SAMs (named 3,3PrPACz, 4,3BuPACz, and 6,3HePACz)
In conclusion, several new SAMs have successfully been used to modify the interface between
PTAA and WBG perovskite layer. The experimental results show that after the introduction of
4,3BuPACz, the quality of the perovskite thin film has significantly improved.
4,3BuPACz/PTAA-based PSCs achieved a high PCE of 16.57% with a bandgap of 1.77 eV.
The target tandem solar cells gave a PCE of 25.24%, which is the highest PCE of tandem solar
cells based on IZO. This work reveals a buried interface improvement mechanism with
4,3BuPACz/PTAA which can provide valuable guidance for developing effective SAMs buried
layer materials.
Acknowledgement
This work was supported by project S-LJB-22-2 from Research Council of Lithuania.
References
1. Access through internet: https://www.nrel.gov/pv/cell-efficiency.html (NREL, access)
2. Bi H., Guo Y., Guo M., et al. Highly efficient and low hysteresis methylammonium-free perovskite solar cells based on
multifunctional oteracil potassium interface modification // Chem. Eng. J. – 2022. – Vol. 439, – P. 135671.
3. Ma S., Yuan G., Zhang Y., et al. Development of encapsulation strategies towards the commercialization of perovskite
solar cells // Energy Environ. Sci. – 2022. – Vol. 15. – P. 13-55.
4. Xiao K., Lin R., Han Q., et al. All-perovskite tandem solar cells with 24.2% certified efficiency and area over 1 cm2
using surface-anchoring zwitterionic antioxidant // Nat. Energy. 2020. – Vol. 5. – P. 870-880.
N
N
P
OH
O
OH
N
N
PO
HO
HO
N
N
P
OH
O
OH
4,3BuPACz 3,3PrPACz 6,3HePACz

61
NEW MONO-MOLECULAR HTL LAYER FOR WIDE BANDGAP LEAD
PEROVSKITE SOLAR CELLS
Raminta Beresnevičiūtė1, Huan Bi2,3, Jiaqi Liu2, Zheng Zhang2, Liang Wang2,
Daiva Tavgenienė1, Gaurav Kapil2, Chao Ding3, Ajay Kumar Baranwal2,
Shahrir Razey Sahamir2, Yoshitaka Sanehira2, Hiroshi Segawa4, Saulius
Grigalevičius1, Qing Shen2,3, Shuzi Hayase2,3
1Department of Polymer Chemistry and Technology, Kaunas University of Technology, Kaunas, Lithuania.
2i-Powered Energy System Research Center, The University of Electro-Communications, Chofu, Tokyo, Japan.
3Graduate School of Informatics and Engineering, The University of Electro-Communications, Chofu, Tokyo,
Japan.
4Research Center for Advanced Science and Technology, The University of Tokyo, Meguro-ku, Tokyo, Japan.
Recent years have reached intense research and development efforts of perovskite solar cells
(PSCs), due to their growing efficiency [1]. Self-assembled molecules (SAMs) have been
widely employed as hole transport materials (HTL) that can improve the power conversion
efficiency (PCE) of perovskite solar cells (PSCs). In this study, newly carbazole-based material
(4dp3PACz) was synthesized and used as HTL. The structure of compound is shown in Fig. 1.
N
N
4dp3PACz
P
OOH
OH
Fig. 1. Structure of compound 4dp3PACz
The experimental results showed that the mono-molecular layer of 4dp3PACz works as the hole
transport layer better than previously reported 2PACz and PTAA. The perovskite layer
fabricated on 4dp3PACz had better quality, such as less carrier trap densities and longer carrier
lifetime. All-perovskite/perovskite tandem solar cells with 26.47% was reported by coupling the
wide band gap device with 1.77 eV bandgap and narrow band gap device with 1.25 eV bandgap.
Acknowledgement
This work was financially supported by the NEDO project and by project S-LJB-22-2 from Research Council of
Lithuania.
Reference
5. Yan. P., Yang. D., Wang. H., Yang. S., Ge. Z. Recent advantages in dopant-free organic hole-transporting
materials for efficient, stable and low-cost perovskite solar cells // Energy Environ. Sci., 15, 3630-3669
(2022).

62
POLYMERIC ORGANIC LIGHT-EMITTING DIODES BASED ON
EMITTERS EXHIBITING THROUGH-SPACE CHARGE-TRANSFER
TYPE THERMALLY ACTIVATED DELAYED FLUORESCENCE
Dmytro Volyniuk, Melika Ghasemi, Viktorija Andruleviciene, George
Belousov, Irina Vasilenko, Sergei Kostjuk, Juozas Vidas Grazulevicius
Department of Polymer Chemistry and Technology, Kaunas University of Technology, K. Barsausko g. 59,
51423, Kaunas, Lithuania; * Corresponding author: dmytro.volyniuk@ktu.lt
Thermally activated delayed fluorescence (TADF) emitters are among the most promising
electroluminescent materials for organic light-emitting diodes (OLEDs) [1]. They were
developed after the conventional fluorescent and phosphorescent emitters and are considered
the third-generation OLED emitters. Over the past decade, a variety of TADF organic
compounds have been synthesized with deep-blue to red emission. These compounds have been
successfully used for the development of efficient OLED devices. However, the current
fabrication process relies on expensive vacuum deposition techniques. Recently, there has been
a significant interest in TADF polymers as they offer a simple, low-cost, and easily scalable
solution for various methods such as spin-coating and ink-jetting. Through-space charge-
transfer (TSCT) TADF polymers represent one of the most promising emitters for solution-
processable polymeric OLEDs [2]. However, despite their potential, the efficiency of OLEDs
based on TSCT polymers still lags behind the state-of-the-art values.
In this work, we focused on the photophysical and electroluminescent properties of new
polymeric TADF emitters that exhibit TSCT [2]. These emitters have the ability to easily adjust
the colour of their emission from blue to orange. They exhibit exciplex emission via TSCT
mechanism. In addition, delayed fluorescence in the range between 0.35 and 6.2 µs in solid state
was detected which makes the synthesized polymers promising materials for emitting layers of
multicolour solution-processable OLEDs. Although photoluminescence quantum yields of the
solid samples of synthesized alternating copolymers were relatively low (2.12% - 6.32%), the
host-free solution-processable TADF OLED fabricated using one of alternating copolymer with
green emission as emissive material showed promising external quantum efficiency of 7.84%
[2]. The OLEDs exhibited stable electroluminescence spectra at various voltages, indicating
good overall performance. The polymers are promising in terms of light emission, charge
injection, and charge transporting properties and are potentially useful for multi-coloured,
solution-processable electroluminescent devices.
Acknowledgement
This project has received funding from the Research Council of Lithuania (Project “ELOS” No S-MIP-21-30).
References
1. G. Sych, R. Pashazadeh, Y. Danyliv, O. Bezvikonnyi, D. Volyniuk, A. Lazauskas and J.V. Grazulevicius
Reversibly switchable phase‐dependent emission of quinoline and phenothiazine derivatives towards
applications in optical sensing and information multicoding // Chem.Eur.J. – 2021. – Vol. 27, P. 2826 –
2836.
2. G.K. Belousov, A.A. Vaitusionak, I.V. Vasilenko, M. Ghasemi, V. Andruleviciene, A. Ivanchanka, D.
Volyniuk, H. Kim, J.V. Grazulevicius and S.V. Kostjuk. Through-space charge-transfer thermally activated
delayed fluorescence alternating donor–acceptor copolymers for nondoped solution-processable OLEDs //
Macromolecules. – 2023. – Vol. 56(7), P. 2686–2699.

63
BLUE AGGREGATION-INDUCED EMISSION MOLECULES
CONSISTING OF PHENYLSULFONYL-BENZENE CORE AND
TRIPHENYLETHENE-CARBAZOLE MOIETY FOF HIGHLY
EFFICIENT OLEDS
Gintare Krucaite1, Saulius Grigalevicius1, Ming-Jun Lin2, Jian-Sheng Hong
2, Chih-Hao Chang2
1Department of Polymer Chemistry and Technology, Kaunas University of Technology, Lithuania
2Department of Electrical Engineering, Yuan Ze University, Taiwan
Organic light-emitting diodes (OLEDs) are becoming increasingly popular for use in display or
phototherapy lighting applications due to their various advantages such as high-quality color,
low energy cost, light weight, and flexibility [1, 2, 3].
New triphenylethylene compounds EM1, EM2, EM3 were synthesized and are shown in Fig.
1. The photophysical, thermal, and electroluminescence characteristics of the designed emitters
were investigated to clarify the molecular structure-property-performance relationship.
Fig 1. Triphenylethylene compounds.
The OLED device architecture of the doped OLEDs consists of ITO/TAPC/TCTA/mCP doped
with EM1, EM2, or EM3/TmPyPB/LiF/Al. The efficiency decays of formed devices at 102
cd/m2 were respectively estimated to be 17.6%, 0%, and 5.9%, demonstrating the advantage of
EM2. These results indicate that the designed AIE molecules with (phenylsulfonyl)benzene
core (i.e., EM2 and EM3) have high potential for the development of blue-emitting OLEDs.
Acknowledgment
We are thankful to the Research Council of Lithuania (Grant No. S-MIP-22-84) for funding our research.
References
1.
1
. Zhong C., Duan C., Huang F., Wu H., Cao Y. Materials and Devices toward Fully Solution Processable
Organic Light-Emitting Diodes // Chem. Material. -2011- Vol. 23, P. 326–340.
2. Grimsdale A.C., Chan K. L., Martin R. E., Jokisz P. G., Holmes A. B. Synthesis of Light-Emitting
Conjugated Polymers for Applications in Electroluminescent Devices// Chem. Review.-2009-Vol. 109, P.
897-1091.
3. Huang J. H., Xu B., Su J.H., Chen C.H., Tian H., Efficient blue lighting materials based on truxene-cored
anthracene derivatives for electroluminescent devices //Tetrahedron.-2010- Vol. 66, P. 7577–82.
N
O
N
EM 1
N
S OO
EM 2 N
SO
O
EM 3
N

64
RAMAN ANALYSIS OF CuxS THIN FILMS DEPOSITED ON the
SURFACE OF POLYPROPYLENE
Edita Paluckiene1, Martina Gilić2,3, Neringa Petrasauskiene1
1Department of Physical and Inorganic Chemistry, Kaunas University of Technology, Kaunas, Lithuania
2Institute of Experimental Physics, Freie Universität Berlin, Berlin, Germany
3Institute of Physics Belgrade, Belgrade, Serbia
Polypropylene (PP) is one of the most widely used thermoplastic polymers with great chemical,
physical and mechanical properties. In this work, the preparation of electrically conductive
CuxS/PP films by deposition of copper sulfide from an aqueous solution onto a polypropylene
film surface r via chemical bath deposition method (CBD). Copper sulfide layers were deposited
using a mixture of 0.05 M CuCl2 and 0.05 M Na2S2O3 solutions. The CBD process was carried
out from 1 to 3 cycles at room temperature. The duration of each cycle was 16 hours.
In order to find the optimal technological conditions for the CuxS deposition process, the
influence of deposition cycles was studied. Analysis of this material included studies of
structure, morphology and electrical surface conductivity.
Fig. 1. Raman spectra of the CuxS/PP thin films
Raman Spectroscopy is a non-destructive chemical analysis technique which provides detailed
information about chemical structure, phase and polymorphy, crystallinity and molecular
interactions of materials. Raman spectrum of PP 6 (Fig. 1) shows C–C stretching at 808 cm−1
and 972 cm−1, band at 841 cm−1 is related to rocking CH2, rocking at 972 cm−1and 998 cm−1
corresponds to CH3 vibrations [1]. As shown in Fig. 1, the typical Raman spectra copper sulfide
film samples (deposited at 2 and 3 cycles) exhibit similar peak positions. The spectrum reveals
a pronounced peak at 474 cm−1, which is assigned to vibrational (stretching) modes from the
covalent S–S bonds [2] and a much weaker peak at about 270 cm−1 attributed to the Cu–S bond
vibration [2]. Therefore, the main attention was paid to the analysis of the intensity of the most
intense Raman mode at 474 cm−1. Raman analysis confirms the composition of the copper
sulfide on the surface of PP films.
References
1. H. Tadokoro, M. Kobayashi, M. Ukita, K. Yasufuku, S. Murahashi. Normal Vibrations of the Polymer Molecules of Helical
Conformation. V. Isotactic Polypropylene and Its Deuteroderivative // J Chem Phys. – 1965. – Vol. 42, P.1432.
2. Ishii M.; Shibata K.; Nozaki H. Anion Distributions and Phase Transitions in CuS1-xSex(x = 0-1) Studied by Raman Spectroscopy // J.
Solid State Chem. – 1993. – Vol. 105 – P. 504–511.

65
ANALYSIS OF CuxS THIN FILM DEPOSITED ON SURFACE OF
POLYAMIDE – RAMAN SPECTROSCOPY
Neringa Petrasauskiene1, Martina Gilić2, Edita Paluckiene1
1Department of Physical and Inorganic Chemistry, Kaunas University of Technology, Kaunas, Lithuania
2Institute of Experimental Physics, Freie Universität Berlin, Berlin, Germany
3Institute of Physics Belgrade, Belgrade, Serbia
The preparation of electrically conductive CuxS/PA films by deposition of copper sulfide from
an aqueous solution onto a polyamide film surface is reported in this paper.
Copper sulfide (CuxS) layers were deposited on the surface of polyamide via the chemical bath
deposition method (CBD) at room temperature using a mixture of 0.05 M CuCl2 and 0.05 M
Na2S2O3 solutions for 16 h. The CBD process was carried out by varying the number of cycles
(1, 2 or 3 cycles) of deposition. The influence of deposition cycles was studied to determine the
optimum condition for the deposition process. The analysis of this material included studies on
the structure, morphology and electrical surface conductivity.
Fig. 1. Raman spectra of the CuxS/PA thin films
Raman spectroscopy is a useful spectroscopic technique to study the crystal phase, crystallinity
and vibrational properties of the films. Raman spectrum of pure PA 6 (Fig. 1) shows C–C
deformation mode at 630 cm−1, band at 833 cm−1 is related to rocking CH2, while stretching
mode of CH2 is at 935 cm−1, and 962 cm−1 corresponds to CO–NH vibrations [1]. As shown in
Fig. 1, the Raman spectra of copper sulfide film samples (deposited at 2 and 3 cycles) exhibit
similar peak positions. The spectrum reveals a pronounced peak at 474 cm−1, which is assigned
to vibrational (stretching) modes from the covalent S–S bonds [2] and a much weaker peak at
about 270 cm−1 attributed to the Cu–S bond vibration [2]. Therefore, the main attention was paid
to the analysis of the Raman intensity of the most intense mode at 474 cm−1. Raman analysis
confirms the composition of the copper sulfide on the surface of PA films.
References
6. Ferreiro V., Depecker C., Laureyns J., Coulon G. Structures and morphologies of cast and plastically strained polyamide
6 films as evidenced by confocal Raman microspectroscopy and atomic force microscopy // Polymer. – 2004. – Vol.
45, – P. 6013–6026.
7. Ishii M.; Shibata K.; Nozaki H. Anion Distributions and Phase Transitions in CuS1-xSex(x = 0-1) Studied by Raman
Spectroscopy // J. Solid State Chem. – 1993. – Vol. 105 – P. 504–511.

66
DIBLOCK COPOLYMERS OF METHACRYLOYLOXYETHYL
PHOSPHORYLCHOLINE AND DOPAMINE METHACRYLAMIDE:
SYNTHESIS AND SOLUTION PROPERTIES
M. Jurkūnas, A. Šimkutė, R. Makuška
Faculty of Chemistry and Geosciences, Vilnius University, Vilnius, Lithuania
Hydrophilic polymers with phosphorylcholine head groups, such as poly(2-methacryloyloxyethyl
phosphorylcholine) (pMPC), are antifouling materials that are suitable for creating biomimetic cell-
membrane-like structures on various surfaces [1]. This property is valuable for applications
involving biological entities like proteins and cells, biological samples like tears and saliva, and
contact with plasma and blood [2]. Polymers containing MPC segments also serve as effective
lubricants for surfaces in aqueous media.
To incorporate MPC segments onto surfaces, an anchoring polymer block is necessary. Remarkable
adhesive properties are provided by catechol groups, which are present in both mussel adhesive
proteins and recently developed synthetic polymers [3]. Polymers with catechol groups offer a fast
and efficient method for decorating surfaces of different origins with appropriate monolayers.
In this study, bioinspired by excellent adhesion performance of mussels and superior lubrication
performance of phospholipids, biomimetic diblock copolymers of 2-methacryloyloxyethyl
phosphorylcholine (MPC) and dopamine methacrylamide (DOPMA) were synthesized via RAFT
polymerization for the first time. To prevent undesired side reactions during polymerization,
dopamine methacrylamide with acetonide-protected hydroxyl groups (ADOPMA) was used as a
monomer. The diblock copolymers were characterized by SEC with triple detection, NMR
spectroscopy and FTIR spectroscopy.
Amphiphilic diblock copolymers were synthesized starting with the pMPC block. The
polymerization of MPC was well-controlled, resulting in polymers with a very low dispersity index
(Ð about 1.1) and a degree of polymerization (DP) ranging from 20 to 80. Chain extension of pMPC
as a macro-CTA by ADOPMA units produced diblock copolymers with a short pADOPMA block
(DP approximately 10). NMR spectroscopy and DLS data confirmed the formation of amphiphilic
diblock copolymers without residual pMPC. Deprotection of pADOPMA block by TFA was almost
quantitative yielding the desired copolymers pMPC-b-pDOPMA.
The solubility and aggregation behaviour of the diblock copolymers of MPC and DOPMA, both
with protected and unprotected catechol groups, were studied by DLS. The diblock copolymers with
protected catechol groups exhibited full solubility in methanol but formed micelles with a
pADOPMA core and a pMPC shell in aqueous solution. None of the solvents, including methanol,
dissolved the diblock copolymers with unprotected catechol groups. Evidently, the catechol
hydroxyl groups formed hydrogen bonds with each other, creating a tightly packed core structure
regardless of the solvent. Surprisingly, raising the solution temperature to 45 C resulted in the
dissolution of the diblock copolymers in water, demonstrating the thermoresponsive nature of such
copolymers.
References
1. Goda T., Ishihara K., Miyahara Y. Critical update on 2-methacryloyloxyethyl phosphorylcholine (MPC)
polymer science // J. Appl. Polym. Sci. – 2015. – Vol. 132, No. 16 – P. 41766.
2. Chen S.-H., Chang Y., Ishihara K. Reduced blood cell adhesion on polypropylene substrates through a
simple surface zwitterionization // Langmuir. – 2017. – Vol. 33, No. 2 – P. 611–621.
3. Guo Q., Chen J., Wang J., Zeng H., Yu J. Recent progress in synthesis and application of mussel-inspired
adhesives // Nanoscale. – 2020. – Vol. 12, No. 3 – P. 1307–1324.

67
BIOBASED POLYESTER COMPOSITES FOR PACKAGING
APPLICATIONS
Juris Bitenieks, Remo Merijs-Meri, Janis Zicans, Tatjana Ivanova, Rita
Bērziņa
Institute of Polymer Materials, Riga Technical University, Riga, Latvia
The increasing concerns of food packaging waste on the environment are raising interest on
more sustainable polymer materials and their composites to reduce environmental impact. In
this case bio-based polymers are considered as a less harmful alternative to traditional plastics
[1]. To enhance the properties of bio-based polymer composites, additional natural fillers were
chosen. The nanoclay filler was used as to improve the polymer matrix mechanical and thermal
properties [2]. Additionally, to improve antibacterial properties chitosan with different degree
of acetylation was used [3].
Bio-based polyester from NaturePlast with either 35% (PBE 001) or 50% (PBE 003) of bio-
based polymer content was used as a matrix for packaging films. The bio-based polymer
composite samples with nanoclay (Nanocor) at 1 – 5 wt.% and chitosan (C95 and C98) at 3 –
10 wt.% were prepared by laboratory two-roll mills. Samples for rheology, dynamic mechanical
analysis and tear resistance tests were obtained by compression molding.
Results showed that C95 and C98 chitosan fillers from 3 to 10 wt. % increase melt viscosity of
the bio-polymer matrix whereas the nanoclay effect on the viscosity increase was to a lesser
extent. In contrast dynamic mechanical analysis showed that nanoclay filler at higher
concentrations improved bio-based polymer composite storage modulus indicating on
reinforcing effect while chitosan effect on this parameter was minimal. Similar reinforcing
effect of the nanoclay was observed in tear test of the bio-based polymer films.
Acknowledgement
This research is funded by the Latvian Council of Science, project “Smart Materials, Photonics, Technologies and
Engineering Ecosystem” project No VPP-EM-FOTONIKA-2022/1-0001
References
1. Babu R. P., O’Connor K. and Seeram R. Current progress on bio-based polymers and their future trends //
Prog Biomater. – 2013. – Vol. 2, No. 8.
2. Taleb K., Saidi-Besbes S., Pillin I. and Grohens Y. Biodegradable Poly(Butylene Succinate)
Nanocomposites Based on Dimeric Surfactant Organomodified Clays with Enhanced Water Vapor Barrier
and Mechanical Properties // ACS Omega – 2022. – Vol. 7 – P. 43254−43264.
3. Oladzadabbasabadi N., Nafchi A. M., Ariffin F., Wijekoon M. M. J. O., Al-Hasan A. A., Dheyab M. A. and
Ghasemlou M. Recent advances in extraction, modification, and application of chitosan in
packaging industry // Carbohydr. Polym. – 2022. – Vol. 277 – 118876.

68
PVA THERMOELECTRIC NANOCOMPOSITE CONTAINING
MWCNT-Sb2Te3 AND MWCNT-Bi2Se3 HYBRID FILLERS
Juris Bitenieks1, Remo Merijs-Meri1, Janis Zicans1, Tatjana Ivanova1, Jana
Andzane2, Krisjanis Buks2, Donats Erts2
1Institute of Polymer Materials, Riga Technical University, Riga, Latvia
2Institute of Chemical Physics, University of Latvia, Riga, Latvia
Thermoelectric materials are known for their ability to convert heat energy in to electrical
energy. This can be achieved due to their characteristic low thermal conductivity and high
electrical conductivity. Usually these materials are various inorganic compounds consisting of
Bi, Te and other metallic elements. However, in recent years polymer based thermoelectric
composites have received attention because of many benefits that they can provide to
thermoelectric materials like lower density, cost reduction and mechanical flexibility [1].
In this work thermoelectric Sb2Te3 and Bi2Se3 fillers were synthesized on multi-walled carbon
nanotube (MWCNT) surface by physical vapor deposition method [2]. Then obtained hybrid
fillers were mixed into aqueous polyvinyl alcohol (PVA) dispersion to obtain PVA/MWCNT-
Sb2Te3 and PVA/MWCNT-Bi2Se3 thermoelectric polymer composites. Flexible free-standing
films of thermoelectric polymer composites for the characterization were obtained by solution
casting.
Results showed that PVA/MWCNT-Sb2Te3 and PVA/MWCNT-Bi2Se3 films presented
significant Seebeck coefficient, electrical resistivity and power factor parameters at hybrid filler
concentrations at 15 wt.%. Seebeck coefficient measurements indicated that MWCNT-Sb2Te3
possess p-type and MWCNT-Bi2Se3 possess n-type thermoelectric behaviour. Besides
thermoelectrical properties, hybrid fillers showed improvement in storage modulus of PVA
matrix above glass transition temperature indicating on additional reinforcement effect. Lower
LCTE values of the both hybrid fillers containing composites indicated on formation of the filler
network throughout the PVA matrix and thus improving the dimensional stability of the
composite by restricting the PVA macromolecular movement [3, 4].
References
1. Wang L., Liu Y., Zhang Z., Wang B., Qiu J., Hui D. and Wang S. Polymer composites-based thermoelectric
materials and devices // Compos. B: Eng. – 2017. – Vol. 122 – P. 145–155.
2. Buks K., Andzane J., Smits K., Zicans J., Bitenieks J., Zarins A., Erts D. Growth mechanisms and related
thermoelectric properties of innovative hybrid networks fabricated by direct deposition of Bi2Se3 and Sb2Te3
on multiwalled carbon nanotubes // Mater. Today Energy – 2020. – Vol. 18 – 100526.
3. Bitenieks J., Buks K., Merijs-Meri R., Andzane J., Ivanova T., Bugovecka L., Voikiva V., Zicans J. and Erts
D. Flexible N-Type Thermoelectric Composites Based on Non-Conductive Polymer with Innovative
Bi2Se3-CNT Hybrid Nanostructured Filler // Polymers – 2021. – Vol. 13 – 4264,
4. Andzane J., Buks K., Bitenieks J., Bugovecks L., Kons A., Merijs-Meri R., Svirksts J., Zicans J. and Erts D.
p-Type PVA/MWCNT-Sb2Te3 Composites for Application in Different Types of Flexible Thermoelectric
Generators in Combination with n-Type PVA/MWCNT-Bi2Se3 Composites // Polymers – 2022. – Vol. 14
– 5130.

69
PRE-LOVED BIOTEXILE SUBTITLE DESIGNING WITH
UNRECYCLABLE TEXTILE FIBRES
S. Polakova1,2, M. Bērziņa1, R. Merijs-Meri2, A. Bernava2, R. Bērziņa2, J.
Bitenieks2
1Studio Sarmite, 1-5 Schwedlerstraße, Frankfurt am Main, HE, 60314, Germany
2Institute of Polymer Materials, Faculty of Materials Sciences and Applied Chemistry, Riga Technical University,
3 Paula Valdena street, Riga, LV-1048, Latvia
Over the last two years designers Sarmite Polakova and Mara Berzina have researched colour
separated post-consumer fibres. In a collaborative project with Riga Technical University, the
designers dived into the depths of a single colour – yellow - and translating it into a marble-like
colour palette. Waste does not have a single tone. Instead it mesmerizes with depths and patterns
that create a complexity visible once looked closer at. Pre-Loved creates an alternative to the
flawed traditional textile recycling. A unique production method turns inferior mixed blends into
a sturdy bio-textile suitable for fashion, interior and product design applications. The
lightweight leather-like material reveals new aesthetics and highlights the previous lives of each
worn garment through colour and structural nuances. Pre-Loved is part of a larger project
investigating various waste streams from the textile industry. Post-consumer garments,
production waste, fibres, dust and even dye waste are seen as a resource for the creation of new
material concepts.
About Studio Sarmite: Studio Sarmite is a materials design and research studio founded in
Amsterdam, Netherlands and currently based in Frankfurt, Germany. Led by Latvian designer
Sarmite Polakova, the studio work focuses on transforming industry waste and various by-
products into new closed-loop concepts that can be brought back to the market. The studio’s
design practice consists of hands-on experimental research with the manipulation of existing
designing and production methods. This playful, sometimes even silly approach leads to
surprising findings that also question our existing ways of producing, consuming and discarding.
Acknowledgment
This work was supported by COSME Programme of the European Union for the Competitiveness of
Enterprises and Small and Medium-Sized Enterprises (SMEs) in the framework of the “WORTH
Partnership Project II” Partnership between Studio Sarmite and Riga Technical University
Credits:
Studio Sarmite A design studio for non-heroic materials.
Designers Sarmite Polakova and Mara Berzina
Collaboration with Riga Technical University (RTU)
Website: https://studiosarmite.com
Instagram: @studio_sarmite

70
XRD and SEM/EDS STUDIES OF COBALT SULFIDE LAYERS ON
POLYAMIDE 6
Klaudija Vaičiukynaitė1, Remigijus Ivanauskas1, Skirma Žalenkienė1
1Department of Physical and Inorganic Chemistry of Kaunas University of Technology, Lithuania
For several decades, new composite materials with various combinations of physical and
chemical properties have been rapidly gaining importance in various fields of modern
technology. Polymers with thin sulfide layers classified as composites. Composite materials, in
addition to the useful properties of the polymer, such as plasticity, resistance to external
influences, and low cost, acquire a number of valuable properties of the inorganic layer.
Transition metal chalcogenides such as CoSe, CoTe, and CoS have attracted worldwide interest
due to their layer-resistant physical and chemical properties and are considered among the most
promising electrode materials. It is known that the stoichiometric composition of cobalt sulfide
[1], as well as different morphology and surface structure, have a great influence on the electrode
characteristics of materials [2].
Therefore, it is very important to be able to control the quantitative and qualitative composition
of the resulting layers.
In this work, layers of cobalt sulfide with different compositions of cobalt and sulfur were
deposited on a polyamide substrate by a technologically simple and inexpensive two-stage
adsorption-diffusion method. Strips of polyamide 1.57 cm in size, 500 mm thick and with a
density of 1.13 g/cm3 were used as the substrate. Higher polythionic acids (H2SnO6) with n > 6,
compounds containing chains of divalent sulfur atoms, were used as a sulfurization agent.
Cobalt(II) sulfate ammonia complex solution was used as a source of cobalt. To sulfurization,
the polymer, the strips were immersed in solutions of polythionic acids with a concentration of
0.01 mol/L for various durations at a temperature of 60 ºC. At the second stage, the samples
were treated with a cobalt precursor solution for 20 min at various temperatures. The influence
of the deposition conditions on the structural properties, morphological and chemical
composition of the deposited layers of cobalt sulfide was studied by X-ray phase analysis
(XRD), scanning electron microscope (SEM) and energy-dispersive spectroscopy (EDS). The
results of X-ray diffraction and chemical analysis confirmed the formation of layers of cobalt
sulfide particles on the surface of polyamide strips. It was also found that with an increase in
the concentration of cobalt sulfide in the layer formed on the polymer, the structural order of
these layers increases towards a uniform one.
References
1. Jamal, F.; Rafique, A.; Moeen, S.; Haider, J.; Nabgan, W.; Haider, A.; Imran, M.; Nazir, G.; Alhassan, M.;
Ikram, M.; et al. Review of Metal Sulfide Nanostructures and Their Applications // CS Appl. Nano Mater. –
2023. – Vol. 6, No. 9 – P. 7077–7106.
2. Jamal, F.; Rafique, A.; Moeen, S.; Haider, J.; Nabgan, W.; Haider, A.; Imran, M.; Nazir, G.; Alhassan,
M.; Ikram, M.; et al. Review of Metal Sulfide Nanostructures and Their Applications // CS Appl. Nano
Mater. – 2023. – Vol. 6, No. 9 – P. 7077–7106.

71
SCRATCH RESISTANCE OF HOT STAMPED MULTILAYER
STRUCTURES VS ADHESIVE NATURE AND THICKNESS
Singhal Shubaum1, Viktoras Grigaliūnas2, Pranas Narmontas2, Jolanta
Donelienė3, Juras Ulbikas3,4, Eglė Fataraitė-Urboniene1,3
1Department of Production Engineering, Faculty of Mechanical Engineering and Design, Kaunas University of
Technology, Kaunas, Lithuania
2 Institute of Materials Science, Kaunas University of Technology, Kaunas, Lithuania
3Applied Research Institute for Prospective Technologies, Vilnius, Lithuania
4JSC “Modernios E-Technologijos”, Vilnius, Lithuania
The quality of document security devices with embossed hologram in the multilayer polymer
based film depends not only on the hologram embossing technology and security level, but also
on the hot stamping quality, which can vary in dependence of hot stamping regimes and adhesive
layer properties.
The aim of this investigation was to find out the influence of the nature and thickness on the hot
stamping.
Three water-based adhesives (S35.3197 (A1) and S35.3213 (A3) (Nolax, Switzerland), OPU746
(A2) (Lotto, Germany)) and one solvent-based adhesive TC-03 (A4) (Centro Grafico DG SpA,
Italy) adhesive with different concentrations and viscosity were selected for the research. Rods
with dfferent wire diameter (d = 4, 14, 24, 50 and 80 µm) were used to apply the adhesive layer
on the multilayer metallized polymer film with embossed hologram. The thickness of the formed
adhesive layer was measured using the Coating Thickness tester, CEM DT-156 (as a result, an
average of 6 measurements was selected). The hot stamping procedure was performed on the
paper substrate (grammage of 80g/m2) using different press head temperature (60º, 73º, 90º,
106º and 113ºC), press load of 18N and pressing duration =1s. Scrach tests at constant load of
261 mN, 290 mN, 310 mN, 330 mN and 359 mN was carried out in order to evaluate quality of
coating as well as quality after hot stamping on the paper substarte. Adhesive layer structure,
scrach groove width and shape was evaluated visualy by optical microscopy.
It was obtained that between rod wire diameter and adhesive layer thickness a linear dependence
exists. The structure and quality of the adhesive layer formed on the multilayer film surface is
highly dependent on the adhesive nature, its viscosity, and adhesive layer thickness. The scratch
resistance of the adhesive layer depends on the structural parameters of the adhesive layer and
scraching conditions. At small scrach loads a groove was not formed, and at higher scrach loads
the shape and width depends on adhesive layer. The same tendency was carried out for hot
stamped structures. The best quality of stamped structures was found in case of adhesive layer
A1 (rod diameter d=14µm, hot stamping temperature T=106ºC; rod diameter d=24µm, hot
stamping temperature T=73º, 90º, and 106ºC; rod diameter d=50µm, hot stamping temperature
T=73º, 90ºC) adhesive layer A2 (rod diameter d=14µm, hot stamping temperature T=106ºC;
rod diameter d=24µm, hot stamping temperature T=106ºC; rod diameter d=50µm, and hot
stamping temperature T=90º, 106º C) and for adhesive A4 at rod diameter d=50µm and hot
stamping temperature T=106º C. These structures were selected for final evaluation. It was
found that at smaller loads (P = 261 and 290 mN) independent of the structural parameters of
the adhesive layer, the groove was not formed, while in the case of higher scrach loads (P =
309.89, 329.5 and 358.92 mN), adhesive failure from the paper substrate or cohesive failure of
the multilayer structure was observed.

72
ELECTROSPUN MATERIALS IN TRIBOELECTRIC SERIES
Natalja Savest1, Illia Krasnou1, Andres Krumme1, Illia Dobryden2, Karl
Håkansson2, Jesper Edberg3,
1Laboratory of Biopolymer Technology, Tallinn University of Technology, Tallinn, Estonia
2 Bioeconomy and Health, RISE Research Institutes of Sweden, Drottning Kristinas väg 61, Stockholm, SE-114
28 Sweden
3 Printed-, Bio- and Organic Electronics, RISE Research Institutes of Sweden, Bredgatan 35, Norrköping, SE-602
21 Sweden
Electrospun nanofibrous materials are known to be suitable for applications in many areas from
fabric technology, healthcare to energy devices. The interest to these materials is increasing.
Due to the nanostructured morphology, fibrous materials in nano size demonstrate the better
properties comparing to bulk materials. Larger specific surface area, good uniformity, large
porosity, and tiny size are the advantages of electrospun materials that can provide a new choice
for the triboelectric series.
Electrospinning is known as an effective fibre processing method. Electrospinning technique
allows to choose various polymers using more and more biodegradable ones and produce
electrospun materials with different structural characteristics and improved properties. It is also
believed that applying electrospinning the triboelectric effect of the polymer materials will be
enhanced because of the fibrous structure.
The aim of this research is to produce cellulose based materials by electrospinning method for
energy harvesting applications. Cellulose acetate, Nylon and carbon black as a conductive
additive have been chosen to prepare positive, negative, and conductive mats and to be tested in
triboelectric series. To achieve the conductivity of the electrospun mat carbon black
concentration was investigated from 3 wt% up to 30 wt%. The properties of the produced
electrospun materials were characterized with tensile testing to estimate mechanical durability
of the material, SEM analysis to characterize morphology and the conductivity was measured
by 4-probe and 8-probe methods. Voltage characterizations and charge density measurements
have been performed showing stability in triboelectric series and promising results for energy
harvesting.
Acknowledgement
This research is the joint project between RISE and Taltech funded by Södra Skogsägarnas Stiftelse för Forskning,
Utveckling och Utbildning.
Reference
1. Reddy V.S., Tian Y., Zhang C., Roy Ye. K., Chinnappan, Ramakrishna S., Liu W., Ghosh R. A review on
electrospun nanofibers based advanced applications: from health care to energy devices / / Polymers – 2021.
– Vol. 13, No. 21:3746 – P. 1-39.

73
FEATURES OF THE PROCESSING THE POLYMER MIXTURE WASTE
BASED ON GLASS-FILLED POLYAMIDE
S. V. Prystynskyi1,2, V. P. Plavan1
1Department of Chemical Technologies and Resource Saving, Kyiv National University of Technologies and Design,
Ukraine
2LLC Kostal Ukraine, Pereyaslav, Kyiv Region, Ukraine
The main difficulty in processing a mixture of polymers by injection molding or extrusion is the
compatibility of materials, which requires the addition of compatibilizers1). Considering the fact that the
content of polymer materials in the mixture can be different by mass, there is a need for a more detailed
study of the properties and behavior of the obtained composition, because changes in the properties of the
material can occur due to the influence of the chemical structure of polymers and fillers2,3). The purpose of
this research is to study the rheological properties and morphology of the mixture obtained from
multicomponent polymer waste from glass-filled polyamide 6 (РА6GF30) and polycarbonate (PC) in
various ratios for further forecasting and understanding of the production process parameters.
During the experiment, defective parts and technological waste from РА6GF30 and PC were crushed on a
Rapid 200 crusher. The resulting mixture of PA6GF30/PC (90/10% by mass) was divided into separate
components by sorting the elements of the parts. The melt flow rate (MVR and MFR) was measured on an
MFI-1322 device with data processing according to ISO 1133. The morphology of mixtures of
multicomponent waste with PA6GF30/PC in different ratios was evaluated by microphotographs of the
extrudate section after the melt flow rate was determined using microscopic equipment Mitutoyo QS250Z.
During the research, a decrease in melt flow rate (MVR, cm3/10 min) was observed by 19% on average
with each step of adding 10% by weight of PC to PA6GF30 until reaching a distribution of PA6GF30/PC
of 60/40% by mass. According to the distribution of PA6GF30/PC 40/60% by mass, an increase in MVR
by 47% was established, which is the maximum value of the melt flow rate. This indicates the achievement
of the eutectic effect, in which the components of the melt simultaneously crystallize at the appropriate
temperature. It is likely that in this case the mixture has a temperature of simultaneous crystallization of the
substances, which is lower than the individual polymer composition and the obtained secondary polymer
mixture has properties that are not inherent to any component. When increasing the concentration of PC
up to 80% by mass again, an increase in fluidity was observed. This indicates the superiority of the
properties of PC over PA6GF30. According to the results of microscopic studies, it was established that
PC is mainly distributed in the shell of PA6GF30. A wider distribution of PC in the PA6GF30/PC mixture
(60/40% by weight) is also visualized. This in turn confirms the fact that the secondary polymer mixture
acquires mainly the properties of PC.
The obtained results confirm the possibility of processing multicomponent waste polymer composite
materials by injection molding without their separation in the absence of significant influence on the
process parameters. The composition and properties of the RA6GF30/RS eutectic mixture, which has a
higher melt flow rate than that of the individual materials, allows reducing the processing temperature and
injection pressure. This simplifies the process of re-processing of unsorted multi-component waste as
opposed to the processing of separate polymer compositions, which makes it possible to reduce the
negative impact on the environment.
References
1. Okan, Meltem; Aydin, Halil Murat; Barsbay, Murat. Current approaches to waste polymer utilization and minimization: A review. Journal of Chemical
Technology & Biotechnology. – 2019. – Vol. 94, No.1. – p. 8-21.
2. He, C., Lin, Y., Xiao, C., Lang, F., & Li, D. Preparation and characterization of BN modified PA6/PC thermal conductive composites. Soft Materials. –
2022. – Vol. 20, No. 3, – p. 278-287.
3. Reinaldo, J. S. at all. Thermal, mechanical and morphological properties of multicomponent blends based on acrylic and styrenic polymers. Polymer
Testing. – 2020. – Vol. 82. – p. 106265.

74
POLYAMIDES MODIFIED BY COMPOUNDS WITH SILOXANE
GROUPS
Volodymyr Sytar1, Оleh Kabat1, Agnese Ābele2, Ritvars Bērziņš2
1Ukrainian State University of Chemical Technology, Dnipro-City, Ukraine
2Institute of Polymer Materials, Riga Technical University, Riga, Latvia
The intensive development of various branches of technology requires the development of
structural materials with a high level of strength properties in a wide temperature range. It is
especially actual for the friction and sealing units of the machine and mechanisms. Based on
this, aromatic polyamides were chosen as the polymer base to solve the tasks, the units from
which are characterized by a high level of operational properties [1,2].
To improve the tribological properties, finely dispersed graphite was added to their composition,
which had the effect of increasing wear resistance and reducing the coefficient of friction during
frictional interaction with steel [3]. However, a decrease in the mechanical properties of the
obtained polymer composites (PCs) is observed.
In order to improve the mechanical properties, studies were conducted on the modification of
graphite-filled PCs with siloxane modifiers. This is due to the fact that internal stresses arise at
the polymer-filler phase interface as a result of the inhibition of relaxation processes and the
difference in the coefficients of thermal expansion of the polymer and the filler, the reduction
of which can be achieved by modifying the surface of the filler with a damping layer.
It is this role that siloxane modifiers perform. When studying the properties of multicomponent
systems based on aromatic polyamides, the most important thing is to establish a functional
relationship between the values of strength and tribological properties and the factors that
determine them.
It has been established that the introduction of siloxanes into PCs based on aromatic polyamides
leads to improve their properties. This is due to a change in the energy of intermolecular
interaction and the structure of the polymer, which opens up opportunities for its use in friction
and sealing units. The obtained PCs are able to increase the service life and improve the tightness
of the equipment, thereby solving the environmental problem of protecting the environment
from toxic emissions.
The developed materials passed industrial tests as a seal for high-pressure compressors instead
of babbit, which made it possible to increase their durability by 3-5 times. The use of developed
materials for sealing pumps by Peroni Pompe (Italy) significantly increased the durability of
this equipment.
Thus, the modification of aromatic polyamides with siloxanes significantly increases the
operational properties of parts from these materials and has a wide perspective for their usage
in friction and sealing units.
References
1. Sytar V., Kuzyayev I., Kabat O., Kudrayvtsev A. Heat-resistant gas-filled composites based on phenylon and inorganic pore formers //
Jour. Chem. Tech. – 2023. – Vol. 31. No 1, – P. 120–127.
2. Kabat O., Makarenko D., Derkach O, Muranov Y. Determining the influence of the filler on the properties of structural thermal-resistant
polymeric materials based on phenylone C1 // East-Eur. Jour. Enter. Tech. – 2021. – Vol. 5. No 6(113). – Р. 24–29.
3. Sytar V.I., Kuzyaev I.M., Burya A.I., Kholodilov O.V., Kabat O.S. Optimization of the triboengineering characteristics of a phenylon-
based composition // Trenie i Iznos/ 2004. Vol. 25. No 2, P. 219–222.

75
DEVELOPMENT OF BIOBINDERS WITH IMPROVED
PERFORMANCE AND ANTIOXIDANT PROPERTIES BY PARTIAL
SUBSTITUTION OF BITUMEN WITH LIGNIN
V.Haritonovs1, R. Merijs-Meri2, J. Zicans2, V. Straupe1, V. Zabolotnii3, M.
Tamosiunas3, R. Viter3, A. Arnautovs4
1Department of Roads and Bridges, Riga Technical University, Kipsalas street 6a, Riga, LV-1048, Latvia
2Department of Polymer Materials Technology, Riga Technical University, Paula Valdena street 3, Riga, LV-1048,
Latvia
3Institute of Atomic Physics and Spectroscopy, University of Latvia, Jelgavas street 3, Riga, LV-1004, Latvia
4Institute of Mechanics of Materials, University of Latvia, Aizkraukles street 23, Riga, LV-1006, Latvia
Most binders that are used for pavement materials are derived primarily from fossil fuels. Bio-binder
is an asphalt binder alternative made from non-petroleum-based renewable resources, which should
not rival any food material, and have environmental and economic benefits. The development of
bio-based materials is consistent with the principles of Green Chemistry and Engineering, which
pertain to the design, commercialization, and use of processes and products that are technically and
economically feasible while minimizing the generation of pollution at the source and the risk to
human health and the environment.
Lignin is the second most abundant natural polymer surpassed only by cellulose; millions of tons of
lignin are produced from the pulp and paper industry annually, however very little amount of it has
been transformed into value-added bioproducts. More than 50 million tons of lignin is generated
from the pulp and paper industry annually, but only 2% of this waste has been utilized. Lignin is
natural polymer that reflects the structure of bitumen and therefore it could be used as suitable
modifier for bitumen.
The aim of the research is innovative use of lignin-based modifier FKL (fractionated Kraft lignin)
for development of "bio-binders" with enhanced performance at high and low temperatures as well
as antioxidant properties. Optimal percentages of crude oil bitumen and FKL as well as
technological parameters for manufacturing of bituminous binder compositions were determined
based on rheological, physical and mechanical characteristics. Substitution of bitumen with FKL
has been carried out up to 60%
Production of bitumen-FKL compositions was carried out with a high shear mixer at 160ºC, with
5000-6000rpm and mixing time from 10 to 60 minutes.
The obtained results show that because of partial substitution of the bitumen B70/100 with FKL, rut
resistance is improved, as the softening point and critical temperature, determined by DSR test,
increase from 48ºC to 65ºC and from 65ºC to 76ºC respectively. A rapid increase in dynamic
viscosity at 135ºC temperature is observed when replacing 50% of bitumen with FKL, which means
high viscosity during asphalt concrete production and the need for viscosity-reducing warm mix
asphalt (WMA) additive. A rapid increase in dynamic viscosity from 111 mPa·s to 3456 mPa·s when
substituting bitumen with 60% FKL may mean a phase change, i.e. FKL becomes the continuous
phase of the bitumen-FKL system. Determination of antioxidant properties of traditional bitumen
B70/100 and modified B70/100-FKL has been performed by using FTIR, Raman and optical
spectroscopy. Analysis of the structure and chemical properties of B70/100 and B70/100-FKL
modified was performed. Effect of FKL modification to improvement in aging properties of
B70/100 samples is discussed.
Acknowledgement
This research is funded by the Latvian Council of Science, project “Smart Materials, Photonics,
Technologies and Engineering Ecosystem” project No VPP-EM-FOTONIKA-2022/1-0001