Figure - available from: Journal of Polymers and the Environment
This content is subject to copyright. Terms and conditions apply.
DSC curves of films before and after AAT. a PBAT/PHA, cooling scan, b PBAT/PHA, second heating scan, c PBAT/PHA-UVA, cooling scan, d PBAT/PHA-UVA, second heating scan
Source publication
The degradation and stability of biodegradable films determine the service length of mulch films in actual use. Most biodegradable polymers degrade too fast to meet the required durability of mulch films. The objective of this work is to investigate the degradation behaviors of poly(butylene adipate-co-terephthalate) (PBAT)/polyhydroxyalkanoate (PH...
Citations
... They have a racted a ention because of their similarity to conventional plastics, their biocompatibility, biodegradability, and non-toxicity, among other characteristics [5]. In this context, PHAs have gained a prominent position due to their biodegradability in different scenarios, i.e. compost, soil or aquatic media [6]. Moreover, their physical properties can be modified by changing their monomeric components, which broadens their field of application. ...
In the present study, a multilayer high barrier thin blown film based on a polybutylene adipate terephthalate (PBAT) blend with polyhydroxyalkanoate (PHA), and composed of four layers, including a cellulose nanocrystals (CNC) barrier layer and an electrospun poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) hot-tack layer, was characterized in terms of surface roughness, surface tension, migration, mechanical and peel performance, barrier properties and disintegration rate. The results showed a material with a smooth surface. The overall migration test showed that the material was suitable for its use as a food contact layer. The addition of the CNC interlayer had a significant effect on the mechanical properties of the system, drastically reducing the elongation at break and, thus, the flexibility of the material. However, the material retained its elastic modulus and tensile strength. The CNC coating had a negative impact on the peeling strength, weakening the inherently strong interlayer adhesivity of the electrospun PHBV fibers. The multilayer had a good barrier to water vapor, and especially to oxygen, with its permeance reduced by up to a 90 % when the CNC layer was present. Finally, the monolayer blend film disintegrated in a period of less than 55 days in a laboratory-scale composting experiment, while the multilayer system disintegrated in 60 days. Overall, the multilayer system formed a fully compostable structure with great potential for use in food packaging applications.
... Higher fiber disintegration was observed in the PLA/PBAT/CO fiber after 3 months of decomposition. As the degradation progressed, a loss of transparency of the fibers was observed due to possible loss of crystallinity associated with PLA component hydrolysis and sample biodeterioration, as reported by Brdlík et al. [30] and Carbonell-Verdu et al. [15]. PLA/PBAT/PPF/CO/AA fibers with and without temperature showed similar degradation behavior. ...
... For the other blends, the cold crystallization temperature (Tcc) was lower compared to PLA and, as degradation time increased, the Tcc increased. Values between 117 °C and 120 °C have been reported in the literature [15,30]. Nomadolo et al. [41] and Vasile et al. [38] found higher values of Tcc for PLA compared to the blends, as shown in this work. ...
... The cold crystallization peak for the PLA (Figure 6a) was at around 115 • C and for the PLA/PBAT blend (Figure 6c) at around 113 • C. For the other blends, the cold crystallization temperature (T cc ) was lower compared to PLA and, as degradation time increased, the T cc increased. Values between 117 • C and 120 • C have been reported in the literature [15,30]. Nomadolo et al. [41] and Vasile et al. [38] found higher values of T cc for PLA compared to the blends, as shown in this work. ...
Nowadays, solving the problems associated with environmental pollution is of special interest. Therefore, in this work, the morphology and thermal and mechanical properties of extruded fibers based on polylactic acid (PLA) and poly(butylene adipate-co-terephthalate) (PBAT) added to prickly pear flour (PPF) under composting for 3 and 6 months were evaluated. The highest weight loss percentage (92 ± 7%) was obtained after 6-month degradation of the PLA/PBAT/PPF/CO/AA blend, in which PPF, canola oil (CO), and adipic acid (AA) were added. Optical and scanning electron microscopy (SEM) revealed structural changes in the fibers as composting time increased. The main changes in the absorption bands observed by Fourier transform infrared spectroscopy (FTIR) were related to the decrease in -C=O (1740 cm−1) and -C-O (1100 cm−1) groups and at 1269 cm−1, associated with hemicellulose in the blends with PPF. Differential scanning calorimetry (DSC) showed an increase in the cold crystallization and melting point with degradation time, being more evident in the fibers with PPF, as well as a decrease in the mechanical properties, especially Young’s modulus. The obtained results suggest that PPF residues could promote the biodegradability of PLA/PBAT-based fiber composites.
... The main research is based on degradable resins such as poly (butyleneadipate-co-terephthalate) (PBAT) [8], polylactic acid (PLA) [9], polypropylene carbonate (PPC) [10], and polyhydroxyalkanoates (PHAs) [11]. Using them as raw materials for biodegradable mulch films Meanwhile, the degradation properties and degradation process of plastic films have been extensively studied [12][13][14][15][16][17]. However, uncontrolled degradation cycles occur in most degradable polymer coverings, and the high price of their ...
The preparation of biodegradable mulch film to replace non-degradable mulch film is of great significance for reducing the harm of non-degradable agricultural mulch film to the environment. However, there are few studies on the degradation performance and degradation mechanisms of degradable cellulose mulch. Therefore, the wet papermaking process was adopted in this work. Salix fiber and wheat straw fiber were used as raw materials. A Salix/wheat straw fiber degradable film was prepared by adding cationic polyacrylamide, alkyl ketene dimer, and paraffin emulsion. The degradation process of cellulose film was studied using a UV degradation test and an acid-base degradation test system. The results showed that after 40 days of UV degradation, the degradation rate of Salix/wheat straw fiber degradable film could reach 6.66%. The tensile strength could still maintain 2.878 KN/m. The results of the brightness change index (ΔL) and color overall change index (ΔE) showed that the surface of the Salix/wheat straw fiber degradable film had been successfully partially degraded. After 4 days of alkaline degradation, the degradation rate could reach 11.89%. After 4 days of acid degradation, the degradation rate could reach 14.64%. At the same time, the specific degradation process of Salix/wheat straw fiber degradable film was further studied by infrared spectroscopy and scanning electron microscopy. This work provides a new method for the study of agricultural degradable cellulose mulch, which is of great significance for the future development of agricultural mulch.
... Film ranging from packaging to biomedical applications [122] PHA as solid substrate Wastewater denitrification [28] PHA/PLA Microstructures for biomedical and functional applications [123] P(3HB)/mcl-PHA blend Packaging products and highvalue biomaterials [124,125] Wood chip reinforced PLA/PHA blend Sheet film [126] Poly(butylene adipate-coterephthalate)/PHA Biodegradable mulch film [127] Wood flour/PHA Micro-screw extrusion system in filament printing [128] Acrylic acid grafted PHA and spent coffee ground ...
The current processes for producing polyhydroxyalkanoates (PHAs) are costly, owing to the high cost of cultivation feedstocks, and the need to sterilise the growth medium, which is energy-intensive. PHA has been identified as a promising biomaterial with a wide range of potential applications and its functionalization from waste streams has made significant advances recently, which can help foster the growth of a circular economy and waste reduction. Recent developments and novel approaches in the functionalization of PHAs derived from various waste streams offer opportunities for addressing these issues. This study focuses on the development of sustainable, efficient, and cutting-edge methods, such as advanced bioprocess engineering, novel catalysts, and advances in materials science. Chemical techniques, such as epoxidation, oxidation, and esterification, have been employed for PHA functionalization, while enzymatic and microbial methods have indicated promise. PHB/polylactic acid blends with cellulose fibers showed improved tensile strength by 24.45-32.08 % and decreased water vapor and oxygen transmission rates while PHB/Polycaprolactone blends with a 1:1 ratio demonstrated an elongation at break four to six times higher than pure PHB, without altering tensile strength or elastic modulus. Moreover, PHB films blended with both polyethylene glycol and esterified sodium alginate showed improvements in crystallinity and decreased hydrophobicity.
... Making the soil surface resistant to wind force using soil stabilizers is one of the methods applied to control wind erosion. Soil stabilizers should be able to bind soil particles to the soil surface and thus improve the stability through interconnecting of the particles [7]. ...
The abilities of Dubb Humic Acid (DHA) composites with Lignin and Lignosulfonate as stabilizers to reinforce soil against wind erosion. These stabilizers were obtained as value-added materials extracted from a natural waste. The properties of stabilized soils were examined, which included cation exchange capacity and organic matter amount. Influences of DHA/Lignin and DHA/Lignosulfonate were tested against wind erosion by soil stabilization and decreasing loss of soil using a wind tunnel flowing a turbulent wind of 7 m/s velocity. The soil employed in wind erosion tests was composed of sand (90.12%) and silt/clay (9.88%) particles. To explore soil stabilization influence, different weight ratios of DHA to Lignin or Lignosulfonate (1:1, 1:2, 1:3, and 1:4 w/w%) were evaluated. Also, the total solution concentration was changed from 9 to about 13 w/v% in order to find out its effect on the film forming capacity/quality. Various composites of DHA/Lignin and DHA/Lignosulfonate were applied on soil which were incubated at ambient conditions for 5–7 days and then coated soil plates were subjected to wind flowing experiments. In the simulated turbulent flow condition, loss of soil was measured for 10-min duration. Experimental results obtained for DHA/Lignin and DHA/Lignosulfonate stabilized soils were compared to untreated soil sample. It was found that all of DHA/Lignin and DHA/Lignosulfonate stabilized soils were resistant against wind erosion. Furthermore, the DHA/Lignin films were more even and exhibited much less number of cracks than DHA/Lignosulfonate films. The most homogeneous films were formed using DHA/Lignin composite in 1:2 ratio using 9 w/v% solution concentration.
... However, the slow crystallization rate and poor processability of PCL limits its application. Considering this, the main research concentrated mostly on blending modification with other bio-based materials [29][30][31]. While the research on its degradation performance has not received sufficient attention [32][33][34]. ...
Polycaprolactone (PCL) is one of the promising linear aliphatic polyesters which can be used as mulching film. Although it has suitable glass transition temperature and good biodegradability, further practical applications are restricted by the limited temperature-increasing and moisturizing properties. The rational design of the PCL structure is a good strategy to enhance the related properties. In this study, thermally-induced phase separation (TIPS) was introduced to fabricate a PCL nanoporous thin film. The introduction of a nanoporous structure on the PCL surface (np-PCL) exhibited enhanced temperature-increasing and moisturizing properties when used as mulch film. In detail, the average soil temperature of np-PCL was increased to 17.81 °C, when compared with common PCL of 17.42 °C and PBAT of 17.50 °C, and approaches to PE of 18.02 °C. In terms of water vapor transmission rate, the value for np-PCL is 637 gm−2day−1, which was much less than the common PCL of 786 and PBAT of 890 gm−2day−1. As a result, the weed biomass under the np-PCL was suppressed to be 0.35 kg m−2, almost half of the common PCL and PBAT. In addition, the np-PCL shows good thermal stability with an onset decomposition temperature of 295 °C. The degradation mechanism and rate of the np-PCL in different pH environments were also studied to explore the influence of nanoporous structure. This work highlights the importance of the nanoporous structure in PCL to enhance the temperature-increasing and moisturizing properties of PCL-based biodegradable mulching film.
... The appearance of biofilm or fibrous-like of PBAT in SEM images can be seen after 39 weeks of soil burial condition. Due to biodegradation process of PBAT/TPS sample under soil burial condition, the cleavage of ester bonds by microorganism extracellular enzymes may have actually accelerated abiotic hydrolysis, resulting in more extensive degradation.38 PBAT contains crystalline butylene terephthalate (hard and rigid) and amorphous butylene adipate (soft). ...
Study on degradation behaviors of biodegradable poly(butylene adipate-co-terephthalate) (PBAT) blended with different compositions of thermoplastic starch (TPS)
under soil burial and natural weathering environments is vital in order to predict the
product service-life and planning for in situ biodegradation after product disposal. In
this article, different compositions of TPS (0%, 20%, 40%, 50%, and 60%) were compounded with PBAT using single screw extruder. The samples were characterized for
their tensile properties, fractured surface morphology, water barrier and surface
hydrophorbicity properties in order to investigate the effect of starch fractions in
PBAT blends. The degradation behavior under natural weathering and soil burial conditions was also determined during the 9 months duration by observing the change
of physical appearance, weight loss, surface morphology, chemical structural, and
tensile properties. The findings showed that the addition of TPS (20%, 40%, 50%,
and 60%) had led to a reduction in tensile strength (41.47%, 60.53%, 63.43%, and
68.53%), and reduction in elongation at break (42.92%, 92.1%, 92.23%, and 93.22%,
respectively) and water barrier properties. The findings also showed that there were
distinct degradation behavior under both conditions. Upon exposure to natural
weathering, photodegradation and Norrish type I & II occurred whereas under the
soil burial condition, hydrolytic, and enzymatic degradation take places. Sample with
the highest starch contents underwent the highest weight loss and reduction in tensile properties under both environments. The findings in this study are useful in order
to investigate the feasibility of PBAT/Tapioca starch blends for biodegradable plastic
film for various industrial applications especially in packaging and agricultural mulch.
... Direct exposure to the sunlight in an open field, which contain UV component can lead to a significant physicochemical change in the structure of biodegradable materials which either fasten or slow down the biodegradation. The effect of different type of stabilizers, which were antioxidant (Pentaerythitol tetrakis-3-(3,5-di-t-butyl-4-hydroxyphenyl)-propionate), UV absorber (2(2 0 -Hydroxy-3 0 ,5 0 -di-t-butylphenyl)-5-Chloro-benzo-triazole), and hydrolysis resistance (carbodiimide HyMaxV R 1010) additives mixed with PBAT/PHA blends for mulching films were investigated by Wang et al. [98] Among these additives, UV stabilizer (0.3%) was the most effective in protecting PBAT/PHA under an accelerated aging test (AAT) with 12 times improvement in mechanical properties. The UV stabilizer in PBAT/PHA films can absorb UV radiation energy and undergo structural transformation to provide a stabilizing effect. ...
Recently, the demands of biodegradable plastic for mulching application have vastly increased due to environmental concern, conservation of soil health and ease of residue management after growing season. The raise in demands also reflected by the increased number of studies related to biodegradable plastic mulch in the past 10 years. Biodegradable plastic mulch film has emerged as a promising alternative material for mulching due to ease of installation, offers benefits comparable to polyethylene (PE) mulch film, in situ biodegradation and able to improve soil fertility. This review sheds light on recent advances in different formulations of plastic mulch film. Formulations based on single polymer, polymer blends and polymer composites of biodegradable natural and synthetic polymeric materials particularly for mulching application were discussed. Comprehensive discussions on the performance of different formulations used for mulching material are reviewed in this review article.
The blends of poly(butylene-adipate-co-terephthalate)/poly(ethylene-vinyl alcohol) (PBAT/EVOH) with varying amounts of graphene oxide (GO) were prepared by melt mixing. The localization of GO in PBAT and at the interface was confirmed by morphological evaluation. The dual effect of GO in degradation of PBAT phase and interface improvement of PBAT/EVOH was examined by rheological measurements and models. The results showed that the improved interfacial interaction induced by GO dominates its degradation effect in PBAT. Rheological analysis revealed that the interfacial elasticity originating from GO dominates the total elasticity of the system, resulting in an increase in the final elasticity. Generalized Fractional Zener (GFZ) model was used to analyze elasticity of the polymer blend and its nanocomposites with a well fit to the experimental results. Also, the Lee–Park model was used to distinguish the effects of particle interactions as well as interface strengthening from deterioration of matrix modulus due to PBAT degradation by GO. The increased elasticity of the interface showed that the strengthening effect of GO at the interface overcomes its degradation effect. Also, the application of Coran model to analyze phase homogeneity revealed a linear increase in interfacial interaction with GO concentration.
