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A new polyaniline/multi-wall carbon nanotube (PANI/MWNT) composite has been successfully synthesized by an "in-situ" polymerisation process; Raman studies indicate a site-selective interaction between the quinoid ring of the polymer and the MWNTs opening the way for charge transfer processes; transport measurements clearly reveal drastic changes in...
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Paper sensors are flexible, disposable, low cost and can be employed for smart paper applications. A facile method of fabricating paper based sensors for room temperature ammonia vapor detection is reported. Purified and solution processed single walled carbon nanotubes (SWCNT) were deposited on paper using vacuum filtration method and used as chem...
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... Ω -1 cm - 1 The measured conductivity of (PANI-CNC) corresponds to a high range of semiconductors (10 -4 S/cm < σ semiconductor < 1 S/cm), demonstrating a synthesis of a PANI/CNC composite with electronic properties improved. According to FTIR characterization, PANI-CNC synthesis by an In-situ process leads to efficient interactions between PANI quinoid ring and CNCs and facilitate the charge transfer processes between the two components [29]. On the other hand, when PANI-CNC particles is used as reinforcement in PP matrix at 0.5% and 1%, it is observed that the conductivity is almost the even. ...
Sustainable development and biomass valorization are a primary means of reducing the non-renewable resources consumption and an opportunity to exploit the agricultural and forestry sectors where biomass as a renewable resource will play an important role. Cellulose is the most abundant bio-renewable material and its unique structure generates nanoparticles known as cellulose nanocrystals (CNC). Cellulose nanomaterials show a great promise for various applications therefore with a relatively low loading level, significant improvements on mechanical properties of nanocomposites could be obtained, but CNCs have a strong tendency to agglomerate and its hydrophilic characteristic leads to interfacial incompatibility with non-polar polymer matrices. In this work, polyaniline (PANI) is used as a support for Cellulose nanocrystals dispersion on Polypropylene (PP) matrix. Cellulose nanocrystals were obtained according to an experimental protocol at several stages and Polyaniline was deposited on CNC's surface during polyaniline synthesis in CNC's suspension. The obtained CNC/PANI nanoparticles were incorporated into the polypropylene matrix by melting compounding technique. Polypropylene nanocomposites and PANI/CNC particles were characterized with different techniques: FTIR, AFM, electrical conductivity and mechanical properties to study and assess how polyaniline and CNC affect microstructure, morphology and electrical properties of PP. Characterization technique showed that PANI was successfully synthesized on CNC's surface and PANI/CNC material is a semiconductor. The enhanced mechanical properties of PP/PANI-CNC nanocomposites indicates a good dispersion of CNCs particles on PP matrix.
... The pronounced benzenoid band combined with the mode softening of both bands to lower energy indicates a stabilization of the benzenoid structures through interaction with [Fe(Htrz) 2 (trz)](BF 4 ). The N-H stretch associated with PANI at around 3300 cm −1 is suppressed in [Fe(Htrz) 2 (trz)](BF 4 ) plus PANI likely due to charge transfer interactions previously observed in samples of PANI and multiwalled carbon nanotubes [33]. Its intensity is proportional to the extent of H-bonding, which is expected to weaken in [Fe(Htrz) 2 (trz)](BF 4 ) plus PANI contrary to experiment. ...
Adding Fe3O4 nanoparticles to composites of [Fe(Htrz)2(trz)](BF4) spin-crossover polymer and polyaniline drives a phase separation of both and restores the molecular structure and cooperative effects of the spin-crossover polymer without compromising the increased conductivity gained through the addition of polyaniline. We observe an increased on-off ratio for the DC conductivity owing to an enlarged off state resistivity and a 20 times larger AC conductivity of the on state compared with DC values. The Fe3O4 nanoparticles, primarily confined to the [Fe(Htrz)2 (trz)](BF4 ) phase, are ferromagnetically coupled to the local moment of the spin-crossover molecule suggesting the existence of an exchange interaction between the both components.
... Ω -1 cm - 1 The measured conductivity of (PANI-CNC) corresponds to a high range of semiconductors (10 -4 S/cm < σ semiconductor < 1 S/cm), demonstrating a synthesis of a PANI/CNC composite with electronic properties improved. According to FTIR characterization, PANI-CNC synthesis by an In-situ process leads to efficient interactions between PANI quinoid ring and CNCs and facilitate the charge transfer processes between the two components [29]. On the other hand, when PANI-CNC particles is used as reinforcement in PP matrix at 0.5% and 1%, it is observed that the conductivity is almost the even. ...
In petroleum exploration, cellulose derivatives such as carboxymethylcellulose (CMC) are frequently used in drilling, cementing and fracturing fluids. However, under extreme drilling conditions, these additives have limited performance. In this regard, cellulose nanocrystals particles (CNCs) which are also derived from cellulose material are a suitable candidate due to their shear thinning rheology and thixotropy properties, even at low concentrations, among so many properties thanks to their crystalline structure and their nanometric dimensions.
In this work, hydrolyzed fibers from industrial cotton are acetylated using acetic anhydride and sulfuric acid as catalysts, with the aim to modify surface properties of the obtained CNCs without changing their fiber structure and morphology. FTIR analysis pointed out the acetylation success of the obtained nanocrystals whose dimensions were found to be unaltered by the modification process. SEM images of cotton nanocrystal indicate that CNC c surface modification preserves the nanoscale dimensions of the nanoparticles. Also, TGA analysis showed thermal stability for the acetylated CNC c .
... Nowadays, many methods for the production of nanocomposites based on conjugated polymers and carbon materials as electroactive coatings for hybrid electrodes have been developed [24,25]. Oxidative polymerization of the monomer on the surface of carbon materials, which allows for obtaining a homogeneous polymer coating, seems to be the most promising [26,27]. Polyaniline, which is prepared using the oxidative polymerization of aniline in aqueous solutions of acids, is the most common of these in use. ...
Hybrid composites based on electroactive polymers of diphenylamine-2-carboxylic acid (PDPAC) and highly porous carbon with a hierarchical pore structure were prepared for the first time. Activated IR-pyrolyzed polyacrylonitrile (IR-PAN-a), characterized by a highly developed surface, was chosen as a highly porous N-doped carbon component of the hybrid materials. IR-PAN-a was prepared using pyrolysis of polyacrylonitrile (PAN) in the presence of potassium hydroxide under IR radiation. Composite materials were obtained using oxidative polymerization of diphenylamine-2-carboxylic acid (DPAC) in the presence of IR-PAN-a both in an acidic and an alkaline medium. The composite materials were IR-heated to reduce the oxygen content and enhance their physical and chemical properties. The chemical structure, morphology, and electrical and thermal properties of the developed IR-PAN-a/PDPAC composites were investigated. The IR-PAN-a/PDPAC composites are thermally stable and electrically conductive. During the synthesis of the composites in an acidic medium, doping of the polymer component occurs, which makes the main contribution to the composite conductivity (1.3 × 10–5 S/cm). A sharp drop in the electrical conductivity of the IR-PAN-a/PDPACac-IR composites to 3.4 × 10–10 S/cm is associated with the removal of the dopant during IR heating. The IR-PAN-a/PDPACalk composites prepared before and after IR heating show a gradual increase in electrical conductivity by five orders of magnitude to 1.6 × 10–5 S/cm at 25–106 Hz. IR heating of the obtained materials leads to a significant increase in their thermal properties. The IR-heated composites lose half of their initial weight in an inert atmosphere at temperatures above 1000 °C, whereas for IR-PAN-a/PDPAC, the temperature range is 840–849 °C.
... The results showed that the flexural stress of CNTs (content 2%)/glass fiber (GF)/PA-6 composites increased by 36%, the thermal conductivity increased by about 42%, and the ignition time and peak HRR time were delayed by about 31% and 118%, respectively. However, if the CNTs and thermoplastic resin are directly mixed by melt blending [152], solution mixing [153], or in situ polymerization [154], the problem of CNTs agglomeration is inevitable due to the high viscosity and poor fluidity of thermoplastic resin and the strong van der Waals force and electrostatic force between CNTs. Moreover, the content of the CNTs reinforced phase is generally less than 5% [155][156][157]. ...
The mechanical properties of thermoplastic composite components in the thickness direction are insufficient to meet the requirements of aerospace and other fields as an alternative to conventional metal structural materials, restricting their use in related structural devices. The methods for improving the interlaminar mechanical properties of thermoplastic composites are reviewed in this work from two perspectives: enhancing the interface properties between fiber and resin and the properties of the interlaminar resin-rich zone. Fiber surface modification means, such as oxidation, plasma, ray irradiation, sizing agent, and carbon nanotubes are detailed introduced. Meanwhile, the effect of different forming technologies and using carbon nanotubes or buckypaper as reinforcement on interlaminar resin-rich zone mechanical properties are discussed. The advantages and disadvantages of each method are then summarized and analyzed. Future research on further improving the interlaminar mechanical properties of thermoplastic composites is prospected.
... Thereby, a morphological transition from a coil-like morphology to an extended morphology is expected at the interfacial PANI chains. 37 Additionally, the peaks at 1162 cm −1 , 1483 cm −1 and 1590 cm −1 exhibit a deeper red-shift after CSA doping, which could be traced to the reinforced π-π conjugated interactions at the PANI/MWCNT interfaces. ...
The energy-filtering effect has been widely employed to elucidate the enhanced thermoelectric properties of organic/inorganic hybrids. However, the traditional Mott criterion cannot identify the energy-filtering effect of organic/inorganic hybrids due to the limitations of the Hall effect measurement in determining their carrier concentration. In this work, a carrier concentration-independent strategy under the theoretical framework of the Kang-Snyder model is proposed and demonstrated using PANI/MWCNT composites. The result indicates that the energy-filtering effect is triggered on increasing the temperature to 220 K. The energy-filtering effect gives a symmetry-breaking characteristic to the density of states of the charge carriers and leads to a higher thermopower of PANI/MWCNT than that of each constituent. From a morphological perspective, a paracrystalline PANI layer with a thickness of 3 nm is spontaneously assembled on the MWCNT network and serves as a metallic percolation pathway for carriers, resulting in a 5.56-fold increase in conductivity. The cooperative 3D carrier transport mode, including the 1D metallic transport along the paracrystalline PANI and the 2D cross-interface energy-filtering transport, co-determines a 4-fold increase in the power factors of PANI/MWCNT at 300 K. This work provides a physical insight into the improvement of the thermoelectric performance of organic/inorganic hybrids via the energy-filtering effect.
... MWCNTs content. The addition of MWCNTs into PANI improves its electrical characteristics by accelerating charge transfer mechanisms among the two components [36]. Owing to the high aspect ratio and conducting nature of MWCNTs, they appear to function as a connecting bridge among the several conducting grains of the PANI, which are deposited on the surface of each MWCNTs. ...
Unique polyaniline (PANI)/poly(methyl methacrylate) (PMMA)/multiwalled carbon nanotubes (MWCNTs) nanocomposite polymer substrate electrodes (NPSEs) were prepared using in situ polymerization. PMMA microbeads (10 mm) were also added as fillers inside the NPSEs during polymerization. Different weight percentages of MWCNTs (1, 2, and 5 wt.%) were added to the NPSEs. The surface morphology of the PANI/PMMA/MWCNTs NPSEs was studied by scanning electron microscopy, Fourier transform infrared, and X-ray diffraction. Thermal stability was studied by thermo-gravimetric analyses and differential thermal analysis. Meanwhile, the four-probe analyzer and the solar simulator determined the electrical conductivities and photovoltaic parameters of the NPSEs based solar devices. The synthesized NPSEs with optimized compositions PANI/PMMA (1%)–MWCNTs (5%) showed superior photovoltaic performance along with improved thermal and electrical conductivities. Therefore, these NPSEs possess a future potential for the fabrication of solar devices in the field of solar energy applications.
... Recent research has been carried out to investigate the utility of polyester/glass fiber/MWCNTs composites in many fields like aerospace and automotive industries because of their light weight and high performance [3][4][5][6]. Composites based on CNTs have been widely studied using a variety of matrix materials like ceramics [4][5][6], metals [7], and polymers [8][9][10][11][12]. Breton [13] improved epoxy resin by adding different kinds of MWCNTs and subsequently mechanical characteristics of MWCNTs were tested. ...
Mechanical properties of polyester/glass fiber reinforced by multiwalled carbon nanotubes (MWCNTs) were studied. MWCNTs nano particles are mixed within resin in various weight fractions of 0.1, 0.2, 0.4 and 0.6 % using sonication. E-Glass fiber (chopped strand mat) is used in various weight fractions within the composite like 80/20 wt%, 70/30 wt%, 50/50 wt% to fabricate polyester/CSM/MWCNTs composites. The effect of the addition of MWCNTs nanoparticles on the mechanical characteristics such as hardness and tensile strength were investigated. The effect of various E-glass fiber chopped strand mat (CSM) wt.% reinforcement is also investigated. A scanning electron microscope (SEM) was used to show the nanocomposites morphological properties such as reinforcement orientation and the bonding between matrix and fiber. It was found that the addition of 0.4 wt% MWCNTs improves the mechanical properties of composites, especially the 50 wt% polyester / 50 wt% CSM composite. The tensile strength improved by 39.8%, and the hardness improved by 38%. ABSTRAK: Ciri-ciri mekanikal bagi poliester / gelas fiber diperkukuh dengan dinding berbilang karbon nanotiub (MWCNTs) dikaji. Partikel nano MWCNT telah dicampur ke dalam resin pelbagai berat pada pecahan 0.1, 0.2, 0.4 dan 0.6 % menggunakan sonikasi. Gentian Kaca-E (potongan lembaran) telah digunakan dalam pelbagai pecahan berat dalam komposit 80/20 wt%, 70/30 wt%, 50/50 wt% bagi menghasilkan komposit poliester/CSM/MWCNT. Kesan penambahan nanopartikel MWCNT pada ciri-ciri mekanikal seperti kekerasan dan kekuatan tensil diuji. Kesan pelbagai gentian Kaca-E (potongan lembaran) (CSM) wt.% bersama agen pengukuh turut dikaji. Pengimbas Mikroskop Elektron (SEM) digunakan bagi menilai ciri-ciri morfologi komposit nano seperti orientasi pengukuh dan ikatan antara matrik dan gentian. Dapatan kajian menunjukkan dengan penambahan sebanyak 0.4 wt% MWCNT dapat memperbaiki ciri-ciri mekanikal komposit terutama komposit campuran (50 wt% polyester / 50 wt% CSM). Ketahanan tensil meningkat sebanyak 39.8%, dan kekerasan telah bertambah sebanyak 38%.
... Recent research has been carried out to investigate the utility of polyester/glass fiber/MWCNTs composites in many fields like aerospace and automotive industries because of their light weight and high performance [3][4][5][6]. Composites based on CNTs have been widely studied using a variety of matrix materials like ceramics [4][5][6], metals [7], and polymers [8][9][10][11][12]. Breton [13] improved epoxy resin by adding different kinds of MWCNTs and subsequently mechanical characteristics of MWCNTs were tested. ...
Mechanical properties of polyester/glass fiber reinforced by multiwalled carbon nanotubes (MWCNTs) were studied. MWCNTs nano particles are mixed within resin in various weight fractions of 0.1, 0.2, 0.4 and 0.6 % using sonication. E-Glass fiber (chopped strand mat) is used in various weight fractions within the composite like 80/20 wt%, 70/30 wt%, 50/50 wt% to fabricate polyester/CSM/MWCNTs composites. The effect of the addition of MWCNTs nanoparticles on the mechanical characteristics such as hardness and tensile strength were investigated. The effect of various E-glass fiber chopped strand mat (CSM) wt.% reinforcement is also investigated. A scanning electron microscope (SEM) was used to show the nanocomposites morphological properties such as reinforcement orientation and the bonding between matrix and fiber. It was found that the addition of 0.4 wt% MWCNTs improves the mechanical properties of composites, especially the 50 wt% polyester / 50 wt% CSM composite. The tensile strength improved by 39.8%, and the hardness improved by 38%.
ABSTRAK: Ciri-ciri mekanikal bagi poliester / gelas fiber diperkukuh dengan dinding berbilang karbon nanotiub (MWCNTs) dikaji. Partikel nano MWCNT telah dicampur ke dalam resin pelbagai berat pada pecahan 0.1, 0.2, 0.4 dan 0.6 % menggunakan sonikasi. Gentian Kaca-E (potongan lembaran) telah digunakan dalam pelbagai pecahan berat dalam komposit 80/20 wt%, 70/30 wt%, 50/50 wt% bagi menghasilkan komposit poliester/CSM/MWCNT. Kesan penambahan nanopartikel MWCNT pada ciri-ciri mekanikal seperti kekerasan dan kekuatan tensil diuji. Kesan pelbagai gentian Kaca-E (potongan lembaran) (CSM) wt.% bersama agen pengukuh turut dikaji. Pengimbas Mikroskop Elektron (SEM) digunakan bagi menilai ciri-ciri morfologi komposit nano seperti orientasi pengukuh dan ikatan antara matrik dan gentian. Dapatan kajian menunjukkan dengan penambahan sebanyak 0.4 wt% MWCNT dapat memperbaiki ciri-ciri mekanikal komposit terutama komposit campuran (50 wt% polyester / 50 wt% CSM). Ketahanan tensil meningkat sebanyak 39.8%, dan kekerasan telah bertambah sebanyak 38%.
... PANI/CNTs nanocomposites were first time prepared in 1999 [123]. The synthesis of PANI/MWNTs composites was carried out by the chemical oxidation of aniline in acidic aqueous environments with an oxidizing agent that display site-selective interactions among the quinoid ring of the repeating units of PANI emeraldine salt and MWNTs [124]. A coaxial nanowire of a PANI/MWNTs composite prepared by electrochemical oxidation of aniline on a CNT electrode [125]. ...
Photocatalysis is an important technique that has been used to degrade/separate numerous pollutants from wastewater and for the generation of green energy such as clean hydrogen by splitting of water. In general, titanium dioxide-based photocatalyst is used in photocatalysis because of its nontoxicity, mechanical stability, high photocatalytic activity, and low price. Moreover, its large bandgap and high charge carrier recombination lead to poor photocatalytic activity. To overcome these limitations, photocatalyst based on conducting polymers (CPs) have come into the picture because it provides unique one-dimensional delocalized-electrons in their structures and has been exploited in numerous energy and environmental applications. This chapter highlights the modern developments in the improvement and characterization of photocatalyst based on CP for environment and energy applications. The detailed mechanism of photocatalytic degradation and hydrogen production is also explored. A detailed discussion of the various methods to synthesize and modify the CPs is presented here. The various challenges and future prospects of the photocatalyst based on CPs for environment and energy applications are also sightseen.
