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Corrosion is an age-old global issue that demands advanced protection solutions, among which the nanostructured electroactive coatings are getting special attention. Herein, we demonstrated the utilization of waste tea bags as a source for producing nanocrystalline cellulose (NCC) that was further incorporated into the polyaniline (PANI) matrix to synthesize PANI/NCC composites via in situ polymerization of aniline with the addition of NCC dispersed phase. Subsequently, various anticorrosion compositions based on epoxy resin containing different proportions of PANI/NCC were formulated and coated over mild steel substrate. Their corrosion inhibition performance was measured through Tafel polarization curves and electrochemical impedance profiles under saline environment (3.5% NaCl electrolyte). It was observed that the mild steel coated with epoxy having 1.5 wt% loading of PANI/NCC composite showed significantly high corrosion inhibition efficiency (99%), which is ascribed to the combined effect of barrier action of NCC to corrodents (water/oxygen) as well as ennoblization by PANI. [ABSTRACT FROM AUTHOR]

Polyaniline (PANI) and Saccharina Japanica seaweed (kelp) biochar (KBC) composites were synthesized in-situ through polymerization. This study presents a novel approach to the degradation of sulfamethoxazole (SMX), a prevalent antibiotic, using a PANI-KBC composite to activate peroxymonosulfate (PMS). Extensive characterizations of the PANI-KBC composite were conducted, resulting in successful synthesis, uniform distribution of PANI on the biochar surface, and the multifunctional role of PANI-KBC in SMX degradation. A removal efficiency of 97.24% for SMX (10 mg L−1) was attained in 60 min with PANI-KBC (0.1 g L−1) and PMS (1.0 mM) at pH 5.2, with PANI-KBC showing effectiveness (>92%) across a pH range of 3.0–9.0. In the degradation of SMX, both radical (SO 4 •− and •OH) and non-radical (1O 2 and electron transfer) pathways are involved. The reaction processes are critically influenced by the roles of SO 4 •−, 1O 2 and electron transfer mechanisms. It was suggested that pyrrolic N, oxidized sulfur (−C−SO 2 −C−), structural defects, and O−C O were implicated in the production of 1O 2 and electron transfer processes, respectively, and a portion of 1O 2 originated from the conversion of O 2 •−. The study evaluated by-product toxicity, composite reusability, and stability, confirming its practical potential for sustainable groundwater remediation. [Display omitted] • The PANI-KBC composites were effectively utilized in eliminating SMX from groundwater. • The combined effects of SO 4 •−, •OH, 1O 2 and electron transfer predominantly facilitated the degradation of SMX. • The surface interaction of PANI-KNC improved the degradation of SMX. • Pyrrolic N, oxidized sulfur (−C−SO 2 −C−) and structural defects were the active sites. • The PANI-KBC/PMS system significantly reduced the toxicity of SMX by-products. [ABSTRACT FROM AUTHOR]

To explore the high performance of supercapacitors, oxygen deficient Fe2O3/N, P co-doped carbon (N-Fe2O3/NPC) composites were successfully fabricated by the one-step calcination of a precursor of FeOOH/polyaniline composites via a simple strategy of introducing oxygen vacancy (denoted as oxygen defects). The influences of carbonization temperature and carbonization time on the electrochemical properties of the N-Fe2O3/NPC composites were investigated. The results show that N-Fe2O3/NPC-450-2h exhibits high capacitance (605 mF cm−2 at a current density of 5 mA cm−2) and cycle life (100% after 2000 cycles). The assembled N-Fe2O3/NPC-450-2h-based symmetrical supercapacitor possesses a capacity retention rate of 100% after 5500 cycles at a current density of 10 mA cm−2. In addition, the symmetrical supercapacitor shows a maximum energy density of 0.0148 mWh cm−2 (0.255 mWh cm−3) when the power density is 0.8 mW cm−2 (13.8 mW cm−3). N-Fe2O3/NPC-450-2h has broad application prospects as an electrode material for long-life symmetrical supercapacitors. [ABSTRACT FROM AUTHOR]

Summary: Bioaugmentation is considered a potential tool to boost the performance of microbial fuel cells (MFCs) by modifying electrodes with biopolymers. However, research on biopolymers in MFCs to treat real wastewater is very limited. Polylactic acid (PLA) is a biopolymer obtained from renewable feedstock, extensively being used in the form of nanofibers due to its biocompatible nature, while polyaniline (PANI) is a favorite candidate for electrode modification in MFC under its good electrical conductivity and stability. Interestingly, PANI‐based degradable nanofibers are known to support cell adhesion and proliferation. The current work is, therefore, aimed at finding a new environmentally benign composite material using electrospun PLA nanofiber decorated with in situ polymerized PANI. The resultant PANI/PLA electrode was tested for its efficacy as anode with domestic wastewater‐fed MFCs against conventional graphite felt. The flexible anode outperformed the flat graphite felt anode displaying a 92.32% decrement in charge transfer impedance and 8‐fold increase in maximum power density with excellent cell adherence under which simultaneous COD removal of 91.7% was also achieved. The present study has successfully added a new dimension to the design of sustainable anode material to enhance microbial binding and achieve high power output, revealing the enormous potential of biopolymer‐based MFCs in the future. By switching to the biopolymer flexible electrode that rivals its traditional polymers, the MFCs demonstrate promise to be a vital tool accessible in the remotest part of the world lacking electrical infrastructure for simultaneous clean water and electricity generation. Highlights: 8‐fold increase in power density in real wastewater‐fed MFCs using novel PANI/PLA anode.91.7% COD removal from domestic wastewater using mediator‐less MFCs.Pseudocapacitive nature displayed by the biopolymer‐based anode.Enhanced bio‐synergistic interaction between wastewater‐borne microbial biofilm and bioaugmented anode. [ABSTRACT FROM AUTHOR]

Conducting polymeric composites have attracted great attention over the last years because of their potential uses in chemical, electronic and optical devices, and as catalysts as well as in adsorption processes. Chemical synthesis of polyaniline (PANI) and polyaniline-SiO2 composite and their adsorptive performance were reported in the present work. These materials were prepared and evaluated for their methylene blue (MB) dye adsorption characteristics from aqueous solution. Adsorption equilibrium kinetic and thermodynamic experiments of MB onto PANI and PANI/SiO2 were studied. The effects of initial dye concentration, contact time and temperature on the adsorption capacity of PANI/SiO2 for MB have been investigated. The pseudo-first order and pseudo-second order kinetic models were used to describe the kinetic data. It was found that adsorption kinetics followed the pseudo-second order at all of the studied temperatures. The Langmuir, Freundlich and Dubinin Raduschkevich adsorption models were used for the mathematical description and the HyperChem v8 software was exploited to propose a possible mechanism of the adsorption process. [ABSTRACT FROM AUTHOR]

Polyaniline (PANI) is one of the most studied intrinsically conducting polymers. Polyaniline inclusion with different porous materials is a very attractive research area. In this review, the preparation, properties, and applications of PANI composites have been summarized. PANI was found to be promising among the other conducting polymers and incorporated with different materials like graphene, graphene oxide, metal oxide, carbon, carbon nanotube, silica, silicon dioxide, biomolecules, and metal organic frameworks to enhance the area of application. Metal organic framework (MOF) itself has a vast area of application so incorporation of PANI with MOF can open up tremendous possibilities. An attempt has been made to draw attention to the recent spotlight research area that is, PANI‐MOF composites. [ABSTRACT FROM AUTHOR]

This work reports the preparation of a conductive composite film, from one of the most conductive polymers, polyaniline (PAn), and a methacryloyl group attached-poly(vinyl alcohol) (M-PVA), in a few straightforward process steps. First, the -OH groups of PVA were modified through trans-esterification reaction using glycidyl methacrylate (GMA), in the presence of N, N, N, N-tetramethylethylenediamine (TEMED) as a catalyst at 60 ℃. After casting the M-PVA into the film in the organic media, the polymerization of aniline was performed onto this surface using APS as an oxidant in 1.0 M HCl. The effects of conditions, including the concentrations of MPVA used for film-casting, and aniline, were investigated on PAn content (%) and conductivity. It was observed that the conductivity of the thin and almost transparent composite films (containing 17.5% of PAn) reached to 10-4 Scm-1 . The characterization of the samples was conducted by ATR-FTIR, contact angle-wetting time measurements, and SEM-EDX techniques. The usability of the conductive composite film in the electromagnetic interference (EMI) shielding was examined within 30 MHz-3 GHz, through the measurement of electromagnetic interference shielding effectiveness (EMSE) and relative shielding efficiency values of absorption (Ab) and reflection (Re). Twice PAn deposited-composite film showed an average 5.6 dB EMSE value that corresponds to 71% of shielding through the Ab mechanism, dominantly. [ABSTRACT FROM AUTHOR]

A simple, cost‐effective, and novel chemical sensor for ammonia (NH3) gas detection was developed from polyaniline (PANI)/quail eggshell (QES) composites. QES is a natural waste enriched in calcium carbonate. In this work, pure PANI was synthesized from chemical oxidation method and PANI/QES composites were prepared from physical mixing of QES with the synthesized PANI at different mass ratio. A series of complementary techniques including Fourier transform infrared and ultraviolet‐visible spectrometers, scanning electron microscope with energy dispersive detection coupled with mapping, thermogravimetric analysis, and X‐ray diffractometer were used to characterize the physicochemical and textural properties of the biocomposites. From the results, PANI/QES composite with a mass ratio of 1 exhibited the lowest NH3 detection limit of 5.24 ppm with a linear correlation coefficient (R2) of close to unity (0.9932) between the signal and NH3 gas concentration. As a whole, the PANI/QES biocomposites synthesized from this work exhibited excellent selectivity toward NH3 gas even in the presence of other gas impurities, such as acetone, ethanol, and hexane. For the sensor reusability, the PANI/QES biocomposites can be reused in the application of NH3 gas detection for at least 4 cycles. [ABSTRACT FROM AUTHOR]

Summary: A new system based on Polyaniline‐Acetylene black‐Copper cobaltite composite has been prepared and affirmed by XRD, UV, SEM, FTIR, and EDS characterizations. The rod‐like texture of ternary hybrid system offered excellent electrochemical activity in comparison to single and binary systems. CV and CD results revealed outstanding redox behavior of the ternary hybrid electrodes. Ternary electrode (PACC) presented the highest specific capacitance value of 690 F/g at 1 mA/cm2 current density. PACC electrode based symmetric supercapacitor had a specific capacitance of 137.25 Fg‐1 at 1 mA/cm2 of current density. PACC symmetric supercapacitor had the highest specific power and specific energy of 3308.85 W.kg‐1 and 19.064 Wh.kg‐1, respectively. The ternary system provides less charge transfer resistance values compared to all other systems. Thermal stability of the ternary composite is way better than polyaniline, which is due to the contribution of copper cobaltite and acetylene black. The overwhelming characteristics of the ternary hybrid composite bring it to the limelight as an excellent candidate in the field of supercapacitors. [ABSTRACT FROM AUTHOR]

• PANI/Acetylene black/CoFe 2 O 4 hybrid system was synthesized. • Ternary composite demonstrated a specific capacitance of 747.64 F/g at 1 mA. • The highest specific energy of ternary system was found to be 39.218 Wh/kg. • Ternary hybrid system showed the highest capacitance retention of 81% after 6000 cycles. • Ternary system has the least charge transfer resistance value of 2.3 Ω. A novel ternary polyaniline-acetylene black-cobalt ferrite hybrid system was synthesized and confirmed by XRD, FTIR, UV, SEM, EDS analysis. Ternary composite electrode (PACOF) and the corresponding symmetric supercapacitor had high specific capacitance of 747.64 and 282.35 F/g, respectively at 1 mA. The ternary electrode based symmetric system had 39.218 Wh/kg and 3042.77 W/kg of specific energy and specific power, respectively. The ternary system has the least charge transfer resistance value of 2.3 Ω. Ternary hybrid system has the highest specific capacitance retention (81%) after 6000 cycles. The superior performance of ternary composite was due to the synergistic effects between individual components. [ABSTRACT FROM AUTHOR]

Polyaniline (PANI)/single-walled carbon nanotube (SWCNT) composite films with good uniformity were prepared by in situ plasma polymerization of aniline containing SWCNTs. A unique method was used to inject the monomer and SWCNTs simultaneously into the plasma reactor. Chemically pre-functionalized SWCNTs-COOH and pristine SWCNTs were used in this study. Both types of the SWCNTs were plasma functionalized during their path to the substrate through the microwave plasma, which led to a uniform dispersion within the PANI matrix. The structure and morphology of the films were characterized by the Fourier transform infrared, X-ray diffraction, atomic force microscopy, and scanning electron microscopy. The Fourier transform infrared method confirmed the chemical bonding and the formation of the nanocomposite. While the X-ray diffraction results indicated that the composite has a relatively high ordered crystalline structure, which is expected to reveal high electrical conductivity. The atomic force microscopy micrographs specified a uniform distribution of the SWCNTs in PANI matrix with no aggregations and low roughness average, whereas the scanning electron microscopy micrographs revealed that SWCNTs of both kinds were completely coated by PANI and well dispersed in a continuous polymer matrix forming a conductive network. Films conductivity was examined by the Hall effect; the PANI/SWCNT composite showed a conductivity of 25 S/cm with using pristine SWCNTs of 1.5 wt% and 50 S/cm for composite using chemically pre functionalized SWCNTs-COOH of the same loading percentage, compared to that of pure PANI of 10-8 S/cm. It is concluded that the improved conductivity of the PANI/SWCNT composite films is due to the strong interaction between SWNTs and PANI, which simplifies the effective degree of electron delocalization. [ABSTRACT FROM AUTHOR]

This study was focused on the photocatalytic activity of polyaniline (Pani)/iron doped titanium dioxide (Fe–TiO2) composites for the degradation of methylene blue as a model dye. TiO2 nanoparticles were doped with iron ions (Fe) using the wet impregnation method and the doped nanoparticles were further combined with Pani via an in situ polymerization method. For comparison purposes, Pani composites were also synthesized in the presence undoped TiO2. The photocatalyst and the composites were characterized by standard analytical techniques such as FTIR, XRD, SEM, EDX and UV–Vis spectroscopies. Fe–TiO2 and its composites exhibited enhanced photocatalytic activity under ultraviolet light irradiation. Improved photocatalytic activity of Fe–TiO2 was attributed to the dopant Fe ions hindering the recombination of the photoinduced charge carriers. Pani/Fe–TiO2 composite with 30 wt.% of TiO2 nanoparticles achieved 28% dye removal and the discoloration rate of methylene blue for the sample was 0.0025 min−1. FTIR, XRD, SEM, EDX and UV–Vis spectroscopies supported the idea that Fe ions integrated into TiO2 crystal structure and Pani composites were successfully synthesized in the presence of the photocatalyst nanoparticles. The novelty of this study was to investigate the photocatalytic activity of Pani composites, containing iron doped TiO2 and to compare their results with that of Pani/TiO2. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Fibrillar structure of pure PANI and PANI doped with sulphonic acids (SA) are synthesized by interfacial polymerization. • A comparative study on the structural, morphological and dielectric properties of undoped and doped PANI are studied. • The charge transport properties are studied based on the dielectric and AC conductivity. • The charge transport mechanisms in the composites are discussed. Abstract Present work is primarily emphasized on the study of dielectric properties of sulphonic acids (SA) incorporated polyaniline (PANI). SA's function as dopants as well as surfactants for PANI. The PANI and PANI-SA samples are prepared by interfacial technique. The three composites prepared with three SA's (camphor sulphonic acid (CSA), dodecylbenzene sulphonic acid (DBSA) and polystyrene sulfonic acid (PSSA)) are characterized by X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR), field effect scanning electron microscopy (FESEM) and thermogravimetric analysis (TGA) and differential thermogram (DTG) prior to dielectric studies. The results of PANI not incorporated with SA are also shown for comparison. XRD shows enhancement of crystallinity on SA doping. FTIR confirms the molecular structure with enhanced oxidation states on SA doping. FESEM shows fibrillar morphology with reduced fiber diameter from 86 nm in pure PANI to minimum of 50 nm in one of the composites. TGA and DTG results show better thermal stability on SA doping. The dielectric and AC conductivity measurements of the undoped and dopedPANI are studied inthe frequency range of 42 kHz - 2 MHz and in the temperature range of 300 K–330 K. The dielectric constant for all the PANI composites increases with increase in temperature which indicates increase in mobility of the electric dipoles in the polymers. The dielectric constant for DBSA doped PANI is nearly 5000 which is much higher in context to interfacially polymerized nanofibres compared to that of undoped PANI where this value is about 800. Electric modulus studies show relaxation peaks in imaginary modulus spectra which ascertains about the type of relaxation process. The AC conductivity of the composites is found to be much higher than that of undoped PANI. The electrical conductivity increases with increase of temperature. This is suggested to be caused due to the activated trapped charge carriers. [ABSTRACT FROM AUTHOR]

While polyaniline holds a great promise as an electrode material for pseudocapacitors, its poor stability against charge/discharge hinders its practical applications. In this work, polymerization of aniline was conducted in the presence of commercial carbon black VXC-72 to prepare polyaniline/VXC-72 composite electrodes. Results showed that the stability of the polyaniline/VXC-72 composite electrode was drastically improved with over 90% capacitance retention after 10,000 cycles at a current density of 2 A g −1 . It was found that VXC-72 particles played an important part in the chemical oxidative polymerisation process – they served not only as nucleation sites on which polymerization underwent to form polyaniline but also determined the morphology of the resultant solid product. The polyaniline/VXC-72 composite electrode materials with different contents of VXC-72 exhibited different morphologies and electrocapacitive performances. This research provides guidelines for designing polyaniline-carbon black composite electrode materials with an excellent stability against cycling, high capacitance, and low cost. [ABSTRACT FROM AUTHOR]

Electrochemical properties of functionalized MWCNT/polyaniline doped with metal oxide (TiO 2 , RuO 2 ) nanoparticles were explored. Successful synthesis of MWCNT, TiO 2, RuO 2 , PANI, MWCNT-PANI-TiO 2 , and MWCNT-PANI-RuO 2 nano materials were confirmed using suitable characterization techniques. Successful modification of gold (Au) electrode with these nanoparticles was confirmed using electrochemical techniques such as cyclic voltammetry (CV) and electrochemical impedance spectroscopy. Au-MWCNT-PANI-TiO 2 and Au-MWCNT-PANI-RuO 2 gave the best electron transport properties towards the oxidation of epinephrine (EP) compared with other electrodes investigated. The Tafel values 0.448 and 0.442 V/decade for Au-MWCNT-PANI-TiO 2 and Au-MWCNT-PANI-RuO 2 electrodes respectively in (EP) suggest adsorption due to analyte oxidation intermediates products. The linear calibration plot was obtained for EP at concentrations range 4.9 to 76.9 μM. The limits of detection of EP were estimated to be 0.16 and 0.18 μM for Au-MWCNT-PANI-TiO 2 and Au-MWCNT-PANI-RuO 2 electrodes respectively. The interference study using DPV showed clear peak separation for amino acid (AA) and EP. Therefore, the modified electrodes can selectively detect epinephrine without interference from ascorbic acid signal. The analytical performance of the fabricated sensors has been evaluated for detection of epinephrine (EP) in a pharmaceutical sample with satisfactory results. [ABSTRACT FROM AUTHOR]

Polyamide 6 (PA6), polyacrylonitrile (PAN) and cellulose acetate (CA) have been prepared by electrospinning. Electrospun CA nanofibres are deacetylated to obtain cellulose nanofibres. Polyaniline (PANI)-based composite nanofibres have been prepared by in situ polymerization of aniline with the electrospun PA6, PAN and cellulose nanofibres separately. Structural and chemical examinations of the prepared composite nanofibres are conducted by scanning electron microscope and Fourier transform infrared spectroscopy. The sensing properties of the PANI-based composite nanofibres to ammonia are evaluated by a home-made sensor test system. It is found that PA6/PANI, PAN/PANI and cellulose/PANI composite nanofibres respond to ammonia. Cellulose/PANI composite nanofibres show the best ammonia sensing properties among them, whose response to 250 ppm ammonia is found to be 2.70, followed by PA6/PANI (1.52) and PAN/PANI's (1.23). [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the removal efficiency of in situ synthesized composites consisted of emeraldine base and clinoptilolite on copper ions removal from aqueous medium. Two composite materials (Composite I and Composite II) with different quantity of clinoptilolite were synthesised. The influence of the composite dosage, the contact time and the initial copper ions concentration has been studied. The results show that the significant removal of the copper ions becomes at the first minute of the contact between the composite material and the aqueous medium and the longer contact time leads to increasing of the copper ions removal. The removal efficiency at the 1st minute was 57.5% and 77.3% using Composite I and Composite II, respectively. Maximum removal efficiency of 87.3% and 96.8% was achieved at the same dosage of Composite I and Composite II, respectively, at contact time of 360 minutes and temperature of 24 °C. [ABSTRACT FROM AUTHOR]

The polyaniline/copper oxide (PANI/CuO) nanocomposite was prepared by mixing solutions of polyaniline and copper oxide nanoparticles in dimethyl sulfoxide (DMSO). The synthesized polymer nanocomposites were characterized by X-ray powder diffraction (XRD), scanning electron microscope (SEM) and UV–visible spectroscopy. The characteristic peaks in XRD and UV–visible spectra confirmed the presence of CuO in the polymer structure. SEM images indicated morphological changes in the composite matrix as compared to the pristine PANI. The DC conductivity measurements were performed using two-probe method for various temperatures. AC conductivity and dielectric response of the composites were investigated in the frequency range of 102–106Hz using LCR meter. Dielectric permittivity ϵ′(w) and dielectric loss factor ϵ′′(w) were investigated. It was observed that ϵ′(w) and ϵ′′(w) decrease with increase in frequency at all temperatures. At a particular frequency it is observed that both ϵ′(w) and ϵ′′(w) increase with increase in temperature. It was also observed that AC conductivity increased with increase in frequency and temperature.

The adsorption technique is widely applied for the removal of pollutants from wastewater, especially for toxic or non-biodegradable wastewater. In recent years, the production of alternative adsorbents to replace costly adsorbents has been paid more attention to in literature. Polyaniline/beidellite (PAn + Bei) composite material as an absorbent, which is efficient and low cost can easily be prepared via H 2 SO 4 , KIO 3 and aniline. This paper deals with color and total organic carbon (TOC) removal of biologically treated bakery yeast wastewater (BYW) using the PAn + Bei composite material by adsorption processes. The effects of experimental variables were chosen as the initial pH (pH i ), sorbent dosage ( m s ), contact time ( t c ) and mixing speed ( s ) by a batch sorption process. It was found that by increasing the adsorbent dosage (0.025–0.400 g/50 ml of composite dosage), contact time (2–240 min) and decreasing the pH i (9–3) improved the color and TOC removal efficiencies. The optimum color and TOC removal efficiencies were obtained as 88.7% and 63.3% at 0.400 g/50 ml of adsorbent dosage, a pH i of 3, 240 rpm, and 240 min. In addition, a pseudo-second order kinetic model was proposed to correlate the experimental data. To understand the removal mechanism and characterize the surface of the PAn + Bei composite material, size exclusion chromatography (SEC), BET surface analysis, fourier transform infrared spectroscopy (FTIR) analysis, scanning electron microscope (SEM), thermal gravimetric analysis (TGA), and differential scanning calorimetry (DSC) were employed. As a consequence, the proposed mechanism for the removal by PAn+Bei composite material seems to be driven by an ion exchange process. [ABSTRACT FROM AUTHOR]

The frequency dependence of dielectric constant for composites of polyaniline (PANI) and multi-walled carbon nanotube (MWCNT) with different degree of functionalization is studied at low temperature (down to 4.2 K) and magnetic field (up to 3 T) applied both in parallel and perpendicular direction of ac electric field. A relaxation phenomenon is observed in all the MWCNT/PANI composites by applying magnetic field in both the directions, below 103 Hz. However, PANI does not show any relaxation peak with applied magnetic field in either direction. The relaxation peak frequency does not depend on the strength of magnetic field but it varies with temperature and degree of functionalization of MWCNT in composites. This relaxation phenomenon occurs due to the inhomogeneity of the medium of two highly mismatched conductive materials at low temperatures. The results are explained in the light of Parish and Littlewood theory about magnetocapacitance in nonmagnetic composite. • Dielectric relaxation is observed in PANI and functionalized MWCNT composites by applying magnetic field. • PANI/fMWCNT composites are an inhomogeneous and highly mismatched conductive material at low temperature. • Dielectric relaxation frequency shifts by varying space charge polarization at interface of PANI/fMWCNT and temperature. • Negative dielectric loss is observed below the dielectric relaxation frequency. • Relaxation frequency does not shift with increasing magnetic field. [ABSTRACT FROM AUTHOR]

ABSTRACT In general, the high electrical conductivity (EC) comes into conflict with the good flexibility and high strength of carbon nanotube (CNT)/polyaniline (PANI) composites. In other words, a high CNT content will bring about a high EC but lead to a low flexibility and strength due to the CNT-constrained matrix deformation and CNT aggregation. In this work, a highly conductive, flexible and strong CNT/PANI composite film prepared via a facile solvent-evaporation method is readily obtained by a cold stretching. The cold stretching is conducted at room temperature for the CNT/PANI film. It is observed that the cold stretching process leads to an unexpectedly enhanced EC. The as-obtained EC of 231 S/cm is much higher than that (2 -50 S/cm) of the previously reported CNT/PANI composite films. Meanwhile, the strength is obviously improved over that of the pure PANI film and the good flexibility is maintained to a high degree by the introduction of a proper CNT content. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 1575-1585 [ABSTRACT FROM AUTHOR]

A novel polyaniline composite was prepared by in situ ring-opening polymerization of ε-caprolactone in the presence of chemically modified polyaniline nanoparticles (PANI-NPs) using Sn(Oct) 2 as an initiator, which exhibited a high solubility in organic solvent to enable the fabrication of stable honeycomb-patterned thin films by casting the PANI composite solutions under humid conditions. The chemically modified PANI-NPs were produced from the polymerization of aniline in the cationic surfactant of cetyl trimethyl ammonium bromide (CTAB). The polyaniline composites were characterized via Fourier transform infrared, ultraviolet–visible spectroscopy, X-ray diffraction, transmission electron microscopy, and thermogravimetry. The analyses indicated that the PANI-NPs were well incorporated in the poly(ε-caprolactone) (PCL) backbone. The patterned PANI composite films showed high DC conductivity up to 10 −2 S/cm, which can be useful in applications such as bio-sensing, bio-nanotechnology, biological science, and medicine. [ABSTRACT FROM AUTHOR]

Abstract: A new method involving laccase-mediator system has been developed for environmentally friendly synthesis of polyaniline/multi-walled carbon nanotubes (PANI/MWCNT) composite. Fungal laccase, potassium octocyanomolibdate (4+) and atmospheric oxygen served as catalyst, redox-mediator and terminal oxidant, respectively. The structure, morphology and electrical conductivity of composites with different PANI content were investigated. The energy storage of enzymatically obtained composite consists of an electrical double layer capacitance as well as pseudocapacitance of conducting polymer. The obtained PANI/MWCNT composite with PANI content ca. 49wt.% had high specific capacitance and cycle stability during doping/dedoping. The specific capacitance of this composite measured by cyclic voltammetry technique with potential scan rate of 5 mV/s was ca. 440 F/g. The specific capacitance of the composite decreased by less than 7% of its maximum value after 1000 scan cycles between -0.1 and 0.7V. Supercapacitor (SC) shell was made from flexible adhesive tape (regular Scotch tape) and current collector was formed after its separation from the surface of graphite foil. The ethanol dispersion of PANI/MWCNT composite was deposited on the current collector surface. The gel polymer electrolyte (polyvinyl alcohol in 1M phosphoric acid) was employed as both electrolyte medium and separator. The energy and power densities under an operating window of 0.7V were ca. 7.03 Wh/kg and 5.2kW/kg, respectively. [Copyright &y& Elsevier]