Polyaniline/silver/cerium nitrate ternary composite: Synthesis,characterization and enhanced electrochemical properties

Polyaniline/Ag/Ce (NO₃)₃ ternary composites were prepared by in situ polymerization in a poly (2‐arcylamido‐2‐methylpropane sulfonic acid) aqueous solution. Fourier transform infrared spectroscopy and Ultraviolet‐visible spectroscopy analyses indicated that Ce ions had a conjugated interaction with N, O of polyaniline (PANI), and poly (2‐arcylamido‐2‐methylpropane sulfonic acid). By comparison with PANI and PANI binary composite, this ternary composite had a better thermal stability, a high conductivity (3.49 S/cm), a large capacitance, and a high electrochemical activity. Especially, the corrosion potential of this ternary composite can reach ?418 mV and the inhibition efficiency can be increased by 68.08%. This ternary porous composite has promising applications in capacitor, conductive materials, anticorrosion coating, and other related fields. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42785.     

Doping effects of cerium ion on structure and electrochemical properties of polyaniline

Polyaniline (PANI)/Ce³⁺ and PANI/Ce⁴⁺ composites were successfully prepared by in situ polymerization in an aqueous solution of poly(2‐acrylamido‐2‐methylpropane sulfonic acid) and characterized by Fourier transform infrared spectroscopy, ultraviolet–visible spectroscopy, X‐ray photoelectron spectroscopy, SEM, TEM and electrochemical methods. The results showed that the PANI/Ce ion composites had a high degree of sphericity, high electrical conductivity and good electrochemical performance. The conductivity of PANI/Ce(NO₃)₃ reaches a maximum of 46.76 S cm^?1 at 20 wt% of Ce(NO₃)₃. It is increased by 377% by comparison with that of pure PANI. In particular, the polarization results showed that the corrosion current density (0.47 µA cm^?2) and the inhibition efficiency (97%) of PANI/Ce(NO₃)₃ were better than the results for PANI and PANI/Ce(SO₄)₂ composite. This suggested that the PANI/Ce(NO₃)₃ composite has promising applications in conductive materials, anticorrosion coatings and other related fields. © 2017 Society of Chemical Industry     

Novel electrically conducting polyurethanes with oligoanilines: Synthesis,conductivity, and electrochemical properties

New class of conducting polyurethanes (CPUs) containing oligoanilines, namely tetraaniline (TAni) or trianiline (TriAni), in the backbone have been synthesized and characterized by formal spectral techniques. The unique properties of these CPUs, viz., electronic conductivity and electrochemical activity arising from the presence of oligoaniline units have been evaluated. The basic polyurethane backbone is derived from toluene diisocyanate, isophorone diisocyanate or hexamethylene diisocyanate, and polypropylene glycols of molecular weight 425 and 2000. In the first category of polyurethanes, the prepolymers obtained from the above reactants were chain terminated by TAni in emeraldine base oxidation state. The conductivity of these CPUs films ranged from 1.2 × 10^?5 to 1.77 × 10^?3 S cm^?1. These polymers showed lower conductivity due to the presence of nonconjugated polyurethane segments. These CPUs exhibited slightly different electrochemical activity than that of TAni. The second category of CPUs is obtained from prepolymers by chain extension with TriAni. The conductivity of these polymers is similar to the TAni analogues but are electrochemically inactive. The anticorrosion properties of two of these polymers have also been evaluated in this study. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40794.     

Study on correlation of filtration performance and charge behavior and crystalline structure for melt‐blown polypropylene electret fabrics

Melt‐blown polypropylene (PP) electret fabrics are widely used as air filter media due to the specific mechanism of electrostatic filtering. In this article, two additives, stearate and modified rosin, are doped to PP fabrics during melt‐blown process. The filtration performance of doped PP gets improved greatly, with filtration efficiency increased by 6% at room temperature but its temperature stability promoted dramatically. As a result, the filtration efficiency of doped PP still remains above 95% of its initial, whereas that of non‐doped PP only remains 58% at 110°C. By XRD characterization the structure modification is observed after doping. The crystallinity increases from 14.17% to 22.64% and 29.62%, respectively. Meanwhile, the crystallite has a smaller size, respectively, 89Å and 86Å as compared to 107Å for non‐doping in the direction vertical to lattice plane (110). This demonstrates that additive doping can give rise to larger crystallinity and more fine‐grained crystallite. Therefore, doped PP improves its charge storage behavior ascribing to expanding interface between crystallite and amorphous region and then enlarging charge trap density. Furthermore, the effect of additive doping on electret charge storage behavior is investigated by short‐circuit TSD, and the filtration performance can be explained relevantly with TSD. A charge storage profile is also adopted to illustrate that the space charge captured by charge traps is in the form of space‐charge dipole with the rigidity of crystallite. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42807.     

Synthesis and characterization of new conjugated soluble polythiophenes with excellent reversible electrochemical properties

A series of five new conjugated polythiophene (PT) derivatives containing piperidinyl groups as a side chain were synthesized by ferric trichloride oxidization. All of the polymers were soluble in common organic solvents, and their high regioregularity were confirmed by ¹H‐NMR. The weight‐average molar masses ranged from 5931 to 22,955 g/mol with a low polydispersity index ranging from 1.18 to 1.79. The fluorescence emission maximum of poly[3‐(N‐methyl propionate–4′‐piperidine)methylene–thiophene] in the films was 725 nm in the yellow–red region, higher than that of the other PT derivatives. All five polymers exhibited reversible p‐doping/dedoping (oxidation/reneutralization) processes; this indicated that these polymers could be applied in electrical equipment in the doping state. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Synthesis and electrochemical properties of hollow polyaniline microspheres by a sulfonated polystyrene template

Hollow polyaniline microspheres (HMsPANI) for supercapacitors were prepared successfully with sulfonated polystyrene microspheres as the template. The prepared electrode materials of HMsPANI consisted of nanoparticles and, thus, had a hierarchical structure. The electrochemical behaviors of the materials were investigated with cyclic voltammetry and galvanostatic charge–discharge tests. A maximum specific capacitance of 421 F/g was achieved in a 1M H₂SO₄ solution, with the potential ranging from ?0.2 to 0.8 V (vs a saturated calomel electrode), in a three‐electrode glass cell at room temperature for the HMsPANI electrode. This suggested its potential application in electrochemical capacitors. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Morphology,crystallinity, and electrochemical properties of in situ formed poly(ethylene oxide)/TiO2 nanocomposite polymer electrolytes

A method to produce nanocomposite polymer electrolytes consisting of poly(ethylene oxide) (PEO) as the polymer matrix, lithium tetrafluoroborate (LiBF₄) as the lithium salt, and TiO₂ as the inert ceramic filler is described. The ceramic filler, TiO₂, was synthesized in situ by a sol–gel process. The morphology and crystallinity of the nanocomposite polymer electrolytes were examined by scanning electron microscopy and differential scanning calorimetry, respectively. The electrochemical properties of interest to battery applications, such as ionic conductivity, Li⁺ transference number, and stability window were investigated. The room‐temperature ionic conductivity of these polymer electrolytes was an order of magnitude higher than that of the TiO₂ free sample. A high Li⁺ transference number of 0.51 was recorded, and the nanocomposite electrolyte was found to be electrochemically stable up to 4.5 V versus Li⁺/Li. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2815–2822, 2003     

Rheological properties,cure characteristics,and morphology of acrylonitrile‐based nanorubber modified epoxy

This article investigates the effects of nano carboxylic acrylonitrile butadiene rubber (CNBR‐NP) and nano acrylonitrile butadiene rubber (NBR‐NP) on the rheological properties and cure characteristics of epoxy. Dynamic mechanical behavior of carbon fiber reinforced polymer composites (CFRP) with the nanorubber‐modified matrices was also studied. Rheological study showed that NBR‐NP blends attained lower viscosity in comparison to CNBR‐NP blends and both systems exhibited shear‐thinning behavior. Scanning electron microscopy (SEM) images revealed that CNBR‐NP could be dispersed evenly within the epoxy matrix using industrial mixing process whereas partial agglomeration was observed in NBR‐NP blends. The dynamic mechanical analysis (DMA) data showed that the addition of nanorubber has negligible effect on the glass transition temperature of the epoxy. The difference in the dispersion ability of these two nanorubbers in epoxy is related to the difference in van der Waals forces between single nanoparticles, the chemical formula and the polarity of the systems. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41911.     

Nanostructured star‐shaped polythiophene with tannic acid core: Synthesis,characterization, and its physicochemical properties

For the first time, synthesis and characterization of a nanostructured star‐shaped polythiophene (PTh) with tannic acid core by both chemical and electrochemical oxidation polymerization methods through a “core‐first” method is reported. The chemical structures of all samples as representatives were characterized by means of Fourier transform infrared (FTIR), and ¹H nuclear magnetic resonance (NMR) spectroscopies. The electroactivity behaviors of the synthesized samples were verified under cyclic voltammetric conditions, and their conductivities were determined using the four‐probe technique. The synthesized star‐shaped PTh showed higher electrical conductivity and electroactivity than those of the PTh in both chemical and electrochemical polymerized samples, due to its large surface area, spherical, and three‐dimensional structure. Moreover, the thermal behaviors, optical properties, and morphologies of the synthesized samples were investigated by means of thermogravimetric analysis (TGA), ultraviolet–visible (UV–Vis) spectroscopy, and field emission scanning electron microscopy (FE‐SEM), respectively. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43513.     

Multifunctional polyaniline–tin oxide (PANI–SnO2) nanocomposite: Synthesis,electrochemical, and field emission investigations

Synthesis of PANI–SnO₂ nanocomposite has been performed using a simple two step chemical oxidative polymerization route. The structural, morphological and chemical properties of the as‐synthesized PANI–SnO₂ nanocomposite have been revealed by various characterization techniques such as SEM, TEM, XRD, FTIR, and XPS. Interestingly the as‐synthesized PANI–SnO₂ nanocomposite exhibits supercapacitance value of 721 F g^?1 with energy density 64 Wh kg^?1, which is noticed to be higher than that of pristine SnO₂ and PANI nanostructures. Furthermore, the galvanostatic charge–discharge characteristics revealed pseudocapacitive nature of the PANI–SnO₂ nanocomposite. The estimated values of charge transfer resistance and series resistance estimated from the Nyquist plot are found to be lower. Along with the supercapacitive nature, PANI–SnO₂ nanocomposite showed promising field emission behavior. The threshold field, required to draw emission current density of 1 μA/cm², is observed to be 0.90 V/μm and emission current density of 1.2 mA/cm² has been drawn at applied field of ～2.6 V/μm. The emission current stability investigated at preset values of 0.02 and 0.1 mA/cm² is observed to be fairly stable over duration of more than 3 h. The enhanced supercapacitance values, as well as, the promising field emission characteristics are attributed to the synergic effect of SnO₂ nanoparticles and PANI nanotubes. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41401.     

Polyaniline self‐assembled with DTPA: Facilely tuned morphology and properties

The effects of pH profile and “soft template” during aniline chemical oxidative polymerization (COP) were investigated and evaluated simultaneously with diethylene triamine pentaacetic acid (DTPA) as a structural directing agent. Formation of PANI nanotubes and nanoparticles, smooth microspheres, and urchin‐like microspheres were illustrated by evaluating the pH profile during aniline COP while considering the “soft template” effects of DTPA. PANI nanosheets with two semicurled edges were found in the system producing nanotubes, which provides an evidence for the “curling mechanism” of PANI nanotube formation. With different pH profiles, chemical structures and aggregation structures of the as‐synthesized PANI micro/nanostructures are similar, whereas their conductivity, wettability, Cr (VI) adsorption, and electrochemical behaviors are distinct. The present study indicates that if properly conducted, pH profile adjustment is more effective than “soft template” to control the morphology and to optimize the performance of PANI micro/nanostructures. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42403.     

Electrical,thermal, and mechanical properties of silicone foam composites filled with carbon-based nanofillers

It is critical to develop a new method to prepare engineered carbon-based fillers for high-performance applications. In this article, the functional nanocarbon-based fillers (FG-M) composed of multiwalled carbon nanotubes (MWNTs) and graphene oxide (GO) was synthesized by a simple self-assembly reaction under the existence of triethoxyvinylsilane. Based on the FG-M fillers, the silicone foam composites (FG-M/SF) were prepared, and the electrical, thermal, and mechanical properties of the composites were studied. Results showed that the FG-M could effectively improve the electrical, thermal, and mechanical properties of the composites compared with the single-filler system (GO/SF and MWNTs/SF). Especially, the composites exhibited the best synergistic effect on electrically, thermal and mechanical enhancement while the ratio of MWNTs and GO was close to 1:1. Moreover, the effect of type and content of fillers on the rheological properties and density of the composites was also studied. The result showed that the FG-M/SF system has good thixotropic and foaming performance. The FG-M filler will have a good application prospect in the preparation of high-performance SF composites.     

Poly(vinyl alcohol) functionalization with aldehydes in organic solvents: Shining properties of poly(vinyl acetals)

Poly(vinyl alcohol) has been functionalized with aldehydes in tetrahydrofuran (THF) with a good control of the grafting. A wide library of poly(vinyl acetals) could be obtained in order to study some structure/property correlations. The influence of the aldehyde nature on the functionalization rates has been studied, in particular for optical properties by measurement of the shininess for further applications in the cosmetic field. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40677.     

Preparation and enhanced electrochemical properties of Ag/polypyrrole composites electrode materials

Ag/polypyrrole (PPy) composites were synthesized with different dispersants via interface polymerization method. The morphology of the composites was investigated by scanning electron microscopy and transmission electron microscopy, and the results showed that the dispersant had strong effect on the morphology of the obtained composites. The structure of the products was characterized by Fourier transform infrared spectroscopy, and X‐ray diffraction. The specific capacitance and impedence of Ag/PPy composites electrode was evaluated through charge/discharge measurements and electrochemical impedance spectroscopy, respectively. Electrochemical performances indicated that Ag/PPy composite electrode used polyvinyl alcohol as dispersant exhibited the highest specific capacitance of 635.5 F/g at a current density of 2.45 mA/g, which provided potential application as supercapacitor materials. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Syntheses and optical,electrochemical, and photovoltaic properties of polymers with 6-(2-thienyl)-4H-thieno[2,3-b]indole with a variety of electron-deficient units

Conjugated polymers were synthesized and used for polymer solar cells with new electron-rich units, 6-(2-thienyl)-4H-thieno[2,3-b]indole (2-TTI). 2-TTI was coupled with electron-pulling units, including benzothiadiazole and benzimidazole derivatives, to provide push–pull types of conjugated polymers (poly(8-(heptadecan-9-yl)-6-(thiophen-2-yl)-8H-thieno[2,3-b]indole)-alt-(2-methyl-5,6-bis(octyloxy)-4,7-di(thiophen-2-yl)-2-(trifluoromethyl)-2H-benzimidazole) (PTTIDOCF3), poly(8-(heptadecan-9-yl)-6-(thiophen-2-yl)-8H-thieno[2,3-b]indole)-alt-(5,6-bis(octyloxy)-4,7-di(thiophen-2-yl)-2,1,3-benzothiadiazole) (PTTIDOBT), poly(8-(heptadecan-9-yl)-6-(thiophen-2-yl)-8H-thieno[2,3-b]indole)-alt-(2,2-dimethyl-4,7-di(thiophen-2-yl)-2H-benzimidazole) (PTTIMBI), and poly(8-(heptadecan-9-yl)-6-(thiophen-2-yl)-8H-thieno[2,3-b]indole)-alt-(2,2-dimethyl-5,6-bis(octyloxy)-4,7-di(thiophen-2-yl)-2H-benzimidazole) (PTTIDOMBI)). The synthesized conjugated polymers provided deep highest occupied molecular orbital energy levels for higher open-circuit voltages (V_OC). The device composed of PTTIDOMBI and [6,6]-Phenyl C₇₁ butyric acid methyl ester PC₇₁BM (1:2) with chloronaphthalene additive showed a V_OC of 0.72 V, a short-circuit current (J_SC) of 9.16 mA/cm², and a fill factor of 0.43; this gave a power conversion efficiency (PCE) of 2.84%. The PTTIDOMBI provided better morphology for enhanced charge transport, and this led to the higher J_SC and PCE of the organic solar cells. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47624.     

Preparation and electrochemical properties of polyaniline/reduced graphene oxide composites

Polyaniline (PANI)/reduced graphene oxide (rGO) composites were synthesized by in situ oxidative polymerization of aniline on reduced graphene sheets. Fourier transform infrared spectroscopy, X‐ray diffraction, thermogravimetric analysis, transmission electron microscopy, and scanning electron microscopy were used to characterize the composites. The results indicated PANI/rGO composites were produced and contained covalent bonds between the functional groups of PANI and rGO. A uniform coating of PANI on the rGO sheets had a synergistic effect on the properties of the composites. The electrochemical properties of the PANI/rGO composites produced using different feed ratios of aniline to rGO were studied. The results showed that the composites exhibited a maximum specific capacitance of 797.5 F/g at 0.5 A/g and minimum charge transfer resistance of 0.98 Ω when the feed ratio of aniline to rGO was 2:1. These values were superior to those of pure PANI and rGO. The composites also displayed excellent cycling stability, with specific capacitance retention of 92.43% after 1000 cycles. These stable structural composites show promise for the development of new supercapacitor applications. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46103.     

Synthesis and electrochemical properties of graphene oxide/nanosulfur/polypyrrole ternary nanocomposite hydrogel for supercapacitors

A method for synthesizing Graphene oxide (GO)/nano‐sulfur/polypyrrole (PPy) ternary nanocomposite hydrogel is depicted. The higher surface area of GO, PPy porous structure and their excellent conductivity are utilized, and the GO hydrogel can be made easily. The products are characterized by field‐emission scanning electron microscopy (FESEM), X‐ray diffraction (XRD), Fourier transform infrared (FTIR) spectra, and electrochemical workstation. The results demonstrated that GO/nano‐S/PPy ternary nanocomposite hydrogel is successfully synthesized. The electrochemical properties are investigated by cyclic voltammetry, galvanostatic charge/discharge measurements, and cycling life in a three‐electrode system in 1M Li₂SO₄ electrolyte solution. The GO/nano‐S/PPy ternary nanocomposite hydrogel exhibit a high specific capacitance of 892.5 F g^?1 at scan rates of 5 mV s^?1 and the capacitance retain about 81.2% (594.8 F g^?1) of initial capacitance (732.5 F g^?1) after 500 cycles at a current density of 1 A g^?1. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40814.     

Aqueous,interfacial, and electrochemical polymerization pathways of aniline with thiophene: Nano size materials for supercapacitor

Aniline was mixed with thiophene and oxidized by ammonium persulfate in the presence of sulfuric acid via an aqueous polymerization pathway (PAT‐AP). Aqueous polymerization was also carried by sodium lauryl sulfate surfactant, and also by interfacial and electrochemical polymerization pathways. Polymers prepared were characterized by physical, spectral, and electrochemical methods. Nanofibers (30–60 nm diameter) was obtained in the case of aqueous polymerization pathway, whereas interfacial (40–60 nm) and electrochemical polymerization pathways show particulate (500–600 nm) morphology. Polymer samples were used as electrode materials in supercapacitor. Among the four different pathways, PAT‐AP nanofibers show higher capacitance of 614 F g^?1 at 1 mV s^?1. The values of specific capacitance, energy, and power densities of PAT‐AP were found to be 400 F g^?1, 20 W h kg^?1 and 1200 W kg^?1, respectively, at a current density of 2 A g^?1. The retention capacitance is 78% after completion of 1000 cycles. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42013.     

Furan–thiophene copolymers: Electrosynthesis and electrochemical behavior

The electrochemical copolymerization of furan and thiophene was performed at a constant electrode potential in a binary solvent system consisting of boron trifluoride/ethyl ether and an additional amount of ethyl ether (molar ratio = 1 : 2). The obtained homopolymers and copolymers were characterized with cyclic voltammetry and infrared spectroscopy. The influence of the applied electropolymerization potential and the monomer feed ratio of furan and thiophene on the copolymers was investigated. The furan–thiophene copolymers showed good stability of the redox activity in an acetonitrile‐based electrolyte solution. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008     

Influence of dynamic crosslinking on the morphology,crystallization, and dynamic mechanical properties of PA6,12/EVA blends

This study investigated the effect of dynamic crosslinking of polyamide 6,12 and random copolymers of ethylene and vinyl acetate blends (PA6,12/EVA) on the morphology, crystallinity, and dynamic mechanical properties. The crosslinking agent was dicumyl peroxide (DCP), and the blends were processed in a torque rheometer. The morphology depended on the DCP content, and all blends exhibited the same crystallinity index. However, with increasing crosslinking degree, the interfacial tackiness (E) values increased from 1.8 to 2.7 nm. The lamellar structures of all blends started forming at approximately 160 °C, close to the temperature of pure polyamide. The crosslinked phase enhanced the pseudo‐elastic behavior of the blends and increased their molecular mobility activation energy. Samples with higher crosslinking degree exhibited smaller permanent deformation (0.01%) than those with low crosslinking. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44206.