A new way of synthesis nanohybrid cation‐exchanger applicable for membrane electrode

A novel polymeric composite namely, PANI‐PW/Ag (silver doped polyaniline phosphotungstate) was expediently obtained by sol‐gel method. PANI‐PW/Ag was characterized by Fourier transform infrared spectroscopy, X‐ray powder diffraction, UV–vis spectrophotometry, scanning electron microscopy, and thermogravimertic analysis. On the basis of ion exchange capacity and distribution studies, PANI‐PW/Ag, highly selective and sensitive to Cu(II), was used for the preparation of ion selective membrane for Cu(II). The electrode exhibits good potentiometric response for Cu(II) over a wide concentration range (1.0 × 10⁻¹−5.0 × 10⁻⁶ mol) with Nernstian slope of 27.8 mV per decade. Response time of the electrode is 9 s and it could be used for a period of 3 month and exhibits good selectivity toward Cu²⁺ in comparison to alkali, alkaline earth, transition, and heavy metal ions, with no interference caused by other heavy metals. POLYM. COMPOS., 35:1436–1443, 2014. © 2013 Society of Plastics Engineers     

Reversed micelle Synthesis of Ag/polyaniline nanocomposites via an in situ ultraviolet photo‐redox mechanism

Silver/polyaniline nanocomposites were synthesized in reversed micellar solution, and the reaction was performed via in situ reduction of silver nitrate in aniline by photolysis. The nanocomposites were characterized by ultraviolet‐visible spectroscopy, Fourier transform infrared spectroscopy, X‐ray diffraction, scanning electron microscopy, transmission electron microscopy, thermo‐gravimetric analysis, differential scanning calorimetric analysis, and electrochemical methods. The results showed that the Ag/polyaniline nanocomposites are composed of nano‐sized particles of 15–30 nm that contain Ag domains of 10–15 nm. The electrical conductivity of an Ag/polyaniline pellet is 95.89 S cm⁻¹, whereas a polyaniline pellet is found to be 3.1 × 10⁻² S cm⁻¹. Ag/polyaniline composites also have a higher degradation temperature and specific capacitance, when compared with pure polyaniline. Potentiodynamic polarization showed the anodic shifting of the zero current potential and a lower exchange current density for the Ag/polyaniline composite. Compared with polyaniline, the Ag/polyaniline nanocomposite is a promising candidate for coatings with improved anticorrosion performance. POLYM. COMPOS.,, 2012. © 2012 Society of Plastics Engineers     

Polyaniline/silver nanocomposites synthesized via UV–Vis‐assisted aniline polymerization with a reversed micellar microemulsion system

Polyaniline (PANI)/silver (Ag) nanocomposites were successfully synthesized within a sodium dodecyl sulfate reverse micro‐emulsion system and characterized by Fourier transform infrared spectroscopy, X‐ray diffraction, ultraviolet spectrometry, thermogravimetric analysis, scanning electron microscopy, transmission electron microscopy, and electrochemical methods. The results show that the core‐shell nanoparticles of less than 100 nm may be synthesized with PANI as shell formed around a core of nanoparticle. PANI/Ag nanocomposite prepared by this method has better thermal stability, higher conductivity, and electrochemical performance. The maximum conductivity (95.5 S/cm) was obtained when W₀ (water‐oil ratio) is 22. Cyclic voltammograms results show that PANI/Ag prepared by this method has a high response current and large capacitance. Polarization results show that E_corr (174.1 mV) and I_corr (50.6 μA/cm²) are better than the results for PANI and for PANI/Ag prepared by micro‐emulsion method. PANI/Ag nanocomposites prepared by the current method have potential applications in electrode materials, capacitors, conductive adhesives, and anticorrosion materials. POLYM. COMPOS. 37:1064–1071, 2016. © 2014 Society of Plastics Engineers     

The preparation,characterization, and properties of silver nanoparticle reinforced reduced graphene oxide–poly(amidoamine) nanocomposites

A simple approach was employed to synthesize silver nanoparticle (Ag NP) reinforced reduced graphene oxide–poly(amidoamine) (Ag‐r‐RGO–PAMAM) nanocomposites. The structural changes of the nanocomposites with the PAMAM and Ag NPs were confirmed by Fourier transform infrared spectroscopy, X‐ray photoelectron spectroscopy, X‐ray diffraction, Raman spectroscopy, and scanning electron microscopy. In addition, the performance was characterized with thermogravimetric and electrical conductivity instruments. The results indicate that the Ag NPs are well dispersed in fine size on the surface of the RGO–PAMAM composites, which results in an increase of at least 38% in thermostability and a certain enhancement in electrical conductivity. It is worth noting that the electrical conductivity of the nanocomposites was approximately 5.88 S cm^?1, which was higher than that of RGO–PAMAM, and increases with the rising content of silver nanoparticles. Meanwhile, the Ag‐r‐RGO–PAMAM nanocomposites still maintain a favorable dispersion in organic solvents. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 45172.     

Preparation,structural, and electrical studies of polyaniline/ZnFe2O4 nanocomposites

Polyaniline/ZnFe₂O₄ nanocomposites were synthesized by a simple and inexpensive one‐step in situ polymerization method in the presence of ZnFe₂O₄ nanoparticles. The structural, morphological, and electrical properties of the samples were characterized by wide angle X‐ray diffraction (WAXD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). WAXD and SEM revealed the formation of polyaniline/ZnFe₂O₄ nanocomposites. Infrared spectroscopy indicated that there was some interaction between the ZnFe₂O₄ nanoparticles and polyaniline. The dc electrical conductivity measurements were carried in the temperature range of 80 to 300 K. With increase in the doping concentration of ZnFe₂O₄, the conductivity of the nanocomposites found to be decreasing from 5.15 to 0.92 Scm⁻¹ and the temperature dependent resistivity follows ln ρ(T) ∼ T^−1/2 behavior. The nanocomposites (80 wt % of ZnFe₂O₄) show a more negative magnetoresistance compared with that of pure polyaniline (PANI). These results suggest that the interaction between the polymer matrix PANI and zinc nanoparticles take place in these nanocomposites. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Effect of conductive polyaniline in thermoplastic natural rubber blends on the mechanical,thermal stability,and electrical conductivity properties

This research was conducted to fabricate thermoplastic natural rubber/polyaniline (TPNR/PANI) blends via melt blending method using an internal mixer and followed by compression molding. The effects of PANI contents between 1 and 5 wt % PANI in the TPNR blends on the mechanical properties, thermal stability, electrical conductivity (impedance), and morphology observation were investigated. The TPNR/3 wt % PANI sample exhibited the highest tensile strength (3.7 MPa), elongation at break (583%), flexural strength (1.8 MPa), flexural modulus (37.0 MPa), and impact strength (7.1 kJ m⁻²). From the aspect of thermal properties, it was found that with the addition of PANI, the thermal stability of the TPNR/PANI increased. Comparing to nonconductive TPNR sample, the incorporation of PANI promoted the electrical conductivity characteristic to PANI-filled TPNR blends which showing a magnitude order of 10⁻⁹ S cm⁻¹. Scanning electron microscopy micrograph revealed the good distribution of PANI at the optimum content (3 wt % PANI) in the TPNR blends and the good interaction between TPNR and PANI. It can be concluded that the TPNR blends incorporated with a low loading of PANI could be a newly good conductive material. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47527.     

Preparation and properties of polyaniline/viscose fiber adducts

Polyaniline (PANI)/viscose fiber (VF) adducts were prepared by the polymerization of aniline with ammonium persulfate as an oxidant and VF as a template in hydrochloride solution. PANI deposited on the surface of VF because of the interaction between PANI and VF. The effect of PANI content and the reaction time on the performance of PANI/VF adducts were evaluated, respectively. The electrical conductivity of PANI/VF adducts increased with reaction time from 2 to 8 h, but the conductivity decreased at the higher reaction time because of the aggregation of PANI particles. With the increasing of reaction time, the tensile strength initially decreased to 1.299 cN/dtex at 3 h, subsequently increased to 1.528 cN/dtex at 8 h, and finally diminished a little to 1.475 cN/dtex at 24 h. When the adducts were washed in water, the conductivity only decreased from 2.71 × 10⁻³ to 2.4 × 10⁻³ S/cm, and it was stable after washing 50 times. POLYM. COMPOS., 38:782–788, 2017. © 2015 Society of Plastics Engineers     

Flame synthesis of mixed tin‐silver‐copper nanopowders and conductive coatings

The single‐step direct synthesis of tin‐silver‐copper nanopowders and nanostructured coatings using the flame‐based high‐temperature reducing jet (HTRJ) process is reported. Nanostructured coatings were deposited and sintered within the HTRJ reactor to study the effect of reductive sintering temperature on their electrical conductivity and surface morphology. Although the ultimate application of these nanoparticles is in printed electronics, which requires dispersing them as stable inks before depositing and sintering them, our approach of direct deposition from the gas phase provides an upper limit on the conductivity achievable with a given composition. The directly deposited coatings had high electrical conductivity, including a value of 2 × 10⁶ S/m for 36 wt % Cu‐40 wt % Ag‐24 wt % Sn sintered at 200°C. This is twice the conductivity of a pure silver coating prepared under similar conditions. Moreover, similarly high electrical conductivity was achieved using only 20% Ag with sintering at 300°C. © 2015 American Institute of Chemical Engineers AIChE J, 62: 408–414, 2016     

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     

Studies on Fourier transform infrared spectroscopy,scanning electron microscope,and direct current conductivity of polyaniline doped zinc ferrite

In situ polymerization of aniline was carried out in the presence of zinc ferrite to synthesize polyaniline/ZnFe₂O₄ composites (PANI/ZnFe₂O₄) by chemical oxidation method. The composites have been synthesized with various compositions (10, 20, 30, 40, and 50 wt %) of zinc ferrite in PANI. From the Fourier transform infrared spectroscopy (FTIR) studies on polyaniline/ZnFe₂O₄ composites, the peak at 1140 cm⁻¹ is considered to be measure of the degree of electron delocalization. The surface morphology of these composites was studied with scanning electron micrograph (SEM). The dc conductivity has been studied in the temperature range from 40–160°C and supports the one‐dimensional variable range hopping (1DVRH) model proposed by Mott. The results obtained for these composites are of scientific and technological interest. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Molecular composites obtained by polyaniline synthesis in the presence of p‐octasulfonated calixarene macrocycle

Polyaniline (PANI) molecular composites were synthesized by chemical oxidative polymerization of the aniline and aniline dimer, N‐phenyl‐1,4‐phenylendiamine, in the presence of a macrocycle, calix[8]arene p‐octasulfonic acid (C8S), using ammonium peroxidisulfate as oxidant. The macrocycle has acted both as acid dopant and surfactant to obtain processable PANI‐ES. The PANI/calix[8]arene p‐octasulfonic acid composite was also obtained by a simple doping of PANI emeraldine base form with calix[8]arene sulfonic acid. The structure of materials was confirmed by Fourier transform infrared, UV–vis and nuclear magnetic resonance spectroscopy. All synthesized composite materials are amorphous and soluble in chloroform, dimethylsulfoxide, NMP, showing excellent solution‐processing properties combined with electrical conductivity. Cyclic voltammetry evidenced a good electroactivity for the composite films. Dielectric properties (dielectric constant and dielectric losses) were determined and are comparable with those of other PANI/ionic acid polymer composites. Preliminary studies have evidenced a high dielectric constant (10⁴ at 100 Hz) and electrical conductivity of 6 × 10^?3 S/cm for PANI composites. From sulfur elemental analysis of the PANI/calixarene, it results that the content in macrocycle is ～30% (weight). © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Enhanced conductivity and fluorescence of polyaniline doped with Eu3+, Tb3+, and Y3+ ions

The doped polyaniline (PANI) with rare earth ions, which exhibits an increasing conductivity and strongly enhanced fluorescence emission, was prepared by dispersing PANI powder suspension in acetonitrile solution containing rare earth ions according to different mass ratios of rare earth ions to PANI at room temperature. The structure of the doped PANI was characterized by the spectra of FTIR, Raman, UV-vis, and XRD. Red-shifted change for the quinoid and benzenoid stretching vibration is observed in IR and Raman spectra after doping rare earth cations, and UV-vis absorption peak also presents a red-shift, indicating that the doped PANI possesses a better delocalization of electrons along the mainchain backbone. The experimental data show that the electrical and optical behaviors of PANI strongly depend on the species of rare earth cations and their concentration. It is found that enhancing fluorescence for the doped PANI is observed by comparing with emeraldine base (EB). Moreover, the conductivity of the protonated PANI samples doped with Eu³⁺, Tb³⁺, and Y³⁺ ions, increases from 2.1 × 10⁻⁴ to 3.33 S cm⁻¹, 1.50 × 10⁻¹ S cm⁻¹ and 2.26 × 10⁻¹ S cm⁻¹. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

One‐step synthesis of polyaniline nanofibers decorated with silver

Polyaniline (PANI)/silver (Ag) nanocomposites containing PANI nanofibers decorated with well‐dispersed Ag nanoparticles were obtained with interfacial polymerization. It was interesting that silver nitride affected not only the diameter and crystallinity of the PANI nanofibers but also their room‐temperature conductivity. The conductivity increased with increasing Ag loading up to 10 (molar ratio of aniline to silver nitride), but the conductivity moderately decreased with further increasing Ag loading. Scanning electron microscopy and X‐ray diffraction analysis results indicate that the diameter of the PANI nanofibers became smaller and smaller, and their crystallinity got better and better with increasing Ag loading. However, Fourier transform infrared analysis proved that the balance of oxidized and reduced units of PANI became big with increasing Ag loading, which may have resulted in the decreasing conductivity of PANI. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Synthesis,characterization, and comparison of self‐doped,doped, and undoped forms of polyaniline,poly(o‐anisidine), and poly[aniline‐co‐(o‐anisidine)]

Polyaniline (PANI), poly(o‐anisidine), and poly[aniline‐co‐(o‐anisidine)] were synthesized by chemical oxidative polymerization with ammonium persulfate as an oxidizing reagent in an HCl medium. The viscosities, electrical conductivity, and crystallinity of the resulting polymers (self‐doped forms) were compared with those of the doped and undoped forms. The self‐doped, doped, and undoped forms of these polymers were characterized with infrared spectroscopy, ultraviolet–visible spectroscopy, and a four‐point‐probe conductivity method. X‐ray diffraction characterization revealed the crystalline nature of the polymers. The observed decrease in the conductivity of the copolymer and poly(o‐anisidine) with respect to PANI was attributed to the incorporation of the methoxy moieties into the PANI chain. The homopolymers attained conductivity in the range of 3.97 × 10^?3 to 7.8 S/cm after doping with HCl. The conductivity of the undoped forms of the poly[aniline‐co‐(o‐anisidine)] and poly(o‐anisidine) was observed to be lower than 10^?5 J/S cm^?1. The conductivity of the studied polymer forms decreased by the doping process in the following order: self‐doped → doped → undoped. The conductivity of the studied polymers decreased by the monomer species in the following order: PANI → poly[aniline‐co‐(o‐anisidine)] → poly(o‐anisidine). All the polymer samples were largely amorphous, but with the attachment of the pendant groups of anisidine to the polymer system, the crystallinity region increased. The undoped form of poly[aniline‐co‐(o‐anisidine)] had good solubility in common organic solvents, whereas doped poly[aniline‐co‐(o‐anisidine)] was moderately crystalline and exhibited higher conductivity than the anisidine homopolymer. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci, 2006     

Optical,electrical, and electrochemical properties of graphene based water soluble polyaniline composites

Polyaniline (PANI) is one of the most common polymers known for its conducting properties. However, poor water solubility limits its applications. In this work, PANI has been functionalized with sulfonic acid groups to produce sulfonated PANI (SPANI) offering excellent solubility in water. To compensate for the decrease of electrical conductivity due to functionalization, SPANI was combined with reduced graphene oxide (RGO) to form SPANI/RGO composites with interesting optical, thermal, and electrical properties. The composites have been characterized using X‐ray diffraction (XRD), field emission scanning electron microscopy, UV–vis absorption spectroscopy, Raman spectroscopy, Fourier‐transform infrared spectroscopy, X‐ray photoelectron spectroscopy, thermogravimetric analysis, cyclic voltammetry, and four probe electrical conductivity measurement. The SPANI/RGO composites show increased thermal stability, reduced optical band gap and improved electrochemical properties compared with the pure polymer. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42766.     

Development of whey protein isolate/polyaniline smart packaging: Morphological,structural, thermal,and electrical properties

Development of smart packaging from biodegradable polymers that allow monitoring food exposure conditions is important to reduce food and material packaging waste. The objective of this article is to evaluate the conductivity of polyaniline (PANI) in its doped form with dodecylbenzene sulfonic acid on morphological, structure, thermal, and electrical (Hall effect) properties of whey protein isolate (films. Films show immiscible with 10⁻³ S cm⁻¹ conductivity and semiconductor behavior due to a phase separation that is observed (scanning electron microscopy and thermogravimetric analysis). Fourier transform infrared and Raman spectra do not present changes in relation to control samples, suggesting no chemical interaction with polymers. This result is probably due to deprotonation of PANI. No significant differences are observed for conductivity of film made above 60 mg mL⁻¹ of PANI. Films showed semiconducting properties that allow a new application on smart packaging to help monitor electrical properties of foods in processes of degradable. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47316.     

Synthesis of nano‐sized ZnO and polyaniline‐zinc oxide composite: Characterization,stability in terms of DC electrical conductivity retention and application in ammonia vapor detection

Nano‐sized particles of Zinc oxide (ZnO) were synthesized using a new chemical rout. The chemical oxidative polymerization of aniline in the presence of nano ZnO was employed to synthesize a polyaniline‐zinc oxide (PANI‐ZnO) nanocomposite. The material was characterized by using transmission electron microscopy, XRD, scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FTIR), and Thermogravimetric analysis (TGA). The conductivity measurements showed the resulting composites possessed higher conductivity as compared to pure polyaniline (PANI). The nanocomposite exhibited fairly sensitive towards solution of aqueous ammonia (NH₃), when it was exposed to various concentrations of NH₃ in an ambient room temperature. The results show that the sensor has good sensitivity and good repeatability upon repeated exposure to NH₃. PANI‐ZnO nanocomposite was also used to study electrical conductivity under isothermal conditions in the temperature range 50–130°C. The composite was found stable under ambient conditions below 90°C in terms of DC electrical conductivity retention. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Double regulation of conductivity by adhesive hydrogel based on catechol-modified sodium alginate /acrylamide hydrogel with silver ions

The purpose of this study is to explore how to control the conductivity of gel conveniently and effectively through experiments. First, a kind of acrylamide-based composite with adhesion and conductivity adjustment was prepared by adding silver ions and silver monomers to the gel in one step. The semi interpenetrating network structure formed by the molecular chain of polyacrylamide and catechol modified sodium alginate in the composite is cross-connected with silver ions to form a double network structure. This change of network structure not only makes the structure of gel more stable, but also brings extraordinary conductivity. Secondly, different types of conductive ions and organic solutions were added to the gel system. Electrochemical impedance spectroscopy showed that the addition of silver enhanced the conductivity of the material; When NaNO₃ is used to replace water molecules in PAM, the ionic conductivity can be increased by 75.3% (from 2.44 × 10⁻⁵ to 20.8 × 10⁻⁵ mscm⁻¹). When PDA/PAM was soaked in AgNO₃, the ionic conductivity increased in the range of 10.4% ~ 674%. It provides a novel strategy for controlling the conductivity of composite materials.     

Ferromagnetic polyaniline/TiO2 nanocomposites

Novel ferromagnetic semiconducting polyaniline PANI/TiO₂ nanocomposites were synthesized by the oxidative polymerization of aniline with ammonium peroxydisulfate in an aqueous medium, in the presence of colloidal TiO₂ nanoparticles (d ∼ 4.5 nm), without added acid. The morphological, magnetic, structural, and optical properties of the PANI/TiO₂ nanocomposites prepared at initial aniline/TiO₂ mole ratios 80, 40, and 20 were studied by scanning electron microscopy, superconducting quantum interference device, X‐ray powder diffraction, FTIR, Raman, and UV‐Vis spectroscopies. The emeraldine salt form of linear PANI chains as well as the presence of phenazine units, branched PANI chains, and anatase crystalline structure of TiO₂ in PANI/TiO₂ nanocomposites was confirmed by FTIR and Raman spectroscopies. The electrical conductivity of synthesized composites was ∼10⁻³ S cm⁻¹. The room temperature ferromagnetic response with coercive field of H_c ∼ 300 Oe and the remanent magnetization of M_r ∼ 4.35 × 10⁻⁴ emu/g was detected in all investigated PANI/TiO₂ nanocomposites. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers     

Polyaniline/Ag nanocomposite synthesized by using aniline as dispersant and stabilizer of nanosilver sol

Polyaniline/silver (PANI/Ag) nanocomposite was successfully prepared by in‐situ polymerization from nanosilver sol using aniline (An) as both dispersant and stabilizer and characterized by FT‐IR, XRD SEM, TEM and electrochemical methods, respectively. The results showed that core‐shelled composite particles of less than 100 nm were synthesized with PANI as shell formed around a core of silver nanoparticles at higher aniline levels. Compared to pure PANI, PANI/Ag nanocomposites have higher electrical conductivity (65.98 S/cm) and current response and capacitance as well. Potentio dynamic polarization showed the anodic shifting of zero current potential and a lower exchange current density for the PANI/Ag composite. Compared with PANI, the PANI/Ag nanocomposite is a promising candidate for coatings with improved anti‐corrosion performance. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013