Single-walled carbon nanotubes and their composites with polyaniline. Structure, catalytic and capacitive properties as applied to fuel cells and supercapacitors

The structure and hydrophilic–hydrophobic properties of SWCNTs before and after oxidative functionalization were studied by standard porosimetry method. The correlation between the values of specific surface of hydrophilic and hydrophobic pores for the two types of SWCNTs is discussed. The capacity properties of SWCNTs and their composites with polyaniline were also investigated. The composite layer is shown to have exceptionally high capacitance that is due to the large surface area of the former, as well as to the proceeding of the reversible faradaic reaction of counter ions intercalation into PANI. The structure and electrocatalytic properties of platinum metals incorporated by various methods into support of SWCNTs and their composites with PANI were studied. Kinetics of the reactions proceeding in DMFC and the mechanism of catalytic influence of the support are discussed. The structure of the catalytic layer is shown to be the main factor that determines the overall catalytic activity.     

Mechanism of formation of polyaniline flakes with high degree of crystallization using a soft template in the presence of cetyltrimethy‐lammonium bromide

Flake‐like polyaniline with various thicknesses was prepared by cationic emulsion polymerization of aniline monomer in the presence of cetyltrimethylammonium bromide (CTAB). The morphology of polyaniline with uniform and smooth flake‐like structure was observed using field‐emission scanning electron microscopy and transmission electron microscopy. The lamellar complex of (CTA)₂S₂O₈, acting as a reactive soft template for the formation of polyaniline, was investigated using low‐angle X‐ray diffraction. The soft template provides an expanding space for the growth of polyaniline, in which the oxidization of aniline monomers can construct effectively a flake‐like structure. The concentration of CTAB plays an important role in adjusting the d‐spacing of the soft template. Crystallization and composition of polyaniline were characterized using X‐ray diffraction and Fourier transform infrared spectroscopy. The X‐ray diffraction pattern has a sharp peak at 2θ = 6.4° (d‐spacing = 13.7 Å), showing that polyaniline has a solid‐state ordering structure and high degree of crystallization. Doping and dispersive experiments were also included in the study. Copyright © 2012 Society of Chemical Industry     

Optical,electrical and morphological properties of transparent binary doped polyaniline thin films synthesized by in situ chemical bath deposition

The development of polymeric thin films has attracted attention in the optoelectronics field due to their transparency. The aim of the research presented was to obtain transparent polyaniline thin films by easy in situ oxidative polymerization of aniline with ammonium persulfate in the presence of a binary doping agent–poly(vinyl alcohol) mixture. Poly(acrylic acid), 2‐acrylamido‐2‐methyl‐1‐propanesulfonic acid or sodium dodecylsulfate were mixed with hydrochloric acid to form the binary doping agents. Polyaniline thin films were produced during aniline polymerization on Corning glass slides immersed in the mixture in order to study their optical, electrical and morphological properties. The optical absorption coefficient and the energy band gap were evaluated by optical transmission of the films in the UV‐visible spectral region. The optical absorption coefficient of all polyaniline films was of the order of 10⁴ cm^?1 with a maximum transmittance up to 80% at 550 nm. In order to investigate the effect of the mixture on the surface morphology and roughness of the films, atomic force microscopy was used. In general, surface roughness was reduced threefold by adding a mixture and optical transmission was increased by 20–30% without significantly affecting the absorption coefficient and the band gap of polyaniline. Islands and needle‐like structures on the film surfaces were obtained from various mixtures affecting the conductivity; for example, 0.17 S cm^?1 was obtained from needle‐like morphology, while 1.9 × 10^?4 S cm^?1 was obtained from island morphology. Raman spectroscopy studies confirmed the presence of poly(vinyl alcohol) in the thin films. Copyright © 2011 Society of Chemical Industry     

聚苯胺季铵盐的合成及其性能研究

以邻氨基苯甲酸为原料,与氯乙醇反应生成2-氨基苯甲酸氯乙酯,然后用三乙胺季铵化合成了苯胺季铵盐,并将其聚合,通过红外光谱、紫外-可见光谱、X-射线衍射、循环伏安法和热重分析等对其结构与性能进行了研究。     

煤大分子酸掺杂聚苯胺的机理研究

聚苯胺的酸掺杂一直都集中在小分子无机酸和长链或是带有芳环的小分子有机酸方面，又对反应过程的研究甚少．选择烟煤作为一种煤大分子酸掺杂剂对苯胺聚合过程中的酸度和温度变化进行跟踪，并运用FTIR分析产物的结构．结果表明，煤与聚苯胺间存在较强的物理化学作用，煤掺杂制备聚苯胺的聚合机理随煤含量的变化有所差异，并且聚苯胺的导电机制仍属于极化子机制．     

聚苯胺防腐涂料在金属防护中的应用

综述了近年来国内外聚苯胺在金属腐蚀防护领域的研究状况。介绍了聚苯胺防腐涂层的制备方法、防腐机理。提出了聚苯胺防腐涂料目前存在的问题和今后的研究方向。     

Polyaniline/FE3O4 magnetic nanocomposite prepared by ultrasonic irradiation

Ultrasonic irradiation is employed to assist the chemical oxidative polymerization of aniline in the presence of Fe₃O₄ nanoparticles in order to prepare a polyaniline (PANI)/Fe₃O₄ magnetic nanocomposite. In the chemical oxidative polymerization of aniline in the initially neutral medium, the optimum molar ratio of the oxidant ammonium persulfate to the monomer aniline is 2 : 1. The prepared PANI is in the emeraldine form and is doped by sulfate anions. Fe₃O₄ particles are encapsulated by PANI and dispersed well in PANI. Fe₃O₄ increases the doping level and decreases the crystallinity of PANI. The PANI/Fe₃O₄ nanocomposite possesses conductivity and magnetic properties. Increasing the Fe₃O₄ content increases the magnetization of the PANI/Fe₃O₄ composite but decreases its conductivity. © 2006 Wiley Periodicals Inc. J Appl Polym Sci 102: 2107–2111, 2006     

导电性塑料的研究进展

本文介绍了导电性塑料的发现、分类、品种、应用、研究重点和发展前景。对导电性高聚物的一般合成方法如链聚合法和分步聚合法、特殊的合成方法如光化学聚合进行了总结，并对共轭高聚物的导电机理作了简单的评述。     

苯胺在聚醋酸乙烯酯中的聚合研究

以过硫酸铵为氧化剂,十二烷基苯磺酸为掺杂剂,将苯胺在聚醋酸乙烯酯(PVAc)基质中进行原位氧化聚合,制备导电聚苯胺PAn/PVAc复合材料,采用溶液浇铸法制成可溶性导电复合膜,电导率达10-2s/cm。考察了反应条件对复合膜电导率的影响,并进行了环境稳定性测试,用红外光谱进行了复合膜的结构表征,用扫描电镜对复合膜的表面形态进行了观察。     

Dielectric behavior of PVDF/POMA blends that have a low doped POMA content

The real (ε′) and imaginary (ε″) components of the complex permittivity of blends of PVDF [poly(vinylidene fluoride)] with POMA [poly(o‐methoxyaniline)] doped with toluenosulfonic acid (TSA) containing 1, 2.5, and 5 wt % POMA–TSA were determined in the frequency interval between 10² and 3 × 10⁶ Hz and in the temperature range from ?120 up to 120°C. It was observed that the values of ε′ and ε″ had a greater increase with the POMA–TSA content and with a temperature in the region of frequencies below 10 kHz. This effect decreased with frequency and it was attributed to interfacial polarization. This polarization was caused by the blend heterogeneity, formed by conductive POMA–TSA agglomerates dispersed in an insulating matrix of PVDF. The equation of Maxwell–Garnett, modified by Cohen, was used to evaluate the permittivity and conductivity behavior of POMA–TSA in the blends. A strong decrease was observed in POMA–TSA conductivity in the blend, which was bigger the lower the POMA–TSA content in the blend. This decrease could have been caused either by the POMA dedoping during the blend preparation process or by its dispersion into the insulating matrix. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 752–758, 2003