Polyaniline based materials

Soluble conducting polymers are very attractive materials in order to realize microwave absorbing materials. However, structural parameters of the polymer and details of preparation techniques have to be severely controlled in order to get reproducible and expected values. More specifically, DBSA doped polyaniline based materials are promising materials if two major problems are fixed homogeneity of properties after extrusion and stability over time. Work is in progress now in order to increase properties stability of the polymer. 

A second type of soHd ionic conductors based around polyether compounds such as poly(ethylene oxide) [25322-68-3] (PEO) has been discovered (24) and characterized. These materials foUow equations 23—31 as opposed to the electronically conducting polyacetylene [26571-64-2] and polyaniline type materials. The polyethers can complex and stabilize lithium ions in organic media. They also dissolve salts such as LiClO to produce conducting soHd solutions. The use of these materials in rechargeable lithium batteries has been proposed (25). 

Work with PPy and PAni has reached the industrial stage. Bridgestone-Seiko has been selling coin-shaped 3-V polyaniline-based batteries for 5 years (1987-1992), and polypyrrole-based batteries were developed by Varta/BASF in the same period. Such batteries have lower energy densities than those of conventional batteries, but they are superior in terms of selfdischarge. The main characteristics of a typical PAni battery are compared to those of lead and Cd-Ni batteries in Table 4. The values mentioned for energy density and electric capacity density refer to the active material alone. 

Title Use of Sulphonic, Phosphonic and Phosphoric Acids as Dopants for Polyaniline and for Conductive Polyaniline-Based Composite Materials... 

Inherently conductive polymers are also being used as coatings on other polymers, as well as on electronics themselves. One such material, produced by Ormecon Chemie GmbH Co. of Ammersbek, Germany, uses a dispersion of polyaniline. Another material, being developed by Bayer AG of Leverkusen, Germany, is based on polythiophene. A polythiophene coating for sheet and film applies the conductive polymer in a dispersion in polyurethane [2]. 

Yan, W, Feng,X., et al. A super highly sensitive glucose biosensor based on Au nanopar-ticles-AgCl polyaniline hybrid material. Biosensors and Bioelectronics,23(7), 925-931 (2008). 

Metal-Polyaniline Nanocomposites Based on Polyaniline Nanofibers Electrical Properties of Metal-Polyaniline Nanocomposite Materials Other Methods to Make Metal-Polyaniline Nanocomposites Growth of Inorganic Nanoparticles by In Situ Metathesis Reactions Unusual Photothermal Effect of the Polyaniline Nanofibers Flash Welding.7-30... 

Foster, M., private conversations, Physical Optics Corporation, Torrance, CA, 1995. Passiniemi, R, Laakso, J., Ruohonen, H., and Vakiparta, K., Electrically conducting polymer blends based on polyaniline, in Materials Research Society Symposium Proceedings on Electrical, Optical and Magnetic Properties of Organic Solid State Materials III, Vol. 413, 1996, p. 577. 

Onium salts such as triarylsulfonium and diaryliodon-ium salts are a class of materials that decompose upon exposure to ultraviolet radiation or to an e-beam to generate a protonic acid [56,57]. These salts are further discussed in Section II.D. Conductivity of 0.1 S/cm was attained when a polyaniline base film containing an onium salt was irradiated [54]. 

Figure 8.4 shows that the polyaniline that was synthesized is in fact polyaniline in its emeraldine base [27]. Additionally, all samples exhibit peaks around 1,306 cm , which is attributed to the jt-electron delocalization induced in the polymer by protonation. The peak around 1,375 cm is attributed to the C-N stretch in the base. The peak around 822 cm is due to C-H bond out of plane [28]. It can also be seen that the addition of tin oxide mainly caused a physical rather than a chemical reaction between the polyaniline and the tin oxide, as the FTIR spectrum is essentially unchanged. The addition of multiwall carbon nanotubes to the polyaniline matrix material also shows more of a physical mixing rather than a chemical mixing. This explains the results that are obtained in the hydrogen sorption measurements, to be discussed in the next section. The addition of aluminum to the sample, however, clearly shows a chemical reaction between the polyaniline and the aluminum powder. The large peak around 1,150 cm is a sign of increased conductivity and was described as the electron-like band [28]. 

Jurczyk MU, Kumar A et al (2007) Polyaniline-based nanocomposite materials for hydrogen storage. Int J Hydrogen Energy 32(8) 1010-1015... 

Electronically conducting polymers (ECPs) such as polyaniline (PANI), polypyrrole (PPy) and po 1 y(3.4-cthy 1 cncdi oxyth iophcnc) (PEDOT) have been applied in supercapacitors, due to their excellent electrochemical properties and lower cost than other ECPs. We demonstrated that multi-walled carbon nanotubes (CNTs) prepared by catalytic decomposition of acetylene in a solid solution are very effective conductivity additives in composite materials based on ECPs. In this paper, we show that a successful application of ECPs in supercapacitor technologies could be possible only in an asymmetric configuration, i.e. with electrodes of different nature. 

There is a large potential for conducting polymers as corrosion-inhibiting coatings. For instance, the corrosion protection ability of polyaniline is pH-dependent. At lower pH polyaniline-coated steel corrodes about 100 times more slowly than noncoated steel. By comparison, at a pH of about 7 the corrosion protection time is only twice for polyaniline-coated steel. Another area of application involves creation of solid state rechargeable batteries and electrochromic cells. Polyheterocycles have been cycled thousands of times with retention of over 50% of the electrochromic activity for some materials after 10,000 cycles. IR polarizers based on polyaniline have been shown to be as good as metal wire polarizers. 

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