Polyanilines optical

Solution-cast films of polyaniline optical quality transparent electrodes... 

Y Cao, GM Treacy, P Smith, and AJ Heeger, Solution-cast films of polyaniline optical-quality transparent electrodes, Appl. Phys. Lett., 60 2711-2713, 1992. 

Cao, Y., Treacy, G. M., Smith, R, and Heeger, A. J., Solution-cast films of polyaniline optical-quality transparent electrodes, Appl. Phys. Lett., 60, 2711-2713 (1992). Gustafsson, G., Cao, Y., Treacy, G. M., Klavetter, E, Colaneri, N., and Heeger, A. J., Flexible light-emitting diodes made from soluble conducting polymers. Nature, 357, 411-419 (1992). 

Y. Gao, G. M. Treacy, P. Smith, and A. J. Heeger. 1992. Solution-cast films of polyaniline Optical-quality transparent electrodes. Appl Phys Lett 60(22) 2711-2713. 

Boronic acid-containing polyaniline has also been utilized in diabetes-related research. One such polymer (23) (Fig. 17) has been observed to exhibit a linear near-infrared optical response to saccharides.43 The polymer was prepared by the copolymerization of aniline with 3-aminophenylboronic acid using lOmM (NH4)S208 in 1M HC1. The films were observed to undergo changes in the absorption spectra on addition of saccharides at pH 7.2. 

Z. Ge et al. 1993 Fiber optic evancescent wave sensor using polyaniline... 

Importantly, deep oxidation of polyaniline leads to a material that becomes insulating and spinless. This phenomenon was demonstrated in case of poly(fV-methylaniline) by monitoring ESR signal and electric conductivity of the sample (Wei et al. 2007). Deep oxidation results in the formation of the so-called polaron pairs that are evidenced by optical spectra. Because the hopping probability of two polarons on a single chain is too small, polaron pairs do not contribute to electric conductivity and ESR signal. 

As a conducting polymer, polyaniline has many electronics-related applications, such as rechargeable batteries (Tsutsumi et al. 1995), multilayer heterostructure light-emitting diode devices (Onoda Yoshino 1995), biosensors (Bartlett Whitaker 1987), elec-trochromic windows (Nguyen Dao 1989), and nonlinear optical materials (Papacostadi-nou Theophilou 1991). Polyaniline may be prepared from aniline by both electrochemi-... 

Aizawa presented an overview on the principles and applications of the electrochemical and optical biosensors [61]. The current development in the biocatalytic and bioaffinity bensensor and the applications of these sensors were given. The optical enzyme sensor for acetylcholine was based on use of an optical pH fiber with thin polyaniline film. 

Optical quality thin films of metallic polymers are useful, therefore, as transparent electrodes [68]. For example, polyaniline [69], polypyrrole [70] and PEDOT [71] have been used as transparent hole-injecting electrodes in polymer LEDs (the initial demonstration of mechanically flexible polymer LEDs utilized PANl as the anode [69]). Transparent conducting films can be used for a variety of purposes for example, as antistatic coatings on CRT screens, as electrodes in liquid crystal display cells, or for fabricating electrochromic windows. 

Transparent conducting polymers are of interest [66]. A number of these doped conducting polymers have been prepared as thin conductive films. It was shown that the optical window for doped polyaniline and other polymers can be tuned through control of processing conditions [67]. 

This alternative approach has also been successfully employed to produce optically active polyanilines. The use of optically active dopant anions such as (H-) - or ( - ) - camphorsulfonate (CSA ) [37-39], (-i-)-or( —) - tartrate [40] and related chiral anions induces macroasymmetry in to the polyaniline chains. We [41] and others [42] have recently shown that films of optically active polyaniline salts such as PAn( -1- )-HCSA, or the optically active emeraldine base (EB) derived from them, exhibit chiral discrimination towards chiral chemicals such as the enantiomers of CSA and amino acids. 

Intercalation of electroactive polymers such as polyaniline and polypyrrole in mica-type layered silicates leads to metal-insulator nanocomposites. The conductivity of these nanocomposites in the form of films is highly anisotropic, with the in-plane conductivity 10 to 10 times higher than the conductivity in the direction perpendicular to the film. Conductive polymer/oxide bronze nanocomposites have been prepared by intercalating polythiophene in V2O5 layered phase, which is analogous to clays. °° Studies of these composites are expected not only to provide a fundamental understanding of the conduction mechanism in the polymers, but also to lead to diverse electrical and optical properties. 

A different approach was taken by Kumar and associates [61]. Fie also embedded metals in polymers, but used as his precursor the polymer and not the monomer. In his first study a composite material containing amorphous Cu nanoparticles and nanocrystalline CU2O embedded in polyanUine matrices was prepared by a sonochemical method. These composite materials were obtained from the soni-cation of copper (II) acetate when aniline or 1% v/v aniline-water was used as the solvent. Mechanisms for the formation of these products are proposed and discussed. The physical and thermal properties of the as-prepared composite materials are presented. A band gap of 2.61 eV is estimated from optical measurements for the as-prepared CU2O in polyaniline. 

Polyaniline (PANI) is one of the most important polymeric materials, owing to its electrical, optoelectrical and optical properties209. The preparation of polyaniline is very easy. Ammonium persulfate polymerizes monomeric aniline to PANI whose repeating moiety is described by 134. The polymer is stable and environment compatible. 

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