The properties of alkoxy substituted polyaniline

Summary form only given. Cyclic voltammograms of methoxy, ethoxy and 2,5-dimethoxy substituted polyaniline in media of various pH show two redox waves between -0.2V to 0.8 V. A third wave appears between these two waves if the scanning potential is high or in medium of higher pH. According to the results of molecular weight determination by GPC, the third redox wave was attributed to the degradation products during hydrolysis. Epr and UV-visible spectra indicate the existence of radical in the potential range between the two redox waves. The higher the pH of the medium, The wider the potential range where the radical is stable. The larger the alkoxy group, the narrower the range where the radical is stable. The potential range where the radical is stable shifted to lower potential for 2,5-dimethoxy substituted polyaniline. Both monomer concentration and rate of synthesis affect the morphology of ethoxy-substituted polyaniline. Regular short fiber structure was formed under low current density when the monomer concentration is low. When monomer concentration is high, short regular fiber structure were always formed under high or low current densities. The regular short fiber structure was formed under slow growing rate.