Abstract
Aniline hydrochloride was oxidized in the solid state with three different oxidants: ammonium peroxydisulfate, iron(III) chloride, and silver nitrate. Polyaniline salt was obtained after a few hours when ammonium peroxydisulfate was used as an oxidant.
The polymerization of aniline hydrochloride with silver nitrate leads to polyaniline only after several days; in the case of iron(III) chloride, aniline oligomers were obtained. The conductivity of the polyaniline was 0.21 S cmMINUS SIGN 1 when ammonium peroxydisulfate was applied; it is comparable with the conductivity of a 'standard' polyaniline.
The oxidation with silver nitrate yields a composite material, polyaniline salt and silver particles, with conductivity 1.5 x 10MINUS SIGN 3 S cmMINUS SIGN 1. Photoacoustic spectroscopy was employed to study the kinetics of the oxidation reaction.
Infrared and UV-vis spectra were efficient tools to characterize the final products, and to compare their molecular structure with that of the polyaniline prepared under 'standard' conditions in aqueous medium.