Synthesis, characterization and electrical properties of poly[bis-(2-aminophenyl)disulfide] and poly[bis(2-aminophenyl)diselenide]

Polybis(2-aminophenyl)diselenide and polybis(2-aminophenyl)disulfide were c hemically synthesized by oxidation of the monomers with ammonium persulphat e in 0.5 M H2SO4 and 1 M HCl media, at variable polymerization times. Synth esis of polybis(2-aminophenyl)diselenide for 4.5 h afforded a product with the spectroscopic properties (FT-IR and UV-Vis) similar to those of poly em eraldine. On the other hand, the synthesis of polybis(2-aminophenyl)disulfi de with these spectroscopic properties was not so straight forward and, con sequently, conditions such as medium, oxidizing agent, temperature, concent ration of monomer and oxidizing agent, and polymerization time had to be th roughly surveyed. Both emeraldine dichalcogenide polymers proved to be inso luble in common organic solvents, but they dissolve well in concentrated su lphuric acid, yielding blue solutions and PANI-like spectra. They get doped by iodine vapor, but very little doping is obtained in acid aqueous media. Their conductivities attained those of semiconduction. (C) 1999 Elsevier S cience S.A. All rights reserved.