SYNTHESIS AND CHARACTERIZATION OF POLYAZOMETHINE CONDUCTING POLYMERS AND OLIGOMERS

Conjugated polyazomethine polymers were prepared from the polycondensa tion of terephthalaldehyde with 4,4'-thiodianiline, and 4,4-thiodibenz aldehyde with 4,4'-thiodianiline, 4,4'-phenylenediamine and benzidine. The polymers showed good stability in air and were soluble in many or ganic solvents. The electrical conductivities of the undoped and doped (H2SO4 and I-2) polymers were studied. Doping the polymers markedly i ncreased their conductivities from 10(-8)-10(-11) S cm(-1) (dielectric region) to 10(-3)-10(-5) S cm(-1) (semiconducting region). The polyme rs were characterized by IR spectroscopy, elemental analyses, viscosit y measurements and X-ray diffraction. Furthermore, polyazomethine olig omers were prepared and a comparative study of the physical properties of the oligomers and their corresponding polymers was performed. The electrical behavior of the oligomers was studied. It was found that ol igomers with a minimum of eight aromatic (Ar) rings gave almost the sa me electrical conductivities as long-chain polymers.