FREQUENCY-DEPENDENT CONDUCTIVITY AND DIELECTRIC PERMITTIVITY OF EMERALDINE BASE AND WEAKLY DOPED POLY(O-TOLUIDINE)

We report the results on the low frequency dielectric study of pressed pellets of poly(o-toluidine) (POT) in the emeraldine base and weakly doped emeraldine salt forms. The parameter describing the doping defin ed as y = [Cl-]/[N] was synthesized to be y = 0, y = 0.03 and y = 0.07 . We suggest that the presence of polarons and bipolarons is responsib le for the dielectric relaxation mechanism as well as the frequency an d temperature dependence of conductivity. A broadening in the spectrum of relaxation times of the dielectric relaxation process due to charg e motion via creation/annihilation of polarons and bipolarons, and the ir subsequent diffusion becomes faster as doping increases. (C) 1998 E lsevier Science S.A. All rights reserved.