Abstract
Mechanism of ac conduction in heat-treated poly (acrylonitrile) and poly (ethylene 2, 6-naphthalate) was studied in the temperature range of -96°C-170°C and in the frequency range of 120 Hz-100 kHz. The temperature and frequency dependences of ac conductivity at low temperatures were compared with Austin-Mott's equation for ac hopping conduction in amorphous materials, which shows fairly reasonable agreements. This fact indicates that at low temperatures electronic ac hopping conduction between localized states takes place in the polymers. At higher temperatures, however, the dc conduction mechanism can be explained in terms of thermally activated process. Dielectric properties due to the molecular motions of polymer chains are also discussed, since they affect ac conductivity.
