The conduction current characteristics of both original and corona-resistant polyimide films

The field dependent conduction current of both Dupont original and corona-resistant polyimide films before and after corona aging and at different temperatures are measured respectively. The conduction current of corona-resistant polyimide film is larger by about one order of magnitude than that of original one. The electric degradation thresholds before and after corona aging are also larger in the former, and decrease with the increasing of corona electric field. With the increasing of temperature, the electric degradation threshold increases for original polyimide film and decreases for corona-resistant polyimide film, in the meanwhile the conduction current increases and the trap energy level 0.9eV and 0.7eV can be derived from Arrehnius plot respectively.