Investigation of electrical property criterions of radiation resistance of the polymer films

The change of electrical properties must be a necessary criterion for the materials in radiation circumstances, especially for the polymer dielectric films used in the power and electronic devices. This paper studies the electrical property variation of polyimide films irradiated by γ-ray. It is found that both the volume resistivity and ac breakdown strength increase with the dose at the beginning of irradiation, and than decrease when the absorbed dose exceeds 3×10 ^{Gy. The authors propose that the volume resistivity and ac breakdown strength may be the indestructive and destructive electrical property criterions of radiation resistance for polymeric dielectrics respectively}