Enhanced dielectric and energy storage properties of polypropylene by high‐energy electron beam irradiation
Jing Hu, Xuanchen Zhao, Junhao Xie, Yan Liu, Shulin Sun
Abstract
Abstract In this work, electron beam irradiation technology was used to increase the dielectric and energy storage performance of polypropylene (PP) films. Electron beam irradiation makes no difference on the crystal morphology but decreased the crystallinity and crystal size of PP. Besides, irradiation improved the thermal stability and polarity of PP. The irradiated PP films behaved much higher dielectric constant than pure PP films. Actually, the dielectric constant of the irradiated PP with 30 kGy was 3.98, while the dielectric constant of pristine PP was only 2.8. Furthermore, the irradiated PP films still kept low dielectric loss and AC conductivity. Weibull distribution test results proved electron beam irradiation improved the breakdown strength of PP films. The discharged energy storage of PP films increased from 1.3 J/cm 3 of pristine PP film to 3.6 J/cm 3 of irradiated PP with 30 kGy film. Moreover, the PP film irradiated with 30 kGy displayed an excellent charge–discharge efficiency of more than 95%. This research provides an easy and practical approach to investigate dielectric PP material for energy storage.