Effect of Electron-Beam Irradiation Modification on High-Temperature Dielectric Properties of Polypropylene Film for Capacitors

Under the high temperature environment, the breakdown strength of polypropylene ( PP ) used in metallized film capacitors is reduced, the loss is increased, the performance is seriously damaged, which is affect the service life of the capacitor. In this paper, a cross-linking modification method of polypropylene based on electron-beam (EB) irradiation is proposed to improve the insulation performance of PP film for metallized film capacitors at high temperature. The results show that compared with the original PP at 125 ℃, the breakdown strength of the modified film increased by 14.6 %, the conductivity decreased by 63.5 % , and the performance of the film could be improved. This method has guiding significance for improving the high temperature performance of PP.