Charge storage characteristics in hybrid electret film consisting of porous PTFE and PP with negative corona charging
电晕充电多孔PTFE/PP复合驻极体过滤材料的电荷存储特性

The charge storage characteristics of hybrid electret film consisting of porous PTFE and PP, which come from Shanghai Dagong New Materials Co. Ltd., are investigated by means of corona charging, open-circuit thermally stimulating discharge (TSD ) analysis and isothermal surface-potential measurement. The results indicate that there are space charge and polar charge for the hybrid film charged by means of corona discharge method, and the interface between PP and PTFE layers are the main source of charge traps. When charging is carried out through different sides, the difference of TSD current spectra is very large. The electric field generated by space charge can cause polarization of polymer and give rise to polar charge, which exists as compensative charge of space charge, so that the surface potential measurement can't reveal the charge characteristics inside hybrid films.