Electret state in blendmers of polypropylene, PP grafted with maleic anhydride and polycarbonate

Electret properties in Blendmer of polypropylene, Maleic anhydride grafted [MAH-PP] and polycarbonate have been studied. The blendmer films were polarized by corona discharge or by applying various d.c. electric field. Temperature dependence of residual surface charge and thermally stimulated depolarization current [TSDC] in the blendmers were measured. The amount of surface charge increased with the increase of MAH-PP content. Two peaks appeared in the TSDC at 90° and 150°C. Low temperature peak may be generated by orientation of the dipole in MAH-PP. High temperature peak may be produced due to migration of homocharge trapped In the phase boundary between crystalline and amorphous region of the blendmers. It was found that the blendmer can be used as an electret air filter material