Effect of polymer blending on the dipoles of constituent polymers

Blended polymer films of polymethylmethacrylate:polyvinyl acetate, polyethylene:polyvinyl-chloride and polycarbonate:polypropylene were prepared either by the solution cast technique or by compression molding. Thermally stimulated discharge current studies on the thermoelectrets of these blends were carried out at different fields and temperatures. The results indicate that the polarization state of these blends is mainly due to charge-carrier trapping that leads to induced dipole formation. It is found that the dipoles in the polyblends are so constrained that their contribution to the total polarization of the blend is negligible