Maxwell-Wagner Dielectric Polarization in Polypropylene Film/Aromatic Dielectric Fluid System for High Voltage Capacitor Use

The chemical interaction between biaxially-oriented polypropylene film and diarylalkane has been investigated by studying the dielectric properties of the polypropylene film impregnated by the fluid. It was found that the ß dispersion in its dissipation factor-temperature relationship is related to the segmental motion of the amorphous phase existing in the film, and that the a dispersion is connected with the Maxwell-Wagner type dielectric polarization at the surface of the crystalline phase in the film. Furthermore, it was demonstrated that the dissipation factor at the ß dispersion temperature correlates well with the dissolution of the film into the fluid, and that the dissipation factor at the a dispersion temperature correlates closely with the oil absorption of the film immersed in the fluid.