Improved Dielectric Properties of Polypropylene Nanocomposites with BaTiO3Nanoparticles

Abstract

Polymer nanocomposites with improved dielectric permittivity are extremely desirable for the power capacitors. With the existing capacitor polypropylene (PP) film as the substrate, the surface of PP film is coated with a layer of BaTiO3 (BT) with high dielectric constant of nanoparticles. Through the BT layer with high dielectric constant, the dielectric constant of the whole composite dielectric film is improved, and the dielectric loss is controlled at a relatively low level. The organic solvent system of BT paste coating and water system of BT paste coating research were prepared. Two kind of composite dielectric films which are PP/PVDF/BT and PP/BT were prepared by coating. The permittivity of PP/ BT nano-composites with 50 wt% fillers at 1000 Hz was up to 4.49, which was nearly 2 times higher than that of pure PP film. According to the method, a pilot experiment was carried out. The strategy could be extended to a variety of inorganic fillers to improve the dielectric properties of polymer nano- composites for power capacitors.