Dielectric properties and surface potential decay characteristics of low density polyethylene/ZnO microvaristor composites

This paper focuses on the effects of submicron ZnO microvaristors on the microstructure and electrical properties of low density polyethylene (LDPE) based composites. The submicron ZnO microvaristors are obtained by ball milling method and are used as a filler of LDPE based composites. The submicron composites with the filler loading of 0, 10, 20, 30 and 40 wt% are prepared by melt-blending method. The morphology, crystallization behavior, dielectric properties and surface potential decay characteristics are characterized by scanning electron microscope, differential scanning calorimetry, dielectric spectrum and surface potential decay measurement, respectively. Experimental results show that the average speed of the surface potential decay characteristics of LDPE based composites increases distinctly with the increasing filler loading. The submicron ZnO microvaristors are in favorable to suppress the charge accumulation of LDPE based composites and can be used to regulate the charge distribution in electrical and electronic equipment.