Spraying EPDM@NPs as an efficient strategy for polyethylene-based high-voltage insulation

Abstract

The synthesizing strategy of grafting a structure similar to the polymer matrix on the nanoparticles (NPs) surface is highly efficient in improving the insulating properties of polymers. The comprehensive study consisting of quantum chemical simulations and electrical properties at elevated temperatures shows that under high temperatures and strong direct current (DC) electric fields, spraying an ultra-low concentration of 0.0001 wt% EPDM@ZnO at the cross-linked polyethylene (XLPE) interface can reduce its DC electrical conductivity, suppress space charge accumulation and increase the DC breakdown strength. The EPDM@ZnO inherits the hydrophobic properties of graft material EPDM. Adding very low concentrations such as 0.0001 wt% minimizes the impact on material cleanliness, i.e., impurities, and facilitates the uniform dispersion of nanoparticles in the host polyethylene matrix, thereby overcoming nanoparticle agglomeration. The reported synthesis strategy of nanoparticles and preparation process is believed to provide new insights for developing future ultra-high voltage direct current cables and can be widely applied to nano-polymer modification applications of coatings, structural materials, and interface materials.