Editorial: Polymers for high electric field applications

Polymers have been found wide applications in power equipment, due to their excellent electric 7 insulation properties, energy storage performance, and mechanical behaviors. The continuous 8 development of electric systems towards higher voltage, larger capacity, miniaturization and stringent 9 environment has posed an increasing challenge for polymeric materials. The attention has been 10directed on polymeric dielectric properties, charge transportation/space charge, electric breakdown, 11 interfacial phenomenon, treeing etc. to increase the electric performances. These properties rely on 12 the morphological and molecular structure of the polymer, in particular on its crystalline and 13 amorphous phase, long-period and interfacial structures. This authors in research topic have reported 14 the in-depth investigations in this field. 15For power cable insulation polymers, the working voltages for the manufactured cable have been up 16 to 500kV for HVAC and 640kV for HVDC applications, and the thickness of insulation is enlarged, 17 leading to the difficulty on the removal of byproducts caused by the crosslinking of polyethene (PE). 18In the case of HVDC cable, the residual crosslinking byproducts may significantly influence the 19 electric field distribution through affecting the conductivity of crosslinked polyethene (XLPE). F.