Preparation and properties of nano MgO/low density polyethylene composites for high-voltage direct current cables

Nano MgO particles without hydroxyl group (—OH) on surface were prepared through hydrothermal method, and 10wt% MgO/low density polyethylene (LDPE) composites were prepared by master batch method. The space charge characteristics of nano MgO/LDPE composites under 70 kV/mm direct current fields were studied. The dispersion effect of nanoparticles and the application promotional value in industry of this method were also evaluated. The results show that the effects of surface hydroxy on variable temperature volume resistivity and dielectric properties of nano MgO/LDPE composites were not remarkable, while space charge accumulates increase. When the concentration of nano MgO is 1wt%, composite presentes the excellent electrical properties.