Effect of modified ZnO on electrical properties of PP/SEBS nanocomposites for HVDC cables

Polypropylene (PP) has the potential to be used as insulation for high voltage direct current cables due to its high melting point, excellent recyclability and electrical insulation properties. The PP/SEBS composites filled with surface-modified ZnO (m-ZnO) nanoparticles were fabricated through melt blending. Scanning electron microscopy (SEM) showed that the m-ZnO nanoparticles were well dispersed in the PP/SEBS matrix. With doping of 0.5 wt% m-ZnO, the DC breakdown strength, space charge suppression and mechanical properties of the PP/SEBS were remarkably improved, and their DC conductivity was found to be lowered. Moreover, the incorporation of m-ZnO has little effect on the melting and crystallization process as well as dielectric properties of the PP/SEBS. Thus, the PP/SEBS/m-ZnO composites have shown promise to be used as insulation for recyclable HVDC cables.