Voltage Stabilizer Grafted Silica Nanoparticles for Significantly Enhanced Breakdown Strength Potential Thermoplastic Polypropylene Insulation

Recyclable power cable insulation received significant attention because of several merits. Thermoplastic polypropylene is a promising candidate because of its high melting temperature and the similar dielectric properties with polyethylene. However, the current commercially available polypropylene can't meet the requirement of power cable insulation, particularly HVDC cables. Improving the electrical properties of polypropylene is one main task. In this work, we report the role of SiO
₂
nanoparticles grafted by newly designed and synthesized voltage stabilizer on electrical property improvement of isotactic polypropylene. The addition of voltage stabilizer grafted SiO
₂
nanoparticles can significantly increase the breakdown strength and suppress the space charges. In the case of 1 wt% voltage stabilizer grafted SiO
₂
, 29.7% enhancement of breakdown strength was obtained in the nanocomposites. The results were tentatively explained according to the measured surface potential decay and other data such as microstructure of the polypropylene. This current study clearly shows the importance of voltage stabilizer grafted SiO
₂
nanoparticles in property improvement of polypropylene insulation.