Comparative analysis of nitride and oxide based nano fillers for polypropylene insulation

Polypropylene (PP) is a promising insulation material for high-voltage direct current (HVDC) cables due to its electrical, thermal, and chemical stability. However, limitations such as high thermal expansion coefficient, low thermal conductivity, and poor flame retardancy restrict its direct application. This study investigates incorporating nano-scale oxide (MgO) and nitride (AlN) fillers into PP via solution blending to enhance dielectric performance. Nanocomposites with varying filler concentrations were prepared, and their AC breakdown strength and DC conductivity were evaluated. Results show that PP filled with 3 wt% AlN and 3 wt% MgO exhibited improvements in AC breakdown strength 15.4% and 13.82%, respectively compared to pure PP. DC conductivity analysis indicated reduced leakage current for nanocomposites at optimal filler concentrations, supporting their suitability for HVDC insulation. The incorporation of oxide and nitride nano-fillers into PP matrix enhanced electrical insulation characteristics, confirming these nanocomposites' potential for advanced HVDC cable applications