Investigation of Polypropylene Nanofiller Multi-Element Oxide Insulation Material for Mitigating Electrical Breakdown in High-Voltage Insulation Applications

ASM Sc. J., 21(1), 2026

Published on June 30, 2026

https://doi.org/10.32802/asmscj.2026.0329

Author: Aizat Azmi, Nordiana Azlin Othman, Md Aris Nor Asyidi Md Nadzir

Abstract

This paper examines the dielectric behaviour of pure polypropylene (PP) and its nanocomposites modified with 2 wt% of different multielement oxide nanofillers which is magnesium aluminate (MgAl₂O₄), calcium carbonate (CaCO₃), and zinc ferrite (ZnFe₂O₄). Differential scanning calorimetry (DSC) and Fourier-transform infrared spectroscopy (FTIR) were employed to assess thermal and chemical characteristics, respectively. The results indicate that pure PP demonstrates the highest direct current (DC) breakdown strength, reaching about 327 kV/mm. However, the breakdown strength drops to 271 kV/mm when 2 wt% CaCO₃ is added, w ith further reductions observed for ZnFe₂O₄ (239 kV/mm) and MgAl₂O₄ (174 kV/mm). These reductions are believed to be due to morphological changes introduced by the nanofillers, which act as nucleating agents, as confirmed by DSC analysis. Overall, the study emphasises that the type of nanofiller plays a decisive role in shaping the dielectric performance of PP-based composites.

Keywords: high voltage insulation, multi-element oxide, nanocomposites