Influence of Nanoparticles and Accelerated Electrothermal Stress on the Characterization and Electrical Properties of High Voltage Polyamide Insulation /

Abstract

This study investigates the electrothermal aging effects on polyamide and its nanocomposites with various nano zinc oxide (ZnO) filler concentrations. The primary objective was to figure out how these nanocomposites performed under accelerated electrothermal aging conditions. The study included fabrication of neat polyamide (PA0) and its nanocomposites containing 1 wt%, 3 wt%, 5 wt%, and 7 wt% ZnO fillers, which were then subjected to 300 hours of accelerated electrothermal aging in an electrothermal chamber. The nanocomposites' performance has been evaluated using several analytical techniques, including Xray Diffraction (XRD), optical microscopy (OM), hydrophobicity measurements, contact angle, Fourier Transform Infrared (FTIR) spectroscopy, AC and DC leakage current measurements, UV-Vis spectroscopy, and temperature and frequency dependent dielectric properties. These methods confirmed that the materials degraded progressively due to severe thermal and electric stresses. The contact angle measurements indicated variable hydrophobicity among the samples, with PA3 (3 wt% ZnO) exhibiting the highest contact angle, indicating higher water repellency. Leakage current measurements found very minor variations between samples, however structural degradation studies revealed a considerable reduction in C-C stretching, with PA3 showing the smallest decrease. The FTIR spectra exhibited an increase in carbonyl groups, confirming oxidation. In contrast to other samples, the nanocomposite with 3 wt% ZnO performed better, with lower leakage current, negligible surface degradation, and a greater band gap energy of 5.93 eV. The results showed that using an optimal concentration of ZnO nanofillers optimizes the electrothermal stability and performance of polyamide insulators. This study highlights the potential of ZnO-enhanced polyamide nanocomposites as suitable materials for high-voltage insulation applications, providing greater resilience and a longer lifespan in extreme environments.