Aging investigation of polyvinyl chloride with zinc oxide micro-fillers for high voltage and high-temperature applications

Abstract This research investigates the behavior of polyvinyl chloride (PVC) micro composites as an electrical insulator under elevated temperature and electrical stress. Zinc Oxide (ZnO) microparticles were incorporated into the PVC matrix. ZnO fillers can improve the thermal stability, hydrophobicity, and electrical resistance of PVC insulation materials. However, it is important to understand how these composites withstand long-term deterioration in harsh environments. Various ZnO concentrations (5%–30%) were used to fabricate micro composites. The samples were subjected to an accelerated aging process to simulate real-world conditions. For 200 h, the aging process used a high voltage of 4 kV DC and a temperature of 65 °C. The samples were analyzed using different analytical techniques to understand how degradation affects various material properties. Visual inspection was employed for any noticeable changes in color and texture. Optical microscopy (OM) is used to detect signs of damage or filler diffusion. Swedish Transmission Research Institute (STRI) Hydrophobicity and Contact Angle Measurements are also employed to check the water-repellency of the samples. Fourier transform infrared spectroscopy (FTIR) was employed to see functional group changes and analyze the behavior, particularly the carbonyl group (C=O) at 1719 cm −1 , which is associated with oxidation and is a significant indicator of degradation. Leakage Current Measurement techniques were also used. UV-visible spectroscopy is employed for the investigation of optical properties and possible degradation-related changes. The 15% ZnO micro composite (PZ-15) exhibited exceptional corrosion resistance. Leakage current tests show significant changes after the aging process. PZ 15 has the best hydrophobicity characteristics, the highest contact angle, and better water resistance. The degree of oxidation is determined by examining the carbonyl peak (C=O) at 1719 cm −1 . It showed a less pronounced peak than the other compounds, indicating a lower level of oxidation. These findings are consistent with previous research showing that ZnO fillers improve the resistance of PVC to different stresses, particularly at higher concentrations. The study emphasizes the importance of optimizing filler materials to improve thermal and electrical stability in their intended applications by combining data from various analytical techniques.