Thermal, Mechanical, and Electrical Properties of EPDM/ZnO Nanocomposites for High Voltage Insulators Under the Effect of Gamma Radiation

The demand for lowering the overall costs is one of the main factors driving the expanding market for alternative materials in high-voltage insulating components. Polymer insulators provide several benefits as compared with conventional materials such as glass and ceramic insulators. In addition to the benefits of nanotechnology through different applications, this article studies and evaluates the impact of zinc oxide (ZnO) nanoparticles on the thermal, mechanical, and electrical behaviors of high-voltage electrical insulations composed of ethylene propylene diene monomer (EPDM) with and without a certain dose of gamma radiation. ZnO nanoparticles were introduced to the EPDM sample at different weight percentages (0%, 0.1%, 0.3%, and 0.4%). Scanning electron microscopy (SEM) was used to analyze and characterize the microstructure of samples. Measurements of the mechanical and thermal properties of the formed composites were performed. After that, the prepared samples were tested for dielectric properties, which included the ac breakdown strength (BDS) and dielectric loss factor at room temperature. In addition, the same dielectric properties were measured with a radiation level of 20 kGy. All EPDM nanocomposites have an improvement in mechanical and thermal properties with the increment in the concentration of ZnO nanoparticles up to 0.1% and gamma dose of 20 kGy. With increasing ZnO concentrations up to 0.3% and gamma dose of 20 kGy, ac BDS increases.