Dielectric performance of Polymer Nanocomposites Synthesized by Atmospheric-pressure Plasma-treated Silica Nanoparticles

W. Yan
University of New South Wales, AU

Keywords: nanocomposite, dielectrics, plasma, partial discharge, dielectric constant


The incorporation of nanoparticles can effectively enhance the dielectric performance of polymers. However, the organic-inorganic incompatibility prevents the nanocomposites from obtaining the desired properties. To overcome this issue, coupling agents have been used to coat organic groups on the surface of the nanoparticles. However, the particles poorly interact with the polymer matrix, leading to unsatisfactory improvements of the nanocomposites. In this study, we use atmospheric-pressure plasma to activate the surface of the silane coated nanoparticles prior to mixing them with the polymer. Results show that the silane groups on the surface of the nanoparticles are activated, leading to the formation of chemical bonds with the surrounding polymer matrix. The dispersion uniformity of the nanoparticles is not affected. However the degree of cross-linking is reduced as a result of the incorporation of the reactive nanofillers. The breakdown strength and the endurance of the plasma-treated SiO2/ epoxy resin nanocomposite are significantly increased. Also observed is a decrease of the dielectric constant over the frequency range of 100 Hz to 100 kHz. The atmospheric-pressure plasma treatment method is generic and can be utilized in the production of high-performance and reliable organic-inorganic nanocomposites.