Dielectric performance of nanocomposites synthesized by poly(ethylene oxide)-like film coated silica nanoparticles by plasma polymerization

Nanocomposites have been recognized to possess favorable dielectric and electrical insulation properties. However, poor dispersion of the nanofillers and weak filler-matrix bonding may significantly limit the performance of nanocomposites. The present study proposed using plasma polymerization method to coat poly(ethylene oxide)-like films on SiO₂ nanoparticles in order to improve the dispersion and enhance the filler-matrix interaction of the epoxy resin-based nanocomposites. Results show that the epoxy resin/SiO₂ nanocomposites with the modified nanoparticles possess longer endurance against electrical ageing. The initiation of electrical trees is delayed and the radial extent of the tree is smaller as compared to the nanocomposites with the as-received nanoparticles. The dielectric constant of the nanocomposites with plasma polymerized fillers is also reduced over a wide range of frequencies.