Influence of nanoparticle surface treatment on the electrical properties of cycloaliphatic epoxy nanocomposites

This experimental study reports the influence of the surface treatment of silica nanoparticles on the morphology and electrical properties of epoxy composites. (3-Glycidoxypropyl)methyldiethoxysilane was used as a silane coupling agent for the surface treatment of the silica nanoparticles. It was found that the incorporation of the silane onto the surface of silica nanoparticles not only improved the dispersion of the nanoparticles in epoxy, but also improved the electrical properties as compared with the composites filled with unsurface-treated nanoparticles. The surface treatment makes it possible to increase volume resistivity, dielectric strength, and provides an excellent approach able to reduce the dielectric loss of the nanocomposites. It is concluded that the improved properties could be directly ascribed to the good dispersion and special physicochemical characteristics of the surface-treated nanoparticles in the polymer matrix.