Dielectric properties of silica hollow spheres/epoxy nanocomposites

Silica nanostructure hollow spheres were synthesized using template method and the silica hollow spheres/epoxy nanocomposite was prepared by adding the silica hollow spheres modified by aminophenyl trimethoxysilane (APTMOS) into the epoxy resin. Dielectric properties were investigated in terms of frequency and filler concentration. The results showed that the introduction of the silica hollow spheres hardly influenced the thermal stability behavior. With the increase of the silica hollow spheres content, the dielectric permittivity tended to decrease firstly and then increase. While the dissipation factor value increased slightly with an increase in frequency, it still remained at a low level. We found that the silica hollow spheres/epoxy composite containing 3wt% silica hollow spheres content possessed a low dielectric permittivity, a high dielectric strength but a low dielectric loss.