Effect of pre-treatment of nanofillers on the dielectric properties of epoxy nanocomposites

Early researches show that the nano filler dispersion has a significant effect on the dielectric properties of resulting epoxy nanocomposites. In this paper a comparative study on the dielectric permittivity, AC breakdown behaviours and glass transition temperature of epoxy nanocomposites loaded with both treated and untreated nano SiO₂ fillers has been carried out. The epoxy resin (LY556), commonly used in power apparatus, was used to study the dielectric behaviour of epoxy. Silane was used as a coupling agent to pre-treat the nano particles. The results indicate that the surface treatment of nanoparticles has a strong effect on the dielectric properties of resulting nanocomposites as surface treated nanoparticles with better dispersions is believed to hinder the polymer chain mobility and charge transportation through the interface region between epoxy and nanoparticles .