Evaluation of epoxy nanocomposites for electrical insulation systems

Epoxy nanocomposites can be used as electrical insulation material in various high voltage applications, due to their improved ductility, fatigue resistance, in combination with enhanced electrical properties, compared to the neat epoxy. In the previous work, the mechanisms leading to these improvements in Al₂O₃ nanoparticles filled epoxy nanocomposites were investigated [1, 2]. It was shown that a homogenous dispersion of the nanoparticles in the matrix was required for achieving such improvements. In the present study, different dispersion techniques were used for preparing Al₂O₃/epoxy nanocomposites. The glass transition temperature of all formulations remained the same as the base resin. The nanocomposite with the best dispersion exhibited a 43% increase in strain-at-break, with improved tensile modulus and AC breakdown property (slightly increased mean value and significantly reduced scatter), compared to the base resin.