Tailoring the properties of epoxy/silicone blends for high-voltage capacitor applications

In recent decades, high dielectric constant ( k ) polymer nanocomposites have proved excellent potential in dielectric and energy storage applications. Epoxy/silicon rubber composite materials have shown promising properties in applications such as high-voltage insulation. Three types of nanomaterials (SiO 2 , TiO 2 , and TiO 2 @SiO 2 ) with distinct intrinsic properties are carefully chosen to build high- k epoxy/silicone polymer nanocomposites in this study. To raise the value of K , this work tailored the polarizing ability or permittivity of dielectric material by inserting different weight ratios of nano-fillers (SiO 2 , TiO 2 , TiO 2 @SiO 2 ) in the base matrix of dielectric material in epoxy and silicon rubber blends. With a base matrix containing 75% epoxy and 25% liquid silicone rubber concentration, the maximum value of K obtained is K  = 158 for 5% TiO 2 and there is an increase in the dielectric strength to 398 kV/mm. The obtained results indicate that, among the three different kinds of epoxy/silicone, TiO 2 @SiO 2 has the most potential in enhancing the energy storage capabilities of the proposed nanocomposites, owing to the largest increase in k while maintaining low dielectric loss and leakage current.