Curing kinetics and dielectric properties of epoxy based nanocomposites

In this paper, epoxy based nanocomposites were prepared by adding inorganic alumina nano-particles and organic nitrile rubber nano-powders. The effects of two kinds of nano-particles on the curing kinetics of epoxy nanocomposites were investigated by differential scanning calorimetry (DSC). The dielectric properties of nanocomposites were evaluated in terms of volume resistivity (ρV), dielectric loss tangent (tgδ) and dielectric constant (ε). The results show that the activation energy of nanocomposites with single kind of nano-particles was decreased while the one with two kinds of nano-particles was increased. The same curing mechanism of nanocomposites as epoxy resin was revealed according to the similar reaction order. The volume resistivity of the nanocomosites was in the same order with the pure epoxy resin. Meanwhile, the dielectric constants of the nanocomposites were increased thanks to the higher dielectric constants of alumina and nitrile rubber than epoxy resin. The mixed nano-particles contributed more to the dielectric constants and the dielectric loss tangent of the nanocomposites.