Synergetic effect of hybrid fillers of boron nitride, graphene nanoplatelets, and short carbon fibers for enhanced thermal conductivity and electrical resistivity of epoxy nanocomposites

Abstract

High filler loading in polymer alone cannot meet the increasing requirements of the electronic industry, so the hybrid fillers with unique advantages have been developed. In this work, chemical exfoliation and mechanical mixing are combined to disperse hybrid fillers of graphene nanoplatelets (GNPs) and boron nitride (BN) nanoplatelets inside short carbon fibers (SCF) based epoxy matrix. Such surface modified hybrid fillers/epoxy nanocomposites exhibit a high thermal conductivity of ca. 0.8 W m−1 K−1 and an electrical volume resistivity of ca. 6.41 × 1015 Ω cm at a low filler loading of 3 wt% SCF + 5 wt% modified GNP-BN. Furthermore, the thermal stability, heat dissipation and absorption properties are enhanced for the ternary hybrid fillers/epoxy nanocomposites. Overall, such a system offers an outstanding approach for the electronic industry to enhance the thermal conductivity without compromising the electrical insulation property of epoxy materials.