Imidazolium-optimized conductive interfaces in multilayer graphene nanoplatelet/epoxy composites for thermal management applications and electroactive devices

Abstract

Abstract Imidazolium-based ionic liquid-modified multilayer graphene nanoplatelets (IL@GNPs) derived from atmospheric-pressure plasma-induced expanded graphite (p-EG) were prepared and employed to obtain conductive filler–matrix networks in epoxy (EP)-based electroactive devices. The thermal conductivity, electrical properties, and thermo-physical properties of the fabricated composites were evaluated as a function of the IL@GNPs content. Large volume expansion of the plasma-induced EG and few-layer IL@GNPs were observed. The thermal and electrical conductivities and thermo-physical properties of the developed EP/IL@GNPs composites were significantly enhanced compared to the EP/expandable graphite (EaG) and EP/GNPs composites at the same filler concentration, attributed to the well-exfoliated and IL-functionalized IL@GNPs, which can efficiently construct a conductive filler network in the matrix, and optimize the thermal interface between the filler and the polymer matrix. The designed polymeric materials could be potentially applied in thermal interface materials and other high-performance electroactive devices.