Ultrahigh Thermal Conductivity of Assembled Aligned Multilayer Graphene/Epoxy Composite

Abstract

The exceptional thermal conductivity of graphene is expected to endow polymer composites with ultrahigh thermal conductivities, which can be even similar to those of some metals such as stainless steel and aluminum alloy. The thermal conductivities of composites prepared by dispersing multilayer graphene (MLG) in epoxy matrix increase only by an order of magnitude over the pure epoxy. However, the improvement has been limited since the large interfacial thermal resistance exists between graphene and the surrounding epoxy. We have reported an extraordinary increase in thermal conductivity of the MLG/epoxy composites through the fabrication of the vertically aligned and densely packed MLG in the epoxy matrix. The ultrahigh thermal conductivity of 33.54 W/(m K) has been achieved in the aligned MLG/epoxy composite (AG/E). The thermal conductivity of AG/E exhibits a positive temperature response related to the aligned structure while increasing the temperature from 40 °C to 90 °C.