Theoretical Prediction of Heat Transport in Few-Layer Graphene/Epoxy Composites

Graphene is widely employed to improve the overall thermal conductivity of polymer composites because of its remarkable thermal conductivity. However, the magnitude of its improvement of thermal conductivity is far below the values expected from the remarkably high thermal conductivity of graphene and is very much less than the production cost of graphene, greatly limiting its large-scale applications in the field of thermal management. Therefore, understanding heat transport behaviors within the polymer composites and studying the related influential factors are very important. Here, heat transport behaviors within few-layer graphene (FLG)/epoxy composites are studied using molecular dynamics (MD) simulations. The influences of interfacial thermal resistance, FLG volume fraction and FLG length on overall thermal conductivity of the composites are specifically analyzed, finding that there is a significant interfacial thermal resistance between FLG and epoxy because of the mismatch of the phonon vibration power spectrum (VPS). Furthermore, the interfacial thermal resistance, FLG volume fraction, and FLG length play important roles in improving the overall thermal conductivity of FLG/epoxy composites. Our findings provide a better understanding of the heat transport behaviors within polymer composites and should be useful for future development of various thermal management applications.