Enhancement of Thermal Energy Transport Across Graphene/Graphite and Polymer Interfaces: A Molecular Dynamics Study

Understanding thermal energy transport in polymeric nanocomposite materials is important to the engineering of polymer composites with better engineered heat transfer properties. Interfacial thermal resistance between the filling particles and the polymer matrices is a major bottleneck for the thermal conductivity improvement of polymer composite materials. Here, thermal energy transport in graphene/graphite-polymer (paraffin wax-C30H62) composite systems are systematically studied using molecular dynamics simulations. The influences of graphene size, interfacial bonding strength, and polymer density on the interfacial thermal transport are studied. According to the simulation results, approaches to improve interfacial thermal transport are proposed. Spectral analysis is performed to explore the mechanism of thermal transport. It is found that thermal energy transport across graphene/graphite-polymer interfaces can be enhanced by increasing the polymer density and graphene size or forming covalent bonds between the graphite edges and polymer molecules. The results offer valuable guidance on improving thermal transport properties of polymeric nanocomposite.