Molecular Dynamics Simulation of Key Physical Properties of Graphene Oxide / Epoxy Resin Nanocomposite Dielectrics

With the rapid development of power systems, greater demands have been put on the physical properties of insulating materials. Doping with functional nanomaterials is an effective method to modify such materials. In this work, epoxy resin is doped with graphene oxide at different concentrations by molecular dynamics simulation. After doping, the relative permittivity, thermal expansion coefficient, molecular chain segment motion, and free volume ratio of the system is decreased, and the thermal conductivity, Young's modulus, bulk modulus, and shear modulus are enhanced; changes in glass transition temperature are negligible. Doping with graphene oxide improves the thermal and mechanical properties, and this improvement increases with increasing dopant amount. However, when dopant concentration is too high, agglomeration occurs, which hinders insulation performance. Therefore, the optimum doping concentration is the highest at which no agglomeration occurs. This paper provides guidance for the future modification of insulating materials.