Thermal Conductivity of Graphene Nanoplatelet/Carbon Fiber/Cycloaliphatic Epoxy Hybrid Composites: Multiscale Modeling

Abstract

Graphene nanoplatelet (GNP)/Carbon fiber/cycloaliphatic epoxy (CE) hybrid composites are computationally modeled using a multiscale modeling approach to predict the thermal transport behavior. Equilibrium molecular dynamics simulations are performed to obtain the in-plane and out-of-plane thermal conductivities at the molecular level for GNP/cured CE with different levels of GNP dispersion, namely, 1, 2, 3, and 4 layer(s) of graphene. The thermal conductivities are randomized by arithmetic averaging. The thermal conductivities for 1 to 8 wt% of GNP are predicted using micromechanics analysis code based on generalized method of cells (MAC/GMC) and compare well with experiments. The effective thermal conductivities of the hybrid composites are also determined by using MAC/GMC and compared with experimental specimens. The axial thermal conductivity of the hybrid composite model slightly increases due to the amount of graphene. However, the transverse thermal conductivity is predicted to be improved up to 132% relative to no GNP loading.