Analysis of the influence of interphase characteristics on thermal conduction in surface-modified carbon nanotube-reinforced composites using an analytical model

In this study, the influence of interphase characteristics on thermal conductivity of carbon nanotube (CNT)-reinforced polymer composites was investigated using a thermal resistance theory-based analytical model. Pristine, nitrogen doped, and carboxyl functionalized CNTs were used to verify the effect of surface modifications. Interfacial thermal conductivities of nanocomposites containing three different CNTs were calculated from non-equilibrium molecular dynamics (NEMD) simulations, to analyze the influence of functionalization on the interphase characteristics. Equilibrium molecular dynamics (EMD) simulations of three different CNTs and epoxy matrix were performed to estimate their effective thermal conductivities. The thermal conductivities of the nanocomposites were predicted by applying the results obtained from the MD simulations in the analytical model. The results predicted by the analytical model show that while thermal conduction in the longitudinal direction of the nanocomposites depends on thermal conductive performance of the CNTs, transverse thermal conductivity could be significantly influenced by the interphase characteristics.