Effects of Key Parameters on Thermal Conductivity of Carbon Nanotube–Epoxy Composites by Molecular Dynamics Simulations

The application of carbon nanotube (CNT)-reinforced epoxy matrix composites (CRECs) has attracted extensive attention in various industrial sectors due to the significant improvement of material properties imparted by CNTs. The thermal behavior of these nanocomposites is governed by complex heat transfer mechanisms operating at different scales, resulting in a complex relationship between the effective thermal response and the microstructural characteristics of the composite. In order to fundamentally understand the thermal behavior of the CRECs on the nanoscale, in this study, molecular dynamics (MD) simulation methods were used to investigate the thermal conductivity of CRECs, focusing on the effects of key parameters such as the length and volume fraction of CNTs, the degree of cross-linking within the epoxy matrix, and the temperature on the overall thermal properties. First, the thermal behavior of the epoxy matrix was simulated and analyzed. This approach allowed the isolation of the intrinsic thermal response of the epoxy resin as a benchmark for evaluating the enhancement introduced by CNT reinforcement. By systematically varying those key parameters, the study comprehensively evaluates how nanoscale interactions and structural modifications affect the overall thermal conductivity of CRECs, providing valuable insights for optimizing their design for advanced thermal management applications. The simulation results were validated by comparing them with experimental data from literature and analytical predictions. The results show that for the configurations examined, the thermal conductivity of CRECs increases with increasing CNT length and volume fraction, epoxy cross-linking degree, and the system temperature. From a broader perspective, the approach presented here has the potential to be applied to study a wide range of materials and their properties.