A Thermal Conductivity Model for CNT Polymer Composites Considering Curvature, Orientation, and Interfacial Resistance

A theoretical model is proposed to predict the effective thermal conductivity of CNT–polymer composites by coupling interfacial thermal resistance, CNT waviness, orientation, and aggregation effects. A stepwise-discrete angle and equivalent length method are used to characterize heat flux loss in curved CNTs. The model is validated against experimental data and compared with the Hasselman–Johnson and Deng models. Results show that the present model greatly improves prediction accuracy and effectively avoids overestimation under low and moderate loadings. This work provides a reliable theoretical approach for the design and optimization of high-performance thermally conductive composites in electronic packaging and aerospace applications.