Bridging the Thermal Divide: Nano-Architectonics and Interface Engineering Strategies for High-Performance 2D Material-Based Polymer Composites

Polymeric materials play a crucial role in thermal management because of their balanced mechanical and insulating properties. However, when combined with two-dimensional (2D) nanosheets, their low thermal conductivity is limited by interfacial thermal resistance (ITR). Although 2D nanosheets can improve the thermal performance of composites, aggregation and ITR are still major obstacles. This review analyzes the relationship between ITR and heat transfer efficiency at 2D nanosheet-polymer interfaces, examining factors like geometric mismatch, phonon scattering, and interphase bonding. It summarizes theoretical models and experimental methods for measuring ITR, focusing on interfacial modification strategies such as covalent functionalization and gradient nanostructuring, which enhance phonon coupling and filler dispersion to reduce ITR. Studies show that customized interfacial layers can lower ITR and boost composite thermal conductivity. The review also highlights challenges in scalable modification and optimization, and suggests future research should combine experiments and simulations to design high-performance 2D material-polymer composites with low ITR.