Munshi Jasimuddin, Zhijie Wang, Jiajing Huang*, Jiawang Wen*, Yue Lin*

Cite this article: https://doi.org/10.1016/j.cjsc.2026.100909

Publication date:

Keywords: Thermally conductive polymer composites; Thermal conductivity; Structure-property relationships; Thermal metrology; Microstructure design; Thermal interface materials (TIMs)

ABSTRACT

Polymers are indispensable in modern technologies because of their lightweight nature, processability, and mechanical compliance, yet their inherently low thermal conductivity limits thermal management in applications ranging from flexible electronics and energy devices to thermal interfaces. Recent progress shows that polymer thermal transport is highly designable when viewed through a hierarchical structure–property framework that spans molecular order, mesoscale morphology, and composite architectures. This review summarizes advances in thermally conductive polymers and polymer-based composites by connecting multiscale modelling, reliable metrology, and microstructure engineering. We first discuss theoretical and computational approaches that capture phonon-dominated transport in disordered chains and quantify interfacial thermal resistance at polymer–filler interphases. We then compare key measurement techniques and highlight how test configuration, pressure, anisotropy, and sample preparation affect the extracted thermal conductivity and thermal resistance metrics. We further analyze material strategies at three levels: (i) molecular design and chain alignment to increase intrinsic polymer thermal transport, (ii) filler selection and interphase engineering to reduce vibrational mismatch and interfacial resistance, and (iii) architected networks, orientation, and hierarchical pathways to enable efficient, scalable heat conduction. Finally, we outline emerging opportunities and remaining challenges in establishing transferable design rules, standardized metrology, and manufacturable routes toward high-performance, reliable thermal management polymers and composites.