Bioinspired Design Strategies and Thermal Transport Mechanisms in Thermally Conductive Composites

Abstract

The rapid development of high-power-density electronics has created increasing demands for thermal management materials, making thermally conductive composites (TCCMs) important candidates for electronic packaging and related applications. Structural design is an effective way to improve thermal transport because it regulates filler distribution and orientation, network connectivity, hierarchical organization, and filler–filler contact. These structural features promote the formation of continuous heat-conduction pathways at relatively low filler loadings, increase filler–filler contact, and reduce polymer-rich interruptions, thereby facilitating phonon transport and lowering the effective thermal resistance of the heat-conduction pathways. Natural materials provide useful inspiration for the design of these architectures, as their transport structures often integrate ordered pathways with disordered or heterogeneous regions, thereby supporting efficient transport while maintaining structural stability. Inspired by such biological systems, bioinspired structural design has become an important route for developing thermally conductive composites with enhanced thermal transport properties. This review summarizes recent progress in bioinspired thermally conductive composites (BTCCMs), with emphasis on fibrous, network, layered, porous, and core–shell structures. For each type, representative biological prototypes, fabrication strategies, and the relationships between structural characteristics and thermal transport performance are discussed. Particular attention is paid to how the structural characteristics of bioinspired structures, including filler alignment, spatial distribution, network connectivity, pore morphology, hierarchical organization, and interfacial contact, affect phonon transport and thermal conduction. Representative applications in high-power electronics, aerospace, and flexible electronics are also introduced. Finally, the main challenges in quantitative structure–property correlation, interfacial thermal resistance, and scalable fabrication are discussed, together with perspectives for the development of next-generation BTCCMs.