Learning from Natural Nacre: Constructing Layered Polymer Composites with High Thermal Conductivity

Inspired by the microstructures of naturally layered and highly oriented materials, such as natural nacre; we report a thermally conductive polymer composite that consists of epoxy resin and Al2O3 platelets deposited with silver nanoparticles (AgNPs). Owing to their unique two-dimensional structure, Al2O3 platelets are stacked together via a hot pressing technique, resulting in a brick-and-mortar structure, which is similar to the,one of natural nacre. Moreover, the AgNPs: deposited on the surfaces of the Al2O3, platelets act as bridges that link the adjacent Al2O3 platelets due to the reduced melting point of the AgNPs. As a result, the polymer composite with 50 wt % filler achieves a maximum thermal conductivity of 6.71 W m(-1) K-1. In addition, the small addition of AgNPs (0.6 wt %) minimally affects the electrical insulation of the composites. Our bioinspired approach will find uses in the design and fabrication of thermally conductive materials for thermal management in modern electronics.