Enhanced Thermal Conductivity of BN/SR Composites via Biomass-Modification of BN

As microelectronics technology advances and develops, issues such as heat management and reliability of electronic components will become more exposed. Here, this paper explored a green biomass modification method for preparing composites with both good thermal conductivity and dielectric properties. Namely, boron nitride (BN) was first surface coated with the copolymerization product of tea polyphenols and theophylline, both of which can be extracted from tea leaves. Then, through solution blending the coated-BN (BN@TPP) with silicone rubber (SR), the BN@TPP/SR composites were obtained. Owing probably to the coated layer, BN@TPP were more evenly dispersed within the SR matrix, which effectively reduced the interfacial thermal resistance and improved the thermal conductivity of composites. The thermal diffusion coefficient and thermal conductivity of 40 wt% BN@TPP/SR composites reached 0.216 mm 2 /s and 0.462 W/mK, which are higher than BN/SR composites (0.155 mm 2 /s, 0.349 W/mK), respectively. Meanwhile, the 40 wt% BN@TPP/SR composite maintained dielectric constant (3.9 at 1 kHz) and low dielectric loss (0.005 at 1 kHz). In conclusion, this green biomass modification method not only provides a simple and environmentally friendly modification method for BN, but also offers a novel idea that can be applied to the practical preparation of thermally conductive materials for electronic devices. Graphical Abstract