Synchronously enhanced thermal conductivity and dielectric properties of silicone rubber composites filled with the AlN‐PPy‐KH570 multilayer core‐shell hybrid structure

The rapid development of lithium battery technology is leading to the increasing miniaturization of electronic devices, thereby elevating the demand for dielectric materials with exceptionally high thermal conductivity and dielectric properties. In this study, the composites were fabricated by integrating multilayer core‐shell hybrid structure particles into silicone rubber (SR). These particles were created by attaching the conductive polymer polypyrrole (PPy) and the silane coupling agent (KH570) onto the surface of highly thermally conductive ceramic particles aluminum nitride (AlN). The combination of PPy and KH570 serves to enhance the interfacial compatibility between AlN and SR, thereby concurrently enhancing the thermal conductivity and dielectric properties of the composites. The experimental results demonstrated that the thermal conductivity of the 50 phr AlN‐PPy‐KH570/SR composite was 0.37 W/(m · K), 1.65 times higher than that of pure SR (0.23 W/(m · K)). Additionally, the dielectric constant of the composite increased to 4.59, 1.32 times that of pure SR (3.48). Moreover, the thermal decomposition temperature of the composite was elevated to 475°C. The synthesized SR composites hold promise for widespread use in miniaturized electronic devices operating in high‐frequency and high‐temperature environments.