Effect of poly(catechol/polyamine) modified boron nitride on microstructure and properties of thermally vulcanized silicone rubber

With the increasing integration of electronic devices, better heat dissipation of components is urgently required. In this work, a poly(catechol/polyamine) (PCPA) layer is formed on the surface of boron nitride (BN) through chemical modification and then grafted modification by a silane coupling agent. The effect of modified BN (mBN) on microstructure, thermal conductivity and mechanical properties of silicone rubber (SR) is investigated by FTIR, XPS, SEM, thermal and mechanical property testing. Results show that the thermal property of SR composites is improved. When the filling content of mBN is 100 phr, the thermal conductivity of the SR/100mBN composites reaches 1.26 W m(-1) K-1, which is 26% higher than that of the SR/100BN composites. For the purpose of further building a thermal network to improve the thermal conductivity of composites, blocky SiC and flaky BN are introduced into the SR composites. When the ratio of mSiC to mBN is 1:9 in SR composites, the thermal conductivity of the SR/mSiC/mBN composites is 1.35 W m(-1) K-1, which is higher than that of SR composites filled with a single type of filler.

Automated summary

In this study, a PCPA layer was formed on the surface of boron nitride through chemical and graft modification, improving the thermal property of silicone rubber composites. Blocky SiC and flaky BN were then introduced to further enhance the thermal conductivity of the composites.