Improved thermal conductivity and mechanical property of mercapto group-activated boron nitride/elastomer composites for thermal management

Ionic liquid 1-Ethyl-3-methylimidazolium chloride was employed to promote the exfoliation of hexagonal boron nitride (BN) to fabricate the boron nitride nanosheets (BNNSs). The BNNSs were then surface activated by covalently attaching mercapto groups on their surfaces. The surface-activated BNNS nanoparticles (S@BNNSs) were incorporated in a carboxylated styrene-butadiene rubber matrix for preparing thermal management materials. The developed material was provided with superior mechanical properties, satisfied thermal conductivity and strong storage modulus attributing to the two-dimensional structure of the filler and the enhanced interfacial interaction between the filler and matrix. The filler-filler and filler-matrix networks in the composite system were comprehensively analyzed. The thermal management applications were also demonstrated using an infrared camera and a commercial thermoelectric generator. All the performances demonstrated their potential use as thermal management materials in electronic devices.