Scalable fabrication of thermally conductive elastomer/boron nitride nanosheets composites by slurry compounding

So far, most of the preparation methods for polymer/boron nitride nanosheets (BNNSs) composites are not suitable for mass production. Here, cost-effective and environmentally friendly water/ethanol were selected as the solvents to prepare BNNSs slurry on large scale by liquid exfoliation/solvent exchange. The slurry was then compounded with styrene-butadiene rubber (SBR) to form the rubber/BNNSs composites via conventional two-roll milling. The sulfide-containing silane was introduced to modify the interface between BNNSs and the rubber. The silane modified BNNSs (Si-BNNSs) has been characterized by FTIR, XPS and TGA. It is found that, with in situ modification of the silane, the rubber/BNNSs composites exhibited significantly improved thermal conductivity. With 10.5 vol% Si-BNNSs incorporated, the thermal conductivity of the composites is increased by 253%, comparing to the neat SBR. Meanwhile, the mechanical properties of the composites are simultaneously largely enhanced. The scalable yet environmentally-friendly slurry approach paves the way for industrial-scale utilization of BNNSs in thermally conductive polymer composites.