The heat accumulation has become a serious problem due to electronic devices towards high power and intelligence. Highly thermal conductive and electrical insulating polymeric composites are potential to solving the overheating problem of electronic devices. Herein, boron nitride nanosheets (BNNSs) were successfully exfoliated by shear forces generated high pressure. Then, BNNSs and sphere BN (S-BN) were added into the polydimethylsiloxane (PDMS) matrix to prepare composites. The thermal conductivity of the BNNSs/PDMS composites achieved 1.16 W m-1 K-1 at 35 wt% fillers, which is almost 5 times that of pure PDMS and higher than that of S-BN/PDMS composites. The efficient thermal paths were constructed by BNNSs in PDMS matrix leading to enhancing the thermal transport in polymer matrix. Meanwhile, the volume resistances and breakdown strength of BNNSs/PDMS composites reach 7.5 × 1013 Ω cm and 39.8 V/μm, which are attributed to the superior electrical insulating properties of BNNSs. The result shows that the excellent thermal conductivity and electrical insulation properties of BNNSs/PDMS make it a promising application in the field of thermal management.

由于电子设备朝着大功率和智能化的方向，热量累积已成为一个严重的问题。具有高导热性和电绝缘性的聚合物复合材料具有解决电子设备过热问题的潜力。在此，氮化硼纳米片（BNNSs）被产生的高压剪切力成功剥离。然后，将BNNS和球形BN（S-BN）添加到聚二甲基硅氧烷（PDMS）基质中以制备复合材料。BNNSs / PDMS复合材料在35 wt％的填料下的热导率达到1.16 W m-1 K-1，几乎是纯PDMS的5倍，比S-BN / PDMS复合材料的高。BNNS在PDMS基质中构建了有效的热路径，从而增强了聚合物基质中的热传递。与此同时，BNNSs / PDMS复合材料的体积电阻和击穿强度分别达到7.5×1013Ωcm和39.8 V /μm，这归因于BNNSs的优异电绝缘性能。结果表明，BNNSs / PDMS优异的导热性和电绝缘性能使其在热管理领域具有广阔的应用前景。