Two-dimensional hexagonal boron nitride (h-BN) has excellent and useful mechanical and thermal properties, and can be used as a novel filler to enhance the thermal conductivity of polymer composites. We prepared exfoliated h-BN nanoplatelets (BNNP) with hydroxyl functional groups using a hydroxide-assisted ball milling process, and demonstrated the enhanced thermal conductivity of its epoxy nanocomposites. The prepared BNNP are highly soluble and retain their in-plane structure. The dielectric constant and dielectric loss of the nanocomposites increase with the addition of BNNP owing to interfacial polarization by the large surface area of BNNP and the ionic and electronic relaxation polarizations by the surface functional groups on the BNNP. Notably, the thermal conductivity of the epoxy nanocomposites with 10% mass fraction of BNNP was 0.57 W/m·K, which is 2.85-times higher than that of neat epoxy. Finally, compared with neat epoxy, BNNP nanocomposite exhibits excellent heat dissipation capability in flat chip packaging. This enhanced performance is ascribed to the high quality and dispersion of the BNNP and their strong interfacial bonding with the epoxy matrix, which is produced by the hydroxyl functional groups on the BNNP. The overall results suggest that BNNP nanocomposites have strong potential for application as electronic packaging materials.

二维六方氮化硼（h-BN）具有出色且有用的机械和热学性质，可用作增强聚合物复合材料导热性的新型填料。我们使用氢氧化物辅助球磨工艺制备了带有羟基官能团的h-BN纳米片状脱落薄片，并证明了其环氧纳米复合材料的导热性得到了提高。制备的BNNP具有高度溶解性，并保持其面内结构。纳米复合材料的介电常数和介电损耗随BNNP的增加而增加，这归因于BNNP的大表面积引起的界面极化以及BNNP上的表面官能团引起的离子和电子弛豫极化。值得注意的是，BNNP质量分数为10％的环氧纳米复合材料的导热系数为0。57 W / m·K，是纯环氧树脂的2.85倍。最后，与纯环氧树脂相比，BNNP纳米复合材料在扁平芯片封装中具有出色的散热能力。增强的性能归因于BNNP的高质量和分散性以及它们与环氧基质的牢固界面键合，后者是由BNNP上的羟基官能团产生的。总体结果表明，BNNP纳米复合材料具有用作电子包装材料的强大潜力。它是由BNNP上的羟基官能团产生的。总体结果表明，BNNP纳米复合材料具有用作电子包装材料的强大潜力。它是由BNNP上的羟基官能团产生的。总体结果表明，BNNP纳米复合材料具有用作电子包装材料的强大潜力。