Surface modification of chemically-inert hexagonal boron nitride (h-BN) to reduce its interfacial thermal resistance remains problematic, thereby hindering its application in thermal conductive composites. Here, poly(glycidyl methacrylate) (PGMA) chains were grafted onto the surface of h-BN by using a simple free radical polymerization. The prepared PGMA grafted h-BN (h-BN-PGMA) was incorporated into epoxy (EP) to enhance the thermal conductivity of EP composites. Adding 3, 9 or 15 vol% of h-BN-PGMA into EP leads to 60%, 203% or 505% increases in thermal conductivity, respectively. Meanwhile, the surface modification of h-BN is benefit to enhance the compatibility between the fillers and EP matrix, which reduces the apparent viscosity of composite materials. Furthermore, compared with EP/h-BN, EP/h-BN-PGMA composites with the same filler-loading exhibit higher storage modulus and glass transition temperature. Additionally, the dielectric constant of the composites hardly depends on the testing frequency while the dielectric loss maintained at a very low level.

化学惰性六方氮化硼（h-BN）的表面改性以降低其界面热阻仍然存在问题，从而阻碍了其在导热复合材料中的应用。在这里，通过使用简单的自由基聚合，将聚（甲基丙烯酸缩水甘油酯）（PGMA）链接枝到h-BN的表面上。将制备的PGMA接枝h-BN（h-BN-PGMA）掺入环氧树脂（EP）中，以增强EP复合材料的导热性。向EP中添加3、9或15体积％的h-BN-PGMA导致增加60％，203％或505％s在热导率上分别。同时，h-BN的表面改性有利于增强填料与EP基体之间的相容性，降低复合材料的表观粘度。此外，与EP / h-BN相比，具有相同填充量的EP / h-BN-PGMA复合材料具有更高的储能模量和玻璃化转变温度。另外，复合材料的介电常数几乎不取决于测试频率，而介电损耗却保持在非常低的水平。