The development of low loading fraction nanoscale reinforcements that can be used to improve the dielectric and thermal properties of a polymer remains a challenge by the reason of the insurmountable difficulties with exfoliation and dispersion of polymer nanocomposites. Here, we combined noodle-like boron nitride nanoribbons (BNNRs) with epoxy resin (EP) by a facile in situ synthesis. The hydroxyl and amino on the BNNRs surface can not only improve dispersibility but also conduct the formation of EP with BNNRs by the in situ ring-opening reaction. The thermal behavior, dielectric properties, and thermal conductivity of BNNRs/EP nanocomposites with different BNNRs contents were investigated. At an extremely low BNNRs loading fraction of 1 wt%, the thermal conductivity of the nanocomposite increased 48%, which is attributed to the long continuous heat conduction path formed by the strong integration of BNNRs and EP. In addition, the electrical breakdown strength increased from 95.58 to 159.17 kV·mm⁻¹ as the BNNRs content increased, while the nanocomposites maintained acceptable dielectric properties. The results indicate the potential for BNNRs as a new class of nanofiller for dielectric polymers.

中文翻译：

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原位合成具有增强的热和介电性能的氮化硼“纳米线”基环氧纳米复合材料

由于聚合物纳米复合材料的剥离和分散存在不可克服的困难，开发可用于改善聚合物介电和热性能的低负载分数纳米级增强材料仍然是一个挑战。在这里，我们通过简便的原位合成将面条状氮化硼纳米带 (BNNR) 与环氧树脂 (EP) 结合在一起。BNNRs表面的羟基和氨基不仅可以提高分散性，还可以通过原位开环反应与BNNRs形成EP。研究了不同BNNRs含量的BNNRs/EP纳米复合材料的热行为、介电性能和热导率。在 1 wt% 的极低 BNNR 负载率下，纳米复合材料的热导率增加了 48%，这归因于BNNRs和EP强集成形成的长连续热传导路径。此外，电击穿强度从 95.58 提高到 159.17 kV·mm^-1随着 BNNRs 含量的增加，而纳米复合材料保持了可接受的介电性能。结果表明，BNNRs 具有作为介电聚合物新型纳米填料的潜力。