Highly Thermally Conductive Yet Electrically Insulating Polymer/Boron Nitride Nanosheets Nanocomposite Films for Improved Thermal Management Capability
Highly Thermally Conductive Yet Electrically Insulating Polymer/Boron Nitride Nanosheets Nanocomposite Films for Improved Thermal Management Capability
复制标题
高导热且电绝缘的聚合物/氮化硼纳米片纳米复合薄膜可提高热管理能力
DOI：
10.1021/acsnano.8b06290
复制
发表时间：
2019-01-01
期刊：
影响因子：
17.1
通讯作者：
Jiang, Pingkai
中科院分区：
文献类型：
--
作者：
Chen, Jin;Huang, Xingyi;Jiang, Pingkai
现代电气系统和电子设备的热管理应用迫切需要导热且电绝缘的聚合物复合材料，因为它们具有多功能性且易于加工。然而，聚合物复合材料导热系数的增强通常是以损失轻质、恶化柔韧性和电绝缘性为代价的。在这里，我们报道了含有定向氮化硼纳米片（BNNS）的先进聚合物纳米复合材料，它同时表现出高导热性增强、优异的电绝缘性和出色的柔韧性。这些纳米复合材料薄膜可以通过静电纺丝聚合物/BNNS纳米复合纤维、垂直折叠静电纺丝纳米复合纤维并随后压制来轻松构建。纳米复合材料薄膜表现出与厚度相关的面内热导率，在含有 33 wt% BNNS 的 18 pm 厚的纳米复合材料薄膜中，热导率可以达到 16.3 W/(m.K.)。此外，与原始聚合物相比，纳米复合薄膜具有优异的电绝缘性能，例如降低介电损耗、增加电阻率和增强击穿强度。纳米复合薄膜强大的热管理能力在开关电源中得到了体现，这表明了高面内导热系数在高功率密度电子器件热管理中的重要性。
Thermally conductive yet electrically insulating polymer composites are urgently required for thermal management applications of modern electrical systems and electronic devices because of their multifunctionality and ease of processing. However, the thermal conductivity enhancement of polymer composites is usually at the price of the loss of lightweight, the deterioration of flexibility, and electrical insulation. Here we report advanced polymer nanocomposites containing orientated boron nitride nano sheets (BNNSs), which simultaneously exhibit high thermal conductivity enhancement, excellent electrical insulation, and outstanding flexibility. These nanocomposite films can be easily constructed by electrospinning polymer/BNNSs nanocomposite fibers, vertically folding the electrospun nanocomposite fibers and the subsequent pressing. The nanocomposite films exhibit thickness-dependent in-plane thermal conductivity, which can reach 16.3 W/(m.K.) in the 18 pm thick nanocomposite film with 33 wt % BNNSs. In addition, the nanocomposite films have superior electrically insulating properties compared with the pristine polymer, such as reduced dielectric loss, increased electrical resistivity, and enhanced breakdown strength. The strong thermal management capability of the nanocomposite film was demonstrated in switching power supply, which showed the importance of high in-plane thermal conductivity in thermal management of high-power density electronic devices.