Wang Xiongwei, Wu Peiyi
State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Chemistry, Chemical Engineering and Biotechnology, Center for Advanced Low-Dimension Materials , Donghua University , Shanghai 201620 , P. R. China.
State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science , Fudan University , Shanghai 200433 , P. R. China.
ACS Appl Mater Interfaces. 2019 Aug 14;11(32):28943-28952. doi: 10.1021/acsami.9b09398. Epub 2019 Aug 2.
Construction of a three-dimensional (3D) vertically aligned filler network in a polymer matrix has been believed to be an effective method to attain a large through-plane thermal conductivity enhancement at relatively low filler loading. However, it is still a challenge to construct a vertically aligned filler network composed of many long-range continuous pore channels in a polymer matrix for the high-flux heat-conduction. To address this problem, herein, nanofibrillated cellulose (NFCs) assisted unidirectional freeze-drying of a boron nitride nanosheets (BNNSs) slurry was used to prepare a novel epoxy composite containing a 3D vertically aligned BNNS network with long-range continuous pore channels. The vertically aligned and nacre-mimetic channels make the composite possess a high through-plane thermal conductivity of 1.56 W m K at an extremely low BNNSs loading of 4.4 vol %, and a significant thermal conductivity enhancement efficiency of 167.3 per 1 vol % filler. Therefore, we think this work is expected to give a significant insight into the preparation of polymer composite with high heat-conduction efficiency to address the heat dissipation of modern electronics.
在聚合物基体中构建三维（3D）垂直排列的填料网络被认为是一种在相对较低填料负载量下实现大幅提高面内热导率的有效方法。然而，在聚合物基体中构建由许多长程连续孔隙通道组成的垂直排列填料网络以实现高通量热传导仍然是一个挑战。为了解决这个问题，本文采用纳米纤化纤维素（NFCs）辅助的氮化硼纳米片（BNNSs）浆料单向冷冻干燥法制备了一种新型环氧复合材料，该复合材料含有具有长程连续孔隙通道的3D垂直排列BNNS网络。垂直排列且仿珍珠层的通道使该复合材料在极低的4.4体积% BNNSs负载量下具有1.56 W m⁻¹ K⁻¹的高面内热导率，以及每1体积%填料167.3的显著热导率增强效率。因此，我们认为这项工作有望为制备具有高导热效率的聚合物复合材料以解决现代电子产品散热问题提供重要见解。
