Topological-Structure Modulated Polymer Nanocomposites Exhibiting Highly Enhanced Dielectric Strength and Energy Density
Topological-Structure Modulated Polymer Nanocomposites Exhibiting Highly Enhanced Dielectric Strength and Energy Density
复制标题
拓扑结构调制聚合物纳米复合材料具有高度增强的介电强度和能量密度
DOI：
10.1002/adfm.201303684
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发表时间：
2014-06-01
影响因子：
19
通讯作者：
Nan, Ce-Wen
中科院分区：
文献类型：
--
作者：
Hu, Penghao;Shen, Yang;Nan, Ce-Wen
具有高电能密度和低介电损耗的介电材料在现代电子和电力系统中的许多应用中是至关重要的。一种有机-无机0-3纳米复合材料，其中纳米颗粒（0维）嵌入在三维连接的聚合物基体中，具有潜在的联合收割机结合的高击穿强度和低介电损耗的聚合物与陶瓷填料的高介电常数，代表一种有前途的方法，以实现高能量密度。然而，迄今为止所研究的复合材料的一个显著缺点是，复合材料的介电常数的增加是以击穿强度为代价的，限制了能量密度和介电可靠性。在这项研究中，通过将传统的0-3纳米复合材料的方法扩展到结合了组成层的互补特性的多层结构，可以实现比聚合物基体更大的介电位移和更高的击穿场。在典型的3层结构中，例如，引入具有较高击穿强度的中心纳米复合材料层以显著提高多层结构复合膜的总体击穿强度，然后填充有大量高介电常数纳米填料的外部复合材料层可以被极化至更高的电场，从而增强电位移。其结果是，拓扑结构调制的纳米复合材料，具有最佳定制的纳米形态和复合结构，产生放电能量密度为10 J/cm 3，介电击穿强度为450 kV mm-1，远高于那些报道的所有早期研究的纳米复合材料。
Dielectric materials with high electric energy densities and low dielectric losses are of critical importance in a number of applications in modern electronic and electrical power systems. An organic-inorganic 0-3 nanocomposite, in which nanoparticles (0-dimensional) are embedded in a 3-dimensionally connected polymer matrix, has the potential to combine the high breakdown strength and low dielectric loss of the polymer with the high dielectric constant of the ceramic fillers, representing a promising approach to realize high energy densities. However, one significant drawback of the composites explored up to now is that the increased dielectric constant of the composites is at the expense of the breakdown strength, limiting the energy density and dielectric reliability. In this study, by expanding the traditional 0-3 nanocomposite approach to a multilayered structure which combines the complementary properties of the constituent layers, one can realize both greater dielectric displacement and a higher breakdown field than that of the polymer matrix. In a typical 3-layer structure, for example, a central nanocomposite layer of higher breakdown strength is introduced to substantially improve the overall breakdown strength of the multilayer-structured composite film, and the outer composite layers filled with large amount of high dielectric constant nanofillers can then be polarized up to higher electric fields, hence enhancing the electric displacement. As a result, the topological-structure modulated nanocomposites, with an optimally tailored nanomorphology and composite structure, yield a discharged energy density of 10 J/cm3 with a dielectric breakdown strength of 450 kV mm-1, much higher than those reported from all earlier studies of nanocomposites.