有机薄膜电容器用高耐热聚芳醚腈基纳米复合材料性能研究

Recently, the demand for light-weight capacitors with high energy density in electrical fields is booming. The essential material of capacitors is dielectrics with high dielectric constant (high-k). So, the key to fabricate capacitors with high energy density is to develop new materials with high-k. Compared to traditional ceramics in ceramic dielectrics, polymer based composites possess lighter weight, however, the dielectric constant is much lower. The ideal way is to develop polymer/ceramics composites, in order to obtain dielectrics with comprehensive advantages, i.e., high-k, light-weight and easy-to-process, etc. In this project, a series of poly(arylene ether nitriles) with different structures and adjustable molecular weight by changing the monomers with symmetrical structure, the molar ratio and the reaction conditions. The obtained product possesses good thermal property and high crystallinity. Then, the surface of high-k inorganic nanofillers is modified by coupling agent, working as a “molecular bridge” between polymer matrix and the nanofillers. Finally, high-k polymer based composites are prepared via sol-dispersion method combined with ultrasonic dispersion. The dielectric strength of the polymer based composites is enhanced by biaxial hot-stretching technology. As a result, the energy storage density of poly(arylene ether nitriles) based composites is synergistically enhanced combining the advantages of high dielectric constant and high dielectric strength.

近年来，电子电器领域对轻量化以及高储能密度电容器的需求日益提高。电容器的基本材料为高介电材料，所以开发新型高介电材料是制备高储能密度电容器的关键。和普通陶瓷电容器里的高介电陶瓷相比，聚合物基电介质拥有较低的质量比，但是介电常数往往较低。理想的方式是开发高介电聚合物-陶瓷复合材料，得到韧性好、易加工、轻量化等综合性能优异的高介电电介质。本项目拟采用分子结构对称的单体为原料，通过改变单体种类、摩尔比和反应条件合成出一系列不同分子结构和分子量可以调控聚芳醚腈，该聚芳醚腈具有高耐热性与高结晶度。利用偶联剂对高介电无机纳米填充剂进行表面修饰，在无机填料与聚合物基体之间形成“分子桥”的作用。采用溶胶分散法，制备高介电聚芳醚腈基纳米复合材料。采用“双轴热拉伸”工艺，进一步增强复合材料薄膜的击穿强度。结合高介电常数和高击穿强度两者优势，所得复合材料的储能密度可以得到协同增强。

近年来，电子电器领域对轻量化以及高储能密度电容器的需求日益提高。电容器的基本材料为高介电材料，所以开发新型高介电材料是制备高储能密度电容器的关键。我们首先合成了5种不同结构单元构成的聚芳醚腈基体，联苯二酚型聚芳醚腈、间苯二酚型聚芳醚腈、对苯二酚型聚芳醚腈、对苯-酚酞型聚芳醚腈和酚酞啉型聚芳醚腈，并且对其综合介电性能进行了详细表征，最终选取了介电性能比较理想的一种聚芳醚腈。然后分别采用聚多巴胺和硅烷偶联剂对高介电纳米填料纳米填料表面有机化改性处理，改善纳米粒子和聚合物之间的相容性问题。接下来，我们分别采用聚多巴胺和硅烷偶联剂改性的纳米钛酸钡与聚芳醚腈复合制备了复合材料。接下里奥我们通过改变填料的粒径与含量的质量分数，择优选取了填料含量和粒径比较合理的复合材料进行介电常数，介电损耗，储能密度，密度，耐热性，充放电效率，充放电时间等相关测试！通过相关表征，我们找到了比较理想的表面改性剂和比较适度的填料的质量分数！此外，聚芳醚腈本身具备良好的耐辐照能力，因此，制备出的聚合物基复合材料有望获得比较好的辐照下的生存能力！