聚合物基复合材料的梯度界面耦合效应调控及高温储能稳定性研究

Dielectric capacitors, with ultrafast charge-discharge rate and high power energy density, have the potential to be widely applied in the modern industry and military power systems. However, the capacitors of polymer-based dielectric materials have poor thermal stability, and it is difficult to get stable performance at relative the high temperature. Especially, with the increasing temperature at higher applied electric field the energy storage density and discharge efficiency of capacitors would drop sharply so that causing breakdown in the working process, which can not meet the commercial application requirements. This proposal focuses on the high-temperature stability performance of energy storage density in polymer nanocomposites. We will design the special inorganic fillers microstructures to form gradient interface in the nanocomposites so as to improve their high-temperature stability performance. Subsequently, we will further explore the regulation mechanism of gradient interface towards multiple coupling effects of the mechanical, electrical and thermal properties through constructing the theoretical model among the microstructure, gradient interface coupling effect and high-temperature stability of energy storage performance. According to the studies of gradient interface coupling effects and regulation mechanism, the dielectric composites with simultaneously large energy storage density, high efficiency, and stable working performance at high-temperature will be designed and prepared. This proposal could serve as an important guide for the material preparation theoretical studies, and energy storage performance in dielectric capacitors. And it also could greatly benefit the lightweight and energy-efficient design of high-temperature dielectric capacitors.

电介质电容器具有充放电速率快和功率密度高，在国防及民用等高科技领域有广泛的应用及前景。以聚合物电介质材料为主体的电容器热稳定性较差，且难以在高温环境下稳定工作。尤其在高电场下，温度升高使储能密度及放电效率急剧下降甚至失效，无法满足应用需求。本项目旨在突破聚合物基复合材料高温储能稳定特性，拟通过无机填料微结构的设计方法制备形成梯度变化界面的复合材料来提高其高温储能稳定特性；针对复合材料的梯度界面耦合效应，构建“微结构-梯度界面耦合效应-极化行为-击穿场强-高温储能稳定特性”理论模型，深入探索其力、电和热因素独立和协同耦合效应对高温储能稳定特性的调控机制；基于梯度界面耦合效应调控机制研究，设计并制备兼具高储能密度、高效率且能在高温下稳定工作的聚合物基复合材料。该研究将为耐高温聚合物基储能材料的制备、理论研究和性能提升提供重要指导，对微型化、轻量化的高温储能电容器发展具有重要意义。

聚合物薄膜电容器作为储能及脉冲系统的核心部件，在新能源汽车工业、航空电子及油气勘探等领域具有广泛的战略需求。目前，传统聚合物介质材料在高温、强电场条件下连续工作时产生大量焦耳热，使薄膜电容器因热失稳而发生故障，成为制约高温电子器件和设备发展的技术瓶颈。项目提出研究聚合物基复合材料，以期待通过界面效应调控融合二者优势实现高性能耐高温复合材料。目前，现有研究重点主要关注于界面处电耦合性能对复合材料高温储能性能的影响，但聚合物基复合材料涉及无机和有机界面处的力、电及热性能的独立效应以及协同耦合效应，深入研究界面对无机和有机材料力、电、热因素的耦合作用也至关重要。针对复合材料高温储能性能中力、电、热因素间的特殊联系，项目突破了复合材料研究中仅关注界面电极化耦合效应的局限，深入研究了聚合物复合材料中的界面对复合材料内各组分力、热和电性能进行“融合”与“沟通”的本质，进一步分析了材料的微观结构变化对聚合物复合材料界面效应调控的规律，并研究了聚合物复合材料“微结构-界面耦合效应-极化行为-击穿场强-高温储能稳定特性”间的理论关系模型；在此基础上，通过无机填料形貌（零维、一维阵列、二维核壳结构等）变化调控了复合材料的界面特性以及高温储能稳定特性，并设计和制备了特定微结构的复合材料（单层、叠成、三明治结构）；通过研究材料的制备工艺、复合材料的微观结构以及力、电、热多场耦合关系等，最终获得了高性能的耐高温聚合物基复合材料。