具有优异电驱动特性的介电弹性体设计、制备及其性能调控机制

Dielectric elastomer (DE) is a kind of novel functional material, which can deform under the external electric field and capture external mechanical energy. Thus it can realize the mutual transformation of mechanical energy and electric energy, and can be used to develop new devices for the conversion of different forms of energy. The application of dielectric elastomers is limited by the small actuation strain of existing dielectric elastomers and high electric fields for large actuation strain. Thus, in this project, the advanced acrylic dielectric elastomer with significant actuation strain at low electric fields will be investigated. According to the actuation mechanism of the dielectric elastomer, the electroactuation performance of the dielectric elastomer is affected by the combination of mechanical properties and dielectric properties. Therefore, in this project we intends to achieve the controllability of its electroactuation performance by synergistically regulating the mechanical properties and dielectric properties of dielectric elastomers. Specifically, we will prepare new dielectric elastomers with adjustable monomer types and ratios and controllable structures through solution polymerization\photocuring etc, and identify the key factors affecting the actuated strain and electroactuation characteristics of dielectric elastomer from Multi-scale structure of dielectric elastomers. We will clarify the relationship between dielectric elastomer composition, structure and performance, and reveal the physical mechanism for achieving significant actuated strain of dielectric elastomers in low-drive electric fields and the design and synthesis of these materials. This work will provide the basic theory and novel materials for the new type of dielectric elastomer and its research and application in the field of actuators.

介电弹性体是具有电致驱动和俘获外部机械能实现电能与机械能相互转换的新型功能介质材料，可用于不同形式能源相互转换的新一代器件研制。现有的介电弹性体材料的驱动形变量比较小或者在很高的驱动电场下实现大驱动形变限制了介电弹性体的广泛应用，因此本项目提出研究在低驱动电场时具有显著驱动应变的新型介电弹性体。根据介电弹性体的驱动机理可知，介电弹性体的电驱动性能受其力学性能和介电性能的综合影响，因此本项目拟通过协同调控介电弹性体的力学性能和介电性能来实现其电驱动性能的可控性，具体为：通过溶液聚合、光聚合等方法制备单体种类和比例可调，以及结构可控的新型丙烯酸酯介电弹性体，从多尺度结构查明影响介电弹性体形变和电驱动特性的关键因素，理清介电弹性体组成、结构与性能的关系，揭示在低驱动电场时实现介电弹性体具有显著驱动应变的物理机制及其材料结构设计与合成，为新型介电弹性体及其驱动器领域研究及应用提供基础理论和新材料。

介电弹性体是一种新型电活性聚合物，在外加电场刺激下介电弹性体薄膜可改变形状或体积将电能直接转换为机械能，然而高驱动电场严重限制了介电弹性体的广泛应用。本项目以在低驱动电场时具有显著驱动应变特性的新型介电弹性体材料为研究对象，主要通过调控交联剂、单体种类及含量，利用紫外光固化法制备具有不同微结构的丙烯酸酯介电弹性体，然后基于全面的结构表征、性能测试，厘清了材料结构与性能之间的关系，并通过构建不同结构的柔性驱动器探索介电弹性体在该领域的应用前景。.本项目的主要研究内容：1，首先以聚氨酯二丙烯酸酯作为交联剂，丙烯酸正丁酯作为软单体，通过调控二者比例制备一组高性能介电弹性体，并基于该材料构建了类鱼尾的驱动器件；2，在工作1的基础上，通过引入线性大分子增塑剂制备全有机丙烯酸酯介电弹性体，并厘清了材料的构效关系，实现较低电场形变；3，同时基于工作1，通过引入功能单体制备了具有高击穿强度大驱动形变的介电弹性体，并构建了具有大输出力、输出位移的卷轴驱动器。以上工作为低电场高驱动形变的介电弹性体的构建及其在柔性驱动器领域的应用奠定了坚实的基础。项目研究已达到预期目标，共发表基金标记的论文5篇，包括ACS Applied polymer science, ACS Applied material&interface, IET Nanodielectrics等。