复层核壳结构颗粒调控介电弹性体复合材料功能特性的基础研究

Due to their excellent electroactive properties and applicable potential in multi-condition, dielectric elastomer composites have been paid a widely attention and deeply studied. However, how to improve both the electroactive pressure and actuation strain of materials synchronously and significantly under a relatively low electrical field, which requires the further mechanism investigation and effective materials design. This research project will base on the successive dependence among “Micro-structure → Macro-performance → Functional application”, with the aid of the reasonable construction of multi-layer core-shell architectures with a high polarizing efficiency as the functional fillers. Most importantly, this project will mainly concentrate on studying the regulating dependency of the typical structural parameters of multi-layer core-shell architectures to the functional properties of dielectric elastomer composites. In detailed, firstly, through constructing and characterizing the shells layer-by-layer, the multi-layer core-shell architecture will be constructed controllably, moreover, the relationship between processing parameters of surface coating processes and structural characteristics of multi-layer core-shell architectures will be also established. Secondly, by means of analyzing the dependent relationship between structural characteristics of multi-layer core-shell architectures and the dielectric performances of composites, the regulating mechanism of the additional core-shell interface to the space charge interfacial polarization will be revealed. Last but not least, the synergetic influence of structural characteristics of multi-layer core-shell architectures to the flexibility and electroactive performance of dielectric elastomer composites will be quantitatively evaluated and illuminated. In addition, design and fabricate the advanced dielectric elastomer actuators with optimized electroactive performance under a low electrical field will be another important issue in this project. The project will therefore not only provide reasonable strategies for the mechanism study of dielectric performance of composites in micro-scale, but also promote the further performance improvement and application expansion of advanced dielectric elastomers.

介电弹性体复合材料以其优异的电响应特性和多环境应用潜力，受到了广泛关注与深入研究。但如何实现材料在低电场下驱动力与形变的显著同步提升，目前仍缺乏系统的机理探究和有效的材料设计。本研究提出以“微观结构→宏观性能→功能应用”逐级靶向调控为研究主线，按照合理构筑高极化耦合效率的复层核壳结构填充单元的研究思路，开展复层核壳结构对介电弹性体复合材料功能特性的调控研究。通过协同逐层构筑与逐层形貌结构表征，实现复层核壳结构颗粒的可控构筑，建立包覆工艺参数与核壳结构形貌特征的影响规律；分析核壳结构特征与复合材料宏观介电性能的依赖性，揭示附加核壳界面对微观空间电荷界面极化的调控机制；定量评价并阐明复层核壳结构与介电弹性体柔性、电致驱动特性的协同耦合关系，实现低电场下介电弹性体的显著驱动特性。本项目不仅为复合材料介电性能的调控研究提供新思路，也将推动新型介电弹性体的机理深化、性能提升与应用拓展。

本项目对多种纳米核壳结构的设计构建及其作为高极化功能填料对复合介电弹性体的电致驱动特性进行了研究。项目首先探索了针对不同形貌维度和本征特性核材料的介电常数递减、递增以及一核多壳等特殊核壳结构的构建，探明了壳层构建工艺不同参数对壳层形貌结构的调控作用。在此基础上，利用溶液/机械共混和加压交联法设计制备出了不同核壳结构改性的介电弹性复合材料，通过对所得复合介电弹性体的介电、力学以及电致驱动等功能特性进行表征分析，总结归纳了附加核壳界面对体系的微观极化影响以及核壳结构对复合体系的柔性保持，对复合介电弹性体电活性的协同耦合调控作用。本项目实施期间，共发表SCI研究论文6篇，申请国家发明专利1项，培养研究生5名，并多次参加国内外学术交流与讨论。本项目的研究成果，有效地优化了复合介电弹性体在低电场下的电致驱动特性，也对新型介电弹性体的机理完善和应用拓展提供了一定促进作用。