面向机械能向电能转换的介电弹性体复合材料的设计与制备

Dielectric elastomer generator (DEG) that can transform mechanical energy in natural environment into electric energy is a promising device to produce renewable energy. The key to prepare high performance DEG is to fabricate a dielectric elastomer with high dielectric constant, low elastic modulus, low dielectric loss, and large electrical breakdown strength. Elastomer has large deformation, but its low dielectric constant limits improving the generated energy and machine-electricity conversion efficiency of DEG. In this work, dielectric nano-particles with good compatibility, high dielectric constant, and low dielectric loss, will be synthesized and added into elastomer matrix to form dielectric elastomer composites. The effect of interfacial characterization of dielectric particles, crosslink density of the elastomer matrix, and plasticizer content et al on intrinsic properties (mechanical properties, viscoelasticity, dielectric properties, insulating properties), energy harvesting properties (generated energy, machine-electricity conversion efficiency, energy density), fatigue properties (service life), and stability of energy harvesting properties of composites will be systematically studied, and the relationship among raw materials selection, preparation condition, and generating properties of dielectric elastomer composites will be built. These will provide theoretical foundation and technique method for designing and practical application of high machine-electricity conversion efficiency DEG, and a new approach for developing new energy.

介电弹性体发电机(DEG)能将自然环境中的多种机械能转变为电能，可望成为一种再生能源新方式。发展性能可靠DEG的关键在于制备具有高介电常数、低弹性模量、低介电损耗、高电击穿强度的介电弹性体材料。弹性体具有优越的大变形，但介电常数较低，限制了DEG的发电量和机-电转换效率的提高。本项目将设计一种具有良好相容性、高介电常数、低介电损耗的介电纳米粒子，填充至弹性体基体中制备介电弹性体复合材料，以满足上述要求。系统研究介电纳米粒子的界面特性、弹性体基体的交联密度、增塑剂用量等因素对介电弹性体复合材料的本征性能(力学性能、粘弹性能、介电性能、绝缘性能)、发电性能(发电量、机-电转换效率、能量密度)、疲劳性能(使用寿命)及发电性能稳定性的影响。建立介电弹性体复合材料的原材料选择、制备工艺与发电性能关系，为高机-电转换效率DEG的设计制备及实际应用提供理论基础和方法，有望为新能源的开发提供新的途径。

介电弹性体是一种具有大形变、快响应、轻质量、高转换效率及高能量密度的电活性聚合物，可应用于微型驱动器和发电机上，在智能机器人、电子器件、人工肌肉、航空航天以及发电机等领域已具有一定的应用。但是介电弹性体材料的介电常数普遍较低，限制了其进一步应用。本项目工作主要集中在提高介电弹性体材料的介电常数上，以提高介电弹性体发电机的发电性能和介电弹性体驱动器的电致形变性能。具体研究内容包括：(1)制备具有高发电量和高机-电转换效率的介电弹性体复合材料;(2)提出介电纳米颗粒表面改性的新方法，制备高驱动应变的介电弹性体复合材料;(3)通过调控分子间作用力和填料网络结构，制备具有高电驱动敏感因子的介电弹性体复合材料。通过本项目的研究，建立了介电弹性体复合材料微观结构及其本征性能与电机性能的关系，为高性能介电弹性体复合材料的设计制备及实际应用提供理论基础和方法，具有重要的学术价值和理论意义。