软材料受刺激会发生变形，该变形会引起相应的功能，这种材料称为活性软材料（softactivematerial，SAM）．本综述主要讨论介电高弹聚合物这一类活性软材料．当介电高弹聚合物薄膜受到厚度方向的电压作用时，薄膜厚度减小同时面积增大，可导致超过100％的应变．介电高弹聚合物作为转换器被广泛应用，包括柔性机器人、智能光学器件、盲文显示屏、发电机等．本文综述了建立在连续介质力学和热力学框架内的、并且基于分子理论描述和经验观测的介电高弹聚合物理论．该理论耦合了大变形和电势，描述了非线性和非平衡行为，如力电失稳和黏弹性．采用该理论能够通过有限元方法模拟实际构型的转换器，计算力电能量转换的效率，给出电致大变形的可行途径．该理论有助于材料和器件设计．%In response to a stimulus, a soft material deforms, and the deformation provides a function. We call such a material a soft active material （SAM）. This review focuses on one class of soft active materials： dielectric elastomers. When a membrane of a dielectric elastomer is subject to a voltage through its thickness, the membrane reduces thickness and expands area, possibly straining over 100%. The dielectric elastomers are being developed as transducers for broad applications, including soft robots, adaptive optics, Braille displays, and electric generators. This paper reviews the theory of dielectric elastomers, developed within continuum mechanics and thermodynamics, and motivated by molecular pictures and empirical observations. The theory couples large deformation with electric potential, and describes nonlinear and nonequilibrium behaviors, such as eleetromeehanical instability and viscoelasticity. The theory enables the finite element method to simulate transducers of realistic configurations, predicts the efficiency of electromechanieai energy conversion, and sug- gests alternative routes to achieve giant voltage-induced deformation. It is hoped that the theory will aid in the creation of relevant materials and devices.
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