Zheng Xianghe, Zhou Jianyou
School of Science, Harbin Institute of Technology, Shenzhen 518055, China.
Polymers (Basel). 2023 Dec 29;16(1):113. doi: 10.3390/polym16010113.
Elastomers, as a typical category of soft dielectrics, have shown great potential for developing stretchable electronics and soft transducers. However, the performance of dielectric elastomers (DEs) is susceptible to the dielectric permittivity of the material, whether as insulators or actuators. On the other hand, experiments suggest that the material viscoelasticity significantly influences the dielectric permittivity of DEs. Based on the theory of finite-deformation viscoelasticity, this work adopts the Brillouin function to develop a modeling framework to examine the effect of material viscoelasticity on the dielectric permittivity for the first time. A comparison of the data fitting results between the models with and without consideration of the material viscoelasticity is presented. Simulation results also reveal that the viscous network of the elastomer exerts a mitigation effect on the decrease in the dielectric permittivity when the material is deformed. Furthermore, it is found that the loading rate is a key parameter that strongly affects the dielectric permittivity, mainly through the inelastic deformation.
作为一类典型的软电介质，弹性体在开发可拉伸电子器件和软传感器方面展现出了巨大潜力。然而，无论是作为绝缘体还是致动器，介电弹性体（DEs）的性能都易受材料介电常数的影响。另一方面，实验表明材料的粘弹性会显著影响DEs的介电常数。基于有限变形粘弹性理论，本研究首次采用布里渊函数建立了一个建模框架，以研究材料粘弹性对介电常数的影响。文中给出了考虑和不考虑材料粘弹性的模型之间数据拟合结果的比较。模拟结果还表明，当材料发生变形时，弹性体的粘性网络对介电常数的降低具有缓解作用。此外，研究发现加载速率是一个强烈影响介电常数的关键参数，主要是通过非弹性变形来实现的。
