Maximum actuation strain for dissipative dielectric elastomers with simultaneous effect of prestretch and temperature

Abstract

A dielectric elastomer can generate giant deformation by the voltage actuation, but the deformation is often hindered by the electromechanical instability and “snap‐through deformation,” which may lead to electrical breakdown. In this study, for the first time, the mathematical model is established for dissipative dielectric elastomers in the dynamic model with simultaneous effect of prestretch and temperature in order to achieve maximum actuation strain. The deformation of the dissipative dielectric elastomer: VHB 4905/4910 is investigated for the two simple actuation methods: constant and ramping voltage actuation, respectively. The best combined conditions of voltage and prestretch to obtain a large deformation at different operating temperatures are studied in detail. Under the best combined conditions, the influences of three factors: voltage, prestretch, and temperature on the maximum actuation strain are analyzed. This study should offer a great help in the design of dielectric elastomer actuators, and give the guidance to the accomplishment of the large deformation of dissipative dielectric elastomer actuators. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45850.

Theory analysis method for the effect of temperature and electrostrictive on the actuation stability of dielectric elastomers

“…Although most DE researches did not consider the temperature parameter, it affects also the elastic modulus and dielectric constant of DE (Jean-Mistral et al, 2010; Vu-Cong et al, 2013b). Deng et al (2018) studied the effect of constant and ramp voltage with the optimum temperature, pre-tension, and voltage combination that achieved the maximum driving strain. Sheng et al analyzed various failure modes and the stability of DE with a model of the temperature effect.…”

Improving the performance of dielectric-elastomer actuators at elevated operating temperatures by means of thermal softening

“…It was also reported that the natural frequency increases at lower temperatures (natural frequency at 273 K is 29.53 rad s −1 while that is 16.34 rad s −1 at 333 K) when tested under sinusoidal nominal electric fields. According to Deng et al [21], the maximum actuation strain enhances with the increase of the voltage but drops with the increase of prestretch and temperature in the area of the best combined conditions under the constant voltage stimulation. However, under the ramping voltage condition, the maximum actuation strain increases with the decrease of prestretch, ramping rate, and temperature within the best combined conditions areas.…”