Electrode interface polarization formation in dielectric elastomer actuators

Dielectric elastomer actuators (DEAs) are a class of electrostatic actuators that have promising applications in fields like sensors, soft-robotics, microfluidics, and energy harvesting. The crucial points in the working principle of DEA are the application of high electric field and the use of compliant electrodes. These electrodes are typically composed of a mixture of a soft polymer base filled with highly conductive particles. In this work, we show that the charged impurities, possibly present in the electrodes composite, in combination with a high electric field can cause the formation of polarization interface layers between the electrodes and the inner dielectric. These layers can, in the long term, diminish the actuation performance of the DEA.