Relationship between electrode polarization and electrical actuation of dielectric PVC gel actuators

Abstract

Dielectric properties are considered to be one of the most important properties for the effectiveness of electrically induced actuation of PVC gel actuators. To clarify the actuation mechanism from the molecular motion and polarization of PVC gel actuators in an electric field, the frequency dependent dielectric properties have been investigated by AC impedance spectroscopy. The dielectric constant and dielectric loss of the PVC gel greatly increased at low frequencies due to electrode polarization and dipole orientation. The electrode polarization for negative charge accumulation in the PVC gel was confirmed by space charge measurement. By blocking the electrode with a polytetrafluoroethylene (PTFE) sheet between the PVC gel and the cathode, there was no actuation or electrode polarization. This indicates that charge injection from the cathode and dipole orientation are important factors for the actuation of PVC gels, and electrode polarization is closely related to the actuation of PVC gels in an electric field.