Electrical properties and electromechanical modeling of plasticized PVC gel actuators

We studied the detailed electrochemical and electromechanical properties of a polyvinyl chloride (PVC) gel with dibutyladipate (DBA) as a plasticizer and developed an electromechanical model based on the electrochemical data. We evaluated the electric deformation of the PVC gel by the bending displacement response of the PVC gel strip when a square-wave voltage is applied. For every electrode, the bending responses were to the anode side and increased with the applied voltage. The bending response of the PVC gel is considered to be due to the electric creep movement on the anode surface. We checked this result by optical microscopy. We studied the electrochemical impedance measurements of the PVC gel under bias voltages and the voltage-current and voltage-displacement measurements in response to a triangle-wave voltage. Based on the above electromechanical and electrochemical experimental results, we developed a deformation model of the PVC gel where the electric bending response is basically due to the electrochemical formation of the solvent-rich layer and its deformation from the Maxwell stress. We estimated the displacements with applied voltages of 200 and 1000 V, and the model results were in good agreement with the experimental results despite the rough estimation.