Effects of water content on the actuation performance of ionic polymer-metal composites

This paper presents an experiment on the effects of water content on the actuation performance of ionic polymer-metal composites (IPMCs). Specifically, Nafion 117 sandwiched by platinum electrodes was actuated by AC voltage for 2 h. Because the water molecules in Nafion 117 evaporated into the air, the change of the actuation performance of IMPCs with decreasing water content was investigated. The actuation mechanism of IPMCs under different initial water contents with different applied voltages was also discussed. The largest deformation of IPMCs was obtained under a water content of ~ 70%. The displacement amplitude of IPMCs required 100-900 s to reach the maximum value under different applied voltages and initial water contents. A linear relation between the peak value of the current and the water content at 3 V_pp driving voltage has also been observed.