Fabrication and performance of ionic polymer-metal composites for biomimetic applications

Abstract

Ionic Polymer-Metal Composites (IPMCs) consisting of ionic polymer membrane sandwiched between platinum and copper (Cu-Pt) electrodes have been synthesized via electroless plating and electroplating. The tip displacement of Cu-Pt coated IPMC reached about 10.7 mm when a sinusoidal potential of 3V, 0.6Hz was applied through the membrane. The surface roughness of Pt coated IPMC, Cu-Pt coated IPMC and Cu-Pt coated IPMC after bending deformation tests were 1.21, 0.77 and 0.71 μm respectively, indicating that Cu electrode could reduce surface roughness. It was also found that a new generated Cu layer healed the cracks of Pt electrode, was formed through using voltage polarity. Butyl rubber and polydimethysiloxane (PDMS) were employed to encapsulate Cu-Pt coated IPMC to prevent Cu electrode from oxidation. The output deformation of packaged Cu-Pt coated IPMCs were stable under various amplitude of potential. The deflection of Cu-Pt coated IPMCs kept in air for 3, 7, 15 and 22 days respectively had no significant changes and were all about 10.1 mm by applying the potential of 3V, 0.6Hz, revealing that Cu electrode is durable and Cu-Pt coated IPMCs exhibit remarkable promise as biomimetic actuators.