Polypyrrole stretchable actuators

Here, we report a simple way to prepare stretchable polypyrrole (PPy)-based actuator materials that can be operated over a wide dynamic strain range and generate useable actuation displacements and pressures. The stretchable actuators were prepared as a laminated composite of PPy and a gold-coated roughened rubber sheet. By manipulating the corrugated surface of the rubber substrate, the stretchability of PPy was greatly improved. Gold-coated rubbers could be stretched to 30% without significant change in electrical resistance. The corrugated PPy/gold/rubber laminates successfully showed ∼1% of actuation strain even when prestretched to 24%. The actuation strains were smaller than for similar free-standing PPy films and a detailed analysis of the effects of corrugation and of the rubber substrate are presented to predict actuation strain under various prestretch strains. © 2012 Wiley Periodicals, Inc.