Bilayer microactuators of gold and polypyrrole doped with dodecylbenzene sulfonate, PPy(DBS), are characterized with respect to their response times and the influence of operation temperature. These parameters are needed for biomedical applications such as microvalves. To fully open and close the valves, the bilayer hinges must be able to rotate within a few seconds at body temperature. Bilayers were subjected to potential steps to switch the PPy between the oxidized and reduced states. Actuation was viewed through an optical microscope and recorded by a digital camera. The velocity profiles during reduction and oxidation follow the same trends. Two different phases of actuation can be identified. In the first phase there is rapid movement, and in the second phase the velocities slowly decrease until the position reaches steady-state. In order to investigate the effects of elevated temperature on the actuators, the operation temperature was varied stepwise from 25 °C to 55 °C. The curvature increased irreversibly by up to 45% at elevated temperatures, and the output force dropped.
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