Low temperature characteristics of ionic polymer-metal composite actuators

Presented here is a description of ionic polymer-metal composites (IPMCs) as an attractive solution for cold operation actuators. This is because of their capability for actuation with relatively low electric fields (similar to10kV/m), durability and capability of operating within the subzero regime T < 0degreesC. The building block material of IPMCs experiences phase changes within the base polymeric material that results in an alteration of the performance of the material in terms of actuator performance. An experimental apparatus is constructed in order to have a controlled temperature environment in which to analyze the material. The overall temperature within the reservoir, the temperature on the IPMC surface electrodes, the conductivity of the membrane and the blocking force were all measured. The phase changes inherent at these low temperatures are investigated further by means of differential scanning calorimeter to obtain the phase change temperatures and characteristics. The results are presented and interpreted to show that there is definite promise for these low temperature polymeric actuators to operate in practical applications. (C) 2004 Elsevier B.V. All rights reserved.