Electrothermal actuators (ETAs) are novel active materials that can generate different kinds of motions by thermal
expansion induced from Joule heating. The degree of expansion, which influences the deformation and response force, is
determined by the coefficient of thermal expansion (CTE) of the material. In order for the material to be activated, it is
necessary to create conductive network for Joule heating to take place. As a result, one of the most common methods for
creating ETAs is to insert high electrical and thermal conductive filler into the matrix, which allows for fast and uniform
heat distribution though out the material, thus initiate the actuation. In this study, we present the characterization results
of newly developed ETA composites that has ultra-low activation voltage requirement (9V). To create the novel ETA
composites, polydimethylsiloxane (PDMS) is coated to conductive networks which are constructed from high electrical
conductive fillers such as carbon nanotubes. The actuation performance of the novel ETA composites is characterized in
terms of the conductive network distribution, CTE, heat capacity, change in thermal gradient, and its actuation
behaviour.
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