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Electromechanically active polymers (EAP) are considered a good actuator candidate for a variety of reasons, e.g. they
are soft, easy to miniaturize and operate without audible noise. The main structural component in EAPs is, as the name
states, a type of deformable polymer. As polymers are known to exhibit a distinct mechanical response, the nature of
polymer materials should never be neglected when characterizing and modeling the performance of EAP actuators.
Bucky-gel actuators are a subtype of EAPs where ion-containing polymer membrane acts as an electronically insulating
separator between two electrodes of carbon nanotubes and ionic liquid. In many occasions, the electrodes also contain
polymer for the purpose of binding it together. Therefore, mechanically speaking, bucky-gel actuators are composite
structures with layers of different mechanical nature. The viscoelastic response and the shape change property are
perhaps the most characteristic effects in polymers. These effects are known to have high dependence on factors such as
the type of polymer, the concentration of additives and the structural ratio of different layers. At the same time, most
reports about optimization of EAP actuators describe the alteration of electromechanical performance dependent on the
same factors. In this paper, the performance of bucky-gel actuators is measured as a function between the output force
and bending deflection. It is observed that effective stiffness of these actuators depends on the input voltage. This finding
is also supported by dynamic mechanical analysis which demonstrates that the viscoelastic response of bucky-gel
laminate depends on both frequency and temperature. Moreover, the dynamic mechanical analysis reveals that in the
range of standard operation temperatures, tested samples were in their glass transition region, which made it possible to
alter their shape by using mechanical fixing. The mechanical fixity above 90% was obtained when high-frequency input
signal was used to heat the bucky-gel sample.
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