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Application of conducting polymers has been growing widely in different fields such as batteries, solar cells, capacitors
and actuators. Mechanical properties of conducting polymers like flexibility, high power to mass ratio and high active
strain make them potentially applicable to robotic and automation industries. Obviously, a dynamic model of the
actuation phenomenon in conducting polymers is needed to study its controllability and also to optimize the mechanical
performance. De Rossi and colleagues suggest treating the mechanical behaviour of conducting polymers separately
from the viscoelastic structural model and electrochemical actuation[1]. But it has been observed that the effects of
electrochemical actuation and diffusion of ions on the viscoelastic coefficients cannot be neglected in some conducting
polymer actuators, as shown in[1]. In this paper, we present the effects of cyclic voltammetry actuation on shear modulus
of polypyrrole in propylene carbonate and EMI.TSFI as measured by an electrochemical Quartz Crystal Microbalance
(eQCM). The QCM consists basically of an AT-cut piezoelectric quartz crystal disc with metallic electrode films
deposited on its faces. One face is exposed to the active medium. A driver circuit applies an AC signal to the electrodes,
causing the crystal to oscillate in a shear mode, at a given resonance frequency. QCM has been routinely used for the
determination of mass changes. Measured resonance frequency shifts are converted into mass changes by the wellknown
Sauerbrey's equation. In this paper, we correlate the admittance output of QCM to the real shear modulus of
polypyrrole. Then the results of the correlation which contains mechanical data are presented during actuation using two
different types of electrolyte.
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