Ionic polymer-metal composites (IPMCs) and ionic polymer-polymer composites (IP2Cs): Effects of electrode on mechanical, thermal and electromechanical behaviour

Electro-active polymers (EAPs) are soft polymers that develop mechanical strain if subjected to electrical stimuli or, on the contrary, produce voltages if mechanically deformed. Their discovery has led to take into account their possible use as sensor-actuator for both bio-mimetic applications and traditional robotics. Ionic polymer-metal composites (IPMCs) and ionic polymer-polymer composites (IP2Cs) belong to EAPs. Both of them are fabricated starting from an ionic polymer (typically Nafion®117) but while in IPMCs the electrode is based on a metal (Ag, Au or Pt), IP2Cs are all-organic devices: in fact a conducting polymer (e.g., poly(3,4-ethylendioxytiophene)-polystyrenesulfonate, PEDOT/PSS) is used as the electrode. In this work, a comparison has been done among the fabrication processes and the mechanical, thermal and electromechanical behaviour of IPMCs and IP2Cs. The objective is to investigate the influence of the kind of electrode on the final properties of the devices, taking, also, into account the effect of different solvents, used for realizing the actuation process (H2O or Ethylene Glycol). Reported results show that the performance of the obtained devices are function of manufacture parameters, the kind of electrode and solvent; consequently, taking into account the possible application, it is possible to choose the device that better meets specific requirements.