On the other hand, ionomeric polymer-metal composites (IPMC) are strained as result of the cation mobility caused by electrical
stimulation. They require relatively low voltages (<10V).
Reversible counter-ion insertion and expulsion that occurs during redox cycling is
primarily responsible for the actuation of conductive polymers. Significant volume changes occur through oxidation and reduction reactions at corresponding electrodes through exchanges of ions with an electrolyte.
Conducting polymer actuators require voltages in the range of 1-5 V and variations to the voltage can control actuation speeds. Applications for conducting polymers include miniature boxes that have the ability to open
and close, micro-robots and surgical tools
One of the latest additions to electroactive species is carbon nanotubes. The actuation mechanism is through an electrolyte medium and the change in bond length occurs via
the injection of charges that affect the ionic charge balance between the nanotube and the electrolyte. The deformation is proportional to the amount of charge injected into the nanotube.