Synthesis and characterization of EDOT-based conducting polymer actuators

Freestanding films of poly(3,4-ethylenedioxythiopene), PEDOT, were synthesized electrochemically from a solution containing EDOT monomer, tetrabutylammonium hexafluorophosphate, and water in propylene carbonate. The films were tested mechanically under constant stresses ranging from 0.6 to 2.1 MPa and subjected to various electrochemical waveforms while immersed in a bath containing propylene carbonate and an electrolyte. The characterization resulted in observations of ultimate linear strains of 2%, strain rates of 0.003 Hz, and strain to charge densities of 4 x 10^-10 m³/C, comparable to the conventional conducting polymer polypyrrole. In addition to the quantitative analysis, evidence of both anionic and cationic intercalation into the polymer is presented with a discussion of prospective mechanisms and consequences.