Polypyrrole films with anisotropy

The novel features of electrochemical actuators fabricated using cylindrical polypyrrole (PPy) fibers prepared by electrochemical polymerization techniques are described. A Ni wire with a Teflon-made slender pipe was used as a working electrode. If the inner wall side (contacting surface with electrolyte when PPy was polymerized) was insulated and the redox was carried out, the PPy fiber bends toward the outer side, but the bending was not completely observed when the outer wall side was insulated Although such an anomalous bending in PPy-fiber actuator canʹt be explained satisfactorily at this stage, we speculate that the bending phenomena are due to the difficulty of dopant transfer between the inner and outer wall sides.