High actuation response of PVDF/PVP/PSSA based ionic polymer metal composites actuator

For the biomedical application of IPMC actuator, IPMC should generate fast and large tip displacement at low direct current (DC) and alternating current (AC) voltages of 1–2 V. In this paper, the tip displacement of polyvinylidene fluoride (PVDF)/polyvinyl pyrrolidone (PVP)/polystyrene sulfonic acid (PSSA) based ionic polymer metal composites (IPMCs) actuators were tested at DC and AC voltages of 1–2 V, and the results were compared with that of the Nafion based IPMC actuator. Research on the PVDF/PVP/PSSA ionic membrane identified two novel compositions of PVDF/PVP/PSSA of blend ratios of 25/15/60 and 30/15/55 for the IPMC actuator which gave higher ion exchange capacity (IEC) and higher water uptake (WUP) than that of the Nafion membrane and proton conductivity nearly equal to that of the Nafion membrane. In an ionic membrane, PVDF is the hydrophobic polymer, PVP the basic, water-soluble polymer, and PSSA the strong, water-soluble polyelectrolyte, which provides the free charge carrier. A high-performance ionic polymer actuator should have large IEC, large WUP and large proton conductivity. At DC and AC voltages of 1–2 V, the PVDF/PVP/PSSA based actuator showed larger actuation with quick response time than those of the Nafion based IPMC actuator. The capacitance and imaginary part of impedance of all IPMCs were calculated at AC voltages of 1–2 V and the actuation performances of IPMCs were also tested and compared.