Investigation into the high electroactuation performance of a gelatinous biomimetic artificial muscle constructed using glycyrrhiza polysaccharide cross-linking modification

Abstract

The Gelatinous Biomimetic Artificial Muscle (GBAM) is a novel actuator composed of intelligent polymer material capable of undergoing stretching, bending, tightening, or expansion by altering its internal structure in response to an applied electric field. This study employed sodium alginate (SA) and glycyrrhiza polysaccharides (GP) as the cross-linking agent to construct an electric-actuating membrane of the GBAM. Its electroactuation performance was assessed through the utilization of evaluation indicators including peak output force density (Dp), response speed (Vr), working life (TL), and duty cycle (Cd). By altering the electric-actuating membrane, the electroactuation performance of GBAM was enhanced. The findings indicated that following the GP cross-linking modification, the Dp value reached 22.69 mN/g, and the Vr value reached 0.093 mN/g·s. The TL value of 1262 s, the tremor frequency at only 53.4%, and the tremor amplitude at 8.3% of the control group were observed when the GP-SA cross-linking ratio was 4:5, leading to a much pronounced enhancement in the electroactuation performance of GBAM. When the GP-SA cross-linking ratio was 5:5, the elastic modulus exhibited a minimum value of 11.48 MPa, the Cd value demonstrated a minimum value of 13.5%, the specific capacitance attained a maximum value of 126.68 mF/g, the resistance value was measured at 2.22 Ω, the galvanostatic charge/discharge time was recorded as 5.3 s, and the energy value was quantified as 2.3 J. Furthermore, the GBAM displayed the most comprehensive internal structure, optimal cross-linking density, and superior performance in terms of output force, tensile strength, electrochemical behavior, and deflection displacement.