Enhanced electroresponsive and electrochemical properties of the biological gel artificial muscle prepared by sodium alginate and carboxylated chitosan

At present, the Biological Gel Artificial Muscle (BGAM), an emerging chemical actuator, has advantages of large actuation, low driving voltage, excellent biocompatibility and flexibility, so it is widely used in biomedical engineering and soft robots etc. In this paper, effects and enhancement mechanisms of sodium alginate cross-linking carboxylated chitosan on electroresponsive and electrochemical properties of the BGAM were researched under single-cycle or repetition work period. And an experimental platform was established for testing electric conductivity and output force characteristics of the BGAM with different cross-linking mass ratios of sodium alginate and carboxylated chitosan. The results demonstrated that when the cross-linking mass ratio was 5:5, the BGAM was best cross-linked with crystallinity 26.08 %, and its internal polymer structure was fully cooperated by sodium alginate and carboxylated chitosan. Besides, specific capacitance, elastic modulus and internal resistance of the BGAM all reached a maximum value at 99.58 m F/g and the minimum values of 0.207 MPa and 1.616Ω, respectively. Thus, the optimum values of output force density and working life were also obtained for the BGAM, which were 7.213 mN/g and 1020s separately. In summary, these research findings indicate that the developed BGAM hold great promise for further study on high-performance chemical actuators.