A theoretical prediction of the ions distribution in an amphoteric polymer gel

In order to obtain the optimum design for the realization of a high performance gel actuator, the ion distribution profiles in the gel are obtained theoretically by solving the Poisson–Bolzmann equation. Regardless of the types of ions (mobile cation, immobile cation, mobile anion and immobile anion), ion concentration is found to change abruptly at the electrode–gel interface. Based on this result, we found that gel could be deformed only in this interface region. Then we concluded that: (i) the use of an amphoteric gel rather than a cationic or an anionic gel; (ii) applying high voltage to gel; and (iii) the import of the electrode–gel interface as many as possible are promising strategies for the design of practical use gel actuator.