Font Size: 

Double network (DN) gels are soft-elastic materials consisting of a three-dimensional cross-linked polymer network and liquid filling the space among such network. To take advantage of the swelling-deformation behavior of DN gel and explore its possibility for applications in engineering as a structural member, the effect of concentration of ions in the solution on the deformation behavior of DN gel should be clarified, especially when the DN gel is loaded inside the solution. In this study, we at first proposed a nonaffine model for the DN gel to account for the change of the entangling structure of polymer chains during the swelling-deformation process, in which the change of the number of polymer chains per unit volume is depending on the first invariant of right Cauchy-Green deformation tensor. And then, the swelling ratio and the simple tensional mechanical response of DN gel is calculated when the DN gel is loaded inside the solution with different concentration of ions. The results show that the nonaffine model can reproduce the experimental results of the swelling ratio very well. Moreover, the high concentration of ions leads to the high deformation resistance.

Gel, Concentration of ion, Nonaffine model, Swelling ratio, Simple tension