Description of Polymer Gel Properties in Framework of Generalized Mooney-Rivlin Model

A polymer gel is considered as a mixture consisting of a highly elastic elastic material and a liquid (solvent) dissolved in it. Based on the generalized Mooney-Rivlin model, an expression for free energy is proposed that describes the deformation behavior and thermodynamic properties of polymer gels. In this model, it is assumed that the Mooney-Rivlin "constants" depend on the concentration of the liquid dissolved in the polymer. From this expression, the constitutive relations for the stress tensor, the chemical potential of the solvent, and the osmotic stress tensor are obtained. Based on these relations, an experimental study of the deformation properties of cross-linked elastomers of various chemical natures swollen in a solvent is performed. In particular, the dependence of the elastic properties of elastomers on the concentration of the solvent is studied and the parameters describing this dependence are determined.