The effect of the nature and concentration of solutions of various metals, the nature of
co-ions, the amount of cross-links, and the activity of water on the swelling of gels based on
polystyrene and divinylbenzene in solutions of these compounds has been studied. Using the osmotic
coefficients of these electrolytes on the basis of the experimental results, the change in the Gibbs
energy of the swelling process was calculated.