6533b822fe1ef96bd127cfc6

RESEARCH PRODUCT

Porosity variation and swelling of cation exchangers

subject

description

Polystyrenesulfonic cation exchangers have been obtained from styrene‐divinylbenzene copolymers modified with organic solvents. The cation exchangers were characterized by varying porosity analogous to that of the parent copolymers. The porosity varied from zero to 0.45 and the specific surface area from zero to 350 m2/g; these changes were induced by drying the cation exchangers from poorly solvating solvents. The sorption degrees towards a model dye (methylene blue) from an aqueous solution reached a value up to unity and the pseudoequilibration time decreased with an increase in the sorption temperature. The sorption degrees of the dye from an acetone solution were lower and proportional to swelling of the gel in acetone. The presented results indicate that, similarly as in copolymers from which the cation exchangers were obtained, the structural changes occur on drying and they result from the surface tension of solvents, but the swollen cation exchangers have the gel structure.