Effect of the degree of cross-linking on the selectivity of cationites andanionites on styrene-divinylbenzene matrices

The influence of the degree of cross-linking of cationites and anionites th at were prepared on the basis of polystyrene matrices on the relationships between the apparent constant (K) over tilde for simple ion-exchange equili bria and the equivalent fraction (x) over bar of entering ions is examined. It is shown that the complicated behavior of this dependence for highly cr oss-linked styrene-divinylbenzene sulfocationites is largely determined by the presence of functional groups in the benzene rings belonging to the cro ss-linking bridges. For anionites, the (K) over tilde = f((x) over bar) dep endence is simple because the cross-linking sites contain no functional gro ups, and consequently an increase in the degree of cross-linking does not l ead to higher local concentrations of functional groups.