Surface impregnated sulfonate ion exchangers: Preparation, properties and application

This paper reviews the results obtained by studying Surface Impregnated Sulfonate Ion Exchangers (SISIE) obtained by modification of macroporous or gel polysterene-divinylbenzene polymers with toluene solutions of dinonylnaphthalene sulfonic acids. Capacities of SISIE of the first type are directly proportional to the concentration of the modifying solution and to the specific surface area of the matrix. Capacities of gel SISIE are much less than those of macroporous samples and depend on the crosslinking of the matrix. Stabilization of SISIE capacity and improvement of their kinetic properties can be achieved using "wet drying " technique. Successive impregnation of the same SISIE sample may be used to increase the capacity of the resin. The ion-exchange properties of SISIE are mainly determined by their micellar structure which also defines the areas of possible applications of these ion-exchange materials such as, e.g. ion chromatography and some others. Several models have been successfully applied to describe the features of ion exchange processes on SISIE. Application of SISIE as convenient model systems to study aminecarboxylate interaction of amino acid molecules is illustrated by suspension effects measured in SISIE-zwitterlyte and SISIE-HCl suspensions and by the results obtained by the laser-acoustic study of these systems.