Modifizierte ionenaustauscherharze — synthese und eigenschaften, 1. Sulfomethylierte styrol-divinylbenzol-harze

Sulfomethylated resins are prepared by polymer analogous reactions, starting from macroporous poly(styrene-co-divinylbenzene) matrices. Different reaction paths are discussed and used in the synthesis. Sulfomethylation can be achieved by reaction of a chloromethylated resin with dimethyl sulfide and sodium sulfonate or alternatively by oxidation of polymer-bound thiol groups. Both methods give high conversions as shown by IR spectra and titration of the sulfonic acid groups. Poly[1-(4-hydroxysulfomethylphenyl)ethylene] (3) is obtained by reaction of poly[1-(4-hydroxyphenyl)ethylene] ( 2 ) resin with formaldehyde/sodium sulfonate. The thermal stability, catalytic activity, and ion exchange equilibria of the sulfomethylated resin are investigated.