Cation-exchangers from cross-linked polyhydroxy materials

Claim 1

AS A NOVEL COMPOUND, A COPOLYMERIZATE OF: (A) A MEMBER SELECTED FROM THE GROUP CONSISTING OF DEXTRAN, SUCROSE, STARCH, SORBITOL, DEXTRIN; POLYVINYL ALCOHOL AND HYDROXYETHYL CELLULOSE, (B) A BI-FUNCTIONAL ORGANIC SUBSTANCE SELECTED FROM THE GROUP CONSISTING OF EPICHLOROHYDRIN, BIS-EPOXYPROPYLETHER AND ETHYLENE GLYCOL-BIS-EPOXY PROPYL ETHER WHICH IS CAPABLE OF LINKING TOGETHER THE AFORESAID MEMBERS BY THE FORMATION OF ETHER LINKAGES; (C) SAID COPOLYMERIZATE ORIGINALLY CONTAINING FROM 10 TO 35 PERCENT OF HYDROXYL GROUPS, BASED ON THE WEIGHT OF THE DRY SUBSTANCE, AND HAVING FROM 6 TO 50 PERCENT OF THEIR HYDROXYL GROUPS ORIGINALLY PRESENT IN THE FORMATION SUBSTITUTED BY A MEMBER SELECTED FROM THE GROUP CONSISTING OF RADICALS OF THE TYPE R1Y, WHEREIN (D) R1 IS AN ALKYLENE CONTAINING FROM ONE TO TWO, INCLUSIVE, CARBON ATOMS, AND (E) Y IS SELECTED FROM THE GROUP CONSISTING OF CARBOXYL AND SULFO; AND SAID NOVEL COMPOUND, (F) BEING INSOLUBLE IN WATER BUT CAPABLE OF SWELLING THEREIN; (G) HAVING A WATER REGAIN WITHIN THE RANGE OF 1-50 GRAMS PER GRAM OF THE DRY COMPOUND, AND (H) HAVING AN ION-EXCHANGE CAPACITY WITHIN THE RANGE OF FROM 2 TO 6 MILLIEQUIVALENTS PER GRAM OF THE DRY COMPOUND.