Cation-exchange resins polyfunctional

The acrylic weak base resins are synthesized from copolymers similar to those used for the manufacture of weak acid cation-exchange resins. For example, under appropriate temperature and pressure conditions, a weak acid resin reacts with a polyfunctional amine, such as dimethylaminopropylamine [109-55-7] (7) to give a weak base resin with a tertiary amine functionality. 

A polyfunctional cation-exchange resin prepared by heating a mixture of furfural and /)-phenolsulphonic acid with a prepolymer from furylacrylic add at 60 °C for 5-6 h is stable up to 100 °C, swells 135 % in water (in H form), and possesses static exchange capadty of 4.9-5.0, 2.3, 2.7, and 3.5 meq/g for O.IN NaOH, O.IN CaQj, —COOH groups, and O.IN salsolidine, respectively. 

The condensation of furfural with resordnol in presence of hydrochloric add at 34-35 °C followed by sulfonation of the condensate affords a polyfunctional cation-exchange resin containing —SO3H, —COOH, and —OH (phenolic) groups. The carboxylic activity of this resin has been attributed to the oxidation of furfurylic... 

---