Cation exchange process, certain cation exchange resins and materials useful therein and processes for their preparation

Cation exchange processes can be carried out by treating liquids containing ionic impurities with particles, optionally in emulsion in aqueous media, of cation exchange resin which comprise approximately spherical beads of crosslinked copolymer having diameters of 0.01 to 1.5 micrometers and bearing 0.7 to 1.5 cation exchange functional groups per monomer unit. The particles may be removed from the treated liquid by flocculation. The particles or emulsions thereof may be made by emulsion polymerization followed by functionalization, in some cases after, in some cases at the same time as, and in some cases without, coagulation of the emulsion polymer to form coagulum particles of the copolymer beads which may, if necessary, be subsequently redispersed in liquids. Emulsions of the strong acid resins and particles of the weak acid resins in the free base form, both as such and in emulsions are also claimed.