Patent GB-894391-A (GB)
Title: Polymeric cation exchangers with a sponge structure
IPC: B01J39/20
Filed: 1958-04-21
Abstract: A cation-exchange resin having a cross-linked matrix with acid groups bonded thereto is derived from a matrix obtained by copolymerizing (1) a monoethylenically unsaturated monomer and (2) a polyethylenically unsaturated cross-linking agent, in solution in 10 to 300% of an inert organic liquid which will dissolve the monomers but not linear polymers of the monomer (1), whereby there is obtained a solid, cross-linked, non-proliferous copolymer permeated by small veins having occluded therein organic liquid, which is then removed from the polymer.  The polymerization preferably is carried out with the dissolved monomers suspended in an aqueous medium containing a peroxy or azo compound as catalyst and materials such as methyl cellulose or gelatine as dispersing agents, whereby the copolymers are obtained as beads.  The matrix may be derived from acrylic, methacrylic, maleic or fumaric acid or an ester (including semi-ester) thereof, styrene, methyl or ethyl styrene, vinyl anisole or naphthalene, in conjunction with divinyl benzene, trivinyl benzene, ethylene glycol dimethacrylate or diacrylate, diallyl maleate, divinyl ketone, divinyl ether or ethylene glycol dimaleate. The acid groups such as carboxylic, sulphonic, phosphonic or phosphinic groups, may be introduced either by copolymerization or by after-treatments of cross-linked polymers, e.g. by saponification of ester groups, by the use of PCl3 followed by saponification with/without oxidation, by sulphonation, or by haloalkylation followed by reaction with trialkyl phosphites.  Inert organic liquids specified are benzine, white spirit, dodecane, cyclohexanol, methanol, amyl alcohol, dodecanol, decanol, oleyl alcohol, nitromethane, nitropropane, nitrohexane, diethyl ether, dibutyl ether and diamyl ether. Specifications 577,707, 659,775, 670,145, 789,952, 794,793 and 894,392 are referred to.ALSO:A cation-exchange resin having a cross-linked matrix with acid groups bonded thereto is derived from a matrix obtained by copolymerizing (1) a monoethylenically unsaturated monomer and (2) a polyethylenically unsaturated cross-linking agent, in solution in 10 to  300% of an inert organic liquid which will dissolve the monomers but not linear polymers of the monomer (1), whereby there is obtained a solid, cross-linked, non-proliferous copolymer permeated by small veins having occluded therein organic liquid, which is then removed from the polymer.  The polymerization preferably is carried out with the dissolved monomers suspended in an aqueous medium containing a peroxy or azo compound as catalyst and materials such as methyl cellulose or gelatine as dispersing agents, whereby the copolymers are obtained as beads. The matrix may be derived from acrylic, methacrylic, maleic or fumaric acid or an ester (including semiester) thereof, styrene, methyl or ethyl styrene, vinyl anisole or naphthalene, in conjunction with divinyl benzene, trivinyl benzene, ethylene glycol dimethacrylate or diacrylate, diallyl maleate, divinyl ketone, divinyl ether or ethylene glycol dimaleate.  The acid groups such as carboxylic, sulphonic, phosphonic or phosphinic groups, may be introduced either by copolymerization or by after-treatments of cross-linked polymers, e.g. by saponification of ester groups, by the use of PCl3 followed by saponification with/without oxidation, by sulphonation, or by haloalkylation followed by reaction with trialkyl phosphites.  Inert organic specified are benzine, white spirit, dodecane, cyclohexanol, methanol, amyl alcohol, dodecanol, decanol, oleyl alcohol, nitromethane, nitropropane, nitrohexane, diethyl ether, dibutyl ether and diamyl ether.  Specifications 577,707, 659,775, 670,145, 789,952, 794,793 and 894,392 are referred to.