Abstract: A process for producing a multivalent cation containing copolymer, containing: contacting a multivalent cation containing ethylenically unsaturated acid and at least one comonomer to produce a monomer mixture comprising the multivalent cation containing ethylenically unsaturated acid present in an amount in the range of from about 5% to about 65% by weight; and contacting the monomer mixture with a redox initiator comprising a reducing compound and an oxidising compound and contacting the monomer mixture with a thermal initiator to cause the multivalent cation containing ethylenically unsaturated acid and the at least one comonomer to react to produce the multivalent cation containing copolymer, wherein the thermal initiator is used in the range 100 to 5000 ppm.

Abstract: There is disclosed a multivalent cation containing copolymer derived from one or more ethylenically unsaturated acids. The copolymer has the following characteristics: (a) an intrinsic viscosity of at least about 3 dl/g when measured in 1 M Na Cl solution at 25° C.; (b) the copolymer is derived from a monomer mixture comprising an ethylenically unsaturated acid and at least one comonomer, the ethylenically unsaturated acid present in an amount in the range of from about % to about 65% by weight; and (c) a residual comonomer content is less than 1000 ppm when the comonomer is an acrylamide. The copolymer, inter alia, is useful as a flocculant for treating an aqueous slurry comprising particulate material, preferably tailings from a mining operation.

Abstract: A process for producing a multivalent cation containing copolymer, containing: contacting a multivalent cation containing ethylenically unsaturated acid and at least one comonomer to produce a monomer mixture comprising the multivalent cation containing ethylenically unsaturated acid present in an amount in the range of from about 5% to about 65% by weight; and contacting the monomer mixture with a redox initiator comprising a reducing compound and an oxidising compound and contacting the monomer mixture with a thermal initiator to cause the multivalent cation containing ethylenically unsaturated acid and the at least one comonomer to react to produce the multivalent cation containing copolymer, wherein the thermal initiator is used in the range 100 to 5000 ppm.

Abstract: There is disclosed a multivalent cation containing copolymer derived from one or more ethylenically unsaturated acids. The copolymer has the following characteristics: (a) an intrinsic viscosity of at least about 3 dl/g when measured in 1 M Na Cl solution at 25° C.; (b) the copolymer is derived from a monomer mixture comprising an ethylenically unsaturated acid and at least one comonomer, the ethylenically unsaturated acid present in an amount in the range of from about % to about 65% by weight; and (c) a residual comonomer content is less than 1000 ppm when the comonomer is an acrylamide. The copolymer, inter alia, is useful as a flocculant for treating an aqueous slurry comprising particulate material, preferably tailings from a mining operation.