US 5,206,326 A · Grafted copolymers highly absorbent to aqueous electrolyte solutions

Abstract

The present invention provides graft copolymers that are highly absorbent to aqueous electrolyte solutions. The graft copolymer is formed by the graft polymerizing an effective amount of each of the following components together to provide a highly absorbent copolymer: (a) graft polymerizing onto a first polymer selected from the group consisting of polysaccharide, polypropylene, polyethylene and other polyolefins, and at least one comonomer selected from the group consisting of acrylamide, methacrylamide, acrylonitrile, acrylic acid, methacrylic acid, alkali salts of acrylic acid, alkali salts of methacrylic acid, 2-methacryloyloxyethyldiethylamine, 2-acrylamido-2-methylpropane sulfonic acid, alkali salts of 2-acrylamido-2-methylpropane sulfonic acid, 2-methacryloyloxyethane sulfonic acid, alkali salts of 2-methacryloyloxyethane sulfonic acid, and any combination of two or more thereof; and (b) graft polymerizing therewith an ampholytic ion pair monomer comprising (i) an ammonium cation 2-methacryloyloxyethyldiethylammonium and (ii) a sulfonate anion selected from the group consisting of 2-acrylamido-2-methylpropane sulfonate, 2-methacryloyloxyethane sulfonate, vinyl sulfonate, styrene sulfonate and any combination of thereof.

Claims26

Dependent claims

A graft copolymer formed by:

(A) graft polymerizing onto a first polymer selected from the group consisting of polysaccharide, polypropylene, and polyethylene;
at least one comonomer selected from the group consisting of acrylamide, methacrylamide, acrylonitrile, acrylic acid, methacrylic acid, alkali salts of acrylic acid, alkali salts of methacrylic acid, 2-methacryloyloxyethyldiethylamine, 2-acrylamido-2-methylpropane sulfonic acid, alkali salts of 2-acrylamido-2-methylpropane sulfonic acid, 2-methacryloylozyethane sulfonic acid, alkali salts of 2-methacryloyloxyethane sulfonic acid, N-vinyl-2-pyrrolidone and combinations of two or more thereof;
(B) graft copolymerizing therewith an ampholytic ion pair monomer having an ammonium cation and a sulfonate anion wherein
(i) the ammonium cation is 2-methacryloyloxyethyldiethylammonium;
and
(ii) the sulfonate anion is selected from the group consisting of 2-acrylamido-2-methylpropane sulfonate, 2-methacryloyloxyethane sulfonate, vinyl sulfonate, styrene sulfonate and any combination of two or more thereof;
wherein the comonomers and ion pair monomers are provided in amounts which are effective to produce a highly absorbent graft copolymer;
and
(C) partially saponifying neutralization of said graft copolymer formed in step (B).

6 more elements

A method of absorbing an aqueous electrolyte solution comprising contacting a graft copolymer form by:

(A) graft polymerizing onto a first polymer selected from the group consisting of polysaccharide, polypropylene, and polyethylene;
at least one comonomer selected from the group consisting of acrylamide, methacrylamide, acrylonitrile acrylic acid, methacrylic acid, alkali salts of acrylic acid, alkali salts of methacrylic acid, 2-methacryloyloxyethyldiethylamine, 2-acrylamido-2-methylpropane sulfonic acid, alkali salts of 2-acrylamido-2-methylpropane sulfonic acid, 2-methacryloyloxyethane sulfonic acid, alkali salts of 2-methacryloyloxyethane sulfonic acid, N-vinyl-2-pyrrolidone and combinations of two or more thereof;
(B) graft copolymerizing therewith an ampholytic ion pair monomer having an ammonium cation and a sulfonate anion wherein
(i) the ammonium cation is 2-methacryloyloxyethyldiethylammonium;
and
(ii) the sulfonate anion is selected from the group consisting of 2-acrylamido-2-methylpropane sulfonate, 2-methacryloyloxyethane sulfonate, vinyl sulfonate, styrene sulfonate and any combination of two or more thereof;
wherein the comonomers and ion pair monomers are provided in amounts which are effective to produce a high absorbent graft copolymer;
and
(C) partially saponifying neutralization of said graft copolymer formed in step (B);
with an electrolyte solution.

7 more elements

Dependencies are inferred from the claim text.

Grafted copolymers highly absorbent to aqueous electrolyte solutions

Life of this patent

Grafted copolymers highly absorbent to aqueous electrolyte solutions

Life of this patent

Abstract

Claims26