Carboxylic acid thickener having improved performance under alkaline conditions
AssigneeThe B. F. Goodrich Company
InventorsTonson Abraham, William F. Masler, III
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Abstract
An alkaline mixture of a cross-linked carboxylic acid copolymer having improved performance under alkaline conditions, such as a pH of 10 or higher which is a copolymer of a monomeric mixture of 6.5 to 97 phr of a carboxylic acid and 0.5 to 30 phr of an N-substituted acrylamide, such as isopropyl acrylamide, diacetone acrylamide, t-octylacrylamide, or t-butylacrylamide, which copolymer is cross-linked with 0.05 to 5 percent by weight based upon the weight of the copolymer of a polyunsaturated cross-linking agent, and an alkali or alkaline earth hydroxide, carbonate, phosphate or amine.
Claims20
An alkaline mixture comprising a cross-linked carboxylic acid copolymer having improved performance under alkaline conditions comprising a copolymer of a monomeric mixture of 65 to 97 phr of a carboxylic acid monomer and 0.5 to 30 phr of an N-substituted acrylamide monomer selected from the group consisting of t-butyl acrylamide, t-octyl acrylamide, diacetone acrylamide, and isopropyl acrylamide, said copolymer being cross-linked with 0.05 to 5 percent by weight based upon the weight of the copolymer of a polyunsaturated cross-linking agent and an alkali or alkaline earth hydroxide, carbonate, phosphate or amine wherein the mixture has a pH of greater than about 10.
A process of thickening aqueous alkaline mixtures comprising adding to an aqueous alkaline mixture a copolymer of a monomeric mixture of 65 to 97 parts per hundred monomer of a carboxylic acid monomer and 0.5 to 30 parts per hundred monomer of an N-substituted acrylamide selected from the group consisting of t-butyl acrylamide, t-octyl acrylamide, diacetone acrylamile, and isopropyl acrylamide, said copolymer being cross-linked with 0.05 to 5 percent by weight, based upon the weight of the copolymer, of a polyunsaturated cross-linking agent wherein the mixture has a pH of greater than about 10.
Dependencies are inferred from the claim text.