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US 4,432,881 AGranted
Water-dispersible hydrophobic thickening agent
AssigneeThe Dow Chemical Company
InventorSyamalarao Evani
Life of this patent
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Abstract
An aqueous liquid medium having increased low shear viscosity as provided by dispersing into the aqueous medium (1) a water-soluble polymer having pendant hydrophobic groups, e.g., an acrylamide dodecyl acrylate copolymer, and (2) a water-dispersible surfactant, e.g., sodium oleate, or dodecyl polyethyleneoxy glycol monoether. The thickened aqueous medium is suitably emloyed in applications requiring viscous liquids which retain their viscosity when subjected to shear, heat or high electrolyte (salt) concentrations. Such applications include uses in enhanced oil recovery processes, as fluid mobility control agents, fracturing fluids and drilling muds, as well as hydraulic fluids and lubricants in many applications.
Claims36
A water soluble composition for thickening aqueous liquids comprising
- (A) a water-soluble thickening agent which agent comprises
- (1) a water-soluble polymer having pendant hydrophobic groups, said polymer being a copolymer of a water-soluble ethylenically unsaturated monomer and water-insoluble ethylenically unsaturated monomer having a hydrophobic group having at least 8 carbon atoms, wherein
- (a) the water-soluble monomer is an ethylenically unsaturated amide or an N-substituted derivative thereof, an ethylenically unsaturated carboxylic acid, an ethylenically unsaturated quaternary ammonium compound, a sulfoalkyl ester of an unsaturated carboxylic acid, an aminoalkyl ester of an unsaturated carboxylic acid, a diallylamine, a diallylammonium compound or a vinylaryl sulfonate,
- and
- (b) the water-insoluble monomer is a higher alkyl ester of an .alpha.,.beta.-ethylenically unsaturated carboxylic acid, an alkylaryl ester of an ethylenically unsaturated carboxylic acid, an N-alkyl ethylenically unsaturated amide, vinyl alkyl ether or an ar-alkyl styrene;
- and
- (2) a water-dispersible nonionic surfactant having hydrophobic groups that are capable of associating with the hydrophobic groups of the copolymer such that at ambient conditions, water containing 0.5 weight percent of the thickening agent has a viscosity at least twice the viscosity of water, said thickening agent having a weight ratio of the copolymer to the surfactant in the range from about 20:1 to about 0.5:1, and
- (B) a water-soluble inorganic salt in an amount such that at a temperature in the range up to about 80.degree. C., an aqueous medium containing a viscosity increasing amount of the thickening agent exhibits a further increase in viscosity when the water-soluble salt is added to the medium.
5 more elements
A water-soluble composition for thickening aqueous liquids which composition comprises
- (A) a water-soluble thickening agent comprising
- (1) a water-soluble polymer having pendant hydrophobic groups, said polymer being a copolymer of a water-soluble ethylenically unsaturated monomer and water-insoluble ethylenically unsaturated monomer having a hydrophobic group, wherein
- (a) the water-soluble monomer is acrylamide, methacrylamide and fumaramide;
- 2-acrylamide-2-methylpropane sulfonic acid, N-(dimethylaminomethyl)acrylamide, N-(trimethylammoniummethyl)acrylamide chloride, N-(trimethylammoniumpropyl)methacrylamide chloride, acrylic acid, methacrylic acid, itaconic acid and fumaric acid, vinylbenzyl trimethyl ammonium chloride, 2-sulfoethyl methacrylate, 2-aminoethyl methacrylate, vinyl pyridine, vinyl morpholine, diallyl dimethyl ammonium chloride, vinyl pyrrolidone or a salt of vinylbenzyl sulfonate
- and
- (b) the water-insoluble monomer is 2-ethylhexyl methacrylate, dodecyl acrylate, dodecyl methacrylate, tridecyl acrylate, tridecyl methacrylate, tetradecyl acrylate, tetradecyl methacrylate, octadecyl acrylate, octadecyl methacrylate, ethyl half ester of maleic anhydride, diethyl maleate, and other alkyl esters derived from the reactions of alkanols having from 8 to 20 carbon atoms with ethylenically unsaturated carboxylic acids selected from the group consisting of acrylic acid, methacrylic acid, maleic anhydride, fumaric acid, itaconic acid and aconitic acid, nonyl-.alpha.-phenyl acrylate, nonyl-.alpha.-phenyl methacrylate, dodecyl-.alpha.-phenyl acrylate, dodecyl-.alpha.-phenyl methacrylate, N-octadecyl acrylamide, N-octadecyl methacrylamide, N,N-dioctyl acrylamide;
- octene-1, decene-1, dodecene-1, hexadecene-1, vinyl laurate, vinyl stearate, dodecyl vinyl ether, hexadecyl vinyl ether, N-vinyl lauramide, N-vinyl stearamide or t-butyl styrene;
- (2) a water-dispersible nonionic surfactant having hydrophobic groups that are capable of associating with the hydrophobic groups of the copolymer such that at ambient conditions, water containing 0.5 weight percent of the thickening agent has a viscosity at least twice the viscosity of water, said thickening agent having a weight ratio of the copolymer to the surfactant in the range from about 20:1 to about 0.5:1;
- and
- (B) a water-soluble inorganic salt of a metal in an amount such that at a temperature in the range up to about 80.degree. C., an aqueous medium containing a viscosity increasing amount of the thickening agent exhibits a further increase in viscosity when the water-soluble salt is added to the medium, said amount of salt being in the range from about 0.01 to about 20 weight percent based on the medium.
7 more elements
The composition of 15 wherein the polymer is a copolymer of from about 60 to about 99.9 mole percent of acrylamide, from 0 to about 30 mole percent of acrylic acid and from about 0.1 to about 10 weight percent of dodecyl methacrylate and the surfactant is a dodecyl polyethyleneoxy glycol monoether wherein the monoether has about 1 to 10 ethyleneoxy groups per molecule.
A thickened aqueous composition which composition comprises
- (A) water having dispersed therein
- (1) a viscosity increasing amount of a water-soluble copolymer of from about 40 to about 99.9 mole percent of acrylamide, from 0 to about 50 mole percent of acrylic acid and from about 0.1 to about 10 mole percent of an alkyl methacrylate or acrylate wherein alkyl has from 8 to 12 carbon atoms;
- (2) an alkyl polyethyleneoxy glycol monoether wherein alkyl has from 8 to 20 carbon atoms and there are from 1 to 12 ethyleneoxy groups per molecule of the monoether;
- and
- (3) from about 0.01 to about 20 weight percent of a salt of an alkali metal or an alkaline earth metal;
- in said composition the weight ratio of copolymer to monoether being in the range from about 20:1 to about 0.5:1.
3 more elements
A thickened aqueous composition comprising an aqueous medium having dispersed therein
- (1) from about 0.1 to about 1 weight percent of a water-soluble copolymer of 40 to about 99.9 mole percent of acrylamide, from 0 to about 50 mole percent of acrylic acid and from about 0.1 to about 10 mole percent of an alkyl methacrylate or acrylate wherein alkyl has from 8 to 12 carbon atoms, said copolymer having a weight average molecular weight in the range from about 800,000 to about 3 million;
- (2) from about 0.0015 to about 0.5 weight percent of an alkyl polyethyleneoxy glycol monoether wherein alkyl has from 8 to 20 carbons and there are from 1 to 12 ethyleneoxy groups per molecule of monoether;
- and
- (3) from about 0.01 to about 20 weight percent of a salt of an alkali metal or an alkaline earth metal, said alkyl groups of the monoether being capable of associating with the alkyl groups of the copolymer in the thickened aqueous composition, and said copolymer, monoether and salt being present in amounts sufficient to increase the viscosity of the aqueous medium.
1 more element
A thickened aqueous composition comprising
- (A) an aqueous medium having dissolved therein;
- (B) a viscosity increasing amount in the range from about 0.025 to about 5 weight percent of a thickening agent comprising
- (1) a copolymer of from about 98 to about 99.995 mole percent of one or more water-soluble ethylenically unsaturated monomers and from about 0.005 to about 2 mole percent of one or more water-insoluble ethylenically unsaturated monomers having hydrophobic groups having at least 8 carbon atoms wherein the water-insoluble monomer is a higher alkyl ester of an .alpha.,.beta.-ethylenically unsaturated carboxylic acid, an alkylaryl ester of an ethylenically unsaturated carboxylic acid, an N-alkyl ethylenically unsaturated amide or an ar-alkyl styrene, and
- (2) a water-dispersible, nonionic surfactant having hydrophobic groups that are capable of associating with the hydrophobic groups of the copolymer wherein the weight ratio of copolymer to surfactant is in the range from about 20:1 to about 0.5:1;
- and
- (C) an amount of a water-soluble inorganic salt in the range from about 0.01 to about 20 weight percent based on the medium which is sufficient to increase the viscosity of the aqueous medium containing the thickening agent.
3 more elements
Dependencies are inferred from the claim text.