Abstract: The invention relates to a water-soluble branched sulfonated amphoteric polymer, for a water-based drilling fluid, wherein the polymer is obtained by precipitation polymerization, in a mixture of polar solvents, of at least one N,N?-dialkylacrylamide monomer and one sulfonic acid-containing monomer, in the presence of tetraallylammonium halide as branching agent. The invention also relates to a water-based drilling fluid for subterranean boreholes, including: an aqueous fluid, said aqueous fluid being selected from sea water, brine, or salt-containing aqueous solution, between 0.1 and 5.0 weight percent of the water-soluble branched sulfonated amphoteric polymer described above.

Abstract: The present invention relates to a hydrated crystalline form of 2 -acrylamido-2-methylpropane sulfonic acid having a 2-theta powder X-ray diffraction diagram comprising peaks at 10.58°, 11.2°, 12.65°, 13.66°, 16.28°, 18.45°, 20°, 20.4°, 22.5°, 25.5°, 25.88°, 26.47°, 28.52°, 30.28°, 30.8°, 34.09°, 38.19°, 40.69°, 41.82°, 43.74°, 46.04° degrees (+/? 0.1°. The present invention also relates to a production method for this form of 2-acrylamido-2-methylpropane sulfonic acid and a preparation method for an aqueous solution A of a salt of this form of 2-acrylamido-2-methylpropane sulfonic acid, and the (co)polymer of this form of -acrylamido-2-methylpropane sulfonic acid.

Abstract: The present invention relates to a polymer preparation method for preparing water-soluble cationic polymers P1 wherein the halides content is reduced, as well as to the use of these polymers as additives in compositions that are based on inorganic mineral binders or in the treatment of aqueous open, semi-closed, or closed circuits.

Abstract: The present invention is concerned with the treatment of produced water, obtained from a chemically enhanced oil recovery process using viscosity-increasing polymeric compounds. Said treatment comprises particularly the steps of obtaining a produced water, from an oil-water mixture recovered from an oil-bearing formation, wherein the produced water comprises the viscosity-increasing polymeric compounds; and, of directing the produced water to a specific filtration device, and subjecting the produced water to filtration, for obtaining a retentate stream and a permeate stream. Said process allows particularly obtaining a permeate comprising the viscosity-increasing polymeric compounds, said permeate being substantially free of suspended solids, free oil and emulsified oil.

Abstract: The present invention relates to a hydrated crystalline form of 2-acrylamido-2-methylpropane sulfonic acid having a 2-theta powder X-ray diffraction diagram comprising peaks at 10.58°, 11.2°, 12.65°, 13.66°, 16.28°, 18.45°, 20°, 20.4°, 22.5°, 25.5°, 25.88°, 26.47°, 28.52°, 30.28°, 30.8°, 34.09°, 38.19°, 40.69°, 41.82°, 43.74°, 46.04° degrees (+/?0.1°). The present invention also relates to a production method for this form of 2-acrylamido-2-methylpropane sulfonic acid and a preparation method for an aqueous solution A of a salt of this form of 2-acrylamido-2-methylpropane sulfonic acid, and the (co)polymer of this form of -acrylamido-2-methylpropane sulfonic acid.

Abstract: The invention relates to a water-soluble branched sulfonated amphoteric polymer, for a water-based drilling fluid, wherein the polymer is obtained by precipitation polymerization, in a mixture of polar solvents, of at least one N,N?-dialkylacrylamide monomer and one sulfonic acid-containing monomer, in the presence of tetraallylammonium halide as branching agent. The invention also relates to a water-based drilling fluid for subterranean boreholes, including: an aqueous fluid, said aqueous fluid being selected from sea water, brine, or salt-containing aqueous solution, between 0.1 and 5.0 weight percent of the water-soluble branched sulfonated amphoteric polymer described above.

Abstract: The present invention relates to a production process for 2-acrylamido-2-methylpropane sulfonic acid including at least the following successive steps: 1) mixing of acrylonitrile with at least one compound contributing SO3 at a temperature included between ?80 and 30° C.; 2) placing in contact and mixing isobutylene and the sulfonating mixture with a molar ratio of SO3 to isobutylene included between 0.2:1 and 2:1 and a molar ratio of acrylonitrile to isobutylene included between 3:1 and 60:1 at a temperature included between ?40 and 100° C.; 3) solid/liquid separation of the reaction mixture and isolation of the solid particles in the form of a composition 1; 4) mixing composition 1 at the end of step 3) with an aqueous solution A included at a temperature comprised between ?20 and 70° C. in order to obtain a suspension 1 of 2-acrylamido-2-methylpropane sulfonic acid crystals; 5) solid/liquid separation of the suspension 1 and isolation of the crystals in form of composition 2.

Abstract: The invention relates to a method for producing 2-acrylamido-2-methylpropane sulfonic acid. Said method consists in reacting together acrylonitrile, fuming sulfuric acid and isobutylene. It is characterized in that the isobutylene contains less than 1000 ppm of butadiene and less than 1000 ppm of butene.

Abstract: Provided is a composition for preparing injection fluid in oil and gas recovery comprising an inverse emulsion of a water-soluble polymer A comprising acrylamide monomer units, and solid particles of a water-soluble polymer, wherein water-soluble polymer B is obtained by a polymerization step of at least acrylamide and 1 and 15 mol % of acrylamido tertiary butyl sulfonic acid (ATBS), and/or salts thereof, and a subsequent post treatment step of the resulting polymer. Also provided is a method of treating a portion of subterranean formation comprising providing the composition, preparing an injection fluid with at least the composition, introducing the injection fluid into portion of the subterranean formation. The composition is particularly useful to prepare fracturing fluid in fracturing operations.

Abstract: The present invention concerns a method for determining the concentration of cationic polymers present in a sample, according to the following steps: —bringing the cationic polymer or polymers present in the sample into contact with, and enabling the interaction thereof with, a developer solution comprising lanthanide (III) ions and at least one bonding agent, and —exciting the sample at an excitation wavelength ?exc and detecting, by time resolved photoluminescence, a signal originating from the lanthanide (III) ions having interacted with the at least one bonding agent having previously interacted with the cationic polymer or polymers, at an emission wavelength ?em, and —determining the cationic polymer concentration of the sample by using the signal detected at the emission wavelength ?em, the sample originating from water originating from municipal or industrial water or sludge treatment processes.

Abstract: The present invention relates to a method for enhanced oil recovery by flushing an underground formation, comprising the injection into the underground formation of an aqueous composition comprising microgels having at least one crosslinked polymer, characterized in that the polymer is crosslinked with at least one crosslinking agent capable of being degraded under the temperature conditions of the underground formation, and a content of crosslinking agent between 1 and 90 ppm per mole with respect to the total number of moles of monomer constituting the polymer.

Abstract: The present invention relates to a method for the treatment of a suspension of solid particles in water using water-soluble (co)polymers made from the hydrated crystalline form of 2-acrylamido-2-methylpropane sulfonic acid or of at least one of the salts thereof This method is particularly useful for treating residues resulting from the mining industry.

Abstract: A process for enhanced oil recovery comprising the following steps: a) Preparation of an injection fluid comprising at least one water-soluble (co)polymer prepared at least from 2-acrylamido-2-methylpropane sulfonic acid (ATBS) or from at least one of its salts, with water or with brine, where the 2-acrylamido-2-methylpropane sulfonic acid is a hydrated crystalline form of 2-acrylamido-2-methylpropane sulfonic acid having a 2-theta powder X-ray diffraction diagram comprising peaks at 10.58°, 11.2°, 12.65°, 13.66°, 16.28°, 18.45°, 20°, 20.4°, 22.5°, 25.5°, 25.88°, 26.47°, 28.52°, 30.28°, 30.8°, 34.09°, 38.19°, 40.69°, 41.82°, 43.74°, 46.04° degrees. b) Injection of injection fluid into an underground formation, c) Flushing of the underground formation using the fluid injected, d) Recovery of an aqueous and hydrocarbon mixture.

Abstract: The present invention relates to a fracturation fluid comprising at least one propping agent and at least one water-soluble (co)polymer prepared from the hydrated crystalline form of 2-acrylamido-2-methylpropane sulfonic acid and/or at least one of its salts. The invention relates to a process to prepare said fluid, and to a hydraulic fracturation process using said fluid.

Abstract: Method of treating a portion of subterranean formation, comprising providing a water in oil emulsion of a water-soluble polymer, said emulsion comprising at least an inverting agent, and at least an emulsifying agent, wherein the mass ratio R of the total amount of inverting agent to the total amount of emulsifying agent is superior to 1.2, wherein the water in oil emulsion contains from 0.5% to 6% by weight of inverting agent; inverting the water in oil emulsion by adding it into an aqueous fluid to form an injection fluid; introducing the injection fluid into portion of the subterranean formation.

Abstract: The present invention relates to a hydrated crystalline form of 2-acrylamido-2-methylpropane sulfonic acid having a 2-theta powder X-ray diffraction diagram comprising peaks at 10.58°, 11.2°, 12.65°, 13.66°, 16.28°, 18.45°, 20°, 20.4°, 22.5°, 25.5°, 25.88°, 26.47°, 28.52°, 30.28°, 30.8°, 34.09°, 38.19°, 40.69°, 41.82°, 43.74°, 46.04° degrees (+/?0.1°). The present invention also relates to a production method for this form of 2-acrylamido-2-methylpropane sulfonic acid and a preparation method for an aqueous solution A of a salt of this form of 2-acrylamido-2-methylpropane sulfonic acid, and the (co)polymer of this form of -acrylamido-2-methylpropane sulfonic acid.

Abstract: The present invention relates to a production process for 2-acrylamido-2-methylpropane sulfonic acid including at least the following successive steps: 1) mixing of acrylonitrile with at least one compound contributing SO3 at a temperature included between ?80 and 30° C.; 2) placing in contact and mixing isobutylene and the sulfonating mixture with a molar ratio of SO3 to isobutylene included between 0.2:1 and 2:1 and a molar ratio of acrylonitrile to isobutylene included between 3:1 and 60:1 at a temperature included between ?40 and 100° C.; 3) solid/liquid separation of the reaction mixture and isolation of the solid particles in the form of a composition 1; 4) mixing composition 1 at the end of step 3) with an aqueous solution A included at a temperature comprised between ?20 and 70° C. in order to obtain a suspension 1 of 2-acrylamido-2-methylpropane sulfonic acid crystals; 5) solid/liquid separation of the suspension 1 and isolation of the crystals in form of composition 2.

Abstract: A method for diverting an underground formation comprises injecting, into the underground formation, an aqueous solution containing at least one heat-sensitive copolymer of a) at least one water-soluble monomer having at least one unsaturated function capable of being polymerized to form a water-soluble backbone, and b) at least one macromonomer of formula (I)

Abstract: Composition for preparing injection fluid in oil and gas recovery comprising an inverse emulsion of a water-soluble polymer A comprising acrylamide monomer units, and solid particles of a water-soluble polymer, wherein water-soluble polymer B is obtained by a polymerization step of at least acrylamide and 1 and 15 mol % of acrylamido tertio butyl sulfonic acid (ATBS), and/or salts thereof, and a subsequent post treatment step of the resulting polymer. Method of treating a portion of subterranean formation comprising providing said composition, preparing an injection fluid with at least said composition, introducing the injection fluid into portion of the subterranean formation. The composition is particularly useful to prepare fracturing fluid in fracturing operations.

Abstract: The present invention relates to an aqueous multiphase particulate suspension comprising a water-soluble polymer and to an enhanced oil recovery method using said suspension. The invention further relates to the use of the multiphase suspension in a drilling, hydraulic fracturing and mining effluent treatment operation.