Abstract: Process for preparing water-soluble polymers in powder form by polymerization of water-soluble monoethylenically unsaturated monomers comprising the successive steps: a) Spraying on the inner wall of a polymerization vessel, the lubricant composition LC1: alkyl oleate/polyoxyethylene oleyl ether phosphate/sorbitan monolaurate, b) Polymerizing in aqueous solution in the presence of polymerization initiators at least one water-soluble monounsaturated ethylenic monomer, c) Discharging the polymer gel, d) Granulating the polymer gel thus obtained in a granulator, in presence of a lubricant composition LC2: alkyl oleate/polyxoyethylene oleyl ether phosphate/sorbitan monol aurate, e) Drying the polymer gel to obtain a polymer in powder form, f) Grinding and sifting the powder.

Abstract: The present application concerns a water-in-oil inverse emulsion comprising: oil; water; at least one water-soluble anionic polymer of average molecular weight higher than 3 million daltons, containing between 4 and 14 mol % of sulfonated anionic monomers, between 0 and 17 mol % of carboxylated anionic monomers and between 69 and 94 mol of nonionic monomers; at least one inverting agent and at least one emulsifying agent, the weight ratio R between the total amount of inverting agent and the total amount of emulsifying agent being higher than 1.

Abstract: The invention relates to an inverse polymer emulsion having the particular feature of auto-inverting without any need for the use of an inverting agent and containing a polymer of at least one water-soluble monomer and at least one LCST macromonomer. The invention also relates to the use of the inverse emulsion in the fields of the oil and gas industry, water treatment, slurry treatment, paper manufacturing, construction, mining, cosmetics, textiles, detergents or agriculture.

Abstract: This invention relates to a process of enhanced oil recovery by sweeping an underground formation comprising injecting into the underground formation an injection fluid comprising at least one water-soluble LCST macromonomeric polymer.

Abstract: Fracturing fluid comprising, in solution in water, a proppant and an associative amphoteric polymer, the said polymer and comprising: 0.01 to 10 mol % of at least one cationic monomer containing a hydrophobic chain, from 0.09 to 89.99 mol % of at least one anionic monomer, and from 10 to 99.9 mol % of at least one nonionic water-soluble monomer, the total amount of monomer being 100 mol %. Fracturing process using this fluid.

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 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: Process for the production of anionic water-soluble polymer obtained by the polymerization of acrylic acid and acrylamide obtained by biocatalysed reaction, said process comprising the steps of preparing a diluted solution of acrylic acid by mixing acrylic acid and water wherein the mass ratio between acrylic acid and water is comprised between 95:5 and 70:30, preparing a diluted solution of bioacrylamide and water wherein the mass ratio between bioacrylamide and water is comprised between 60:40 and 10:90, mixing said diluted solution of acrylic acid with said diluted solution of bioacrylamide, neutralizing partially or totally the acid function of acrylic acid and polymerizing the resulting mixture.

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: This invention relates to a method for preparing a structured water-soluble polymer having a weight average molecular weight greater than 1 million Daltons and a Huggins Coefficient KH greater than 0.4, the method comprising the following successive steps: a) Preparing a polymer, in the form of a gel, by free-radical polymerization in aqueous solution at an initiation temperature between ?20° C. and +50° C.

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 the treatment of mine tailings in the form aqueous effluents comprising solid particles. With the process of the invention it is possible to separate all or part of the water from an aqueous effluent comprising solid particles. This process comprises (a) adding to the effluent at least one anionic modified natural polymer selected from among anionic guar gums and/or anionic starches, then (b) adding at least one cationic modified natural polymer selected from among cationic starches and/or cationic dextrans and/or cationic chitosans. The invention also relates to a composition comprising an aqueous effluent comprising solid particles treated with an anionic modified natural polymer and a cationic modified natural polymer.

Abstract: A continuous process for filtering a suspension of 2-acrylamido-2-methylpropane sulfonic acid crystals by means of a rotary pressure filter equipped with a drum, a surface of which is provided with cells covered with a filter medium, the drum rotating within a fixed concentric cylinder comprising at least three zones sealed from each other, respectively a filtration zone, a washing zone and a discharge zone, each zone opening onto the cells.

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: 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 application relates to a water-in-oil reverse emulsion comprising an oil; water; at least one water-soluble cationic copolymer with an average molar mass of more than 3 million daltons, containing between 18 and 32 mole % of cationic monomers and 68 and 82 mole of nonionic monomers; at least one reversing agent and at least one emulsifying agent, the weight ratio R of the total amount of reversing agent to the total amount of emulsifying agent being greater than 1.8, the reversing agent being selected from an ethoxylated nonylphenol, preferably having between 4 and 10 ethoxylations; an ethoxylated/propoxylated alcohol, preferably having ethoxylations/propoxylations so as to have a total carbon number between C12 and C25, an ethoxylated tridecyl alcohol and an ethoxylated/propoxylated fatty alcohol. the emulsifying agent being selected from sorbitan monooleate, polyethoxylated sorbitan esters or diethanolamide of tall oil fatty acids, and its use in hydraulic fracturing.

Abstract: The present invention relates to a method for modifying the water permeability of a subterranean formation which comprises oil, said method comprising at least the following steps: Preparing an injection fluid from a dispersion of a hydrophilic phase in a lipophilic phase, with water or brine, the dispersion comprising: a hydrophilic phase comprising at least one linear (co)polymer E, a lipophilic phase, at least one interface polymer composed of at least one monomer of formula (I): Injecting the injection fluid into the subterranean formation, comprising a linear (co)polymer E concentration, such that when released and in contact with water, the viscosity of the injection fluid is greater than the viscosity of the oil in the formation.

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 invention relates to a method for the purification of acrylamido-2-methyl-2-propanesulphonic acid comprising the following successive steps: 1) preparation of a suspension of acrylamido-2-methyl-2-propanesulphonic acid crystals by distillation of an aqueous solution of acrylamido-2-methyl-2-propanesulphonic acid in order to obtain a suspension of acrylamido-2-methyl-2-propanesulphonic acid crystals, 2) isolation of the acrylamido-2-methyl-2-propanesulphonic acid crystals generally by solid/liquid separation from said suspension in order to isolate said acrylamido-2-methyl-2-propanesulphonic acid crystals, characterised in that the distillation step is carried out continuously and at a pressure below atmospheric pressure.

Abstract: The present invention relates to a method for determining the anionic charge density of at least one polymer present in a sample, according to the following steps: bringing the at least one polymer present in the sample into contact with, and enabling the interaction thereof with, a developer solution comprising lanthanide (III) ions, exciting the sample at an excitation wavelength ?exc and detecting, by time-resolved photoluminescence, a signal originating from the lanthanide (III) ions that have interacted with the at least one polymer at an emission wavelength ?em, and determining the anionic charge density of the at least one polymer of the sample using the signal detected at the emission wavelength ?em.