# US 2014/0194563 A1 · Process for preparing an aqueous polymer dispersion under vacuum, and uses thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0194563 A1 - Document ID: US20140194563A1 - Status: Published application - Kind: A1 - Application number: 14/053,995 - Filed: 2013-10-15 - Published: 2014-07-10 - Earliest claimed: 2013-01-09 - Assignees: S.P.C.M. SA - Applicants: S.P.C.M. SA - Inventors: Sebastien COCCOLO; Bruno TAVERNIER - Web page: https://patentgrep.com/patent/US20140194563A1 ## CPC - C08F 2/20: with the aid of macromolecular dispersing agents - C08F 220/06: Acrylic acid; Methacrylic acid; Metal salts or ammonium salts thereof - C08F 220/56: Acrylamide; Methacrylamide - C08L 33/02: Homopolymers or copolymers of acids; Metal or ammonium salts thereof - C08L 33/26: Homopolymers or copolymers of acrylamide or methacrylamide - C08F: MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS - C08L: COMPOSITIONS OF MACROMOLECULAR COMPOUNDS (compositions based on polymerisable monomers C08F, C08G; artificial filaments or fibres D01F; textile treating compositions D06) ## Abstract Process for preparing an aqueous dispersion of hydrophilic polymers, according to which, in a reactor: a reaction medium is prepared in the form of an aqueous solution comprising water-soluble monomers, one or more salts and/or one or more dispersant organic polymers; the monomers are polymerized; the polymer obtained is discharged from the reactor; wherein the pressure of the reaction medium is lowered to a value below 200 mbar. ## Claims ### Claim at position 1 1/ A process for preparing an aqueous dispersion of hydrophilic polymers, according to which, in a reactor: a reaction medium is prepared in the form of an aqueous solution comprising at least water-soluble monomers, one or more salts and/or one or more dispersing organic polymers; the monomers are polymerized; the polymer obtained is discharged from the reactor; wherein the pressure of the reaction medium is lowered to a value below 200 mbar. ### Claim at position 2 (depends on 1) 2/ The process as claimed in claim 1, wherein the pressure of the reaction medium is lowered to a value such that the reaction medium boils. ### Claim at position 3 (depends on 1) 3/ The process as claimed in claim 1, wherein the pressure of the reaction medium is lowered to a value of between 0.1 mbar and 100 mbar. ### Claim at position 4 (depends on 1) 4/ The process as claimed in claim 1, wherein the reaction medium is prepared at atmospheric pressure, and the pressure of said reaction medium is lowered throughout all or part of the duration of the polymerization. ### Claim at position 5 (depends on 1) 5/ The process as claimed in claim 1, wherein the following are successively performed: the reaction medium is prepared at atmospheric pressure, the pressure of said reaction medium is lowered, and the polymerization is initiated. ### Claim at position 6 (depends on 1) 6/ The process as claimed in claim 1, wherein the following are successively performed: the reaction medium is prepared at atmospheric pressure, simultaneously, the pressure of said reaction medium is lowered and the polymerization is initiated. ### Claim at position 7 (depends on 1) 7/ The process as claimed in claim 1, wherein the following are successively performed: the reaction medium is prepared at atmospheric pressure, the polymerization is initiated, and the pressure of said reaction medium is lowered throughout the polymerization. ### Claim at position 8 (depends on 1) 8/ The process as claimed in claim 1, wherein the polymerization temperature is between 10 and 80° C. ### Claim at position 9 (depends on 1) 9/ The process as claimed in claim 1, wherein the water-soluble monomers contain an ethylenic double bond and are chosen from the following families: anionic monomers chosen from the group consisting of monomers bearing a carboxylic function, monomers bearing a sulfonic acid function, and salts thereof; nonionic monomers chosen from the group consisting of acrylamide and methacrylamide, acrylamide derivatives, vinylformamide, N-vinylpyridine, N-vinylpyrrolidone, hydroxyalkyl acrylates and methacrylates, and (meth)acrylates bearing chains of the alkoxy type; cationic polymers chosen from the group consisting of diallyldialkylammonium salts, dialkylaminoalkyl acrylates and methacrylates, and also the acidified or quaternized forms thereof, and dialkylaminoalkyl-acrylamides or -methacrylamides, and also the acidified or quaternized forms thereof. ### Claim at position 10 (depends on 1) 10/ The process as claimed in claim 1, wherein the monomer concentration in the aqueous solution is generally between 5% and 50% by weight. ### Claim at position 11 (depends on 1) 11/ The process as claimed in claim 1, wherein the salt(s) are chosen from those comprising sulfate, dihydrogen phosphate, phosphate and halide anions, and comprising sodium, potassium, ammonium, magnesium or aluminum as the corresponding cations. ### Claim at position 12 (depends on 1) 12/ The process as claimed in claim 1, wherein the salt concentration in the aqueous solution corresponds at most to the maximum salt solubility. ### Claim at position 13 (depends on 1) 13/ The process as claimed in claim 1, wherein the dispersing organic polymer(s) are polymers with a molecular weight of between 1000 and 500 000 g/mol. ### Claim at position 14 (depends on 1) 14/ The process as claimed in claim 1, wherein the concentration of dispersing organic polymer in the aqueous phase is generally less than 30% by. ### Claim at position 15 (depends on 1) 15/ The process of claim 1, further comprising use of the aqueous dispersion of hydrophilic polymer obtained via the process in at least one of the following industries: paper industry, water treatment), coagulation or flocculation techniques, mining industry, petroleum industry, cosmetic products industry, textile industry, and detergent products industry. ### Claim 16 (depends on 1) The process as claimed in claim 1, wherein the pressure of the reaction medium is lowered to a value of between 1 mbar and 60 mbar. ### Claim 17 (depends on 1) The process as claimed in claim 1, wherein the polymerization temperature between 20 and 40° C. ### Claim 18 (depends on 1) The process as claimed in claim 1, wherein the monomer concentration in the aqueous solution is generally between 15% and 35% by weight. ### Claim 19 (depends on 1) The process as claimed in claim 1, wherein the salt concentration in the aqueous solution corresponds to between 5% and 35% by weight. ### Claim 20 (depends on 1) The process as claimed in claim 1, wherein the salt concentration in the aqueous solution corresponds to between 8% and 27% by weight. ### Claim 21 (depends on 1) The process as claimed in claim 1, wherein the concentration of dispersing organic polymer in the aqueous phase is between 5% and 20% by weight.