# US 12,180,348 B2 · Rheology modification by porous gel particles > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,180,348 B2 - Document ID: US12180348B2 - Status: Granted - Kind: B2 - Application number: 17/294,659 - Filed: 2019-11-13 - Published: 2022-01-13 - Granted: 2024-12-31 - Earliest claimed: 2018-11-16 - Assignees: Energy Solutions (US) LLC - Applicants: Energy Solutions (US) LLC - Inventors: Arnaud Cadix; David James Wilson - Web page: https://patentgrep.com/patent/US12180348B2 ## CPC - C08J 9/08: developing carbon dioxide - C08F 2/24: with the aid of emulsifying agents - C08F 2/38: Polymerisation using regulators, e.g. chain terminating agents {, e.g. telomerisation} - C08F 220/1811: {C10or C11-(Meth)acrylate, e.g. isodecyl (meth)acrylate, isobornyl (meth)acrylate or 2-naphthyl (meth)acrylate} - C08F 220/56: Acrylamide; Methacrylamide - C08F 220/585: {and containing other heteroatoms, e.g. 2-acrylamido-2-methylpropane sulfonic acid [AMPS]} - C08J 3/12: Powdering or granulating - C08J 9/0033: {containing sulfur} - C08J 9/20: by suspension polymerisation in the presence of the blowing agent - C09D 4/00: Coating compositions, e.g. paints, varnishes or lacquers, based on organic non-macromolecular compounds having at least one polymerisable carbon-to-carbon unsaturated bond {; Coating compositions, based on monomers of macromolecular compounds of groups C09D183/00 - C09D183/16} - C08F 2800/20: as weight or mass percentages - C08F 2810/20: leading to a crosslinking, either explicitly or inherently - C08J 2201/026: Crosslinking before of after foaming - C08J 2203/02: CO2-releasing, e.g. NaHCO3 and citric acid - C08J 2205/02: the finished foam itself being a gel or a gel being temporarily formed when processing the foamable composition - C08J 2205/022: Hydrogel, i.e. a gel containing an aqueous composition - C08J 2333/26: Homopolymers or copolymers of acrylamide or methacrylamide - C08J: WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H (working, e.g. shaping, of plastics B29) - C08F: MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS - C09D: COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR (cosmetics A61K; processes for applying liquids or other fluent materials to surfaces, in general, B05D; staining wood B27K5/02; glazes or vitreous enamels C03C; natural resins, French polish, drying-oils, driers, turpentine, per se, C09F; polishing compositions other than French polish, ski waxes C09G; adhesives or use of materials as adhesives C09J; materials for sealing or packing joints or covers C09K3/10; materials for stopping leaks C09K3/12; processes for the electrolytic or electrophoretic production of coatings C25D) ## Abstract Modification of the rheology of a liquid medium, aqueous or nonaqueous, with polymers in the form of specific particles obtained by grinding (micronizing) a porous macrogel, itself prepared by a process comprising a radical polymerization step which comprises reacting in the presence of pore formers monomers containing monomers bearing at least two ethylenic unsaturations, typically in combination with monomers bearing a single ethylenic unsaturation; a polymerization initiator; and optionally a polymerization control agent. These polymer particles keep other particles in suspension within the liquid medium, and also the stabilized suspensions are obtained. ## Claims ### Claim 1 A method comprising adding crosslinked polymer particles (p) to a liquid medium, the crosslinked polymer particles (p) obtained by grinding a macrogel prepared by a process comprising a radical polymerization step (E) which comprises reacting, within a reaction medium M comprising pore formers: ethylenically unsaturated monomers, containing monomers m1 bearing at least two ethylenic unsaturations; at least one radical polymerization initiator; optionally at least one radical polymerization control agent to modify the rheology of said liquid medium, wherein: the crosslinked polymer particles (p) have in a dry state, an average diameter ranging between 0.5 to 250 microns when measured using a sieve; and the macrogel has an average pore size greater than or equal to 500 nm. ### Claim 2 (depends on 1) The method as claimed in claim 1, wherein the monomers employed in step (E) further comprise monomers m2 bearing a single ethylenic unsaturation. ### Claim 3 (depends on 1) The method as claimed in claim 1, wherein the liquid medium is an aqueous liquid medium. ### Claim 4 (depends on 1) The method as claimed in claim 1, wherein particles are kept in suspension within the liquid medium. ### Claim 5 (depends on 1) The method as claimed in claim 1, wherein the pore formers employed in step (E) are gas bubbles. ### Claim 6 (depends on 1) The method as claimed in claim 1, wherein step (E) first comprises a step (E1) in which only a part of the ethylenically unsaturated monomers are polymerized in the absence of pore formers, then a step (E2) in which the polymerization is continued with introduction of the pore formers. ### Claim 7 (depends on 1) The method as claimed in claim 1, wherein step (E) is a controlled radical polymerization conducted in the presence of a radical polymerization control agent. ### Claim 8 (depends on 5) The method as claimed in claim 5, wherein the pore formers employed in step (E) are CO2 bubbles formed by reaction of a bicarbonate with an acidic compound present in the reaction medium. ### Claim 9 (depends on 7) The method as claimed in claim 7, wherein the radical polymerization control agent is a compound bearing a thiocarbonylthio group —S(C═S)—. ### Claim 10 (depends on 2) The method as claimed in claim 2, wherein the mass ratio m1/m2 is between 0.01 and 30.