# US 7,745,533 B2 · Manufacture of stable low particle size organopolysiloxane emulsion > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,745,533 B2 - Document ID: US7745533B2 - Status: Granted - Kind: B2 - Application number: 11/832,278 - Filed: 2007-08-01 - Published: 2007-11-29 - Granted: 2010-06-29 - Earliest claimed: 2005-02-02 - Assignees: Wacker Chemie AG - Inventors: Amit Kumar Paul - Web page: https://patentgrep.com/patent/US7745533B2 ## CPC - C08J 3/03: in aqueous media - C08G 77/06: Preparatory processes - C08J 2383/04: Polysiloxanes - 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) - C08G: MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS ## Abstract Stable high viscosity organopolysiloxane emulsions with particle sizes up to 150 nanometer may be made in a simple and cost-effective manner employing a standard homogenizer, and optional subsequent polymerization of the organopolysiloxan at controlled temperature. A combination of non-ionic emulsifier together with an at least one anionic emulsifier is employed, having an HLB value 12-15, while maintaining a temperature up to 50° C. ## Claims ### Claim 1 A process for the manufacture of a stable aqueous organopolysiloxane emulsion having a particle size (D50 value) up to 150 nanometers, comprising: i) providing a formulation comprising (a) an organopolysiloxane of the formula I: where R1 is hydroxyl group or a C1-8 alkoxy group, and where R, which are the same or different, are monovalent hydrocarbon radicals, and x is an integer from 1 to 100 or mixtures thereof in an amount of 20 to 80% by. wt. (b) water in an amount of 5 to 30% by wt. (c) non-ionic emulsifier(s) having an HLB in the range of 10-19 in amounts of 1 to 25% by wt. and (d) at least one anionic emulsifier selected from organic sulfonic acids having an HLB in the range of 8-19 in an amount of 1 to 15% by. wt.; ii) homogenizing the formulation of (i) while maintaining a temperature in the range of 10°C to 40°C so as to increase organopolysiloane polymer growth rate or rise in polymer viscosity to at least 20,000 mPa-s, and iii) neutralising the emulsion by alkali to a pH range of 6-8. ### Claim 2 (depends on 1) The process of claim 1 wherein the emulsifier or mixture of emulsifiers have an HLB value in the range of 12-15. ### Claim 3 (depends on 1) The process of claim 1 comprising: (i) providing 8 to 30% of mixed emulsifiers comprising at least one anionic emulsifier selected from the group consisting of organic sulfonic acids and at least one non-ionic emulsifier having an HLB value in the range of 10-19; (ii) homogenising the formulation while maintaining a temperature in the range of 20°C to 40°C, for a period of 10 minutes to 2 hr; (iii) allowing the emulsion to age in the range of 5 to 30° C. wherein the viscosity of an internal phase oil increases to at least 20,000 mPa-s; (iv) neutralising the emulsion with alkali, and adding biocide. ### Claim 4 (depends on 1) The process of claim 1, wherein for an internal oil viscosity of less than 500,000 cps, neutralizing of the emulsion is carried out immediately after completion of mixing. ### Claim 5 (depends on 1) The process of claim 1, wherein the organopolysiloxane of the formula (I) is selected from the group consisting of alpha, omega hydroxyl-terminated organopolysiloxanes; alpha, omega alkoxy-terminated organopolysiloxanes; and mixtures thereof. ### Claim 6 (depends on 1) The process of claim 1, wherein a branched polysiloxane emulsion is formed, comprising adding a tri-functional or tetra-functional silane or mixture thereof with the organopolysiloxane(s). ### Claim 7 (depends on 1) The process of claim 1, wherein the anionic surfactant is selected from the group consisting of alkylaryl sulfonic acid; alkylaryl polyoxyethylene sulphonic acid; alkyl sulfonic acid, alkyl polyoxyethylene sulfonic acid, and mixtures thereof. ### Claim 8 (depends on 7) The process of claim 7, wherein the sulfonic acids comprise: R2C6H4SO3H (V) R2C6H4O(C2H4O)mSO3H (VI) R2SO3H (VII) R2O(C2H4O)mSO3H (VIII) where R2 each individually is a monovalent hydrocarbon radical having at least 6 carbon atoms, and m is an integer from 1 to 25. ### Claim 9 (depends on 8) The process of claim 8, where R2 individually are selected from the group consisting of hexyl, octyl, decyl, dodecyl, cetyl, stearyl, myristyl, and oleyl. ### Claim 10 (depends on 1) The process of claim 1, wherein the anionic surfactant(s) is used in amounts of 1-15% and are selected from the group consisting of octyl benzene sulfonic acid; dodecylbenzene sulfonic acid; cetylbenzene sulfonic acid; alpha-octyl sulfonic acid; alpha-dodecyl sulfonic acid; alpha-cetyl sulfonic acid; polyoxyethylene octyl-benzene sulfonic acid; polyoxyethylene-dodecyl benzene sulfonic acid; polyoxyethylene cetyl-benzene sulfonic acid; polyoxyethylene octyl sulfonic acid; polyoxyethylene dodecyl sulfonic acid, polyoxyethylene cetyl sulfonic acid, and mixtures thereof. ### Claim 11 (depends on 1) The process of claim 1, wherein said non-ionic emulsifiers comprise non-ionic surfactants in an amount of 1 to 25%, selected from the group consisting of polyoxyalkylene alkyl ethers, polyoxyalkylene alkylphenyl ethers, and polyoxyalkylene sorbitan esters. ### Claim 12 (depends on 11) The process of claim 11, wherein the nonionic emulsifier is selected from the group consisting of polyethylene glycol octyl ether; polyethylene glycol lauryl ether; polyethylene glycol tridecyl ether; polyethylene glycol cetyl ether; polyethylene glycol stearyl ether; polyethylene glycol nonylphenyl ether; polyethylene glycol dodecylphenyl ether; polyethylene glycol cetylphenyl ether; polyethylene glycol staerylphenyl ether; polyethylene glycol sorbitan mono stearate, polyethylene glycol sorbitan mono oleate, and mixtures thereof.