Patent US3834381A successfully refreshed from Google Patents.
US4049604A
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Emulsion polymerization method for preparing aqueous dispersions of organic polymer particles
Assignee: Dow Chemical Co
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Filing: 1970-06-08
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Granted: 1977-09-20
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Expires: 1990-06-08
Abstract
Abstract Aqueous dispersions of normally solid, organic polymeric particles are prepared by (1) dispensing an oil phase containing at least one emulsion polymerizable monomer such as styrene in an aqueous phase containing a stabilizing emulsifier such as sodium dodecyl benzene sulfonate and a polymer of a sulfo ester of an α,β-ethylenically unsaturated carboxylic acid such as a 2-sulfoethyl methacrylate n-butyl acrylate copolymer and (2) subjecting the dispersion to emulsion polymerization. Microspheres having liquid centers and seamless rigid walls of a normally solid, organic polymer are prepared according to the above method except that the starting oil phase also contains a non-polymerizable, water-insoluble liquid such as hexane.
Inventors
- 👤 Donald S. Morehouse, Jr.
- 👤 Frank Harold Bolton, deceased
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 23:21
CPC Classifications
C; C08; C08F; C08F2/00; C08F2/12; C08F2/16; C08F2/22; C08F2/24; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2982; Y10T428/2984; Y10T428/2985; Y10T428/2987; Y10T428/31504; Y10T428/31855; Y10T428/31909; Y10T428/31928
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
167 words
An emulsion polymerization method for preparing an aqueous dispersion of normally solid organic polymeric particles, said method comprising dispersing an oil phase comprising at least one monovinylidene aromatic carbocyclic monomer in an aqueous phase containing from about 0.5 to about 4 weight percent based on total monomer of a stabilizing emulsifier selected from the group consisting of water-soluble anionic surfactant, water-soluble non-ionic surfactants and mixtures thereof, and from about 0.2 to about 2 weight percent based on total monomer of a polymer of at least 20 weight percent of a sulfo ester of an α-methylene carboxylic acid and up to 80 weight percent of at least one ethylenically unsaturated monomer copolymerizable therewith selected from a group consisting of monovinylidene aromatic carbocyclic monomer, acrylate esters and acrylonitriles, said total monomer being capable of polymerization to form a water-insoluble polymer, and (2) subjecting the dispersion to emulsion polymerization conditions comprising free-radical type catalyst, temperature in the range from about 60° to about 100° C. and agitation of the dispersion.
Claim 2
Dependent Claim
167 words
An emulsion polymerization method for preparing an aqueous dispersion of normally solid organic polymeric particles, said method comprising dispersing an oil phase comprising at least one monovinylidene aromatic carbocyclic monomer in an aqueous phase containing from about 0.5 to about 4 weight percent based on total monomer of a stabilizing emulsifier selected from the group consisting of water-soluble anionic surfactant, water-soluble non-ionic surfactants and mixtures thereof, and from about 0.2 to about 2 weight percent based on total monomer of a polymer of at least 20 weight percent of a sulfo ester of an α-methylene carboxylic acid and up to 80 weight percent of at least one ethylenically unsaturated monomer copolymerizable therewith selected from a group consisting of monovinylidene aromatic carbocyclic monomer, acrylate esters and acrylonitriles, said total monomer being capable of polymerization to form a water-insoluble polymer, and (2) subjecting the dispersion to emulsion polymerization conditions comprising free-radical type catalyst, temperature in the range from about 60° to about 100° C. and agitation of the dispersion.
Claim 3
Dependent Claim
20 words
The method according to claim 1 wherein the sulfo ester copolymer is a copolymer of 2-sulfoethyl methacrylate and butyl acrylate.
Claim 4
Dependent Claim
211 words
The method according to claim 1 comprising 1. dispersing an oil phase comprising at least one emulsion polymerizable, ethylenically unsaturated monomer selected from the group consisting of monovinylidene aromatic carbocyclic compounds, alkyl acrylates and acrylonitriles and remaining monomer consisting essentially of up to about 10 weight percent of an ethylenically unsaturated monomers selected from the group consisting of α, β-ethylenically unsaturated carboxylic acids, divinyl benzene, 2-hydroxyethyl acrylate and 2-sulfoethyl acrylate in an aqueous phase containing from about 0.5 to about 4 weight percent based on total monomer of a stablizing emulsifier selected from the group consisting of water-soluble, anionic and non-ionic surfactants and mixtures thereof and from about 0.2 to about 2 weight percent based on total monomer of a polymer of at least 20 weight percent sulfo ester of an α-methylene carboxylic acid and up to 80 weight percent of an ethylenically unsaturated monomer selected from the group consisting of monovinylidene aromatic carbocyclic compounds, esters of ethylenically unsaturated carboxylic acids, acrylonitriles, unsaturated alcohol esters, unsaturated ketones and unsaturated ethers containing one or more ethylenic linkages capable of addition polymerization, and 2. subjecting the dispersion to emulsion polymerization conditions of initiation by using a free radical type catalyst at temperature from about 60° to about 100° C. and agitating the dispersion.
Claim 5
Dependent Claim
29 words
The method according to claim 3 wherein the emulsifier is an anionic emulsifier and the sulfo ester polymer is a copolymer of the sulfo ester and an alkyl acrylate.
Claim 6
Dependent Claim
20 words
The method according to claim 4 wherein the sulfo ester is 2-sulfoethyl methacrylate and the alkyl acrylate is n-butyl acrylate.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-09-19 | 1981-03-21 | 1981-09-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-09-19 | 1985-03-21 | 1985-09-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-09-19 | 1989-03-21 | 1989-09-20 | $7700.00 | Window Closed / Lapsed |