US4748220A
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US
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Preparation of finely divided pulverulent crosslinked copolymers
Assignee: BASF SE
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Filing: 1987-03-20
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Granted: 1988-05-31
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Expires: 2007-03-20
Abstract
Abstract Pulverulent crosslinked copolymers are prepared by polymerizing monomer mixtures consisting of (a) from 70 to 99.99% by weight of monoethylenically unsaturated carboxylic acids, their amides and/or esters of such carboxylic acids and aminoalcohols, (b) from 0.001 to 10% by weight of a diethylenically or polyethylenically unsaturated monomer and (c) from 0 to 20% by weight of other monoethylenically unsaturated monomers in supercritical carbon dioxide under superatmospheric pressure in the presence of a free radical initiator.
Inventors
- 👤 Heinrich Hartmann
- 👤 Walter Denzinger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 15:27
CPC Classifications
C; C08; C08F; C08F220/00; C08F220/02; C08F220/52; C08F220/54; A; A61; A61K; A61K47/00; A61K47/30; A61K47/32; A61K8/00; A61K8/18; A61K8/72; A61K8/81; A61K8/8141; A61K8/8147; A61K8/8152; A61K8/8158; A61Q; A61Q19/00; C08F220/04; Y; Y02; Y02P; Y02P20/00; Y02P20/50; Y02P20/54; Y10; Y10S; Y10S526/00; Y10S526/942
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
177 words
A process for the preparation of a pulverulent crosslinked copolymer, comprising polymerizing a monomer mixture consisting of (a) from 70 to 99.999% by weight of monoethylenically unsaturated carboxylic acids, amides of such carboxylic acids and/or esters of such carboxylic acids and amino alcohols of the formula ##STR3## where R is C 2 -C 6 -alkylene and R 1 and R 2 are each H, CH 3 , C 2 H 5 or C 3 H 7 , (b) from 0.001 to 10% by weight of a diethylenically or polyethylenically unsaturated monomer and (c) from 0 to 20% by weight of other monoethylenically unsaturated monomers in supercritical carbon dioxide at up to 150° C. and under pressures above 73 bar in the presence of a free radical initiator, from 100 to 1,500 parts by weight of carbon dioxide being used per 100 parts by weight of the monomers employed in the polymerization, and removing the carbon dioxide after the polymerization resulting in a fine polymer powder consisting of primary particles of 0.5 μm to 3 μm in diameter.
Claim 2
Dependent Claim
177 words
A process for the preparation of a pulverulent crosslinked copolymer, comprising polymerizing a monomer mixture consisting of (a) from 70 to 99.999% by weight of monoethylenically unsaturated carboxylic acids, amides of such carboxylic acids and/or esters of such carboxylic acids and amino alcohols of the formula ##STR3## where R is C 2 -C 6 -alkylene and R 1 and R 2 are each H, CH 3 , C 2 H 5 or C 3 H 7 , (b) from 0.001 to 10% by weight of a diethylenically or polyethylenically unsaturated monomer and (c) from 0 to 20% by weight of other monoethylenically unsaturated monomers in supercritical carbon dioxide at up to 150° C. and under pressures above 73 bar in the presence of a free radical initiator, from 100 to 1,500 parts by weight of carbon dioxide being used per 100 parts by weight of the monomers employed in the polymerization, and removing the carbon dioxide after the polymerization resulting in a fine polymer powder consisting of primary particles of 0.5 μm to 3 μm in diameter.
Claim 3
Dependent Claim
28 words
A process as claimed in claim 1, wherein from 200 to 900 parts by weight of carbon dioxide are used per 100 parts by weight of the monomers.
Claim 4
Dependent Claim
114 words
A process as claimed in claim 1, wherein (a) monoethylenically unsaturated C 3 -C 5 -carboxylic acids, amides of ethylenically unsaturated C 3 -C 5 -carboxylic acids and/or di-C 1 -C 3 -alkylamino-C 2 -C 6 -alkyl acrylates or methacrylates in the form of the salts or in quaternizied form, (b) divinyldioxane, polyalkyl and polyvinyl ethers of mono-, di- and oligosaccharides, N,N'-methylenebisacrylamide, N,N'-methylenebismethacrylamide, di- and triallyl ethers of trimethylolpropane and glycerol, and pentaerythritol triallyl ether, and (c) acrylonitrile, methacrylonitrile, acrylates and methacrylates of monohydric C 1 -C 18 -alcohols, hydroxy-C 2 -C 4 -alkyl esters of acrylic acid and methacrylic acid, maleic anhydride, vinyl esters and/or vinylphosphonic acid are used as the monomer mixture.
Claim 5
Dependent Claim
93 words
A process as claimed in claim 1, wherein (a) from 70 to 99.95% by weight of acrylic acid, methacrylic acid, acrylamide and/or methacrylamide, (b) from 0.05 to 5% by weight of divinyldioxane, di-, tri-, tetra- and pentaallyl sucrose or mixtures of these, pentaerythritol triallyl ether or N,N'-methylenebisacrylamide and/or (c) from 0 to 20% by weight of acrylates and methacrylates of monohydric C 1 -C 18 -alcohols, hydroxy-C 2 -C 4 -alkyl esters of acrylic acid and methacrylic acid, maleic anhydride, vinyl acetate, vinyl propionate and/or vinylphosphonic acid are used as the monomer mixture.
Claim 6
Dependent Claim
27 words
A process as claimed in claim 1, wherein (a) acrylic acid or methacrylic acid and (b) pentaerythritol triallyl ether or N,N'-methylenebisacrylamide are used as the monomer mixture.
Claim 7
Dependent Claim
23 words
A process as claimed in claim 1, wherein tert.butyl per-2-ethylhexanoate, 2,2'-azobis-(2,4-dimethylvaleronitrile), 2,2'-asobis-(4-methoxy-2,4-dimethylvaleronitrile), 2,2'-azobis-isobutyronitrile or 2,2'-azobis-(2-amidinopropane) dihydrochloride is used as the free radical initiator.
References Cited (Backward Citations)
US29231A
Cited
FR753433A
Cited
US3040012A
Cited
US3522228A
Cited
USRE29231E
Cited
US4052343A
Cited
US4418175A
Cited
US4486489A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-05-31 | 1991-11-30 | 1992-05-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-05-31 | 1995-11-30 | 1996-05-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-05-31 | 1999-11-30 | 2000-05-31 | $7700.00 | Window Closed / Lapsed |