US5236965A
Expired / Lapsed
US
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Hydrophilic, swellable polymers
Assignee: Sanofi Aventis Deutschland GmbH
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Filing: 1993-01-19
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Granted: 1993-08-17
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Expires: 2013-01-19
Abstract
Abstract The present invention relates to hydrophilic, swellable polymers which consist of radicals of the general formula I ##STR1## wherein R 1 to R 3 are defined as stated in the description, and of radicals of a crosslinking agent which have originated from monomers having at least two olefinically unsaturated double bonds, and which are characterized in that they are in the form of a highly porous, foam-like polyhedral structure, their preparation and their use as absorption agents for water and aqueous solutions.
Inventors
- 👤 Friedrich Engelhardt
- 👤 Gerlinde Ebert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 09:56
CPC Classifications
A; A61; A61L; A61L15/00; A61L15/16; A61L15/42; A61L15/425; A61L15/60; C; C08; C08F; C08F2/00; C08F2/04; C08F2/06; C08F2/08; C08F20/00; C08F20/02; C08F20/04; Y; Y10; Y10S; Y10S604/00; Y10S604/904
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
106 words
Hydrophilic, swellable polymer which consists in random distribution, to the extent of 98 to 100% by weight of radicals of the general formula I ##STR7## wherein R 1 denotes hydrogen, methyl or ethyl, R 2 denotes phenyl, sulphonylphenyl, pyrrolidonyl, pyridyl or imidazolyl and R 3 denotes hydrogen, methyl, ethyl or carboxyl, it also being possible for acid groups to be present in salt form, and to the extent of 0-2% by weight of radicals of a crosslinking agent which having originated from monomers having at least two olefinically unsaturated double bonds, characterized in that it is in the form of a highly porous, foam-like polyhedral structure.
Claim 2
Dependent Claim
106 words
Hydrophilic, swellable polymer which consists in random distribution, to the extent of 98 to 100% by weight of radicals of the general formula I ##STR7## wherein R 1 denotes hydrogen, methyl or ethyl, R 2 denotes phenyl, sulphonylphenyl, pyrrolidonyl, pyridyl or imidazolyl and R 3 denotes hydrogen, methyl, ethyl or carboxyl, it also being possible for acid groups to be present in salt form, and to the extent of 0-2% by weight of radicals of a crosslinking agent which having originated from monomers having at least two olefinically unsaturated double bonds, characterized in that it is in the form of a highly porous, foam-like polyhedral structure.
Claim 3
Dependent Claim
21 words
Polymer according to claim 1, characterized in that the polyhedral structure has an average pore diameter of 0.8 to 1.2 mm.
Claim 4
Dependent Claim
39 words
Polymer according to claim 1, characterized in that it consists to the extent of 98.5 to 99.7% by weight of radicals of the general formula I and to the extent of 0.3 to 1.5% by weight of crosslinking structures.
Claim 5
Dependent Claim
24 words
Polymer according to claim 1, characterized in that in the general formula I, R 1 denotes hydrogen or methyl and R 3 denotes hydrogen.
Claim 6
Dependent Claim
20 words
Polymer according to claim 1, characterized in that the radicals of a crosslinking agent are derived from methyl-bisacrylamide or N,N'-dihydroxyethylene-bisacrylamide.
Claim 7
Dependent Claim
90 words
Process for the preparation of hydrophilic, swellable polymers according to claim 1 by polymerization of 98 to 100% by weight, of a compound of the general formula Ia ##STR8## wherein R 1 , R 2 and R 3 are as defined in claim 1, or a salt thereof, with 0 to 2% by weight, of a monomer having at least two olefinically unsaturated double bond, characterized in that an aqueous matrix containing a surfactant and the monomers and stabilized by a liquid hydrocarbon phase is employed as the polymerization medium.
Claim 8
Dependent Claim
42 words
Process according to claim 6, characterized in that the polymerization medium consists of 50 to 99.5% by weight of hydrocarbon, 0.2 to 20% by weight of monomer, 0.1 to 5% by weight, of surfactant and 0.2 to 25% by weight, of water.
Claim 9
Dependent Claim
42 words
Process according to claim 6, characterized in that the polymerization medium consists of 60 to 99% by weight of hydrocarbon, 0.4 to 16% by weight of monomer, 0.1 to 4% by weight of surfactant and 0.5 to 20% by weight of water.
Claim 10
Dependent Claim
33 words
Process according to claim 6, characterized in that n-Pentane, n-hexane, n-heptane, n-octane, n-nonane, n-decane, n-dodecane, n-tetradecane, n-hexadecane, cyclohexane, cyclooctane, benzene, toluene, kerosine, petrol, lead-free petrol or diesel oil is employed as the hydrocarbon.
Claim 11
Dependent Claim
15 words
Process according to claim 6, characterized in that sodium dodecylsulphate is employed as the surfactant.
Claim 12
Dependent Claim
14 words
A hygienic article which has been impregnated with the swellable polymer of claim 1.
Claim 13
Dependent Claim
19 words
The hygienic article of claim 11 wherein the hygienic article is a nappy, a tampon or a sanitary towel.
Claim 14
Dependent Claim
19 words
Polymer according to claim 1, wherein the density of the polymer is between 0.01 and 0.05 g/cm 3 .
References Cited (Backward Citations)
FR1082268A
Cited
US3886125A
Cited
US4190713A
Cited
US4222415A
Cited
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Cited
US4535098A
Cited
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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) | 1996-08-16 | 1997-02-15 | 1997-08-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-08-16 | 2001-02-15 | 2001-08-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-08-16 | 2005-02-15 | 2005-08-17 | $7700.00 | Window Closed / Lapsed |