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US5034488A
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Slurry polymerization of crosslinked maleic anhydride-alkyl vinyl ether copolymers in a solvent system comprising a carboxylic acid ester and a saturated hydrocarbon
Assignee: ISP CAPITAL Inc
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Filing: 1990-01-11
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Granted: 1991-07-23
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Expires: 2010-01-11
Abstract
Abstract A polymerization process is described herein for making crosslinked copolymers of maleic anhydride and an alkyl vinyl ether characterized in that polymerization is carried out in a solvent system which is a mixture of a carboxylic acid ester and a saturated hydrocarbon, preferably a mixture of ethyl acetate and cyclohexane in the weight ratio of about 35% to 55% ethyl acetate and 45% to 65% cyclohexane.
Inventors
- 👤 Mohammed Tazi
- 👤 Yoon T. Kwak
- 👤 Robert B. Login
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 12:25
CPC Classifications
C; C08; C08F; C08F222/00; C08F222/04; C08F222/06
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
48 words
In a polymerization process for making a crosslinked or non-crosslinked copolymer of maleic anhydride and an alkyl vinyl ether, the improvement which comprises carrying out said polymerization in a cosolvent system which comprises about 45 to 65% by weight cyclohexane and about 35 to 55% weight ethyl acetate.
Claim 2
Dependent Claim
48 words
In a polymerization process for making a crosslinked or non-crosslinked copolymer of maleic anhydride and an alkyl vinyl ether, the improvement which comprises carrying out said polymerization in a cosolvent system which comprises about 45 to 65% by weight cyclohexane and about 35 to 55% weight ethyl acetate.
Claim 3
Dependent Claim
20 words
A process according to claim 1, wherein a crosslinked copolymer is obtained and said crosslinking agent is a diethylenic compound.
Claim 4
Dependent Claim
44 words
A process according to claim 2, wherein said crosslinking agent is selected from 1,7-octadiene, 1,9-decadiene, divinylbenzene, 1,4-butanediol divinyl ether, bis-methylene acrylamide, 1,4-divinyloxybutane, a divinyl ether of an aliphatic diol, polyethylene glycol diacrylate, trimethylolpropane triacrylate, propylene glycol diacrylate and polyhydric alcohols esterified with acrylic acid.
Claim 5
Dependent Claim
24 words
A process according to claim 1, wherein the mole ratio of maleic anhydride and alkyl vinyl ether is about 1:1.05 to about 1:2, respectively.
Claim 6
Dependent Claim
40 words
A process according to claim 2, wherein the resulting crosslinked copolymer is obtained as a fine white powder in pumpable slurry form in the cosolvent system, and is characterized by being of high viscosity, good stability, and excellent salt tolerance.
Claim 7
Dependent Claim
12 words
A process according to claim 1, wherein said copolymer is not crosslinked.
References Cited (Backward Citations)
GB328725A
Cited
DE3233775A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-07-22 | 1995-01-21 | 1995-07-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-07-22 | 1999-01-21 | 1999-07-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-07-22 | 2003-01-21 | 2003-07-23 | $7700.00 | Window Closed / Lapsed |