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US4687828A
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Water soluble graft copolymers of lignin-(2-propenamide)-(sodium 2,2-dimethyl-3-imino-4-oxohex-5-ene-1-sulfonate), methods of making the same and uses therefor
Assignee: Southern Methodist University
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Filing: 1985-08-30
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Granted: 1987-08-18
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Expires: 2005-08-30
Abstract
Abstract A water-soluble graft copolymer of lignin-(2-propenamide)-(sodium 2,2-dimethyl-3-imino-4-oxohex-5-ene-1-sulfonate) having a central lignin network and at least one grafted side chain, R, having randomly repeating units of the formula: ##STR1## such that the central lignin network has a molecular weight of about 1,000 to 100,000 and the total number of randomly repeating units in the grafted side chain or chains is in the range of 1,000 to 300,000, such that the total copolymer molecular weight is in the range of 40,000 to 30,000,000. The copolymers of the present invention are useful as thickeners for water and aqueous solutions and may be advantageously used in the recovery of oil from subterranean wells or in the preparation and use of drilling fluid compositions.
Inventors
- 👤 John J. Meister
- 👤 Damodar R. Patil
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 08:39
CPC Classifications
C; C08; C08H; C08H6/00; C08F; C08F289/00; C08L; C08L51/00; C09; C09K; C09K8/00; C09K8/02; C09K8/04; C09K8/14; C09K8/18; C09K8/20; C09K8/203; C09K8/58; C09K8/588; C09K8/60
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
112 words
A water-soluble graft copolymer of lignin-(2-propenamide)-(sodium 2,2-dimethyl-3-imino-4-oxohex-5-ene-1-sulfonate) having a central lignin network and at least one grafted side chain, R, having randomly repeating units of 2-propenamide, having the formula (I), in the amount of from about 1-99 molar %, and of sodium 2,2-dimethyl-3-imino-4-oxohex-5-ene-1-sulfonate having the formula (II), in the amount of from about 99-1 molar %: ##STR8## such that the central lignin network has a molecular weight of about 1,000 to 100,000 and the total number of randomly repeating units in the grafted side chain or chains is in the range of 1,000 to 300,000 units, such that the total graft copolymer molecular weight is in the range of 40,000 to 30,000,000.
Claim 2
Dependent Claim
112 words
A water-soluble graft copolymer of lignin-(2-propenamide)-(sodium 2,2-dimethyl-3-imino-4-oxohex-5-ene-1-sulfonate) having a central lignin network and at least one grafted side chain, R, having randomly repeating units of 2-propenamide, having the formula (I), in the amount of from about 1-99 molar %, and of sodium 2,2-dimethyl-3-imino-4-oxohex-5-ene-1-sulfonate having the formula (II), in the amount of from about 99-1 molar %: ##STR8## such that the central lignin network has a molecular weight of about 1,000 to 100,000 and the total number of randomly repeating units in the grafted side chain or chains is in the range of 1,000 to 300,000 units, such that the total graft copolymer molecular weight is in the range of 40,000 to 30,000,000.
Claim 3
Dependent Claim
30 words
The water-soluble graft copolymer according to claim 1, wherein the lignin used as the central network is an alkali lignin, a HCl lignin, a milled-wood lignin or a 1,4-dioxane lignin.
Claim 4
Dependent Claim
15 words
The water-soluble graft copolymer according to claim 2, wherein said lignin is an alkali lignin.
Claim 5
Dependent Claim
120 words
The water-soluble graft copolymer according to claim 3, wherein said graft copolymer has the following unit formula: ##STR9## wherein n is defined such that the central lignin network has a molecular weight of about 1,000 to 100,000; and wherein said grafted side chain, R, has randomly repeating units of 2-propenamide, having the formula (I), in the amount of from about 1-99 molar %, and of sodium 2,2-dimethyl-3-imino-4-oxohex-5-ene-1-sulfonate, having the formula (II), in the amount of from about 99-1 molar %: ##STR10## such that the total numbers of randomly repeating units in the grafted side chain or chains is in the range of 1,000 to 300,000, such that the total copolymer molecular weight is in the range of 40,000 to 30,000,000.
Claim 6
Dependent Claim
18 words
The water-soluble graft copolymer according to claim 1, wherein the molecular weight is determined by size exclusion chromatography.
Claim 7
Dependent Claim
45 words
The water-soluble graft copolymer according to claim 1, wherein said grafted side chain, R, has randomly repeating units of 2-propenamide in the amount of about 20 to 80 molar %, and of sodium 2,2-dimethyl-3-imino-4-oxohex-5-ene-1-sulfonate, in the amount of from about 80 to 20 molar %.
References Cited (Backward Citations)
US3388061A
Cited
US3912706A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-08-17 | 1991-02-16 | 1991-08-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-08-17 | 1995-02-16 | 1995-08-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-08-17 | 1999-02-16 | 1999-08-18 | $7700.00 | Window Closed / Lapsed |