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US3994852A
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US
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Low fluid loss cementing compositions containing polyvinylpyrrolidone-polyacrylamide triblock polymers and their use
Assignee: Calgon Corp
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Filing: 1975-07-17
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Granted: 1976-11-30
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Expires: 1995-07-17
Abstract
Abstract Improved cementing compositions and their use in well cementing operations is disclosed, wherein polyvinylpyrrolidone-polyacrylamide triblock polymers are used as fluid loss additives for aqueous hydraulic cement slurries.
Inventors
- 👤 Sally Lee Adams
- 👤 Lawrence James Guilbault
- 👤 Fred David Martin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 10:00
CPC Classifications
C; C04; C04B; C04B24/00; C04B24/24; C04B24/26; C04B24/2652; C04B28/00; C04B28/02; C08; C08K; C08K3/00; C08K3/01; C08K3/013; C09; C09K; C09K8/00; C09K8/42; C09K8/46; C09K8/467; C09K8/487
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
73 words
A low fluid loss cement composition capable of forming a fluid slurry when mixed with water, said cement composition comprising dry hydraulic cement and from about 0.05 to about 5.0 percent by weight, based on dry hydraulic cement, of a water-soluble triblock copolymer of the formula A-B-A wherein the A block represents from 10 to 100,000 mer units of acrylamide and the B block represents from 10 to 5,000 mer units of N-vinyl-2-pyrrolidone.
Claim 2
Dependent Claim
73 words
A low fluid loss cement composition capable of forming a fluid slurry when mixed with water, said cement composition comprising dry hydraulic cement and from about 0.05 to about 5.0 percent by weight, based on dry hydraulic cement, of a water-soluble triblock copolymer of the formula A-B-A wherein the A block represents from 10 to 100,000 mer units of acrylamide and the B block represents from 10 to 5,000 mer units of N-vinyl-2-pyrrolidone.
Claim 3
Dependent Claim
38 words
The cement composition of claim 1 wherein the A block constitutes from about 50 to about 98 mole percent of the copolymer and the B block constitutes from about 50 to about 2 mole percent of the copolymer.
Claim 4
Dependent Claim
16 words
The cement composition of claim 1 wherein the molecular weight of the N-vinyl-2-pyrrolidone is about 360,000.
Claim 5
Dependent Claim
66 words
A hydraulic cement slurry composition comprising dry hydraulic cement; from about 0.05 to about 5.0 percent by weight, based on dry hydraulic cement, of a water-soluble triblock copolymer of the formula A-B-A wherein the A block represents from 10 to 100,000 mer units of acrylamide and the B block represents from 10 to 5,000 mer units of N-vinyl-2-pyrrolidone; and sufficient water to form a pumpable slurry.
Claim 6
Dependent Claim
66 words
A hydraulic cement slurry composition comprising dry hydraulic cement; from about 0.05 to about 5.0 percent by weight, based on dry hydraulic cement, of a water-soluble triblock copolymer of the formula A-B-A wherein the A block represents from 10 to 100,000 mer units of acrylamide and the B block represents from 10 to 5,000 mer units of N-vinyl-2-pyrrolidone; and sufficient water to form a pumpable slurry.
Claim 7
Dependent Claim
38 words
The cement composition of claim 4 wherein the A block constitutes from about 50 to about 98 mole percent of the copolymer and the B block constitutes from about 50 to about 2 mole percent of the copolymer.
Claim 8
Dependent Claim
16 words
The cement composition of claim 4 wherein the molecular weight of the N-vinyl-2-pyrrolidone is about 360,000.
Claim 9
Independent Claim
72 words
A method of producing a hydraulic cement aqueous slurry composition comprising admixing together hydraulic cement, from about 0.05 to about 5.0 percent by weight, based on dry hydraulic cement, of a water-soluble triblock copolymer of the formula A-B-A wherein the A block represents from 10 to 100,000 mer units of acrylamide and the B block represents from 10 to 5,000 mer unis of N-vinyl-2-pyrrolidone, and sufficient water to form a pumpable slurry.
Claim 10
Independent Claim
72 words
A method of producing a hydraulic cement aqueous slurry composition comprising admixing together hydraulic cement, from about 0.05 to about 5.0 percent by weight, based on dry hydraulic cement, of a water-soluble triblock copolymer of the formula A-B-A wherein the A block represents from 10 to 100,000 mer units of acrylamide and the B block represents from 10 to 5,000 mer unis of N-vinyl-2-pyrrolidone, and sufficient water to form a pumpable slurry.
Claim 11
Dependent Claim
37 words
The method of claim 7 wherein the A block constitutes from about 50 to about 98 mole percent of the copolymer and the B block constitutes from about 50 to about 2 mole percent of the copolymer.
Claim 12
Dependent Claim
15 words
The method of claim 7 wherein the molecular weight of the N-vinyl-2-pyrrolidone is about 360,000.
Claim 13
Independent Claim
118 words
A method of cementing a zone in a well penetrating a subterranean formation comprising injecting down the well and positioning in the zone to be cemented a hydraulic cement aqueous slurry composition comprising dry hydraulic cement, from about 0.05 to about 5.0 percent by weight, based on dry hydraulic cement, of a water-soluble triblock copolymer of the formula A-B-A wherein the A block represents from 10 to 100,000 mer units of acrylamide and the B block represents from 10 to 5,000 mer units of N-vinyl-2-pyrrolidone, and sufficient water to form a pumpable slurry; and allowing the cement thus positioned to set to a monolithic mass; whereby loss of fluid from the cement slurry to the formation is reduced.
Claim 14
Independent Claim
118 words
A method of cementing a zone in a well penetrating a subterranean formation comprising injecting down the well and positioning in the zone to be cemented a hydraulic cement aqueous slurry composition comprising dry hydraulic cement, from about 0.05 to about 5.0 percent by weight, based on dry hydraulic cement, of a water-soluble triblock copolymer of the formula A-B-A wherein the A block represents from 10 to 100,000 mer units of acrylamide and the B block represents from 10 to 5,000 mer units of N-vinyl-2-pyrrolidone, and sufficient water to form a pumpable slurry; and allowing the cement thus positioned to set to a monolithic mass; whereby loss of fluid from the cement slurry to the formation is reduced.
Claim 15
Dependent Claim
37 words
The method of claim 10 wherein the A block constitutes from about 50 to about 98 mole percent of the copolymer and the B block constitutes from about 50 to about 2 mole percent of the copolymer.
Claim 16
Dependent Claim
15 words
The method of claim 10 wherein the molecular weight of the N-vinyl-2-pyrrolidone is about 360,000.
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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) | 1979-11-30 | 1980-05-31 | 1980-11-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-11-30 | 1984-05-31 | 1984-11-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-11-30 | 1988-05-31 | 1988-11-30 | $7700.00 | Window Closed / Lapsed |