US4100079A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polymers for acid thickening
Assignee: ECC SPECIALTY CHEMICALS Inc
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Filing: 1977-02-25
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Granted: 1978-07-11
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Expires: 1997-02-25
Abstract
Abstract Acids, particularly dilute acid solutions thickened with copolymers of dimethyl diallyl ammonium chloride and a monomer capable of postreaction after polymerization to provide branching or partial crosslinking, are useful as oil well drilling and fracturing fluids for stimulating well production.
Inventors
- 👤 Gloria DiMarco Sinkovitz
- 👤 Andrew Jackson Sharpe, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 09:48
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/60; C09K8/62; C09K8/72; C09K8/74; C09K8/84; C09K8/86; C09K8/88; C09K8/882; Y; Y10; Y10S; Y10S507/00; Y10S507/922; Y10S507/923
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
135 words
A method of fracturing a subterranean formation comprising: a. contacting said formation with an aqueous fracturing fluid which contains an acid which is capable of reacting with subterranean carbonate formations and as a thickening agent therefore at least 0.5 percent by weight of the acid and water of a copolymer having a molecular weight of at least 5,000, said copolymer containing from about 50 to about 98 weight percent dimethyl diallyl ammonium chloride and from about 2 to about 50 weight percent of a monomer capable of postreaction after polymerization to provide branching or partial crosslinking said monomer being selected from the group consisting of N-methylolacrylamide and diacetone acrylamide; b. applying sufficient pressure to the said fracturing fluid to fracture said formation; and c. maintaining said pressure while forcing said fracturing fluid into said fracture.
Claim 2
Independent Claim
135 words
A method of fracturing a subterranean formation comprising: a. contacting said formation with an aqueous fracturing fluid which contains an acid which is capable of reacting with subterranean carbonate formations and as a thickening agent therefore at least 0.5 percent by weight of the acid and water of a copolymer having a molecular weight of at least 5,000, said copolymer containing from about 50 to about 98 weight percent dimethyl diallyl ammonium chloride and from about 2 to about 50 weight percent of a monomer capable of postreaction after polymerization to provide branching or partial crosslinking said monomer being selected from the group consisting of N-methylolacrylamide and diacetone acrylamide; b. applying sufficient pressure to the said fracturing fluid to fracture said formation; and c. maintaining said pressure while forcing said fracturing fluid into said fracture.
Claim 3
Dependent Claim
21 words
The method of claim 1 wherein the monomer capable of postreaction after polymerization to provide branching or partial crosslinking is N-methylolacrylamide.
Claim 4
Dependent Claim
106 words
A fracturing fluid composition for use in fracturing subterranean formations comprising: (a) water; (b) acid which is capable of reacting with subterranean carbonate formations; and (c) at least 0.5 percent by weight of the acid and water of a thickening agent composition consisting essentially of a copolymer having a molecular weight of at least 5,000, said copolymer containing from about 50 to about 98 weight percent dimethyl diallyl ammonium chloride and from about 2 to about 50 weight percent of a monomer capable of postreaction after polymerization to provide branching or partial crosslinking said monomer being selected from the group consisting of N-methylolacrylamide and diacetone acrylamide.
Claim 5
Dependent Claim
106 words
A fracturing fluid composition for use in fracturing subterranean formations comprising: (a) water; (b) acid which is capable of reacting with subterranean carbonate formations; and (c) at least 0.5 percent by weight of the acid and water of a thickening agent composition consisting essentially of a copolymer having a molecular weight of at least 5,000, said copolymer containing from about 50 to about 98 weight percent dimethyl diallyl ammonium chloride and from about 2 to about 50 weight percent of a monomer capable of postreaction after polymerization to provide branching or partial crosslinking said monomer being selected from the group consisting of N-methylolacrylamide and diacetone acrylamide.
Claim 6
Dependent Claim
11 words
The composition of claim 3 wherein the acid is hydrochloric acid.
Claim 7
Dependent Claim
21 words
The composition of claim 3 wherein the monomer capable of postreaction after polymerization to provide branching or partial crosslinking is N-methylolacrylamide.
Claim 8
Independent Claim
104 words
A method of thickening a mixture of water and one acid which is capable of reacting with subterranean carbonate formations which comprises adding thereto at least 0.5 percent by weight of the acid and water of a thickening agent composition consisting essentially of a copolymer having a molecular weight of at least 5,000, said copolymer containing from about 50 to about 98 weight percent dimethyl diallyl ammonium chloride and from about 2 to about 50 weight percent of a monomer capable of postreaction after polymerization to provide branching or partial crosslinking said monomer being selected from the group consisting of N-methylolacrylamide and diacetone acrylamide.
Claim 9
Independent Claim
104 words
A method of thickening a mixture of water and one acid which is capable of reacting with subterranean carbonate formations which comprises adding thereto at least 0.5 percent by weight of the acid and water of a thickening agent composition consisting essentially of a copolymer having a molecular weight of at least 5,000, said copolymer containing from about 50 to about 98 weight percent dimethyl diallyl ammonium chloride and from about 2 to about 50 weight percent of a monomer capable of postreaction after polymerization to provide branching or partial crosslinking said monomer being selected from the group consisting of N-methylolacrylamide and diacetone acrylamide.
Claim 10
Dependent Claim
22 words
A method as in claim 6 wherein the monomer capable of postreaction after polymerization to provide branching or partial crosslinking is N-methylolacrylamide.
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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) | 1981-07-10 | 1982-01-09 | 1982-07-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-07-10 | 1986-01-09 | 1986-07-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-07-10 | 1990-01-09 | 1990-07-11 | $7700.00 | Window Closed / Lapsed |