US4090992A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dispersions of water soluble polymers in oil
Assignee: Drew Chemical Corp
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Filing: 1977-08-18
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Granted: 1978-05-23
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Expires: 1997-08-18
Abstract
Abstract Water soluble polymers dispersed in a water-in-oil emulsion are treated to reduce the water content thereof to provide a polymer dispersed in oil which is stable to coagulation or agglomeration during subsequent treatment. The composition can be chemically modified and/or made self dissolving in water by addition of surfactant without polymer agglomeration.
Inventors
- 👤 Clyde S. Scanley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 10:44
CPC Classifications
C; C08; C08J; C08J3/00; C08J3/02; C08J3/09; C08F; C08F8/00; C08G; C08G73/00; C08G73/02; C08G73/0206; D; D06; D06M; D06M15/00; D06M15/19; D06M15/21; D06M15/285; D21; D21H; D21H17/00; D21H17/20; D21H17/33; D21H17/34; D21H17/37; D21H17/41; D21H17/44; D21H17/45; D21H17/455; C08J2300/00; C08J2300/14
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
93 words
An improved process for chemically modifying a water soluble polymer selected from the group consisting of acrylamide polymers and methacrylamide polymers, comprising: chemically modifying said polymer dispersed in oil, without coagulation or agglomeration of said polymer, said dispersion having a water content at which the polymer remains finely divided and dispersed in the oil, said water content being less than 40%, by weight, based on said polymer and water, said polymer dispersed in oil having been prepared from a water in oil emulsion of said polymer by reduction of the water content thereof.
Claim 2
Dependent Claim
93 words
An improved process for chemically modifying a water soluble polymer selected from the group consisting of acrylamide polymers and methacrylamide polymers, comprising: chemically modifying said polymer dispersed in oil, without coagulation or agglomeration of said polymer, said dispersion having a water content at which the polymer remains finely divided and dispersed in the oil, said water content being less than 40%, by weight, based on said polymer and water, said polymer dispersed in oil having been prepared from a water in oil emulsion of said polymer by reduction of the water content thereof.
Claim 3
Dependent Claim
38 words
The process of claim 1 wherein said chemical modification is selected from the group consisting of hydrolysis of amide to carboxyl, dimethylaminomethylation of amide, sulfomethylation of amide, Hoffman reaction, and exchange of amide nitrogen for nitrogen of N,N-dimethylaminopropylamine.
Claim 4
Dependent Claim
14 words
The process of claim 1 wherein said chemical modification is hydrolysis with gaseous ammonia.
Claim 5
Dependent Claim
23 words
The process of claim 2 wherein said water content is from 1% to 30%, by weight, of water, based on polymer and water.
Claim 6
Dependent Claim
23 words
The process of claim 4 wherein said water content is from 1 to 15%, by weight, of water, based on polymer and water.
Claim 7
Dependent Claim
34 words
The process of claim 2 wherein the polymer dispersed in oil is prepared from a water in oil emulsion containing from about 50 to about 90%, by weight, water, based on polymer and water.
Claim 8
Dependent Claim
16 words
The process of claim 2 wherein the polymer has a molecular weight of at least 100,000.
Claim 9
Dependent Claim
15 words
The process of claim 2 wherein the chemical modification is hydrolysis of amide to carboxyl.
Claim 10
Dependent Claim
13 words
The process of claim 2 wherein the chemical modification is dimethylaminomethylation of amide.
Claim 11
Dependent Claim
13 words
The process of claim 2 wherein the chemical modification is sulfomethylation of amide.
Claim 12
Dependent Claim
12 words
The process of claim 2 wherein the chemical modification is Hoffman reaction.
Claim 13
Dependent Claim
18 words
The process of claim 2 wherein the chemical modification is exchange of amide nitrogen for nitrogen of N,N-dimethylaminopropylamine.
References Cited (Backward Citations)
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US3826771A
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US3849361A
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US3957739A
Cited
US3997492A
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US4021399A
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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) | 1981-05-22 | 1981-11-21 | 1982-05-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-05-22 | 1985-11-21 | 1986-05-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-05-22 | 1989-11-21 | 1990-05-23 | $7700.00 | Window Closed / Lapsed |