Patent US3687908A successfully refreshed from Google Patents.
US3687908A
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Polymers containing nitrile and thioamide groups and their preparation
Assignee: United States Department of the Air Force
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Filing: 1971-02-02
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Granted: 1972-08-29
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Expires: 1991-02-02
Abstract
Abstract Novel polymers containing nitrile and thioamide groups are prepared by contacting a polymer of acrylonitrile or vinylidene cyanide with hydrogen sulfide at a temperature below about 50* C in the presence of a catalytic amount of an alkali metal carbonate. The polymers are useful as coatings and in the preparation of fibers and films.
Inventors
- 👤 Lewellyn G Picklesimer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 06:47
CPC Classifications
C; C08; C08F; C08F8/00; C08F8/34; C08F2800/00; C08F2800/20
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
14 words
The polymer according to claim 1 in which R1 is and R2 is hydrogen.
Claim 2
Dependent Claim
17 words
The polymer according to claim 2 in which 20 to 80 percent of said R1 groups are
Claim 3
Dependent Claim
19 words
The polymer according to claim 1 which consisting essentially of a plurality of repeating units having the following formulas:
Claim 4
Dependent Claim
25 words
The polymer according to claim 1 in which R1 and R2 are from about 20 to 80 percent of the R1 and R2 groups being
Claim 5
Dependent Claim
100 words
A process for preparing a polymer having nitrile and thioamide groups which comprises the steps of contacting with hydrogen sulfide gas a polymer having nitrile groups selected from the group consisting of polymers of acrylonitrile and polymers of vinylidene cyanide, said polymers being in solution in a solvent selected from the group consisting of dimethylformamide, dimethylacetamide and dimethylsulfoxide and said contacting occurring in the presence of a catalytic amount of an alkali metal carbonate at a temperature below about 50* C.; and continuing said contacting until about 20 to 80 percent of the nitrile groups are converted to thioamide groups.
Claim 6
Dependent Claim
15 words
The process according to claim 6 in which said polymer is a polymer of acrylonitrile.
Claim 7
Dependent Claim
17 words
The process according to claim 6 in which said polymer is a copolymer of acrylonitrIle and methylmethacrylate.
Claim 8
Dependent Claim
16 words
The process according to claim 6 in which said polymer is a polymer of vinylidene cyanide.
Claim 9
Dependent Claim
55 words
The process according to claim 6 in which said polymer is dissolved in said solvent, said catalyst is added to the resulting solution, said hydrogen sulfide is bubbled through said solution for a period of from about one half to 10 hours, and said polymer having nitrile and thioamide groups is recovered from said solution.
Claim 10
Dependent Claim
27 words
The process according to claim 10 in which said polymer having nitrile and thioamide groups is recovered by contacting said solution with water, thereby precipitating said polymer.
Claim 11
Dependent Claim
32 words
The process according to claim 6 in which said catalyst is sodium, potassium or lithium carbonate and the amount of catalyst used is about 1 to 10 weight percent of said polymer.
References Cited (Backward Citations)
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Cited
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US2563662A
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US2891932A
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US2893908A
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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) | 1975-08-29 | 1976-02-28 | 1976-08-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-29 | 1980-02-28 | 1980-08-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-29 | 1984-02-28 | 1984-08-29 | $7700.00 | Window Closed / Lapsed |