Patent US3922295A successfully refreshed from Google Patents.
US3922295A
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US
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Isocyanate-containing oligomeric polyanhydrides
Assignee: Pharmacia and Upjohn Co
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Filing: 1974-09-25
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Granted: 1975-11-25
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Expires: 1994-09-25
Abstract
Abstract Novel oligomeric poly N-carboxylic anhydrides having the following structure are disclosed. The unit Ar represents arylene and x represents an integer from 1 to 10 and y represents a number having an average value from 0 to 4. The polyanhydrides serve as useful storage stable intermediates for the production of polyamides to which they are easily converted by the elimination of carbon dioxide. A process for the preparation of the polyanhydrides from arylene diisocyanates and Alpha , omega -alkylene dicarboxylic acids is disclosed. Processes for the conversion of the polyanhydrides to the corresponding polyamides are also disclosed.
Inventors
- 👤 James N Tilley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:56
CPC Classifications
C; C07; C07C; C07C265/00; C07C265/12; C08; C08G; C08G18/00; C08G18/06; C08G18/28; C08G18/30; C08G18/34; C08G18/341; C08G69/00; Y; Y10; Y10S; Y10S528/00; Y10S528/903
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
8 words
AN OLIGOMERIC POLY N-CARBOXYLIC ANHYDRIDE HAVING THE STRUCTURE
Claim 2
Dependent Claim
8 words
AN OLIGOMERIC POLY N-CARBOXYLIC ANHYDRIDE HAVING THE STRUCTURE
Claim 3
Dependent Claim
11 words
A poly N-carboxylic anhydride according to claim 1 wherein Ar represents
Claim 4
Dependent Claim
16 words
A poly N-carboxylic anhydride according to claim 1 wherein 80 percent of said arylene radicals are
Claim 5
Dependent Claim
14 words
A poly N-carboxylic anhydride according to claim 1 wherein x is equal to 7.
Claim 6
Dependent Claim
14 words
A poly N-carboxylic anhydride according to claim 1 wherein y is equal to 3.
Claim 7
Dependent Claim
46 words
A process for the preparation of an oligomeric poly N-carboxylic anhydride according to claim 1 said process comprising reacting under anhydrous conditions an arylene diisocyanate selected from the group consisting of phenylene diisocyanate, tolylene diisocyanate, xylylene diisocyanate, naphthylene diisocyanate, diphenylylene diisocyanate, and diisocyanates having the formula
Claim 8
Dependent Claim
11 words
A process according to claim 6 wherein said diisocyanate is 4,4''-methylenebis(phenylisocyanate).
Claim 9
Dependent Claim
24 words
A process according to claim 6 wherein said diisocyanate comprises a mixture of 80 mole percent 4,4''-methylenebis(phenylisocyanate) and 20 mole percent of 2,4-toluene diisocyanate.
Claim 10
Dependent Claim
13 words
A process according to claim 6 wherein said dicarboxylic acid is azelaic acid.
Claim 11
Dependent Claim
31 words
A process according to claim 6 wherein said diisocyanate and said dicarboxylic acid are brought together in the absence of solvent at a temperature of from about 80*C to about 150*C.
Claim 12
Dependent Claim
33 words
A process according to claim 6 wherein said diisocyanate and said dicarboxylic acid are brought together in the presence of a polar solvent at a temperature of from about -60*C to about 50*C.
Claim 13
Dependent Claim
11 words
A process according to claim 11 wherein said solvent is tetrahydrofuran.
Claim 14
Dependent Claim
11 words
A process according to claim 11 wherein said solvent is N-methylpyrrolidone.
References Cited (Backward Citations)
US2268586A
Cited
US3642715A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-11-24 | 1979-05-26 | 1979-11-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-24 | 1983-05-26 | 1983-11-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-24 | 1987-05-26 | 1987-11-25 | $7700.00 | Window Closed / Lapsed |