US4263444A
Expired / Lapsed
US
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Hydroxy terminated polybutadiene based polyurethane bound propellant grains
Assignee: ATK Launch Systems LLC
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Filing: 1978-11-17
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Granted: 1981-04-21
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Expires: 1998-11-17
Abstract
Abstract Salicylate esters have been found to be suitable blocking agents for polyisocyanates, enabling preparation of hydroxy terminated polybutadiene based polyurethane bound propellant grains having extended pot life. Unblocking occurs readily at normal propellant cure temperatures, allowing normal cure rates.
Inventors
- 👤 William H. Graham
- 👤 Inella G. Shepard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 04:20
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/70; C08G18/72; C08G18/80; C08G18/8061; C08G18/8064; C08G18/8067; C06; C06B; C06B45/00; C06B45/04; C06B45/06; C06B45/10; C08G18/28; C08G18/67; C08G18/69
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
67 words
A curable composition comprising a liquid hydroxy terminated polybutadiene and a compound of the formula: ##STR3## wherein X is an n valent organic radical; R is hydrogen or lower alkyl of about 1 to about 10 carbon atoms; R' is lower alkyl of about 1 to about 10 carbon atoms, or carbocyclic aryl of from 6 to about 10 carbon atoms; and n is 2 or 3.
Claim 2
Dependent Claim
67 words
A curable composition comprising a liquid hydroxy terminated polybutadiene and a compound of the formula: ##STR3## wherein X is an n valent organic radical; R is hydrogen or lower alkyl of about 1 to about 10 carbon atoms; R' is lower alkyl of about 1 to about 10 carbon atoms, or carbocyclic aryl of from 6 to about 10 carbon atoms; and n is 2 or 3.
Claim 3
Dependent Claim
24 words
A compound as defined in claim 1 wherein R is H; R' is n-octyl; n is 2 and X is a methyl phenylene diradical.
References Cited (Backward Citations)
US4098626A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-04-20 | 1984-10-20 | 1985-04-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-04-20 | 1988-10-20 | 1989-04-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-04-20 | 1992-10-20 | 1993-04-21 | $7700.00 | Window Closed / Lapsed |