US3706713A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Aliphatic polycarbonates
Assignee: Shell USA Inc
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Filing: 1970-08-11
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Granted: 1972-12-19
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Expires: 1990-08-11
Abstract
Abstract Compositions comprising novel copolymers of carbon dioxide and one or more aliphatic 1,2 monoepoxide having at least four carbon atoms per molecule are prepared in the presence of a catalytic amount of a catalyst system comprising an organo metallic compound of magnesium, zinc or cadmium, an amine and water at pressures between 1 and 200 atmospheres and temperatures between 20* and 225* C. The compositions are useful for moldings, films and fibers.
Inventors
- 👤 Colin G Hull
- 👤 John Boor Jr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 18:57
CPC Classifications
C; C08; C08G; C08G64/00; C08G64/02; C08G64/0208; C08G64/20; C08G64/32; C08G64/34
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
14 words
A process according to claim 1 wherein the organo metallic compound is of zinc.
Claim 2
Dependent Claim
15 words
A process according to claim 1 wherein the pressure is between 1 and 200 atmospheres.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-12-19 | 1976-06-19 | 1976-12-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-12-19 | 1980-06-19 | 1980-12-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-12-19 | 1984-06-19 | 1984-12-19 | $7700.00 | Window Closed / Lapsed |