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US3386932A
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US
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Novel cellulosics, segmented copolymers, and methods of preparing same
Assignee: Celanese Corp
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Filing: 1965-12-22
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Granted: 1968-06-04
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Expires: 1985-12-22
Abstract
No abstract record available.
Inventors
- 👤 Henry W Steinmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:01
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/28; C08G18/40; C08G18/64; C08G18/6484; C08B; C08B15/00; C08B3/00; C08B3/22; C08G18/08; C08G18/10
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
80 words
A PROCESS FOR PREPARING COPOLYMERS WHICH COMPRISES DEPOLYMERIZING A HIGH MOLECULAR WEIGHT POLYANHYDROGLUCOSE TRIESTER WHILE MAINTAINING THE ESTER GROUPS THEREOF SUBSTANTIALLY INTACT TO FORM A LOW MOLECULAR WEIGHT POLYANHYDROGLUCOSE TRIESTER BY CONTACTING SAID HIGH MOLECULAR WEIGHT TRIESTER IN A SOLVENT THEREFOR WITH AN ACID CATALYST, RECOVERING THE LOW MOLECULAR WEIGHT TRIESTER, REACTING THE LOW MOLECULAR WEIGHT TRIESTER WITH AN ORGANIC DIISOCYANATE AND A POLYMER HAVING TERMINAL FUNCTIONAL GROUPS POSSESSING ACTIVE HYDROGEN, AND RECOVERING COPOLYMERS OF LOW MOLECULAR WEIGHT POLYANHYDROGLUCOSE TRIESTER.
Claim 2
Dependent Claim
80 words
A PROCESS FOR PREPARING COPOLYMERS WHICH COMPRISES DEPOLYMERIZING A HIGH MOLECULAR WEIGHT POLYANHYDROGLUCOSE TRIESTER WHILE MAINTAINING THE ESTER GROUPS THEREOF SUBSTANTIALLY INTACT TO FORM A LOW MOLECULAR WEIGHT POLYANHYDROGLUCOSE TRIESTER BY CONTACTING SAID HIGH MOLECULAR WEIGHT TRIESTER IN A SOLVENT THEREFOR WITH AN ACID CATALYST, RECOVERING THE LOW MOLECULAR WEIGHT TRIESTER, REACTING THE LOW MOLECULAR WEIGHT TRIESTER WITH AN ORGANIC DIISOCYANATE AND A POLYMER HAVING TERMINAL FUNCTIONAL GROUPS POSSESSING ACTIVE HYDROGEN, AND RECOVERING COPOLYMERS OF LOW MOLECULAR WEIGHT POLYANHYDROGLUCOSE TRIESTER.
Claim 3
Dependent Claim
52 words
THE PROCESS OF CLAIM 1 WHEREIN SAID POLYMER HAVING TERMINAL FUNCTIONAL GROUPS POSSESSING ACTIVE HYDROGEN IS SELECTED FROM THE GROUP CONSISTING OF LOW MOLECULAR WEIGHT POLYESTERS AND LOW MOLECULAR WEIGHT POLYETHERS, SAID POLYESTERS AND POLYETHERS HAVING AN AVERAGE MOLECULAR WEIGHT OF FROM ABOUT 250 TO ABOUT 5000 AND MELTING BELOW ABOUT 60*C.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1971-06-04 | 1971-12-04 | 1972-06-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-06-04 | 1975-12-04 | 1976-06-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-06-04 | 1979-12-04 | 1980-06-04 | $7700.00 | Window Closed / Lapsed |