US3014897A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Stereospecific polymer and method of preparing
Assignee: Wyeth Holdings LLC
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Filing: 1958-04-30
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Granted: 1961-12-26
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Expires: 1978-04-30
Abstract
No abstract record available.
Inventors
- 👤 Hodes William
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 06:18
CPC Classifications
C; C08; C08F; C08F32/00
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
178 words
A METHOD OF MAKING A CRYSTALLINE POLYMER OF METHYLSTYRENES, SAID POLYMER HAVING A DENSITY BETWEEN 1.020 AND 1.080, A MELTING POINT BETWEEN 150* C. AND 215* C., D-SPACINGS OF 12.1, 6.28, 5.05 AND 4.44 AND AN INTRINSIC VISCOSITY OF ABOUT 4.1 WHICH COMPRISES REACTING, IN SOLUTION, AT A TEMPERATURE OF FROM ABOUT -10* C. TO ABOUT 120* C. AND UNDER AN INERT ATMOSPHERE, A MONOMER MIXTURE OF METHYLSTYRENES COMPRISING FROM ABOUT 10 TO 40 WEIGHT PERCENT ORTHO ISOMER, FROM 60 TO 90 WEIGHT PERCENT PARA ISOMER, AND MINOR AMOUNTS BUT NOT MORE THAN 5 WEIGHT PERCENT META ISOMER, THE TOTAL PERCENT OF THE ISOMERS IN SAID MONOMER MIXTURE BEING 100%, IN ADMIXTURE WITH A CATALYST SYSTEM COMPRISING A MIXTURE OF (1) FROM ABOUT 0.1% TO ABOUT 10% OF TITANIUM TRICHLORIDE AND (2) FROM ABOUT 0.01% TO ABOUT 5% OF TRIETHYL ALUMINUM, SAID PERCENTAGES OF CATALYST BEING BASED ON THE TOTAL WEIGHT OF THE METHYLSTYRENE, AND ANNEALING UNDER HEAT AND IN AN INERT ATMOSPHERE THE FRACTION OF THE POLYMERIC PRODUCT WHICH IS INSOLUBLE IN ACETONE AND METHYL ETHYL KETONE.
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) | 1964-12-25 | 1965-06-26 | 1965-12-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-12-25 | 1969-06-26 | 1969-12-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-12-25 | 1973-06-26 | 1973-12-26 | $7700.00 | Window Closed / Lapsed |