US3356646A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Preparation of high molecular weight thermoplastic polyhydroxyethers
Assignee: Union Carbide Corp
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Filing: 1965-07-14
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Granted: 1967-12-05
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Expires: 1985-07-14
Abstract
No abstract record available.
Inventors
- 👤 Wynstra John
- 👤 Herbert G Stine
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 18:16
CPC Classifications
C; C08; C08G; C08G59/00; C08G59/02; C08G59/04; C08G59/06
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
125 words
METHOD FOR THE PREPARATION OF THERMOPLASTIC POLYHYDROXYETHERS WHICH COMPRISES: (1) INTERACTING A DIHYDRIC POLYNUCLEAR PHENOL IN WHICH THE HYDROXYL GROUPS ARE ATTACHED TO DIFFERENT MUCLEI WITH A SUBSTANTIALLY EQUIMOLAR AMOUNT OF AN EPIHALOHYDRIN PER MOLE OF SAID PHENOL AND AN EXCESS OVER STOICHIOMETRIC PROPORTIONS OF AN ALKALI METAL HYDROXIDE IN AQUEOUS SOLUTION AT THE REFLUX TEMPERATURE OF THE MIXTURE UNTIL A PREPOLYMER IS FORMED; (2) HEATING THE REACTION MIXTURE TO ABOUT 150-200* C. UNTIL A POLYHYDROXYETHER HAVING A REDUCED VISCOSITYOF AT LEAST 0.45, MEASURED AT 25*C. AS A 0.2 GRAM SAMPLE IN 100 ML. OF TETRAHYDROFURAN, AND A WEIGHT AVERAGE MOLECULAR WEIGHT OF AT LEAST ABOUT 30,000 IS OBTAINED; (3) WASHING SAID POLYHYDROXYETHER WITH WATER; AND (4) RECOVERING SAID POLYHYDROXYETHER SUBSTANTIALLY FREE OF 1,2-EPOXY GROUPS.
Claim 2
Dependent Claim
125 words
METHOD FOR THE PREPARATION OF THERMOPLASTIC POLYHYDROXYETHERS WHICH COMPRISES: (1) INTERACTING A DIHYDRIC POLYNUCLEAR PHENOL IN WHICH THE HYDROXYL GROUPS ARE ATTACHED TO DIFFERENT MUCLEI WITH A SUBSTANTIALLY EQUIMOLAR AMOUNT OF AN EPIHALOHYDRIN PER MOLE OF SAID PHENOL AND AN EXCESS OVER STOICHIOMETRIC PROPORTIONS OF AN ALKALI METAL HYDROXIDE IN AQUEOUS SOLUTION AT THE REFLUX TEMPERATURE OF THE MIXTURE UNTIL A PREPOLYMER IS FORMED; (2) HEATING THE REACTION MIXTURE TO ABOUT 150-200* C. UNTIL A POLYHYDROXYETHER HAVING A REDUCED VISCOSITYOF AT LEAST 0.45, MEASURED AT 25*C. AS A 0.2 GRAM SAMPLE IN 100 ML. OF TETRAHYDROFURAN, AND A WEIGHT AVERAGE MOLECULAR WEIGHT OF AT LEAST ABOUT 30,000 IS OBTAINED; (3) WASHING SAID POLYHYDROXYETHER WITH WATER; AND (4) RECOVERING SAID POLYHYDROXYETHER SUBSTANTIALLY FREE OF 1,2-EPOXY GROUPS.
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) | 1970-12-04 | 1971-06-05 | 1971-12-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-12-04 | 1975-06-05 | 1975-12-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-12-04 | 1979-06-05 | 1979-12-05 | $7700.00 | Window Closed / Lapsed |