Patent US3849515A successfully refreshed from Google Patents.
US3849515A
Expired / Lapsed
US
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Process for the preparation of polyether/polyester block copolymers
Assignee: Bayer AG
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Filing: 1973-02-23
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Granted: 1974-11-19
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Expires: 1993-02-23
Abstract
Abstract 1. A PROCESS FOR THE PREPARATION OF POLYETHER/POLYESTER BLOCK COPOLYMERS WHICH COMPRISES CONDENSING, IN THE PRESENCE OF AN ETHERIFICATION CATALYST AT A TEMPERATURE 130*C.-220*C., HYDROXYL SATURATED POLYESTERS AND HYDROXYL POLYESTERS EACH CONTAINING FREE HYDROXYL GROUPS, SAID POLYESTER HAS A MOLECULAR WEIGHT OF 250-3000 AND SAID POLYETHER HAS A MOLECULAR WEIGHT OF 500-3000, THE MOLAR RATIO OF POLYESTER TO POLYETHER BEING FROM ABOUT 5:1 TO ABOUT 1:5.
Inventors
- 👤 E Muller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 11:24
CPC Classifications
C; C08; C08G; C08G81/00; C08G18/00; C08G18/06; C08G18/28; C08G18/40; C08G18/42; C08G18/4244; C08G63/00; C08G63/66; C08G63/668; C08G63/672; C08L; C08L67/00; C08L67/02
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
65 words
A PROCESS FOR THE PREPARATION OF POLYETHER/POLYESTER BLOCK COPOLYMERS WHICH COMPRISES CONDENSING, IN THE PRESENCE OF AN ETHERIFICATION CATALYST AT A TEMPERATURE 130*C.-220*C., HYDROXYL SATURATED POLYESTERS AND HYDROXYL POLYESTERS EACH CONTAINING FREE HYDROXYL GROUPS, SAID POLYESTER HAS A MOLECULAR WEIGHT OF 250-3000 AND SAID POLYETHER HAS A MOLECULAR WEIGHT OF 500-3000, THE MOLAR RATIO OF POLYESTER TO POLYETHER BEING FROM ABOUT 5:1 TO ABOUT 1:5.
Claim 2
Dependent Claim
65 words
A PROCESS FOR THE PREPARATION OF POLYETHER/POLYESTER BLOCK COPOLYMERS WHICH COMPRISES CONDENSING, IN THE PRESENCE OF AN ETHERIFICATION CATALYST AT A TEMPERATURE 130*C.-220*C., HYDROXYL SATURATED POLYESTERS AND HYDROXYL POLYESTERS EACH CONTAINING FREE HYDROXYL GROUPS, SAID POLYESTER HAS A MOLECULAR WEIGHT OF 250-3000 AND SAID POLYETHER HAS A MOLECULAR WEIGHT OF 500-3000, THE MOLAR RATIO OF POLYESTER TO POLYETHER BEING FROM ABOUT 5:1 TO ABOUT 1:5.
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) | 1977-11-18 | 1978-05-20 | 1978-11-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-11-18 | 1982-05-20 | 1982-11-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-11-18 | 1986-05-20 | 1986-11-19 | $7700.00 | Window Closed / Lapsed |