Patent US4127513A successfully refreshed from Google Patents.
US4127513A
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Method for preparing polyether glycols
Assignee: EIDP Inc
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Filing: 1977-11-09
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Granted: 1978-11-28
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Expires: 1997-11-09
Abstract
Abstract The production of undesirable oligomeric cyclic ethers in the preparation of polyether glycols is reduced by using as a catalyst an acid-activated montmorillonite clay which contains, per gram, 0.1 to 0.9 milliequivalent of hydrogen ions having pK a values of -3 to -8.
Inventors
- 👤 Harold E. Bellis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 18:30
CPC Classifications
C; C08; C08G; C08G65/00; C08G65/02; C08G65/26; C08G65/2642; C08G65/2645; C08G65/2654; C08G65/2657; C08G18/00; C08G18/06; C08G18/28; C08G18/40; C08G18/48; C08G18/4854; C08G65/04; C08G65/06; C08G65/16; C08G65/20
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
59 words
In a process for preparing a polyether glycol by the copolymerization of tetrahydrofuran and an alkylene oxide of 2 to 6 carbon atoms, in which an acid-activated montmorillonite clay is used as a catalyst, the improvement of using a clay which contains, per gram, 0.1 to 0.9 milliequivalent of hydrogen ions having pK a values of -3 to -8.
Claim 2
Dependent Claim
59 words
In a process for preparing a polyether glycol by the copolymerization of tetrahydrofuran and an alkylene oxide of 2 to 6 carbon atoms, in which an acid-activated montmorillonite clay is used as a catalyst, the improvement of using a clay which contains, per gram, 0.1 to 0.9 milliequivalent of hydrogen ions having pK a values of -3 to -8.
Claim 3
Dependent Claim
13 words
The process of claim 1 in which the alkylene oxide is ethylene oxide.
Claim 4
Dependent Claim
13 words
The process of claim 1 in which the alkylene oxide is propylene oxide.
Claim 5
Dependent Claim
27 words
The process of claim 1 in which the clay contains, per gram, 0.2 to 0.6 milliequivalent of hydrogen ions having pK a values of -5 to -8.
Claim 6
Dependent Claim
50 words
In a process for preparing a polyether glycol by the copolymerization of tetrahydrofuran and ethylene oxide using an acid activated montmorillonite clay as a catalyst, the improvement of using Wyoming bentonite which contains, per gram, 0.2 to 0.6 milliequivalent of hydrogen ions having pK a values of -5 to -8.
Claim 7
Dependent Claim
50 words
In a process for preparing a polyether glycol by the copolymerization of tetrahydrofuran and ethylene oxide using an acid activated montmorillonite clay as a catalyst, the improvement of using Wyoming bentonite which contains, per gram, 0.2 to 0.6 milliequivalent of hydrogen ions having pK a values of -5 to -8.
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) | 1981-11-27 | 1982-05-29 | 1982-11-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-11-27 | 1986-05-29 | 1986-11-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-11-27 | 1990-05-29 | 1990-11-28 | $7700.00 | Window Closed / Lapsed |