US4228272A
Expired / Lapsed
US
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Method of catalytically preparing tetrahydrofuran/alkylene oxide polymerizates using a montmorillonite clay as the catalyst
Assignee: EIDP Inc
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Filing: 1979-03-27
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Granted: 1980-10-14
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Expires: 1999-03-27
Abstract
Abstract A polymerizate of THF and an alkylene oxide is prepared by catalytic polymerization, using as a catalyst an acid-activated montmorillonite clay having a pore volume of 0.4-0.8 cubic centimeter per gram, a surface area of 220-260 square meters per gram and an average pore diameter of 0.1-0.3 micron.
Inventors
- 👤 Thomas W. Del Pesco
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 14:35
CPC Classifications
C; C08; C08G; C08G65/00; C08G65/02; C08G65/04; C08G65/06; C08G65/16; C08G65/20; C08G65/26; C08G65/2642; C08G65/2645; C08G65/2654; C08G65/2657
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
48 words
In a process for catalytically preparing a tetrahydrofuran/alkylene oxide polymerizate, the improvement comprising using as the catalyst an acid-activated montmorillonite clay having a pore volume of 0.4-0.8 cubic centimeter per gram, a surface area of 220-260 square meters per gram, and an average pore diameter of 0.1-0.3 micron.
Claim 2
Dependent Claim
48 words
In a process for catalytically preparing a tetrahydrofuran/alkylene oxide polymerizate, the improvement comprising using as the catalyst an acid-activated montmorillonite clay having a pore volume of 0.4-0.8 cubic centimeter per gram, a surface area of 220-260 square meters per gram, and an average pore diameter of 0.1-0.3 micron.
Claim 3
Dependent Claim
12 words
The process of claim 1 wherein the alkylene oxide is ethylene oxide.
Claim 4
Dependent Claim
13 words
The process of claim 1 wherein the alkylene oxide is a propylene oxide.
References Cited (Backward Citations)
GB854958A
Cited
US3201197A
Cited
US3321412A
Cited
US3328467A
Cited
US3412039A
Cited
US3997563A
Cited
US4127513A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-10-14 | 1984-04-14 | 1984-10-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-10-14 | 1988-04-14 | 1988-10-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-10-14 | 1992-04-14 | 1992-10-14 | $7700.00 | Window Closed / Lapsed |