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US4480124A
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Process for the purifying of polytetramethylene ether glycol or corresponding diester
Assignee: BASF SE
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Filing: 1982-03-11
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Granted: 1984-10-30
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Expires: 2002-03-11
Abstract
Abstract The subject invention relates to a process for purifying polytetramethylene ether glycol or the corresponding diester prepared by cationic polymerization of tetrahydrofuran comprising treating said glycol or diester with hydrogen in the presence of a hydrogen catalyst. The resulting products have a low color number.
Inventors
- 👤 Herbert Mueller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 08:51
CPC Classifications
C; C08; C08G; C08G65/00; C08G65/02; C08G65/30; C08G65/04; C08G65/06; C08G65/16; C08G65/20; C08G65/32; C08G65/321; C08G65/322
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
35 words
A process for purifying polytetramethylene ether glycol or its corresponding diester prepared by the cationic polymerization of tetrahydrofuran comprising treating said polytetramethylene ether glycol or diester with hydrogen in the presence of a hydrogenation catalyst.
Claim 2
Dependent Claim
35 words
A process for purifying polytetramethylene ether glycol or its corresponding diester prepared by the cationic polymerization of tetrahydrofuran comprising treating said polytetramethylene ether glycol or diester with hydrogen in the presence of a hydrogenation catalyst.
Claim 3
Dependent Claim
26 words
The process of claim 1 wherein the hydrogenation catalyst is selected from the group consisting of nickel, cobalt, copper, iron, ruthenium, palladium, platinum, and oxides thereof.
Claim 4
Dependent Claim
33 words
The process of claim 2 wherein said catalyst is supported on a fixed bed composed of a compound selected from the group consisting of aluminum oxide, silicon oxide, pumice, bentonite, and magnesium silicate.
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) | 1987-10-30 | 1988-04-30 | 1988-10-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-10-30 | 1992-04-30 | 1992-10-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-10-30 | 1996-04-30 | 1996-10-30 | $7700.00 | Window Closed / Lapsed |