US4500705A
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Method for reducing oligomeric cyclic ether content of a polymerizate
Assignee: EIDP Inc
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Filing: 1984-01-09
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Granted: 1985-02-19
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Expires: 2004-01-09
Abstract
Abstract The oligomeric cyclic ether content of a tetrahydrofuran-, an alkylene oxide-, or a tetrahydrofuran/alkylene oxide polymerizate can be reduced by bringing the polymerizate into contact with an aliphatic- or cycloaliphatic hydrocarbon of 6-8 carbon atoms, and separating the polymerizate and the hydrocarbon phases.
Inventors
- 👤 Harry B. Copelin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 16:46
CPC Classifications
C; C08; C08G; C08G65/00; C08G65/02; C08G65/04; C08G65/06; C08G65/16; C08G65/20; C08G65/30
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
83 words
A method for reducing the oligomeric cyclic ether content of a tetrahydrofuran-, an alkylene oxide-, or a tetrahydrofuran/alkylene oxide polymerizate, the method comprising bringing the polymerizate into contact with an aliphatic- or cycloaliphatic hydrocarbon of 6-8 carbon atoms, or an aliphatic- or cycloaliphatic hydrocarbon of 6-8 carbon atoms substituted with one or more methyl or ethyl groups, for a time sufficient to bring the oligomeric cyclic ether content of the polymerizate to the desired level, and then separating the polymerizate and the hydrocarbon.
Claim 2
Independent Claim
83 words
A method for reducing the oligomeric cyclic ether content of a tetrahydrofuran-, an alkylene oxide-, or a tetrahydrofuran/alkylene oxide polymerizate, the method comprising bringing the polymerizate into contact with an aliphatic- or cycloaliphatic hydrocarbon of 6-8 carbon atoms, or an aliphatic- or cycloaliphatic hydrocarbon of 6-8 carbon atoms substituted with one or more methyl or ethyl groups, for a time sufficient to bring the oligomeric cyclic ether content of the polymerizate to the desired level, and then separating the polymerizate and the hydrocarbon.
Claim 3
Dependent Claim
15 words
The method of claim 1 in which the hydrocarbon is n-heptane, n-octane, cyclohexane, or methylcyclohexane.
Claim 4
Dependent Claim
11 words
The method of claim 1 in which the hydrocarbon is n-heptane.
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) | 1988-02-19 | 1988-08-20 | 1989-02-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-02-19 | 1992-08-20 | 1993-02-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-02-19 | 1996-08-20 | 1997-02-19 | $7700.00 | Window Closed / Lapsed |