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US4528389A
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Pentacoordinate silyl enolates and their use as polymerization initiators
Assignee: EIDP Inc
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Filing: 1984-06-12
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Granted: 1985-07-09
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Expires: 2004-06-12
Abstract
Abstract Pentacoordinate silyl enolate and the use thereof as an initiator, without a co-catalyst, in the polymerization of methacrylic monomers, such as methacrylate esters.
Inventors
- 👤 William B. Farnham
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 15:04
CPC Classifications
C; C08; C08F; C08F20/00; C08F20/02; C08F20/10; C08F20/12; C07; C07F; C07F7/00; C07F7/02; C07F7/08; C07F7/18; C07F7/1804
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
76 words
Pentacoordinate silyl enolate of the formula ##STR11## each of R 2 and R 3 is independently selected from H or C 1-5 alkyl; provided, however, both R 2 and R 3 are not H; R 4 is a hydrocarbyl radical which is an aliphatic, alicyclic, aromatic or mixed aliphatic-aromatic radical containing up to 20 carbon atoms, optionally containing one or more ether oxygen atoms within aliphatic segments thereof; and M is lithium, sodium, potassium or cesium.
Claim 2
Dependent Claim
76 words
Pentacoordinate silyl enolate of the formula ##STR11## each of R 2 and R 3 is independently selected from H or C 1-5 alkyl; provided, however, both R 2 and R 3 are not H; R 4 is a hydrocarbyl radical which is an aliphatic, alicyclic, aromatic or mixed aliphatic-aromatic radical containing up to 20 carbon atoms, optionally containing one or more ether oxygen atoms within aliphatic segments thereof; and M is lithium, sodium, potassium or cesium.
Claim 3
Dependent Claim
21 words
Pentacoordinate silyl enolate of claim 1 wherein R 2 , R 3 and R 4 are methyl and M is Li.
Claim 4
Dependent Claim
22 words
Pentacoordinate silyl enolate of claim 1 wherein R 4 is menthyl, R 2 and R 3 are methyl and M is Li.
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) | 1988-07-08 | 1989-01-07 | 1989-07-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-07-08 | 1993-01-07 | 1993-07-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-07-08 | 1997-01-07 | 1997-07-09 | $7700.00 | Window Closed / Lapsed |