Patent US5312794A successfully refreshed from Google Patents.
US5312794A
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Catalyst system for olefin polymerization
Assignee: Shell USA Inc
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Filing: 1992-12-29
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Granted: 1994-05-17
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Expires: 2012-12-29
Abstract
Abstract A catalyst system and process for the polymerization of cyclic olefins, such as dicyclopentadiene, are disclosed. The catalyst system contains a transition metal hydrotrispyrazolylborate complex having the formula: Tp--M--L.sub.3 wherein Tp is a hydrotrispyrazolylborate ligand, M is tungsten or molybdenum, and L is independently a ligand selected from the group consisting of oxo, phenoxy, alkoxy, and halides, provided that at least one L is a halide, and a co-catalyst.
Inventors
- 👤 Donald R. Kelsey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 11:17
CPC Classifications
C; C08; C08G; C08G61/00; C08G61/02; C08G61/04; C08G61/06; C08G61/08
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
64 words
A cyclic olefin polymerization catalyst system comprising: (a) a transition metal hydrotrispyrazolylborate complex having the formula: Tp--M--L.sub.3 wherein Tp is a hydrotrispyrazolylborate ligand, M is tungsten or molybdenum, and L is independently a ligand selected from the group consisting of oxo, phenoxy, alkoxy, pyrazole, and halides provided that at least one L is a halide; and (b) a co-catalyst for ring opening cycloolefin polymerization.
Claim 2
Dependent Claim
64 words
A cyclic olefin polymerization catalyst system comprising: (a) a transition metal hydrotrispyrazolylborate complex having the formula: Tp--M--L.sub.3 wherein Tp is a hydrotrispyrazolylborate ligand, M is tungsten or molybdenum, and L is independently a ligand selected from the group consisting of oxo, phenoxy, alkoxy, pyrazole, and halides provided that at least one L is a halide; and (b) a co-catalyst for ring opening cycloolefin polymerization.
Claim 3
Dependent Claim
11 words
The catalyst system of claim 1 in which M is tungsten.
Claim 4
Dependent Claim
12 words
The catalyst system of claim 1 in which L is a halide.
Claim 5
Dependent Claim
27 words
The catalyst system of claim 1 in which Tp is a hydrotrispyrazolylborate having the formula ##STR3## wherein R is independently selected from hydrogen and C 1-8 alkyl.
Claim 6
Dependent Claim
24 words
The catalyst system of claim 4 in which the cocatalyst is selected from the group consisting of organotin hydrides, borohydrides, orgamozinc and organoaluminum compounds.
Claim 7
Dependent Claim
14 words
The catalyst system of claim 5 in which the cocatalyst is a organotin hydride.
Claim 8
Dependent Claim
14 words
The catalyst system of claim 5 in which the cocatalyst is a organoaluminum compound.
Claim 9
Dependent Claim
18 words
The catalyst system of claim 6 further comprising a promoter to promote the activity of said catalyst system.
Claim 10
Dependent Claim
14 words
The catalyst system of claim 8 in which the promoter is a boron halide.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-05-16 | 1997-11-15 | 1998-05-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-05-16 | 2001-11-15 | 2002-05-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-05-16 | 2005-11-15 | 2006-05-17 | $7700.00 | Window Closed / Lapsed |