US5919875A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of preparing syndiotactic 1,2-polybutadiene with a chromium-based catalyst system
Assignee: Bridgestone Corp
•
Filing: 1998-10-14
•
Granted: 1999-07-06
•
Expires: 2018-10-14
Abstract
Abstract A process for polymerizing 1,3-butadiene into syndiotactic 1,2-polybutadiene is described using a catalyst system comprising (a) a chromium-containing compound, (b) an organoaluminum hydride, and (c) a hydrogen phosphite. The use of the catalyst system avoids the use of environmentally detrimental components such as carbon disulfide and halogenated solvents. The syndiotactic 1,2-polybutadiene can be used as a plastic or as an additive for rubber compositions wherein it can crosslink with conventional rubbers using conventional crosslinking agents.
Inventors
- 👤 Steven Luo
- 👤 Michael W. Hayes
- 👤 Dennis R. Brumbaugh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 07:21
CPC Classifications
C; C08; C08F; C08F136/00; C08F136/02; C08F136/04; C08F136/06; C08F2410/00; C08F2410/01
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
34 words
A process for preparing syndiotactic 1,2-polybutadiene, comprising: polymerizing 1,3-butadiene in the presence of a catalyst system comprising catalytically effective amounts of: (a) a chromium-containing compound, (b) an organoaluminum hydride, and (c) a hydrogen phosphite.
Claim 2
Dependent Claim
34 words
A process for preparing syndiotactic 1,2-polybutadiene, comprising: polymerizing 1,3-butadiene in the presence of a catalyst system comprising catalytically effective amounts of: (a) a chromium-containing compound, (b) an organoaluminum hydride, and (c) a hydrogen phosphite.
Claim 3
Dependent Claim
30 words
A process according to claim 1, wherein said chromium-containing compound is a chromium carboxylate, chromium β-ketonate, chromium alkoxide, chromium aryloxide, chromium halide, chromium pseudo-halide, or organochromium compound or combinations thereof.
Claim 4
Dependent Claim
92 words
A process according to claim 1, wherein said hydrogen phosphite has the following keto-enol tautomeric structures: ##STR3## or mixtures thereof wherein R 1 and R 2 are independently an alkyl group having 1 to 20 carbon atoms, a cycloalkyl or allyl group having 3 to 20 carbon atoms, or an aryl, aralkyl, or alkaryl group having 6 to 20 carbon atoms and R 3 is a divalent alkylene or substituted alkylene group having 2 to 20 carbon atoms, or a divalent arylene or substituted arylene group having 6 to 20 carbon atoms.
Claim 5
Dependent Claim
31 words
A process according to claim 1, wherein said chromium-containing compound is present in the polymerization in an amount from about 0.01 to about 2 mmol per 100 g of said 1,3-butadiene.
Claim 6
Dependent Claim
30 words
A process according to claim 1, wherein said organoaluminum hydride and said chromium-containing compound are present in said catalyst system in a molar ratio (Al/Cr) from about 1:1 to 100:1.
Claim 7
Dependent Claim
25 words
A process according to claim 5, wherein said molar ratio of said organoaluminum hydride to said chromium-containing compound (Al/Cr) is from about 3:1 to 50:1.
Claim 8
Dependent Claim
31 words
A process according to claim 1, wherein said hydrogen phosphite and said chromium-containing compound are present in said catalyst system in a molar ratio (P/Cr) from about 0.5:1 to about 50:1.
Claim 9
Dependent Claim
26 words
A process according to claim 7, wherein said molar ratio of said hydrogen phosphite to said chromium-containing compound (P/Cr) is from about 1:1 to about 25:1.
Claim 10
Dependent Claim
22 words
A process according to claim 1, wherein the polymerization is conducted at a temperature from about -10° C. to about 100° C.
Claim 11
Dependent Claim
15 words
A process according to claim 1, wherein the polymerization is conducted in a hydrocarbon medium.
Claim 12
Dependent Claim
26 words
A process according to claim 10, wherein said medium comprises from about 5% to about 50% by weight of 1,3-butadiene at the beginning of said polymerization.
Claim 13
Dependent Claim
24 words
A process according to claim 1, wherein the polymerization is conducted in a hydrocarbon medium and said catalyst system is soluble in said medium.
Claim 14
Dependent Claim
31 words
A process according to claim 12, wherein said chromium-containing compound is present in the polymerization in an amount from about 0.02 to about 1 mmol per 100 g of said 1,3-butadiene.
Claim 15
Dependent Claim
27 words
A process according to claim 6, wherein said hydrogen phosphite and said chromium-containing compound are present in a molar ratio (P/Cr) from about 1:1 to about 25:1.
Claim 16
Dependent Claim
31 words
A process according to claim 14, wherein said chromium-containing compound is present in the polymerization in an amount from about 0.02 to about 1 mmol per 100 g of said 1,3-butadiene.
Claim 17
Dependent Claim
19 words
A process according to claim 1, wherein the polymerization is conducted in the presence of a molecular weight regulator.
Claim 18
Dependent Claim
23 words
A process according to claim 1, wherein said chromium-containing compound comprises a chromium carboxylate, chromium β-diketonate, or a chromium alkoxide or combinations thereof.
Claim 19
Dependent Claim
14 words
A process according to claim 1, wherein said organoaluminum hydride comprises a dialkylaluminum hydride.
Claim 20
Dependent Claim
15 words
A process according to claim 1, wherein said hydrogen phosphite comprises a dialkyl hydrogen phosphite.
References Cited (Backward Citations)
US3498963A
Cited
US3778424A
Cited
JPS4864178A
Cited
US4182813A
Cited
US4168357A
Cited
US4168374A
Cited
US4751275A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-07-05 | 2003-01-04 | 2003-07-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-07-05 | 2007-01-04 | 2007-07-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-07-05 | 2011-01-04 | 2011-07-06 | $7700.00 | Window Closed / Lapsed |