US4751275A
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Process and catalyst for the preparation of syndiotactic 1,2,-polybutadiene
Assignee: BAYER KAUTSCHUK A CORP OF GERMANY GmbH
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Filing: 1986-10-16
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Granted: 1988-06-14
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Expires: 2006-10-16
Abstract
Abstract Syndiotactic 1,2-polybutadiene of high quality may be obtained in excellent yield by solution polymerization of butadiene-(1,3) in hydrocarbons, using organometallic mixed catalysts composed of trialkylaluminium, hydrocarbon-soluble chromium-III compounds and a dialkylphosphite corresponding to the formula ##STR1## wherein R denotes straight chained or branched C 1 -C 8 -alkyl and R 1 , R 2 and R 3 denote methyl or ethyl or R and R 1 together form a methylene group.
Inventors
- 👤 Josef Witte
- 👤 Gerd Sylvester
- 👤 Bernd Stollfuss
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 23:31
CPC Classifications
C; C08; C08F; C08F136/00; C08F136/02; C08F136/04; C08F136/06; Y; Y10; Y10S; Y10S526/00; Y10S526/903
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
67 words
Process for the preparation of syndiotactic 1,2-polybutadiene by solution polymerisation of butadiene-(1,3) in hydrocarbons, using organometallic mixed catalysts of trialkylaluminium, chromium-III compounds which are soluble in hydrocarbons, and dialkylphosphites, characterised in that the dialkylphosphites used correspond to the general formula (I) ##STR4## wherein R denotes straight chained or branched C 1 -C 8 -alkyl and R 1 , R 2 and R 3 denote methyl or ethyl.
Claim 2
Dependent Claim
67 words
Process for the preparation of syndiotactic 1,2-polybutadiene by solution polymerisation of butadiene-(1,3) in hydrocarbons, using organometallic mixed catalysts of trialkylaluminium, chromium-III compounds which are soluble in hydrocarbons, and dialkylphosphites, characterised in that the dialkylphosphites used correspond to the general formula (I) ##STR4## wherein R denotes straight chained or branched C 1 -C 8 -alkyl and R 1 , R 2 and R 3 denote methyl or ethyl.
Claim 3
Dependent Claim
33 words
Process according to claim 1, characterised in that polymerisation is carried out in the presence of from 100 to 10,000 ppm of butadiene-(1,2), based on the quantity of butadiene-(1,3) put into the process.
Claim 4
Dependent Claim
22 words
Process according to claim 1, characterised in that polymerisation is carried out under an inert protective gas at 30° to 130° C.
Claim 5
Dependent Claim
23 words
A process according to claim 1, wherein the polymerisation is carried out in the presence of from 500 to 3,000 ppm of butadiene-(1,2).
Claim 6
Dependent Claim
19 words
Catalyst based on trialkylaluminium, a hydrocarbon-soluble chromium-III compound and dialkylphosphite, characterised in that the dialkylphosphite is di-neopentylphosphite or neopentylmethylphosphite.
Claim 7
Dependent Claim
19 words
Catalyst based on trialkylaluminium, a hydrocarbon-soluble chromium-III compound and dialkylphosphite, characterised in that the dialkylphosphite is di-neopentylphosphite or neopentylmethylphosphite.
Claim 8
Dependent Claim
12 words
Catalyst according to claim 5 characterised in that the dialkylphosphite is di-neopentylphosphite.
Claim 9
Dependent Claim
17 words
Catalyst according to claim 5 consisting of (a) triethylaluminium, (b) chromium-III-stearate, -octanoate or -versatate and (c) di-neopentylphosphite.
Claim 10
Dependent Claim
24 words
Catalyst according to claim 5 in which the molar ratio of aluminium compound to chromium-III compound to phosphite is in the range of 5-50:1:2-15.
Claim 11
Dependent Claim
25 words
A catalyst according to claim 5, wherein the molar ratio of aluminum compound to chromium III compound to phosphite is in the range of 10-25:1:3-10.
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) | 1991-06-14 | 1991-12-14 | 1992-06-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-06-14 | 1995-12-14 | 1996-06-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-06-14 | 1999-12-14 | 2000-06-14 | $7700.00 | Window Closed / Lapsed |