Patent EP0272584A2 successfully refreshed from Google Patents.
EP0272584A2
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Process for producing crystalline vinyl aromatic polymers having a predominantly syndiotactic structure
Assignee: Montedison SpA
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Filing: 1987-12-15
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Granted: —
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Expires: 2007-12-15
Abstract
Abstract A process for the production of predominantly syndiotactic vinyl aromatic polymers by polymerizing or copolymerizing vinyl aromatic monomers such as styrene or styrene derivatives in the presence of a catalyst system comprising the product of the reaction between: a) a compound of a transition metal (M) different from titanium and containing at least one M-O, M-C, M-N, M-P, M-S or M-halogen bond, and b) an organoaluminium compound containing at least one oxygen atom bound to the aluminium atom or located between two aluminium atoms. Compounds a) and b) can be used as such or supported on a carrier.
Inventors
- 👤 Enrico Albizatti
- 👤 Umberto Dr. Giannini
- 👤 Giovanni Dr. Giunchi
- 👤 Romano Mazzocchi
- 👤 Luigi Dr. Resconi
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-02 12:46
CPC Classifications
C; C08; C08F; C08F12/00; C08F12/02; C08F12/04; C08F10/00; C08F12/06; C08F12/08; Y; Y10; Y10S; Y10S526/00; Y10S526/941
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
99 words
A process for producing crystalline vinyl aromatic polymers having a predominantly syndiotactic structure, which comprises polymerizing the vinyl aromatic monomers, either alone or in admixture with up to 30 % of another copolymerizable ethylenically unsaturated monomer, in the presence of catalytic amounts of a catalyst system comprising the product of the reaction between: a) a compound of a transition metal (M) different from titanium and containing at least one M-O; M-C; M-N; M-P; M-S or M-halogen bond; and b) an organoaluminium compound containing at least one oxygen atom, bound to one aluminium atom or located between two Al atoms.
Claim 2
Dependent Claim
99 words
A process for producing crystalline vinyl aromatic polymers having a predominantly syndiotactic structure, which comprises polymerizing the vinyl aromatic monomers, either alone or in admixture with up to 30 % of another copolymerizable ethylenically unsaturated monomer, in the presence of catalytic amounts of a catalyst system comprising the product of the reaction between: a) a compound of a transition metal (M) different from titanium and containing at least one M-O; M-C; M-N; M-P; M-S or M-halogen bond; and b) an organoaluminium compound containing at least one oxygen atom, bound to one aluminium atom or located between two Al atoms.
Claim 3
Dependent Claim
28 words
The process of claim 1, wherein the transition metal compound and the organoaluminium compound are supported on organic or inorganic carriers, such as SiO₂, Al₂O₃ or Mg halides.
Claim 4
Dependent Claim
28 words
The process of claim 1 or 2, wherein the molar ratio of organoaluminium compound to transition metal compound is from 1 to 1000, preferably from 10 to 200.
Claim 5
Dependent Claim
26 words
The process of any of the preceding claims, wherein the concentration of the organoaluminium compound ranges from 10⁻⁴ to 1 mole/liter, based on the reaction mixture.
Claim 6
Dependent Claim
29 words
The process of any of the preceding claims, wherein the transition metal compound is selected from bis-indenyl zirconium dichloride; zirconium tetrabenzyl; ZrCl(O-i-C₃H₇)₃; vanadyl bis-acetylacetonate; vanadium triacetylacetonate; zirconium-dibenzyl-dichloride,ZrCl(OC₄H₉)₃ and Ni(1,5-cyclooctadiene)₂.
Claim 7
Dependent Claim
111 words
The process of any of the preceding claims, wherein the organoaluminium compound is selected from: wherein: n is 0 or an integer from 1 to 40, preferably from 10 to 30; R can be: an alkyl radical containing 1 to 20 carbon atoms, an aryl radical containing 6 to 20 carbon atoms, an arylalkyl radical containing 7 to 20 carbon atoms or a cycloalkyl radical containing 3 to 20 carbon atoms, a O-Rʹ radical in which Rʹ may be an alkyl radical containing 1 to 8 carbon atoms or an aryl radical containing 6 to 20 carbon atoms; or a halogen, provided that not all radicals R are halogen or O-Rʹ.
Claim 8
Dependent Claim
30 words
The process according to claim 6, wherein the organoaluminium compounds are blended with aluminium trialkyls or aluminium alkyl halides, wherein the alkyl groups contain from 1 to 8 carbon atoms.
Claim 9
Dependent Claim
18 words
The process of claim 6, wherein the organoaluminium compound is the straight methylaluminoxane (A) with n = 20.
Claim 10
Dependent Claim
18 words
The process of claim 6, wherein the organoaluminium compound is the cyclic methylaluminoxane (B) with n = 20.
Claim 11
Dependent Claim
40 words
The process according to anyone of the preceding claims, wherein the vinyl aromatic monomer is styrene or a styrene derivative, e.g. selected from alkylstyrene, halogenated styrene, vinylnaphthalene and vinyltetrahydronaphthalene, each containing from 9 to 12 carbon atoms in the molecule.
References Cited (Backward Citations)
No citation records indexed.
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