Claims
- 1. A catalyst system for the polymerization of olefins which comprises a metallocene component and a methylaluminoxane which, when hydrolyzed, evolves hydrolysis products comprising methane and C.sub.2 or higher alkanes.
- 2. A catalyst system as claimed in claim 1 wherein the metallocene component comprises an organometallic coordination compound of a Group IVB or Group VB metal.
- 3. A catalyst system as claimed in claim 2 wherein the organometallic coordination compound comprises a zirconium compound.
- 4. A catalyst system as claimed in claim 1 wherein the C.sub.2 or higher alkane hydrolysis product is selected from the group consisting of isobutane, n-butane, and n-hexane.
- 5. A catalyst system as claimed in claim 1 wherein the methane content from the hydrolysis ranges from about 20% to about 80%, by weight.
- 6. A catalyst system as claimed in claim 2 wherein the methane content from the hydrolysis ranges from about 20% to about 80%, by weight, and the C.sub.2 or higher alkane hydrolysis product constitutes the remainder and is selected from the group consisting of isobutane, n-butane, and n-hexane.
- 7. A catalyst system as claimed in claim 1 wherein methylaluminoxane is formed by reaction of a tetraalkyldialuminoxane containing C.sub.2 or higher alkyl groups with an amount of trimethylaluminum that is not in stoichiometric excess.
- 8. A catalyst system as claimed in claim 7 wherein the molar amount of tetraalkyldialuminoxane to trimethylaluminum ranges from about 0.1:1 to no more than 1:1 and the reaction is conducted at temperatures ranging from about -10.degree. C. to about 150.degree. C.
- 9. A catalyst system as claimed in claim 7 wherein the alkyl groups are isobutyl groups.
- 10. A catalyst system as claimed in claim 1 wherein the methylaluminoxane is formed by the reaction of a tetraalkyldialuminoxane containing C.sub.2 or higher alkyl groups with water to form a polyalkylaluminoxane which is then reacted with trimethylaluminum.
- 11. A catalyst system as claimed in claim 10 wherein the alkyl groups are isobutyl groups.
- 12. A catalyst system as claimed in claim 1 wherein the methylaluminoxane is formed by the reaction of a polyalkylaluminoxane containing C.sub.2 or higher alkyl groups with trimethylaluminum and then with water.
- 13. A catalyst system as claimed in claim 12 wherein the alkyl groups are isobutyl groups.
- 14. A catalyst system as claimed in claim 13 wherein the molar ratio of trimethylaluminum to polyalkylaluminoxane ranges from about 0.1 to about 10 at temperatures of from about -20.degree. C. to about 50.degree. C.
- 15. A catalyst system as claimed in claim 14 wherein the molar ratio of trimethylaluminum to polyalkylaluminoxane ranges from about 0.1 to about 10 at temperatures of from about -20.degree. C. to about 50.degree. C.
Parent Case Info
This is a division of application Ser. No. 279,377 filed Dec. 2, 1988 and now U.S. Pat. No. 4,960,878.
US Referenced Citations (4)
Divisions (1)
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Number |
Date |
Country |
Parent |
279377 |
Dec 1988 |
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