Oligomeric metallocenes and their use

Abstract

A process for producing a new metallocene comprising reacting a first bridged metallocene which has an olefinically unsaturated with about two molar equivalents of an alkali metal alkyl, catalyst systems resulting from the combination of the resulting metallocenes and a cocatalyst, and polymerization processes using such catalyst systems are disclosed.

That which is claimed:  
     
         1 . A process for producing a metalloncene comprising reacting a first bridged metallocene having an alkenyl group attached to the bridge with about two molar equivalents of an alkali metal alkyl having at least 4 carbon atoms.  
     
     
         2 . A process according to  claim 1  wherein the alkali metal alkyl is n-butyl lithium.  
     
     
         3 . A process according to  claim 2  wherein the alkenyl group is a straight chain alkenyl having 3 to 10 carbon atoms and terminal olefinic unsaturation.  
     
     
         4 . A process according to  claim 3  wherein the alkenyl group is but-3-enyl.  
     
     
         5 . A process according to  claim 4  wherein the metal of the first metalloncene is ziroconium.  
     
     
         6 . A process according to  claim 5  wherein the first metallocene used is 1-(9-fluorenyl)-I-(cyclopentadienyl)-1-(methyl)-1-(but-3-enyl) methane zirconium dichloride.  
     
     
         7 . A metallocene produced by the process of  claim 1 .  
     
     
         8 . A metallocene produced by the process of  claim 5 .  
     
     
         9 . An oligomeric matallocycle metallocene having repeating units of the formula  
       
         
           
           
               
               
           
         
       
       wherein L and L′ are the same or different and are selected from the group consisting of cyclopentadienyl, indenyl, and fluorenyl, either unsubstituted or substituted with one or more hydrocarbyl substituents, M is selected from Zr, Hf, and Ti.  
     
     
         10 . A metallocene according to  claim 9  wherein M is Zr.  
     
     
         11 . A process according to  claim 2  wherein there is a single carbon atom connecting L and L′ and attached to that carbon atom is at least one olefinically unsaturated substituent.  
     
     
         12 . A metallocene according to  claim 11  wherein L is cyclopentadienyl, L′ is fluorenyl, and Y is 1-(but-3-enyl)-1-(methyl) methylene.  
     
     
         13 . A catalyst system useful for the polymerization of olefins comprising the product resulting from the combination of the metallocene produced by the process of  claim 1  and an organometallic cocatalyst.  
     
     
         14 . A catalyst system useful for the polymerization of olefins comprising the product prepared by combining the metallocene produced by the process of  claim 1  and the organometallic cocatalyst and conducting a prepolymerization in the presence of an olefin to produce a particulate prepolymerized solid catalyst system.  
     
     
         15 . A catalyst system of  claim 14  wherein the cocatalyst comprises a pentafluorophenyl borate.  
     
     
         16 . A process for producing a polymer comprising contacting an olefin with the catalyst system of  claim 15  under polymerization conditions.  
     
     
         17 . A catalyst system of  claim 14  wherein the cocatalyst comprises an alkylaluminoxane.  
     
     
         18 . A process for producing a polymer comprising contacting an olefin with the catalyst system of  claim 17  under polymerization conditions.  
     
     
         19 . A catalyst system useful for the polymerization of olefins comprising the product resulting from the combination of the metallocene produced by the process of  claim 11  and an organometallic cocatalyst.  
     
     
         20 . A catalyst system according to  claim 19  wherein the alkenyl group of the bridge of the first metallocene is but-3-enyl.  
     
     
         21 . A catalyst system according to  claim 20  wherein the metal of the first metallocene is zirconium.  
     
     
         22 . A catalyst system according to  claim 21  wherein the first metallocene is 1-(9-fluorenyl)-1-(cyclopentadienyl)-1-(methyl)-1-(but-3-enyl) methane zirconium dichloride and the cocatalyst is methylaluminoxane.  
     
     
         23 . A process for producing a polymer comprising contacting an olefin with the catalyst system of  claim 22  under polymerizable conditions.