Process for producing crystalline poly-α-olefins with a monocyclopentadienyl transition metal catalyst system

Abstract

The invention is a catalytic process using a Group IV B transition metal component and an alumoxane component to polymerize α-olefins to produce high crystallinity and high molecular weight poly-α-olefins.

1. A process for producing crystalline poly-α-olefins comprising the steps of
 (i) contacting an α-olefin monomer at a temperature and pressure sufficient to polymerize such monomer with a catalyst system comprising;  comprising:
 (A) an alumoxane, and  
 (B) a group  Group IV-B transition metal component of the formula 
                 
 
  wherein M is Zr, Hf or Ti in its highest formal oxidation state;  
 
 R is a substituent group with “x” denoting the degree of substitution (x=0, 1, 2, 3 or 4) and each R is, independently, a radical selected from a group consisting of C 1 -C 20  hydrocarbyl radicals, substituted C 1 -C 20  hydrocarbyl radicals wherein one or more hydrogen atoms is replaced by a halogen radical, an amido radical, a phosphido radical, an alkoxy radical or any  other radical containing a Lewis acidic or basic functionality, C 1 -C 20  hydrocarbyl-substituted metalloid radicals wherein the metalloid is selected from the Group IV A of the Periodic Table of Elements, and halogen radicals, amido radicals, phosphido radicals, alkoxy radicals, alkylborido radicals or a radical  other radicals containing a Lewis acidic or basic functionality, or at least two adjacent R-groups are joined forming C 4 -C 20  ring to give a saturated or unsaturated polycyclic cyclopentadienyl ligand;  
 (JR′ z-2 ) is a heteroatom ligand in which J is an element with a coordination number of three from Group V A or an element with a coordination number of two from Group VI A of the Periodic Table of Elements, and each R′ is, independently  R′ is a radical selected from a group consisting of C 1 -C 20  hydrocarbyl radicals, substituted C 1 -C 20  hydrocarbyl radicals where one or more hydrogen atom is replaced by a halogen radical, an amido radical, a phosphido radical, and  an alkoxy radical or a  other radical containing a Lewis acidic or basic functionality, and “z” is the coordination number of the element J;  
 each Q is, independently, any univalent anionic ligand or two Q's are a divalent anionic chelating ligand;  ligand, provided that Q is not a substituted or unsubstituted cyclopentadienyl ring; 
 T is a covalent bridging group containing a Group IV A or V A element;  
 L is a neutral Lewis base where “w” denotes a number from 0 to 3;  
 (ii) recovering a crystalline poly-α-olefin.  
 
     
     
       2. The process of  claim 1 , wherein the Group IV-B transition metal component is of the formula: 
                 
 
       wherein R 1  and R 2  are, independently, a  C 1  to C 20  hydrocarbyl radicals, or substituted C 1  to C 20  hydrocarbyl radicals wherein one or more hydrogen atom is replaced by a halogen atom; R 1  and R 2  may also be joined forming a C 3  to C 20  ring. 
     
     
       3. The processes of claims  1  or  2  wherein J is nitrogen. 
     
     
       4. The process of  claim 3  wherein R is a C 1  to C 20  hydrocarbyl radical, “x” is 1 and R′ is a C 6  to C 20  cyclohydrocarbyl radical or an aromatic radical. 
     
     
       5. The process of  claim 1  wherein the Group IV-B transition metal component is of the formula: 
                 
  wherein R 1  and R 2  are independently a  C 1  to C 20  hydrocarbyl radicals, or substituted C 1  to C 20  hydrocarbyl radicals wherein one or more hydrogen atom is replaced by a halogen atom; R 1  and R 2  may also be joined forming a C 3  to C 20  ring.  
 
     
     
       6. The process of  claim 5  where  wherein J is nitrogen. 
     
     
       7. The process of  claim 6  wherein R′ is an alkyl radical or cyclic  cycloalkyl radical. 
     
     
       8. The process of  claim 1  wherein the Group IV-B transition metal component is of the formula  formula:
                 
 
       wherein
 “x” is  0 ,  1  or  2 ; 
 R 1  and R 2  are independently a  C 1  to C 20  hydrocarbyl radicals, or substituted C 1  to C 20  hydrocarbyl radicals wherein one or more hydrogen atom is replaced by a halogen atom; R 1  and R 2  may also be joined forming a C 3  to C 20  ring.  
 
     
     
       9. The process of  claim 8  wherein J is nitrogen. 
     
     
       10. The process of  claim 9  wherein R′ is a cycloalkyl radical. 
     
     
       11. The process of  claim 2 ,  5 , or  8  wherein M is titanium. 
     
     
       12. The process of claims  2  or  5  wherein M is hafnium or zirconium. 
     
     
       13. The process of  claim 1  wherein T is a covalent bridging group containing silicon, J is nitrogen and when R is an alkyl radical, R′ is a cyclohydrocarbyl or aromatic radical, and  or when “x” is  2  or  4  and the R substituents form a polycyclic ring system, R′ is an alkyl or cyclohydrocarbyl radical.