Process for the preparation of polyolefins

Abstract

A process for the preparation of an olefin polymer by polymerization or copolymerization of an olefin of the formula R a —CH═CH—R b , in which R a and R b are identical or different and are a hydrogen atom or a hydrocarbon radical having 1 to 14 carbon atoms or R a and R b , together with the atoms connecting them, can form a ring, at a temperature of from −60° to 200° C., at a pressure of from 0.5 to 100 bar, in solution, in suspension or in the gas phase, in the presence of a catalyst formed from a metallocene in the meso-form or a meso:rac mixture, with meso:rac>1:99, as transition-metal compound and a cocatalyst, wherein the metallocene is a compound of the formula I, in which M 1 is Zr or Hf, R 1 and R 2 are identical or different and are methyl or chlorine, R 3 and R 6 are identical or different and are methyl, isopropyl, phenyl, ethyl or trifluoromethyl, R 4 and R 5 are hydrogen or as defined for R 3 and R 6 , or R 4 forms an aliphatic or aromatic ring with R 6 , or adjacent radicals R 4 form a ring of this type, and R 7 is a radical, and m plus n is zero or 1.

1. A compound of the formula I in its pure meso-form or as a meso:rac>1:99 mixture, 
                 
 
       in which
 M 1  is a metal from group IVb, Vb or VIb of the Periodic Table,  
 R 1  and R 2  are identical or different and are a hydrogen atom, a C 1 -C 10 -alkyl group, a C 1 -C 10 -alkoxy group, a C 6 -C 10 -aryl group, a C 6 -C 10 -aryloxy group, a C 2 -C 10 -alkenyl group, a C 7 -C 40 -arylalkyl group, a C 7 -C 40 -alkylaryl group, a C 8 -C 40 -arylalkenyl group, or a halogen atom,  
 the radicals R 4  and R 5  are identical or different and are a hydrogen atom, a halogen atom, a C 1 -C 10 -alkyl group, which may be halogenated, a C 6 -C 10 -aryl group, which may be halogenated, or an —NR 10   2 , —SR 10 , —OSiR 10   3 , —SiR 10   3  or —PR 10   2  radical in which R 10  is a halogen atom, a C 1 -C 10 -alkyl group or a C 6 -C 10 -aryl group,  
 R 3  and R 6  are identical or different and are as defined as for R 4 , with the proviso that R 3  and R 6  are not hydrogen,  
 or two or more of the radicals R 3  to R 6 , together with the atoms connecting them, form a ring system,                   
 >BR 11 , >AlR 11 , —Ge—, —Sn—, —O—, —S—, >SO, >SO 2 , >NR 11 , >CO, >PR 11  or >P(O)R 11 , 
 
       where
 R 11  , R 12  and R 13  are identical or  and R 12    are  different and are a hydrogen atom, a halogen atom, a C 1 -C 10 -alkyl group, a C 1 -C 10 -fluoroalkyl group, a C 6 -C 10 -aryl group, a C 6 -C 10 -fluoroaryl group, a C 1 -C 10 -alkoxy group, a C 2 -C 10 -alkenyl group, a C 7 -C 40 -arylalkyl group, a C 8 -C 40 -arylalkenyl group or a C 7 -C 40 -alkylaryl group,  
 R 13    is a hydrogen atom, a halogen atom, a C   1   -C   10 - alkyl group, a C   1   -C   10 - fluoroalkyl group, a C   6   -C   10 - aryl group, a C   6   -C   10 - fluoroaryl group, a C   1   -C   10 - alkoxy group, a C   2   -C   10 - alkenyl group, a C   7   -C   40 - arylalkyl group, a C   8   -C   40 - arylalkenyl group or a C   7   -C   40 - alkylaryl group,   
 or R 11  and R 12  or R 11  and R 13 , in each case together with the atoms connecting them, form a ring,  
 M 2  is silicon, germanium or tin,  
 R 8  and R 9  are identical or different and are as defined for R 11 , and  
 m and n are identical or different and are zero, 1 or 2, where m plus n is zero, 1 or 2.  
 
     
     
       2. A compound as claimed in  claim 1 , wherein, in the formula I, M 1  is Zr or Hf, R 1  and R 2  are identical or different and are methyl or chlorine, R 3  and R 6  are identical or different and are methyl, isopropyl, phenyl, ethyl or trifluoromethyl, R 4  and R 5  are hydrogen or as defined for R 3  and R 6 , or R 4  forms an aliphatic or aromatic ring with R 6 , or adjacent radicals R 4  form an aliphatic or aromatic ring, and  R 7  is a 
                 
 
       radical, and m plus n are zero or 1. 
     
     
       3. A compound as claimed in  claim 1 , wherein the compound of the formula I is Me 2 Si(2,4-dimethyl-1-indenyl) 2 ZrCl 2 , Me 2 Si(2-methyl-4-isopropyl-1-indenyl) 2 ZrCl 2 , Me 2 Si(2-ethyl-4-methyl-1-indenyl) 2 ZrCl 2 , Ph(Me) Si(2-methyl-4-isopropyl-1-indenyl) 2 ZrCl 2 , Me 2 Si(2-methyl-4,5-benzoindenyl) 2 ZrCl 2 ,  selected from the group consisting of Me 2 Si(2,4,6-trimethyl-1-indenyl) 2 ZrCl 2 , Me 2 Si(2-methyl-4,6-diisopropyl-1-indenyl) 2 ZrCl 2 , Me 2 Si(2-methyl-α-acenaphth-indenyl) 2 ZrCl 2 ,  or Me 2 Si(2-methyl-4-phenyl-1-indenyl) 2 ZrCl 2 , ethylene(2,4,6-trimethyl-1-indenyl) 2 ZrCl 2 , ethylene(2-methyl-4,5-benzoindenyl) 2 ZrCl 2 , methylethylene(2-methyl-α-acenaphthindenyl) 2 ZrCl 2  or Ph(Me)Si(2-methyl-α-acenaphthindenyl) 2 ZrCl 2  .