Metallocenes and catalysts for olefin-polymerisation

Abstract

A class of metallocenes of formula (I): (ZR 1 m ) n (Cp)(A) r ML p L′ q (I) wherein ZR 1 m ) is a divalent group bridging Cp and A, Cp is a heterocyclic cyclopentadienyl group of formula (II) or (II′), wherein one of X or Y is a single bond, the other being an heteroatom; R 2 and R 3 are hydrogen, halogen or a hydrocarbon radical, optionally containing heteroatoms; R 4 is a halogen or an hydrocarbon radical, optionally containing heteroatoms; the group A is a cyclopentadienyl derivative or is equal to Cp; M is Ti, Zr or Hf; m is 1 or 2; n ranges from 0 to 4; r is 0 or 1; p and q range from 0 to 3; and a ranges from 0 to 4. Moreover, are disclosed catalyst systems containing these metallocenes, useful in the polymerization of olefins.

1 . A metallocene of formula (I):  
       (ZR 1   m ) n (CP)(A)ML p L′ q    (I)  wherein (ZR 1   m ) n  is a divalent group bridging Cp and A, Z being C, Si, Ge, N or P, and the R 1  groups, equal or different from each other, being H or linear or branched, saturated or unsaturated C 1 -C 20  alkyl, C 3 -C 20  cycloalkyl, C 6 -C 20  aryl, C 7 -C 20  alkylaryl or C 7 -C 20  arylalkyl groups;    Cp is a heterocyclic cyclopentadienyl group of formula (II) or (II′):                                                wherein one of X or Y is a single bond, the other being O, S, NR 6  or PR 6 , R 6  being hydrogen, a linear or branched, saturated or unsaturated C 1 -C 20  alkyl, C 3 -C 20  cycloalkyl, C 6 -C 20  aryl, C 1 -C 20  alkylaryl or C 7 -C 20  arylalkyl groups, optionally containing one or more atoms belonging to groups 13-16 of the Periodic Table of the Elements;    R 2  and R 3 , equal or different from each other, are selected from the group consisting of hydrogen, halogen, linear or branched, saturated or unsaturated C 1 -C 20  alkyl, C 3 -C 20  cycloalkyl, C 6 -C 20  aryl, C 6 -C 20  alkylaryl, C 7 -C 20  arylalkyl, —OR 6 , —OCOR 6 , —SR 6 , —NR 6   2  and —PR 6   2 , wherein R 6  has the meaning reported above; or R 2  and R 3  form together a condensed C 5 -C 7  ring, saturated, unsaturated or aromatic, optionally containing one or more atoms belonging to groups 13-16 of the Periodic Table of the Elements;    the substituents R 4 , equal or different from each other, are selected from the group consisting of halogen, linear or branched, saturated or unsaturated C 1 -C 20  alkyl, C 3 -C 20  cycloalkyl, C 6 -C 20  aryl, C 7 -C 20  alkylaryl, C 7 -C 20  arylalkyl, —OR 6 , —OCOR 6 , —SR 6 , —NR 6   2  and —PR 6   2 , wherein R 6  has the meaning reported above, optionally containing one or more atoms belonging to groups 13-16 of the Periodic Table of the Elements;    a is an integer ranging from 0 to 4;    or Cp is a partially hydrogenated derivative of the heterocyclic group of formula (II) or (II′);    A is a substituted or unsubstituted cyclopentadienyl, a group —NR 6 , R 6  having the meaning reported above, or corresponds to (II) or (II′), or to a partially hydrogenated derivative of (II) or (II′);    M is a transition metal belonging to group 3, 4, 5, 6 or to the lanthanide or actinide groups of the Periodic Table of the Elements;    the substituents L, same or different from each other, are monoanionic sigma ligands selected from the group consisting of hydrogen, halogen, —R 6 , —OR 6 , —OCOR 6 , OSO 2 CF 3 , —SR 6 , —NR 6   2  and —PR 6   2 , wherein the groups R 6 , same or different from each other, have the meaning reported above; the substituents L′, same or different from each other, are coordinating molecules;    m is 1 or 2, being 1 when Z is N or P, and being 2 when Z is C, Si or Ge;    n is an integer ranging from 0 to 4; r is 0 or 1;; n is 0 when r is 0;    p and q are integers ranging from 0 to 3, p being equal to the valence of the metal M minus 2 when r=1, and minus 1 when r=0, and p+q being ≦3.    
     
     
         2 . The metallocene according to  claim 1 , characterized by the fact that (ZR 1   m ) n  is selected from the group consisting of CR 1   2 , SiR 1   2 , GeR 1   2 , NR 1 , PR 1  and (CR 1   2 ) 2 , R 1  having the meaning reported in  claim 1 .  
     
     
         3 . The metallocene according to  claim 2 , characterized by the fact that (ZR 1   m ) n  is Si(CH 3 ) 2 , SiPh 2 , CH 2 , (CH 2 ) 2  or C(CH 3 ) 2 .  
     
     
         4 . The metallocene according to  claim 1 , characterized by the fact that Cp corresponds to formula (III):  
       
         
           
           
               
               
           
         
       
       wherein the substituents R 5 , equal or different from each other, are selected from the group consisting of linear or branched, saturated or unsaturated C 1 -C 2  alkyl, C 3 -C 20  cycloalkyl, C 6 -C 20  aryl, C 7 -C 20  alkylaryl, C 7 -C 20  arylalkyl, —OR 6 , —OCOR 6 , —SR 6 , —NR 6   2  and —PR 6   2 , wherein R 6  has the meaning reported above; b is an integer ranging from 0 to 4; X, Y, R 4  and a have the meaning reported in  claim 1 .  
     
     
         5 . The metallocene according to  claim 4 , characterized by the fact that Cp is selected from the group consisting of 5,10-dihydroindeno[1,2-b]indol-10-yl, N-methyl-5,10-dihydroindeno [1,2-b]indol-10-yl, N-phenyl-5,10-dihydroindeno [1,2-b]indol-10-yl, 5,6-dihydroindeno[2,1-b]indol-6-yl, N-methyl-5,6-dihydroindeno[2,1-b]indol-6-yl, N-ally-5,6-dihydroindeno [2,1-b]indol-6-yl and N-phenyl-5,6-dihydroindeno [2,1-b]indol-6-yl.  
     
     
         6 . The metallocene according to  claim 1  or  4 , characterized by the fact that A corresponds to formula (III), as defined in  claim 4 .  
     
     
         7 . The metallocene according to  claim 6 , characterized in being methylen-bis(N-methyl-5,6-dihydroindeno[2,1-b]indol-6-yl)zirconium dichloride or dimethyl.  
     
     
         8 . The metallocene according to  claim 1 , characterized by the fact that A is selected from the group consisting of cyclopentadienyl, 4-t-butyl-cyclopentadienyl, 4-adamantyl-cyclopentadienyl, indenyl and tetrahydroindenyl.  
     
     
         9 . The metallocene according to  claim 1 , characterized by the fact that M is Ti, Zr or Hf.  
     
     
         10 . The metallocene according to  claim 1 , characterized by the fact that L is halogen or R 6 .  
     
     
         11 . A bridged ligand of formula (IV):  
       (ZR 1   m ) n (Cp)(A)   (IV)  wherein (ZR 1   m ) n  is a divalent group bridging Cp and A, Z being C, Si, Ge, N or P, and the R 1  groups, equal or different from each other, being H or linear or branched, saturated or unsaturated C 1 -C 20  alkyl, C 3 -C 20  cycloalkyl, C 6 -C 20  aryl, C 7 -C 20  alkylaryl or C 7 -C 20  arylalkyl groups;    Cp is a heterocyclic cyclopentadienyl group of formula (II) or (II′):                          wherein one of X or Y is a single bond, the other being O, S, NR 6  and PR 6 , R 6 being hydrogen, a linear or branched, saturated or unsaturated C 1 -C 20  alkyl, C 3 -C 20  cycloalkyl, C 6 -C 20  aryl, C 7 -C 20  alkylaryl or C 7 -C 20  arylalkyl groups, optionally containing one or more atoms belonging to groups 13-16 of the Periodic Table of the Elements;    R 2  and R 3 , equal or different from each other, are selected from the group consisting of hydrogen, halogen, linear or branched, saturated or unsaturated C 1 -C 20  alkyl, C 3 -C 20  cycloalkyl, C 6 -C 20  aryl, C 7 -C 20  alkylaryl, C 7 -C 20  arylalkyl, —OR 6 , —OCOR 6 , —SR 6 , —NR 6   2  and —PR 6   2 , wherein R 6  has the meaning reported above; or R 2  and R 3  can form together a condensed C 5 -C 7  ring, saturated, unsaturated or aromatic, optionally containing one or more atoms belonging to groups 13-16 of the Periodic Table of the Elements;    the substituents R 4 , equal or different from each other, are selected from the group consisting of halogen, linear or branched, saturated or unsaturated C 1 -C 20  alkyl, C 3 -C 20  cycloalkyl, C 6 -C 20  aryl, C 7 -C 20  alkylaryl, C 7 -C 20  arylalkyl, —OR 6 , —OCOR 6 , —SR 6 , —NR 6   2  and —PR 6   2 , wherein R 6  has the meaning reported above, optionally containing one or more atoms belonging to groups 13-16 of the Periodic Table of the Elements;    a is an integer ranging from 0 to 4;    Cp can be a partially hydrogenated derivative of the heterocyclic group of formula (II) or (II′);    A is a substituted or unsubstituted cyclopentadienyl, a group —NR 6 , R 6  having the meaning reported above, or corresponds to (II) or (II′), or to a partially hydrogenated derivative of (II) or (II′);    m is 1 or 2, being 1 when Z is N or P, and being 2 when Z is C, Si or Ge; n is an integer ranging from 1 to 4.    
     
     
         12 . The bridged ligand according to  claim 11 , characterized by the fact that (ZR 1   m ) n  is selected from the group consisting of Si(CH 3 ) 2 , SiPh 2 , CH 2 , (CH 2 ) 2  and C(CH 3 ) 2 .  
     
     
         13 . The bridged ligand according to  claim 11 , characterized by the fact that Cp corresponds to formula (III):  
       
         
           
           
               
               
           
         
         wherein the substituents R 5 , equal or different from each other, are selected from the group consisting of halogen, linear or branched, saturated or unsaturated C 1 -C 20  alkyl, C 3 -C 20  cycloalkyl, C 6 -C 20  aryl, C 7 -C 20  alkylaryl, C 7 -C 20  arylalkyl, —OR 6 , —OCOR 6 , —SR 6 , —NR 6   2  and —PR 6   2 , wherein R 6  has the meaning reported in  claim 11;  b is an integer ranging from 0 to 4; X, Y, R 4  and a have the meanings reported in  claim 11 .  
       
     
     
         14 . The bridged ligand according to  claim 13 , characterized by the fact that Cp is selected from the group consisting of N-methyl-5,10-dihydroindeno[1,2-b]indolyl, N-phenyl-5,10-dihydroindeno[1,2-b]indolyl, N-allyl-5,10-dihydroindeno[1,2-b]indole, N-methyl-5,6-dihydroindeno[2,1-b]indole, N-phenyl-5,6-dihydroindeno[2,1-b]indole and N-allyl-5,6-dihydroindeno [2,1-b]indole.  
     
     
         15 . The bridged ligand according to  claim 11 , characterized by the fact that A corresponds to formula (III), as defined in  claim 13 .  
     
     
         16 . The bridged ligand according to  claim 15 , characterized in being 6-[(N-methyl-5,6-dihydroindeno[2,1-b]indol-6-yl)methyl]-N-methyl-5,6-dihydroindeno[2,1-b]indole.  
     
     
         17 . A catalyst for the polymerization of olefins comprising the reaction product between: 
 a metallocene as described in anyone of claims  1 - 10 , optionally as a reaction product with an organo-aluminum compound of formula AlR 7   3  or Al 2 R 7   6 , in which the substituents R 7 , same or different from each other, are selected from the group consisting of halogen, linear or branched, saturated or unsaturated C 1 -C 20  alkyl, C 3 -C 20  cycloalkyl, C 6 -C 20  aryl, C 7 -C 20  alkylaryl, C 7 -C 20  arylalkyl, —OR 6 , —OCOR 6 , —SR 6 , —NR 6   2  and —PR 6   2 , wherein R 6  has the meaning reported in  claim 1;     an alumoxane, optionally in admixture with an organo-aluminum compound of formula AlR 7   3  or Al 2 R 7 , the substituents R 7  having the meanings reported above, or one or more compounds capable of forming an alkyl metallocene cation.    
     
     
         18 . The catalyst according to  claim 17 , characterized by the fact that said alumoxane is obtained by reacting water with an organo-aluminum compound of formula AlR 7   3  or Al 2 R 7   6 , where at least one R 7  is not halogen.  
     
     
         19 . The catalyst according to claims  17  and  18 , characterized by the fact that said alumoxane is MAO, TIBAO and/or TIOAO, and that said organo-aluminum compound is TIOA, TMA and/or TIBA.  
     
     
         20 . A process for the polymerization of olefins comprising the polymerization reaction of at least an olefinic monomer in the presence of a catalyst as claimed in any of  claims 17  to  19 .  
     
     
         21 . The process according to  claim 20 , for the polymerization of propylene.  
     
     
         22 . The process according to  claim 20 , for the preparation of polyethylene or LLDPE copolymers.  
     
     
         23 . The process according to  claim 22 , characterized by the fact that said catalyst comprises the metallocene methylen-bis(N-methyl-5,6-dihydroindeno[2,1-b]indol-6-yl) zirconium dichloride or dimethyl.  
     
     
         24 . The process according to  claim 20 , for the preparation of elastomeric copolymers of ethylene with one or more a-olefins of formula CH 2 ═CHR, wherein R is an alkyl radical having from 1 to 10 carbon atoms, optionally containing small proportions of units deriving from polyene.  
     
     
         25 . The process according to  claim 20 , for the preparation of cycloolefin polymers, optionally containing units deriving from linear olefins.