METHOD FOR PREPARING ELASTOMERIC COPOLYMERS OF ETHYLENE AND a-OLEFINS

Abstract

Provided is a process for preparing copolymers of ethylene with α-olefin. More specifically, provided are transition metal compound being useful as catalyst for preparing those copolymers, a catalyst composition comprising the same, and a process for preparing elastic copolymers of ethylene with α-olefin, having the density of not more than 0.910, which can be adopted to a wide variety of applications including film, electric wires, and hot-melt adhesives. The catalyst composition is a catalytic system which comprises transition metal catalyst comprising a cyclopentadiene derivative and at least one anionic ligand(s) of aryloxy group with an aryl derivative at ortho-position, and boron or aluminum compound as an activator. Provided is a process for copolymerizing ethylene with α-olefin to produce copolymer having narrow molecular weight distribution and uniform density distribution with the density of not more than 0.910, with high activity and excellent reactivity on higher α-olefin.

1 . A copolymers of ethylene with α-olefin, having the density of 0.850˜0.910 by copolymerizing ethylene with (C3-C18) α-olefin in the presence of catalyst composition comprising transition metal compound catalyst represented by Chemical Formula (1) in a single reactor or continuous reactors connected in series or in parallel for 2-stage reaction. 
       
         
           
           
               
               
           
         
         [In Chemical Formula (1), 
         M represents transition metal from Group 4 in the Periodic Table of Elements; 
         Cp represents cyclopentadienyl ring which is η 5 -linkable to the core metal M, or a fused ring containing a cyclopentadienyl ring, and the cyclopentadienyl ring or the fused ring containing a cyclopentadienyl ring may be further substituted by one or more substituent(s) selected from (C1-C20)alkyl, (C6-C30)aryl, (C2-C20)alkenyl and (C6-C30)ar(C1-C20)alkyl; 
         R 1  through R 4  independently represent hydrogen atom, halogen atom, (C1-C20)alkyl, (C3-C20)cycloalkyl, (C6-C30)aryl, (C6-C30)ar(C1-C10)alkyl, (C1-C20)alkoxy, (C3-C20)alkylsiloxy, (C6-C30)arylsiloxy, (C1-C20)alkylamino, (C6-C30)arylamino, (C1-C20)alkylthio, (C6-C30)arylthio or nitro, or each of R 1  through R 4  may be linked to an adjacent substituent via (C3-C12)alkylene or (C3-C12) alkenylene with or without containing a fused ring to form an alicyclic ring, or a monocyclic or polycyclic aromatic ring; 
         Ar 1  represents (C6-C30)aryl or (C3-C30)heteroaryl containing one or more heteroatom(s) selected from N, O and S; 
         X 1  represents halogen atom, (C1-C20)alkyl, (C3-C20)cycloalkyl, (C6-C30)ar(C1-C20)alkyl, (C1-C20)alkoxy, (C3-C20)alkylsiloxy, (C6-C30)arylsiloxy, (C1-C20)alkylamino, (C6-C30)arylamino, (C1-C20)alkylthio, (C6-C30)arylthio, or 
       
       
         
           
           
               
               
           
         
       
       X 2  represents 
       
         
           
           
               
               
           
         
         R 11  through R 15  independently represent hydrogen atom, halogen atom, (C1-C20)alkyl, (C3-C20)cycloalkyl, (C6-C30)aryl, (C6-C30)ar(C1-C10)alkyl, (C1-C20)alkoxy, (C3-C20)alkylsiloxy, (C6-C30)arylsiloxy, (C1-C20)alkylamino, (C6-C30)arylamino, (C1-C20)alkylthio, (C6-C30)arylthio or nitro, or each of R 11  through R 15  may be linked to an adjacent substituent via (C3-C12)alkylene or (C3-C12) alkenylene with or without containing a fused ring to form an alicyclic ring, or a monocyclic or polycyclic aromatic ring; and 
         the alkyl, aryl, cycloalkyl, aralkyl, alkoxy, alkylsiloxy, arylsiloxy, alkylamino, arylamino, alkylthio or arylthio of R 1  through R 4 , R 11  through R 15 , X 1  and X 2 ; the ring formed by linkage of each of R 1  through R 4  or R 11  through R 15  to an adjacent substituent via alkylene or alkenylene; or the aryl or heteroaryl of Ar 1  and Ar 11  may be further substituted by one or more substituent(s) selected from halogen atom, (C1-C20)alkyl, (C3-C20)cycloalkyl, (C6-C30)aryl, (C6-C30)ar(C1-C10)alkyl, (C1-C20)alkoxy, (C3-C20)alkylsiloxy, (C6-C30)arylsiloxy, (C1-C20)alkylamino, (C6-C30)arylamino, (C1-C20)alkylthio, (C6-C30)arylthio, nitro and hydroxyl.] 
       
     
     
         2 . The copolymers of ethylene with α-olefin according to  claim 1 , wherein M is Ti, Zr or Hf in the transition metal catalyst of Chemical Formula (1). 
     
     
         3 . The copolymers of ethylene with α-olefin according to  claim 2 , wherein the transition metal catalyst is selected from those represented by one of Chemical Formulas (1-6) to (1-14): 
       
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         wherein, 
         R 21  through R 26  independently represent hydrogen atom, halogen atom, (C1-C20)alkyl, (C3-C20)cycloalkyl, (C6-C30)aryl, (C6-C30)ar(C1-C10)alkyl, (C1-C20)alkoxy, (C3-C20)alkylsiloxy, (C6-C30)arylsiloxy, (C1-C20)alkylamino, (C6-C30)arylamino, (C1-C20)alkylthio, (C6-C30)arylthio or nitro, or each of R 21  through R 26  may be linked to an adjacent substituent via (C3-C12)alkylene or (C3-C12) alkenylene with or without containing a fused ring to form an alicyclic ring, or a monocyclic or polycyclic aromatic ring; the alkyl, aryl, cycloalkyl, aralkyl, alkoxy, alkylsiloxy, arylsiloxy, alkylamino, arylamino, alkylthio or arylthio of R 21  through R 26  may be further substituted by one or more substituent(s) selected from halogen atom, (C1-C20)alkyl, (C3-C20)cycloalkyl, (C6-C30)aryl, (C6-C30)ar(C1-C10)alkyl, (C1-C20)alkoxy, (C3-C20)alkylsiloxy, (C6-C30)arylsiloxy, (C1-C20)alkylamino, (C6-C30)arylamino, (C1-C20)alkylthio, (C6-C30)arylthio, nitro and hydroxyl; 
         Cp represents a cyclopentadienyl ring which is η 5 -linkable to the core metal M, or a fused ring containing a cyclopentadienyl ring, and the cyclopentadienyl ring or the fused ring containing a cyclopentadienyl ring may be further substituted by one or more substituent(s) selected from (C1-C20)alkyl, (C6-C30)aryl, (C2-C20)alkenyl and (C6-C30)ar(C1-C20)alkyl; and 
         X 1  represents methyl or Cl. 
       
     
     
         4 . The copolymers of ethylene with α-olefin according to  claim 3 , wherein the transition metal catalyst is selected from those represented by one of Chemical Formulas 1-6-1 to 1-14-1: 
       
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         wherein, Cp independently represents cyclopentadienyl ring which is η 5 -linkable to core metal Ti, or a fused ring containing a cyclopentadienyl ring, and the fused ring containing a cyclopentadienyl ring may be further substituted by one or more substituent(s) selected from (C1-C20)alkyl, (C6-C30)aryl, (C2-C20)alkenyl and (C6-C30)ar(C1-C20)alkyl; and 
         X 1  represents methyl or Cl. 
       
     
     
         5 . The copolymers of ethylene with α-olefin according to  claim 1 , wherein the catalyst composition comprises the transition metal catalyst of Chemical Formula (1), and cocatalyst selected from aluminoxane compounds, alkylaluminum compounds, boron compounds and mixtures thereof. 
     
     
         6 . The copolymers of ethylene with α-olefin according to  claim 5 , wherein the ratio of the transition metal catalyst to the cocatalyst is 1:0.5˜50:1-1,000 on the basis of molar ratio of transition metal M:boron atom:aluminum atom. 
     
     
         7 . The copolymers of ethylene with α-olefin according to  claim 5 , wherein the boron compound cocatalyst is selected from N,N-dimethylanilinium tetrakispentafluorophenylborate and triphenylmethylinium tetrakispentafluorophenylborate, and mixtures thereof. 
     
     
         8 . The copolymers of ethylene with α-olefin according to  claim 1 , wherein the α-olefin comonomer is selected from propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene, and mixtures thereof. 
     
     
         9 . The copolymers of ethylene with α-olefin according to  claim 1 , wherein the content of α-olefin comonomer is from 10% by weight to 60% by weight of the copolymer. 
     
     
         10 . The copolymers of ethylene with α-olefin according to  claim 9 , wherein the content of α-olefin comonomer is from 20% by weight to 45% by weight of the copolymer. 
     
     
         11 . The copolymers of ethylene with α-olefin according to  claim 1 , wherein the density of the copolymer is from 0.855 to 0.905 g/cc. 
     
     
         12 . The copolymers of ethylene with α-olefin according to  claim 11 , wherein the density of the copolymer is from 0.860 to 0.900 g/cc. 
     
     
         13 . The copolymers of ethylene with α-olefin according to  claim 1 , wherein the weight average molecular weight is from 30,000 to 500,000, and the molecular weight distribution (Mw/Mn) is from 1.5 to 3.0. 
     
     
         14 . The copolymers of ethylene with α-olefin according to  claim 1 , wherein the pressure in the reactor for the process is from 10 to 150 atm, and the temperature for polymerization is from 80 to 250° C. 
     
     
         15 . (canceled)