Ethylene copolymer and a method of preparing the same

Abstract

Provided are ethylene copolymers and a process for preparing the same. More specifically, provided are ethylene copolymers exhibiting excellent processibility and physical properties due to its multimodal molecular weight distribution index, through a multi-stage process by using reactors connected in series or in parallel in the presence of catalyst composition containing transition metal catalyst, and a process for preparing the same.

1 - 19 . (canceled) 
     
     
         20 . Ethylene copolymer prepared by using a process, wherein the process comprises
 (a) polymerizing ethylene and one or more C3-C18 α-olefin comonomer(s) in the presence of a catalyst composition containing a transition metal catalyst represented by Chemical Formula (1) in one or more reactor(s) to produce a first copolymer; and   (b) passing the first copolymer prepared from stage (a) through at least one other reactor(s) containing ethylene or ethylene and at least one C3-C18 α-olefin at a temperature higher than the reaction temperature of stage (a) in the presence of the same catalyst composition employed in stage (a) in order to prepare polymer of high temperature which contains ethylene and C3-C18 α-olefin copolymer composition.   
       
         
           
           
               
               
           
         
         [In the formula, M represents transition metal from Group 4 in the Periodic Table of Elements; 
         Cp represents a cyclopentadienyl ring which is η 5 -linkable to the core metal M, or a fused ring containing a cyclopentadienyl ring, in which the cyclopentadienyl ring or the fused ring containing a cyclopentadienyl ring may be further substituted by one or more substituents 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  and X 2  independently represent 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 
       
       
         
           
           
               
               
           
         
         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 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.] 
     
     
         21 . Ethylene copolymer according to  claim 20 , which comprises 10˜70% by weight of the polymer prepared from stage (a) and 30˜90% by weight of the polymer prepared from stage (b). 
     
     
         22 . Ethylene copolymer according to  claim 21 , wherein the polymer prepared from stage (a) has MI of 0.001 to 2.0 g/10 min and density of 0.860 to 0.925 g/cm 3 , and the polymer prepared from stage (b) has MI of 0.1 to 100.0 g/10 min and density of 0.900 to 0.970 g/cm 3 . 
     
     
         23 . Ethylene copolymer according to  claim 20 , which is linear low density polyethylene copolymer having the density of 0.910 to 0.940 g/cm 3 . 
     
     
         24 . Ethylene copolymer according to  claim 20 , which is very low density ethylene copolymer having the density of 0.900 to 0.910 g/cm 3 . 
     
     
         25 . Ethylene copolymer according to  claim 20 , which has the molecular weight distribution index of 2.8 to 30. 
     
     
         26 . Ethylene copolymer according to  claim 20 , which is used for blown film, casting film, injection molding, blow molding or pipe. 
     
     
         27 . Ethylene copolymer prepared by using a process, wherein the process comprises
 (a) polymerizing ethylene and one or more C3-C18 α-olefin comonomer(s) in the presence of a catalyst composition containing a transition metal catalyst represented by Chemical Formula (1) in one or more reactor(s) to produce a first copolymer;   (b) reacting the ethylene or ethylene and one or more C3-C18 α-olefin at a temperature higher than the reaction temperature of stage (a) in the presence of the same catalyst composition employed in stage (a) in at least one other reactor(s), in order to prepare a second copolymer; and   (c) mixing the first copolymer with the second copolymer.   
       
         
           
           
               
               
           
         
         [In the formula, M represents transition metal from Group 4 in the Periodic Table of Elements; 
         Cp represents a cyclopentadienyl ring which is η 5 -linkable to the core metal M, or a fused ring containing a cyclopentadienyl ring, in which the cyclopentadienyl ring or the fused ring containing a cyclopentadienyl ring may be further substituted by one or more substituents 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  and X 2  independently represent 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 
       
       
         
           
           
               
               
           
         
         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 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.] 
     
     
         28 . Ethylene copolymer according to  claim 27 , which comprises 10˜70% by weight of the polymer prepared from stage (a) and 30˜90% by weight of the polymer prepared from stage (b). 
     
     
         29 . Ethylene copolymer according to  claim 28 , wherein the polymer prepared from stage (a) has MI of 0.001 to 2.0 g/10 min and density of 0.860 to 0.925 g/cm 3 , and the polymer prepared from stage (b) has MI of 0.1 to 100.0 g/10 min and density of 0.900 to 0.970 g/cm 3 . 
     
     
         30 . Ethylene copolymer according to  claim 27 , which is linear low density polyethylene copolymer having the density of 0.910 to 0.940 g/cm 3 . 
     
     
         31 . Ethylene copolymer according to  claim 27 , which is very low density ethylene copolymer having the density of 0.900 to 0.910 g/cm 3 . 
     
     
         32 . Ethylene copolymer according to  claim 27 , which has the molecular weight distribution index of 2.8 to 30. 
     
     
         33 . Ethylene copolymer according to  claim 27 , which is used for blown film, casting film, injection molding, blow molding or pipe.