Catalyst composition for preparing multimodal polyolefin resin with remarkable moldability and mechanical properties, and polymerization method using same

1. A catalyst composition for preparing a multimodal polyolefin resin, comprising:

(i) at least one first metallocene compound represented by following Formula 1;

(ii) at least one second metallocene compound represented by following Formula 2; and

(iii) at least one co-catalyst selected from aluminoxane groups represented by following Formulas 3, 4 and 5,

(L 1 )(L 2 )(X 1 )(X 2 )M 1   [Formula 1]

in Formula 1, M 1 is titanium (Ti), zirconium (Zr) or hafnium (Hf); (L 1 ) and (L 2 ) are independently, a cyclopentadienyl group having an alkyl group of 3 to 10 carbon atoms in which at least one tertiary or quaternary carbon is contained; (X 1 ) and (X 2 ) are independently F, Cl, Br, I or a hydrocarbyl group of 1 to 10 carbon atoms,

(L 3 -Q-L 4 )(X 1 )(X 2 )M 2   [Formula 2]

in Formula 2, M 2 is Ti, Zr or Hf; (L 3 ) is a fluorenyl group having two alkyl groups of 4 to 10 carbon atoms in which quaternary carbon is contained; (L 4 ) is a cyclopentadienyl group having at least one alkyl group of 4 to 10 carbon atoms; (Q) is a crosslinking functional group represented by Formula Q 1 R 1 R 2 , Q 1 is carbon atom (C), silicon atom (Si) or germanium atom (Ge), R 1 and R 2 are independently hydrogen or hydrocarbyl group of 1 to 10 carbon atoms; (X 1 ) and (X 2 ) are independently F, Cl, Br, I or hydrocarbyl group of 1 to 10 carbon atoms,

in Formulas 3, 4 and 5, R′ is a hydrocarbyl group, x is an integer of 1 to 70 and y is an integer of 3 to 50,

wherein the amount of the first metallocene compound represented by Formula 1 is 0.25 to 1.50 moles with respect to 1 mole of the second metallocene compound represented by Formula 2.

2. The catalyst composition for preparing a multimodal polyolefin resin according to claim 1 , wherein (L 1 ) and (L 2 ) in Formula 1 each is different to each other, and is a cyclopentadienyl group having an alkyl group of 3 to 10 carbon atoms, which contains at least one tertiary or quaternary carbon, but does not contain aryl group.

3. The catalyst composition for preparing a multimodal polyolefin resin according to claim 1 , wherein (L 1 ) and (L 2 ) in Formula 1 are the same, and may be a cyclopentadienyl group having an alkyl group of 3 to 10 carbon atoms, which contains at least one tertiary or quaternary carbon, but does not contain aryl group.

4. The catalyst composition for preparing a multimodal polyolefin resin according to claim 1 , wherein (L 4 ) in Formula 2 is a cyclopentadienyl group having an alkyl group of 4 to 10 carbon atoms which does not contains an aryl group.

5. The catalyst composition for preparing a multimodal polyolefin resin according to claim 1 , wherein (L 4 ) in Formula 2 is a cyclopentadienyl group having an alkyl group of 4 to 7 carbon atoms which does not contains aryl group.

6. The catalyst composition for preparing a multimodal polyolefin resin according to claim 1 , wherein R 1 and R 2 in Formula 2 are the same to each other and are aryl group of 6 to 10 carbon atoms.

7. The catalyst composition for preparing a multimodal polyolefin resin according to claim 1 , wherein the first metallocene compound represented by the Formula 1 is a compound represented by following Formula 1m,

in formula 1m, R 1 and R 2 are independently hydrogen atom or methyl group, and n 1 and n 2 are independently an integer of 1 to 3.

8. The catalyst composition for preparing a multimodal polyolefin resin according to claim 1 , wherein the first metallocene compound represented by the Formula 1 is a compound represented by following Formula 1n,

in formula 1n, R 1 and R 2 are independently hydrogen atom or methyl group, and n 1 and n 2 are independently an integer of 1 to 3.

9. The catalyst composition for preparing a multimodal polyolefin resin according to claim 1 , wherein the second metallocene compound represented by the Formula 2 is a compound represented by following Formula 2d,

[Formula 2d]

in formula 2d, R 1 , R 2 and R 3 are independently hydrogen atom or methyl group, and n is independently an integer of 1 to 3.

10. The catalyst composition for preparing a multimodal polyolefin resin according to claim 1 , wherein the amount of aluminum of the aluminoxane is 1 to 100,000 moles with respect to 1 mole of sum of the first metallocene compound of Formula 1 and the second metallocene compound of Formula 2.

11. The catalyst composition for preparing a multimodal polyolefin resin according to claim 1 , wherein the first and second metallocene compound and the aluminoxane are supported by an organic or inorganic carrier.

12. The catalyst composition for preparing a multimodal polyolefin resin according to claim 11 , wherein the amount of aluminum in the catalyst composition is 5 to 30 weight part with respect to 100 weight part of the carrier, and the carrier amount of the transition metal compound in the catalyst composition is 0.01 to 2 weight part with respect to 100 weight part of the carrier.

13. A method for polymerizing polyolefin comprising a step of polymerizing olefin monomer in the presence of a catalyst composition comprising (i) at least one first metallocene compound represented by following Formula 1; (ii) at least one second metallocene compound represented by following Formula 2; and (iii) at least one co-catalyst selected from aluminoxane groups represented by following Formulas 3, 4 and 5,

(L 1 )(L 2 )(X 1 )(X 2 )M 1   [Formula 1]

in Formula 1, M 1 is titanium (Ti), zirconium (Zr) or hafnium (Hf); (L 1 ) and (L 2 ) are independently, a cyclopentadienyl group having an alkyl group of 3 to 10 carbon atoms in which at least one tertiary or quaternary carbon is contained; (X 1 ) and (X 2 ) are independently F, Cl, Br, I or a hydrocarbyl group of 1 to 10 carbon atoms,

(L 3 -Q-L 4 )(X 1 )(X 2 )M 2   [Formula 2]

in Formula 2, M 2 is Ti, Zr or Hf; (L 3 ) is a fluorenyl group having two alkyl groups of 4 to 10 carbon atoms in which quaternary carbon is contained; (L 4 ) is a cyclopentadienyl group having at least one alkyl group of 4 to 10 carbon atoms; (Q) is a crosslinking functional group represented by Formula Q 1 R 1 R 2 , Q 1 is carbon atom (C), silicon atom (Si) or germanium atom (Ge), R 1 and R 2 are independently hydrogen or alkyl group of 1 to 10 carbon atoms; (X 1 ) and (X 2 ) are independently F, Cl, Br, I or hydrocarbyl group of 1 to 10 carbon atoms,

in Formulas 3, 4 and 5, R 1 is a hydrocarbyl group, x is an integer of 1 to 70 and y is an integer of 3 to 50, and

wherein the amount of the first metallocene compound represented by Formula 1 is 0.25 to 1.50 moles with respect to 1 mole of the second metallocene compound represented by Formula 2.