The present invention relates to a novel Group 4 transition metal compound, a method for preparing the compound, a catalyst composition comprising the compound, and a method for preparing a polyolefin comprising performing a polymerization reaction of olefin monomers, in the presence of the catalyst composition. Since the Group 4 transition metal compound of the present invention exhibits an excellent catalytic activity in polyolefin synthesis reactions, as well as having excellent thermal stability, it can be used for polyolefin synthesis reactions at high temperatures, and by changing the type of a central metal and ligand, the weight average molecular weight of synthesized polyolefins and the octene content in the polymer can be controlled. Therefore, it can be effectively used in polyolefin synthesis processes in which grades are controlled.

The present invention relates to a novel Group 4 transition metal compound, a method for preparing the compound, a catalyst composition comprising the compound, and a method for preparing a polyolefin comprising performing a polymerization reaction of olefin monomers, in the presence of the catalyst composition. Since the Group 4 transition metal compound of the present invention exhibits an excellent catalytic activity in polyolefin synthesis reactions, as well as having excellent thermal stability, it can be used for polyolefin synthesis reactions at high temperatures, and by changing the type of a central metal and ligand, the weight average molecular weight of synthesized polyolefins and the octene content in the polymer can be controlled. Therefore, it can be effectively used in polyolefin synthesis processes in which grades are controlled.

A production method for a cyclic olefin copolymer which is capable of efficiently producing a cyclic olefin copolymer by copolymerizing monomers including a norbornene monomer and ethylene while suppressing the formation of a polyethylene-like impurity, and a catalyst composition for the copolymerization of a norbornene monomer and ethylene. Monomers including a norbornene monomer and ethylene are polymerized in the presence of a metal-containing catalyst, and the metal-containing catalyst has a structure in which a nitrogen atom is bonded to a transition metal of Group 4 of the periodic table and an atom of Group 15 of the periodic table.

A production method for a cyclic olefin copolymer which is capable of efficiently producing a cyclic olefin copolymer by copolymerizing monomers including a norbornene monomer and ethylene while suppressing the formation of a polyethylene-like impurity, and a catalyst composition for the copolymerization of a norbornene monomer and ethylene. Monomers including a norbornene monomer and ethylene are polymerized in the presence of a metal-containing catalyst, and the metal-containing catalyst has a structure in which a nitrogen atom is bonded to a transition metal of Group 4 of the periodic table and an atom of Group 15 of the periodic table.

Embodiments of a method for producing a multimodal ethylene-based polymer having a first, second, and third ethylene-based component, wherein the multimodal ethylene based polymer results when ethylene monomer, at least one C.sub.3-C.sub.12 comonomer, solvent, and optionally hydrogen pass through a first solution, and subsequently, a second solution polymerization reactor. The first solution polymerization reactor or the second solution polymerization reactor receives both a first catalyst and a second catalyst, and a third catalyst passes through either the first or second solution polymerization reactors where the first and second catalysts are not already present. Each ethylene-based component is a polymerized reaction product of ethylene monomer and C.sub.3-C.sub.12 comonomer catalyzed by one of the three catalysts.

Embodiments of a method of producing a multimodal ethylene-based polymer comprising a first catalyst and a second catalyst in a first solution polymerization reactor and a third catalyst in a second solution polymerization reactor.

The present disclosure provides a novel transition metal compound having excellent structural stability together with polymerization reactivity, and thereby is useful as a catalyst in preparing an olefin-based polymer, particularly, a low density olefin-based polymer, and a catalyst composition including the same.

Provided are a metal-ligand complex, a catalyst composition for ethylene-based polymerization including the same, and a method for preparing an ethylene-based polymer using the same. Since the metal-ligand complex of the present invention in which a certain functional group is introduced to a certain position has high solubility and catalytic activity, the catalyst composition comprising the same for ethylene-based polymerization including the same may produce an ethylene-based polymer having excellent physical properties.

Provided are a metal-ligand complex, a catalyst composition for ethylene-based polymerization including the same, and a method for preparing an ethylene-based polymer using the same. Since the metal-ligand complex of the present invention in which a certain functional group is introduced to a certain position has high solubility and catalytic activity, the catalyst composition comprising the same for ethylene-based polymerization including the same may produce an ethylene-based polymer having excellent physical properties.

This invention relates to novel and improved catalyst and catalysts systems for the oligomerization of the higher olefins, which produce lubricants having improved properties, such as end-saturated oligomer chains which are needless to hydrogenation process, low kinematic viscosity and/or high viscosity index, low pour point, and high flash point lubricants.