WO2024074937A1 - Transition metal compound, catalyst composition containing the same, and method for preparing olefin polymer using the same - Google Patents

Abstract

The present disclosure relates to a novel transition metal compound, a transition metal catalyst composition for preparing an olefin polymer containing the same, and a method for preparing an olefin polymer using the same. The transition metal compound according to an exemplary embodiment may have a significantly improved solubility in a hydrocarbon-based solvent by introducing a carbazole functional group, such that the catalytic activity may be maintained without deterioration during solution polymerization. In addition, transfer, injection, and the like of the catalyst may be easy and more environmentally friendly, such that an olefin polymer may be efficiently prepared.

Description

TRANSITION METAL COMPOUND, CATALYST COMPOSITION CONTAINING THE SAME, AND METHOD FOR PREPARING OLEFIN POLYMER USING THE SAME

The following disclosure relates to a transition metal compound, a catalyst composition containing the same, and a method for preparing an olefin polymer using the same, and more particularly, to a transition metal compound having an improved solubility by introducing a specific functional group, a catalyst composition containing the same, and a method for preparing an olefin polymer using the same.

In the related art, a so-called Ziegler-Natta catalyst system composed of a titanium or vanadium compound as a main catalyst component and an alkylaluminum compound as a cocatalyst component has been generally used to prepare an ethylene-based polymer such as a copolymer of ethylene and α-olefin or a copolymer of ethylene and olefin-diene.

However, the Ziegler-Natta catalyst system exhibits high activity for ethylene polymerization, but has disadvantages in that a molecular weight distribution of the generally produced polymer is broad due to heterogeneous catalytic active sites, and in particular, a uniform composition distribution is not implemented in the copolymer of ethylene and α-olefin.

Subsequently, various studies have been conducted on, as a homogeneous catalyst having homogeneous catalytic active sites, a metallocene catalyst system that may produce polyethylene having a narrow molecular weight distribution and a uniform composition distribution compared to the existing Ziegler-Natta catalyst system and is composed of a metallocene compound of a transition metal of Group 4 in the periodic table, such as zirconium or hafnium, and methylaluminoxane as a cocatalyst.

For example, European Patent Application Publication Nos. 0320762 and 0372632 disclose that polyethylene having a molecular weight distribution (Mw/Mn) of 1.5 to 2.0 may be prepared by polymerizing ethylene with high activity by activating a metallocene compound in Cp₂TiCl₂, Cp₂ZrCl₂, Cp₂ZrMeCl, Cp₂ZrMe₂, ethylene(IndH₄)₂ZrCl₂, or the like with methylaluminoxane as a cocatalyst.

However, it is difficult to obtain a high molecular weight polymer with the above catalyst system. That is, it is known that when a solution polymerization method performed at a high temperature is applied, the polymerization activity is rapidly reduced and a β-dehydrogenation reaction is dominant, which is unsuitable for preparing a high molecular weight polymer.

Meanwhile, since a Cl functional group substituted in the catalyst may cause corrosion or the like depending on a material used in a process, a catalyst substituted with dimethyl has been studied to avoid the problem of corrosion caused by Cl, but this catalyst also has a poor solubility, which makes it difficult to inject the catalyst into the polymerization process. Toluene, xylene, or the like may be used to dissolve a low-solubility catalyst, but when a product that may come into contact with food is produced, the use of the aromatic solvent such as toluene or xylene is problematic.

Accordingly, studies on a competitive catalyst having characteristics such as an excellent solubility, high-temperature activity, reactivity with higher α-olefin, and ability to produce a high molecular weight polymer have been urgently demanded.

An embodiment of the present invention is directed to providing a transition metal compound having an improved solubility not only in a hydrocarbon-based solvent but also in a non-aromatic hydrocarbon-based solvent in order to replace an existing aromatic solvent that may be harmful to the environment and the human body.

Another embodiment of the present invention is directed to providing a method for preparing an olefin polymer using the transition metal compound according to an exemplary embodiment as a catalyst.

In one general aspect, there is provided a transition metal compound represented by the following Chemical Formula 1A:

[Chemical Formula 1A]

in Chemical Formula 1A,

M is a transition metal of Group 4 in the periodic table;

Y's are each independently -O-, -S-, -NR^1aa-, or -PR^2aa-; R^1aa and R^2aa are each independently hydrogen, (C1-C20)hydrocarbylene, (C1-C20)alkoxylene, (C6-C20)aryloxylene, or (C1-C20)alkylsilyl; and the hydrocarbylene, alkoxylene, aryloxylene, and alkylsilyl of Y may be substituted with halogen;

L is a linker with 1 to 50 atoms excluding hydrogen; and

R^1a to R^16a are each independently hydrogen, halogen, (C1-C30)heterohydrocarbyl, (C1-C30)hydrocarbyl, (C1-C30)alkoxy, (C6-C30)aryloxy, (C1-C30)alkylsilyl, (C1-C30)alkylboryl, (C1-C30)alkylamino, (C1-C30)diallylamino, (C1-C30)alkylphosphino, (C1-C30)alkylthio, or (C6-C30)arylthio, or represented by the following Chemical Formula 5A; the heterohydrocarbyl, hydrocarbyl, alkoxy, aryloxy, alkylsilyl, alkylboryl, alkylamino, alkylphosphino, alkylthio, and arylthio of R^1a to R^16a may be substituted with halogen, or adjacent substituents of R^1a to R^16a may be linked to each other to form an alicyclic ring or an aromatic ring; and the alicyclic ring and the aromatic ring may be substituted with one or more selected from the group consisting of (C1-C20)alkyl, (C1-C20)alkoxy, (C1-C20)alkoxy(C1-C20)alkyl, (C6-C20)aryl, (C6-C20)aryl(C1-C20)alkyl, (C1-C20)alkyl(C6-C20)aryl, (C1-C20)alkylsilyl, and (C6-C20)arylsilyl,

[Chemical Formula 5A]

in Chemical Formula 5A,

R^35a to R^42a are each independently hydrogen, (C1-C30)alkyl, (C1-C30)alkylsilyl, (C1-C30)alkoxy, (C3-C30)cycloalkyl, (C6-C30)aryl, (C6-C30)aryl(C1-C30)alkyl, or (C1-C30)alkyl(C6-C30)aryl; and

X's are each independently represented by the following Chemical Formula 2A,

[Chemical Formula 2A]

in Chemical Formula 2A,

R^17a to R^24a are each independently hydrogen, (C1-C30)alkyl, (C2-C30)alkenyl, (C2-C30)alkynyl, (C1-C30)alkylsilyl, (C1-C30)alkoxy, (C3-C30)cycloalkyl, (C6-C30)aryl, (C6-C30)aryl(C1-C30)alkyl, or (C1-C30)alkyl(C6-C30)aryl; the alkyl, alkylsilyl, alkoxy, cycloalkyl, aryl, arylalkyl, and alkylaryl of R^17a to R^24a may be substituted with one or more selected from the group consisting of halogen, (C1-C10)alkyl, (C1-C10)alkylamino, (C1-C10)alkoxy, and (C1-C10)alkylsilyl; or adjacent substituents of R^17a to R^24a may be linked to (C3-C12)alkylene or (C3-C12)alkenylene with or without a fused ring to form an alicyclic ring or an aromatic ring; and the alicyclic ring or the aromatic ring may be substituted with one or more selected from the group consisting of (C1-C20)alkyl, (C1-C20)alkoxy, (C1-C20)alkoxy(C1-C20)alkyl, (C6-C20)aryl, (C6-C20)aryl(C1-C20)alkyl, (C1-C20)alkyl(C6-C20)aryl, (C1-C20)alkylsilyl, and (C6-C20)arylsilyl.

In another general aspect, a transition metal catalyst composition for preparing an olefin polymer contains the transition metal compound according to an exemplary embodiment and a cocatalyst.

In still another general aspect, a method for preparing an olefin polymer includes subjecting an olefin monomer to solution polymerization in the presence of the transition metal compound according to an exemplary embodiment, a cocatalyst, and a hydrocarbon-based solvent to obtain an olefin polymer.

Other features and aspects will be apparent from the following detailed description, the drawings, and the claims.

the present disclosure relates to a novel transition metal compound, a transition metal catalyst composition for preparing an olefin polymer containing the same, and a method for preparing an olefin polymer using the same. The transition metal compound according to an exemplary embodiment may have a significantly improved solubility in a hydrocarbon-based solvent by introducing a carbazole functional group, such that the catalytic activity may be maintained without deterioration during solution polymerization. In addition, the transition metal compound according to an exemplary embodiment may efficiently improve the polymerization process and may be significantly advantageous for commercialization because injection, transfer, and the like of the transition metal compound are easy during a solution process.

Further, since the transition metal compound according to an exemplary embodiment has excellent reactivity with an olefin monomer due to an excellent solubility in a hydrocarbon-based solvent, when the transition metal compound according to an exemplary embodiment is used as a catalyst, olefin polymerization may be significantly efficiently performed, and therefore, an olefin polymer may be prepared with a high yield using the same.

Further, in the method for preparing an olefin polymer according to an exemplary embodiment, a transition metal compound having an excellent solubility in a hydrocarbon-based solvent is used as a main catalyst, such that transfer, injection, and the like of the catalyst may be easy and more environmentally friendly, which may enable an olefin polymer to be efficiently prepared.

Exemplary embodiments described in the present specification may be modified into many different forms and the technology according to one exemplary embodiment is not limited to the exemplary embodiments described below. Furthermore, in the entire specification, unless explicitly described otherwise, "comprising", "including", "containing", or "having" any components will be understood to imply the inclusion of other components rather than the exclusion of any other components, and does not exclude elements, materials, or processes which are not further listed.

A numerical range used in the present specification includes upper and lower limits and all values within these limits, increments logically derived from a form and span of a defined range, all double limited values, and all possible combinations of the upper and lower limits in the numerical range defined in different forms. As an example, when a content of a composition is limited to 10% to 80% or 20% to 50%, a numerical range of 10% to 50% or 50% to 80% should also be interpreted as described in the present specification. Unless otherwise specifically defined in the present specification, values out of the numerical range that may occur due to experimental errors or rounded values also fall within the defined numerical range.

Hereinafter, in the present specification, unless otherwise specifically defined, "about" may be considered a value within 30%, 25%, 20%, 15%, 10%, or 5% of a stated value.

Hereinafter, in the present specification, unless otherwise specifically defined, singular forms may be considered to also include plural forms.

The terms "substituent", "radical", "group", "moiety", and "fragment" described in the present specification may be used interchangeably.

The term "alkyl" described in the present specification refers to a saturated linear or branched non-cyclic hydrocarbon having 1 to 30 carbon atoms when the number of carbon atoms is not particularly limited. Representative saturated linear alkyl includes methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, and n-decyl; while representative saturated branched alkyl includes isopropyl, sec-butyl, isobutyl, tert-butyl, isopentyl, 2-methylbutyl, 3-methylbutyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl, 3-methylhexyl, 4-methylhexyl, 5-methylhexyl, 2,3-dimethylbutyl, 2,3-dimethylpentyl, 2,4-dimethylpentyl, 2,3-dimethylhexyl, 2,4-dimethylhexyl, 2,5-dimethylhexyl, 2,2-dimethylpentyl, 2,2-dimethylhexyl, 3,3-dimethylpentyl, 3,3-dimethylhexyl, 4,4-dimethylhexyl, 2-ethylpentyl, 3-ethylpentyl, 2-ethylhexyl, 3-ethylhexyl, 4-ethylhexyl, 2-methyl-2-ethylpentyl, 2-methyl-3-ethylpentyl, 2-methyl-4-ethylpentyl, 2-methyl-2-ethylhexyl, 2-methyl-3-ethylhexyl, 2-methyl-4-ethylhexyl, 2,2-diethylpentyl, 3,3-diethylhexyl, 2,2-diethylhexyl, and 3,3-diethylhexyl.

The term "alkenyl" described in the present specification refers to a linear or branched carbon chain radical containing one or more carbon unsaturated bonds (double bonds), and the term "alkynyl" refers to a linear or branched carbon chain radical containing one or more carbon unsaturated bonds (triple bonds).

The term "alkoxy" described in the present specification refers to -O-(alkyl) including -OCH₃, -OCH₂CH₃, -O(CH₂)₂CH₃, -O(CH₂)₃CH₃, -O(CH₂)₄CH₃, -O(CH₂)₅CH₃, and the like, where the "alkyl" is as defined above.

The terms "alkylene" and "alkenylene" described in the present specification refer to divalent organic radicals derived by removing one hydrogen from "alkyl" and "alkenyl", respectively, and follow the respective definitions of the alkyl and alkenyl described above.

The term "cycloalkyl" described in the present specification refers to a monocyclic or polycyclic saturated ring containing carbon and hydrogen atoms and no carbon-carbon multiple bond. Examples of a cycloalkyl group include, but are not limited to, (C3-C10)cycloalkyl, for example, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and cycloheptyl. The cycloalkyl group may be optionally substituted. In an exemplary embodiment, the cycloalkyl group is a monocyclic or bicyclic ring.

The term "heterohydrocarbyl" described in the present specification may refer to a hydrocarbyl containing one or more heteroatoms of one or more of N, O, and S.

The term "aryl" described in the present specification refers to an organic radical derived from an aromatic hydrocarbon by removal of one hydrogen, includes a monocyclic or fused ring system having suitably 4 to 7 ring atoms or 5 or 6 ring atoms in each ring, and even includes a form in which a plurality of aryls are linked by a single bond. The fused ring system may include an aliphatic ring such as a saturated or partially saturated ring, and necessarily includes at least one aromatic ring. In addition, the aliphatic ring may include nitrogen, oxygen, sulfur, carbonyl, and the like, in a ring. Specific examples of the aryl radical include, but are not limited to, phenyl, naphthyl, biphenyl, indenyl, fluorenyl, phenanthrenyl, anthracenyl, triphenylenyl, pyrenyl, chrysenyl, naphthacenyl, and 9,10-dihydroanthracenyl.

The term "aryloxy" described in the present specification refers to an -O-aryl radical, where the "aryl" is as defined above.

Specific examples of the terms "alkylsilyl" and "arylsilyl" described in the present specification include, but are not limited to, trimethylsilyl, triethylsilyl, t-butyldimethylsilyl, vinyldimethylsilyl, propyldimethylsilyl, triphenylsilyl, diphenylsilyl, and phenylsilyl.

The terms "alkylsiloxy" and "arylsiloxy" described in the present specification refer to an -O-alkylsilyl radical and an -O-arylsilyl radical, respectively, where the "alkyl" and "aryl" are as defined above.

Unless otherwise specified, the term "carbazole" described in the present specification is used to include a case in which the carbon position of carbazole is substituted with a substituent in a range that may be easily derived by those skilled in the art disclosed in the present specification.

The term "substituted" used in the present specification means that a hydrogen atom of a moiety, for example, alkyl, aryl, heteroaryl, heterocycle, or cycloalkyl, to be substituted is substituted with a substituent. In an exemplary embodiment, each carbon atom of a group to be substituted is substituted with no more than two substituents. In another exemplary embodiment, each carbon atom of the group to be substituted is substituted with no more than one substituent. In the case of a keto substituent, two hydrogen atoms are substituted with oxygen attached to carbon by a double bond. Unless otherwise specified, the substituent includes cases of substitution with one or more selected from halogen, hydroxyl, lower alkyl, haloalkyl, mono- or di-alkylamino, (C1-C30)alkyl, (C1-C30)alkoxy, (C3-C30)cycloalkyl, (C6-C30)aryl, (C6-C30)aryl(C1-C30)alkyl, (C1-C30)alkyl(C6-C30)aryl, (C1-C30)alkylsilyl, (C6-C30)arylsilyl, (C6-C30)aryloxy, (C3-C30)alkylsiloxy, (C6-C30)arylsiloxy, (C1-C30)alkylamino, (C6-C30)arylamino, (C1-C30)alkylthio, (C6-C30)arylthio, (C1-C30)alkylphosphine, and (C6-C30)arylphosphine.

The term "olefin polymer" described in the present specification refers to a polymer prepared using an olefin in a range recognizable to those skilled in the art disclosed in the present specification. Specifically, the olefin polymer includes both an olefin homopolymer and a copolymer of olefins, and refers to an olefin homopolymer or a copolymer of olefin and α-olefin.

An exemplary embodiment provides a transition metal compound into which a carbazole substituent is introduced, which has an improved solubility and excellent thermal stability and may be efficiently used in an olefin polymer, the transition metal compound being represented by the following Chemical Formula 1A:

[Chemical Formula 1A]

in Chemical Formula 1A,

M is a transition metal of Group 4 in the periodic table;

Y's are each independently -O-, -S-, -NR^1aa-, or -PR^2aa-; R^1aa and R^2aa are each independently hydrogen, (C1-C20)hydrocarbylene, (C1-C20)alkoxylene, (C6-C20)aryloxylene, or (C1-C20)alkylsilyl; and the hydrocarbylene, alkoxylene, aryloxylene, and alkylsilyl of Y may be substituted with halogen;

L is a linker with 1 to 50 atoms excluding hydrogen; and

R^1a to R^16a are each independently hydrogen, halogen, (C1-C30)heterohydrocarbyl, (C1-C30)hydrocarbyl, (C1-C30)alkoxy, (C6-C30)aryloxy, (C1-C30)alkylsilyl, (C1-C30)alkylboryl, (C1-C30)alkylamino, (C1-C30)diallylamino, (C1-C30)alkylphosphino, (C1-C30)alkylthio, or (C6-C30)arylthio, or represented by the following Chemical Formula 5A; the heterohydrocarbyl, hydrocarbyl, alkoxy, aryloxy, alkylsilyl, alkylboryl, alkylamino, alkylphosphino, alkylthio, and arylthio of R^1a to R^16a may be substituted with halogen, or adjacent substituents of R^1a to R^16a may be linked to each other to form an alicyclic ring or an aromatic ring; and the alicyclic ring and the aromatic ring may be substituted with one or more selected from the group consisting of (C1-C20)alkyl, (C1-C20)alkoxy, (C1-C20)alkoxy(C1-C20)alkyl, (C6-C20)aryl, (C6-C20)aryl(C1-C20)alkyl, (C1-C20)alkyl(C6-C20)aryl, (C1-C20)alkylsilyl, and (C6-C20)arylsilyl,

[Chemical Formula 5A]

in Chemical Formula 5A,

R^35a to R^42a are each independently hydrogen, (C1-C30)alkyl, (C1-C30)alkylsilyl, (C1-C30)alkoxy, (C3-C30)cycloalkyl, (C6-C30)aryl, (C6-C30)aryl(C1-C30)alkyl, or (C1-C30)alkyl(C6-C30)aryl; and

X's are each independently represented by the following Chemical Formula 2A,

[Chemical Formula 2A]

in Chemical Formula 2A,

R^17a to R^24a are each independently hydrogen, (C1-C30)alkyl, (C2-C30)alkenyl, (C2-C30)alkynyl, (C1-C30)alkylsilyl, (C1-C30)alkoxy, (C3-C30)cycloalkyl, (C6-C30)aryl, (C6-C30)aryl(C1-C30)alkyl, or (C1-C30)alkyl(C6-C30)aryl; the alkyl, alkylsilyl, alkoxy, cycloalkyl, aryl, arylalkyl, and alkylaryl of R^17a to R^24a may be substituted with one or more selected from the group consisting of halogen, (C1-C10)alkyl, (C1-C10)alkylamino, (C1-C10)alkoxy, and (C1-C10)alkylsilyl; or adjacent substituents of R^17a to R^24a may be linked to (C3-C12)alkylene or (C3-C12)alkenylene with or without a fused ring to form an alicyclic ring or an aromatic ring; and the alicyclic ring or the aromatic ring may be substituted with one or more selected from the group consisting of (C1-C20)alkyl, (C1-C20)alkoxy, (C1-C20)alkoxy(C1-C20)alkyl, (C6-C20)aryl, (C6-C20)aryl(C1-C20)alkyl, (C1-C20)alkyl(C6-C20)aryl, (C1-C20)alkylsilyl, and (C6-C20)arylsilyl.

The transition metal compound according to an exemplary embodiment has a significantly improved solubility in a hydrocarbon-based solvent and significantly increased catalytic activity by introducing a carbazole group represented by Chemical Formula 2A into the X position of Chemical Formula 1A. Therefore, it is possible to prepare an olefin polymer in a simple and environmentally friendly process using the transition metal compound according to an exemplary embodiment. In particular, the transition metal compound according to an exemplary embodiment is useful in that it may replace an existing aromatic solvent that may be harmful to the environment and the human body because it has a high solubility even in a non-aromatic hydrocarbon-based solvent.

In addition, an olefin polymer may be easily prepared through a solution process using the transition metal compound according to an exemplary embodiment.

In an exemplary embodiment, Y's may be each independently -O-, -S-, -NR^1aa-, or -PR^2aa-, and R^1aa and R^2aa may be each independently any one selected from the group consisting of hydrogen, (C1-C8)hydrocarbylene, (C1-C6)hydrocarbylene, (C1-C5)hydrocarbylene, (C1-C4)hydrocarbylene, (C2-C6)hydrocarbylene, (C1-C10)alkylene, (C1-C8)alkylene, (C1-C6)alkylene, (C1-C5)alkylene, (C1-C4)alkylene, (C2-C6)alkylene, (C1-C8)alkoxylene, (C1-C6)alkoxylene, (C1-C5)alkoxylene, (C1-C4)alkoxylene, (C2-C6)alkoxylene, (C6-C9)aryloxylene, (C6-C8)aryloxylene, (C1-C8)alkylsilyl, (C1-C6)alkylsilyl, (C1-C5)alkylsilyl, (C1-C4)alkylsilyl, and (C2-C6)alkylsilyl. Alternatively, in an exemplary embodiment, the hydrocarbylene, alkylene, alkoxylene, aryloxylene, and alkylsilyl of R^1aa and R^2aa may be substituted with halogen. In -O-, -S-, -NR^1aa-, and -PR^2aa- of Y, "-" may indicate a bond with an adjacent phenylene group and the linker (L).

In an exemplary embodiment, the bond of Y and M may be a covalent bond or a coordinate bond.

In an exemplary embodiment, Y's may be different from each other, for example, Y linked to the linker may contain a nitrogen atom, and Y not linked to the linker may contain an oxygen atom.

In an exemplary embodiment, L may have 1 to 30, 1 to 20, 1 to 10, 1 to 8, or 1 to 5 atoms excluding hydrogen, or may be (C1-C8)alkylene, (C1-C6)alkylene, (C1-C5)alkylene, (C1-C3)alkylene, or (C2-C5)alkylene.

In an exemplary embodiment, R^1a to R^16a may be each independently hydrogen, (C1-C20)heterohydrocarbyl, (C1-C15)heterohydrocarbyl, (C1-C10)heterohydrocarbyl, (C1-C8)heterohydrocarbyl, (C1-C6)heterohydrocarbyl, (C1-C5)heterohydrocarbyl, (C1-C3)heterohydrocarbyl, (C1-C20)hydrocarbyl, (C1-C15)hydrocarbyl, (C1-C10)hydrocarbyl, (C1-C8)hydrocarbyl, (C1-C6)hydrocarbyl, (C1-C5)hydrocarbyl, (C1-C3)hydrocarbyl, (C1-C20)alkyl, (C1-C15)alkyl, (C1-C10)alkyl, (C1-C8)alkyl, (C1-C6)alkyl, (C1-C5)alkyl, (C1-C3)alkyl, -CH₃, (C1-C20)alkoxy, (C1-C15)alkoxy, (C1-C10)alkoxy, (C1-C8)alkoxy, (C1-C6)alkoxy, (C1-C5)alkoxy, (C1-C3)alkoxy, -OCH₃, (C6-C20)aryloxy, (C6-C15)aryloxy, (C6-C10)aryloxy, (C6-C9)aryloxy, or (C6-C8)aryloxy, and the heterohydrocarbyl, hydrocarbyl, alkyl, alkoxy, and aryloxy of R^1a to R^16a may be substituted with halogen, or adjacent substituents of R^1a to R^16a may be linked to each other to form a monocyclic or polycyclic alicyclic ring or aromatic ring.

In an exemplary embodiment, R^1a to R^16a may be represented by Chemical Formula 5A, and in Chemical Formula 5A, R^35a to R^42a may be each independently hydrogen, (C1-C20)alkyl, (C1-C20)alkylsilyl, (C1-C20)alkoxy, (C3-C20)cycloalkyl, (C6-C20)aryl, (C6-C20)aryl(C1-C20)alkyl, or (C1-C20)alkyl(C6-C20)aryl. Alternatively, R^35a to R^42a may be each independently hydrogen, (C1-C20)alkyl, (C1-C15)alkyl, (C1-C10)alkyl, (C1-C8)alkyl, (C1-C6)alkyl, (C1-C5)alkyl, (C2-C6)alkyl, tert-butyl, (C1-C20)alkylsilyl, (C1-C15)alkylsilyl, (C1-C10)alkylsilyl, (C1-C8)alkylsilyl, (C1-C6)alkylsilyl, (C1-C5)alkylsilyl, (C2-C6)alkylsilyl, (C1-C20)alkoxy, (C1-C15)alkoxy, (C1-C10)alkoxy, (C1-C8)alkoxy, (C1-C6)alkoxy, (C1-C5)alkoxy, (C3-C20)cycloalkyl, (C3-C15)cycloalkyl, (C3-C10)cycloalkyl, (C3-C8)cycloalkyl, (C3-C6)cycloalkyl, (C6-C20)aryl, (C6-C15)aryl, (C6-C10)aryl, (C6-C8)aryl, (C6-C20)aryl(C1-C20)alkyl, (C6-C10)aryl(C1-C15)alkyl, (C6-C10)aryl(C1-C10)alkyl, (C6-C10)aryl(C1-C8)alkyl, (C6-C10)aryl(C1-C6)alkyl, (C6-C10)aryl(C1-C5)alkyl, (C6-C10)aryl(C2-C6)alkyl, (C1-C20)alkyl(C6-C20)aryl, (C1-C10)alkyl(C6-C20)aryl, (C1-C10)alkyl(C6-C15)aryl, (C1-C10)alkyl(C6-C10)aryl, or (C1-C10)alkyl(C6-C8)aryl.

In an exemplary embodiment, R^1a to R^16a may be (C1-C20)heterohydrocarbyl, and the (C1-C20)heterohydrocarbyl may contain one or more heteroatoms of one or more of N, O, and S. Accordingly, R^1a to R^16a may have 1 to 20 carbon atoms, but the total number of atoms thereof may exceed 20. As a specific example, R^1a to R^16a may be carbazole substituted with one or more tert-butyl groups, and the tert-butyl group may be substituted on one or more carbon atoms at carbon positions 1 to 8 of carbazole, for example, may be substituted at carbon positions 3 and 6 or carbon positions 2 and 7.

In an exemplary embodiment, R^17a to R^24a may be each independently hydrogen, (C1-C20)alkyl, (C2-C20)alkenyl, (C2-C20)alkynyl, (C1-C20)alkylsilyl, (C1-C20)alkoxy, (C3-C20)cycloalkyl, (C6-C20)aryl, (C6-C20)aryl(C1-C20)alkyl, or (C1-C20)alkyl(C6-C20)aryl; the alkyl, alkylsilyl, alkoxy, cycloalkyl, aryl, arylalkyl, and alkylaryl of R^17a to R^24a may be substituted with one or more selected from the group consisting of halogen, (C1-C10)alkyl, (C1-C10)alkylamino, (C1-C10)alkoxy, and (C1-C10)alkylsilyl; or adjacent substituents of R^17a to R^24a may be linked to (C3-C12)alkylene or (C3-C12)alkenylene with or without a fused ring to form an alicyclic ring or an aromatic ring; and the alicyclic ring or the aromatic ring may be substituted with one or more selected from the group consisting of (C1-C20)alkyl, (C1-C20)alkoxy, (C1-C20)alkoxy(C1-C20)alkyl, (C6-C20)aryl, (C6-C20)aryl(C1-C20)alkyl, (C1-C20)alkyl(C6-C20)aryl, (C1-C20)alkylsilyl, and (C6-C20)arylsilyl.

Alternatively, in an exemplary embodiment, R^17a to R^24a may be each independently hydrogen, (C1-C20)alkyl, (C1-C15)alkyl, (C1-C10)alkyl, (C1-C8)alkyl, (C1-C6)alkyl, (C1-C5)alkyl, (C2-C8)alkyl, tert-butyl, (C2-C20)alkenyl, (C2-C15)alkenyl, (C2-C10)alkenyl, (C2-C8)alkenyl, (C2-C20)alkynyl, (C2-C15)alkynyl, (C2-C10)alkynyl, (C2-C8)alkynyl, (C1-C20)alkylsilyl, (C1-C15)alkylsilyl, (C1-C10)alkylsilyl, (C1-C8)alkylsilyl, (C1-C6)alkylsilyl, (C1-C5)alkylsilyl, (C2-C6)alkylsilyl, (C1-C20)alkoxy, (C1-C15)alkoxy, (C1-C10)alkoxy, (C1-C8)alkoxy, (C1-C6)alkoxy, (C1-C5)alkoxy, (C3-C20)cycloalkyl, (C3-C15)cycloalkyl, (C3-C10)cycloalkyl, (C3-C8)cycloalkyl, (C3-C6)cycloalkyl, (C6-C20)aryl, (C6-C15)aryl, (C6-C10)aryl, (C6-C8)aryl, (C6-C20)aryl(C1-C20)alkyl, (C6-C10)aryl(C1-C15)alkyl, (C6-C10)aryl(C1-C10)alkyl, (C6-C10)aryl(C1-C8)alkyl, (C6-C10)aryl(C1-C6)alkyl, (C6-C10)aryl(C1-C5)alkyl, (C6-C10)aryl(C2-C6)alkyl, (C1-C20)alkyl(C6-C20)aryl, (C1-C10)alkyl(C6-C20)aryl, (C1-C10)alkyl(C6-C15)aryl, (C1-C10)alkyl(C6-C10)aryl, or (C1-C10)alkyl(C6-C8)aryl, and the alkyl, alkylsilyl, alkoxy, cycloalkyl, aryl, arylalkyl, and alkylaryl of R^17a to R^24a may be substituted with one or more selected from the group consisting of halogen, (C1-C10)alkyl, (C1-C8)alkyl, (C1-C6)alkyl, (C1-C5)alkyl, (C1-C10)alkylamino, (C1-C8)alkylamino, (C1-C6)alkylamino, (C1-C5)alkylamino, (C1-C10)alkoxy, (C1-C8)alkoxy, (C1-C6)alkoxy, (C1-C5)alkoxy, (C1-C10)alkylsilyl, (C1-C8)alkylsilyl, (C1-C6)alkylsilyl, and (C1-C5)alkylsilyl. Alternatively, adjacent substituents of R^17a to R^24a may be linked to (C3-C12)alkylene, (C3-C10)alkylene, (C3-C8)alkylene, (C3-C6)alkylene, (C3-C5)alkylene, (C3-C4)alkylene, (C3-C12)alkenylene, (C3-C10)alkenylene, (C3-C8)alkenylene, (C3-C6)alkenylene, (C3-C5)alkenylene, or (C3-C4)alkenylene with or without a fused ring to form an alicyclic ring or an aromatic ring; and the alicyclic ring or the aromatic ring may be substituted with one or more selected from the group consisting of (C1-C20)alkyl, (C1-C15)alkyl, (C1-C10)alkyl, (C1-C8)alkyl, (C1-C6)alkyl, (C1-C5)alkyl, (C1-C20)alkoxy, (C1-C15)alkoxy, (C1-C10)alkoxy, (C1-C8)alkoxy, (C1-C6)alkoxy, (C1-C5)alkoxy, (C1-C20)alkoxy(C1-C20)alkyl, (C1-C10)alkoxy(C1-C20)alkyl, (C1-C10)alkoxy(C1-C15)alkyl, (C1-C10)alkoxy(C1-C10)alkyl, (C1-C10)alkoxy(C1-C8)alkyl, (C1-C10)alkoxy(C1-C6)alkyl, (C1-C10)alkoxy(C1-C5)alkyl, (C6-C20)aryl, (C6-C15)aryl, (C6-C10)aryl, (C6-C8)aryl, (C6-C20)aryl(C1-C20)alkyl, (C6-C10)aryl(C1-C15)alkyl, (C6-C10)aryl(C1-C10)alkyl, (C6-C10)aryl(C1-C8)alkyl, (C6-C10)aryl(C1-C6)alkyl, (C6-C10)aryl(C1-C5)alkyl, (C1-C20)alkyl(C6-C20)aryl, (C1-C10)alkyl(C6-C15)aryl, (C1-C10)alkyl(C6-C10)aryl, (C1-C10)alkyl(C6-C8)aryl, (C1-C20)alkylsilyl, (C1-C15)alkylsilyl, (C1-C10)alkylsilyl, (C1-C8)alkylsilyl, (C1-C6)alkylsilyl, (C1-C5)alkylsilyl, (C6-C20)arylsilyl, (C1-C15)arylsilyl, (C1-C10)arylsilyl, (C1-C8)arylsilyl, (C1-C6)arylsilyl, and (C1-C5)arylsilyl.

Specifically, in an exemplary embodiment, R^17a, R^18a, R^20a, R^21a, R^23a, and R^24a may be hydrogen, and R^19a and R^22a may be a tert-butyl group, a linear or branched C8 alkyl group or C12 alkyl group, or a linear or branched C8 alkenyl group.

In an exemplary embodiment, the transition metal compound may be a compound represented by the following Chemical Formula 1B:

[Chemical Formula 1B]

in Chemical Formula 1B,

M is a transition metal of Group 4 in the periodic table;

R^1b to R^4b are each independently hydrogen, (C1-C20)alkyl, (C6-C20)aryl, or (C6-C20)aryl(C1-C20)alkyl;

R^5b and R^6b are each independently hydrogen or (C1-C20)alkyl;

R^7b and R^8b are each independently hydrogen, halogen, or (C1-C20)alkyl;

a, b, c, d, e, f, g, and h are each independently an integer of 0 to 4; and

m is an integer of 2 to 10.

In an exemplary embodiment, M may be Ti, Zr, or Hf.

In an exemplary embodiment, R^1b to R^4b may be each independently hydrogen, (C1-C15)alkyl, (C1-C10)alkyl, (C1-C8)alkyl, (C1-C6)alkyl, (C1-C5)alkyl, (C1-C4)alkyl, (C2-C6)alkyl, tert-butyl, (C6-C15)aryl, (C6-C10)aryl, (C6-C9)aryl, (C6-C8)aryl, (C6-C10)aryl(C1-C15)alkyl, (C6-C10)aryl(C1-C10)alkyl, (C6-C10)aryl(C1-C8)alkyl, (C6-C10)aryl(C1-C6)alkyl, (C6-C10)aryl(C1-C5)alkyl, (C6-C10)aryl(C1-C4)alkyl, or (C6-C10)aryl(C2-C6)alkyl.

In an exemplary embodiment, R^5b and R^6b may be each independently hydrogen, (C1-C15)alkyl, (C1-C10)alkyl, (C1-C8)alkyl, (C1-C6)alkyl, (C1-C5)alkyl, (C1-C4)alkyl, (C1-C3)alkyl, or -CH₃.

In an exemplary embodiment, R^7b and R^8b may be each independently hydrogen, -I, -Br, -Cl, -F, (C1-C15)alkyl, (C1-C10)alkyl, (C1-C8)alkyl, (C1-C6)alkyl, (C1-C5)alkyl, (C1-C4)alkyl, (C1-C3)alkyl, or -CH₃.

In an exemplary embodiment, a, b, c, d, e, f, g, and h may be each independently an integer of 0 to 3, 1, 2, or 3.

In an exemplary embodiment, m may be an integer of 2 to 8, an integer of 2 to 6, an integer of 2 to 5, or 3.

In an exemplary embodiment, the transition metal compound may be a compound represented by the following Chemical Formula 1C:

[Chemical Formula 1C]

in Chemical Formula 1C,

M is a transition metal of Group 4 in the periodic table;

R^1c to R^8c are each independently hydrogen, (C1-C20)alkyl, (C6-C20)aryl, or (C6-C20)aryl(C1-C20)alkyl;

R^9c and R^10c are each independently (C1-C20)alkyl;

R^11c and R^13c are each independently halogen or (C1-C20)alkyl;

R^12c and R^14c are each independently hydrogen or (C1-C20)alkyl;

i and j are each independently an integer of 0 to 3; and

m is an integer of 2 to 10.

In an exemplary embodiment, M may be Ti, Zr, or Hf.

In an exemplary embodiment, R^1c to R^8c may be each independently hydrogen, (C1-C15)alkyl, (C1-C10)alkyl, (C1-C8)alkyl, (C1-C6)alkyl, (C1-C5)alkyl, (C1-C4)alkyl, (C2-C6)alkyl, tert-butyl, (C6-C15)aryl, (C6-C10)aryl, (C6-C9)aryl, (C6-C8)aryl, (C6-C10)aryl(C1-C15)alkyl, (C6-C10)aryl(C1-C10)alkyl, (C6-C10)aryl(C1-C8)alkyl, (C6-C10)aryl(C1-C6)alkyl, (C6-C10)aryl(C1-C5)alkyl, (C6-C10)aryl(C1-C4)alkyl, or (C6-C10)aryl(C2-C6)alkyl.

In an exemplary embodiment, R^9c and R^10c may be each independently (C1-C15)alkyl, (C1-C10)alkyl, (C1-C8)alkyl, (C1-C6)alkyl, (C1-C5)alkyl, (C1-C4)alkyl, (C1-C3)alkyl, or -CH₃.

In an exemplary embodiment, R^11c and R^13c may be each independently -I, -Br, -Cl, -F, (C1-C15)alkyl, (C1-C10)alkyl, (C1-C8)alkyl, (C1-C6)alkyl, (C1-C5)alkyl, (C1-C4)alkyl, (C1-C3)alkyl, or -CH₃.

In an exemplary embodiment, R^12c and R^14c may be each independently hydrogen, (C1-C15)alkyl, (C1-C10)alkyl, (C1-C8)alkyl, (C1-C6)alkyl, (C1-C5)alkyl, (C1-C4)alkyl, (C1-C3)alkyl, or -CH₃.

In an exemplary embodiment, i and j may be each independently 0, 1, 2, or 3.

In an exemplary embodiment, m may be an integer of 2 to 8, an integer of 2 to 6, an integer of 2 to 5, or 3.

In an exemplary embodiment, the transition metal compound may be a compound represented by the following Chemical Formula 1D:

[Chemical Formula 1D]

in Chemical Formula 1D,

M is a transition metal of Group 4 in the periodic table;

R^1d and R^8d are each independently hydrogen or (C1-C20)alkyl;

R^9d and R^10d are each independently (C1-C10)alkyl;

R^11d and R^13d are each independently halogen;

R^12d and R^14d are each independently hydrogen or (C1-C10)alkyl; and

n is an integer of 1 to 5.

In an exemplary embodiment, M may be Ti, Zr, or Hf.

In an exemplary embodiment, R^1d to R^8d may be each independently hydrogen, (C1-C10)alkyl, (C1-C8)alkyl, (C1-C6)alkyl, (C1-C5)alkyl, (C1-C4)alkyl, (C2-C6)alkyl, or tert-butyl.

In an exemplary embodiment, R^9d and R^10d may be each independently (C1-C8)alkyl, (C1-C6)alkyl, (C1-C5)alkyl, (C1-C4)alkyl, (C1-C3)alkyl, or -CH₃.

In an exemplary embodiment, R^11d and R^13d may be each independently -I, -Br, -Cl, or -F.

In an exemplary embodiment, R^12d and R^14d may be each independently hydrogen, (C1-C8)alkyl, (C1-C6)alkyl, (C1-C5)alkyl, (C1-C4)alkyl, (C1-C3)alkyl, or -CH₃.

In an exemplary embodiment, n may be 1, 2, 3, or 4.

In an exemplary embodiment, the compound represented by Chemical Formula 2A is a characteristic substituent that enables the transition metal compound according to an exemplary embodiment to achieve excellent activity, and specific examples thereof include

,

,

,

,

,

,

,

,

,

,

,

, and

. However, these compounds are only examples, and the present invention is not limited thereto.

In an exemplary embodiment, specific examples of the transition metal compound are as follows. However, the following compounds are only examples, and the transition metal compound is not limited thereto. The following compounds should be considered to achieve the desired effect in an exemplary embodiment or to include technical means that may solve the problem to be solved in an exemplary embodiment as long as they are represented by Chemical Formula 1A, Chemical Formula 1B, Chemical Formula 1C, or Chemical Formula 1D and at the same time, contain a carbazole group represented by Chemical Formula 2A.

Specifically, the transition metal compound according to an exemplary embodiment may be one or more of

The transition metal compound according to an exemplary embodiment contains a carbazole substituent, such that its solubility in a solvent is significantly improved, and specifically, its solubility in a hydrocarbon-based solvent is significantly improved. In particular, the transition metal compound according to an exemplary embodiment has an excellent solubility not only in an aromatic hydrocarbon-based solvent such as toluene, benzene, ethylbenzene, xylene, naphthalene, methylnaphthalene, anthracene, acenaphthene, or phenanthrene, but also in a non-aromatic hydrocarbon-based solvent such as methylcyclohexane, cyclohexane, n-heptane, n-hexane, n-butane, isobutane, n-pentane, n-octane, isooctane, nonane, decane, or dodecane. For example, the transition metal compound according to an exemplary embodiment may have a solubility in a hydrocarbon-based solvent at 25°C of 10 wt% or more, 12 wt% or more, 15 wt% or more, 17 wt% or more, 20 wt% or more, or 25 wt% or more. In an exemplary embodiment, the hydrocarbon-based solvent may be a non-aromatic hydrocarbon-based or aromatic hydrocarbon-based solvent. In particular, a solubility in an aromatic hydrocarbon-based solvent may be 20 wt% or more, 23 wt% or more, or 25 wt% or more. In addition, a solubility in a non-aromatic hydrocarbon-based solvent may be 10 wt% or more, 12 wt% or more, 15 wt% or more, or 17 wt% or more. An upper limit of the solubility may be 100 wt% or less, 80 wt% or less, 70 wt% or less, 65 wt% or less, 60 wt% or less, 55 wt% or less, 50 wt% or less, 30 wt% or less, or 25 wt% or less.

Another exemplary embodiment provides a transition metal catalyst composition containing the transition metal compound according to an exemplary embodiment and a cocatalyst, and in this case, the transition metal catalyst composition may be used for preparing an olefin polymer.

Regarding the transition metal compound, the description of the transition metal compound described above according to an exemplary embodiment may be applied, and the description thereof will be omitted below.

In an exemplary embodiment, the cocatalyst may contain one or more selected from an aluminum compound, a boron compound, and a mixture thereof.

In an exemplary embodiment, the boron compound may be selected from compounds represented by the following Chemical Formula 3A to Chemical Formula 3D:

[Chemical Formula 3A]

B(R^25a)₃

[Chemical Formula 3B]

[R^26a]⁺[B(R^25a)₄]^-

[Chemical Formula 3C]

[R^27a _pZH]⁺[R^25a ₄]^-

[Chemical Formula 3D]

in Chemical Formula 3A to Chemical Formula 3D,

B is boron;

R^25a's are each independently phenyl substituted or unsubstituted with one or more substituents selected from the group consisting of fluorine, (C1-C20)alkyl, fluorine-substituted (C1-C20)alkyl, (C1-C20)alkoxy, and fluorine-substituted (C1-C20)alkoxy;

R^26a is a (C5-C7) aromatic radical, a (C1-C20)alkyl(C6-C20)aryl radical, or a (C6-C20)aryl(C1-C20)alkyl radical;

Z is nitrogen or phosphorus;

R^27a's are each independently a (C1-C20)alkyl radical or a (C1-C10)alkyl-disubstituted anilinium radical;

R^28a is (C5-C20)alkyl;

R^29a is (C5-C20)aryl or (C1-C20)alkyl(C5-C20)aryl; and

p is 2 or 3.

In an exemplary embodiment, R^25a's may be each independently phenyl substituted or unsubstituted with one or more substituents selected from the group consisting of fluorine; fluorine-substituted or unsubstituted (C1-C15)alkyl, (C1-C10)alkyl, (C1-C8)alkyl, (C1-C6)alkyl, (C1-C5)alkyl, (C1-C4)alkyl, (C1-C3)alkyl, or (C2-C6)alkyl; and fluorine-substituted or unsubstituted (C1-C15)alkoxy, (C1-C10)alkoxy, (C1-C8)alkoxy, (C1-C6)alkoxy, (C1-C5)alkoxy, (C1-C4)alkoxy, (C1-C3)alkoxy, or (C2-C6)alkoxy.

In an exemplary embodiment, R^26a may be a (C5-C6) aromatic radical, a (C1-C10)alkyl(C6-C20)aryl radical, a (C1-C10)alkyl(C6-C15)aryl radical, a (C1-C10)alkyl(C6-C12)aryl radical, a (C1-C10)alkyl(C6-C10)aryl radical, a (C1-C10)alkyl(C6-C9)aryl radical, a (C6-C10)aryl(C1-C15)alkyl radical, a (C6-C10)aryl(C1-C10)alkyl radical, a (C6-C10)aryl(C1-C8)alkyl radical, a (C6-C10)aryl(C1-C6)alkyl radical, a (C6-C10)aryl(C1-C5)alkyl radical, a (C6-C10)aryl(C1-C4)alkyl radical, a (C6-C10)aryl(C1-C3)alkyl radical, or a (C6-C10)aryl(C2-C6)alkyl radical.

In an exemplary embodiment, R^27a's may be each independently a (C1-C15)alkyl radical, a (C1-C10)alkyl radical, a (C1-C8)alkyl radical, a (C1-C6)alkyl radical, a (C1-C5)alkyl radical, a (C1-C4)alkyl radical, a (C1-C3)alkyl radical, or a (C2-C6)alkyl radical; or an anilinium radical disubstituted with (C1-C10)alkyl, (C1-C8)alkyl, (C1-C6)alkyl, (C1-C5)alkyl, (C1-C4)alkyl, (C1-C3)alkyl, or (C2-C6)alkyl. The alkyl substituents disubstituted on the anilinium radical may be substituted on a nitrogen atom of anilinium.

In an exemplary embodiment, R^28a may be (C5-C15)alkyl, (C5-C10)alkyl, (C5-C8)alkyl, or (C5-C6)alkyl.

In an exemplary embodiment, R^29a may be (C5-C15)aryl, (C5-C10)aryl, (C5-C8)aryl, (C5-C6)aryl, (C1-C10)alkyl(C5-C20)aryl, (C1-C10)alkyl(C5-C15)aryl, (C1-C10)alkyl(C5-C10)aryl, (C1-C10)alkyl(C5-C8)aryl, or (C1-C10)alkyl(C5-C6)aryl.

In an exemplary embodiment, examples of the boron compound include trityl terakis(pentafluorophenyl)borate, tris(pentafluorophenyl)borane, tris(2,3,5,6-tetrafluorophenyl)borane, tris(2,3,4,5-tetrafluorophenyl)borane, tris(3,4,5-trifluorophenyl)borane, tris(2,3,4-trifluorophenyl)borane, phenyl-bis(pentafluorophenyl)borane, tetrakis(pentafluorophenyl)borate, tetrakis(2,3,5,6-tetrafluorophenyl)borate, tetrakis(2,3,4,5-tetrafluorophenyl)borate, tetrakis(3,4,5-trifluorophenyl)borate, tetrakis(2,2,4-trifluorophenyl)borate, phenyl-bis(pentafluorophenyl)borate, and tetrakis[3,5-bis(trifluoromethyl)phenyl]borate. In addition, examples of specific combinations thereof include ferrocenium tetrakis(pentafluorophenyl)borate, 1,1'-dimethylferrocenium tetrakis(pentafluorophenyl)borate, silver tetrakis(pentafluorophenyl)borate, triphenylmethyl tetrakis(pentafluorophenyl)borate, triphenylmethyl tetrakis[3,5-bis(trifluoromethyl)phenyl]borate, triethylammonium tetrakis(pentafluorophenyl)borate, tripropylammonium tetrakis(pentafluorophenyl)borate, trinormal butylammonium tetrakis(pentafluorophenyl)borate, trinormal butylammonium tetrakis(3,5-bis(trifluoromethyl)phenyl)borate, N,N-dimethylanilinium tetrakis(pentafluorophenyl)borate, N,N-diethylanilinium tetrakis(pentafluorophenyl)borate, N,N-2,4,6-pentamethylanilinium tetrakis(pentafluorophenyl)borate, N,N-dimethylanilinium tetrakis(3,5-bis(trifluoromethyl)phenyl)borate, diisopropylammonium tetrakis(pentafluorophenyl)borate, dicyclohexylammonium tetrakis(pentafluorophenyl)borate, triphenylphosphonium tetrakis(pentafluorophenyl)borate, trimethylphenylphosphonium tetrakis(pentafluorophenyl)borate, and tridimethylphenylphosphonium tetrakis(pentafluorophenyl)borate.

In an exemplary embodiment, the aluminum compound may be selected from an aluminoxane compound represented by the following Chemical Formula 4A or Chemical Formula 4B, an organoaluminum compound represented by the following Chemical Formula 4C, and an organoaluminum alkyloxide or an organoaluminum aryloxide compound represented by the following Chemical Formula 4D or Chemical Formula 4E:

[Chemical Formula 4A]

(-AlR^30a-O-)_m

[Chemical Formula 4B]

(R^31a)₂Al-(-OR^31a-)_q(-O-)Al(R^31a)₂

[Chemical Formula 4C]

(R^32a)_rAl(E)_3-r

[Chemical Formula 4D]

(R^33a)₂AlOR^34a

[Chemical Formula 4E]

R^33aAl(OR^34a)₂

in Chemical Formula 4A to Chemical Formula 4E,

R^30a and R^31a are each independently (C1-C20)alkyl;

m and q are each independently an integer of 5 to 20;

R^32a and R^33a are each independently (C1-C20)alkyl;

E is hydrogen or halogen;

r is an integer of 1 to 3; and

R^34a is (C1-C20)alkyl or (C6-C30)aryl.

In an exemplary embodiment, R^30a and R^31a may be each independently (C1-C15)alkyl, (C1-C10)alkyl, (C1-C8)alkyl, (C1-C6)alkyl, (C1-C5)alkyl, (C1-C4)alkyl, (C1-C3)alkyl, or (C2-C6)alkyl.

In an exemplary embodiment, m and q may be each independently an integer of 5 to 15, 5 to 10, or 5 to 8.

In an exemplary embodiment, R^32a and R^33a may be each independently (C1-C15)alkyl, (C1-C10)alkyl, (C1-C8)alkyl, (C1-C6)alkyl, (C1-C5)alkyl, (C1-C4)alkyl, (C1-C3)alkyl, or (C2-C6)alkyl.

In an exemplary embodiment, r may be 1, 2, or 3.

In an exemplary embodiment, R^34a may be (C1-C15)alkyl, (C1-C10)alkyl, (C1-C8)alkyl, (C1-C6)alkyl, (C1-C5)alkyl, (C1-C4)alkyl, (C1-C3)alkyl, (C2-C6)alkyl, (C6-C25)aryl, (C6-C20)aryl, (C6-C15)aryl, (C6-C10)aryl, (C6-C9)aryl, or (C6-C8)aryl.

In an exemplary embodiment, specific examples of the aluminum compound include methylaluminoxane, modified methylaluminoxane, and tetraisobutylaluminoxane; and examples of the organoaluminum compound include trialkylaluminum including trimethylaluminum, triethylaluminum, tripropylaluminum, triisobutylaluminum, and trihexylaluminum, dialkylaluminum chloride including dimethylaluminum chloride, diethylaluminum chloride, dipropylaluminum chloride, diisobutylaluminum chloride, and dihexylaluminum chloride, alkylaluminum dichloride including methylaluminum dichloride, ethylaluminum dichloride, propylaluminum dichloride, isobutylaluminum dichloride, and hexylaluminum dichloride, dialkylaluminum hydride including dimethylaluminum hydride, diethylaluminum hydride, dipropylaluminum hydride, diisobutylaluminum hydride, and dihexylaluminum hydride, and alkylalkoxyaluminum including methyldimethoxyaluminum, dimethylmethoxyaluminum, ethyldiethoxyaluminum, diethylethoxyaluminum, isobutyldibuthoxyaluminum, diisobutylbutoxyaluminum, hexyldimethoxyaluminum, dihexylmethoxyaluminum, and dioctylmethoxyaluminum.

In an exemplary embodiment, the olefin polymer may be an ethylene homopolymer or a copolymer of ethylene and α-olefin.

Still another exemplary embodiment provides a method for preparing an olefin polymer, the method including subjecting an olefin monomer to solution polymerization in the presence of the transition metal compound according to an exemplary embodiment, a cocatalyst, and a hydrocarbon-based solvent to obtain an olefin polymer.

The description described above may be applicable to the transition metal compound, the cocatalyst, and the olefin polymer, and the description thereof will be omitted below.

In an exemplary embodiment, the hydrocarbon-based solvent may be a C3-C20 non-aromatic hydrocarbon-based solvent, and may be, for example, one or more non-aromatic hydrocarbon-based solvents selected from the group consisting of methylcyclohexane, cyclohexane, n-heptane, n-hexane, n-butane, isobutane, n-pentane, n-octane, isooctane, nonane, decane, and dodecane. Alternatively, the hydrocarbon-based solvent may be a C3-C20 aromatic hydrocarbon-based solvent, and may be, for example, one or more aromatic hydrocarbon-based solvents selected from the group consisting of toluene, benzene, ethylbenzene, xylene, naphthalene, methylnaphthalene, anthracene, acenaphthene, and phenanthrene.

The transition metal compound according to an exemplary embodiment contains a carbazole substituent, such that its solubility in a solvent is significantly improved, and specifically, its solubility in a hydrocarbon-based solvent is significantly improved. In particular, the transition metal compound according to an exemplary embodiment has an excellent solubility not only in an aromatic hydrocarbon-based solvent such as toluene, benzene, ethylbenzene, xylene, naphthalene, methylnaphthalene, anthracene, acenaphthene, or phenanthrene, but also in a non-aromatic hydrocarbon-based solvent such as methylcyclohexane, cyclohexane, n-heptane, n-hexane, n-butane, isobutane, n-pentane, n-octane, isooctane, nonane, decane, or dodecane.

In an exemplary embodiment, the solution polymerization may be performed at 100°C to 200°C, 100°C to 180°C, 100°C to 150°C, 100°C to 140°C, 110°C to 130°C, or about 120°C.

In the method for preparing an olefin polymer according to an exemplary embodiment, a molar ratio of the transition metal compound to the cocatalyst may be 1:0.05 to 1:10,000.

In the method for preparing an olefin polymer according to an exemplary embodiment, a molar ratio of a transition metal in the transition metal compound to a boron atom in the cocatalyst may be 1:0.01 to 1:100 or 1:0.05 to 1:5. Alternatively, a molar ratio of the transition metal in the transition metal compound to an aluminum atom in the cocatalyst may be 1:10 to 1:1,000 or 1:25 to 1:500.

The method for preparing an olefin polymer according to an exemplary embodiment may be performed by bringing the transition metal compound, a cocatalyst, and ethylene, and as necessary, a vinyl-based comonomer into contact with each other under the presence of a hydrocarbon-based solvent. In this case, the transition metal compound, and the cocatalyst component may be separately added to a reactor, or the respective components may be mixed in advance and then added to the reactor, and mixing conditions such as the order of addition, temperature, and concentration are not particularly limited.

In an exemplary embodiment, when a copolymer of ethylene and α-olefin is prepared, (C3-C18) α-olefin may be used as a comonomer along with ethylene, and for example, the (C3-C18) α-olefin may be one or two or more selected from propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene, 1-hexadecene, and 1-octadecene. More specifically, 1-butene, 1-hexene, 1-octene, or 1-decene and ethylene may be copolymerized.

In an exemplary embodiment, a pressure of ethylene may be 1 atm to 1,000 atm or 10 atm to 150 atm.

The copolymer prepared by the preparation method according to an exemplary embodiment may contain a unit derived from ethylene in an amount of 30 wt% to 99 wt%, 30 wt% to 80 wt%, 50 wt% to 99 wt%, or 60 wt% to 99 wt%, with respect to the total weight.

In the method for preparing an olefin polymer according to an exemplary embodiment, linear low density polyethylene (LLDPE) produced using (C4-C10) α-olefin as a comonomer has a density range of 0.940 g/cc or less, and may be extended to the range of very low density polyethylene (VLDPE) or ultra-low density polyethylene (ULDPE) having a density range of 0.900 g/cc or less or an olefin elastomer. In addition, in an exemplary embodiment, hydrogen may be used as a molecular weight regulator for regulating the molecular weight in the preparation of the ethylene copolymer, and the prepared copolymer may have a weight average molecular weight (Mw) of 80,000 g/mol to 500,000 g/mol.

As a specific example of an olefin-diene copolymer prepared using the catalyst composition according to an exemplary embodiment, an ethylene-propylene-diene copolymer having a content of ethylene (or a unit derived from ethylene) of 30 wt% to 80 wt%, a content of propylene (or a unit derived from propylene) of 20 wt% to 70 wt%, and a content of diene (or a unit derived from diene) of 0 wt% to 15 wt% may be prepared. A diene monomer that may be used in an exemplary embodiment has two or more double bonds, and may be one or two or more selected from 1,4-hexadiene, 1,5-hexadiene, 1,5-heptadiene, 1,6-heptadiene, 1,6-octadiene, 1,7-octadiene, 1,7-nonadiene, 1,8-nonadiene, 1,8-decadiene, 1,9-decadiene, 1,12-tetradecadiene, 1,13-tetradecadiene, 3-methyl-1,4-hexadiene, 3-methyl-1,5-hexadiene, 3-ethyl-1,4-hexadiene, 3-ethyl-1,5-hexadiene, 3,3-dimethyl-1,4-hexadiene, 3,3-dimethyl-1,5-hexadiene, 5-vinyl-2-norbornene, 2,5-norbornadiene, 7-methyl-2,5-norbornadiene, 7-ethyl-2,5-norbornadiene, 7-propyl-2,5-norbornadiene, 7-butyl-2,5-norbornadiene, 7-phenyl-2,5-norbornadiene, 7-hexyl-2,5-norbornadiene, 7,7-dimethyl-2,5-norbornadiene, 7-methyl-7-ethyl-2,5-norbornadiene, 7-chloro-2,5-norbornadiene, 7-bromo-2,5-norbornadiene, 7-fluoro-2,5-norbornadiene, 7,7-dichloro-2,5-norbornadiene, 1-methyl-2,5-norbornadiene, 1-ethyl-2,5-norbornadiene, 1-propyl-2,5-norbornadiene, 1-butyl-2,5-norbornadiene, 1-chloro-2,5-norbornadiene, 1-bromo-2,5-norbornadiene, 5-isopropyl-2-norbornene, 1,4-cyclohexadiene, bicyclo[2.2.1]hepta-2,5-diene, 5-ethylidene-2-norbornene, 5-methylene-2-norbornene, bicyclo[2.2.2]octa-2,5-diene, 4-vinyl-cyclohex-1-ene, bicyclo[2.2.2]octa-2,6-diene, 1,7,7-trimethylbicyclo[2.2.1]hepta-2,5-diene, dicyclopentadiene, phenyltetrahydroindene, 5-arylbicyclo[2.2.1]hepta-2-ene, 1,5-cyclooctadiene, 1,4-diarylbenzene, butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 1,3-butadiene, 4-methyl-1,3-pentadiene, 1,3-pentadiene, 3-methyl-1,3-pentadiene, 2,4-dimethyl-1,3-pentadiene, and 3-ethyl-1,3-pentadiene. The diene monomer may be selected depending on processing characteristics of the ethylene-propylene-diene copolymer.

In general, in a case where an ethylene-proylene-diene copolymer is prepared, when a content of propylene increases, the molecular weight of the copolymer decreases, but in a case where the ethylene-proylene-diene copolymer according to an exemplary embodiment is prepared, even when the content of propylene increases to 50 wt%, a product having a relatively high molecular weight may be prepared without a reduction in molecular weight.

Since the catalyst composition presented in the present specification is present in a homogeneous form in a polymerization reactor, it may be more appropriate to apply the catalyst composition to a solution polymerization process performed at a temperature equal to or higher than a melting point of the corresponding polymer. However, as disclosed in U.S. Patent No. 4,752,597, the catalyst composition may be used in a slurry polymerization or gas phase polymerization process in the form of a heterogeneous catalyst composition obtained by supporting the transition metal compound and the cocatalyst on a porous metal oxide support.

Hereinafter, a novel transition metal compound according to an exemplary embodiment, a catalyst composition containing the same, and a method for preparing an olefin polymer using the same will be described in detail with reference to Examples and Experimental Examples. However, Examples and Experimental Examples to be described below are only to illustrate some exemplary embodiments, and the technology described in the present specification is not construed as being limited thereto.

Unless otherwise stated, all experiments of synthesizing ligands and catalysts were carried out using a standard Schlenk or glove box technique under a nitrogen atmosphere, and an organic solvent used in the reaction was used after refluxing the solvent in the presence of a sodium metal and benzophenone to remove moisture, and distilling the solvent immediately before use. The ¹H-NMR analysis of the synthesized ligand and catalyst was carried out using Bruker 400 or 500 MHz at room temperature.

Methylcyclohexane as a polymerization solvent was used after passing through a tube filled with 5 Å molecular sieves and activated alumina, and being bubbled with high-purity nitrogen to sufficiently remove moisture, oxygen, and other catalyst poisoning materials.

<Comparative Example 1>

With reference to Korean Patent Laid-Open Publication Nos. 10-2018-0048728 and 10-2019-0075778, a transition metal compound C1 was prepared using 4-methylphenol as a starting material.

<Comparative Example 2>

The reaction was performed in a glove box under a nitrogen atmosphere. The ligand compound L1 (0.89 g, 0.858 mmol) and toluene (20 mL) were added to a 100 mL flask, tetrachlorozircholium (0.2 g, 0.858 mmol) was added thereto, stirring was performed at room temperature for 4 hours, and then a solvent was removed. A transition metal compound C2 (0.56 g, 55%) of Comparative Example 2 was obtained as a white solid dried in vacuum.

¹H NMR (CDCl₃): δ 8.34 (s, 2H), 8.10 (s, 2H), 7.45-7.00 (m, 14H), 6.42-6.37 (m, 2H), 4.78-4.16 (m, 2H), 4.17-4.13 (m, 2H) 3.66-3.63 (m, 2H), 2.38 (s, 6H) 1.71-1.55 (m, 2H), 1.49 (s,18H), 1.33 (s, 18H).

<Comparative Example 3>

The reaction was performed in a glove box under a nitrogen atmosphere. The transition metal compound C1 (0.8 g, 0.873 mmol) of Comparative Example 1 and toluene (40 mL) were added to a 100 mL flask, 3-pentadecylphenol (0.54 g, 1.758 mmol) was added thereto, stirring was performed at room temperature for 2 hours, and then a solvent was removed. The mixture was dissolved in 50 mL of normal hexane, and then a solid was removed by filtration with a filter filled with dried celite. The filtered solution was vacuum-dried to obtain a transition metal compound C3 (1.36 g, 90%) of Comparative Example 3 as a white solid.

¹H NMR (CDCl₃): δ 8.36 (s, 2H), 8.25 (s, 2H), 7.44-7.00 (m, 14H), 6.72 (m, 2H), 6.60 (m, 2H), 6.33 (m, 2H), 5.85 (m, 2H), 5.58 (s, 2H), 4.94 (m, 2H), 4.67 (m, 2H), 4.15 (m, 2H), 3.69 (m, 2H), 2.32 (s, 6H), 2.30(m, 4H), 1.56-1.26 (m, 52H), 1.51 (s, 18H), 1.40 (s, 18H), 0.90 (m, 6H).

<Example 1>

The reaction was performed in a glove box under a nitrogen atmosphere. The transition metal compound C2 (0.5 g, 0.42 mmol) of Comparative Example 2 and toluene (20 mL) were added to a 100 mL flask, 3,6-ditert-butyl-9H-carbazole (0.24 g, 0.84 mmol) was added thereto, stirring was performed at room temperature for 2 hours, and then a solvent was removed. The mixture was dissolved in 50 mL of normal hexane, and then a solid was removed by filtration with a filter filled with dried celite. The filtered solution was vacuum-dried to obtain a transition metal compound C4 (0.54 g, 76.7%) of Example 1 as a yellow solid.0

¹H NMR (CDCl₃): δ 8.57 (s, 2H), 8.47 (s, 2H), 7.66 (d, 2H), 7.53 (d, 2H), 7.44-7.19 (m, 14H), 7.02 (d, 2H), 6.82 (s, 2H), 6.68 (m, 2H), 6.50 (d, 2H), 6.06-6.03 (m, 2H), 5.67-5.64 (m, 2H) 4.79 (m, 2H), 4.16 (m, 2H), 2.28-2.24 (m, 2H), 2.11 (s, 6H) 1.60-1.18 (s, 72H).

<Example 2>

The reaction was performed in a glove box under a nitrogen atmosphere. The transition metal compound C2 (0.5 g, 0.42 mmol) of Comparative Example 2 and toluene (20 mL) were added to a 100 mL flask, 3,6-bis(2-ethylhexyl)-9H-carbazole (0.34 g, 0.87 mmol) was added thereto, stirring was performed at room temperature for 2 hours, and then a solvent was removed. The mixture was dissolved in 50 mL of normal hexane, and then a solid was removed by filtration with a filter filled with dried celite. The filtered solution was vacuum-dried to obtain a transition metal compound C5 (0.73 g, 91.5%) of Example 2 as a yellow solid.

¹H NMR (CDCl₃): δ 8.50 (s, 4H), 7.67 (d, 2H), 7.53 (m, 4H), 7.42 (m, 4H), 7.23 (m, 2H). 7.15 (d, 2H), 6.85 (m, 6H), 6.70 (s, 2H), 5.99 (m, 2H), 5.91 (d, 1H), 5.85 (d, 1H), 5,45 (sept, 2H), 5.28 (t, 2H), 4.84 (t, 2H), 4.20 (t, 2H), 2,65-2.33 (m, 10H), 2.14 (s, 6H), 1.67 (m, 4H), 1.59 (s, 18H), 1.50 (s, 18H), 1.55-1.05 (m, 32H), 0.95 (m, 12H), 0.79 (m, 12H).

<Example 3>

The reaction was performed in a glove box under a nitrogen atmosphere. The transition metal compound C2 (0.5 g, 0.42 mmol) of Comparative Example 2 and toluene (20 mL) were added to a 100 mL flask, 3,6-didodecyl-9H-carbazole (0.44 g, 0.87 mmol) was added thereto, stirring was performed at room temperature for 2 hours, and then a solvent was removed. The mixture was dissolved in 50 mL of normal hexane, and then a solid was removed by filtration with a filter filled with dried celite. The filtered solution was vacuum-dried to obtain a transition metal compound C6 (0.74 g, 82.9%) of Example 3 as a yellow solid.

¹H NMR (CDCl₃): δ 8.52 (s, 4H), 7.70 (d, 2H), 7.54 (m, 4H), 7.44 (d, 2H), 7.40 (d, 2H), 7.26 (s, 2H), 7.19 (s, 2H), 6.89-6.83 (m, 6H), 6.72 (s, 2H), 6.02 (dd, 2H), 5.85 (dd, 2H), 5.43-5.30 (m, 4H), 4.83 (p, 2H), 4.20 (p, 2H), 2.71-2.50 (m, 8H), 2.40 (m, 2H), 2.15 (s, 6H), 1.61 (s, 18H), 1.57 (s, 18H), 1.60-1.15 (m, 80H), 0.97-0.88 (m, 12H).

<Example 4>

The reaction was performed in a glove box under a nitrogen atmosphere. The transition metal compound C2 (0.5 g, 0.42 mmol) of Comparative Example 2 and toluene (20 mL) were added to a 100 mL flask, 3,6-bis(2-ethylhex-1-en-1-yl)-9H-carbazole (0.34 g, 0.87 mmol) was added thereto, stirring was performed at room temperature for 2 hours, and then a solvent was removed. The mixture was dissolved in 50 mL of normal hexane, and then a solid was removed by filtration with a filter filled with dried celite. The filtered solution was vacuum-dried to obtain a transition metal compound C7 (0.66 g, 83.0%) of Example 4 as a yellow solid.

¹H NMR (CDCl₃): δ 8.50 (s, 4H), 7.71-7.60 (m, 4H), 7.56-7.46 (m, 4H), 7.42-7.33 (m, 4H), 7.28-7.20 (m, 2H), 7.01 (m, 2H), 6.95 (t, 1H), 6.89 (d, 1H), 6.86 (s, 2H), 6.73 (s, 2H), 6.49 (d, 2H), 6.48 (s, 2H), 6.07 (m, 2H), 5.63 (m, 2H), 5.42 (m, 2H), 5.36 (t, 2H), 4.89 (p, 2H), 4.24 (p, 2H), 2.42-2.11 (m, 18H), 2.16 (s, 6H), 1.60 (s, 18H), 1.54 (s, 18H), 1.52-1.05 (m, 40H), 1.02-0.91 (m, 12H).

<Example 5>

The reaction was performed in a glove box under a nitrogen atmosphere. The transition metal compound C8 (0.5 g, 0.42 mmol) and toluene (20 mL) were added to a 100 mL flask, 3,6-bis(2-ethylhexyl)-9H-carbazole (0.38 g, 0.87 mmol) was added thereto, stirring was performed at room temperature for 2 hours, and then a solvent was removed. The mixture was dissolved in 50 mL of normal hexane, and then a solid was removed by filtration with a filter filled with dried celite. The filtered solution was vacuum-dried to obtain a transition metal compound C9 (0.44 g, 56 %) of Example 5 as a yellow solid.

¹H NMR (CDCl₃): δ 8.21 (d, 2H), 8.13 (d, 2H), 7.74 (s, 4H), 7.44-7.02 (m, 10H), 6.78 (d, 2H), 6.65 (s, 4H), 5.88 (d, 2H), 5.34 (m, 2H), 5.17 (m, 2H), 4.87(m, 2H), 4.65 (m, 2H), 4.06 (m, 2H), 3.38 (m, 2H), 2.63-2.29 (s, 10H), 2.13 (s, 6H), 1.91 (m, 4H), 1.66 (s, 18H), 1.57 (s, 18H), 1.72-0.61 (m, 56H).

<Example 6>

The reaction was performed in a glove box under a nitrogen atmosphere. The transition metal compound C10 (0.5 g, 0.42 mmol) and toluene (20 mL) were added to a 100 mL flask, 3,6-bis(2-ethylhexyl)-9H-carbazole (0.38 g, 0.87 mmol) was added thereto, stirring was performed at room temperature for 2 hours, and then a solvent was removed. The mixture was dissolved in 50 mL of normal hexane, and then a solid was removed by filtration with a filter filled with dried celite. The filtered solution was vacuum-dried to obtain a transition metal compound C11 (0.73 g, 90.8%) of Example 6 as a yellow solid.

¹H NMR (CDCl₃): δ 8.52 (s, 2H), 8.49 (s, 2H), 7.53 (d, 2H), 7.58-7.51 (m, 4H), 7.46 (m, 4H), 7.38 (d, 2H), 7.23 (s, 2H), 7.20 (d, 2H), 7.06 (m, 2H), 6.90 (d, 2H), 6.85 (s, 2H), 6.73 (s, 2H), 6.04 (m, 2H), 5.96 (m, 2H), 5.76 (m, 2H), 5.35 (t, 2H), 5.04 (t, 2H), 4.41 (p, 2H), 2.66-2.41 (m, 10H), 2.18 (s, 6H), 1.81 (m, 4H), 1.62 (s, 18H), 1.59 (s, 18H), 1.52-1.14 (m, 32H), 0.97 (m, 12H), 0.81 (m, 12H).

<Experimental Example 1> Measurement of Solubility

In order to compare the solubilities of the transition metal compounds prepared by Examples and Comparative Examples in solvents, the following experiment was performed. Specifically, 1.0 g of each of the transition metal compounds prepared in Examples and Comparative Examples was dissolved in each of solvents (toluene, methylcyclohexane, and n-hexane) shown in the following table at 25°C under a nitrogen atmosphere to prepare a saturated solution, and then a solid was removed with a 0.45 μm filter. At this time, in Example 1 and Comparative Examples 1 to 3, the transition metal compound was dissolved in 2.34 g of the solvent, and in Examples 2 to 6, the transition metal compound was dissolved in 1.0 g of the solvent. The solvent was completely removed, a weight of the remaining transition metal compound was measured, and a solubility of the transition metal compound was calculated using the measured weight. The results were shown in Table 1. A case where the transition metal compound was insoluble in the solvent was indicated as "-".

	Solubility (wt%)
	Toluene	Methylcyclohexane	n-Hexane
Example 1	26.4	20.4	17.7
Example 2	50.0	25.4	31.0
Example 3	42.7	35.5	40.0
Example 4	44.0	37.8	36.6
Example 5	50.0	45.0	25.0
Example 6	48.8	40.4	37.0
Comparative Example 1	3.5	0.7	-
Comparative Example 2	1.1	-	-
Comparative Example 3	13.5	9.5	9.3

As shown in Table 1, it could be appreciated that in the cases of the transition metal compoundsㅇprepared in Examples, the solubility in the hydrocarbon-based solvent was significantly higher than those of the transition metal compounds of Comparative Examples 1 to 3, and in particular, the solubility in the non-aromatic hydrocarbon-based solvent was significantly improved.

<Examples 7 to 12> Copolymerization of Ethylene and 1-Octene

600 mL of heptane and 80 mL of 1-octene were added to a stainless steel reactor having a capacity of 1,500 mL, the inside of which was purged with nitrogen after sufficient drying, and then 2 mL of triisobutylaluminum (1.0 M hexane solution) was added to the reactor. Thereafter, the temperature of the reactor was increased, 1.0 wt% of each of the transition metal compounds prepared in Examples 1 to 6 and 0.4 mL of a toluene solution were added, the reactor was filled with ethylene so that the pressure in the reactor was 20 kg/cm², and then ethylene was continuously supplied to allow polymerization to proceed. The reaction was performed for 5 minutes, and then the recovered reaction product was dried in a vacuum oven at 40°C for 8 hours.

<Comparative Example 4>

Polymerization was performed in the same manner as that of Example 7 using the transition metal compound of Comparative Example 3 as a catalyst instead of the transition metal compound of Example 1.

The temperature change (ΔT) and catalytic activity of the catalyst during the polymerization process of each of Examples 7 to 12 and Comparative Example 4 were shown in Table 2.

	ΔT (°C)	Catalytic activity (kg/amount of catalyst used(mmol))
Example 7	47.9	37.96
Example 8	50.7	62.40
Example 9	48.1	30.76
Example 10	49.1	38.51
Example 11	38.6	31.50
Example 12	33.3	23.64
Comparative Example 4	30.4	21.74

Referring to Table 2, it could be confirmed that in the cases of the transition metal compounds of Examples, the temperature change and catalytic activity were all significantly higher than those of the transition metal compound of Comparative Example 3.

Through this, it may be appreciated that since the transition metal compounds of Examples have a structure into which an alkyl-substituted carbazole-based leaving group is introduced, the solubility in the hydrocarbon-based solvent is significantly higher than those of the transition metal compounds of Comparative Examples, such that the transition metal compound according to an exemplary embodiment is significantly easily used in a solution process, and the catalytic activity is significantly improved to be beneficial for commercial plant applications.

In particular, the transition metal compound according to an exemplary embodiment has an excellent solubility even in a non-aromatic hydrocarbon-based solvent, such that the transition metal compound according to an exemplary embodiment may replace an existing aromatic solvent that may be harmful to the environment and the human body, which is environmentally friendly and useful.

As set forth above, the present disclosure relates to a novel transition metal compound, a transition metal catalyst composition for preparing an olefin polymer containing the same, and a method for preparing an olefin polymer using the same. The transition metal compound according to an exemplary embodiment may have a significantly improved solubility in a hydrocarbon-based solvent by introducing a carbazole functional group, such that the catalytic activity may be maintained without deterioration during solution polymerization. In addition, the transition metal compound according to an exemplary embodiment may efficiently improve the polymerization process and may be significantly advantageous for commercialization because injection, transfer, and the like of the transition metal compound are easy during a solution process.

Further, since the transition metal compound according to an exemplary embodiment has excellent reactivity with an olefin monomer due to an excellent solubility in a hydrocarbon-based solvent, when the transition metal compound according to an exemplary embodiment is used as a catalyst, olefin polymerization may be significantly efficiently performed, and therefore, an olefin polymer may be prepared with a high yield using the same.

Further, in the method for preparing an olefin polymer according to an exemplary embodiment, a transition metal compound having an excellent solubility in a hydrocarbon-based solvent is used as a main catalyst, such that transfer, injection, and the like of the catalyst may be easy and more environmentally friendly, which may enable an olefin polymer to be efficiently prepared.

Hereinabove, an exemplary embodiment has been described in detail through Examples and Experimental Examples, but the scope of an exemplary embodiment is not limited to a specific exemplary embodiment, and should be interpreted according to the appended claims.

Claims (21)

1. A transition metal compound represented by the following Chemical Formula 1A:

   [Chemical Formula 1A]

   

   in Chemical Formula 1A,

   M is a transition metal of Group 4 in the periodic table;

   Y's are each independently -O-, -S-, -NR^1aa-, or -PR^2aa-; R^1aa and R^2aa are each independently hydrogen, (C1-C20)hydrocarbylene, (C1-C20)alkoxylene, (C6-C20)aryloxylene, or (C1-C20)alkylsilyl; and the hydrocarbylene, alkoxylene, aryloxylene, and alkylsilyl of Y may be substituted with halogen;

   L is a linker with 1 to 50 atoms excluding hydrogen; and

   R^1a to R^16a are each independently hydrogen, halogen, (C1-C30)heterohydrocarbyl, (C1-C30)hydrocarbyl, (C1-C30)alkoxy, (C6-C30)aryloxy, (C1-C30)alkylsilyl, (C1-C30)alkylboryl, (C1-C30)alkylamino, (C1-C30)diallylamino, (C1-C30)alkylphosphino, (C1-C30)alkylthio, or (C6-C30)arylthio, or represented by the following Chemical Formula 5A; the heterohydrocarbyl, hydrocarbyl, alkoxy, aryloxy, alkylsilyl, alkylboryl, alkylamino, alkylphosphino, alkylthio, and arylthio of R^1a to R^16a may be substituted with halogen, or adjacent substituents of R^1a to R^16a may be linked to each other to form an alicyclic ring or an aromatic ring; and the alicyclic ring and the aromatic ring may be substituted with one or more selected from the group consisting of (C1-C20)alkyl, (C1-C20)alkoxy, (C1-C20)alkoxy(C1-C20)alkyl, (C6-C20)aryl, (C6-C20)aryl(C1-C20)alkyl, (C1-C20)alkyl(C6-C20)aryl, (C1-C20)alkylsilyl, and (C6-C20)arylsilyl,

   [Chemical Formula 5A]

   

   in Chemical Formula 5A,

   R^35a to R^42a are each independently hydrogen, (C1-C30)alkyl, (C1-C30)alkylsilyl, (C1-C30)alkoxy, (C3-C30)cycloalkyl, (C6-C30)aryl, (C6-C30)aryl(C1-C30)alkyl, or (C1-C30)alkyl(C6-C30)aryl; and

   X's are each independently represented by the following Chemical Formula 2A,

   [Chemical Formula 2A]

   

   in Chemical Formula 2A,

   R^17a to R^24a are each independently hydrogen, (C1-C30)alkyl, (C2-C30)alkenyl, (C2-C30)alkynyl, (C1-C30)alkylsilyl, (C1-C30)alkoxy, (C3-C30)cycloalkyl, (C6-C30)aryl, (C6-C30)aryl(C1-C30)alkyl, or (C1-C30)alkyl(C6-C30)aryl; the alkyl, alkylsilyl, alkoxy, cycloalkyl, aryl, arylalkyl, and alkylaryl of R^17a to R^24a may be substituted with one or more selected from the group consisting of halogen, (C1-C10)alkyl, (C1-C10)alkylamino, (C1-C10)alkoxy, and (C1-C10)alkylsilyl; or adjacent substituents of R^17a to R^24a may be linked to (C3-C12)alkylene or (C3-C12)alkenylene with or without a fused ring to form an alicyclic ring or an aromatic ring; and the alicyclic ring or the aromatic ring may be substituted with one or more selected from the group consisting of (C1-C20)alkyl, (C1-C20)alkoxy, (C1-C20)alkoxy(C1-C20)alkyl, (C6-C20)aryl, (C6-C20)aryl(C1-C20)alkyl, (C1-C20)alkyl(C6-C20)aryl, (C1-C20)alkylsilyl, and (C6-C20)arylsilyl.
2. The transition metal compound of claim 1, wherein

   Y's are each independently -O-, -S-, -NR^1aa-, or -PR^2aa-; R^1aa and R^2aa are each independently hydrogen, (C1-C10)hydrocarbylene, (C1-C10)alkoxylene, (C6-C10)aryloxylene, or (C1-C10)alkylsilyl; and the hydrocarbylene, alkoxylene, aryloxylene, and alkylsilyl of Y may be substituted with halogen;

   L is (C1-C10)alkylene;

   R^1a to R^16a are each independently hydrogen, halogen, (C1-C20)heterohydrocarbyl, (C1-C20)hydrocarbyl, (C1-C20)alkoxy, or (C6-C20)aryloxy, or represented by Chemical Formula 5A; the heterohydrocarbyl, hydrocarbyl, alkoxy, and aryloxy of R^1a to R^16a may be substituted with halogen; or adjacent substituents of R^1a to R^16a may be linked to each other to form an alicyclic ring or an aromatic ring; and the alicyclic ring and the aromatic ring may be substituted with one or more selected from the group consisting of (C1-C20)alkyl, (C1-C20)alkoxy, (C1-C20)alkoxy(C1-C20)alkyl, (C6-C20)aryl, (C6-C20)aryl(C1-C20)alkyl, (C1-C20)alkyl(C6-C20)aryl, (C1-C20)alkylsilyl, and (C6-C20)arylsilyl; and

   R^35a to R^42a are each independently hydrogen, (C1-C20)alkyl, (C1-C20)alkylsilyl, (C1-C20)alkoxy, (C3-C20)cycloalkyl, (C6-C20)aryl, (C6-C20)aryl(C1-C20)alkyl, or (C1-C20)alkyl(C6-C20)aryl.
3. The transition metal compound of claim 1, wherein R^17a to R^24a are each independently hydrogen, (C1-C20)alkyl, (C2-C20)alkenyl, (C2-C20)alkynyl, (C1-C20)alkylsilyl, (C1-C20)alkoxy, (C3-C20)cycloalkyl, (C6-C20)aryl, (C6-C20)aryl(C1-C20)alkyl, or (C1-C20)alkyl(C6-C20)aryl; the alkyl, alkylsilyl, alkoxy, cycloalkyl, aryl, arylalkyl, and alkylaryl of R^17a to R^24a may be substituted with one or more selected from the group consisting of halogen, (C1-C10)alkyl, (C1-C10)alkylamino, (C1-C10)alkoxy, and (C1-C10)alkylsilyl; or adjacent substituents of R^17a to R^24a may be linked to (C3-C12)alkylene or (C3-C12)alkenylene with or without a fused ring to form an alicyclic ring or an aromatic ring; and the alicyclic ring or the aromatic ring may be substituted with one or more selected from the group consisting of (C1-C20)alkyl, (C1-C20)alkoxy, (C1-C20)alkoxy(C1-C20)alkyl, (C6-C20)aryl, (C6-C20)aryl(C1-C20)alkyl, (C1-C20)alkyl(C6-C20)aryl, (C1-C20)alkylsilyl, and (C6-C20)arylsilyl.
4. The transition metal compound of claim 1, wherein the transition metal compound is represented by the following Chemical Formula 1B:

   [Chemical Formula 1B]

   

   in Chemical Formula 1B,

   M is a transition metal of Group 4 in the periodic table;

   R^1b to R^4b are each independently hydrogen, (C1-C20)alkyl, (C6-C20)aryl, or (C6-C20)aryl(C1-C20)alkyl;

   R^5b and R^6b are each independently hydrogen or (C1-C20)alkyl;

   R^7b and R^8b are each independently hydrogen, halogen, or (C1-C20)alkyl;

   a, b, c, d, e, f, g, and h are each independently an integer of 0 to 4; and

   m is an integer of 2 to 10.
5. The transition metal compound of claim 1, wherein the transition metal compound is represented by the following Chemical Formula 1C:

   [Chemical Formula 1C]

   

   in Chemical Formula 1C,

   M is a transition metal of Group 4 in the periodic table;

   R^1c to R^8c are each independently hydrogen, (C1-C20)alkyl, (C6-C20)aryl, or (C6-C20)aryl(C1-C20)alkyl;

   R^9c and R^10c are each independently (C1-C20)alkyl;

   R^11c and R^13c are each independently halogen or (C1-C20)alkyl;

   R^12c and R^14c are each independently hydrogen or (C1-C20)alkyl;

   i and j are each independently an integer of 0 to 3; and

   m is an integer of 2 to 10.
6. The transition metal compound of claim 1, wherein the transition metal compound is represented by the following Chemical Formula 1D:

   [Chemical Formula 1D]

   

   in Chemical Formula 1D,

   M is a transition metal of Group 4 in the periodic table;

   R^1d and R^8d are each independently hydrogen or (C1-C20)alkyl;

   R^9d and R^10d are each independently (C1-C10)alkyl;

   R^11d and R^13d are each independently halogen;

   R^12d and R^14d are each independently hydrogen or (C1-C10)alkyl; and

   n is an integer of 1 to 5.
7. The transition metal compound of claim 6, wherein

   M is Ti, Zr, or Hf;

   R^1d and R^8d are each independently hydrogen or (C1-C5)alkyl;

   R^9d and R^10d are each independently (C1-C5)alkyl;

   R^11d and R^13d are each independently -F or -Cl;

   R^12d and R^14d are each independently hydrogen or (C1-C5)alkyl; and

   n is an integer of 1 to 5.
8. The transition metal compound of claim 1, wherein the compound represented by Chemical Formula 2A is any one selected from the group consisting of compounds:

   

   ,

   

   ,

   

   ,

   

   ,

   

   ,

   

   ,

   

   ,

   

   ,

   

   ,

   

   ,

   

   ,

   

   , and

   

   .
9. The transition metal compound of claim 1, wherein the transition metal compound is any one selected from the group consisting of compounds:

   

   

   

   

   

   

   

   

   

   

   

   

   

   

   

   

   

   

   

   

   

   

   

   

   

   

   

   

   

   

   

   

   

   

   

   

   

   

   

   

   

   

   

   .
10. The transition metal compound of claim 1, wherein the transition metal compound is any one selected from the group consisting of compounds:

    

    

    

    

    

    

    

    .
11. The transition metal compound of claim 1, wherein the transition metal compound has a solubility in a hydrocarbon-based solvent at 25°C of 10 wt% or more.
12. A transition metal catalyst composition for preparing an olefin polymer, the transition metal catalyst composition comprising:

    a transition metal compound represented by the following Chemical Formula 1A; and

    a cocatalyst,

    [Chemical Formula 1A]

    

    in Chemical Formula 1A,

    M is a transition metal of Group 4 in the periodic table;

    Y's are each independently -O-, -S-, -NR^1aa-, or -PR^2aa-; R^1aa and R^2aa are each independently hydrogen, (C1-C20)hydrocarbylene, (C1-C20)alkoxylene, (C6-C20)aryloxylene, or (C1-C20)alkylsilyl; and the hydrocarbylene, alkoxylene, aryloxylene, and alkylsilyl of Y may be substituted with halogen;

    L is a linker with 1 to 50 atoms excluding hydrogen; and

    R^1a to R^16a are each independently hydrogen, halogen, (C1-C30)heterohydrocarbyl, (C1-C30)hydrocarbyl, (C1-C30)alkoxy, (C6-C30)aryloxy, (C1-C30)alkylsilyl, (C1-C30)alkylboryl, (C1-C30)alkylamino, (C1-C30)diallylamino, (C1-C30)alkylphosphino, (C1-C30)alkylthio, or (C6-C30)arylthio, or represented by the following Chemical Formula 5A; the heterohydrocarbyl, hydrocarbyl, alkoxy, aryloxy, alkylsilyl, alkylboryl, alkylamino, alkylphosphino, alkylthio, and arylthio of R^1a to R^16a may be substituted with halogen, or adjacent substituents of R^1a to R^16a may be linked to each other to form an alicyclic ring or an aromatic ring; and the alicyclic ring and the aromatic ring may be substituted with one or more selected from the group consisting of (C1-C20)alkyl, (C1-C20)alkoxy, (C1-C20)alkoxy(C1-C20)alkyl, (C6-C20)aryl, (C6-C20)aryl(C1-C20)alkyl, (C1-C20)alkyl(C6-C20)aryl, (C1-C20)alkylsilyl, and (C6-C20)arylsilyl,

    [Chemical Formula 5A]

    

    in Chemical Formula 5A,

    R^35a to R^42a are each independently hydrogen, (C1-C30)alkyl, (C1-C30)alkylsilyl, (C1-C30)alkoxy, (C3-C30)cycloalkyl, (C6-C30)aryl, (C6-C30)aryl(C1-C30)alkyl, or (C1-C30)alkyl(C6-C30)aryl; and

    X's are each independently represented by the following Chemical Formula 2A,

    [Chemical Formula 2A]

    

    in Chemical Formula 2A,

    R^17a to R^24a are each independently hydrogen, (C1-C30)alkyl, (C2-C30)alkenyl, (C2-C30)alkynyl, (C1-C30)alkylsilyl, (C1-C30)alkoxy, (C3-C30)cycloalkyl, (C6-C30)aryl, (C6-C30)aryl(C1-C30)alkyl, or (C1-C30)alkyl(C6-C30)aryl; the alkyl, alkylsilyl, alkoxy, cycloalkyl, aryl, arylalkyl, and alkylaryl of R^17a to R^24a may be substituted with one or more selected from the group consisting of halogen, (C1-C10)alkyl, (C1-C10)alkylamino, (C1-C10)alkoxy, and (C1-C10)alkylsilyl; or adjacent substituents of R^17a to R^24a may be linked to (C3-C12)alkylene or (C3-C12)alkenylene with or without a fused ring to form an alicyclic ring or an aromatic ring; and the alicyclic ring or the aromatic ring may be substituted with one or more selected from the group consisting of (C1-C20)alkyl, (C1-C20)alkoxy, (C1-C20)alkoxy(C1-C20)alkyl, (C6-C20)aryl, (C6-C20)aryl(C1-C20)alkyl, (C1-C20)alkyl(C6-C20)aryl, (C1-C20)alkylsilyl, and (C6-C20)arylsilyl.
13. The transition metal catalyst composition of claim 12, wherein the cocatalyst contains one or more selected from an aluminum compound, a boron compound, and a mixture thereof.
14. The transition metal catalyst composition of claim 12, wherein the olefin polymer is an ethylene homopolymer or a copolymer of ethylene and α-olefin.
15. A method for preparing an olefin polymer, the method comprising subjecting an olefin monomer to solution polymerization in the presence of a transition metal compound represented by the following Chemical Formula 1A, a cocatalyst, and a hydrocarbon-based solvent to obtain an olefin polymer,

    [Chemical Formula 1A]

    

    in Chemical Formula 1A,

    M is a transition metal of Group 4 in the periodic table;

    Y's are each independently -O-, -S-, -NR^1aa-, or -PR^2aa-; R^1aa and R^2aa are each independently hydrogen, (C1-C20)hydrocarbylene, (C1-C20)alkoxylene, (C6-C20)aryloxylene, or (C1-C20)alkylsilyl; and the hydrocarbylene, alkoxylene, aryloxylene, and alkylsilyl of Y may be substituted with halogen;

    L is a linker with 1 to 50 atoms excluding hydrogen; and

    R^1a to R^16a are each independently hydrogen, halogen, (C1-C30)heterohydrocarbyl, (C1-C30)hydrocarbyl, (C1-C30)alkoxy, (C6-C30)aryloxy, (C1-C30)alkylsilyl, (C1-C30)alkylboryl, (C1-C30)alkylamino, (C1-C30)diallylamino, (C1-C30)alkylphosphino, (C1-C30)alkylthio, or (C6-C30)arylthio, or represented by the following Chemical Formula 5A; the heterohydrocarbyl, hydrocarbyl, alkoxy, aryloxy, alkylsilyl, alkylboryl, alkylamino, alkylphosphino, alkylthio, and arylthio of R^1a to R^16a may be substituted with halogen, or adjacent substituents of R^1a to R^16a may be linked to each other to form an alicyclic ring or an aromatic ring; and the alicyclic ring and the aromatic ring may be substituted with one or more selected from the group consisting of (C1-C20)alkyl, (C1-C20)alkoxy, (C1-C20)alkoxy(C1-C20)alkyl, (C6-C20)aryl, (C6-C20)aryl(C1-C20)alkyl, (C1-C20)alkyl(C6-C20)aryl, (C1-C20)alkylsilyl, and (C6-C20)arylsilyl,

    [Chemical Formula 5A]

    

    in Chemical Formula 5A,

    R^35a to R^42a are each independently hydrogen, (C1-C30)alkyl, (C1-C30)alkylsilyl, (C1-C30)alkoxy, (C3-C30)cycloalkyl, (C6-C30)aryl, (C6-C30)aryl(C1-C30)alkyl, or (C1-C30)alkyl(C6-C30)aryl; and

    X's are each independently represented by the following Chemical Formula 2A,

    [Chemical Formula 2A]

    

    in Chemical Formula 2A,

    R^17a to R^24a are each independently hydrogen, (C1-C30)alkyl, (C2-C30)alkenyl, (C2-C30)alkynyl, (C1-C30)alkylsilyl, (C1-C30)alkoxy, (C3-C30)cycloalkyl, (C6-C30)aryl, (C6-C30)aryl(C1-C30)alkyl, or (C1-C30)alkyl(C6-C30)aryl; the alkyl, alkylsilyl, alkoxy, cycloalkyl, aryl, arylalkyl, and alkylaryl of R^17a to R^24a may be substituted with one or more selected from the group consisting of halogen, (C1-C10)alkyl, (C1-C10)alkylamino, (C1-C10)alkoxy, and (C1-C10)alkylsilyl; or adjacent substituents of R^17a to R^24a may be linked to (C3-C12)alkylene or (C3-C12)alkenylene with or without a fused ring to form an alicyclic ring or an aromatic ring; and the alicyclic ring or the aromatic ring may be substituted with one or more selected from the group consisting of (C1-C20)alkyl, (C1-C20)alkoxy, (C1-C20)alkoxy(C1-C20)alkyl, (C6-C20)aryl, (C6-C20)aryl(C1-C20)alkyl, (C1-C20)alkyl(C6-C20)aryl, (C1-C20)alkylsilyl, and (C6-C20)arylsilyl.
16. The method of claim 15, wherein the hydrocarbon-based solvent is:

    one or more non-aromatic hydrocarbon-based solvents selected from the group consisting of methylcyclohexane, cyclohexane, n-heptane, n-hexane, n-butane, isobutane, n-pentane, n-octane, isooctane, nonane, decane, and dodecane; or

    one or more aromatic hydrocarbon-based solvents selected from the group consisting of toluene, benzene, ethylbenzene, xylene, naphthalene, methylnaphthalene, anthracene, acenaphthene, and phenanthrene.
17. The method of claim 15, wherein the transition metal compound has a solubility in the hydrocarbon-based solvent at 25°C of 10 wt% or more.
18. The method of claim 15, wherein the cocatalyst is selected from an aluminum compound, a boron compound, or a mixture thereof.
19. The method of claim 18, wherein the boron compound is selected from compounds represented by the following Chemical Formula 3A to Chemical Formula 3D:

    [Chemical Formula 3A]

    B(R^25a)₃

    [Chemical Formula 3B]

    [R^26a]⁺[B(R^25a)₄]^-

    [Chemical Formula 3C]

    [R^27a _pZH]⁺[R^25a ₄]^-

    [Chemical Formula 3D]

    

    in Chemical Formula 3A to Chemical Formula 3D,

    B is boron;

    R^25a's are each independently phenyl substituted or unsubstituted with one or more substituents selected from the group consisting of fluorine, (C1-C20)alkyl, fluorine-substituted (C1-C20)alkyl, (C1-C20)alkoxy, and fluorine-substituted (C1-C20)alkoxy;

    R^26a is a (C5-C7) aromatic radical, a (C1-C20)alkyl(C6-C20)aryl radical, or a (C6-C20)aryl(C1-C20)alkyl radical;

    Z is nitrogen or phosphorus;

    R^27a's are each independently a (C1-C20)alkyl radical or a (C1-C10)alkyl-disubstituted anilinium radical;

    R^28a is (C5-C20)alkyl;

    R^29a is (C5-C20)aryl or (C1-C20)alkyl(C5-C20)aryl; and

    p is 2 or 3.
20. The method of claim 18, wherein the aluminum compound is selected from compounds represented by the following Chemical Formula 4A to Chemical Formula 4E:

    [Chemical Formula 4A]

    (-AlR^30a-O-)_m

    [Chemical Formula 4B]

    (R^31a)₂Al-(-OR^31a-)_q(-O-)Al(R^31a)₂

    [Chemical Formula 4C]

    (R^32a)_rAl(E)_3-r

    [Chemical Formula 4D]

    (R^33a)₂AlOR^34a

    [Chemical Formula 4E]

    R^33aAl(OR^34a)₂

    in Chemical Formula 4A to Chemical Formula 4E,

    R^30a and R^31a are each independently (C1-C20)alkyl;

    m and q are each independently an integer of 5 to 20;

    R^32a and R^33a are each independently (C1-C20)alkyl;

    E is hydrogen or halogen;

    r is an integer of 1 to 3; and

    R^34a is (C1-C20)alkyl or (C6-C30)aryl.
21. The method of claim 15, wherein the solution polymerization is performed at a temperature of 100°C to 200°C.