KR20030012098A - Multi-nuclear Transition Metal Catalysts and Polymerization Process Using the Same - Google Patents

Abstract

PURPOSE: Provided is a multi-nuclear transition metal catalyst, represented by a formula 1, which has interconnected transition metal compounds with salicylaldimine ligands. The catalyst is stable at high temperature and has such high activity that it is used in polymerizing a large amount of polyolefin while using a small amount of cocatalyst, and can produce high molecular weight polymers even at a higher polymerization temperature. CONSTITUTION: The preparation method of polymer comprises: using a multi-nuclear transition metal catalyst of the formula 1 as a main catalyst on a carrier; using unsaturated ethylene monomer, unsaturated styrene monomer or α,¥ø-diene monomer, each alone or in a mixture; and using a mixture of organometallic compound, non-covalent Louis acid or aluminum as a cocatalyst. The transition metal is selected from a group including titanium, zirconium and hafnium while it is supported by a carrier chosen from a group consisting of silica, alumina, magnesium chloride, zeolite, aluminum phosphate, polymer or organic carrier. The organometallic compound is either alkyl aluminum oxane or organo aluminum compound. In the formula 1, M is one of the transition metals of IVB-XIB group in the periodic table; R1-R9 which are individually same or different are hydrogen atom, halogen atom, hydrocarbon, functional group for heterocyclic compound and the groups containing oxygen, nitrogen, boron, sulfur, phosphorous, silicon, germanium or tin; G is C1-50 alkyl, cycloalkyl, aryl, alkylaryl group, the groups containing hetero atom or their combinations; X is independently same or different halogen atom, hydrocarbon, unsaturated hydrocarbon, hetero atom-containing group; l is an integer of 2-4; m is an integer of 0-3; n is an integer of 3-m; N---M bonds are general coordination and also include non-bonded coordination.

Description

Multi-nuclear Transition Metal Catalysts and Polymerization Process Using the Same}

Field of invention

The present invention relates to a transition metal compound catalyst that can be used for polymerization or copolymerization of ethylene, α-olefin, styrene monomers and a method for producing a polymer using the catalyst. More specifically, the present invention enables the production of copolymers of ethylene homopolymerization and ethylene / α-olefins and ethylene / styrene monomers using a multinuclear transition metal compound catalyst having two or more transition metal compounds connected to each other. In particular, it relates to a process for producing polymers having good activity, high molecular weight and good copolymerizability in the preparation of ethylene / α-olefins.

Background of the Invention

In general, polyolefins have excellent mechanical and chemical properties, and thus are widely used in various molded products. In recent years, polyolefins having various properties have been required as the demand for better physical properties for polyolefins increases.

In general, olefinic polymers are prepared by co-polymerization with radical polymerization or Ziegler-Natta Catalysts. By radical polymerization, LDPE polymers having various kinds of branches can be obtained. In the case of coordination polymerization with Ziegler-Natta catalysts, polymers of linear structure are mainly obtained.

As a Ziegler-Natta type catalyst for producing an ethylene homopolymer and a copolymer of ethylene / a-olefin, a titanium catalyst composed of a titanium compound and an organoaluminum compound, and a vanadium catalyst composed of a vanadium compound and an organoaluminum compound are widely known. have.

In addition, when a metallocene catalyst having a cyclopentadiene ligand and a cocatalyst are used, a polymer having high polymerization activity, a narrow molecular weight distribution, and a uniform copolymer distribution can be obtained. At this time, it is well known to use a MAO system or a boron system as a promoter.

Recently, various transition metal compounds having no cyclopentadiene ligand as catalysts for new olefin polymerization have been reported.

International Publication No. 962301 discloses a catalyst having a ligand of diimine structure, and International Publication Nos. 9842664 and 0056785 disclose hydroxy and imine groups as late transition metals. The catalyst coordinated to) is disclosed. In particular, the inventors of the above two patents reported results showing polymerization activity without using a promoter by using the Ni-based catalyst having the above ligand in Science Science 2000. (Science, 2000, 287, pp. 460-462)

Japanese Patent Laid-Open Nos. 2000-119315 and 2000-119316 disclose a novel transition metal compound catalyst by reacting two ligands coordinated with a hydroxyl group and an imine group with Zr metal or Ti metal. However, this catalyst has a problem in that stability with respect to high temperature and impurities decreases depending on the substituent, and the molecular weight of the polymer becomes very low as the polymerization temperature increases.

On the contrary, in order to overcome the above problems, the present inventors have developed a multi-nuclear transition metal compound catalyst having high stability against high temperature and impurities, and having a small decrease in activity and molecular weight with increasing polymerization temperature.

An object of the present invention is to provide a transition metal compound catalyst having high stability against impurities and high temperature in olefin polymerization.

Another object of the present invention is to provide a transition metal compound catalyst capable of producing a high molecular weight polymer even at a high polymerization temperature.

Another object of the present invention is to provide a high activity transition metal compound catalyst capable of producing a large amount of polyolefin polymer even with a small amount of promoter.

Another object of the present invention is to provide a method for efficiently preparing a copolymer of a polyethylene homopolymer and an α-olefin or styrene monomer using the catalyst.

The above and other objects of the present invention can be achieved by the present invention described below. Hereinafter, the content of the present invention will be described in detail.

Multinuclear Linked Transition Metal Compound Catalyst

The multi-nuclear transition metal catalyst of the present invention is composed of a structure containing 2-4 transition metals having a salicylaldimine ligand. The multinuclear transition metal compound catalyst according to the present invention is represented by the following formula (1).

[Formula 1]

Wherein M represents the Group IVB-XIB transition metal on the periodic table and is the same or different. Specifically, titanium (Ti), zirconium (Zr), hafnium (Hf), vanadium (V), niobium (Nb), tantalum (Ta), cobalt, rhodium, iridium, chromium, molybdenum, tungsten, manganese, Rhenium, iron and ruthenium. Of these, titanium, zirconium, hafnium, cobalt rhodium, vanadium, niobium, tantalum, and the like are preferred, and titanium, zirconium, and hafnium are most preferred.

R ¹ -R ⁹ is a hydrogen atom, a halogen atom, a hydrocarbon group, a heterocyclic compound functional group, an oxygen containing group, a nitrogen containing group, a boron-containing group, a sulfur-containing group, a phosphorus-containing group, a silicon-containing group, a germanium-containing group, or Represents tin-containing groups and is the same or different from one another; Two or more of them may be connected to each other to form a ring.

G includes an alkyl group having 1 to ₅₀ carbon atoms, a cycloalkyl group, an aryl group, an alkylaryl group, a hetero atom-containing group, and a combination thereof.

X is a halogen atom, a hydrocarbon group, an unsaturated hydrocarbon group, a hetero atom-containing group, the same as or different from each other, and may form a ring with each other.

L is an integer from 2-4; m is an integer from 0-3; n is an integer of 3-m.

The above N --- M bond means a general coordination, but in the present invention also includes a simple coordination without binding.

The salicylaldimine ligand of the present invention can be synthesized using the procedure disclosed in International Publication No. 98/42664 and in Organometallics (1998, 17, 3149-3151).

The transition metal compound of the present invention may be used in a supported form, and as the support, silica, alumina, magnesium chloride, zeolite, aluminum phosphate, zirconia, polymer, and other organic carriers may be used. .

Promoter

An organometallic compound may be used as a cocatalyst together with the transition metal compound of the present invention, or a mixture of uncoordinated Lewis acid and alkylaluminum may be used.

The organometallic compound may be an alkyl aluminum oxane or an organoaluminum compound. Representative examples of the alkylaluminum oxane include methylaluminoxane (MAO) and modified methylaluminoxane (MAMAO). The organoaluminum compound has a unit represented by the following formula (2), and these include a chain-shaped aluminum oxane represented by the following formula (3) and a cyclic aluminum oxane represented by the following formula (4).

Formula 2

Formula 3

Formula 4

In the above formula, R is an alkyl group of C _1-6 , m and n are integers of 0-100.

As the cocatalyst, a mixture of aluminum oxanes of different kinds may be used as necessary, and aluminum oxane and alkyl aluminum, for example, trimethyl aluminum, triethyl aluminum, triisobutyl aluminum, dimethyl aluminum chloride, etc. may be mixed. Can be.

In the ratio of the metallocene catalyst component and the organometallic compound component as a promoter according to the present invention, the molar ratio of aluminum in the organometallic compound component to the Group 4 transition metal on the periodic table in the metallocene catalyst component, That is, the molar ratio of aluminum to transition metal (eg, titanium, zirconium, hafnium) is in the range of 1: 1 to 10 ⁶ : 1, preferably in the range of 10: 1 to 10 ⁴ : 1.

The non-coordinating Lewis acids in the mixture of non-coordinating Lewis acids and alkylaluminum used as cocatalysts are N, N-dimethyl aniline tetrakis (pentafluorophenyl) borate, triphenyl carbenium tetrakis (pentafluorophenyl) borate, ferro Cerium tetrakis (pentafluorophenyl) borate, or tris (pentafluorophenyl) borate, and alkylaluminum is trimethyl aluminum, triethyl aluminum, diethylaluminum chloride, dimethylaluminum chloride, triisobutyl aluminum, di Isobutylaluminum chloride, tri (n-butyl) aluminum, tri (n-propyl) aluminum, or triisopropylaluminum.

In the catalyst system composed of the metallocene catalyst and the cocatalyst of the present invention, the molar ratio of the non-coordinated Lewis acid: transition metal is preferably in the range of 0.1: 1 to 20: 1, most preferably 1: 1. If the ratio is less than 0.01, the metal complex cannot be effectively activated, and if it exceeds 100, it is not economical.

The metal complex and the promoter may be mixed and prepared outside the polymerization reactor, or may be mixed in the polymerization reactor during the polymerization.

Monomer

The ethylene monomer polymerized using the catalyst system according to the present invention is ethylene, an unsaturated ethylenic monomer having a substituent, or α, ω-diene, and the styrene monomer is an styrene-based unsaturated styrene monomer having a substituent. The monomer and the styrene monomer can be copolymerized alone or in combination of two or more. The ethylenically unsaturated monomer is an olefin and includes ethylene, propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-heptene, 1-octene, and the like. Examples of the olefin include cyclobutene, cyclopentene, cyclohexene, 3-methylcyclopentene, 3-methylcyclohexene, norbornene and the like.

The α, ω-diene refers to non-conjugated diene, 1,4-pentadiene, 1,5-hexadiene, 1,6-heptadiene, 1,7-octadiene, 1 , 8-nonadiene, 1,9-decadiene, 1,4-hexadiene, dicyclopentadiene, 5-ethylidene-2-norbornene, 5-vinyl norbornene, methyl hexadiene and the like are used and 0-25 It may be present in the copolymer in a weight ratio of about%.

Polymerization condition

In the present invention, the monomer and solvent (if a solvent is used) prior to polymerization can be purified by vacuum distillation or by contact with alumina, silica or molecular sieve. In addition, impurities can be removed by using a trialkyl aluminum compound, an alkali metal, a metal alloy (particularly Na / K), or the like.

When using an organometallic compound as a cocatalyst, the molar ratio of aluminum to transition metal (e.g. titanium, zirconium, hafnium) is in the range of 1: 1 to 10 ⁶ : 1, preferably in the range of 10: 1 to 10 ⁴ : 1 It is good to be.

When using a mixture of uncoordinated Lewis acid and alkylaluminum as a cocatalyst, the molar ratio of uncoordinated Lewis acid: transition metal is preferably in the range of 0.1: 1 to 20: 1, most preferably 1: 1.

The polymerization temperature for producing a polyolefin using the transition metal compound of the present invention is preferably 0 to 140 ° C, more preferably in the range of 20-100 ° C. When the polymerization temperature is lower than -78 ° C, it is industrially disadvantageous, and when the polymerization temperature is higher than 200 ° C, decomposition of the metal complex occurs, which is not suitable.

The weight average molecular weight (Mw) of the ethylene homopolymer or ethylene / α-olefin copolymer prepared using the catalyst system of the present invention is preferably 13,000 or more, more preferably 20,000 or more, and most preferably 30,000 or more. Have In addition, the melt index (ASTM D-1238 Method A, Condition E) of ethylene homopolymers or ethylene / α-olefin copolymers prepared using the catalyst system of the present invention is 0.001-1000, preferably 0.01-100, Preferably it is 0.1-30.

The invention can be better understood by the following examples, which are intended for the purpose of illustration of the invention and are not intended to limit the scope of protection defined by the appended claims.

Example

The transition metal catalyst of the present invention is embodied in the following examples, and the structure of the obtained polymer or copolymer is 40 to 50 mg of a polymer sample containing about 5 ml of hot trichlorobenzene and benzene-deuterium 4: 1 mixed solvent. It was dissolved in a 5 mm NMR tube and analyzed by 100 MHz ¹³ C NMR spectrum. The salicylaldimine ligand of the present invention was synthesized using the procedure disclosed in WO 98/42664 and Organometallics 1998, 17, 3149-3151.

Example 1-4 Preparation of Catalyst

Example 1 Preparation of Catalyst 1

(1) Synthesis of Ligand 1

In a 250 mL flask, 3-t-butyl-2-hydroxybenzaldehyde (2.5 g, 14 mmol) was dissolved in methanol / THF mixed solution (100 mL) and stirred at room temperature. To this, a, a'-bis (4-aminophenyl) -1,4-diisopropelbenzene (2.29 g, 6.64 mmol) was slowly injected into the syringe, and then a small amount of HCHO was added and stirred. After about 10 hours, the solvent was removed in vacuo and purified by column chromatography (silica gel) to give the product as a yellow solid as 75% product: ¹ H NMR (300MHz, CDCl ₃ ), ¹³ C NMR (75 MHz, CDCl ₃ )

Ligand 1

(2) Preparation of Zr Compound Solution

In the nitrogen-substituted 100mL flask, ligand 1 (1.39g, 2.09mmol) prepared above was dissolved in 50mL of THF and stirred at -78 ° C. 4.2 mmol of t-BuLi (1.7 M, ether solution) was slowly injected into the syringe, and the reaction mixture was heated to room temperature for 3 hours. 0.975 g (4.18 mmol) of ZrCl ₄ was mixed with 50 mL of THF in a nitrogen-substituted 250 mL flask and stirred at -78 ° C. The lithiated salt solution of the 100 mL flask was slowly added dropwise under a nitrogen atmosphere using a cannular into a 250 mL flask. After the completion of the injection, the reaction product was heated to room temperature and reacted for 10 hours or more to prepare a Zr compound solution.

(3) Synthesis of Catalyst

In another nitrogen-substituted 100 mL flask, 1.23 g (4.18 mmol) of 2-t-butyl-6- (2-isopropylphenyl) iminomethylphenol (2-tert-butyl-6- (2-isopropylphenyl) -iminomethylphenol ) Was dissolved in 50 mL of THF, stirred at -78 ° C, 4.18 mmol of t-butyllithium was injected into the syringe, and then stirred at room temperature for 3 hours to prepare Reactant 1.

The Zr compound solution of Ligand 1 prepared above was cooled to −78 ° C., and then the reactant 1 was slowly injected into the cannular, heated to room temperature, and stirred for 13 hours. The solvent was removed under vacuum, 150 mL of toluene was injected and the precipitated LiCl was filtered off. The toluene filtrate was concentrated in vacuo and recrystallized in ether / pentane mixed solvent to give a pale yellow solid catalyst with a yield of 49%: ¹ H NMR (300 MHz, CDCl ₃ ), ¹³ C NMR (75 MHz, CDCl ₃ )

Example 2 Preparation of Catalyst 2

(1) Synthesis of Ligand 2

3-t-butyl-2-hydroxybenzaldehyde (2.60 g, 14.6 mmol) was dissolved in methanol (100 mL) in a 250 mL flask and stirred at room temperature. 4,4'-ethylenedi-m-toluidine (4,4'-ethylenedi-m-toluidine, 1.53 g, 6.90 mmol) was slowly injected into the syringe, and then a small amount of HCHO was added and stirred. After about 10 hours, the solvent was removed in vacuo and purified by column chromatography (silica gel) to give the product as a yellow solid as 82% product: ¹ H NMR (300MHz, CDCl ₃ ), ¹³ C NMR (75MHz, CDCl ₃ )

Ligand 2

(2) Preparation of Zr Compound Solution

It was prepared in the same manner as in Example 1 except for using Ligand 2 (1.10 g, 2.09 mmol) prepared from the above.

(3) Synthesis of Catalyst

In another nitrogen-substituted 100 mL flask, 1.32 g (4.18 mmol) of 2-t-butyl-6-cyclohexyliminomethylphenol (2-tert-butyl-6-cyclohexyliminomethylphenol) was dissolved in 50 mL of THF at -78 ° C. While stirring, 4.18 mmol of t-butyllithium was injected into the syringe, followed by stirring at room temperature for 3 hours to prepare Reactant 2.

After cooling the Zr compound solution of Ligand 2 to −78 ° C., Reactant 2 prepared above was slowly injected into the cannular, heated to room temperature, and stirred for 13 hours. The solvent was removed under vacuum, 150 mL of toluene was injected and the precipitated LiCl was filtered off. The toluene filtrate was concentrated in vacuo and recrystallized in ether / pentane mixed solvent to give a pale yellow solid catalyst with a yield of 48%: ¹ H NMR (300 MHz, CDCl ₃ ), ¹³ C NMR (75 MHz, CDCl ₃ )

Example 3 Preparation of Catalyst 3

(1) Preparation of Ti Compound Solution

Ligand 1 (1.09 g, 1.64 mmol) prepared in Example 1 was dissolved in 50 mL of THF in a nitrogen-substituted 100 mL flask and stirred at -78 ° C. 3.5 mmol t-BuLi (1.7M, ether solution) was slowly injected into the syringe, and the reaction mixture was heated to room temperature for 3 hours. 1.10 g (3.28 mmol) of TiCl ₄ .2THF was mixed with 50 mL of THF in a 250 mL nitrogen-substituted flask, followed by stirring at -78 ° C. The lithiated salt solution of the 100 mL flask was slowly added dropwise under a nitrogen atmosphere using a cannular into a 250 mL flask. After the completion of the injection, the reaction was heated to room temperature and reacted for at least 10 hours.

(2) Synthesis of Catalyst

In another nitrogen-substituted 100 mL flask, 0.96 g (3.28 mmol) of 2-t-butyl-6- (2-isopropylphenyl) iminomethylphenol (2-tert-butyl-6- (2-isopropylphenyl) -iminomethylphenol ) Was dissolved in 50 mL of THF, and stirred at -78 ° C. 3.50 mmol of t-butyllithium was injected into a syringe, followed by stirring at room temperature for 3 hours to prepare Reactant 3.

After cooling the Ti compound solution of Ligand 1 to -78 ° C, Reactant 3 prepared above was slowly injected into the cannular, heated to room temperature, and stirred for 13 hours. The solvent was removed under vacuum, 150 mL of toluene was injected and the precipitated LiCl was filtered off. The toluene filtrate was concentrated in vacuo and recrystallized in ether / pentane mixed solvent to give a light reddish brown solid catalyst 3 with a yield of 50%: ¹ H NMR (300 MHz, CDCl ₃ ), ¹³ C NMR (75 MHz, CDCl ₃ )

Example 4 Preparation of Catalyst 4

(1) Preparation of Ti Compound Solution

Ligand 2 (1.98g, 3.73mmol) prepared in Example 2 was dissolved in 50mL of THF in a nitrogen-substituted 100mL flask and stirred at -78 ° C. Here, 8.1 mmol of t-BuLi (1.7 M, ether solution) was slowly injected into the syringe, and the reaction mixture was heated to room temperature for 3 hours. 2.49 g (7.46 mmol) of TiCl ₄ .2THF was mixed with 50 mL of THF in a 250 mL nitrogen-substituted flask, followed by stirring at -78 ° C. The lithiated salt solution of the 100 mL flask was slowly added dropwise under a nitrogen atmosphere using a cannular into a 250 mL flask. After the completion of the injection, the reaction was heated to room temperature and reacted for at least 10 hours.

(2) Synthesis of Catalyst

In another nitrogen-substituted 100 mL flask, 2.24 g (7.46 mmol) of 2-t-butyl-6-cyclohexyliminomethylphenol (2-tert-butyl-6-cyclohexyliminomethylphenol) was dissolved in 50 mL of THF at -78 ° C. While stirring, 7.46 mmol of t-butyllithium was injected into the syringe, followed by stirring at room temperature for 3 hours to prepare Reactant 4.

The Ti compound solution of Ligand 2 was cooled to −78 ° C., and then reactant 4 was slowly injected into the cannular, heated to room temperature, and stirred for 13 hours. The solvent was removed under vacuum, 150 mL of toluene was injected and the precipitated LiCl was filtered off. The toluene filtrate was concentrated in vacuo and recrystallized in ether / pentane mixed solvent to give a light brown solid catalyst 4 in 38% yield: ¹ H NMR (300MHz, CDCl ₃ ), ¹³ C NMR (75MHz, CDCl ₃ )

Comparative Example 1-5 Synthesis of Comparative Catalyst

Comparative Example 1 [tBu-N-Si (Me) ₂ -Cp (Me) ₄ ] TiCl ₂

[TBu-N-Si (Me) ₂ -Cp (Me) ₄ ] -TiCl ₂ , known as Constrained Geometry Catalyst (CGC), was synthesized using the method disclosed in EP 416,815 A2.

Comparative Example 2-5

A catalyst from Mitsui (formula below) with two Salicylaldimines was synthesized using the method disclosed in WO 00/78828 A1.

Comparative Example 2: [2-tBu-C ₆ H ₃ (OH) -CH = N- (2-iPr) C ₆ H ₄ ] ₂ ZrCl ₂ ;

Comparative Example 3: [2-tBu-C ₆ H ₃ (OH) -CH = NC ₆ H ₁₁ ] ₂ ZrCl ₂ ;

Comparative Example 4: [2-tBu-C ₆ H ₃ (OH) -CH = N- (2-iPr) C ₆ H ₄ ] ₂ TiCl ₂ ;

Comparative Example 5: [2-tBu-C ₆ H ₃ (OH) -CH = NC ₆ H ₁₁ ] ₂ TiCl ₂

Example 5-14: Ethylene Homopolymerization

Using a jacket-heating 2 L glass autoclave equipped with a magnetic stirrer, vacuum and nitrogen substitution were repeated to completely replace the inside with nitrogen, followed by polymerization. Cooling was selected by installing a cooling coil inside the reactor to flow the cooling water. Solvents such as hexane and toluene were used by adding Na and distilling. The solvents were contacted with molecular sieve, alumina, silica or the like and stored under nitrogen. Hexane (400 mL) and MAO were added to the high pressure reactor substituted with nitrogen, and the polymerization temperature was maintained while stirring. At the same time as injecting the catalyst prepared in Example 1-4 and Comparative Example 1-5, ethylene at 4 atmospheres was injected to initiate polymerization. At this time, the consumption amount of ethylene, the calorific value and the stirring state were observed. After a certain period of time, the ethylene gas was depressurized, a hydrochloric acid / methanol solution was added to stop / wash the reaction, and then a polyethylene powder having a narrow molecular weight distribution was recovered. Among them, the samples with high molecular weight, which cannot measure Mw by high temperature GPC, measure the intrinsic viscosity in the decalin solution at 135 ° C and use the formula ([η] = 6.2 × 10 ^-4 ) of J. Polymer Sci. (1959, 36, 91) Mv (viscosity mean molecular weight) was calculated using Mv ^0.7 ). The polymerization result of polyethylene obtained by drying under reduced pressure is shown in Table 1.

Example 5-7 uses 10 μmol of the catalyst prepared in Example 1, and the polymerization temperature is performed at 30 ° C., 50 ° C. and 70 ° C., respectively.

Example 8-10 uses 10 μmol of the catalyst prepared in Example 2, and the polymerization temperature is performed at 30 ° C., 50 ° C. and 70 ° C., respectively.

Examples 11-13 use 20 μmol of the catalyst prepared in Example 3, and perform polymerization temperatures at 30 ° C., 50 ° C., and 70 ° C., respectively.

Example 14 uses 20 μmol of the catalyst prepared in Example 4, and performs a polymerization at 30 ° C.

In Comparative Example 6, 20 µmol of the catalyst prepared in Comparative Example 1 was used, and the polymerization temperature was performed at 70 ° C.

In Comparative Example 7-8, 10 μmol of the catalyst prepared in Comparative Example 2 was used, and the polymerization temperature was performed at 70 ° C. and 30 ° C., respectively.

In Comparative Example 9-11, 10 µmol of the catalyst prepared in Comparative Example 3 was used, and polymerization temperatures were performed at 30 ° C, 50 ° C, and 70 ° C, respectively.

In Comparative Example 12-14, 20 µmol of the catalyst prepared in Comparative Example 4 was used, and polymerization temperatures were performed at 30 ° C, 50 ° C, and 70 ° C, respectively.

In Comparative Examples 15-17, 20 µmol of the catalyst prepared in Comparative Example 5 was used, and polymerization temperatures were performed at 30 ° C, 50 ° C, and 70 ° C, respectively.

Polymerization condition: MAO / Ti = 500, Polymerization time: 60 minutes

In the above, Comparative Example 2: [2-tBu-C ₆ H ₃ (OH) -CH = N- (2-iPr) C ₆ H ₄ ] ₂ ZrCl ₂ ;

Comparative Example 3: [2-tBu-C ₆ H ₃ (OH) -CH = NC ₆ H ₁₁ ] ₂ ZrCl ₂ ;

Comparative Example 4: [2-tBu-C ₆ H ₃ (OH) -CH = N- (2-iPr) C ₆ H ₄ ] ₂ TiCl ₂ ;

Comparative Example 5: [2-tBu-C ₆ H ₃ (OH) -CH = NC ₆ H ₁₁ ] ₂ TiCl ₂ was used.

In the above results, in the case of a catalyst having a ligand synthesized using salicylic aldehyde and an aromatic amine, the transition metal compound catalysts (Examples 1 and 3) connected by dinuclei are mononuclear transition metal compound catalysts (Comparative Example 2 It was found that the high activity and high molecular weight were provided at each polymerization temperature compared to Comparative Example 4).

In addition, in the case of a catalyst having a ligand synthesized using salicylate and aliphatic amine, it was confirmed that the catalysts of Examples 2 and 4 produced polymers having higher polymerization activity and higher molecular weight than those of Comparative Examples 3 and 5, respectively. .

As described above, the transition metal compound catalyst linked to the nucleus in the polymerization using a catalyst having a ligand having a similar structure showed a higher level of polymerization activity under the same conditions as the mononuclear transition metal compound catalyst. In the case of the connected transition metal compound catalyst, it has been found to have high stability and high activity even at high polymerization temperature and to produce high molecular weight polyethylene. In particular, it was confirmed that the transition metal compound catalyst connected by the binucle of Example 1 expresses three times or more higher activity than the catalyst (CGC) of Comparative Example 1, which is widely known as a catalyst for polyethylene polymerization.

Example 15-17 Ethylene Homopolymerization at Low Catalyst Concentration

In order to observe the finer difference in polymerization activity, hexane (400 mL) and MAO were added to a 2 L glass high pressure reactor, and the polymerization temperature was maintained while stirring. At the same time as injecting the catalyst of Example 1 and the catalyst of Comparative Example 2 each containing a certain amount of metal (0.1-5 μmol), ethylene at 4 atmospheres was injected to initiate polymerization. At this time, the consumption amount of ethylene, the calorific value and the stirring state were observed. After about 10 minutes, the ethylene gas was depressurized and the reaction was stopped / washed by adding hydrochloric acid / methanol solution, and then powdered polyethylene was recovered. The polymerization result of polyethylene obtained by drying under reduced pressure is shown in Table 2.

Polymerization condition: MAO = 2.5 mmol, Polymerization time: 10 minutes

In the above results, it was found that the transition metal compound catalyst of the present invention connected by multinucleus was superior in yield and catalytic activity compared to the mononuclear catalyst, and a high molecular weight polyethylene was obtained.

Example 18 Ethylene / 1-Octene Copolymerization

Hexane (1000 mL), 1-octene (50 mL), and MAO (5 mmol Al) were added to a 2 L metal high pressure reactor, and the mixture was heated to 70 ° C. At the same time as injecting the catalyst of Example 1 of 5 µmol Zr, 10 atm of ethylene was injected to initiate polymerization. The consumption of ethylene, the calorific value and the stirring state were observed. After 30 minutes, the ethylene gas was released and the reaction was stopped / washed by adding hydrochloric acid / methanol solution, and then the copolymer was recovered. It dried under reduced pressure and obtained 59g (23,600Kg / molZr * hr) ethylene / 1-octene copolymer. The copolymer obtained above contained 7.4 mol% of 1-octene as a result of ¹³ C NMR analysis, and had a melting point of 99 ° C.

The multinuclear transition metal compound catalyst of the present invention has excellent stability against impurities and high temperatures in the preparation of ethylene homopolymerization and copolymers with higher α-olefins, and a large amount of polyolefin polymer even with a small amount of promoter. It has a high activity to produce a, has the effect of providing a transition metal compound catalyst capable of producing a high molecular weight polymer even at a high polymerization temperature.

Simple modifications or changes of the present invention can be easily carried out by those skilled in the art, and all such modifications or changes can be seen to be included in the scope of the present invention.

Claims (12)

Ligand binding to the central metal of the transition metal compound is connected to each other comprising two to four transition metals in a molecule represented by the following formula 1, multinuclear linked transition metal compound catalyst: [Formula 1] Wherein M represents the Group IVB-XIB transition metal on the periodic table and is the same or different from each other; R ¹ -R ⁹ is a hydrogen atom, a halogen atom, a hydrocarbon group, a heterocyclic compound functional group, an oxygen-containing group, a nitrogen-containing group, a boron-containing group, a sulfur-containing group, a phosphorus-containing group, a silicon-containing group, a germanium-containing group, or tin It is an containing group, two or more of which may be connected to each other to form a ring, wherein R ¹ -R ⁹ may be the same or different from each other; G includes an alkyl group, a cycloalkyl group, an aryl group, an alkylaryl group, a hetero atom containing group, or a combination thereof, which is C _1-50 ; X is a halogen atom, a hydrocarbon group, an unsaturated hydrocarbon group, or a heteroatom-containing group, at least two of which may be linked to each other to form a ring, wherein X may be the same as or different from each other; L is an integer from 2-4; m is an integer from 0-3; n is an integer of 3-m; The above N --- M bond also includes simple coordination with or without general coordination. The multinuclear connected transition metal compound catalyst according to claim 1, wherein the transition metal is titanium, zirconium or hafnium. 2. The multinuclear connected transition metal compound catalyst according to claim 1, wherein the transition metal compound catalyst is supported on a carrier. The multinucleated linkage transition according to claim 3, wherein the carrier is selected from the group consisting of silica, alumina, magnesium chloride, zeolite, aluminum phosphate, zirconia, polymer, and organic carrier. Metal compound catalyst. Using the multinuclear linked transition metal compound catalyst according to any one of claims 1 to 4 as a main catalyst; Unsaturated ethylenic monomers, unsaturated styrene type monomers, or α, ω-diene monomers are used alone or in combination; And organometallic compounds or mixtures of non-coordinating Lewis acids with alkylaluminum as cocatalysts. The method for producing a polyolefin and a styrene homopolymer or a copolymer thereof according to claim 5, wherein the organometallic compound is an alkylaluminum oxane or an organoaluminum compound. 6. The method according to claim 5, wherein the alkyl aluminum oxane is methyl aluminum oxane (MAO) or modified methyl aluminum oxane (MMAO). 7. The polyolefin and styrene homopolymer or its compound according to claim 6, wherein the organoaluminum compound has a unit represented by the following formula (2) and is a chain or cyclic aluminum oxane represented by the following formula (3) or (4). Preparation of Copolymers: Formula 2 Formula 3 Formula 4 Wherein R is a C _1-6 alkyl group and m and n are integers from 0-100. 6. The non-coordinating Lewis acid of claim 5, wherein the non-coordinating Lewis acid is N, N-dimethyl aniline tetrakis (pentafluorophenyl) borate, triphenyl carbenium tetrakis (pentafluorophenyl) borate, ferrocerium tetrakis (pentafluoro Rophenyl) borate, and tris (pentafluorophenyl) borate; The alkyl aluminum is trimethyl aluminum, triethyl aluminum, diethyl aluminum chloride, dimethyl aluminum chloride, triisobutyl aluminum, diisobutyl aluminum chloride, tri (n-butyl) aluminum, tri (n-propyl) aluminum, and triiso A method for producing a polyolefin and styrene homopolymer or a copolymer thereof, which is selected from the group consisting of propyl aluminum. The polyolefin and styrene homopolymer or air thereof according to claim 5, wherein the molar ratio of aluminum in the organometallic compound and the transition metal in the metallocene catalyst component is from 1: 1 to 10 ⁶ : 1. Process for the preparation of coalescing. The method for producing a polyolefin and styrene homopolymer or copolymer thereof according to claim 5, wherein the molar ratio of the non-coordinated Lewis acid and the transition metal in the metallocene catalyst is 0.1: 1 to 20: 1. A homopolymer or copolymer thereof of ethylene, α-olefin and styrene monomers prepared by the process according to any one of claims 5 to 11.