JP2008063300A - Cationic complex, polymerization catalyst containing the same, polymerization method using the polymerization catalyst and polymer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a new catalyst which can be synthesized and isolated with ease, has excellent polymerization activities, and forms an olefin polymer having excellent characteristics. <P>SOLUTION: The cationic complex is represented by general formula (I) (wherein, Ln is the group 3 transition metal atom in the periodic table; X is a halogen atom; R<SP>1</SP>and R<SP>2</SP>are each a hydrogen atom, a halogen atom or a 1-12C hydrocarbon group in which at least one carbon atom may be substituted with a nitrogen, phosphorus, oxygen, sulfur or silicon atom; Z is a solvent molecule; and p is an integer of 1 or 2). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a novel cationic complex, a polymerization catalyst containing the same, a polymerization method using the polymerization catalyst, and a polymer obtained thereby. More specifically, a cation complex in which a specific ligand is coordinated to a group 3 transition metal atom in the periodic table, a polymerization catalyst containing the same, a polymerization method using the polymerization catalyst, and a weight obtained thereby. Regarding coalescence.

As the olefin polymerization catalyst, a so-called Ziegler-Natta catalyst or metallocene catalyst comprising a transition metal compound such as titanium and an organoaluminum compound is widely known.
On the other hand, as a catalyst for polymerizing conjugated dienes, catalysts composed of transition metal compounds such as titanium, vanadium, cobalt, nickel and organoaluminum compounds and organolithium catalysts are known, and these catalysts are used. Polybutadiene and polyisoprene are produced industrially.

However, recently, physical properties required for olefin polymers and conjugated diene polymers have been diversified, and accordingly, catalysts that can control molecular weight distribution, steric structure, copolymerizability and the like more precisely are demanded.
In order to meet such demands, studies have been conducted on the use of rare earth metal complex compounds as polymerization catalysts for olefins and conjugated dienes. Since this type of complex functions as a catalyst having features such as high activity and high stereoselectivity, its attention is increasing.
For example, a catalyst composed of (C ₅ Me ₄ SiMe ₃ ) Sc (CH ₂ SiMe ₃ ) ₂ (THF) / [Ph ₃ C] [B (C ₆ F ₅ ) ₄ ] is a stereospecific compound of styrene and ethylene. It has been reported that it can be applied to syndiotactic copolymerization, alternating copolymerization of ethylene and norbornene, and ethylene-dicyclopentadiene-styrene terpolymerization (Non-Patent Documents 1 to 3). However, there is no report that this catalyst can be applied to the polymerization of conjugated dienes.

"Journal of American Chemical Society", 2004, vol. 126, pp 13910 “Angevante Chemie International Edition”, 2005, Vol. 44, pp962 (Angewandte Chemie International Edition) “Macromolecules”, 2005, Vol. 38, pp6767.

On the other hand, Gd (III) / Al (III) complex represented by the general formula: Cp ^R ₂ Gd (μ-Me) ₂ AlMe ₂ , Cp ^R ₂ GdN (SiMe ₃ ) ₂ and C ₅ H ₅ GdN [(SiMe ₃ ) ₂ ] ₂ [wherein Cp ^R = C ₅ Me ₄ H, C ₅ Me ₅ , or C ₅ Me ₄ Et], an example of polymerization of 1,3-butadiene by a Gd (III) complex has been reported. (Non-Patent Document 4).
Patent Document 1 reports the polymerization of a conjugated diene by a metallocene-type cation complex of a gadolinium compound represented by the general formula: R _a GdX _b .
However, these complexes are very difficult to synthesize and isolate and are problematic for application in industrial production.

"Polymer Preprints Japan" (Polymer Preprints, Japan), Vol. 54, No. 2, pp 2520 Japanese Patent Laid-Open No. 2004-238637

Accordingly, an object of the present invention is to provide a novel catalyst that is easy to synthesize and isolate, has excellent polymerization activity, and provides an olefin polymer having excellent characteristics.
As a result of diligent research to achieve the above object, the present inventors have found a novel cation complex having a transition metal atom of Group 3 of the periodic table as a central atom, and the above problem can be achieved by using this complex. Based on this finding, the present inventors have completed the present invention.

〔但し、一般式（Ｉ）中、Ｌｎは、周期表第３族遷移金属原子である。Ｘは、ハロゲン原子である。Ｒ^１及びＲ^２は、それぞれ、水素原子、ハロゲン原子又は炭素数１〜１２の炭化水素基であり、これらの炭化水素基は、その少なくとも１つの炭素原子を窒素、リン、酸素、硫黄又はケイ素原子で置き換えたものであってもよい。Ｚは溶媒分子である。ｐは１又は２の整数を示す。〕 Thus, according to the present invention, there is provided a cation complex represented by the general formula (I).

[However, in general formula (I), Ln is a periodic table group 3 transition metal atom. X is a halogen atom. R ¹ and R ² are each a hydrogen atom, a halogen atom or a hydrocarbon group having 1 to 12 carbon atoms, and these hydrocarbon groups have at least one carbon atom as nitrogen, phosphorus, oxygen, sulfur or silicon. It may be replaced with an atom. Z is a solvent molecule. p represents an integer of 1 or 2. ]

Moreover, according to this invention, the catalyst for olefin polymerization formed by containing the said cation complex is provided. This olefin polymerization catalyst preferably further comprises at least one of an organoaluminum compound and an organoboron compound.
The olefin polymerization catalyst of the present invention can be suitably applied to conjugated dienes and ethylene.

The present invention also provides an olefin polymerization method using the olefin polymerization catalyst of the present invention.
The olefin polymerization method of the present invention can be suitably applied to conjugated dienes and ethylene.
Furthermore, according to this invention, the olefin polymer obtained by the said polymerization method is provided.
The weight average molecular weight of the polymer obtained by the polymerization method of the present invention measured by gel permeation chromatography (GPC) is preferably 1,000 to 1,000,000.

  The complex of the present invention can be easily synthesized and isolated, and an olefin polymer can be obtained by polymerizing an olefin using a polymerization catalyst or a polymerization catalyst composition containing the complex. When a conjugated diene is used as the olefin, the resulting conjugated diene polymer has a high cis structure.

一般式（Ｉ）中、Ｌｎは、周期表第３族遷移金属原子である。具体的には、スカンジウム、イットリウムのほか、ネオジム、サマリウム、ユーロピウム、ガドリニウム、テルビウム、ディスプロシウム等のランタノイド原子を挙げることができる。これらのうち、スカンジウム、イットリウム及びガドリニウムが好ましい。
Ｘは、塩素原子、臭素原子、沃素原子等のハロゲン原子である。
Ｒ^１及びＲ^２は、それぞれ、水素原子、ハロゲン原子又は炭素数１〜１２の炭化水素基であり、これらの炭化水素基は、その少なくとも１つの炭素原子を窒素、リン、酸素、硫黄又はケイ素原子で置き換えたものであってもよい。
Ｚは溶媒分子である。
ｐは１又は２の整数を示す。 The cation complex of the present invention is represented by the general formula (I).

In general formula (I), Ln is a periodic table group 3 transition metal atom. Specific examples include lanthanoid atoms such as neodymium, samarium, europium, gadolinium, terbium and dysprosium in addition to scandium and yttrium. Of these, scandium, yttrium and gadolinium are preferred.
X is a halogen atom such as a chlorine atom, a bromine atom or an iodine atom.
R ¹ and R ² are each a hydrogen atom, a halogen atom or a hydrocarbon group having 1 to 12 carbon atoms, and these hydrocarbon groups have at least one carbon atom as nitrogen, phosphorus, oxygen, sulfur or silicon. It may be replaced with an atom.
Z is a solvent molecule.
p represents an integer of 1 or 2.

R ¹ and R ² are each a hydrogen atom, a halogen atom, or a hydrocarbon group having 1 to 12 carbon atoms. The hydrocarbon group having 1 to 12 carbon atoms is preferably an alkyl group having 1 to 12 carbon atoms or an aralkyl group, an alkenyl group having 2 to 12 carbon atoms, or an aryl group or alkaryl group having 6 to 12 carbon atoms. .

  Specific examples of the hydrocarbon group having 1 to 12 carbon atoms include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, t-butyl group, pentyl group, C1-C12 alkyl groups such as hexyl and octyl groups; C2-C12 alkenyl groups such as vinyl groups; C1-C12 aralkyl groups such as benzyl groups; Carbons such as phenyl groups and naphthyl groups An aryl group having 6 to 12 carbon atoms; an alkaryl group having 7 to 12 carbon atoms such as a tolyl group and a xylyl group;

The hydrocarbon group having 1 to 12 carbon atoms may have a halogen atom or a functional group having a nitrogen atom, an oxygen atom, a silicon atom, a sulfur atom or a phosphorus atom as a substituent. Examples of such functional groups include, in addition to halogen atoms, amino groups, cyano groups, hydroxyl groups, alkoxy groups, carboxyl groups, ester groups (alkoxycarbonyl groups), silyl groups, silylamide groups, thiol groups, sulfone groups, phosphoryl groups. Groups and the like.
Specific examples of the hydrocarbon group having 1 to 12 carbon atoms having such a substituent include a chlorophenyl group, a trifluoromethyl group, and a methoxyethyl group.

The hydrocarbon group having 1 to 12 carbon atoms constituting R ¹ and R ² may be one in which at least one of the carbon atoms is replaced with nitrogen, phosphorus, oxygen, sulfur or silicon atom. Examples thereof include a methylsilyl group, a dimethylsilyl group, a trimethylsilyl group, a triethylsilyl group, and a bistrimethylsilylamide group.
Preferable specific examples of R ¹ and R ² include a bistrimethylsilylamide group.

The solvent molecule represented by Z is not particularly limited, and specific examples thereof include ether solvents such as diethyl ether, tetrahydrofuran and tetrahydropyran; nitrogen-containing cyclic compound solvents such as pyridine and sulfur-containing cyclic compound solvents such as tetrahydrothiophene and the like Heterocyclic solvents such as: saturated aliphatic hydrocarbons such as butane, pentane, hexane and heptane; saturated alicyclic hydrocarbons such as cyclopentane and cyclohexane; aromatic hydrocarbons such as benzene and toluene; methylene chloride, chloroform, And halogenated hydrocarbons such as carbon chloride, trichloroethylene, perchlorethylene, 1,2-dichloroethane, chlorobenzene, bromobenzene, chlorotoluene and the like.
Of these, ether solvents such as tetrahydrofuran and diethyl ether and heterocyclic compound solvents are preferred.

  Preferable specific examples of the cation complex represented by the general formula (I) include (monochloro) di (bistrimethylsilylamide) scandium (tetrahydrofuran), (monochloro) di (bistrimethylsilylamide) yttrium (tetrahydrofuran), ( Monochloro) di (bistrimethylsilylamido) gadolinium (tetrahydrofuran).

The cation complex represented by the general formula (I) includes a halide of the Group 3 transition metal atom Ln of the periodic table and a metal salt of R ¹ and / or R ² in a solvent represented by the general formula Z. What is necessary is just to mix and react. At this time, this solvent coordinates to the periodic table group 3 transition metal atom Ln.
The solvent is not particularly limited as long as it is inert to the reaction and has solubility in the raw materials used for the reaction, and the same solvent molecules as those described above are preferably used.
Of these, ether solvents and heterocyclic compound solvents are more preferred, ether solvents are more preferred, and tetrahydrofuran is particularly preferred.

Although reaction conditions are not specifically limited, Reaction temperature is -78 degreeC-+200 degreeC normally, Preferably, it is -50 degreeC-+180 degreeC. The reaction time is usually 0.5 minutes to 48 hours, preferably 1 minute to 12 hours.
The reaction is preferably carried out in an inert gas atmosphere such as nitrogen.
From the reaction mixture, the solvent is removed, the resulting reaction product is dissolved in a nonpolar hydrocarbon solvent, and the insoluble matter is removed by filtration to precipitate crystals or remove the nonpolar hydrocarbon solvent. If necessary, purification by solvent washing or recrystallization is performed to obtain the target cation complex.

The structure of the obtained cation complex can be confirmed by ¹ H-NMR spectrum and X-ray structural analysis. In addition, elemental analysis, gas mass spectrometry, or the like may be used in combination.

The cation complex represented by the general formula (I) of the present invention is suitable as an olefin polymerization catalyst.
As the olefin, ethylene; α-olefin such as propylene, butene, pentene, hexene, octene; styrene, p-methylstyrene, m-methylstyrene, pt-butylstyrene, α-methylstyrene, chloromethylstyrene, p -Aromatic vinyl compounds such as t-butoxystyrene, dimethylaminomethylstyrene, dimethylaminoethylstyrene, vinyltoluene; butadiene, isoprene, 1,3-pentadiene, 2-ethyl-1,3-butadiene, 2,3-dimethyl Chain conjugated dienes such as butadiene, 2-methylpentadiene, 4-methylpentadiene, 2,4-hexadiene; cyclic monoolefins such as norbornene, vinylnorbornene, tetracyclododecene; cyclopentadiene, 1,3-cyclohexadiene, 1 , 3-shi And cyclic conjugated dienes such as clooctadiene; cyclic nonconjugated dienes such as dicyclopentadiene; and the like.

  Although the cation complex represented by the general formula (I) of the present invention can be used for homopolymerization or copolymerization of these olefins, it is preferably used for polymerization of conjugated dienes or ethylene, particularly preferably. Is used for homopolymerization of chain conjugated dienes and copolymerization of chain conjugated dienes.

A combination of a cation complex represented by the general formula (I) with an organoaluminum compound and / or an organoboron compound (hereinafter sometimes referred to as “olefin polymerization catalyst composition”) is also used as an olefin polymerization catalyst. Useful.
This catalyst composition for olefin polymerization is obtained by mixing a cation complex represented by the general formula (I) with an organoaluminum compound and / or an organoboron compound.
The mixing method is not particularly limited, and the components of the olefin polymerization catalyst composition may be mixed in a solid state or mixed in a solvent. The solvent is not particularly limited, but is preferably inert and industrially used. Specifically, such a solvent is preferably an aromatic hydrocarbon such as toluene, an aliphatic hydrocarbon solvent such as pentane, and a halogen solvent.
Although the temperature at the time of mixing is not specifically limited, Usually, it is -200 degreeC-+200 degreeC, Preferably it is -150 degreeC-+150 degreeC, More preferably, it is the range of -100 degreeC-+100 degreeC.
Also, the order of mixing is not particularly limited.

  Moreover, this olefin polymerization catalyst composition may be synthesized and used in situ by separately adding a cation complex and an organoaluminum compound and / or an organoboron compound to the polymerization system.

Examples of organoaluminum compounds include hydrocarbyl aluminum, hydrocarbyl aluminum halide, and organoaluminum oxy compounds.
Specific examples of hydrocarbyl aluminum include trimethylaluminum, triethylaluminum, triisoprenylaluminum and the like.
The amount of hydrocarbyl aluminum or hydrocarbyl aluminum halide is such that the molar ratio of group 3 transition metal atoms in the cation complex to aluminum atoms in the hydrocarbyl aluminum or hydrocarbyl aluminum halide is 1: 0.1 to 1: 100. Is preferable, the range of 1: 0.5 to 1:50 is more preferable, and the range of 1: 1 to 1:20 is still more preferable.

Specific examples of the organoaluminum oxy compound include methylaluminoxane, ethylaluminoxane, propylaluminoxane, butylaluminoxane, isobutylaluminoxane, methylethylaluminoxane, methylbutylaluminoxane, methylisobutylaluminoxane and the like. These may be modified.
The amount of the organoaluminum oxy compound is preferably in the range where the molar ratio of Group 3 transition metal atom in the cation complex to the aluminum atom in the organoaluminum oxy compound is 1: 0.1 to 1: 10,000. The range of 1: 0.5 to 1: 5,000 is more preferable, and the range of 1: 1 to 1: 2,000 is more preferable.

As the organic boron compound, a general formula BR ₃ (wherein R may be the same as or different from each other, may be a phenyl group or fluorine which may have a substituent such as fluorine, methyl group, trifluoromethyl group, etc.) Borane represented by: decaborane (B ₁₀ H ₁₄ ); onium borate such as phosphonium borate, ammonium borate, anilium borate, carbenium borate, ferrocenium borate; metal carborane anion salt; be able to.

Specific examples of borane include tris (pentafluorophenyl) borane and decaborane.
Specific examples of the phosphonium borate include tri (dimethylphenyl) phosphonium tetra (phenyl) borate.
Specific examples of the ammonium borate include trimethylammonium tetra (p-tolyl) borate and dicyclohexylammonium tetra (phenyl) borate.
Specific examples of anilium borate include N, N-dimethylanilinium tetrakis (pentafluorophenyl) borate and N, N-dimethylanilinium tetrakis (phenyl) borate.
Specific examples of carbenium borate include triphenylcarbenium tetrakis (pentafluorophenyl) borate.
Specific examples of ferrocenium borate include ferrocenium tetra (pentafluorophenyl) borate.
Specific examples of the metal carborane anion salt include tri (n-butyl) ammonium bis (undecahydride-7,8-dicarbaundecaborate) ironate (III).
The amount of the organoboron compound is preferably in the range where the molar ratio of Group 3 transition metal atom in the cation complex to boron atom in the organoboron compound is 1: 0.1 to 1: 10,000. : The range of 0.5-1: 5,000 is more preferable, and the range of 1: 1-1: 2,000 is still more preferable.

  In addition to the above, organoaluminum compounds and organoboron compounds include JP-A-1-501950, JP-A-1-502036, JP-A-3-179005, JP-A-3-179006, JP-A-3-17906. Examples disclosed in JP-A-3-207703, JP-A-3-207704, US Pat. No. 5,321,106 and the like can be mentioned.

When the olefin is polymerized using the olefin polymerization catalyst of the present invention, it may be carried out in a solvent or without a solvent. In particular, in the case of ethylene or the like which is a gas at room temperature, the polymerization can be performed in the gas phase.
The solvent is not particularly limited as long as it is inert to the reaction. Specific examples thereof include saturated aliphatic hydrocarbons such as butane, pentane, hexane and heptane; saturated alicyclic hydrocarbons such as cyclopentane and cyclohexane; aromatic hydrocarbons such as benzene and toluene; ethers such as tetrahydrofuran and dioxane. And halogenated hydrocarbons such as methylene chloride, chloroform, carbon tetrachloride, trichloroethylene, perchloroethylene, 1,2-dichloroethane, chlorobenzene, bromobenzene, chlorotoluene, and the like.
Among these, saturated alicyclic hydrocarbons and aromatic hydrocarbons are preferable, and heptane, cyclohexane and toluene are particularly preferable.

  When the polymerization is performed in a solvent, the monomer concentration is preferably 1 to 50% by weight, more preferably 2 to 45% by weight, and particularly preferably 5 to 40% by weight, based on the weight of the solution. If the monomer concentration is too low, the productivity may be poor, or the cis content may be reduced when polymerizing conjugated dienes.If it is too high, the solution viscosity after polymerization is too high, and the subsequent handling is difficult. It can be difficult.

  The amount of the olefin polymerization catalyst used in the present invention is usually in a range where the molar ratio of Group 3 transition metal atom to olefin monomer in the periodic table in the olefin polymerization catalyst is 1: 100 to 1: 2,000,000. And preferably in the range of 1: 200 to 1,000,000, more preferably 1: 500 to 1: 500,000. If the amount of the catalyst is too large, it is not economical, and if the catalyst needs to be removed, the operation becomes difficult. On the other hand, if the amount is too small, sufficient polymerization activity may not be obtained.

  The polymerization reaction temperature is not particularly limited and may be appropriately determined depending on the target olefin, the type of solvent used, and the like, but is usually −30 ° C. to + 200 ° C., preferably 0 ° C. to + 180 ° C.

The polymerization time is not particularly limited, and is usually about 0.5 minute to 48 hours, preferably about 1 minute to 5 hours.
After the polymerization reaction reaches a predetermined polymerization conversion rate, the polymerization is stopped by a conventional method, and then the produced polymer is separated from the polymerization reaction system and purified if necessary.

The molecular weight of the polymer obtained using the catalyst of the present invention is preferably a polymer having a weight average molecular weight measured by gel permeation chromatography (GPC) of 1,000 to 1,000,000. Yes, preferably 5,000 to 800,000, more preferably 10,000 to 650,000. If the weight average molecular weight is too small, the mechanical strength is insufficient and molding is difficult, and if it is too large, the melt viscosity is too high and molding is difficult.
Further, the cis-1,4-structure content of the diene polymer obtained using the catalyst of the present invention is usually 80 mol% or more, preferably 90 mol% or more, particularly preferably 95 mol%. That's it.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the scope of the present invention is not limited to these examples.
The identification of the cation complex and the evaluation of the characteristics of the polymer were performed by the following methods.
(Identification of cation complex)
^{By 1} H-NMR measurement (in heavy benzene solvent, room temperature) and X-ray crystal structure analysis.
[Weight average molecular weight (Mw) and number average molecular weight (Mn) of polymer]
It shows as a polystyrene conversion value by gel permeation chromatography (GPC) using chloroform as a solvent.

[Micro structure of polybutadiene]
Peaks obtained by ¹ H-NMR and ¹³ C-NMR { ¹ H-NMR: δ (ppm): 4.8-5.0 (= CH ₂ of 1,2-vinyl unit), δ (ppm): 5.2-5.8 (—CH═ of 1,4-unit and —CH═ of 1,2-vinyl unit); ¹³ C-NMR: δ (ppm): 27.4 (1,4-cis unit) ), Δ (ppm): 32.7 (1,4-trans unit), δ (ppm): 127.7-131.8 (1,4-unit) and δ (ppm): 113.8-114. 8 and δ (ppm): 143.3-144.7 (1,2-vinyl unit)}.
[Microstructure of polyisoprene]
Peaks {δ (ppm): 23.4 (1,4-cis units), δ (ppm): 18.6 (3,4-units) and δ (ppm) obtained by ¹³ C-NMR: 15. 9 (1,4-trans unit)}.

(Example 1)
Synthesis of [monochloro] scandium (III) di [bis (trimethylsilylamide)] tetrahydrofuran complex Under a nitrogen stream, 15.51 parts of potassium bistrimethylsilylamide and 6.55 parts of scandium (III) chloride were placed in a glass reactor. 177 parts of tetrahydrofuran were added. The resulting mixture was stirred at room temperature for 8 hours. After removing the solvent under reduced pressure, the resulting residue was extracted with hexane, and the supernatant was recrystallized in hexane to obtain 5.60 parts of the target cation complex (a1) crystals.
The ¹ H-NMR spectrum of (a1) was as follows.
d ppm: 0.38 (s, 36H), 1.17 (m, 4H), 4.00 (m, 4H).
The ¹ H-NMR spectrum of (a1) and the results of X-ray crystal structure analysis (ORTEP diagram) are shown in FIGS. 1 and 2, respectively. In FIG. 1, “Me” represents a methyl group, and “thf” represents tetrahydrofuran.
From the above, (a1) was identified as [monochloro] scandium (III) di [bis (trimethylsilylamide)] tetrahydrofuran complex (a1).

(Example 2)
(Polybutadiene polymerization)
Modified methylaluminoxane (trade name “MMAO-3A” manufactured by Tosoh Funchem Co., Ltd.) 1 dissolved in 0.12 part of (a1) obtained in Example 1 and 8.8 parts of toluene in a glass reactor substituted with nitrogen 1 A catalyst solution was prepared by mixing 5 parts.
Next, 5.4 parts of butadiene and 130 parts of toluene were charged into a pressure-resistant glass reactor equipped with a stirrer purged with nitrogen, and the above catalyst solution was added to initiate polymerization. After reacting at room temperature for 0.5 hours, the polymerization reaction solution is poured into a large amount of hydrochloric acid methanol to completely precipitate the polymer, washed by filtration, and dried under reduced pressure at 60 ° C. for 18 hours to obtain 2.5 parts of polybutadiene. Obtained.
The weight average molecular weight (Mw) of the obtained polybutadiene was 356,100, the number average molecular weight (Mn) was 44,600, and the microstructure of the polymer had a cis content of 85.4%.

(Example 3)
(Polybutadiene polymerization)
A polymerization reaction was carried out in the same manner as in Example 2 except that 10.8 parts of butadiene was used instead of 5.40 parts of butadiene to obtain 6.90 parts of a polymer. The weight average molecular weight (Mw) of the obtained polymer was 630,300, the number average molecular weight (Mn) was 125,400, and the microstructure of the polymer had a cis content of 91.3%.

Example 4
(Polybutadiene polymerization)
A polymerization reaction was carried out in the same manner as in Example 2 except that 0.23 part of triphenylcarbenium tetrakis (pentafluorophenyl) borate was used instead of 1.50 parts of modified methylaluminoxane to obtain 1.03 parts of polybutadiene. . The resulting polybutadiene had a weight average molecular weight (Mw) of 138,500, a number average molecular weight (Mn) of 52,900, and the polymer microstructure had a cis content of 95.2%.

(Example 5)
(Polymerization of isoprene)
A polymerization reaction was performed in the same manner as in Example 2 except that 6.80 parts of isoprene was used instead of 5.40 parts of butadiene, to obtain 6.32 parts of polyisoprene. The resulting polyisoprene had a weight average molecular weight (Mw) of 631,200, a number average molecular weight (Mn) of 301,600, and the polymer microstructure had a cis content of 92.1%.

(Example 5)
(Ethylene polymerization)
Instead of 5.4 parts of butadiene, a polymerization reaction was performed in the same manner as in Example 2 except that ethylene was supplied to the reactor at a pressure of 0.2 MPa to obtain 9.90 parts of polyethylene.

1 is a ¹ H-NMR spectrum of a cation complex (a1) obtained in Example 1. FIG. 4 is an X-ray crystal structure analysis diagram (hydrogen atom omitted) of the cation complex (a1) obtained in Example 1 [ORTEP (Oak Ridge Thermal Ellipsoid Plot) (Oak Ridge Ellipsoid Plot)]. 3 is a ¹³ C-NMR spectrum of the polybutadiene obtained in Example 3.

Claims (8)

A cation complex represented by the general formula (I).

[However, in general formula (I), Ln is a periodic table group 3 transition metal atom. X is a halogen atom. R ¹ and R ² are each a hydrogen atom, a halogen atom or a hydrocarbon group having 1 to 12 carbon atoms, and these hydrocarbon groups have at least one carbon atom as nitrogen, phosphorus, oxygen, sulfur or silicon. It may be replaced with an atom. Z is a solvent molecule. p represents an integer of 1 or 2. ]   An olefin polymerization catalyst comprising the cation complex according to claim 1.   The olefin polymerization catalyst according to claim 2, further comprising at least one of an organoaluminum compound and an organoboron compound.   The olefin polymerization catalyst according to claim 2 or 3, wherein the olefin is conjugated diene or ethylene.   An olefin polymerization method using the olefin polymerization catalyst according to claim 2.   The olefin polymerization method according to claim 5, wherein the olefin is conjugated diene or ethylene.   An olefin polymer obtained by the polymerization method according to claim 5.   The olefin polymer according to claim 7, which has a weight average molecular weight of 1,000 to 1,000,000 as measured by gel permeation chromatography (GPC).

Images