JP2741892B2 - Olefin polymerization catalyst and olefin polymerization method using the catalyst - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a catalyst for olefin polymerization and a method for polymerizing olefins using the catalyst. More specifically, the present invention has excellent polymerization activity and has a narrow molecular weight distribution and narrow composition distribution. The present invention also relates to a novel catalyst for olefin polymerization capable of obtaining an olefin (co) polymer having excellent stereoregularity, and a method for polymerizing olefins using this catalyst.

TECHNICAL BACKGROUND AND PROBLEMS OF THE INVENTION Conventionally, as a catalyst for producing an α-olefin polymer such as an ethylene polymer or an ethylene / α-olefin copolymer, a titanium-based catalyst comprising a titanium compound and organoaluminum or vanadium has been used. Vanadium-based catalysts comprising a compound and an organoaluminum compound are known.

In general, ethylene / α- obtained using a titanium-based catalyst
The olefin copolymer has a problem that the molecular weight distribution and the composition distribution are wide and the transparency, the surface non-adhesiveness, and the mechanical properties are poor. In addition, the ethylene-α-olefin copolymer obtained using a vanadium-based catalyst has a narrower molecular weight distribution and composition distribution than the ethylene-α-olefin copolymer obtained using a titanium-based catalyst, and has a higher transparency. Although the surface non-stickiness and the mechanical properties were considerably improved, the polymerization activity was low, and a decalcification operation was required. Therefore, there is a need for a catalyst system with improved performance.

On the other hand, as a new Ziegler type olefin polymerization catalyst, a method for producing an ethylene / α-olefin copolymer using a catalyst comprising a zirconium compound and an aluminoxane has been recently proposed.

For example, JP-A-58-19309 discloses that the following formula (cyclopentadienyl) ₂ MeRHal wherein R is cyclopentadienyl, C _{1 to} C ₆ alkyl or halogen, and Me is a transition metal And Hal is a halogen], and a transition metal-containing compound represented by the formula:
The following formula Al ₂ OR ₄ (AL (R) —O) _n [where R is methyl or ethyl, and n is 4 to 20]
Or a linear aluminoxane represented by the following formula: In the presence of a catalyst comprising a cyclic aluminoxane represented by the formula: wherein R and n are the same as defined above, one or more of ethylene and a C _{3 to} C ₁₂ α-olefin may be used. A method for producing an ethylene / α-olefin copolymer which is polymerized at a temperature of −50 ° C. to 200 ° C. is described. The publication teaches that to control the density of the resulting polyethylene, the polymerization of ethylene should be carried out in the presence of small amounts of up to 10% by weight of somewhat longer chain α-olefins or mixtures. I have.

JP-A-59-95292 discloses the following formula: [Where n is 2 to 40, R is C _{1 to} C ₆ ] and a linear aluminoxane represented by the following formula: [Wherein the definitions of n and R are the same as described above], the invention relating to a method for producing a cyclic aluminoxane represented by the formula: The publication discloses that, for example, when methylaluminoxane and a bis (cyclopentadienyl) compound of titanium or zirconium produced by the same production method are mixed and olefin is polymerized, 1 g of transition metal and It is stated that over 25 million g of polyethylene are obtained per hour.

JP-A-60-35005 discloses the following formula: Wherein R ¹ is C ₁ -C ₁₀ alkyl and R ⁰ is R ¹ or is bonded to and represents —O—. The aluminoxane compound represented by the formula A method is disclosed for producing a olefin polymerization catalyst by chlorinating the reaction product and treating it with a compound of Ti, V, Zr or Cr. And in the publication, it is described as being particularly suitable for the copolymerization of a mixture of the catalyst and α- olefin of ethylene and C ₃ -C _12.

JP-A-60-35006 discloses, as a catalyst system for producing a reactor blend polymer, mono-, di- or tri-cyclopentadienyl of two or more different transition metals or a derivative (a) thereof and alumino. Combinations with xane (b) are disclosed. In Example 1 of the publication, ethylene and propylene were polymerized using a catalyst composed of bis (pentamethylcyclopentadienyl) zirconium dimethyl and aluminoxane to obtain a number average molecular weight of 15,300,
It is disclosed that a polyethylene having a weight average molecular weight of 36,400 and a propylene component of 3.4% was obtained. Also,
In Example 2, ethylene and propylene were polymerized using a catalyst composed of bis (pentamethylcyclopentadienyl) zirconium dichloride, bis (methylcyclopentadienyl) zirconium dichloride, and aluminoxane. Average molecular weight 2,200, weight average molecular weight 1
A number-average molecular weight of 2,000, a weight-average molecular weight of 8,300 and 7.1 moles consisting of a toluene-soluble portion containing propylene components of 1,900 and 30 mol% and a toluene-insoluble portion containing 3,000, number-average molecular weights 7,400 and 4.8 mol% of propylene components. % Of a propylene component and a blend of polyethylene and an ethylene-propylene copolymer. Similarly, in Example 3, the molecular weight distribution (w / n) was 4.
A blend of LLDPE and an ethylene-propylene copolymer comprising 57 and a soluble portion of 20.6 mol% of the propylene component and a molecular weight distribution of 3.04 and an insoluble portion of 2.9 mol% of the propylene component is described.

JP-A-60-35007 discloses ethylene alone or a mixture of ethylene and an α-olefin having 3 or more carbon atoms with a metallocene and a compound represented by the following formula: [Where R is an alkyl group having 1 to 5 carbon atoms, and n is an integer of 1 to about 20], or the following formula R (R-Al-O) _n AlR ₂ [ Here, R is an alkyl group having 1 to 5 carbon atoms, and the definition of n is the same as described above.] And a linear aluminoxane represented by the following formula: I have. According to the publication, the polymer thus obtained has a weight average molecular weight of about 500 to about 1.4 million and a molecular weight distribution of 1.5 to 4.0.

The JP 60-35008 discloses, by using a catalyst system comprising at least two metallocenes and aluminoxane, and α- olefin polyethylene or ethylene and C ₃ -C ₁₀ having a width broader molecular weight distribution Is described as being produced. The publication describes that the copolymer has a molecular weight distribution (w / n) of 2 to 50.

JP-A-60-260602 and JP-A-60-130604 disclose a method of polymerizing an olefin using a catalyst formed from a mixed organoaluminum compound comprising a transition metal compound, an aluminoxane and an organoaluminum compound. And that the addition of an organoaluminum compound improves the polymerization activity per unit transition metal.

Further, JP-A-62-36390 teaches that an aluminoxane can be obtained by reacting an organoaluminum compound with an iron compound containing water of crystallization. The gazette teaches that aluminoxane can be obtained by reacting an organoaluminum compound with a compound containing water of crystallization selected from the group consisting of a magnesium compound, a nickel compound and a lanthanide compound. Kaisho
JP-A-63-56507 and JP-A-63-56508 use a high-speed, high-breaking-force induction impeller or ultrasonic waves.
It is taught that aluminoxane can be obtained by directly reacting water and an organoaluminum compound in an inert hydrocarbon solvent.

When an aluminoxane compound is used as one component of the catalyst in producing the α-olefin (co) polymer in this way, the α-olefin (co) polymer having excellent polymerization activity and a narrow molecular weight distribution and composition distribution can be obtained. Can be manufactured.

However, there is a strong demand for an aluminoxane-based organoaluminum compound which has a more excellent polymerization activity for α-olefins and can obtain an olefin (co) polymer having a narrow molecular weight distribution and composition distribution. ing.

The aluminoxane compounds that have been used for conventionally known olefin polymerization have all been recovered in a state of being soluble in benzene or toluene, and their molecular weights have been measured by dissolving in benzene and using a freezing point depression method. . The structure of the aluminoxane has also been determined by dissolving it in benzene and measuring the freezing point.

The present inventors have conducted further intensive studies in view of the above points, and found that an organic aluminum oxy compound which was insoluble or hardly soluble in benzene and toluene, which had never been known before, has an excellent catalytic activity for olefin polymerization. To complete the present invention.

Object of the Invention The present invention is intended to solve the problems associated with the prior art as described above, has excellent catalytic activity, has a narrow molecular weight distribution and composition distribution, and has excellent stereoregularity. An object of the present invention is to provide an olefin polymerization catalyst capable of obtaining an olefin polymer and a method for polymerizing an olefin using the catalyst.

SUMMARY OF THE INVENTION The olefin polymerization catalyst according to the present invention comprises: [A] an Al component soluble in benzene at 60 ° C.
Less than 10%, An organoaluminum oxy compound having an alkyloxyaluminum unit represented by the formula: [B] two ligands having a cyclopentadienyl skeleton, and two of the ligands having a cyclopentadienyl skeleton are lower A transition metal compound containing a transition metal selected from the group consisting of titanium, zirconium and hafnium bonded through an alkylene group, and [C] a formula R ⁶ _n AlX _3-n (where R ⁶ is carbon And X is a halogen group, and n is 1 to 3).

Further, the olefin polymerization method according to the present invention is characterized in that an α-olefin is polymerized or copolymerized using the olefin polymerization catalyst as described above.

The olefin polymerization catalyst according to the present invention comprises: [A] an organoaluminum oxy compound insoluble or hardly soluble in benzene, and [B] at least two ligands having a cyclopentadienyl skeleton; A transition metal compound in which a ligand having a cyclopentadienyl skeleton is bonded via a lower alkylene group;
Since it is formed from an organoaluminum compound, it is possible to obtain an olefin polymer having excellent polymerization activity for olefin polymerization, narrow molecular weight distribution and composition distribution, and excellent in stereoregularity.

DETAILED DESCRIPTION OF THE INVENTION Hereinafter, the olefin polymerization catalyst according to the present invention and the olefin polymerization method using the olefin polymerization catalyst will be specifically described.

In the present invention, the term "polymerization" is sometimes used to mean not only homopolymerization but also copolymerization, and the term "polymer" means not only homopolymer but also copolymer. May be used.

The olefin polymerization catalyst according to the present invention comprises [A] a benzene-insoluble organoaluminum oxy compound and [B] a ligand having a cyclopentadienyl skeleton at least two.
And a ligand having at least two cyclopentadienyl skeletons, the transition metal compound being bound via a lower alkylene group, and [C] an organoaluminum compound.

[A] Benzene-insoluble organoaluminum oxy compound [A] The benzene-insoluble organoaluminum oxy compound used in the present invention is Al
The component is 10% or less, preferably 5% or less, particularly preferably 2% or less in terms of Al atom, and is insoluble or hardly soluble in benzene.

The solubility of such an organoaluminum oxy compound in benzene is determined by suspending the organoaluminum oxy compound corresponding to 100 milligram atoms of Al in 100 ml of benzene, mixing at 60 ° C. with stirring for 6 hours, and applying a jacket. Using a G-5 glass filter, filtration was carried out while heating at 60 ° C., and the solid part separated on the filter was washed four times with 50 ml of benzene at 60 ° C., and then the total amount of Al atoms present in the total filtrate was measured. It is determined by measuring the abundance (x mmol) (x%).

When the [A] benzene-insoluble organoaluminum oxy compound as described above is analyzed by infrared spectroscopy (IR), the absorbance (D ₁₂₂₀ ) around ₁₂₂₀ cm ⁻¹ and the 1260 c
The ratio to the absorbance (D ₁₂₆₀ ) around m ^-1 (D ₁₂₆₀ /
D ₁₂₂₀ ) is 0.09 or less, preferably 0.08 or less, and particularly preferably 0.04 to 0.07.

In the present specification, infrared spectroscopy of an organoaluminum oxy compound is performed as follows.

First, in a nitrogen box, the organoaluminum oxy compound and nujol are ground in an agate mortar to form a paste.

Next, the paste-like sample is sandwiched between KBr plates, and an IR spectrum is measured by IR-810 manufactured by JASCO Corporation under a nitrogen atmosphere.

Of the organoaluminum oxy compound used in the present invention
FIG. 1 shows the IR spectrum.

From the IR spectrum thus obtained, D ₁₂₆₀ / D
_The value of D ₁₂₆₀ / D ₁₂₂₀ is obtained as follows.

(B) 1280 cm ^-1 bear maximum point in the vicinity of and around 1240 cm ^-1, which is the baseline L _1.

(B) the transmittance (T%) at the absorption minimum point near 1260 cm _-1 ,
A vertical line with wavenumber axis (horizontal axis) from the minimum point, reads the transmittance of intersection of the perpendicular line and the baseline _{L 1 (T 0%),} 1260cm -1 vicinity of absorbance (D ₁₂₆₀ = log T _O / T).

(C) Similarly bear maximum point in the vicinity of 1280 cm ^-1 and near 1180 cm ^-1, which is the baseline L _2.

(D) Transmittance at the minimum absorption point near 1220 cm ^-1 (T '%)
From this minimum point, a perpendicular is drawn to the wave number axis (horizontal axis), and the transmittance (T ′) at the intersection of this perpendicular and the baseline L ₂ is drawn.
₀ %) and read the absorbance around ₁₂₂₀ cm ^-1 (D ₁₂₂₀ = log
T ′ ₀ / T ′) is calculated.

(E) These values calculate D ₁₂₆₀ / D ₁₂₂₀ .

FIG. 2 shows the IR spectrum of a conventionally known benzene-soluble organoaluminum oxy compound. As can be seen from FIG. 2, the benzene-soluble organoaluminum oxy compound has a D ₁₂₆₀ / D ₁₂₂₀ value of about 0.10 to 0.13.
The benzene-insoluble organoaluminum oxy compound used in the present invention is clearly different from the conventionally known benzene-soluble organoaluminum oxy compound in the value of D ₁₂₆₀ / D ₁₂₂₀ .

[A] The benzene-insoluble organoaluminum oxy compound as described above is [Wherein, R ¹ is a hydrocarbon group having 1 to 12 carbon atoms].

In the above alkyloxyaluminum unit, R ¹
Is specifically exemplified by methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, pentyl, hexyl, octyl, decyl, cyclohexyl, cyclooctyl, etc. it can. Of these, a methyl group and an ethyl group are preferable, and a methyl group is particularly preferable.

The above [A] benzene-insoluble organoaluminum oxy compound is represented by the formula In addition to the alkyloxyaluminum unit represented by Wherein R ¹ is the same as above, and R ² is a hydrocarbon group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, and an aryloxy group having 6 to 20 carbon atoms. , Hydroxyl, halogen or hydrogen, R ¹ and R ²
Represents different groups from each other]. In that case, the alkyloxyaluminum unit Is preferably an organoaluminum oxy compound having an alkyloxyaluminum unit containing at least 30 mol%, preferably at least 50 mol%, particularly preferably at least 70 mol%.

Next, the method for producing the above-mentioned [A] benzene-insoluble organic aluminum oxy compound will be specifically described.

[A] The benzene-insoluble organoaluminum oxy compound [A] is obtained by contacting a solution of aluminoxane with water or an active hydrogen-containing compound.

The aluminoxane solution used here can be produced, for example, by the following method.

(1) Compounds containing water of adsorption or salts containing water of crystallization, such as hydrated magnesium chloride, hydrated copper sulfate, hydrated aluminum sulfate, hydrated nickel sulfate, hydrated cerous chloride A method of adding an organoaluminum compound such as a trialkylaluminum to a suspension of a hydrocarbon medium of Example 1 and reacting the suspension to recover a hydrocarbon solution.

(2) A method in which an organic aluminum compound such as trialkylaluminum is directly allowed to act on water, ice or steam in a medium such as benzene, toluene, ethyl ether, or tetrahydrofuran to recover as a hydrocarbon solution.

The aluminoxane may contain a small amount of an organic metal component. Alternatively, the solvent or unreacted organoaluminum compound may be removed from the recovered solution of aluminoxane by distillation, and then redissolved in the solvent.

Specific examples of the organoaluminum compound used when producing the solution of aluminoxane include trimethylaluminum, triethylaluminum, tripropylaluminum, triisopropylaluminum, trin-butylaluminum, triisobutylaluminum, and trisec-. Trialkyl aluminum such as butyl aluminum, tri-tert-butyl aluminum, tripentyl aluminum, trihexyl aluminum, trioctyl aluminum, tridecyl aluminum, tricyclohexyl aluminum, tricyclooctyl aluminum, dimethyl aluminum chloride, diethyl aluminum chloride, diethyl aluminum bromide ,
Dialkyl aluminum halides such as diisobutyl aluminum chloride, diethyl aluminum hydride, dialkyl aluminum hydrides such as diisobutyl aluminum hydride, dimethyl aluminum methoxide, dialkyl aluminum alkoxides such as diethyl aluminum ethoxide, and dialkyl aluminum aryloxides such as diethyl aluminum phenoxide. Can be

Of these, trialkyl aluminum is particularly preferred.

Further, as the organoaluminum compound, isoprenyl aluminum represented by the general formula (iC ₄ H ₉ ) _x Al _y (C ₅ H ₁₀ ) _z (x, y, and z are positive numbers and z ≧ 2x) Can also be used.

The above-mentioned organoaluminum compounds are used alone or in combination.

Solvents used in the solution of aluminoxane include:
Aromatic hydrocarbons such as benzene, toluene, xylene, cumene, cymene, aliphatic hydrocarbons such as pentane, hexane, heptane, octane, decane, dodecane, hexadecane, octadecane, cyclopentane, cyclohexane, cyclooctane, methylcyclopentane, etc. Petroleum fractions such as alicyclic hydrocarbons, gasoline, kerosene and light oil, or hydrocarbon solvents such as the above aromatic hydrocarbons, aliphatic hydrocarbons and halides of alicyclic hydrocarbons, especially chlorinated compounds and brominated compounds. No. In addition, ethers such as ethyl ether and tetrahydrofuran can also be used. Among these solvents, aromatic hydrocarbons are particularly preferred.

In the present invention, as described above, by contacting the above aluminoxane solution with water or an active hydrogen-containing compound, [A] a benzene-insoluble organic aluminum oxy compound can be obtained.

Examples of the active hydrogen-containing compound used in the present invention include alcohols such as methanol, ethanol, n-propanol and isopropal, diols such as ethylene glycol and hydroquinone, and organic acids such as acetic acid and propionic acid. Of these, alcohols and diols are preferred, and alcohols are particularly preferred.

The water or active hydrogen-containing compound to be brought into contact with the solution of aluminoxane is dissolved or dispersed in a hydrocarbon solvent such as benzene, toluene, or hexane, an ether solvent such as tetrahydrofuran, an amine solvent such as triethylamine, or steam or It can be used in a solid state. Also, as water, magnesium chloride,
Water of crystallization of salts such as magnesium sulfate, aluminum sulfate, copper sulfate, nickel sulfate, iron sulfate and cerous chloride, or water adsorbed on inorganic compounds or polymers such as silica, alumina and aluminum hydroxide may be used. it can.

The contact reaction between the solution of aluminoxane and water or an active hydrogen-containing compound is usually carried out in a solvent such as a hydrocarbon solvent. Examples of the solvent used in this case include aromatic hydrocarbons such as benzene, toluene, xylene, cumene and cymene, aliphatic hydrocarbons such as pentane, hexane, heptane, octane, decane, dodecane, hexadecane and octadecane, cyclopentane and cyclohexane. , Cyclooctane, alicyclic hydrocarbons such as methylcyclohexane, hydrocarbon solvents such as gasoline, kerosene, petroleum fractions such as light oil, and the above-mentioned aromatic hydrocarbons, aliphatic hydrocarbons, halides of alicyclic hydrocarbons And halogenated hydrocarbons such as chlorinated products and brominated products, and ethers such as ethyl ether and tetrahydrofuran. Among these media, aromatic hydrocarbons are particularly preferred.

Water or an active hydrogen-containing compound used in the catalytic reaction is 0.1 to 0.1% of Al atoms in the solution of aluminoxane.
It is used in an amount of 5 mol, preferably 0.2 to 3 mol. The concentration in the reaction system is usually 1 ×
The concentration is preferably in the range of 10 ^{−3 to} 5 g atom / l, preferably 1 × 10 ^{−2 to} 3 g atom / l, and the concentration of water in the reaction system is usually 2 × 10 ^{−4 to} 5 mol / l. l preferably 2 × 10 ^-3
Preferably, the concentration is 3 mol / l.

The contact of the aluminoxane solution with water or an active hydrogen-containing compound may be carried out specifically as follows.

(1) A method in which a solution of aluminoxane is brought into contact with water or a hydrocarbon solvent containing an active hydrogen-containing compound.

(2) A method in which water or an active hydrogen-containing compound vapor is blown into a solution of aluminoxane to bring the aluminoxane into contact with the vapor.

(3) A method in which a solution of aluminoxane is brought into direct contact with water, ice or an active hydrogen-containing compound.

(4) Aluminoxane solution is mixed with a hydrocarbon suspension of a compound containing adsorbed water or a water of crystallization or a hydrocarbon suspension of a compound to which an active hydrogen-containing compound is adsorbed. And contacting the water with the adsorbed water or water of crystallization.

The aluminoxane solution as described above may contain other components as long as the reaction between the aluminoxane and water or the active hydrogen-containing compound is not adversely affected.

The contact reaction between the solution of aluminoxane and water or an active hydrogen-containing compound is usually carried out at -50 to 150 ° C, preferably at 0 to 1 ° C.
The reaction is carried out at a temperature of 20 ° C, more preferably 20 to 100 ° C.
The reaction time varies greatly depending on the reaction temperature,
Usually, it is about 0.5 to 300 hours, preferably about 1 to 150 hours.

The benzene-insoluble organoaluminum oxy compound [A] used in the present invention can also be directly obtained by contacting the above-mentioned organoaluminum with water. In this case, water is used in such an amount that the amount of the organic aluminum atoms dissolved in the reaction system is 20% or less based on all the organic aluminum atoms.

Water to be brought into contact with the organoaluminum compound can be used by dissolving or dispersing it in a hydrocarbon solvent such as benzene, toluene, and hexane, an ether solvent such as tetrahydrofuran, an amine solvent such as triethylamine, or in the form of steam or ice. . As water, it was adsorbed on water of crystallization of salts such as magnesium chloride, magnesium sulfate, aluminum sulfate, copper sulfate, nickel sulfate, iron sulfate, and cerous chloride, or on inorganic compounds or polymers such as silica, alumina and aluminum hydroxide. Adsorbed water or the like can also be used.

The contact reaction between the organoaluminum compound and water is usually
Performed in a hydrocarbon solvent. Examples of the hydrocarbon solvent used in this case include aromatic hydrocarbons such as benzene, toluene, xylene, cumene and cymene; aliphatic hydrocarbons such as pentane, hexane, heptane, octane, decane, dodecane, hexadecane and octadecane; and cyclopentane. , Cyclohexane, cyclooctane, alicyclic hydrocarbons such as methylcyclohexane, petroleum fractions such as gasoline, kerosene, and gas oil, or halides of the above aromatic hydrocarbons, aliphatic hydrocarbons, and alicyclic hydrocarbons, especially chlorinated products And hydrocarbon solvents such as bromides. In addition, ethers such as ethyl ether tetrahydrofuran can be used. Of these media, aromatic hydrocarbons are particularly preferred.

The concentration of the organoaluminum compound in the reaction system is usually in the range of 1 × 10 ^{−3 to} 5 g atoms / l, preferably 1 × 10 ^{−2 to} 3 g atoms / l in terms of aluminum atoms, The concentration of water in the reaction system is usually 1 × 10 ⁻³ to
The concentration is preferably 5 mol / l, preferably 1 × 10 ^{-2 to} 3 mol / l. At this time, the organic aluminum atoms dissolved in the reaction system are 20% of the total organic aluminum atoms.
% Or less, preferably 10% or less, more preferably 0 to 5%
It is desirable that

The contact between the organoaluminum compound and water may be specifically performed as follows.

(1) A method of contacting a hydrocarbon solution of organoaluminum with a hydrocarbon solvent containing water (2) A method of contacting organoaluminum with steam by blowing steam into the hydrocarbon solution of organoaluminum .

(3) A method in which a hydrocarbon solution of an organic aluminum is mixed with a hydrocarbon suspension of a compound containing adsorbed water or a compound containing water of crystallization, and the organic aluminum is brought into contact with the adsorbed water or the water of crystallization.

(4) A method in which ice is brought into contact with a hydrocarbon solution of an organic aluminum.

The organic aluminum hydrocarbon solution as described above may contain other components as long as the reaction between the organic aluminum and water is not adversely affected.

The contact reaction between the organoaluminum compound and water is usually
100-150 ° C, preferably -70-100 ° C, more preferably -5
It is performed at a temperature of 0 to 80 ° C. The reaction time varies greatly depending on the reaction temperature, but is usually about 1 to 200 hours, preferably about 2 to 100 hours.

The above-mentioned [A] organic aluminum oxy compound may be used by being supported on a solid inorganic compound such as silica, alumina, magnesium oxide, and magnesium chloride, or a solid organic compound such as polyethylene, polypropylene, and polystyrene. it can.

[B] Transition metal compound The olefin polymerization catalyst according to the present invention comprises the above-mentioned [A] benzene-insoluble organoaluminum oxy compound and the following [B] ligand having a cyclopentadienyl skeleton. A transition metal compound containing at least two or more ligands having at least two cyclopentadienyl skeletons bonded via a lower alkylene group, and [C] an organoaluminum compound to be described later. ing.

The [B] transition metal compound used in the present invention has the formula ML
_{In the} formula _X , M is a transition metal, L is a ligand coordinated to the transition metal, at least two Ls are ligands having a cyclopentadienyl skeleton, and at least two Ls are L other than a ligand having a cyclopentadienyl skeleton bonded through a lower alkylene group has 1 to 12 carbon atoms.
Is a hydrocarbon group, alkoxy group, aryloxy group, halogen or hydrogen, and x is the valence of the transition metal. )
Indicated by

In the above formula, M is a transition metal, and specifically, is preferably zirconium, titanium or hafnium, or chromium or vanadium, and among them, zirconium and hafnium are particularly preferable.

As the ligand having a cyclopentadienyl skeleton,
For example, alkyl-substituted cyclopentadienyl groups such as cyclopentadienyl group, methylcyclopentadienyl group, ethylcyclopentadienyl group, t-butylcyclopentadienyl group, dimethylcyclopentadienyl group and pentamethylcyclopentadienyl group Enyl, indenyl, 4,5,
A 6,7-tetrahydroindenyl group and the like can be exemplified.

The ligand other than the ligand having a cyclopentadienyl skeleton is a hydrocarbon group having 1 to 12 carbon atoms, an alkoxy group, an aryloxy group, a halogen or hydrogen.

Examples of the hydrocarbon group having 1 to 12 carbon atoms include an alkyl group, a cycloalkyl group, an aryl group, and an aralkyl group. Specifically, examples of the alkyl group include a methyl group, an ethyl group, and a propyl group. , An isopropyl group, a butyl group, and the like.Examples of the cycloalkyl group include a cyclopentyl group and a cyclohexyl group.Examples of the aryl group include a phenyl group and a tolyl group.Examples of the aralkyl group include a benzyl group, A neofil group is exemplified.

Examples of the alkoxy group include a methoxy group, an ethoxy group, and a butoxy group. Examples of the aryloxy group include a phenoxy group.

Examples of the halogen include fluorine, chlorine, bromine, and iodine.

The [B] ligand having at least two cyclopentadienyl skeletons used in the present invention is used, and the ligand having at least two cyclopentadienyl skeletons is linked via a lower alkylene group. The bound transition metal compound, for example, when the valence of the transition metal is 4, is more specifically represented by the formula R ² R ³ R ⁴ R ⁵ M (where M is zirconium, titanium, Hafnium or vanadium, and at least two of R ² , R ³ , R ⁴ and R ⁵ , that is, R ² and R ³ are groups having a cyclopentadienyl skeleton, and these two cyclopentadienyl skeletons are group is a lower alkylene such as ethylene with, is coupled via a propylene, R ⁴ and R ⁵ are each a group having a cyclopentadienyl skeleton, alkyl group, cycloalkyl group, Ali , An aralkyl group, an alkoxy group, an aryloxy group, a halogen atom or hydrogen.) Hereafter, at least two ligands having a [B] cyclopentadienyl skeleton where M is zirconium, Specific examples of the transition metal compound in which a ligand having two cyclopentadienyl skeletons are bonded via a lower alkylene group will be described.

Ethylene bis (indenyl) diethyl zirconium, ethylene bis (indenyl) diphenyl zirconium, ethylene bis (indenyl) methyl zirconium, ethylene bis (indenyl) methyl zirconium monochloride, ethylene bis (indenyl) methyl zirconium monobromide, ethylene bis (indenyl) zirconium Dichloride, ethylenebis (indenyl) zirconium dibromide, ethylenebis (indenyl) zirconium methoxymonochloride, ethylenebis (indenyl) zirconium ethoxymonochloride, ethylenebis (indenyl) zirconium phenoxymonochloride, ethylenebis (cyclopentadienyl) zirconium Dichloride, propylene bis (cyclopentadienyl) zirconium dichloride , Ethylenebis (t-butylcyclopentadienyl) zirconium dichloride, ethylenebis (4,5,6,7-tetrahydro-1-indenyl) dimethylzirconium, ethylenebis (4,5,6,7-tetrahydro-1) -Indenyl) methyl zirconium monochloride, ethylenebis (4,5,6,7-tetrahydro-1-indenyl) zirconium dichloride, ethylenebis (4,5,6,7-tetrahydro-1-indenyl) zirconium dibromide, ethylene Bis (4-methyl-1-indenyl) zirconium dichloride, ethylenebis (5-methyl-1-indenyl) zirconium dichloride, ethylenebis (6-methyl-1-indenyl) zirconium dichloride, ethylenebis (7-methyl-1- Indenyl) zirconium dichloride, ethylenebis (5 Methoxy-1-indenyl) zirconium dichloride, ethylenebis (2,3-dimethyl-1-indenyl) zirconium dichloride, ethylenebis (4,7-dimethyl-1-indenyl) zirconium dichloride, ethylenebis (4,7-dimethoxy- 1-indenyl)
Zirconium dichloride.

In the above zirconium compound, a transition metal compound in which zirconium metal is replaced with titanium metal, hafnium metal, chromium metal, vanadium metal, or the like can also be used.

Such [B] transition metal compounds may be used in combination of two or more.

In the present invention, at least two ligands having the [B] cyclopentadienyl skeleton are contained, and
When a ligand having two cyclopentadienyl skeletons is bonded via a lower alkylene group as a transition metal compound, using ethylenebisindenyl-based zirconium or hafnium as described above, particularly stereoregularity A high polymer is obtained.

[C] Organoaluminum Compound The [C] organoaluminum compound used in the present invention has the formula R _n ⁶ AlX _3-n (wherein R ⁶ is a hydrocarbon group having 1 to 12 carbon atoms, and X is halogen. And n is 1 to 3).

In the above formula, R ⁶ is a hydrocarbon group having 1 to 12 carbon atoms such as an alkyl group, a cycloalkyl group or an aryl group, and specifically, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an isobutyl group. Group, pentyl group, hexyl group, octyl group, decyl group, cyclopentyl group,
Cyclohexyl, phenyl, tolyl and the like.

Specific examples of such an organoaluminum compound include the following compounds.

Trimethyl aluminum, triethyl aluminum,
Trialkyl aluminums such as triisopropyl aluminum, triisobutyl aluminum, trioctyl aluminum and tri 2-ethylhexyl aluminum.

Alkenyl aluminum such as isoprenyl aluminum.

Dialkylaluminum halides such as dimethylaluminum chloride, diethylaluminum chloride, diisopropylaluminum chloride, diisobutylaluminum chloride and dimethylaluminum bromide.

Alkylaluminum sesquichlorides such as methylaluminum sesquichloride, ethylaluminum sesquichloride, isopropylaluminum sesquichloride, isobutylaluminum sesquichloride, and ethylaluminum sesquibromide.

Alkyl aluminum dihalides such as methyl aluminum dichloride, ethyl aluminum dichloride, isopropyl aluminum dichloride, isobutyl aluminum dichloride, ethyl aluminum dibromide.

As the organoaluminum compound, trialkylaluminum is preferable, trialkylaluminum containing a branched alkyl group is more preferable, and triisoalkylaluminum such as triisobutylaluminum and tri-2-ethylhexylaluminum is particularly preferable.
Two or more of these organoaluminum compounds can be used.

Olefin Polymerization Method FIG. 3 is a flowchart illustrating the olefin polymerization method according to the present invention.

In the present invention, [A] a benzene-insoluble organoaluminum oxy compound as described above, and [B] at least two ligands having a cyclopentadienyl skeleton, and at least two cyclopentadienyl skeletons An olefin polymer is produced by polymerizing an olefin using an olefin polymerization catalyst comprising a transition metal compound in which a ligand having the following formula: is bonded via a lower alkylene group, and an organic aluminum compound [C]. .

Examples of the olefin that can be polymerized by the olefin polymerization catalyst according to the present invention include ethylene and α-olefins having 3 to 20 carbon atoms, such as propylene,
-Butene, 1-hexene, 4-methyl-1-pentene,
1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene, cyclopentene, cycloheptene, norbornene, 5-methyl-2-norbornene, tetracyclododecene, 2-methyl -1,4,5,8-Dimethano-1,2,3,4,4a,
5,8,8a-octahydronaphthalene and the like can be mentioned.

Further, in the present invention, styrene, vinylcyclohexane, diene and the like can be used.

In the present invention, the polymerization can be carried out by either a liquid phase polymerization method such as solution polymerization or suspension polymerization or a gas phase polymerization method.

The polymerization temperature of the olefin using such an olefin polymerization catalyst is usually -50 to 200 ° C, preferably 0 to 150 ° C.
It is in the range of ° C. The polymerization pressure is usually from normal pressure to 100 kg / c.
m ² , preferably normal pressure to 50 kg / cm ² , and the polymerization reaction can be carried out by any of a batch system, a semi-continuous system, and a continuous system. Further, the polymerization can be performed in two or more stages under different reaction conditions. The molecular weight of the resulting olefin polymer can be adjusted by the presence of hydrogen in the polymerization system or by changing the polymerization temperature.

When olefin polymerization is carried out using the olefin polymerization catalyst as described above, [A] the benzene-insoluble organoaluminum oxy compound is usually 10 ^{-6 to} 0.1 g atom-Al / l, preferably 10 ^-5 to 10 ^-2 g atom-Al / l
And [B] at least two ligands having a cyclopentadienyl skeleton, and the ligands having at least two cyclopentadienyl skeletons are bonded via a lower alkylene group. The transition metal compound is usually in an amount of 10 ^-8 to 10 ^-3 mol / l, preferably 10 ^-7 to 10 ^-4 mol / l, and the [C] organoaluminum compound is usually 10 ^-5 mol / l.
To 0.1 mol / l, preferably 10 ^-4 to 10 ^-2 mol / l. The ratio of the benzene-insoluble organoaluminum oxy compound (in terms of Al atom) to the organoaluminum compound is preferably in the range of 0.01 to 5, preferably 0.02 to 2.

[A] a benzene-insoluble organoaluminum oxy compound as described above, and [B] a coordination comprising at least two ligands having a cyclopentadienyl skeleton and having at least two cyclopentadienyl skeletons The catalyst for olefin polymerization according to the present invention, which is formed from a transition metal compound in which a ligand is bonded via a lower alkylene group and [C] an organoaluminum compound, has excellent polymerization activity. That is, the olefin polymerization catalyst according to the present invention is compared with a conventionally known olefin polymerization catalyst formed from a benzene-soluble aluminoxane and a metallocene-based compound, and has a weight of about 1.2 to 20 per unit organic aluminum oxy compound. An olefin polymer can be obtained twice as much, and a polymer having a higher molecular weight can be obtained.

When the olefin is copolymerized using the olefin polymerization catalyst according to the present invention, the olefin (co) having a narrow molecular weight distribution, a narrow composition distribution, and excellent stereoregularity is obtained.
A polymer can be obtained.

In the present invention, the catalyst for olefin polymerization may contain other components useful for olefin polymerization, in addition to the above components.

Effect of the Invention The olefin polymerization catalyst according to the present invention comprises [A] an organic aluminum oxy compound insoluble or hardly soluble in benzene, and [B] at least two ligands having a cyclopentadienyl skeleton. A transition metal compound in which at least two ligands having a cyclopentadienyl skeleton are bonded via a lower alkylene group, [C]
Since it is composed of an organoaluminum compound, it has excellent polymerization activity for olefin polymerization, and when this catalyst is used to polymerize olefins, olefin copolymers with narrow molecular weight distribution and composition distribution, and high stereoregularity Can be obtained.

Hereinafter, the present invention will be described with reference to examples, but the present invention is not limited to these examples.

Example 1 [Preparation of aluminoxane] Al ₂ (SO ₄ ) _3.
After charging 37 g of 14H ₂ O and 125 ml of toluene and cooling to 0 ° C., trimethylaluminum 5 diluted with 125 ml of toluene was added.
00 mmol was added dropwise. Next, the temperature was raised to 40 ° C., and the reaction was continued at that temperature for 10 hours. After completion of the reaction, solid-liquid separation was performed by filtration, and further toluene was removed from the filtrate.
12 g of aluminoxane as a white solid was obtained.

[Preparation of benzene-insoluble organoaluminum oxy compound] In a 400 ml glass flask sufficiently purged with nitrogen, 59.7 ml of toluene and a toluene solution of aluminoxane (Al2.
(48 mol-Al / l) 40.3 ml and 25 g of a Teflon cylinder (φ2 mm × 1.2 mm) as a dispersant were charged. Then-
After cooling to 5 ° C., 0.72 ml of water was slowly added with a pipette.
Subsequently, the reaction was carried out at -5 ° C for 40 minutes, and then 80 hours over 1 hour.
C., and the reaction was continued at that temperature for another 3 hours.
After the reaction for 3 hours, the Teflon cylinder was removed with a sieve, and solid-liquid separation was further performed by filtration to obtain a benzene-insoluble organic aluminum oxy compound. When the concentration of aluminum dissolved in the filtrate was measured, the detection limit was 5 mg.
−Al / l or less.

The benzene-insoluble organoaluminum oxy compound obtained as described above was added to a 200-ml reactor equipped with a stirrer in an amount of 100 milligrams in terms of Al atom, and 100 ml of benzene was added, followed by stirring and mixing at 60 ° C. for 6 hours. This suspension was filtered using a jacketed G5 glass filter while hot while keeping the silicone oil poured into the jacket at 60 ° C, and washed four times with 50 ml of benzene at 60 ° C. The filtrate was collected, and the amount of Al in the filtrate was measured.
7 mmol of Al was detected. That is, the organic aluminum oxy compound is dissolved in benzene at 60 ° C.
The amount of the Al component was considered to be 0.7% in terms of Al atoms. In addition, when the IR measurement of the solid organoaluminum oxy compound was carried out, the IR spectrum showed 600 to 800 cm ⁻¹
Shows an absorption in the Al-O-Al atomic group, and 1220
The ratio of absorbance at cm ^-1 absorbance at (D ₁₂₂₀₎ and 1260 cm ^-1 and _{(D 1260) (D 1260 /} D 1220) was 0.053.
In addition, methane was generated by decomposition with water.

[Polymerization] To a 2-liter stainless steel autoclave sufficiently purged with nitrogen, 600 ml of toluene and 300 ml of 4-methyl-1-pentene were placed.
After heating, the temperature was raised to 50 ° C., and a toluene suspension of a benzene-insoluble organoaluminum oxy compound in toluene (0.44 mol-Al /
l) 0.11 ml and 1 ml of a toluene solution of triisobutylaluminum (1 mol-Al / l) were added. After the temperature was further raised to 75 ° C, 0.3 ml of a toluene solution of ethylene bis (indenyl) zirconium dichloride (0.0005 mol-Zr / l) was injected together with ethylene to initiate polymerization. The polymerization was carried out at 80 ° C. for 40 minutes at a total pressure of 8 kg / cm ² -G while continuously supplying ethylene, and the MFR was 14.0 g / 10 minutes, the density was 0.898 g / cm ³ , and w / ethylene in which n is 2.3
98.9 g of a 4-methyl-1-pentene copolymer was obtained.

Comparative Example 1 Polymerization was carried out in the same manner as in Example 1 except that the aluminoxane synthesized in Example 1 was used in an amount of 0.05 mg atom in terms of Al atom instead of the benzene-insoluble organoaluminum oxy compound. MF
R is 9.73 g / 10 min, density is 0.905 g / cm ³ , w /
55.1 g of an ethylene / 4-methyl-1-pentene copolymer having n of 2.3 was obtained.

Comparative Example 2 In the polymerization of Example 1, instead of the benzene-insoluble organic aluminum oxy compound, the aluminoxane synthesized in Example 1 was used in an amount of 0.5 mg atom in terms of Al atom, and triisobutylaluminum was not used. Was performed in the same manner as in Example 1, and the MFR was 35.6 g / 1.
0 minutes, a density of 0.897 g / cm ^3, ethylene-4-methyl-1-pentene copolymer w / n is 2.2 62.8
g was obtained.

Example 2 [Preparation of benzene-insoluble organoaluminum oxy compound] In a 400-ml glass flask sufficiently purged with nitrogen, spheres were separated with 134 ml of toluene and a 32-mesh sieve, and Al ₂ (SO ₄ ) _3. 10.9 g of 14H ₂ O was charged and suspended. Thereto, a toluene solution of aluminoxane (2.34 mol-Al
/ l) 100 ml were added. Subsequently, the temperature was raised to 80 ° C., and stirring was continued at that temperature for 7 hours. Thereafter, the aluminum sulfate compound was removed with a 80-mesh screen under a nitrogen atmosphere, and solid-liquid separation was further performed by filtration to obtain a benzene-insoluble organic aluminum oxy compound. When the concentration of aluminum dissolved in the filtrate was measured, the detection limit was 5 m.
g-Al / l or less.

When the solubility of the obtained Al compound in benzene at 60 ° C. was measured in the same manner as in Example 1, it was 0.3%.

The ratio of the absorbance at 1220 cm ^-1 and (D ₁₂₂₀₎ absorbance at 1260 cm ^-1 and _{(D 1260) (D 1260 /} D 1220) was 0.067.

[Polymerization] 250 ml of toluene was charged into a 500 ml glass autoclave sufficiently purged with nitrogen, and the temperature was raised to 65 ° C. while flowing propylene gas. Thereafter, 0.5 mmol of triisobutylaluminum, 0.5 mg atom of a benzene-insoluble organic aluminum oxy compound in terms of aluminum atom, and 0.005 mmol of ethylenebis (indenyl) zirconium dichloride were sequentially added to initiate polymerization. While supplying propylene gas continuously, under normal pressure,
When polymerization was carried out at 70 ° C. for 1 hour, [η] measured in decalin at 135 ° C. was 0.28 dl / g, and w / n was 1.9.
16.9 g of isotactic polypropylene was obtained.

Comparative Example 3 In the polymerization of Example 2, instead of the insoluble organoaluminum oxy compound of benzene, the toluene solution of the aluminoxane synthesized in Example 1 was used in an amount of 2.5 milligrams in terms of aluminum atoms, and triisobutylaluminum was used. The polymerization was carried out in the same manner as in Example 2 except that the polymerization was not performed. As a result, [η] was 0.14 dl / g, and w /
12.0 g of isotactic polypropylene having n of 1.9 was obtained.

Example 3 [Preparation of benzene-insoluble organoaluminum oxy compound] A 400 ml glass flask sufficiently purged with nitrogen was charged with 32.8 ml of toluene and 0.78 g of pulverized magnesium chloride hexahydrate to form a slurry. At room temperature, 25 ml of the toluene solution of aluminoxane (2.31 mol-Al / l) prepared in Example 1 was added thereto. Thereafter, the temperature was raised to 80 ° C., and stirring was continued at that temperature for 7 hours. After 7 hours, solid-liquid separation was performed by filtration to obtain a benzene-insoluble organic aluminum oxy compound. When the concentration of aluminum dissolved in the filtrate was measured, the detection limit (5 mg-Al /
l) It was the following.

When the solubility of the obtained Al compound in benzene at 60 ° C. was measured in the same manner as in Example 1, it was 0.3%.

[Polymerization] The polymerization was carried out in the same manner as in the polymerization of Example 1, except that the amount of triisobutylaluminum used was 0.25 mmol, and the benzene-insoluble organic aluminumoxy compound prepared above was used in an amount of 0.05 mg atom in terms of aluminum atom. MFR of 11.5 g / 10 min, density of 0.900 g / cm ³
And ethylene / 4-methyl-w / n is 2.3
93.3 g of 1-pentene copolymer was obtained.

Example 4 In the polymerization of Example 3, except that 1-octene was used in place of 4-methyl-1-pentene, ethylene bis (indenyl) zirconium dichloride was used in an amount of 7 × 10 ^-8 mol, and triisobutylaluminum was used in an amount of 1 mmol. Is performed in the same manner, the MFR is 8.94 g / 10 min, and the density is 0.896 g / cm ³
And 70.8 g of an ethylene / 1-octene copolymer having a w / n of 2.2 was obtained.

Example 5 In the polymerization of Example 3, tri-2-ethylhexyl aluminum was used instead of triisobutyl aluminum.
The same procedure was performed except that 0.5 mmol was used, and the MFR was 12.1 g /
10 minutes, density is 0.900 g / cm ³ , w / n is 2.4
Ethylene-4-methyl-1-pentene copolymer 9
0.5 g was obtained.

[Brief description of the drawings]

FIG. 1 is an IR spectrum of a benzene-insoluble organoaluminum oxy compound used in the present invention, and FIG. 2 is an IR spectrum of a conventionally known benzene-soluble organoaluminum compound. FIG. 3 is a flowchart illustrating the olefin polymerization method according to the present invention.

Claims (2)

(57) [Claims] [1] An Al component dissolved in benzene at 60 ° C.
10% or less in terms of Al atom, An organoaluminum oxy compound having an alkyloxyaluminum unit represented by the formula: [B] two ligands having a cyclopentadienyl skeleton, and two of the ligands having a cyclopentadienyl skeleton are lower A transition metal compound containing a transition metal selected from the group consisting of titanium, zirconium and hafnium bonded through an alkylene group, and [C] a formula R ⁶ _n AlX _3-n (where R ⁶ is carbon An olefin polymerization catalyst formed from an organoaluminum compound represented by the following formula (1): a hydrocarbon group of the formulas (1) to (12), X is a halogen, and n is from 1 to 3. 2. [A] The Al component dissolved in benzene at 60 ° C.
10% or less in terms of Al atom, An organoaluminum oxy compound having an alkyloxyaluminum unit represented by the formula: [B] two ligands having a cyclopentadienyl skeleton, and two of the ligands having a cyclopentadienyl skeleton are lower A transition metal compound containing a transition metal selected from the group consisting of titanium, zirconium and hafnium bonded through an alkylene group, and [C] a formula R ⁶ _n AlX _3-n (where R ⁶ is carbon Is a hydrocarbon group of the formulas (1) to (12), X is a halogen, and n is from 1 to 3). A method for polymerizing olefins.