JP2741922B2 - 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, and more particularly, has excellent polymerization activity, and has a narrow molecular weight distribution and a narrow composition distribution. The present invention relates to a novel catalyst for olefin polymerization capable of obtaining an olefin copolymer and a method for polymerizing olefin using the 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 [where R is cyclopentadienyl, C ₁ -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: [Wherein, R and n are defined the same as above] the presence of a catalyst comprising a cyclic aluminoxane represented by one α- olefin ethylene and C ₃ -C _12, or two or more 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 is R ⁰ -R ¹ or is bonded to represent —O—, and the aluminoxane compound represented by 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 and a weight average molecular weight of 36,400. And that a polyethylene containing 3.4% of a propylene component 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 that ethylene alone, or ethylene and an α-olefin having 3 or more carbon atoms, 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 1
In about 20 cyclic Aruminookisa or formula R (R-Al-O) n AlR 2 represented by an integer] [wherein, R is an alkyl group having 1 to 5 carbon atoms, the definition of n is above And a linear aluminoxa represented by the following formula: According to the publication, the polymer thus obtained has a polymerization average molecular weight of about 500 to about 1.4 million and a molecular weight distribution of 1.5 to 4.0.

JP-A-60-35008 discloses that, by using a catalyst system containing at least two kinds of metallocenes and aluminoxane, polyethylene or ethylene having a wide molecular weight distribution and an α-olefin of C _{3 to} C ₁₀ can be used. Is described as being produced. The publication describes that the copolymer has a molecular weight distribution (w / n) of 2 to 50.

A method for polymerizing an olefin using a catalyst formed from a mixed organoaluminum compound comprising a transition metal compound, an aluminoxane and an organoaluminum compound is disclosed in JP-A-60-260602 and JP-A-60-130604. 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, and JP-A-62-148491 teaches. The publication teaches that aluminoxane can be obtained by reacting an organoaluminum compound with a compound containing water of crystallization selected from the group consisting of magnesium compounds, nickel compounds and lanthanide compounds. 1963-5
JP-A-6507 and JP-A-63-56508 disclose that aluminum is produced by directly reacting water and an organoaluminum compound in an inert hydrocarbon solvent by using a high-speed high-breaking-force induction impeller or ultrasonic waves. It is taught that nooxane can be obtained.

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, the emergence of an aluminoxane-based organic aluminium compound having even better polymerization activity for α-olefins and capable of obtaining an olefin copolymer having a narrow molecular weight distribution and composition distribution is strongly desired. I have.

Aluminoxane compounds that have been used for conventionally known olefin polymerization are all recovered in benzene or in a state soluble in toluene, and the molecular weight is further measured by dissolving in benzene and measuring by a freezing point depression method. I was 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 organoaluminum oxo 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 uses an organoaluminum oxy compound, which was not known at all, as a component of a catalyst, has excellent catalytic activity, and obtains an olefin polymer having a narrow molecular weight distribution and composition distribution. It is an object of the present invention to provide an olefin polymerization catalyst that can be used and a method for polymerizing an olefin using the catalyst.

SUMMARY OF THE INVENTION The olefin polymerization catalyst according to the present invention is characterized in that [A] the Al component soluble in benzene at 60 ° C. is 10% or less in terms of Al atoms, (Wherein R ¹ is a hydrocarbon group having 1 to 12 carbon atoms), comprising an organoaluminum oxy compound having an alkyloxyaluminum unit represented by the formula: and [B] two ligands having a cyclopentadienyl skeleton , A transition metal compound containing a transition metal selected from the group consisting of titanium, zirconium and hafnium (excluding those bonded from the above ligands through lower alkylene groups). .

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 catalyst for olefin polymerization according to the present invention comprises [A] an organic aluminum oxy compound insoluble or hardly soluble in benzene, and [B] a transition metal compound containing a ligand having a cyclopentadienyl skeleton. An olefin copolymer having excellent polymerization activity for olefin polymerization and having a narrow molecular weight distribution and composition distribution can be obtained.

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 is formed from [A] a benzene-insoluble organic aluminum oxy compound and [B] a transition metal compound containing a ligand having a cyclopentadienyl skeleton.

[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, hot filtration was performed at 60 ° C., and the solid part separated on the filter was washed four times with 50 ml of benzene at 60 ° C., and 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 0.4 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 pestle 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) 1280cm ^-1 signed a maximum point in the vicinity of and around 1240cm ^-1,
This is referred to as base line L _1.

(B) Transmittance (T%) at the minimum absorption point near 1260 cm ^-1
When drawing a perpendicular line with wavenumber axis (horizontal axis) from the minimum point, the transmittance of the intersection of the baseline L ₁ the perpendicular (T
₀ %) and read the absorbance near ₁₂₆₀ cm ^-1 (D ₁₂₆₀ = log
Calculate T ₀ / 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 line is drawn to the wave number axis (horizontal axis), and the perpendicular line is read as the transmittance (T ′ ₀ %) of the intersection between the baseline L ₂ and this, and the absorbance (D ₁₂₂₀ ) around ₁₂₂₀ cm ⁻¹ is read.
_{= Log T '0 / T'} ) is calculated.

(E) D ₁₂₆₀ / D ₁₂₂₀ is calculated from these values.

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,
In a suspension of a hydrocarbon medium such as ceric chloride hydrate,
A method in which an organoaluminum compound such as trialkylaluminum is added and reacted to recover a hydrocarbon solution.

(2) A method in which an organic aluminum compound such as a trialkylaluminum is directly allowed to act on water vapor or water vapor such as ice in a medium such as benzene, toluene, ethyl ether, or tetrahydrofuran to recover 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 pro Mid,
Examples thereof include alkylaluminum halides such as diisobutylaluminum chloride, diethylaluminum hydrides such as diisobutylaluminum hydride, dialkylaluminum alkoxides such as dimethylaluminum methoxide and diethylaluminum ethoxide, and dialkylaluminum alitoxides such as diethylaluminum phenoxide.

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.

As the active hydrogen-containing compound used in the present invention, 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 are used. 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, 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 petroleum fractions such as gasoline, kerosene, and light oil, and aromatic hydrocarbons, aliphatic hydrocarbons, and 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% based on 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 an aluminoxane solution is brought into contact with water or a hydrocarbon solvent containing an active hydrogen-containing compound.

(2) A method of contacting aluminoxane with steam by blowing steam of water or an active hydrogen-containing compound into a solution of aluminoxane.

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

(4) Aluminoxane is mixed with a solution of an aluminoxane and a hydrocarbon suspension of a compound containing adsorbed water or a compound of water of crystallization or a hydrocarbon suspension of a compound on 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. The contact reaction between the organoaluminum compound and water which can use adsorbed water or the like is usually performed in a hydrocarbon solvent. The hydrocarbon solvent used at this time includes benzene, toluene, xylene, cumene,
Aromatic hydrocarbons such as cymene, pentane, hexane, heptane, octane, decane, dodecane, hexadecane,
Aliphatic hydrocarbons such as octadecane, cyclopentane,
Cyclohexane, cyclooctane, alicyclic hydrocarbons such as methylcyclohexane, gasoline, kerosene, petroleum fractions such as light oil or the above aromatic hydrocarbons, aliphatic hydrocarbons, halides of alicyclic hydrocarbons, especially chlorinated products, Hydrocarbon solvents such as bromides. In addition, ethers such as ethyl ether terahydrofuran can also 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 in which a hydrocarbon solution of organoaluminum is brought into contact with a hydrocarbon solvent containing water.

(2) A method in which water vapor is blown into a hydrocarbon solution of organic aluminum to bring the organic aluminum into contact with water vapor.

(3) A method of mixing a hydrocarbon solution of an organoaluminum and a hydrocarbon suspension of a compound containing adsorbed water or a compound containing water of crystallization and bringing the organic aluminum into contact with the adsorbed water or the water of crystallization.

(4) A method of contacting ice with a hydrocarbon solution of organoaluminum.

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 [A] organoaluminum 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 catalyst for olefin polymerization according to the present invention comprises the above-mentioned [A] benzene-insoluble organoaluminum oxy compound and the following [B] ligand having a cyclopentadienyl skeleton. And transition metal compounds.

The [B] transition metal compound used in the present invention has the following formula: ML _x (where M is a transition metal, L is a ligand coordinated to the transition metal, and at least one L is cyclopentadienyl) L is a ligand having a skeleton, and L 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, and x is a transition metal. It is a valence.) .

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 cyclopentane such as cyclopentadienyl group, methylcyclopentadienyl group, ethylcyclopentadienyl group, n-butylcyclopentadienyl group, dimethylcyclopentadienyl group and pentamethylcyclopentadienyl group Examples thereof include a dienyl group, an indenyl group, and a fluorenyl group.

One or more ligands having such a cyclopentadienyl skeleton are coordinated to the transition metal M, preferably two.

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.

When the transition metal compound containing a ligand having a [B] cyclopentadienyl skeleton used in the present invention is, for example, the valence of the transition metal is 4, more specifically, the compound represented by the formula R ² _k R ³ _l R ⁴ _m R ⁵ _n M ( _where M is zirconium, titanium, harnium or vanadium, R ² is a group having a cyclopentadienyl skeleton, and R ³ , R ⁴ and R ⁵ Is a group having a cyclopentadienyl skeleton, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, an alkoxy group, an aryloxy group, a halogen atom or hydrogen, k is an integer of 1 or more, and k + 1 + m + n = 4 ).

Hereinafter, specific examples of the transition metal compound containing a ligand having a [B] cyclopentadienyl skeleton in which M is zirconium will be described.

Bis (cyclopentadienyl) zirconium monochloride monohydride, bis (cyclopentadienyl) zirconium monopromide monohydride, bis (cyclopentadienyl) methyl zirconium hydride, bis (cyclopentadienyl) ethyl zirconium hydride, bis (Cyclopentadienyl) phenyl zirconium hydride, bis (cyclopentadienyl) benzyl zirconium hydride, bis (cyclopentadienyl) neopentyl zirconium hydride, bis (methylcyclopentadienyl) zirconium monochloride hydride, bis (indenyl) Zirconium monochloride hydride, bis (cyclopentadienyl) zirconium dichloride, bis (cyclopentadienyl) di Ruconium dipromide, bis (cyclopentadienyl) methyl zirconium monochloride, bis (cyclopentadienyl) ethyl zirconium monochloride, bis (cyclopentadienyl) cyclohexyl zirconium monochloride, bis (cyclopentadienyl) phenyl zirconium Monochloride, bis (cyclopentadienyl) benzylzirconium monochloride, bis (methylcyclopentadienyl) zirconium dichloride, bis (n-butylcyclopentadienyl) zirconium dichloride, bis (indenyl) zirconium dichloride, bis (indenyl) Zirconium dipromide, bis (cyclopentadienyl) zirconium dimethyl, bis (cyclopentadienyl) zirconium diphenyl, bis (cyclopentane (Enyl) zirconium dibenzyl, bis (cyclopentadienyl) zirconium methoxychloride, bis (cyclopentadienyl) zirconium ethoxycyclolide, bis (methylcyclopentadienyl) zirconium ethoxycyclolide, bis (cyclopentadienyl) zirconium phenoxycyclolide , Bis (fluorenyl) 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.

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

In the present invention, an olefin polymerization catalyst comprising the above-mentioned [A] benzene-insoluble organic aluminum oxy compound and [B] a transition metal compound containing a ligand having a cyclopentadienyl skeleton is used. To produce an olefin polymer.

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-pentene, 1-hexene, 4-methyl-
1-pentene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene, cyclopentene, cycloheptene, norbornel, 5-methyl-2-norbornene,
Examples thereof include tetracyclododecene, 2-methyl-1,4,5,8-dimethano-1,2,3,4,4a, 5,8,8a-octahydronafullerene.

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 any of a liquid-compatible polymerization method such as a solution polymerization and a 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
The transition metal compound containing a ligand having a [B] cyclopentadienyl skeleton is usually 10 ^-8 to 10 ^-3 mol / l.
Preferably, it is used in an amount of 10 ^-7 to 10 ^-4 mol / l.

The olefin polymerization catalyst according to the present invention, which is formed from the above-mentioned [A] benzene-insoluble organic aluminum oxy compound and [B] a transition metal compound containing a ligand having a cyclopentadienyl skeleton, is excellent. It has polymerization activity. Furthermore, the olefin polymerization catalyst according to the present invention can provide a polymer having a higher molecular weight than a conventionally known olefin polymerization catalyst formed from benzene-soluble aluminoxane and a metallocene-based compound.

Further, when an olefin is copolymerized using the olefin polymerization catalyst according to the present invention, an olefin copolymer having a narrow molecular weight distribution and a narrow composition distribution 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] a benzene-insoluble or hardly soluble organic aluminum oxy compound, and [B] a transition metal compound containing a ligand having a cyclopentadienyl skeleton. Therefore, it has excellent polymerization activity for olefin polymerization, and when olefin is polymerized using this catalyst, a high molecular weight polymer can be obtained, and an olefin copolymer having a narrow molecular weight distribution and composition distribution can be obtained. 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] 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 gradually added with a bipet.
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-
It was less than Al / l.

The benzene-insoluble organoaluminum oxy compound obtained above was placed in a 200 ml reactor equipped with a stirrer in an amount of 100 in terms of Al atoms.
Milligram atoms were added, and 100 ml of benzene was further added, followed by stirring and mixing at 60 ° C. for 6 hours. This suspension was subjected to hot filtration using a jacketed G5 glass filter while keeping the silicone oil poured into the jacket at 60 ° C., and further 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. As a result, 0.7 mmol of Al was detected. That is, the amount of the Al component of the organic aluminum oxy compound dissolved in benzene at 60 ° C. is
It was considered to be 0.7% in terms of Al atom. In addition, IR measurement of the above solid organoaluminum oxy compound showed absorption in the Al-O-Al atomic group at 600 to 800 cm ^-1 in the IR spectrum, and absorbance at ₁₂₂₀ cm ^-1 (D ₁₂₂₀ ). And the ratio of the absorbance at ₁₂₆₀ cm ^-1 (D ₁₂₆₀ ) (D
₁₂₆₀ / D ₁₂₂₀ ) was 0.053. In addition, methane was generated by decomposition with water.

[Polymerization] After 900 ml of 4-methyl-1-pentene was charged into a 2 l stainless steel autoclave sufficiently purged with nitrogen, the temperature was raised to 130 ° C., and the toluene suspension of the benzene-insoluble organic aluminum oxy compound prepared as described above was suspended in toluene. 1.14 ml of suspension (0.44 mol-Al / l) and bis (methylcyclopentadienyl)
Toluene solution of zirconium dichloride (0.001 mol-Z
r / l) 1 ml together with ethylene was injected to initiate polymerization. Total pressure 20 kg / cm ² − while continuously supplying ethylene
G, when polymerization was carried out at 140 ° C. for 30 minutes, [η] measured in decalin at 135 ° C. was 0.47 dl / g, and the density was 0.908 g.
/ cm ² , and 12.0 g of an ethylene / 4-methyl-1-pentene copolymer having a w / n of 2.4 was obtained.

Comparative Example 1 The procedure of Example 1 was repeated, except that the toluene solution of aluminoxane synthesized in Example 1 was used in an amount of 0.5 mg atom in terms of Al atom instead of the benzene-insoluble organoaluminum oxy compound in the polymerization of Example 1. As a result, [η] was 0.41 dl / g, the density was 0.910 g / cm ² , and w / n was 2.5.
8.4 g of a pentene copolymer 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 (2.3 mol-Al /
l) 100 ml was 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 mg-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 absorbance at 1220 cm ^-1 and (D _1220), the ratio of the absorbance at _{^{1260cm -1 (D 1260) (D}} 1260 / D 1220) was 0.067.

[Polymerization] Polymerization was carried out in the same manner as in Example 1 except that the benzene-insoluble organic aluminum oxy compound prepared above was used. As a result, [η] was 0.49 dl / g, and the density was 0.907 g.
/ cm ² , and 10.8 g of an ethylene / 4-methyl-1-pentene copolymer having a w / n of 2.6 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 a toluene solution of aluminoxane (2.31 mol-Al / l) prepared in the same manner as in Example 1 was added thereto. Thereafter, the temperature was raised to 80 ° C., and stirring was continued at that temperature for 7 hours. 7
After a period of time, 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, it was below the detection limit (5 mg-Al / l).

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] Polymerization was performed in the same manner as in Example 1 except that the benzene-insoluble organoaluminum oxy compound prepared above was used. [Η] was 0.46 dl / g, and the density was 0.907 g / cm ³ . , Ethylene-4-methyl-1- having a w / n of 2.5
11.3 g of a pentene copolymer was obtained.

Examples 4 to 6 Polymerization was carried out in the same manner as in Example 1 except that the transition metal compounds described in Table 1 were used.

 Table 1 shows the results.

[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, (Wherein R ¹ is a hydrocarbon group having 1 to 12 carbon atoms), comprising an organoaluminum oxy compound having an alkyloxyaluminum unit represented by the formula: and [B] two ligands having a cyclopentadienyl skeleton And a transition metal compound containing a transition metal selected from the group consisting of titanium, zirconium and hafnium (excluding those in which the above ligand is bonded via a lower alkylene group). 2. [A] The Al component dissolved in benzene at 60 ° C.
10% or less in terms of Al atom, (Wherein R ¹ is a hydrocarbon group having 1 to 12 carbon atoms), comprising an organoaluminum oxy compound having an alkyloxyaluminum unit represented by the formula: and [B] two ligands having a cyclopentadienyl skeleton , A transition metal compound containing a transition metal selected from the group consisting of titanium, zirconium and hafnium (excluding those in which the above ligand is bonded via a lower alkylene group). A method for polymerizing an olefin, comprising polymerizing or copolymerizing the olefin in the presence.