JP2781245B2 - Method for producing ethylene polymer composition - Google Patents

Description

Description: TECHNICAL FIELD OF THE INVENTION The present invention relates to a method for producing an ethylene-based polymer composition, and more particularly to a method for producing an ethylene-based polymer composition by a multistage polymerization method. Nevertheless, the present invention relates to a method for producing an ethylene-based polymer composition having a small amount of a hydrocarbon solvent-soluble component, and thus having excellent blocking resistance and excellent heat resistance.

Technical Background of the Invention In recent years, as a new Ziegler-type olefin polymerization catalyst, a method for producing an olefin polymer using a catalyst comprising a zirconocene compound and an aluminoxane has been disclosed in
Nos. -19309, 60-35007 and 61-221208, and according to these publications, it is possible to obtain an ethylene polymer having a narrow molecular weight distribution and a narrow composition distribution and excellent transparency. Has been reported to be However, polymers obtained by using the above-mentioned olefin polymerization catalysts, particularly copolymers, have low melting points and poor heat resistance. Therefore, improvement in heat resistance is desired for some applications.

On the other hand, an ethylene copolymer obtained using a titanium catalyst system comprising a titanium catalyst and an organoaluminum compound has excellent heat resistance, but when the density is reduced, the hydrocarbon solvent soluble content is large, and the blocking resistance is high. There was a problem that it was inferior.

Object of the Invention The present invention has been made in view of the prior art as described above, and provides a method for producing an ethylene-based polymer composition having excellent blocking resistance and heat resistance while maintaining original excellent properties. It is intended to provide.

SUMMARY OF THE INVENTION The method for producing an ethylene-based polymer composition according to the present invention comprises: a polymerization step (a): a transition metal compound [A] containing a ligand having a cycloalkadienyl skeleton and an organic aluminum oxy compound [B]. Using an olefin polymerization catalyst [I] comprising ethylene and another α-olefin, having a density of 0.91 g / cm ³ or less and an intrinsic viscosity [η] of 0.5 to 6 dl / g. A step of forming a certain ethylene-based copolymer [I], and a polymerization step (b): a titanium catalyst component [C] containing titanium, magnesium and halogen as essential components, an organic aluminum compound [D] and / or an organic aluminum Olefin polymerization catalyst [I] comprising oxy compound [E]
Using I], ethylene or ethylene and another α-olefin are polymerized or copolymerized to have a density higher than that of the ethylene copolymer [I] and an intrinsic viscosity of 0.5 to 6 dl.
/ g of the ethylene-based polymer [II], the polymerization step (b) is performed in the presence of the obtained ethylene-based copolymer [I]. ) Or the polymerization step (b), and then the polymerization step (a) in the presence of the obtained ethylene polymer [II]. The density is 0.87 to 0.93 g / cm ³ , and the intrinsic viscosity [η] is obtained by performing the polymerization so that the ethylene polymer [II] is in a ratio of 10 to 1000 parts by weight with respect to 100 parts by weight of the combined [I]. Is characterized by obtaining an ethylene polymer composition having a ratio of 0.5 to 6 dl / g.

According to the method for producing an ethylene-based polymer composition according to the present invention, an ethylene-based polymer having a low density and excellent blocking resistance and heat resistance can be obtained.

DETAILED DESCRIPTION OF THE INVENTION Hereinafter, the method for producing the ethylene polymer composition according to the present invention will be specifically described.

1 (a) and 1 (b) are explanatory views showing the steps for producing the ethylene-based polymer composition according to the present invention.

The method for producing the ethylene-based polymer composition according to the present invention,
It comprises a polymerization step (a) and a polymerization step (b).

In the polymerization step (a), an olefin polymerization catalyst [I] comprising a transition metal compound [A] containing a ligand having a cycloalkadienyl skeleton and an organic aluminum oxy compound [B] is used.

First, the transition metal compound [A] containing a ligand having a cycloalkadienyl skeleton will be described.

A transition metal compound containing a ligand having a cycloalkadienyl skeleton is represented by the formula ML _x (where M is a transition metal, L is a ligand that coordinates to the transition metal, and at least one L Is a ligand having a cycloalkadienyl skeleton, and when at least two or more ligands having a cycloalkadienyl skeleton are included, the ligand having at least two cycloalkadienyl skeletons is an alkylene L may be bonded via a substituted alkylene group, a silylene group or a substituted silylene group, and L other than a ligand having a cycloalkadienyl skeleton is a hydrocarbon group having 1 to 12 carbon atoms, an alkoxy group, an aryloxy group. Group, halogen or hydrogen, and x is the valence of the transition metal.)

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 cycloalkadienyl skeleton,
For example, alkyl-substituted cyclopentane such as cyclopentadienyl group, methylcyclopentadienyl group, ethylcyclopentadienyl group, t-butylcyclopentadienyl group, dimethylcyclopentadienyl group and pentamethylcyclopentadienyl group Examples thereof include a dienyl group, an indenyl group, and a fluorenyl group.

The ligand having a cycloalkadienyl skeleton as described above may be coordinated to two or more transition metals. In this case, the ligand having at least two cycloalkadienyl skeletons is They may be bonded via an alkylene group, a substituted alkylene group, a silylene group, or a substituted silylene group.

Examples of the alkylene group include a methylene group, an ethylene group, a trimethylene group, and a tetramethylene group. Examples of the substituted alkylene group include an isopropylidene group and a tetramethylethylene group, and examples of the substituted silylene group include a dimethylsilylene group. , Ethylmethylsilylene group, diphenylsilylene group and the like.

The ligand other than the ligand having a cycloalkadienyl 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.

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

Bis (cyclopentadienyl) zirconium monochloride monohydride, bis (cyclopentadienyl) zirconium monobromide monohydride, bis (cyclopentadienyl) methylzirconium hydride, bis (cyclopentadienyl) ethylzirconium 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 monohydride, bis (cyclopentadienyl) zirconium dichloride, bis (cyclopentadienyl) ) Zirconium dibromide, 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 (dimethylcyclopentadienyl) zirconium dichloride, bis (n-butylcyclopentadienyl) zirconium dichloride, Bis (indenyl) zirconium dichloride, bis (indenyl) zirconium dibromide, bis (cyclopentadienyl) zirconium dimethyl, bis ( Clopentadienyl) zirconium diphenyl, bis (cyclopentadienyl) zirconium dibenzyl, bis (cyclopentadienyl) zirconium methoxychloride, bis (cyclopentadienyl) zirconium ethoxycyclolide, bis (methylcyclopentadienyl) zirconium Ethoxycyclolide, bis (cyclopentadienyl) zirconium phenoxycyclolide, bis (fluorenyl) zirconium dichloride, ethylenebis (indenyl) dimethylzirconium, ethylenebis (indenyl) diethylzirconium, ethylenebis (indenyl) diphenylzirconium monochloride, ethylenebis ( Indenyl) methyl zirconium monochloride, ethylenebis (indenyl) ethyl zirconium monochloride, d Lenbis (indenyl) methylzirconium monobromide, ethylenebis (indenyl) zirconium dichloride, ethylenebis (indenyl) zirconium dibromide, ethylenebis (4,5,6,7-tetrahydro-1-indenyl) dimethylzirconium, ethylenebis (4 , 5,6,7-Tetrahydro-1-indenyl) methylzirconium monochloride, ethylenebis (4,5,6,7-tetrahydro-1-indenyl) zirconium dichloride, ethylenebis (4,5,6,7-tetrahydro -1-indenyl) zirconium dibromide, ethylenebis (4-methyl-1-indenyl) zirconium dichloride, ethylenebis (5-methyl-1-indenyl) zirconium dichloride, ethylenebis (6-methyl-1-indenyl) zirconium dichloride , D Lenbis (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.

Isopropylidene (cyclopentadienyl-fluorenyl) zirconium dichloride isopropylidenebis (indenyl) zirconium dichloride dimethylsilylenebis (cyclopentadienyl) zirconium dichloride dimethylsilylenebis (methylcyclopentadienyl) zirconium dichloride dimethylsilylenebis (indenyl) zirconium Dichloride A transition metal compound in which zirconium metal is replaced with titanium metal, hafnium metal or vanadium metal in the above zirconium compound can also be used.

Next, the organic aluminum oxy compound [B] will be described.

The organic aluminum oxy compound [B] may be a conventionally known aluminoxane, or may be a benzene-insoluble organic aluminum oxy compound found by the present inventors.

The aluminoxane as described above 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-. Trialkylaluminum such as butylaluminum, tritert-butylaluminum, tripentylaluminum, trihexylaluminum, trioctylaluminum, tridelaluminum, tricyclohexylaluminum, tricyclooctylaluminum, dimethylaluminum chloride, diethylaluminum chloride, diethylaluminum bromide , Dialkyl aluminum halides such as diisobutyl aluminum chloride, Dialkyl aluminum hydrides such as aluminum hydride and diisobutyl aluminum hydride; dialkyl aluminum alkoxides such as dimethyl aluminum methoxide and diethyl aluminum ethoxide; and dialkyl aluminum aryloxides such as diethyl aluminum phenoxide.

Of these, trialkyl aluminum is particularly preferred.

Also, iso organoaluminum compound represented by the general formula _{(i-C 4 H 9)} x Al y (C 5 H 10) z (x, y, z are each a positive number, which is a z ≧ 2x) represented by Prenyl aluminum 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, toctadecane, cyclopentane, cyclohexane, cyclooctane, methylcyclopentane, etc. And petroleum fractions such as gasoline, kerosene and light oil, and ethers such as ethyl ether and tetrahydrofuran. Among these solvents, aromatic hydrocarbons are particularly preferred.

The benzene-insoluble organoaluminum oxy compound used in the present invention has an Al component soluble in benzene at 60 ° C. of not more than 10%, preferably not more than 5%, particularly preferably not more than 2% in terms of Al atom. Insoluble or poorly soluble.

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%).

Analysis of the benzene-insoluble organoaluminum oxy compound as described above by infrared spectroscopy (IR) shows that
1220cm absorbance at around ^-1 (D _1220), the ratio of the absorbance at around _{^{1260cm -1 (D 1260) (D}} 1260 / D 1220) , the
0.09 or less, preferably 0.08 or less, particularly preferably 0.04 to 0.07
Is desirably within the range.

The infrared spectroscopic analysis of the organic aluminum 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
The IR spectrum is shown in FIG.

From the IR spectrum thus obtained, D ₁₂₆₀ / D
Request _1220, this D _1260/1220 value 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%),} 1260 -1 vicinity of absorbance (D ₁₂₆₀ = log 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 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 absorbance near ₁₂₂₀ cm ^-1 (D ₁₂₂₀ = log)
T ′ ₀ / T ′) is calculated.

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

FIG. 3 shows the IR spectrum of a conventionally known benzene-soluble organic aluminum oxy compound. As can be seen from FIG. 3, 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 D ₁₂₆₀ / D ₁₂₂₀ value.

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 a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a pentyl group, a hexyl group, an octyl group, a decyl group, a cyclohexyl group, a cyclooctyl group, or the like. . Of these, a methyl group and an ethyl group are preferable, and a methyl group is particularly preferable.

This benzene-insoluble organoaluminum oxy compound is 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, a method for producing the benzene-insoluble organic aluminum oxy compound as described above will be specifically described.

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

As the active hydrogen-containing compound, alcohols such as methanol, ethanol, n-propanol and isopropanol, 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, and hexane, an ether solvent such as tetrahydrofuran, an amine solution 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, or steam 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% 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 gram atoms / preferably 1 × 10 ^{-2 to} 3 gram atoms /, and the concentration of water in the reaction system is usually 2 × 10 ^{-4 to} 5 mol / preferably. 2x
The concentration is preferably 10 ^{-3 to} 3 mol /.

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 can also be obtained directly by bringing the above-mentioned organoaluminum into contact 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 organic aluminum compound in the reaction system is usually 1 × 10 ^{−3 to} 5 g atom /
Preferably, the concentration is in the range of 1 × 10 ^{-2 to} 3 g atom /, and the concentration of water in the reaction system is usually 1 × 10 ^-2.
The concentration is preferably ^{-3 to} 5 mol / preferably 1 × 10 ^{-2 to} 3 mol /. At this time, the amount of the organic aluminum atoms dissolved in the reaction system is desirably 20% or less, preferably 10% or less, more preferably 0 to 5% based on all the organic aluminum atoms.

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 carried out at a temperature of -100 to 150C, preferably -70 to 100C, and more preferably -50 to 80C. The reaction time varies greatly depending on the reaction temperature, but is usually about 1 to 200 hours, preferably about 2 to 100 hours.

Further, the olefin polymerization catalyst used in the present invention may contain an organoaluminum compound as necessary.

Examples of such an organoaluminum compound include R _n ⁶ AlX _3-n (wherein R ⁶ is a hydrocarbon group having 1 to 12 carbon atoms, X is halogen or hydrogen, and n is 1 to 3 Can be exemplified.

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, cyclopentyl group, cyclohexyl group, phenyl group, tolyl group and the like.

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

Trimethyl aluminum, triethyl aluminum,
Trialkylaluminums such as triisopropylaluminum, triisobutylaluminum, trioctylaluminum, and tri-2-ethylhexylaluminum.

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, butylaluminum sesquichloride, and ethylaluminum sesquibromide.

Alkylaluminum dihalides such as methylaluminum dichloride, ethylaluminum dichloride, isopropylaluminum dichloride and ethylaluminum dibromide;

Alkyl aluminum hydrides such as diethyl aluminum hydride and diisobutyl aluminum hydride.

R ⁶ _n AlY _3-n (wherein R
⁶ is as defined above, Y is -OR ⁷ group, -OSiR ⁸ ₃ group, -OA
lR ⁹ ₂ group, -NR ¹⁰ ₂ group, -SiR ¹¹ ₃ group or Wherein n is 1-2, R ⁷ , R ⁸ , R ⁹ and R ¹³ are a methyl group, an ethyl group, an isopropyl group, an isobutyl group, a cyclohexyl group, a phenyl group, etc., and R ¹⁰ is hydrogen,
Examples include a methyl group, an ethyl group, an isopropyl group, a phenyl group, and a trimethylsilyl group, and R ¹¹ and R ¹² are a methyl group, an ethyl group, and the like. ) Can also be used.

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

_{^{(I) R 6 n Al (}} OR 7) 3-n dimethylaluminum methoxide, diethylaluminum ethoxide and diisobutylaluminum _{^{methoxide, (ii) R 6 n Al}} (OSi R 8 3) 3-n Et 2 Al ( _{OSi Me 3) (iso-Bu} ) 2 Al (OSi Me 3) (iso-Bu) such as _{2 Al (OSi Et 3),} (iii) R 6 n Al (OAl R 9 2) 3-n Et 2 Al OAl Et ₂ (iso-Bu) ₂ Al OAl (iso-Bu) _2, etc., (iv) R ⁶ _n Al (NR ¹⁰ ₂ ) _3-n Me ₂ Al NEt ₂ Et ₂ Al NHMe Me ₂ Al NHEt Et ₂ Al N such as _{(Me 3 Si) 2 (iso} -Bu) 2 Al n (Me 3 Si) 2, etc. _{^{(v) R 6 n Al (}} Si R 11 3) 3-n (iso-Bu) 2 Al Si Me 3, Organoaluminum compounds mentioned above, R ⁶ ₃ A
l, can be exemplified ^{_{R 6 n Al (OR 7)}} 3-n, an organic aluminum compound represented by ^{_{R 6 n Al (OAlR 9 2}} ) 3-n Suitable examples, in particular R ⁶ is located at isoalkyl group , N = 2 are preferred. These organoaluminum compounds can be used as a mixture of two or more kinds.

The olefin polymerization catalyst as described above can 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.

In the polymerization step (a), ethylene and another α-olefin are copolymerized using the olefin polymerization catalyst [I] as described above, and the density is 0.91 g / cm ³ or less, preferably 0.86 g / cm ³ or less.
It forms an ethylene copolymer [I] having an intrinsic viscosity of 0.905 g / cm ^3, more preferably 0.87 to 0.90 g / cm ³ , and an intrinsic viscosity “η” of 0.5 to 6 dl / g, preferably 0.7 to 4 dl / g.

Α-olefins other than ethylene that can be used in the polymerization step (a) of the present invention include α-olefins having 3 to 20 carbon atoms.
Olefins such as propylene, 1-butene, -1
Pentene, 1-hexene, 4-methyl-1-pentene,
1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-exadecene, 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, styrene, vinylcyclohexane, diene and the like can be used.

This polymerization step (a) can be carried out by any of a liquid phase polymerization method such as solution polymerization and suspension polymerization or a gas phase polymerization method. Of these, solution polymerization is particularly preferred.

The polymerization temperature of the olefin using such an olefin polymerization catalyst [I] is usually in the range of −50 to 200 ° C., preferably 0 to 150 ° C. The polymerization pressure is usually from normal pressure to 100
kg / cm 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. 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.

Using the olefin polymerization catalyst [I] as described above,
In conducting olefin polymerization, a transition metal compound [A] containing a ligand having a cycloalkadienyl skeleton
Is usually from 10 ^-15 to 1 mmol, preferably from 10 ^{-4 to} 0.1 mmol, per reaction volume, and usually from 0.01 to 10 mmol, preferably from 10 to 10 mmol, for the organoaluminum oxy compound [B].
In amounts of 0.02 to 5 mmol, the organoaluminum compound is
Usually, it is desirable to use it in an amount of 0 to 10 mmol, preferably 0.1 to 5 mmol.

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

In the polymerization step (b), an olefin polymerization catalyst [II] comprising a titanium catalyst component [C] containing titanium, magnesium and halogen as essential components, and an organic aluminum compound [D] and / or an organic aluminum oxy compound [E]. ] Is used.

First, the titanium catalyst component [C] containing titanium, magnesium and halogen as essential components will be described. The titanium catalyst component [C] contains titanium, magnesium and halogen as essential components and further contains an electron donor as necessary. doing.

Such a titanium catalyst component [C] is prepared by contacting the following magnesium compound, titanium compound and, if necessary, an electron donor.

In the present invention, the titanium compound used for preparing the titanium catalyst component [C] includes, for example, Ti (OR) _g X _4-g
(R is a hydrocarbon group, X is a halogen atom, and 0 ≦ g ≦ 4). More specifically, titanium tetrahalides such as TiCl ₄ , TiBr ₄ , and TiI ₄ ; Ti (OCH ₃ ) Cl ₃ , Ti (Oe ₂ H ₅ ) Cl ₃ , and Ti (On-C ₄ H ₉ ) Cl ₃ , Ti (OC ₂ H ₅ ) Br ₃ , Ti (OisoC ₄ H ₉ ) Br _3, etc .; trihalogenated alkoxytitanium; Ti (OCH ₃ ) ₂ Cl ₂ , Ti (OC ₂ H ₅ ) ₂ Cl ₂ , Ti ( _{On-C 4 H 9) 2} Cl 2, Ti (OC 2 H 5) 2 dihalogenated dialkoxy titanium, such as _{Br 2; Ti (OCH 3)} 3 Cl, Ti (OC 2 H 5) 3 Cl, Ti (On Monohalogenated trialkoxy titanium such as -C ₄ H ₉ ) ₃ Cl, Ti (OC ₂ H ₅ ) ₃ Br; Ti (OCH ₃ ) ₄ , Ti (OC ₂ H ₅ ) ₄ , Ti (On-C ₄ H) _{9) 4 Ti (Oiso-C} 4 H 9) 4 Ti (O-2- _ethylhexyl) such as tetra-alkoxy titanium such as ₄ can be cited.

These titanium compounds may be used alone or in combination of two or more. Further, these titanium compounds may be diluted with a hydrocarbon compound or a halogenated hydrocarbon compound.

In the present invention, examples of the magnesium compound used for preparing the titanium catalyst component [C] include a magnesium compound having a reducing property and a magnesium compound having no reducing property.

Here, examples of the magnesium compound having a reducing property include a magnesium compound having a magnesium-carbon bond or a magnesium-hydrogen bond. Specific examples of such reducing magnesium compounds include dimethylmagnesium, diethylmagnesium, dipropylmagnesium, dibutylmagnesium, diamylmagnesium, dihexylmagnesium, didecylmagnesium, ethylmagnesiumchloride, propylmagnesiumchloride, and butyl. Examples include magnesium chloride, hexyl magnesium chloride, amyl magnesium chloride, butylethoxy magnesium, ethyl butyl magnesium, octyl butyl magnesium, butyl magnesium halide, and the like. These magnesium compounds can be used alone or may form a complex compound with an organic aluminum compound described later. These magnesium compounds may be liquid or solid.

Specific examples of non-reducing magnesium compounds include magnesium halides such as magnesium chloride, magnesium bromide, magnesium iodide, and magnesium fluoride; methoxy magnesium chloride, ethoxy magnesium chloride, isopropoxy magnesium chloride, butoxy chloride. Alkoxy magnesium halides such as magnesium and octoxy magnesium chloride; alkoxy magnesium halides such as phenoxy magnesium chloride and methylphenoxy magnesium chloride; alkoxy such as ethoxy magnesium, isopropoxy magnesium, butoxy magnesium, n-octoxy magnesium and 2-ethylhexoxy magnesium Magnesium; allyloximers such as phenoxymagnesium and dimethylphenoxymagnesium Neshiumu; magnesium laurate, such as carboxylic acid salts of magnesium such as magnesium stearate and the like.

The non-reducing magnesium compound may be a compound derived from the above-described reducing magnesium compound or a compound derived during the preparation of the catalyst component. In order to derive a non-reducing magnesium compound from a reducing magnesium compound, for example, a reducing magnesium compound is converted to a polysiloxane compound, a halogen-containing silane compound, a halogen-containing aluminum compound, an ester, an alcohol, or the like. What is necessary is just to contact with a compound.

In the present invention, in addition to the magnesium compound having a reducing property and the aluminum compound having no reducing property, a magnesium compound is a complex compound of the magnesium compound and another metal, a double compound or another metal compound. May be used. Further, a mixture of two or more of the above compounds may be used.

In the present invention, among these, a magnesium compound having no reducing property is preferable, and a halogen-containing magnesium compound is particularly preferable. Among these, magnesium chloride, alkoxymagnesium chloride, and allyloxymagnesium chloride are preferably used.

In preparing the titanium catalyst component [C], it is preferable to use an electron donor, and examples of the electron donor include alcohols, amines, amides, ethers, and ketones.
Esters, nitriles, phosphines, stippins,
Examples thereof include arsines, phosphoramides, thioethers, thioesters, acid anhydrides, acid halides, aldehydes, alcoholates, alkoxy (aryloxy) silanes, and organic acids. Of these, alcohols, amines, ethers, esters, acid anhydrides, alkoxy (aryloxy) silanes, and organic acids are preferably used.

The titanium catalyst component [C] can be produced by contacting a magnesium compound (or metallic magnesium) as described above, a titanium compound and, if necessary, an electron donor. To produce the titanium catalyst component, a known method for preparing a highly active titanium catalyst component from a magnesium compound, a titanium compound, and, if necessary, an electron donor can be employed. The above components may be brought into contact with each other in the presence of another reaction reagent such as silicon, phosphorus, and aluminum.

The production method of these titanium catalyst components will be briefly described below with several examples.

In the following description of the method for producing the titanium catalyst component [C], an example in which an electron donor is used will be described. However, the electron donor is not necessarily used.

(1) A method of reacting a magnesium compound or a complex compound comprising a magnesium compound and an electron donor with a titanium compound in a liquid phase. In this reaction, each component may be pretreated with an electron donor and / or a reaction auxiliary such as an organoaluminum compound or a halogen-containing silicon compound. In this method, the electron donor is used at least once.

(2) a liquid magnesium compound having no reducing property;
A method of reacting a liquid titanium compound in the presence of an electron donor to precipitate a solid magnesium-titanium composite.

(3) A method in which a titanium compound is further reacted with the reaction product obtained in (2).

(4) The reaction product obtained in (1) or (2)
A method in which an electron donor and a titanium compound are further reacted.

(5) A solid obtained by pulverizing a magnesium compound or a complex compound comprising a magnesium compound and an electron donor in the presence of a titanium compound is treated with any of a halogen, a halogen compound and an aromatic hydrocarbon. Method. In this method, a magnesium compound or a complex compound comprising a magnesium compound and an electron donor may be ground in the presence of a grinding aid or the like. Alternatively, a magnesium compound or a complex compound composed of a magnesium compound and an electron donor may be ground in the presence of a titanium compound, pre-treated with a reaction aid, and then treated with a halogen or the like. In addition, examples of the reaction assistant include an organic aluminum compound and a halogen-containing silicon compound. In this method, an electron donor is used at least once.

(6) A method of treating the compound obtained in the above (1) to (4) with a halogen, a halogen compound or an aromatic hydrocarbon.

(7) A method of contacting a reaction product of a metal oxide, dihydrocarbylmagnesium and a halogen-containing alcohol with an electron donor and a titanium compound.

(8) A method in which a magnesium compound such as a magnesium salt of an organic acid, alkoxymagnesium, or aryloxymagnesium is reacted with an electron donor, a titanium compound and / or a halogen-containing hydrocarbon.

(9) magnesium compound and alkoxytitanium and / or
Alternatively, a method comprising reacting a catalyst component in a hydrocarbon solution containing at least an electron donor such as an alcohol or an ether with a halogen-containing compound such as a titanium compound and / or a halogen-containing silicon compound.

(10) A method in which a liquid magnesium compound having no reducing property is reacted with an organoaluminum compound to precipitate a solid magnesium-aluminum complex, and then a titanium compound is reacted.

Among the methods for adjusting the titanium catalyst component [C] described in the above (1) to (10), the methods (1) to (4) and (10) are preferably used.

Furthermore, a mixed solution of a liquid magnesium compound and a titanium compound having no reducing property can also be used.

The amount of each component used when preparing the titanium catalyst component [C] varies depending on the preparation method and cannot be specified unconditionally.
Per mole, the electron donor is about 0.01 to 20 moles, preferably 0.1 to 20 moles.
In an amount of from 05 to 10 mol, the titanium compound is used in an amount of about 0.01 to 500 mol, preferably 0.05 to 300 mol.

The titanium catalyst component thus obtained contains magnesium, titanium and halogen and, if necessary, an electron donor as essential components.

In this titanium catalyst component [C], halogen / titanium (atomic ratio) is about 4 to 200, preferably about 5 to 100, and the electron donor / titanium (molar ratio) is about 0.1 to 50,
Preferably, it is about 0.2 to about 25, and the magnesium / titanium (atomic ratio) is about 1 to 100, preferably about 2 to 50.

When the titanium catalyst component [C] is in a solid form, it contains a magnesium halide having a small crystal size as compared with a commercially available magnesium halide, and usually has a specific surface area of about 10 m ² / g or more, preferably about 30 m ² / g or more. 10001000 m ² / g, more preferably about 50-800 m ² / g. The composition of the solid titanium catalyst component [C] does not substantially change by washing with hexane since the above components are combined to form a catalyst component.

The method for preparing such a highly active titanium catalyst component [C] is described in, for example, JP-A-50-108385 and JP-A-50-108385.
No. 126590, No. 51-20297, No. 51-28189, No. 51-64586, No. 51-2885, No. 51-136
No. 625, No. 52-87489, No. 52-100596,
No. 52-147688, No. 52-104593, No. 53-2580
No. 53-40093, No. 53-40094 and No. 53
No. 43094, No. 55-135102, No. 55-135103, No. 55-152710, No. 56-811, No. 56-1
No. 1908, No. 56-18606, No. 58-83006,
JP-A-58-138705, JP-A-58-138706, JP-A-58-1387
No. 07, 58-138708, 58-138709,
JP-A-58-138710, JP-A-58-138715, JP-A-60-2340
No. 4, No. 60-195108, No. 61-21109,
It is disclosed in JP-A-61-37802 and JP-A-61-37803.

Usually, the titanium catalyst component [C] has an ethylene polymerization activity of 200 g-polymer / mmol-Ti × h × atm, preferably 500 g-polymer /
Desirably, it is expressed as mmol-Ti × h × atm or more.

As the organoaluminum compound [D] used in the present invention, for example, R _n ⁶ Al X _3-n (wherein, R ⁶ has 1 to 12 carbon atoms)
X is a halogen or hydrogen;
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, cyclopentyl group, cyclohexyl group, phenyl group, tolyl group and the like.

As such an organoaluminum compound [D],
Specifically, the following compounds are used.

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, butylaluminum sesquichloride, and ethylaluminum sesquibromide.

Alkylaluminum dihalides such as methylaluminum dichloride, ethylaluminum dichloride, isopropylaluminum dichloride and ethylaluminum dibromide;

Alkyl aluminum hydrides such as diethyl aluminum hydride and diisobutyl aluminum hydride.

Further, as the organic aluminum compound [D], R ⁶ _n Al Y
_3-n (wherein R ⁶ is the same as above, Y is —OR ⁷ group, —OS
i R ⁸ ₃ group, -OAlR ⁹ ₂ group, -NR ¹⁰ ₂ group, -Si R ¹¹ ₃ group or Wherein n is 1-2, R ⁷ , R ⁸ , R ⁹ and R ¹³ are a methyl group, an ethyl group, an isopropyl group, an isobutyl group, a cyclohexyl group, a phenyl group, etc., and R ¹⁰ is hydrogen,
Examples include a methyl group, an ethyl group, an isopropyl group, a phenyl group, and a trimethylsilyl group, and R ¹¹ and R ¹² are a methyl group, an ethyl group, and the like. ) Can also be used.

As such an organoaluminum compound [D],
Specifically, the following compounds are used.

_{^{(I) R 6 n Al (}} OR 7) 3-n dimethylaluminum methoxide, diethylaluminum ethoxide and diisobutylaluminum _{^{methoxide, (ii) R 6 n Al}} (OSi R 8 3) 3-n Et 2 Al ( _{OSi Me 3) (iso-Bu} ) 2 Al (OSi Me 3) (iso-Bu) such as _{2 Al (OSi Et 3),} (iii) R 6 n Al (OAl R 9 2) 3-n Et 2 Al OAl Et ₂ (isO-Bu) ₂ Al OAl (iso-Bu) _2, etc., (iv) R ⁶ _n Al (NR ¹⁰ ₂ ) _3-n Me ₂ Al NEt ₂ Et ₂ Al NHMe Me ₂ Al NHEt Et ₂ Al N such as _{(Me 3 Si) 2 (iso} -Bu) 2 Al n (Me 3 Si) 2, etc. _{^{(v) R 6 n Al (}} Si R 11 3) 3-n (iso-Bu) 2 Al Si Me 3, As the organoaluminum compound [D] as described above,
^{_{R 6 3 Al, R 6 n}} Al (OR 7) 3-n, R 6 n Al (OAl R 9 2) can be exemplified organoaluminum compounds represented by _3-n suitable examples, in particular R ⁶ Preferred is an isoalkyl group wherein n = 2. These organoaluminum compounds are
Two or more kinds can be used as a mixture.

As the organic aluminum oxy compound [E], the same compound as the organic aluminum oxy compound [B] used in the polymerization step (a) is used.

When performing the polymerization step (b), in addition to the titanium catalyst component [C] as described above and the organic aluminum compound [D] and / or the organic aluminum oxy compound [E], the electron donor as described above. An olefin polymerization catalyst [II] containing

In the polymerization step (b), using the olefin polymerization catalyst [II] as described above, ethylene is homopolymerized, or ethylene and another α-olefin are copolymerized. The density is higher than the above-mentioned ethylene-based copolymer [I] to be formed, preferably the density is 0.90 to 0.94.
More preferably g / cm ³ was 0.91~0.93g / cm ^3, and an intrinsic viscosity of 0.5~6dl / g preferably forms an ethylene-based polymer is a 0.7~4dl / g [II]. The ethylene-based polymer [II] has an n-decane-soluble portion at 23 ° C of 0.1 to 10%.
%.

Examples of the α-olefin other than ethylene that can be used in the polymerization step (b) include those exemplified in the polymerization step (a).

This polymerization step (b) can be carried out by any of a liquid phase polymerization method such as solution polymerization and suspension polymerization or a gas phase polymerization method. Of these, solution polymerization is particularly preferred.

The polymerization temperature of the olefin using such an olefin polymerization catalyst [II] is usually 0 ° C to 250 ° C, preferably 50 ° C.
In the range of ~ 200 ° C. The polymerization pressure is usually from normal pressure to 100 kg
/ cm ² , preferably normal pressure to 50 kg / cm ² , and the polymerization reaction can be carried out by any of batch, semi-continuous and continuous methods. 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 [II] as described above, the titanium catalyst component [C] is usually converted to Ti atoms per polymerization volume per unit volume.
It is used in an amount of 10 ^{-4 to} 0.5 mmol, preferably about 10 ^{-3 to} 0.1 mmol, and the organoaluminum compound [D] contains 1 to 20 aluminum atoms per 1 mol of titanium atoms.
The organoaluminum oxy compound [E] is used in such an amount that aluminum atoms are usually 4 to 2000 mol, preferably 10 to 500 mol, per 1 mol of titanium atoms. Used in appropriate amounts.

In the present invention, the above two polymerization steps (a) and (b) are performed in any order. That is, after performing the polymerization step (a), the polymerization step (b) may be performed in the presence of the obtained ethylene-based copolymer [I] to form an ethylene-based polymer [II]. After performing step (b), the obtained ethylene-based polymer [II]
The polymerization step (a) may be carried out in the presence of to form an ethylene copolymer [I]. Either way, both steps
Must be done sequentially. In other words, the polymerization step performed at a later stage must be performed in the presence of the polymer formed at the earlier stage. Among them, in the present invention, it is preferable to perform the polymerization step (b) after performing the polymerization step (a).

In the polymerization step (a) and the polymerization step (b), the weight of the ethylene copolymer [I] obtained in the polymerization step (a) is reduced to 10%.
When the amount is 0 parts by weight, the weight of the ethylene-based polymer [II] obtained in the polymerization step (b) is 10 to 1000 parts by weight, preferably 20 to 1000 parts by weight.
Desirably, it is 500 parts by weight.

The intrinsic viscosity [η] of all the polymers (ethylene polymer [I] and ethylene copolymer [II]) is 0.5 to 6 dl / g, preferably 0.7 to 4 dl / g, and the density is 0.87 to 0.94. g / cm ^3, preferably more preferably 0.88~0.93g / cm ³ 0.89~0.92g / cm ³
It is desirable that

Further, a part of the melting curve measured by DSC is 110 ° C. or higher, preferably 115 to 125 ° C., and the relationship between the n-decane soluble part (Ww) and the density (Dw) at 23 ° C. is logWw ≦ −. 50
× Dw + 45.9, preferably logWw ≦ −50 × Dw + 45.8, more preferably logWw ≦ −50 × Dw + 45.7.

In this specification, the density D ₁ of the ethylene polymer [I] or the ethylene copolymer [II] obtained in the first polymerization step (a) is obtained at the time of MFR measurement under a load of 2.16 kg. The obtained strand was heat-treated at 120 ° C. for 1 hour, and gradually cooled to room temperature over 1 hour, and then measured with a density gradient tube.

The intrinsic viscosity [η] of the polymer was measured at 135 ° C. in a decalin solvent. Furthermore, the amount of n-decane soluble part of the above polymer was measured as follows.

About 3 g of the copolymer was precisely weighed and added to 450 ml of n-decane.
After cooling, cool slowly to 23 ° C. Next, the n-decane-insoluble portion was removed by filtration, and n-decane was distilled off from the obtained filtrate to determine the amount of n-decane-soluble portion (% by weight based on the total copolymer).

The copolymer having a small amount of n-decane-soluble portion has excellent blocking resistance.

Further, in the present specification, the density (D ₂ ) intrinsic viscosity [η] ₂ and the amount of n-decane soluble part (W ₂ ) of the polymer obtained in the second polymerization step were calculated as follows. .

In the formula, [η] _W , [η] ₁ , and [η] ₂ are the intrinsic viscosity of the entire polymer, the intrinsic viscosity of the polymer obtained in the first stage, and the intrinsic viscosity of the polymer obtained in the second stage, respectively. F ₁ and f ₂ are the first-stage and second-stage polymerization amount fractions (f ₁ + f ₂ = 1), respectively.

D _W , D ₁ , and D ₂ are the density of the entire polymer, the density of the polymer obtained in the first step, and the density of the polymer obtained in the second step, respectively.

Ww, W1, and W2 are respectively the n-decane soluble part amount of the whole polymer, the n-decane soluble part amount of the polymer obtained in the first stage,
This is the amount of n-decane soluble part of the polymer obtained in the second stage.

The melting point of DSC was used as a measure of the heat resistance of the copolymer.

In the present invention, the olefin polymerization catalyst [I] or [II] may contain other components useful for olefin polymerization in addition to the above components.

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 [C] titanium catalyst component) Under a nitrogen atmosphere, 1 mol of commercially available anhydrous magnesium chloride was suspended in hexane 2, and 6 mol of ethanol was added dropwise with stirring over 1 hour. Reacted for hours. To this, 2.6 mol of diethylaluminum chloride was added dropwise at room temperature, and stirring was continued for 2 hours. Next, after adding 6 mol of titanium tetrachloride, the system was heated to 80 ° C. and reacted while stirring for 3 hours. The solid after the reaction was separated and washed repeatedly with hexane. The solid component thus obtained (T: 3.4wt
% And Mg 21 wt% in terms of titanium atoms, 45.6 mmol of ethanol was added dropwise to 200 ml of a decane suspension containing 5 mmol at room temperature, and then reacted at 90 ° C. for 1 hour. After cooling the system to room temperature, 15 mmol of triethyl aluminum was added,
The reaction was carried out at room temperature for 1 hour to obtain a titanium catalyst component [C].

(Preparation of [B] organoaluminum oxy compound) Al (SO ₄ ) _3.
After charging 37.1 g of 14H ₂ O and 133 ml of toluene, cooling to −5 ° C., trimethylaluminum 4 diluted with 152 ml of toluene was added.
7.9 ml was added dropwise over 1 hour. Then at 0-5 ° C, 1
After reacting for 3 hours, the temperature is raised to 40 ° C over 3 hours,
For a further 72 hours. After the reaction, solid-liquid separation was performed by filtration, and further, toluene was removed with a furnace liquid to obtain a benzene-soluble organoaluminum oxy compound as a white solid.

58.4 ml of the benzene-soluble organoaluminum oxy compound obtained above redissolved in toluene (Al = 2.57 mol /), 90.5 ml of toluene and a Teflon cylinder (1.
25 g (2 mm × 2 mmφ) was charged into a 400 ml flask. After the temperature in the system was cooled to -5 ° C, 1.08 ml of water was gradually added dropwise over 20 minutes. At that time, the temperature in the system was kept at 0 to -5C. After the completion of dropping, the temperature was raised to 80 ° C over 30 minutes.
Allowed to react for hours. Thereafter, the Teflon cylinder was removed with a 32-mesh sieve, so that the solubility in benzene at 60 ° C. was 0.4 wt%, and D ₁₂₆₀ / D measured by IR
A benzene-insoluble organoaluminumoxy compound having a ratio of ₁₂₂₀ of 0.053 was obtained.

(Polymerization) 900 ml of 4-methyl-1-pentene was charged into a 2 stainless steel autoclave sufficiently purged with nitrogen, and the temperature in the system was raised to 75 ° C. Thereafter, polymerization was started by injecting 0.5 mmol of triisobutylaluminum, 0.1 mg of benzene-insoluble organic aluminum oxy compound in terms of aluminum atom, and 0.001 mmol of bis (methylcyclopentadienyl) zirconium dichloride with ethylene. While continuously supplying ethylene, the polymerization was carried out at 80 ° C. for 40 minutes while maintaining the total pressure at 8 kg / cm ² -G [Step (a)]. Then immediately add cyclohexane 80
0 ml, 0.5 Nl of hydrogen and 0.3 mmol of ethylaluminum sesquichloride were charged and heated to 170 ° C. in a separate autoclave from step (a).
l was pumped with ethylene, and then the Ti catalyst component prepared above was converted to titanium atoms, and 0.003 milligram atoms were injected with ethylene to initiate polymerization again. While continuously supplying ethylene, the total pressure was maintained at 25 kg / cm ² -G, and polymerization was carried out at 170 ° C. for 15 minutes (step (b)). The polymerization was stopped by adding a small amount of methanol to the polymerization system, and the obtained polymer solution was precipitated in a large amount of methanol, and then recovered.
Dry overnight at 80 ° C. under reduced pressure. As a result, [η] becomes 1.63
dl / g, the density was 0.905 g / cm ³ , the n-decane soluble part amount was 2.7 wt%, and the melting point peak measured by DSC was
Ethylene 4-methyl-1-appearing at 122, 112, 93 ° C
25.3 g of a pentene copolymer was obtained.

It should be noted that the operation of only the above-mentioned step (a) was carried out to perform the polymer solution
As a result of recovering the polymer in 150 ml, [η] was 1.80 dl / g
The density is 0.891 g / cm ³ and the amount of n-decane soluble part is
9.6 g of an ethylene / 4-methyl-1-pentene copolymer having a melting point of 83 ° C. was obtained at 4.3 wt%. This (a)
According to the result of the step, [η] of the ethylene-4-methyl-1-pentene copolymer obtained in the step (b) was 1.53 dl.
/ g, the density was 0.914 g / cm ³ , the amount of n-decane soluble part was 1.7 wt%, and the polymerization amount was calculated to be 15.7 g.

Comparative Example 1 900 ml of 4-methyl-1-pentene was charged into a 2 stainless steel autoclave sufficiently purged with nitrogen, and the temperature in the system was raised to 90 ° C. Thereafter, 1.0 mmol of triisobutylaluminum, 0.2 mg of benzene-insoluble organoaluminum oxy compound prepared in Example 1 and 0.002 mmol of bis (cyclopentadienyl) zirconium dichloride in terms of aluminum atom are polymerized by injection with ethylene. Started. While continuously supplying ethylene, the total pressure is maintained at 20 kg / cm ² -G,
Polymerization was conducted at 0 ° C. for 40 minutes, and [η] was 1.56 dl / g, the density was 0.907 g / cm ³ , the n-decane soluble part was 0.65 wt%, and the ethylene had a melting point of 97 ° C. -91.0 g of 4-methyl-1-pentene copolymer was obtained.

Comparative Example 2 4-methyl-1-pentene (200 ml) and cyclohexane (8) were placed in a stainless steel autoclave (2) sufficiently purged with nitrogen.
00 ml and 0.5 Nl of hydrogen were charged, and the temperature in the system was raised to 160 ° C. Then, ethyl aluminum sesquichloride
The polymerization was started by injecting 0.35 mmol and 0.013 mg atom of the Ti catalyst component prepared in Example 1 in terms of titanium atom with ethylene. While continuously supplying ethylene, the total pressure was kept at 25 kg / cm ² -G, polymerization was performed at 170 ° C. for 40 minutes, [η] was 1.40 dl / g, the density was 0.908 g / cm ³ , and n
-A decane-soluble part amount of 3.9 wt%, and melting points of 122.7 and 112.
6. 115 g of ethylene / 4-methyl-1-pentene copolymer at 96 ° C. was obtained.

Example 2 The polymerization was performed in the same manner as in Example 1, except that the amount of titanium used in the step (b) was changed to 0.005 mg atom, and [η] was 1.55 dl / g and the density was 0.907 g / cm ³ . , N
A decane-soluble part content of 2.5 wt% and a melting point of 122, 114, 9
36.9 g of an ethylene / 4-methyl-1-pentene copolymer at 4 ° C. was obtained.

[Η] of the ethylene-4-methyl-1-pentene copolymer obtained in the above step (b) is 1.46 dl / g,
The density is 0.913 g / cm ³ and the amount of n-decane soluble part is 1.9 wt.
%, And the polymerization amount was calculated to be 27.3 g.

[Brief description of the drawings]

FIGS. 1 (a) and 1 (b) are illustrations of an olefin polymerization catalyst according to the present invention, and FIG. 2 is a diagram showing a benzene-insoluble aluminum oxy compound.
FIG. 3 shows the IR spectrum of the benzene-soluble aluminum oxy compound.
It is an IR spectrum.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) C08F 4/60-4/70 C08F 10/00-10/02 C08F 210/00-210/16 C08L 23 / 00-23/24

Claims (1)

(57) [Claims] 1. A polymerization step (a) using an olefin polymerization catalyst [I] comprising a transition metal compound [A] containing a ligand having a cycloalkadienyl skeleton and an organoaluminum oxy compound [B]. A step of copolymerizing ethylene and another α-olefin to form an ethylene copolymer [I] having a density of 0.91 g / cm ³ or less and an intrinsic viscosity [η] of 0.5 to 6 dl / g. And a polymerization step (b): an olefin polymerization catalyst comprising a titanium catalyst component [C] containing titanium, magnesium and halogen as essential components, and an organic aluminum compound [D] and / or an organic aluminum oxy compound [E] [ I
Using I], ethylene or ethylene and another α-olefin are polymerized or copolymerized to have a density higher than that of the ethylene copolymer [I] and an intrinsic viscosity of 0.5 to 6 dl.
/ g of the ethylene-based polymer [II], the polymerization step (b) is performed in the presence of the obtained ethylene-based copolymer [I]. ) Or the polymerization step (b), and then the polymerization step (a) in the presence of the obtained ethylene polymer [II]. The density is 0.87 to 0.93 g / cm ³ , and the intrinsic viscosity is such that the ethylene-based polymer [II] is used in a proportion of 10 to 1000 parts by weight with respect to 100 parts by weight of the combined [I]. A method for producing an ethylene-based polymer composition having [η] of 0.5 to 6 dl / g.