JPH06220128A - Production of polyolefin - Google Patents

Abstract

(57) [Summary] [Object] The present invention provides a method for producing a polyolefin that has a wide molecular weight distribution and is excellent in moldability and that can be produced with high polymerization activity. [Structure] The method for producing a polyolefin according to the present invention comprises:
[A] A metallocene compound of a transition metal selected from Group IVB of the periodic table, [B] an organoaluminum oxy compound heat-treated at 50 to 250 ° C., and [C] an organoaluminum compound for olefin polymerization When a polyolefin is produced by polymerizing or copolymerizing an olefin in the presence of a catalyst, the ratio (Al atomic ratio) between the organoaluminum compound and the organoaluminum oxy compound heat-treated at 50 to 250 ° C. is 0.1. ~ 5
In addition, the polymerization is performed in the presence of an aliphatic hydrocarbon medium or an alicyclic hydrocarbon medium.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a polyolefin, and more particularly to a method for producing a polyolefin having a wide molecular weight distribution and excellent moldability with high polymerization activity.

[0002]

TECHNICAL BACKGROUND OF THE INVENTION Ethylene / α-olefin copolymers such as ethylene / propylene copolymers have been
It is widely used after being formed into films, containers, household articles, etc. by various forming methods.

Conventional methods for producing polyolefins such as ethylene / α-olefin copolymers are as follows.
There is known a method of copolymerizing an olefin in the presence of a titanium-based catalyst composed of a titanium compound and an organoaluminum compound or a vanadium-based catalyst composed of a vanadium compound and an organoaluminum compound.

In recent years, as such an olefin polymerization catalyst, a metallocene catalyst comprising a transition metal compound such as zirconocene and an organoaluminumoxy compound has been proposed. If the metallocene catalyst is used, an olefin is polymerized with high activity. It is known that a polyolefin which can be copolymerized and has an excellent composition distribution (narrow composition distribution) can be obtained.

The polyolefin produced using such a highly active metallocene catalyst has a small catalyst residue,
The molded body does not become colored, and hygiene is good. Aromatic hydrocarbons such as toluene are usually used as a polymerization solvent in a method for producing a polyolefin in the presence of a solvent by using the metallocene catalyst by a method such as a solution polymerization method or a suspension polymerization method.

By the way, the polyolefin produced by using the conventional metallocene catalyst as described above has a problem that the molecular weight distribution is narrow and the moldability is poor. Therefore, if a polyolefin production method capable of producing a polyolefin having a wide molecular weight distribution and excellent moldability with a high polymerization activity using a metallocene catalyst appears, its industrial value will be great.

The inventors of the present invention have made earnest studies on a method for producing a polyolefin in view of the above-mentioned prior art. As a result, a metallocene compound, an organoaluminum oxy compound heat-treated at 50 to 250 ° C., and the organoaluminum oxy compound are obtained. Polymerizing an olefin in the presence of an aliphatic hydrocarbon or an alicyclic hydrocarbon using an olefin polymerization catalyst formed of an organoaluminum compound in an amount of 0.1 to 5 in terms of Al atomic ratio with respect to the compound. Further, they have found that a polyolefin having a wide molecular weight distribution and excellent moldability can be produced with high polymerization activity by copolymerization, and thus the present invention has been completed.

[0008]

OBJECT OF THE INVENTION It is an object of the present invention to provide a method for producing a polyolefin capable of producing a polyolefin having a wide molecular weight distribution and excellent moldability with high polymerization activity by using a metallocene olefin polymerization catalyst. .

[0009]

SUMMARY OF THE INVENTION A method for producing a polyolefin according to the present invention comprises: [A] a metallocene compound of a transition metal selected from Group IVB of the periodic table; [B] an organoaluminum oxy compound heat-treated at 50 to 250 ° C .; And [C] in the presence of an olefin polymerization catalyst formed from an organoaluminum compound, in producing a polyolefin by polymerizing or copolymerizing an olefin, the ratio of the above organoaluminum compound to the organoaluminum oxy compound (Al atomic ratio ) Is 0.1 to 5 and the polymerization is carried out in the presence of an aliphatic hydrocarbon medium or an alicyclic hydrocarbon medium.

[0010]

DETAILED DESCRIPTION OF THE INVENTION The method for producing a polyolefin according to the present invention will be specifically described below. The method for producing a polyolefin according to the present invention comprises: [A] a metallocene compound of a transition metal selected from Group IVB of the periodic table, [B] 50
In producing a polyolefin by polymerizing or copolymerizing an olefin in the presence of an organoaluminum oxy compound heat-treated at ˜250 ° C. and an olefin polymerization catalyst formed from the [C] organoaluminum compound, the above organoaluminum is used. The ratio of the compound to the organoaluminum oxy compound (Al atomic ratio) is 0.1 to 5, and the polymerization is carried out in the presence of an aliphatic hydrocarbon medium or an alicyclic hydrocarbon medium.

First, the catalyst used in the present invention will be described. The metallocene compound [A] of a transition metal selected from Group IVB of the periodic table used in the present invention is specifically represented by the following formula [I].

ML _x [I] [wherein M is a transition metal selected from the group consisting of Zr, Ti, Hf, V, Nb, Ta and Cr, and L is a ligand coordinated to the transition metal. And at least one L is a ligand having a cyclopentadienyl skeleton, and L other than the ligand having a cyclopentadienyl skeleton has 1 to 1 carbon atoms.
2 hydrocarbon group, alkoxy group, aryloxy group, trialkylsilyl group, SO ₃ R group (where R is a hydrocarbon group having 1 to 8 carbon atoms which may have a substituent such as halogen), a halogen atom Alternatively, it is a hydrogen atom, and x is the valence of the transition metal. Examples of the ligand having a cyclopentadienyl skeleton include, for example, a cyclopentadienyl group, a methylcyclopentadienyl group, a dimethylcyclopentadienyl group, a trimethylcyclopentadienyl group, and a tetramethylcyclopentadienyl group. , A pentamethylcyclopentadienyl group,
Ethylcyclopentadienyl group, methylethylcyclopentadienyl group, propylcyclopentadienyl group, methylpropylcyclopentadienyl group, butylcyclopentadienyl group, methylbutylcyclopentadienyl group, hexylcyclopentadienyl group Groups such as alkyl-substituted cyclopentadienyl group or indenyl group, 4,5,
Examples thereof include a 6,7-tetrahydroindenyl group and a fluorenyl group. These groups are halogen atoms,
It may be substituted with a trialkylsilyl group or the like.

Of these ligands which coordinate to a transition metal, an alkyl-substituted cyclopentadienyl group is particularly preferable. When the compound represented by the above general formula contains two or more groups having a cyclopentadienyl skeleton, two of them are
Groups having two cyclopentadienyl skeletons are substituted with alkylene groups such as ethylene and propylene, substituted alkylene groups such as isopropylidene and diphenylmethylene, silylene groups or dimethylsilylene groups, diphenylsilylene groups, and methylphenylsilylene groups. It may be bound via a silylene group or the like.

Specific examples of the ligand L other than the ligand having a cyclopentadienyl skeleton include the following. 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. More specifically, the alkyl group includes a methyl group, an ethyl group, a propyl group, and an isopropyl group. Group, butyl group, etc., cycloalkyl group, cyclopentyl group, cyclohexyl group, etc., aryl group, phenyl group, tolyl group, etc., aralkyl group, benzyl group, neophyll group, etc. Are exemplified.

As the alkoxy group, a methoxy group,
Examples thereof include an ethoxy group and a butoxy group, examples of the aryloxy group include a phenoxy group, and examples of the halogen include fluorine, chlorine, bromine, iodine and the like.

Examples of the ligand represented by SO ₃ R include a p-toluenesulfonato group, a methanesulfonato group, and a trifluoromethanesulfonato group. The [A] metallocene compound containing such a ligand having a cyclopentadienyl skeleton is more specifically represented by the following formula [II] when the valence of the transition metal is 4.

R ² _k R ³ _l R ⁴ _m R ⁵ _n M ... [II] (In the formula, M is the above transition metal, and R ² is a group (ligand) having a cyclopentadienyl skeleton. , R ³ , R ⁴ and R ⁵ are groups having a cyclopentadienyl skeleton, alkyl groups, cycloalkyl groups, aryl groups, aralkyl groups, alkoxy groups, aryloxy groups, trialkylsilyl groups, SO ₃ R groups, halogen atoms Or a hydrogen atom, k is an integer of 1 or more, and k + l + m + n = 4.) In the present invention, in the above formula R ² _k R ³ _l R ⁴ _m R ⁵ _n M, R ² ,
A metallocene compound in which at least two of R ³ , R ⁴ and R ⁵ , that is, R ² and R ³ are groups (ligands) having a cyclopentadienyl skeleton is preferably used. Groups having these cyclopentadienyl skeletons include alkylene groups such as ethylene and propylene, substituted alkylene groups such as isopropylidene and diphenylmethylene, silylene groups or dimethylsilylene, diphenylsilylene,
It may be bonded via a substituted silylene group such as a methylphenylsilylene group. R ⁴ and R ⁵ are groups having a cyclopentadienyl skeleton, alkyl groups, cycloalkyl groups, aryl groups, aralkyl groups, alkoxy groups, aryloxy groups, trialkylsilyl groups, SO
₃ R, a halogen atom or a hydrogen atom.

Specific examples of the metallocene compound in which M is zirconium are given below. Bis (indenyl) zirconium dichloride, bis (indenyl) zirconium dibromide, bis (indenyl) zirconium bis (p-toluenesulfonato) bis (4,5,6,7-tetrahydroindenyl) zirconium dichloride, bis (fluorenyl) zirconium Dichloride, ethylenebis (indenyl) zirconium dichloride, ethylenebis (indenyl) zirconium dibromide, ethylenebis (indenyl) dimethylzirconium, ethylenebis (indenyl) diphenylzirconium, ethylenebis (indenyl) methylzirconium monochloride, ethylenebis (indenyl) Zirconium bis (methane sulfonate), ethylene bis (indenyl) zirconium bis (p-toluene sulfonate), ethylene bis (indenyl) zirconium Umbis (trifluoromethanesulfonato), ethylene bis (4,5,6,7-tetrahydroindenyl) zirconium dichloride, isopropylidene (cyclopentadienyl-fluorenyl) zirconium dichloride, isopropylidene (cyclopentadienyl-methylcyclopenta) Dienyl) zirconium dichloride, dimethylsilylenebis (cyclopentadienyl) zirconium dichloride, dimethylsilylenebis (methylcyclopentadienyl) zirconium dichloride, dimethylsilylenebis (dimethylcyclopentadienyl) zirconium dichloride, dimethylsilylenebis (trimethylcyclo) Pentadienyl) zirconium dichloride, dimethylsilylenebis (indenyl) zirconium dichloride, dimethylsilylenebis (2-methylindene) Z) Zirconium dichloride, dimethylsilylenebis (2-methyl, 4-isopropylindenyl) zirconium dichloride, dimethylsilylenebis (2,4,7-trimethylindenyl) zirconium dichloride, dimethylsilylenebis (indenyl) zirconium bis (trifluoromethane) Sulfonato), dimethylsilylene bis (4,5,6,
7-tetrahydroindenyl) zirconium dichloride,
Dimethyl silylene (cyclopentadienyl-fluorenyl) zirconium dichloride, diphenyl silylene bis (indenyl) zirconium dichloride, diphenyl silylene bis (2-methyl, 4-isopropylindenyl) zirconium dichloride, diphenyl silylene bis (2,4,
7-trimethylindenyl) zirconium dichloride, methylphenylsilylene bis (indenyl) zirconium dichloride, bis (cyclopentadienyl) zirconium dichloride, bis (cyclopentadienyl) zirconium dibromide, bis (cyclopentadienyl) methylzirconium monochloride Chloride, bis (cyclopentadienyl) ethyl zirconium monochloride, bis (cyclopentadienyl) cyclohexyl zirconium monochloride, bis (cyclopentadienyl) phenyl zirconium monochloride, bis (cyclopentadienyl) benzyl zirconium monochloride, Bis (cyclopentadienyl) zirconium monochloride monohydride, bis (cyclopentadienyl) methylzirconium monohydride, bis Cyclopentadienyl) dimethylzirconium, bis (cyclopentadienyl) diphenylzirconium, bis (cyclopentadienyl) dibenzylzirconium, bis (cyclopentadienyl) zirconium methoxychloride, bis (cyclopentadienyl) zirconium ethoxy chloride , Bis (cyclopentadienyl) zirconium bis (methanesulfonate),
Bis (cyclopentadienyl) zirconium bis (p-toluenesulfonato), bis (cyclopentadienyl) zirconium bis (trifluoromethanesulfonato), bis (methylcyclopentadienyl) zirconium dichloride, bis (ethylcyclopentadiene) (Enyl) zirconium dichloride, bis (dimethylcyclopentadienyl)
Zirconium dichloride, bis (dimethylcyclopentadienyl) zirconium ethoxy chloride, bis (dimethylcyclopentadienyl) zirconium bis (trifluoromethanesulfonato), bis (ethylcyclopentadienyl) zirconium dichloride, bis (methylethylcyclopentadiene) (Enyl) zirconium dichloride, bis (propylcyclopentadienyl) zirconium dichloride, bis (methylpropylcyclopentadienyl)
Zirconium dichloride, bis (butylcyclopentadienyl) zirconium dichloride, bis (methylbutylcyclopentadienyl) zirconium dichloride, bis (methylbutylcyclopentadienyl) zirconium bis (methanesulfonato), bis (trimethylcyclopentadienyl) ) Zirconium dichloride, bis (triethylcyclopentadienyl) zirconium dichloride, bis (tetramethylcyclopentadienyl) zirconium dichloride, bis (pentamethylcyclopentadienyl) zirconium dichloride, bis (hexylcyclopentadienyl) zirconium dichloride, Bis (trimethylsilylcyclopentadienyl) zirconium dichloride, bis (diethylcyclopentadienyl) zirconium dichloride, bi (Dimethylethylcyclopentadienyl) zirconium dichloride, bis (dimethylcyclopentadienyl) zirconium dibromide, bis (dimethylcyclopentadienyl) zirconium methoxy chloride, bis (dimethylcyclopentadienyl) zirconium ethoxy chloride, bis (dimethyl Cyclopentadienyl) zirconium butoxycyclolide, bis (dimethylcyclopentadienyl) zirconium diethoxide, bis (dimethylcyclopentadienyl) zirconium methyl chloride, bis (dimethylcyclopentadienyl) zirconium dimethyl, bis (dimethylcyclopenta) Dienyl) zirconium benzyl chloride, bis (dimethylcyclopentadienyl) zirconium dibenzyl, bis (dimethylcyclopentadienyl) Zirconium phenyl chloride, bis (dimethyl cyclopentadienyl) zirconium hydride chloride.

In the above examples, the di-substituted cyclopentadienyl ring includes 1,2- and 1,3-substituted compounds, and the tri-substituted compound is 1,2,3- and 1,2,4-substituted compounds. Including the body. Alkyl groups such as propyl and butyl are n-, i-, sec-, tert-
Including isomers such as.

In the zirconium compound as described above, a compound in which zirconium is replaced with titanium, hafnium, vanadium, niobium, tantalum or chromium can be used.

In the present invention, the metallocene compound [A] is preferably a zirconocene compound having a central metal atom of zirconium and having two substituted cyclopentadienyl groups as ligands. Among such zirconocene compounds, those having a methyl group or an ethyl group as a substituent and having a substituted cyclopentadienyl group having 2 to 3 substituents as a ligand are preferable. Specific examples of such a preferable zirconocene compound include bis (dimethylcyclopentadienyl) zirconium dichloride, bis (diethylcyclopentadienyl) zirconium dichloride, bis (methylethylcyclopentadienyl) zirconium dichloride, and bis (methyl). Ethylcyclopentadienyl) zirconium dichloride, bis (dimethylethylcyclopentadienyl) zirconium dichloride, bis (dimethylcyclopentadienyl) zirconium dibromide, bis (dimethylcyclopentadienyl) zirconium methoxychloride, bis (dimethylcyclopenta) Dienyl) zirconium ethoxy chloride, bis (dimethylcyclopentadienyl) zirconium butoxycyclolide, bis (dimethylcyclopentadienyl) di Conium diethoxide, bis (dimethylcyclopentadienyl) zirconium methyl chloride, bis (dimethylcyclopentadienyl) zirconium dimethyl, bis (dimethylcyclopentadienyl) zirconium benzyl chloride, bis (dimethylcyclopentadienyl) zirconium Dibenzyl, bis (dimethylcyclopentadienyl) zirconium phenyl chloride, bis (dimethylcyclopentadienyl) zirconium hydride chloride bis (trimethylcyclopentadienyl) zirconium dicyclolide, bis (triethylcyclopentadienyl) zirconium dicyclolide, Is mentioned. Among these,
Particularly preferred is zirconocene having a 1,3-substituted cyclopentadienyl group as a ligand, and specific examples include bis (1,3-dimethylcyclopentadienyl) zirconium dichloride and bis (1,3- Diethylcyclopentadienyl)
Examples thereof include zirconium dichloride and bis (1-methyl-3-ethylcyclopentadienyl) zirconium dichloride.

These compounds may be used alone,
You may use it in combination of 2 or more type. It may be diluted with a hydrocarbon or a halogenated hydrocarbon before use. In the present invention, the metallocene compound [A] is preferably used by diluting it with a hydrocarbon, particularly an aliphatic hydrocarbon or an alicyclic hydrocarbon as described below.

Further, the above metallocene compound [A]
May be supported on a particulate carrier for use. Examples of such carriers include SiO ₂ , Al ₂ O ₃ , B ₂ O ₃ , MgO,
ZrO ₂ , CaO, TiO ₂ , ZnO, Zn ₂ O, SnO ₂ ,
Inorganic carriers such as BaO and ThO, and resins such as polyethylene, polypropylene, poly-1-butene, poly-4-methyl-1-pentene, and styrene-divinylbenzene copolymer can be used. These can also be used in combination of two or more kinds.

Next, the heat-treated organoaluminum oxy compound [B] used in the present invention will be described.
[B] The heat-treated organoaluminum oxy compound used in the present invention contains an organoaluminum oxy compound as described below at 50 to 250 ° C., preferably 80 to 220 ° C.
C. More preferably, it is prepared by heat treatment at 90 to 200.degree. Although the heat treatment time varies greatly depending on the heating temperature, it is generally 0.2 to 20 hours, preferably 0.5 to 50 hours.

For the heat treatment of the organoaluminum oxy compound, for example, (i) the organoaluminum oxy compound is dissolved or dispersed in a hydrocarbon solvent, and the resulting solution or dispersion is heated to the above temperature preferably with stirring. Alternatively, or (ii) the organoaluminum oxy compound is heated as it is.

Of these, the method (i) is preferable. When the organic aluminum oxy compound is heat-treated in a hydrocarbon solvent, specific examples of the hydrocarbon solvent include aromatic hydrocarbons such as benzene, toluene, xylene, cumene and cymene, pentane, hexane, heptane and octane. , Aliphatic hydrocarbons such as decane, dodecane, hexadecane and octadecane, alicyclic hydrocarbons such as cyclopentane, cyclohexane, cyclooctane and methylcyclopentane, petroleum fractions such as gasoline, kerosene and gas oil, or their halides Among them are hydrocarbon solvents such as chloride and bromide.

Of these, aromatic hydrocarbons are preferable, and toluene is particularly preferable. At this time, the concentration of the organoaluminum oxy compound in the hydrocarbon solvent is usually 0.01 to 5 gram atom / liter, preferably 0.05 to 3 gram atom / liter, in terms of aluminum atom.

The heat treatment of such an organoaluminum oxy compound is particularly preferably carried out as described above, but other catalyst components such as the metallocene compound [A].
It can also be carried out in the presence of an organoaluminum compound [C].

Next, the organoaluminum oxy compound to which the heat treatment is applied in the present invention will be explained. The organoaluminum oxy compound may be a conventionally known aluminoxane, and is described in JP-A-2-78687. It may be a benzene-insoluble organoaluminum oxy compound as described above.

Such conventionally known aluminoxane can be produced, for example, by the following method. (1) Compounds containing adsorbed water or salts containing water of crystallization, such as magnesium chloride hydrate, copper sulfate hydrate, aluminum sulfate hydrate, nickel sulfate hydrate, ceric chloride hydrate, etc. In a hydrocarbon medium in which
A method in which an organoaluminum compound such as trialkylaluminum is added and reacted to recover a hydrocarbon solution.

(2) A method in which water (water, ice or steam) is directly applied to an organoaluminum compound such as trialkylaluminum in a medium such as benzene, toluene, ethyl ether or tetrahydrofuran to recover it as a solution of the above medium. .

(3) A method of reacting an organoaluminum compound such as trialkylaluminum with an organotin oxide such as dimethyltin oxide or dibutyltin oxide in a medium such as decane, benzene or toluene.

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

Specific examples of the organoaluminum compound used for producing the aluminoxane solution include trimethylaluminum, triethylaluminum, tripropylaluminum, triisopropylaluminum, tri-n-butylaluminum, triisobutylaluminum, Tri sec-butyl aluminum, tri tert
-Butyl aluminum, tripentyl aluminum, trihexyl aluminum, trioctyl aluminum,
Trialkyl aluminums such as tridecyl aluminum, tricyclohexyl aluminum and tricyclooctyl aluminum, dimethyl aluminum chloride, diethyl aluminum chloride, diethyl aluminum bromide, dialkyl aluminum halides such as diisobutyl aluminum chloride, diethyl aluminum hydride, dialkyl aluminum such as diisobutyl aluminum hydride. Examples thereof include dialkyl aluminum alkoxides such as hydride, dimethyl aluminum methoxide and diethyl aluminum ethoxide, and dialkyl aluminum aryloxides such as diethyl aluminum phenoxide.

Of these, trialkylaluminum is particularly preferable. As an organoaluminum compound,
Isoprenylaluminum represented by the following general formula can also be used.

(I-C ₄ H ₉ ) _x Al _y (C ₅ H ₁₀ ) _z (wherein x, y and z are positive numbers, and z ≧ 2x) The above-mentioned organic aluminum The compounds may be used alone or in combination.

Specific examples of the solvent used for producing the aluminoxane solution include aromatic hydrocarbons such as benzene, toluene, xylene, cumene and cymene,
Aliphatic hydrocarbons such as pentane, hexane, heptane, octane, decane, dodecane, hexadecane and octadecane, alicyclic hydrocarbons such as cyclopentane, cyclohexane, cyclooctane and methylcyclopentane, petroleum fractions such as gasoline, kerosene and gas oil Or hydrocarbon solvents such as halides, especially chlorides and bromides.

Further, ethers such as ethyl ether and tetrahydrofuran can be used. Of these, aromatic hydrocarbons are preferable, and toluene is particularly preferable.

The benzene-insoluble organoaluminum oxy compound to be heat-treated according to the present invention is analyzed by infrared spectroscopy (IR) for the benzene-insoluble organoaluminum oxy compound, and the absorbance at around 1220 cm ^-1 ( and D _1220), the absorbance at around 1260 cm ^-1 is (D ₁₂₆₀₎ and the ratio of (D ₁₂₆₀ / D _1220), particularly preferably preferably 0.09 or less 0.08 or less 0.04 to 0.
It is desirable that it is 07.

Such a benzene-insoluble organoaluminum oxy compound is presumed to have an alkyloxy aluminum unit (i) represented by the following formula.

[0041]

[Chemical 1]

An alkyloxy aluminum unit represented by the formula: wherein R ⁷ is a hydrocarbon group having 1 to 12 carbon atoms.
presumed to have (i). In the above alkyloxyaluminum unit (i), R ⁷ 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. , Decyl group, cyclohexyl group, cyclooctyl group and the like. Of these, a methyl group and an ethyl group are preferable, and a methyl group is particularly preferable.

The benzene-insoluble organoaluminum oxy compound may contain an oxyaluminum unit (ii) represented by the following formula in addition to the alkyloxyaluminum unit (i) as described above.

[0044]

[Chemical 2]

[In the formula, R ⁸ is a hydrocarbon group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or 6 to 20 carbon atoms.
Is an aryloxy group, a hydroxyl group, a halogen or hydrogen, and R ⁷ and R ⁸ of the unit (i) are different from each other.] When the benzene-insoluble organoaluminum oxy compound contains an oxyaluminum unit (ii) The above-mentioned alkyloxyaluminum unit (i) is 30 mol% or more, preferably 50 mol% or more, particularly preferably 7
It is preferably contained in an amount of 0 mol% or more.

A method for producing the above-mentioned benzene-insoluble organoaluminum oxy compound is described, for example, in JP-A-2-
It is described in Japanese Patent No. 78687, Japanese Patent Application Laid-Open No. 3-203910, and the like.

[B] 50 to 25 used in the present invention
The organoaluminum oxy compound heat-treated at 0 ° C. (hereinafter, may be simply referred to as [B] heat-treated organoaluminum oxy compound) may contain a small amount of a metal component other than aluminum. [B] The heat-treated organoaluminum oxy compound can also be used by supporting it on the carrier as described above.

In the present invention, the above [B] heat-treated organoaluminum oxy compound is polymerized as a slurry of an aliphatic hydrocarbon or an alicyclic hydrocarbon used as a polymerization medium in the present invention as described below. It may be supplied to the system. This aliphatic hydrocarbon or alicyclic hydrocarbon is
It is preferably the same as the polymerization medium.

The slurry of the [B] heat-treated organoaluminum oxy compound is appropriately prepared by dispersing the [B] heat-treated organoaluminum oxy compound in an aliphatic hydrocarbon or an alicyclic hydrocarbon. When the prepared [A] heat-treated organoaluminum oxy compound is a toluene solution, it is prepared specifically as follows, for example. (1) [B] A toluene solution of the heat-treated organoaluminum oxy compound was distilled off, and the obtained powdery [B] heat-treated organoaluminum oxy compound was mechanically pulverized to obtain an aliphatic compound. A method of suspending in a hydrocarbon or alicyclic hydrocarbon. (2) [B] Toluene was distilled off from the toluene solution of the heat-treated organoaluminum oxy compound, and the obtained powdery [B] heat-treated organoaluminum oxy compound was added to an aliphatic hydrocarbon or alicyclic carbon. After adding hydrogen
[B] A method of mechanically pulverizing a heat-treated organoaluminum oxy compound. (3) [B] A toluene solution of the heat-treated organoaluminum oxy compound is brought into contact with an aliphatic hydrocarbon or an alicyclic hydrocarbon to precipitate the [B] heat-treated organoaluminum oxy compound, How to exchange media.

In the above description, the case where the toluene solution of the organoaluminum oxy compound [B] is used is explained. However, the heat treatment of the toluene solution of the organoaluminum oxy compound [B] is performed in place of the [B] heat treatment. It is also possible to use a benzene solution of an organic aluminum oxy compound.

[B] used in the above contact
The concentration of the heat-treated toluene solution of the organoaluminum oxy compound is usually 0.
1-10 gram atom / liter, preferably 0.5-7
Gram atom / liter, more preferably 0.5 to 5 gram atom / liter.

In the contact as described above, the aliphatic hydrocarbon or the alicyclic hydrocarbon has a volume ratio of 0. to the toluene solution of the heat-treated organoaluminum oxy compound [B]. 3 to 10, preferably 0.5 to
Used in an amount of 5.

When the [B] heat-treated organoaluminum oxy compound is supplied to the polymerization vessel as a slurry of an aliphatic hydrocarbon or an alicyclic hydrocarbon, the step of drying the polyolefin obtained by the polymerization is simplified. It is possible to produce a polyolefin having no odor of a polymerization medium such as an odor of toluene.

Examples of the organoaluminum compound [C] used in the present invention include organoaluminum compounds represented by the following formula [VI]. During ^{_{R 9 n AlX 3-n ...}} [VI] formula, R ⁹ is a hydrocarbon group having 1 to 12 carbon atoms, X is a halogen atom or a hydrogen atom, n represents 1 to 3.

Examples of such a hydrocarbon group having 1 to 12 carbon atoms include an alkyl group, a cycloalkyl group and an aryl group. Specifically, a methyl group, an ethyl group, an n-propyl group, Examples thereof include isopropyl group, isobutyl group, pentyl group, hexyl group, octyl group, cyclopentyl group, cyclohexyl group, phenyl group and tolyl group.

Such an organoaluminum compound [C]
Specifically, the following compounds are used. Trialkyl aluminum such as trimethyl aluminum, triethyl aluminum, triisopropyl aluminum, triisobutyl aluminum, trioctyl aluminum, tri-2-ethylhexyl aluminum, alkenyl aluminum such as isoprenyl aluminum, dimethyl aluminum chloride, diethyl aluminum chloride, diisopropyl aluminum chloride, diisobutyl. Dialkyl aluminum halides such as aluminum chloride and dimethyl aluminum bromide, methyl aluminum sesquichloride, ethyl aluminum sesquichloride, isopropyl aluminum sesquichloride, butyl aluminum sesquichloride, alkyl aluminum sesquihalides such as ethyl aluminum sesquibromide, methyl Aluminum dichloride,
Alkyl aluminum dihalides such as ethyl aluminum dichloride, isopropyl aluminum dichloride and ethyl aluminum dibromide, alkyl aluminum hydrides such as diethyl aluminum hydride and diisobutyl aluminum hydride.

As the organoaluminum compound [C], a compound represented by the following formula [VII] can also be used. During ^{_{R 9 n AlY 3-n ...}} [VII] formula, R ⁹ is the same as the formula [VI], Y is -OR ¹⁰
Group, -OSiR ¹¹ ₃ group, -OAlR ¹² ₂ group, -NR
¹³ ₂ group, —SiR ¹⁴ ₃ group or —N (R ¹⁵ ) AlR ¹⁶ ₂ group. R ¹⁰ , R ¹¹ , R ¹² and R ¹⁶ are a methyl group, an ethyl group, an isopropyl group, an isobutyl group, a cyclohexyl group, a phenyl group and the like, and R ¹³ is hydrogen, a methyl group, an ethyl group, an isopropyl group, a phenyl group, A trimethylsilyl group and the like, and R ¹⁴ and R ¹⁵ are a methyl group, an ethyl group and the like. n is 1-2.

As such an organoaluminum compound, the following compounds are specifically used. (i) compounds represented by R ⁹ _n Al (OR ¹⁰ ) _3-n , such as dimethyl aluminum methoxide, diethyl aluminum ethoxide, diisobutyl aluminum methoxide, and (ii) R ⁹ _n Al (OSi R ¹¹ ₃ ) A compound represented by _3-n , for example, Et ₂ Al (OSi Me ₃ ) (iso-Bu) ₂ Al (OSi Me ₃ ) (iso-Bu) ₂ Al (OSi Et ₃ ), (iii) R ⁹ _n A
a compound represented by l (OAlR ¹² ₂ ) _3-n , for example,
Et ₂ AlOAlEt ₂ (iso-Bu) ₂ AlOAl (iso-Bu) _2, etc., (iv) R ⁹ _n A
a compound represented by l (NR ¹³ ₂ ) _3-n , such as Me ₂
AlNEt ₂ Et ₂ AlNHMe Me ₂ AlNHET Et ₂ AlN (Si Me ₃ ) ₂ (iso-Bu) ₂ AlN (SiMe ₃ ) ₂ etc., (v) R ⁹ _n Al
A compound represented by (Si R ¹⁴ ₃ ) _3-n , for example, (is
o-Bu) ₂ AlSi Me _3, etc., (vi) R ⁹ _n Al (N
A compound represented by (R ¹⁵ ) AlR ¹⁶ ₂ ) _3-n , for example, Et ₂ AlN (Me) AlEt ₂ , (iso-Bu) ₂ AlN (E
t) Al (iso-Bu) _{2 and the} like.

In the present invention, among the above-mentioned organoaluminum compounds [C], trialkylaluminum is preferable, and triisobutylaluminum is particularly preferable.
Two or more kinds of these organoaluminum compounds [C] can be mixed and used.

In the present invention, an olefin is formed in the presence of an olefin polymerization catalyst formed from the above [A] metallocene compound, [B] heat-treated organoaluminum oxy compound and [C] organoaluminum compound. Are polymerized or copolymerized.

The olefin polymerized in the present invention includes:
Examples include α-olefins having 2 to 20 carbon atoms and, if necessary, non-conjugated dienes. Specific examples of the α-olefin having 2 to 20 carbon atoms include ethylene, propylene, 1-butene, 1-pentene, 1-hexene and 4-methyl-1.
-Pentene, 1-octene, 1-decene, 1-dodecene and the like.

The non-conjugated diene is 5-ethylidene
Cyclic non-conjugated dienes such as -2-norbornene, 5-propylidene-5-norbornene, dicyclopentadiene, 5-vinyl-2-norbornene, 1,4-hexadiene, 4-methyl-1,4
-Hexadiene, 5-methyl-1,4-hexadiene, 5-methyl
Examples include chain-like non-conjugated dienes such as -1,5-heptadiene, 6-methyl-1,5-heptadiene, 6-methyl-1,7-octadiene, 7-methyl-1,6-octadiene.

In the present invention, an aliphatic hydrocarbon or an alicyclic hydrocarbon is used as a medium when carrying out the polymerization.
The aliphatic hydrocarbon or alicyclic hydrocarbon used in the present invention preferably has a boiling point of 100 ° C. or lower, more preferably 90 ° C. or lower, particularly preferably 75 ° C. or lower.

Specific examples of such an aliphatic hydrocarbon or alicyclic hydrocarbon include 2,2-dimethylpropane and 2-
Methylbutane, 2,2-dimethylbutane, 2,3-dimethylbutane, 2,2,3-trimethylbutane, n-pentane, 2-methylpentane, 3-methylpentane, 2,2-dimethylpentane, 3,
3-dimethylpentane, 2,3-dimethylpentane, 2,4-dimethylpentane, n-hexane, 2-methylhexane, 3-methylhexane, n-heptane, cyclohexane, methylcyclopentane, dimethylcyclopentane, etc. . These may be mixed and used.

Two or more kinds of these aliphatic hydrocarbons or alicyclic hydrocarbons may be used in combination. Of these, hexane, methylpentane, methylcyclopentane and mixtures thereof are preferably used.

In the polymerization, the metallocene compound [A] is usually converted into a transition metal atom in an amount of about 0.00005 to 0.1 mmol, preferably about 0.0001 to 0.05 mmol, per liter of the polymerization volume. Amount of [B]
The heat-treated organoaluminum oxy compound is
The aluminum atom in the [B] heat-treated organoaluminum oxy compound is usually about 1 to 10000 mol, preferably 10 to 5000 mol, relative to 1 mol of the transition metal atom of the [A] metallocene compound. Used in quantity.

In the present invention, the ratio ([C] / [B] ratio, Al atomic ratio) of the [C] organoaluminum compound to the [B] heat-treated organoaluminum oxy compound is 0.
It is used in an amount of 1 to 5, preferably 0.3 to 3.0, particularly preferably 0.5 to 2.0.

The polymerization temperature is usually from -20 ° C to 200 ° C.
° C, preferably 0 ° C to 150 ° C, particularly preferably 20
℃ ~ 120 ℃, the polymerization pressure is usually atmospheric pressure ~ 10
It is desirable that the pressure is 0 kg / cm ² , preferably atmospheric pressure to 50 kg / cm ² , and particularly preferably atmospheric pressure to 30 kg / cm ² .

The molecular weight can be adjusted by changing the polymerization conditions such as the polymerization temperature, or can be adjusted by controlling the amount of hydrogen (molecular weight modifier) used.

The above-mentioned polymerization can be carried out by a solution polymerization method, a suspension polymerization method or the like. Of these, the solution polymerization method is preferred in the invention. Also, the polymerization is batch type,
It can be carried out by either a semi-continuous method or a continuous method, but it is preferably carried out continuously. Further, the polymerization can be carried out in two or more stages by changing the reaction conditions.

The polymer produced immediately after the polymerization can be recovered by a conventionally known separation / recovery method. In the case of solution polymerization, the solvent is evaporated directly to dryness, or after phase separation,
A method of evaporating the solvent of the concentrated phase and drying to dryness is preferable.

Using the olefin polymerization catalyst as described above, in the presence of an aliphatic hydrocarbon or an alicyclic hydrocarbon,
By polymerizing or copolymerizing an olefin, a polyolefin having a wide molecular weight distribution and excellent moldability can be produced with high activity.

The polyolefin obtained in the present invention is the above-mentioned α-olefin homopolymer or α-olefin copolymer, and further a copolymer of α-olefin and, if necessary, non-conjugated diene.

The polyolefin obtained in the present invention is preferably a copolymer of ethylene, an α-olefin and, if necessary, a non-conjugated diene, and the constitutional unit derived from ethylene is 30 to 95 mol. %, More preferably from 40 to 93 mol%, from 5 to 70 mol%, preferably from 7 to 60 mol%, of the constituent units derived from an α-olefin having 3 or more carbon atoms, from the non-conjugated diene. Particularly preferred are low crystalline polyolefins which contain derived structural units in an amount of 0 to 10 mol%.

The polyolefin obtained by the present invention is 13
The intrinsic viscosity [η] measured in decahydronaphthalene at 5 ° C is usually 0.01 to 20 dl / g, preferably 0.
1-10 dl / g, more preferably 0.5-5.0 dl / g
It is g.

The polyolefin obtained in the present invention has a molecular weight distribution (Mw / Mn) of 2.5 to 7 determined by gel permeation chromatography (GPC).
It is preferably 2.7 to 6, particularly preferably 3 to 5.

The above molecular weight distribution (Mw / M
n) is determined according to Takeuchi (Maruzen) “Gel Permeation Chromatography”. The polyolefin obtained by using the olefin polymerization catalyst as described above in the present invention is excellent in the composition distribution of each component.

Further, according to the present invention, since the aliphatic hydrocarbon or alicyclic hydrocarbon which does not have a bad odor and is easily volatilized is used as the polymerization medium, the drying step can be simplified and finally A polymer in which the odor of the polymerization medium does not remain can be easily obtained.

[0079]

According to the present invention, a polyolefin having a wide molecular weight distribution and excellent moldability can be produced with high polymerization activity.

The polyolefin obtained by the present invention is
It has excellent moldability, less catalyst residue, does not color the molded product, has good hygiene, and has no odor of polymerization solvent such as toluene odor, and is suitable for food container materials. be able to.

[0081]

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

In the following examples, the intrinsic viscosity [η] was measured at 135 ° C. in decahydronaphthalene, and the polymer composition was ¹³ C-NMR, molecular weight distribution (Mw / Mn).
Was measured by GPC.

[0083]

Example 1 <Heat Treatment of Methylalumoxane (MAO)> Heat treatment was performed using a 1 liter glass reactor equipped with a stirring blade.

500 ml of a toluene solution of methylaluminoxane (MAO) (1.64 mg atom / ml in terms of aluminum atom) was inserted and the mixture was heated at 95 ° C. for 15 hours.
Heating was continued with stirring.

<Pressure Batch Copolymerization of Ethylene and Propylene> Copolymerization of ethylene and propylene was carried out using a 2 liter autoclave equipped with a stirring blade.

0.9 liters of hexane dehydrated and purified from the upper portion of the polymerization vessel, 38 liters of propylene in a gas, and methylaluminoxane (M) heat-treated as described above.
AO) solution 0.18 ml, triisobutylaluminum (TIBA) hexane solution (1 mmol / ml) was added to 0.10 ml.
22 ml was inserted. After heating the system to 70 ℃, the total pressure is 7kg.
Ethylene was inserted so that it would be / cm ² · G.

Then, using a pressure equalizing tube, 0.25 ml of a hexane solution of bis (1,3-dimethylcyclopentadienyl) zirconium dichloride (0.002 mmol / ml) was inserted, and the temperature was 80 ° C. and the total pressure was 8 kg. Polymerization was carried out for 20 minutes while maintaining / cm ² · G. After depressurization, the polymer solution was taken out and dried.

The yield was 36.4 g. The obtained copolymer has a constitutional unit derived from ethylene of 83 mol%.
And the intrinsic viscosity [η] is 1.9 dl / g, and Mw /
Mn was 3.9.

The results are shown in Table 1.

[0090]

Examples 2 and 3 A copolymerization reaction was carried out in the same manner as in Example 1 except that the amount of triisobutylaluminum was changed as shown in Table 1.

The results are shown in Table 1.

[0092]

Comparative Example 1 A copolymerization reaction was carried out in the same manner as in Example 1 except that toluene was used as the polymerization solvent.

The results are shown in Table 1.

[0094]

Comparative Example 2 A copolymerization reaction was carried out in the same manner as in Example 1 except that the amount of triisobutylaluminum and the polymerization time were changed as shown in Table 1.

The results are shown in Table 1.

[0096]

Comparative Example 3 A copolymerization reaction was carried out in the same manner as in Example 1 except that triisobutylaluminum was not used and the polymerization time was changed as shown in Table 1.

The results are shown in Table 1.

[0098]

[Table 1]

In Table 1, TIBA: triisobutylaluminum Al ratio: TIBA / MAO (molar ratio)

[0100]

Example 4 <Preparation of Hexane Slurry of Heat-treated Methylaluminoxane> In a nitrogen atmosphere, a SUS reactor equipped with a stirring blade was charged with 1.5 g atom / liter of aluminum aluminoxane (MAO) as an aluminum atom. 10 liters of a toluene solution was supplied, and heat treatment was performed at 95 ° C. for 2 hours while stirring. Then, the temperature was lowered to room temperature, and 10 liters of nitrogen-substituted hexane was added dropwise over 1 hour. The solid methylaluminoxane thus produced was filtered, washed with hexane, and a part thereof was taken out for analysis and dried under reduced pressure, and suspended in hexane to prepare a hexane slurry of methylaluminoxane.

<Ethylene / Propylene Copolymerization> Tests were carried out by the continuous polymerization apparatus shown in FIG. To a continuous polymerization reactor A having a volume of 300 liters, dehydrated and purified hexane was supplied from a tube 1 at a rate of 34.7 liters / hr, and a hexane solution of triisobutylaluminum (TIBA) was supplied from a tube 2 (2.5 mmol / liter). ) 2.5 liters /
Methylaluminoxane (MAO) hexane slurry (4.8 mg atom / liter as aluminum atom) at a rate of 1.3 liters / hr of bis (1,3-dimethylcyclopentadienyl) zirconium dichloride Of hexane (0.042 mmol / liter) was continuously fed at a rate of 1.5 liter / hr (total hexane 40 liter / hr). At the same time, ethylene was fed continuously at a rate of 4.2 kg / hr, propylene was fed at a rate of 4.9 kg / hr, and hydrogen was continuously fed at a rate of 1.3 liter / hr from the tubes 3 and 4, respectively, at a polymerization temperature of 80 ° C. Total pressure 7.7kg
Polymerization was carried out under the conditions of / cm ² · G and residence time of 2 hours.

The ethylene / propylene copolymer solution produced in the polymerization reactor A was continuously discharged through the pipe 5 at a flow rate of 53 liter / hr, introduced into the heat exchanger B, and further into the hopper C. Then, the solvent was evaporated and separated here to obtain an ethylene / propylene copolymer at a rate of 5.0 kg / hr.

The ethylene / propylene copolymer obtained had an intrinsic viscosity [η] of 1.31 dl / g, a constitutional unit derived from ethylene of 82.6 mol%, and an Mw of
/ Mn was 4.5.

[Brief description of drawings]

FIG. 1 shows a continuous polymerization apparatus used in Examples.

Claims (2)

[Claims] 1. Formed from [A] a metallocene compound of a transition metal selected from Group IVB of the periodic table, [B] an organoaluminumoxy compound heat-treated at 50 to 250 ° C., and [C] an organoaluminum compound. When an olefin is polymerized or copolymerized in the presence of an olefin polymerization catalyst to produce a polyolefin, the ratio (Al atomic ratio) between the organoaluminum compound and the organoaluminum oxy compound heat-treated at 50 to 250 ° C. Is 0.1 to 5, and the polymerization is carried out in the presence of an aliphatic hydrocarbon medium or an alicyclic hydrocarbon medium. 2. The method for producing a polyolefin according to claim 1, wherein the organoaluminum compound is triisobutylaluminum.