JP3486038B2 - Method for producing dry prepolymerized catalyst for olefin polymerization - Google Patents

Description

Detailed Description of the Invention

[0001]

The present invention relates are those which relate to polymerization activity and production <br/> how excellent olefin polymerization dried prepolymerized catalyst flowability.

[0002]

BACKGROUND OF THE INVENTION Polyolefins, or olefin polymers represented by linear low-density polyethylene (LLDPE), which is a copolymer of ethylene and α-olefin, are widely used as film forming materials. ing. The olefin polymer is conventionally produced by (co) polymerizing an olefin in the presence of a titanium-based solid catalyst component containing magnesium, titanium and halogen as essential components. Further, in recent years, as a catalyst capable of (co) polymerizing olefins with higher polymerization activity,
A metallocene catalyst comprising a solid catalyst component containing a metallocene compound of Group IVB metal of the periodic table such as zirconium and an organoaluminum component has been developed.

The (co) polymerization of olefin using the above catalyst is carried out by a solution polymerization method, a suspension polymerization method or a gas phase polymerization method. The gas phase polymerization method allows the polymer to be obtained in the form of particles, and the liquid phase polymerization method does not require the polymer precipitation step and the polymer separation step after the polymerization, which are more important than the liquid phase polymerization method. The manufacturing process can be simplified and the manufacturing cost can be reduced.

In the gas phase polymerization method, a solid catalyst and an olefin are continuously supplied to a polymerization reactor (fluidized bed reactor) to polymerize or copolymerize the olefin in a fluidized bed, and the obtained particulate polymer is obtained. Is continuously extracted to continuously perform (co) polymerization of olefin. However, when olefins are polymerized by the gas phase polymerization method, polymer particles adhere to each other in the fluidized bed to form polymer lumps, which lowers the fluidity of the fluidized bed. In some cases, the polymer was adhered to the sheet to form a sheet-like polymer, and the fluidity of the fluidized bed was lowered, and the operation had to be stopped.

Under these circumstances, it has been desired to develop a polymerization method capable of stably carrying out gas phase polymerization of olefins for a long period of time. In particular, metallocene-based catalysts having excellent polymerization activity are used to produce olefins for a long period of time. The advent of a polymerization method that allows stable gas phase polymerization is desired.

As a result of intensive studies on the problems in such a gas phase polymerization method of olefins, the present inventors introduced the solid catalyst into the polymerization system in order to supply it as a slurry of a hydrocarbon medium to the polymerization reactor. It was found that one of the causes is that hydrocarbons are liquefied depending on the temperature and deteriorate the fluidity of the fluidized bed. However, if it is attempted to feed the solid catalyst to the polymerization reactor without making it into a slurry,
Since the solid catalyst has low fluidity, it is difficult to stably supply it to the polymerization reactor, or the addition of a fluidity improver to improve the fluidity of the solid catalyst may lower the polymerization activity. there were. Further, when the solid catalyst is dried in order to improve the fluidity of the solid catalyst, the polymerization activity of the solid catalyst may decrease depending on the drying conditions.

As a result of further studies based on such findings, the present inventors have found that a prepolymerized catalyst which is dried under specific conditions and has a volatile component amount of not more than a specific amount has excellent polymerization activity and The inventors have found that they have excellent fluidity and completed the present invention.

[0008]

The present invention has excellent olefin polymerization activity,
And it has a purpose to provide a method for producing a superior olefin polymerization dried prepolymerized catalyst flowability.

[0009]

SUMMARY OF THE INVENTION The method for producing a dry prepolymerization catalyst for olefin polymerization according to the present invention comprises (A) at least one selected from Group 2, Group 4, Group 12, Group 13 and Group 14 of the periodic table. Olefin was prepolymerized on a solid catalyst component in which (B) a transition metal compound of Group 4 of the Periodic Table and (C) an organoaluminum oxy compound are supported on a fine particle carrier made of an oxide of a certain element . The prepolymerization catalyst has an oxygen concentration of 20 ppm or less.
Circulation of inert gas with a water content of 20 ppm or less
It is dried at a temperature of 50 ° C. or below to reduce the amount of volatile components to 2.0.
The feature is that the content is less than or equal to weight% .

Since the dry prepolymerization catalyst for olefin polymerization of the present invention has excellent fluidity, it can be stably supplied to the polymerization reactor. Moreover, the dry prepolymerization catalyst for olefin polymerization of the present invention is excellent in olefin polymerization activity.

[0011]

The inert gas preferably used in the present invention uses a catalyst containing 20 to 40% by weight of copper and has a temperature of 0.
-100 ° C, pressure 1-30kg / cm ² -G, GHSV
Of 100 to 2000 hr ⁻¹ and then using a molecular sieve, the temperature is 0 to 100 ° C. and the pressure is 1
~30kg / cm ² -G, GHSV is 100~2000h
It can be obtained by processing under the condition of r ⁻¹ .

In the present invention, the inert gas treated as described above has an oxygen concentration of 20 ppm or less and a water content of 2 ppm.
It is preferably 0 ppm or less.

[0014]

[0015]

[0016]

DETAILED DESCRIPTION OF THE INVENTION Hereinafter, a specific description will be given about the manufacturing how olefin polymerization dried prepolymerized catalyst according to the present invention.

In the present specification, the term "polymerization" is sometimes used to mean not only homopolymerization but also copolymerization, and the term "polymer" refers to not only homopolymers but also homopolymers. In some cases, it is used in the sense of including a copolymer.

The dry prepolymerization catalyst for olefin polymerization according to the present invention comprises (A) a fine particle carrier on which (B) a transition metal compound of Group 4 of the periodic table and (C) an organoaluminum oxy compound are supported. Is a solid-state catalyst having an amount of volatile components of 2.0% by weight or less.

First, each component forming the dry prepolymerization catalyst for olefin polymerization according to the present invention will be described. The particulate carrier (A) used in the present invention is the second periodic table.
It is a fine-particle inorganic compound composed of an oxide of at least one element selected from Group 4, 4, 12, 13, and 14 .

Porous oxides are preferred as the finely divided inorganic compound, specifically SiO ₂ , Al ₂ O ₃ and Mg.
O, ZrO ₂ , TiO ₂ , B ₂ O ₃ , CaO, ZnO,
BaO, ThO _2, etc., or a mixture thereof or a mixture containing them and another oxide, for example, SiO ₂ —Mg
O, SiO ₂ -Al ₂ O ₃ , SiO ₂ -TiO ₂ , SiO _{2-
V 2 O 5, SiO 2 -Cr} 2 O 3, SiO 2 -TiO 2 -MgO
And the like. Among these, SiO ₂ ,
It is preferable that the main component is at least one component selected from the group consisting of Al ₂ O ₃ and MgO.
iO ₂ is preferred. These may be used in combination of two or more.

Particulate carrier (A) used in the present invention
Has a specific surface area of 50 to 1000 m ² / g, a pore volume of 0.3 to 2.5 cm ³ / g, and an average particle diameter of 1 to 300 μm. Is desirable.

Examples of the transition metal compound (B) of Group 4 of the periodic table used in the present invention include compounds containing a ligand having a cyclopentadienyl skeleton represented by the following general formula (I). You can

MLx (I) In the formula, M is 1 selected from transition metal atoms of Group 4 of the periodic table.
It represents a transition metal atom of the species, preferably zirconium, titanium or hafnium.

X is the valence of the transition metal atom M and represents the number of ligands L coordinated to the transition metal atom M. L is
A ligand or a group that coordinates to a transition metal atom M is shown, and at least one L is a ligand having a cyclopentadienyl skeleton, and L other than the ligand having the cyclopentadienyl skeleton. is a hydrocarbon group having 1 to 12 carbon atoms, a <br/> Turkey alkoxy group, an aryloxy group, a trialkylsilyl group,
SO ₃ R (provided that R is a hydrocarbon group having 1 to 8 carbon atoms which may have a substituent such as halogen), a halogen atom or a hydrogen atom. Two or more L may be the same as or different from each other.

Examples of the ligand having a cyclopentadienyl skeleton include cyclopentadienyl group; methylcyclopentadienyl group, dimethylcyclopentadienyl group, trimethylcyclopentadienyl group, tetramethylcyclopentadienyl group. Group, pentamethylcyclopentadienyl group, ethylcyclopentadienyl group, methylethylcyclopentadienyl group, propylcyclopentadienyl group, methylpropylcyclopentadienyl group, butylcyclopentadienyl group, methylbutylcyclo Examples include alkyldisubstituted cyclopentadienyl group such as pentadienyl group and hexylcyclopentadienyl group; indenyl group; alkyl-substituted indenyl group; 4,5,6,7-tetrahydroindenyl group; fluorenyl group, etc. it can.
These groups may be substituted with a halogen atom, a trialkylsilyl group or the like.

Of these ligands having a cyclopentadienyl skeleton, an alkyl-substituted cyclopentadienyl group is particularly preferable. When the compound represented by the general formula (I) includes two or more ligands having a cyclopentadienyl skeleton, the ligands having two cyclopentadienyl skeletons are ethylene and propylene. Or the like; a substituted alkylene group such as isopropylidene or diphenylmethylene; a silylene group; a dimethylsilylene group; a substituted silylene group such as a diphenylsilylene group or a methylphenylsilylene group.

Specific examples of the ligand 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, an aralkyl group, and the like. Specifically, the alkyl group includes a methyl group, an ethyl group, Examples include propyl group, isopropyl group, butyl group, etc., examples of cycloalkyl group include cyclopentyl group, cyclohexyl group, etc., examples of aryl group include phenyl group, tolyl group, etc., and examples of aralkyl group include benzyl group. Examples thereof include a group and a neophyll group.

The alkoxy group has from 1 to 1 carbon atoms.
Examples thereof include methoxy group, ethoxy group, butoxy group and the like. Examples of the aryloxy group include those having 6 to 20 carbon atoms, such as a phenoxy group.

Examples of the trialkylsilyl group include those having 3 to 21 carbon atoms in total, such as trimethylsilyl group and triethylsilyl group. Examples of the ligand represented by SO ₃ R include a p-toluenesulfonato group, a methanesulfonato group, and a trifluoromethanesulfonato group.

Halogen includes fluorine, chlorine, bromine,
Examples thereof include iodine. The transition metal compound (B) used in the present invention is more specifically represented by the following general formula (I ′) when the valence of the transition metal atom is 4, for example.

R ¹ R ² R ³ R ⁴ M (I ') In the formula, M is a transition metal atom similar to the above, and R ^{1 to} R
⁴ represents a ligand or a group which coordinates to the transition metal atom M.

R ¹ is a ligand having a cyclopentadienyl skeleton similar to L.

R ² , R ³ and R ^{4, which} may be the same or different from each other, have a ligand having a cyclopentadienyl skeleton similar to the above L, a hydrocarbon group having 1 to 12 carbon atoms, It is one kind of group or atom selected from the group consisting of an alkoxy group, an aryloxy group, a trialkylsilyl group, SO ₃ R, a halogen atom and a hydrogen atom.

In the present invention, a transition metal compound in which one of R ² , R ³ and R ^{4 in} the above general formula (I ′) is a ligand having a cyclopentadienyl skeleton, for example R ¹ and R ² is A transition metal compound which is a ligand having a cyclopentadienyl skeleton is preferably used. The ligands having these cyclopentadienyl skeletons are
It may be bonded via the above-mentioned bonding group. In this case, R ³ and R ⁴ are alkyl groups, cycloalkyl groups, aryl groups, aralkyl groups, alkoxy groups, aryloxy groups, trialkylsilyl groups, SO ₃ R, halogen atoms or hydrogen atoms.

Specific examples of the transition metal compounds in which M is zirconium among the compounds represented by the general liquid (I) are shown 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 (methanesulfonato), ethylenebis (indenyl) zirconium bis (p-toluenesulfonato), Ethylenebis (indenyl) zirconium bis (trifluoromethanesulfonate), ethylenebis (4,5,6,7-tetrahydroindenyl) zirconium dichloride, isopropyl Den (cyclopentadienyl-fluorenyl) zirconium dichloride, isopropylidene (cyclopentadienyl-methylcyclopentadienyl) zirconium dichloride, dimethylsilylene bis (cyclopentadienyl) zirconium dichloride, dimethylsilylene bis (methylcyclopentadienyl) ) Zirconium dichloride, dimethyl silylene bis (dimethylcyclopentadienyl) zirconium dichloride, dimethyl silylene bis (trimethylcyclopentadienyl) zirconium dichloride, dimethyl silylene bis (indenyl) zirconium dichloride, dimethyl silylene bis (indenyl) zirconium bis (trifluoromethane) Sulfonato), dimethylsilylene bis (4,5,6,7-tetrahydroindenyl) zirconium dichlorine , Dimethyl silylene (cyclopentadienyl-fluorenyl) zirconium dichloride, diphenyl silylene bis (indenyl) zirconium dichloride, methylphenyl silylene bis (indenyl) zirconium dichloride, bis (cyclopentadienyl) zirconium dichloride, bis (cyclopentadienyl) Zirconium dibromide, bis (cyclopentadienyl)
Methylzirconium monochloride, bis (cyclopentadienyl) ethylzirconium monochloride, bis (cyclopentadienyl) cyclohexylzirconium monochloride, bis (cyclopentadienyl) phenylzirconium monochloride, bis (cyclopentadienyl)
Benzyl zirconium monochloride, bis (cyclopentadienyl) zirconium monochloride, bis (cyclopentadienyl) methylzirconium monohydride, bis (cyclopentadienyl) dimethylzirconium, bis (cyclopentadienyl) diphenylzirconium, Bis (cyclopentadienyl) dibenzylzirconium, bis (cyclopentadienyl)
Zirconium methoxy chloride, bis (cyclopentadienyl) zirconium ethoxy chloride, bis (cyclopentadienyl) zirconium bis (methanesulfonato), bis (cyclopentadienyl) zirconium bis (p-toluenesulfonato), bis (cyclo Pentadienyl) zirconium bis (trifluoromethanesulfonato), bis (methylcyclopentadienyl) zirconium dichloride, bis (dimethylcyclopentadienyl)
Zirconium dichloride, bis (dimethylcyclopentadienyl) zirconium ethoxy chloride, bis (dimethylcyclopentadienyl) zirconium bis (trifluoromethanesulfonate), 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 (tetramethylcyclopentadienyl) zirconium dichloride,
Bis (pentamethylcyclopentadienyl) zirconium dichloride, bis (hexylcyclopentadienyl)
Zirconium dichloride, bis (trimethylsilylcyclopentadienyl) zirconium dichloride.

In the above example, the compound having a di-substituted cyclopentadienyl ring includes a compound having a 1,2- and 1,3-substituted cyclopentadienyl ring and has a tri-substituted cyclopentadienyl ring. The compounds include compounds having 1,2,3- and 1,2,4-substituted cyclopentadienyl rings. Alkyl groups such as propyl and butyl are n-,
Including isomers such as i-, sec-, and tert-.

In the present invention, as the transition metal compound (B),
In the zirconium compound as described above, a transition metal compound in which zirconium metal is replaced with titanium metal or hafnium metal can also be used.

These transition metal compounds (B) may be used alone or in combination of two or more.
It may be diluted with a hydrocarbon or a halogenated hydrocarbon before use.

In the present invention, as the transition metal compound (B), a zirconocene compound having a central transition metal atom of zirconium and having a ligand containing at least two cyclopentadienyl skeletons is preferably used.

Specific examples of the organoaluminum oxy compound (C) used in the present invention include conventionally known aluminoxanes and benzene-insoluble organoaluminum oxy compounds as exemplified in JP-A-2-78687. .

The conventionally known aluminoxane can be produced from the (D) organoaluminum compound described below, 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. A method of adding an organoaluminum compound such as trialkylaluminum to the hydrocarbon medium suspension described above and reacting the organoaluminum compound with adsorbed water or crystallization water. (2) A method in which water, ice or water vapor is allowed to directly act on an organoaluminum compound such as trialkylaluminum in a medium such as benzene, toluene, ethyl ether or tetrahydrofuran. (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 an organometallic component. Further, the solvent or the unreacted organoaluminum compound may be removed by distillation from the recovered solution of the aluminoxane, and then redissolved in the solvent or suspended in the poor solvent of the aluminoxane.

The dry prepolymerization catalyst for olefin polymerization according to the present invention comprises the above-mentioned (A) fine-particle carrier and (B)
It is a solid catalyst obtained by drying a prepolymerized catalyst obtained by prepolymerizing an olefin in the presence of a solid catalyst component carrying a transition metal compound and (C) an organoaluminum oxy compound.

FIG. 1 shows a process for preparing a dry prepolymerized catalyst for olefin polymerization according to the present invention. The solid catalyst component can be prepared by contacting the (A) fine-particle carrier with the (B) transition metal compound and (C) organoaluminum oxy compound.

The contact of the above components can be carried out in an inert hydrocarbon medium. Specific examples of such an inert hydrocarbon medium include propane, butane, pentane, hexane, heptane, octane, decane, Aliphatic hydrocarbons such as dodecane and kerosene; cyclopentane, cyclohexane,
Examples thereof include alicyclic hydrocarbons such as methylcyclopentane; aromatic hydrocarbons such as benzene, toluene and xylene; halogenated hydrocarbons such as ethylene chloride, chlorobenzene and dichloromethane, and mixtures thereof.

In preparing the solid catalyst component, (B)
The transition metal compound (transition metal atom conversion) is usually used in an amount of 0.001 to 1.0 mmol, preferably 0.01 to 0.5 mmol, per 1 g of the fine particle carrier (A),
(C) The organoaluminum oxy compound is usually 0.1 to
It is used in an amount of 100 mmol, preferably 0.5 to 20 mmol.

The solid catalyst component thus obtained is
In addition to the catalyst components as described above, other components useful for olefin polymerization such as an electron donor and a reaction aid may be contained, if necessary.

As a method for prepolymerizing an olefin in the presence of the above solid catalyst component, a conventionally known method is used,
For example, it can be carried out by introducing an olefin into an inert hydrocarbon medium in the presence of the above solid catalyst component. Examples of the inert hydrocarbon medium used for the preparation of the prepolymerization catalyst include the same ones as described above.

At the time of prepolymerization, the following (D) organoaluminum compound may be used together with the solid catalyst component. Specific examples of the organoaluminum compound used in the present invention as the (D) organoaluminum compound and also when preparing the aluminoxane as described above include trimethylaluminum, triethylaluminum, tripropylaluminum, triisopropyl. Trialkyl aluminum such as aluminum, tri-n-butyl aluminum, triisobutyl aluminum, tri sec-butyl aluminum, tri tert-butyl aluminum, tripentyl aluminum, trihexyl aluminum, trioctyl aluminum, tridecyl aluminum; tricyclohexyl aluminum, tri Tricycloalkyl aluminum such as cyclooctyl aluminum; dimethyl aluminum chloride, diethyl aluminum chloride, diethyl Rumi bromide, dialkyl aluminum halide such as diisobutyl aluminum chloride; diethylaluminum hydride, dialkylaluminum hydride such as diisobutylaluminum hydride; dimethyl aluminum methoxide, dialkylaluminum alkoxides such as diethylaluminum ethoxide;
Dialkyl aluminum aryloxides such as diethyl aluminum phenoxide and the like can be mentioned.

Of these, trialkylaluminums and tricycloalkylaluminums are preferable, trialkylaluminums are more preferable, and triethylaluminums and triisobutylaluminums are particularly preferable.

As the 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, z are each a positive number, and z ≧ 2x.) These are the combination of two or more It may be.

The organoaluminum compound (D) optionally used in the present invention may contain a small amount of a metal component other than aluminum. In the prepolymerized catalyst thus prepared, it is desirable that 0.5 to 300 g, preferably 1 to 200 g, and more preferably 2 to 100 g of the prepolymerized olefin polymer be present per 1 g of the solid catalyst component. .

The dry prepolymerized catalyst for olefin polymerization according to the present invention can be obtained by drying the above prepolymerized catalyst. Drying of the prepolymerized catalyst is usually carried out after removing the hydrocarbon as the dispersion medium from the obtained suspension of the prepolymerized catalyst by filtration or the like.

The prepolymerized catalyst is dried by flowing the prepolymerized catalyst under an inert gas at 50 ° C. or lower, preferably 20 to 40.
It is carried out by keeping the temperature in the range of ° C. The amount of volatile components of the obtained dry prepolymerized catalyst is 2.0% by weight or less,
It is preferably 1.0% by weight or less. The smaller the volatile component content of the dry prepolymerization catalyst, the better, and there is no particular lower limit, but it is 0.001% by weight for practical use. The drying time is usually 3 to 8 hours, depending on the drying temperature.

When the amount of volatile components of the dry prepolymerized catalyst exceeds 2.0% by weight, the fluidity of the dry prepolymerized catalyst is lowered,
It may not be possible to stably supply it to the polymerization reactor. The angle of repose of the dried prepolymerized catalyst is 50 ° or less, preferably 5 to 47 °, more preferably 10 to 45 °.
If the angle of repose of the dry prepolymerized catalyst exceeds 50 °, the fluidity of the dry prepolymerized catalyst may decrease, and it may not be possible to stably supply it to the polymerization reactor.

Here, the amount of volatile components of the dry prepolymerized catalyst is measured by, for example, a weight loss method or a method using gas chromatography.

In the weight loss method, the weight loss when the dry prepolymerized catalyst was heated at 110 ° C. for 1 hour in an inert gas atmosphere was calculated and expressed as a percentage with respect to the dry prepolymerized catalyst before heating.

In the method using gas chromatography, volatile components such as hydrocarbons are extracted from the dried prepolymerized catalyst, a calibration curve is prepared according to the internal standard method, and then the weight percent is calculated from the GC area.

As a method for measuring the amount of volatile components of the dry prepolymerized catalyst, the weight reduction method is adopted when the amount of volatile components of the dried prepolymerized catalyst is about 1% by weight or more. Is about 1% by weight or less, a method using gas chromatography is adopted.

Examples of the inert gas used for drying the prepolymerization catalyst include nitrogen gas, argon gas and neon gas. Such an inert gas has an oxygen concentration of 2
0 ppm or less, preferably 10 ppm or less, more preferably 5 ppm or less and a water content of 20 ppm or less,
It is preferably 10 ppm or less, more preferably 5 ppm or less. If the oxygen concentration and the water content in the inert gas exceed the above ranges, the olefin polymerization activity of the dry prepolymerization catalyst may be significantly reduced.

For the inert gas having an oxygen concentration of 20 ppm or less and a water content of 20 ppm or less, for example, a commercially available inert gas is contact-treated with a catalyst containing 20 to 40% by weight of copper, and then a molecular weight is set. It can be obtained by contact treatment with a sieve.

Used in treating the inert gas
As the copper-containing catalyst, water containing 20 to 40% by weight of copper is used.
More specifically, basic addition catalysts, deoxidation catalysts, etc.
Is a copper-chromium catalyst (for example, Cu; 35% by weight, C
r; 31% by weight, Ba; 2% by weight, Mn; 2.5% by weight
%), A copper-based catalyst in which copper is supported on silica (for example, Si
O ₂50 to 65% by weight, Cu; 16 to 30% by weight)
Which can be mentioned.

Such a catalyst is R3-11 (BASF
Company), G-99B, G-108A, G-108B (Ni
ssan-Girdler) and the like. Inactive
Contacting the gas with a catalyst containing 20-40% by weight of copper
In this case, the temperature is 0 to 100 ° C, preferably 0 to 50 ° C.
Range, pressure is 1-30 kg / cm ²-G, preferably
Is 1 to 10 kg / cm²-G range, GHSV is 1
00-2000 hr^-1, Preferably 200 to 2000 h
r^-1, More preferably 200 to 400 hr^-1In the range of
Is desirable.

[0064] Here, "GHSV" is used to mean a gas space velocity per unit time, the reactor volume the volume rate of the feed gas (m ³ / hr) at a temperature and pressure during the reaction (m ³⁾ It is divided by and the unit becomes hr ^-1 . The reactor volume at this time is an empty volume not filled with a catalyst.

The molecular sieve used for preparing the inert gas has a bulk density of 0.6 to 0.9.
g / cm ³ is preferable, and such molecular sieves are commercially available as Zeolum A-3, Zeolum A-4 (trade name, manufactured by Tosoh), Molecular Sieve 3A, molecular sieve 4A (trade name, manufactured by Nippon Unicar). Has been done.

Contact the inert gas with the molecular sieve.
When touched, the temperature is 0 to 100 ° C., preferably 0 to
It is in the range of 50 ° C and the pressure is 1 to 30 kg / cm.²-G,
Preferably 1-10 kg / cm²-G range, GH
SV is 100 ~ 2000hr ^-1, Preferably 200-2
000hr^-1, More preferably 200 to 400 hr^-1of
It is desirable that it is in the range.

As described above, the inert gas used for drying the prepolymerized catalyst is a catalyst containing 20 to 40% by weight of copper, and the temperature is 0 to 100 ° C. and the pressure is 1 to 30 kg / cm ^2-.
G, GHSV 100-2000 hr ^-1 , after treating with a molecular sieve, the temperature 0-100 ℃,
Pressure 1 to 30 kg / cm ² -G, GHSV 100 to 200
It is preferable that the oxygen concentration is 20 ppm or less and the water content is 20 ppm or less by treating under the condition of ⁰ hr ⁻¹ .

Since the dry prepolymerization catalyst for olefin polymerization according to the present invention has excellent fluidity, it can be stably supplied to the polymerization reactor. Also, olefin can be (co) polymerized with excellent polymerization activity.

In the olefin gas phase polymerization method according to the present invention, when the olefin is polymerized in the gas phase while continuously supplying the solid catalyst and the olefin to the polymerization reactor (fluidized bed reactor), The dry prepolymerization catalyst for olefin polymerization is supplied to the polymerization reactor in a solid powder state to polymerize olefins. In the polymerization, the above-mentioned (D) is used together with this dry prepolymerization catalyst for olefin polymerization.
Organoaluminum compounds can also be used. (D)
The organoaluminum compound is usually used in an amount of 1 to 1000 mol, preferably 2 to 300 mol, based on 1 mol of the transition metal atom in the transition metal compound (B) contained in the dry prepolymerization catalyst for olefin polymerization. Is desirable.

The polymerization reaction can be carried out by any of a batch system, a semi-continuous system and a continuous system. It is also possible to carry out the polymerization in two or more stages under different reaction conditions. In the present invention, it is preferable to employ a continuous fluidized bed gas phase polymerization method.

The polymerization temperature in the gas phase polymerization method is usually 50.
The temperature is in the range of to 120 ° C, preferably 60 to 100 ° C.
The polymerization pressure is usually normal pressure to 100 kg / cm ^2, a range preferably from normal pressure to 50 kg / cm ^2. The gas linear velocity is
0.4-1.5 m / sec, preferably 0.6-1.2
It is in the range of m / sec.

The olefin gas phase polymerization method according to the present invention will now be described in detail with reference to FIG. The dry prepolymerized catalyst (solid catalyst) 1 for olefin polymerization as described above is continuously supplied to the fluidized bed reactor 3 via a line 2 in a solid powder state.

The solid catalyst 1 is usually 0.00001 to 1.0 mmol / hour, preferably 0.0001 to 0.03, in terms of the transition metal atom in the transition metal compound (A) per liter of polymerization volume. It is preferably used in an amount of 1 mmol / hour.

The gaseous olefin is fed to the fluidized bed reactor 3,
For example, the lower part thereof is continuously blown by a gas blower 7 via a line 6. The olefin is supplied to the gas blower 7 from the olefin supply line 9. The olefin blown into the lower part of the fluidized bed reactor 3 passes through a gas dispersion plate 4 such as a porous plate to disperse the solid catalyst 1 and form a fluidized bed (reaction system) 5. In the fluidized bed 5, the olefin is (co) polymerized to produce a particulate olefin (co) polymer. In this way, the olefin supplied to the reactor 3 also serves as a fluidizing gas for keeping the catalyst particles in the reaction system in a fluidized state. It is also possible to use a gas mixture of an olefin and an inert gas such as nitrogen as the fluidizing gas. The produced polymer particles are continuously withdrawn from the fluidized bed reactor 3 via the polymer recovery line 11.

On the other hand, the gaseous unreacted olefin which has passed through the fluidized bed 5 is decelerated in the deceleration zone 3a provided in the upper portion of the fluidized bed reactor 3 and then comes out of the fluidized bed reactor 3. . The unreacted olefin emerging from the fluidized bed reactor 3 can be circulated through a circulation line 10 together with fresh olefin from the olefin supply line 9. The heat of polymerization of unreacted olefin is preferably removed by the heat exchanger 8 before being recycled. However, the heat of polymerization can also be used to heat fresh olefin before it is fed to the reactor 3. Although the heat exchanger 8 is shown downstream of the blower 7 in FIG. 2, it may be arranged upstream of the blower 7.

As described above, the polymerization method of the present invention can be operated continuously.

The molecular weight of the obtained olefin polymer can be adjusted by allowing a molecular weight modifier such as hydrogen to be present in the polymerization system or by changing the polymerization temperature. Hydrogen may be supplied anywhere in the gas phase fluidized bed reactor, for example line 10.

The olefin used in the present invention is preferably an α-olefin having 2 to 18 carbon atoms, such as ethylene, propylene, 1-butene,
1-pentene, 1-hexene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, 1-tetradecene , 1-hexadecene, 1-octadecene and the like.

Furthermore, cyclopentene, cycloheptene, norbornene, 5-methyl-2-norbornene, tetracyclododecene, 2-methyl 1,4,5,8-dimethano-1,2,3,4,4
Also included are monocyclic and polycyclic olefins such as a, 5,8,8a-octahydronaphthalene, and aromatic and alicyclic vinyl compounds such as styrene, vinyltoluene and vinylcyclohexane.

In addition to olefins, butadiene, isoprene, 1,4-hexadiene, dicyclopentadiene,
It is also possible to copolymerize polyenes such as 5-ethylidene-2-norbornene.

In the present invention, among these, it is preferable to copolymerize ethylene and an α-olefin having 3 to 18 carbon atoms to produce a linear low density polyethylene (LLDPE). In the present invention, among the olefin polymers, particularly, a structural unit derived from ethylene is contained in a proportion of 75 to 98% by weight, preferably 80 to 97% by weight, and derived from an α-olefin having 3 or more carbon atoms. The constituent units
A low crystalline ethylene / α-olefin copolymer, so-called linear low density polyethylene (LLDPE), which is contained in a proportion of 3 to 25% by weight, preferably 3 to 20% by weight, is particularly preferably produced.

[0082]

The dry prepolymerization catalyst for olefin polymerization according to the present invention comprises (A) a fine particle carrier and (B) a periodic table
A prepolymerization catalyst prepared by prepolymerizing an olefin on a solid catalyst component carrying a group C transition metal compound and (C) an organoaluminum oxy compound, wherein the volatile component in the prepolymerization catalyst is 2% by weight. Since it is below, the fluidity is excellent, and the supply to the polymerization reactor can be stably performed. Further, such a catalyst has excellent olefin polymerization activity.

The method for producing a dry prepolymerized catalyst for olefin polymerization according to the present invention can produce a dry prepolymerized catalyst having excellent fluidity without lowering the olefin polymerization activity.

Since the olefin polymerization method according to the present invention polymerizes olefins in the gas phase while supplying the dry prepolymerization catalyst for olefin polymerization in a solid powder state to the polymerization reactor, it has excellent polymerization activity. Olefin can be stably polymerized over a long period of time. Further, since the catalyst is not supplied to the polymerization reactor in the state of suspension of hydrocarbon, the polymerization temperature range is wider than before.

[0085]

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

In this specification, the amount of volatile components and the angle of repose were measured as follows. [Amount of Volatile Components] Pretreatment of Sample 0.5 g of a sample was weighed and extracted with 30 ml of acetone while cooling with dry ice acetone, and then an acetone solution of methyl benzoate as an internal standard 0.05 g / 5
Add ml. 1 ml of 13% aqueous ammonia is added, and then acetone is added to make 50 ml. Filter the sample with a 0.2 μm filter. Analytical method Take 1 microliter of the pretreated sample,
A hydrocarbon having 6 to 10 carbon atoms is detected as a volatile component by gas chromatography. The content of volatile components is calculated from the GC area after creating a calibration curve according to the internal standard method, and is expressed as% by weight. Measurement conditions Column; fused silica capillary column DB-WAX (J &
W company, 122-7062) Column length; 0.25 mmφ × 60 m df = 0.25
μm Column temperature: 50 ° C. → 230 ° C. (holding time 2 minutes, temperature rise 1
Detector; FID carrier gas; helium split ratio; 1:65 split flow rate; 73 ml / min.

[Angle of repose] The angle of repose is Seishin Enterprise Co., Ltd.
It was measured by the discharge method using a multi-tester MT-1000 ^™ . That is, the dry prepolymerized catalyst was dropped from the upper funnel onto the measurement table, and the angle (repose angle) of the slope of the conical mountain of the dry prepolymerized catalyst deposited on the table was measured. At this time, the angle was measured at three or more points, and the value obtained by arithmetically averaging those values was defined as the angle of repose. The smaller the angle of repose, the better the fluidity of the dry prepolymerized catalyst.

[0088]

Example 1 [Preparation of solid catalyst component] 10 kg of silica (SiO ₂ ) dried at 250 ° C. for 10 hours was suspended in 154 liters of toluene and then cooled to 0 ° C. To this suspension, 50.5 liters of a methylaminooxane toluene solution (Al = 1.52 mol / liter) was added dropwise over 1 hour. At this time, the temperature in the system was kept at 0 to 5 ° C. Continued 0
React at ℃ for 30 minutes, then over 95 hours at 95 ℃
The temperature was raised to, and the reaction was carried out at that temperature for 4 hours. Then 60
The temperature was lowered to ℃, and the supernatant was removed by decantation. The solid component thus obtained was washed twice with toluene and then resuspended in 100 liters of toluene to make the total volume 160 liters.

To the obtained suspension, a solution of bis (1,3-n-butylmethylcyclopentadienyl) zirconium dichloride in toluene (Zr = 25.7 mmol / liter) was added.
2.0 liter was added dropwise at 80 ° C. over 30 minutes, and the reaction was further performed at 80 ° C. for 2 hours. Then, the supernatant was removed and the solid was washed twice with hexane to obtain a solid catalyst component containing 3.2 mg of zirconium per 1 g of silica.

[Preparation of Prepolymerized Catalyst] The solid catalyst component of 7.0 k was placed in a 350 liter reactor which was sufficiently replaced with nitrogen.
g and hexane were charged to bring the total volume to 285 liters. After cooling the system to 10 ° C, ethylene was added to 8 Nm ³
Bubbling into the hexane suspension of the solid catalyst component for 5 minutes at a flow rate of / hr. During this time, the temperature in the system was maintained at 10 to 15 ° C. Then, the supply of ethylene was stopped, and 2.4 mol of triisobutylaluminum and 1.2 kg of 1-hexene were charged. After making the system a closed system, 8 Nm ³
The ethylene feed was restarted at a flow rate of / hr. After 15 minutes, the flow rate of ethylene was reduced to 2 Nm ³ / hr and the pressure in the system was set to 0.8 kg / cm ² -G. During this time, the temperature in the system rose to 35 ° C. After that, the temperature in the system is set to 32 to
While controlling at 35 ° C, ethylene was added at 4 Nm ³ /
It was supplied at a flow rate of hr for 3.5 hours. During this time, the pressure in the system was maintained at 0.7 to 0.8 kg / cm ² -G. Then
The system was replaced with nitrogen, the supernatant was removed, and the mixture was washed twice with hexane. Thus, a prepolymerized catalyst in which 3 g of the polymer was prepolymerized per 1 g of the solid catalyst component was obtained.
[Η] of this prepolymerized polymer was 2.1 dl / g, and the content of 1-hexene was 4.8% by weight.

The supernatant liquid after the prepolymerization was colorless and transparent, the prepolymerization catalyst had a good shape, and the bulk density was 0.4 g / cm ³ . [Drying of Prepolymerized Catalyst] 20 kg of the hexane suspension of the prepolymerized catalyst obtained above was charged as a prepolymerized catalyst amount into a jacketed filter dryer having an inner volume of 130 liters,
Hexane was filtered. Then, the jacket was heated to 40 ° C., and the system was dried for 3 hours while nitrogen gas (oxygen concentration 10 ppm, water content 5 ppm) was aerated at 6 Nm ³ / hr. During that time, the temperature in the system rose from 20 ° C to 35 ° C. By this operation, the volatile component was 0.1% by weight, the bulk density was 0.40 g / cm ³ , and the angle of repose was 3
A dry prepolymerized catalyst having an angle of 8.1 ° was obtained.

[Gas phase polymerization] Using a continuous fluidized bed gas phase polymerization apparatus, ethylene and 1-hexene were mixed at a total pressure of 20 kg / cm ² -G, a polymerization temperature of 85 ° C. and a gas linear velocity of 0.7 m / sec. Copolymerization was performed. 60 g / dry prepolymerized catalyst prepared above
It was continuously fed at a rate of hr and ethylene, 1-hexene, hydrogen and nitrogen were continuously fed in order to maintain a constant gas composition during the polymerization (gas composition; 1-hexene / ethylene = 0.025 , Hydrogen / ethylene = 1.5 × 10 ⁻⁴ , ethylene concentration = 71%).

The obtained ethylene / 1-hexene copolymer had a yield of 80 kg / hr and a density of 0.91 g / c.
m ³ and a melt flow rate (MFR) of 0.61
g / 10 min, the bulk density is 0.44 g / cm ³ ,
The average particle size of the polymer particles is 1050 μm,
The proportion of finely divided polymer having a particle size of μm or less was 0.1% by weight or less.

After continuous polymerization for 10 days, the inner wall of the polymerization apparatus and the dispersion plate were inspected and no adhering polymer was found.

[0095]

Example 2 Oxygen concentration was 25 pp for drying the prepolymerized catalyst.
A dry prepolymerized catalyst having a volatile content of 0.1% by weight was prepared in the same manner as in Example 1 except that nitrogen gas of m was used, and the dry prepolymerized catalyst was used in the same manner as in Example 1. As a result of copolymerizing ethylene and 1-hexene, the yield was 56 kg / hr.

[0096]

Example 3 As a nitrogen gas for drying the prepolymerization catalyst, a nitrogen gas having an oxygen concentration of 25 ppm was first prepared by BASF.
A reaction tube filled with 25 liters of R3-11 at 40 ° C, 1
The adsorption tube filled with 25 liters of molecular sieve (Zeorum A-3, manufactured by Tosoh Corp.) was passed under the conditions of atmospheric pressure and GHSV 300 hr ^-1 at 40 ° C., 1 atmospheric pressure, GHS.
Example 1 except that nitrogen gas having an oxygen concentration of 5 ppm and a water content of 3 ppm was used under the condition of V 300 hr ^-1.
A dry prepolymerized catalyst was prepared in the same manner as above, and the copolymerization of ethylene and 1-hexene was carried out in the same manner as in Example 1 except that this dry prepolymerized catalyst was used. As a result, the yield was 82 kg.
It was / hr.

[0097]

Example 4 [Drying of Preliminary Polymerization Catalyst] 20 kg of the hexane suspension of the prepolymerization catalyst obtained in Example 1 as a prepolymerization catalyst amount was put into a filtration dryer with a jacket having an inner volume of 130 liters, and hexane was added. Filtered. After that, the jacket is 40 ℃
The temperature was raised to 3, and nitrogen gas (oxygen concentration 10 ppm, water content 7 ppm) was aerated at 6 Nm ³ / hr to dry the system for 3 hours. During that time, the temperature in the system rose from 20 ° C to 35 ° C. By this operation, the volatile component was 0.1% by weight, the bulk density was 0.40 g / cm ³ , and the angle of repose was 3
A dry prepolymerized catalyst having a 9.3 ° was obtained.

[Gas Phase Polymerization] Ethylene and 1- were prepared in the same manner as in Example 1 except that the dry prepolymerized catalyst prepared above was used.
Polymerized with hexene.

The obtained ethylene / 1-hexene copolymer had a yield of 78 kg / hr and a density of 0.91 g / c.
m ³ , the MFR is 0.65 g / 10 min, the bulk density is 0.43 g / cm ³ , the average particle size of the polymer particles is 1000 μm, and the ratio of the fine powder polymer of 100 μm or less is 0.1. It was less than weight%.

After continuous polymerization for 10 days, the inner wall of the polymerization apparatus and the dispersion plate were inspected and no adhering polymer was found.

[0101]

Comparative Example 1 [Drying of Preliminary Polymerization Catalyst] 20 kg of the hexane suspension of the prepolymerization catalyst obtained in Example 1 as a prepolymerization catalyst amount was put into a filtration dryer with a jacket having an inner volume of 130 liters, and hexane was added. Filtered. After that, the jacket is 40 ℃
The temperature was raised to 1, and nitrogen gas (oxygen concentration 10 ppm, water content 5 ppm) was aerated at 6 Nm ³ / hr for 1 hour while being aerated. During that time, the temperature in the system rose from 20 ° C to 22 ° C. By this operation, the volatile component was 3% by weight, the bulk density was 0.33 g / cm ³ , and the angle of repose was 6
A dry prepolymerized catalyst having a 0.5 ° was obtained.

[Gas Phase Polymerization] Ethylene and 1- were prepared in the same manner as in Example 1 except that the dry prepolymerized catalyst prepared above was used.
An attempt was made to polymerize with hexene, but the fluidity of the dry prepolymerization catalyst was poor and it could not be continuously supplied to the polymerization reactor.

[0103]

Example 5 [Preparation of Prepolymerized Catalyst] 10 kg of silica (SiO ₂ ) dried at 250 ° C. for 10 hours was suspended in 154 liters of toluene and then cooled to 0 ° C. To this suspension, 44.1 liters of a methylaminooxane toluene solution (Al = 1.52 mol / liter) was added dropwise over 1 hour. At this time, the temperature in the system was kept at 0 to 5 ° C. Continued 0
React at ℃ for 30 minutes, then over 95 hours at 95 ℃
The temperature was raised to, and the reaction was carried out at that temperature for 4 hours. Then 60
The temperature was lowered to ℃, and the supernatant was removed by decantation. The solid component thus obtained was washed twice with toluene and then resuspended in 100 liters of toluene to make the total volume 160 liters.

62 liters of the resulting suspension was transferred to another reactor and another 75 liters of toluene were added. Then, rac-dimethylsilylenebis {1- (2-methyl
After adding 50 g of -4,5-benzoindenyl)} zirconium dichloride and stirring for 20 minutes, 270 liters of hexane and 4.35 mol of triisobutylaluminum were added. Subsequently, propylene was added at 8 kg / hr. Pre-polymerization was carried out at 20 ° C. for 2 hours while feeding at a rate of. After 2 hours, the supply of propylene was stopped and the reaction was continued for another 30 minutes. Then, the system was replaced with nitrogen, the supernatant was removed, and the system was washed with hexane three times. In this way, a prepolymerized catalyst in which about 3 g of the polymer was prepolymerized per 1 g of the solid catalyst component was obtained.

[Drying of Prepolymerized Catalyst] The prepolymerized catalyst was dried in the same manner as in Example 1 except that the above prepolymerized catalyst was used. As a result, the volatile component was 0.2% by weight, the bulk density was 0.40 g / cm ³ , and the angle of repose was 36.0 °.
To obtain a dry prepolymerized catalyst.

[0106]

Comparative Example 2 [Drying of Prepolymerized Catalyst] The prepolymerized catalyst obtained in Example 5 was dried in the same manner as in Comparative Example 1. As a result, the volatile component was 2.8% by weight and the bulk density was 0.34 g / c.
m ³ and a repose angle of 58.9 ° were obtained.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a process for preparing a dry prepolymerized catalyst for olefin polymerization according to the present invention.

FIG. 2 is a schematic diagram showing an example of a gas phase fluidized bed reactor capable of polymerizing olefins according to the present invention.

[Explanation of symbols]

1 ... Solid catalyst 3 ... Fluidized bed reactor 3a… Deceleration area 4 ... Gas dispersion plate 5 ... Fluidized bed 7 ... Blower 8 ... Heat exchanger 9 ... Olefin supply line 10… Circulation line 11… Polymer recovery line

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Kenji Doi Inventor Kenji Doi 6-1-2 Waki, Waki-cho, Kuga-gun, Yamaguchi Prefecture Mitsui Petrochemical Industries, Ltd. (72) In Hisataka Suzuki, Kuga-gun, Yamaguchi Prefecture Waki-cho 6-1-2 Waki, Mitsui Petrochemical Industry Co., Ltd. (56) Reference JP-A-8-100017 (JP, A) JP-A-63-152608 (JP, A) JP-A-9-506135 (JP, A) International publication 93/023439 (WO, A1) International publication 94/028034 (WO, A1) (58) Fields investigated (Int.Cl. ⁷ , DB name) C08F 4/64-4/658

Claims (2)

(57) [Claims] 1. (A) Periodic Table Group 2, Group 4, Group 12 and Group 13
A solid in which (B) a transition metal compound of Group 4 of the periodic table and (C) an organoaluminum oxy compound are supported on a particulate carrier made of an oxide of at least one element selected from Group 14 and Group 14 The prepolymerized catalyst obtained by prepolymerizing the olefin with the catalyst component is dried at a temperature of 50 ° C. or lower under the flow of an inert gas having an oxygen concentration of 20 ppm or less and a water content of 20 ppm or less to reduce the amount of volatile components. 2.0
A method for producing a dry prepolymerization catalyst for olefin polymerization, characterized in that the content thereof is at most% by weight. 2. The inert gas contains copper in an amount of 20 to 40% by weight.
Using a catalyst containing, the temperature is 0 ~ 100 ℃, the pressure is 1 ~ 3
0kg / cm ² -G, GHSV is 100 ~ 2000hr ^-1
After the treatment under the conditions of 1), the temperature is 0 to 100 ° C and the pressure is 1 to 30 kg / cm ² -G, G using a molecular sieve.
The method for producing a dry prepolymerized catalyst for olefin polymerization according to claim 1, which is obtained by treating HSV under a condition of 100 to 2000 hr ^-1 .