JPH0776604A - Vapor phase polymerization of olefin - Google Patents

Abstract

PURPOSE:To stably obtain an olefin polymer in a high yield excellent in fluidity and particle characteristics by feeding a fluidized bed reactor with an olefin together with water, an alcohol, ketone, etc., in the presence of a solid group IV-B metallocene catalyst followed by conducting a vapor phase polymerization. CONSTITUTION:A fluidized bed reactor 3 is fed with a solid group IV-B metallocene catalyst 1 via a line 2, and an olefin together with water and at least one kind of compound among alcohols and ketones, etc., are blown, by a circulating gas blower 7, via a circulating line 6 from the lower part of the reactor 3 via a gas diffuser 4 such as a porous plate into the reactor 3 to maintain the fluidized bed (reaction system) 5 in a fluidized state to conduct a vapor phase polymerization of the olefin. The polymer particles produced are then continuously drawn from the reactor 3 via a line 11 to obtain the olefin polymer <=95 in the falling time index X (sec) defined by the formula (to is falling time (sec) in the case of the olefin polymer alone; t is falling time (sec) in the case of medium presence).

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD OF THE INVENTION The present invention relates to a gas phase polymerization method for olefins, and more particularly to a method for continuously carrying out gas phase polymerization of olefins using a fluidized bed reactor in the presence of a metallocene catalyst. Olefin (co) polymers that have excellent fluidity of olefin polymers produced in a fluidized bed can be stably produced for a long period of time without generating lumps, sheets, etc. It relates to a gas phase polymerization method.

[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.

Such an olefin polymer has hitherto been obtained by a solution polymerization method, a suspension polymerization method or a gas phase polymerization method in the presence of a titanium-based solid catalyst component containing magnesium, titanium and halogen as essential components. Is produced by (co) polymerizing.

By the way, when the above-mentioned polymerization is carried out by a gas phase polymerization method, the polymer can be obtained in the form of particles, and the step of precipitating particles or the step of separating particles after the polymerization becomes unnecessary. Therefore, it is known that the manufacturing process can be simplified and the manufacturing cost can be reduced.

In such a gas phase polymerization method, a solid catalyst and an olefin are continuously supplied to a fluidized bed reactor,
In this method, olefin is polymerized or copolymerized in a fluidized bed, and the resulting particulate polymer is continuously extracted to continuously (co) polymerize the olefin.

When an olefin (co) polymer is produced using such a fluidized bed reactor, the fluidity of the produced olefin (co) polymer in the fluidized bed is lowered, and the mixture in the fluidized bed is reduced. In some cases, the condition became non-uniform and stable operation could not be performed for a long period of time. Further, when the fluidity of the olefin (co) polymer produced is lowered, the fluidity of the olefin (co) polymer is inferior even after being discharged from the fluidized bed reactor.
In a polymer discharge device or an olefin (co) polymer drying device, the (co) polymer particles may be blocked or bridged, and the discharge operation may not be performed smoothly.

[0007] Such a tendency tends to be more prominent especially when a linear low density polyethylene (LLDPE) is produced by copolymerizing ethylene and α-olefin. That is, for example, ethylene and α-olefin are copolymerized to form a linear low-density polyethylene (LLDP).
When producing E), etc., due to the adhesiveness of the produced polymer, the produced polymer particles adhere to each other to form a polymer mass, or the polymer particles adhere to the inner wall of the device or the gas dispersion plate in the device, etc. In some cases, the polymer was generated to cause clogging of the gas dispersion plate, which reduced the fluidity of the fluidized bed, and forced to stop the operation.

Conventionally, the solid titanium-based catalyst components as described above have been known as catalysts capable of highly active gas phase polymerization of olefins. In recent years, however, (co) polymerization of olefins with higher polymerization activity is known. As a catalyst that can be
A catalyst comprising a solid catalyst component containing a metallocene compound of Group IVB metal such as zirconium and an organoaluminum component has been developed. In order to stably carry out gas phase polymerization of olefins for a long period using such a highly active solid metallocene catalyst, it is desired that the fluidity of the fluidized bed (reaction system) is stable.

Therefore, in the presence of the metallocene catalyst,
Olefin (co) polymers with excellent particle properties such as excellent fluidity in the fluidized bed can be stably produced over a long period of time without generating polymer lumps when continuously polymerizing olefins in the gas phase. The advent of a process for the gas phase polymerization of olefins that can be done is desired.

The present inventor has conducted research on a method capable of stably and continuously operating gas phase polymerization of an olefin using such a highly active metallocene catalyst for a long period of time.
When at least one compound selected from water, alcohol or ketone is added to the fluidized bed (reaction system) to carry out the gas phase polymerization reaction, the fluidity of the olefin (co) polymer powder in the fluidized bed is prolonged. The present invention has been completed by finding that an olefin (co) polymer that can be stably held over a long period of time, can be continuously operated for a long time, and that has excellent fluidity can be obtained.

[0011]

It is an object of the present invention to provide an olefin (co) polymer having excellent particle properties such as excellent fluidity in a fluidized bed without producing polymer lumps in the continuous vapor phase polymerization of olefins. It is an object of the present invention to provide a gas phase polymerization method of an olefin, which can be stably produced in a high yield for a long period of time.

[0012]

SUMMARY OF THE INVENTION The process for vapor phase polymerization of olefins according to the present invention is carried out by continuously supplying olefins in the presence of a solid Group IVB metallocene catalyst using a fluidized bed reactor to carry out gas phase polymerization. , Olefin, and at least one compound selected from water, alcohol or ketone are supplied to the fluidized bed reactor to polymerize or copolymerize the olefin, and the number of seconds for dropping the olefin polymer defined as follows: It is characterized by producing an olefin polymer having an index X of 95 or less, preferably 90 or less, particularly preferably 80 or less.

[0013]

[Equation 2]

(In the formula, to is the number of seconds of dropping of the olefin polymer obtained when neither water, alcohol nor ketone is added to the reactor, and t is at least selected from water, alcohol or ketone in the reactor. It is the number of seconds of dropping of the olefin polymer obtained when one compound is added.) By supplying at least one compound selected from water, alcohol or ketone to the fluidized bed reactor, The temperature fluctuation can be kept within 5 ° C.

In the present invention, at least one compound selected from the above-mentioned water, alcohol or ketone is
Based on the total amount (gram atom) of aluminum contained in the organoaluminum component (the total amount of the organoaluminum oxy compound and the organoaluminum compound) as a catalyst,
0.03-3 mol / 1 gram atom, preferably 0.1
0.3 mol / 1 gram atom, more preferably 0.1
It is desirable to be provided in an amount of 2 mol / 1 gram atom, in particular 0.1-1.5 mol / 1 gram atom, more especially 0.25-1.5 mol / 1 gram atom.

In the present invention, it is preferable to produce linear low density polyethylene (LLDPE) by copolymerizing ethylene and an α-olefin having 3 to 18 carbon atoms.

[0017]

DETAILED DESCRIPTION OF THE INVENTION The olefin gas phase polymerization method according to the present invention will be specifically described below. In the present invention, the term "polymerization" may be used to mean not only homopolymerization but also copolymerization, and the term "polymer" includes not only homopolymer but also copolymer. May be used with the intention.

First, the solid group IVB metallocene catalyst used in the gas phase polymerization method for olefins according to the present invention will be described. The solid group IVB metallocene catalyst used in the present invention is a group IVB transition metal compound containing a ligand having an [A] cyclopentadienyl skeleton, a [B] organoaluminum oxy compound, and [C] particles. And a carrier.

The transition metal compound of Group IVB (hereinafter sometimes referred to as metallocene compound [A]) containing a ligand having an [A] cyclopentadienyl skeleton used in the present invention is represented by the following formula [I]: ]] Is represented.

ML _x [I] [In the formula, M is a transition metal atom of Group IVB, specifically, zirconium, titanium or hafnium, and L
Is a ligand that coordinates to a transition metal atom, and at least 1
L is a ligand containing a ligand having a cyclopentadienyl skeleton, and L other than the ligand containing a ligand having a cyclopentadienyl skeleton is a hydrocarbon having 1 to 12 carbon atoms. A group, an alkoxy group, an aryloxy group, a trialkylsilyl group, an SO ₃ R group (wherein 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. And x is the valence of the transition metal atom. Examples of the ligand containing a ligand having a cyclopentadienyl skeleton include, for example, a cyclopentadienyl group, a methylcyclopentadienyl group, a dimethylcyclopentadienyl group, a trimethylcyclopentadienyl group, and tetramethyl. Cyclopentadienyl group, pentamethylcyclopentadienyl group, ethylcyclopentadienyl group, methylethylcyclopentadienyl group, propylcyclopentadienyl group, methylpropylcyclopentadienyl group, butylcyclopentadienyl group , An alkyl-substituted cyclopentadienyl group such as a methylbutylcyclopentadienyl group and a hexylcyclopentadienyl group or an indenyl group, a 4,5,6,7-tetrahydroindenyl group, and a fluorenyl group can be exemplified. . These groups may be substituted with a halogen atom, a trialkylsilyl group or the like.

Of these ligands which coordinate to the transition metal atom, an alkyl-substituted cyclopentadienyl group is particularly preferable. When the compound represented by the general formula [I] contains two or more groups having a cyclopentadienyl skeleton,
Groups having two cyclopentadienyl skeletons are 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. May be bonded via a substituted silylene group of

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, and iodine.

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

R ¹ _a R ² _b R ³ _c R ⁴ _d M ... [I '] [In the formula [I'], M is the same transition metal atom as in the formula [I], and R ¹ is cyclopentadienyl. A group (ligand) having a skeleton, wherein R ² , R ³ and R ⁴ are a group having a cyclopentadienyl skeleton, an alkyl group, a cycloalkyl group,
An aryl group, an aralkyl group, an alkoxy group, an aryloxy group, a trialkylsilyl group, a SO ₃ R group, a halogen atom or a hydrogen atom, and a is an integer of 1 or more, a
+ B + c + d = 4. In the present invention, in the above formula [I ′], R ¹ , R ² , R ³
And at least two of R ⁴ such as R ¹ and R
^A metallocene compound in which ² is a group (ligand) having a cyclopentadienyl skeleton is preferably used.

These cyclopentadienyl skeleton-containing groups are alkylene groups such as ethylene and propylene, substituted alkylene groups such as isopropylidene and diphenylmethylene, silylene groups or substituted silylene groups such as dimethylsilylene, diphenylsilylene and methylphenylsilylene groups. It may be bound via a group or the like.

R ³ and R ⁴ are groups having a cyclopentadienyl skeleton, alkyl groups, cycloalkyl groups, aryl groups, aralkyl groups, alkoxy groups, aryloxy groups, trialkylsilyl groups, SO ₃ R, halogen atoms or It is a hydrogen atom.

Specific examples of the metallocene compound in which M is zirconium 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 (methane sulfonate), ethylene bis (indenyl) zirconium bis (p-toluene sulfonate), ethylene bis (indenyl) zirconium Mubis (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 (indenyl)
Zirconium bis (trifluoromethane sulfonate),
Dimethyl silylene bis (4,5,6,7-tetrahydroindenyl) zirconium dichloride, 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 (cyclopenta Dienyl) cyclohexyl zirconium monochloride, bis (cyclopentadienyl) phenyl zirconium monochloride, bis (cyclopentadienyl) benzyl Benzalkonium monochloride,
Bis (cyclopentadienyl) zirconium monochloride monohydride, bis (cyclopentadienyl) methylzirconium monohydride, bis (cyclopentadienyl) dimethylzirconium, bis (cyclopentadienyl) diphenylzirconium, bis (cyclopentadienyl) (Enyl) dibenzyl zirconium, bis (cyclopentadienyl) zirconium methoxy chloride, bis (cyclopentadienyl) zirconium ethoxy chloride, bis (cyclopentadienyl) zirconium bis (methanesulfonato), bis (cyclopentadienyl)
Zirconium bis (p-toluenesulfonato), bis (cyclopentadienyl) zirconium bis (trifluoromethanesulfonato), bis (methylcyclopentadienyl) zirconium dichloride, bis (dimethylcyclopentadienyl) zirconium dichloride, bis ( Dimethylcyclopentadienyl) zirconium ethoxy chloride, bis (dimethylcyclopentadienyl) zirconium bis (trifluoromethanesulfonato), bis (ethylcyclopentadienyl) zirconium dichloride, bis (methylethylcyclopentadienyl) zirconium dichloride, Bis (propylcyclopentadienyl) zirconium dichloride, bis (methylpropylcyclopentadienyl) zirconium dichloride, bis (butylcyclopentadiene) Le) zirconium dichloride, bis (methyl-butylcyclopentadienyl) zirconium dichloride, bis (methyl-butylcyclopentadienyl)
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 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 present invention, as the metallocene compound [A], a compound in which zirconium in the above zirconium compound is replaced by titanium or hafnium can be used.

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, as the metallocene compound [A], a zirconocene compound having a central metal atom of zirconium and having a ligand containing at least two cyclopentadienyl skeletons is preferably used.

Specific examples of the organoaluminum oxy compound [B] used in the present invention include conventionally known aluminoxanes and benzene-insoluble aluminum oxy compounds disclosed in JP-A-2-276807. To be

Such a conventionally known aluminoxane can be produced from the [B-2] organoaluminum compound described below by the following method, for example. (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 solvent or unreacted organoaluminum compound may be removed by distillation from the recovered aluminoxane solution and then redissolved in the solvent. The [B] organoaluminum oxy compound used in the present invention may contain a small amount of a metal component other than aluminum.

The above [B] organoaluminum oxy compound is usually used in an amount of 5 to 1000 mol, preferably 10 to 400 mol, based on 1 mol of the solid metallocene catalyst (calculated as a transition metal atom). Is desirable.

Specific examples of the particulate carrier [C] used in the present invention are SiO ₂ , Al ₂ O ₃ , B ₂ O ₃ and Mg.
O, 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. Of these, SiO ₂ is preferred. These may be used in combination of two or more.

The solid group IVB metallocene catalyst used in the present invention has the above [A] metallocene compound and [B] organoaluminum oxy compound supported on the [C] particulate carrier by a conventionally known method. Formed.

The solid group IVB metallocene catalyst is
The following [B-2] organoaluminum compound may be supported on the [C] particulate carrier together with the [A] metallocene compound and the [B] organoaluminum oxy compound.

When the solid group IVB metallocene catalyst is prepared, the amount of the [A] metallocene compound (calculated as a transition metal atom) is usually 0.001 to 1 per 1 g of the [C] particulate carrier.
The amount of 1.0 millimole, preferably 0.01 to 0.5 millimole, and the amount of the [B] organoaluminum oxy compound is usually 0.1 to 100 millimole, preferably 0.5 to 20 millimole.

The solid metallocene catalyst particles used in the present invention have a particle diameter of 1 to 300 μm, preferably 10 to 300 μm.
It is preferably 100 μm. Further, the solid metallocene catalyst used in the present invention may contain other components useful for olefin polymerization such as an electron donor and a reaction aid, if necessary, in addition to the above catalyst components.

The solid metallocene catalyst used in the present invention may have an olefin prepolymerized on the above solid metallocene catalyst. The solid group IVB metallocene catalyst used in the present invention can (co) polymerize olefins with excellent polymerization activity.

In the present invention, olefin polymerization is carried out using the solid metallocene catalyst as described above.
At the time of polymerization, the following [B-2] organoaluminum compound may be used together with the solid Group IVB metallocene catalyst.

Specific examples of the organoaluminum compound used in the present invention as the [B-2] organoaluminum compound and also in the case of producing the above-mentioned [B] aluminoxane solution include: Trimethyl aluminum, triethyl aluminum, tripropyl aluminum, triisopropyl aluminum, tri n-butyl aluminum, triisobutyl aluminum, tri sec-butyl aluminum, tri tert-butyl aluminum, tripentyl aluminum, trihexyl aluminum, trioctyl aluminum, tridecyl Aluminum, trialkylaluminum such as tricyclohexylaluminum, tricyclooctylaluminum, dimethylaluminum chloride, diethylaluminum chloride, diethylaluminum Dialkyl aluminum halides such as lomid and diisobutyl aluminum chloride, diethyl aluminum hydrides such as diethyl aluminum hydride and diisobutyl aluminum hydride, dialkyl aluminum alkoxides such as dimethyl aluminum methoxide and diethyl aluminum ethoxide, and dialkyl aluminum aryloxides such as diethyl aluminum phenoxide. Is mentioned.

Of these, trialkylaluminum is preferable, and triethylaluminum and triisobutylaluminum 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 and z are positive numbers, and z ≧ 2x). These are two or more kinds. May be a combination of.

The [B-2] organoaluminum compound used in the present invention may contain a small amount of a metal component other than aluminum. When the above [B-2] organoaluminum compound is separately supplied to the reaction system from the solid metallocene catalyst, it is usually 1 to 1000 per 1 mol of the solid metallocene catalyst (transition metal atom conversion). Mole,
It is desirable to use it in an amount of preferably 2 to 300 mol.

When the [B-2] organoaluminium compound is supported on the [C] particulate carrier together with the [A] metallocene compound and the [B] organoaluminum oxy compound, a solid metallocene catalyst (transition metal) is used. It is usually used in an amount of 1 to 200 mol, preferably 2 to 300 mol, based on 1 mol of atom (converted into atoms).

In the present invention, the solid metallocene catalyst as described above may be supplied to the reaction system in a solid powder state,
Further, it may be supplied to the reaction system as a slurry of a hydrocarbon medium. As such a hydrocarbon medium, specifically,
As will be described later, a non-polymerizable hydrocarbon used as a polymerization medium in the present invention can be mentioned, and the same one as this polymerization medium is preferably used.

The olefin gas phase polymerization method according to the present invention polymerizes an olefin in the presence of the above-mentioned olefin polymerization catalyst. Here, the gas phase polymerization method of the olefin according to the present invention will be described in detail with reference to FIG.

The solid group IVB metallocene catalyst 1 as described above is supplied to the fluidized bed reactor 3 through, for example, a line 2. The solid group IVB metallocene catalyst 1 is usually 0.00001 to 1.0 mmol / liter in terms of the transition metal atom in the [A] metallocene compound per liter of the polymerization volume.
It is desirable to use it in an amount of time, preferably 0.0001 to 0.1 mmol / hour.

In the fluidized bed reactor 3, for example, the line 9
Gaseous polymerized olefins and non-polymerizable hydrocarbons supplied from the
The fluidized bed (reaction system) 5 is kept in a fluidized state by being blown from below the fluidized bed reactor 3 through the gas dispersion plate 4 such as a perforated plate, and is provided above the reactor 3. It is decelerated in the deceleration area 3a and circulates in the circulation line 6 again.

The olefin blown into the fluidized bed 5 in which the solid catalyst 1 as described above is kept in a fluidized state undergoes a polymerization reaction here to produce polymer particles (olefin (co) polymer). The produced polymer is continuously withdrawn from the fluidized bed reactor 3 via the line 11. Polymerization
It is also possible to carry out in two or more stages.

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.

Further, cyclopentene, cycloheptene, norbornene, 5-methyl-2-norbornene, tetracyclododecene, 2-methyl 1,4,5,8-dimethano-1,2,3,4,4
Also included are a, 5,8,8a-octahydronaphthalene, styrene, vinylcyclohexane and the like.

In the main polymerization, these olefins are polymerized or copolymerized. Also with olefins,
Polyenes such as butadiene, isoprene, 1,4-hexadiene, dicyclopentadiene and 5-ethylidene-2-norbornene can also be copolymerized.

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 polymerization, a non-polymerizable hydrocarbon that does not polymerize under olefin polymerization conditions or a polymerization inert gas such as nitrogen can coexist, and it is preferable that the non-polymerization hydrocarbon coexists.

In the present invention, it is preferable to use an easily volatile low boiling point non-polymerizable hydrocarbon as the non-polymerizable hydrocarbon. The low boiling point non-polymerizable hydrocarbon is likely to be condensed at a low temperature and can be easily liquefied by a general refrigerant such as water in a condenser (not shown) provided in the circulation line 6 or the like. Is preferred. As such a low boiling point non-polymerizable hydrocarbon, specifically,
There may be mentioned saturated hydrocarbons, and more specifically,
Examples thereof include propane, n-butane, i-butane, n-pentane, i-pentane and cyclopentane. Of these, propane is preferred. These can be used alone or in combination.

During the polymerization, the olefin and the non-polymerizable hydrocarbon are usually supplied in a gaseous state at such a flow rate that the reaction system 5 can be kept in a fluid state. Specifically, when the minimum fluidization rate is U _mf , it is usually about 1.5.
U _mf ~20U _mf, is preferably supplied at a flow rate of about 2U _mf ~10U _mf.

In the present invention, the fluidized bed (reaction system) 5 can be mechanically stirred. Stirring can be performed using various types of stirrers such as an Ikari type stirrer, a screw type stirrer, and a ribbon type stirrer.

In the polymerization, a molecular weight regulator such as hydrogen may be used if necessary, and the fluidized bed reactor 3 may be supplied at any place, for example, from the line 9. The polymerization depends on the olefin to be polymerized and the fluidized state of the fluidized bed (reaction system) 5, but is usually 1 to 10
It is carried out at a polymerization pressure of 0 Kg / cm ² , preferably 2-40 Kg / cm ² .

In the present invention, when carrying out the polymerization using the fluidized bed reactor as described above, at least one compound selected from water, alcohol or ketone is supplied to the fluidized bed reactor 3 together with the olefin. ing. By thus supplying at least one compound selected from water, alcohol or ketone to the fluidized bed reactor, it is possible to reduce the temperature fluctuation of the fluidized bed 5, and this temperature fluctuation is ± 5 ° C. or less, preferably Can be ± 3 ° C. or less.

As the alcohol used in the present invention,
More specifically, methanol, ethanol, isopropanol, n-propanol, tert-butanol, n-hexanol, n-octanol, n-dodecanol, oleyl alcohol, ethylene glycol, propylene glycol, diethylene glycol, methoxyethanol, cyclohexanol, benzyl. Examples thereof include alcohols having about 1 to 18 carbon atoms such as alcohol, isopropylbenzyl alcohol, and phenylethyl alcohol.

Specific examples of ketones include acetone, methyl ethyl ketone, methyl-n-propyl ketone, diethyl ketone, 2-hexanone, 3-hexanone, methyl-t-butyl ketone, di-n-normal propyl ketone,
Examples thereof include diisopropyl ketone, diisobutyl ketone, chloroacetone, acetylacetone and the like.

Of these, alcohols, especially 1 carbon atoms
Alcohols of 10 to 10, especially methanol and ethanol are preferably used. Two or more of these may be used in combination.
At least one compound selected from water, alcohol or ketone as described above may be supplied into the fluidized bed reactor 3 from, for example, the line 10 through the circulation line 6, or the gaseous polymerized olefin or the non-polymerized olefin may be previously supplied. It may be mixed with the active gas and introduced through the line 9.

At least one compound selected from water, alcohol or ketone is 0.03 to 3 with respect to the total amount (gram atom) of the aluminum contained in the organoaluminum oxy compound and the organoaluminum compound as the catalyst component. Mol / 1 gram atom, preferably 0.
1 to 0.3 mol / 1 gram atom, more preferably 0.
1-2 mol / 1 gram atom, especially 0.1-1.5 mol /
It is desirable to provide in an amount of 1 gram atom, more particularly 0.25 to 1.5 mol / 1 gram atom.

The at least one compound selected from water, alcohols and ketones is not particularly limited with respect to 1 mol of the olefin fed to the fluidized bed reactor, but is preferably 0.1 to 400 μmol, preferably 1-30
It is desirable to supply 0 micromol, more preferably 2 to 200 micromol.

Further, at least one compound selected from water, alcohol or ketone is added to 1 gram atom of metal such as Zr contained in the solid metallocene catalyst.
It is desirable to supply in an amount of 1-1000 mol, preferably 5-750 mol, and more preferably 10-500 mol.

At least one compound selected from water, alcohol or ketone is preferably continuously supplied to the fluidized bed reactor 3. In the present invention, if the temperature of the fluidized bed 5 is kept uniform as described above, the (co) polymerization reaction is carried out at 20 to 130 ° C., preferably 5 to 130 ° C.
It is carried out at a temperature of 0 to 120 ° C, more preferably 60 to 100 ° C.

The olefin polymer particles produced by the above-mentioned polymerization are extracted from the line 11, but the unreacted gas and the inert gas such as the non-polymerizable hydrocarbon are discharged in the deceleration zone 3a above the fluidized bed 5. It is decelerated and discharged to the outside of the fluidized bed reactor 3, the heat of polymerization is removed in the heat exchanger 8 and is circulated again to the fluidized bed 5 through the circulation line 6.

According to the present invention as described above, olefin (co) polymer particles having an excellent bulk specific gravity can be obtained in a fluidized bed, and the polymer particles have a small fall time and an angle of repose. Is small and excellent in fluidity, so that the mixed state in the fluidized bed becomes extremely good. Therefore, the temperature distribution in the fluidized bed becomes uniform, and an olefin (co) polymer having excellent particle properties can be stably produced in high yield over a long period of time.

Since the olefin (co) polymer produced in the fluidized bed reactor as described above has excellent fluidity, it is necessary to discharge the olefin (co) polymer from the reactor to the outside of the system. Olefin (co) polymer particles block or form a bridge in an apparatus or an apparatus for drying the olefin (co) polymer, and in poppers used for storing the olefin (co) polymer There is no need to do it, and handling becomes extremely easy.

In the olefin (co) polymer particles obtained as described above, the falling seconds index X of the olefin polymer particles defined as follows is 95 or less, preferably 90 or less, more preferably 85. It is the following.

[0076]

[Equation 3]

(In the formula, to is the number of seconds of dropping of the olefin polymer obtained when neither water, alcohol nor ketone is added to the reactor, and t is at least selected from water, alcohol or ketone in the reactor. It is the number of seconds of dropping of the olefin polymer obtained when one compound is added.) The number of seconds of dropping of the olefin (co) polymer particles in the present specification is the dry flow test according to D-1775. Flow time measured at
The polymer particles of ³ were added to a conical funnel (ASTM D-1895
It is used in the above) and means the time from the funnel mouth having a diameter of 0.95 ± 0.08 cm to the end of the outflow by gravity fall.

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

The olefin (co) polymer obtained according to the present invention usually has an average particle size of 100 to 5000 μm.
m, preferably 300 to 3000 μm, as spherical particles.

The olefin obtained by the present invention
The (co) polymer also depends on the type of olefin polymer.
However, MI (melt index) is usually 0.00
1-1000g / 10 minutes, preferably 0.01-100g
/ 10 minutes is desirable, and the density is usually 0.89 to
0.97 g / cm³, Preferably 0.90 to 0.95 g /
cm ³Is desirable.

The olefin (co) polymer particles have a bulk density of usually 0.30 g / cm ³ or more, preferably 0.40 g / cm ³ or more.

[0082]

INDUSTRIAL APPLICABILITY According to the present invention, in the continuous gas phase polymerization of olefins in the presence of a solid metallocene catalyst using a fluidized bed reactor, the fluidized bed reactor is fed with water, alcohol or ketone. Since at least one selected compound is supplied together with the olefin, an olefin (co) polymer having excellent particle properties such as excellent fluidity in the fluidized bed is generated for a long period of time without generating polymer lumps and the like. It can be produced in a stable and high yield.

[0083]

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 physical properties of the olefin (co) polymers obtained were measured as follows. Bulk density: Measured according to ASTM D-1895.

Falling seconds: measured as described in the description. Angle of repose: Room temperature olefin (co) polymer particles dried by a drier were allowed to flow onto a stainless steel table through a glass funnel as shown in FIG. 2 to deposit the particles in a conical shape. The slope was measured by a protractor and the angle of repose was measured by the injection method.

[0086]

Example 1 [Preparation of catalyst] Silica (S
10 kg of iO ₂ ) was suspended in 154 liters of toluene and then cooled to 0 ° C. To this suspension, 82.0 liters of a toluene solution of methylaminooxane (Al = 1.33 mol / liter) was added dropwise over 1 hour. At this time, the temperature in the system was kept at 0 ° C. Continue to react at 0 ° C for 30 minutes, then raise to 95 ° C over 1.5 hours,
The reaction was carried out at that temperature for 20 hours. Thereafter, the temperature was lowered to 60 ° C., 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.

24.0 liters of a toluene solution of bis (methylbutylcyclopentadienyl) zirconium dichloride (Zr = 27.0 mmol / liter) was added to the suspension thus obtained at 80 ° C. for 30 minutes. Was added dropwise, and the mixture was further reacted at 80 ° C. for 2 hours. Then, the supernatant was removed, and the solid metallocene catalyst containing 5.1 mg of zirconium and 189 mg of aluminum per 1 g of silica was obtained by washing twice with hexane.

The obtained catalyst was a good catalyst having a substantially spherical shape. This catalyst was made into a suspension of propane. [Gas phase polymerization] The diameter of the reaction system 5 as shown in FIG.
Ethylene and 1-hexene are continuously gas-phase copolymerized by a fluidized bed reactor 3 (continuous polymerization apparatus) having a diameter of 0 cm, a height of 180 cm, a fluidized bed volume of 1400 liters, and a maximum diameter of a deceleration zone 3a of 140 cmφ. It was

In the fluidized bed 5 of the fluidized bed reactor 3, the propane suspension of the solid catalyst obtained as described above was added with Zr.
Amount of 1.5 mmol / hour in terms of atoms, and a further amount of 30 mmol / hour of triisobutylaluminum were continuously supplied from line 2 to obtain 135 kg of ethylene.
/ H, 18 kg / h of 1-hexene and 10 l / h of hydrogen at a rate of 10 via line 9.

At the same time, methanol vapor was supplied from line 10 at a constant rate in an amount of 0.55 mol (25 ppm with respect to ethylene) per 1 gram atom of all aluminum.

The polymerization conditions in the gas phase polymerization vessel are as follows: pressure 18 kg /
cm ² G, polymerization temperature of 80 ° C., residence time of 3.0 hours, and the linear velocity of the circulating gas for flow in the gas phase polymerization vessel was maintained at 60 cm / sec.
The gas composition in the gas phase polymerizer was 27.5 mol% of ethylene,
It was 0.91 mol% of 1-hexene and 69.1 mol% of propane.

The produced polyethylene (LLDPE) was
It was continuously withdrawn from line 11 at a rate of 142 kg / hour. The polyethylene obtained as described above is MI
(Melt index) of 1.9 g / 10 min, density of 0.908 g / cm ^3, an average particle size of 830 microns, bulk density was 0.47 g / cm ^3, dropping the number of seconds 5 The polymer particles had a repose angle of 33 ° and were extremely fluid.

Under the conditions as described above, continuous operation was carried out for 300 hours, but the gas-phase polymerization reactor was stable, and the polymer particles were smoothly discharged from the reactor, resulting in extremely stable operation. It was possible.

Further, in order to monitor the temperature in the fluidized bed and the wall surface of the fluidized bed, the height from the dispersion plate is 200 mm, 600 mm, 10
The temperature distribution of the fluidized-bed wall surface was measured continuously at a total of 16 points, with 4 points for each 90 degrees in the inner circumferential direction of 00 mm and 1400 mm, and the temperature fluctuation was 1 to 2 ° C. with respect to the set polymerization temperature. In this state, continuous operation for 300 hours or more was possible.

This indicates that the addition of methanol kept the temperature uniformity in the fluidized bed extremely good, and there was no deterioration of the mixed state due to poor fluidity of the polymer particles, and the flowability was high. It was shown that the polymer particles were sufficiently mixed in the vicinity of the wall surface of the floor, and Comparative Example 1 as shown below was used.
Was extremely effective in terms of long-term stable runnability and handling of polymer particles.

[0096]

Comparative Example 1 Gas phase polymerization was carried out in the same manner as in Example 1 except that methanol vapor was not supplied to the reaction system.

That is, the solid metallocene catalyst obtained in Example 1 was converted into Zr atoms in a fluidized bed reactor 3 (fluidized bed 5) having the same fluidized bed reaction volume of 1400 liters as in Example 1. At an amount of 1.3 mmol / hour,
Further triisobutylaluminum was fed in via line 2 in an amount of 30 mmol / h.

At the same time, ethylene in an amount of 105 kg / hour,
The amount of 1-hexene is 14 kg / hour, and hydrogen is 8 liters /
Feeded through line 9 in the amount of time. The polymerization conditions of the fluidized bed reactor 3 were such that the pressure was 18 kg / cm ² G, the polymerization temperature was 80 ° C., the residence time was 4.0 hours, and the linear velocity of the circulating gas for fluidization in the fluidized bed reactor was maintained at 60 cm / sec.

The gas composition in the fluidized bed reactor was ethylene 2
7.5 mol%, 1-hexene 0.89 mol%, propane 6
Gas phase polymerization was carried out at 9.4 mol%. The polyethylene obtained was continuously withdrawn from line 11 at a rate of 111 kg / hour.

The polyethylene thus obtained is
MI is 2.0g / 10min and density is 0.909g / cm
³ , the average particle size was 820 μm, and the bulk specific gravity was 0.
It was 46 g / cm ³ , the falling time was 8.7 seconds, and the angle of repose of the polymer particles was 41 °. The polyethylene particles had almost the same particle shape as in Example 1, but were inferior in fluidity.

When a long-term continuous operation was attempted, defective polyethylene particles were discharged from the fluidized bed, and the temperature control of the fluidized bed became unstable as described below, and the continuous operation could only be performed for 60 hours.

As in Example 1, the temperature distributions on the fluidized bed and on the fluidized bed wall surface were continuously measured by a thermometer installed for monitoring the temperature in the fluidized bed and on the fluidized bed wall surface. As a result, in the vicinity of the wall surface, the temperature fluctuation is 5 with respect to the set temperature.
It was -10 ° C, and it was confirmed that there was a large variation in the temperature in the fluidized bed.

This indicates that there is a bad mixed state in the vicinity of the wall surface of the fluidized bed due to adhesion of the polymer and the like, and it is presumed that this hinders stable operation. Further, since the discharged polymer particles are inferior in fluidity, a bridge phenomenon occurs due to the aggregation of the polymer particles at the bottom of the polymer particle discharging device and the hopper device, and the discharge is hindered.

[0104]

Example 2 In Example 1, water was used instead of methanol in an amount of 0.28 mol (6.2 ppm with respect to ethylene) per 1 gram atom of total aluminum.
It was continuously fed from 0. The temperature in the fluidized bed 5 was maintained at a temperature fluctuation of 1 to 2 ° C. with respect to the set polymerization temperature during continuous operation for 300 hours.

The polyethylene obtained as described above had an MI (melt index) of 1.8 g / 10 minutes, a density of 0.909 g / cm ³ , and an average particle size of 8
20 μm, bulk specific gravity of 0.47 g / cm ³ , falling seconds of 5.9 seconds, and polymer particles having a repose angle of 35 °.
The spherical particles were excellent in shape and excellent in fluidity.

[0106]

Example 3 In Example 1, the solid catalyst was converted into Zr atoms in an amount of 1.5 mmol / hour, triisobutylaluminum in an amount of 60 mmol / hour, and ethylene in an amount of 135 kg / hour. 1-Hexene was fed at a rate of 18 kg / hr and hydrogen at a rate of 10 liters / hr.

Acetone vapor was used instead of methanol in the amount of 0.07 mol (3.7 ppm with respect to ethylene) per 1 gram atom of total aluminum, and the amount of acetone was increased.
Continuously supplied from. The temperature in the fluidized bed 5 was maintained at a temperature of 1 to 2 ° C. with respect to the set polymerization temperature during the continuous operation period of 300 hours or more.

The polyethylene obtained as described above has an MI (melt index) of 2.1 g / 10 minutes,
Density is 0.909 g / cm ³ , average particle size is 780μ
m, the bulk specific gravity is 0.47 g / cm ³ , the fall time is 6.2 seconds, the angle of repose of the polymer particles is 36 °, and the spherical particles have an excellent flowability and a good shape. Met.

[Brief description of drawings]

FIG. 1 is a diagram showing a gas phase polymerization process of an olefin according to the present invention using a fluidized bed reactor.

FIG. 2 is an illustration of an apparatus for measuring the angle of repose of polymer particles.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Satoru Otani 6-2 1-2 Waki, Waki-cho, Kuga-gun, Yamaguchi Prefecture, Mitsui Petrochemical Industry Co., Ltd. (72) Kenji Doi, Kazu-gun, Kuga-gun, Yamaguchi Prefecture 6-1-2 Waki Kimachi Mitsui Petrochemical Industry Co., Ltd.

Claims (6)

[Claims] 1. When a olefin is continuously fed in the presence of a solid Group IVB metallocene catalyst in a gas phase polymerization using a fluidized bed reactor, the olefin is selected from water, alcohol or ketone. At least one compound is fed to a fluidized bed reactor to polymerize or copolymerize olefins to obtain an olefin polymer having an olefin polymer falling seconds index X of 95 or less as defined below. Gas phase polymerization method of olefin characterized by: (In the formula, to is the number of seconds of dropping of the olefin polymer obtained when neither water, alcohol nor ketone is added to the reactor, and t is at least one kind selected from water, alcohol or ketone in the reactor. It is the fall seconds of the olefin polymer obtained when the compound is added.) 2. A solid group IVB metallocene catalyst comprises a group IVB transition metal compound containing a ligand having a cyclopentadienyl skeleton, an organoaluminum oxy compound, and optionally an organoaluminum compound. The gas phase polymerization method of an olefin according to claim 1. 3. A solid group IVB metallocene catalyst in which a group IVB transition metal compound containing a ligand having a cyclopentadienyl skeleton and an organoaluminum oxy compound are supported on a particulate carrier. The vapor phase polymerization method of an olefin according to claim 2. 4. The addition amount of at least one compound selected from water, alcohol or ketone is based on the total amount (gram atom) of aluminum atoms contained in the organoaluminum oxy compound as a catalyst and the organoaluminum compound. 0.03 to 3 mol / 1 gram atom.
The method for vapor phase polymerization of an olefin according to 1. 5. The falling seconds index X of the olefin polymer is 90.
The method for gas phase polymerization of an olefin according to claim 1, wherein: 6. A gas phase polymerization reaction comprising ethylene and a carbon number of 3 to 1
8. The method for vapor phase polymerization of olefin according to claim 1, wherein the method is a copolymerization with an α-olefin of 8.