JPH07238109A - Method of ethylene polymerization and copolymerization - Google Patents

Abstract

PURPOSE:To provide a polymerization method for efficiently and stably producing a polymer and for enabling long-term stable fluidized-bed vapor-phase polymerization by using a catalyst comprising a combination of a specific solid catalyst component and an organoaluminum compound. CONSTITUTION:A halogenated hydrocarbon having a chlorine-carbon bond is added to a Grignard compound solution containing at least 20vol.% 6C or higher ether, in an amount of at least 0.5mol per mol of the Grignard compound. The mixture is reacted at 60 deg.C or lower to obtain a particulate catalyst support. The support is contacted with an electron donor and a transition metal compound to obtain a solid catalyst component (A). Ethylene or a mixture thereof with an alpha-olefin is prepolymerized in the presence of a catalyst comprising the component (A) and an organoaluminum compound (B) to obtain a prepolymer having a weight-average mol.wt. of 6X10<5> in an amount of 0.01-0.9g per g of the component (A). Gaseous ethylene is polymerized alone or with an a-olefin in the presence of the prepolymer at 50-110 deg.C in a fluidized-bed polymerizer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for polymerizing ethylene or copolymerizing ethylene and .alpha.-olefin.

[0002]

2. Description of the Related Art Polymerization of ethylene by Ziegler-Natta type catalyst, or ethylene and α
-Copolymerization with olefin is carried out by a polymerization method such as solution polymerization, bulk polymerization, slurry polymerization, gas phase polymerization and the like. In recent years, a fluidized bed polymerization reaction that enhances the catalytic activity and does not require a step of separating a catalyst residue from the produced copolymer has become widespread, and for the purpose of preparing catalyst particles having high catalyst activation and good fluidity. In addition, there have been proposed many highly active catalysts in which a transition metal component such as titanium or vanadium is supported on an inorganic solid or an inorganic solid having a specific particle size.

It is known that in fluidized bed polymerization, the temperature inside the fluidized bed is destabilized by the local accumulation of polymerization heat, and the fluidized state is easily destroyed by the formation of a large lump polymer. For example, JP-A-59-89706, 59-22907, and 61-
In No. 123606, when a polymer is produced in a fluidized bed polymerization reactor, a granular catalyst in which a transition metal component is supported on an inorganic carrier such as magnesium chloride or silica is polymerized while maintaining a fluid state by an upward flow of a monomer gas. A method of doing is disclosed.

However, the inorganic carrier such as silica is
There is a problem that it is easily broken into fine powder during the polymerization, which makes the stable polymerization reaction difficult. Therefore, for example, Japanese Examined Patent Publication Nos. 52-40350, 52-45749, and 60-53044
In JP-A-59-30806, a prepolymer is prepared in advance, and the prepolymer is used in a fluidized bed polymerization reactor to improve the polymer production amount per transition metal weight and A method for preventing rapid heat generation and particle agglomeration in the solid catalyst portion immediately after being introduced into the bed polymerization reactor is disclosed. In this case, the particle shape of the polymer is likely to be a replica of the particle shape of the catalyst, and in order to efficiently and stably produce the polymer, particles of the catalyst solid and the prepolymer used in the fluidized bed polymerization reaction are used. It is important to control the shape, i.e. to form the catalyst solids and prepolymers that remain spherical.

[0005]

DISCLOSURE OF THE INVENTION The present invention improves the problems of the process for producing a polymer of ethylene or a copolymer of ethylene and α-olefin, and in particular, it is produced by fluidized bed gas phase polymerization. In some cases, it is intended to provide a long-term stable polymerization reaction method.

[0006]

DISCLOSURE OF THE INVENTION The present invention provides a solid catalyst component containing (A) magnesium, a transition metal and halogen as essential components, and (B) an organoaluminum compound component in the presence of a catalyst containing ethylene and / or Alternatively, in the method of contacting with α-olefin to form a prepolymer and polymerizing ethylene in the presence of the prepolymer, or copolymerizing ethylene and α-olefin, the amount of the prepolymer is Provided is 0.01 to 0.9 g per 1 g of a solid catalyst, and a method for polymerizing ethylene and copolymerizing ethylene with an α-olefin, characterized in that the weight average molecular weight of the prepolymer is 6 × 10 ⁵ or more. It is a thing.

Hereinafter, each component used in the preparation of the catalyst of the present invention and its conditions will be described in detail. In the present invention, the preparation and polymerization of the catalyst component are all carried out under an atmosphere of an inert gas such as nitrogen or argon. Further, it is desirable that the raw material for preparing the catalyst component is substantially anhydrous.

The solid catalyst component (A) in the present invention contains magnesium, transition metal and halogen as essential components. Examples of the transition metal include titanium, vanadium, zirconium, hafnium and the like.

The method for producing the solid catalyst component is not particularly limited, and examples thereof include JP-A-56-55405 and JP-A-56-459.
09 publication, 56-163102 publication, 57-115408 publication,
58-83006, 59-22907, 59-22908, 62-232405, 62-297304 and 60-.
The method proposed in 32805 can be adopted. For example, (1) magnesium compounds such as magnesium chloride,
A method of co-milling an electron donor and titanium tetrachloride, (2)
Dissolve the magnesium compound and electron donor in an organic solvent,
Examples include a method of adding titanium tetrachloride to this solution to precipitate a solid, and (3) a method of supporting a titanium compound on a carrier obtained by the reaction of an organomagnesium compound and an organic halide.

In the present invention, a catalyst carrier produced by reacting a Grignard compound solution with a halogenated hydrocarbon compound is used as an electron donor and at least one transition metal compound selected from titanium, zirconium, hafnium and vanadium. The manufacturing method in which the contact treatment is performed can be suitably used.

A particulate solid is formed by the reaction of the Grignard compound solution with the halogenated hydrocarbon compound. More preferably, a spherical solid carrier as a carrier is obtained by adding a chlorinated hydrocarbon compound to a solution of a Grignard compound containing 20% by volume or more of an ether having a total carbon number of 6 or more and reacting at 60 ° C. or less.

The Grignard compound is represented by the formula R ¹ MgX ¹ (wherein R ¹ represents a hydrocarbon group having 1 to 20 carbon atoms and X ¹ represents a halogen atom). Alkylmagnesium chloride in which X ¹ is a chlorine atom is preferably used, and specific examples thereof include methylmagnesium chloride, ethylmagnesium chloride, n-butylmagnesium chloride and n-hexylmagnesium chloride.

Generally, the Grignard compound can be prepared as an ether solution or as a solution in a hydrocarbon solvent containing a minimum amount of ether. In particular, it is preferable that the total amount of ether having 6 or more carbon atoms is 20% by volume or more in the Grignard compound. Specific examples of the ether having 6 or more carbon atoms include dipropyl ether, diisopropyl ether, dibutyl ether,
Examples thereof include diisobutyl ether, diisoamyl ether and dihexyl ether.

The halogenated hydrocarbon compound to be reacted with the solution in which the Grignard compound of the present invention is dissolved is
Particularly preferred are saturated or unsaturated hydrocarbon compounds containing a chlorine-carbon bond. Specific examples thereof include chloroform, methylene chloride, methyl chloride, ethyl chloride, propyl chloride, isopropyl chloride, butyl chloride, sec-butyl chloride,
Examples include tert-butyl chloride, hexyl chloride, chlorobenzene, dichlorobenzene, trichlorobenzene and benzyl chloride. Besides the above compounds,
An ether compound containing a halogen / carbon bond can also be used, and specific examples thereof include bis-2-chloroethyl ether and 2-chloroethyl methyl ether.

The reaction method is not particularly limited, but a method of adding a halogenated hydrocarbon compound to a container charged with the Grignard compound solution can be used.
It is preferable to keep the reaction temperature at 60 ° C. or lower, particularly 50
C. or less is preferable. In this reaction, temperature, time,
The addition rate of the halogenated hydrocarbon compound, the stirring rate of the reaction solution, and the like affect the shape, particle size, and particle size distribution of the carrier particles formed. A preferred reaction method is to gradually add the halogenated hydrocarbon compound to the Grignard compound solution while maintaining the temperature at 60 ° C or lower, and then stir the reaction solution at a reaction temperature of 60 ° C, more preferably within a range not exceeding 50 ° C. While gradually raising the temperature, the solid particles are precipitated. By this method, the shape, particle size, and particle size distribution of particles can be controlled. The proportion of the halogenated hydrocarbon compound used for the reaction between the Grignard compound solution and the halogenated hydrocarbon compound is preferably 0.5 mol or more, and particularly preferably 1 mol or more per 1 mol of the Grignard compound.

In the present invention, when the Grignard compound solution and the halogenated hydrocarbon compound are reacted with each other, the organoaluminum compound can coexist in advance with the Grignard compound solution as long as it does not come into contact with the Grignard compound to precipitate a solid at room temperature. Specific examples of the organoaluminum compound include trimethylaluminum, triethylaluminum, triisobutylaluminum, trialkylaluminum such as tri-n-hexylaluminum, methylaluminum-t-butoxide, ethylaluminum-
Examples thereof include alkylaluminum dialkoxides and dialkylaluminum alkoxides such as t-butoxide, ethylaluminum isopropoxide, isobutylaluminum-t-butoxide and isobutylaluminum isopropoxide. The above-mentioned aluminum alkoxide compound can be easily prepared by reacting a desired molar ratio of trialkylaluminum with an alcohol.

The catalyst support may be treated with a transition metal compound, or with a suitable conventionally known electron donor and transition metal compound.
A solid catalyst can be produced. The order of contact treatment of the electron donor and the transition metal compound with the carrier is not particularly limited, but a method in which the carrier and the electron donor are first contacted and then the transition metal compound is subsequently contacted is preferable.

The electron donor used in the present invention includes organic acid esters, inorganic acid esters, acid halides, ethers,
Acid amides, N, N-dialkyl acid amides, amines, nitriles, acid anhydrides, silicate compounds, ketones, alcohols, aldehydes, carboxylic acids, isocyanates and the like can be used. A silicate compound is particularly preferable.

Specific examples of the silicate compound include tetramethoxysilane, tetraethoxysilane and tetra-n-
Propoxysilane, tetra-n-butoxysilane, tetra-isopentoxysilane, tetra-n-hexoxysilane, methyltrimethoxysilane, methyltriethoxysilane, methyltri-n-butoxysilane, methyltriisopentoxysilane, methyltri-n -Hexoxysilane,
Ethyltriethoxysilane, ethyltriisopropoxysilane, ethyltriisopentoxysilane, n-butyltriethoxysilane, isobutyltriethoxysilane, isopentyltriethoxysilane, isopentyltri-n-
Butoxysilane, dimethyldiethoxysilane, dimethyldi-n-butoxysilane, dimethyldiisopentoxysilane, diethyldiethoxysilane, diethyldiisopentoxysilane, diisobutyldiisopentoxysilane, di
-n-butyldiethoxysilane, diisobutyldiisopentoxysilane, trimethylmethoxysilane, trimethylethoxysilane, trimethylisobutoxysilane, triethylisopropoxysilane, tri-n-propylethoxysilane, tri-n-butylethoxysilane, tri Isopentylethoxysilane, phenyltriethoxysilane,
Phenyltriisobutoxysilane, phenyltriisopentoxysilane, diphenyldiethoxysilane, diphenyldiisopentoxysilane, diphenyldioctoxysilane, triphenylmethoxysilane, triphenylethoxysilane, triphenylisopentoxysilane, benzyltri Ethoxysilane, benzyltributoxysilane, dibenzyldiethoxysilane, cyclopentyltrimethoxysilane, 2-methylcyclopentyltrimethoxysilane, 2,3-dimethylcyclopentyltrimethoxysilane, cyclopentyltriethoxysilane, tricyclopentylethoxysilane and the like. . Two or more kinds of these silicate compounds may be used in combination. Above all,
Methyltriethoxysilane is preferably used.

The transition metal compound has the formula MX ² _p (O
R ⁴ ) _pq R ⁵ _pqr (where M is titanium, zirconium,
Indicates hafnium or vanadium, X ² is a halogen atom, R ⁴ and R ⁵ are hydrocarbon groups having 1 to 20 carbon atoms, p is the maximum valence of the metal, and 0 <q <p, 0 <q + r <p. ), A transition metal halide, a hydrocarbyl oxyhalide, a hydrocarbyloxy halide, a hydrocarbyloxyhydrocarbyl halide, a hydrocarbyl halide, a hydrocarbyloxyhydrocarbyl halide and the like. In the above formula
R'includes a cycloalkadiene with π coordination,
Further, a transition metal compound, which is usually called metallocene, having two cycloalkadiene ligands independently / or by bridging can be employed.

A titanium compound can be preferably used as the transition metal compound. Specific examples thereof include methoxytrichlorotitanium, dimethoxydichlorotitanium, trimethoxychlorotitanium, ethoxytrichlorotitanium,
Diethoxydichlorotitanium, propoxytrichlorotitanium, dipropoxydichlorotitanium, butoxytrichlorotitanium, dibutoxydichlorotitanium, phenoxytrichlorotitanium, diphenoxydichlorotitanium, methoxytribromotitanium, phenoxytribromotitanium, methoxytriiodotitanium. , Phenoxytriiodotitanium, tetrachlorotitanium, tetrabromotitanium, tetraiodotitanium, tetramethoxytitanium, tetraethoxytitanium, tetrapropoxytitanium and the like. Two or more kinds of these titanium compounds may be used in combination. Among them, tetrachlortitanium, methoxytrichlortitanium,
Dimethoxydichlorotitanium, ethoxytrichlorotitanium, diethoxydichlorotitanium, propoxytrichlorotitanium, dipropoxydichlorotitanium, butoxytrichlorotitanium and dibutoxydichlorotitanium are particularly preferably used.

The contact treatment temperature with the transition metal compound is usually 10 to 100 ° C., preferably 20 to 60 ° C., and particularly preferably 25.
It is preferable that the treatment is performed at ˜45 ° C. for 10 minutes to 10 hours. After the contact treatment, it is preferable to obtain a solid catalyst by repeating filtration separation of the solid from the organic solvent and washing with the organic solvent.

In the present invention, a catalyst component containing magnesium, a transition metal and halogen as essential components can be supported on a porous inorganic oxide for use. Examples of the inorganic oxide include silica, alumina, magnesia, titania, zirconia, and calcia. Especially, silica is preferable.

The average particle size of the inorganic oxide is usually 5
.About.150 .mu.m, preferably ³⁰ to 50 .mu.m, making the resulting polymer particle size suitable for providing a bulk density of 0.36 to 0.42 kg / m.sup.3. The inorganic oxide is preferably porous fine particles having a specific surface area of 50 to 800 m ² / g, for example 100
It can be used after heat treatment at up to 800 ° C.

As a method for producing a solid catalyst component supported on a porous inorganic oxide, for example, (1) a porous inorganic oxide is contact-treated with a silicon halide compound in advance, and a magnesium compound, an organoaluminum compound and a titanium compound are prepared. A method of contact treatment with (JP-A-1-292010),
(2) A method in which a porous inorganic oxide is preliminarily contact-treated with an organometallic compound and then contact-treated with a magnesium compound, an organoaluminum compound and a titanium compound dissolved in an electron donor (JP-A-1-287107), ( 3) A method of dissolving a titanium compound and a magnesium compound in an electron donor and impregnating this with a porous inorganic oxide (Japanese Patent Laid-Open No. 57-446).
No. 11), (4) a method of contact-treating a porous inorganic oxide with an organometallic compound in advance, and a contact treatment with a halogenated silicon compound and a titanium compound (JP-A-61-151211), (5) Porosity Of contacting a porous inorganic oxide with an alumoxane compound and a zirconium compound (Japanese Patent Laid-Open Publication No. 6-58242)
1-296008, JP-A-1-98608), (6) Method of contacting a porous inorganic oxide with an organoaluminum compound, a silicon halide compound and a vanadium compound (JP-A-61-151206), etc. The method of is mentioned.

Examples of the organoaluminum compound component (B) include trialkylaluminum, dialkylhalogenoaluminum, sesquialkylhalogenoaluminum, alkenylaluminum, dialkylhydroaluminum and sesquialkylhydroaluminum.

Specific examples of these organoaluminum compounds include trialkylaluminums such as trimethylaluminum, triethylaluminum, triisobutylaluminum, tri-n-hexylaluminum, dimethylaluminum chloride, diethylaluminum chloride, dibutylaluminum chloride and diethylaluminum. Dialkylhalogenoaluminum such as bromide, ethylaluminum sesquichloride, sesquialkylhalogenoaluminum such as ethylaluminum sesquibromide, ethylaluminum dichloride, propylaluminum dichloride, butylaluminum dichloride, ethylaluminum dibromide, propylaluminum dibromide, butylaluminum dibromide, Diethyl aluminum Hydride, dibutyl aluminum hydride, ethyl aluminum dihydride, propyl aluminum dihydride, butylaluminum dihydride,
Ethyl aluminum ethoxy chloride, ethyl aluminum butoxycyclolide, ethyl aluminum ethoxy bromide and the like can be mentioned.

It is also possible to use isopropenylaluminum obtained by the reaction of diisobutylaluminum hydride and isoprene. Further, for example, an alkylalumoxane obtained by a reaction of trialkylaluminum with water dispersed in a solvent or a reaction of water of crystallization of an inorganic compound can be used. General formula, a linear or cyclic polymer represented by (-Al (R) O-) _n (R is a hydrocarbon group having 1 to 10 carbon atoms, and is partially substituted with a halogen atom and / or an RO group. N is a degree of polymerization and is 5 or more, preferably 10 or more), and specific examples thereof are methylalumoxane, ethylalumoxane and isobutyl in which R 1 is a methyl, ethyl or isobutyl group, respectively. Examples include ethyl alumoxane.

Of these, trialkylaluminums such as triethylaluminum and triisobutylaluminum are preferably used.

In the present invention, the catalyst comprising the components (A) and (B) is ethylene, or ethylene and α
The prepolymerization is carried out with a mixture with olefins.

Specific examples of the α-olefin include propylene, butene-1, pentene-1, 4-methylpentene-1, hexene-1, octene-1 and the like having 3 to 3 carbon atoms.
There are 10 α-olefins. Among them, butene-
1,4-methylpentene-1, hexene-1, and octene-1 can be preferably used.

As the polymerization solvent for the prepolymerization, an inert organic solvent may be used, or a liquid α-olefin itself may be used.

As preferred conditions for producing the prepolymer, the polymerization pressure is usually atmospheric pressure to 10 kg / cm ² , and the polymerization temperature is 100 ° C. or lower, usually 20 to 70 ° C. The polymerization time is
Usually, it is 30 minutes to 15 hours, preferably 2 to 10 hours.

The amount of the organoaluminum compound component (B) used in the prepolymerization is usually 0.1 to 1000 mol, preferably 0.5 to 200 mol, per 1 gram atom of the transition metal in the solid catalyst component (A).

The prepolymer can be subjected to the main polymerization after the polymerization solvent is evaporated, for example, with an inert gas, dried and removed to obtain a powder. Alternatively, immediately after the preliminary polymerization, ethylene polymerization or copolymerization of ethylene and α-olefin may be performed as main polymerization.

In the prepolymerization, the amount of the prepolymer is 0.01 to 0.9 g per 1 g of the solid catalyst, more preferably 0.1 to 0.9 g.
0.5 g, and the weight average molecular weight of the prepolymer is
The conditions are such that a prepolymer having a size of 6 × 10 ⁵ or more, and more preferably 1 × 10 ⁶ or more can be obtained.

If the prepolymerization is insufficient and the amount of the prepolymer is smaller than the above range, the strength of the prepolymer is insufficient and it is difficult to maintain the catalyst shape during the polymerization.

If the prepolymerization proceeds too much and exceeds the above range, the catalyst particles tend to aggregate. Further, the particle size of the prepolymer becomes too large, and further, the bulk density of the product polymer is lowered, which causes a large change in the physical properties, which is not preferable. It also becomes a source of gel in the product.

When the weight average molecular weight of the obtained prepolymer is smaller than the above value, the prepolymer is liable to be broken into fine powder during the polymerization, which makes it difficult to carry out a stable polymerization reaction in a fluidized bed. The ratio of the amount of the prepolymer to the total polymer is preferably 1.0 to 0.0001% by weight.

As the conditions for producing the desired prepolymer, the polymerization pressure is usually atmospheric pressure to 10 kg / cm ² , and the polymerization temperature is 100 ° C. or lower, usually 20 to 70 ° C. The polymerization time is usually 30 minutes to 15 hours, preferably 2 to 10 hours.

The weight average molecular weight of the prepolymer can be adjusted by coexisting with a molecular weight modifier such as hydrogen. Next, the prepolymer produced as described above has a narrow particle size distribution and a small proportion of fine particles.

When an excess amount of the organoaluminum compound component (B) is used in the prepolymerization, the component (B) is used in the main polymerization.
The polymer can be produced without additional use of.

The prepolymer produced as described above may be used for the main polymerization after further second-stage prepolymerization, if necessary. In the second stage prepolymerization in this case, the polymerization method and the polymerization conditions are the same as those in the above first stage prepolymerization, but the polymerization amount and the molecular weight of the polymer are not particularly limited.

The main polymerization reaction can be carried out in the same manner as the polymerization reaction of α-olefin with a conventional Ziegler-Natta type catalyst. Examples of the gas phase polymerization reaction include a fluidized bed polymerization method and a stirring polymerization method.

Particularly when the fluidized bed polymerization method is used, gaseous ethylene is polymerized in the fluidized bed polymerization reactor in the presence of the prepolymer produced as described above, or ethylene and α-olefin are mixed. Are copolymerized. As the α-olefin in the main polymerization, the same as or different from those used in the preparation of the prepolymer can be used. In the main polymerization, the heat of polymerization is removed by the monomer gas while the prepolymer is fluidized by the monomer gas,
Usually, the polymerization is carried out at 50 to 110 ° C.

When the polymerization reaction is carried out in a liquid phase, an inert organic solvent may be used as a polymerization solvent, and liquid α-
The olefin itself may be used. Examples of the inert organic solvent include hydrocarbon solvents such as heptane, hexane, toluene and xylene.

The catalyst concentration in the polymerization solvent is not particularly limited, but in general, the solid catalyst component (A) is 0.001 to 1 milligram atom in terms of transition metal per 1 L of the polymerization solvent, and the organoaluminum compound is used. Ingredient (B)
Is about 0.01 to 100 mmol.

The polymerization reaction is carried out in a state where water and oxygen are substantially removed. The polymerization temperature is usually 30 to 100 ° C., and the polymerization pressure is usually 1 to 80 kg / cm ² .

The prepolymer of the present invention has a moderate initial activity, so that abrupt local polymerization exotherm does not cause aggregation of the polymer. On the other hand, the polymerization activity lasts for a long time, so that the fluidized bed polymerization reactor is used. Since the polymer obtained in (1) has a large amount of polymer produced per solid catalyst, it can be pelletized without deashing after the polymerization.

[0050]

INDUSTRIAL APPLICABILITY In the present invention, the prepolymer is used as a catalyst particularly when the gaseous ethylene is polymerized or the gaseous ethylene and α-olefin are copolymerized in the fluidized bed polymerization reactor. As a result, good fluidity of the polymer can be maintained in the main polymerization, and the heat of polymerization can be easily controlled.

Therefore, the final polymer produced has features such as a relatively large particle size, a large bulk density, and no formation of fine particles, and is easy to handle. The prepolymer of the present invention is not accompanied by a rapid heat generation in the initial stage of polymerization,
Moreover, since the polymerization activity is high, deashing treatment etc. is not required,
Further, also in the copolymerization of ethylene and α-olefin, the copolymerizability of α-olefin is excellent.

[0052]

EXAMPLES Examples of the present invention will be described below. The Ti content of the solid catalyst component was measured by a colorimetric method. The Mg content and Al content of the solid catalyst component are UOP- manufactured by Kyoto Koken Co., Ltd.
1 Measured by MARK II type ICP. The weight average molecular weight of the prepolymer was measured by GPC (150CV type) manufactured by Waters.

The bulk density of the polymer was determined by filling the polymer in a graduated cylinder using a vibrator to obtain a volume of 10 ml.
It was calculated by the weight of the polymer. Polymer density was measured by a density gradient tube. The melt index (MI) of a polymer is the melt index of the polymer as measured by ASTM D-1238 at 190 ° C. under a load of 2.16 kg.
The melting point of the polymer is the temperature of the maximum absorption peak in the high temperature part in the DSC measurement. The measurement conditions are 160 ° C / min for the sample.
After heating up to ℃, melting and holding for 10 minutes, 5 ℃ /
The temperature is decreased in minutes, and the temperature is increased again at 10 ° C / minute.

Example 1 (Synthesis of carrier solid) A 1 L glass reactor equipped with a mechanical stirring system and a double jacket and prefilled with nitrogen was charged with 262 mL of toluene and 12 mmol of triethylaluminum and kept at 26 ° C. While adding 12 mmol of tert-butyl alcohol. To this mixture was added 40.2 mL of a diisoamyl ether solution containing 60 mmol of n-butylmagnesium chloride. 66 mmol of tert-butyl chloride was added dropwise over 5 minutes while raising the temperature to 40 ° C. Furthermore, the reaction was carried out for 5 hours while maintaining the temperature at 40 ° C.

The produced carrier solid was filtered off, and 50 mL of toluene was added.
At 40 ℃ after washing once with 50 mL of n-heptane for 3 times.
And dried under reduced pressure for 2 hours. The obtained carrier solid was spherical particles having a relatively narrow distribution with a particle size (radius) of 30 to 40 μm.

(Synthesis of solid catalyst component) 5 g of the above carrier solid
Is slurried in 75 mL of toluene, and first, 75 mmol of methyltriethoxysilane as an electron donor is added to 40 mL.
The mixture was stirred at 0 ° C for 30 minutes, 100 mmol of tetrachlorotitanium was added, and the mixture was stirred at 40 ° C for 60 minutes. The solid was then filtered off, washed 3 times with 50 mL toluene and once with 50 ml heptane and dried. The obtained spherical solid had a Ti content of 0.97%, an Al content of 0.61%, and an Mg content of 15.7%.

(Synthesis of Prepolymer) 700 mL of n-heptane was added to a 2 L autoclave made of stainless steel filled with nitrogen gas.
Was charged, 0.5 mmol of triethylaluminum and 20 g of the solid catalyst obtained in Example 2 were added, and 2.0 k of ethylene was added.
Introduced g / cm ² . Solvent temperature in autoclave 70 ℃
In addition, 21.7 mmol of triethylaluminum was added and polymerized until 1 g of ethylene was consumed per 1 mmol of Ti. Immediately, ethylene was depressurized, the solvent was removed under a nitrogen atmosphere, and 24.5 g (solid catalyst
0.2 g / g) was recovered. The weight average molecular weight of the prepolymer was 1 × 10 ⁶ .

(Second Stage Prepolymerization) The above prepolymer is used.
In addition, 1.0 kg / cm of hydrogen²And ethylene 2.0 kg / cm
²Consumption of 50 g of ethylene per 1 mmol of Ti under
Polymerized until Release the pressure and remove the solvent under a nitrogen atmosphere.
153g as a prepolymer (6.7g per 1g of solid catalyst)
Was recovered. The weight average molecular weight of the prepolymer is 2 × 10^Fiveso
there were.

(Polymerization of Ethylene) 660 g of polyethylene powder stored under nitrogen was introduced into a fluidized bed reactor having a diameter of 10 cm. After sufficiently removing water from the reactor,
Heat to 80 ° C, then change the gas composition to ethylene 5.81at
m, 1-butene 1.93atm, hydrogen 1.28atm, and nitrogen 1.28a
tm and passed upward through the bed at a flow rate of 25 cm / sec. 1.07 g of the prepolymer prepared in Example 4 was introduced into a fluidized bed reactor and the temperature in the bed was kept at 80 ° C for 3 hours. The polyethylene powder thus produced weighed 478 g and had a bulk density of 0.34, a density of 0.9149, an MI of 3.54,
The melting point was 122.9 ° C.

Example 2 In the synthesis of the prepolymer of Example 1, 27.8 g of the solid catalyst of Example 1 and 44 mmol of triethylaluminum,
32.6 g (0.17 g per 1 g of solid catalyst) was recovered as a prepolymer in the same manner except that the ethylene pressure was 0.8 kg / cm ² . The weight average molecular weight of the prepolymer was 6 × 10 ⁵ .

Further, as the second stage prepolymerization, 1.0 kg of hydrogen /
Polymerization was carried out under the conditions of cm ² and 2.0 kg / cm ² of ethylene until 50 g of ethylene was consumed per 1 mmol of Ti. Release the pressure, remove the solvent under a nitrogen atmosphere, and use as a prepolymer 1
70 g (5.1 g per 1 g of solid catalyst) were recovered. The weight average molecular weight of the prepolymer was 2 × 10 ⁵ .

(Polymerization of Ethylene) 690 g of polyethylene powder stored under nitrogen was introduced into a fluidized bed reactor having a diameter of 10 cm. After sufficiently removing water from the reactor,
Heat to 80 ℃, then change the gas composition to ethylene 5.64at
m, 1-butene 1.88 atm, hydrogen 1.41 atm, and nitrogen 7.55a
tm and passed upward through the bed at a flow rate of 25 cm / sec. 0.64 g of the above prepolymer was introduced into a fluidized bed reactor and the temperature in the bed was kept at 80 ° C. for 3 hours. The polyethylene powder thus produced weighed 478 g and had a bulk density of 0.20, a density of 0.9157, an MI of 2.88 and a melting point of 122.4.
It was ℃.

Comparative Example 1 (Synthesis of Prepolymer-5) 700 mL of n-heptane was charged into a 2 L autoclave made of Stellence filled with nitrogen gas, 31 mmol of triethylaluminum and Example 1
27.8 g of the solid catalyst obtained in step 2 was added, and 0.8 kg / cm ^{2 of} ethylene was added.
And 1.0 kg / cm ² of hydrogen were introduced. The temperature of the solvent in the autoclave was raised to 70 ° C and polymerization was carried out until 40 g of ethylene per 1 mmol of Ti was consumed.
0 g (5.5 g per 1 g of solid catalyst) was recovered. The weight average molecular weight of the prepolymer was 2.6 × 10 ⁵ .

(Polymerization of Ethylene) 550 g of polyethylene powder stored under nitrogen was introduced into a fluidized bed reactor having a diameter of 10 cm. After sufficiently removing water from the reactor,
Heat to 80 ℃, then change the gas composition to ethylene 5.60at
m, 1-butene 1.86atm, hydrogen 1.53atm, and nitrogen 7.49a
tm and passed upward through the bed at a flow rate of 25 cm / sec. 0.52 g of the above prepolymer was introduced into a fluidized bed reactor and the temperature in the bed was kept at 80 ° C. for 3 hours. The polyethylene powder thus produced weighed 221 g and had a bulk density of 0.16, a density of 0.9199, an MI of 1.65 and a melting point of 122.9.
It was ℃.

[Brief description of drawings]

FIG. 1 is a flow chart of a preparation process and a polymerization method of a solid catalyst component used for polymerization according to the present invention.

Continuation of the front page (72) Inventor Toshifumi Fukunaga 8-1 Goi Minamikaigan, Ichihara, Chiba Ube Industries Ltd. Chiba Research Institute

Claims (1)

[Claims] 1. Contact of ethylene and / or α-olefin in the presence of a catalyst comprising (A) a solid catalyst component containing magnesium, a transition metal and halogen as essential components and (B) an organoaluminum compound component. To form a prepolymer and polymerize ethylene in the presence of the prepolymer, or copolymerize ethylene with an α-olefin, the amount of the prepolymer is 0.01 per 1 g of the solid catalyst.
~ 0.9 g, and the prepolymer has a weight average molecular weight of 6
A method of polymerizing ethylene and a copolymerization of ethylene and an α-olefin, characterized in that x10 ⁵ or more.