JPH07157525A - Production of propylene block copolymer - Google Patents

Abstract

PURPOSE:To obtain the subject excellent copolymer high in both rigidity and impact strength by polymerization between propylene and an alpha-olefin in the presence of a catalyst comprising a titanium-contg. solid catalytic component, organosluminum compound component and electron-donating compound followed by vapor phase copolymerization with another alpha-olefin. CONSTITUTION:In the presence of a catalyst comprising (A) a titanium-contg. solid catalytic component (e.g. a carrying-type highly active catalyst, prepared e.g. by cogrinding a magnesium compound such as magnesium chloride, electron donor and halotitanium compound such as TiCl4), (B) an organoaluminum compound component (e.g. a haloalkylaluminum) and (C) an electron-donating compound (e.g. t-butylmethyl dimethoxysilane), (1) a polymerization of propylene or its copolymerization with another alpha-olefin is conducted and (2) without deactivating the catalytic system, a haloether is added to the reactional system to carry out a vapor phase copolymerization of the propylene with another alpha-olefin, thus obtaining the objective copolymer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a propylene block copolymer having high rigidity and excellent impact strength.

[0002]

2. Description of the Related Art Homopolymerization of propylene or copolymerization of propylene with other α-olefins in the preceding stage to produce a stereoregular (co) polymer of propylene, and then the presence of the (co) polymer It is known to produce a propylene block copolymer by vapor-phase copolymerizing propylene and another α-olefin in the lower and latter stages. The product obtained here is a homogenous mixture of the polymers or copolymers produced in each stage, but is generally called a propylene block copolymer.

This method is extremely useful for maintaining the balance between the rigidity and the impact resistance of the propylene block copolymer, but it is composed of a first step of polymerizing in liquid propylene and a second step of copolymerizing step. Therefore, the activity sustainability of the latter-stage polymerization catalyst is the most important requirement. Each of the first-stage and second-stage polymerization processes may use a plurality of polymerization vessels.

Further, a major problem in the latter gas phase polymerization method is that the tackiness increases and the fluidity deteriorates, causing clogging and scaling of the reactor and lines, or
Since the monomer concentration is low, the productivity per unit time may be remarkably reduced, and improvement of these problems has been earnestly desired.

In stereoregular polymerization of propylene, the polymerization activity of what is usually called a supported catalyst is
Although it shows high activity in the early stage, it has poor activity persistence,
When producing a propylene block copolymer, the copolymerization activity in the latter stage was low, and it was difficult to produce the copolymer in high yield. The following means can be considered as a method of increasing the ratio of the copolymer in the latter stage.

(1) A method of shortening the polymerization time in the first stage to suppress the polymerization activity of the polymerization catalyst in the first stage and relatively increase the amount of the copolymer in the second stage. However, in this method, the catalyst efficiency as a whole is lowered and the catalyst residue in the copolymer is increased, which is a problem in terms of product quality.

(2) A method of relatively increasing the amount of copolymer in the latter stage by lowering the polymerization temperature in the former stage and suppressing deactivation of the polymerization catalyst. However, with this method,
Since the catalyst efficiency as a whole is lowered and the stereoregularity of the copolymer is lowered, the rigidity of the product is lowered and the amount of catalyst residue in the product is increased.

(3) A method of increasing the copolymerization amount in the latter stage by increasing the copolymerization temperature in the latter stage. However, in this method, although it is possible to increase the amount of the copolymer in the latter stage, the improvement rate of the impact resistance is small because the molecular weight of the produced rubber component is low, and the copolymers are It has the drawback of sticking easily.

(4) A method of increasing the copolymerization amount in the latter stage by increasing the copolymerization pressure in the latter stage. However, in this method, there is a problem in that there are restrictions on the apparatus, and if the equipment is used to increase the pressure resistance, the equipment cost will increase, and eventually the cost of the product will increase.

(5) A method of increasing the copolymerization time in the latter stage. However, in this method, since the polymerization rate in the latter stage is lower than the polymerization rate in the former stage, it is not desirable to prolong the copolymerization time because the productivity as a whole decreases.

(6) A method in which ethylene is used in a larger amount than propylene in the latter mixing ratio of ethylene and propylene. However, this method is not preferable because the production rate of the random copolymer is lowered, the ethylene homopolymer is easily produced, and the effect of improving the impact resistance of the propylene block copolymer is lowered.

(7) A method of adding a specific compound at the time of copolymerization in the latter stage. However, in this method, for example,
When an organoaluminum compound is added, lumps may be formed due to the adhesion of polymers in the reactor, which may cause a trouble in operation (JP-A-53-30686). Further, a method of adding aluminum alkoxide has been proposed, but there is a problem that the stereoregularity is remarkably lowered and the polymers adhere to each other.

A technique using alkyllithium or alkylmagnesium for the purpose of preventing the adhesion of polymers to each other has been disclosed, but the copolymerization activity is remarkably reduced (Japanese Patent Laid-Open Nos. 62-132912 and 62-62). -135509 bulletin,
JP-A-2-117905).

As a method for preventing the adhesion of polymers to each other and improving the copolymerization activity, a method has been proposed in which both titanium alkoxide and hydrocarbon are coexistingly added using a titanium trichloride catalyst system. (Kaisho No. 58-213012), it is clarified that, in the absence of this requirement, these effects are not exhibited at all.

As a method for improving the fluidity of the block copolymer, a method of adding a metal alkoxide (Japanese Patent Laid-Open No. 61-61160).
-69823), a method of adding a compound having a Si-O-C bond (JP-A-61-215613), a method of adding siloxanes (JP-A-63-146914), and a silicon compound. Method of addition (JP-A-3-292311, JP-A-4-29
No. 136010) has been proposed, but there are some problems such as reduced activity or reduced stereoregularity.

On the other hand, as a method of reducing the production of by-products and improving the processability of the block copolymer, a technique of adding a special electron donor has also been proposed (JP-A-56-151).
713, JP 60-59139 JP, JP 61-69821 JP, JP 61-69822 JP, JP 61-69823 JP,
JP-A-63-43915). However, there are drawbacks such that the polymerization activity is lowered and the amount of the additive used is large, resulting in high cost.

[0017]

It is an object of the present invention to remedy the above-mentioned drawbacks and to easily produce a block copolymer having a remarkably improved copolymerization activity and excellent fluidity in the latter gas phase copolymerization reaction. Is to provide a technology that can.

[0018]

DISCLOSURE OF THE INVENTION The present invention is directed to the presence of a catalyst containing (A) a titanium-containing solid catalyst component, (B) an organoaluminum compound component and (C) an electron donating compound.
Polymerization of propylene or propylene with other α-olefins is carried out in the first step, and subsequently, halogenated ether is added in the second step without deactivating the catalyst system described above to obtain propylene and α other than propylene. -A method for producing a propylene block copolymer, characterized by carrying out a gas phase copolymerization with an olefin.

Examples of the titanium-containing solid catalyst as the component (A) of the present invention include supported high activity catalysts.
Here, a catalyst solid component containing magnesium, titanium, a halogen element and an electron donor as essential components can be used. The method for producing the catalyst solid component is not particularly limited,
For example, JP-A-54-94590, JP-A-56-55405,
56-45909, 56-163102, 57-63310, 57-115408, 58-83006, 58-830
16, gazette 58-138707 gazette, gazette 59-149905 gazette,
60-23404, 60-32805, 61-18330, 61-55104, JP2-77413, 2-11
The method proposed in Japanese Patent No. 7905 can be adopted. As a typical production method, (1) a method in which a magnesium compound such as magnesium chloride, an electron donor, and a titanium halide compound such as TiCl ₄ are co-ground, (2) a magnesium compound and an electron donor are dissolved in a solvent. A method in which a titanium halide compound is added to this solution to precipitate a catalyst solid can be mentioned.

In the present invention, the catalyst solid components described in JP-A-60-152511, JP-A-61-31402 and JP-A-62-81405 are particularly preferable for achieving the effects of the present invention. According to these production methods, an aluminum halide is reacted with an organosilicon compound, and then a Grignard compound is reacted to precipitate a solid. As the aluminum halide that can be used in the above reaction, anhydrous aluminum halide is preferable, but it is difficult to use completely anhydrous aluminum halide due to hygroscopicity, and aluminum halide containing a trace amount of water should also be used. You can Specific examples of aluminum halides include aluminum trichloride, aluminum tribromide and aluminum triiodide, with aluminum trichloride being particularly preferred.

Specific examples of the organosilicon compound used in the above reaction include tetramethoxysilane, tetraethoxysilane, tetrabutoxysilane, methyltriethoxysilane, ethyltributoxysilane, phenyltrimethoxysilane, phenyltributoxysilane, Examples thereof include methoxysilane compounds and dimethoxysilane compounds such as dimethyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, trimethylmonoethoxysilane, and trimethylmonobutoxysilane. Particularly, tetraethoxysilane, methyltriethoxysilane, phenyltrimethoxysilane and dimethyldiethoxysilane are preferable.

The amount of the compound used in the reaction between the aluminum halide and the organosilicon compound is determined by the element ratio (Al / Si).
Is usually in the range of 0.4 to 1.5, preferably 0.7 to 1.3, and it is preferable to use an inert solvent such as hexane or toluene in the reaction. Reaction temperature is usually 10-100
℃, preferably 20 ~ 80 ℃, the reaction time is usually 0.2 ~
5 hours, preferably 0.5 to 3 hours.

Specific examples of the Grignard compound used in the above reaction include ethyl magnesium chloride, propyl magnesium chloride, butyl magnesium chloride, hexyl magnesium chloride, octyl magnesium chloride, ethyl magnesium bromide, propyl magnesium bromide, butyl magnesium bromide, ethyl. Organic magnesium halides such as magnesium iodide may be mentioned. As the solvent of the Grignard compound, for example, diethyl ether,
Aliphatic ethers such as dibutyl ether, diisopropyl ether and diisoamyl ether, and aliphatic cyclic ethers such as tetrahydrofuran can be used.

The amount of the Grignard compound used is usually 0.5 to 3, preferably 1.5 to 2.3 in terms of the element ratio (Mg / Al) to the aluminum halide used in the preparation of the reaction product of the above-mentioned aluminum halide and organosilicon compound. It is a range. The reaction temperature is usually -50 to 100 ° C, preferably-
20 to 50 ° C, reaction time is usually 0.2 to 5 hours, preferably 0.
5 to 3 hours.

The white solid obtained in the reaction between the aluminum halide and the organosilicon compound and then the reaction with the Grignard compound is contact-treated with an electron donor and a titanium halide compound. Alternatively, the solid is contact-treated with an electron donor and then with a titanium halide compound. As the contact treatment, a conventionally well-known method can be adopted. For example, the above solid is dispersed in an inert solvent and the electron donor or / and the titanium halide compound is dissolved therein, or an electron donor or / and a liquid titanium halide compound is used without using an inert solvent. Disperse the solid in. In this case, the contact treatment between the solid and the electron donor or / and the titanium halide compound is stirred, and the temperature is usually
50 to 150 ℃, contact time is not particularly limited, but usually 0.2
It can be done in ~ 5 hours. Further, this contact treatment can be performed multiple times.

Titanium halide compounds that can be used in the contact treatment include tetrachlorotitanium, tetrabromotitanium, trichloromonobutoxytitanium, tribromomonoethoxytitanium, trichloromonoisopropoxytitanium,
Examples thereof include dichlorodiethoxy titanium, dichlorodibutoxy titanium, monochlorotriethoxy titanium, monochlorotributoxy titanium and the like. Particularly, tetrachlorotitanium and trichloromonobutoxytitanium are preferable.

The electron donor used in the above contact treatment is preferably an aromatic ester, of which orthophthalic acid diester is particularly preferable. Specific examples of the diester include diethyl orthophthalate, diisobutyl orthophthalate, dipentyl orthophthalate, dihexyl orthophthalate, di-2-ethylhexyl orthophthalate, and di-n-heptyl orthophthalate.

After the above-mentioned catalytic treatment, the treated solid is generally separated from the treated mixture and thoroughly washed with an inert solvent, and the obtained solid can be used as the catalyst solid component (A) of the present invention.

As the organoaluminum compound as the component (B) in the present invention, halogenoalkylaluminum, trialkylaluminum and the like can be used.

Specific examples of the halogenoalkyl aluminum include diethyl aluminum monochloride, dibutyl aluminum monochloride, dinormalpropyl aluminum monochloride, methyl aluminum sesquichloride, ethyl aluminum sesquichloride, butyl aluminum sesquichloride, butyl aluminum sesquiclobromide and the like. Is mentioned.

Specific examples of the trialkyl aluminum include trimethyl aluminum, triethyl aluminum, triisobutyl aluminum, trihexyl aluminum, trioctyl aluminum and the like.

Any of the above organoaluminum compounds can be used as a mixture. Further, polyaluminoxane obtained by the reaction of alkylaluminum and water can be used as well.

When a catalyst solid that essentially contains magnesium, titanium, a halogen element and an electron donor is used as the catalyst (A) component, trialkylaluminum is preferably used as the organoaluminum compound of the catalyst (B) component. The amount of trialkylaluminum used is such that the element ratio of aluminum to titanium (A in the catalyst solids that essentially contains magnesium, titanium, halogen elements and electron donors
l / Ti), preferably 20 to 1000, particularly preferably 150 to
500.

As the electron-donating compound of the component (C), an alkoxy group-containing silicon compound such as alkoxysilane, an organic acid ester, an inorganic acid ester, an acid halide,
Ethers, acid amides, N, N-dialkyl acid amides, amines, nitriles, acid anhydrides, ketones, alcohols, aldehydes, carboxylic acids, isocyanates and the like can be used. Among them, an alkoxy group-containing silicon compound can be preferably used. Specific examples of the alkoxy group-containing silicon compound, t-butylmethyldimethoxysilane, t-butylethyldimethoxysilane, t-butylpropyldimethoxysilane, di-t-butyldimethoxysilane,
Diisopropyldimethoxysilane, cyclohexylmethyldimethoxysilane, cyclohexylethyldimethoxysilane, dicyclohexyldimethoxysilane, dicyclopentyldimethoxysilane, tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetra-n-butoxysilane, tetra-isopentoxy Silane, tetra-n-hexoxysilane, methyltrimethoxysilane, methyltriethoxysilane, methyltri-n-butoxysilane, methyltriisopentoxysilane, methyltri-n-hexoxysilane, ethyltriethoxysilane, ethyltriisopropoxysilane, ethyl Triisopentoxysilane, n-butyltriethoxysilane, isobutyltriethoxysilane, isopentyltriethoxysilane, isopentyltriethoxysilane n-butoxysilane, dimethyldiethoxysilane, dimethyldi-n-butoxysilane,
Dimethyldiisopentoxysilane, diethyldiethoxysilane, diethyldiisopentoxysilane, diisobutyldiisopentoxysilane, di-n-butyldiethoxysilane, diisobutyldiisopentoxysilane, trimethylmethoxysilane, trimethylethoxysilane, Trimethylisobutoxysilane, triethylisopropoxysilane, tri-n-propylethoxysilane, tri-n-butylethoxysilane, triisopentylethoxysilane,
Phenyltriethoxysilane, phenyltriisobutoxysilane, phenyltriisopentoxysilane, diphenyldiethoxysilane, diphenyldiisopentoxysilane, diphenyldioctoxysilane, triphenylmethoxysilane, phenylmethyldimethoxysilane, triphenylethoxysilane , Triphenylisopentoxysilane, benzyltriethoxysilane, benzyltributoxysilane, dibenzyldiethoxysilane, cyclopentyltrimethoxysilane, cyclohexylmethyldimethoxysilane, 2-methylcyclopentyltrimethoxysilane, 2,3-dimethylcyclopentyltrimethoxysilane Alkoxysilane compounds such as silane, cyclopentyltriethoxysilane, tricyclopentylethoxysilane or dialkoxysilane compounds. Emission compounds. Two or more kinds of these alkoxy group-containing silicon compounds such as alkoxysilane compounds or dialkoxysilane compounds may be used in combination.

The amount of the electron-donating compound used is the same as that of the component (B).
It is preferably 0.01 to 5 mol, and particularly preferably 0.1 to 1 mol per mol.

The first-stage polymerization may be either homopolymerization of propylene or copolymerization of propylene with another α-olefin. As the α-olefin, ethylene, butene-1, 3-methylbutene-1, 3-methylpentene-1, 4-methylpentene-1, hexene-1, 4-methylhexene-1, octene-1, styrene, 2 -Acyclic monoolefins such as methylstyrene, 3-methylstyrene, 4-methylstyrene, vinylcyclohexane, vinylcyclopentane, 2-vinylnaphthalene, 9-vinylanthracene, cyclopentene,
Cyclohexene, cyclic monoolefins such as norbornene, dicyclopentadiene, 5-ethylidene norbornene
Examples thereof include diolefins such as -2,4-vinylcyclohexene and 1,5-hexadiene.

The proportion of α-olefin other than propylene in the crystalline polymer obtained in the first step is preferably an amount that does not impair the characteristics of polypropylene, for example, 10% by weight or less. When the proportion of α-olefin other than propylene in the crystalline polymer exceeds 10% by weight, the amount of low crystalline polymer by-products increases.

If necessary, hydrogen may be added as a chain transfer agent in order to adjust the molecular weight of the produced polymer.

In the first stage, after producing a crystalline polymer by homopolymerization of propylene or copolymerization of propylene with other α-olefins, the catalyst system described above is not deactivated and subsequently the second Halogenated ether and organoaluminum compound were added at the stage of propylene and α other than propylene.
To produce a propylene block copolymer by vapor phase copolymerization with an olefin.

Specific examples of the halogenated ether include bis-2-chloroethyl ether, bis-2-chloropropyl ether, bis-3-chloropropyl ether and bis-2-.
Bis-chloroalkyl ethers such as chlorobutyl ether and bis-3-chlorobutyl ether, bis-2-bromoethyl ether, bis-2-bromopropyl ether, bis-3-bromopropyl ether, bis-2-bromobutyl ether, bis- Bis-bromoalkyl ether such as 3-bromobutyl ether, 2-chloroethyl methyl ether, 2-chloroethyl ethyl ether, 2-chloroethyl alkyl ether such as 2-chloroethyl propyl ether, 2-bromoethyl methyl ether, 2-bromo Such as ethyl ethyl ether, 2-bromoethyl propyl ether
2-Bromoethyl alkyl ether and the like can be mentioned. Among these, bis-2-chloroethyl ether and 2-chloroethyl methyl ether can be preferably used.
You may use the said compound in mixture of 2 or more types. The amount of the halogenated ether used is not particularly limited,
The molar ratio to the organoaluminum compound as the component (B) is usually 0.001 to 1.0, and more preferably 0.01 to 1.0.
It is 0.6. When the amount used is in the above range, the polymerization activity of the gas phase copolymerization reaction is further improved.

In the present invention, it is preferable to add an organoaluminum compound together with a halogenated ether in the second step to carry out a gas phase copolymerization reaction because the polymerization activity is further improved. Specific examples of the organoaluminum compound include (B)
The same as the component organoaluminum compound may be mentioned. Among them, trialkylaluminum such as trimethylaluminum, triethylaluminum, triisobutylaluminum, trihexylaluminum and trioctylaluminum can be preferably used. The amount of the organoaluminum compound used is not particularly limited,
The molar ratio to halogenated ether is usually 0.001
-100, more preferably 0.01-50. When the amount used is in the above range, the polymerization activity of the gas phase copolymerization reaction is further improved.

The halogenated ether and the organoaluminum compound may be added to the polymerization system as a solution of a hydrocarbon compound having no ethylenically unsaturated double bond. Specific examples of the hydrocarbon compound having no ethylenically unsaturated double bond include butane, pentane, hexane,
Examples thereof include aliphatic hydrocarbon compounds such as heptane, octane, decane, and dodecane, alicyclic hydrocarbon compounds such as cyclohexane and methylcyclohexane, and halides thereof. Among them, hexane and heptane can be preferably used. The amount of use of these hydrocarbon compounds having no ethylenically unsaturated double bond is not particularly limited as long as it is an amount that forms a saturated vapor pressure under gas phase copolymerization conditions, but it is obtained in the first step. Crystalline polypropylene 1
It is preferably 0.1 to 500 g, especially 1 to 200 g per kg.

The method of adding the halogenated ether and the organoaluminum compound, or a solution of these compounds, which is a hydrocarbon compound having no ethylenically unsaturated double bond, to the polymerization system is not particularly limited and may be added at once. It is possible to use a method of adding by adding, a method of adding continuously, a method of adding intermittently, and the like. Of these, the method of continuous addition is preferable. In the case of the continuous addition method, the addition rate is preferably 0.01 to 3 g per 1 kg of the crystalline polypropylene obtained in the first step.

The proportion of the rubbery copolymer of propylene and the α-olefin other than propylene obtained in the second step is
It is usually 3 to 40% by weight, more preferably 5 to 30% by weight, based on the total amount of the block copolymer. The proportion of α-olefin other than propylene in the rubbery copolymer is preferably 10 to 40% by weight.

As the polymerization mode of the present invention, bulk polymerization in which a monomer in a liquid state is polymerized therein as a solvent is carried out in the first step, and vapor phase polymerization in which the monomer is brought into contact with a catalyst in a gaseous state is carried out in the second step. be able to.

The bulk polymerization is preferably carried out under conditions of temperature and pressure at which propylene or a mixed monomer of propylene and another α-olefin can be kept in a liquid state. The polymerization temperature is usually 30 to 90 ° C, preferably 50 to 80 ° C. The polymerization time is usually 5 minutes to 5 hours.

In the gas phase polymerization, propylene or a mixed monomer of propylene and other α-olefin is introduced, and the gas phase polymerization is carried out under the temperature and pressure conditions capable of maintaining the gas phase state. α-
As the olefin, ethylene, butene-1,3-methylbutene-1,3-methylpentene-1,4-methylpentene-1, hexene-1,4-methylhexene-1, octene-1, styrene, 2-methyl Acyclic monoolefins such as styrene, 3-methylstyrene, 4-methylstyrene, vinylcyclohexane, vinylcyclopentane, 2-vinylnaphthalene, 9-vinylanthracene, cyclopentene, cyclohexene, norbornene and other cyclic monoolefins, dicyclopentadiene, Mention may be made of a diolefin such as 5-ethylidene norbornene-2,4-vinylcyclohexene or 1,5-hexadiene.

The copolymerization pressure is usually from atmospheric pressure to 20 kg / cm ² ,
Preferably atmospheric pressure ~ 10kg / cm ² , the polymerization temperature is usually 30 ~
The temperature is 95 ° C, preferably 40 to 70 ° C. Polymerization time is usually 30
Minutes to 10 hours, preferably 1 to 5 hours.

When a solid catalyst component (A) is a catalyst solid containing magnesium, titanium, a halogen element and an electron donor as an essential component, before the first stage polymerization,
It is also possible to pre-polymerize a limited amount of propylene using the solid catalyst component (A) in the presence of the organoaluminum component (B) and the silicate compound component (C).
By using the prepolymerized solid or the solid washed after the prepolymerization for the main polymerization, the polymerization activity per solid catalyst and the stereoregularity of the polymer can be improved. In the present invention, when the prepolymerized solid is used as a solid catalyst component in the main polymerization, the silicate compound component (C) can be omitted in the main polymerization.

The prepolymerization in the present invention can be carried out by a gas phase method, a slurry method, a bulk method or the like. The solid obtained in the prepolymerization can be separated and then used in the main polymerization, or the main polymerization can be continuously carried out without separation.

The prepolymerization time is usually 0.1 to 10 hours,
It is preferable to continue the prepolymerization until 0.1 to 100 g of the prepolymer is produced per 1 g of the solid catalyst component. Solid catalyst component
If it is less than 0.1 g per 1 g, the main polymerization activity will be insufficient and the catalyst residue will be large, and the stereoregularity of polypropylene will be insufficient. If it exceeds 100 g, the crystallinity of polypropylene tends to decrease. The prepolymerization temperature is 0 to 100 ° C,
It is preferably carried out at 5 to 60 ° C in the presence of each catalyst component. 50 ° C
When the prepolymerization is carried out at a temperature as high as above, it is preferable to reduce the propylene concentration or shorten the polymerization time. Depending on the prepolymerization conditions, it may be difficult to control the production of 0.1 to 100 g of the prepolymer per 1 g of the solid catalyst component, and the crystallinity of the polypropylene obtained by the main polymerization will decrease.

The amount of the organoaluminum component used in the prepolymerization is usually 0.5 to 1000, preferably 1 to 500, in terms of the Al / Ti element ratio based on the titanium atom of the solid catalyst component. The amount of silicate compound used is usually 0.01 to 60% Si / Al element ratio with respect to the aluminum atoms of the organoaluminum compound component.
1, preferably 0.1 to 0.5. In the preliminary polymerization, hydrogen can be allowed to coexist if necessary.

[0053]

EFFECTS OF THE INVENTION According to the present invention, a propylene block copolymer having a high molecular weight of a rubbery copolymer component of propylene and α-olefin and having good fluidity can be stably and efficiently produced with high copolymerization activity. can do.

[0054]

EXAMPLES Examples of the present invention will be described below. In the examples, the copolymer ratio is a polymer weight ratio in the second stage in the total polymer (polymer yield in the second stage / total polymer yield × 100%).

Example 1 (1) Preparation of solid catalyst component (A) 15 mmol of anhydrous aluminum chloride was added to 50 ml of toluene, and 15 mmol of methyltriethoxysilane was further added dropwise thereto at 25 ° C. with stirring. The reaction was carried out at the same temperature for 1 hour. This reaction product was cooled to -5 ° C, 20 ml of a diisoamyl ether solution containing 30 mmol of butylmagnesium chloride was added dropwise to the reaction product over 30 minutes with stirring, and the mixture was kept at the same temperature for 30 minutes and then cooled to 25 ° C. The temperature was raised in 30 minutes. After reacting for 1 hour at the same temperature, the precipitated solid was filtered off, washed with toluene and heptane, dispersed in 30 ml of toluene, and 150 ml of titanium tetrachloride and di-n-heptyl phthalate were dispersed.
4.0 mmol was added and reacted at 90 ° C. for 1 hour. Separate the solid at the same temperature, wash with toluene and heptane, and then disperse the solid again in 30 ml of toluene.
0 ml was added and the mixture was contacted at 90 ° C. for 1 hour, the catalyst solid was separated, and thoroughly washed with toluene and heptane. 30 catalyst solids
After drying in a nitrogen atmosphere at ℃, measure the titanium content, 2.
A value of 7 wt% was obtained.

(2) Prepolymerization After weighing a 2 L stainless steel autoclave with a stirrer, 2 ml of n-hexane solution of triethylaluminum in nitrogen was weighed.
3.3 ml (0.3 mmol) of diisopropyldimethoxysilane solution diluted with (1.8 mmol) and n-heptane, 7.0 kg / cm ^{2 of} hydrogen at gauge pressure, and 900 ml of liquid propylene were charged into the autoclave and stirred for 10 minutes for 10 minutes. It was set to ° C. Next prepared catalyst solid 8.0 mg (titanium content
2.7 wt%) was injected under pressure, and propylene was prepolymerized at the same temperature for 10 minutes.

(3) First Stage Polymerization Reaction in Liquid Propylene Immediately after the completion of prepolymerization, the autoclave was placed in another bath 60
The mixture was heated to 0 ° C., and bulk polymerization of propylene was carried out at the same temperature for 15 minutes while stirring. Next, the unreacted gas was discharged to the outside of the system, the inside was sufficiently replaced with nitrogen, and the pressure of the autoclave was maintained at 0.25 kg / cm ² with a gauge pressure, and then the weight was measured. The polypropylene yield was calculated to be 110 g.

(4) Second-stage gas phase copolymerization reaction The temperature of the autoclave after completion of bulk polymerization in which the system was maintained at 0.25 kg / cm ² at a gauge pressure was set to 40 ° C., and a mixed gas of ethylene and propylene was mixed. Was supplied into the autoclave at a volume ratio of 1: 1 (each 150 Ncc / min), and the copolymerization pressure was adjusted to 2.0 kg / cm ² with a gauge pressure. When carrying out the copolymerization reaction at the same temperature and pressure for 3 hours, n-heptane 10m
The entire amount of a solution containing 0.09 mmol of bis-2-chloroethyl ether diluted with 1 and 0.09 mmol of triethylaluminum was continuously introduced into the system under pressure. The unreacted gas was discharged outside the system so that the copolymerization pressure was maintained at 2.0 kg / cm ² as a gauge pressure, and the copolymerization reaction was carried out at 40 ° C. for 3 hours. Next, when the lid was opened and the inside of the autoclave was observed, adhesion of the polymer was not recognized on the wall or the stirring blade at all,
The fluidity of the polymer particles was also very good. The obtained copolymer was dried under reduced pressure at 60 ° C. for 20 hours and weighed to find that the yield was 149 g. Therefore, the polymer weight obtained in the second stage gas phase copolymerization reaction was 39 g, and the copolymer ratio was 26.17 wt%.

Example 2 A propylene block copolymer was prepared in the same manner as in Example 1 except that 2-chloroethyl methyl ether was used instead of bis-2-chloroethyl ether in the second stage gas phase copolymerization reaction. A polymer was produced. The yield of polypropylene after the completion of the first-stage bulk polymerization reaction was 109 g, and the total yield after the second-stage gas phase copolymerization reaction was 145 g. Inside the autoclave, no polymer adhesion was observed on the walls or stirring blades, the fluidity of the polymer particles was also very good, and the polymer yield obtained during the gas phase copolymerization reaction was 36 g. Was 24.83 wt%.

Example 3 A propylene block copolymer was produced in the same manner as in Example 1 except that the amount of bis-2-chloroethyl ether added was 0.05 mmol in the second stage gas phase copolymerization reaction. . The yield of polypropylene after the completion of the first-stage bulk polymerization reaction was 111 g, and the total yield after the second-stage gas phase copolymerization reaction was 146 g. Inside the autoclave, no adhesion of polymer was observed on the walls or stirring blades, the fluidity of polymer particles was also very good, and the polymer yield obtained during the gas phase copolymerization reaction was 35 g. Is 23.97 wt%
Met.

Comparative Example 1 In the second stage gas phase copolymerization reaction, a halogenated ether,
A propylene block copolymer was produced by the same operation as in Example 1 without adding any organoaluminum compound and hydrocarbon compound. The yield of polypropylene after the completion of the first-stage bulk polymerization reaction was 111 g, and the total yield after the second-stage gas phase copolymerization reaction was 123 g. Inside the autoclave, white powder was attached to the walls and stirring blades, and the copolymer at the bottom was partially agglomerated. The polymer yield obtained during the gas phase copolymerization reaction was 12 g, and the copolymer ratio was 9.76 wt.
% Met.

[Brief description of drawings]

FIG. 1 is a flow chart showing a preparation process and a polymerization process of a catalyst of the present invention.

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[Procedure amendment]

[Submission date] January 14, 1994

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(4) A method of increasing the copolymerization amount in the latter stage by increasing the copolymerization pressure in the latter stage. However, in this method, there is a problem in that there are restrictions on the apparatus, and if the equipment is used to increase the pressure resistance, the equipment cost will increase, which in turn will lead to an increase in the cost of the product.

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[Document name to be amended] Statement

[Name of item to be corrected] 0030

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Specific examples of the halogenoalkyl aluminum include diethyl aluminum monochloride, dibutyl aluminum monochloride, dinormalpropyl aluminum monochloride, methyl aluminum sesquichloride, ethyl aluminum sesquichloride, butyl aluminum sesquichloride, butyl aluminum sesquibromide and the like. Can be mentioned.

Claims (1)

[Claims] 1. A solid catalyst component containing titanium (A), and (B)
Polymerization of propylene or propylene with another α-olefin is carried out in the first step in the presence of a catalyst containing an organoaluminum compound component and (C) an electron-donating compound, and subsequently the above catalyst system is deactivated. In the second step, a halogenated ether was added and propylene and α-other than propylene were added.
A method for producing a propylene block copolymer, which comprises performing gas phase copolymerization with an olefin.