JPH05301918A - Olefin-polymerization catalyst and polymerization process - Google Patents

Abstract

PURPOSE:To provide the subject catalyst composed of a specific solid catalyst component, an organic aluminum compound and an organic silicon compound and capable of giving a polyolefin having broad molecular weight distribution and excellent stereoregularity in high yield. CONSTITUTION:The objective catalyst is produced by compounding (A) a solid catalyst component obtained by forming a suspension from (i) a dialkoxymagnesium (preferably diethoxymagnesium) and (ii) an aromatic hydrocarbon which is liquid at normal temperature (e.g. benzene), adding (iii) titanium tetrachloride to the suspension at a volume ratio of <=1/2 based on the component ii, heating the mixture, adding (iv) a phthalic acid diester (e.g. dimethyl phthalate), heating the mixture, reacting at 80-130 deg.C, washing the obtained solid substance with an aromatic hydrocarbon (the component ii may be used as the hydrocarbon), adding the component (iii) to the product at a volume ratio of <=1/2 based on the component ii and reacting at 80-130 deg.C, (B) an organic aluminum compound and (C) a compound of formula (C6H11 is cyclohexyl; R is 1-5C alkyl).

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a catalyst for olefin polymerization capable of obtaining a polyolefin having a wide molecular weight distribution and excellent stereoregularity in a high yield, and a polymerization of olefins in the presence of the catalyst. Regarding the method.

[0002]

2. Description of the Related Art Solid catalyst components for polymerization of olefins containing titanium halides, magnesium compounds and electron donating compounds as essential components, and electron donating properties of the solid catalyst components and third components such as organoaluminum compounds and silicon compounds. A number of proposals have been made and known for olefin polymerization methods in which olefins are polymerized or copolymerized in the presence of an olefin polymerization catalyst comprising a compound.

For example, Japanese Patent Application Laid-Open No. Sho 6-1994 filed by the applicant of the present application
No. 3-3010, a product obtained by contacting dialkoxymagnesium, diester of aromatic dicarboxylic acid, aromatic hydrocarbon and titanium halide,
A catalyst for olefin polymerization comprising a solid catalyst component prepared by heat treatment in a powder state and an organoaluminum compound and an organosilicon compound is proposed, and an olefin polymerization method in the presence of the catalyst is exemplified in the examples. Has been done.

Similarly, in JP-A-63-154705, a magnesium compound obtained by reacting a metal magnesium powder with an alkyl monohalide in the presence of iodine, tetraalkoxytitanium,
Titanium tetrachloride was added to a mixed solution of an aliphatic hydrocarbon and an aliphatic alcohol to precipitate a solid substance, and a diester of phthalic acid was added to the obtained solid product to give a solid product in the presence of an aromatic hydrocarbon. A catalyst for olefin polymerization, which comprises a solid catalyst component prepared by bringing titanium chloride into contact with an organoaluminum compound and a silicon compound, has been proposed, and an olefin polymerization method in the presence of the catalyst is exemplified.

Further, in JP-A-1-221405, titanium tetrachloride is brought into contact with a suspension formed of diethoxymagnesium and an alkylbenzene, and then a silicon compound and phthalic acid dichloride are added and reacted. A solid catalyst component, which is prepared by obtaining a solid product, washing the solid product with alkylbenzene, and then catalytically reacting with titanium tetrachloride in the presence of alkylbenzene, and an organoaluminum compound and an organosilicon compound. A catalyst for polymerizing olefins has been proposed, and a method for polymerizing an olefin in the presence of the catalyst is exemplified.

[0006]

The above-mentioned respective prior arts are catalysts having such a high activity that their purpose is to omit a so-called deashing step of removing catalyst residues such as chlorine and titanium remaining in the produced polymer. It originated in the development of the components, and also contributed to the improvement of the yield of the stereoregular polymer and the enhancement of the sustainability of the catalytic activity during the polymerization.

Recently, however, it has been obtained by a polymerization reaction using an olefin polymerization catalyst comprising such a highly active catalyst component, an organoaluminum compound and an electron donating compound represented by a silicon compound as a third component. The obtained polymer is obtained by a polymerization reaction using a catalyst for olefin polymerization in which a conventional titanium trichloride-type catalyst component is combined with an organoaluminum compound and an electron-donating compound which is a third component optionally used. It has been pointed out that the molecular weight distribution is narrower than that of the polymer, and as a result, there remains a problem that the use thereof is limited to some extent such as impairing the moldability of the final product polyolefin.

As one of means for solving such a problem,
Various attempts have been made, for example, by adopting a multistage polymerization method to obtain a polymer having a wide molecular weight distribution. However, the multi-stage polymerization method is not preferable in terms of cost, such as performing complicated polymerization operations in duplicate and collecting the chelating agent used during polymerization.

Therefore, in JP-A-3-7703,
Presence of a catalyst for olefin polymerization formed from a solid titanium catalyst component containing magnesium, titanium, halogen and an electron donor as essential components, an organoaluminum compound and at least two or more electron donors (organosilicon compounds) Below, methods of polymerizing olefins have been proposed.

According to the above-mentioned polymerization method, the complicated multi-step polymerization method is omitted, and it is said that a desired polymer having a wide molecular weight distribution can be obtained. However, electron donation at the time of polymerization of two or more kinds of organosilicon compounds. Further improvement has been desired in terms of complexity of processing operations, such as use as a body being an essential requirement.

The present inventors have made it possible to obtain a polymer having a broad molecular weight distribution while maintaining a desired high polymerization activity and a stereoregular polymer yield with a simpler operation. As a result of various studies aimed at developing the above-mentioned polymerization method, it was found that such a problem can be solved by using a specific organosilicon compound as a catalyst component for olefin polymerization, and the present invention has been completed.

[0012]

Means for Solving the Problems That is, the present invention provides (A)
In a suspension formed of (a) dialkoxymagnesium and (b) aromatic hydrocarbon that is liquid at room temperature, (c) titanium tetrachloride and ( d) The temperature is raised to 80 after adding the diester of phthalic acid.
The solid substance obtained by reacting in the temperature range of ~ 130 ° C,
After washing with aromatic hydrocarbon, (b) titanium tetrachloride (C) having a volume ratio to the aromatic hydrocarbon of 1/2 or less is added in the presence of the aromatic hydrocarbon which is liquid at room temperature,
0 solid catalyst component (B) an organoaluminum compound obtained by reacting in a temperature range of ℃ and (C) the general formula _{Si (C 6 H 11) 2} (OR) 2 ( wherein C ₆ H ₁₁
Is a cyclohexyl group, and R is an alkyl group having 1 to 5 carbon atoms. The present invention provides an olefin polymerization catalyst characterized by comprising an organosilicon compound represented by the formula (4), and an olefin polymerization method characterized by carrying out olefin polymerization in the presence of the catalyst.

The dialkoxy magnesium (a) used in the present invention (hereinafter sometimes simply referred to as the substance (a)) includes diethoxy magnesium, dibutoxy magnesium, diphenoxy magnesium, dipropoxy magnesium and di-. sec-butoxy magnesium,
Examples thereof include di-tert-butoxy magnesium and diisopropoxy magnesium, with diethoxy magnesium being preferred.

Examples of the aromatic hydrocarbon (b) which is liquid at room temperature (hereinafter sometimes simply referred to as (b) substance) used in the present invention include benzene, toluene, xylene, ethylbenzene, propylbenzene, trimethylbenzene and the like. can give.

Examples of the (d) phthalic acid diester used in the present invention (hereinafter sometimes simply referred to as (d) substance) include dimethyl phthalate, diethyl phthalate, diisopropyl phthalate, dipropyl phthalate, dibutyl phthalate, diisobutyl phthalate, Examples thereof include diamyl phthalate, diisoamyl phthalate, ethyl butyl phthalate, ethyl isobutyl phthalate and ethyl propyl phthalate.

Examples of the organoaluminum compound (B) used for forming the catalyst in the present invention include trialkylaluminum, dialkylaluminum halide, alkylaluminum dihalide and mixtures thereof.

[0017] The used in the catalyst formation of the present invention (C) the general formula _{Si (C 6 H 11) 2} (OR) 2 ( wherein C ₆ H ₁₁
Is a cyclohexyl group, and R is an alkyl group having 1 to 5 carbon atoms. Examples of the organosilicon compound represented by) include dicyclohexyldimethoxysilane, dicyclohexyldiethoxysilane, dicyclohexylpropoxysilane, and dicyclohexyldibutoxysilane.

Next, the method for preparing the solid catalyst component (A) of the present invention will be described.

First, the respective components may be used in any ratios so long as the substances (a) and (b) can form a suspension, and (c) titanium tetrachloride (hereinafter simply referred to as ( c)
(Sometimes referred to as a substance) is 1.0 g or more for 1.0 g of the substance (a), and is 1 / the volume ratio to the substance (b).
It is 2 or less. In addition, (d) substance is (a) substance 1.0 g
On the other hand, it is used in the range of 0.1 to 1.0 g.

The suspension of the substances (a) and (b) is usually formed by stirring at room temperature to a temperature not higher than the boiling point of the substance (b) for 100 hours or less, preferably 10 hours or less. At this time, it is necessary to take care so that the suspension does not become a uniform solution.

The contact between the suspension and the substance (c) is usually carried out in the vicinity of room temperature, preferably in the temperature range of 5 to 20 ° C. Further, the contact with the substance (d) is performed in a temperature range of 5 to 110 ° C.,
Thereafter, the temperature is raised and the reaction is performed while stirring in the temperature range of 80 to 130 ° C. for 10 minutes to 10 hours.

The solid substance obtained after the completion of the reaction is washed with an aromatic hydrocarbon, and the aromatic hydrocarbon may be the same as or different from the substance (b).

After the completion of washing, the solid substance is further added to the substance (b) in the presence of the substance (b) and a substance (c) having a volume ratio to the substance (b) of 1/2 or less is added, and the temperature is in the range of 80 to 130 ° C for 10 minutes. ~
The solid catalyst component (A) is prepared by reacting with stirring for 10 hours.

The solid catalyst component (A) is washed with an inert organic solvent such as n-heptane and then left as it is or dried to form the olefin polymerization catalyst of the present invention.

The solid catalyst component (component A) thus prepared is the above-mentioned organoaluminum compound (component B).
And the above general formula Si (C ₆ H ₁₁ ) ₂ (OR) ₂ (wherein C ₆ H
₁₁ is a cyclohexyl group, and R is an alkyl group having 1 to 5 carbon atoms. ) And an organosilicon compound (component C) represented by the formula (1) to form the olefin polymerization catalyst of the present invention.

The amounts of these components used are such that the organoaluminum compound (component B) is 5 to 1000 and the organosilicon compound (component C) is the molar ratio per mole of titanium atoms in the solid catalyst component (component A). The molar ratio of the organoaluminum compound (component B) is in the range of 0.002 to 0.5.

The polymerization can be carried out in the presence or absence of an organic solvent, and the olefin monomer can be used in a gas or liquid state. The polymerization temperature is 200 ° C or lower, preferably 100 ° C or lower, and the polymerization pressure is 100 ° C.
Kg / cm ² · G or less, preferably 50 Kg / cm ² · G
It is below.

The olefins homopolymerized or copolymerized by the method of the present invention include ethylene, propylene, 1-butene,
4-methyl-1-pentene and the like.

[0029]

According to the olefin polymerization catalyst of the present invention and the polymerization method using the catalyst, a polyolefin having a wide molecular weight distribution and excellent stereoregularity can be obtained in a high yield. became. It is presumed that such an action is caused by a special organosilicon compound used at the time of catalyst formation.

[0030]

EXAMPLES AND COMPARATIVE EXAMPLES The present invention will be described in more detail with reference to Examples and Comparative Examples.

<Example 1><Preparation of solid catalyst component> 10 g of diethoxymagnesium and 80 ml of toluene were placed in a suspension state in a round bottom flask having a capacity of 200 ml, which was sufficiently replaced with nitrogen gas and equipped with a stirrer. And then add TiCl ₄ 20 to this suspension.
ml was added and the temperature was raised to 90 ° C. to obtain dibutyl phthalate 2.7.
ml was added, the temperature was further raised to 115 ° C., and the reaction was performed for 2 hours with stirring. After completion of the reaction, toluene at 90 ° C 100m
It was washed twice with 1 times, 20 ml of TiCl ₄ and 80 ml of toluene were newly added, the temperature was raised to 115 ° C., and the reaction was carried out with stirring for 2 hours. After completion of the reaction, 40 ° C. n-heptane 10
The solid catalyst component was washed 10 times with 0 ml. The solid content of the solid catalyst component was separated and the titanium content of the solid content was measured to be 2.61% by weight.

<Formation and Polymerization of Polymerization Catalyst> Triethylaluminum (1.32 mmol) was placed in an autoclave equipped with a stirrer and having an internal volume of 2.0 l, which was completely replaced with nitrogen gas.
0.13 mmol of dicyclohexyldimethoxysilane and 0.0066 mmo of the solid catalyst component as Ti
1 was charged to form a polymerization catalyst. After that, hydrogen gas 1.
Charge 8 liters and 1.4 liters of liquefied propylene, 30 at 70 ℃
A polymerization reaction was carried out for a minute. After the completion of the polymerization reaction, the weight of the produced polymer is defined as (A). This product was extracted with boiling n-heptane for 6 hours to obtain a polymer insoluble in n-heptane, and the weight of this product is designated as (B).

The polymerization activity (C) per solid catalyst component used is represented by the following formula.

[Equation 1]

The yield (D) of all crystalline polymer is represented by the following formula.

[Equation 2]

Further, MI of the produced polymer is represented by (E) and molecular weight distribution is represented by (F), and the obtained results are shown in Table 1.

Example 2 An experiment was conducted in the same manner as in Example 1 except that 60 ml of toluene and 40 ml of TiCl ₄ were used when the solid catalyst component was prepared.

The solid content of the solid catalyst component at this time was separated and the titanium content of the solid content was measured to be 2.69% by weight.
Met. The results obtained are shown in Table 1.

Example 3 Dibutyl phthalate used in the preparation of the solid catalyst component was replaced with dipropyl phthalate of 2.4 m.
An experiment was conducted in the same manner as in Example 1 in which the value was 1.

At this time, the solid-liquid in the solid catalyst component was separated and the titanium content of the solid was measured to be 2.74% by weight.
Met. The results obtained are shown in Table 1.

Comparative Example 1 An experiment was conducted in the same manner as in Example 1 except that phenyltriethoxysilane was used instead of dicyclohexyldimethoxysilane used when forming the polymerization catalyst. The obtained results are as shown in Table 1, but the molecular weight distribution was narrower than that of each example.

[0041]

As shown in Table 1, the molecular weight distribution of the polymer obtained by the present invention is clearly improved as compared with the molecular weight distribution of the polymer obtained by the conventionally known method. Can be applied to a wide range of applications.

Further, since the polymerization activity per catalyst component and the yield of the stereoregular polymer are maintained at a high level, it can be expected to have extremely high industrial practicality.

Further, in the method of polymerizing an olefin in the presence of a highly active catalyst of this kind, a multi-stage polymerization method or a method of using two or more kinds of organosilicon compounds at the time of polymerization is not used, but a special organosilicon compound is used. The feature of the present invention lies in that such an effect is achieved by the obtained catalyst and the polymerization method using the catalyst.

[Table 1]

[Brief description of drawings]

FIG. 1 is a schematic flowchart illustrating the configuration of the present invention.

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[Procedure amendment]

[Submission date] March 22, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Full text

[Correction method] Change

[Correction content]

[Document name] Statement

Title: Olefin polymerization catalyst and polymerization method

[Claims]

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a catalyst for olefin polymerization capable of obtaining a polyolefin having a wide molecular weight distribution and excellent stereoregularity in a high yield, and a polymerization of olefins in the presence of the catalyst. Regarding the method.

[0002]

2. Description of the Related Art Solid catalyst components for polymerization of olefins containing titanium halides, magnesium compounds and electron donating compounds as essential components, and electron donating properties of the solid catalyst components and third components such as organoaluminum compounds and silicon compounds. A number of proposals have been made and known for olefin polymerization methods in which olefins are polymerized or copolymerized in the presence of an olefin polymerization catalyst comprising a compound.

For example, Japanese Patent Application Laid-Open No. Sho 6-1994 filed by the applicant of the present application
No. 3-3010, a product obtained by contacting dialkoxymagnesium, diester of aromatic dicarboxylic acid, aromatic hydrocarbon and titanium halide,
A catalyst for olefin polymerization comprising a solid catalyst component prepared by heat treatment in a powder state and an organoaluminum compound and an organosilicon compound is proposed, and an olefin polymerization method in the presence of the catalyst is exemplified in the examples. Has been done.

Similarly, in JP-A-63-154705, a magnesium compound obtained by reacting a metal magnesium powder with an alkyl monohalide in the presence of iodine, tetraalkoxytitanium,
Titanium tetrachloride was added to a mixed solution of an aliphatic hydrocarbon and an aliphatic alcohol to precipitate a solid substance, and a diester of phthalic acid was added to the obtained solid product to give a solid product in the presence of an aromatic hydrocarbon. A catalyst for olefin polymerization, which comprises a solid catalyst component prepared by bringing titanium chloride into contact with an organoaluminum compound and a silicon compound, has been proposed, and an olefin polymerization method in the presence of the catalyst is exemplified.

Further, in JP-A-1-221405, titanium tetrachloride is brought into contact with a suspension formed of diethoxymagnesium and an alkylbenzene, and then a silicon compound and phthalic acid dichloride are added and reacted. A solid catalyst component, which is prepared by obtaining a solid product, washing the solid product with alkylbenzene, and then catalytically reacting with titanium tetrachloride in the presence of alkylbenzene, and an organoaluminum compound and an organosilicon compound. A catalyst for polymerizing olefins has been proposed, and a method for polymerizing an olefin in the presence of the catalyst is exemplified.

[0006]

The above-mentioned respective prior arts are catalysts having such a high activity that their purpose is to omit a so-called deashing step of removing catalyst residues such as chlorine and titanium remaining in the produced polymer. It started with the development of the components, and also focused on improving the yield of the stereoregular polymer and enhancing the sustainability of the catalytic activity during polymerization, and each has produced excellent results.

Recently, however, it has been obtained by a polymerization reaction using an olefin polymerization catalyst comprising such a highly active catalyst component, an organoaluminum compound and an electron donating compound represented by a silicon compound as a third component. The obtained polymer is obtained by a polymerization reaction using a catalyst for olefin polymerization in which a conventional titanium trichloride-type catalyst component is combined with an organoaluminum compound and an electron-donating compound which is a third component optionally used. It has been pointed out that the molecular weight distribution is narrower than that of the polymer, and as a result, there remains a problem that the use thereof is limited to some extent such as impairing the moldability of the final product polyolefin.

As one of means for solving such a problem,
Various attempts have been made, for example, by adopting a multistage polymerization method to obtain a polymer having a wide molecular weight distribution. However, the multi-stage polymerization method is not preferable in terms of cost, such as performing complicated polymerization operations in duplicate and collecting the chelating agent used during polymerization.

Therefore, in JP-A-3-7703,
Presence of a catalyst for olefin polymerization formed from a solid titanium catalyst component containing magnesium, titanium, halogen and an electron donor as essential components, an organoaluminum compound and at least two or more electron donors (organosilicon compounds) Below, methods of polymerizing olefins have been proposed.

According to the above-mentioned polymerization method, the complicated multi-step polymerization method is omitted, and it is said that a desired polymer having a wide molecular weight distribution can be obtained. However, electron donation at the time of polymerization of two or more kinds of organosilicon compounds. Further improvement has been desired in terms of complexity of processing operations, such as use as a body being an essential requirement.

The present inventors have made it possible to obtain a polymer having a broad molecular weight distribution while maintaining a desired high polymerization activity and a stereoregular polymer yield with a simpler operation. As a result of various studies aimed at developing the above-mentioned polymerization method, it was found that such a problem can be solved by using a specific organosilicon compound as a catalyst component for olefin polymerization, and the present invention has been completed.

[0012]

Means for Solving the Problems That is, the present invention provides (A)
To a suspension formed of (a) dialkoxymagnesium and (b) an aromatic hydrocarbon that is liquid at room temperature, (c) titanium tetrachloride having a volume ratio to the aromatic hydrocarbon of 1/2 or less is added. After that, the temperature is raised and (d) a diester of phthalic acid is added, and the solid substance obtained by further raising the temperature and reacting in a temperature range of 80 to 130 ° C. is washed with an aromatic hydrocarbon, and further (b) ) Obtained by adding (c) titanium tetrachloride in a volume ratio to the aromatic hydrocarbon of 1/2 or less in the presence of an aromatic hydrocarbon that is liquid at room temperature and reacting in the temperature range of 80 to 130 ° C. Solid catalyst component (B) Organoaluminum compound and (C) General formula Si (C ₆ H ₁₁ ) ₂ (OR) ₂ (wherein C ₆ H ₁₁
Is a cyclohexyl group, and R is an alkyl group having 1 to 5 carbon atoms. The present invention provides an olefin polymerization catalyst characterized by comprising an organosilicon compound represented by the formula (4), and an olefin polymerization method characterized by carrying out olefin polymerization in the presence of the catalyst.

Examples of the (a) dialkoxymagnesium (hereinafter sometimes simply referred to as the (a) substance) used in the present invention include diethoxymagnesium, di-n-butoxymagnesium, diphenoxymagnesium and di-.
Examples thereof include n-propoxymagnesium, di-sec-butoxymagnesium, di-tert-butoxymagnesium, diisopropoxymagnesium, and among them, diethoxymagnesium is preferable.

Examples of the aromatic hydrocarbon (b) which is liquid at room temperature (hereinafter sometimes simply referred to as (b) substance) used in the present invention include benzene, toluene, xylene, ethylbenzene, propylbenzene, trimethylbenzene and the like. can give.

The phthalic acid diester (d) used in the present invention (hereinafter sometimes simply referred to as (d) substance) is dimethyl phthalate, diethyl phthalate, diisopropyl phthalate, di-n-propyl phthalate, di-n. -Butyl phthalate, diisobutyl phthalate, diamyl phthalate, diisoamyl phthalate, ethyl-n-butyl phthalate, ethyl isobutyl phthalate, ethyl propyl phthalate and the like.

Examples of the organoaluminum compound (B) used for forming the catalyst in the present invention include trialkylaluminum, dialkylaluminum halide, alkylaluminum dihalide and mixtures thereof.

[0017] The used in the catalyst formation of the present invention (C) the general formula _{Si (C 6 H 11) 2} (OR) 2 ( wherein C ₆ H ₁₁
Is a cyclohexyl group, and R is an alkyl group having 1 to 5 carbon atoms. Examples of the organosilicon compound represented by) include dicyclohexyldimethoxysilane, dicyclohexyldiethoxysilane, dicyclohexyldipropoxysilane, and dicyclohexyldibutoxysilane.

Next, the method for preparing the solid catalyst component (A) of the present invention will be described.

First, the respective components may be used in any ratios so long as the substances (a) and (b) can form a suspension, and (c) titanium tetrachloride (hereinafter simply referred to as ( c)
(Sometimes referred to as a substance) is 1.0 g or more for 1.0 g of the substance (a), and is 1 / the volume ratio to the substance (b).
It is 2 or less. In addition, (d) substance is (a) substance 1.0 g
On the other hand, it is used in the range of 0.1 to 1.0 g.

The suspension of the substances (a) and (b) is usually formed by stirring at room temperature to a temperature not higher than the boiling point of the substance (b) for 100 hours or less, preferably 10 hours or less. At this time, it is necessary to take care so that the suspension does not become a uniform solution.

The contact between the suspension and the substance (c) is usually carried out in the vicinity of room temperature, preferably in the temperature range of 5 to 20 ° C. Further, the contact with the substance (d) is performed in a temperature range of 5 to 110 ° C.,
Thereafter, the temperature is raised and the reaction is performed while stirring in the temperature range of 80 to 130 ° C. for 10 minutes to 10 hours.

The solid substance obtained after the completion of the reaction is washed with an aromatic hydrocarbon, and the aromatic hydrocarbon may be the same as or different from the substance (b).

After completion of washing, the solid substance is further added with a substance (c) having a volume ratio to the substance (b) of 1/2 or less in the presence of the substance (b), and the mixture is heated in a temperature range of 80 to 130 ° C. for 10 minutes. ~
The solid catalyst component (A) is prepared by reacting with stirring for 10 hours.

The solid catalyst component (A) is washed with an inert organic solvent such as n-heptane and then left as it is or dried to form the olefin polymerization catalyst of the present invention.

The solid catalyst component (component A) thus prepared is the above-mentioned organoaluminum compound (component B).
And the above general formula Si (C ₆ H ₁₁ ) ₂ (OR) ₂ (wherein C ₆ H
₁₁ is a cyclohexyl group, and R is an alkyl group having 1 to 5 carbon atoms. ) And an organosilicon compound (component C) represented by the formula (1) to form the olefin polymerization catalyst of the present invention.

The amounts of these components used are such that the organoaluminum compound (component B) is 5 to 1000 and the organosilicon compound (component C) is the molar ratio per mole of titanium atoms in the solid catalyst component (component A). The molar ratio of the organoaluminum compound (component B) is in the range of 0.002 to 0.5.

The polymerization can be carried out in the presence or absence of an organic solvent, and the olefin monomer can be used in a gas or liquid state. The polymerization temperature is 200 ° C or lower, preferably 100 ° C or lower, and the polymerization pressure is 100 ° C.
Kg / cm ² · G or less, preferably 50 Kg / cm ² · G
It is below.

The olefins homopolymerized or copolymerized by the method of the present invention include ethylene, propylene, 1-butene,
4-methyl-1-pentene and the like.

[0029]

According to the olefin polymerization catalyst of the present invention and the polymerization method using the catalyst, a polyolefin having a wide molecular weight distribution and excellent stereoregularity can be obtained in a high yield. became. It is presumed that such an action is caused by a special organosilicon compound used at the time of catalyst formation.

[0030]

EXAMPLES AND COMPARATIVE EXAMPLES The present invention will be described in more detail with reference to Examples and Comparative Examples.

<Example 1><Preparation of solid catalyst component> 10 g of diethoxymagnesium and 80 ml of toluene were charged into a round bottom flask having a capacity of 500 ml, which was sufficiently replaced with nitrogen gas and equipped with a stirrer. And then add TiCl ₄ 20 to this suspension.
After adding ml, the temperature was raised to 90 ° C., 2.7 ml of di-n-butyl phthalate was added, and the temperature was further raised to 115 ° C. to 2
The reaction was carried out with stirring for an hour. After completion of the reaction, it was washed twice with 100 ml of toluene at 90 ° C., and 20 m of TiCl ₄ was newly added.
1 and 80 ml of toluene were added and the temperature was raised to 115 ° C.
The reaction was carried out with stirring for an hour. After completion of the reaction, n at 40 ° C
Washed with 100 ml of heptane 10 times to give a solid catalyst component. The solid content of the solid catalyst component was separated and the titanium content of the solid content was measured to be 2.61% by weight.

<Formation and Polymerization of Polymerization Catalyst> Triethylaluminum (1.32 mmol) was placed in an autoclave equipped with a stirrer and having an internal volume of 2.0 l, which was completely replaced with nitrogen gas.
0.13 mmol of dicyclohexyldimethoxysilane and 0.0066 mmo of the solid catalyst component as Ti
1 was charged to form a polymerization catalyst. After that, hydrogen gas 1.
Charge 8 liters and 1.4 liters of liquefied propylene, 30 at 70 ℃
A polymerization reaction was carried out for a minute. After the completion of the polymerization reaction, the weight of the produced polymer is defined as (A). This product was extracted with boiling n-heptane for 6 hours to obtain a polymer insoluble in n-heptane, and the weight of this product is designated as (B).

The polymerization activity (C) per solid catalyst component used is represented by the following formula.

[Equation 1]

The yield (D) of all crystalline polymer is represented by the following formula.

[Equation 2]

Further, MI of the produced polymer is represented by (E) and molecular weight distribution is represented by (F), and the obtained results are shown in Table 1.

Example 2 An experiment was conducted in the same manner as in Example 1 except that 60 ml of toluene and 40 ml of TiCl ₄ were used when the solid catalyst component was prepared.

The solid content of the solid catalyst component at this time was separated and the titanium content of the solid content was measured to be 2.69% by weight.
Met. The results obtained are shown in Table 1.

Example 3 An experiment was conducted in the same manner as in Example 1 except that the amount of di-n-butyl phthalate used in preparing the solid catalyst component was changed to 2.4 ml of di-n-propyl phthalate.

At this time, the solid-liquid in the solid catalyst component was separated and the titanium content of the solid was measured to be 2.74% by weight.
Met. The results obtained are shown in Table 1.

Comparative Example 1 An experiment was conducted in the same manner as in Example 1 except that phenyltriethoxysilane was used instead of dicyclohexyldimethoxysilane used when forming the polymerization catalyst. The obtained results are as shown in Table 1, but the molecular weight distribution was narrower than that of each example.

An experiment was conducted in the same manner as in Example 1 except that cyclohexylmethyldimethoxysilane was used in place of the dicyclohexyldimethoxysilane used for forming the polymerization catalyst, and the amount of hydrogen gas charged during the polymerization was 3.0 liters. .. The obtained results are as shown in Table 1, but as in Comparative Example 1, no broadening of the molecular weight distribution was observed.

[0042]

As shown in Table 1, the molecular weight distribution of the polymer obtained by the present invention is clearly improved as compared with the molecular weight distribution of the polymer obtained by the conventionally known method. Can be applied to a wide range of applications.

Further, since the polymerization activity per catalyst component and the yield of the stereoregular polymer are maintained at a high level, it can be expected to have extremely high industrial practicality.

Further, in the method of polymerizing an olefin in the presence of a highly active catalyst of this kind, a multi-stage polymerization method or a method of using two or more kinds of organosilicon compounds at the time of polymerization is not used, but a special organosilicon compound is used. The feature of the present invention lies in that such an effect is achieved by the obtained catalyst and the polymerization method using the catalyst.

[Table 1]

[Brief description of drawings]

FIG. 1 is a schematic flowchart illustrating the configuration of the present invention.

Claims (2)

[Claims] 1. A suspension comprising (A) (a) dialkoxymagnesium and (b) an aromatic hydrocarbon which is liquid at room temperature, has a volume ratio to the aromatic hydrocarbon of 1/2 or less. A solid substance obtained by adding (c) titanium tetrachloride and (d) a diester of phthalic acid and then heating the mixture to react in a temperature range of 80 to 130 ° C. is washed with an aromatic hydrocarbon, and further (b) ) Obtained by adding (C) titanium tetrachloride in a volume ratio to the aromatic hydrocarbon of 1/2 or less in the presence of an aromatic hydrocarbon that is liquid at room temperature, and reacting in a temperature range of 80 to 130 ° C. Solid catalyst component (B) Organoaluminum compound and (C) General formula Si (C ₆ H ₁₁ ) ₂ (OR) ₂ (wherein C ₆ H ₁₁
Is a cyclohexyl group, and R is an alkyl group having 1 to 5 carbon atoms. ) A catalyst for olefin polymerization, which comprises an organosilicon compound represented by 2. A suspension formed by (A) (a) dialkoxymagnesium and (b) an aromatic hydrocarbon which is liquid at room temperature has a volume ratio to the aromatic hydrocarbon of 1/2 or less. A solid substance obtained by adding (c) titanium tetrachloride and (d) a diester of phthalic acid and then heating the mixture to react in a temperature range of 80 to 130 ° C. is washed with an aromatic hydrocarbon, and further (b) ) Obtained by adding (C) titanium tetrachloride in a volume ratio to the aromatic hydrocarbon of 1/2 or less in the presence of an aromatic hydrocarbon that is liquid at room temperature, and reacting in a temperature range of 80 to 130 ° C. Solid catalyst component (B) Organoaluminum compound and (C) General formula Si (C ₆ H ₁₁ ) ₂ (OR) ₂ (wherein C ₆ H ₁₁
Is a cyclohexyl group, and R is an alkyl group having 1 to 5 carbon atoms. ) Polymerizing an olefin in the presence of a catalyst composed of an organosilicon compound represented by