JPH072792B2 - Method for producing olefin polymer - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing an olefin polymer, and more specifically, it has a narrow particle size distribution, almost no fine powder, and high stereoregularity. The present invention relates to a method capable of producing an olefin polymer having less catalyst residue.

[Prior Art and Its Problems] Conventionally, there is a method for producing an olefin polymer using a Ziegler-Natta type catalyst in which a solid catalyst component in which a titanium component is supported on a magnesium halide carrier and an organoaluminum compound component are combined. Known (Japanese Patent Laid-Open No. 53-39991)
No.

Although this catalyst has a relatively high activity, since magnesium halide remains in the produced polymer, when the olefin polymer obtained by this method is molded and processed, the corrosion of the molding machine is promoted, and the appearance is poor. There is a drawback that a molded product is produced.

On the other hand, a method using a solid catalyst component obtained by supporting magnesium dialkoxide on an oxide carrier such as SiO ₂ which does not contain halogen and then reacting an electron-donating compound with a titanium halide compound has been proposed ( JPA
58-162607).

However, this method cannot be put to practical use because of low catalytic activity and insufficient stereoregularity of the produced polymer.

[Object of the Invention] The present invention has been made based on the above circumstances.

That is, the object of the present invention is to solve the problems in the above-mentioned conventional methods, to have a high activity and a catalyst that lasts for a long time, so that the stereoregularity is high, the catalyst residue is small, and the fine powder is small. It is an object of the present invention to provide a method for producing an olefin polymer that does not hinder transportation, for example.

[Means for Achieving the Object] The gist of the present invention for achieving the object is to provide at least one of SiO ₂ and Al ₂ O ₃ with a fatty acid magnesium and, if necessary, a general formula Mg (OR ¹ ) _t (OR ² ) _2-t [wherein, R ¹ and R ² are an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group, an aryl group or an aralkyl group, and R ¹ and R ² are different from each other. Or they may be the same, and t is a real number from 0 to 2. ] A solid compound (a) supporting a magnesium compound represented by the following formula; an aromatic carboxylic acid ester (b);
TiX ₄ [wherein, X represents a halogen atom. ] The solid catalyst component (A), organoaluminum compound (B), aromatic carboxylic acid ester, and Si-O- obtained by contacting with the titanium halide compound (c) represented by
A method for producing an olefin polymer, which comprises polymerizing an α-olefin in the presence of a catalyst obtained from an electron donor (C) which is at least one selected from the group consisting of organosilicon compounds having a C bond. is there.

The catalyst used in the method of the present invention comprises a specific solid (a)
It is a highly active polymerization catalyst obtained from a specific solid catalyst component (A) in which titanium metal is supported on the specific catalyst carrier and other specific component, which is obtained as follows. be able to. -Regarding Solid Catalyst Component (A) -The solid catalyst component (A) includes a solid substance (a) in which a specific magnesium compound is supported on at least one of SiO ₂ and Al ₂ O ₃ , and an aromatic carboxylic acid ester (b). ) Is contacted with a specific titanium halide compound (c).

The SiO ₂ and Al ₂ O ₃ may be used alone or in combination of both. Below, SiO ₂ and Al
_A component composed of at least one of ₂ O ₃ may be referred to as an inorganic oxide component.

This inorganic oxide component may be used as it is, but it is contacted with a silicon halide, and if necessary, a pretreatment of contacting this inorganic oxide component with the silicon halide and alcohols in this order is performed. It is preferable to use it afterwards. This is because such pretreatment can reduce the amount of poisoning of the carried catalytic metal.

As the silicon halide, those represented by the following general formula can be used.

Si _n H _m XlSi _o R _p X _q (wherein each of l, m, n, o, p, and q is a positive number, and m + l = 2n + 2 and p + q = 2o
+2 is satisfied, R represents an alkyl group or an alkenyl group, and X represents any one of a fluorine atom, a chlorine atom, an iodine atom and an iodine atom. ) Specific examples of the silicon halide include SiCl
₄ , Si ₂ Cl ₆ , Si ₃ Cl ₈ , Si ₄ Cl ₁₀ , SiHCl ₃ , CH ₃ SiCl ₃ , (CH
₃ ) ₂ SiCl ₂ , (CH ₃ ) ₃ SiCl, (CH ₃ ) ₃ SiCl, C ₂ H ₅ SiCl ₃ ,
(C ₂ H ₅ ) ₂ SiCl ₂ , chlorinated compounds such as (C ₂ H ₅ ) ₃ SiCl, fluorinated compounds in which chlorine atoms in the chlorinated compounds are replaced with fluorine atoms, hydrogen atoms, and iodine atoms, and hydrogen fluoride compounds. There are various iodides. Among these, the chlorinated compounds are preferable, and particularly SiCl ₄ , CH ₃ SiCl, (CH ₂ ) ₂ SiCl ₂ , and (C
H ₃ ) ₃ SiCl is preferred.

The amount of silicon halide contacting the inorganic oxide component may be excessive with respect to the inorganic oxide component,
Usually, it is 1 to 100 times mol, preferably 1 to 50 times mol of the group II to IV elements of the periodic table.

The temperature at the time of contact between the inorganic oxide component and the silicon halide is preferably in the range of 0 to 200 ° C. If the temperature at the time of contact is as high as 300 ° C., thermal decomposition of the silicon halide may occur, which is not preferable.

The inorganic oxide component and the silicon halide may be contacted as they are, or may be contacted in a hydrocarbon solvent such as hexane, heptane, benzene, toluene and xylene.

The contact time between the inorganic oxide component and the silicon halide is usually 5 minutes to 24 hours. The contact is preferably performed in an atmosphere of an inert gas such as nitrogen.

After the contact, the inorganic oxide component is preferably washed by decantation. This is because the washing treatment can favorably promote subsequent contact with alcohols if necessary. The above-mentioned hydrocarbon solvent can be used as the washing solvent.

Then, the above-mentioned inorganic oxide component and alcohol after contact with silicon halide are brought into contact with each other, if necessary.

When the above-mentioned inorganic oxide component is brought into contact with alcohols after contacting with a silicon halide, inactivation of the titanium compound to be supported can be prevented, and reduction of titanium effective for polymerization can be prevented.

As the alcohols, monohydric alcohols and polyhydric alcohols can be used.

Examples of the monohydric alcohol include methanol,
Aliphatic saturated alcohols such as ethanol, propanol, isopropanol, butanol, and pentanol; aliphatic unsaturated alcohols such as allyl alcohol and crotyl alcohol; alicyclic alcohols such as cyclopentanol and cyclohexanol; benzyl alcohol and cinnamyl alcohol And the like; heterocyclic alcohols such as furfuryl alcohol; and the like. Examples of the polyhydric alcohols include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, glycerin and the like. Among these, the aliphatic alcohols are preferable, and methanol, ethanol and propanol are particularly preferable.

Further, the amount of the alcohol to be brought into contact with the inorganic oxide component after contacting with the silicon halide is usually 1 to 100 times mol relative to the silicon halide reacted with by contacting with the inorganic oxide component. Good.

The contact between the inorganic oxide component and the alcohol is preferably performed in an inert atmosphere such as nitrogen. The temperature for contacting the inorganic oxide component with the alcohol may be in the range of normal temperature to reflux temperature, but is usually reflux temperature. The contact time is not particularly limited, but is preferably 0.5 to 24 hours under reflux.

After the completion of the reaction by contact, it is preferable to sufficiently wash the inorganic oxide component with the alcohol or the washing solvent.

It is preferable to separate the solid content after the contact between the alcohol and the inorganic oxide component is completed.

If alcohols remain in the solid content, the fatty acid magnesium or magnesium alkoxide added in the next step reacts with the residual alcohols, which adversely affects the catalytic performance. Therefore, it is preferable that the separated solid content is sufficiently dried.

Since such a specific inorganic oxide component serves as a carrier for the catalyst, the specific surface area (BET method) is 10 to 800 m ² / g if the preferred form is defined from the viewpoint of characteristics as a carrier.
Those having an average pore diameter of 10 Å or more and an average particle diameter of 0.1 to 1000 µm are desirable.

The fatty acid magnesium used in the present invention includes magnesium palmitate, magnesium stearate,
Magnesium behenate, magnesium acrylate, magnesium adipate, magnesium acetylenedicarboxylate, magnesium acetoacetate, magnesium azelate, magnesium citrate, magnesium glyoxylate, magnesium glutarate, magnesium crotonic acid, magnesium succinate, magnesium isovalerate,
Magnesium isobutyrate, magnesium octanoate, magnesium valerate, magnesium decanoate, magnesium nonanoate, magnesium docosenoate, magnesium undecenoate, magnesium elaidate, magnesium linolenate, magnesium hexanoate, magnesium heptanoate, magnesium myristate, laurate Magnesium, magnesium butyrate, magnesium oxalate, magnesium tartrate, magnesium suberate, magnesium sebacate, magnesium sorbate, magnesium tetrolate, magnesium hydroacrylate, magnesium pimelate, magnesium pyruvate, magnesium fumarate, magnesium propionate, malein Magnesium acid, magnesium malonaldehyde, magnesium malonate And the like. Among these, saturated fatty acid magnesium is preferable, and magnesium stearate, magnesium octanoate, magnesium decanoate and magnesium laurate are particularly preferable.

In this invention, the solid substance (a) in which the fatty acid magnesium is supported on the inorganic oxide component is used as a catalyst carrier.
In addition to the fatty acid magnesium, a specific magnesium alkoxide compound (hereinafter, both the fatty acid magnesium and the magnesium alkoxide compound may be referred to as a magnesium compound) may be supported.

The specific magnesium alkoxide compound is represented by the general formula: Mg (OR ¹ ) _t (OR ² ) _2-t [wherein, R ¹ and R ² are each an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group, an aryl group]. It is a group or an aralkyl group, R ¹ and R ² may be different from each other or the same, and t is a positive number of 0 to 2. It can be represented by, as such magnesium alkoxide compound, _{e.g., Mg (-OCH 3) 2,} Mg (-OC 2 H 5) 2, M
_{g (-OC 3 H 7) 2} , Mg (-OC 4 H 9) 2, Mg (-OC
_{6 H 13) 2, Mg (} -OC 8 H 17) 2, _{Mg (-OCH 3) (- OC} 2 H 5), And so on.

Among these, dialkoxy magnesium that substitutes an alkoxy group such as a lower alkyloxy group is preferable.

As the method of supporting the fatty acid magnesium and optionally the magnesium alkoxide compound on the surface of the specific inorganic oxide component, the fatty acid magnesium and optionally the magnesium alkoxide compound are previously dissolved or dispersed in an organic solvent, A method of adding the above-mentioned inorganic oxide component and bringing them into contact with each other later may be mentioned.

In these methods, it is preferable for the performance of the catalyst to deposit the magnesium compound on the surface of at least one of the SiO ₂ and Al ₂ O ₃ as uniformly as possible, for that purpose, in an organic solvent capable of dissolving the magnesium compound. Therefore, it is desirable to contact with at least one of SiO ₂ and Al ₂ O ₃ .

Examples of the organic solvent include hydrocarbons such as aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons and halogenated hydrocarbons, and alkoxy such as tetramethoxytitanium, tetraethoxytitanium and tetra-n-butoxytitanium. Titanium, alcohol, ether, aldehyde,
Examples include ketones, carboxylic acids, amines and amides.

As a preferred method of supporting the magnesium compound on the surface of at least one of the SiO ₂ and Al ₂ O ₃ , a solution of the magnesium compound in alkoxytitanium and an aliphatic hydrocarbon and the SiO ₂ and Al ₂ O _{3 are used.} The method of contacting at least one of them in the temperature range of 0 to 300 ° C. for 5 minutes to 24 hours can be mentioned.

The solid substance (a) obtained as described above is used as a carrier for SiO ₂ or Al ₂ O _{3 with} respect to SiO ₂ and A.
When using l ₂ O ₃ together, 0.1 to 20% by weight, particularly 0.5 to 10% by weight, as magnesium atom, based on the total of these
The one containing

Examples of the aromatic carboxylic acid ester (b) which is a raw material of the solid catalyst component (A) include methyl benzoate, methyl benzoate, propyl benzoate, butyl benzoate, octyl benzoate, cyclohexyl benzoate, phenyl benzoate.
Benzyl benzoate, methyl toluate, ethyl toluate, amyl toluate, ethyl benzoate, methyl anisate, ethyl anisate, ethyl ethoxybenzoate,
Aromatic carboxylic acid monoesters such as ethyl p-butoxybenzoate, ethyl o-chlorobenzoate and ethyl naphthoate, dimethyl phthalate, diethyl phthalate,
Dipropyl phthalate, diisobutyl phthalate, methyl ethyl phthalate, methyl propyl phthalate, methyl isobutyl phthalate, ethyl propyl phthalate,
Ethyl isobutyl phthalate, propyl isobutyl phthalate, dimethyl terephthalate, diethyl terephthalate, dipropyl terephthalate, diisobutyl terephthalate, methyl ethyl terephthalate, methyl propyl terephthalate, methyl isobutyl terephthalate,
Ethyl propyl terephthalate, ethyl isobutyl terephthalate, propyl isobutyl terephthalate, dimethyl isophthalate, diethyl isophthalate, dipropyl isophthalate, diisobutyl isophthalate, methyl ethyl isophthalate, methyl propyl isophthalate, methyl isobutyl isophthalate, ethyl propyl isophthalate, ethyl Examples thereof include aromatic carboxylic acid diesters such as isobutyl isophthalate and propyl isobutyl isophthalate.

Of these, alkyl esters of aromatic monocarboxylic acids or aromatic dicarboxylic acids having 1 to 4 carbon atoms are preferable. Particularly preferred are n-butyl benzoate and diisobutyl phthalate.

The specific titanium halide compound, which is one of the raw materials of the solid catalyst component (A), has the general formula TiX ₄ [wherein, X represents a halogen atom. ],
Specifically, TiCl ₄ , TiBr ₄ , TiI _{4 and the} like can be mentioned. These may be used alone or as a mixture of two or more. Of these, it is particularly preferable to use titanium tetrachloride.

The solid catalyst component (A) can be prepared, for example, as follows.

That is, the solid matter (a), the aromatic carboxylic acid ester (b), and the specific titanium halide compound (c) are mixed in an inert solvent such as hexane, heptane, benzene, or toluene at 0 to 200 ° C. , Preferably 10
It can be carried out by contacting at a temperature of ~ 150 ° C for 2 minutes to 24 hours.

The aromatic carboxylic acid ester (b) and / or the titanium halide compound (c) may be allowed to coexist during the preparation of the solid (a). After the reaction with the aromatic carboxylic acid ester (b), the specific titanium halide compound (c) may be contacted.

The solid catalyst component (A) thus prepared preferably contains 0.1 to 10% by weight of titanium atoms, and particularly preferably 0.5 to 6% by weight.

The catalyst in the method of the present invention is at least selected from the group consisting of the solid catalyst component (A), the organoaluminum compound (B), an aromatic carboxylic acid ester and an organosilicon compound having a Si-O-C bond. It is formed from a kind of electron donor (C).

- organic aluminum compound for (B) - Examples of the organoaluminum compound (B), is not particularly limited, the general formula ^{_{AlR 3 v X 3-v Al}} 2 R 3 X 3 [ However, R ³ is 1 to 10 carbon atoms Is an alkyl group, a cycloalkyl group or an aryl group, v is a real number of 1 to 3, and X represents a halogen atom such as chlorine or bromine. ] Are widely used.

Specifically, trialkyl aluminum such as trimethyl aluminum, triethyl aluminum, triisopropyl aluminum, triisobutyl aluminum, trioctyl aluminum and diethyl aluminum monochloride, diisopropyl aluminum monochloride,
Dialkyl aluminum monohalides such as diisobutyl aluminum monochloride and dioctyl aluminum monochloride, alkyl aluminum sesquihalides such as ethyl aluminum sesquichloride are preferable, and a mixture thereof is also preferable.

-Regarding Electron Donor (C) -As the aromatic carboxylic acid ester that can be adopted as the electron donor (C), various aromatic carboxylic acid esters exemplified as the raw material of the solid catalyst component (A) can be used. It can be used preferably. The same applies to the preferred aromatic carboxylic acid ester.

Examples of the organosilicon compound having a Si—O—C bond include alkoxysilane and aryloxysilane. Such examples include the general formula R ⁴ _w Si (OR ⁵ ) _4-w [wherein R ⁴ represents an alkyl group, a cycloalkyl group, an aryl group, an alkenyl group, a haloalkyl group, an aminoalkyl group or halogen. , R ⁵ represents an alkyl group, a cycloalkyl group, an aryl group, an alkenyl group or an alkoxyalkyl group. Further, w is 0 ≦ w ≦ 3. However,
The w R ⁴ and the (4-w) OR ⁵ may be the same or different. ] The silicate ester represented by these can be mentioned. Other examples include siloxanes having an OR ⁵ group or silyl esters of carboxylic acids. Furthermore, as another example, a silicon compound having no Si-O-C bond and a compound having an O-C bond are pre-reacted or reacted during the polymerization of an α-olefin to have a Si-O-C bond. The one converted into an organosilicon compound can be given, for example,
It is possible to use SiCl ₄ and alcohol together.

Specific examples of the organosilicon compound having the Si-O-C bond include trimethylmethoxysilane, trimethylethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, diphenyldimethoxysilane, methylphenyldimethoxysilane, diphenyldiethoxysilane. , Ethyltrimethoxysilane, vinyltrimethoxysilane, methyltrimethoxysilane, phenyltrimethoxysilane, r-chloropropyltrimethoxysilane, methyltriethoxysilane, ethyltriethoxysilane, vinyltriethoxysilane, butyltriethoxysilane, phenyl Triethoxysilane, r-aminopropyltriethoxysilane, chlorotriethoxysilane,
Ethyltriisopropoxysilane, vinyltributoxysilane, ethyl silicate, butyl silicate, trimethylphenoxysilane, methyltriaryloxysilane, vinyltris (β-methoxyethoxy) silane, vinyltriacetoxysilane, dimethyltetraethoxydisiloxane, etc. is there.

The aromatic carboxylic acid ester used as the electron donor (C) may be the same as or different from the aromatic carboxylic acid ester (b) used in the preparation of the solid catalyst component (A).

—Catalyst Component Composition— As the composition of each component of the catalyst for olefin polymerization, the organoaluminum compound (B) is usually 1 to 1000, preferably 5 to 500 in terms of aluminum / titanium atomic ratio, Regarding the electron donor (C), the electron donor (C) / organoaluminum compound (B) (molar ratio) is used.
It is 0.01 to 10, preferably 0.02 to 2.

—Polymerization— The method of the present invention produces an olefin polymer by polymerizing an α-olefin in the presence of the catalyst.

The α-olefin has the general formula R ⁶ —CH═CH ₂ [wherein R ⁶ represents hydrogen or an alkyl group having 1 to 20 carbon atoms or a cycloalkyl group]. ],
Examples thereof include linear monoolefins such as ethylene, propylene, butene-1, pentene-1, and octene-1, branched monoolefins such as 4-methyl-pentene-1, and vinylcyclohexene.

The α-olefin used for the polymerization is not limited to a single type, and a plurality of types of α-olefins may be copolymerized to produce a random copolymer or a block copolymer.

In the copolymerization, unsaturated compounds such as conjugated dienes and non-conjugated dienes can also be copolymerized.

For the polymerization reaction in the method of the present invention, the methods and conditions conventionally used in the field of olefin polymerization technology can be employed.

As a polymerization method, a slurry polymerization method, a bulk polymerization method, a gas phase polymerization method or the like can be adopted.

The polymerization temperature at that time is in the range of 20 to 100 ° C., preferably 40 to 90 ° C., and the polymerization pressure is usually in the range of 1 to 100 Kg / cm ² G, preferably 5 to 50 Kg / cm ² G.

The polymerization reaction can be generally carried out by a solvent polymerization method using an aliphatic, alicyclic, aromatic hydrocarbon or a mixture thereof as a solvent, and the solvent is, for example, propane, butane, pentane, hexane, heptane, cyclohexane. , Benzene, and the like, and mixtures thereof can be used. Further, a vapor phase polymerization method or a bulk polymerization method using a liquid monomer itself as a solvent can be applied.

The molecular weight of the olefin polymer produced in the method of the present invention varies depending on the reaction mode, catalyst system and polymerization conditions, but can be controlled by addition of, for example, hydrogen, alkyl halide, dialkyl zinc or the like, if necessary.

EFFECTS OF THE INVENTION According to the present invention, (1) a catalyst having a high catalytic activity and a long activity duration is used, so that a stable polymerization reaction can be achieved even when performing multi-stage polymerization. (2) Almost no catalyst residue remains in the produced olefin polymer, the olefin polymer can be favorably molded, and (3) an olefin polymer having high stereoregularity can be produced. (4) There is almost no polymer fine powder of 100 μm or less in the produced olefin polymer, and the olefin polymer can be transported in powder form without causing clogging in the pipe. It is possible to provide a useful method for producing an olefin polymer having various advantages.

EXAMPLES Next, the present invention will be described more specifically by showing Examples and Comparative Examples of the present invention.

(Example 1) Preparation of solid catalyst component Calcined silicon oxide (Fuji Davison, grade 95)
2, a specific surface area of 350 meters ² / g, average particle size 54～65Myuemu) dried with magnesium stearate 10.0 g (20 mmol), diethoxy magnesium (30 mmol), kerosene including tetra -n- butoxytitanium (30 mmol) solution 50ml Was added and the mixture was contacted at 150 ° C. for 1 hour. Thereafter, 50 ml of isopropanol was added dropwise, the mixture was stirred at 80 ° C. for 1 hour, decantation was repeated 3 times with 100 ml of n-heptane, and dried under reduced pressure at 80 ° C. for 1 hour to obtain a white catalyst carrier. 3.8 in this catalyst carrier
It contained magnesium atoms by weight.

8.0 g of the catalyst carrier thus obtained was placed in a glass container of 0.5, and 50 ml of n-heptane and n-butyl benzoate were added.
3.6 mmol and 48 g of titanium tetrachloride were added. 1 of this mixture
Stir under reflux for hours. Then, the supernatant was removed by decantation, and the solid portion obtained was thoroughly washed with hot n-heptane to obtain a solid catalyst component. The catalyst contained 2.9% by weight of Ti.

Polymerization of Propylene 0.006 ml atom of the above solid catalyst component (in terms of titanium atom) suspended in 50 ml of hexane in 1 autoclave substituted with argon, 1.5 mmol of triethylaluminum, p-
0.45 mmol of methyl toluate was added. After depressurizing the inside of the autoclave to remove argon, 310 g of propylene and 0.7 N of hydrogen were charged. After 5 minutes, the temperature was raised to 70 ° C, and polymerization was carried out at 70 ° C for 2 hours. After cooling the autoclave and purging with propylene, the content was taken out and dried under reduced pressure to obtain 18.2 g of polypropylene powder. The bulk density of this powder is 0.37 g / cm
^2. Fine powder of 100 μm or less was 0.1% by weight and had excellent fluidity. The ratio (II) of boiling n-heptane extraction residual polymer of this powder was 96.7%. The amount of chlorine in this polymer analyzed by fluorescent X-ray analysis was 63 ppm.

(Comparative Example 1) The same procedure as in Example 1 was performed except that magnesium stearate was not used and 50 mmol of diethoxymagnesium was used. The powder obtained was 10.9 g and its II was 96.0%. The amount of chlorine in this polymer analyzed by fluorescent X-ray analysis was 110 ppm.

(Example 2) In Example 1, alumina was used instead of silicon oxide [A-11, manufactured by Sumitomo Aluminum Co., Ltd., average particle size 40 to 50 m].
Was performed using. The obtained polypropylene powder is
It was 19.5 g, its bulk density was 0.27 g / cm ² , fine powder of 100 μm or less was 0.9% by weight, and II was 96.7%. The amount of chlorine in this polymer analyzed by fluorescent X-ray analysis was 58 ppm.

(Example 3) Preparation of solid catalyst component In a glass container of 0.5 gas which was replaced with argon, calcined silicon oxide (manufactured by Fuji Davison, grade 952, specific surface area 3)
35 g of 50 m ² / g and an average particle size of 54 to 65 μm) and 175 ml of trimethylchlorosilane were added, reacted for 12 hours with stirring under reflux, and then decanted with n-heptane three times and dried.

The same procedure as in Example 1 was carried out using 10.0 g of the obtained solid matter.

The magnesium compound in the catalyst carrier (solid matter in the solid catalyst component) was 4.0% by weight as a magnesium atom, and the titanium halide compound in the solid catalyst component was 3.2% by weight as a titanium atom.

Polymerization of Propylene It was carried out in the same manner as in Example 1. The polypropylene powder obtained was 146 g, and its bulk density was 0.43 g / cm ³ , 100 μ.
Fine powder of m or less was 0.3% by weight, and II was 96.6%. The amount of chlorine in this polymer analyzed by fluorescent X-ray analysis is 7.1ppm
Met.

(Example 4) In Example 3, 2.0 mmol of diisobutyl phthalate was used instead of n-butyl benzoate, and 0.15 mmol of phenyltriethoxysilane was used instead of methyl p-toluate. The polypropylene powder obtained was 205 g, its bulk density was 0.43 g / cm ³ , fine powder of 100 μm or less was 0.2% by weight, and II was 96.8%. The amount of chlorine in this polymer analyzed by fluorescent X-ray analysis was 5.4 ppm.

(Comparative example 2) It carried out similarly to Example 3 except not using magnesium stearate, and using 50 mmol of diethoxy magnesium. The polypropylene powder obtained is 10
It was 5 g and its II was 96.8%. Also, Keiko X
The amount of chlorine in this polymer analyzed by line analysis was 11.3 ppm.

(Example 5) A kerosene solution containing 10.0 g of the solid product obtained in Example 3 and dried magnesium stearate (50 mmol)
100 ml was added and contact was carried out at 150 ° C. for 1 hour. Then, add 50 ml of silicon tetrachloride, stir at 60 ° C. for 1 hour, then n-
Repeat decantation 3 times with 100 ml of heptane,
It was dried under reduced pressure at 0 ° C. for 1 hour to obtain a white catalyst carrier. The following was performed similarly.

The magnesium compound in the catalyst carrier (solid matter in the solid catalyst component) was 4.0% by weight as a magnesium atom, and the titanium halide compound in the solid catalyst component was 3.0% by weight as a titanium atom.

The obtained polypropylene powder is 130g, its bulk density is 0.40g / cm ³ , fine powder of 100μm or less is 0.2wt%, II
Was 96.5%. The amount of chlorine in this polymer analyzed by fluorescent X-ray analysis was 8.8 ppm.

[Brief description of drawings]

FIG. 1 is a flow chart of the method for producing an olefin polymer of the present invention.

Claims (1)

[Claims] 1. At least one of SiO ₂ and Al ₂ O ₃ has a fatty acid magnesium and, if necessary, a general formula Mg (OR ¹ ) _t (OR ² ) _2-t [wherein R ¹ and R 2 ² is an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group, an aryl group or an aralkyl group, R ¹ and R ² may be different from or the same as each other, and t is a real number from 0 to 2 is there. ] The solid substance (a) carrying the magnesium alkoxide represented by: Aromatic carboxylic acid ester (b)
X ₄ [wherein, X represents a halogen atom. ] The solid catalyst component (A), organoaluminum compound (B), aromatic carboxylic acid ester and Si-O obtained by contacting with the titanium halide compound (c) represented by
A method for producing an olefin polymer, which comprises polymerizing an α-olefin in the presence of a catalyst obtained from an electron donor (C) which is at least one selected from the group consisting of organosilicon compounds having a -C bond. .