JPH0725815B2 - Olefin polymerization catalyst component - Google Patents

Description

Description: BACKGROUND OF THE INVENTION The present invention relates to the transition metal components of so-called Ziegler-type catalysts. According to the present invention, it is possible to obtain a catalyst component for olefin polymerization which is highly active and can produce a polymer having a relatively large particle size.

It is conventionally known that a magnesium compound such as magnesium halide, magnesium alkoxide, hydroxymagnesium chloride, dialkyl magnesium, etc. is used as a carrier component to obtain a highly active catalyst.

By the way, when an olefin is polymerized by a Ziegler type catalyst using such a supported catalyst component (solid catalyst component), the olefin polymer produced is obtained in the form of particles. The size distribution depends on the state of particles of the solid catalyst component used. On the other hand, it is desirable that the produced olefin polymer particles have a relatively large particle diameter and that the particle diameters are uniform because it leads to an improvement in the polymer concentration of the produced polymer slurry and an improvement in productivity due to the ease of handling the polymer slurry. .

However, it is difficult to control the particle size of the catalyst component in the above high activity catalyst, and in many cases, the average particle size is 5 to 10
It is about micron and the particle size distribution of the catalyst is wide, which is insufficient.

Therefore, at present, it is desired to develop a method for producing a catalyst, which has a relatively large average particle size of 10 microns or more and whose particle size distribution can be controlled.

Prior Art As prior art, JP-A-49-65999 and JP-A-54-419.
85, JP-A-55-2951, JP-A-55-135102, JP-A-SHO
55-135103, JP-A-56-67311, and the like.

In these prior arts, the Mg compound which is a carrier component is made into fine particles or melted, spray-dried, granulated or rapidly cooled and solidified. In order to increase the catalyst particle size by these methods, as far as the present inventors are aware, there is a problem that a large amount of capital investment is required and that the distribution of the catalyst particles produced is wide.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a solution to the above points, and an object of the present invention is to achieve this object by using an olefin polymerization catalyst component composed of the following components (A) to (B). .

In a solution of the contact product of component (A) magnesium dihalide with titanium tetraalkoxide and / or its polymer, (Wherein R ¹ is a hydrocarbon residue having 1 to 10 carbon atoms) and SiX ₄ (where X is
Is a halogen), and when the solid composition is precipitated by contacting a precipitating compound selected from the group consisting of a halogen, the solution is obtained by stirring the solution at a stirring strength of floating limit stirring strength (nf) or more and 2nf or less. Solid composition.

Component (B) A halogen compound selected from TiX ₄ and SiX ₄ (where X is a halogen).

When the solid catalyst component according to the present invention is used as a transition metal catalyst component of a Ziegler catalyst to polymerize an olefin,
A polymer having a high activity, a relatively large particle size, and a controlled particle size distribution can be obtained.

Although it is not clear why the catalyst component of the present invention can obtain a polymer having high activity and controlled polymer particle properties as described above, stirring conditions during the synthesis of component (A) are one of the important requirements. is there.

DETAILED DESCRIPTION OF THE INVENTION The catalyst component according to the present invention is a contact product of the component (A) and the component (B) prepared in a specific embodiment.

Ingredient (A) Composition Ingredient (A) is a solid composition composed of magnesium dihalide, titanium tetraalkoxide and / or a polymer thereof and a specific polymeric silicon compound.

This solid composition is neither a magnesium dihalide nor a complex of magnesium dihalide with titanium tetraalkoxide and / or its polymer, but another solid. At present, its content has not been sufficiently analyzed, but according to the result of composition analysis, this solid composition contains titanium, magnesium, halogen and silicon.

Preparation Component (A) is prepared by the mutual contact of magnesium dihalide, titanium tetraalkoxide and / or its polymer, and a precipitating compound such as a polymeric silicon compound.

(A) Magnesium dihalide For example, MgF ₂ , MgCl ₂ , MgBr _{2 and the} like.

(B) Titanium tetraalkoxide and its polymer As titanium tetraalkoxide, for example, Ti (OC
_{2 H 5) 4, Ti (} O-isoC 3 H 7) 4, Ti (O-nC 4 H 9) 4, T
_{i (O-nC 3 H 7} ) 4, Ti (O-isoC 4 H 9) 4, Ti [OCH ₂ CH
(CH _{3) 2] 4,} Ti [OC (CH _{3) 3] 4,} Ti (O-nC
_{5 H 11) 4, Ti (} O-nC 6 H 13) 4, Ti (O-nC 7 H 15) 4,
Ti [OCH ₂ CH (C ₂ H ₅ ) C ₄ H ₉ ] _{4 and the} like. Preferred among _{these, Ti (OC 2 H 5)} 4 and _{Ti (O-nC 4 H 9} ) _4.

The polymer of titanium tetraalkoxide is represented by the following formula.

Here, R _{2 to} R ₅ are the same or different hydrocarbon residues, preferably an aliphatic or aromatic hydrocarbon having 1 to 10 carbon atoms, particularly an aliphatic hydrocarbon having 2 to 6 carbon atoms. n is a number of 2 or more, particularly up to 20. It is desirable that the value of n is selected so that the polytitanate ester itself or in the form of a liquid solution can be used in the step of contacting with other components.
Suitable n for handling is 2 to 14, preferably about 2 to 10,
Is. Specific examples of such polytitanate include normal butyl polytitanate (n = 2-1
0), hexyl polytitanate (n = 2 to 10), normal octyl polytitanate (n = 2 to 10), and the like.
Of these, normal butyl polytitanate is preferred.

(C) Precipitating Agent Compound As the precipitating agent, silicon tetrachloride and polymer silicon compounds can be used.

Examples of the polymeric silicon compound include those represented by the following formula.

Here, R ¹ is a hydrocarbon residue having about 1 to 10 carbon atoms, particularly about 1 to 6 carbon atoms.

Specific examples of the polymer silicon compound having such a structural unit include methylhydropolysiloxane, ethylhydropolysiloxane, phenylhydropolysiloxane,
Examples thereof include cyclohexylhydropolysiloxane.

The degree of polymerization thereof is not particularly limited, but those having a viscosity of about 10 centistokes to 100 centistokes are preferable in consideration of handling. Although the terminal structure of the hydropolysiloxane does not have a great influence, it is preferably blocked with an inert group such as a trialkylsilyl group.

In addition to these components, small amounts of alcohols and / or organic acid esters can be used and are also preferred. Specific examples of suitable alcohols and esters are illustrated, for example, in JP-B-54-23394 and JP-A-59-80406.

(D) Contact of Each Component (Amount Ratio) The amount of each component used may be arbitrary as long as the effects of the present invention are recognized, but generally the following range is preferable.

The amount of titanium tetraalkoxide and / or its polymer used is preferably in the range of 0.1 to 10 in terms of molar ratio to magnesium dihalide, preferably in the range of 1 to 4, and more preferably in the range of 2 to 3. Within the range of. The amount ratio of both is preferably such that magnesium dihalide is substantially dissolved in titanium tetraalkoxide and / or its polymer. The amount of the halogenating agent, for example, the polymer silicon compound, used is preferably in the range of 1 × 10 ^{-2 to} 100, preferably in the range of 0.1 to 10, and more preferably 1 in terms of molar ratio with respect to the magnesium dihalide. Within the range of ~ 4.

(Contact Method) The component (A) of the present invention is generally obtained by contacting the above-mentioned three components. The contact of the three components can be performed by any generally known method. Generally, −10
The contact may be performed within the temperature range of 0 ° C to 200 ° C. The contact time is usually about 10 minutes to 20 hours.

Component (A) of the present invention is a solid composition obtained by contacting a liquid contact product of magnesium dihalide with titanium tetraalkoxide and / or a polymer thereof with a precipitating compound such as a polymer silicon compound. The conditions for contacting the polymer silicon compound at that time are important,
The present invention is characterized in that this contact is carried out at a rotation speed of a stirring strength of not less than the floating limit stirring strength (nf) and not more than 2nf of the particles of the solid composition to be precipitated.

Here, the floating limit stirring strength (nf) means the minimum stirring strength in the range where precipitates do not stay in the tank bottom, and in the present invention, a precipitation agent is added to precipitate solid components. The floating limit stirring strength in the state of the final stage of the process is meant.

Normally, the stirring intensity is controlled by the rotation speed of the stirring blade,
The rotation speed of the flotation limit stirring intensity (nf) can be calculated by the following formula (Chemical Engineering 17 , 144 (1953)).

K = coefficient D = tank diameter (m), dp = particle diameter (mm), ρp = particle density (g / cm ³ ), ρc = liquid density (g / cm ³ ), μ = liquid viscosity (centipoise) Vp '= bulk volume of particles Vp = true volume of particles Although conventionally known stirring is usually performed at a rotational speed considerably higher than the above-mentioned nf, the present invention uses nf or more and 2nf or more.
The rotation speed within the range of the rotation speed of the following stirring strength is adopted. Stirring at a rotation speed of around nf is not preferable because the particle size distribution of the particles to be formed generally becomes broad, but it is surprising in the present invention that the particle size distribution does not become broad and sharp. Particles with various distributions can be obtained. The cause is currently under consideration.

The contact of the three components can also be performed in the presence of a dispersion medium. Examples of the dispersion medium in that case include hydrocarbons, halogenated hydrocarbons, dialkyl siloxanes and the like. Specific examples of hydrocarbons include hexane, heptane, toluene,
There are cyclohexane and the like, specific examples of the halogenated hydrocarbon include n-butyl chloride, 1,2-dichloroethylene, carbon tetrachloride, chlorobenzene and the like, and specific examples of the dialkyl polysiloxane include dimethyl polysiloxane and methyl phenyl. Examples thereof include enyl polysiloxane.

Component (B) Component (B) is a halogen compound selected from TiX ₄ and SiX ₄ (where X is a halogen).

Typical compounds include TiCl ₄ , TiBr ₄ , SiCl ₄ , SiBr ₄
Etc.

Production of Catalyst Component The catalyst component of the present invention is a contact product of component (A) and component (B).

Amount Ratio The amount of each component used may be arbitrary as long as the effects of the present invention are recognized, but generally, the following ranges are preferable.

The amount of the component (B) used is preferably in the range of 1 × 10 ^{−3 to} 100, and more preferably in the range of 1 × 10 ⁻² to 10 with respect to the magnesium dihalide constituting the component (A). Is.

Contact Method The catalyst component of the present invention is obtained by contacting the above-mentioned components (A) and (B). The contact may be generally performed within a temperature range of -100 ° C to 200 ° C. The contact time is usually about 10 minutes to 20 hours.

The components (A) and (B) are preferably brought into contact with each other with stirring, or they may be brought into contact by mechanical pulverization using a ball mill, a vibration mill or the like.

The contact between the component (A) and the component (B) can be carried out in the presence of a dispersion medium. The dispersion medium at that time can be selected from those exemplified as those to be used when the component (A) is produced.

Olefin Polymerization Catalyst Formation The catalyst components of the present invention can be used in olefin polymerization in combination with a cocatalyst organometallic compound. Any of the organometallic compounds of metals of Groups I to IV of the Periodic Table known as cocatalysts can be used. In particular,
Organoaluminum compounds are preferred.

Specific examples of the organoaluminum compound include those represented by the following formula. ▲ R ⁶ _3-n ▼ AlXn or ▲ R ⁷ _3-m ▼
Al (OR ⁸ ) m (wherein R ⁶ and R ⁷ may be the same or different and are a hydrocarbon residue or hydrogen having about 1 to 20 carbon atoms, R ⁸ is the above hydrocarbon residue, X is halogen, n and m are numbers of 0n <2 and 0m1, respectively.) Specific examples of such an organoaluminum compound include the following. (A) Trialkylaluminum such as trimethylaluminum, triethylaluminum, triisobutylaluminum, trihexylaluminum, trioctylaluminum, tridecylaluminum, etc., (b)
Alkyl aluminum halides such as diethyl aluminum monochloride, diisobutyl aluminum monochloride, ethyl aluminum sesquichloride and ethyl aluminum dichloride, (c) Dialkyl aluminum hydrides such as diethyl aluminum hydride and diisobutyl aluminum hydride,
(D) Alkyl aluminum alkoxides such as diethyl aluminum ethoxide, diethyl aluminum butoxide and diethyl aluminum phenoxide.

In addition to these organoaluminum compounds (a) to (c), other organometallic compounds such as ▲ R ⁹ _3-a ▼ Al (OR ¹⁰ ) a (1
a3, R ⁹ and R ¹⁰ is a hydrocarbon residue of about the same or different carbon atoms which may be 1-20. It is also possible to use an alkylaluminum alkoxide represented by the formula (1). For example, combination of triethylaluminum and diethylaluminum ethoxide, combination of diethylaluminum monochloride and diethylaluminum ethoxide, combination of ethylaluminum dichloride and ethylaluminum diethoxide, triethylaluminum, diethylaluminum ethoxide and diethylaluminum chloride. It can be used in combination with.

The amount of these organometallic compounds used is not particularly limited,
The weight ratio with respect to the solid catalyst component of the present invention is preferably within the range of 0.5 to 1000.

In order to improve the stereoregularity of an olefin polymer having 3 or more carbon atoms, it is effective to add and coexist an electron donating compound such as an ether, an ester, an amine or a silane compound during the polymerization. The amount of the electron-donating compound used for such a purpose is 0.00 based on 1 mol of the organoaluminum compound.
It is 1 to 2 mol, preferably 0.01 to 1 mol. Specific examples of compounds suitable as such an "external electron donor" include, for example, JP-A-55-127406, JP-A-55-127408 and JP-A-57-57.
63310 and JP-A-56-139511.

Olefin The olefin polymerized by the catalyst system of the present invention has the general formula R-CH
= CH ₂ (wherein R is a hydrocarbon residue having 1 to 10 hydrogen atoms or carbon atoms, and may have a branched group). Is represented by. Specifically, ethylene, propylene,
There are olefins such as butene-1, pentene-1, hexene-1, 4-methylpentene-1. Preferred are ethylene and propylene. In the case of these polymerizations, it is possible to carry out up to 50% by weight, preferably 20% by weight, of the above-mentioned olefins with ethylene, and with propylene up to 30% by weight of the said olefins, especially with ethylene. Can be copolymerized. Copolymerization with other copolymerizable monomers (for example, vinyl acetate, diolefin) can also be performed.

Polymerization The catalyst system of the present invention is applied not only to ordinary slurry polymerization, but also to liquid phase solventless polymerization, solution polymerization, or gas phase polymerization method which uses substantially no solvent. Further, it is also applied to a system in which continuous polymerization, batch polymerization or preliminary polymerization is carried out. As a polymerization solvent in the case of slurry polymerization, a saturated aliphatic or aromatic hydrocarbon such as hexane, heptane, pentane, cyclohexane, benzene, or toluene is used alone or as a mixture. The polymerization temperature is from room temperature to about 200 ° C., preferably 50 ° C. to 150 ° C., and hydrogen can be supplementarily used as a molecular weight regulator at that time.

Experimental Example Example-1 (1) Synthesis of component (A) 20 ml of dehydrated and deoxygenated n-heptane was introduced into a flask having an inner diameter of 10 cm which had been sufficiently replaced with nitrogen, and then introduced.
95 mol of MgCl _{2 and} 0.2 mol of Ti (O-nC ₄ H ₉ ) ₄ were introduced,
The reaction was carried out at 0 ° C for 1 hour. The diameter of the stirring blade used at that time was 6 cm. After completion of the reaction, the temperature was lowered to 40 ° C., 15 ml of methylhydrogenpolysiloxane was introduced, and the reaction was carried out for 3 hours at a stirring rotation speed of 100 rpm.

After completion of the reaction, the produced solid component was washed with n-heptane, a part thereof was taken out, and the average particle size was measured by a sedimentation method.

The rotation speed of the suspension limit stirring strength (nf) of the stirring system in this case was 97 rpm.

(2) Production of catalyst component The above-mentioned component (A) was introduced into a sufficiently purified flask. 50 ml of n-heptane to 4.4 ml of TiCl ₄ (B) and methylhydrogenpolysiloxane 12
Mix the milliliters and introduce into the flask at 30 ° C,
The reaction was carried out at 70 ° C for 2 hours. After completion of the reaction, it was washed with n-heptane to obtain a catalyst component. The Ti content in the catalyst component is
It was 14.1 weight percent.

(3) Polymerization of Ethylene 800 ml of sufficiently dehydrated and deoxygenated n-heptane was introduced into a stainless steel autoclave having an internal volume of 1.5 liter equipped with a stirring and temperature control device, and subsequently 100 mg of triethylaluminum, as described above. 5 mg of the synthesized catalyst component was introduced.

The temperature was raised to 85 ° C., hydrogen was introduced at a partial pressure of 4 kg / cm ² , ethylene was introduced at 5 kg / cm ² , and the total pressure was adjusted to 9 kg / cm ² G. Polymerization was carried out for 3 hours. These conditions were kept constant during the polymerization. After completion of the polymerization, ethylene and hydrogen were purged, the contents were taken out from the autoclave, and the polymer slurry was filtered and dried overnight. 73 grams of polymer were obtained. MFR = 4.4 (g / 10min), polymer bulk specific gravity = 0.45
(G / cc), polymer average particle size = 369 microns.

Example 2 (1) To a flask and purified in the same manner as in Synthesis Example-1 component (A), by introducing n- heptane 40 ml purified similarly, followed similarly MgCl ₂ and Ti as in Example 1 _{(O-nC 4 H 9)} 4 was introduced and reacted in the same manner. The diameter of the stirring blade used at that time was 6 cm. After the reaction was completed, the temperature was lowered to 40 ° C., 30 ml of methylhydrogen polysiloxane was introduced, and the reaction was carried out for 3 hours at a stirring rotation speed of 120 rpm. After completion of the reaction, the produced solid component was washed with n-heptane, a part thereof was taken out, and the average particle size was measured by a sedimentation method.

The rotation speed equivalent to nf was 100 r.p.m.

(2) Production of catalyst component The above component (A) was introduced into a sufficiently purified flask as in Example-1. Ti to 10 ml of n-heptane
11.5 ml of Cl ₄ was mixed, introduced into the flask at 0 ° C./30 minutes, and reacted at 50 ° C. for 2 hours. After the reaction is completed, n
-Washed with heptane to give the catalyst component. Ti in the catalyst component
The content was 10.8 weight percent.

(3) Polymerization of ethylene Under the polymerization conditions of Example-1, triethylaluminum 1 was used instead of 100 mg of triethylaluminum.
00 mg and diethylaluminum chloride 50
Polymerization of ethylene was carried out in exactly the same manner except that milligram was used. 161.5 grams of polymer were obtained. MFR
= 4.5 (g / 10 min), polymer bulk specific gravity = 0.43 (g / cc), and polymer average particle size = 437 microns.

Example-3 (1) Synthesis of component (A) 40 ml of similarly purified n-heptane was introduced into a flask purified in the same manner as in Example-1, and then MgCl ₂ and Ti were mixed in the same manner as in Example-1. (O-nC ₄ H ₉ ) ₄ was introduced,
Further, 0.7 ml of n-BuOH was introduced, and
The reaction was performed in the same manner as in 1. The diameter of the stirring blade at that time was 6 cm.
And the stirring rotation speed was 140 rpm. After the reaction,
It was washed with n-heptane to obtain a component (A). The average particle size of component (A) was 15.9 microns.

The rotation speed equivalent to nf was 100 r.p.m.

(2) Production of catalyst component The component (A) synthesized above was introduced into a sufficiently purified flask. Then add 10 ml of n-heptane to SiCl
₄ 3.2 ml was mixed and introduced into the flask at 30 ° C. for 30 minutes and reacted at 50 ° C. for 2 hours. Then n-heptane 50
Mix 30 ml of TiCl _{4 (} 8.0 ml) with 30 ml.
It was introduced into the flask in minutes and reacted at 50 ° C. for 2 hours. After completion of the reaction, it was washed with n-heptane to obtain a catalyst component. The Ti content in the catalyst component was 5.82 weight percent.

(3) Polymerization of ethylene Polymerization was carried out in exactly the same manner except that the amount of triethylaluminum used was 150 mg under the polymerization conditions of Example-1. 226 grams of polymer were obtained. MFR = 4.7 (g
/ 10 minutes), the bulk density of the polymer was 0.43 (g / cc), and the average particle size of the polymer was 436 microns.

Example-4 (1) Production of catalyst component A component (A) was synthesized in the same manner as in Example-1. Then n-
10 ml of heptane was mixed with 7.1 ml of SiCl ₄ and the mixture was introduced into the flask at 30 ° C. for 1 hour and reacted at 50 ° C. for 2 hours. After completion of the reaction, it was washed with n-heptane to obtain a catalyst component. The Ti content in the catalyst component was 3.81 weight percent.

(2) Polymerization of ethylene Under the polymerization conditions of Example-1, ethylene was polymerized in exactly the same manner except that 200 mg of triisobutylaluminum was used instead of triethylaluminum.

82 grams of polymer were obtained. MFR = 7.1 (g / 10 minutes),
Polymer bulk specific gravity = 0.45 (g / cc), polymer average particle size = 33
It was 1 micron.

Example-5 Polymerization of propylene was carried out using the catalyst component synthesized in Example-2.

A fully dehydrated and deoxygenated n-heptane (500 ml), triethylaluminum (125 mg), diphenyldimethoxysilane (53.6 mg) and Example-2 were synthesized in a stainless steel autoclave having an internal volume of 1.5 liter equipped with a stirring and temperature control device. 15 mg of catalyst component was introduced. Then, 40 ml of H ₂ was introduced, the temperature was raised and the polymerization was carried out under the conditions of polymerization pressure = 5 kg / cm ² G, polymerization temperature = 75 ° C. and polymerization time = 2 hours. After the polymerization was completed, the obtained polymer slurry was separated by filtration and the polymer was dried.

96 grams of polymer were obtained. On the other hand, 5.9
Grams of polymer were obtained. From the boiling heptane extrusion test, the total product II was 86.3 weight percent, MFR = 11.5 (g /
10 minutes), polymer bulk specific gravity = 0.45 (g / cc), and polymer average particle size = 336 microns.

Example-6 Using the apparatus for gas phase polymerization disclosed in Example-1 described in JP-A-57-73011, a sufficiently purified polyethylene powder was charged into the apparatus, and then triethylaluminum 100 was added. Milligram, 10 parts of the catalyst component synthesized in Example-1
Each milligram was introduced. Next, 1.2 kg / cm ^{2 of} H ₂ was introduced, and the introduction of ethylene was started at 85 ° C, and the total pressure was 9 kg / c.
Polymerization was performed at m ² and 85 ° C. for 2.5 hours. 151 grams of polymer were obtained. MFR = 1.8 (g / 10 min), average particle size of polymer = 368 micron.

Comparative Example-1 Production of Catalyst Component In the production of the catalyst component of Example-1, the production was carried out in exactly the same manner except that the stirring rotation speed at the time of contact with methylhydrogenpolysiloxane was 300 rpm. After the reaction,
The produced solid component was washed with n-heptane, a part thereof was taken out, and the average particle size was measured and found to be 8.6 microns. The nf was 97r.pm.

Polymerization of ethylene Polymerization of ethylene was carried out under the same conditions as in Example-1. 78 grams of polymer were obtained. MFR = 4.1 (g / 10
Min), polymer bulk specific gravity = 0.47 (g / cc), and polymer average particle size = 179 microns.

Example-7 (1) Production of component (A) In the production of component (A) of Example-1, MgCl ₂ and Ti
It was carried out in the same manner as (O-nC ₄ H ₉₎ reaction in Example 1 of _4. After the reaction was completed, the temperature was lowered to 10 ° C and the stirring speed was 120r.
0.2 mol of SiCl _{4 was} introduced over 1 hour at pm and reacted at 30 ° C. for 3 hours. After completion of the reaction, it was thoroughly washed with n-heptane. The average particle size was 14.6 microns. Ti content is
It was 3.52 weight percent. Nf (equivalent rotation speed)
Was 98r.pm.

(2) Polymerization of ethylene Polymerization was carried out under the same conditions as in Example-1. The component (A) was used as it was as a catalyst component. Eighty-one grams of polymer were obtained, MFR = 5.6 (g / 10 min), polymer bulk density = 0.40 (g / cc), polymer average particle size = 358 microns.

Example-8 Ethylene-Butene-1 Copolymerization In the polymerization of Example-1, ethylene-butene-1 containing 10% by volume of butene-1 instead of ethylene.
Polymerization was performed in exactly the same manner except that the mixed gas was used and the polymerization temperature was 75 ° C. 101 grams of polymer were obtained, MFR = 6.2 (g / 10 min), polymer bulk specific gravity = 0.43 (g / c
c), polymer average particle size = 401 microns, polymer density =
It was 0.921 (g / cm ³ ).

[Brief description of drawings]

FIG. 1 is intended to help the understanding of the technical content of the present invention regarding the Ziegler catalyst.

Claims (1)

[Claims] 1. A catalyst component for olefin polymerization, which is a contact product of the following components (A) to (B). To the solution of the contact product of component (A) magnesium dihalide with titanium tetraalkoxide and / or its polymer, (Wherein R ¹ is a hydrocarbon residue having 1 to 10 carbon atoms) and SiX ₄ (wherein
X is a halogen), when the solid composition is precipitated by contacting with a precipitating compound selected from the following, the solution is agitated while stirring the solution at a stirring strength of not less than the floating limit stirring strength (nf) and not more than 2nf. The solid composition obtained. Component (B) A halogen compound selected from TiX ₄ and SiX ₄ (where X is a halogen).