JP2595227B2 - Method for polymerizing α-olefin - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for polymerizing α-olefin, and more particularly to a method capable of producing polyα-olefin having excellent stereoregularity with high catalytic activity. More specifically, in a method of polymerizing α-olefin using a highly active α-olefin prepolymerization catalyst having excellent stereoregularity,
The present invention relates to a method capable of achieving higher activation without reducing stereoregularity.

[Background Art] A method for producing a crystalline polyolefin by polymerizing α-olefin such as propylene and 1-butene in the presence of a stereoregular catalyst has been proposed and known in many prior arts. Among these polymerization methods, (a) magnesium,
Polymerization of α-olefin in the presence of a highly active titanium solid catalyst component containing titanium, halogen and an electron donor as essential components, (b) a catalyst formed from an organometallic compound catalyst component, and (c) a catalyst formed from an electron donor catalyst component Many prior arts have also proposed methods of obtaining a highly stereoregular polymer with high catalytic activity by performing the above method. These methods require removal of the catalyst and the amorphous polymer from the polymer after polymerization. It has been adopted on an industrial scale as an excellent polymerization method without any.
However, there is a great demand in the art for streamlining technology, and a highly activated polymerization technology is required.

On the other hand, the present applicant has already disclosed in Japanese Patent Publication No. 57-31726 a titanium catalyst component obtained by treating a magnesium halide compound and a titanium halide compound complex with an organic acid ester and a titanium compound and the first of the periodic table. A method of polymerizing α-olefin in the presence of an organometallic compound of a Group 3 or Group 3 metal has been proposed, and JP-B-56-45403 discloses a method of polymerizing a titanium compound in the presence of a magnesium halide compound / titanium halide compound complex. Of a catalyst comprising a solid catalyst component (A) obtained by reacting an organometallic compound of a Group 1 to 3 metal of the periodic table with an organometallic compound of a Group 1 to 3 metal of the periodic table (B). A method is proposed for polymerizing olefins in the presence. However,
In any of these methods, polymerization activity and stereoregularity are low, and a method of assembling these properties more excellently is required.

[Problems to be Solved by the Invention] The present inventors have recognized that the technology in the field of polymerization of α-olefin is in the above-mentioned situation, and have been proposed (a) magnesium, titanium, halogen and A highly active titanium solid catalyst component having an electron donor as an essential component, (b)
In a method of polymerizing α-olefin in the presence of a catalyst formed from an organometallic compound catalyst component and (c) an electron donor catalyst component, further increasing the activity of the catalyst without reducing stereoregularity. As a result of intensive studies on the methods that can be carried out, specific high-activity titanium solid catalyst component (A), specific organometallic compound catalyst component (B), specific transition metal compound catalyst component (C) and specific organosilicon compound catalyst component Α in the presence of a catalyst formed from (D)
Α obtained by prepolymerizing olefin
The present inventors have found that the above object can be achieved by polymerizing α-olefin in the presence of an olefin prepolymerization catalyst, and reached the present invention.

[Means for Solving the Problems] and [Action] According to the present invention, (A) anhydrous magnesium chloride is treated with 2-ethylhexyl alcohol to form a homogeneous solution, and phthalic anhydride is added and dissolved in the homogeneous solution; The obtained homogeneous solution is added to titanium tetrachloride, phthalic acid diester is further added, and the resulting solid part is obtained by reacting titanium tetrachloride.Magnesium, titanium, chlorine and phthalic acid diester are essential components. A highly active titanium solid catalyst component, (B) an organoaluminum compound catalyst component, (C) a titanium tetrachloride catalyst component, and (D) a formula RnSi (OR ¹ ) _4-n (where 0 ≦ n ≦ 3, R and R ¹ each independently represent an alkyl group, a cycloalkyl group, an aryl group or an alkenyl group, provided that the n R, be the same or different (4-n) pieces of oR ¹ group ), A pre-polymerization of α-olefin in the presence of a catalyst formed from a silicon compound catalyst component represented by the following formula, and polymerization of α-olefin in the presence of the resulting α-olefin prepolymerization catalyst. A method for polymerizing α-olefins is provided.

 Hereinafter, the present invention will be described in detail.

In the present invention, the term polymerization may be used to mean not only homopolymerization but also copolymerization, and the term polymer may be used to mean not only homopolymer but also copolymer. .

The titanium catalyst component (A) used in the present invention is a highly active catalyst component containing magnesium, titanium, chlorine and phthalic acid diester as essential components. This titanium catalyst component (A) contains magnesium chloride having small crystallites as compared with commercially available magnesium chloride and usually has a specific surface area of about 3 m.
² / g or more, preferably about 40 to about 1000 m ² / g, more preferably about 80 to about 800 m ² / g, the composition is not substantially changed by hexane washing at room temperature. In the titanium catalyst component (A), chlorine / titanium (atomic ratio) is about 5 to about 200, particularly about 5 to about 1
The electron donor / titanium (molar ratio) described below is about 0.1 to about 10, particularly about 0.2 to about 6, and the magnesium / titanium (atomic ratio) is about 2 to about 100, and about 4 to about 50.
Are preferred. The component (A) may also contain other electron donors, metals, elements, functional groups and the like. It may also contain an organic or inorganic diluent, for example, a silicon compound, aluminum, polyolefin or the like.

Such a titanium catalyst component (A) is obtained by mutual contact of magnesium chloride, a specific electron donor and titanium tetrachloride.

Methods for producing such a titanium catalyst component (A) include, for example, JP-A-50-108385, JP-A-50-126590, and JP-A-50-126590.
Nos. 51-20297, 51-28189, 51-64586, 51-9
No. 2885, No. 51-136625, No. 51-87489, No. 52-10059
No. 6, No. 52-147688, No. 52-104593, No. 53-2580
No. 53-40093, No. 53-43094, No. 55-135102,
No. 56-135103, No. 56-811, No. 56-11908, No. 56-
No. 18606, No. 58-83006, No. 58-138705, No. 58-1387
No. 06, No. 58-138707, No. 58-138708, No. 58-138709
No. 58-138710, No. 58-138715, No. 60-23404
No. 61-21109, No. 61-37802, No. 61-37803,
It can be manufactured according to the method disclosed in each gazette, such as the above-mentioned 55-152710.

Examples of the electron donor that can be a component of the highly active titanium catalyst component (A) of the present invention include oxygen-containing electron donors such as alcohols and esters of organic acids.

More specifically, methanol, ethanol, propanol, pentanol, hexanol, octanol, 2
Alcohols having 1 to 18 carbon atoms such as ethylhexanol, dodecanol, octadecyl alcohol, benzyl alcohol, phenylethyl alcohol, cumyl alcohol, isopropylbenzyl alcohol; dimethyl phthalate, diethyl phthalate, dibutyl phthalate, dioctyl phthalate And organic acid esters having 2 to 30 carbon atoms, including: These electron donors are 2
More than one species can be used.

The electron donor preferably contained in the titanium catalyst component is a diester, and more preferably, dimethyl phthalate, methyl ethyl phthalate, diethyl phthalate, ethyl isobutyl phthalate, ethyl normal butyl phthalate, and dibutyl phthalate. n-propyl, diisopropyl phthalate, di-n-butyl phthalate, diisobutyl phthalate, di-n-heptyl phthalate, di-2-ethylhexyl phthalate, di-n-octyl phthalate, dineopentyl phthalate, didecyl phthalate, phthalate Phthalic acid diester such as benzyl butyl acid, and particularly preferably a diester of phthalic acid and an alcohol having 2 or more carbon atoms.

In the titanium catalyst component, other electron donors may coexist, but if they coexist in an excessively large amount, they have an adverse effect, so they should be suppressed to a small amount.

In the present invention, the magnesium compound used for preparing the solid titanium catalyst component (A) is an anhydrous magnesium chloride compound. The anhydrous magnesium chloride may be derived from a magnesium compound having a reducing ability, or may be derived during preparation of a catalyst component.

In the present invention, the titanium compound used for preparing the solid titanium catalyst component (A) is titanium tetrachloride. Titanium tetrachloride may be used after being diluted with a hydrocarbon, a halogen hydrocarbon or the like.

In the preparation of the titanium catalyst component (A), the amount of titanium tetrachloride, anhydrous magnesium chloride, a specific electron donor, etc. varies depending on the preparation method and cannot be specified unconditionally. Electron donor 0.05-5 mol, titanium tetrachloride 0.05-500
It can be in the order of moles.

When the titanium solid catalyst component (A) contains an electron donor in the method of the present invention, a polymer having particularly excellent stereoregularity can be obtained by the polymerization method of the present invention.

In the present invention, the solid catalyst component (A) as described above
And olefin polymerization or copolymerization using a combination catalyst of an organoaluminum compound catalyst component (B), a catalyst component (C) and a catalyst component (D) described below.

As the organoaluminum compound catalyst component (B),
(I) an organoaluminum compound having at least one Al-carbon bond in the molecule, for example, a general formula R ¹ mAl (OR ² ) nHpXq (where R ¹ and R ² are carbon atoms, usually 1 to 15, preferably 1 to 15, Is a hydrocarbon group containing 1 to 4 and may be the same or different.

X is a halogen, m is 0 ≦ m ≦ 3, n is 0 ≦ n <3, p
Is 0 ≦ p <3, q is a number satisfying 0 ≦ q <3, and m
Organoaluminum compounds represented by + n + p + q = a 3), (ii) the general formula M ¹ AlR ¹ ₄ (wherein M ¹ is Li, Na, K, and the first group of R ¹ is represented by the same) and the Examples thereof include a complex alkylated product of a metal and aluminum.

The following can be exemplified as the organoaluminum compound belonging to the above (i). General formula R ¹ mAl (OR ² ) ₃ -m (where R ¹ and R ² are the same as above. M is preferably 1.5
≦ m <3), a general formula R ¹ AlX ₃ −m (where R ¹ is the same as above; X is a halogen, m is preferably 0 <m <3), a general formula R ¹ AlH _3- m (where R ¹ is the same as above; m is preferably 2 ≦ m <3); and a general formula R ¹ mAl (OR ² ) nXq (where R ¹ and R ² are the same as above. X Is halogen, 0 <
m ≦ 3, 0 ≦ n <3, 0 ≦ q <3, and m + n + q = 3).

In the aluminum compound belonging to (i), more specifically, trialkylaluminum such as triethylaluminum and tributylaluminum, trialkenylaluminum such as triisoprenylaluminum,
Diethylaluminum ethoxide, dialkylaluminum alkoxides such as dibutyl aluminum butoxide, ethyl aluminum sesqui ethoxide, in addition to alkylaluminum sesqui alkoxides such as butyl sesquichloride _{^{butoxide, ▲ R 1 2.5 ▼ Al (}} OR 2) 0.5
Partially alkoxylated alkyl aluminum, diethyl aluminum chloride, dibutyl aluminum chloride, dialkyl aluminum halide such as diethyl aluminum bromide, ethyl aluminum sesquichloride, butyl aluminum sesquichloride, ethyl aluminum sesquichloride having an average composition represented by Alkyl aluminum sesquihalogenides such as bromide, ethyl aluminum dichloride, propyl aluminum dichloride, partially halogenated alkyl aluminum such as alkyl aluminum dihalogenide such as butyl aluminum dibromide, diethyl aluminum hydride, dibutyl aluminum hydride Dialkyl aluminum hydride such as ethyl aluminum dihydride Partially hydrogenated alkylaluminums such as alkylaluminum dihydrides such as propylaluminum dihydride, partially alkoxylated and halogenated alkylaluminums such as ethylaluminum ethoxychloride, butylaluminum butoxycyclolide, ethylaluminum ethoxybromide It is.

As the compound belonging to the above (ii), LiAl (C
_{2 H 5) 4, LiAl (} C 7 H 15) 4 etc. can be exemplified. Among these, it is particularly preferable to use trialkylaluminum, alkylaluminum halide, a mixture thereof and the like.

In the present invention, (A) a highly active titanium solid catalyst component containing magnesium, titanium, chlorine and phthalic acid diester as essential components, (B) an organoaluminum compound catalyst component, and (C) a titanium tetrachloride catalyst component, And (D) an organosilicon compound catalyst component.

The organosilicon compound (D) used as a catalyst component in the present invention generally has a Si--O--C bond, and is, for example, an alkoxysilane or an aryloxysilane. As such an example, the formula RnSi (OR ¹⁾ ₄ -n
(Where 0 ≦ n ≦ 3, R is a hydrocarbon group such as an alkyl group, a cycloalkyl group, an aryl group, an alkenyl group, a haloalkyl group, an aminoalkyl group, or a halogen,
R ¹ is a hydrocarbon group such as an alkyl group, a cycloalkyl group, an aryl group, an alkenyl group, an alkoxyalkyl group and the like, provided that n R and (4-n) OR ¹ groups may be the same or different. )). The above-mentioned organosilicon compound is obtained by previously reacting a compound having no Si—O—C bond with a compound having an OC bond, or by reacting the compound at a polymerization site.
You may convert and use it for the compound which has a -C bond. As such an example, for example, a halogen-containing silane compound or silicon hydride having no Si-OC bond,
Examples thereof include a combination with an alkoxy group-containing aluminum compound, an alkoxy group-containing magnesium compound, and other metal alcoholates, alcohols, formate esters, and ethylene oxide. The organosilicon compound may also contain other metals (eg, aluminum, tin, etc.).

More specifically, trimethylmethoxysilane, trimethylethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, diisopropyldimethoxysilane, t-butylmethyldimethoxysilane, t-butylmethyldiethoxysilane, t-amylmethyldiethoxysilane, Diphenyldimethoxysilane, phenylmethyldimethoxysilane, diphenyldiethoxysilane, bis-o
-Tolyldimethoxysilane, bis-m-tolyldimethoxysilane, bis-p-tolyldimethoxysilane, bis-p-tolyldiethoxysilane, bisethylphenyldimethoxysilane, dicyclohexyldimethoxysilane, cyclohexylmethyldimethoxysilane, cyclohexylmethyldiethoxysilane, ethyl Trimethoxysilane, ethyltriethoxysilane, vinyltrimethoxysilane, methyltrimethoxysilane, n-propyltriethoxysilane, decyltrimethoxysilane, decyltriethoxysilane, phenyltrimethoxysilane, γ-chloropropyltrimethoxysilane, methyl Triethoxysilane, ethyltriethoxysilane, vinyltriethoxysilane,
t-butyltriethoxysilane, n-butyltriethoxysilane, iso-butyltriethoxysilane, phenyltriethoxysilane, γ-aminopropyltriethoxysilane, chlorotriethoxysilane, ethyltriisopropoxysilane, vinyltributoxysilane , Cyclohexyltrimethoxysilane, cyclohexyltriethoxysilane, 2-norbornanetrimethoxysilane, 2-
Norbornanetriethoxysilane, 2-norbornanemethyldimethoxysilane, ethyl silicate, butyl silicate,
Trimethylphenoxysilane, methyltriaryloxysilane, vinyltris (β-methoxyethoxysilane), vinyltriacetoxysilane, dimethyltetraethoxydisiloxane, etc., among which ethyltriethoxysilane and n-propyltriethoxysilane , T-butyltriethoxysilane, vinyltriethoxysilane, phenyltriethoxysilane, vinyltributoxysilane, diphenyldimethoxysilane, phenylmethyldimethoxysilane, bis p-tolyldimethoxysilane, p-tolylmethyldimethoxysilane, dicyclohexyl Dimethoxysilane, cyclohexylmethyldimethoxysilane, 2-nonebornanetriethoxysilane, 2
-Norbornanemethyldimethoxysilane, diphenyldiethoxysilane, ethyl silicate and the like are preferred.

In the polymerization method of the present invention, since the catalyst component (D) is used, a polymer having particularly excellent stereoregularity can be obtained from α-olefin having 3 or more carbon atoms, such as propylene, with higher activity.

The catalyst used in the olefin polymerization method of the present invention,
An α-olefin prepolymerized catalyst obtained by prepolymerizing α-olefin in the presence of a catalyst formed from at least the components (A), (B), (C) and (D). In the method of the present invention, the following method can be exemplified as a method for forming the α-olefin prepolymerization catalyst.

[1] A catalyst is previously formed by contacting the components (A), (B), (C) and (D) in an inert medium, and then by contacting with α-olefin. A method for forming an α-olefin prepolymerization catalyst.

[2] Contacting the components (A), (B), (C) and (D) in the presence of α-olefin, if necessary in an inert medium or in α-olefin medium. To form an α-olefin prepolymerization catalyst.

[3] After the catalyst is formed by bringing the components (A), (B), (C) and (D) into contact with each other, if necessary, in an inert medium or an α-olefin medium In contact with α-olefin, α
-A method for forming an olefin prepolymerization catalyst.

In the method of the present invention, when the catalyst is formed by previously contacting the component (A), the component (B), the component (C) and the component (D) in the absence of α-olefin, Is usually -50 to 100 ° C, preferably -20 to 30 ° C, and the time required for the contact treatment is usually 1 minute to 10 hours, preferably 5 minutes to 2 hours. The contacting is optionally carried out in an inert medium in the absence of the components of α-olefin, and when contacted in the inert medium, the catalyst is formed in suspension. When the catalyst is formed in the form of a suspension, the catalyst suspension can be used as it is for the prepolymerization of α-olefin, and the formed catalyst can be separated from the suspension. Can be used for the prepolymerization of α-olefin.

In the method of the present invention, as described above, α-
Component (A), component (B), (C) in the presence of olefin
By contacting the component and the component (D) in an inert medium or an α-olefin medium as needed, the formation of the catalyst and the formation of the α-olefin prepolymerized catalyst can be performed simultaneously or sequentially. .

In the method of the present invention, the proportions of the components (A), (B), (C) and (D) in the formation of the catalyst or the α-olefin prepolymerization catalyst are as follows. It is. The proportion of the aluminum atom M ₁ of the component (B) to titanium 1 gram atom of the component (A) is usually 1 to 100 gram atoms, preferably in the range of 2 to 30 gram atoms of, (A) a titanium component 1 The ratio of the titanium atom M ₂ of the component (C) to the gram atom is usually in the range of 0.1 to 10 gram atom, preferably 0.4 to 3 gram atom, and the ratio of the component (D) to 1 gram atom of the titanium component (A). The proportion is usually in the range from 0.3 to 30 mol, preferably from 0.7 to 5 mol.

In the process of the present invention, the prepolymerization is carried out in an amount of 0.5 to 500 g, preferably 1 to 100 g, more preferably 2 to 10 g of α per gram of the highly active titanium solid catalyst component (A).
By polymerizing olefins. Examples of the α-olefin used for the prepolymerization include ethylene and α-olefins having 3 to 20 carbon atoms, such as propylene, 1-butene, 4-methyl-1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene, 1-
Tetradecene can be exemplified, but propylene is preferred.

Prepolymerization temperature is -20 ° C to 70 ° C, preferably -10 ° C
To 60 ° C, more preferably 0 ° C to 50 ° C. The time required for the prepolymerization is usually 0.5 to 20 hours,
Preferably, it is 1 to 10 hours.

The prepolymerization can be carried out either in a batch system or a continuous system, and can be carried out under normal pressure or under pressure. In the prepolymerization, a molecular weight regulator such as hydrogen may be present, but the intrinsic viscosity [η] measured in decalin at least at 135 ° C. is 0.2 dl / g or more, preferably 0.2 to 20 dl / g. Should be suppressed to an amount that can be manufactured.

The prepolymerization is carried out without solvent or in an inert medium.
Preliminary polymerization in an inert hydrocarbon medium is preferred from the viewpoint of operability. As the inert hydrocarbon medium used for the prepolymerization, the above-mentioned solvents can be exemplified.

In the prepolymerization, the concentration of the solid catalyst in the prepolymerization reaction system is usually 10 as the concentration of titanium atoms in the solid catalyst.
^-6 to 1 gram atom /, preferably 10 ^-4 to 10 ^-2
In the range of gram atoms /.

In the method of the present invention, the formation of the catalyst or the α
-Inert media that may be used in the formation of the olefin prepolymerization catalyst include ethane, propane, butane, pentane, methylpentane, hexane, heptane,
Octane, decane, gasoline, kerosene, aliphatic hydrocarbons such as gas oil, cyclohexane, alicyclic hydrocarbons such as methylcyclohexane, benzene, toluene, and aromatic hydrocarbons such as xylene can be exemplified, An inert medium consisting of a mixture of two or more of these can also be used. Similarly, examples of the α-olefin medium include α-olefins exemplified as α-olefins for prepolymerization.

In the α-olefin polymerization method of the present invention, the α-olefin prepolymerization catalyst is formed in a suspension state by the above prepolymerization. The suspension can be used as it is, or the catalyst formed from the suspension can be used separately.

The α-olefin prepolymerization catalyst obtained by the above prepolymerization exhibits excellent polymerization activity in the polymerization of α-olefin.

As the olefin used for the polymerization in the method of the present invention, ethylene, propylene, 1-butene, 4-methyl-
Examples thereof include 1-pentene, 1-octene, and the like, which can perform not only homopolymerization but also random copolymerization or block copolymerization. Upon copolymerization, a polyunsaturated compound such as a conjugated diene or a non-conjugated diene can be selected as a copolymerization component. Among these olefins, homopolymerization of propylene, 1-butene or 4-methyl-1-pentene or a mixed component of these olefins and other olefins, mainly containing propylene or 1-butene (for example, 50 moles) %, Preferably 70 mol%) It is preferred to apply the process of the invention to the polymerization or copolymerization of mixed olefins.

In the process according to the invention, the polymerization of the olefins is carried out in the gas phase or in the liquid phase, for example in a slurry. In slurry polymerization, an inert hydrocarbon may be used as a solvent, or olefin itself may be used as a solvent.

In the method of the present invention, the polymerization of α-olefin is carried out in the presence of the α-olefin prepolymerization catalyst. In the polymerization reaction, only the α-olefin prepolymerization catalyst may be used, or in addition to the α-olefin prepolymerization catalyst, any one of the components (B), (C) and (D) may be further used. Components, two or three components can be added.

In the method of the present invention, the ratio of each catalyst component present in the polymerization reaction system is about 0.001 to about 0.5 mg atom / particularly about 0.005 to about 0.5 mg atom in terms of Ti atom for the catalyst component (A). Wherein, for the catalyst component (B), the aluminum atom in the component (B) is about 1 to about 2000 g atoms, preferably about 5 to about 1 g atom of the titanium atom in the catalyst component (A). To about 500 gram atoms, and for the catalyst component (D), one titanium atom in the catalyst component (A).
Component (D) is in the range of about 0.1 to about 500 moles, preferably about 0.5 to 100 moles, per gram atom.

In the polymerization reaction, when the polymerization is carried out by adding the catalyst component (B) in place of the α-olefin prepolymerization catalyst, the ratio of the component (B) is 1 g of titanium atom in the catalyst component (A). The aluminum atoms in component (B) are from about 1 to about 2000 gram atoms, preferably from about 10 to about 500 gram atoms, based on the atom. Similarly, when the polymerization is carried out by adding the catalyst component (D) in addition to the α-olefin prepolymerization catalyst, the additional ratio of the component (D) is based on 1 gram atom of titanium in the catalyst component (A). About 0 to 1000 moles, preferably about 0 to about 10
It is in the range of 0 mol.

The olefin polymerization temperature is preferably from about 20 to about 200
℃, more preferably about 50 to about 180 ℃, the pressure is normal pressure to about 100 kg / cm ² , preferably about 2 to about 50 kg / cm
^It is preferable to carry out under about ² pressure conditions. The polymerization can be performed by any of a batch system, a semi-continuous system, and a continuous system. Further, the polymerization can be carried out in two or more different stages under different reaction conditions.

[Effects of the Invention] In the present invention, a polymer having a high stereoregularity index can be produced with high catalytic efficiency, particularly when applied to stereoregular polymerization of α-olefin having 3 or more carbon atoms.
In connection with the higher activity, the polymer yield per unit solid catalyst component is superior to that of the conventionally proposed one at the level of obtaining a polymer having the same stereoregularity index.
The catalyst residue in the polymer, particularly the chlorine content, can be reduced, and the catalyst removal operation can be omitted, and the rusting tendency of the mold during molding can be significantly suppressed.

Example Next, an example will be described in more detail.

Example 1 [Preparation of solid Ti catalyst component [A]] Anhydrous magnesium chloride 7.14 g (75 mmol), decane 38 ml
And 2-ethylhexyl alcohol 35.1ml (225mmo
l) After heating for 2 hours at 130 ° C to make a homogeneous solution,
1.7 g (11.3 mmol) of phthalic anhydride was added to this solution,
Stir and mix at 130 ° C. for another hour to dissolve phthalic anhydride in the homogeneous solution. After cooling the thus obtained homogeneous solution to room temperature, it is added dropwise over 1 hour to 200 ml (1.8 mol) of titanium tetrachloride kept at -20 ° C. After completion of the charging, the temperature of the mixture was raised to 110 over 4 hours.
The temperature was raised to 110 ° C., and when the temperature reached 110 ° C., 5.03 ml (18.75 mmol) of diisobutyl phthalate was added, and the mixture was kept under stirring at the same temperature for 2 hours. After completion of the reaction for 2 hours, a solid portion was collected by heating, and the solid portion was resuspended in 275 ml of TiCl ₄ , and then heated again at 110 ° C. for 2 hours. After the completion of the reaction, the solid portion is collected again by heating, and sufficiently washed with decane and hexane at 110 ° C. until no free titanium compound is detected in the washing solution. The catalyst component [A] is stored as a hexane slurry in the solid Ti synthesized by the above manufacturing method, and the catalyst slurry concentration is also measured.
A solid Ti catalyst component [A] obtained by drying a part of the composition contained 2.4% by weight of titanium, 56% by weight of chlorine, 19% by weight of magnesium and 13.6% by weight of diisobutyl phthalate.

[Pretreatment of Ti catalyst component [A]] Purified hexane (100 ml), triethylaluminum (1.0 mmol), diphenyldimethoxysilane (2 mmol) in a 400 ml stirrer four-neck glass reactor under a nitrogen atmosphere, and the above solid
After the addition of 2.0 grams of Ti catalyst component [A] and 1 mmol of titanium tetrachloride, propylene was fed to the reactor at a temperature of 20 ° C. at a rate of 3.2 Nl / Hr for 1 hour. When the supply of propylene was completed, the inside of the reactor was replaced with nitrogen, and a washing operation was performed twice, which consisted of removing the supernatant and adding purified hexane, then resuspended in purified hexane and transferred to the catalyst bottle in its entirety. did. At this time, the measurement of the entire volume was also performed, and the slurry concentration of the catalyst was also measured.

[Polymerization] An autoclave having an internal volume of 2 was charged with 750 ml of purified hexane, and 0.75 mmol of triethylaluminum and 0.075 mmol of diphenyldimethoxysilane were added in a propylene atmosphere at 60 ° C.
l and the pretreated product of the catalyst component [A] were 0.0075 mmol in terms of titanium atom (in terms of the catalyst component [A]).
10.9 milligrams). After introducing 200 ml of hydrogen, the temperature was raised to 70 ° C., and propylene polymerization was performed for 2 hours. The pressure during the polymerization was kept at 7 kg / cm ² G.

After completion of the polymerization, the slurry containing the produced polymer was passed through to separate into a white powdery polymer and a liquid phase. The yield of the white powdery polymer after drying was 232.3 g, the extraction residual ratio with boiling n-heptane was 98.5%, MI was 5.1, and the apparent density was 0.44 g.
/ ml. On the other hand, 1.3 g of a solvent-soluble polymer was obtained by concentrating the liquid phase. Therefore, the activity was 17,300 g-pp / g-catalyst, and II in the whole polymer was 98.0.

Comparative Example 1 The same pretreatment operation as in Example 1 was performed, except that 1 mmol of titanium tetrachloride was not added during the pretreatment of the Ti catalyst component [A]. The polymerization was carried out in the same manner as in Example 1. Table 1 shows the polymerization results.

Examples 2 to 5 Preliminary contact was carried out in the same manner as in Example 1 except that the amount of TiCl ₄ added as shown in Table 1 and the solvent used in the preliminary contact were used, and propylene was polymerized. The results are shown in Table 1.

Example 6 Preliminary contact was carried out in the same manner as in Example 1 except that the feed rate and time of propylene during precontact were changed to 8 Nl / Hr and 4 hours, respectively, and propylene was polymerized. . The results are shown in Table 1.

[Brief description of the drawings]

FIG. 1 is a flow chart showing one example of a catalyst preparation method in a polymerization method of α-olefin of the present invention.

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Norio Kashiwa 1-2-9, Murokimachi, Iwakuni-shi (56) References JP-A-61-26604 (JP, A)

Claims (1)

(57) [Claims] (A) Anhydrous magnesium chloride is treated with 2-ethylhexyl alcohol to form a homogeneous solution, phthalic anhydride is added and dissolved in the homogeneous solution, and the obtained homogeneous solution is added to titanium tetrachloride. A highly active titanium solid catalyst component comprising magnesium, titanium, chlorine and phthalic acid diester as essential components, which is obtained by adding an acid diester and reacting titanium tetrachloride with the generated solid part; (B) an organoaluminum compound catalyst Component, (C) a titanium tetrachloride catalyst component, and (D) a formula RnSi (OR ¹ ) _4-n (where 0 ≦ n ≦ 3, R and R ¹ are each independently an alkyl group, a cycloalkyl group , an aryl group or an alkenyl group, provided that n pieces of R, (4-n) pieces of oR ¹ groups may be the same or different.) form a silicon compound catalyst component, represented by Is prepolymerized α- olefin in the presence of a catalyst, resulting in the presence of the resulting α- olefin prepolymerized catalyst, the polymerization method of α- olefin, characterized in that the polymerization of α- olefins.