JPH037703A - Polymerization of olefin and catalyst for olefin polymerization - Google Patents

Abstract

PURPOSE:To obtain the subject polymer having wide molecular weight distribution in one step and high yield by using a polymerization catalyst composed of a solid Ti catalyst component containing Mg, Ti, halogen and electron donor, an organic Al compound component and a plurality of specific electron donor catalyst components. CONSTITUTION:The objective polymer is produced by (co)polymerizing an olefin in the presence of an olefin polymerization catalyst composed of (A) a solid Ti catalyst component containing Mg, Ti, halogen and an electron donor as essential components, (B) an organic Al compound catalyst component and (C) two or more kinds of electron donor catalyst components containing electron donor (i) and electron donor (ii) satisfying the formula [MFR(a) is the melt flow rate of homopolypropylene produced by using the component (i) together with the components A and B and MFR(b) is that of homopolypropylene produced by using the component (ii) under the same condition as the component (i)].

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to an olefin polymerization method capable of obtaining an olefin polymer with a wide molecular weight distribution in high yield, and an olefin polymerization catalyst used in this polymerization.

Technical background of the invention and its problems There have already been many proposals regarding methods for producing solid catalyst components containing magnesium, titanium, halogen, and electron donors as essential components.
It is also known that a polymer having high stereoregularity can be produced in high yield by using it in the polymerization of the above α-olefin.

Generally, olefin polymers obtained using Mg CΩ2-supported highly active catalyst components are said to have a narrow molecular weight distribution,
Although they have excellent mechanical properties, olefin polymers that are easy to flow when melted and have improved moldability are also desired for some applications.

Therefore, conventional methods have been taken such as using multiple polymerization vessels and producing olefin polymers with different molecular weights in each polymerization vessel to obtain a polymer with a wide molecular weight distribution and improve moldability. Ta. However, the above method cannot be used with a single polymerization vessel, and it is time-consuming to produce an olefin polymer with a wide molecular weight distribution using a multi-stage polymerization vessel. It has been desired to develop a method for producing olefin polymers that can produce a wide variety of olefin polymers.

As a result of repeated studies to obtain an olefin polymer with a wide molecular weight distribution in a single-stage polymerization operation, the present inventor has discovered that by using at least two or more specific electron donors, an olefin (co)polymer with a wide molecular weight distribution can be obtained. The present invention was completed based on the knowledge that it is possible to obtain the following.

Purpose of the Invention The present invention aims to solve the problems associated with the prior art as described above, and aims to develop an olefin polymer that can produce an olefin polymer with a wide molecular weight distribution in a single stage polymerization operation. The object of the present invention is to provide a polymerization method and an olefin polymerization catalyst used in the polymerization.

Summary of the Invention The olefin polymerization method according to the present invention comprises: [A] a solid titanium catalyst component containing magnesium, titanium, halogen, and an electron donor as essential components; [B] an organoaluminum compound catalyst component; and [C]
At least two or more types of electron donor catalyst components containing an electron donor (a) and an electron donor (b), (wherein the electron donor (a) is combined with the solid titanium catalyst component [A] and an organoaluminum compound) MFR (a) of homopolypropylene obtained using the catalyst component [B] and MFR of homopolypropylene obtained using the above electron donor (b) under the same polymerization conditions as co-1j body (a) (b)
and log [MFR(b)/MFR(a)] ≧1.
5) is characterized by polymerizing or copolymerizing an olefin.

The catalyst for olefin polymerization according to the present invention comprises: [A] a solid titanium catalyst component containing magnesium, titanium, halogen, and an electron donor as essential components; [B] an organoaluminum compound catalyst component; and [C]
At least two or more types of electron donor catalyst components containing an electron donor (a) and an electron donor (b), (wherein the electron donor (a) is combined with the solid titanium catalyst component [A] and an organoaluminum compound) MFR (a) of homopolypropylene obtained using the catalyst component [B] and MFR (b) of homopolypropylene obtained using the above electron donor (b) under the same polymerization conditions as the electron donor (a) is formed from og [VFR(b)/MFR(a)] ≧1.5).

As described above, the polymerization method of the present invention comprises a solid titanium catalyst component [A], an organoaluminum compound catalyst component [B], and at least two or more specific electron donor catalyst components [C
] Since the catalyst formed from the above is used, an olefin polymer having a wide molecular weight distribution and excellent stereoregularity can be produced in high yield. In addition, the above-mentioned catalyst does not easily reduce the polymerization activity, and when this catalyst is used, it is easy to adjust the melt flow rate of the olefin polymer obtained.

DETAILED DESCRIPTION OF THE INVENTION The olefin polymerization method according to the present invention and the olefin polymerization catalyst used therein will be specifically described below.

In the present invention, the term "polymerization" refers not only to homopolymerization, but also to
It is sometimes used to include copolymerization, and the term polymer is sometimes used to include not only homopolymers but also copolymers.

In the olefin polymerization method according to the present invention, olefin polymerization or copolymerization is carried out in the presence of an olefin polymerization catalyst as described below.

The olefin polymerization catalyst according to the present invention comprises a solid titanium catalyst component [A] and an organoaluminum compound catalyst component [B].
and at least two specific electron donor catalyst components [
C].

FIG. 2 shows an example of a flowchart of the method for preparing the catalyst used in the present invention.

The solid titanium catalyst component [A] used in the present invention is a highly active catalyst component containing magnesium, titanium, halogen, and an electron donor as essential components.

Such a solid titanium catalyst component [A] is prepared by contacting a magnesium compound, a titanium compound, and an electron donor as described below.

In the present invention, the titanium compound used for preparing the solid titanium catalyst component [A] is, for example, Tl(OR).
Examples include tetravalent titanium compounds represented by X (R is a hydrocarbon group, X is a halogen atom, 0≦g≦4). More specifically, TiCf
l ST+ Tetra4 titanium halides such as Br 1Ti I4; Ti(OCH)CΩ3, Ti(QCH)CΩ3, 5Ti(On-Ca H9) Cj! 3, T j (O
CR) Br s, 5 Ti(Oiso CH) Br 3 and other trihalogenated alkoxytitanium nonapides; Ti(OCR) CΩ2, 2 TI(OC2H5)20g2, TI(On-CH) Cjl12, 92 TI(OC2H5)2B Dihalogenated dialkoxytitanium such as 2; monohalogenated such as Ti(OCH3) 3(1°Ti(o C2H5) scΩ, Ti(On-C4H9)3 CΩ, T1(o C2a5 > a Br) Tetraalkoxytitanium such as T i (OCHa) 4, TI (OC2H5) 4, T i (On-Ci, H9) a, and the like can be mentioned.

Among these, halogen-containing titanium compounds, particularly titanium tetrahalide, are preferred, and titanium tetrachloride is more preferred. These titanium compounds may be used alone or in combination of two or more. Furthermore, these titanium compounds may be diluted with a hydrocarbon compound or a halogenated hydrocarbon compound.

In the present invention, the magnesium compound used in the preparation of the solid titanium catalyst component [A] includes a magnesium compound having reducibility and a magnesium compound not having reducibility.

Here, examples of the reducing magnesium compound include magnesium compounds having a magnesium-carbon bond or a magnesium-hydrogen bond. Specific examples of magnesium compounds having such reducing properties include dimethylmagnesium, diethylmagnesium, dipropylmagnesium,
Dibutylmagnesium, cyamylmagnesium, didecylmagnesium, didecylmagnesium, ethylmagnesium chloride, propylmagnesium chloride, butylmagnesium chloride, hexylmagnesium chloride, amylmagnesium chloride, butylethoxymagnesium, ethylbutylmagnesium, butylmagnesium halide, etc. I can do it. These magnesium compounds may be used alone or may form a complex compound with an organoaluminum compound described below. Moreover, these magnesium compounds may be liquid or solid.

Specific examples of non-reducing magnesium compounds include magnesium halides such as magnesium chloride, magnesium bromide, magnesium iodide, and magnesium fluoride; methoxymagnesium chloride, ethoxymagnesium chloride, isopropoxymagnesium chloride, Alkoxymagnesium halides such as butoxymagnesium chloride and octoxymagnesium chloride; alkoxymagnesium halides such as phenoxymagnesium chloride and methylphenoxymagnesium chloride; Examples include alkoxymagnesiums such as soxymagnesium; allyloxymagnesiums such as phenoxymagnesium and dimethylphenoxymagnesium; magnesium carboxylates such as magnesium laurate and magnesium stearate.

These non-reducing magnesium compounds may be compounds derived from the above-mentioned reducing magnesium compounds or compounds derived during the preparation of the catalyst component. In order to derive a non-reducing magnesium compound from a reducing magnesium compound, for example, a reducing magnesium compound can be derived from a polysiloxane compound, a halogen-containing silane compound, a halogen-containing aluminum compound, an ester, an alcohol, etc. It is sufficient if the compound is brought into contact with the compound.

In addition, in the present invention, the magnesium compound includes not only the above-mentioned reducing magnesium compounds and non-reducing magnesium compounds, but also complex compounds, composite compounds, or other metal compounds of the above-mentioned magnesium compounds and other metals. It may be a mixture of. Furthermore, a mixture of two or more of the above compounds may be used.

In the present invention, among these, magnesium compounds that do not have reducing properties are preferred, and halogen-containing magnesium compounds are particularly preferred, and among these, magnesium chloride, alkoxymagnesium chloride,
Allyloxymagnesium chloride is preferably used.

In the present invention, when preparing the solid titanium catalyst component [A], it is preferable to use an electron donor,
Specifically, such electron donors include alcohols, phenols, ketones, aldehydes, carboxylic acids,
Esters, ethers, acid amides of organic or inorganic acids,
Examples include oxygen-containing electron donors such as acid anhydrides, nitrogen-containing electron donors such as ammonia, amines, nitriles, and isocyanate-1.

More specifically, methanol, ethanol, propatool, pentanol, hexanol, octatool, 2-
Alcohols with 1 to 18 carbon atoms such as ethylhexanol, dodecanol, octadecyl alcohol, benzyl alcohol, phenylethyl alcohol, cumyl alcohol, isopropylbenzyl alcohol; phenol;
Cresol, xylenol, ethylphenol, propylphenol, cumylphenol, nonylphenol,
Phenols with 6 to 25 carbon atoms that may have an alkyl group such as naphthol; ketones with 3 to 15 carbon atoms such as acetone, methyl ethyl ketone, methyl isobutyl ketone, acetophenone, and benzophenone; Aldehydes with 2 to 15 carbon atoms such as acetaldehyde, propionaldehyde, octylaldehyde, benzaldehyde, tolualdehyde, naphthaldehyde; methyl formate, ethyl acetate, vinyl acetate, propyl acetate, octyl acetate, cyclohexyl acetate, ethyl propionate, methyl butyrate , ethyl valerate, ethyl stearate, methyl chloroacetate, ethyl dichloroacetate, methyl methacrylate, ethyl crotonate, dibutyl maleate,
Diethyl butylmalonate, diethyl dibutylmalonate,
Ethyl cyclohexanecarboxylate, ■, diethyl 2-cyclohexanedicarboxylate, di2-ethylhexyl 1,2-cyclohexanedicarboxylate, methyl benzoate, ethyl benzoate, propyl benzoate, butyl benzoate, octyl benzoate, cyclohexyl benzoate, Phenyl benzoate, benzyl benzoate, methyl toluate, ethyl toluate, amyl toluate, ethyl ethylbenzoate, methyl anisate, ethyl anisate, ethoxybenzoate 5, ethyl frate, dimethyl phthalate, diethyl phthalate, phthalic acid Organic acid esters having 2 to 30 carbon atoms, including the esters described below, which are preferably contained in the titanium catalyst component such as dibutyl, dioctyl phthalate, γ-butyrolactone, δ-valerolactone, coumarin, phthalide, and ethylene carbonate; silicic acid Inorganic acid esters such as ethyl and butyl silicate; acid halides having 2 to 15 carbon atoms such as acetyl chloride, benzoyl chloride, toluic acid chloride, anisyl chloride, and phthalic acid dichloride; methyl ether, ethyl ether, isopropyl ether, Ethers having 2 to 20 carbon atoms such as butyl ether, amyl ether, tetrahydrofuran, anisole, and diphenyl ether; Acid amides such as acetic acid amide, benzoic acid amide, and toluic acid amide; Acid anhydrides such as benzoic anhydride and phthalic anhydride; Examples include amines such as methylamine, ethylamine, triethylamine, tributylamine, piperidine, tribenzylamine, aniline, pyridine, picoline, and tetramethylethylenediamine; and nitriles such as acetonitrile, benzonitrile, and trinitrile. Further, as an electron donor, an organosilicon compound represented by the following general formula [1F] can also be used.

RS i(OR') 4-n +...[I
][In the formula, R and Ro are hydrocarbon groups, and
4] As the organosilicon compound represented by the above general formula [1], specifically, trimethylmethoxysilane, trimethylethoxysilane, dimethyldimethoxysilane,
Dimethyljethoxysilane, diisopropyldimethoxysilane, t-butylmethyldimethoxysilane, t-butylmethyljethoxysilane, t-amylmethyljethoxysilane, diphenyldimethoxysilane, phenylmethyldimethoxysilane, diphenyljethoxysilane, bis0-) Lyldimethoxysilane, bis-m-tolyldimethoxysilane, bis-p-)lyldimethoxysilane, bis-p
- tolyljethoxysilane, bisethylphenyldimethoxysilane, dicyclohexyldimethoxysilane, cyclohexylmethyldimethoxysilane, cyclohexylmethyljethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, vinyltrimethoxysilane, methyltrimethoxysilane, n-propyltriethoxysilanedecyltrimethoxysilane, decyltriethoxysilanelupropyltrime, I-xysilane, methyltoluethoxysilane, ethyltriethoxysilane, vinyltriethoxysilane, t-butyltriethoxysilane, n-butyltriethoxy Silane, iso-butyltriethoxysilane, phenyltriethoxysilane, γ-aminopropyltriethoxysilane, chlortriethoxysilane, ethyltriisopropoxysilane, vinyltributoxysilane, cyclohexyltrimethoxysilane, cyclohexyltriethoxysilane, 2- Norbornanetrimethoxysilanebornanemethyldimethoxysilane, ethyl silicate, 8 butyl silicate, l-limethylphenoxysilane, methyltriaryloxy (at Iyloxy)silane, vinyl tris (β-meI-xyethoxysilane), vinyl tris Acetoxysilane siloxane, dicyclohexylmethyldimethoxysilane, cyclopentylmethyldimethoxysilane, dicyclopentyldimethoxysilane, dicyclopentyljethoxysilane, di-n-propyljethoxysilane, di-t
-Butyljethoxysilane, cyclopentyltriethoxysilane.

Among them, ethyltriethoxysilane, rutriethoxysilane, t-butyltriethoxysilane, vinyltriethoxysilane, phenyltriethoxysilane, vinyltributoxysilane, diphenyldimethoxysilane, phenylmethyldimethoxysilane, bis p-
Preferred are tolyldume I-xysilane, p-tolylmethyldimethoxysilane, dicyclohexyldimethoxysilane, cyclohexylmethyldimethoxysilane, 2-norbornanetriethoxysilane, 2-norbornanemethyldimethoxysilane, and diphenyljethoxysilane.

Two or more types of these electron donors can be used.

Is it desirable to include titanium in the catalyst component? The b-child donor is an ester, more preferably one represented by the general formula (where R1 is a substituted or unsubstituted hydrocarbon group, R2
R5 R6 is hydrogen or a substituted or unsubstituted hydrocarbon group, RR is hydrogen or a substituted or unsubstituted hydrocarbon group, and preferably at least one of them is a substituted or unsubstituted hydrocarbon group. Also R
3 and R4 may be connected to each other. Above R1~R
Examples of the substituted hydrocarbon group for 5 include those containing different atoms such as N, O, and S, such as C-0-CSCOOR and COOH.

It has groups such as OH, So3H, -C-N-C-NH2. ) can be exemplified.

(2) Particularly preferred among these are diesters of dicarboxylic acids in which at least one of R R2 is an alkyl group having 2 or more carbon atoms.

Specifically, the polyhydric carboxylic acid esters include diethyl succinate, dibutyl succinate, diethyl methyl succinate, diisobutyl α-methylglutarate, dibutyl methyl malonate, diethyl malonate, diethyl ethyl malonate, and diethyl isopropyl malonate. , diethyl butyl malonate, diethyl phenyl malonate, diethyl diethyl malonate, diethyl allyl malonate, diethyl dibutyl malonate, di-n-butyl diethyl malonate, dimethyl maleate, monooctyl maleate, dioctyl maleate, dibutyl maleate, butyl maleate Dibutyl, diethyl butyl maleate, diisopropyl β-methylglutarate, diallyl ethylco-1 succinate, di-2-ethylhexyl fumarate, diethyl itaconate, dibutyl itaconate, dioctyl ci-I malonate, dimethyl ci-I malonate, etc. Aliphatic polycarboxylic acid esters, alicyclic polycarboxylic acid esters such as diethyl 1,2-cyclohexanecarboxylate, diisobutyl 1,2-cyclohexanecarboxylate, diethyl tetrahydrophthalate, diethyl nadic acid, monoethyl phthalate, phthalate Dimethyl acid, methyl ethyl phthalate, monoisobutyl phthalate, mono-normal butyl phthalate, diethyl phthalate, ethyl isobutyl phthalate, ethyl normal-butyl phthalate, di-11-propyl phthalate, diisopropyl phthalate, di-n-butyl phthalate , diisobutyl phthalate, di-n-heptyl phthalate,
Di-2-ethylhexyl phthalate, di-n-octyl phthalate, dineopentyl phthalate, didecyl phthalate, benzylbutyl phthalate, diphenyl phthalate, diethyl naphthalene dicarboxylate, dibutyl naphthalene dicarboxylate, triethyl trimellitate, trimellitic 2 fragrance Examples thereof include group polycarboxylic acid esters, heterocyclic polycarboxylic acid esters such as 3,4-furandicarboxylic acid, and the like.

Further, specific examples of the polyvalent hydroxy compound ester include 1,2-diacetoxybenzene, -methyl-2.
Examples include 3-diacetoxybenzene, 2,3-diacetoxynaphthalene, ethylene glycol dipiparate, butanediol pivalate, and the like.

Specific examples of the hydroxy-substituted carboxylic acid include benzoylethyl salicylate, acetyl isobutyl salicylate, and acetyl methyl salicylate-1.

In addition to the above-mentioned compounds, examples of polyvalent carboxylic acid esters that can be supported in the titanium catalyst component include diethyl adipate, diisobutyl adipate, diisopropyl sebacate, di-n-butyl sebacate, and sebacin. Esters of long chain dicarboxylic acids such as di-n-octyl acid and di-2-ethylhexyl sebacate can be used.

Among these polyfunctional esters, compounds having the skeleton of the above-mentioned general formula are preferred, and esters of phthalic acid, maleic acid, substituted malonic acid, etc. and alcohols having 2 or more carbon atoms are more preferred, with phthalic acid being particularly preferred. Diesters of acids and alcohols having 2 or more carbon atoms are preferred.

Other electron donor components that can be supported on the titanium catalyst component include RCOOR'(RSR' is a hydrocarbyl group that may have a substituent, at least one of which is branched (including alicyclic) ) or a ring-containing chain group). Specifically, together with R and Ro, (CH) CH-C2H3CH(CH3)2 (CH) CHCH2-(CH3)3C2 CHCH(CH3)CH2 5 4 . If either R or Ro is a group as described above, the other may be the group described above, or may be another group, such as a linear or cyclic group.

Specifically, various monoesters such as dimethyl acetic acid, trimethyl acetic acid, α-methylbutyric acid, β-methylbutyric acid, methacrylic acid, and benzoyl acetic acid, various monocarboxylic acids of alcohols such as isopropanol, isobutyl alcohol, and tert-butyl alcohol. Examples include acid esters.

Carbonic esters can also be selected as electron donors. Specifically, diethyl carbonate, ethylene carbonate, diisopropyl carbonate-1., phenylethyl carbonate, diphenyl carbonate-1., etc. can be exemplified.

When supporting these electron donors, it is not necessarily necessary to use them as starting materials, and it is also possible to use compounds that can be converted into these in the process of preparing the titanium catalyst component.

Although other electron donors may coexist in the titanium catalyst component, their coexistence in too large a quantity will have an adverse effect, so they should be kept to a small amount.

In the present invention, the solid titanium catalyst component [A] can be produced by bringing the above-described magnesium compound (or metal magnesium), electron donor, and titanium compound into contact with each other.

In order to produce the solid titanium catalyst component [A], a known method for preparing a highly active titanium catalyst component from a magnesium compound, a titanium compound, and an electron donor can be employed. Note that the above components may be brought into contact with each other in the presence of other reaction agents such as silicon, phosphorus, and aluminum.

Several examples of methods for producing these solid titanium catalyst components [A] will be briefly described below.

(1) A method of reacting a magnesium compound or a complex compound consisting of a magnesium compound and an electron donor with a titanium compound in a liquid phase. This reaction may be carried out in the presence of a grinding aid or the like.

6 Moreover, when reacting as described above, a solid compound may be pulverized.

(2) a liquid magnesium compound that does not have reducing properties;
A method in which a solid titanium complex is precipitated by reacting a liquid titanium compound in the presence of an electron donor.

(3) A method in which the reaction product obtained in (2) is further reacted with a titanium compound.

(4) A method in which the reaction product obtained in (1) or (2) is further reacted with an electron donor and a titanium compound.

(5) A solid material obtained by pulverizing a magnesium compound or a complex compound consisting of a magnesium compound and an electron donor in the presence of a titanium compound is treated with either a halogen, a halogen compound, or an aromatic hydrocarbon. how to. In this method, a magnesium compound or a complex compound consisting of a magnesium compound and an electron donor may be ground in the presence of a grinding aid or the like. Alternatively, a magnesium compound or a complex compound consisting of a magnesium compound and a 7-electron donor may be ground in the presence of a titanium compound, pretreated with a reaction aid, and then treated with a halogen. Note that examples of the reaction aid include organoaluminum compounds and halogen-containing silicon compounds.

(6) A method of treating the compound obtained in the above (1) to (4) with a halogen, a halogen compound, or an aromatic hydrocarbon.

(7) A method in which a contact reaction product of a metal oxide, dihydrocarbylmagnesium, and a halogen-containing alcohol is brought into contact with an electron donor and a titanium compound.

(8) A method in which a magnesium compound such as a magnesium salt of an organic acid, alkoxymagnesium, or aryloxymagnesium is reacted with an electron donor, a titanium compound, and/or a halogen-containing hydrocarbon.

Solid titanium catalyst component [A] listed in (1) to (8) above
Among the preparation methods, a method using liquid titanium halide during catalyst preparation, a method using a titanium compound after use, or a method using a halogenated hydrocarbon when using a titanium compound are preferred.

The amount of each of the above-mentioned components used when preparing the solid titanium catalyst component [A] varies depending on the preparation method and cannot be unconditionally defined, but for example, the amount of electron donor is about 0.01 per mole of magnesium compound. In an amount of ~5 mol, preferably 0.05 to 2 mol, the titanium compound is about 0.0
It is used in an amount of 1 to 500 mol, preferably 0.05 to 300 mol.

The solid titanium catalyst component [A] thus obtained is:
Contains magnesium, titanium, halogen and electron donor as essential components.

In this solid titanium catalyst component [A], the halogen/titanium (atomic ratio) is about 4 to 200, preferably about 5 to 10.
0, and the electron donor/titanium (molar ratio) is about 0.
1 to 10, preferably about 0.2 to about 6, and the magnesium/titanium (atomic ratio) is about 1 to 100, preferably about 2 to 50, preferably 9.

This solid titanium catalyst component [A] contains magnesium halide with a smaller crystal size than commercially available magnesium halides, and usually has a specific surface area of about 50 ry.
e/g or more, preferably about 60 to 1000 e/g,
More preferably about 1.00 to 800 rrf/g. Since the solid titanium catalyst component [A] is composed of the above-mentioned components to form a catalyst component, the composition of the solid titanium catalyst component [A] is not substantially changed by washing with hexane.

Such a solid titanium catalyst component [A] can be used alone, but it can also be used diluted with an inorganic or organic compound such as a silicon compound, an aluminum compound, or a polyolefin. In addition,
When a diluent is used, high catalytic activity is exhibited even if the specific surface area is smaller than the above-mentioned specific surface area.

Regarding the preparation method of such a highly active titanium catalyst component, for example, JP-A-50-108885, JP-A-50-108885;
-128590, No. 51-20297, No. 510-28189, No. 51. -84586 Publication, Publication No. 51-92885, Publication No. 51-188ft25, Publication No. 52-87489, Publication No. 52-100596
No. 52-1471388, No. 52-10
Publication No. 4593, Publication No. 53-2580, Publication No. 53-4
No. 0093, No. 53-40094, No. 53-
No. 43094, No. 55-135102, No. 5
No. 5-135103, No. 55-152710, No. 513-811, No. 5B-11908, No. 5B-1860fi, No. 5g-83008, No. 5B-138705, No. 58 -1387
Publication No. 08, Publication No. 58-138707, Publication No. 58-1
No. 38708, No. 58-138709, No. 5
No. 8-138710, No. 58138715,
It is disclosed in JP 60-23404, JP 61-21109, JP 81-37802, JP 81-37803, etc.

As the organoaluminum compound catalyst component [B], a compound having at least one aluminum-carbon bond in the molecule can be used. Such compounds include, for example, (wherein R1 and R2 are hydrocarbon groups containing usually 1 to 115 carbon atoms, preferably 1 to 4 carbon atoms, and these may be the same or different from each other. X represents a halogen atom, O<m≦3, n is O≦n<3, p is 0≦p
<3, q is a number O≦q<3, and m + n
+ 1) + Q = 3), (ii) general formula MA, l! Examples include complex alkylated products of Group 1 metals and aluminum represented by R'4 (where Ml is Li, Na, or Ni, and R1 is the same as above).

Examples of the organoaluminum compound represented by the formula (i) include the following compounds.

(In the formula, R1 and R2 are the same as above. m is preferably a number of 1.5≦m≦3), general formula R' mAj2
X3-.

(In the formula, R1 is the same as above. is 2≦m<
3), (wherein RI and R2 are the same as above. X is halogen,
0<m≦3.0≦n<3.0≦q<3, m + n
+ q = 3).

More specifically, the aluminum compound represented by (i) includes trialkylaluminum such as triethylaluminum and tributylaluminium; trialkenylaluminum such as triisoprenylaluminum; dialkylaluminum such as diethylaluminum ethoxide and dibutylaluminum butoxide. Alkoxide; alkyl aluminum sesquialkoxide such as ethyl aluminum sesquiethoxide, butyl aluminum sesqui butoxide, partially alkoxylated Al3-kyl having a homogeneous composition of R' Al2 (OR), etc. Aluminum; dialkylaluminum halides such as diethylaluminum chloride, dibutylaluminum chloride, diethylaluminum bromide; alkylaluminum sesquihalides such as ethylaluminum sesquichloride, butylaluminum sesquichloride, ethylaluminum sesquipromide; ethylaluminum dichloride, propylaluminum dichloride, Partially halogenated alkyl aluminum such as alkyl aluminum cybarides such as butyl aluminum dibromide; dialkyl aluminum hydrides such as diethylaluminum hydride, dibutyl aluminum hydride; alkyl aluminum such as ethyl aluminum dicdride, probylaluminum dihydride Other partially hydrogenated alkylaluminums such as dihydrides; mention may be made of partially alkoxylated and halogenated alkylaluminums such as ethylaluminum ethoxy chloride, butylaluminum butoxychloride, ethylaluminum ethoxybromide, etc. .

Compounds similar to (i) include organoaluminum compounds in which two or more aluminum atoms are bonded via oxygen atoms or nitrogen atoms. Examples of such compounds include (C2H5)2AΩOAΩ (C
2H5) 2, (C4H9) 2Aj? OA, 9 (
Examples include C4H9) 2,2H5 methylaluminoxane.

Examples of the compound represented by the formula (it) include Li l
(C2H5), LIA, 17 (C7H15)4, and the like.

Among these, it is particularly preferable to use trialkylaluminum or alkylaluminium in which two or more of the above-mentioned aluminum compounds are combined.

In the present invention, at least two kinds of electron donors including an electron donor (a) and an electron (3% Li form (b)) are used as the electron donor catalyst component [C].

The above electron donor (a) and four electrons fjj (b)
preferably satisfies the following conditions. That is, the electron donor (a) is mixed with the solid titanium catalyst component [A] and the organoaluminum compound catalyst component [A] as described above.
MFR (a) of homopolypropylene obtained when propylene is homopolymerized using the electron donor (b) in combination with the electron donor (b) and propylene using the electron donor (b) under the same polymerization conditions as the electron donor (a). The MFR(b) of homopolypropylene obtained in the case of homopolymerization is l og [MFR(b) /
The electron donor (a) and the electron donor (b) are selected and used so that MFR(a)co≧1, 5 is satisfied.

In the present invention, as the electron donor used in preparing the electron 1j% Lj body catalyst component [C], the above-mentioned electron donor used in preparing the solid titanium 6 catalyst component [A] is used. However, in particular, the electron donor (a)
, (b) are preferably selected from the following organosilicon compounds.

As such an organosilicon compound, an organosilicon compound represented by the following general formula [11] can be used.

RSi (OR') 4-n-[N [wherein R and R' are hydrocarbon groups and 0xn<4] As an organosilicon compound represented by the above general formula [1] Specifically, trimethylmethoxysilane, trimethylethoxysilane, dimethyldimethoxysilane, dimethyljethoxysilane, diisopropyldimethoxysilane, t-butylmethyldimethoxysilane, t-butylmethyljetoxysilane, t-amylmethyljetoxy Silane, diphenyldimethoxysilane, phenylmethyldimethoxysilane, diphenyljethoxysilane,
Bis-o-tolyldimethoxysilane, bis m-)lyldime7 toxysilane, bis-p-tolyldimethoxysilane bis I
)-1-lyldiethoxysilane, bisethyl phenyldimethoxysilane, dicyclohexyldimethoxysilane,
Cyclohexylmethyldimethoxysilane, cyclohexylmethyljethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilanemethoxysilane, n-propyltriethoxysilane, decyltrimethoxysilane, decyltriethoxysilane,
Phenyltrimethoxysilane, γ-chloropropyltrimethoxysilane silane triethoxysilane, t-butyltriethoxysilane, n-butyltriethoxysilane, Iso-butyltriethoxysilane, phenyltriethoxysilane γ-aminopropyl I. silane, chloro)-ethoxysilane, ethyl I-liisopropoxysilane, vinyltributoxysilane, cyclohexyltrimethoxysilane, cyclohexyltriethoxysilane, 2-norbornanetriethoxysilane, 2-norbornanemethyldimethoxy Silane, ethyl silicate, butyl silicate, trimethylphenoxysilane, methyltriaryloxysilane, vinyltris(β)
-methoxyethoxysilane), vinyltriacetoxysilane siloxane, etc. are used.

Two or more types of these electron donors can be used.

Among the organosilicon compounds mentioned above, examples of organosilicon compounds (published by I) include compounds with the following general formula [1
1] is preferably used.

R'Si(OR2)2. ... [II] In the formula,
R1 is a hydrocarbon group in which the carbon adjacent to Si is secondary or tertiary, specifically, isopropyl group, Se
Alkyl groups such as Q-butyl group, t-butyl group, t-amyl group, cycloalkyl group such as cyclopentyl group, cyclohexyl group, cycloalkenyl group such as cyclopentenyl group, aryl group such as phenyl group, tolyl group Examples include groups.

Among these, alkyl groups and cycloalkyl groups are preferred.

Further, in the above formula [111, R2 represents a hydrocarbon group. The hydrocarbon group preferably has 1 to 5 carbon atoms, particularly preferably 1 to 2 carbon atoms.

Specifically, such organosilicon compounds (E1) include diisopropyldimethoxysilane, diisopropyljethoxysilane, disee-butyldimethoxysilane, diphenyldimethoxysilane, diphenyldimethoxysilane, dicyclopentyldimethoxysilane, and dicyclohexyl. Dimethoxysilane, diphenyldimethoxysilane, bis0-tolyldimethoxysilane, lanthylphenyldimethoxysilane, and the like are preferably used.

Further, among the organosilicon compounds as described above, as the organosilicon compound (RO), for example, a compound represented by the general formula [■] such as 0 below is preferably used.

In the formula, when n is 2, each R1 is a hydrocarbon group, and at least one of the groups is a hydrocarbon group in which the carbon adjacent to Si is primary, specifically, an ethyl group, n-propyl groups, alkyl groups such as n-butyl groups, aralkyl groups such as cumyl and benzyl groups, and alkenyl groups such as vinyl groups.

In the formula, R2 represents a hydrocarbon group, preferably a hydrocarbon group having 1 to 5 carbon atoms, particularly preferably 1 to 2 carbon atoms.

Specific examples of such organosilicon compounds (low ■) in which n is 2 in the above formula include diethyldimethoxysilane, dipropyldimethoxysilane, dibutyldimethoxysilane, dibenzyldimethoxysilane, and divinyldimethoxysilane. Preferably used.

Furthermore, in the above formula [ml, 0≦n (2 or 2×n<4, R1 is a hydrocarbon group, and specific examples 1 include an alkyl group, a cycloalkyl group, an alkenyl group,
These include aryl groups and aralkyl groups.

R2 is a hydrocarbon group, preferably having 1 to 5 carbon atoms, particularly preferably 1 to 2 carbon atoms.

Such the above formula [in ml, O≦n<2 or 2<n<
Specifically, the organosilicon compound (Row 1) which is 4 includes trimethylmethoxysilane, trimethylethoxysilane, methylphenyldimethoxysilane, methyltrimethoxysilane, t-butylmethyldimethoxysilane, t-butylmethyldimethoxysilane, and t-butylmethyldimethoxysilane.
-butylmethyljethoxysilane, t-amylmethyldimethoxysilane, phenylmethyldimethoxysilane, cyclohexylmethyldimethoxysilane, cyclohexylmethyljethoxysilane, ethyltrimethoxysilane,
Ethyltriethoxysilane, Vinyltriethoxysilane, Methyltrimethoxysilane, Methyltriethoxysilane, Propyltrimethoxysilane, Decyltrimethoxysilane, Decyltriethoxysilane, Phenyltrimethoxysilane 2 Lopyltriethoxysilane, Butyltriethoxysilane , phenyltriethoxysilane, vinyltrimethoxysilanecyclohexyltrimethoxysilane, 2-norbornanetrimethoxysilane, 2-norbornanetrimethoxysilane, etc. are used.

Among these, methyltrimethoxysilane, ethyltrimethoxysilane, ethyl I-liethoxysilane, vinyltriethoxysilane, propyltrimethoxysilane, decyltrimethoxysilane siltriethoxysilane, propyltriethoxysilane, butyltriethoxysilane,
Phenyltriethoxysilane, vinyl I.rimethoxysilane, vinyltributoxysilane, cyclohexyltrimethoxysilane and the like are preferably used.

As for the organosilicon compounds mentioned above, compounds that can induce these organosilicon compounds under olefin polymerization conditions or prepolymerization conditions are added during olefin polymerization or prepolymerization, and organosilicon compounds are added at the same time as olefin polymerization or prepolymerization. 3. It may also be used to generate a product.

In the polymerization method of the present invention, it is preferable to polymerize the olefin in the presence of the catalyst as described above, or to perform prepolymerization as described below before such polymerization (main polymerization).

By performing such prepolymerization, a powder polymer having a large bulk density can be obtained, and the stereoregularity of the obtained olefin polymer tends to be improved. In addition, if prepolymerization is performed, the properties of the slurry will be excellent in the case of slurry polymerization.

Therefore, according to the polymerization method of the present invention, the obtained polymer powder or polymer slurry can be easily handled.

In prepolymerization, the solid titanium catalyst component [
A] is used in combination with at least a portion of the organoaluminum compound catalyst component [B].

At this time, part or all of the electron donor catalyst component [C] may be allowed to coexist.

In the prepolymerization, a catalyst can be used at a much higher concentration than the catalyst concentration in the system in the main polymerization.

4 The concentration of solid titanium catalyst component [A] in prepolymerization is:
Usually about 0.01 to 200 mmol, preferably about 0 in terms of titanium atoms, per 1 p of the inert hydrocarbon medium described below.
．． The preferred range is 0.05 to 100 mmol.

The amount of the organoaluminum catalyst component [B] is 0.1 to 500 g, preferably 0.1 to 500 g per 1 g of the solid titanium catalyst component [A].
The amount may be such that 3 to 300 g of polymer is produced, and is usually about 0.1 to 100 mol, preferably about 0.5 to 5 mol, per 1 mol of titanium atoms in the solid titanium catalyst component [A].
Preferably, the amount is 0 mole.

Prepolymerization is preferably carried out under mild conditions by adding the olefin and the catalyst components described above to an inert hydrocarbon medium.

Examples of the inert hydrocarbon medium used in this case include aliphatic hydrocarbons such as propane, butane, pentane, hexane, heptane, octane, decane, dodecane, and kerosene; cyclopentane, cyclohexane, and methyl Schiff 50 pentane. Examples include alicyclic hydrocarbons such as; aromatic hydrocarbons such as benzene, toluene, and xylene; halogenated hydrocarbons such as ethylene chloride and chlorobenzene; and mixtures thereof. Among these inert hydrocarbon media, it is particularly preferable to use aliphatic hydrocarbons.

The olefin used in the preliminary polymerization may be the same as or different from the olefin used in the main polymerization described later.

When such an olefin is used in prepolymerization, a highly crystalline polymer can be obtained from an α-olefin having 2 to 10 carbon atoms, preferably 3 to 10 carbon atoms.

In addition, in the present invention, liquid α-
Olefins can be used.

The reaction temperature for prepolymerization may be any temperature at which the prepolymer to be produced does not substantially dissolve in the inert hydrocarbon medium, and is usually about -20 to +100°C, 6 preferably about -20 to +80°C. , more preferably O~
A range of +40°C is desirable.

In addition, in the prepolymerization, a molecular weight regulator such as hydrogen can also be used. Such a molecular weight modifier is 1
The intrinsic viscosity [η] of the polymer obtained by prepolymerization with constant δ-1 in decalin at 35°C is about 0.2 dl! It is desirable to use an amount of at least 0.5 to 10 di)/g, preferably about 0.5 to 10 di)/g.

The prepolymerization was carried out using the titanium catalyst component [A11g
about 0.1-1000g, preferably about O13-50
It is desirable to perform this so that 0 g of polymer is produced.

If the amount of preliminary polymerization is too large, the production efficiency of the olefin polymer in the main polymerization may decrease.

Prepolymerization can be carried out batchwise or continuously.

After prepolymerizing as described above or without prepolymerizing, the solid titanium catalyst component [
A], organoaluminum catalyst component 7 [B] and at least two or more electron donor catalyst components [C].

Olefins that can be used in this polymerization include ethylene, propylene, ■-butene, 4-methyl-
Examples include 1-pentene and -octene. In the polymerization method of the present invention, these olefins are used alone,
Or they can be used in combination. Among these olefins, homopolymerization is carried out using propylene or 1-butene, or propylene or l-butene is used for homopolymerization;
- It is preferable to carry out the copolymerization using a mixed olefin containing butene as a main component. When such a mixed olefin is used, the content of the main component, propylene or -butene, is usually 50 mol% or more, preferably 70 mol% or more.

In the polymerization method of the present invention, a polymer having a high stereoregularity index can be produced with high catalytic efficiency by particularly polymerizing an α-olefin having 3 or more carbon atoms.

8 In addition, when performing homopolymerization or copolymerization of these olefins, compounds having polyunsaturated bonds such as conjugated dienes and non-conjugated dienes can also be used as polymerization raw materials.

In the polymerization method of the present invention, the main polymerization of olefin is usually carried out in a gas phase or a liquid phase.

When the main polymerization takes the reaction form of slurry polymerization, the above-mentioned inert hydrocarbon can be used as the reaction solvent, or an olefin that is liquid at the reaction temperature can also be used.

In the polymerization method of the present invention, the titanium catalyst component [A
] is usually about 0.005 to 0.5 mmol, preferably about 0.01 to 0.5 mmol, in terms of TI atoms per 1 g of polymerization volume.
It is used in an amount of 0.5 mmol. In addition, the organoaluminum compound catalyst component [B] usually contains about 1 to 2 metal atoms in the organoaluminum compound catalyst component [B] per 1 mole of titanium atoms in the titanium catalyst component [A] in the polymerization system.
000 mol, preferably about 5 to 500 mol. Furthermore, the electron donor catalyst component [C] is calculated in total in terms of 31 atoms in the electron donor catalyst component [C] per 1 mole of metal atoms in the organoaluminum compound catalyst component [B], and is usually about 0.001~10
The amount used is such that the amount is mol, preferably about 0.01 to 2 mol, particularly preferably about 0.05 to 1 mol.

In the polymerization method of the present invention, titanium catalyst component [A],
The organoaluminum compound catalyst component [B] and at least two or more electron donor catalyst components [C] may be brought into contact during main polymerization, or may be brought into contact before main polymerization, for example, during prepolymerization.

In this contacting before main polymerization, only any three components may be freely selected and brought into contact, or a part of each component may be brought into contact with three parties or three parties.

Further, an electron donor (
For a) and (b), both components may be used during prepolymerization, or one component may be used during prepolymerization and the other during main polymerization, or even both components may be used for the first time during main polymerization. May be used.

In the polymerization method of the present invention, each catalyst component may be contacted in an inert gas atmosphere or in an olefin atmosphere before polymerization.

In addition, the organoaluminum compound catalyst component [B
] and a part of the electronic gradient catalyst component [C], the catalyst used in the prepolymerization is used together with the remaining catalyst. In this case, the catalyst used in the prepolymerization may contain a prepolymerization product.

If hydrogen is used during the main polymerization, the molecular weight of the resulting polymer can be adjusted and a polymer with a high melt flow rate can be obtained. Even in this case, in the polymerization method of the present invention, the stereoregularity index of the produced polymer does not decrease, nor does the catalytic activity decrease.

In the present invention, the polymerization temperature of the olefin is usually about 2
0-200°C, preferably about 50-180°C, the pressure is
Normal pressure ~100 kg/c+#.

Preferably it is set to about 2 to 50 kg/c-. In the polymerization method of the present invention, the polymerization can be carried out in a batch method, a half-speed continuous method, or a continuous method. Furthermore, the polymerization can be carried out in two or more stages by changing the reaction conditions.

The olefin polymer thus obtained may be a homopolymer, a random copolymer, a block copolymer, or the like.

In the present invention, since the yield of a polymer having stereoregularity per median amount of the solid catalyst component is high, the catalyst residue of the polymer, especially the halogen content, can be relatively reduced. Therefore, it is possible to omit the operation of removing the catalyst in the regular polymer, and when molding a molded article using the produced olefin polymer, rusting of the mold can be effectively prevented.11. °I can do something.

The olefin polymer obtained using the catalyst according to the present invention has a wide molecular weight distribution and therefore has excellent processability during melt molding.

Effects of the Invention The olefin polymerization method of the present invention provides a specific olefin polymerization method formed from a solid titanium catalyst component [A], an organoaluminum compound catalyst component [B], and at least two or more specific electron 2 donor catalyst components [C]. Since olefin polymerization is carried out using a polymerization catalyst, an olefin polymer having a particularly wide molecular weight distribution can be produced in high yield.

Moreover, the olefin polymerization method of the present invention not only broadens the molecular weight distribution, but also yields an unexpected result in that high molecular weight components, which could not be obtained in conventional single-stage polymerization, are produced (first step). (shown in the figure), this high molecular weight component can also improve the strength of the olefin polymer.

The olefin polymer obtained by the polymerization method of the present invention has high stereoregularity and high bulk density.

Furthermore, the catalyst of the present invention can efficiently produce an olefin polymer having the above-mentioned excellent properties, and there is little decrease in catalyst activity with the passage of polymerization time.

Hereinafter, the present invention will be explained in more detail with reference to Examples.
The present invention is not limited to these examples.

3 Example 1 [Preparation of solid titanium catalyst component [A]] Anhydrous magnesium chloride 7, 1.4K (75 mmol), 37.5 ml of decane and 35. 1 ml (225 mmol) at 130°C
A heating reaction was carried out for 2 hours to give a homogeneous solution of 1/1. Thereafter, 67 g (11,8
mmol) was added thereto, and the mixture was further stirred and mixed at 130° C. for 1 hour to dissolve phthalic anhydride into the above homogeneous solution.

After cooling the homogeneous solution thus obtained to room temperature, 200 ml of titanium tetrachloride (
The entire amount was added dropwise to the solution (1.8 mol) over 1 hour. After the dropwise addition, the temperature of the obtained solution was raised to 110°C over 4 hours, and when it reached 110°C, diisobutyl phthalate was added.
5. 03 ml (18.8 mmol) were added.

Stirred for an additional 2 hours at the above temperature. After 2 hours of reaction, the solid part was collected by filtration while hot, and this solid part was
After resuspending in ml of T ] CR4, the reaction was heated again at 1.10° C. for 2 hours.

After the reaction, the solid part was collected again by hot filtration and heated to 110°
Washed with C decane and hexane.

This cleaning was continued until no titanium compound was detected in the cleaning solution.

Solid titanium catalyst component [A] synthesized as above
was obtained as a hexane slurry.

A portion of this catalyst was collected and dried. Analysis of this dried material revealed that the composition of the solid titanium catalyst component [A] obtained as described above was 2.5% titanium, 96% chlorine, and 5% chlorine.
8% by weight, 18% by weight of magnesium, and 1.13.8% by weight of diisobutyl phthalate.

[Prepolymerization] Purified hexane 20 On+1 was placed in a 400 ml glass reactor purged with nitrogen, and 6 mm of triethylaluminum (2 mmol in terms of titanium atoms) was added, and then 5.9 Nj
)/hour for 1 hour, and 2.8 g of 5-propylene was polymerized per 1 g of TI catalyst component [A].

After the preliminary polymerization was completed, the liquid portion was removed by filtration, and the separated solid portion was again dispersed in decane.

[Main polymerization] Purified hexane 750 in an autoclave with an internal volume of 2 g
ml of trimethylaluminum, 0.038 mmol of dicyclopentyldimethoxysilane, 0.038 mmol of propyltriethoxysilane and the catalyst component [A] in a propylene atmosphere at room temperature.
0.015 mmol in terms of titanium atoms (equivalent to 4.48 mg in terms of the catalyst component [A]) was added to the prepolymerized product. After adding 200 N ml of hydrogen, the temperature was raised to 70°C and propylene polymerization was carried out for 2 hours. The pressure during polymerization was kept at 7 kg/cIilG.

After the polymerization was completed, the slurry containing the produced polymer was filtered and separated into a white granular polymer and a liquid phase. Extraction residue rate with boiling n-hbutane after drying, MFR, apparent bulk specific gravity, polymerization activity, II of total polymer, molecular weight distribution by GPC (Mw
/Mn), and when catalyst component 6 [C] was used alone. FR(a), M
FR (b) and log [M FR (b)
/MFR(a)] are shown in Table 1.

Example 2 Propylene was polymerized in the same manner as in Example 1, except that vinyltriethoxysilane was used instead of propyltriethoxylane.

The results are shown in Table 1.

Furthermore, the results of GPC analysis of the obtained polymer are shown in FIG.

Example 3 Propylene was polymerized in the same manner as in Example 1, except that β-phenethylmethyljethoxysilane was used instead of propyltriethoxysilane.

The results are shown in Table 1.

Examples 4 to 6 Propylene was polymerized in the same manner as in Example except that di-t-butyldimethoxysilane was used instead of dicyclopentyldimethoxysilane in the polymerizations of Examples 1 to 3.

The results are shown in Table 1.

Comparative Examples 1 to 2 In the polymerization of Example 1, two types of silane compounds were used,
0.075 mmol of cyclohexylmethyldime I xysilane or 0.075 mmol of vinyl I xysilane
Polypropylene was polymerized in the same manner as in Example 1, except that mmol was used.

The results are shown in Table 1.

Furthermore, the results of GPC analysis of the obtained polymer are shown in FIG.

Japanese Patent Application Publication No. 3-7703 (16)

[Brief explanation of drawings]

FIG. 1 is a diagram showing a GPC curve of polypropylene obtained in the present invention, and FIG. 2 is a flow chart 1 showing an example of a catalyst preparation method in the olefin polymerization method according to the present invention.

Claims (1)

[Scope of Claims] 1) [A] a solid titanium catalyst component containing magnesium, titanium, halogen, and an electron donor as essential components, [B] an organoaluminum compound catalyst component, and [C] an electron donor (a) and at least two or more types of electron donor catalyst components containing an electron donor (b) (provided that the electron donor (a) is obtained by using the above solid titanium catalyst component [A] and organoaluminum compound catalyst component [B]). The MFR (a) of the homopolypropylene obtained by using the electron donor (b) and the MFR (b) of the homopolypropylene obtained by using the electron donor (b) under the same polymerization conditions as the electron donor (a) are expressed as log [MFR (b) /MFR(a)]≧1.5). 2) [A] A solid titanium catalyst component containing magnesium, titanium, halogen, and an electron donor as essential components, [B] an organoaluminum compound catalyst component, and [C] an electron donor (a) and an electron donor (ro). ) at least two or more types of electron donor catalyst components, including MFR of homopolypropylene obtained by using the electron donor (a) together with the solid titanium catalyst component [A] and the organoaluminum compound catalyst component [B]. (a) and the MFR (b) of homopolypropylene obtained by using the above electron donor (b) under the same polymerization conditions as the electron donor (a)
A catalyst for olefin polymerization, characterized in that it is formed from log[MFR(b)/MFR(a)]≧1.5).