WO2012096404A1

WO2012096404A1 - Solid catalyst component for olefin polymerization

Info

Publication number: WO2012096404A1
Application number: PCT/JP2012/050882
Authority: WO
Inventors: Mitsuhiro Okada; Wataru Hirahata
Original assignee: Sumitomo Chemical Company, Limited
Priority date: 2011-01-12
Filing date: 2012-01-11
Publication date: 2012-07-19
Also published as: TW201241021A; JP2012158744A

Abstract

There are provided (1) a solid catalyst component for olefin polymerization containing a titanium atom, a magnesium atom, a halogen atom and an internal electron donor represented by defined formula (I), such as diethyl 2,5-dioxahexanedioate, (2) a process for producing the solid catalyst component, (3) a process for producing a solid catalyst, and (4) a process or producing an olefin polymer.

Description

DESCRIPTION

SOLID CATALYST COMPONENT -FOR OLEFIN POLYMERIZATION Technical Field

The present invention relates to (1) a solid catalyst component for olefin polymerization, (2) a process for producing a solid catalyst component for olefin polymerization, (3) a process for producing a solid catalyst for olefin polymerization, and (4) a process for producing an olefin polymer.

Background Art

As an olefin polymerization catalyst, JP64-81803A discloses an olefin polymerization catalyst obtained by using an internal electron donor of a structurally-complex oligomer having both a carbonate group and an ether group; JP6-100639A discloses an olefin polymerization catalyst obtained by using an internal electron donor of diethyl carbonate; and JP6-9722A (corresponding to US patent 4,952,649) discloses- an olefin polymerization catalyst obtained by using, as an internal electron donor, a linear carbonate such as dimethyl carbonate and diethyl carbonate, or a cyclic carbonate such as propylene carbonate . Summary of Invention

However, all of the above olefin polymerization catalysts are not yet satisfactory, because those olefin polymerization catalysts produce an olefin polymer containing a component soluble in an organic solvent at low temperature, such as a low-molecular weight component and an amorphous component. An object of the present invention is to provide (1) a solid catalyst component for olefin polymerization which has a high polymerization activity, and gives an olefin polymer containing only a small amount of a component soluble in an organic solvent at low temperature, (2) a process for producing such a solid catalyst component for olefin polymerization, (3) a process for producing a solid catalyst for olefin polymerization, and (4) a process for producing an olefin polymer.

The present invention is a solid catalyst component for olefin polymerization comprising a titanium atom, a magnesium atom, a halogen atom and an internal electron donor represented by formula (I) :

(I) wherein each R is independently a hydrocarbyl group having 1 to 20 carbon atoms, or the two R groups are linked together to form a ring; each X is. independently an oxygen atom or a sulfur atom; Z is an optionally substituted hydrocarbylene group having 1 to 20 carbon atoms; and n is an integer of 1 to 100.

Also, the present invention is a process for producing a solid catalyst component for olefin polymerization comprising a titanium atom, a magnesium atom, a halogen atom and an internal electron donor represented by above formula (I), the process comprising a step of bringing a titanium compound, a magnesium compound and the internal electron donor into contact with each other.

Further, the present invention is a process for producing a solid catalyst for olefin polymerization, the process comprising a step of bringing the above solid catalyst component or a solid catalyst component produced by the above process for producing a solid catalyst component for olefin polymerization, an organoaluminum compound and, optionally, an external electron donor into contact with each other.

Still further, the present invention is a process for producing an olefin polymer, the process comprising a step of polymerizing an olefin in the presence of a solid catalyst produced by the above process for producing a solid catalyst for olefin polymerization.

The above "solid catalyst component for olefin polymerization" and "solid catalyst. for olefin polymerization" are hereinafter referred to simply as "solid catalyst component" and "solid catalyst", respectively.

Description of Embodiments

Each X in formula (I) is independently an oxygen atom or a sulfur atom.

X in formula (I) is preferably an oxygen atom.

Above n in formula (I) is an integer of 1 to 100, preferably an integer of 1 to 10, more preferably an integer of 1 to 3, and still more preferably 1.

Each R in formula (I) is independently an optionally substituted hydrocarbyl group having 1 to 20 carbon atoms, more preferably an optionally substituted hydrocarbyl group having 1 to 10 carbon atoms.

Examples of the above hydrocarbyl group are an alkyl group, ^'an aralky group, an aryl group and an alkenyl group. Those groups may have a substituent such as a halogen atom, a hydrocarbyloxy group, a nitro group, a sulfonyl group and a silyl group.

Examples of the above alkyl group are a linear alkyl group such as a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group and an n-octyl group; a branched alkyl group such as an isopropyl group, an isobutyl group, a tert-butyl group, an isopentyl group, a neopentyl group and a 2-ethylhexyl group; and a cycloalkyl group such as a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group and a. cyclooctyl group. Among them, preferred is a linear, branched or cyclic alkyl group having 1 to 10 carbon atoms; and more preferred is a linear or branched alkyl group having 1 to 10 carbon atoms.

Examples of the above aralky group are a benzyl group and a phenethyl group. Among them, preferred is an aralkyl group having 7 to 10 carbon atoms.

Examples of the above aryl group are a pheny group, a tolyl group and a xylyl group. Among them, preferred is an aryl group having 6 to 10 carbon atoms.

Examples of the above alkenyl group are a linear alkenyl group such as a vinyl group, an allyl group, a 3- butenyl group and . a 5-hexenyl group; a branched alkenyl group such as an isobutenyl group and■ a 5-methyl-3-pentenyl group; and a cycloalkenyl group such as a 2-cyclohexenyl group and a 3-cyclohexenyl group. Among them, preferred is an alkenyl group having 2 to 10 carbon atoms.

The two R groups may be linked together to form a ring. The ring comprises an optionally substituted hydrocarbylene group having 1 to 20 "carbon atoms, more preferably an optionally substituted hydrocarbylene group having 1 to 10 carbon atoms .

Examples of the above hydrocarbylene group composing the ring are an alkylene group, an arylene group and a group containing a combination of an alkylene group with an arylene group. Those groups -may have a substituent such as a halogen atom, a hydrocarbyloxy group, a nitro group, a sulfonyl group and a silyl group.

Examples of the above alkylene group are a linear alkylene group such as an ethylene group, a propylene group, an n-butylene group, an n-penthylene group and an n- hexylene group; a branched alkylene group such as an isopropylene group, an isobutylene group and an isopentylene group; and a cycloalkylene group such as a cyclopropylehe . group, a cyclobutylene group, a cyclopentylene group, a cyclohexylene group, a cycloheptylene group and a cyclooctylene group. Among them, preferred is a linear, branched or cyclic alkylene group having 1 to 10 carbon atoms; and more preferred is a linear or branched alkylene group having 1 to 10 carbon atoms.

Examples of the above arylene group are a phenyene group, a tolylene group and a xylylene group. Among them, preferred is an arylene group having 6 to 10 carbon atoms.

Z in above formula (I) is an optionally substituted hydrocarbylene group having 1 to 20 carbon atoms, preferably an optionally substituted hydrocarbylene group having 1 to 10 carbon atoms.

Examples of the above hydrocarbylene group of Z in above formula (I) are an alkylene group, an arylene group and a group containing a combination of an alkylene group with an arylene group. Those groups may have a substituent such as a halogen atom, a nitro group, a sulfonyl group and a silyl group.

Examples of the above alkylene group are a linear alkylene group such as an ethylene group, a propylene group, an n-butylene group, an n-penthylene group and an n- hexylene group; a branched alkylene group such as an isopropylene group, an isobutylene group and an isopentylene group; and a cycloalkylene group such as a cyclopropylene group, a cyclobutylene group, a cyclopentylene group, a cyclohexylene group, a cycloheptylene group and a cyclooctylerte group. Among them, preferred is a linear, branched or cyclic alkylene group having 1 to 10 carbon atoms; and more preferred is a linear or branched alkylene group having 1 to 10 carbon atoms.

Examples of the above arylene group are a pheny group, a tolylene group and a xylylene group. Among them, preferred is an arylene group having 6 to 10 carbon atoms.

Among them, Z is preferably an optionally substituted alkylene group having 1 to 10 carbon atoms or an arylene groups. Z is more preferably a linear or branched alkylene group having 1 to 10 carbon atoms, and still more preferably a linear alkylene group having 1 to 10 carbon atoms . still more preferably an optionally substituted alkylene group having 1 to 6 carbon atoms.

An internal electron donor represented by formula (I) is preferably a compound represented by the following formula:

wherein each Y is independetly a hydrogen atom, a halogen atom or a hydrocarbyl group having 1 to 10 carbon atoms, or the two Y groups are linked together to form a ring; and m is an integer of 1 to 10.

An internal electron donor represented by formula (I) may be a compound known in the art. Examples thereof are compounds represented by the following respective formulas, wherein carbon atoms and hydrogen atoms are omitted; for example, the following .first formula means CH₃-0-CO-0-CH₂- CH₂-0-CO-0-CH₃ (dimethyl 2 , 5-dioxahexanedioate ) :

The solid catalyst component of the present invention is not particularly limited in its production method. One example of the production method is a method comprising a step of bringing a titanium compound, a magnesium compound and the internal electron donor represented by formula (I) into contact with each other. This method corresponds to the process for producing a solid catalyst component of the present invention, which is referred to hereinafter as "catalyst component production method-1". The above step in catalyst component production method-1 may comprise sub- steps of (1) bringing a titanium compound into contact with a magnesium compound, thereby producing a solid component comprising a titanium atom and a magnesium atom, and then (2) bringing the solid component into_, contact with an internal electron donor represented by formula (I) . The method comprising _. sub-steps (1) and (2) is referred to hereinafter as "catalyst component production method-2".

The above titanium compound is not particularly limited, as long as it contains a titanium atom. Examples of the titanium compound are a titanium tetrahalide such, as titanium tetrachloride, titanium tetrabromide and titanium tetraiodide ; a tetraalkoxytitanuim such . as tetramethoxytitanium, tetraethoxytitanium, tetra-n- propoxytitanium, tetraisopropoxytitanium, tetra-n- butoxytitanium, tetraisobutoxytitanium and tetracyclohexyloxytitanium; a tetraaryloxytitanium such as tetraphenoxytitanium; an alkoxytitanium trichloride such as methoxytitanium trichloride, ethoxytitanium trichloride, n- propoxytitanium trichloride and n-butoxytitanium trichloride; a dialkoxytitanium dichloride such as dimethoxytitanium dichloride, diethoxytitanium dichloride, diisopropoxytitanium dichloride and di-n-propoxytitanium dichloride; a trialkoxytitanium monochloride such as trimethoxytitanium chloride, triethoxytitanium chloride, triisopropoxytitanium chloride, tri-n-propoxytitanium chloride and tri-n-butoxytitanium chloride; and a combination of two or more thereof. In catalyst component production method-1, among them, preferred is a titanium tetrahalide or an alkoxytitanium trichloride, more preferred is a titanium .tetrahalide, and further preferred is titanium tetrachloride.

The above magnesium compound is not particularly limited, as long as it contains a magnesium atom. In catalyst component production method-1, examples of the magnesium compound are those represented by following formula (i) or (ii) :

wherein each R¹ is independently an optionally substituted hydrocarbyl group having 1 to 20 carbon atoms; each X¹ is independently a halogen atom; and a is an integer satisfying 0 ≤ a ≤ 2.

Examples of R¹ are an alkyl group, an aralkyl group, an aryl group and an alkenyl group. Those groups may have a substituent such as a halogen atom, a hydrocarbyloxy group, a nitro group, a sulfonyl group, and a silyl group.

Examples of the above alkyl group are a linear alkyl group such as a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group and an n-octyl group; a branched alkyl group such as an isopropyl group, an isobutyl group, a tert-butyl group, an isopenty group, a neopentyl group and a 2-ethylhexyl group; and a cycloalkyl group such as a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group and a cyclooctyl grouop. Among them, preferred is a linear or branched alkyl group having 1 to 20 carbon atoms.

Examples of the above aralkyl group are a benzyl group and a phenethyl group. Among them, preferred is an aralkyl group having 7 to 20 carbon atoms.

Examples of the above aryl group are a pheny group, a naphthyl group and a tolyl group. Among them, preferred is an aryl group having 6 to 20 carbon atoms.

Examples of the above alkenyl group are a linear alkenyl group such as a vinyl group, an allyl group, 3- butenyl group and a 5-hexenyl group; a branched alkenyl group such as an isobutenyl group and a 4-methyl-3-pentenyl group; and a cycloalkenyl group such as 2-cyclohexenyl group and a 3-cyclohexenyl group. Among them, preferred is a linear or branched alkenyl group having 2 to 20 carbon atoms .

Examples of the halogen atom of above X¹ are a chlorine atom, a bromine atom an iodine atom and a fluorine atom. Among them, preferred is a chlorine atom. - Examples of the magnesium compound represented by above formula (i) or (ii) are a dialkylmagnesium such as dimethylmagnesium, diethylmagnesium, di-n-propylmagnesium, diisopropylmagnesium, di-n-butylmagnesium, diisobutylmagnesium, di-tert-butylmagnesium, di-n- hexylmagnesium, di-n-octylmagnesium, ethyl-n-butylmagnesium and n-butyl-n-octylmagnesium; a dialkoxymagnesium such as dimethoxymagnesium, diethoxymagnesium, di-n- propoxymagnesium, diisopropoxymagnesium, di-n- butoxymagnesium, diisobutoxymagnesium, di-tert- butoxymagnesium, di-n-hexyloxymagnesium, di-n- octyloxymagnesium, ethoxy-n-butoxymagnesium and n-butoxy-n- octyloxymagnesium; an alkylmagnesium halide such as methylmagnesium chloride, ethylmagnesium chloride, n- propylmagnesium chloride, isopropylmagnesium chloride, n- butylmagnesium chloride, isobutylmagnesium chloride, tert- butylmagnesium chloride, methylmagnesium bromide, ethylmagnesium bromide, n-propylmagnesium bromide, isopropylmagnesium bromide, n-butylmagnesium bromide, isobutylmagnesium bromide, tert-butylmagnesium bromide, methylmagnesium iodide, ethylmagnesium iodide, n- propylmagnesium iodide, isopropylmagnesium iodide, n- butylmagnesium iodide, isobutylmagnesium iodide, and tert- butylmagnesium iodide; an aralkymagnesium halide such as benzylmagnesium chloride, benzylmagnesium bromide and benzylmagnesium iodide; an alkoxymagnesium halide such as methoxymagnesium chloride, ethoxymagnesium chloride, isopropoxymagnesium chloride, n-butoxymagnesium chloride, n-hexyloxymagnesium chloride, methoxymagnesium bromide, ethoxymagnesium bromide, isopropoxymagnesium bromide, n- butoxymagnesium bromide, n-hexyloxymagnesium bromide, methoxymagnesium iodide, ethoxymagnesium iodide, isopropoxymagnesium iodide, n-butoxymagnesium iodide and n- hexyloxymagnesium iodide; and a magnesium halide such as magnesium fluoride, magnesium chloride, magnesium bromide, and magnesium iodide. Among them, preferred is a dialkoxymagnesium, an alkoxymagnesium halide or a magnesium halide.

The above dialkoxymagnesium is preferably a dialkoxymagnesium having 1 to 20 carbon atoms, further preferably a dialkoxymagnesium having 1 to 10 carbon atoms, and .particularly preferably dimethoxymagnesium, diethoxymagnesium, di-n-propoxymagnesium, diisopropoxymagnesium, di-n-butoxymagnesium, diisobutoxymagnesium or di-tert-butoxymagnesium.

The above dialkoxymagnesium can be produced, for example, by bringing magnesium metal into^' contact with alcohol such as methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol and n-octanol, in the presence of a catalyst. Examples of the catalyst are halogen such as iodine, chlorine and bromine; and a magnesium halide such as magnesium iodide and magnesium chloride. Among them, preferred is iodine.

The above alkoxymagnesium halide is preferably an alkoxymagnesium chloride having 1 to 20 carbon atoms, further preferably an alkoxymagnesium chloride having 1_. to 10 carbon atoms, and particularly preferably methoxymagnesium chloride, ethoxymagnesium chloride, n- propoxymagnesium chloride, isopropoxymagnesium chloride, n- butoxymagnesium chloride, isobutoxymagnesium chloride or tert-butoxymagnesium chloride.

The above magnesium halide is preferably magnesium chloride. Magnesium chloride is used in its solid state, or solution state in which magnesium chloride is dissolved in_. a solvent such as an alcohol (for example, methanol, ethanol and 2-ethylhexylalcohol) , or a hydrocarbyl solvent (for example, toluene and hexane) . Magnesium chloride may be an adduct such as an alcohol adduct, an ether, adduct and an ester adduct.

In catalyst component production method-1, the above magnesium compound may be supported on a carrier. The carrier is not particularly limited in its kind. Examples thereof are a porous inorganic oxide such as Si0₂, A1₂0₃, MgO, Ti0₂ and Zr0₂; and a porous organic polymer such as polystyrene, a styrene-divinylbenzene copolymer, a copolymer of styrene with a monomer, CH₂=C (CH₃) COO-CH₂CH₂- OCOC (CH₃) =CH₂, obtained by a reaction between ethylene glycol and methacrylic acid, polymethyl acrylate, polyethyl acrylate, a methyl acrylate-divinylbenzene copolymer, polymethyl methacrylate, a methyl methacrylate- divinylbenzene copolymer, polyacrylonitrile, an acrylonitrile-divinylbenzene copolymer, polyvinyl chloride., polyethylene and polypropylene. Among them, preferred is a porous inorganic oxide, and particularly preferred is Si0₂. In order to support a magnesium compound effectively on the carrier, the carrier has a pore volume of preferably 0.3 cmVg or more, and more preferably 0.4 cm³/g or more, in a pore radius range of 20 to 200 nm, a proportion of which pore volume is preferably 35% or more, and more preferably 40% or more,^' provided that a proportion of a pore volume in a pore radius range of 3.5 to 7, 500 nm is 100%.

Catalyst component production method-1 uses the titanium compound in an amount of usually 0.1 to 1,000 mmol, preferably 0.3 to 500 mmol, and particularly preferably 0.5 to 300 mmol, per mole of a magnesium atom contained in the magnesium compound to be used. The titanium compound is used at one time, or in two or more batches.

Catalyst component production ^' method-1 uses the internal electron donor represented by formula (I) in an amount of usually 0.1 to 1, 000 mmol, preferably .0.3 to 500 mmol, and particularly preferably 0.5 to 300 mmol, per mole of a magnesium atom contained in the magnesium compound to be used. The internal electron donor is used at one time, or in two or more batches.

Catalyst component production method-1 is not particularly limited in its method for bringing a titanium compound, a magnesium compound and an internal electron donor represented by formula (I) into concact with -each other. Examples of the method may be those known in the art, such as (1-1) a slurry method, and (1-2) a mechanically pulverizing method using a ball mill..

Above slurry method (1-1) comprises a step of bringing a titanium compound, a magnesium compound and the internal electron donor into contact with each other in a slurry state, at a slurry concentration of usually 0.05 to 0.7 g- solid/mL-solvent , and particularly preferably 0.1 to 0.5 g- solid/mL-solvent .

Above mechanically pulverizing method (1-2) is carried out preferably in the presence of a liquid material, in order to suppress generation of fine powder, which generation results in a solid catalyst component having an unfavorably too broad particle size distribution. Examples of the liquid material are an aliphatic hydrocarbon such as n-pentane, n-hexane, n-heptane and n-octane; ^" an aromatic hydrocarbon such as benzene, toluene and xylene; an alicyclic hydrocarbon such as cyclohexane and cyclopentane; and a halogenated hydrocarbon such as 1 , 2-dichloroethane and monochlorobenzene . Among them, particularly preferred is an aromatic hydrocarbon or a halogenated hydrocarbon.

Catalyst component production method-1 may use a compound represented by following formula (iii) in its contacting step:

M^m-cX^ . (iii) wherein M¹ is an atom of group 13 or 14; R² is a hydrocarbyl or hydrocarbyloxy group having 1 to 20 carbon atoms; X² is a halogen atom; m is a valence of M¹; and c is an integer satisfying 0 < c ≤ m.

Examples of the atom of group 13 of M¹ are boron, aluminum, gallium, indium, and thallium. Among them, preferred is boron or aluminum, and more preferred is aluminum.

Examples of the atom of group 14 of M¹ are silicon, germanium, tin, and lead. Among them, preferred is silicon, germanium or tin, and more preferred is silicon.

Examples of the hydrocarbyl group of R² are a linear or branched alkyl group such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, an n-pentyl group, an isopentyl group, an n-hexyl group, an n-heptyl. group, an n-octyl group, an n-decyl group and an n-dodecyl grouop; a cycloalkyl group such as a cyclohexyl group and a cyclopentyl group; and an aryl group such as a phenyl group, a cresyl group, a xylyl group and a naphthyl group. Examples of the hydrocarbyloxy group of R², are a linear or branched . alkoxy group such as a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, an isobutoxy group, an n-amyloxy group, an isoamyloxy group, an n-hexyloxy group, an n-heptyloxy group, an n-octyloxy group, an n-decyloxy group and an n- dodecyloxy group; a cycloalkoxy group such as a cyclohexyloxy group and a cyclopentyloxy group; and an aryloxy group such as a phenoxy group, a.xyloxy group and a naphthoxy group. Among them, preferred is an alkyl or alkoxy group having 2 to 18 carbon atoms, or an aryl or aryloxy group having 6 to 1.8 carbon atoms.

Examples of above X² are¹ a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Among them, preferred is a chlorine atom or a bromine atom.

When M¹ is an atom of group 13, m is 3. When M¹ is an atom of group 14, m is 4.

Examples of the compound represented by above formula (iii) are a chlorinated aluminum compound and a chlorinated silicon compound. Among them, preferred is ethylaluminum dichloride, ethylaluminum sesquichloride , diethylaluminum chloride, trichloroaluminum, tetrachlorosilane , phenyltrichlorosilane, methyltrichlorosilane, ethyltrichlorosilane , n-propyltrichlorosilane or p- tolyltrichlorosilane, more preferred is a chlorinated compound of an atom of group 14, and particularly preferred is tetrachlorosilane or phenyltrichlorosilane.

. When the above compound represented by formula (iii) is used, the compound is used in an amount of usually 0.1 to 1,000 mmol, preferably 0.3 to 500 mmol, and particularly preferably 0.5 to 300 mmol, per mole of a magnesium atom contained in the magnesium compound to be used. The compound represented by formula (iii). is used at one time, or in two or more batches.

Above catalyst component production method-2 is not particularly limited in its solid component, as long as the solid component contains a titanium atom and a magnesium atom.

Examples of the solid component are (i) magnesium titanate, (ii) aluminum magnesium titanate disclosed in WO2004/039747, and (iii) a solid catalyst component precursor comprising a trivalent titanium atom, a magnesium atom and a hydrocarbyloxy group. The solid catalyst component precursor (iii) is referred to hereinafter as "precursor", which means a precursor for making a solid catalyst component.

Examples of the hydrocarbyloxy group contained in the precursor are a hydrocarbyloxy groups having 1 to 20 carbon atoms. Among them, preferred is a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, an isobutoxy group, an n-pentyloxy group, a cyclopentyloxy group or a cyclohexyloxy group.

The precursor is not particularly limited in its production method. For example, it can be produced by a process comprising a step of reducing a titanium compound comprising a tetravalent titanium atom with an organomagnesium compound in the presence of a silicon compound containing a Si-0 bond. Such a -reduction step is preferably carried out by . adding the organomagnesium compound to a solution comprising the titanium compound, the silicon compound and a solvent.

Examples of the above a silicon compound are those represented by following formula (i.v) , (v) or (vi) :

R⁵ (R⁶ ₂SiO)_uSiR⁷3 (vi)

(R⁸ ₂SiO)_v (vii) wherein R³, R⁴, R⁵, R⁶, R⁷ and R⁸ are independently a hydrogen atom, or a hydrocarbyl group having 1 to 20 carbon atoms; t is an integer of 1 to 4; u is an integer of 1 to 1,000; and v is an integer of 2 to 1,000.

Examples of the hydrocarbyl group of R³ to R⁸ are an alkyl group such as a methyl group, an ethyl group, an n- propyl group, an isopropyl group, an n-butyl group, an isobutyl group, an n-pentyl group, an isopentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, an n- decyl group and an n-dodecy group; an aryl group such as a phenyl group, a cresyl group, a xylyl group and a naphthyl group; a cycloalkyl group such as a . cyclohexyl group and a cyclopentyl group; an alkenyl group such as an allyl group; and an aralkyl group such as a. benzyl group. Among them, preferred is an alkyl group having 2 to 18 carbon atoms, or an aryl group having 6 to 18 carbon atoms, and particularly preferred is a linear alkyl group having_. 2 to 18 carbon atoms.

Examples of the silicon compound represented by above respective formulae (iv) to (vi) are tetramethoxysilane, dimethyldimethoxysilane, tetraethoxysilane, triethoxyethylsilane, diethoxydiethylsilane, ethoxytriethylsilane, tetraisopropoxysilane, diisopropoxydiisopropylsilane , tetra-n-propoxysilane , di-n- propoxydi-n-propylsilane, tetra -n-butoxysilane, di-n- butoxydi-n-butylsilane, dieyclopentoxydiethylsilane , diethoxydiphenylsilane, cyclohexyloxytrimethylsilane, phenoxytrimethylsilane, tetraphenoxysilane, triethoxyphenylsilane, hexamethyldisiloxane, hexaethyldisiloxane, hexa-n-propyldisiloxane , octaethyltrisiloxane, dimethylpolysiloxane , diphenylpolysiloxane, methylhydropolysiloxane, and phenylhydropolysiloxane . Among them, preferred is a tetraalkoxysilane represented by formula (iv) having t of 4, and most preferred is tetraethoxysilane.

One example of the above titanium compound comprising a tetravalent titanium atom is a compound represented by following formula (vii) :

(vii)

wherein R⁹ is a hydrocarbyl group having 1 to 20 carbon atoms; each X³ is independently a halogen atom, or a hydrocarbyloxy group having 1 to 20 carbon atoms; and m is an integer of 1 to 20.

Examples of R⁹ are an alkyl group such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, an n-pentyl group, an isopentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, an n-decyl group and an n-dodecy group; an aryl group such as a phenyl group, a cresyl group, a xylyl group and a naphthyl group; a cycloalkyl group such as a cyclohexyl group^■ and a cyclopentyl group; an alkenyl group such as an allyl group; and an aralkyl group such as a benzyl group. Among them, preferred is an alkyl group having 2 to 18 carbon atoms, or an aryl group having 6 to 18 carbon atoms, and particularly preferred is a linear alkyl group having 2 to 18 carbon atoms, such as an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group and an isobutyl group.

Examples of the halogen atom of X³ are a chlorine atom, a bromine atom and an iodine atom. Among them, particularly preferred is a chlorine atom.

The hydrocarbyloxy group of X³ is preferably an alkoxy group having 2 to 18 carbon atoms, more preferably an alkoxy group having 2 to 10 carbon atoms, and particularly preferably an alkoxy group having 2 to 6 carbon atoms, such as an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group and an isobutoxy group.

Examples of the titanium compound represented by above formula (vii) are tetramethoxytitanium, tetraethoxytitanium, tetra-n-propoxytitanium, tetraisopropoxytitanium, tetra-n^- butoxytitanium, tetraisobutoxytitanium, n-butoxytitanium trichloride, di-n-butoxytitanium dichloride, tri-n- butoxytitanium chloride, di-n-tetraisopropylpolytitanate (mixture of compounds having "m" of 2 to 10 in formula (vii) ) , tetra-n-butylpolytitanate (mixture of compounds having "m" of 2 to 10 therein) , tetra-n-hexylpolytitanate (mixture of compounds having "m" of 2 to 10 therein), tetra-n-octylpolytitanate (mixture of compounds having ^,m" of 2 to 10 therein) , a condensation product obtained by reacting a tetraalkoxytitanium with a small amount of water, and a combination of two or more thereof. Among them, preferred is a titanium compound having "m" of 1, 2 or 4 in formula (vii) , and more preferred is tetra-n-butoxytitanium, tetra-n-butoxytitanium dimer or tetra-n-butoxytitanium tetramer. The above organomagnesium compound for producing the precursor is . not particularly limited, as long as it contains a magnesium-carbon bond (Mg-C bond). Examples thereof are those represented by following formula (viii) or (ix) , and among them, preferred is a Grignard compound represented by formula (viii) to produce the precursor having a good shape, and particularly preferred is an ether solution of a Grignard compound:

R¹⁰MgX⁴ (viii) R¹¹R¹²Mg (iX) wherein R¹⁰, R¹¹ are R¹² are independently a hydrocarbyl group having 1 to 20 carbon, atoms; and X⁴ is a halogen atom Examples of the . above hydrocarbyl group of R¹⁰ to R¹² are an alkyl group such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a n-pentyl group, an isopentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, an n- decyl group and an n-dodecyl group; an aryl group such as a phenyl group, a cresyl group, a xylyl group and a naphthyl group; a cycloalkyl group such as a cyclohexyl group and a cyclopentyl group; an alkenyl group such as an ally! group; and an aralkyl group such as a benzyl group. Among them, preferred is an alkyl group having 2 to 18 carbon atoms, or an aryl group having 6 to 18 carbon atoms, and particularly preferred is a linear alkyl group having 2 to 18 carbon atoms, such as an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group and an isobutyl group.

Examples of above X⁴. are a chlorine atom, a bromine atom and an iodine atom. Among them, particularly preferred is a chlorine atom.

Examples of the above Grignard compound are methylmagnesium chloride, ethylmagnesium chloride, n- propylmagnesium chloride, isopropylmagnesium chloride, n- butylmagnesium chloride, isobutylmagnesium chloride, tert- butylmagnesium chloride, n-pentylmagnesium chloride, isopentylmagnesium chloride, cyclopentylmagnesium chloride, n-hexylmagnesium chloride, cyclohexylmagnesium chloride, n- octylmagnesium chloride, 2-ethylhexylmagnesium chloride, phenylmagnesium chloride and benzylmagnesium chloride. Among them, preferred is ethylmagnesium chloride, n- propylmagnesium chloride, isopropylmagnesium chloride, n- butylmagnesium chloride or isobutylmagnesium chloride, and particularly preferred is n-butylmagnesium chloride.

Those Grignard compounds are used preferably as an ether solution thereof. Examples of the ether are a dialkyl ether such as diethyl ether, di-n-propyl ether, diisopropyl ether, di-n-butyl ether, diisobutyl ether, ethyl n-butyl ether and diisopentyl ether; and a cyclic ether such as tetrahydrofuran . Among them, preferred are a dialkyl ether, and particularly preferred is di-n-butyl ether or diisobutyl ether.

The above reduction step may be carried out in the presence of any ester compound. Examples of the ester compound are a monocarboxylic acid ester and a polycarboxylic acid ester. More specific examples thereof are an ester of a saturated aliphatic carboxylic acid, an ester of an unsaturated aliphatic carboxylic acid, an ester of an alicyclic carboxylic acid and an ester of an aromatic carboxylic acid. Further specific examples thereof are a compound represented by formula (I) (such as dimethyl 2,5- dioxahexanedioate and diethyl 2 , 5-dioxahexanedioate ) , methyl acetate, ethyl acetate, phenyl acetate, methyl propionate, ethyl propionate, ethyl butyrate, ethyl valerate, ethyl acrylate, methyl methacrylate, ethyl benzoate, n-butyl benzoate, methyl toluate, ethyl toluate, ethyl anisate, diethyl succinate, di-n-butyl succinate, diethyl malonate, di-n-butyl malonate, dimethyl maleate, di-n-butyl maleate, diethyl itaconate, di-n-butyl itaconate, monoethyl phthalate, dimethyl phthalate, methyl ethyl phthalate, diethyl phthalate, di-n-propyl phthalate, diisopropyl phthalate, di-n-butyl phthalate, diisobutyl phthalate, dipentyl phthalate, di-n-hexyl phthalate, di-n- heptyl phthalate, di-n-octyl phthalate, di (2-ethylhexyl) phthalate, diisodecyl phthalate, dicyclohexyl phthalate and diphenyl phthalate. Among them, preferred is a diester of an aromatic dicarboxylic acid such as a phthalic acid diester.

Examples of the above solvent to be■- used in the reduction step are an aliphatic hydrocarbon such as n- hexane, n-heptane, n-octane and n-decane; an aromatic hydrocarbon .such as toluene and xylene; an alicyclic hydrocarbon such as cyclohexane, methylcyclohexane and decalin; a dialkyl ether such as diethyl ether, di-n-propyl ether, diisopropyl ether, di-n-butyl ether, diisobutyl ether, ethyl-n-butyl ether and diisopentyl ether; a cyclic ether such as tetrahydrofuran; a halogenated aromatic compound such as chlorobenzene and dichlob.enzene; and a combination of two or more thereof. Among them, preferred is an aliphatic hydrocarbon, an aromatic hydrocarbon or an alicyclic hydrocarbon, more preferred is an aliphatic hydrocarbon or an alicyclic hydrocarbon, further^■ preferred is an aliphatic hydrocarbon, and particularly preferred is n-hexane or n-heptane.

The reduction step uses the silicon compound in an amount of usually 1 to 500 mol, preferably 1 to 300 mol, and particularly preferably 3 to 100 mol per mole of the titanium atom contained in the titanium compound to be used, expressed by the molar number of the silicon atom contained in the silicon compound to be^" used.

The reduction step uses the organomagnesium compound in an amount of usually 0.1 to 10 mol, preferably 0.2 to 5.0. mol, and particularly preferably 0.5 to 2.0 mol per mole of the total of the titanium atom contained in the titanium compound to be used and the silicon atom contained in the silicon compound to be used.

Alternatively, the reduction step uses the titanium compound, the silicon compound and the organomagnesium compound in their amount, such that an obtained precursor contains a magnesium atom in an amount of usually 1 to 51 mol, preferably 2 to 31 mol, and particularly preferably 4 to 26 mol, per one mol of a titanium atom contained in the precursor.

When the reduction step uses the above ester compound, the reduction step uses the ester compound in an amount of usually 0.05 to 100 mol, preferably 0.1 to 60 mol,_. and particularly preferably 0.2 to 30 mol, per mole of the titanium atom contained in the titanium compound to be used

The organomagnesium compound is added to a solution comprising the titanium compound and silicon compound, at usually -50 to 100°C, preferably -30 to 70°C, and particularly preferably -25 to 50°C, over an unrestricted time, usually over about 30 minutes to about 6 hours. The organomagnesium compound is added thereto preferably continuously in order to produce a precursor having a good shape. The reaction ^' mixture obtained in the reduction step may be further heated at 5 to 120°C to promote the reduction reaction.

The reduction step may be carried out in the presence of a carrier in order to support a resultant precursor on' the carrier. The carrier is not particularly limited in its kind Examples of the carrier are a porous inorganic oxide such as Si0₂, AI2O3, MgO, Ti0₂ and Zr0₂; and a porous organic polymer such as polystyrene, _. a styrene- divinylbenzene copolymer, a copolymer of styrene with a monomer, CH₂=C (CH₃) COO-CH₂CH₂-OCOC (CH₃) =CH₂, obtained by a reaction between ethylene glycol and methacrylic acid, polymethyl acrylate, polyethyl acrylate, a methyl acrylate- divinylbenzene copolymer, polymethyl methacrylate, a methyl methacrylate-divinylbenzene copolymer, polyacrylonitrile, an acrylonitrile-divinylbenzene copolymer, polyvinyl chloride, polyethylene and polypropylene. Among them, preferred is a porous organic polymer, . and particularly preferred is a styrene-divinylbenzene copolymer .

In order to support a precursor effectively on a carrier, the carrier has a pore volume of preferably 0.3 cm³/g or more, and more preferably 0.4 cm³/g or more, in a pore radius range of 20 to 200 nm, a proportion of which pore volume is preferably 35% or more, and more preferably 40% or more, provided that a proportion of a pore volume in a pore radius range of 3.5 to 7,500 nm is 100%. In the reduction step, a tetravalent titanium atom contained in the titanium compound represented by formula (vii) is reduced to a trivalent titanium atom. It is preferable in the present invention that substantially all tetravalent titanium atoms contained in the titanium compound be reduced to trivalent titanium atoms. The obtained precursor contains a trivalent titanium atom, a magnesium atom and a hydrocarbyloxy group, and is generally amorphous or extremely week crystalline. Among them, preferred is an amorphous precursor.

The obtained precursor may be washed with a solvent. Examples of the solvent are an aliphatic hydrocarbon such as n-pentane, n-hexane, n-heptane, n-octane and n-decane; an. aromatic hydrocarbon such as benzene, toluene, ethylbenzene and xylene; an alicyclic hydrocarbon such as cyclohexane and cyclopentane ; and a halogenated hydrocarbon such as 1, 2-dichloroethane and monochlorobenzene . Among them, preferred is an aliphatic hydrocarbon or an aromatic hydrocarbon, more preferred is an aromatic hydrocarbon, and particularly preferred is toluene or xylene.

Sub-step (2) of catalyst component production method-2 uses an internal electron donor represented by formula (I) in an amount of usually 0.1 to 1,000 mol, preferably 0.3 to 500 mol, and particularly preferably 0.5 to 300 mol, per gram of the solid component (precursor) . The internal electron donor is used at one time, or in two or more batches.

Sub-step (2) of catalyst component production method-2 is not particularly limited in its contact temperature and time, the contact temperature being usually -50 to 200°C, preferably 0 to 170°C, more preferably 50 to 150°C, and particularly preferably 50 to 120°C, and the contact time being usually 10 minutes to 12 hours, preferably 30 minutes to 10 hours, and particularly preferably 1 to 8 hours. The "contact time" in the present invention is defined as follows: when bringing a titanium compound, a magnesium compound and the internal electron donor simultaneously into contact with each other, the "contact time" means a time for which such a simultaneous contact is carried out, and when contacting them stepwise, the "contact time" means the total of times for which respective contacts are carried out.

Sub-step (2) of catalyst component production method-2 may use a halogen-containing compound represented by following formula (x) :

M²R¹³ _m_cX⁵c (x) wherein M² is an atom of group 4, 13 or 14; R¹³ is independently a hydrocarbyl or hydrocarbyloxy group having 1 to 20 carbon atoms; X⁵ is a halogen atom; m is a valence of M²; and c is a number satisfying 0 < c ≤ m. Examples of the above atom of group 4 of M² are a titanium atom, a zirconium atom and a hafnium atom. Among them, preferred is a titanium atom. Examples of the above atom of group 13 of M² are a boron atom, an aluminum atom, a gallium atom, an indium atom and a thallium atom. Among them, preferred is a boron atom or an aluminum atom, and more preferred is an aluminum atom. Examples of the above atom of group 14 of M² are a silicon atom, a germanium atom, a tin atom and a lead atom. Among them, preferred is a silicon atom, a germanium atom or a - tin atom, and more preferred is a silicon atom.

Examples of the above hydrocarbyl group of R¹³ are a linear or branched alkyl group such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n- butyl group, an isobutyl group, an n-pentyl group, an isopentyl group, an n-hexyl group, an n-heptyl group, an n- ^"octyl group, an n-decyl group and an n-dodecyl group; a cycloalkyl group such as a cyclohexyl group and a cyclopentyl group; and an aryl group^' such as a phenyl group, a cresyl group, a xylyl group and a naphthyl group.

Examples of the above hydrocarbyloxy group of R¹³ are a linear or branched alkoxy group such as a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, an isobutoxy group, an n-amyloxy group, an isoamyloxy group, an n-hexyloxy group, an n-heptyloxy group, an n-octyloxy group, an n-decyloxy group and an n- dodecyloxy group; a cycloalkoxy group such as a cyclohexyloxy, group and a cyclopentyloxy group; and an aryloxy group such as a phenoxy group, a xyloxy group and a naphthoxy group.

Among them, R¹³ is preferably an alkyl or alkoxy group having 2 to 18 carbon atoms, or an aryl or aryloxy group having 6 to 18 carbon atoms.

Examples of above X⁵ are a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. Among them, preferred is a chlorine atom or a bromine atom.

When above M² is an atom of group 4 or 14, m is 4, and c is an_. integer satisfying 0 < c ≤ 4, preferably 3 or 4, and more preferably 4. When ² is an atom of group 13, m is 3, and c is an integer satisfying 0 < c ≤ 3, and preferably 3.

Examples of the above halogen-containing compound represented by formula (x) are titanium compounds disclosed in U.S. Patent No. 6,187,883, and chlorinating agents of group 13 or 14 disclosed in U.S. Patent No. 6,903,041.

A halogen-containing titanium compound of the halogen- containing compound represented by above formula (x) is preferably a titanium tetrahalide such as titanium tetrachloride, titanium tetrabromide and titanium tetraiodide; or an alkoxytitanium trihalide such _. as methoxytitanium trichloride, ethoxytitanium trichloride, butoxytitanium trichloride, phenoxytitanium trichloride and ethoxytitanium tribromide, more preferably a titanium tetrahalide, and particularly preferably titanium tetrachloride.

A chlorine-containing compound of an atom of group 13 or 14 of the halogen-containing compound represented by above formula (x) is preferably ethylaluminum dichloride, ethylaluminum sesquichloride, diethylaluminum chloride, trichloaluminum, tetrachlorosilane, phenyltrichlorosilane , methyltrichlorosilane, ethyltrichlorosilane, n- propyltrichlorosilane or p-tolyltrichlorosilane ; more preferably a chlorine-containing compound of an atom of group 14; and particularly preferably tetrachlorosilane or phenyltrichlorosilane .

When sub-step (2) of catalyst component production method-2 uses a halogen-containing compound represented by formula (x) , sub-steps (2) uses the halogen-containing compound in an amount of usually 0.1 to 1,000 mmol, preferably 0.3 to 500 mmol, and particularly preferably 0.5 to 300 mmol, per gram of the solid component (precursor) . The halogen-containing compound is used at one time, or in two or more batches.

Sub-step (2) of catalyst component production method-2 is not particularly limited in its contact method. Examples thereof are those known in the art such as (2-1) a slurry method, and (2-2) a mechanically pulverizing method using a ball mill. ^"Mechanically pulverizing method (2-2) is carried out preferably in the presence of the above- mentioned liquid material, in order to suppress generation of fine powder, which generation results in a solid catalyst component having an unfavorably too broad particle size distribution.

Above slurry method (2-1) comprises a step of bringing a solid component (precursor) , an internal electron donor represented by formula (I) and, optionally, a halogen- containing compound represented by above formula (x) into contact with each other in a slurry state, at a slurry concentration of usually 0.05 to 0.7 g-solid/mL-solvent , and particularly preferably 0.1 to 0.5 g-solid/mL-solvent. Its contact temperature is not particularly limited, and is usually 30 to 150°C, preferably 45 to 135°C, and particularly preferably 60 to 120°C. Its contact time is not particularly limited, and preferably is usually about 30 minutes to about 6 hours.

The above-mentioned solid catalyst component is brought into contact with an organoaluminum compound and, optionally, an external electron donor to make a solid catalyst, wherein its contact method may be known in the art .

Examples of the organoaluminum compound are those disclosed in above-mentioned U.S. Patent No. 6,903,041. Among them, preferred is a trialkylaluminum, a mixture of a trialkylaluminum with a dialkylaluminum halide, or an alkylalumoxane, and further preferred is triethylaluminum, triisobutylaluminum, a mixture of triethylaluminum with diethylaluminum chloride, or tetraethyldialumoxane .

Examples of the above external electron donor are those disclosed in above-mentioned U.S. Patent No. 6,903,041. . Among them, preferred is an oxygen-containing compound or a nitrogen-containing compound. Examples of the oxygen-containing compound are an alkoxysilicon, an ether, an ester and a ketone. Among them, preferred is an alkoxysilicon or an ether. Those external electron donors are used alone, respectively, or in combination of two or more thereof. .

The above external electron donor is preferably a cyclic ether. Among them, preferred is a cyclic ether containing one or more -C-O-C- bonds in its cyclic structure, and more preferred is a cyclic ether containing one or more -C-O-C- O-C- bonds in its cyclic structure. Examples of the cyclic ether are 1 , 3-dioxolane and 1,3-dioxane.

The process for ·. producing a solid catalyst of the present invention is not particularly limited in its method for bringing the solid catalyst component, the organoaluminum compound and, optionally, the external electron donor into contact with each other, as long as a solid catalyst is produced. Such a. contact is carried out with or without the use of a solvent. Examples of a method for feeding the solid catalyst component, the organoaluminum compound and the external electron donor to a polymerization reactor are (i) a method^■- comprising steps of bringing all of them^" into contact with each other to form a contact product, and feeding the contact product to the polymerization reactor, (ii) a method comprising a step of feeding them separately to the polymerization reactor, thereby bringing them into contact with each other in the polymerization reactor, and (iii) a method comprising steps of bringing any two of them into contact with each other to form a contact product, and feeding the contact product and the remaining compound ^* or external electron donor separately to the polymerization reactor, thereby bringing them into contact with each other therein.

Examples of the olefin to be used in the process for ^•producing an olefin polymer of the present invention are ethylene and an a-olefin having three or more carbon atoms. Examples of the a-olefin are a linear mono-olefin such as propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1- octene and 1-decene; a branched mono-olefin such as 3- methyl-l-butene, 3-methyl-l-pentene and 4-methyl-l-pentene; a cyclic mono-olefin such as vinylcyclohexane; and a combination of two or more of those olefins. Among olefin polymers produced in the present invention, preferred is a homopolymer of ethylene or propylene, or a copolymer of ethylene or propylene with other one or more . olefins containing an ethylene unit or a propylene unit as a major monomer unit, and more preferred is a copolymer containing 50% by weight or more of an ethylene unit, provided that the total of the copolymer is 100% by weight. The above copolymer ^" may contain a monomer unit derived from two or more monomers containing an unsaturated bond such as a conjugated diene and an unconjugated diene.

An olefin polymer produced by the process of the <^~ present invention is preferably a homopolymer of ethylene, propylene, 1-pentene, 1-pentene or 1-hexene, an ethylene- propylene copolymer, an ethylene-l-butene copolymer, an ethylene-l-hexene copolymer, a propylene-l-butene copolymer, a propylene-l-hexene copolymer, an ethylene-propylene-1- butene copolymer, an ethylene-propylene-l-hexene copolymer, and a so-called block copolymer (or impact copolymer) produced by a polymerization method comprising steps of (i) polymerizing an olefin, thereby producing a homopolymer of the olefin, and (ii) copolymerizing two or more olefins in the presence of the homopolymer.

In some cases, the solid catalyst in the present invention is preferably a solid catalyst produced by a process comprising steps of:

(1) polymerizing a small amount of an olefin in the presence of the above solid catalyst component, the above organoaluminum compound and, optionally, the external electron donor, thereby producing a pre-polymerized catalyst component; and

(2) bringing the pre-polymerized catalyst component, an organoaluminum compound and, optionally, the external electron donor into contact with each other, thereby producing a solid catalyst;

wherein (i) the pre-polymerized catalyst component is solid catalyst component whose surface is. covered with an olefin polymer formed in step (1), (ii) the term "pre-polymerized" (pre-polymerization) contained in the term "pre-polymerized catalyst component" is used in order to distinguish from polymerization carried out in the process for producing an olefin, polymer of the present invention, the latter polymerization being referred to as "main polymerization" by those skilled in the art, (iii) the olefin used in step (1) is the same as, or different from an olefin used in the main polymerization, and (iv) step (1) may use a chain- transfer agent such as hydrogen in order to regulate a molecular weight of an olefin polymer formed in step (1), and may use an external electron donor. Such pre- polymerization is disclosed in JP11-322833A. Based on the above, a solid catalyst to be used in the present invention can be produced by (I) a process comprising a step of bringing the above solid catalyst component, an organoaluminum compound and, optionally, the external electron donor into contact with each other, or (II) a process comprising a step of bringing the above pre- polymerized catalyst component, an organoaluminum compound and, optionally, the external electron donor into contact with each other. Therefore, the process for producing a solid catalyst of the present invention means not only above process (I), but also above process (II). Accordingly, the process for producing an olefin polymer of the present invention means not only a process using a solid catalyst produced by above process (I), but also a process using a solid catalyst produced by above process (II) . Also, a solid catalyst used in the process for , producing an olefin polymer of the present invention may be a combination of a solid catalyst produced by above process (I) with a solid catalyst produced by above process (II) .

The above pre-polymerization is preferably slurry polymerization using an inert hydrocarbon solvent, such as n-propane, n-butane, isobutane, n-pentane, isopentane, n- hexane, n-heptane, n-octane, cyclohexane, benzene and toluene. A slurry concentration of a solid catalyst component is preferably 1 to 500 g-solid catalyst component/liter-solvent , and particularly preferably 3 to 300 g-solid catalyst component/liter-solvent .

An organoaluminum_. compound in above step (1) is used in an amount of usually 0.5 to 700 mol, preferably 0.8 to 500 mol, and particularly preferably 1 to 200 mol, per mole of the titanium atom contained in the solid catalyst component .

An olefin in above step (1) is used in an amount of usually 0.01 to 1,000 g, preferably 0.05 to 500 g, and particularly preferably 0.1 to 200 g, per gram of the solid catalyst component .

Above step (1) is carried out at preferably -20 to 100°C, and particularly preferably 0 to 80°C, for an unrestricted time, preferably for 2 minutes to 15 hours, and under a partial pressure of an olefin in a gas phase of preferably 0.01 to 2 Pa, and particularly preferably 0.1 to 1 MPa, provided that an olefin having a liquid state under the above temperature and pressure is not limited thereto.

Examples of a method for feeding a solid catalyst component, an organoaluminum compound and an olefin to a pre-polymerization reactor are . (i) a method comprising steps of feeding . the solid catalyst component and organoaluminum compound, and then feeding the olefin, and (ii) a method comprising steps of feeding the solid catalyst component and olefin, and then feeding the organoaluminum compound.

Examples of a method for feeding an olefin to a pre- polymerization reactor are (i) a method of feeding the olefin sequentially to the pre-polymerization reactor, so as to keep an internal pressure of the pre-polymerization reactor at a predetermined level, and (ii) a method of feeding thereto a prescribed total amount of the olefin at a time.

The external electron donor in above step (1) is optionally used in an amount of generally 0.01 to 400 mol, preferably 0.02 to 200 mol, and particularly preferably 0.03 to 100 mol, per mole of the titanium atom contained in the solid catalyst component, and is used in an amount of generally 0.003 to 5 mol, preferably 0.005 to 3 mol, and particularly preferably 0.01 to 2 mol, per mole of the organoaluminum compound.

Examples of a method for feeding the external electron donor to a pre-polymerization reactor in above step (1) are (i) a method of feeding the external electron donor alone to the pre-polymerization reactor, and (ii) a method of. feeding a contact product of the external electron donor with the organoaluminum compound to the pre-polymerization reactor.

The organoaluminum compound in the process for producing a solid catalyst of the present invention is used in an amount of usually 1 to 1, 000 mol, and particularly preferably 5 to 600 mol, per mole of the titanium atom contained in the solid catalyst component.

The external electron donor in the process for producing a solid catalyst of the present invention is used in an amount of usually 0.1 to 2,000 mol, preferably 0.3 to 1,000 mol, and particularly preferably 0.5 to 800 mol, per mole of the titanium atom contained in the solid catalyst component, or is used in an amount of usually 0.001 to 5 mol, preferably 0.005 to 3 mol, and particularly preferably 0.01 to 1 mol, per mole of the organoaluminum compound.

The process for producing an olefin polymer of the present invention is carried out batch-wise or continuously, (1) at usually -30 to 300°C, and preferably 20 to 180°C, (2) under a pressure, which is not particularly restricted, of usually atmospheric pressure to 10 MPa, and preferably 200 kPa to 5 MPa, from an industrial and economical point of view, (3) according to (3-1) a slurry or solution polymerization method with the use of an inert hydrocarbon solvent such as n-propane, n-butane, isobutane, n-pentane, n-hexane, n-heptane and n-octane, (3-2) a bulk polymerization method using ah olefin as a solvent, which is liquid at polymerization temperature, or (3-3) a gas- phase polymerization method, and (4) with or without the use of a chain transfer agent such as hydrogen and an alkyl zinc (for example, dimethyl zinc and diethyl zinc) in order to control a molecular weight of an olefin polymer produced According to the present invention, there can be provided (1) a solid catalyst component which has a high polymerization activity, and gives an olefin polymer containing only a small amount of a component soluble in an organic solvent at low temperature, (2) a process for producing such a solid catalyst component, (3) a process for producing a solid catalyst, and (4) a process for producing an olefin polymer.

Example

The present invention is explained in more detail with reference to the following Example.

Example 1

(1) production of solid catalyst component precursor

There were added 270 mL of hexane, 79.9 mL of tetraethoxysilane and 8.1 mL of tetra-n-butoxytitanium to a reactor purged with nitrogen and equipped with a stirrer. While stirring the resultant mixture at 5°C, 182 mL of a di-n-butyl ether solution (concentration: 2.1 mol/L) of n- butylmagnesium chloride was added dropwise to the mixture over 4 hours. The mixture was warmed up to 20°C, and then was stirred at 20°C for 1 hour. The reaction mixture was subjected to solid-liquid separation. The separated solid was washed three times with each 280 mL of toluene, thereby obtaining a solid catalyst component precursor. The precursor was slurried with 136 mL of toluene, thereby obtaining toluene slurry of the precursor.

(2) Production of solid catalyst component

A 100 mL flask equipped with a stirrer, a dropping funnel and a thermometer was purged with nitrogen. The above toluene slurry was added to the flask in an amount containing 7 g of the precursor. An additional amount of toluene was added thereto, thereby obtaining 40.6 mL of the toluene slurry. Then, 2.0 mL of diethyl 2,5- dioxahexanedioate and 5.4 mL of phenyltrichlorosilane were added to the flask, and the resultant mixture was stirred at 105°C for 3 hours. The obtained mixture was subjected to solid-liquid separation. The separated solid was washed at 105°C three times with each 30 mL of toluene. The washed solid was combined with 20 mL of toluene. The obtained mixture was heated up to 70°C, and 3.5 mL of titanium tetrachloride was added thereto. The resultant mixture was stirred at 105°C for one hour. The obtained mixture was subjected to solid-liquid separation. The separated solid was washed at 105°C six times with each 30 mL of toluene. The washed solid was further washed three times with each 30 mL of hexane . The washed solid was dried, thereby obtaining a solid catalyst component.

(3) Copolymerization of ethylene with 1-butene

A 3 liter autoclave equipped with a stirrer was dried thoroughly, and was evacuated. Then, 0.087 MPa of hydrogen, 640 g of butane and 110 g of 1-butene were added to the autoclave in this order, and the mixture was heated up to 70°C. Ethylene was added thereto in its partial pressure of 0.6 MPa. Then, 5.7 mmol of triethylaluminum and 2.88 mg of the above-obtained solid catalyst component were pressed into the autoclave, thereby initiating copolymerization.

The copolymerization was carried out at 70°C for 120 minutes under feeding ethylene continuously and keeping the total pressure constant, Unreacted monomers remaining in the . autoclave were purged, thereby obtaining 35 g of an ethylene-l-butene copolymer excellent in its powder property. The inner wall of the autoclave and the stirrer scarcely had a polymer adhered thereto.

Its polymerization activity was calculated to be 12,200 g- copolymer/g-solid catalyst component. The ethylene-1- butene copolymer was found to have a short chain branch (SCB) of 12.9, and a cold-xylene soluble part (CXS) of 3.7% by_. weight. Results are shown in Table 1. The above short chain branch (SCB) (unit: CH₃/1,000C), which means the number of a methyl group per 1,000 carbon atoms contained in the obtained copolymer, was measured from characteristic absorptions of ethylene and 1-butene assigned in an infrared absorption spectrum measured with an infrared spectrophotometer, FT/IR-470 PLUS, manufactured by Japan Spectroscopic Co., Ltd., using a calibration curve

The above cold-xylene soluble part (CXS), which means an amount of a soluble part in xylene at 20°C, was measured by the following method comprising steps of:

(i) adding 1 g of a polymer to 200 mL of boiling xylene, thereby obtaining a solution;

(ii) cooling the solution slowly down to 50°C;

(iii) further, cooling the solution under stirring down to 20°C by dipping it in an iced water bath;

(iv) keeping the solution at 20°C for three hours, thereby precipitating a polymer;

(v) filtering off the precipitated polymer, thereby obtaining a filtrate;

(vi) distilling away xylene contained in the filtrate to dryness, thereby obtaining a soluble part;

(vii) weighing the soluble part; and

(viii) calculating CXS (% by weight) based thereon, provided, that .the total of the used polymer is 100% by weight. Comparative Example 1

(1) Production of solid catalyst component

, Example 1_.(2) was repeated except that 2.0 mL of diethyl 2, 5-dioxahexanedioate was changed to 3.0 mL of ethylene carbonate, thereby obtaining a solid catalyst component .

(2) Copolymerization of ethylene with 1-butene

Example 1(3) was repeated except that 2.88 mg of the solid catalyst component was changed to 6.91 mg_ of the above-obtained solid catalyst component, thereby obtaining 4 g of an ethylene-l-butene copolymer.

Its polymerization activity was calculated to be 600 g-copolymer/g-solid catalyst component. Its yield was so poor that its property such as SCB and CXS could not be measured. Results are shown in Table 2.

Comparative Example 2

(1) Production of solid catalyst component

Example 1(2) was repeated except that 2.0 mL of diethyl 2 , 5-dioxahexanedioate was changed to 1.0 mL of propylene carbonate, thereby obtaining a solid catalyst component .

(2) Copolymerization of ethylene with 1-butene

Example 1(3) was repeated except that 2.88 mg of the solid catalyst component was changed to 4.10 mg of the above-obtained solid catalyst component, thereby obtaining 9 g of an ethylene-l-butene copolymer.

Its polymerization activity was calculated to be 2,200 g-copolymer/g-solid catalyst component. The ethylene-l- butene copolymer was found to have an SCB of 12.4, and a CXS of 5.3% by weight. Results are shown in Table 2.

Comparative Example 3

(1) Production of solid catalyst component

Example 1(2) was repeated except that 2.0 mL of diethyl 2 , 5-dioxahexanedioate was changed to 1.0 mL of butylene carbonate, thereby obtaining a solid catalyst component .

(2) Copolymerization of ethylene with 1-butene

Example 1(3) was repeated except that 2.88 mg of the solid catalyst component was changed to 3.60 mg of the above-obtained solid catalyst component, thereby obtaining 21 g of an ethylene-l-butene copolymer.

Its polymerization activity was calculated to be 5,800 g-copolymer/g-solid catalyst component. The ethylene-l- butene copolymer was found to have an SCB of 16.2, and a CXS of 7.3% by weight. Results are shown in Table 2. Example 2 (1) Production of solid catalyst component

A 100 mL flask equipped with a stirrer, a dropping funnel and a thermometer was purged with nitrogen. The above toluene slurry of the precursor obtained in Example 1(1) was added to the flask in an amount containing 7 g of the precursor. An additional amount of toluene was added thereto, thereby obtaining 40.6 mL of the toluene slurry. Then, 1.1 mL of diethyl 2 , 5-dioxahexanedioate and 3.5 mL of phenyltrichlorosilane were added to the flask, and the resultant mixture was stirred at 100°C for 3 hours. The obtained mixture was subjected to solid-liquid separation. The separated solid was washed at 105°C three times with each 30 mL of toluene. The washed solid was combined with 30 mL of toluene. The obtained mixture was heated up to 70°C, and 2.5 mL of titanium tetrachloride was added thereto. The resultant mixture was stirred at 100°C for one hour. The obtained mixture was subjected to solid- liquid separation. The separated solid was washed at 105°C six times with each 30 mL of toluene. The washed solid was further washed three times with each 30 mL of hexane . The washed solid was dried, thereby obtaining a solid catalyst component .

(2) Copolymerization of ethylene with 1-butene

Example 1(3) was repeated except that 2.88 mg of the solid catalyst component was changed to 7.68 mg of the above-obtained solid catalyst component, thereby obtaining 100 g of an ethylene-l-butene copolymer.

Its polymerization activity was calculated to be 13,000 g-copolymer/g-solid catalyst component. The ethylene-l-butene copolymer was found to have an SCB of 13.8, and a CXS of 3.2% by weight. Results are shown in Table 1.

Example 3

(1) Production of solid catalyst component

A 100 mL flask equipped with a stirrer, a dropping funnel and a ^"thermometer was purged with nitrogen. The above toluene slurry of the precursor obtained in Example 1(1) was added to the flask in an amount containing 7 g of the precursor. An additional amount of toluene was added thereto, thereby obtaining 40.6 mL of the toluene slurry. Then, 1.4 mL of diethyl 2 , 5-dioxahexanedioate and 3.5 mL of phenyltrichlorosilane were added to the flask, and the resultant mixture was stirred at 100°C for 2 hours. The obtained mixture was subjected to solid-liquid separation.

The separated solid was washed at 105°C three times with each 30 mL,of toluene. The washed solid was combined with 30 mL of toluene. The obtained mixture was heated up to 70°C, and 3.5 mL of titanium tetrachloride was added thereto. The resultant mixture was stirred at 110°C for three hours. The obtained mixture was subjected to solid- liquid separation. The separated solid was washed at 105°C six times with each 30 mL of toluene. The washed solid was further washed three times with each 30 mL of hexane . The washed solid was dried, thereby obtaining a solid catalyst component .

(2) Copolymerization of ethylene with 1-butene

Example 1(3) was repeated except that 2.88 mg of the solid catalyst component was changed to 10.87 mg of the above-obtained solid catalyst component, thereby obtaining

136 g of an ethylene-l-butene copolymer.

Its polymerization activity was calculated to be

12,500 g-copolymer/g-solid catalyst component. The ethylene-l-butene copolymer was found to have an SCB of 14.2, and a CXS of 4.8% by weight. Results are shown in

Table 1.

Example 4

(1) Production Of solid catalyst component

A 100 mL flask equipped with a stirrer, a dropping funnel and a thermometer was purged with nitrogen. The above toluene slurry of the precursor obtained in Example 1(1) was added to the flask in an amount containing 7 g of the precursor. An additional amount of toluene was added thereto, thereby obtaining 40.6 mL of the toluene slurry. Then, 1.7 mL of diethyl 2 , 5-dioxahexanedioate and 5.3 mL of phenyltrichlorosilane were added to the flask, and the resultant mixture was stirred at 110°C for 2 hours. The obtained mixture was subjected to solid-liquid separation. The separated solid- was washed at 105°C three times with each 30 mL of toluene. The washed solid was combined with 30 mL of toluene. The obtained mixture was heated up to 70°C, and 2.5 mL of titanium tetrachloride was added thereto. The resultant . mixture was stirred at 110°C for one hour. The obtained mixture was subjected to solid- liquid separation. The separated solid was washed at 105°C six times with each 30 mL of toluene. The washed solid was further washed three times with each 30 mL of hexane . The washed solid was dried, thereby obtaining a solid catalyst component.

(2) Copolymerization of ethylene with 1-butene

Example 1(3) was repeated except that 2.88 mg of the solid catalyst component was changed to 8.90 mg of the above-obtained solid catalyst component, thereby obtaining 36 g of an ethylene-l-butene copolymer.

Its polymerization activity was calculated to be 4,000 g-copolymer/g-solid catalyst component. The ethylene-l- butene copolymer was found to have an SCB of 13.3, ^' and a CXS of 3.6% by weight. Results are shown in Table 1. Example 5

(1) Production of solid catalyst component

A 100 mL flask equipped with a stirrer, a dropping funnel and a thermometer was purged with nitrogen. The above toluene slurry of the precursor obtained in Example 1(1) was added to the flask in an amount containing 7._. g of the precursor. An additional amount of toluene was added thereto, thereby obtaining 40.6 mL of the toluene slurry. Then, 1.7 mL of diethyl 2 , 5-dioxahexanedioate and 3.5 mL of phenyltrichlorosilane were added to the flask, and the resultant mixture was stirred at 105°C for one hour. The obtained mixture was subjected to solid-liquid separation. The separated solid was washed at 105°C three times with each 30 mL of toluene. The washed solid was combined with 30 mL of toluene. The obtained mixture was heated up to 70°C, and 4.5 mL of titanium tetrachloride was added thereto. The resultant mixture was stirred at 105°C for three hours. The obtained mixture was subjected to solid- liquid separation. The separated solid was washed at 105°C six times with each 30 mL of toluene. The washed solid was further washed three times with each 30 mL of hexane . The washed solid was dried, thereby obtaining a solid catalyst component .

(2) Copolymerization of ethylene with 1-butene

Example 1(3) was repeated except that 2.88 mg of the solid catalyst component was changed to 8.53 mg of the above-obtained solid catalyst component, thereby obtaining 87 g of an ethylene-l-butene copolymer.

Its polymerization activity was calculated- to be 10,200 g-copolymer/g-solid catalyst component. The ethylene-l-butene copolymer was found to have an SCB of 13.6, and a CXS of 4.2% by weight. Results are shown in Table 1. Example 6

(1) Production of solid catalyst component

A 100 mL flask equipped with a stirrer, a dropping funnel and a thermometer was purged with nitrogen. There were put 5.0 g of diethoxymagnesium and 35 mL of toluene in the flask. The flask was heated up to 70°C, and then 5.4 mL of phenyltrichlorosilane and 2.8 mL of diethyl 2,5- dioxahexanedioate were added thereto. The resultant mixture was stirred at 105°C for three, hours. The obtained mixture was subjected to solid-liquid separation. The separated solid was washed at 105°C three times with each 30 mL of toluene. The washed solid was combined with 30 mL of toluene. The obtained mixture was heated up to 70°C, and 7.0 mL of titanium tetrachloride was added thereto. The resultant mixture was stirred at 105°C for one hour. The obtained mixture was subjected to solid-liquid separation. The separated solid was washed at 105°C six times with each 30 mL of toluene. The. washed solid was further washed three times with each 30 mL of hexane at room temperature. The washed solid was dried., thereby obtaining a solid catalyst component.

(2) Copolymerization of ethylene with 1-butene

Example 1(3) was repeated except that 2.88 mg of the solid catalyst component was changed to 16.50 mg of the above- obtained solid catalyst component, thereby obtaining 61 g of an ethylene-l-butene copolymer.

Its polymerization activity was calculated to be 3,700 g-copolymer/g-solid catalyst component. The ethylene-l- butene copolymer was found to have an SCB of 16.1, and a CXS of 7.7% by weight. Results are shown in Table 1.

t

Example 7

(1) Production of solid catalyst component

A 100 mL flask equipped with a stirrer, a dropping funnel and a thermometer was purged with nitrogen. There were put 5.1 g of magnesium chloride, 23.0 mL of decane and 25.06 mL of 2-ethylhexanol in the flask. The resultant mixture was stirred at 120°C for two hours. The flask was cooled down to 60°C, and then 1.28 mL of diethyl 2,5- dioxahexanedioate was added thereto. The resultant mixture was stirred at 120°C for two hours. The obtained homogeneous solution was cooled down to room temperature. All of the homogeneous solution was added dropwise to 127.8 mL of titanium tetrachloride maintained at -20°C under stirring. The obtained liquid mixture was heated up to 110°C over five hours, and then 0.8 mL of diethyl 2,5- dioxahexanedioate was added thereto. The mixture was heated at 110°C for two hours, and the resultant reaction mixture was subjected to solid-liquid separation. The separated solid was suspended in 178.9 mL of titanium tetrachloride. The suspension liquid was heated at 110°C for two hours, and then the obtained reaction mixture was subjected to solid-liquid separation by means of thermal filtration. The obtained solid was washed at 105°C ten times with each 30 mL of decane. The washed solid was further washed two times with each 30 mL of hexane at room temperature. The washed solid was dried, thereby obtaining a solid catalyst component.

(2) Copolymerization of ethylene with 1-butene

Example 1(3) was repeated except that 2.88 mg of the solid catalyst component was changed to 11.10 mg of the above-obtained solid catalyst component, thereby obtaining 202 g of an ethylene-l-butene copolymer.

Its polymerization activity was calculated to . be 18,200 g-copolymer/g-solid catalyst component. The ethylene-l-butene copolymer was found to have an SCB of 16.7, and . a CXS of 9.7% by weight. Results are shown in Table 1.

Comparative Example 4

(1) Copolymerization of ethylene with 1-butene

Example 1(3) was repeated except that 2.88 mg of_. the solid catalyst component was changed to 19.90 mg of the solid catalyst component obtained in Comparative Example 3(1), 640 g of butane was changed to 660 g of butane, and 110 g of 1-butene was changed to 90 g of 1-butene, thereby obtaining 106 g of an ethylene-l-butene copolymer.

Its polymerization activity was calculated to be 5,300 g-copolymer/g-solid catalyst component. The ethylene-l- butene copolymer was found to have an SCB of 14.5, and a CXS of 6.7% by weight. Results are shown in Table 2.

Comparative Example 5

(1) Copolymerization of ethylene with 1-butene

Example 1(3) was repeated except that 2.88 mg of the solid catalyst component was changed to 18.70 mg of the solid catalyst component obtained in Comparative Example 3(1), 640 g of butane was changed to 670 g of butane, and 110 g of 1-butene was changed to 70 g of 1-butene, thereby obtaining 75 g of an ethylene-l-butene copolymer.

Its polymerization activity was calculated to be 4,000 g^copolymer/g-solid catalyst component. The ethylene-1- butene copolymer was found to have an SCB of 12.4, and a CXS -of 5.1% by weight. Results are shown in Table 2.

Table 1

Note: EC, PC and BC mean ethylene carbonate, propylene carbonate and butylene carbonate, respectively. Table 2

Note: EC, PC and BC mean ethylene carbonate, propylene carbonate and butylene carbonate, respectively.

Claims

1. A solid catalyst component for olefin polymerization comprising a titanium atom, a magnesium atom, a halogen atom, and an internal electron donor represented by formula (I):

(I) wherein each R is independently, an optionally substituted hydrocarbyl group having 1 to 20 carbon atoms, or the two R groups are linked together to form a ring; each X is independently an oxygen atom or a sulfur atom; Z is an optionally substituted hydrocarbylene group having 1 to 20 carbon atoms; and n is an integer of 1 to 100.

2. The solid catalyst component according to claim 1, wherein X in formula (I) is an oxygen, atom.

3. The solid catalyst component according to claim 1, wherein n in formula (I) is an integer of 1 to 10.

4. The solid catalyst component according to claim 1, wherein n in formula (I) is 1.

5. The solid catalyst component according to claim 1, wherein R in formula (I) is an optionally substituted hydrocarbyl group having .1 to 10 carbon atoms.

6. The solid catalyst component according to claim 1, wherein R in formula (I) is an optionally substituted alkyl group having 1 to 10 carbon atoms.

7. The solid catalyst component according to claim 1, wherein Z in formula (I) is an optionally substituted hydrocarbylene group having 1 to .10 carbon atoms.

8. The solid catalyst component according to claim 1, wherein Z in formula (I) is an optionally substituted alkylene group having 1 to 10 carbon atoms or an arylene group .

9. The solid catalyst component according to claim 1, wherein Z in formula (I) is an optionally substituted alkylene group having 1 to 6 carbon atoms.

10. A process for producing a solid catalyst component for olefin polymerization comprising a titanium atom, a magnesium atom, a halogen atom and an internal electron donor represented by formula (I) , the process comprising a step of bringing a titanium compound, a magnesium compound and the internal electron donor into contact with each other:

^R^%-^Z^)x-^R

( I ) wherein each R is independently an optionally substituted hydrocarbyl group having 1 to 20 carbon atoms, or the two R groups are linked together to form a ring; each X is independently an oxygen atom or a sulfur atom; Z is an optionally substituted hydrocarbylene group having 1 to 20 carbon atoms; and n is an integer of 1 to 100.

11. The process according to claim 10, wherein the magnesium compound is a magnesium halide.

12. The process according to claim 10, wherein the magnesium compound is a dialkoxymagnesium.

13. The process according to claim 10, wherein the step comprises sub-steps of:

(1) bringing the titanium compound into contact with the magnesium compound, thereby producing a solid component comprising a titanium atom and a magnesium atom; and (2) bringing the solid component into contact with the internal electron donor.

14. The process according to claim 13, wherein the solid component is a solid catalyst component precursor for olefin polymerization comprising a trivalent titanium atom, a magnesium atom and a hydrocarbyloxy group.

15. The process according to claim 14, wherein the solid catalyst component precursor is a component produced by a process comprising a step of reducing a titanium compound represented by the following formula (vii) with an organomagnesium compound in the presence of a silicon compound containing a Si-0 bond:

(vii) wherein R⁹ is a hydrocarbyl group having 1 to 20 carbon atoms; each X³ is independently a halogen atom or a hydrocarbyloxy group having 1 to 20 carbon atoms; and m is an integer of 1 to 20.

16. A process for producing a solid catalyst for olefin polymerization, the process comprising a step of bringing the solid catalyst component of claim 1 or a solid catalyst

.

component produced by _^the process of claim 10, an organoaluminum compound and, optionally, an external electron donor into contact with each other.

17. A process for producing an olefin polymer, the process comprising a step, of polymerizing an olefin in the presence of a solid catalyst produced by the process of claim 16.

18. The process according to claim 17, wherein the olefin comprises ethylene and an a-olefin.