JPH1135621A - Production of olefin polymer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for the production of the subject polymer, suppressing controlled deterioration in catalytic functions, e.g. polymerization activity and stereoregularity while it is stored, and capable of being stored for a certain period by polymerizing olefin compound(s) in the presence of a prepolymerization catalyst and polymerization catalyst, the former containing, e.g. solid titanium catalyst component and being treated with alcohol. SOLUTION: This polymer is obtained by polymerization or copolymerization of olefin compound(s) in the presence of a prepolymerization catalyst and olefin polymerization catalyst composed of an organoaluminum compound, wherein the prepolymerization catalyst is obtained by prepolymerization of olefin compound(s) in the presence of (A) a solid titanium catalyst component containing titanium, magnesium and an electron donor, preferably at 50 to 400 g/L, and (B) a catalyst component composed of an organoaluminum compound (e.g. trimethyl aluminum). The prepolymerization catalyst is treated with 0.01 to 10 mols of a tertiary alcohol per mol of the component B, and is preferably incorporated with an organosilicon compound.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a method for producing an olefin polymer. More specifically, the present invention relates to a method for producing an olefin polymer using a prepolymerization catalyst.

[0002]

2. Description of the Related Art An olefin polymer, particularly polypropylene, is a crystalline polymer and therefore has rigidity, heat resistance, chemical resistance,
It is excellent in optical properties, workability, etc., and has a light specific gravity, so that it is widely used in the fields of various injection molded products, containers, packaging materials and the like. Generally, an olefin polymer is polymerized by a Ziegler-Natta catalyst composed of a titanium compound and an organoaluminum compound, which improves the catalytic activity, improves the stereoregularity of the obtained olefin polymer, and forms a polymer powder for stable production. Improvements are being made.

For example, in order to improve polymerization activity and stereoregularity in addition to improving the polymer powder form, a method is known in which the catalyst is previously contacted with a small amount of olefin and treated (preliminary polymerization) and then subjected to polymerization. ing. In this prepolymerization method, since the prepolymerization catalyst is in an activated state, the catalyst performance such as polymerization activity and stereoregularity is not stable even if a washing treatment is performed with a polymerization inert solvent such as hexane. Therefore, the catalyst performance is inevitably reduced during storage. Further, when the prepolymerization catalyst is temporarily stored in a medium containing an olefin or supplied to a polymerization system using the medium, the prepolymerization catalyst is supplied by generation of a polymer in a vessel wall of a storage container or in a supply pipe. There were also problems such as blockage of the piping for use and deterioration of the polymer powder form due to agglomeration of the catalyst.

For this reason, Japanese Patent Application Laid-Open No. Hei 2-202903 discloses a technique of adding titanium tetrachloride after prepolymerization. The technique is effective when the solid catalyst component has a low concentration, but is effective when the solid catalyst component has a high concentration. However, there are problems such as that the obtained polymer is likely to aggregate and the form of the polymer powder is deteriorated.
Japanese Patent Application Laid-Open No. 3-106908 discloses a technique of adding carbon monoxide or carbon dioxide, but the storage stability is insufficient, and further improvement is desired.

[0005]

SUMMARY OF THE INVENTION Under such circumstances, the present invention suppresses a decrease in catalytic performance such as polymerization activity and stereoregularity during storage of a prepolymerized catalyst, and temporarily stores the prepolymerized catalyst with an olefin. It is an object of the present invention to provide a method for producing an olefin polymer which can be smoothly supplied to a polymer or a polymerization system.

[0006]

Means for Solving the Problems The present inventor has conducted intensive studies to achieve the above object. As a result, by treating the prepolymerized catalyst with a tertiary alcohol, the activity was not reduced during the treatment. The present inventors have found that the catalytic performance of the prepolymerized catalyst does not decrease during storage, and that the clogging of the piping when the prepolymerized catalyst is supplied to the polymerization system using a medium containing olefin can also be eliminated, and the present invention has been completed. Was.

That is, the present invention provides the following method for producing an olefin polymer. (1) A prepolymerized catalyst obtained by prepolymerizing an olefin using a catalyst component formed from (A) a solid titanium catalyst component containing titanium, magnesium and an electron donor and (B) an organoaluminum compound is used. A method for producing an olefin polymer, comprising polymerizing or copolymerizing an olefin in the presence of an olefin polymerization catalyst formed from (D) a tertiary alcohol and (E) an organoaluminum compound. (2) The olefin polymer according to (1), wherein the tertiary alcohol is brought into contact with the organoaluminum compound (B) used in the preliminary polymerization in a molar ratio of 0.01 to 10 times (D). Production method. (3) The method for producing an olefin polymer according to the above (1) or (2), wherein the concentration of the solid titanium catalyst component (A) at the time of the prepolymerization is in the range of 50 to 400 g / liter. (4) Addition of (C) an organosilicon compound to a catalyst component formed from (A) a solid titanium catalyst component containing titanium, magnesium and an electron donor and (B) an organoaluminum compound. The method for producing an olefin polymer according to any one of (3). (5) The method for producing an olefin polymer according to any one of the above (1) to (4), wherein (F) an organosilicon compound is added to the olefin polymerization catalyst. (6) The method for producing an olefin polymer according to any one of (1) to (5), wherein the preliminary polymerization catalyst is treated with carbon dioxide before, simultaneously with, or after (D) contacting and reacting the tertiary alcohol.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The process for producing an olefin polymer according to the present invention comprises (A) a solid titanium catalyst component, (B) an organoaluminum compound and, if necessary, (C) an organosilicon compound. (D) a tertiary alcohol contacted with a prepolymerized catalyst obtained by prepolymerizing an olefin using a catalyst component, and (E) an organoaluminum compound,
And, if necessary, the polymerization or copolymerization of olefins in the presence of an olefin polymerization catalyst formed from (F) an organosilicon compound.

(D) The method for producing an olefin polymer according to the above, wherein the carbon dioxide treatment is carried out before, simultaneously with or after contact with the tertiary alcohol. Hereinafter, each catalyst component, adjustment method, polymerization method, and the like will be described. [I] Each catalyst component (A) Solid titanium catalyst component The solid titanium catalyst component contains titanium, magnesium, and an electron donor, and includes the following (a) a titanium compound, (b) a magnesium compound, (c) It is formed from an electron donor and, if necessary, a halide. (a) Titanium compound As the titanium compound, a titanium compound represented by the general formula (I) TiX ¹ _p (OR ¹ ) _4-p (I) can be used.

In the above formula (I), X ¹ represents a halogen atom, preferably a chlorine atom. R ¹ has 1 to ¹ carbon atoms
It represents 10 hydrocarbon groups, particularly preferably a straight-chain or branched-chain alkyl group. When a plurality of R ¹ are present, they may be the same or different. p shows the integer of 0-4. Specific examples of the titanium compound represented by the general formula (I) include tetramethoxytitanium, tetraethoxytitanium, tetra-n-propoxytitanium, tetraisopropoxytitanium, tetra-n-butoxytitanium, tetraisobutoxytitanium, Tetracyclohexyloxytitanium,
Tetraalkoxy titanium such as tetraphenoxy titanium,
Trihalogens such as titanium tetrachloride, titanium tetrachloride, titanium tetrabromide, and titanium tetraiodide, methoxy titanium trichloride, ethoxy titanium trichloride, propoxy titanium trichloride, n-butoxy titanium trichloride, ethoxy titanium tribromide and the like Alkoxytitanium chloride,
Dimethoxytitanium dichloride, diethoxytitanium dichloride, diisopropoxytitanium dichloride, di-n-propoxytitanium dichloride, diethoxytitanium dibromide, etc., dihalogenated dialkoxytitanium, trimethoxytitanium chloride, triethoxytitanium chloride, triisopropoxytitanium Monohalogenated trialkoxy titanium such as chloride, tri-n-propoxytitanium chloride and tri-n-butoxytitanium chloride. Among these, a titanium compound having a high halogen content, particularly titanium tetrachloride, is preferred. These titanium compounds may be used alone or in combination of two or more. (b) Magnesium compound As the magnesium compound, a magnesium compound represented by the general formula (II) MgR ² R ³ ... (II) can be used.

In the above general formula (II), R ² and R ³
Represents a hydrocarbon group, an OR ⁴ group (R ⁴ is a hydrocarbon group), or a halogen atom. More specifically, as a hydrocarbon group, an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group, an aryl group, an aralkyl group, or the like; as an OR ⁴ group, R ⁴ is an alkyl group having 1 to 12 carbon atoms; Examples of a cycloalkyl group, an aryl group, an aralkyl group and the like, and examples of the halogen atom include chlorine, bromine, iodine and fluorine. R ² and R ³ may be the same or different.

Specific examples of the magnesium compound represented by the above general formula (II) include dimethyl magnesium, diethyl magnesium, diisopropyl magnesium, dibutyl magnesium, dihexyl magnesium, dioctyl magnesium, ethyl butyl magnesium, diphenyl magnesium, dicyclohexyl magnesium, dimethoxy magnesium Magnesium, diethoxymagnesium, dipropoxymagnesium, dibutoxymagnesium, dihexyloxymagnesium, dioctoxymagnesium, diphenoxymagnesium, dicyclohexyloxymagnesium, ethylmagnesium chloride, butylmagnesium chloride, hexylmagnesiumchloride, isopropylmagnesiumchloride, isobutyl Magnesium chloride, t-butyl Magnesium chloride, phenylmagnesium bromide, benzylmagnesium chloride, ethylmagnesium bromide, butylmagnesium bromide, phenylmagnesium chloride, butylmagnesium iodide, butoxymagnesium chloride,
Examples thereof include cyclohexyloxy magnesium chloride, phenoxy magnesium chloride, ethoxy magnesium bromide, butoxy magnesium bromide, ethoxy magnesium iodide, magnesium chloride, magnesium bromide, and magnesium iodide. The above magnesium compound can be prepared from metallic magnesium or a compound containing magnesium.

As an example, halogen is added to metallic magnesium.
And general formula X^Two _mM (OR^Five) _nmAl represented by
Coxy group-containing compound (wherein, X^TwoIs hydrogen atom, halogen
Represents an atom or a hydrocarbon group having 1 to 20 carbon atoms;
Represents an iodine, carbon, aluminum, silicon or phosphorus atom
And R^FiveRepresents a hydrocarbon group having 1 to 20 carbon atoms.
n shows the valence of M and n> m ≧ 0. ) Contact
Law.

The above-mentioned halides include silicon tetrachloride, silicon tetrabromide, tin tetrachloride, tin tetrabromide, hydrogen chloride and the like. Among these, silicon tetrachloride is preferred. Examples of the hydrocarbon group of X ² and R ⁵ include an alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a hexyl group, an octyl group, a cyclohexyl group, an allyl group, and a propenyl group. And alkenyl groups such as butenyl group, aryl groups such as phenyl group, tolyl group and xylyl group, and aralkyl groups such as phenethyl and 3-phenylpropyl groups. Among them, an alkyl group having 1 to 10 carbon atoms is particularly preferable. As another example, a method in which a halide is brought into contact with a magnesium alkoxy compound represented by Mg (OR ⁶ ) ₂ (in the formula, R ⁶ represents a hydrocarbon group having 1 to 20 carbon atoms).

The above-mentioned halide is the same as described above. As the above R ⁶ , a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group,
Alkyl groups such as hexyl group and octyl group, alkenyl groups such as cyclohexyl group, allyl group, propenyl group and butenyl group; aryl groups such as phenyl group, tolyl group and xylyl group; aralkyl groups such as phenethyl and 3-phenylpropyl group. And the like. Among these, especially those having 1 to 1 carbon atoms
Ten alkyl groups are preferred.

The above magnesium compounds may be used alone or in combination of two or more. (c) Electron Donor Examples of the electron donor include alcohols, phenols, ketones, aldehydes, carboxylic acids, malonic acids, esters of organic acids or inorganic acids, ethers such as monoether, diether or polyether. And nitrogen-containing electron donors such as ammonia, amines, nitriles and isocyanates. Among these, esters of polycarboxylic acids are preferred,
More preferred are esters of aromatic polycarboxylic acids. Particularly, esters of aromatic dicarboxylic acids are preferred. Further, an aliphatic hydrocarbon in which the organic group in the ester portion is linear, branched or cyclic is preferable.

Specifically, phthalic acid, naphthalene-1,
2-dicarboxylic acid, naphthalene-2,3-dicarboxylic acid, 5,6,7,8-tetrahydronaphthalene-1,2
Methyl, ethyl, n- of dicarboxylic acids such as dicarboxylic acid, 5,6,7,8-tetrahydronaphthalene-2,3-dicarboxylic acid, indane-4,5-dicarboxylic acid and indane-5,6-dicarboxylic acid; Propyl, isopropyl, n-butyl, isobutyl, t-butyl, n-pentyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 1,1-dimethylpropyl, 1-methylpentyl, 2-methylpentyl, 3-methyl Pentyl, 4-methylpentyl, 1-ethylbutyl, 2-ethylbutyl,
n-hexyl, cyclohexyl, n-heptyl, n-octyl, n-nonyl, 2-methylhexyl, 3-methylhexyl, 4-methylhexyl, 2-ethylhexyl,
3-ethylhexyl, 4-ethylhexyl, 2-methylpentyl, 3-methylpentyl, 2-ethylpentyl,
Examples thereof include dialkyl esters such as 3-ethylpentyl. Among these, phthalic acid diesters are preferable, and a linear or branched aliphatic hydrocarbon having 4 or more carbon atoms in the organic group in the ester portion is preferable.

As specific examples, di-n-butyl phthalate, diisobutyl phthalate, di-n-heptyl phthalate, diethyl phthalate and the like can be preferably mentioned. These aromatic carboxylic acid diester compounds may be used alone or in combination of two or more. (B) Organoaluminum Compound As the (B) organoaluminum compound used in the prepolymerization of the present invention, those having an alkyl group, a halogen atom, a hydrogen atom, an alkoxy group, aluminoxanes, and mixtures thereof can be used. Specifically, trialkylaluminum such as trimethylaluminum, triethylaluminum, triisopropylaluminum, triisobutylaluminum, trioctylaluminum, diethylalkylmonochloride, diisopropylaluminum monochloride, diisobutylaluminum monochloride, dialkyl such as dioctylaluminum monochloride Examples thereof include alkylaluminum sesquihalides such as aluminum monochloride and ethylaluminum sesquichloride, and chain aluminoxanes such as methylaluminoxane. Among these organoaluminum compounds, trialkylaluminum having a lower alkyl group having 1 to 5 carbon atoms, particularly trimethylaluminum, triethylaluminum, tripropylaluminum and triisobutylaluminum are preferable. These organoaluminum compounds may be used alone or in combination of two or more. (C) Organosilicon compound In the prepolymerization of the present invention, it is preferable to add (C) an organosilicon compound as necessary. As the organosilicon compound (C), an organosilicon compound having a Si—O—C bond can be preferably exemplified.

A typical example of this is represented by the general formula R ⁷ _S Si
A silicate represented by (OR ⁸ ) _4-S can be mentioned. In the formula, R ⁷ represents a hydrocarbon group or a halogen atom, wherein the hydrocarbon group is an alkyl group, a cycloalkyl group, an aryl group, an alkenyl group, a haloalkyl group, an aminoalkyl group, or the like; and the halogen atom is a chlorine atom or the like. Is mentioned. R ⁸ represents a hydrocarbon group, and includes an alkyl group, a cycloalkyl group, an aryl group, an alkenyl group,
And an alkoxyalkyl group. s is 0 or 1
Indicates an integer of 3. When there are a plurality of R ⁷ or R ⁸ , they may be the same or different. In addition, siloxanes, silyl esters of carboxylic acids, and the like can be given.

Specific examples of the above include trimethylmethoxysilane, trimethylethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, diphenyldimethoxysilane, methylphenyldimethoxysilane, diphenyldiethoxysilane, dicyclohexyldimethoxysilane, cyclohexylmethyldimethoxysilane, Cyclohexyl-1,1,2-trimethylpropyldimethoxysilane, α-naphthyl-1,1,2-trimethylpropyldimethoxysilane, n-tetradecanyl-1,
1,2-trimethylpropyldimethoxysilane, cyclopentylmethyldimethoxysilane, cyclopentylethyldimethoxysilane, cyclopentylpropyldimethoxysilane, cyclopentyl-t-butyldimethoxysilane, cyclopentyl-1,1,2-trimethylpropyldimethoxysilane, dicyclopentyldimethoxysilane, Cyclopentylcyclohexyldimethoxysilane,
t-butylmethyldimethoxysilane, t-butylethyldimethoxysilane, t-butylpropyldimethoxysilane, di-t-butyldimethoxysilane, diisopropyldimethoxysilane, isopropylisobutyldimethoxysilane, γ-chloropropyltrimethoxysilane, methyltriethoxysilane , Ethyltriethoxysilane, vinyltriethoxysilane, butyltriethoxysilane,
Phenyltriethoxysilane, γ-aminopropyltriethoxysilane, chlorotriethoxysilane, ethyltriisopropoxysilane, vinyltributoxysilane,
Methyl-t-butoxymethoxysilane, isopropyl-
t-butoxymethoxysilane, cyclopentyl-t-butoxymethoxysilane, 1,1,2-trimethylpropyltrimethoxysilane, ethyl silicate, butyl silicate,
Trimethylphenoxysilane, methyltriaryloxysilane, vinyltris (β-methoxyethoxy) silane,
Vinyl trisacetoxysilane, dimethyltetraethoxydisiloxane and the like can be mentioned. These organic silicon compounds may be used alone or in combination of two or more. Further, as the (C) organosilicon compound, a silicon compound having no Si—O—C bond and an organic compound having an O—C bond are preliminarily reacted or α.
-An organic silicon compound having a Si-O-C bond that is reacted during the polymerization of an olefin. Specific examples include those in which silicon tetrachloride is reacted with an alcohol. (D) Tertiary alcohol In the method for producing an olefin polymer of the present invention, after preliminarily polymerizing an olefin using the above-mentioned catalyst component,
The main feature of the present invention is that (D) a tertiary alcohol is brought into contact to form a prepolymerization catalyst, and the (D) tertiary alcohol is represented by a general formula R ⁹ R ¹⁰ R ¹¹ COH. Where:
R ⁹ , R ¹⁰ , and R ¹¹ each represent a hydrocarbon group having 1 to 10 carbon atoms, and examples of the hydrocarbon group include an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, an alkenyl group, an alkoxyalkyl group, and a haloalkyl group. However, a chain or cyclic saturated aliphatic or aromatic hydrocarbon group is preferable, and a chain saturated hydrocarbon is more preferable. R ⁹ ,
R ¹⁰ and R ¹¹ may be the same or different.

Specific examples of the above include t-butanol,
t-pentanol, 2-methyl-3-pentanol, triethylcarbinol, 2,3-dimethyl-2-butanol, 2-methyl-2-hexanol, 2-methyl-2
-Heptanol, 2-methyl-2-octanol, triphenylcarbinol, 2-phenyl-2-hexanol, 1,1-diphenylethanol, 1-phenyl-2
-Methyl-2-propanol, tricyclohexylcarbinol, 1-adamantanol, 2-methyl-2-adamantanol and the like. Among these tertiary alcohols, tertiary alcohols having 4 to 8 carbon atoms, particularly t-butanol, are preferred. These tertiary alcohols may be used alone or in combination of two or more. (E) Organoaluminum Compound The (E) organoaluminum compound used in the method for producing an olefin polymer of the present invention includes the above (B)
What is necessary is just to select from organic aluminum compounds. Further, the same or different (A) organoaluminum compound may be used. (F) Organosilicon compound The olefin polymerization catalyst of the present invention may optionally contain
(F) It is preferable to add an organosilicon compound. This (F) organosilicon compound may be selected from the above (C) organosilicon compounds. Further, the same or different (C) organosilicon compound can be used. [II] Adjustment of solid titanium catalyst component The solid titanium catalyst component is adjusted by the above-mentioned (a) titanium compound, (b) magnesium compound, (c) electron donor, and, if necessary, (d) halide. May be contacted and reacted in a usual manner, but it is preferable to contact and react in the following amounts, conditions and procedures.

The amount of the titanium compound to be used is generally 0.5 to 100 mol, preferably 1 to 50 mol, per 1 mol of magnesium of the magnesium compound. The amount of the electron donor to be used is usually 0.01 to 10 mol, preferably 0.1 to 10 mol, per 1 mol of magnesium of the magnesium compound.
It is good to make it the range of 05-0.15 mol. Further, silicon tetrachloride may be added as a halide.

The contact / reaction temperature is usually -20 to 2
The temperature is preferably in the range of 00 ° C, preferably 20 to 150 ° C, and the contact / reaction time is usually in the range of 1 minute to 24 hours, preferably 10 minutes to 6 hours. This contact procedure is not particularly limited. For example, each component may be contacted and reacted in the presence of an inert solvent such as a hydrocarbon, or each component may be diluted and contacted and reacted with an inert solvent such as a hydrocarbon in advance. Examples of the inert solvent include n-pentane, isopentane, n-hexane, and n-pentane.
-Aliphatic hydrocarbons such as heptane, n-octane and isooctane; aromatic hydrocarbons such as benzene, toluene and xylene; and mixtures thereof.

It is preferable that the contact and reaction of the titanium compound be performed twice or more to sufficiently support the magnesium compound serving as a catalyst carrier. The solid catalyst component obtained by the above contact and reaction may be washed with an inert solvent such as a hydrocarbon. This inert solvent may be the same as described above. The solid product can also be stored dry or in an inert solvent such as a hydrocarbon. [III] Pre-polymerization The pre-polymerization is carried out according to the above (A) solid titanium catalyst component,
(B) using a catalyst component formed from an organoaluminum compound and, if necessary, (C) an organosilicon compound, usually polymerizing a small amount of an olefin;
It is preferable to use the following amounts, conditions, and procedures.

The amount of the organoaluminum compound (B) to be used is usually 0.01 to 100 mol, preferably 0.1 to 100 mol, per 1 mol of titanium in the solid titanium catalyst component (A). It is good to make it into the range of 50 mol. The amount of the organosilicon compound (C) to be used is usually 0.1 to 1 mol of titanium in the solid titanium catalyst component.
It is good to make it into the range of 01-100 mol, preferably 0.1-50 mol.

The order of contact of the above components is not particularly limited, but preferably, (A) the solid titanium catalyst component is brought into contact with (B) an organoaluminum compound, and then (C)
Contacting an organosilicon compound, and
(B) An organoaluminum compound is brought into contact with (C) an organosilicon compound and then (A) with a solid titanium catalyst component.

After contacting each component, the solid component may be washed with an inert solvent such as a hydrocarbon. As the olefin used for the prepolymerization, ethylene, propylene, 1-
Butene, 1-pentene, 1-hexene, 4-methyl-1
-Pentene, etc., and these may be used alone or in combination of two or more. If desired, a chain transfer agent may be added, and hydrogen is preferably used. Usually 2
The added amount is 0 mol% or less.

The prepolymerization is preferably carried out in an inert organic solvent, which includes n-pentane,
Aliphatic hydrocarbons such as isopentane, n-hexane, n-heptane, n-octane, isooctane, benzene,
Examples thereof include aromatic hydrocarbons such as toluene and xylene, and mixtures thereof. Among these, n-heptane is particularly preferred.

When the prepolymerization is carried out in an inert organic solvent, the concentration of the solid titanium catalyst component (A) is adjusted to 50 to 50%.
It is preferably in the range of 400 g / liter,
More preferably, it is in the range of 200 g / liter.
If the amount is less than 50 g / liter, the amount of the pre-polymerization treatment that can be performed becomes small, and it is not preferable to increase the size of the pre-polymerization unit in order to carry out the predetermined amount of the pre-polymerization treatment within a predetermined time. On the other hand, if it exceeds 400 g / liter, it is necessary to remarkably increase the olefin partial pressure in order to obtain a predetermined prepolymer, the uniformity deteriorates, and the supply of the prepolymer to the next step deteriorates. Inconveniences such as are likely to occur. The pre-polymerization pressure is not particularly limited, and is usually from atmospheric pressure to 2
The range may be 0 kg / cm ² G.

The prepolymerization temperature is usually from -20 to 110.
° C, preferably in the range of 0 to 60 ° C, and the prepolymerization time is usually 1 minute to 24 hours, preferably 15 minutes.
The time should be in the range of minutes to 7 hours. The prepolymerization amount is (A)
Usually, 0.00 g per 1 g of the solid titanium catalyst component.
The amount should be in the range of 1 to 1000 g, preferably 0.01 to 100 g. This prepolymerization can be carried out batchwise,
It may be a continuous type. The prepolymerized catalyst obtained by prepolymerizing the above olefin may be washed with an inert solvent such as a hydrocarbon. The washing may be performed according to a conventional method using an inert solvent. Examples of the inert solvent include n-pentane, isopentane, n-hexane, n-heptane, and n-pentane.
Examples thereof include aliphatic hydrocarbons such as octane and isooctane, aromatic hydrocarbons such as benzene, toluene and xylene, and mixtures thereof. [IV] Contact of Tertiary Alcohol after Prepolymerization The present invention is mainly characterized in that a prepolymerized catalyst obtained by prepolymerizing an olefin as described above is brought into contact with (D) a tertiary alcohol. is there. The contact amount of the (D) tertiary alcohol is usually 0.01 to 10 mol, preferably 0.1 to 1 mol per 1 mol of aluminum of the organoaluminum compound used in the preliminary polymerization.
It is preferred to be in the range of 3 mol. If the amount is less than 0.01 mol, it becomes difficult to suppress a decrease in catalyst activity during storage, and it is also difficult to obtain an effect of improving catalyst preservability in olefin or catalyst supply using olefin as a medium.
On the other hand, if it exceeds 10 moles, the contact effect of the tertiary alcohol does not increase, and conversely the catalyst may be deactivated, which is not preferable. The contact temperature is usually in the range of −20 to 110 ° C., preferably 0 to 60 ° C.

The contact time is usually in the range of 1 minute to 24 hours, preferably 5 minutes to 1 hour. The contact is preferably performed in an inert organic solvent. Examples of the inert organic solvent include aliphatic hydrocarbons such as n-pentane, isopentane, n-hexane, n-heptane, n-octane and isooctane, benzene, and toluene. And aromatic hydrocarbons such as xylene, and mixtures thereof. Among these, n-heptane is particularly preferred. This contact may be a batch type or a continuous type. [V] Contact with carbon dioxide (D) It is preferred to contact carbon dioxide before, simultaneously with or after contact with the tertiary alcohol. When the contact of carbon dioxide is used in combination with the contact of tertiary alcohol, contact is made (D)
In some cases, the desired effect can be obtained even when the amount of the tertiary alcohol added is about one half. The contact amount of carbon dioxide is usually 0.01 to 1 mol of aluminum of the organoaluminum compound (B) used at the time of prepolymerization.
-100 mol, preferably 0.1-50 mol. If the amount is less than 0.01 mol, it becomes difficult to suppress a decrease in catalyst activity during storage, and it is difficult to obtain an effect of improving catalyst supply properties. On the other hand, even if it exceeds 100 mol, the contact effect of carbon dioxide does not increase. The contact temperature is usually -20 to 110C, preferably 0 to 6C.
The temperature is preferably in the range of 0 ° C.

The contact time is usually from 1 minute to 10 days,
Preferably, it is good to be in the range of 1 hour to 4 days. The contact is preferably performed in an inert organic solvent. Examples of the inert organic solvent include aliphatic hydrocarbons such as n-pentane, isopentane, n-hexane, n-heptane, n-octane and isooctane, benzene, and toluene. And aromatic hydrocarbons such as xylene, and mixtures thereof. Among these, n-heptane is particularly preferred. This contact may be a batch type or a continuous type. [VI] Polymerization The process for producing an olefin polymer of the present invention comprises, as a main catalyst, a catalyst obtained by bringing the above prepolymerized catalyst into contact with a tertiary alcohol, (E) an organic aluminum compound, and if necessary, (F) an organic compound. It is characterized in that olefin is polymerized in the presence of an olefin polymerization catalyst comprising a silicon compound, and the polymerization method and its conditions are not particularly limited, and include solution polymerization, slurry polymerization, gas phase polymerization, and bulk polymerization. Although it can be applied to any of polymerization and the like, it can be preferably used for gas phase polymerization.

The olefins usable in the polymerization include ethylene, propylene, 1-butene, 1-octene, 1-octene.
Decene, 3-methyl-1-pentene, 4-methyl-1-
Α-olefins such as pentene can be mentioned. It can be preferably applied to α-olefins having 3 or more carbon atoms, and is particularly suitable for the polymerization of propylene. Further, it can be preferably applied to copolymerization of propylene with ethylene, 1-butene or 1-hexene.

The molecular weight can be adjusted by adding a chain transfer agent, preferably by adding hydrogen. Also,
An inert gas such as nitrogen may be present. For example, in the case of gas phase polymerization, the polymerization pressure is not particularly limited, and is usually from atmospheric pressure to 80 kg / cm ² G, preferably from ^{2 to} 50 kg / c.
It is good to be in the range of m ² G.

The polymerization temperature is usually in the range of 20 to 90 ° C., preferably 40 to 90 ° C.
Usually, it is good to be in the range of 5 minutes to 20 hours, preferably 10 minutes to 10 hours. The amount of the prepolymerized catalyst used under the polymerization conditions is usually 0.0001 to 10 mmol / kg-powder, preferably 0.001 to 1 mmol / kg-powder, as titanium atoms of the solid titanium catalyst component. It is good to be within the range.

The amount of the organoaluminum compound (E) to be used is generally 1 to 10000 mol, preferably 10 to 1 mol, per 1 mol of titanium in the above prepolymerized catalyst.
It may be in the range of 000 mol. The amount of the organosilicon compound (F) to be used is generally 0.1 to 5000 mol, preferably 1 to 1000 mol, per 1 mol of titanium in the above prepolymerized catalyst component. Good. The order of contact of the above components is not particularly limited, but preferably, the prepolymerized catalyst is brought into contact with the (E) organosilicon compound after the (E) organoaluminum compound is brought into contact with the prepolymerized catalyst. ) An organoaluminum compound is brought into contact with a prepolymerization catalyst after contacting (F) an organosilicon compound. Further, in the case of solution polymerization and slurry polymerization, examples of the solvent that can be used for the polymerization include n-pentane, isopentane, n-hexane, and n-hexane.
-Heptane, n-octane, aliphatic hydrocarbons such as isooctane, benzene, toluene, aromatic hydrocarbons such as xylene or a mixture thereof,
Of these, n-heptane is preferred.

The polymerization pressure at this time is usually from normal pressure to 200 k
g / cm ² , preferably in the range of ^{2 to} 150 kg / cm ² , the polymerization temperature is usually 10 to 200 ° C., preferably 40 to 100 ° C., and the polymerization time is generally 5 minutes to 20 minutes.
Time, preferably 10 minutes to 10 hours. The amount of the prepolymerized catalyst used is usually in the range of 0.001 to 0.1 mmol / L, preferably 0.005 to 0.05 mmol / L, as titanium atoms of the solid titanium catalyst component. The amount of the organoaluminum compound (E) to be used is generally 1 to 10000 mol, preferably 1 to 1 mol, per 1 mol of titanium in the prepolymerization catalyst.
It is good to be in the range of 0 to 1000 mol. The amount of the organosilicon compound (F) is usually 0.1 to 50 mol per 1 mol of titanium in the prepolymerization catalyst.
It is good to be 00 mol, preferably in the range of 1 to 1000 mol. These may be charged into a polymerization vessel by a usual method, and the contact procedure and the like are not particularly limited. Furthermore, the present invention is applicable to both batch polymerization and continuous polymerization, and is also applicable to two-stage polymerization and multi-stage polymerization under different conditions.

[0038]

[Example 1]

(1) Preparation of Solid Titanium Catalyst Component After replacing a three-necked flask with a stirrer having an inner volume of 5 liters with nitrogen gas, 500 ml of dehydrated heptane was added.
1, 160 g (1.4 mol) of diethoxymagnesium were added. Heat to 40 ° C., 28.5 ml of silicon tetrachloride
(225 mmol) and the mixture was stirred for 20 minutes, and 25.2 ml (127 mmol) of diethyl phthalate was added.
The solution was heated to 80 ° C., and 461 ml (4.2 mol) of titanium tetrachloride was added dropwise using a dropping funnel, and the mixture was stirred at an internal temperature of 110 ° C. for 2 hours to carry out a loading operation. Then, it was sufficiently washed with dehydrated heptane. Further, 768 ml (7 mol) of titanium tetrachloride was added, and the internal temperature was 110 ° C.
Then, the mixture was stirred for 2 hours to perform a second loading operation. Thereafter, the solid was thoroughly washed with dehydrated heptane to obtain a solid titanium catalyst component (titanium carrying amount = 3.0% by weight). (2) Preliminary polymerization In a three-necked flask equipped with a stirrer having an internal volume of 1 liter and purged with nitrogen, 60 g of the solid titanium catalyst component (37.
Heptane slurry containing 6 mmol-Ti)
Further, dehydrated heptane is added, and the total amount is 500 m.
l. The mixture was stirred while being controlled at 10 ° C., and 24.8 mmol of triethylaluminum and 12.4 mmol of cyclohexylmethyldimethoxysilane were added. 10
At 40 ° C., a predetermined amount of propylene was absorbed for 40 minutes, the residual propylene was replaced with nitrogen, and sufficiently washed with heptane to obtain 65 g of a prepolymerized catalyst (sealing amount: 0.2 g).
083 g-PP / g solid titanium catalyst component). (3) Tertiary alcohol treatment of prepolymerized catalyst 230 ml of a heptane slurry containing 30 g (17.3 mmol-Ti) of the above prepolymerized catalyst was charged into a three-necked flask equipped with a stirrer having an internal volume of 1 liter and purged with nitrogen. Then, while stirring at 25 ° C, t-butanol 0.56m
1 (5.7 mmol) was added, and after 5 minutes, stirring was stopped to terminate the treatment. (4) Propylene Slurry Polymerization A stainless steel autoclave with an internal volume of 1 liter and equipped with a stirrer was sufficiently dried, and after replacement with nitrogen, 400 ml of dehydrated heptane at room temperature was added. 2 mmol of triethylaluminum, 0.25 mmol of cyclohexylmethyldimethoxysilane, 8.7 mg (corresponding to 8.0 mg of a solid titanium catalyst component) of the above prepolymerized catalyst treated with t-butanol were added, and hydrogen was added at 1 kg / cm ^2. G, then 80 ° C, total pressure 8k while introducing propylene
g / cm ² G, and then polymerization was carried out for 60 minutes. Thereafter, the temperature was lowered and the pressure was released, and the contents were taken out and poured into 2 liters of methanol to deactivate the catalyst. It is filtered off and vacuum dried to obtain 112 g of propylene polymer.
(Activity: 14.0 kg-PP / g solid titanium catalyst component). The prepolymerized catalyst treated with t-butanol was slurried in heptane (prepolymerization catalyst concentration: 1).
(30 g / liter) at a temperature of 30 ° C. for one week, and then the polymerization was evaluated under the above conditions. As a result, 112 g of a propylene polymer was obtained. (5) Preservation test in olefin monomer In order to simply verify the preservability of the catalyst in propylene, a t-butanol-treated prepolymerized catalyst 0.5 precisely weighed in a nitrogen-substituted pressure-resistant stainless steel tube having an inner volume of 100 ml was used.
g, and then sufficiently vacuum-dried. Then, 50 g of liquid propylene was charged, left at 25 ° C. for 12 hours, depressurized and vacuum-dried, and the weight of the catalyst was measured. Further, when the form of the catalyst was visually observed, there was almost no change. [Comparative Example 1] Catalyst preparation and performance evaluation were performed in the same manner as in [Example 1] except that the t-butanol treatment was not performed. The results are shown in Table 1. Example 2 Example 2 was repeated except that the amount of t-butanol added at the time of t-butanol treatment of the prepolymerized catalyst was 0.20 times the molar amount of the aluminum compound added during the prepolymerization. The same catalyst preparation and performance evaluation as in [1] were performed. The results are shown in Table 1. Example 3 Example 3 was repeated except that the amount of t-butanol added at the time of treating the prepolymerized catalyst with t-butanol was 1.00 times the molar amount of the aluminum compound added during the prepolymerization. The same catalyst preparation and performance evaluation as in [1] were performed. The results are shown in Table 1. [Comparative Example 2] Al of aluminum compound added at the time of preliminary polymerization using ethanol instead of t-butanol
Catalyst preparation and performance evaluation were performed in the same manner as in [Example 1] except that the amount of ethanol added to the prepolymerized catalyst when the ethanol treatment was performed was 0.25 times the molar amount. The results are shown in Table 1. [Comparative Example 3] Al of aluminum compound added at the time of preliminary polymerization using ethanol instead of t-butanol
The same catalyst preparation and performance evaluation as in [Example 1] were carried out except that the amount of ethanol added to the prepolymerized catalyst in the treatment with ethanol was changed to 0.50 times the molar amount. The results are shown in Table 1. [Comparative Example 4] Isopropanol was used in place of t-butanol, and the amount of isopropanol added to the prepolymerized catalyst in the case of isopropanol treatment was 0.25 with respect to the Al amount of the aluminum compound added during the prepolymerization.
Catalyst preparation and performance evaluation were performed in the same manner as in [Example 1], except that the amount was doubled. The results are shown in Table 1. [Comparative Example 5] Isopropanol was used in place of t-butanol, and the molar ratio of isopropanol added to the prepolymerized catalyst in isopropanol treatment was 0.50 with respect to the Al amount of the aluminum compound added during the prepolymerization.
Catalyst preparation and performance evaluation were performed in the same manner as in [Example 1], except that the amount was doubled. The results are shown in Table 1. [Comparative Example 6] Isopropanol was used in place of t-butanol, and the amount of isopropanol added to the prepolymerized catalyst when treated with isopropanol was 1.00 in molar ratio with respect to the amount of Al in the aluminum compound added during the prepolymerization.
Catalyst preparation and performance evaluation were performed in the same manner as in [Example 1], except that the amount was doubled. The results are shown in Table 1. Example 4 (1) Preparation of Solid Titanium Catalyst Component, Prepolymerization and Washing The same operation as in Example 1 was performed. (2) Carbon Dioxide Treatment of Preliminary Polymerization Catalyst A stainless steel autoclave with a stirrer having an inner volume of 1 liter was sufficiently dried, and after replacing with nitrogen, 40 ml of the prepolymerization catalyst was added.
g of a heptane slurry containing 0.3 g of carbon dioxide gas, and stirring at 25 ° C. with 0.3 kg / cm ² G of carbon dioxide gas.
, And contacted for 24 hours, followed by purging with nitrogen to complete the treatment. (3) Treatment of prepolymerized catalyst with t-butanol The above carbon dioxide-treated prepolymerized catalyst 3 was placed in a three-necked flask equipped with a stirrer having an internal volume of 1 liter and purged with nitrogen.
230 g of a heptane slurry containing 0 g (17.3 mmol-Ti) was added, and 0.28 ml (2.9 mmol) of t-butanol was added while stirring at 25 ° C.
After a lapse of minutes, the stirring was stopped and the process was terminated. (4) Propylene Slurry Polymerization A stainless steel autoclave with an internal volume of 1 liter and equipped with a stirrer was sufficiently dried, and after replacement with nitrogen, 400 ml of dehydrated heptane at room temperature was added. Triethylaluminum 2 mM, cyclohexylmethyldimethoxysilane 0.
8.6 mg of the prepolymerized catalyst treated with 25 mM of the above-mentioned t-butanol was added, hydrogen was introduced at 1 kg / cm ² G, and then propylene was introduced at 80 ° C. and the total pressure was 8 k.
g / cm ² G, and then polymerization was carried out for 60 minutes. Thereafter, the temperature was lowered and the pressure was released, and the contents were taken out and poured into 2 liters of methanol to deactivate the catalyst. It is filtered off and dried under vacuum to obtain 115 g of a propylene polymer.
Obtained. The prepolymerized catalyst treated with t-butanol was slurried in heptane (prepolymerized catalyst concentration: 13%).
(0 g / liter) at a temperature of 30 ° C. for one week, and then the polymerization was evaluated under the above conditions. As a result, 115 g of a propylene polymer was obtained. (5) Storage test in olefin monomer The same test as in [Example 1] showed almost no change in weight. [Comparative Example 7] Catalyst preparation and performance evaluation were performed in the same manner as in [Example 4], except that the t-butanol compound treatment was not performed. The results are shown in Table 1. Example 5 The procedure of Example 5 was repeated except that the amount of t-butanol added to the prepolymerized catalyst in the treatment with t-butanol was 0.10 times the molar amount of the aluminum compound added during the prepolymerization. The same catalyst preparation and performance evaluation as in [4] were performed. The results are shown in Table 1. Example 6 The procedure of Example 6 was repeated except that the amount of t-butanol added in the treatment with t-butanol was 0.50 times the molar amount of the aluminum compound added during the prepolymerization. The same catalyst preparation and performance evaluation as in [4] were performed. The results are shown in Table 1.

[0039]

[Table 1]

[0040]

Industrial Applicability According to the present invention, deterioration of catalytic performance such as polymerization activity and stereoregularity during storage of a prepolymerized catalyst is suppressed, and temporary storage of a prepolymerized catalyst by olefin or smooth supply to a polymerization system is achieved. It is possible to provide a method for producing an olefin polymer which is possible.

[Brief description of the drawings]

FIG. 1 is a flow chart showing one embodiment of the olefin polymerization of the present invention.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takeshi Ota 1-1, Anesaki Beach, Ichihara-shi, Chiba Prefecture (72) Inventor Hideo Funabashi 1-1, Anesaki Beach, Ichihara-shi, Chiba Prefecture

Claims (6)

[Claims] 1. A prepolymer obtained by prepolymerizing an olefin using a catalyst component formed from (A) a solid titanium catalyst component containing titanium, magnesium and an electron donor and (B) an organoaluminum compound. In the presence of an olefin polymerization catalyst formed from a catalyst which has been brought into contact with (D) a tertiary alcohol and (E) an organoaluminum compound,
A method for producing an olefin polymer, comprising polymerizing or copolymerizing an olefin. 2. The olefin polymer according to claim 1, which is brought into contact with (D) a tertiary alcohol in a molar ratio of 0.01 to 10 times with respect to (B) the organoaluminum compound used in the prepolymerization. Production method. 3. The process for producing an olefin polymer according to claim 1, wherein the concentration of the solid titanium catalyst component (A) during the prepolymerization is in the range of 50 to 400 g / l. 4. An organosilicon compound (C) is added to a catalyst component formed from (A) a solid titanium catalyst component containing titanium, magnesium and an electron donor and (B) an organoaluminum compound. The method for producing an olefin polymer according to any one of claims 1 to 3. 5. The process for producing an olefin polymer according to claim 1, wherein (F) an organosilicon compound is added to the olefin polymerization catalyst. 6. The process for producing an olefin polymer according to claim 1, wherein the prepolymerization catalyst is treated with carbon dioxide before, simultaneously with, or after (D) contacting with a tertiary alcohol.