JP6829884B2 - Ziegler-Natta catalyst with cyclobutane dicarboxylic acid esters as electron donors - Google Patents

Description

The present invention relates to a novel non-phthalate electron donor in a Ziegler-Natta catalyst, and a polymerization catalyst using the present invention.

Polyolefins such as polyethylene and polypropylene are general-purpose resins used in a wide variety of industrial products. It is an indispensable material for industrial products. Polyolefins are obtained by polymerizing olefins such as ethylene and propylene in the presence of various catalysts, and Ziegler-Natta catalysts are typical such catalysts.

As described in Non-Patent Document 1, the Ziegler-Natta catalyst currently widely used industrially is the MgCl _2- supported TiCl type ₄ Ziegler-Natta catalyst (hereinafter referred to as "Mg / Ti catalyst") developed in the 1970s. ) Is the basic form. The Mg / Ti catalysts currently used especially for propylene polymerization have achieved high activity and high stereospecificity by using phthalates as electron donors. At present, as an electron donor of a highly active Mg / Ti catalyst, a combination of phthalates as so-called internal donors added at the time of catalyst preparation and alkoxysilanes as so-called external donors added directly into the polymerization system is the most suitable. It has proven to be effective.

Highly active Mg / Ti catalysts using such electron donors are described in many publications such as Patent Document 1, Patent Document 2, and Patent Document 3.

The present inventor himself also uses highly active Mg / using dibutyl phthalate (DBP) as an internal donor and cyclohexylmethyldimethoxysilane (CMDMS) as an external donor, which are industrially used in Non-Patent Document 2. The Ti catalyst and the ethylene / 1-hexane copolymer produced by using the Ti catalyst are considered.

However, in recent years, the safety of plasticizers such as phthalates has been questioned, and the use of various plasticizers tends to be regulated in each country. For example, the European regulation REACH (Registration, Evolution, Autrationation and Restriction of Chemicals) by 2013 is dibutyl phthalate (DBP), diisobutyl phthalate (DIBP), dipentyl phthalate (DPP), n-pentyl phthalate. Isopentyl (PIPP), Dipentyl phthalate (DIPP), 1,2-benzenedicarboxylic acid dipentyl ester (branched, linear), benzylbutyl phthalate (BBP), dihexyl phthalate (DHP), 1,2-benzenedicarboxylic di C _{6 over 8} branched alkyl ester _{(C 7} rich), the use of phthalic acid bis (2-ethylhexyl) (DEHP), 1,2-benzene dicarboxylic acid di C _{7 over 11} branched and straight chain alkyl ester to toys When these phthalates are contained in a molded product, various obligations such as keeping the content within the limit value and notifying the molded product are imposed. Therefore, in order to avoid such regulations and obligations, resin molded products containing no phthalate ester have been required in recent years.

When olefins are polymerized in the presence of a highly active Mg / Ti catalyst, the amount of catalyst remaining in the obtained polyolefin is extremely small, so the catalyst residue is removed from the obtained polyolefin in the current polyolefin manufacturing process. No process is provided. Therefore, the polyolefins produced by using the Mg / Ti catalyst using the phthalates as the electron donor theoretically contain the phthalates. The market value of such polyolefin products is declining because they carry potential risks in the light of national regulations.

Therefore, olefin polymerization catalysts for producing polyolefins containing no phthalates, that is, new Mg / Ti catalysts in which the electron donor is replaced with a compound other than phthalates has been actively developed. There is.

As electron donors other than phthalates that are effective as electron donors for Mg / Ti catalysts (hereinafter, "non-phthalate donors"), malonic acid esters (Patent Document 4) and β-substituted glutarates have been used. (Patent Document 5), substituted maleic acid ester (Patent Document 6), β-keto-ester derivative (Patent Document 7), succinic acid ester (Patent Document 8), polyol ester (Patent Document 9), dibasic ester compound. (Patent Document 10), special cyclic ester compounds (Patent Documents 11 and 12) and the like have been reported. As the use of phthalates is regulated, the development of industrially advantageous non-phthalate donors is expected to become more active in the future.

By the way, Non-Patent Document 3 describes a photodimer of a cinnamic acid derivative as a diester of a biologically-derived aromatic group-containing carboxylic acid effective as a raw material for polyimide. Non-Patent Document 3 describes the following synthetic route of 4,4-diamino-α-torxylate diester as an example of producing a photodimer of the cinnamic acid derivative.

"Polyolefins so far and in the future" 2006 Chugoku-Shikoku Branch of the Society of Polymer Science, Japan 32nd Polymer Course Abstracts "Multilateral characterization for industrial Ziegler-Natta catalysts toward characterization of structure-performance reservation ship" T.K. Taniike, T.M. Funako, M.M. Terrano, Journal of Catalysis 311 (2014) 33-40 "Biobased Polyamides from 4-Aminocinnamic Acid Photodimer" P.I. Subannasara, S.A. Tateyama, A. Miyasato, K.K. Matsumira, T.M. Shimoda, T.K. Ito, Y. Yamagata, T.M. Fujita, N.K. Takaya, T.M. Kaneko, Macromolecules 2014, 47, 1586-1393

Japanese Unexamined Patent Publication No. 10-21893 Japanese Unexamined Patent Publication No. 2001-151816 Japanese Unexamined Patent Publication No. 2000-297104 International Publication No. 98/56830 (WO98 / 56830A2) International Publication No. 00/55215 (WO00 / 55215 A1) International Publication No. 03/022894 (WO03 / 022894 A1) International Publication No. 2005/097841 (WO2005 / 097841 A1) International Publication No. 00/63261 (WO00 / 63261A1) International Publication No. 03/06828A (WO03 / 068828 A1) International Publication No. 2005/108588 (WO2005 / 105858 A1) International Publication No. 2006/077945 (WO2006 / 077946 A1) International Publication No. 2006/077946 (WO 2006/077945 A1)

The applications of cyclobutanedicarboxylic acid esters described in Non-Patent Document 3 are limited to polyimide raw materials. Including the above-mentioned Non-Patent Documents 1 and 2 and Patent Documents 1 to 12, there have been no examples of examining cyclobutanedicarboxylic acid esters as a raw material for polyimide in relation to a catalyst for olefin polymerization.

However, the present inventor, apart from the conventional knowledge, recalled the possibility that the cyclobutane dicarboxylic acid esters could replace the phthalate electron donor of the conventional Ziegler-Natta catalyst. Therefore, the present inventor has verified the effectiveness of cyclobutanedicarboxylic acid esters as an electron donor for Mg / Ti catalysts.

As a result, it was surprisingly discovered that cyclobutanedicarboxylic acid esters are effective as electron donors for Mg / Ti catalysts and belong to a novel non-phthalate donor that has been industrially sought after in recent years. That is, the present invention is as follows.

(Invention 1) (A) A solid catalyst component of a catalyst for olefin polymerization, which is obtained by contacting a magnesium compound, a titanium compound, and cyclobutanedicarboxylic acid esters as electron donors.
(Invention 2) A catalyst for olefin polymerization, which comprises the above (A) solid catalyst component, (B) organoaluminum compound, and (C) external electron donor.
(Invention 3) A method for producing a polyolefin, wherein the olefins are polymerized in the presence of the olefin polymerization catalyst of the invention 2.
(Invention 4) A polyolefin obtained by the method for producing a polyolefin according to Invention 3.

The flowchart which shows typically the method of preparing the catalyst for olefin polymerization of this invention. SEM image (40 times) of the solid catalyst component (A) obtained in Example 1. SEM image (100 times) of the solid catalyst component (A) obtained in Example 1. SEM image (1000 times) of the solid catalyst component (A) obtained in Example 1. SEM image (10000 times) of the solid catalyst component (A) obtained in Example 1.

[(A) Solid catalyst component]
The solid catalyst component (A) (hereinafter, "(A) solid catalyst component") of the catalyst for olefin polymerization of the present invention is brought into contact with a magnesium compound, a titanium compound, and cyclobutanedicarboxylic acid esters as electron donors. Prepared. The solid catalyst component (A) of the present invention is a novel solid catalyst component of an olefin polymerization catalyst in that it contains cyclobutane dicarboxylic acid esters that have not been conventionally used as electron donors.

The solid catalyst component of the olefin polymerization catalyst is prepared by contacting the magnesium compound, the titanium compound and the electron donor, and the atoms derived from the magnesium compound, the titanium compound and the electron donor constitute the inside and the surface layer of the solid catalyst component. At present, it is impossible to express the situation in a uniform form such as a chemical formula or a composition formula.

Examples of the magnesium compound used for the preparation of the solid catalyst component (A) of the present invention include magnesium halide, dialkylmagnesium, alkylmagnesium halide, dialkoxymagnesium, diallyloxymagnesium, alkoxymagnesium halide and magnesium fatty acid. Can be used.

As the magnesium halide, for example, magnesium chloride, magnesium bromide, magnesium iodide and magnesium fluoride can be used.

As the dialkylmagnesium, for example, dimethylmagnesium, diethylmagnesium, ethylmethylmagnesium, dipropylmagnesium, methylpropylmagnesium, ethylpropylmagnesium, dibutylmagnesium, butylmethylmagnesium, butylethylmagnesium and the like can be used. These dialkylmagnesiums may be obtained by reacting metallic magnesium with an alcohol in the presence of a halogen-containing compound.

As the above-mentioned alkyl magnesium halide, for example, ethyl magnesium chloride, propyl magnesium chloride, butyl magnesium chloride and the like can be used. These alkyl magnesium halides may be obtained by reacting metallic magnesium with a halogenated hydrocarbon or an alcohol.

As the dialkoxymagnesium or diaryloxymagnesium, for example, dimethoxymagnesium, diethoxymagnesium, dipropoxymagnesium, dibutoxymagnesium, diphenoxymagnesium, ethoxymethoxymagnesium, ethoxypropoxymagnesium, butoxyethoxymagnesium and the like can be used. .. As the halogenated alkoxymagnesium, for example, methoxymagnesium chloride, ethoxymagnesium chloride, propoxymagnesium chloride, butoxymagnesium chloride and the like can be used. As the fatty acid magnesium, for example, magnesium laurate, magnesium stearate, magnesium octanate, magnesium decanoate and the like can be used.

As the magnesium compound used for the preparation of the solid catalyst component (A) of the present invention, magnesium halide or dialkoxymagnesium is preferable, and magnesium chloride, diethoxymagnesium or dipropoxymagnesium is particularly preferable.

The magnesium compound can be used alone or in combination of two or more when preparing the solid catalyst component (A).

Further, in the preparation of (A) solid catalyst component, it is not always necessary to use the above magnesium compound as a starting material. For example, those obtained by reacting metallic magnesium and alcohol in the presence of a catalyst such as iodine at the time of preparing the solid catalyst component (A) may be used.

The titanium compound used for the preparation of the solid catalyst component (A) of the present invention is a tetravalent halogen-containing titanium compound such as titanium tetrahalide or alkoxy titanium halide. As the titanium tetrahalide, for example, TiCl ₄ , TiBr ₄ , and TiI ₄ can be used. Examples of the alkoxytitanium halide include Ti (OCH ₃ ) Cl ₃ , Ti (OC ₂ H ₅ ) Cl ₃ , Ti (OC ₃ H ₇ ) Cl ₃ , Ti (OC ₄ H ₉ ) Cl ₃ , and Ti (OCH). ₃ ) ₂ Cl ₂ , Ti (OC ₂ H ₅ ) ₂ Cl ₂ , Ti (OC ₃ H ₇ ) ₂ Cl ₂ , Ti (OC ₄ H ₉ ) ₂ Cl ₂ , Ti (OCH ₃ ) ₃ Cl, Ti (OC) ₂ H ₅ ) ₃ Cl, Ti (OC ₃ H ₇ ) ₃ Cl, Ti (OC ₄ H ₉ ) ₃ Cl and the like can be used. Among these, titanium tetrahalide is preferable, and TiCl ₄ is particularly preferable. One or more of the above titanium compounds can be used. The titanium compound may be diluted with an organic solvent such as an aromatic hydrocarbon such as toluene or xylene or an aliphatic hydrocarbon such as hexane or heptane.

In the preparation of the solid catalyst component (A) of the present invention, a tetraalkoxytitanium compound can be used in combination with the tetravalent halogen-containing titanium compound. As such a tetraalkoxytitanium compound, for example, tetraethoxytitanium, tetrabutoxytitanium and the like can be used.

Specifically, the cyclobutanedicarboxylic acid esters used as an electron donor (so-called internal donor) in the preparation of the solid catalyst component (A) of the present invention are produced by the [2 + 2] cycloaddition reaction in the presence of the following photoenergy. Cyclobutane-α-dicarboxylic acid (upper row) and cyclobutane-β-dicarboxylic acid (lower row) are silylated.

Such cyclobutane-α-dicarboxylic acids and cyclobutane-β-dicarboxylic acids include the following 16 isomers, and each derivative or isomer can be used alone or in combination of two or more. ..

The solid catalyst component (A) of the present invention can be prepared by contacting the above-mentioned magnesium compound, titanium compound, and cyclobutanedicarboxylic acid esters as electron donors. As this preparation method, a known method can be adopted without limitation.

This contact is preferably treated in the presence of a suitable organic solvent in view of ease of operation. Examples of the organic solvent used include saturated hydrocarbon compounds such as hexane, heptane and cyclohexane, aromatic hydrocarbon compounds such as benzene, toluene, xylene and ethylbenzene, and halogens such as orthodichlorobenzene, methylene chloride, carbon tetrachloride and dichloroethane. Examples thereof include chemical hydrocarbon compounds, and among them, aromatic hydrocarbon compounds having a boiling point of about 90 to 150 ° C. in a liquid state at room temperature, specifically, heptane, toluene, xylene, or ethylbenzene are preferably used.

The contact of each component is carried out while stirring in a container equipped with a stirrer in an inert gas atmosphere and in a state where water and the like are removed. The contact temperature may be in a relatively low temperature range near room temperature in the case of simply contacting and stirring and mixing, or in the case of dispersion or suspension for transformation treatment, but in the case of reacting after contact to obtain a product. The temperature range of 40 to 130 ° C. is preferable. If the temperature during the reaction is less than 40 ° C, the reaction does not proceed sufficiently, and as a result, the performance of the prepared solid catalyst component becomes insufficient, and if it exceeds 130 ° C, the carboxylic acid ester used is decomposed. There is an adverse effect such as remarkable evaporation of the solvent. The reaction time is 1 minute or longer, preferably 10 minutes or longer, and more preferably 30 minutes or longer.

In a typical method for preparing the solid catalyst component (A) of the present invention, first, the suspension is suspended in a dialkoxymagnesium-inert organic solvent, the suspension is reacted with titanium tetrachloride, and then the cyclobutanedicarboxylic acid is described. A compound selected from the esters is added and further reacted to obtain a solid component. After washing the solid component with an inert organic solvent, the solid catalyst component is prepared by contacting with titanium tetrachloride again in the presence of the inert organic solvent. In this way, the solid catalyst component (A) of the present invention is obtained.

When preparing the solid catalyst component (A) of the present invention, the amounts of the magnesium compound, titanium compound and electron donor used differ depending on the preparation method and cannot be unconditionally specified. For example, titanium per mol of magnesium compound. The compound is 0.5 to 100 mol, preferably 1 to 10 mol, and the electron donor is 0.01 to 10 mol, preferably 0.1 to 3 mol.

The solid catalyst component (A) prepared as described above is combined with the components (B) and (C) described later to form the catalyst for olefin polymerization of the present invention.

[(B) Organoaluminium compound]
As the (B) organoaluminum compound used in the present invention (hereinafter, “component (B)”), the organoaluminum compound conventionally used for preparing the Mg / Ti catalyst can be used without limitation. Such an organoaluminum compound is typically represented by the following general formula.

In the above formula, R ¹ represents an alkyl group having 1 to 4 carbon atoms, preferably an ethyl group or an isobutyl group, X represents a hydrogen atom, a chlorine atom, a bromine atom or an iodine atom, and m is 0 <m ≦ 3. Indicates a real number.

The compounds represented by the above formula are, for example, triethylaluminum, diethylaluminum chloride, triisobutylaluminum, diethylaluminum bromide, diethylaluminum hydride and the like. Of these, triethylaluminum and triisobutylaluminum are preferable. Further, as the component (B) of the present invention, two or more kinds of the above-mentioned organoaluminum compounds can be mixed and used.

[(C) External electron donor]
As the (C) external electron donor (hereinafter referred to as “component (C)”) used in the present invention, the external electron donor (external donor) conventionally used for the preparation of Mg / Ti catalysts shall be used without limitation. Can be done. Such a preferable compound as the component (C) of the present invention is an organosilicon compound represented by the following general formula, which has been conventionally used for preparing a high-performance Mg / Ti catalyst.

In the above formula, R ² represents an alkyl group having the same or different carbon atoms 1 to 12, a cycloalkyl group, a phenyl group, a vinyl group, an allyl group or an aralkyl group, and R ³ has the same or different carbon atoms 1 to 4 carbon atoms. Alkyl group, cycloalkyl group, phenyl group, vinyl group, allyl group or aralkyl group, and n represents an integer of 0 or 1 to 4.

The R ² is preferably an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group or a phenyl group, and the cycloalkyl group is preferably a cycloalkyl group having 3 to 6 carbon atoms, particularly preferably a cyclopentyl group or a cyclohexyl group. .. The preferred group of R ³ is an alkyl group having 1 to 4 carbon atoms, and a methyl group and an ethyl group are particularly preferable.
As such a component (C), phenylalkoxysilane, alkylalkoxysilane, phenylalkylalkoxysilane, cycloalkylalkoxysilane, cycloalkylalkylalkoxysilane, alkoxysilane and the like can be used. Examples of such compounds include trimethylmethoxysilane, trimethylethoxysilane, tri-n-propylmethoxysilane, tri-n-propylethoxysilane, tri-n-butylmethoxysilane, triisobutylmethoxysilane, and tri-t-butylmethoxy. Silane, tri-n-butylethoxysilane, tricyclohexylmethoxysilane, tricyclohexylethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, di-n-propyldimethoxysilane, diisopropyldimethoxysilane, di-n-propyldiethoxysilane, diisopropyl Diethoxysilane, di-n-butyldimethoxysilane, diisobutyldimethoxysilane, di-t-butyldimethoxysilane, di-n-butyldiethoxysilane, n-butylmethyldimethoxysilane, bis (2-ethylhexyl) dimethoxysilane, bis (2-Ethylhexyl) diethoxysilane, dicyclohexyldimethoxysilane, dicyclohexyldiethoxysilane, dicyclopentyldimethoxysilane, dicyclopentyldiethoxysilane, cyclohexylmethyldimethoxysilane, cyclohexylmethyldiethoxysilane, cyclohexylethyldimethoxysilane, cyclohexyl (isopropyl) dimethoxy Silane, cyclohexylethyldiethoxysilane, cyclopentylmethyldimethoxysilane, cyclopentylmethyldiethoxysilane, cyclopentylethyldiethoxysilane, cyclopentyl (isopropyl) dimethoxysilane, cyclohexyl (n-pentyl) dimethoxysilane, cyclohexyl (n-pentyl) diethoxysilane , Cyclopentyl (isobutyl) dimethoxysilane, cyclohexyl (n-propyl) dimethoxysilane, cyclohexyl (n-propyl) diethoxysilane, cyclohexyl (isopropyl) diethoxysilane, cyclohexyl (n-butyl) dimethoxysilane, cyclohexyl (n-butyl) Diethoxysilane, cyclohexyl (isobutyl) dimethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, phenylmethyldimethoxysilane, phenylmethyldiethoxysilane, phenylethyldimethoxysilane, phenylethyldiethoxysilane, cyclohexyldimethylmethoxysilane, cyclohexyldimethylethoxy Silane, cyclohexyldiethylmethoxysilane, cyclo Hexyldiethylethoxysilane, 2-ethylhexyltrimethoxysilane, 2-ethylhexyltriethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, n-propyltrimethoxysilane, n-propyltri Ethoxysilane, isopropyltrimethoxysilane, isopropyltriethoxysilane, n-butyltrimethoxysilane, isobutyltrimethoxysilane, t-butyltrimethoxysilane, n-butyltriethoxysilane, cyclohexyltrimethoxysilane, cyclohexyltriethoxysilane, cyclopentyl Trimethoxysilane, cyclopentyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 2-ethylhexyltrimethoxysilane, 2-ethylhexyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, tetramethoxysilane, tetraethoxysilane , Cyclohexylcyclopentyldimethoxysilane, cyclohexylcyclopentyldiethoxysilane, cyclohexylcyclopentyldipropoxysilane, 3-methylcyclohexylcyclopentyldimethoxysilane, 4-methylcyclohexylcyclopentyldimethoxysilane, 3,5-dimethylcyclohexylcyclopentyldimethoxysilane, 3-methylcyclohexylcyclohexyldimethoxy. Silane, bis (3-methylcyclohexyl) dimethoxysilane, 4-methylcyclohexylcyclohexyldimethoxysilane, bis (4-methylcyclohexyl) dimethoxysilane, 3,5-dimethoxycyclohexylcyclohexyldimethoxysilane and bis (3,5-dimethylcyclohexyl) dimethoxy Examples include silane.

Of these, triethoxysilanes such as ethyltriethoxysilane and cyclohexyltriethoxysilane, di-n-propyldimethoxysilane, diisopropyldimethoxysilane, di-n-butyldimethoxysilane, diisobutyldimethoxysilane, and di-t-butyldimethoxy Silane, di-n-butyldiethoxysilane, t-butyltrimethoxysilane, dicyclohexyldimethoxysilane, dicyclohexyldiethoxysilane, cyclohexylmethyldimethoxysilane, cyclohexylmethyldiethoxysilane, cyclohexylethyldimethoxysilane, cyclohexylethyldiethoxysilane, di Cyclopentyldimethoxysilane, dicyclopentyldiethoxysilane, cyclopentylmethyldimethoxysilane, cyclopentylmethyldiethoxysilane, cyclopentylethyldiethoxysilane, cyclohexylcyclopentyldimethoxysilane, cyclohexylcyclopentyldiethoxysilane, 3-methylcyclohexylcyclopentyldimethoxysilane, 4-methylcyclohexyl Cyclopentyldimethoxysilane, 3,5-dimethylcyclohexylcyclopentyldimethoxysilane is preferably used. As such a component (C), two or more kinds selected from the above-mentioned compounds can also be used.

[Catalyst for olefin polymerization]
The olefin polymerization catalyst of the present invention is a novel olefin polymerization catalyst containing the above-mentioned novel (A) solid catalyst component, component (B), and component (C). The ratio of the amount of each component used is arbitrary as long as it does not affect the effect of the present invention, and is not particularly limited. , 1-2000 mol, preferably 50-1000 mol. The component (C) is used in the range of 0.001 to 10 mol, preferably 0.002 to 2 mol, particularly preferably 0.002 to 0.5 mol, per 1 mol of the component (B).

Although the contact order of each component is arbitrary, it is desirable that (B) an organoaluminum compound is first added to the polymerization system, and then (A) a solid catalyst component for olefin polymerization is brought into contact. Typically, (B) an organoaluminum compound is first inserted into the polymerization system, then (C) an external electron donor component is contacted, and then a solid catalyst component (A) for olefin polymerization is contacted.

[polymerization]
Polymerization or copolymerization of olefins is carried out in the presence of the catalyst for polymerization of olefins of the present invention. Since the catalyst for olefin polymerization of the present invention has a substantially uniform spherical morphology, it is possible to produce a polyolefin having high particle morphology uniformity. Examples of the olefins include ethylene, propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, vinylcyclohexane and the like, and these olefins can be used alone or in combination of two or more. In particular, ethylene, propylene and 1-butene are preferably used. Particularly preferred is propylene. In the case of propylene, copolymerization with other olefins can also be performed. Examples of the olefins to be copolymerized include ethylene, 1-butene, 1-pentene, 4-methyl-1-pentene, vinylcyclohexane and the like, and these olefins can be used alone or in combination of two or more. In particular, ethylene and 1-butene are preferably used. The copolymerization of propylene and other olefin monomers includes random copolymerization in which propylene and a small amount of ethylene are used as comonomer in one stage and propylene homopolymerization in the first stage (first polymerization tank). A typical example is so-called propylene-ethylene block copolymerization in which propylene and ethylene are copolymerized in a second stage (second polymerization tank) or a higher number of stages (multi-stage polymerization tank). Even in such random copolymerization and block copolymerization, the catalyst of the present invention composed of the above-mentioned components (A), (B), or (C) is effective, and has good catalytic activity and stereoregularity. Not only does it give a polymer or copolymer with a wide molecular weight distribution.

The polymerization method in the present invention can be carried out in the presence or absence of an organic solvent, and an olefin monomer such as propylene can be used in either a gas or liquid state. The polymerization temperature is 200 ° C. or lower, preferably 100 ° C. or lower, and the polymerization pressure is 10 MPa or less, preferably 6 MPa or less. Further, either a continuous polymerization method or a batch type polymerization method is possible. Further, the polymerization reaction may be carried out in one stage or in two or more stages.

Further, in the present invention, when polymerizing an olefin using a catalyst containing the solid catalyst components (A), (B), and (C) for olefin polymerization (also referred to as main polymerization), the catalytic activity and three-dimensionality. In order to further improve the regularity and the particle properties of the polymer to be produced, it is desirable to perform prepolymerization prior to the main polymerization. In the prepolymerization, the same monomers as in the main polymerization, such as olefins or styrene, can be used.

When performing the prepolymerization, the contact order of each component and the monomer is arbitrary, but preferably, the component (B) is first charged into the prepolymerization system set to an inert gas atmosphere or an olefin gas atmosphere, and then the olefin. After contacting the solid catalyst component (A) for polymerization, an olefin such as propylene and / or one or more other olefins are contacted. Typically, the component (B) is first charged into the prepolymerization system set to an inert gas atmosphere or an olefin gas atmosphere, then the component (C) is brought into contact with the component (C), and then the solid catalyst component for olefin polymerization (A). ), And then contacting an olefin such as propylene and / or one or two or more other olefins is desirable.

[Polyolefin]
Polyolefins with high stereoregularity and good particle shape in high yields equal to or higher than those using conventional high-performance Mg / Ti catalysts by polymerization using the olefin polymerization catalyst of the present invention. Is manufactured. The polyolefin of the present invention is a novel polyolefin in that it contains a residue of a novel catalyst for olefin polymerization. Although the polyolefin of the present invention is novel as a chemical substance, it is technically impossible to express its structure by a chemical formula or a general formula, so that the polyolefin of the present invention must be defined by its production method.

The polyolefin of the present invention is used in a wide range of industrial products as various molding materials. In particular, polypropylenes obtained by (co) polymerizing propylene in the presence of the olefin polymerization catalyst of the present invention have high stereoregularity and exhibit a uniform particle size, so that they have mechanical strength and processability. Excellent for.

[Synthesis of α-torxyl acid dibutyl ester]
The α-torxylate dibutyl ester was synthesized by the following reaction route.

(Step a) Trans-cinnamic acid was photodimerized by irradiating 1.0 g of trans-cinnamic acid dispersed in 20 ml of heptane with ultraviolet rays using a 100 W mercury lamp for 48 hours. The product was recrystallized in ethanol to give α-torxylic acid (2). (Step b) In the presence of 275 mg of chlorotrimethylsilane, 500 mg of α-torxylic acid (2) was microwave-heated at 110 ° C. for 20 minutes in 6.6 ml of n-butanol, and then crystallized at room temperature. In this way, the desired α-torxylate dibutyl ester (3) was obtained.

[Preparation of solid catalyst component (A)]
To 16 ml of dehydrated toluene in which 2.0 g of ₂ particles of Mg (OC ₂ H ₅ ) were dispersed, 8 ml of a TiCl ₄ / toluene solution (volume ratio 1: 1 mixed solution) was added dropwise while maintaining 0 ° C. to 5 ° C. The temperature of the obtained dispersion was raised to 90 ° C., and 2.5 ml of a toluene solution in which 0.845 g of α-torxylate dibutyl ester (3) was dissolved was added thereto. The liquid temperature was heated to 110 ° C. and reacted for 2 hours. The obtained powder was decantated twice with 16 ml of toluene heated to 90 ° C., and further 8 ml of a TiCl ₄ / toluene solution (volume ratio 1: 1 mixed solution) was added and reacted at 110 ° C. for 2 hours. After completion of the reaction, the mixture was decanted 3 times with 20 ml of toluene heated to 110 ° C. and 4 times with 16 to 20 ml of heptane at room temperature, and vacuum dried. In this way, the solid catalyst component (A-1) of the present invention was obtained.

FIGS. 2 to 5 show SEM (Hitachi S-4100, 20 kV) images of the obtained solid catalyst component (A-1). The observed particle morphology is subspherical, similar to the morphology of the raw material Mg (OC ₂ H ₅ ) ₂ particles. For this reason, the α-torxylate dibutyl ester (3) used as the electron donor (internal donor) in the present invention provides a solid catalyst component in a good form similar to the conventionally used dibutyl phthalate (DBP). You can see that.

The median system (D ₅₀ ) of the solid catalyst component (A-1) was 43.9 μm. R. of the solid catalyst component (A-1). S. F (Relativr Span Factor): (D _90- D ₁₀ ) / D ₅₀ (D ₉₀ is the diameter corresponding to the cumulative 90% by volume from the small particle side of the cumulative particle size distribution, and D ₁₀ is the diameter corresponding to the cumulative 10% by volume. , D ₅₀ represents the median diameter.) Was 0.43. From this, it can be seen that the solid catalyst component (A-1) has a relatively uniform particle size.

The α-torxylate dibutyl ester (3) content of the solid catalyst component (A-1) was 14.7% by weight. The DBP content of a general solid catalyst component using dibutyl phthalate (DBP) is about 14% by weight, and from this as well, the α-torxylate dibutyl ester (3) has an electron donor function corresponding to DBP. It is presumed that it exerted.

[Preparation of catalyst for olefin polymerization, propylene polymerization]
Under a nitrogen atmosphere and mechanical stirring at 350 rpm, 200 ml of heptane filled in a 1 L stainless steel container maintained at 50 ° C. was saturated with 0.5 MPa of propylene. To this, 3.0 mmol of triethylaluminum (B-1), 0.2 mmol of cyclohexylmethyldimethoxysilane (C-1), a solid catalyst component (A-1), and 100 ml of additional heptane were added in this order to initiate polymerization. .. The propylene pressure during the polymerization was maintained at 0.5 MPa. After 60 minutes from the start of the polymerization, the supply of propylene was stopped to complete the polymerization. Thus polypropylene was obtained.

The polymerization catalytic activity determined from the weight of the produced polypropylene is 0.51 kg-PP / g-cat · h, and this value is a general polymerization using dibutyl phthalate (DBP) as an internal donor under the same polymerization conditions. It is comparable to the activity of the catalyst.

The stereoregularity (mm mm) (measured at ¹³ CNMR, 100 MHz) of the obtained polypropylene was 85.7 mol%, and it was confirmed that the synthesis of isotactic polypropylene was successful.

As described above, cyclobutanedicarboxylic acid esters, which are biological compounds effective as raw materials for polyimide, such as α-torxylate dibutyl ester, are non-phthalate electron donors (internal donors) of Ziegler-Natta catalysts used in the production of polyolefins. ) Was confirmed to be effective for the first time. It was also confirmed that a highly stereoregular polypropylene that can withstand practical use can be produced in the presence of a Ziegler-Natta catalyst that actually uses α-torxylate dibutyl ester as an electron donor.

INDUSTRIAL APPLICABILITY According to the present invention, a novel and high-performance catalyst for olefin polymerization using a non-phthalate electron donor can be provided. The present invention has excellent industrial value in that it can expand a polyolefin production method that complies with recent compound regulations.

Claims (4)

(A) Solid catalyst component of a catalyst for olefin polymerization, which is obtained by contacting a magnesium compound, a titanium compound, and an ester compound of a silicate dimer having a cyclobutane structure as an electron donor. A catalyst for olefin polymerization, which comprises (A) a solid catalyst component, (B) an organoaluminum compound, and (C) an external electron donor according to claim 1. A method for producing a polyolefin, wherein the olefins are polymerized in the presence of the olefin polymerization catalyst according to claim 2. A polyolefin obtained by the method for producing a polyolefin according to claim 3.

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