Solid catalyst component mixture for olefin polymerization, catalyst for olefin polymerization, and method for producing olefin polymers

Abstract

To provide a solid catalyst component mixture for olefin polymerization, enabling the easy production of an olefin polymer that exhibits both high melt flowability and high stiffness.SOLUTION: Provided is a solid catalyst component mixture for olefin polymerization comprising a first solid catalyst component for olefin polymerization that contains magnesium, titanium, halogen, and a succinate diester compound and a second solid catalyst component for olefin polymerization that contains magnesium, titanium, halogen, and a phthalate diester compound in amounts such that the mass ratio of the first solid catalyst component for olefin polymerization to the second solid catalyst component for olefin polymerization ranges from 37: 63 to 87 : 13.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a solid catalyst component mixture for olefin polymerization, a catalyst for olefin polymerization, and a process for producing an olefin polymer. Background Art

[0002] In recent years, olefin polymers such as polypropylene (PP) have been used in various applications including molded articles for automobile parts and household electrical appliances, as well as containers, films and the like.

[0003] Polypropylene resin compositions are lightweight and excellent in moldability, and also have excellent chemical stability such as heat resistance and chemical resistance in molded articles, and are also very excellent in cost performance. Therefore, they are used in many fields as one of the most important plastic materials.

[0004] In order to further expand applications, polypropylene that can be used as a substitute for polystyrene and ABS resins, has high melt flowability (melt flow rate (MFR)), excellent moldability, and excellent flexural modulus (FM) has been desired.

[0005] In the polymerization of olefins such as propylene, a polymerization method using a solid catalyst component containing magnesium atoms, titanium atoms, halogen atoms and an internal electron-donating compound as essential components is known. Many methods have been proposed for polymerizing or copolymerizing olefins in the presence of an olefin polymerization catalyst composed of the above solid catalyst component, an organoaluminum compound and an organosilicon compound (see Patent Document 1, etc.).

[0006] For example, Patent Document 1 proposes a method for polymerizing propylene using an olefin polymerization catalyst including a solid titanium catalyst component supporting an internal electron donating compound such as a phthalate ester, an organoaluminum compound as a cocatalyst component, and an organosilicon compound having at least one Si-O-C bond. In many documents including Patent Document 1, a method of using a phthalate ester as an internal electron donating compound to obtain a highly stereoregular polymer with high polymerization activity has been proposed. [Prior Art Documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Laid-Open No. 57-63310 [Patent Document 2] Japanese Patent Laid-Open No. 2000-017019 [Summary of the Invention] [Problem to be Solved by the Invention]

[0008] However, in recent years, there has been a growing demand for a solid catalyst component for olefin polymerization that can produce polypropylene having a more excellent flexural modulus (FM) than the case of using a solid catalyst component containing a phthalate ester as an internal electron donating compound, specifically polypropylene having a high flexural modulus (FM) of 1900 MPa or more.

[0009] As a result of intensive studies conducted by the present inventors to solve the above technical problem, they have found that by employing a solid catalyst component for olefin polymerization containing a succinic acid diester compound as an internal electron donating compound, polypropylene having a high flexural modulus (FM) of 1900 MPa or more and excellent rigidity can be produced.

[0010] On the other hand, as described above, as a solid catalyst component for olefin polymerization, there is a demand for a catalyst component that can produce an olefin polymer having high flexural modulus (FM), excellent rigidity, high melt flow property (melt flow rate (MFR)) and excellent moldability. However, in olefin polymers obtained using catalysts for olefin polymerization (including solid catalyst components for olefin polymerization), melt flow rate (MFR) and flexural modulus (FM) generally have a trade-off relationship. Even when polypropylene with a flexural modulus (FM) of 1900 MPa or higher is produced using a solid catalyst component for olefin polymerization containing the above succinate diester compound as an internal electron-donating compound, the resulting polypropylene tends to have an extremely low melt flow rate (MFR).

[0011] In order to obtain olefin polymers with high flexural modulus (FM) and melt flow rate (MFR), a method of mixing multiple types of olefin polymers is also conceivable. That is, a method of first producing an olefin polymer with high melt flow rate and an olefin polymer with high flexural modulus separately, and then mixing them. However, when mixing multiple types of olefin polymers, polymers with significantly different physical properties generally tend not to mix well. Furthermore, depending on the olefin polymers to be mixed, special mixing equipment with superior stirring power may be required during mixing, resulting in significant energy costs and an increased number of process steps. This presents technical challenges in easily producing olefin polymers with desired properties.

[0012] Thus, until now, no solid catalyst component for olefin polymerization had been known that could produce olefin polymers with high melt flowability (melt flow rate (MFR)) of 80-120 g / 10 min, excellent moldability, and high rigidity with a flexural modulus (FM) of 1900 MPa or more.

[0013] Under these circumstances, the present invention aims to provide a technical means for easily producing olefin polymers that achieve both high melt flowability and rigidity. [Means for solving the problem]

[0014] In order to solve the above technical problems, the inventors conducted extensive research and found that the above technical problems can be solved by using a solid catalyst component mixture for olefin polymerization, which is obtained by mixing a first solid catalyst component for olefin polymerization containing magnesium, titanium, halogen, and succinate diester compound with a second solid catalyst component for olefin polymerization containing magnesium, titanium, halogen, and phthalate diester compound in a predetermined ratio. Based on this finding, the present invention was completed.

[0015] In other words, the present invention is (i) A first solid catalyst component for olefin polymerization comprising magnesium, titanium, halogen, and succinate diester compound, A second solid catalyst component for olefin polymerization containing magnesium, titanium, halogen, and phthalate diester compounds, The solid catalyst components for polymerization of olefins are included in a mass ratio of 37:63 to 87:13 for the first solid catalyst component for polymerization of olefins and the second solid catalyst component for polymerization. A mixture of solid catalyst components for olefin polymerization, characterized by the following: (ii) The solid catalyst component mixture for olefin polymerization described in (i) above, wherein the content of the succinate diester compound is 4.7 to 14.9% by mass on a solid content basis. (iii) A solid catalyst component mixture for olefin polymerization according to (i) or (ii) above, wherein the content of the phthalate diester compound is 2.2 to 7.9% by mass on a solid content basis. (iv)(I) A mixture of solid catalyst components for olefin polymerization described in any of (i) to (iii) above and (II) General formula (1) below R 1 p AlQ 3-p (1) (In the formula, R 1 Q is an alkyl group having 1 to 6 carbon atoms, Q is a hydrogen atom or a halogen atom, and p is 0 <p≦3であり、R 1 If there are multiple R 1may be the same or different from each other, and when a plurality of Q are present, each Q may be the same or different from each other.) one or more organoaluminum compounds selected from the compounds represented by A catalyst for olefin polymerization characterized by comprising (v) (I) The solid catalyst component mixture for olefin polymerization according to any one of (i) to (iii) above, (II) the following general formula (1) R 1 p AlQ 3-p (1) (wherein, R 1 is an alkyl group having 1 to 6 carbon atoms, Q is a hydrogen atom or a halogen atom, p is 0 < p ≦ 3, R 1 when a plurality of are present, each R 1 may be the same or different from each other, and when a plurality of Q are present, each Q may be the same or different from each other.) one or more organoaluminum compounds selected from the compounds represented by and (III) an external electron donor compound The catalyst for olefin polymerization according to (iv) above, which comprises (vi) A method for producing an olefin polymer, characterized in that olefins are polymerized using the catalyst for olefin polymerization according to (iv) or (v) above, which is provided by the present invention. [Effects of the Invention]

[0016] According to the present invention, there can be provided a solid catalyst component mixture for olefin polymerization that can easily produce an olefin polymer having both high melt flowability and rigidity, and a catalyst for olefin polymerization and a method for producing an olefin polymer can also be provided. [Brief Description of Drawings]

[0017] [Figure 1] It is a figure for explaining the preparation method of a measurement sample for measuring the ratio of an oriented layer in the cross section of an injection-molded plate of an olefin polymer. [Figure 2] This diagram illustrates a method for preparing a sample for measuring the proportion of the orientation layer in the cross-section of an injection-molded sheet of an olefin polymer. [Figure 3] This diagram illustrates a method for determining the proportion of the orientation layer. [Figure 4] This figure shows polarized microscope images of measurement samples prepared to measure the proportion of the orientation layer in the cross-section of an injection-molded sheet of an olefin polymer. [Figure 5] This figure shows polarized microscope images of measurement samples prepared to measure the proportion of the orientation layer in the cross-section of an injection-molded sheet of an olefin polymer. [Figure 6] This figure shows polarized microscope images of measurement samples prepared to measure the proportion of the orientation layer in the cross-section of an injection-molded sheet of an olefin polymer. [Figure 7] This figure shows polarized microscope images of measurement samples prepared to measure the proportion of the orientation layer in the cross-section of an injection-molded sheet of an olefin polymer. [Figure 8] This figure shows polarized microscope images of measurement samples prepared to measure the proportion of the orientation layer in the cross-section of an injection-molded sheet of an olefin polymer. [Figure 9] This figure shows polarized microscope images of measurement samples prepared to measure the proportion of the orientation layer in the cross-section of an injection-molded sheet of an olefin polymer. [Figure 10] This figure shows polarized microscope images of measurement samples prepared to measure the proportion of the orientation layer in the cross-section of an injection-molded sheet of an olefin polymer. [Modes for carrying out the invention]

[0018] First, the solid catalyst component mixture for olefin polymerization according to the present invention will be described. The solid catalyst component mixture for olefin polymerization according to the present invention comprises a first solid catalyst component for olefin polymerization containing magnesium, titanium, halogen, and succinate diester compound, A second solid catalyst component for olefin polymerization containing magnesium, titanium, halogen, and phthalate diester compounds, The solid catalyst components for polymerization of olefins are included in a mass ratio of 37:63 to 87:13 for the first solid catalyst component for polymerization of olefins and the second solid catalyst component for polymerization. It is characterized by the following:

[0019] The solid catalyst component mixture for olefin polymerization according to the present invention includes a first solid catalyst component for olefin polymerization. The first solid catalyst component for olefin polymerization that constitutes the solid catalyst component mixture for olefin polymerization according to the present invention is a catalytic reaction product obtained by bringing raw material components that serve as sources of magnesium, titanium, and halogens into contact with a succinic acid diester compound, which is an internally electron-donating compound, in an organic solvent and reacting them. Specifically, a catalytic reaction product can be obtained by using a magnesium compound and a tetravalent titanium halogen compound as raw material components that serve as sources of magnesium, titanium, and halogens, and bringing these raw materials into contact with an internally electron-donating compound containing a succinic acid diester compound.

[0020] Examples of the above magnesium compounds include one or more selected from dialkoxymagnesium, magnesium dihalides, and alkoxymagnesium halides. Among the magnesium compounds mentioned above, dialkoxymagnesium or magnesium dihalide is preferred. Specifically, examples include dimethoxymagnesium, diethoxymagnesium, dipropoxymagnesium, dibutoxymagnesium, ethoxymethoxymagnesium, ethoxypropoxymagnesium, butoxyethoxymagnesium, magnesium dichloride, magnesium dibromide, magnesium diodide, and the like, with diethoxymagnesium and magnesium dichloride being particularly preferred.

[0021] Among the magnesium compounds mentioned above, dialkoxymagnesium may be obtained by reacting metallic magnesium with an alcohol in the presence of a halogen or a halogen-containing metallic compound.

[0022] The above-mentioned dialkoxymagnesium is preferably in granular or powder form, and may be of an irregular shape or spherical.

[0023] When spherical dialkoxymagnesium is used, a polymer powder with a better particle shape (more spherical) and a narrower particle size distribution can be obtained, improving the handling of the polymer powder generated during the polymerization operation and suppressing the occurrence of blockages and other issues caused by fine particles contained in the generated polymer powder.

[0024] The spherical dialkoxymagnesium mentioned above does not necessarily have to be perfectly spherical; elliptical or potato-shaped forms can also be used.

[0025] Furthermore, the average particle size (average particle size D50) of the above-mentioned dialkoxymagnesium is preferably 1.0 to 200.0 μm, and more preferably 5.0 to 150.0 μm. Here, the average particle size D50 refers to the particle size that accounts for 50% of the integrated particle size distribution in the volume integrated particle size distribution when measured using a laser light scattering diffraction particle size analyzer. When the dialkoxymagnesium is spherical, the average particle size D50 is preferably 1.0 to 100.0 μm, more preferably 5.0 to 80.0 μm, and even more preferably 10.0 to 70.0 μm.

[0026] Furthermore, regarding the particle size distribution of dialkoxymagnesium, it is preferable to have a narrow particle size distribution with few fine and coarse particles. Specifically, when measuring the diameter of dialkoxymagnesium using a laser scattering diffraction particle size analyzer, it is preferable that 20% or less of the particles have a diameter of 5.0 μm or less, and more preferably 10% or less. On the other hand, when measuring the diameter of dialkoxymagnesium using a laser scattering diffraction particle size analyzer, it is preferable that 20% or less of the particles have a diameter of 100.0 μm or more, and more preferably 10% or less. Furthermore, when the particle size distribution is expressed as ln(D90 / D10), it is preferably 3 or less, and more preferably 2 or less. Here, D90 represents the particle size that accounts for 90% of the integrated particle size distribution in the volume integrated particle size distribution when measured using a laser light scattering diffraction particle size analyzer. D10 represents the particle size that accounts for 10% of the integrated particle size distribution in the volume integrated particle size distribution when measured using a laser light scattering diffraction particle size analyzer.

[0027] Methods for producing the above-mentioned spherical dialkoxymagnesium are exemplified in, for example, Japanese Patent Publication No. 62-51633, Japanese Patent Publication No. 3-74341, Japanese Patent Publication No. 4-368391, Japanese Patent Publication No. 8-73388, and the like.

[0028] In the solid catalyst component for olefin polymerization according to the present invention, the magnesium compound has a specific surface area of ​​5 m². 2 Preferably, it is 5 to 50 m 2 It is more preferable that the value is / g, and 10-40m 2 A value of / g is even more preferable. By using a magnesium compound with a specific surface area within the above range, a solid catalyst component for olefin polymerization having a desired specific surface area can be easily prepared.

[0029] In this application, the specific surface area of ​​the magnesium compound refers to the value measured by the BET method. Specifically, the specific surface area of ​​the magnesium compound is the value measured by the BET method (automatic measurement) using a Mounttech Automatic Surface Area Analyzer HM model-1230 in the presence of a mixed gas of nitrogen and helium, after the sample has been vacuum-dried at 50°C for 2 hours.

[0030] The above magnesium compound is preferably in solution or suspension form during the reaction, as this allows the reaction to proceed smoothly.

[0031] If the magnesium compound is a solid, it can be dissolved in a solvent that has the ability to solubilize magnesium compounds to obtain a solution of the magnesium compound, or it can be suspended in a solvent that does not have the ability to solubilize magnesium compounds to obtain a suspension of the magnesium compound. Furthermore, if the magnesium compound is in liquid form, it may be used as is in solution form, or it may be further dissolved in a solvent that has the ability to solubilize magnesium compounds before being used in solution form.

[0032] Compounds capable of solubilizing solid magnesium compounds include at least one compound selected from the group consisting of alcohols, ethers, and esters, with alcohols such as ethanol, propanol, butanol, and 2-ethylhexanol being preferred, and 2-ethylhexanol being particularly preferred. On the other hand, examples of media that do not have the ability to solubilize solid magnesium compounds include one or more saturated hydrocarbon solvents or unsaturated hydrocarbon solvents that do not dissolve magnesium compounds.

[0033] In the solid catalyst component for olefin polymerization that constitutes the catalyst for olefin polymerization according to the present invention, the tetravalent titanium halogen compound, which is a raw material component that serves as a source of titanium and halogen, is not particularly limited, but the following general formula (2) Ti(OR 2 ) r X 4-r (2) (In the formula, R 2 It is preferable that the compound is one or more compounds selected from the titanium halide or alkoxy titanium halide group represented by (where represents an alkyl group having 1 to 4 carbon atoms, X represents a halogen atom such as a chlorine atom, a bromine atom, or an iodine atom, and r is 0 ≤ r ≤ 3).

[0034] In the general formula (2) above, r is 0 ≤ r ≤ 3, and specifically, r can be 0, 1, 2, or 3.

[0035] Examples of titanium halides represented by the above general formula (2) include one or more titanium tetrahalides selected from titanium tetrachloride, titanium tetrabromide, titanium tetraiodide, etc. Furthermore, the alkoxy titanium halide represented by the above general formula (2) can be one or more selected from methoxytitanium trichloride, ethoxytitanium trichloride, propoxytitanium trichloride, n-butoxytitanium trichloride, dimethoxytitanium dichloride, diethoxytitanium dichloride, dipropoxytitanium dichloride, di-n-butoxytitanium dichloride, trimethoxytitanium chloride, triethoxytitanium chloride, trippropoxytitanium chloride, tri-n-butoxytitanium chloride, etc. As the tetravalent titanium halogen compound, titanium tetrahalide is preferred, and titanium tetrachloride is more preferred. These titanium compounds may be used individually or in combination of two or more.

[0036] In the first solid catalyst component for olefin polymerization constituting the solid catalyst mixture for olefin polymerization according to the present invention, the succinate diester compound is the following general formula (3); [ka] (In the formula, R 3 and R 4 R is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and they may be the same or different from each other. 5 and R 6 (These are linear or branched alkyl groups having 2 to 4 carbon atoms, and may be the same or different from each other.) One or more compounds can be selected from those represented by [the formula shown].

[0037] In the compound represented by the above general formula (3), R 3 and R 4 These are hydrogen atoms or alkyl groups having 1 to 4 carbon atoms, and may be the same or different from each other. R 3 or R 4 When the alkyl group has 1 to 4 carbon atoms, specific examples include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, or an isobutyl group. In the compound represented by the above general formula (3), R 5 and R 6 These are linear alkyl groups or branched alkyl groups having 2 to 4 carbon atoms, and they may be the same or different from each other. R 5 and R 6 When the group is a linear alkyl group having 2 to 4 carbon atoms or a branched alkyl group, specific examples include an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, or an isobutyl group.

[0038] In the first solid catalyst component for olefin polymerization constituting the solid catalyst component mixture for olefin polymerization according to the present invention, the succinate diester compound is a dialkyl succinate represented by the above general formula (3), for example, Diethyl succinate, diethyl 2,3-dimethyl succinate, diethyl 2,3-diethyl succinate, diethyl 2,3-di-n-propyl succinate, diethyl 2,3-diisopropyl succinate, diethyl 2,3-di-n-butyl succinate, diethyl 2,3-diisobutyl succinate; Di-n-propyl succinate, di-n-propyl 2,3-dimethyl succinate, di-n-propyl 2,3-diethyl succinate, di-n-propyl 2,3-di-n-propyl succinate, di-n-propyl 2,3-diisopropyl succinate, di-n-propyl 2,3-di-n-butyl succinate, di-n-propyl 2,3-diisobutyl succinate; Diisopropyl succinate, diisopropyl 2,3-dimethylsuccinate, diisopropyl 2,3-diethylsuccinate, diisopropyl 2,3-di-n-propylsuccinate, diisopropyl 2,3-diisopropylsuccinate, diisopropyl 2,3-di-n-butylsuccinate, diisopropyl 2,3-diisobutylsuccinate; Di-n-butyl succinate, 2,3-dimethylsuccinate, 2,3-diethylsuccinate, 2,3-di-n-propylsuccinate, 2,3-diisopropylsuccinate, 2,3-di-n-butylsuccinate, 2,3-diisobutylsuccinate; Diisobutyl succinate, 2,3-dimethylsuccinate, 2,3-diethylsuccinate, 2,3-di-n-propylsuccinate, 2,3-diisopropylsuccinate, 2,3-di-n-butylsuccinate, 2,3-diisobutylsuccinate; You can list one or more types that can be selected from the list. Among these dialkyl succinate esters, diethyl succinate, di-n-propyl succinate, di-n-butyl succinate, diisobutyl succinate, 2,3-di-n-propyl succinate diethyl, 2,3-diisopropyl succinate diethyl, 2,3-di-n-propyl succinate di-n-propyl, 2,3-diisopropyl succinate di-n-propyl, 2,3-di-n-propyl succinate diisopropyl, 2,3-diisopropyl succinate diisopropyl, 2,3-di-n-propyl succinate di-n-butyl, 2,3-diisopropyl succinate di-n-butyl, 2,3-diisopropyl succinate diisobutyl, and 2,3-diisopropyl succinate diisobutyl are preferably used.

[0039] The first solid catalyst component for olefin polymerization that constitutes the solid catalyst component mixture for olefin polymerization according to the present invention preferably contains a succinate diester compound in a mass percentage of 5 to 28%, more preferably 10 to 24%, and even more preferably 15 to 20%, when calculated on a solid content basis. The first solid catalyst component for olefin polymerization that constitutes the solid catalyst component mixture for olefin polymerization according to the present invention preferably has a succinic acid diester compound content of 0.019 to 0.108 mol%, more preferably 0.039 to 0.093 mol%, and even more preferably 0.058 to 0.077 mol%, when calculated on a solid content basis.

[0040] The first solid catalyst component for olefin polymerization that constitutes the solid catalyst component mixture for olefin polymerization according to the present invention preferably has a ratio (D1 / T) of the content of succinate diester compound (D1) to the content of titanium (T) which is 3.5 to 6.6 by mass, more preferably 4.1 to 6.0, and even more preferably 4.8 to 5.4. The first solid catalyst component for olefin polymerization that constitutes the solid catalyst component mixture for olefin polymerization according to the present invention preferably has a molar ratio (D1 / T) of 0.3 to 1.3, more preferably 0.5 to 1.2, and even more preferably 0.7 to 1.1, where D1 is the ratio of the succinate diester compound to the titanium content (T).

[0041] In the first solid catalyst component for olefin polymerization that constitutes the solid catalyst component mixture for olefin polymerization according to the present invention, the ratio (D1 / T) of the content of the succinate diester compound (D1) to the content of titanium (T) when calculated on a solid content basis is within the above range, so that when subjected to polymerization of olefins, olefin polymers with excellent melt flow properties and even better flexural modulus can be easily produced.

[0042] The first solid catalyst component for olefin polymerization that constitutes the solid catalyst component mixture for olefin polymerization according to the present invention contains a succinic acid diester compound as an essential component as an internal electron-donating compound, but may also contain other internal electron-donating compounds (hereinafter referred to as "other internal electron-donating compounds" as appropriate).

[0043] Other internally electron-donating compounds include one or more selected from carbonates, acid halides, acid amides, nitriles, acid anhydrides, diether compounds, and carboxylic acid esters.

[0044] Examples of other internally electron-donating compounds include one or more selected from ether carbonate compounds, carboxylic acid diesters such as cycloalkane dicarboxylic acid diesters, cycloalkene dicarboxylic acid diesters, malonic acid diesters, alkyl-substituted malonic acid diesters, and maleic acid diesters, and diether compounds. More specifically, one or more selected from ether carbonate compounds such as (2-ethoxyethyl)methyl carbonate, (2-ethoxyethyl)ethyl carbonate, and (2-ethoxyethyl)phenyl carbonate; dialkylmalonic acid diesters such as dimethyl diisobutylmalonate and diethyl diisobutylmalonate; cycloalkanedicarboxylic acid diesters such as dimethyl cyclohexane-1,2-dicarboxylate; and 1,3-diethers such as (isopropyl)(isopentyl)-1,3-dimethoxypropane and 9,9-bis(methoxymethyl)fluorene are more preferred.

[0045] On the other hand, the first solid catalyst component for olefin polymerization constituting the solid catalyst component mixture for olefin polymerization according to the present invention is preferably such that the content of the phthalate diester compound is 0.2% by mass or less (0.0 to 0.2% by mass), more preferably 0.1% by mass or less (0.0 to 0.1% by mass), and even more preferably 0.0% by mass (substantially free of phthalate diester compounds (below the detection limit)).

[0046] In this application, the content ratio of succinate diester compounds, other internally electron-donating compounds added as needed, and (the content ratio of phthalate diester compounds described later) in the solid catalyst component for olefin polymerization refers to the value obtained by first heating and vacuum drying the solid catalyst component for olefin polymerization to completely remove the solvent component, then hydrolyzing it, and then extracting the succinate diester compounds, other internally electron-donating compounds added as needed, and phthalate diester compounds using an aromatic solvent, and measuring this solution by gas chromatography FID (Flame Ionization Detector). As stated above, in this application, "on a solid content basis" means calculating the content ratio of each component based on the solid content after completely removing liquid components such as solvents.

[0047] The first solid catalyst component for olefin polymerization constituting the solid catalyst component mixture for olefin polymerization according to the present invention preferably contains titanium in an amount of 2.0 to 5.0% by mass, more preferably 2.5 to 4.5% by mass, and even more preferably 3.5 to 4.5% by mass, on an atomic weight basis. The first solid catalyst component for olefin polymerization constituting the solid catalyst component mixture for olefin polymerization according to the present invention preferably contains magnesium in an amount of 15.0 to 25.0% by mass, more preferably 16.0 to 23.0% by mass, even more preferably 17.0 to 22.0% by mass, and even more preferably 17.0 to 21.0% by mass, on an atomic weight basis. The first solid catalyst component for olefin polymerization constituting the solid catalyst component mixture for olefin polymerization according to the present invention preferably contains halogen in an amount of 50.0 to 70.0% by mass on an atomic basis, more preferably 55.0 to 68.0% by mass, even more preferably 58.0 to 67.0% by mass, and most preferably 60.0 to 66.0% by mass.

[0048] In this application, the titanium atom content in the solid catalyst component for olefin polymerization refers to the value measured using the method described in JIS 8311-1997 "Method for Determining Titanium in Titanium Ore" (redox titration), with the solid catalyst component for olefin polymerization having been preheated and dried under reduced pressure to completely remove solvent components.

[0049] Furthermore, in this application, the magnesium atom content in the solid catalyst component for olefin polymerization refers to the value measured by the EDTA titration method, in which the solid catalyst component for olefin polymerization, which has been preheated and dried under reduced pressure to completely remove solvent components, is dissolved in hydrochloric acid solution and titrated with EDTA solution.

[0050] Furthermore, in this application, the halogen atom content in the solid catalyst component for olefin polymerization refers to the value measured by a silver nitrate titration method, in which a predetermined amount of the solid catalyst component for olefin polymerization, which has been preheated and dried under reduced pressure to completely remove solvent components, is treated with a mixed solution of sulfuric acid and pure water to obtain an aqueous solution, and then the halogen is titrated with a silver nitrate standard solution.

[0051] The first solid catalyst component for olefin polymerization that constitutes the solid catalyst component mixture for olefin polymerization in the present invention comprises magnesium, titanium, halogen, and succinate diester compounds, and optionally other internally electron-donating compounds, and may further contain polysiloxane.

[0052] In the present invention, the first solid catalyst component for olefin polymerization that constitutes the solid catalyst component mixture for olefin polymerization contains polysiloxane, which makes it possible to easily improve the stereoregularity or crystallinity of the polymer obtained when olefins are polymerized, and furthermore, to easily reduce the fine powder of the resulting polymer. Polysiloxanes are polymers that have siloxane bonds (-Si-O- bonds) in their main chain, and are also called silicone oils. They have a viscosity of 0.02 to 100.00 cm³ at 25°C. 2 / s (2-10,000 centistokes), more preferably 0.03-5.00 cm 2 It is a polysiloxane that is liquid or viscous at room temperature, in a chain-like, partially hydrogenated, cyclic, or modified form, with a length of s (3 to 500 centistokes).

[0053] Examples of linear polysiloxanes include dimethylpolysiloxane and methylphenylpolysiloxane; examples of partially hydrogenated polysiloxanes include methylhydrogenpolysiloxane with a hydrogenation rate of 10-80%; and examples of cyclic polysiloxanes include one or more selected from hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, 2,4,6-trimethylcyclotrisiloxane, and 2,4,6,8-tetramethylcyclotetrasiloxane.

[0054] The solid catalyst component mixture for olefin polymerization according to the present invention includes a second solid catalyst component for olefin polymerization along with the first solid catalyst component for olefin polymerization described above. A second solid catalyst component for olefin polymerization that constitutes the solid catalyst component mixture for olefin polymerization according to the present invention can be cited as a catalytic reaction product obtained by bringing raw material components that serve as sources of magnesium, titanium, and halogens into contact with a phthalate diester compound, which is an internally electron-donating compound, in an organic solvent and reacting them. Specifically, a catalytic reaction product can be cited in which a magnesium compound and a tetravalent titanium halogen compound are used as raw material components that serve as sources of magnesium, titanium, and halogens, and these raw materials are brought into contact with an internally electron-donating compound containing a phthalate diester compound.

[0055] Specific examples of the above-mentioned magnesium compounds and tetravalent titanium halogen compounds are the same as those listed in the description of the first solid catalyst component for olefin polymerization.

[0056] In the second solid catalyst component for olefin polymerization constituting the solid catalyst mixture for olefin polymerization according to the present invention, phthalate diesters are preferred as the phthalate diester compound. Examples of the phthalate diesters mentioned above include one or more selected from dimethyl phthalate, diethyl phthalate, di-n-propyl phthalate, diisopropyl phthalate, di-n-butyl phthalate, diisobutyl phthalate, methyl ethyl phthalate, (ethyl)n-propyl phthalate, ethylisopropyl phthalate, (ethyl)n-butyl phthalate, ethylisobutyl phthalate, and the like.

[0057] The second solid catalyst component for olefin polymerization that constitutes the solid catalyst component mixture for olefin polymerization according to the present invention preferably has a phthalate diester compound content of 8.0 to 20.0% by mass, more preferably 9.0 to 17.5% by mass, and even more preferably 10.0 to 15.0% by mass, when calculated on a solid content basis. The second solid catalyst component for olefin polymerization that constitutes the solid catalyst component mixture for olefin polymerization according to the present invention preferably has a phthalate diester compound content of 2.7 to 5.6 mol%, more preferably 3.6 to 5.3 mol%, and even more preferably 4.5 to 5.0 mol%, when calculated on a solid content basis.

[0058] The second solid catalyst component for olefin polymerization that constitutes the solid catalyst component mixture for olefin polymerization according to the present invention preferably has a ratio (D2 / T) of the content of phthalate diester compound (D2) to the content of titanium (T) which is 0.025 to 0.072 by mass, more preferably 0.030 to 0.063, and even more preferably 0.035 to 0.054. The second solid catalyst component for olefin polymerization that constitutes the solid catalyst component mixture for olefin polymerization according to the present invention preferably has a molar ratio (D2 / T) of 0.3 to 1.3, more preferably 0.5 to 1.2, and even more preferably 0.7 to 1.1, where D2 is the ratio of the phthalate diester compound to the titanium content (T).

[0059] In the second solid catalyst component for olefin polymerization that constitutes the solid catalyst component mixture for olefin polymerization according to the present invention, the ratio (D2 / T) of the phthalate diester compound content (D2) to the titanium content (T) when calculated on a solid content basis is within the above range, so that when subjected to polymerization of olefins, olefin polymers with excellent melt flow properties and even better flexural modulus can be easily produced.

[0060] The second solid catalyst component for olefin polymerization, which constitutes the solid catalyst component mixture for olefin polymerization according to the present invention, contains a phthalate diester compound as an essential component as an internal electron-donating compound. However, it may also contain other internal electron-donating compounds, and examples of such other internal electron-donating compounds are the same as those listed in the description of the first solid catalyst component for olefin polymerization above.

[0061] The second solid catalyst component for olefin polymerization, which constitutes the solid catalyst component for olefin polymerization according to the present invention, preferably contains a succinate diester compound of 0.2% by mass or less (0.0 to 0.2% by mass), more preferably 0.1% by mass or less (0.0 to 0.1% by mass), and even more preferably 0.0% by mass (substantially free of succinate diester (below the detection limit)).

[0062] The second solid catalyst component for olefin polymerization that constitutes the solid catalyst component mixture for olefin polymerization according to the present invention preferably contains titanium in an amount of 2.0 to 5.0% by mass, more preferably 2.5 to 4.5% by mass, and even more preferably 3.5 to 4.5% by mass, on an atomic weight basis. The second solid catalyst component for olefin polymerization that constitutes the solid catalyst component mixture for olefin polymerization according to the present invention preferably contains magnesium in an amount of 15.0 to 25.0% by mass on an atomic weight basis, more preferably 16.0 to 23.0% by mass, even more preferably 17.0 to 22.0% by mass, and even more preferably 17.0 to 21.0% by mass. The second solid catalyst component for olefin polymerization that constitutes the solid catalyst component mixture for olefin polymerization according to the present invention preferably contains halogen in an amount of 50.0 to 70.0% by mass on an atomic basis, more preferably 55.0 to 68.0% by mass, even more preferably 58.0 to 67.0% by mass, and most preferably 60.0 to 66.0% by mass.

[0063] The method for measuring the content ratio of each component of the second solid catalyst component for olefin polymerization described above is as described in the explanation of the first solid catalyst component for olefin polymerization.

[0064] The second solid catalyst component for olefin polymerization that constitutes the solid catalyst component mixture for olefin polymerization according to the present invention may contain a polysiloxane, and specific examples of polysiloxanes are the same as those described in the description of the first solid catalyst component for olefin polymerization.

[0065] The solid catalyst component mixture for olefin polymerization according to the present invention contains a first solid catalyst component for olefin polymerization and a second solid catalyst component for olefin polymerization in a mass ratio of first solid catalyst component for olefin polymerization: second solid catalyst component for olefin polymerization = 37:63 to 87:13, preferably 37:63 to 86:14, and more preferably 37:63 to 85:15. Furthermore, the solid catalyst component mixture for olefin polymerization according to the present invention means a mixture containing only the first solid catalyst component for olefin polymerization and the second solid catalyst component for olefin polymerization.

[0066] The solid catalyst component mixture for olefin polymerization according to the present invention contains the first solid catalyst component for olefin polymerization and the second solid catalyst component for olefin polymerization in the above proportions, thereby enabling the more effective production of olefin polymers that exhibit excellent melt flow properties and flexural modulus when subjected to olefin polymerization.

[0067] In the solid catalyst component mixture for olefin polymerization according to the present invention, a succinate diester compound is used as the internal electron-donating compound constituting the first solid catalyst component for olefin polymerization, while a phthalate diester compound is used as the internal electron-donating compound constituting the second solid catalyst component for olefin polymerization. In the solid catalyst component mixture for olefin polymerization according to the present invention, the content of the succinic acid diester compound is preferably 4.7 to 14.9% by mass, more preferably 4.7 to 14.6% by mass, and even more preferably 4.7 to 14.3% by mass, on a solid content basis. Furthermore, in the solid catalyst component mixture for olefin polymerization according to the present invention, the content of the phthalate diester compound is preferably 2.2 to 7.9% by mass, more preferably 2.3 to 7.9% by mass, and even more preferably 2.5 to 7.9% by mass, on a solid content basis. In the solid catalyst component mixture for olefin polymerization according to the present invention, the content ratios of succinate diester compounds and phthalate diester compounds are within the above ranges, thereby enabling the easy production of olefin polymers that exhibit both high melt flowability and rigidity when subjected to olefin polymerization.

[0068] Conventionally, succinate diester compounds were considered expensive and unsuitable for improving the stereoregularity of olefin polymers when used as internal electron-donating compounds in solid catalyst components for olefin polymerization. For these reasons, succinate diester compounds were not typically used as internal electron-donating compounds in solid catalyst components for olefin polymerization.

[0069] However, after diligent research by the present inventors, we have found that a solid catalyst component for olefin polymerization containing a succinic acid diester compound as an internal electron-donating compound can produce olefin polymers with excellent flexural modulus (FM) when subjected to the polymerization of olefins. On the other hand, according to the inventors' studies, it was found that when olefin polymers obtained using a solid catalyst component for olefin polymerization containing a succinic acid diester compound as an internal electron-donating compound are produced, the melt flow rate (MFR) of the resulting polypropylene tends to decrease drastically when producing polypropylene with a flexural modulus (FM) of 1900 MPa or higher. Under these circumstances, the present inventors have found that by adopting a first solid catalyst component for olefin polymerization that contains a succinate diester compound as an internally electron-donating compound, and a second solid catalyst component for olefin polymerization that uses a phthalate diester compound as an internally electron-donating compound, and by adopting a mixture containing the first and second solid catalyst components in predetermined proportions instead of the solid catalyst component of conventional olefin polymerization catalysts, it is possible to produce olefin polymers with a higher flexural modulus than conventional ones while ensuring excellent melt flowability when subjected to olefin polymerization, and have completed the present invention based on this finding.

[0070] A mixture of solid catalyst components for olefin polymerization containing multiple internally electron-donating compounds is thought to produce multiple olefin polymers when subjected to olefin polymerization, but since olefin polymers with significantly different physical properties generally do not mix well, it is generally difficult to put into practical use. On the other hand, in the solid catalyst component mixture for olefin polymerization according to the present invention, by subjecting a mixture containing a first solid catalyst component for olefin polymerization and a second solid catalyst component for olefin polymerization in predetermined proportions to the polymerization of olefins, the first solid catalyst component for olefin polymerization is thought to produce a first olefin polymer with excellent flexural modulus and a broad molecular weight distribution, and this first olefin polymer with a broad molecular weight distribution is thought to exhibit high compatibility with the second olefin polymer produced by the second solid catalyst component for olefin polymerization. The resulting olefin polymer (a mixture of the first and second olefin polymers) is thought to exhibit excellent melt flowability without significantly reducing the high flexural modulus exhibited solely by the first olefin polymer.

[0071] Thus, in the present invention, by employing a specific mixture of solid catalyst components for olefin polymerization instead of conventionally used solid catalyst components for olefin polymerization, it is possible to easily produce olefin polymers that have both high melt flowability and rigidity without requiring significant energy costs or increasing the number of process steps.

[0072] The solid catalyst component mixture for olefin polymerization according to the present invention may be prepared by pre-mixing the first solid catalyst component for olefin polymerization and the second solid catalyst component for olefin polymerization and using the mixture for olefin polymerization, or the first solid catalyst component for olefin polymerization and the second solid catalyst component for olefin polymerization may be separately charged into the olefin polymerization system and used as a mixture within the polymerization system.

[0073] The first solid catalyst component for olefin polymerization and the second solid catalyst component for olefin polymerization that constitute the solid catalyst component mixture for olefin polymerization according to the present invention can each be produced by conventionally known methods. The first solid catalyst component for olefin polymerization and the second solid catalyst component for olefin polymerization that constitute the solid catalyst component mixture for olefin polymerization according to the present invention differ in that they each contain either a succinate diester compound or a phthalate diester compound as an essential component as an internal electron-donating compound, but are common in other respects. Therefore, the methods for producing the first solid catalyst component for olefin polymerization and the second solid catalyst component for olefin polymerization also differ in that they each use either a succinate diester compound or a phthalate diester compound as an essential component as an internal electron-donating compound, but are common in other respects.

[0074] The first or second solid catalyst component for olefin polymerization constituting the solid catalyst component mixture for olefin polymerization according to the present invention is preferably prepared by bringing the above-mentioned dialkoxymagnesium, titanium halogen compound, and internal electron-donating compound (containing either a succinate diester compound or a phthalate diester compound as an essential component) into contact with each other in the presence of an inert organic solvent, as may be further necessary with other components.

[0075] In the present invention, the above-mentioned inert organic solvent is preferably one that dissolves titanium halogen compounds but does not dissolve dialkoxymagnesium. Specifically, one or more can be selected from saturated hydrocarbon compounds such as pentane, hexane, heptane, octane, nonane, decane, cyclohexane, methylcyclohexane, ethylcyclohexane, 1,2-diethylcyclohexane, methylcyclohexene, decalin, and mineral oil; aromatic hydrocarbon compounds such as benzene, toluene, xylene, and ethylbenzene; and halogenated hydrocarbon compounds such as orthodichlorobenzene, methylene chloride, 1,2-dichlorobenzene, carbon tetrachloride, and dichloroethane. As the above inert organic solvent, saturated hydrocarbon compounds or aromatic hydrocarbon compounds that are liquid at room temperature and have a boiling point of about 50 to 200°C are preferably used. In particular, one or more selected from hexane, heptane, octane, ethylcyclohexane, mineral oil, toluene, xylene, and ethylbenzene are preferred, and one or more selected from hexane, heptane, ethylcyclohexane, and toluene are especially preferred.

[0076] As a method for producing the solid catalyst component for olefin polymerization that constitutes the catalyst for olefin polymerization according to the present invention, when preparing a first solid catalyst component for olefin polymerization or a second solid catalyst component for olefin polymerization by bringing dialkoxymagnesium, a titanium halogen compound, and an internally electron-donating compound (containing either a succinate diester compound or a phthalate diester compound as an essential component) into contact with each other, The titanium halogen compound is brought into contact with the dialkoxymagnesium multiple times. When initially contacting the dialkoxymagnesium with the titanium halogen compound, use 1.5 to 10.0 moles of the titanium halogen compound per mole of dialkoxymagnesium. The total amount of titanium compound used is 5.0 to 18.0 moles per mole of dialkoxymagnesium. Furthermore, a method for obtaining a target solid catalyst component for olefin polymerization is provided, in which the amount of succinate diester compound or phthalate diester compound used per mole of dialkoxymagnesium is 0.10 to 0.20 moles (hereinafter referred to as method a for producing the solid catalyst component).

[0077] In method a for producing the solid catalyst component, the titanium halogen compound is brought into contact with dialkoxymagnesium multiple times. When the titanium halogen compound is brought into contact with dialkoxymagnesium for the first time, it is preferable to use 1.5 to 10.0 moles of the titanium halogen compound per mole of dialkoxymagnesium, 2.0 to 8.0 moles per mole of dialkoxymagnesium, and more preferably 2.0 to 5.0 moles per mole of dialkoxymagnesium.

[0078] In method a for producing the solid catalyst component, by controlling the amount of titanium halogen compound used relative to dialkoxymagnesium within the above range, a solid catalyst component for olefin polymerization that exhibits high activity with a small amount of titanium halogen compound can be prepared.

[0079] In method a for producing the solid catalyst component, the total amount of titanium compound used is 5.0 to 18.0 moles per mole of dialkoxymagnesium, preferably 5.0 to 15.0 moles per mole of dialkoxymagnesium, and more preferably 5.0 to 10.0 moles per mole of dialkoxymagnesium.

[0080] In method a for producing the solid catalyst component, by controlling the total amount of titanium compound used per mole of dialkoxymagnesium within the above range, it is possible to prepare a support that can optimally support titanium halogen compounds and succinate diester compounds while ensuring sufficiently high activity.

[0081] In method a for producing the solid catalyst component, it is preferable to use 0.10 to 0.20 moles of a succinate diester compound or a phthalate diester compound per mole of dialkoxymagnesium, 0.10 to 0.18 moles of a succinate diester compound or a phthalate diester compound per mole of dialkoxymagnesium, and more preferably 0.10 to 0.15 moles of a succinate diester compound or a phthalate diester compound per mole of dialkoxymagnesium.

[0082] In method a for producing the solid catalyst component, by controlling the amount of succinate diester compound or phthalate diester compound used per mole of dialkoxymagnesium within the above range, it is possible to sufficiently support the succinate diester compound or phthalate diester compound on the support while suppressing excessive support of the titanium halogen compound on the support.

[0083] More specifically, as a method a for producing a solid catalyst component, for example, a method can be given in which dialkoxymagnesium and a titanium halogen compound are suspended in an inert hydrocarbon solvent with a succinic acid diester compound or a phthalic acid diester compound, contacted for a predetermined time while heating, and then a titanium halogen compound is added to the resulting suspension and contacted while heating to obtain a solid product, and the solid product is washed with a hydrocarbon solvent to obtain the target solid catalyst component for olefin polymerization.

[0084] The heating temperature is preferably 70 to 150°C, more preferably 80 to 120°C, and even more preferably 90 to 110°C. The heating time is preferably 30 to 240 minutes, more preferably 60 to 180 minutes, and even more preferably 60 to 120 minutes.

[0085] There are no particular restrictions on the number of additions of the titanium halogen compound to the suspension. When the titanium halogen compound is added to the suspension in multiple portions, it is sufficient that each heating temperature falls within the aforementioned range, and the heating duration for each addition also falls within the aforementioned range.

[0086] In the above preparation method, while a succinic acid diester compound or a phthalic acid diester compound is added as an internal electron-donating compound, other internal electron-donating compounds may be further added. Furthermore, the above contact may be performed in the coexistence of, for example, other reaction reagents such as silicon, phosphorus, and aluminum, or a surfactant.

[0087] According to the present invention, there can be provided a solid catalyst component mixture for olefin polymerization that enables easy production of an olefin polymer having both high melt flowability and high rigidity.

[0088] Next, the catalyst for olefin polymerization according to the present invention will be described. The catalyst for olefin polymerization according to the present invention is (I) the solid catalyst component mixture for olefin polymerization according to the present invention, and (II) the following general formula (1) R 1 p AlQ 3-p (1) (wherein, R 1 is an alkyl group having 1 to 6 carbon atoms, Q is a hydrogen atom or a halogen atom, and p satisfies 0 < p ≦ 3), and is one or more organoaluminum compounds selected from the compounds represented by said formula characterized in that it comprises

[0089] In the catalyst for olefin polymerization according to the present invention, details of (I) the solid catalyst component mixture for olefin polymerization according to the present invention are as described above.

[0090] The catalyst for olefin polymerization according to the present invention comprises, as the organoaluminum compound, (II) one or more compounds selected from the following general formula (1); R 1 p AlQ 3-p (1) (wherein R 1 is an alkyl group having 1 to 6 carbon atoms, Q is a hydrogen atom or a halogen, p satisfies 0 < p ≦ 3, and when a plurality of R 1 are present, each R 1 may be the same as or different from each other, and when a plurality of Q are present, each Q may be the same as or different from each other.) comprises one or more selected from the compounds represented by

[0091] In the compound represented by the above general formula (1), p satisfies 0 < p ≦ 3, and specifically, p is 1, 2 or 3.

[0092] Specific examples of the organoaluminum compound represented by the above general formula (1) include trialkylaluminums such as triethylaluminum, triisopropylaluminum, tri-n-butylaluminum, tri-n-hexylaluminum and triisobutylaluminum; alkylaluminum halides such as diethylaluminum chloride and diethylaluminum bromide; and one or more selected from diethylaluminum hydride and the like. One or more selected from alkylaluminum halides such as diethylaluminum chloride and trialkylaluminums such as triethylaluminum, tri-n-butylaluminum and triisobutylaluminum are preferable, and one or more selected from triethylaluminum and triisobutylaluminum are more preferable.

[0093] The catalyst for olefin polymerization according to the present invention preferably contains (III) an external electron-donating compound.

[0094] In the catalyst for olefin polymerization according to the present invention, as (III) the external electron-donating compound, for example, the following general formula (4) R 7 r Si(NR 8 R 9) s (OR 10 ) 4-(r+s) (4) (In the formula, r is 0 or 1 to 2, s is 0 or 1 to 2, r+s is 0 or 1 to 4, R 7 , R 8 or R 9 R is a hydrogen atom or any group selected from a linear or branched alkyl group having 1 to 12 carbon atoms, a substituted or unsubstituted cycloalkyl group, a phenyl group, an allyl group, and an aralkyl group, and may contain heteroatoms, and may be the same or different from each other. 8 and R 9 They may be bonded together to form a ring shape, R 7 , R 8 and R 9 They may be the same or different. Also, R 10 A silicon compound represented by (1) is a group selected from alkyl groups, cycloalkyl groups, phenyl groups, vinyl groups, allyl groups, and aralkyl groups having 1 to 4 carbon atoms, and may contain a heteroatom.

[0095] In the silicon compound represented by the above general formula (4), R 7 This group is a hydrogen atom or any group selected from a linear or branched alkyl group having 1 to 12 carbon atoms, a substituted or unsubstituted cycloalkyl group, a phenyl group, an allyl group, and an aralkyl group, and may contain a heteroatom. R 7 Preferably, the alkyl groups are linear or branched alkyl groups having 1 to 10 carbon atoms or cycloalkyl groups having 5 to 8 carbon atoms, and particularly preferably linear or branched alkyl groups having 1 to 8 carbon atoms or cycloalkyl groups having 5 to 8 carbon atoms.

[0096] In the silicon compound represented by the above general formula (4), R 8 or R 9 This group is a hydrogen atom or any group selected from a linear or branched alkyl group having 1 to 12 carbon atoms, a substituted or unsubstituted cycloalkyl group, a phenyl group, an allyl group, and an aralkyl group, and may contain a heteroatom. R 8 or R9 Preferably, the alkyl groups are linear or branched alkyl groups having 1 to 10 carbon atoms, or cycloalkyl groups having 5 to 8 carbon atoms, and particularly preferably linear or branched alkyl groups having 1 to 8 carbon atoms, or cycloalkyl groups having 5 to 8 carbon atoms. Also, R 8 and R 9 They may be joined together to form a ring shape, in which case the ring shape is formed (NR 8 R 9 The group is preferably a perhydroquinolino group or a perhydroisoquinolino group.

[0097] In the silicon compound represented by the above general formula (4), R 7 , R 8 and R 9 They may be the same or different.

[0098] In the silicon compound represented by the above general formula (4), R 10 This group is selected from alkyl groups, cycloalkyl groups, phenyl groups, allyl groups, and aralkyl groups having 1 to 4 carbon atoms, and may contain heteroatoms. R 10 Preferably, the alkyl group is a linear or branched alkyl group having 1 to 4 carbon atoms.

[0099] In the silicon compound represented by the general formula (4) above, r is 0 or 1 to 2, and specifically, r can be 0, 1 or 2. In the silicon compound represented by the general formula (4) above, s is 0 or 1 to 2, and specifically, s can be 0, 1 or 2. In the silicon compound represented by the general formula (4) above, r+s is 0 or 1 to 4, and specifically, r+s can be 0, 1, 2, 3, or 4.

[0100] Specifically, examples of silicon compounds represented by the above general formula (4) include one or more organosilicon compounds selected from phenylalkoxysilane, alkylalkoxysilane, phenylalkylalkoxysilane, cycloalkylalkoxysilane, cycloalkylalkylalkoxysilane, (alkylamino)alkoxysilane, alkyl(alkylamino)alkoxysilane, alkyl(alkylamino)silane, alkylaminosilane, etc.

[0101] As silicon compounds in the above general formula (4) where s is 0, particularly preferred are di-n-propyldimethoxysilane, diisopropyldimethoxysilane, di-n-butyldimethoxysilane, diisobutyldimethoxysilane, di-t-butyldimethoxysilane, t-butylmethyldimethoxysilane, t-butylethyldimethoxysilane, di-n-butyldiethoxysilane, t-butyltrimethoxysilane, t-butyltriethoxysilane, dicyclohexyldimethoxysilane, dicyclohexyldiethoxysilane, cyclohexylmethyldimethoxysilane, cyclohexylmethyldiethoxysilane, and cyclohexylethyl Examples include one or more organosilicon compounds selected from dimethoxysilane, cyclohexylethyldiethoxysilane, dicyclopentyldimethoxysilane, dicyclopentyldiethoxysilane, cyclopentylmethyldimethoxysilane, cyclopentylmethyldiethoxysilane, cyclopentylethyldiethoxysilane, cyclohexylcyclopentyldimethoxysilane, cyclohexylcyclopentyldiethoxysilane, 3-methylcyclohexylcyclopentyldimethoxysilane, 4-methylcyclohexylcyclopentyldimethoxysilane, and 3,5-dimethylcyclohexylcyclopentyldimethoxysilane.

[0102] Examples of silicon compounds in which s is 1 or 2 in the above general formula (4) include one or more organosilicon compounds selected from di(alkylamino)dialkoxysilane, (alkylamino)(cycloalkylamino)dialkoxysilane, (alkylamino)(alkyl)dialkoxysilane, di(cycloalkylamino)dialkoxysilane, vinyl(alkylamino)dialkoxysilane, allyl(alkylamino)dialkoxysilane, (alkoxyamino)trialkoxysilane, (alkylamino)trialkoxysilane, (cycloalkylamino)trialkoxysilane, etc., and particularly preferably ethyl(t- Examples include butylamino)dimethoxysilane, cyclohexyl(cyclohexylamino)dimethoxysilane, ethyl(t-butylamino)dimethoxysilane, bis(cyclohexylamino)dimethoxysilane, bis(perhydroisoquinolino)dimethoxysilane, bis(perhydroquinolino)dimethoxysilane, ethyl(isoquinolino)dimethoxysilane, diethylaminotrimethoxysilane, and diethylaminotriethoxysilane, among others, and more specifically, one or more organosilicon compounds selected from bis(perhydroisoquinolino)dimethoxysilane, diethylaminotrimethoxysilane, or diethylaminotriethoxysilane.

[0103] Furthermore, two or more silicon compounds represented by the above general formula (4) may be used in combination.

[0104] The catalyst for olefin polymerization according to the present invention comprises (I) a solid catalyst component for olefin polymerization according to the present invention, (II) an organoaluminum compound represented by general formula (2), and optionally (III) an external electron-donating compound, i.e., a contact thereof. The olefin polymerization catalyst according to the present invention may be prepared by contacting (I) a solid catalyst component for olefin polymerization according to the present invention, (II) an organoaluminum compound represented by general formula (2), and optionally (III) an external electron-donating compound in the absence of olefins, or it may be prepared by contacting them in the presence of olefins (within the polymerization system), as described below.

[0105] In the olefin polymerization catalyst according to the present invention, the content ratio of each component is arbitrary as long as it does not affect the effects of the present invention and is not particularly limited. However, it is generally preferable that the mixture of (I) solid catalyst components for olefin polymerization contains 1 to 2,000 moles of (II) organoaluminum compound per mole of titanium atoms, and more preferably 50 to 1,000 moles. Furthermore, the olefin polymerization catalyst according to the present invention preferably contains 0.002 to 10,000 moles of (III) external electron-donating compound per mole of (II) organoaluminum compound, more preferably 0.010 to 2,000 moles, and even more preferably 0.010 to 0.500 moles.

[0106] According to the present invention, it is possible to provide a catalyst for olefin polymerization that can easily produce olefin polymers that have both high melt flowability and rigidity.

[0107] Next, a method for producing olefin polymers according to the present invention will be described. The method for producing olefin polymers according to the present invention is characterized by performing polymerization of olefins using the olefin polymerization catalyst according to the present invention.

[0108] In the method for producing olefin polymers according to the present invention, the polymerization of olefins may be homopolymerization or copolymerization. In the method for producing olefin polymers according to the present invention, the olefins to be polymerized can be one or more selected from ethylene, propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, vinylcyclohexane, etc., and among these, one or more selected from ethylene, propylene, and 1-butene are preferred, with propylene being more preferred. When the olefin is propylene, it may be a homopolymer of propylene, or it may be copolymerized with other α-olefins. Examples of olefins copolymerized with propylene include one or more selected from ethylene, 1-butene, 1-pentene, 4-methyl-1-pentene, vinylcyclohexane, and the like.

[0109] When the olefin polymerization catalyst according to the present invention is prepared in the presence of olefins (within the polymerization system), the ratio of each component used is arbitrary and not particularly limited, as long as it does not affect the effects of the present invention. However, it is generally preferable to contact the above-mentioned organoaluminum compound at a rate of 1 to 2000 moles per mole of titanium atoms in the above-mentioned solid catalyst component mixture for olefin polymerization, and more preferably at a rate of 50 to 1000 moles. Furthermore, it is preferable to contact an external electron-donating compound selected from the silicon compounds represented by the above-mentioned general formula (4) at a rate of 0.002 to 10.000 moles per mole of the above-mentioned organoaluminum compound, more preferably at a rate of 0.01 to 2 moles, and even more preferably at a rate of 0.010 to 0.500 moles.

[0110] The order in which the components constituting the above-mentioned olefin polymerization catalyst come into contact is arbitrary, but preferably, the above-mentioned organoaluminum compound is first charged into the polymerization system, then, if necessary, an external electron-donating compound is charged and brought into contact, and then the above-mentioned solid catalyst component mixture for olefin polymerization is charged and brought into contact. The above-mentioned solid catalyst component mixture for olefin polymerization may be prepared by mixing the first solid catalyst component for olefin polymerization and the second solid catalyst component for olefin polymerization and introducing the mixture into the polymerization system, or the first solid catalyst component for olefin polymerization and the second solid catalyst component for olefin polymerization may be introduced separately and then mixed into the polymerization system.

[0111] The method for producing olefin polymers according to the present invention may be carried out in the presence or absence of an organic solvent. Furthermore, olefin monomers such as propylene can be used in either gaseous or liquid form. The polymerization temperature is preferably 200°C or lower, more preferably 100°C or lower, and the polymerization pressure is preferably 10 MPa or lower, more preferably 5 MPa or lower. In addition, the polymerization of olefins can be carried out by either continuous polymerization or batch polymerization. Furthermore, the polymerization reaction may be carried out in one step or in two or more steps.

[0112] In addition, when polymerizing olefins using the olefin polymerization catalyst according to the present invention (also referred to as the main polymerization), it is preferable to perform prepolymerization prior to the main polymerization in order to further improve the catalytic activity, stereoregularity, and particle properties of the resulting polymer. In prepolymerization, the same olefins or monomers such as styrene as those used in the main polymerization can be used.

[0113] When performing prepolymerization, the order in which the components constituting the olefin polymerization catalyst and the monomers (olefins) are brought into contact is arbitrary, but preferably, an organoaluminum compound is first charged into a prepolymerization system set in an inert gas atmosphere or an olefin gas atmosphere, then the above-mentioned solid catalyst components for olefin polymerization are charged and brought into contact, and then olefins such as propylene are brought into contact, either alone or as a mixture of olefins such as propylene and one or more other olefins. In the above prepolymerization, when an external electron-donating compound is further charged into the prepolymerization system, it is preferable to first charge an organoaluminum compound into the prepolymerization system set to an inert gas atmosphere or an olefin gas atmosphere, then charge and contact the external electron-donating compound, and then contact the aforementioned solid catalyst component mixture for olefin polymerization, and then contact the olefin such as propylene alone, or a mixture of olefin such as propylene and one or more other olefins.

[0114] In the method for producing olefin polymers according to the present invention, the polymerization methods include slurry polymerization using an inert hydrocarbon compound solvent such as cyclohexane or heptane, bulk polymerization using a solvent such as liquefied propylene, and gas-phase polymerization using substantially no solvent, with bulk polymerization or gas-phase polymerization being preferred.

[0115] When copolymerizing propylene with monomers of other α-olefins, there are two main types: random copolymerization, in which propylene and a small amount of ethylene are used as comonomers and polymerization is carried out in one step; and so-called propylene-ethylene block copolymerization, in which propylene is homopolymerized in the first step (first polymerization tank), and copolymerization of propylene with other α-olefins such as ethylene is carried out in the second step (second polymerization tank) or in multiple steps (multi-stage polymerization tank). Block copolymerization of propylene with other α-olefins is preferred.

[0116] A block copolymer obtained by block copolymerization is a polymer containing segments in which the monomer composition of two or more monomers changes continuously. It refers to a form in which two or more polymer chains (segments) with different primary structures, such as monomer species, comonomer species, comonomer composition, comonomer content, comonomer arrangement, and stereoregularity, are linked together in a single molecular chain.

[0117] In the method for producing olefin polymers according to the present invention, the block copolymerization reaction between propylene and other α-olefins can usually be carried out by first contacting propylene alone or propylene with a small amount of α-olefin (such as ethylene) in the presence of the olefin polymerization catalyst according to the present invention, and then contacting propylene with α-olefin (such as ethylene) in the subsequent step. The polymerization reaction in the first step may be repeated multiple times, or the polymerization reaction in the subsequent step may be repeated multiple times to carry out a multi-stage reaction.

[0118] In the block copolymerization reaction between propylene and other α-olefins, it is preferable to perform polymerization in the first step by adjusting the polymerization temperature and time so that the proportion of the polypropylene portion (in the final copolymer) is 20 to 90% by mass, and then in the second step, introduce propylene and ethylene or other α-olefins so that the proportion of the rubber portion (such as ethylene-propylene rubber (EPR)) (in the final copolymer) is 10 to 80% by mass. The polymerization temperature in both the preceding and succeeding stages is preferably 200°C or less, more preferably 100°C or less, and even more preferably 65-80°C. The polymerization pressure is preferably 10 MPa or less, more preferably 6 MPa or less, and even more preferably 5 MPa or less. In the copolymerization reaction described above, either a continuous polymerization method or a batch polymerization method can be employed, and the polymerization reaction may be carried out in one step or in two or more steps. Furthermore, the polymerization time (residence time in the reactor) is preferably 1 minute to 5 hours at each polymerization stage in the preceding or succeeding stages, or even in continuous polymerization. Polymerization methods include slurry polymerization using inert hydrocarbon solvents such as cyclohexane and heptane, bulk polymerization using solvents such as liquefied propylene, and gas-phase polymerization which uses virtually no solvent. Bulk polymerization or gas-phase polymerization is preferred.

[0119] In particular, ethylene-propylene block copolymers contain EPR components (polymerization components of ethylene and propylene), and when EPR components seep onto the surface of polymer particles, the particles become sticky (adhesive) and their fluidity deteriorates. Since poor particle fluidity reduces the operability of polymer manufacturing facilities, it is desirable to select a polymer manufacturing method that can suppress the seepage of EPR components onto the particle surface.

[0120] In the olefin polymer obtained by the manufacturing method according to the present invention, the melt flow rate (MFR) indicating the melt flowability of the olefin polymer should be within a range that is high enough to maintain the excellent moldability of the olefin polymer, and should be 80 to 120 g / 10 minutes, and preferably 100 to 120 g / 10 minutes.

[0121] In this application, the melt flow rate (MFR) refers to the value measured according to ASTM D 1238 and JIS K 7210.

[0122] The olefin polymer obtained by the manufacturing method according to the present invention has a flexural modulus (FM) of 1900 MPa or more when the melt flow rate (MFR) is within a specific range (80 to 120 g / 10 mins), preferably between 1900 and 2500 MPa, and more preferably between 2000 and 2400 MPa.

[0123] In the olefin polymer obtained by the manufacturing method according to the present invention, excellent rigidity can be easily achieved because the flexural modulus (FM) is within the above range. In general, it is known that in olefin polymers obtained using a catalyst for olefin polymerization (including a solid catalyst component for olefin polymerization), melt flow rate (MFR) and flexural modulus (FM) are in a trade-off relationship. Normally, even when polypropylene with a flexural modulus (FM) of 1900 MPa or higher is produced using a solid catalyst component for olefin polymerization that contains a succinate diester compound as an internal electron-donating compound, the resulting polypropylene tends to have an extremely low melt flow rate (MFR). However, with the olefin polymer obtained by the manufacturing method according to the present invention, even when the melt flow rate (MFR) is within a specific high range of 80 to 120 g / 10 minutes, an olefin polymer with a flexural modulus (FM) of 1900 MPa or higher can be obtained.

[0124] In this application, the flexural modulus (FM) of the copolymer is defined as the value obtained by injection molding a multi-purpose test specimen type A1 as specified in JIS K7139 using NEX30III3EG manufactured by Nissei Plastic Industrial Co., Ltd., under conditions of a molding temperature of 200°C and a mold temperature of 40°C. A test specimen measuring 4.0 mm in thickness, 10.0 mm in width, and 80.0 mm in length is cut from the center of the test specimen. After conditioning the cut test specimen for 72 hours in a constant temperature room adjusted to 23°C, the value is measured at a measurement ambient temperature of 23°C according to JIS K7171 (unit: MPa).

[0125] The olefin polymers obtained by the manufacturing method according to the present invention satisfy the above-mentioned flexural modulus requirements, and therefore can easily exhibit excellent rigidity.

[0126] Furthermore, in order to maintain the excellent rigidity of the olefin polymer obtained by the manufacturing method according to the present invention, the proportion of the orientation layer (F) in the cross-section of the injection-molded article made of the olefin polymer is preferably 16.0 to 28.0%, and more preferably 18.0 to 28.0%. In this application, the orientation layer in the cross-section of an injection-molded article made of the olefin polymer refers to the surface layer (also called the skin layer) with a high degree of birefringence. The cross-section of the injection-molded article is formed with the aforementioned orientation layer and an internal non-oriented layer (also called the core layer), and these are clearly visible as distinct layers. Because the orientation layer is highly oriented, it is expected to have a high modulus of elasticity and strength, and as a result, it is thought that the more moderately thick the orientation layer, the greater the overall modulus of elasticity and strength of the molded article. On the other hand, an injection-molded article with an orientation layer that is too thin will lack sufficient modulus of elasticity and strength, and an injection-molded article with an orientation layer that is too thick will have an imbalance between the orientation layer and the non-oriented layer, making it prone to fracture in either case. In the olefin polymer obtained by the manufacturing method according to the present invention, by having the proportion (F) of the orientation layer within the above range, it is possible to easily exhibit excellent rigidity while maintaining a high flexural modulus.

[0127] In this application, the proportion of the orientation layer (F) in the cross-section of the injection-molded article made of the above-mentioned olefin polymer refers to the amount measured by the method described below. 1. Formation of molded products In accordance with JIS K 7152-1 and JIS K 6921-2, an injection-molded article having the dumbbell shape shown in Figure 1 is obtained by injection molding an olefin polymer under the following conditions. [Injection molding conditions] Equipment: NEX-III-3EG, manufactured by Nissei Plastic Industrial Co., Ltd. Specimen type: Multipurpose test specimen type A1 as described in JIS K 7139 Resin melting point: 200℃ Mold temperature: 40℃ Ejection speed: 180 mm / second Holding pressure: 50 MPa for 40 seconds 2. Preparation of measurement samples (thin sections for polarized light microscopy observation) (1) As shown in Figure 1, the obtained molded product is cut perpendicular to the resin travel direction MD at a position c1 approximately 7 cm in length MD from the gate G, and then cut perpendicular to the resin travel direction MD at a position c2 approximately 2 cm in length MD from position c1 to obtain the cut product S1 shown in Figure 2(a). (2) As shown in Figure 2(a), the cut piece S1 obtained in (1) is cut parallel to the resin propagation direction MD at its central part (position c3) to obtain the cut piece S2 shown in Figure 2(b). (3) As shown in Figure 2(b), using a rotary microtome apparatus (RX-860 manufactured by Yamato Koki Kogyo Co., Ltd.), the cut piece S2 is cut at position c4 parallel to the resin propagation direction MD to a thickness of 30 μm to obtain the thin piece-shaped measurement sample S3 shown in Figure 2(c). (4) Figure 2(d) is a schematic diagram showing the obtained flaky measurement sample S3, where the left side of Figure 2(d) is a side view of the flaky measurement sample S3 corresponding to Figure 2(c), and the right side of Figure 2(d) is a front view of the flaky measurement sample S3. 3. Polarized light microscopy observation Figure 3 is an enlarged view of the front view of the thin section of measurement sample S3 shown in the right-hand diagram of Figure 2(d). The above measurement sample S3 is observed using a polarizing microscope (EPCLIPSE LV-100NDA, manufactured by Nikon Corporation) to identify the core layer c and orientation layers h1 and h2. The thickness of the core layer is denoted as Tc, and the thicknesses of the orientation layers as Th1 and Th2. The ratio F (%) of the orientation layer to the thickness of the molded layer is calculated using the following formula (β). F(%)={(Th1+Th2) / (Th1+Tc+Th2)}×100 (β) The core layer thickness Tc and the orientation layer thicknesses Th1 and Th2 are determined by using the arithmetic mean values ​​obtained when measuring the core layer c thickness and the orientation layer thicknesses h1 and h2 at any three locations on the measurement sample S3.

[0128] According to the present invention, it is possible to provide a method for producing olefin polymers that have high melt flowability and excellent moldability, as well as even higher flexural modulus and superior rigidity. [Examples]

[0129] Next, the present invention will be described in more detail with reference to examples, but these are merely illustrative and not intended to limit the present invention.

[0130] (Performance evaluation) In the examples and comparative examples, each performance evaluation was performed according to the method described below.

[0131] <Titanium atom content> The titanium atom content was measured according to the method of JIS 8311-1997 using a solid catalyst component for olefin polymerization from which solvent components had been completely removed by preheating and vacuum drying.

[0132] <Percentage of internal electron-donating compounds> The content of internally electron-donating compounds (succinate diester compounds and phthalate diester compounds) was determined by hydrolyzing solid catalyst components for olefin polymerization, from which solvent components had been completely removed by preheating and vacuum drying. The internally electron-donating compounds were then extracted using an aromatic solvent, and this solution was measured using gas chromatography (Shimadzu Corporation, GC-14B) under the following conditions (gas chromatography FID method). The number of moles of each component was determined from the gas chromatography measurement results using a calibration curve previously measured at known concentrations. [Measurement conditions] Column: Packed column (φ2.6 × 2.1 m, Silicone SE-30 10%, Chromosorb WAW DMCS 80 / 100, manufactured by GL Sciences Co., Ltd.) Detector: FID (Flame Ionization Detector) Carrier gas: Helium, flow rate 40 mL / min Measurement temperature: Vaporization chamber 280°C, column 225°C, detector 280°C

[0133] <Polymerization activity> The polymerization activity per gram of mixed solid catalyst components was determined using the following formula (α). Polymerization activity (g / g-cat) = Mass of polymer (g) / Mass of mixed solid catalyst components (g) (α)

[0134] <Melting Flowability (MFR)> The melt flow rate (MFR) (g / 10 min), which indicates the melt flowability of the polymer, was measured in accordance with ASTM D 1238 and JIS K 7210.

[0135] <Flexural modulus (FM)> Using NEX30III3EG manufactured by Nissei Plastic Industrial Co., Ltd., injection-molded test specimens (thickness 4.0 mm, width 10.0 mm, length 80 mm) prepared under conditions of a molding temperature of 200°C and a mold temperature of 40°C were used to measure the flexural modulus (FM) of the polymer at a measurement ambient temperature of 23°C, in accordance with JIS K7171.

[0136] <Percentage of oriented layer (F) in the cross-section of an injection-molded sheet made of polymer> 1. Formation of molded products In accordance with JIS K 7152-1 and JIS K 6921-2, an injection-molded article having the dumbbell shape shown in Figure 1 was obtained by injection molding an olefin polymer under the following conditions. [Injection molding conditions] Equipment: NEX-III-3EG, manufactured by Nissei Plastic Industrial Co., Ltd. Specimen type: Multipurpose test specimen type A1 as described in JIS K 7139 Resin melting point: 200℃ Mold temperature: 40℃ Ejection speed: 180 mm / second Holding pressure: 50 MPa for 40 seconds 2. Preparation of measurement samples (thin sections for polarized light microscopy observation) (1) As shown in Figure 1, the obtained molded product was cut perpendicular to the resin travel direction MD at a position c1 approximately 7 cm in length MD from the gate G of the obtained molded product, and then cut perpendicular to the resin travel direction MD at a position c2 approximately 2 cm in length MD from position c1 to obtain the cut product S1 shown in Figure 2(a). (2) As shown in Figure 2(a), the cut piece S1 obtained in (1) was cut parallel to the resin propagation direction MD at its central part (position c3) to obtain the cut piece S2 shown in Figure 2(b). (3) As shown in Figure 2(b), using a rotary microtome apparatus (RX-860 manufactured by Yamato Koki Kogyo Co., Ltd.), the cut piece S2 was cut at position c4 parallel to the resin propagation direction MD to a thickness of 30 μm to obtain the thin piece-shaped measurement sample S3 shown in Figure 2(c). (4) Figure 2(d) is a schematic diagram showing the obtained flaky measurement sample S3, where the left side of Figure 2(d) is a side view of the flaky measurement sample S3 corresponding to Figure 2(c), and the right side of Figure 2(d) is a front view of the flaky measurement sample S3. 3. Polarized light microscopy observation Figure 3 is an enlarged view of the front view of the thin section of measurement sample S3 shown in the right-hand diagram of Figure 2(d). The above measurement sample S3 was observed using a polarizing microscope (EPCLIPSE LV-100NDA, manufactured by Nikon Corporation) to identify the core layer c and orientation layers h1 and h2. The thickness of the core layer was denoted as Tc, and the thicknesses of the orientation layers as Th1 and Th2. The ratio F (%) of the orientation layer to the thickness of the molded layer was calculated using the following formula (β). F(%)={(Th1+Th2) / (Th1+Tc+Th2)}×100 (β) The core layer thickness Tc and the orientation layer thicknesses Th1 and Th2 were determined by using the arithmetic mean values ​​obtained when measuring the core layer c thickness and orientation layer h1 and h2 thicknesses at any three locations on the sample S3.

[0137] (Manufacturing Example 1) <Synthesis of Solid Components> In a 500 mL round-bottom flask equipped with a stirrer and with the internal atmosphere replaced by nitrogen gas, 25 mL of toluene and 20 mL of titanium tetrachloride were added. In a separately prepared 300 mL round-bottom flask, 10 g of ethoxymagnesium and 30 mL of toluene were added to form a suspension. Next, the suspension was added in several portions to a 500 mL round-bottom flask. After maturation, the temperature was increased, and when it reached 60°C, 4.0 mL (3.9 g) of diethyl 2,3-diisopropylsuccinate was added, and the temperature was further increased to 110°C. The reaction was then carried out for 3 hours while stirring, maintaining a temperature of 110°C. After the reaction was complete, the mixture was washed four times with 80 mL of toluene at 100°C. Then, 15 mL of titanium tetrachloride and 45 mL of toluene were added, the temperature was raised to 100°C, and the reaction was carried out with stirring for 15 minutes. Further, 15 mL of titanium tetrachloride and 45 mL of toluene were added, the temperature was raised to 100°C, and the reaction was carried out twice with stirring for 15 minutes. After the reaction was complete, the mixture was washed six times with 75 mL of n-heptane at 60°C, and then dried under reduced pressure to obtain powdered solid component (a1) (the first solid catalyst component for olefin polymerization). In the obtained solid component (a1), the titanium content was 3.4% by mass (0.071 mol%), and the diethyl 2,3-diisopropylsuccinate (succinate diester compound) content was 18.7% by mass (0.072 mol%).

[0138] (Manufacturing example 2) <Synthesis of Solid Components> In a 500 mL round-bottom flask equipped with a stirrer and with the internal atmosphere replaced by nitrogen gas, 40 mL of toluene and 20 mL of titanium tetrachloride were added. In a separately prepared 300 mL round-bottom flask, 10 g of ethoxymagnesium and 45 mL of toluene were charged, and 2.6 mL of di-n-butyl phthalate (a phthalate diester compound) was added to form a suspension. Next, the suspension solution was added in several portions to a 500 mL round-bottom flask. After maturation, the temperature was increased, and when it reached 60°C, 1.2 mL (1.3 g) of di-n-butyl phthalate was added, and the temperature was further increased to 110°C. The reaction was then carried out for 2 hours while stirring, maintaining a liquid temperature of 110°C. After the reaction was complete, the supernatant was removed, and the mixture was washed four times with 100 mL of toluene. Then, 20 mL of titanium tetrachloride and 80 mL of toluene were added, and the mixture was allowed to react for 2 hours while maintaining a liquid temperature of 105°C. After the reaction was complete, the mixture was washed eight times with 100 mL of n-heptane, and then dried under reduced pressure to obtain a powdered solid component (b1) (a second solid catalyst component for olefin polymerization). In the obtained solid component (b1), the titanium content was 1.9% by mass (0.040 mol%), and the di-n-butyl phthalate (phthalate diester compound) content was 10.5% by mass (0.040 mol%).

[0139] (Example 1) <Preparation of mixed solid catalyst components> A charging container was prepared with nitrogen gas purged, and 2.0 mg of solid component (a1) obtained in Production Example 1 and 5.9 mg of solid component (b1) obtained in Production Example 2 were charged into it to obtain mixed solid catalyst component (A1) (mixture of solid catalyst components for olefin polymerization). The content ratios of each component in the obtained mixed solid catalyst component (A1) are shown in Tables 1 and 2.

[0140] <Formation of polymerization catalyst and polymerization reaction> A polymerization catalyst was formed by charging a 2.0-liter autoclave with a stirrer, which was purged with nitrogen gas, with 1.32 mmol of triethylaluminum, 0.26 mmol of dicyclopentylbis(ethylamino)silane (T01), and 0.0038 mmol of the mixed solid catalyst component (A1) as titanium atoms. Subsequently, 1.5 liters of hydrogen gas and 1.4 liters of liquefied propylene were added, and prepolymerization was carried out at 20°C for 5 minutes. After that, the temperature was raised, and the polymerization reaction was carried out at 70°C for 1 hour. At this time, the propylene polymerization activity (PP polymerization activity), the melt flowability (MFR) of the polymer, the flexural modulus (FM) of the polymer, and the percentage F (%) of the orientation layer in the cross-section of the injection-molded sheet made of the obtained polymer were measured per gram of solid catalyst component. The results are shown in Table 3. Furthermore, Figure 4 shows a polarized microscope image of the thin-piece measurement sample S3, which was used to measure the proportion F(%) of the orientation layer in the cross-section of the injection-molded plate made of the obtained polymer.

[0141] (Example 2) <Preparation of mixed solid catalyst components> A charging container was prepared with nitrogen gas purged, and 3.4 mg of solid component (a1) obtained in Production Example 1 and 3.4 mg of solid component (b1) obtained in Production Example 2 were charged into it to obtain mixed solid catalyst component (A2) (mixture of solid catalyst components for olefin polymerization). The content ratios of each component in the obtained mixed solid catalyst component (A2) are shown in Tables 1 and 2.

[0142] <Formation of polymerization catalyst and polymerization reaction> A polymerization catalyst was formed by charging a 2.0-liter autoclave with a stirrer, which was purged with nitrogen gas, with 1.32 mmol of triethylaluminum, 0.26 mmol of dicyclopentylbis(ethylamino)silane (T01), and 0.0038 mmol of the mixed solid catalyst component (A2) as titanium atoms. Subsequently, 1.5 liters of hydrogen gas and 1.4 liters of liquefied propylene were added, and prepolymerization was carried out at 20°C for 5 minutes. After that, the temperature was raised, and the polymerization reaction was carried out at 70°C for 1 hour. At this time, the propylene polymerization activity (PP polymerization activity), the melt flowability (MFR) of the polymer, the flexural modulus (FM) of the polymer, and the percentage F (%) of the orientation layer in the cross-section of the injection-molded sheet made of the obtained polymer were measured per gram of solid catalyst component. The results are shown in Table 3. Furthermore, Figure 5 shows a polarized microscope image of the thin-piece measurement sample S3, which was used to measure the proportion F(%) of the orientation layer in the cross-section of the injection-molded plate made of the obtained polymer.

[0143] (Example 3) <Preparation of mixed solid catalyst components> A charging container was prepared with nitrogen gas purged, and 4.5 mg of solid component (a1) obtained in Production Example 1 and 1.5 mg of solid component (b1) obtained in Production Example 2 were charged into it to obtain mixed solid catalyst component (A3) (mixture of solid catalyst components for olefin polymerization). The content ratios of each component in the obtained mixed solid catalyst component (A3) are shown in Tables 1 and 2.

[0144] <Formation of polymerization catalyst and polymerization reaction> A polymerization catalyst was formed by charging a 2.0-liter autoclave with a stirrer, which was purged with nitrogen gas, with 1.32 mmol of triethylaluminum, 0.26 mmol of dicyclopentylbis(ethylamino)silane (T01), and 0.0038 mmol of the mixed solid catalyst component (A3) as titanium atoms. Subsequently, 1.5 liters of hydrogen gas and 1.4 liters of liquefied propylene were added, and prepolymerization was carried out at 20°C for 5 minutes. After that, the temperature was raised, and the polymerization reaction was carried out at 70°C for 1 hour. At this time, the propylene polymerization activity (PP polymerization activity), the melt flowability (MFR) of the polymer, the flexural modulus (FM) of the polymer, and the percentage F (%) of the orientation layer in the cross-section of the injection-molded sheet made of the obtained polymer were measured per gram of solid catalyst component. The results are shown in Table 3. Furthermore, Figure 6 shows a polarized microscope image of the thin-piece measurement sample S3, which was used to measure the proportion F(%) of the orientation layer in the cross-section of the injection-molded plate made of the obtained polymer.

[0145] (Comparative Example 1) In Comparative Example 1, the solid component (a1) (first solid catalyst component for olefin polymerization) obtained in Production Example 1 was applied as solid catalyst component (B1) to the formation of the polymerization catalyst and polymerization reaction described later. The proportions of each component in the solid catalyst component (B1) are shown in Tables 1 and 2.

[0146] <Formation of polymerization catalyst and polymerization reaction> A polymerization catalyst was formed by charging a 2.0-liter autoclave with a stirrer, which was purged with nitrogen gas, with 1.32 mmol of triethylaluminum, 0.26 mmol of dicyclopentylbis(ethylamino)silane (T01), and 0.0038 mmol of the mixed solid catalyst component (B1) as titanium atoms. Subsequently, 1.5 liters of hydrogen gas and 1.4 liters of liquefied propylene were added, and prepolymerization was carried out at 20°C for 5 minutes. After that, the temperature was raised, and the polymerization reaction was carried out at 70°C for 1 hour. At this time, the propylene polymerization activity (PP polymerization activity), the melt flowability (MFR) of the polymer, the flexural modulus (FM) of the polymer, and the percentage F (%) of the orientation layer in the cross-section of the injection-molded sheet made of the obtained polymer were measured per gram of solid catalyst component. The results are shown in Table 3. Furthermore, Figure 7 shows a polarized microscope image of the thin-piece measurement sample S3, which was used to measure the proportion F(%) of the orientation layer in the cross-section of the injection-molded plate made of the obtained polymer.

[0147] (Comparative Example 2) In Comparative Example 2, the solid component (b1) (second solid catalyst component for olefin polymerization) obtained in Production Example 2 was applied as solid catalyst component (B2) to the formation of the polymerization catalyst and polymerization reaction described later. The proportions of each component in the solid catalyst component (B2) are shown in Tables 1 and 2.

[0148] <Formation of polymerization catalyst and polymerization reaction> A polymerization catalyst was formed by charging a 2.0-liter autoclave with a stirrer, which was purged with nitrogen gas, with 1.32 mmol of triethylaluminum, 0.26 mmol of dicyclopentylbis(ethylamino)silane (T01), and 0.0024 mmol of the mixed solid catalyst component (B2) as titanium atoms. Subsequently, 1.5 liters of hydrogen gas and 1.4 liters of liquefied propylene were added, and prepolymerization was carried out at 20°C for 5 minutes. After that, the temperature was raised, and the polymerization reaction was carried out at 70°C for 1 hour. At this time, the propylene polymerization activity (PP polymerization activity), the melt flowability (MFR) of the polymer, the flexural modulus (FM) of the polymer, and the percentage F (%) of the orientation layer in the cross-section of the injection-molded sheet made of the obtained polymer were measured per gram of solid catalyst component. The results are shown in Table 3. Furthermore, Figure 8 shows a polarized microscope image of the thin-piece measurement sample S3, which was used to measure the proportion F(%) of the orientation layer in the cross-section of the injection-molded plate made of the obtained polymer.

[0149] (Comparative Example 3) <Preparation of mixed solid catalyst components> A charging container was prepared with nitrogen gas purged, and 4.7 mg of solid component (a1) obtained in Production Example 1 and 1.2 mg of solid component (b1) obtained in Production Example 2 were charged into it to obtain mixed solid catalyst component (A3) (mixture of solid catalyst components for olefin polymerization). The content ratios of each component in the obtained mixed solid catalyst component (B3) are shown in Tables 1 and 2.

[0150] <Formation of polymerization catalyst and polymerization reaction> A polymerization catalyst was formed by charging a 2.0-liter autoclave with a stirrer, which was purged with nitrogen gas, with 1.32 mmol of triethylaluminum, 0.26 mmol of dicyclopentylbis(ethylamino)silane (T01), and 0.0038 mmol of the mixed solid catalyst component (B3) as titanium atoms. Subsequently, 1.5 liters of hydrogen gas and 1.4 liters of liquefied propylene were added, and prepolymerization was carried out at 20°C for 5 minutes. After that, the temperature was raised, and the polymerization reaction was carried out at 70°C for 1 hour. At this time, the propylene polymerization activity (PP polymerization activity), the melt flowability (MFR) of the polymer, the flexural modulus (FM) of the polymer, and the percentage F (%) of the orientation layer in the cross-section of the injection-molded sheet made of the obtained polymer were measured per gram of solid catalyst component. The results are shown in Table 3. Furthermore, Figure 9 shows a polarized microscope image of the thin-piece measurement sample S3, which was used to measure the proportion F(%) of the orientation layer in the cross-section of the injection-molded plate made of the obtained polymer. (Comparative Example 4)

[0151] <Preparation of mixed solid catalyst components> A charging container was prepared with nitrogen gas purged, and 1.6 mg of solid component (a1) obtained in Production Example 1 and 6.5 mg of solid component (b1) obtained in Production Example 2 were charged into it to obtain mixed solid catalyst component (B4) (mixture of solid catalyst components for olefin polymerization). The content ratios of each component in the obtained mixed solid catalyst component (B4) are shown in Tables 1 and 2.

[0152] <Formation of polymerization catalyst and polymerization reaction> A polymerization catalyst was formed by charging a 2.0-liter autoclave with a stirrer, which was purged with nitrogen gas, with 1.32 mmol of triethylaluminum, 0.26 mmol of dicyclopentylbis(ethylamino)silane (T01), and 0.0038 mmol of the mixed solid catalyst component (B4) as titanium atoms. Subsequently, 1.5 liters of hydrogen gas and 1.4 liters of liquefied propylene were added, and prepolymerization was carried out at 20°C for 5 minutes. After that, the temperature was raised, and the polymerization reaction was carried out at 70°C for 1 hour. At this time, the propylene polymerization activity (PP polymerization activity), the melt flowability (MFR) of the polymer, the flexural modulus (FM) of the polymer, and the proportion of the orientation layer in the cross-section of the injection-molded sheet made of the obtained polymer were measured per gram of solid catalyst component. The results are shown in Table 3. Furthermore, Figure 10 shows a polarized microscope image of the thin-piece measurement sample S3, which was used to measure the proportion F(%) of the orientation layer in the cross-section of the injection-molded plate made of the obtained polymer.

[0153] [Table 1]

[0154] [Table 2]

[0155] [Table 3]

[0156] Tables 1 and 3 show that in Examples 1 to 3, a solid catalyst mixture for olefin polymerization was prepared by preparing a first solid catalyst component for olefin polymerization containing magnesium, titanium, halogen, and succinate diester compound, and a second solid catalyst component for olefin polymerization containing magnesium, titanium, halogen, and phthalate diester compound, in a mass ratio of first solid catalyst component for olefin polymerization:second solid catalyst component for olefin polymerization = 37:63 to 87:13. By using this mixture for the polymerization of olefins, it can be seen that olefin polymers with high melt flowability (MFR) of 80 to 120 g / 10 min, excellent moldability, and high flexural modulus (FM) of 1900 MPa or higher, as well as excellent rigidity, can be easily produced. This is thought to be because, by applying a mixture containing a first solid catalyst component for olefin polymerization and a second solid catalyst component for olefin polymerization in predetermined proportions to the polymerization of olefins, the first solid catalyst component for olefin polymerization produces a first olefin polymer with a high flexural modulus and a broad molecular weight distribution, and this first olefin polymer with a broad molecular weight distribution exhibits high compatibility with the second olefin polymer produced by the second solid catalyst component for olefin polymerization. In fact, as shown in the proportion F of the blended layers in Figures 4 to 6 and Table 3, it can be seen that when olefins are polymerized using the solid catalyst component mixture for olefin polymerization obtained in Examples 1 to 3, high melt flowability can be achieved in the resulting olefin polymer without significantly changing the proportion of the orientation layer (Th1 and Th2) that affects the flexural modulus.

[0157] On the other hand, as can be seen from Tables 1 and 3, in Comparative Examples 1 and 2, since only one of either a solid catalyst component for olefin polymerization containing magnesium, titanium, halogen, and succinate diester compound, or a solid catalyst component for olefin polymerization containing magnesium, titanium, halogen, and phthalate diester compound was used, only olefin polymers with poor moldability were obtained, resulting in a low melt flow rate (MFR) of 56 g / 10 min (Comparative Example 1), and when used for olefin polymerization, only olefin polymers with poor rigidity were obtained, resulting in a low flexural modulus (FM) of 1720 MPa (Comparative Example 2).

[0158] Furthermore, as can be seen from Tables 1 and 3, in Comparative Examples 3 and 4, a solid catalyst mixture for olefin polymerization was prepared in which the mixing ratio of the first solid catalyst component for olefin polymerization and the second solid catalyst component for olefin polymerization was outside the predetermined range, and this was used for the polymerization of olefins. As a result, only olefin polymers with poor moldability were obtained, with a low melt flow rate (MFR) of 78 g / 10 min (Comparative Example 3), and when used for the polymerization of olefins, only olefin polymers with poor rigidity were obtained, with a low flexural modulus (FM) of 1780 MPa (Comparative Example 4). [Industrial applicability]

[0159] According to the present invention, it is possible to provide a solid catalyst component mixture for olefin polymerization that can easily produce olefin polymers that have both high melt flowability and rigidity, as well as a catalyst for olefin polymerization and a method for producing olefin polymers.

Claims

1. A first solid catalyst component for olefin polymerization comprising magnesium, titanium, halogen, and succinate diester compounds, A second solid catalyst component for olefin polymerization containing magnesium, titanium, halogen, and phthalate diester compounds, The mixture is included in such a mass ratio that the first solid catalyst component for olefin polymerization and the second solid catalyst component for olefin polymerization are 37:63 to 87:

13. A mixture of solid catalyst components for olefin polymerization, characterized by the above.

2. The solid catalyst component mixture for olefin polymerization according to claim 1, wherein the content of the succinate diester compound is 4.7 to 14.9% by mass on a solid content basis.

3. The solid catalyst component mixture for olefin polymerization according to claim 1, wherein the content of the phthalate diester compound is 2.2 to 7.9% by mass on a solid content basis.

4. (I) The solid catalyst component mixture for olefin polymerization described in claim 1 and (II) General formula (1) R １ ｐ AlQ ３－ｐ (1) (In the formula, R １ Q is an alkyl group having 1 to 6 carbon atoms, Q is a hydrogen atom or a halogen atom, p is 0 < p ≤ 3, and R １ If multiple R １ Q can be the same or different from each other, and if there are multiple Qs, each Q can be the same or different from each other. One or more organoaluminum compounds selected from the compounds represented by A catalyst for olefin polymerization, characterized by containing the following:

5. (I) The solid catalyst component mixture for olefin polymerization according to claim 1, (II) General formula (1) R １ ｐ AlQ ３－ｐ (1) (In the formula, R １ Q is an alkyl group having 1 to 6 carbon atoms, Q is a hydrogen atom or a halogen atom, p is 0 < p ≤ 3, and R １ If multiple R １ Q can be the same or different from each other, and if there are multiple Qs, each Q can be the same or different from each other. One or more organoaluminum compounds selected from the compounds represented by and (III) External electron-donating compounds A catalyst for polymerization of olefins according to claim 4, comprising:

6. A method for producing an olefin polymer, characterized by polymerizing olefins using the olefin polymerization catalyst described in claim 4 or claim 5.

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