Propylene monopolymer

Abstract

The present invention provides a catalyst for olefin polymerization that, despite containing a solid catalyst component for olefin polymerization that includes compounds other than phthalates as internal electron-donating compounds, can easily produce propylene homopolymers with excellent melt flowability and moldability, as well as even better flexural modulus. [Solution] A catalyst for olefin polymerization is characterized by comprising a solid catalyst component for olefin polymerization containing magnesium, titanium, halogen, and succinate diester compound, wherein the ratio (S / T) of the total content (S) of the internal electron-donating compound mainly composed of the succinate diester compound to the titanium content (T) is 0.60 to 1.30 in molar ratio, an organoaluminum compound, and one or more external electron-donating compounds selected from specific aminosilane compounds.

Description

[Technical Field]

[0001] This invention relates to a catalyst for olefin polymerization, a method for producing olefin polymers, and a propylene homopolymer. [Background technology]

[0002] In recent years, olefin polymers such as polypropylene (PP) have been used in a variety of applications, including molded products such as automotive parts and home appliances, as well as containers and films.

[0003] Polypropylene resin compositions are lightweight, highly moldable, and possess excellent chemical stability, including heat resistance and chemical resistance of molded articles. Furthermore, they offer excellent cost performance, making them one of the most important plastic materials used in many fields.

[0004] To further expand its applications, there is a growing demand for polypropylene that can be used as a substitute for polystyrene and ABS resin, possessing high melt flow rate (MFR), excellent moldability, and superior flexural modulus (FM).

[0005] In the polymerization of olefins such as propylene, polymerization methods using solid catalyst components containing magnesium atoms, titanium atoms, halogen atoms, and internally electron-donating compounds as essential components are known, and numerous methods have been proposed for polymerizing or copolymerizing olefins in the presence of a catalyst for olefin polymerization consisting of the above-mentioned solid catalyst component, organoaluminum compounds, and organosilicon compounds (see Patent Document 1, etc.).

[0006] For example, Patent Document 1 proposes a method for polymerizing propylene using an olefin polymerization catalyst that includes a solid titanium catalyst component on which an internally electron-donating compound such as a phthalate ester is supported, an organoaluminum compound as a co-catalyst component, and an organosilicon compound having at least one Si-OC bond. Many documents, including Patent Document 1, have proposed methods for obtaining highly stereoregular polymers with high polymerization activity by using phthalate esters as the internally electron-donating compound. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 57-63310 [Patent Document 2] Japanese Patent Publication No. 2000-017019 [Overview of the project] [Problems that the invention aims to solve]

[0008] However, di-n-butyl phthalate and benzyl butyl phthalate, which are types of phthalate esters, have been identified as Substance of Very High Concern (SVHC) substances under the European Registration, Evaluation, Authorization and Restriction of Chemicals (REACH) regulations. From the perspective of reducing environmental impact, there is a growing demand to switch to catalyst systems that do not use SVHC substances.

[0009] On the other hand, when a solid catalyst component for olefin polymerization containing compounds other than phthalate esters as the internal electron-donating compound is used, it is known that the polymers obtained when subjected to olefin polymerization have inferior properties compared to when a solid catalyst component for olefin polymerization containing phthalate esters as the internal electron-donating compound is used. In particular, it becomes difficult to produce polymers with excellent melt flowability and moldability, and excellent flexural modulus.

[0010] To improve moldability, polymers with moderate melt flow properties (MFR) and excellent linear viscoelasticity exhibiting high complex viscosity at low angular frequencies and low complex viscosity at high angular frequencies are preferred. As such polymers, for example, polymers with a broad molecular weight distribution are known to be suitable.

[0011] As a method to broaden the molecular weight distribution and obtain polypropylene with good moldability, for example, Patent Document 2 proposes a method of multi-stage polymerization using multiple polymerization reactors. However, the polymerization method described in Patent Document 2 discloses an example of using a solid catalyst component for olefin polymerization that contains a phthalate ester as an internal electron-donating compound, and there is a growing demand for polymers that exhibit even better flexural modulus (FM) as a result.

[0012] Thus, conventionally, no catalyst for olefin polymerization was known that could produce polypropylene (propylene homopolymer) with a melt flow rate (MFR) of 300 g / 10 min or less, which is an indicator of moldability and is practically suitable for use, as well as a high complex viscoelastic ratio of 5.5 or more and a high flexural modulus (FM) of 1900 MPa or more.

[0013] Under these circumstances, the present invention aims to provide a catalyst for olefin polymerization that, despite containing a solid catalyst component for olefin polymerization that includes compounds other than phthalates as internal electron-donating compounds, can easily produce propylene homopolymers that are excellent in melt flowability and moldability, as well as having even better flexural modulus, and also to provide a method for producing olefin polymers and a propylene homopolymer. [Means for solving the problem]

[0014] As a result of intensive studies by the present inventors to solve the above technical problems, an olefin polymerization solid catalyst component containing magnesium, titanium, a halogen, and a succinic acid diester compound, wherein the ratio (S / T) represented by the total content (S) of the internal electron donor compound mainly composed of the succinic acid diester compound to the content (T) of titanium is 0.60 to 1.30 in molar ratio, an organoaluminum compound, and one or more external electron donor compounds selected from specific aminosilane compounds, it has been found that the above technical problems can be solved, and the present invention has been completed based on this finding.

[0015] That is, the present invention provides (1) an olefin polymerization solid catalyst component containing magnesium, titanium, a halogen, and a succinic acid diester compound, wherein the ratio (S / T) represented by the total content (S) of the internal electron donor compound mainly composed of the succinic acid diester compound to the content (T) of titanium is 0.60 to 1.30 in molar ratio, an organoaluminum compound, the following general formula (I); R 1 n Si(NR 2 R 3 ) 4-n (I) (In the formula, R 1 represents an alkyl group having 1 to 20 carbon atoms, a vinyl group, an alkenyl group having 3 to 12 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a vinyloxy group, an alkenyloxy group having 3 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, a cycloalkyloxy group having 3 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aryloxy group having 6 to 20 carbon atoms. When there are a plurality of R 1 , the plurality of R 1 may be the same as or different from each other. R 2 and R 3 represent a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, a vinyl group, an alkenyl group having 3 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, a cycloalkenyl group having 3 to 20 carbon atoms, or an aryl group having 6 to 20 carbon atoms. R 2 and R 3They may be identical or different from each other, and they may also be joined together to form a ring, NR 2 R 3 If multiple bases exist, multiple NRs 2 R 3 The bases may be identical or different. n is 1 ≤ n ≤ 3. One or more external electron-donating compounds selected from aminosilane compounds represented by and A catalyst for olefin polymerization, characterized by containing the following: (2) The olefin polymerization catalyst according to (1) above, wherein the total content (S) of the internal electron-donating compound mainly composed of the succinate diester compound in the solid catalyst component for olefin polymerization is 10.0% by mass or more. (3) The catalyst for polymerization of olefins according to (1) or (2) above, wherein the titanium content (T) in the solid catalyst component for polymerization of olefins is 1.0 to 6.0% by mass. (4) The succinate diester compound is of the following general formula (II); [ka] (In the formula, R 4 and R 5 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. 6 and R 7 (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 olefin polymerization catalysts selected from the compounds represented by (1) to (3) above, (5) The organoaluminum compound is the following general formula (III); R 8 p AlQ 3-p (III) (In the formula, R 8 Q is an alkyl group having 1 to 6 carbon atoms, Q is a hydrogen atom or a halogen, and p is 0 <p≦3であり、R 8 If there are multiple R 8Q 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 olefin polymerization catalysts selected from the compounds represented by (1) to (4) above, (6) A method for producing an olefin polymer, characterized by polymerizing olefins using an olefin polymerization catalyst described in any of (1) to (5) above, and (7)(a) Melt flow rate is 300g / 10 minutes or less, (b) Flexural modulus of 1900 MPa or more, (c) The ratio of the complex viscosity η* at an angular frequency of 0.01 radians / second to the complex viscosity η* at an angular frequency of 100 radians / second is 5.5 or greater. Propylene monoprocess characterized by This provides... [Effects of the Invention]

[0016] According to the present invention, despite containing a solid catalyst component for olefin polymerization that includes compounds other than phthalate esters as internal electron-donating compounds, it is possible to easily produce a propylene homopolymer that is excellent in melt flowability and moldability, as well as having an even better flexural modulus. Furthermore, the present invention provides a method for producing olefin polymers and a propylene homopolymer. [Modes for carrying out the invention]

[0017] First, the catalyst for olefin polymerization according to the present invention will be described. The olefin polymerization catalyst according to the present invention comprises magnesium, titanium, halogen, and succinate diester compound, wherein the ratio (S / T) of the total content (S) of the internal electron-donating compound mainly composed of the succinate diester compound to the titanium content (T) is 0.60 to 1.30 in molar ratio, and Organoaluminum compounds and, The following general formula (I); R1 n Si(NR 2 R 3 ) 4-n (I) (In the formula, R 1 This represents an alkyl group having 1 to 20 carbon atoms, a vinyl group, an alkenyl group having 3 to 12 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a vinyloxy group, an alkenyloxy group having 3 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, a cycloalkyloxy group having 3 to 20 carbon atoms, or an aryl group having 6 to 20 carbon atoms, or an aryloxy group having 6 to 20 carbon atoms. 1 If multiple R 1 They may be the same or different from each other. 2 and R 3 R represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, a vinyl group, an alkenyl group having 3 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, a cycloalkenyl group having 3 to 20 carbon atoms, or an aryl group having 6 to 20 carbon atoms. 2 and R 3 They may be identical or different from each other, and they may also be joined together to form a ring, NR 2 R 3 If multiple bases exist, multiple NRs 2 R 3 The bases may be identical or different. n is 1 ≤ n ≤ 3. One or more external electron-donating compounds selected from aminosilane compounds represented by and It is characterized by containing the following.

[0018] Examples of solid catalyst components for olefin polymerization that constitute the olefin polymerization catalyst according to the present invention include 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, examples include a catalytic reaction product obtained by bringing a magnesium compound and a tetravalent titanium halogen compound into contact with these raw materials and an internally electron-donating compound containing a succinic acid diester compound.

[0019] 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.

[0020] 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.

[0021] The above-mentioned dialkoxymagnesium is preferably in granular or powder form, and may be of an irregular shape or spherical.

[0022] 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.

[0023] The spherical dialkoxymagnesium mentioned above does not necessarily have to be perfectly spherical; elliptical or potato-shaped forms can also be used.

[0024] 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.

[0025] 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.

[0026] 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.

[0027] In the solid catalyst component for olefin polymerization according to the present invention, the magnesium compound has a specific surface area of ​​5 m². 2Preferably, 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.

[0028] 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.

[0029] The above magnesium compound is preferably in solution or suspension form during the reaction, as this allows the reaction to proceed smoothly.

[0030] 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.

[0031] 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.

[0032] In the solid catalyst component for olefin polymerization that constitutes the olefin polymerization catalyst 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 (IV) Ti(OR 9 ) r X 4-r (IV) (In the formula, R 9 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).

[0033] In the general formula (IV) above, r is 0 ≤ r ≤ 3, and specifically, r can be 0, 1, 2, or 3.

[0034] Examples of titanium halides represented by the above general formula (IV) include one or more titanium tetrahalides selected from titanium tetrachloride, titanium tetrabromide, titanium tetraiodide, etc. Furthermore, examples of alkoxy titanium halides represented by the above general formula (IV) include 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.

[0035] In the solid catalyst component for olefin polymerization that constitutes the olefin polymerization catalyst according to the present invention, the succinate diester compound is the following general formula (II); [ka] (In the formula, R 4 and R 5 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. 6 and R 7 (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].

[0036] In the compound represented by the above general formula (II), R 4 and R 5 These are hydrogen atoms or alkyl groups having 1 to 4 carbon atoms, and may be the same or different from each other. R 4 or R 5 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 (II), R 6 and R 7 These are linear alkyl groups or branched alkyl groups having 2 to 4 carbon atoms, and may be the same or different from each other. R 6 and R 7 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.

[0037] In the solid catalyst component for olefin polymerization that constitutes the olefin polymerization catalyst according to the present invention, the succinate diester compound is not particularly limited as long as it is a dialkyl succinate represented by the general formula (II), 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.

[0038] The solid catalyst component for olefin polymerization that constitutes the olefin polymerization catalyst according to the present invention contains a succinate 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).

[0039] 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.

[0040] 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.

[0041] On the other hand, the solid catalyst component for olefin polymerization that constitutes the olefin polymerization catalyst according to the present invention is preferably such that the phthalate ester content 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 phthalate ester-free (below the detection limit)).

[0042] The solid catalyst component for olefin polymerization that constitutes the olefin polymerization catalyst according to the present invention contains a succinate diester compound along with other internally electron-donating compounds. This allows for easy control of the hydrogen responsiveness during polymerization, as well as the properties of the resulting olefin polymer, such as stereoregularity and molecular weight distribution, to a range equivalent to that of polymers produced using conventional solid catalysts containing phthalate esters as internally electron-donating compounds.

[0043] The solid catalyst component for olefin polymerization that constitutes the olefin polymerization catalyst according to the present invention preferably contains a succinate diester compound of 7.0% by mass or more, more preferably 15.0 to 25.0% by mass, and even more preferably 20.0 to 23.0% by mass, when calculated on a solid content basis.

[0044] The solid catalyst component for olefin polymerization that constitutes the olefin polymerization catalyst according to the present invention has a succinate diester compound content of 7.0% by mass or more when calculated on a solid content basis. As a result, when subjected to the polymerization of olefins, it is possible to easily produce a propylene homopolymer with excellent melt flow properties and even better flexural modulus.

[0045] As described above, the solid catalyst component for olefin polymerization constituting the olefin polymerization catalyst according to the present invention may contain other internal electron-donating compounds, mainly consisting of a succinate diester compound, as an internal electron-donating compound. The total content (S) of the internal electron-donating compound mainly consisting of a succinate diester compound is preferably 10.0% by mass or more, more preferably 15.0 to 25.0% by mass, and even more preferably 20.0 to 24.0% by mass.

[0046] In this application, "primarily composed of succinate diester compounds" means that the succinate diester compound accounts for 60.0 to 100.0% by mass of the total internal electron-donating compounds constituting the solid catalyst component for olefin polymerization.

[0047] In the olefin polymerization catalyst according to the present invention, the ratio (S / T) of the total content (S) of the internal electron-donating compound, mainly composed of a succinate diester compound, to the titanium content (T) in the solid catalyst component for olefin polymerization is preferably 0.60 to 1.30, more preferably 0.60 to 1.20, and more preferably 0.65 to 1.20 in molar ratio.

[0048] The solid catalyst component for olefin polymerization according to the present invention has a ratio (S / T) of the content of the succinic acid diester compound (S) to the content of titanium (T), that is, the ratio of the total content of the internal electron-donating compound mainly composed of the succinic acid diester compound in the solid catalyst component for olefin polymerization according to the present invention to the content of titanium is 0.60 to 1.30 in molar ratio. This allows for the more effective production of propylene homopolymers with excellent melt flow properties and flexural modulus when subjected to olefin polymerization.

[0049] Conventionally, succinate diester compounds were considered expensive and difficult to use as internal electron-donating compounds in solid catalyst components for olefin polymerization, and were thought to be compounds that did not easily improve the stereoregularity of the resulting olefin polymers when subjected to olefin polymerization. For this reason, they had not been adopted as internal electron-donating compounds in solid catalyst components for olefin polymerization, nor had they been included in large quantities. However, the inventors' research revealed, quite unexpectedly, that by setting the ratio of the total content of internal electron-donating compounds, mainly succinate diester compounds, to the titanium content in the solid catalyst component for olefin polymerization to 0.60 to 1.30 in molar terms, and including a high proportion of succinate diester compounds, it is possible to produce propylene homopolymers with a higher flexural modulus than conventional ones while ensuring practically useful melt flowability when subjected to olefin polymerization. This discovery led to the completion of the present invention.

[0050] The solid catalyst component for olefin polymerization that constitutes the catalyst 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.

[0051] In the present invention, the solid catalyst component for olefin polymerization that constitutes the catalyst 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 linear, partially hydrogenated, cyclic, or modified polysiloxane with a length of 3 to 500 centistokes at room temperature, which is liquid or viscous at room temperature.

[0052] 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.

[0053] The solid catalyst component for olefin polymerization that constitutes the olefin polymerization catalyst according to the present invention is preferably prepared by bringing the above-mentioned dialkoxymagnesium, titanium halogen compound, and succinate diester compound into contact with each other in the presence of an inert organic solvent, as may be further necessary with other components.

[0054] 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.

[0055] As a method for producing the solid catalyst component for olefin polymerization that constitutes the olefin polymerization catalyst according to the present invention, when preparing the solid catalyst component for olefin polymerization according to the present invention by contacting dialkoxymagnesium, a titanium halogen compound, and a succinate diester compound with each other, The titanium halogen compound is brought into contact with dialkoxymagnesium multiple times, and when the titanium halogen compound is brought into contact with dialkoxymagnesium for the first time, 1.5 to 10.0 moles of the titanium halogen compound are used per mole of dialkoxymagnesium. The total amount of titanium compound used is 5.0 to 18.0 moles per mole of dialkoxymagnesium. Furthermore, there is a method for obtaining a target solid catalyst component for olefin polymerization by using the succinate diester compound in an amount of 0.10 to 0.20 moles per mole of dialkoxymagnesium (hereinafter referred to as method a for producing the solid catalyst component).

[0056] 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.

[0057] 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.

[0058] 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.

[0059] 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.

[0060] In method a for producing the solid catalyst component, it is preferable to use 0.10 to 0.20 moles of the succinate diester compound per mole of dialkoxymagnesium, 0.10 to 0.18 moles of the succinate diester compound per mole of dialkoxymagnesium, and more preferably 0.10 to 0.15 moles of the succinate diester compound per mole of dialkoxymagnesium.

[0061] In method a for producing the solid catalyst component, by controlling the amount of succinate diester compound used per mole of dialkoxymagnesium within the above range, it is possible to sufficiently support the succinate diester compound while suppressing excessive support of the titanium halogen compound on the support.

[0062] More specifically, as a method a for producing a solid catalyst component, for example, a method can be given in which dialkoxymagnesium, a titanium halogen compound, and a succinic acid diester compound are suspended in an inert hydrocarbon solvent, 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.

[0063] 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.

[0064] There are no particular restrictions on the number of times the titanium halogen compound can be added to the above suspension. When titanium halogen compounds are added to the above suspension multiple times, the heating temperature for each addition should be within the above range, and the heating time for each addition should be within the above range.

[0065] In addition, other internally electron-donating compounds may be used in combination with the succinic acid diester compound in the above preparation method. Furthermore, the above contact may be carried out in the presence of other reaction reagents or surfactants, such as silicon, phosphorus, or aluminum.

[0066] In the solid catalyst component for olefin polymerization that constitutes the olefin polymerization catalyst according to the present invention, magnesium, titanium, halogen, and succinate diester compound can each be included in desired amounts, provided that the content of the succinate diester compound and the molar ratio expressed as the content of the succinate diester compound (molar amount) / titanium (molar amount) satisfy the above-mentioned requirements.

[0067] The solid catalyst component for olefin polymerization that constitutes the olefin polymerization catalyst according to the present invention preferably contains titanium in an atomic weight 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. The solid catalyst component for olefin polymerization that constitutes the olefin polymerization catalyst 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 solid catalyst component for olefin polymerization that constitutes the olefin polymerization catalyst according to the present invention preferably contains halogen in an amount of 50.0 to 70.0% by mass on an atomic weight basis, more preferably 55.0 to 68.0% by mass, even more preferably 58.0 to 67.0% by mass, and even more preferably 60.0 to 66.0% by mass.

[0068] In this application, the titanium content in the solid catalyst component for olefin polymerization refers to the value measured in accordance with the method (redox titration) described in JIS 8311-1997 "Method for Determining Titanium in Titanium Ore".

[0069] Furthermore, in this application, the magnesium 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 is dissolved in hydrochloric acid solution and titrated with EDTA solution.

[0070] Furthermore, in this application, the halogen content in the solid catalyst component for olefin polymerization refers to the value measured by a silver nitrate titration method, in which the solid catalyst component is treated with a mixed solution of sulfuric acid and pure water to make an aqueous solution, a predetermined amount is taken, and the halogen is titrated with a silver nitrate standard solution.

[0071] Furthermore, in this application, the content of succinate diester compounds, other internally electron-donating compounds added as needed, and phthalate esters contained in the solid catalyst component for olefin polymerization refer to values ​​obtained by hydrolyzing the solid catalyst component for olefin polymerization, extracting succinate diester compounds, other internally electron-donating compounds added as needed, and phthalate esters using an aromatic solvent, and measuring this solution by gas chromatography FID (Flame Ionization Detector).

[0072] The solid catalyst component for olefin polymerization that constitutes the olefin polymerization catalyst according to the present invention has a total pore volume of 0.3 to 1.0 cm² with a diameter of 1 μm or less, as measured by the mercury intrusion method. 3 Preferably, the weight is / g, and the size is 0.3-0.8cm. 3 It is more preferable that the value is / g, and the size is 0.3-0.6cm. 3 A value of / g is even more preferable.

[0073] The solid catalyst component for olefin polymerization that constitutes the olefin polymerization catalyst according to the present invention has a total pore volume of 1 μm or less in diameter, as measured by the mercury intrusion method, within the above range. Therefore, when subjected to block copolymerization of olefins, it is possible to sufficiently retain rubber components that cause stickiness within the particles, and a block copolymer with excellent fluidity (low stickiness) can be obtained.

[0074] In this application, the total pore volume of 1 μm or less in diameter, measured by the mercury intrusion method, refers to the value measured using a mercury intrusion porosimeter (Micromertics, Autopore III 9420).

[0075] The solid catalyst component for olefin polymerization that constitutes the olefin polymerization catalyst according to the present invention has a specific surface area of ​​200 m². 2 It is preferable that the amount is 300-500m or more / g. 2 It is preferable that the amount is 350-500m or more. 2 It is more preferable if the amount is 1 / g or more.

[0076] The solid catalyst component for olefin polymerization that constitutes the olefin polymerization catalyst according to the present invention has a specific surface area of ​​200 m². 2 By having a concentration of 1 / g or higher, when subjected to polymerization of olefins, particularly copolymerization of olefins, the olefins enter into pores formed on the surface of the solid catalyst component and undergo the polymerization reaction within these pores. This allows for the preparation of olefin polymers under high polymerization activity, while suppressing the stickiness of the solid catalyst component surface associated with copolymer formation, and enabling the polymerization reaction to be carried out easily with high operability.

[0077] In this application, the specific surface area of ​​the solid catalyst component for olefin polymerization refers to the value automatically measured using a specific surface area analyzer (QUANTA SORBQS-17, manufactured by QUANTA CHROME) by the BET method.

[0078] The catalyst for olefin polymerization according to the present invention contains an organoaluminum compound. In the catalyst for olefin polymerization according to the present invention, the organoaluminum compound is the following general formula (III); R 8 p AlQ 3-p (III) (In the formula, R 8 Q is an alkyl group having 1 to 6 carbon atoms, Q is a hydrogen atom or a halogen, and p is 0 <p≦3であり、R 8 If there are multiple R 8 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. It is preferably at least one selected from the compounds represented by

[0079] In the compound represented by the general formula (III) above, p satisfies 0 < p ≤ 3, and specifically, examples of p include 1, 2, or 3.

[0080] Specific examples of the organoaluminum compound represented by the general formula (III) above include one or more selected from trialkylaluminums such as triethylaluminum, triisopropylaluminum, tri-n-butylaluminum, tri-n-hexylaluminum, triisobutylaluminum, etc., alkylaluminum halides such as diethylaluminum chloride, diethylaluminum bromide, etc., and diethylaluminum hydride, etc. One or more selected from alkylaluminum halides such as diethylaluminum chloride, trialkylaluminums such as triethylaluminum, tri-n-butylaluminum, triisobutylaluminum, etc. are preferred, and one or more selected from triethylaluminum and triisobutylaluminum are more preferred.

[0081] The catalyst for olefin polymerization of the present invention is represented by the following general formula (I); R 1 n Si(NR 2 R 3 ) 4-n (I) (In the formula, R 1 represents an alkyl group having 1 to 20 carbon atoms, a vinyl group, an alkenyl group having 3 to 12 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a vinyloxy group, an alkenyloxy group having 3 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, a cycloalkyloxy group having 3 to 20 carbon atoms, or an aryl group having 6 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms. When there are a plurality of R 1 , the plurality of R 1 may be the same as or different from each other. R 2 and R 3represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, a vinyl group, an alkenyl group having 3 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, a cycloalkenyl group having 3 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, R 2 and R 3 may be the same as or different from each other, and may also be bonded to each other to form a ring. When there are a plurality of NR 2 R 3 groups, the plurality of NR 2 R 3 groups may be the same as or different from each other. n satisfies 1 ≦ n ≦ 3.) It contains one or more external electron donating compounds selected from amino silane compounds represented by

[0082] In the compound represented by the above general formula (I), R 1 represents an alkyl group having 1 to 20 carbon atoms, a vinyl group, an alkenyl group having 3 to 12 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a vinyloxy group, an alkenyloxy group having 3 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, a cycloalkyloxy group having 3 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms. When there are a plurality of R 1 the plurality of R 1 may be the same as or different from each other. As R 1 an alkyl group having 1 to 8 carbon atoms or a cycloalkyl group having 5 to 8 carbon atoms is preferable, and an alkyl group having 1 to 6 carbon atoms and a cycloalkyl group having 5 to 6 carbon atoms are more preferable.

[0083] In the amino silane compound represented by the above general formula (I), n satisfies 1 ≦ n ≦ 3. Specifically, examples of n include 1, 2 or 3.

[0084] Examples of the amino silane compound represented by the above general formula (I) include alkyltris(alkylamino)silane, dialkylbis(alkylamino)silane, trialkyl(alkylamino)silane and the like.

[0085] Specifically, the aminosilane compound represented by the above general formula (I) can be one or more selected from bis(ethylamino)methylethylsilane, t-butylmethylbis(ethylamino)silane, cyclohexylmethylbis(ethylamino)silane, dicyclohexylbis(ethylamino)silane, dicyclopentylbis(ethylamino)silane, bis(methylamino)(methylcyclopentylamino)methylsilane, etc. The aminosilane compound represented by the above general formula (I) is preferably one or more selected from t-butylmethylbis(ethylamino)silane, cyclohexylmethylbis(ethylamino)silane, dicyclohexylbis(ethylamino)silane, dicyclopentylbis(ethylamino)silane, etc.

[0086] The aminosilane compounds represented by the above general formula (I) may be used in combination of two or more types.

[0087] The catalyst for olefin polymerization according to the present invention contains the above-mentioned solid catalyst component for olefin polymerization and an organoaluminum compound, as well as one or more external electron-donating compounds selected from the aminosilane compounds represented by the above general formula (I). As a result, it is possible to easily produce olefin polymers with a high complex viscoelastic ratio, excellent moldability, and even better flexural modulus.

[0088] The catalyst for olefin polymerization according to the present invention comprises the above-mentioned solid catalyst component for olefin polymerization, an organoaluminum compound, and one or more external electron-donating compounds selected from the above-mentioned aminosilane compounds represented by general formula (I), i.e., a contact thereof. The olefin polymerization catalyst according to the present invention may be prepared by contacting the above-mentioned solid catalyst component for olefin polymerization, an organoaluminum compound, and one or more external electron-donating compounds selected from the above-mentioned aminosilane compounds represented by general formula (I) 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.

[0089] In the olefin polymerization catalyst according to the present invention, the content ratio of each component is arbitrary and not particularly limited as long as it does not affect the effects of the present invention. However, it is generally preferable that the solid catalyst component for olefin polymerization contains 1 to 2000 moles of organoaluminum compound per mole of titanium atoms, and more preferably 50 to 1000 moles. Furthermore, the olefin polymerization catalyst according to the present invention preferably contains 0.002 to 10 moles, more preferably 0.01 to 2 moles, and even more preferably 0.01 to 0.5 moles of the external electron-donating compound represented by the above general formula (I) per mole of organoaluminum compound.

[0090] According to the present invention, despite containing a solid catalyst component for olefin polymerization that includes compounds other than phthalates as internal electron-donating compounds, it is possible to easily produce a propylene homopolymer that is excellent in melt flowability and moldability, as well as having an even better flexural modulus.

[0091] 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.

[0092] 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 above olefin is propylene, it may be a homopolymerization of propylene, or it may be copolymerization 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.

[0093] 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 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 aminosilane compounds represented by the above-mentioned general formula (I) 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.

[0094] The order in which the components constituting the above-mentioned olefin polymerization catalyst come into contact is arbitrary, but it is preferable to first charge the above-mentioned organoaluminum compound into the polymerization system, then charge and contact an external electron-donating compound selected from the aminosilane compounds represented by the above-mentioned general formula (I), and then charge and contact the above-mentioned solid catalyst component for olefin polymerization.

[0095] 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.

[0096] 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.

[0097] 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 externally electron-donating compound selected from the aminosilane compounds represented by the general formula (I) 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 externally electron-donating compound selected from the aminosilane compounds represented by the general formula (I), and then contact the system with the above-mentioned solid catalyst component for olefin polymerization, followed by contact with olefins such as propylene alone, or with a mixture of olefins such as propylene and one or more other olefins.

[0098] 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.

[0099] 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.

[0100] 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.

[0101] 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.

[0102] The block copolymerization reaction of propylene and other α-olefins is specifically carried out by adjusting the polymerization temperature and time in the first stage so that the proportion of the polypropylene part (in the finally obtained copolymer) is 20 to 90% by mass, and then in the second stage, propylene and ethylene or other α-olefins are introduced, and polymerization is preferably carried out so that the proportion of the rubber part such as ethylene-propylene rubber (EPR) (in the finally obtained copolymer) is 10 to 80% by mass. The polymerization temperature in both the first stage and the second stage is preferably 200°C or lower, more preferably 100°C or lower, and even more preferably 65 to 80°C. The polymerization pressure is preferably 10 MPa or lower, more preferably 6 MPa or lower, and even more preferably 5 MPa or lower. In the above copolymerization reaction, either a continuous polymerization method or a batch polymerization method can be adopted, and the polymerization reaction may be carried out in one stage or in two or more stages. Also, the polymerization time (residence time in the reactor) is preferably 1 minute to 5 hours in each polymerization stage of the first stage or the second stage, or even during continuous polymerization. Examples of the polymerization method include a slurry polymerization method using a solvent of an inert hydrocarbon compound such as cyclohexane and heptane, a bulk polymerization method using a solvent such as liquefied propylene, and a gas-phase polymerization method that substantially does not use a solvent. The bulk polymerization method or the gas-phase polymerization method is preferred.

[0103] Particularly, the ethylene-propylene block copolymer contains an EPR component (copolymer component of ethylene and propylene). When the EPR component exudes onto the surface of the polymer particles, stickiness (adhesiveness) of the particles occurs and the fluidity deteriorates. Since the deterioration of the fluidity of the particles in the polymer production equipment is a factor that reduces the operability of the plant, it is desirable to select a polymer production method that can suppress the exudation of the EPR component onto the particle surface.

[0104] In this application document, the ethylene-propylene rubber component (EPR) content in the ethylene-propylene copolymer means the value calculated by the following method. <EPR content> In a 1-liter flask equipped with a stirrer and condenser, approximately 2.5 g of copolymer, 8 mg of 2,6-di-t-butyl-p-cresol, and 250 mL of p-xylene were added and stirred below boiling point until the copolymer was completely dissolved. Next, the flask was cooled to room temperature and left for 15 hours to precipitate solid material. This was then separated into solid and liquid phase portions using a centrifuge. The separated solid material was placed in a beaker, 500 mL of acetone was added, and the mixture was stirred at room temperature for 15 hours. The solid material was then filtered and dried, and its dry mass was measured (this mass is denoted as B(g)). The same procedure was performed on the separated liquid phase portion, and after precipitation of solid material, it was dried and its dry mass was measured (this mass is denoted as C(g)). The ethylene-propylene rubber component (EPR) content in the copolymer was calculated using the following formula (1). EPR content (mass%)=[C(g) / {B(g)+C(g)}]×100 (1)

[0105] It is generally known that when olefins are copolymerized using a solid catalyst component for olefin polymerization that contains internal electron-donating compounds other than phthalate esters, the resulting copolymers exhibit inferior block rates and EPR content compared to when olefins are copolymerized using a solid catalyst component for olefin polymerization that contains phthalate esters as the internal electron-donating compound. In contrast, the present invention makes it possible to easily produce copolymers with excellent block ratio and EPR content by copolymerizing propylene with monomers of other α-olefins using a solid catalyst component for olefin polymerization that includes a specific solid catalyst component for olefin polymerization, an organoaluminum compound, and one or more external electron-donating compounds selected from the aminosilane compounds represented by the general formula (I) above.

[0106] In the method for producing an olefin polymer according to the present invention, when the obtained olefin polymer is a copolymer of propylene and a monomer of another α-olefin, the flexural modulus (FM) of the copolymer is preferably 1300 MPa or more, more preferably 1300 to 2500 MPa, and still more preferably 1500 to 2000 MPa.

[0107] When the flexural modulus (FM) of the copolymer of propylene and a monomer of another α-olefin is within the above range, excellent rigidity can be easily exhibited.

[0108] In the present application documents, the flexural modulus (FM) of the above copolymer is measured by using NEX30III3EG manufactured by Nissei Plastic Industrial Co., Ltd., injection molding a multi-purpose test piece type A1 defined in JIS K7139 under the conditions of a molding temperature of 200°C and a mold temperature of 40°C, cutting out a test piece with a thickness of 4.0 mm, a width of 10.0 mm, and a length of 80 mm from the central part of the test piece, and performing state adjustment for 72 hours in a thermostatic chamber adjusted to 23°C for the cut-out test piece, and then measuring the value at a measurement ambient temperature of 23°C based on JIS K7171 (the unit is MPa).

[0109] In the method for producing an olefin polymer according to the present invention, when the obtained olefin polymer is a copolymer of propylene and a monomer of another α-olefin, the IZOD impact strength of the copolymer is 1.0 to 8.0 kJ / m 2 which is preferably, more preferably 2.0 to 7.0 kJ / m 2 and still more preferably 2.0 to 6.0 kJ / m. 2 In the present application documents, the IZOD impact strength of the copolymer of propylene and a monomer of another α-olefin means the value measured by the following method.

[0110] <Measurement method of IZOD impact strength> <IZOD (Izod) impact strength measurement method> The copolymer is mixed with 0.10% by weight of IRGANOX 1010 (manufactured by BASF), 0.10% by weight of IRGAFOS 168 (manufactured by BASF), and 0.08% by weight of calcium stearate, and then kneaded and granulated using a twin-screw extruder to obtain a pelletized copolymer. Next, the pelletized copolymer is introduced into an injection molding machine maintained at a mold temperature of 40°C and a cylinder temperature of 200°C, and multi-purpose test specimens of type A1 as specified in JIS K7139 are injection molded. After molding, the multipurpose test specimens are conditioned for 72 hours in a constant temperature chamber adjusted to 23°C. Then, using an automatic notching machine (manufactured by Yasuda Seiki Seisakusho Co., Ltd.), the test specimens are shaped as shown below. The notched test specimens are then measured using an IZOD testing machine (Yasuda Seiki Seisakusho Co., Ltd., low-temperature chamber impact testing machine, model 258-L) in accordance with JIS K7110, measuring the Izod impact strength of the test specimens at 23°C and -30°C. Specimen shape: ISO 180 / 1A, thickness 4.0 mm, width 8.0 mm, length 80.0 mm Notch shape: Type A notch (notch radius 0.25 mm) Temperature conditions: 23°C and 30°C Impact velocity: 3.5 m / s Nominal pendulum energy: 5.5, 2.75, or 1.0 J at 23°C, 1.0 or 0.5 J at -30°C.

[0111] It is generally known that when olefins are copolymerized using a solid catalyst component for olefin polymerization that contains internally electron-donating compounds other than phthalate esters, the resulting copolymer exhibits inferior IZOD impact strength compared to when olefins are copolymerized using a solid catalyst component for olefin polymerization that contains phthalate esters as the internally electron-donating compound. In contrast, in the present invention, a copolymer with excellent IZOD impact strength can be easily produced by copolymerizing propylene with monomers of other α-olefins, using a solid catalyst component for olefin polymerization that includes a specific solid catalyst component for olefin polymerization, an organoaluminum compound, and one or more external electron-donating compounds selected from the aminosilane compounds represented by the general formula (I) above.

[0112] According to the present invention, since the catalyst for olefin polymerization according to the present invention is used, it is possible to provide a method for producing olefin polymers that have excellent melt flowability and moldability, as well as even better flexural modulus, in a simple manner.

[0113] Next, the propylene homopolymer according to the present invention will be described. The propylene homopolymer according to the present invention is (a) Melt flow rate is 300 g / 10 minutes or less, (b) Flexural modulus of 1900 MPa or more, (c) The ratio of the complex viscosity η* at an angular frequency of 0.01 radians / second to the complex viscosity η* at an angular frequency of 100 radians / second is 5.5 or greater. It is characterized by the following:

[0114] In the propylene homopolymer according to the present invention, the melt flow rate (MFR) indicating the melt flowability of the polymer is 300 g / 10 minutes or less, preferably 1 to 300 g / 10 minutes, and more preferably 10 to 200 g / 10 minutes.

[0115] In the propylene homopolymer according to the present invention, if the melt flow rate (MFR) is within the above range, sufficient moldability can be easily achieved in practical use.

[0116] In this application, the melt flow rate (MFR) refers to the value measured according to ASTM D 1238 and JIS K 7210.

[0117] The propylene homopolymer according to the present invention has a flexural modulus (FM) of 1900 MPa or more, preferably 1900 to 2500 MPa, and more preferably 2000 to 2400 MPa.

[0118] In the propylene homopolymer according to the present invention, excellent rigidity can be easily achieved because the flexural modulus (FM) is within the above range.

[0119] 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).

[0120] The propylene homopolymer according to the present invention satisfies the above-mentioned requirements for flexural modulus, thereby easily exhibiting excellent rigidity.

[0121] The propylene homopolymer according to the present invention has a ratio of the complex viscosity η* at an angular frequency of 0.01 radian / second to the complex viscosity η* at an angular frequency of 100 radian / second (complex viscosity η* at an angular frequency of 0.01 radian / second / complex viscosity η* at an angular frequency of 100 radian / second), i.e., a complex viscoelastic ratio of 5.5 or higher, preferably 5.5 to 20, and more preferably 5.5 to 15.

[0122] In the propylene homopolymer according to the present invention, excellent tensile strength can be easily achieved by having a complex viscoelastic ratio of 5.5 or higher.

[0123] In this application, the complex viscoelastic ratio refers to the value measured by the method described below.

[0124] (Hybrid viscoelastic ratio of olefin polymers) The complex viscosity η*, which defines the complex viscoelastic ratio of olefin polymers, is measured using a rheometer (MCR302, Anton Paar). The olefin polymer is compressed and molded at 210°C for 5 minutes using a press, ensuring no air bubbles are introduced, to create a disc-shaped sample for measurement with a thickness of 2 mm and a diameter of 25 mm. The measurements will be performed using an Anton Paar rheometer (MCR302). Using parallel discs with a diameter of 25 mm placed with a 1 mm gap between them, and filling the gap with the measurement sample, the complex viscosity η was measured at a measurement temperature of 190°C and in a frequency range from 0.01 radians / second to 100 radians / second. * Measure. The complex viscoelastic ratio is calculated as the ratio of the complex viscosity η* at an angular frequency of 0.01 radian / second under the above temperature conditions of 190°C to the complex viscosity η* at an angular frequency of 100 radian / second under the temperature conditions of 190°C (complex viscosity η* at an angular frequency of 0.01 radian / second under the temperature conditions of 190°C / complex viscosity η* at an angular frequency of 100 radian / second under the temperature conditions of 190°C).

[0125] The propylene homopolymer according to the present invention preferably has a molecular weight distribution expressed as Mw / Mn, which is the ratio of weight-average molecular weight Mw to number-average molecular weight Mn, of 7.0 to 15.0, more preferably 7.5 to 12.0, and even more preferably 8.0 to 11.0. Furthermore, the propylene homopolymer according to the present invention preferably has a molecular weight distribution expressed as Mz / Mw, which is the ratio of the Z-average molecular weight Mz to the weight-average molecular weight Mw, of 4.0 to 10.0, more preferably 4.5 to 9.0, and even more preferably 5.0 to 8.0.

[0126] The propylene homopolymer according to the present invention can easily exhibit the broad molecular weight distribution described above.

[0127] In this application, the molecular weight distribution of the propylene homopolymer refers to the values ​​calculated from the mass-average molecular weight Mw, number-average molecular weight Mn, and Z-average molecular weight Mz, which are obtained by measuring under the following conditions using gel permeation chromatography (GPC) (Waters GPCV2000). Solvent: o-dichlorobenzene (ODCB) Temperature: 140℃ (SEC) Column: Shodex GPC UT-806M Sample concentration: 1 g / liter-ODCB (50 mg / 50 mL-ODCB) Injection volume: 0.5mL Flow rate: 1.0mL / min

[0128] The propylene homopolymer according to the present invention can be easily produced by the method for producing olefin polymers according to the present invention.

[0129] According to the present invention, it is possible to provide a propylene homopolymer that is excellent in melt flowability and moldability, as well as having an even better flexural modulus. [Examples]

[0130] 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.

[0131] (Example 1) 1. Synthesis of solid catalyst components As an internally electron-donating compound, diethyl 2,3-diisopropyl succinate, a succinic acid diester compound, was used to prepare a solid catalyst component for olefin polymerization by the following method. (i) A mixed solution was formed by charging 40.0 mL (365 mmol) of titanium tetrachloride and 50.0 mL of toluene into a 500 mL flask equipped with a stirring device and purged with nitrogen gas. (ii) Next, a suspension formed by mixing 20 g (174.8 mmol) of diethoxymagnesium, 60 mL of toluene, and 3.0 mL (11.2 mmol) of diethyl 2,3-diisopropylsuccinate was added to the above mixed solution, which was maintained at a liquid temperature of -6°C, to obtain a solution containing the initial contact substance. (iii) The initial contact solution was heated, and 3.0 mL (11.2 mmol) of diethyl 2,3-diisopropyl succinate was added at 60°C during the heating process. The temperature was then raised further to 100°C, and the mixture was allowed to react for 90 minutes while maintaining this temperature. After the reaction was complete, the supernatant was removed, and the first contact product, which was the reaction product, was washed four times with 150 mL of toluene at 90°C, and 100 mL of toluene was added. (iv) Next, 20 mL (182 mmol) of titanium tetrachloride was added to the first contact product, the temperature was raised to 100°C, and the reaction was carried out for 15 minutes. After the reaction was complete, the supernatant was removed, and this procedure was repeated three times to obtain the final contact product, which was the reaction product. Then, the obtained final contact product was washed six times with 150 mL of n-heptane at 40°C, and the solid and liquid were separated to obtain a solid catalyst component (solid catalyst component for olefin polymerization). The solid-liquid components obtained were separated, and the titanium content and succinate diester compound content in the resulting solid were measured to be 3.20% by mass and 17.4% by mass, respectively. Furthermore, the ratio of succinate diester compound content to titanium content was 1.01 in molar ratio. The properties of the obtained solid catalyst components are shown in Table 1.

[0132] The titanium content in the solid catalyst components, the content of internally electron-donating compounds such as succinate diester compounds, and their physical properties were measured using the method described below.

[0133] <Titanium content in solid catalyst components> The titanium content in the solid catalyst component was measured according to the method of JIS 8311-1997.

[0134] <Internal electron donating compound content> The content of internally electron-donating compounds was determined by gas chromatography (Shimadzu Corporation, GC-14B) under the following conditions. The number of moles of internally electron-donating compounds was determined from the gas chromatography results using a calibration curve previously measured at known concentrations. (Measurement conditions) • Column: Packed column (φ2.6 × 2.1m, 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

[0135] 2. Formation of polymerization catalyst and polymerization reaction A polymerization catalyst was prepared by charging a 2.0-liter autoclave with a stirrer, purged with nitrogen gas, with 1.3 mmol of triethylaluminum, 0.26 mmol of bis(ethylamino)dicyclopentylsilane as an aminosilane compound, and 0.0026 mmol of the above solid catalyst component (in terms of titanium atoms). Subsequently, 6.0 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. The polymerization activity per gram of solid catalyst component, the melt flow rate (MFR) of the polymer, the proportion of p-xylene soluble matter in the polymer (XS), the flexural modulus (FM) of the polymer, the molecular weight distribution (Mw / Mn, Mz / Mw) of the polymer, and the complex viscoelastic ratio (complex viscosity η* at an angular frequency of 0.01 radians / second / complex viscosity η* at an angular frequency of 100 radians / second) were measured using the following method. The results are shown in Table 2.

[0136] <Polymerization activity per gram of solid catalyst component> The polymerization activity per gram of solid catalyst component was determined using the following formula (2). Polymerization activity (g / g-cat) = Mass of polymer (g) / Mass of solid catalyst component (g) (2)

[0137] <Melting Flow Rate (MFR) of Polymers> 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.

[0138] <Percentage of p-xylene-soluble content in the polymer (XS)> 4.0 g of polymer (polypropylene) and 200 mL of p-xylene were placed in a flask equipped with a stirring device. Next, the external temperature was set to approximately 150°C, and stirring was continued for 2 hours while maintaining reflux of p-xylene (boiling point 137-138°C) in the flask to dissolve the polymer. After that, the solution was cooled over 1 hour until the liquid temperature reached 23°C, and the insoluble and soluble components were separated by filtration. A solution of the soluble components was collected, and p-xylene was removed by heating and vacuum drying. The weight of the resulting residue was determined, and its relative percentage (mass%) relative to the generated polymer (polypropylene) was calculated to determine the xylene-soluble content (XS).

[0139] <Flexural modulus (FM) of polymers> The flexural modulus (FM) of the polymer was measured using NEX30III3EG manufactured by Nissei Plastic Industrial Co., Ltd., by injection molding a multipurpose test specimen type A1 as specified in JIS K7139 under conditions of a molding temperature of 200°C and a mold temperature of 40°C. A test specimen measuring 4.0 mm thick, 10.0 mm wide, and 80.0 mm long was cut from the center of the test specimen. After conditioning the specimen in a constant temperature room adjusted to 23°C for 72 hours, the flexural modulus (FM) was measured at a measurement ambient temperature of 23°C according to JIS K7171 (unit: MPa).

[0140] <Molecular weight distribution of polymers> The molecular weight distribution of the polymer was determined by gel permeation chromatography (GPC) (Waters GPCV2000) under the following conditions, and evaluated by the ratio of mass-average molecular weight Mw to number-average molecular weight Mn (Mw / Mn) and the ratio of Z-average molecular weight Mz to mass-average molecular weight Mw (Mz / Mw). Solvent: o-dichlorobenzene (ODCB) Temperature: 140℃ (SEC) Column: Shodex GPC UT-806M Sample concentration: 1 g / liter-ODCB (50 mg / 50 mL-ODCB) Injection volume: 0.5mL Flow rate: 1.0mL / min

[0141] <Complex viscoelastic ratio (complex viscosity η at angular frequency of 0.01 radians / second) * Complex viscosity η at angular frequency of 100 radians / second * )> Complex viscosity η of olefin polymers * This was measured using a rheometer (Anton Paar MCR302). Olefin polymers were compressed and molded at 190°C for 5 minutes using a press, taking care to prevent air bubbles from forming, to create disc-shaped samples for measurement with a thickness of 2 mm and a diameter of 25 mm. The measurements were performed using an Anton Paar rheometer (MCR302). Using parallel discs with a diameter of 25 mm placed with a 1 mm gap between them, and filling the gap with the measurement sample, the complex viscosity η was measured at a measurement temperature of 190°C and in a frequency range from 0.01 radians / second to 100 radians / second. * We measured it. Furthermore, the complex viscoelastic ratio is calculated using the complex viscosity η at an angular frequency of 100 radians / second under the above temperature conditions of 190°C. * Complex viscosity η at an angular frequency of 0.01 radians / second under a temperature condition of 190°C * (Complex viscosity η at an angular frequency of 0.01 radians / second under a temperature of 190°C) * Complex viscosity η at an angular frequency of 100 radians / second under a temperature of 190°C * It was calculated as a ratio expressed as ).

[0142] (Example 2) In "2. Formation of Polymerization Catalyst and Polymerization Reaction" of Example 1, 0.13 mmol of bis(ethylamino)cyclohexylmethylsilane was used instead of 0.26 mmol of bis(ethylamino)dicyclopentylsilane as the external electron-donating compound, and the amount of hydrogen gas used in the formation of the propylene homopolymer was changed to 5.0 liters. Otherwise, the polymerization catalyst was formed and the polymerization reaction was carried out in the same manner as in Example 1. The polymerization activity per gram of the solid catalyst component and the physical properties of the resulting polymer were measured using the same method as in Example 1. The results are shown in Table 2.

[0143] (Example 3) 1. Synthesis of solid catalyst components As internal electron-donating compounds, diethyl 2,3-diisopropylsuccinate and (2-ethoxyethyl)ethyl carbonate, an ether carbonate compound, were used to prepare solid catalyst components for olefin polymerization by the following method. (i) A mixed solution was formed by charging 40.0 mL (365 mmol) of titanium tetrachloride and 50.0 mL of toluene into a 500 mL flask equipped with a stirring device and purged with nitrogen gas. (ii) Next, a suspension formed by mixing 20 g (174.8 mmol) of diethoxymagnesium and 60 mL of toluene was added to the above mixed solution, which was maintained at a liquid temperature of -6°C, to obtain a solution containing the initial contact substance. (iii) The initial contact solution was heated, and 3.2 mL (11.7 mmol) of diethyl 2,3-diisopropyl succinate was added at 60°C, and 2.5 mL (15.4 mmol) of (2-ethoxyethyl) ethyl carbonate was added at 80°C. The temperature was then further increased to 100°C, and the reaction was allowed to proceed for 90 minutes while maintaining this temperature. After the reaction was complete, the supernatant was removed, and the first contact product, which was the reaction product, was washed four times with 150 mL of toluene at 90°C. (iv) Next, 80 mL of toluene and 40 mL (365 mmol) of titanium tetrachloride were added to the first contact product, and the temperature was raised to 100°C and the reaction was carried out for 15 minutes. After the reaction was complete, the supernatant was removed, and this procedure was repeated four times to obtain the final contact product, which was the reaction product. Then, the obtained final contact product was washed six times with 150 mL of n-heptane at 40°C, and the solid and liquid were separated to obtain a solid catalyst component (solid catalyst component for olefin polymerization). The properties of the obtained solid catalyst components were measured in the same manner as in Example 1. The results are shown in Table 1. 2. Formation of polymerization catalyst and polymerization reaction Using the solid catalyst component obtained in 1. above, the polymerization catalyst was formed and the polymerization reaction was carried out in the same manner as in "2. Formation of polymerization catalyst and polymerization reaction" of Example 1, except that the amount of hydrogen gas used during the formation of the propylene homopolymer was changed to 4.5 liters. The polymerization activity per gram of the solid catalyst component and the physical properties of the resulting polymer were measured using the same method as in Example 1. The results are shown in Table 2.

[0144] (Comparative Example 1) In Example 3, "2. Formation of Polymerization Catalyst and Polymerization Reaction," the polymerization catalyst was formed and the polymerization reaction was carried out in the same manner as in Example 3, except that 0.13 mmol of dicyclopentyldimethoxysilane was used as the external electron-donating compound instead of 0.13 mmol of bis(ethylamino)dicyclopentylsilane, and the amount of hydrogen gas charged during the formation of the propylene homopolymer was changed to 9.0 liters. The polymerization activity per gram of the solid catalyst component and the physical properties of the resulting polymer were measured using the same method as in Example 1. The results are shown in Table 2.

[0145] (Example 4) 1. Synthesis of solid catalyst components A solid catalyst component (solid catalyst component for olefin polymerization) was obtained in the same manner as in Example 1, except that the amount of diethyl 2,3-diisopropylsuccinate added in "1. Synthesis of Solid Catalyst Component" (ii) and (iii) of Example 1 was changed from 3.0 mL (11.2 mmol) to 3.6 mL (13.3 mmol) in both cases. The properties of the obtained solid catalyst components were measured in the same manner as in Example 1. The results are shown in Table 1. 2. Formation of polymerization catalyst and polymerization reaction Except for using the solid catalyst component obtained in 1. above, the polymerization catalyst was formed and the polymerization reaction was carried out in the same manner as in "2. Formation of polymerization catalyst and polymerization reaction" of Example 1. The polymerization activity per gram of the solid catalyst component and the physical properties of the resulting polymer were measured using the same method as in Example 1. The results are shown in Table 2.

[0146] (Comparative Example 2) 1. Synthesis of solid catalyst components In Example 1, "1. Synthesis of Solid Catalyst Component" (iii), a solid catalyst component (solid catalyst component for olefin polymerization) was obtained in the same manner as in Example 1, except that 3.0 mL (11.2 mmol) of diethyl 2,3-diisopropylsuccinate was not added at 60°C during the heating process. The properties of the obtained solid catalyst components were measured in the same manner as in Example 1. The results are shown in Table 1. 2. Formation of polymerization catalyst and polymerization reaction Using the solid catalyst component obtained in 1. above, the polymerization catalyst was formed and the polymerization reaction was carried out in the same manner as in "2. Formation of polymerization catalyst and polymerization reaction" of Example 1, except that the amount of hydrogen gas charged during the formation of the propylene homopolymer was changed to 3.0 liters. The polymerization activity per gram of the solid catalyst component and the physical properties of the resulting polymer were measured using the same method as in Example 1. The results are shown in Table 2.

[0147] (Example 5) 1. Synthesis of solid catalyst components (i) In a 300 mL round-bottom flask equipped with a stirrer and purged with nitrogen gas, 5.7 g (60.0 mmol) of anhydrous magnesium chloride, 30 mL of n-decane, and 28 mL (179.0 mmol) of 2-ethylhexyl alcohol were charged and heated at 130 °C for 2 hours to obtain a homogeneous solution. Then, 2.4 mL (8.8 mmol) of diethyl diisopropylsuccinate was added to this solution and stirred at 130 °C for a further 1 hour. (ii) The homogeneous solution thus obtained was cooled to room temperature and then added dropwise over 1 hour to 240 mL (2.2 mol) of titanium tetrachloride, which was kept at -20°C. The temperature of this mixture was raised to 110°C over 2 hours, and when it reached 90°C, 3.2 mL (11.9 mmol) of diethyl diisopropyl succinate was added, and the mixture was stirred at 110°C for 2 hours. After the reaction was complete, the supernatant was removed. (iii) Next, 240 mL (2.2 mol) of titanium tetrachloride was added, and the reaction was carried out again at 110°C for 2 hours. The product was washed twice with 100 mL of toluene at 110°C, and then washed four times with 100 mL of n-heptane at 40°C to obtain a solid catalyst component (solid catalyst component for olefin polymerization). The properties of the obtained solid catalyst components were measured in the same manner as in Example 1. The results are shown in Table 1. 2. Formation of polymerization catalyst and polymerization reaction Using the solid catalyst component obtained in 1. above, the polymerization catalyst was formed and the polymerization reaction was carried out in the same manner as in "2. Formation of polymerization catalyst and polymerization reaction" of Example 1, except that the amount of hydrogen gas charged during the formation of the propylene homopolymer was changed to 6.5 liters. The polymerization activity per gram of the solid catalyst component and the physical properties of the resulting polymer were measured using the same method as in Example 1. The results are shown in Table 2.

[0148] (Example 6) 1. Synthesis of solid catalyst components (i) A mixed solution was formed by charging 75.0 mL (684 mmol) of titanium tetrachloride and 15.0 mL of toluene into a 500 mL flask equipped with a stirring device and purged with nitrogen gas. (ii) Next, a suspension formed by mixing 20 g (174.8 mmol) of diethoxymagnesium, 60 mL of toluene, and 2.7 mL (10.2 mmol) of diethyl 2,3-diisopropylsuccinate was added to the above mixed solution, which was maintained at a liquid temperature of -6°C, to obtain a solution containing the initial contact substance. (iii) The initial contact solution was heated, and 2.7 mL (10.2 mmol) of diethyl 2,3-diisopropyl succinate was added at 60°C during the heating process. The temperature was then raised further to 100°C, and the mixture was allowed to react for 90 minutes while maintaining this temperature. After the reaction was complete, the supernatant was removed, and the first contact product, which was the reaction product, was washed four times with 150 mL of toluene at 90°C, and 80 mL of toluene was added. (iv) Next, 40 mL (365 mmol) of titanium tetrachloride was added to the first contact product, the temperature was raised to 100°C, and the reaction was carried out for 15 minutes. After the reaction was complete, the supernatant was removed, and this procedure was repeated three times to obtain the final contact product, which was the reaction product. Then, the obtained final contact product was washed six times with 150 mL of n-heptane at 40°C, and the solid and liquid were separated to obtain a solid catalyst component (solid catalyst component for olefin polymerization). The solid-liquid components obtained were separated, and the titanium content and succinate diester compound content in the resulting solid were measured to be 4.63% by mass and 20.5% by mass, respectively. Furthermore, the ratio of succinate diester compound content to titanium content was 0.82 in molar ratio. The properties of the obtained solid catalyst components were measured in the same manner as in Example 1. The results are shown in Table 1. 2. Formation of polymerization catalyst and polymerization reaction Using the solid catalyst component obtained in step 1 above, a polymerization catalyst was formed and a polymerization reaction was carried out in the same manner as in "2. Formation of polymerization catalyst and polymerization reaction" of Example 1. The polymerization activity per gram of the solid catalyst component and the physical properties of the resulting polymer were measured using the same method as in Example 1. The results are shown in Table 2.

[0149] (Example 7) In Example 6, in "2. Formation of Polymerization Catalyst and Polymerization Reaction," 0.13 mmol of bis(ethylamino)dicyclopentylsilane was used instead of 0.26 mmol of bis(ethylamino)dicyclopentylsilane as the external electron-donating compound, and the amount of hydrogen gas used during the formation of the propylene homopolymer was changed from 6.0 liters to 4.5 liters. Otherwise, the polymerization catalyst was formed and the polymerization reaction was carried out in the same manner as in Example 1. The polymerization activity per gram of the solid catalyst component and the physical properties of the resulting polymer were measured using the same method as in Example 1. The results are shown in Table 2.

[0150] (Reference example 1) 1. Synthesis of solid catalyst components In a 200 mL round-bottom flask equipped with a stirrer and thoroughly purged with nitrogen gas, 10 g (87.4 mmol) of diethoxymagnesium, 2.5 mL (9.4 mmol) of di-n-butyl phthalate, and 50 mL of toluene were charged to form a suspension. Next, this suspension was added to a homogeneous solution of 30 mL of toluene and 20 mL (0.18 mol) of titanium tetrachloride, which was pre-loaded in a 500 mL round-bottom flask equipped with a stirrer and thoroughly purged with nitrogen gas. Next, the mixture was heated while stirring, and 1.2 mL (4.5 mmol) of di-n-butyl phthalate was added at 60°C. The temperature was then further increased to 110°C, and the reaction was maintained at this temperature for 2 hours. After the reaction was complete, the supernatant was removed, and the product was washed four times with 100 mL of toluene at 105°C. Next, 40 mL of toluene and 20 mL (0.18 mol) of titanium tetrachloride were added, and the temperature was raised to 105°C while stirring. After reacting at 105°C for 2 hours, the product was washed eight times with 75 mL of n-heptane at 40°C to obtain a solid catalyst component (solid catalyst component for olefin polymerization). The properties of the obtained solid catalyst components were measured in the same manner as in Example 1. The results are shown in Table 1. 2. Formation of polymerization catalyst and polymerization reaction Using the solid catalyst component obtained in 1. above, the polymerization catalyst was formed and the polymerization reaction was carried out in the same manner as in "2. Formation of polymerization catalyst and polymerization reaction" of Example 1, except that the amount of hydrogen gas charged during the formation of the propylene homopolymer was changed to 4.5 liters. The polymerization activity per gram of the solid catalyst component and the physical properties of the resulting polymer were measured using the same method as in Example 1. The results are shown in Table 2.

[0151] (Reference example 2) In Reference Example 1, "2. Formation of Polymerization Catalyst and Polymerization Reaction," the polymerization catalyst was formed and the polymerization reaction was carried out in the same manner as in Reference Example 1, except that cyclohexylmethyldimethoxysilane was used as the external electron-donating compound in the same mole as 0.26 mmol of bis(ethylamino)dicyclopentylsilane, and the amount of hydrogen gas charged was changed to 11 liters. The polymerization activity per gram of the solid catalyst component and the physical properties of the resulting polymer were measured using the same method as in Example 1. The results are shown in Table 2.

[0152] (Reference example 3) In Reference Example 1, "2. Formation of Polymerization Catalyst and Polymerization Reaction," the polymerization catalyst was formed and the polymerization reaction was carried out in the same manner as in Reference Example 1, except that 0.26 mmol of bis(ethylamino)dicyclopentylsilane was used as the external electron-donating compound, the same mole of diisopropyldimethoxysilane was used, and the amount of hydrogen gas charged was changed to 9 liters. The polymerization activity per gram of the solid catalyst component and the physical properties of the resulting polymer were measured using the same method as in Example 1. The results are shown in Table 2.

[0153] [Table 1]

[0154] [Table 2]

[0155] (Example 8) <Preparation of Ethylene-Propylene Copolymer Catalyst> An ethylene-propylene copolymer catalyst was prepared by charging a 2.0-liter autoclave with a stirrer, which was purged with nitrogen gas, with 2.4 mmol of triethylaluminum, 0.24 mmol of bis(ethylamino)dicyclopentylsilane as an aminosilane compound, and 0.003 mmol (in terms of titanium atoms) of the solid catalyst component prepared in Example 1.

[0156] <Ethylene-propylene copolymer> 1. Homopolymerization reaction (homostep polymerization) In an autoclave equipped with a stirrer containing the ethylene-propylene copolymerization catalyst prepared above, 15 moles (1.2 liters) of liquefied propylene and hydrogen gas at 0.20 MPa (partial pressure) were charged, and prepolymerization was carried out at 20°C for 5 minutes. After that, the temperature was raised and the first stage of propylene homopolymerization (homo-stage polymerization) was carried out at 70°C for 45 minutes. After returning to atmospheric pressure, the inside of the autoclave (reactor) was purged with nitrogen, and the autoclave was weighed. The polymerization activity of the homo-stage (first stage) (homo-activity, g / g-cat) was calculated using the following formula by subtracting the tare mass of the autoclave. To evaluate polymerization performance and polymer properties, a portion of the generated polymer was separated, and its melt flow rate (MFR) was evaluated by the following method. <Homoactivity (polymerization activity per gram of solid catalyst component)> The homoactivity (polymerization activity per gram of solid catalyst component) was determined using the following formula (3). Polymerization activity (g-pp / g-catalyst) = Mass of polymer (g) / Mass of solid catalyst component (g) (3) <Melting Flow Rate (MFR) of Polymers> 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. 2. Ethylene-propylene copolymerization reaction Next, ethylene and propylene were added to the autoclave (reactor) in a molar ratio of 0.42 / 0.58, respectively. The temperature was then raised to 70°C, and ethylene, propylene, and hydrogen were introduced at gas supply rates (liters / minute) of 1.7 / 2.3 / 0.086 respectively. The reaction was carried out under conditions of 1.2 MPa, 70°C, and 60 minutes to obtain an ethylene-propylene copolymer. The copolymerization (ICP) activity (g / g-cat), melt flow rate (MFR), block rate (mass%), EPR content (mass%), and IZOD impact strength of the copolymer were measured in the obtained ethylene-propylene copolymer using the following methods. The results are shown in Table 3.

[0157] <Copolymerization (ICP) activity (g / g-cat)> The copolymerization (ICP) activity during the formation of ethylene-propylene block copolymer was calculated by the following formula (4). Copolymerization (ICP) activity (g / g-cat) = ((I(g) - G(g)) / mass of solid catalyst component contained in the catalyst for olefin polymerization (g)) / reaction time (hours) (4) Here, I(g) is the autoclave mass (g) after the copolymerization reaction is completed, and G(g) is the autoclave mass (g) after removing unreacted monomers after the homopolymer PP polymerization reaction is completed.

[0158] <Melt flowability (MFR) of copolymer> The melt flow rate (MFR) (g / 10 min) indicating the melt flowability of the copolymer was measured according to ASTM D 1238 and JIS K 7210.

[0159] <Block ratio (mass%)> The block ratio of the ethylene-propylene copolymer was calculated by the following formula (5). Block ratio (mass%) = {(I(g) - G(g)) / (I(g) - F(g))} × 100 (5) Here, I is the autoclave mass (g) after the copolymerization reaction is completed, G is the autoclave mass (g) after removing unreacted monomers after the homopolypropylene polymerization is completed, and F is the autoclave mass (g).

[0160] <EPR content rate> In a 1-liter flask equipped with a stirrer and condenser, approximately 2.5 g of copolymer, 8 mg of 2,6-di-t-butyl-p-cresol, and 250 mL of p-xylene were added and stirred below boiling point until the copolymer was completely dissolved. Next, the flask was cooled to room temperature and left for 15 hours to precipitate solid material. This was then separated into solid and liquid phase portions using a centrifuge. The separated solid material was placed in a beaker, 500 mL of acetone was added, and the mixture was stirred at room temperature for 15 hours. The solid material was then filtered and dried, and its dry mass was measured (this mass is denoted as B(g)). The same procedure was performed on the separated liquid phase portion, and after precipitation of solid material, it was dried and its dry mass was measured (this mass is denoted as C(g)). The ethylene-propylene rubber component (EPR) content in the copolymer was calculated using the following formula (1). EPR content (mass%)=[C(g) / {B(g)+C(g)}]×100 (1)

[0161] <Flexural modulus (FM) of copolymers> In this application, the flexural modulus (FM) of the copolymer is determined by injection molding a multi-purpose test specimen type A1 as specified in JIS K7139 using NEX30III3EG manufactured by Nissei Plastic Industrial Co., Ltd., at 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 was 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 measured at a measurement ambient temperature of 23°C according to JIS K7171 (unit: MPa).

[0162] <IZOD impact strength of copolymers> The copolymer is mixed with 0.10% by weight of IRGANOX 1010 (manufactured by BASF), 0.10% by weight of IRGAFOS 168 (manufactured by BASF), and 0.08% by weight of calcium stearate, and then kneaded and granulated using a twin-screw extruder to obtain a pelletized copolymer. Next, the pelletized copolymer is introduced into an injection molding machine maintained at a mold temperature of 40°C and a cylinder temperature of 200°C, and multi-purpose test specimens of type A1 as specified in JIS K7139 are injection molded. After molding, the multipurpose test specimens were conditioned for 72 hours in a constant temperature chamber adjusted to 23°C. Then, using an automatic notching machine (manufactured by Yasuda Seiki Seisakusho Co., Ltd.), the test specimens were shaped into the form shown below. The Izod impact strength of the notched test specimens was measured at 23°C and -30°C in accordance with JIS K7110 using an Izod testing machine (Yasuda Seiki Seisakusho Co., Ltd., low-temperature chamber impact testing machine, model 258-L). Specimen shape: ISO 180 / 1A, thickness 4.0 mm, width 8.0 mm, length 80.0 mm Notch shape: Type A notch (notch radius 0.25 mm) Temperature conditions: 23°C and 30°C Impact velocity: 3.5 m / s Nominal pendulum energy: 5.5, 2.75, or 1.0 J at 23°C, 1.0 or 0.5 J at -30°C.

[0163] (Comparative Example 3) In Example 6, "2. Formation of Polymerization Catalyst and Polymerization Reaction," the ethylene-propylene polymerization catalyst was formed and the copolymerization reaction was carried out in the same manner as in Example 6, except that cyclohexylmethyldimethoxysilane was used in the same mole as 0.24 mmol of bis(ethylamino)dicyclopentylsilane as the external electron-donating compound. The polymerization activity and the physical properties of the resulting copolymer were measured using the same method as in Example 6. The results are shown in Table 3.

[0164] (Reference example 4) <Preparation of Ethylene-Propylene Copolymer Catalyst> An ethylene-propylene copolymer catalyst was prepared by charging a 2.0-liter autoclave with a stirrer, completely purged with nitrogen gas, with 2.4 mmol of triethylaluminum, 0.24 mmol of cyclohexylmethyldimethoxysilane as a silane compound, and 0.003 mmol (in terms of titanium atoms) of the solid catalyst component prepared in Reference Example 1.

[0165] <Ethylene-propylene copolymer> A copolymerization reaction was carried out in the same manner as in Example 6, except that the above ethylene-propylene copolymerization catalyst was used. The polymerization activity at this time and the physical properties of the obtained copolymer were measured by the same method as in Example 6. The results are shown in Table 3.

[0166]

Table 3

[0167] From Tables 1 to 2, the olefin polymerization catalyst according to the present invention used in Examples 1 to 7 contains magnesium, titanium, halogen, and a diester compound of succinic acid, and the ratio represented by the total content of the internal electron donating compound mainly composed of the diester compound of succinic acid / the content of titanium is 0.60 to 1.30 in molar ratio. It contains a solid catalyst component for olefin polymerization, an organoaluminum compound, and one or more external electron donating compounds selected from specific aminosilane compounds represented by the general formula (I). Therefore, although it contains a solid catalyst component for olefin polymerization containing a compound other than phthalic acid ester as an internal electron donating compound, it is excellent in melt flowability and moldability, and (even when compared with the case of using the olefin polymerization catalysts obtained in Reference Examples 1 to 3 containing a solid catalyst component for olefin polymerization containing phthalic acid ester as an internal electron donating compound), it can be seen that a propylene homopolymer having an even more excellent flexural modulus can be easily produced. Also, from Table 3, the olefin polymerization catalyst according to the present invention used in Example 8 contains the above specific components. Therefore, although it contains a solid catalyst component for olefin polymerization containing a compound other than phthalic acid ester as an internal electron donating compound, it can be seen that the obtained copolymer is excellent in block ratio and EPR, and is also excellent in the flexural modulus (FM) and IZOD impact strength of the copolymer.

[0168] On the other hand, as can be seen from Tables 1 and 2, the olefin polymerization catalysts used in Comparative Examples 1 and 2 either used compounds other than specific aminosilane compounds as external electron-donating compounds (Comparative Example 1), or the ratio expressed as the content of internal electron-donating compounds, mainly succinate diester compounds, that constitute the solid catalyst component / the content of titanium was outside the specified range (Comparative Example 2). Therefore, compared to Examples 1 to 5, the resulting propylene homopolymers had lower flexural modulus FM and complex viscoelastic ratio. Furthermore, as can be seen from Table 3, the olefin polymerization catalyst used in Comparative Example 3 uses a compound other than a specific aminosilane compound as the external electron-donating compound. As a result, compared to Example 6, the resulting copolymer has a lower block ratio and EPR, and the IZOD impact strength of the copolymer is also lower. [Industrial applicability]

[0169] According to the present invention, despite containing a solid catalyst component for olefin polymerization that includes compounds other than phthalate esters as internal electron-donating compounds, it is possible to easily produce a propylene homopolymer that is excellent in melt flowability and moldability, as well as having an even better flexural modulus. Furthermore, the present invention provides a method for producing olefin polymers and a propylene homopolymer.

Claims

[Claim 1] (a) Melt flow rate is 300 g / 10 minutes or less, (b) Flexural modulus of elasticity of 1900 MPa or more, (c) The ratio of the complex viscosity η* at an angular frequency of 0.01 radians / second to the complex viscosity η* at an angular frequency of 100 radians / second is 5.5 or greater. A propylene mono-treatment characterized by the following:

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