JP2024108453A - Solid catalyst component for olefin polymerization, method for producing solid catalyst component for olefin polymerization, catalyst for olefin polymerization, method for producing olefin polymer, and olefin polymer - Google Patents

Abstract

To provide a solid catalyst constituent for olefin polymerization containing an inner electron-donating compound other than a phthalic acid ester, and capable of easily producing an olefin polymer excellent in melt flow characteristics, and high in rigidity, and further a solid catalyst constituent for olefin polymerization capable of improving copolymerization performance of a solid catalyst for olefin polymerization.SOLUTION: A solid catalyst constituent includes: magnesium; titanium; halogen; and a succinic acid diester compound, where the content of the succinic acid diester compound in a total content in terms of solid content is 13.0 mass% or more, the content of a titanium atom is 3.0-6.0 mass%, and the molar ratio (S/T) expressed by a molar content (S) of the succinic acid ester compound in a total content to a molar content (T) of the titanium in a total content is 0.50-0.72.SELECTED DRAWING: None

Description

The present invention relates to a solid catalyst component for olefin polymerization, a method for producing a solid catalyst component for olefin polymerization, a catalyst for olefin polymerization, a method for producing an olefin polymer, and an olefin polymer.

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

Polypropylene resin compositions are lightweight and have excellent moldability, and the molded products have excellent chemical stability, including heat resistance and chemical resistance, and are also very cost-effective, making them one of the most important plastic materials and used in many fields.

To further expand its applications, there is a demand for polypropylene that has high melt flow rate (melt flow rate (MFR)), excellent moldability, and high rigidity, and can be used as a replacement for polystyrene and ABS resin.

In the polymerization of olefins such as propylene, a polymerization method using a solid catalyst component containing magnesium atoms, titanium atoms, halogen atoms, and an internal electron donor compound as essential components is known, and many methods have been proposed for polymerizing or copolymerizing olefins in the presence of an olefin polymerization catalyst consisting of the above solid catalyst component, an organoaluminum compound, and an organosilicon compound.

For example, Patent Document 1 proposes a method for polymerizing propylene using an olefin polymerization catalyst that contains a solid titanium catalyst component carrying an internal electron donor compound such as a phthalate ester, and an organoaluminum compound and an organosilicon compound having at least one Si-O-C bond as cocatalyst components. Many documents, including Patent Document 1, propose a method for obtaining a highly stereoregular polymer with high polymerization activity using a phthalate ester as an internal electron donor compound.

Japanese Patent Application Publication No. 57-63310

However, di-n-butyl phthalate and benzyl butyl phthalate, which are types of phthalate esters, have been identified as Substances of Very High Concern (SVHC) substances under the European Registration, Evaluation, Authorization and Restriction of Chemicals (REACH) regulations, and there is an increasing demand to switch to catalyst systems that do not use SVHC substances in order to reduce the environmental impact.

The inventors therefore investigated solid catalyst components for olefin polymerization that contain internal electron donor compounds other than phthalic acid esters, and discovered that by using a succinic acid diester compound as the internal electron donor compound, polypropylene with high rigidity and a flexural modulus (FM) of 2000 MPa or more can be obtained.

However, it was found that such polypropylene had a low hydrogen response. Therefore, it was difficult to produce polypropylene that had both high melt flowability (melt flow rate (MFR)) and high rigidity using a solid catalyst component for olefin polymerization that contained an internal electron donor compound other than phthalate ester.

In addition, solid catalyst components for olefin polymerization that use succinic acid diester compounds as internal electron donor compounds need to be improved in that the copolymerization activity during copolymerization and the block rate of the resulting copolymer are not at a high level.

Under these circumstances, the present invention aims to provide a solid catalyst component for olefin polymerization that contains an internal electron donor compound other than phthalic acid ester and can easily produce an olefin polymer that has excellent melt flowability and high rigidity. The present invention also aims to provide a solid catalyst component for olefin polymerization that can improve the copolymerization performance of a solid catalyst for olefin polymerization.

As a result of intensive research conducted by the present inventors to solve the above technical problems, they found that the above technical problems can be solved by a solid catalyst component for olefin polymerization, which contains magnesium, titanium, a halogen, and a succinic acid diester compound, and in which, when converted into solid content, the content of the succinic acid diester compound in the total amount of components is 13.0% by mass or more, the content of titanium atoms is 3.0 to 6.0% by mass, and the molar ratio (S/T) expressed by the molar amount (S) of the succinic acid diester compound in the total amount of components to the molar amount (T) of the titanium in the total amount of components is 0.50 to 0.72, and they have completed the present invention based on this finding.

That is, the present invention provides
(1) Magnesium, titanium, halogen, succinic acid diester compound,
The content of the succinic acid diester compound in the total amount of components is 13.0% by mass or more, and the content of titanium atoms is 3.0 to 6.0% by mass, calculated as a solid content;
a molar ratio (S/T) represented by the molar amount (S) of the succinic acid diester compound in the total amount of components to the molar amount (T) of the titanium in the total amount of components is 0.50 to 0.72;
A solid catalyst component for olefin polymerization,
(2) The succinic acid diester compound is represented by the following general formula (1);
R ¹ -O-C(=O)-CHR ² CHR ³ -C(=O)-O-R ⁴ (1)
(In the formula, ^R2 and ^R3 are hydrogen atoms or alkyl groups having 1 to 4 carbon atoms and may be the same or different from each other, and ^R1 and ^R4 are linear or branched alkyl groups having 2 to 4 carbon atoms and may be the same or different from each other.)
The solid catalyst component for olefin polymerization according to (1), characterized in that the solid catalyst component is one or more compounds selected from the group consisting of compounds represented by the formula:
(3) The solid catalyst component for olefin polymerization according to (1), wherein the content of the succinic acid diester compound in the total amount of the components is 15.0% by mass or more and the content of titanium atoms is 4.0 to 6.0% by mass.
(4) A method for producing a solid catalyst component for olefin polymerization by contacting a dialkoxymagnesium, a titanium halide compound and a succinic acid diester compound with each other, comprising the steps of:
contacting the dialkoxymagnesium with the titanium halide compound multiple times;
When the dialkoxymagnesium is first contacted with a titanium halide compound, 2.0 to 5.0 moles of the titanium halide compound are used per 1.0 mole of the dialkoxymagnesium;
the total amount of titanium compounds used is 5.0 to 18.0 moles per 1.0 mole of the dialkoxymagnesium;
Furthermore, the amount of the succinic acid diester compound used is 0.100 to 0.200 mol per 1.0 mol of the dialkoxymagnesium,
adjusting the amounts of the titanium halide compound and the succinic acid diester compound used so that the molar ratio (S/T) represented by the molar amount (S) of the succinic acid diester compound to the molar amount (T) of titanium is 0.50 to 0.72;
A method for producing a solid catalyst component for olefin polymerization, comprising the steps of:
(5) a first step of adding titanium tetrachloride to a first mixed suspension obtained by mixing a dialkoxymagnesium with an inert aromatic hydrocarbon solvent in a ratio of the volume of the inert aromatic hydrocarbon solvent to the volume of titanium tetrachloride (inert aromatic hydrocarbon solvent/titanium tetrachloride) of 0.50 to 2.5, and contacting the two with each other to obtain an initial contact product-containing liquid;
a second step of adding a succinic acid diester compound to the initial contact product-containing liquid, contacting them with each other at 80 to 120° C., and then washing with an inert aromatic hydrocarbon solvent to obtain a first contact product;
a third step of mixing the first contact product with an inert aromatic hydrocarbon solvent to obtain a second mixed suspension, then mixing titanium tetrachloride therewith, bringing them into contact with each other, and then washing with an inert aromatic hydrocarbon solvent to obtain a solid catalyst component for olefin polymerization;
(4) A method for producing a solid catalyst component for olefin polymerization, comprising at least
(6) The method for producing a solid catalyst component for olefin polymerization according to (5), characterized in that, after the third step, the solid catalyst component for olefin polymerization obtained by carrying out the third step is washed with an inert organic solvent.
(7) (I) A solid catalyst component for olefin polymerization according to any one of (1) to (3), and (II) a compound represented by the following general formula (2):
R ⁵ _p AlQ _3-p (2)
(In the formula, R ⁵ is an alkyl group having 1 to 6 carbon atoms, Q is a hydrogen atom or a halogen, p is 0<p≦3, and when there are multiple R ^5s , each R ⁵ may be the same or different, and when there are multiple Qs, each Q may be the same or different.)
A catalyst for olefin polymerization, comprising an organoaluminum compound represented by the formula:
(8) (I) A solid catalyst component for olefin polymerization according to any one of (1) to (3), (II) a compound represented by the following general formula (2):
R ⁵ _p AlQ _3-p (2)
(In the formula, R ⁵ is an alkyl group having 1 to 6 carbon atoms, Q is a hydrogen atom or a halogen, p is 0<p≦3, and when there are multiple R ^5s , each R ⁵ may be the same or different, and when there are multiple Qs, each Q may be the same or different.)
and (III) an external electron donor compound.
(9) A method for producing an olefin polymer, comprising polymerizing an olefin using the olefin polymerization catalyst according to (7) or (8).
(10) (a) a melt flow rate of 150 to 200 g/10 min;
(b) a flexural modulus of 1700 to 2000 MPa;
(c) an olefin polymer, characterized in that in dynamic viscoelasticity measurement, the ratio (η ratio) of complex viscosity η* at 190°C and an angular frequency of 0.01 radian/sec to complex viscosity η* at 190°C and an angular frequency of 100 radian/sec is 4.0 to 6.0;
(11) The olefin polymer according to the above (10), wherein the proportion of an orientation layer in a cross section of an injection-molded plate made of the olefin polymer is 20% or more.
This provides:

According to the present invention, it is possible to provide a solid catalyst component for olefin polymerization that contains an internal electron donor compound other than phthalic acid ester and can easily produce an olefin polymer that has excellent melt flowability and high rigidity. Furthermore, according to the present invention, it is possible to provide a solid catalyst component for olefin polymerization that can improve the copolymerization performance of a solid catalyst for olefin polymerization.

FIG. 2 is a diagram for explaining a method for preparing a measurement sample for measuring the proportion of an oriented layer in a cross section of an injection-molded plate of an olefin polymer. FIG. 2 is a diagram for explaining a method for preparing a measurement sample for measuring the proportion of an oriented layer in a cross section of an injection-molded plate of an olefin polymer. FIG. 13 is a diagram for explaining a method for specifying the proportion of an orientation layer.

First, the solid catalyst component for olefin polymerization according to the present invention will be described.
The solid catalyst component for olefin polymerization according to the present invention comprises:
Contains magnesium, titanium, halogens, and succinic acid diester compounds.
The content of the succinic acid diester compound in the total amount of components is 13.0% by mass or more, and the content of titanium atoms is 3.0 to 6.0% by mass, calculated as a solid content;
a molar ratio (S/T) represented by the molar amount (S) of the succinic acid diester compound in the total amount of components to the molar amount (T) of the titanium in the total amount of components is 0.50 to 0.72;
The present invention is characterized by the following:

The solid catalyst component for olefin polymerization according to the present invention can be a contact reaction product obtained by contacting and reacting a raw material component that is a magnesium supply source, a raw material component that is a titanium and halogen supply source, and a succinic acid diester compound that is an internal electron donor compound in an organic solvent. Specifically, a dialkoxymagnesium is used as the raw material component that is a magnesium supply source, and a tetravalent titanium halogen compound is used as the raw material component that is a titanium and halogen supply source, and these raw materials are contacted with an internal electron donor compound containing a succinic acid diester compound.

Specific examples of dialkoxymagnesium, which is a raw material component that serves as a magnesium source in the solid catalyst component for olefin polymerization according to the present invention, include dimethoxymagnesium, diethoxymagnesium, dipropoxymagnesium, dibutoxymagnesium, ethoxymethoxymagnesium, ethoxypropoxymagnesium, butoxyethoxymagnesium, etc., with diethoxymagnesium being particularly preferred.

The dialkoxymagnesium may be obtained by reacting metallic magnesium with an alcohol in the presence of a halogen or a halogen-containing metal compound.

The dialkoxymagnesium is preferably in granular or powder form, and may be in an irregular or spherical shape.

When a spherical dialkoxymagnesium is used, a polymer powder having a better particle shape (more spherical) and a narrower particle size distribution is obtained, improving the ease of handling of the polymer powder produced during the polymerization operation and preventing blockages and other problems caused by fine particles contained in the produced polymer powder.

The above-mentioned spherical dialkoxymagnesium does not necessarily have to be perfectly spherical, and elliptical or potato-shaped ones can also be used.

The average particle size (average particle size D50) of the dialkoxymagnesium is preferably 1.0 to 200.0 μm, more preferably 5.0 to 150.0 μm, where the average particle size D50 refers to the particle size at 50% of the cumulative particle size in the volume cumulative particle size distribution measured using a laser light scattering diffraction method particle size measuring device.
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.

In addition, the dialkoxymagnesium preferably has a narrow particle size distribution with few fine and coarse particles.
Specifically, when measured using a laser light scattering diffraction method particle size measuring instrument, the dialkoxymagnesium preferably contains 20% or less, more preferably 10% or less, of particles with a particle size of 5.0 μm or less, while when measured using a laser light scattering diffraction method particle size measuring instrument, the dialkoxymagnesium preferably contains 20% or less, more preferably 10% or less, of particles with a particle size of 100.0 μm or more.
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 means a particle size of 90% of the integrated particle size in the volume integrated particle size distribution when measured using a laser light scattering diffraction method particle size measuring instrument. Also, D10 means a particle size of 10% of the integrated particle size in the volume integrated particle size distribution when measured using a laser light scattering diffraction method particle size measuring instrument.

The method for producing the above-mentioned spherical dialkoxymagnesium is exemplified in, for example, JP-A-62-51633, JP-A-3-74341, JP-A-4-368391, and JP-A-8-73388.

In the solid catalyst component for olefin polymerization according to the present invention, the dialkoxymagnesium preferably has a specific surface area of 5 m ² /g or more, more preferably 5 to 50 m ² /g, and even more preferably 10 to 40 m ² /g.
By using a dialkoxymagnesium having 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.

In this application, the specific surface area of dialkoxymagnesium refers to a value measured by the BET method. Specifically, the specific surface area of dialkoxymagnesium refers to a value measured by the BET method (automatic measurement) using an Automatic Surface Area Analyzer HM model-1230 manufactured by Mountech Corporation in the presence of a mixed gas of nitrogen and helium after first vacuum drying the measurement sample at 50°C for 2 hours.

The dialkoxymagnesium is preferably in the form of a solution or suspension during the reaction, and being in the form of a solution or suspension allows the reaction to proceed smoothly.

When the dialkoxymagnesium is a solid, it can be made into a dialkoxymagnesium solution by dissolving it in a solvent capable of solubilizing the dialkoxymagnesium, or it can be made into a dialkoxymagnesium suspension by suspending it in a solvent not capable of solubilizing the dialkoxymagnesium.
When the dialkoxymagnesium is liquid, it may be used as it is in the form of a dialkoxymagnesium solution, or it may be further dissolved in a solvent capable of solubilizing the dialkoxymagnesium and used as a dialkoxymagnesium solution.

The compound capable of solubilizing solid dialkoxymagnesium includes at least one compound selected from the group consisting of alcohols, ethers, and esters. Alcohols such as ethanol, propanol, butanol, and 2-ethylhexanol are preferred, with 2-ethylhexanol being particularly preferred.
On the other hand, examples of the medium that does not have the ability to solubilize solid dialkoxymagnesium include one or more solvents selected from saturated hydrocarbon solvents and unsaturated hydrocarbon solvents that do not dissolve dialkoxymagnesium.

In the solid catalyst component for olefin polymerization according to the present invention, the tetravalent titanium halogen compound, which is a raw material component serving as a supply source of titanium and halogen, is not particularly limited, but may be represented by the following general formula (3):
Ti(OR ⁶ ) _r X _4-r (3)
(wherein ^R6 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).

In the above general formula (3), r is 0≦r≦3, and specifically, r is 0, 1, 2, or 3.

The titanium halide represented by the above general formula (3) may be one or more titanium tetrahalides selected from titanium tetrachloride, titanium tetrabromide, titanium tetraiodide, and the like.
Examples of the alkoxytitanium halide represented by the general formula (3) 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, tripropoxytitanium chloride, tri-n-butoxytitanium chloride, and the like.
As the tetravalent titanium halide compound, titanium tetrahalide is preferred, and titanium tetrachloride is more preferred.
These titanium compounds may be used alone or in combination of two or more kinds.

In the solid catalyst component for olefin polymerization according to the present invention, the succinic acid diester compound is represented by the following general formula (1):
R ¹ -O-C(=O)-CHR ² CHR ³ -C(=O)-O-R ⁴ (1)
( ^R2 and ^R3 are hydrogen atoms or alkyl groups having 1 to 4 carbon atoms and may be the same or different from each other, and ^R1 and ^R4 are linear or branched alkyl groups having 2 to 4 carbon atoms and may be the same or different from each other.)
The compound may be one or more selected from the compounds represented by the following formula:

In the compound represented by the general formula (1), R ¹ and R ⁴ are linear or branched alkyl groups having 2 to 4 carbon atoms and may be the same or different.
When R ¹ and R ⁴ are linear or branched alkyl groups having 2 to 4 carbon atoms, specific examples include an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, and an isobutyl group.
In the compound represented by the general formula (1), R ² and R ³ are a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and may be the same or different.
When R ² and R ³ are alkyl groups having 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, and an isobutyl group.

In the solid catalyst component for olefin polymerization according to the present invention, the succinic acid diester compound is not particularly limited and may be a compound represented by the general formula (1). Examples of the compound represented by the general formula (1) include, for example,
Diethyl succinate, diethyl 2,3-dimethylsuccinate, diethyl 2,3-diethylsuccinate, diethyl 2,3-di-n-propylsuccinate, diethyl 2,3-diisopropylsuccinate, diethyl 2,3-di-n-butylsuccinate, diethyl 2,3-diisobutylsuccinate;
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-dimethyl succinate, diisopropyl 2,3-diethyl succinate, diisopropyl 2,3-di-n-propyl succinate, diisopropyl 2,3-diisopropyl succinate, diisopropyl 2,3-di-n-butyl succinate, diisopropyl 2,3-diisobutyl succinate;
Di-n-butyl succinate, di-n-butyl 2,3-dimethylsuccinate, di-n-butyl 2,3-diethylsuccinate, di-n-butyl 2,3-di-n-propylsuccinate, di-n-butyl 2,3-diisopropylsuccinate, di-n-butyl 2,3-di-n-butylsuccinate, di-n-butyl 2,3-diisobutylsuccinate;
Diisobutyl succinate, diisobutyl 2,3-dimethylsuccinate, diisobutyl 2,3-diethylsuccinate, diisobutyl 2,3-di-n-propylsuccinate, diisobutyl 2,3-diisopropylsuccinate, diisobutyl 2,3-di-n-butylsuccinate, diisobutyl 2,3-diisobutylsuccinate;
One or more selected from the following can be mentioned.
Among these succinic acid diesters, diethyl succinate, di-n-propyl succinate, di-n-butyl succinate, diisobutyl succinate, diethyl 2,3-di-n-propyl succinate, diethyl 2,3-diisopropyl succinate, di-n-propyl 2,3-diisopropyl succinate, di-n-propyl 2,3-diisopropyl succinate, diisopropyl 2,3-diisopropyl succinate, di-n-butyl 2,3-di-n-propyl succinate, di-n-butyl 2,3-diisopropyl succinate, diisobutyl 2,3-di-n-propyl succinate, and diisobutyl 2,3-diisopropyl succinate are preferably used.

The solid catalyst component for olefin polymerization according to the present invention contains a succinic acid diester compound as an essential internal electron donor compound, but may further contain other internal electron donor compounds (hereinafter, appropriately referred to as "other internal electron donor compounds") as internal electron donor compounds other than the succinic acid diester compound.

Such other internal electron donor compounds include one or more selected from carbonates, acid halides, acid amides, nitriles, acid anhydrides, diether compounds, and carboxylic acid esters.

Specific examples of such other internal electron donor compounds include one or more compounds 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; dialkyl malonic acid diesters such as dimethyl diisobutylmalonate and diethyl diisobutylmalonate; cycloalkane dicarboxylic 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.

On the other hand, the solid catalyst component for olefin polymerization according to the present invention suitably has a phthalate ester content of 0.2 mass% or less (0.0 to 0.2 mass%), more suitably 0.1 mass% or less (0.0 to 0.1 mass%), and even more suitably 0.0 mass% (substantially containing no phthalate ester (below the detection limit)).

In the solid catalyst component for olefin polymerization according to the present invention, the content of the succinic acid diester compound in the total amount of components is 13.0% by mass or more, preferably 14.0% by mass or more, more preferably 15.0% by mass or more, when converted into solid content. In addition, in the solid catalyst component for olefin polymerization according to the present invention, the upper limit of the content of the succinic acid diester compound in the total amount of components is not particularly limited, but the content of the succinic acid diester compound in the total amount of components is preferably 22.0% by mass or less, more preferably 21.0% by mass or less, when converted into solid content. By having the content of the succinic acid diester compound in the total amount of components in terms of solid content within the above range, when subjected to polymerization of olefins, an olefin polymer having excellent fluidity and high rigidity can be easily produced.

In the solid catalyst component for olefin polymerization according to the present invention, the content of titanium atoms in the total amount of components, calculated as solid content, is 3.0 to 6.0 mass%, preferably 3.5 to 6.0 mass%, and more preferably 4.0 to 6.0 mass%. By having the content of titanium atoms in the total amount of components, calculated as solid content, within the above range, when subjected to the polymerization of olefins, it is possible to easily produce an olefin polymer that has excellent fluidity and high rigidity.

In the solid catalyst component for olefin polymerization according to the present invention, the molar ratio (S/T) represented by the molar amount (S) of the succinic acid diester compound in the total amount of components relative to the molar amount (T) of titanium in the total amount of components is 0.50 to 0.72, preferably 0.55 to 0.71, and more preferably 0.57 to 0.70. By having the molar ratio (S/T) in the above range, it is possible to easily produce an olefin polymer that has excellent fluidity and high rigidity when subjected to olefin polymerization, and the ratio (η ratio) of the complex viscosity η* at an angular frequency of 0.01 radian/sec to the complex viscosity η* at an angular frequency of 100 radian/sec in dynamic viscoelasticity measurement can be controlled within a predetermined range.

Conventionally, succinic acid diester compounds are expensive when used as an internal electron donor compound in a solid catalyst component for olefin polymerization, and it has been considered that they are difficult to improve the stereoregularity of the resulting olefin polymer when used in the polymerization of olefins. For this reason, attempts have not been made to use them as an internal electron donor compound in a solid catalyst component for olefin polymerization, and to incorporate them in large amounts. However, according to the studies of the present inventors, it has been found, quite unexpectedly, that by increasing the content of succinic acid diester compounds in a solid catalyst component for olefin polymerization to the above-mentioned specified amount, by making the content of titanium atoms to the above-mentioned specified amount, and by making the molar ratio represented by the molar amount of succinic acid diester compounds/the molar amount of titanium to the above-mentioned specified value, and thus incorporating a high proportion of succinic acid diester compounds, when used in the polymerization of olefins, it is possible to produce olefin polymers with higher rigidity than ever before while maintaining a practically useful fluidity, and further by improving the copolymerization performance of a solid catalyst for olefin polymerization, and thus the present invention has been completed.

In other words, the solid catalyst component for olefin polymerization according to the present invention has the above-mentioned predetermined amounts of succinic acid diester compound content and titanium atom content, and the molar ratio (S/T) represented by the molar amount (S) of succinic acid diester compound content to the molar amount (T) of titanium content is the above-mentioned predetermined value, so that the olefin polymer obtained using the solid catalyst component can be controlled within a predetermined range in (a) melt flow rate, (b) flexural modulus, and (c) the ratio (η ratio) of complex viscosity η* at an angular frequency of 0.01 radian/sec to complex viscosity η* at an angular frequency of 100 radian/sec in dynamic viscoelasticity measurement. This makes it possible to obtain polypropylene that has both high melt flowability at a melt flow rate (MFR) of 150 to 200 g/10 min and high rigidity at a flexural modulus (FM) of 1700 to 2000 MPa, and further improves the copolymerization performance of the solid catalyst for olefin polymerization.

The solid catalyst component for olefin polymerization in the present invention may contain polysiloxane.

Since the solid catalyst component for olefin polymerization in the present invention contains a polysiloxane, when olefins are polymerized, the stereoregularity or crystallinity of the resulting polymer can be easily improved, and further, the amount of fine powder in the produced polymer can be easily reduced.
Polysiloxane is a polymer having a siloxane bond (-Si-O- bond) in the main chain, and is also called silicone oil. It is a linear, partially hydrogenated, cyclic or modified polysiloxane that is liquid or viscous at room temperature and has a viscosity at 25°C of 0.02 to 100.00 cm ² /s (2 to 10,000 centistokes), more preferably 0.03 to 5.00 cm ² /s (3 to 500 centistokes).

Examples of linear polysiloxanes include dimethylpolysiloxane and methylphenylpolysiloxane, examples of partially hydrogenated polysiloxanes include methylhydrogenpolysiloxane with a hydrogenation rate of 10 to 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.

The solid catalyst component for olefin polymerization according to the present invention is preferably prepared by contacting the above-mentioned dialkoxymagnesium, titanium halide compound and succinic acid diester compound in the presence of an inert organic solvent.

In the present invention, the inert organic solvent is preferably one which dissolves the titanium halide compound but does not dissolve the dialkoxymagnesium, and specific examples thereof include one or more 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 ortho-dichlorobenzene, methylene chloride, 1,2-dichlorobenzene, carbon tetrachloride, and dichloroethane.
As the inert organic solvent, a saturated hydrocarbon compound or an aromatic hydrocarbon compound having a boiling point of about 50 to 200° C. and being liquid at room temperature is preferably used. Among them, 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 particularly preferred.

In the solid catalyst component for olefin polymerization according to the present invention, magnesium, titanium, halogen, and succinic acid diester compound can each be contained in a desired amount, so long as the content of the succinic acid diester compound described above and the molar ratio represented by the content (molar amount) of the succinic acid diester compound described above/the content (molar amount) of titanium satisfy the above-mentioned regulations.

The solid catalyst component for olefin polymerization according to the present invention preferably contains titanium in an amount of 3.0 to 6.0 mass %, more preferably 3.5 to 6.0 mass %, and even more preferably 4.0 to 6.0 mass %, calculated as atomic weight.
The solid catalyst component for olefin polymerization according to the present invention preferably contains magnesium in an amount, calculated as atomic weight, of 15.0 to 25.0 mass %, more preferably 16.0 to 23.0 mass %, even more preferably 17.0 to 22.0 mass %, and still more preferably 18.0 to 21.0 mass %.
The solid catalyst component for olefin polymerization according to the present invention preferably contains 50.0 to 70.0 mass %, more preferably 55.0 to 68.0 mass %, further preferably 58.0 to 67.0 mass %, and even more preferably 60.0 to 66.0 mass %, of halogen, calculated in terms of atomic weight.

In this application, the titanium content in the solid catalyst component for olefin polymerization refers to the value measured in accordance with the method (oxidation-reduction titration) described in JIS 8311-1997 "Method for determining titanium in titanium ore."

In addition, in this application, the magnesium content in the solid catalyst component for olefin polymerization means a value measured by an EDTA titration method in which the solid catalyst component for olefin polymerization is dissolved in a hydrochloric acid solution and titrated with an EDTA solution.

In addition, in this application, the content of halogens contained in the solid catalyst component for olefin polymerization means a 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 prepare an aqueous solution, a predetermined amount is then taken, and the halogens are titrated with a standard silver nitrate solution.

Furthermore, in this application document, the content of the succinic acid diester compound contained in the solid catalyst component for olefin polymerization and the content of other internal electron donor compounds added as required refer to values obtained by hydrolyzing the solid catalyst component for olefin polymerization, extracting the succinic acid diester compound and other internal electron donor compounds added as required using an aromatic solvent, and measuring the solution by gas chromatography FID (Flame Ionization Detector) method.

The solid catalyst component for olefin polymerization according to the present invention can be suitably produced by the method for producing the solid catalyst component for olefin polymerization according to the present invention described below.

Next, the method for producing the solid catalyst component for olefin polymerization according to the present invention will be described.
The method for producing a solid catalyst component for olefin polymerization according to the present invention comprises the steps of:
A method for producing a solid catalyst component for olefin polymerization by contacting a dialkoxymagnesium, a titanium halogen compound, and a succinic acid diester compound with each other, comprising the steps of:
contacting the dialkoxymagnesium with the titanium halide compound multiple times;
When the dialkoxy magnesium is first contacted with a titanium halide compound, 2.0 to 5.0 moles of the titanium halide compound are used per 1.0 mole of the dialkoxy magnesium;
the total amount of titanium compounds used is 5.0 to 18.0 moles per 1.0 mole of the dialkoxymagnesium;
Furthermore, the amount of the succinic acid diester compound used is 0.100 to 0.200 mol per 1.0 mol of the dialkoxymagnesium,
adjusting the amounts of the titanium halide compound and the succinic acid diester compound used so that the molar ratio (S/T) represented by the molar amount (S) of the succinic acid diester compound to the molar amount (T) of titanium is 0.50 to 0.72, preferably 0.55 to 0.71, and more preferably 0.57 to 0.70;
The present invention is characterized by the following:

In the method for producing a solid catalyst component for olefin polymerization according to the present invention, the titanium halide compound is contacted with the dialkoxymagnesium multiple times, and when the titanium halide compound is first contacted with the dialkoxymagnesium, 2.0 to 5.0 moles of the titanium halide compound are used per 1.0 mole of the dialkoxymagnesium, preferably 2.0 to 4.7 moles of the titanium halide compound are used per 1 mole of the dialkoxymagnesium, and more preferably 2.6 to 4.7 moles of the titanium halide compound are used per 1 mole of the dialkoxymagnesium.

In the method for producing a solid catalyst component for olefin polymerization according to the present invention, by controlling the amount of titanium halide compound used relative to the dialkoxymagnesium within the above range, a solid catalyst component for olefin polymerization that has high activity with a small amount of titanium halide compound can be prepared.

In the method for producing a solid catalyst component for olefin polymerization according to the present invention, the total amount of titanium compound used is 5.0 to 18.0 moles per 1.0 mole of dialkoxymagnesium, preferably 5.0 to 15.0 moles per 1.0 mole of dialkoxymagnesium, and more preferably 5.7 to 8.0 moles per 1.0 mole of dialkoxymagnesium.

In the method for producing a solid catalyst component for olefin polymerization according to the present invention, by controlling the total amount of titanium compounds used per 1.0 mole of dialkoxymagnesium within the above range, a solid catalyst component for olefin polymerization that has high activity with a small amount of titanium halide compound can be prepared.

In the method for producing a solid catalyst component for olefin polymerization according to the present invention, the molar amount of the succinic acid diester compound used per 1.0 mole of dialkoxymagnesium is 0.100 to 0.200 moles, preferably the molar amount of the succinic acid diester compound used per 1.0 mole of dialkoxymagnesium is 0.100 to 0.180 moles, and more preferably the molar amount of the succinic acid diester compound used per 1.0 mole of dialkoxymagnesium is 0.100 to 0.160 moles.

In the method for producing a solid catalyst component for olefin polymerization according to the present invention, by controlling the amount of succinic acid diester compound used per 1.0 mole of dialkoxymagnesium within the above range, it is possible to sufficiently support the succinic acid diester compound while suppressing excessive support of the titanium halide compound on the support.

In the method for producing a solid catalyst component for olefin polymerization according to the present invention, the amounts of the titanium halide compound and the succinic acid diester compound used are adjusted so that the molar ratio (S/T) expressed as the molar amount (S) of the succinic acid diester compound to the molar amount (T) of titanium is 0.50 to 0.72, preferably 0.55 to 0.71, and more preferably 0.57 to 0.70.

More specifically, the method for producing the solid catalyst component for olefin polymerization according to the present invention includes, for example, suspending dialkoxymagnesium, a titanium halide compound, and a succinic acid diester compound in an inert hydrocarbon solvent, contacting them with each other while heating for a predetermined time, adding a titanium halide compound to the suspension obtained, contacting them with each other while heating to obtain a solid product, and washing the solid product with a hydrocarbon solvent to obtain the desired solid catalyst component for olefin polymerization.

The inert organic solvent is preferably one that is liquid at room temperature (20°C) and has a boiling point of 50 to 150°C, and more preferably an aromatic hydrocarbon compound or a saturated hydrocarbon compound that is liquid at room temperature and has a boiling point of 50 to 150°C.

Specific examples of the inert organic solvent include one or more selected from linear aliphatic hydrocarbon compounds such as hexane, heptane, and decane; branched aliphatic hydrocarbon compounds such as methylheptane; alicyclic hydrocarbon compounds such as cyclohexane, methylcyclohexane, and ethylcyclohexane; and aromatic hydrocarbon compounds such as toluene, xylene, and ethylbenzene.
Among the above inert organic solvents, aromatic hydrocarbon compounds that are liquid at room temperature and have a boiling point of 50 to 150° C. are preferred because they can improve the activity of the resulting solid catalyst component and the stereoregularity of the resulting polymer.

The heating temperature is preferably from 70 to 150°C, more preferably from 80 to 120°C, and even more preferably from 90 to 115°C.
The heating time is preferably from 30 to 240 minutes, more preferably from 60 to 180 minutes, and even more preferably from 60 to 120 minutes.

The number of times the titanium halide compound is added to the suspension is not particularly limited.
When the titanium halide compound is added to the suspension a plurality of 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.

In the above preparation method, in addition to the succinic acid diester compound, other internal electron donor compounds may be used in combination. Furthermore, the above contact may be carried out in the presence of other reaction agents such as silicon, phosphorus, aluminum, etc., or surfactants.

In the production method of the present invention, the preferred embodiment of the solid catalyst component for olefin polymerization obtained is as described in detail in the description of the solid catalyst component for olefin polymerization according to the present invention.

The method for producing a solid catalyst component for olefin polymerization according to the present invention is exemplified by the first embodiment of the method for producing a solid catalyst component for olefin polymerization according to the present invention shown below (hereinafter, also referred to as the method for producing a solid catalyst component for olefin polymerization according to the present invention (1)).

The method for producing a solid catalyst component for olefin polymerization according to the present invention (1) comprises the steps of:
a first step of adding titanium tetrachloride to a first mixed suspension obtained by mixing a dialkoxymagnesium with an inert aromatic hydrocarbon solvent in a ratio of the volume of the inert aromatic hydrocarbon solvent to the volume of titanium tetrachloride (inert aromatic hydrocarbon solvent/titanium tetrachloride) of 0.50 to 2.5, and contacting the two with each other to obtain an initial contact product-containing liquid;
a second step of adding a succinic acid diester compound to the initial contact product-containing liquid, contacting them with each other at 80 to 120° C., and then washing with an inert aromatic hydrocarbon solvent to obtain a first contact product;
a third step of mixing the first contact product with an inert aromatic hydrocarbon solvent to obtain a second mixed suspension, then mixing titanium tetrachloride therewith, bringing them into contact with each other, and then washing with an inert aromatic hydrocarbon solvent to obtain a solid catalyst component for olefin polymerization;
The present invention is characterized by having at least the following features.

In addition, in the method (1) for producing a solid catalyst component for olefin polymerization according to the present invention, after the third step, the solid catalyst component for olefin polymerization obtained by carrying out the third step can be washed with an inert organic solvent.

The first step is to add titanium tetrachloride to a first mixed suspension obtained by mixing dialkoxymagnesium with an inert aromatic hydrocarbon solvent, and bring the two into contact with each other to obtain a liquid containing the initial contact product.

The dialkoxymagnesium used in the first step is the same as the dialkoxymagnesium described above.

The inert organic solvent used in the first step is an inert aromatic hydrocarbon solvent. Examples of the inert aromatic hydrocarbon solvent include aromatic hydrocarbon compounds such as benzene, toluene, xylene, and ethylbenzene.

In the first step, dialkoxymagnesium is mixed with an inert aromatic hydrocarbon solvent to obtain a first mixed suspension, and then titanium tetrachloride is added to the resulting first mixed suspension and brought into contact with each other to obtain an initial contact product-containing liquid. In the first step, the amount of titanium tetrachloride added to the first mixed suspension is set to a ratio of the volume of the inert aromatic hydrocarbon solvent to the volume of titanium tetrachloride (inert aromatic hydrocarbon solvent/titanium tetrachloride) of 0.50 to 2.5, preferably 0.60 to 2.5. By setting the ratio of inert aromatic hydrocarbon solvent/titanium tetrachloride within the above range, a solid catalyst component for olefin polymerization that achieves high activity with a small amount of titanium halogen compound can be prepared. In the first step, 2.0 to 5.0 moles, preferably 2.0 to 4.7 moles, more preferably 2.6 to 4.7 moles of titanium tetrachloride are used per 1.0 mole of dialkoxymagnesium.

The second step is a step of adding a succinic acid diester compound, preferably a compound represented by the general formula (1), to the liquid containing the initial contact product, contacting them with each other, and then washing with an inert aromatic hydrocarbon solvent to obtain a first contact product.

The succinic acid diester compound in the second step is the same as the succinic acid diester compound described above.

In the second step, a succinic acid diester compound, preferably a compound represented by the general formula (1), is added and contacted with each other at 80 to 120°C, preferably 90 to 120°C, and then washed with an inert aromatic hydrocarbon solvent to obtain a first contact product.

In the second step, the amount of the succinic acid diester compound used is an amount such that the content of the succinic acid diester compound in the solid catalyst component for olefin polymerization obtained through the third step, calculated as solid content, is 13.0% by mass or more, preferably 14.0% by mass or more, more preferably 15.0% by mass or more, and 22.0% by mass or less, more preferably 21.0% by mass or less, and the molar ratio (S/T) expressed as the molar amount (S) of the succinic acid diester compound in the total amount of components relative to the molar amount (T) of titanium in the total amount of components is 0.50 to 0.72, preferably 0.55 to 0.71, more preferably 0.57 to 0.70.

The third step is to mix the first contact product with an inert aromatic hydrocarbon solvent to obtain a second mixed suspension, then mix with titanium tetrachloride, bring them into contact with each other, and then wash with an inert aromatic hydrocarbon solvent to obtain a solid catalyst component for olefin polymerization.

In the third step, the first contact product is first mixed with an inert aromatic hydrocarbon solvent to obtain a second mixed suspension.

In the third step, titanium tetrachloride is then mixed with the resulting second mixed suspension and brought into contact with each other.

In the third step, the amount of titanium tetrachloride used is an amount, in relation to the amount of titanium tetrachloride used in the first step, such that the titanium atom content in the total amount of components of the solid catalyst component for olefin polymerization obtained through the third step is 3.0 to 6.0 mass%, preferably 3.5 to 6.0 mass%, and more preferably 4.0 to 6.0 mass%.

In the third step, the ratio of the volume of the inert aromatic hydrocarbon solvent to the volume of titanium tetrachloride (inert aromatic hydrocarbon solvent/titanium tetrachloride) is not particularly limited, but is preferably 0 to 5.0, more preferably 0 to 3.0. By setting the ratio of inert aromatic hydrocarbon solvent/titanium tetrachloride within the above range, a solid catalyst component for olefin polymerization that achieves high activity with a small amount of titanium halogen compound can be prepared. In the third step, the amount of titanium tetrachloride used relative to 1.0 mole of dialkoxymagnesium is adjusted taking into account the amount of titanium tetrachloride used in the first step so that the total amount of titanium tetrachloride used relative to 1.0 mole of dialkoxymagnesium is 5.0 to 18.0 moles, preferably 5.0 to 15.0 moles, more preferably 5.7 to 8.0 moles.

In the third step, the contact temperature when the second mixed suspension is contacted with titanium tetrachloride is preferably 70 to 150°C, more preferably 90 to 115°C, and the contact time is preferably 30 to 120 minutes, more preferably 60 to 120 minutes.

In the third step, the resulting second contact product is then washed with an inert aromatic hydrocarbon solvent. The washing temperature for the second contact product is preferably 50 to 120°C, more preferably 80 to 110°C, and the washing time is preferably 1 to 120 minutes, more preferably 1 to 60 minutes. The inert aromatic hydrocarbon solvent used for washing in the third step is the same as the inert aromatic hydrocarbon solvent described above.

Then, the third step is carried out to obtain a solid catalyst component for olefin polymerization.

In addition, in the method (1) for producing a solid catalyst component for olefin polymerization according to the present invention, after the third step, the solid catalyst component for olefin polymerization obtained by carrying out the third step can be washed with an inert organic solvent. The washing temperature of the solid catalyst component for olefin polymerization is preferably 20 to 70°C, more preferably 40 to 60°C, and the washing time is preferably 1 to 120 minutes, more preferably 1 to 60 minutes. The inert organic solvent used for washing carried out after the third step is the same as the inert organic solvent described above.

Next, the olefin polymerization catalyst according to the present invention will be described.
The olefin polymerization catalyst according to the present invention comprises
(I) a solid catalyst component for olefin polymerization according to the present invention, and (II) a compound represented by the following general formula (2):
R ⁵ _p AlQ _3-p (2)
(wherein ^R5 is an alkyl group having 1 to 6 carbon atoms, Q is a hydrogen atom or a halogen, p is 0<p≦3, and when there are multiple ^R5s , each ^R5 may be the same or different, and when there are multiple Qs, each Q may be the same or different).
The olefin polymerization catalyst according to the present invention includes
(I) The solid catalyst component for olefin polymerization according to the present invention,
(II) The following general formula (2):
R ⁵ _p AlQ _3-p (2)
(wherein R ⁵ is an alkyl group having 1 to 6 carbon atoms, Q is a hydrogen atom or a halogen atom, p is 0<p≦3, and when there are a plurality of R ^5s , each R ⁵ may be the same or different, and when there are a plurality of Qs, each Q may be the same or different), and (III) an external electron-donating compound.

The details of the (I) solid catalyst component for olefin polymerization according to the present invention that constitutes the catalyst for olefin polymerization according to the present invention are as described above.

In the olefin polymerization catalyst according to the present invention, the organoaluminum compound (II) is represented by the following general formula (2):
R ⁵ _p AlQ _3-p (2)
(wherein R ⁵ is an alkyl group having 1 to 6 carbon atoms, Q is a hydrogen atom or a halogen atom, p is 0<p≦3, and when there are a plurality of R ^5s , each R ⁵ may be the same or different, and when there are a plurality of Qs, each Q may be the same or different.)

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

Specific examples of such (II) organoaluminum compounds include one or more selected from trialkylaluminums such as triethylaluminum, triisopropylaluminum, tri-n-butylaluminum, tri-n-hexylaluminum, and triisobutylaluminum; alkylaluminum halides such as diethylaluminum chloride and diethylaluminum bromide; and diethylaluminum hydride. Of these, one or more selected from alkylaluminum halides such as diethylaluminum chloride; trialkylaluminums such as triethylaluminum, tri-n-butylaluminum, and triisobutylaluminum; and more preferably one or more selected from triethylaluminum and triisobutylaluminum.

The external electron donor compound (III) constituting the olefin polymerization catalyst of the present invention is,
For example, the following general formula (4)
R ⁷ _r Si(NR ⁸ R ⁹ ) _s (OR ¹⁰ ) _4-(r+s) (4)
(wherein r is 0 or 1 to 2, s is 0 or 1 to 2, r+s is 0 or 1 to 4, R ⁷ , R ⁸ and R ⁹ are any group selected from a hydrogen atom or a linear or branched alkyl group having 1 to 12 carbon atoms, a substituted or unsubstituted cycloalkyl group, a phenyl group, an allyl group and an aralkyl group, which may contain a heteroatom and may be the same or different from each other. R ⁸ and R ⁹ may be bonded to form a ring, and R ⁷ , R ⁸ and R ⁹ may be the same or different. In addition, R ¹⁰ is any group selected from an alkyl group having 1 to 4 carbon atoms, a cycloalkyl group, a phenyl group, a vinyl group, an allyl group and an aralkyl group, which may contain a heteroatom.)

In the compound represented by the above general formula (4), ^R7 is any group selected from a hydrogen atom or a linear or branched alkyl group having 1 to 12 carbon atoms, a substituted or unsubstituted cycloalkyl group, a phenyl group, an allyl group, and an aralkyl group, and may contain a heteroatom.
^R7 is preferably a linear or branched alkyl group having 1 to 10 carbon atoms or a cycloalkyl group having 5 to 8 carbon atoms, and particularly preferably a linear or branched alkyl group having 1 to 8 carbon atoms or a cycloalkyl group having 5 to 8 carbon atoms.

In the compound represented by the above general formula (4), ^R8 or ^R9 is any group selected from a hydrogen atom or a linear or branched alkyl group having 1 to 12 carbon atoms, a substituted or unsubstituted cycloalkyl group, a phenyl group, an allyl group, and an aralkyl group, and may contain a heteroatom.
^R8 or ^R9 is preferably a linear or branched alkyl group having 1 to 10 carbon atoms or a cycloalkyl group having 5 to 8 carbon atoms, and particularly preferably a linear or branched alkyl group having 1 to 8 carbon atoms or a cycloalkyl group having 5 to 8 carbon atoms.
Furthermore, R ⁸ and R ⁹ may be bonded to form a ring, and in this case, (NR ⁸ R ⁹ ) forming the ring is preferably a perhydroquinolino group or a perhydroisoquinolino group.

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

In the compound represented by the above general formula (4), R ¹⁰ is any group selected from an alkyl group, a cycloalkyl group, a phenyl group, an allyl group, and an aralkyl group having 1 to 4 carbon atoms, and may contain a heteroatom.
R ¹⁰ is preferably a linear or branched alkyl group having 1 to 4 carbon atoms.

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

Specific examples of compounds represented by the above general formula (4) include one or more organosilicon compounds selected from phenylalkoxysilanes, alkylalkoxysilanes, phenylalkylalkoxysilanes, cycloalkylalkoxysilanes, cycloalkylalkylalkoxysilanes, (alkylamino)alkoxysilanes, alkyl(alkylamino)alkoxysilanes, alkyl(alkylamino)silanes, alkylaminosilanes, etc.

Particularly preferred compounds in which s is 0 in the above general formula (4) are di-n-propyldimethoxysilane, diisopropyldimethoxysilane, di-n-butyldimethoxysilane, diisobutyldimethoxysilane, di-t-butyldimethoxysilane, t-butylmethyldimethoxysilane, t-butylethyldimethoxysilane, di-n-butyldiethoxysilane, t-butyltrimethoxysilane, t-butyltriethoxysilane, dicyclohexyldimethoxysilane, dicyclohexyldiethoxysilane, cyclohexylmethyldimethoxysilane, cyclohexylmethyldiethoxysilane, cyclohexylethyldimethoxysilane, The examples of the organic silicon compounds include one or more organic silicon compounds selected from the group consisting of cyclohexyl ethyl diethoxysilane, dicyclopentyl dimethoxysilane, dicyclopentyl diethoxysilane, cyclopentyl methyl dimethoxysilane, cyclopentyl methyl diethoxysilane, cyclopentyl ethyl diethoxysilane, cyclohexyl cyclopentyl dimethoxysilane, cyclohexyl cyclopentyl diethoxysilane, 3-methylcyclohexyl cyclopentyl dimethoxysilane, 4-methylcyclohexyl cyclopentyl dimethoxysilane, and 3,5-dimethylcyclohexyl cyclopentyl dimethoxysilane.

Examples of compounds in which s in the above general formula (4) is 1 or 2 include one or more organosilicon compounds selected from di(alkylamino)dialkoxysilanes, (alkylamino)(cycloalkylamino)dialkoxysilanes, (alkylamino)(alkyl)dialkoxysilanes, di(cycloalkylamino)dialkoxysilanes, vinyl(alkylamino)dialkoxysilanes, allyl(alkylamino)dialkoxysilanes, (alkoxyamino)trialkoxysilanes, (alkylamino)trialkoxysilanes, (cycloalkylamino)trialkoxysilanes, etc., and particularly preferred are ethyl(t-butyl) Examples of the organic silicon compounds include bis(perhydroisoquinolino)dimethoxysilane, cyclohexyl(cyclohexylamino)dimethoxysilane, ethyl(t-butylamino)dimethoxysilane, bis(cyclohexylamino)dimethoxysilane, bis(perhydroisoquinolino)dimethoxysilane, bis(perhydroquinolino)dimethoxysilane, ethyl(isoquinolino)dimethoxysilane, diethylaminotrimethoxysilane, and diethylaminotriethoxysilane. Among these, the organic silicon compounds are at least one selected from bis(perhydroisoquinolino)dimethoxysilane, diethylaminotrimethoxysilane, and diethylaminotriethoxysilane.

In addition, two or more compounds represented by the above general formula (4) may be used in combination.

The catalyst for olefin polymerization according to the present invention is a catalyst containing (I) the solid catalyst component for olefin polymerization according to the present invention, and (II) an organoaluminum compound represented by general formula (2), or a catalyst containing (I) the solid catalyst component for olefin polymerization according to the present invention, (II) an organoaluminum compound represented by general formula (2), and (III) an external electron-donor compound, i.e., a contact product thereof.
The catalyst for olefin polymerization according to the present invention may be prepared by contacting (I) the solid catalyst component for olefin polymerization according to the present invention with (II) an organoaluminum compound represented by general formula (2), or further with (III) an external electron donor compound, in the absence of olefins, or may be prepared by contacting them in the presence of olefins (in the polymerization system), as described below.

In the olefin polymerization catalyst according to the present invention, the content ratio of each component is arbitrary as long as it does not affect the effects of the present invention, and is not particularly limited. However, usually, it is preferable that the (II) organoaluminum compound is contained in an amount of 1 to 2000 moles, and more preferably 50 to 1000 moles, per mole of titanium atom in the (I) solid catalyst component for olefin polymerization. In addition, the olefin polymerization catalyst according to the present invention preferably contains 0.002 to 10.000 moles, more preferably 0.010 to 2.000 moles, and even more preferably 0.010 to 0.500 moles of the (III) external electron donor compound per mole of the (II) organoaluminum compound.

According to the present invention, it is possible to provide a catalyst for olefin polymerization that contains an internal electron donor compound other than phthalic acid ester and can easily produce an olefin polymer that has excellent melt flowability and high rigidity. Furthermore, according to the present invention, it is possible to provide a solid catalyst for olefin polymerization that can improve catalyst particles and copolymerization performance in addition to achieving both the above-mentioned excellent melt flowability and high rigidity.

Next, the process for producing the olefin polymer according to the present invention will be described.
The process for producing an olefin polymer according to the present invention is characterized in that olefins are polymerized in the presence of the olefin polymerization catalyst according to the present invention.

In the process for producing an olefin polymer according to the present invention, the polymerization of olefins may be homopolymerization or copolymerization.
In the method for producing an olefin polymer according to the present invention, examples of the olefin to be polymerized include one or more selected from ethylene, propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, vinylcyclohexane, and the like. Among them, one or more selected from ethylene, propylene, and 1-butene are preferred, and propylene is more preferred.
When the olefin is propylene, it may be a homopolymer of propylene or a copolymer of propylene with other α-olefins.
The olefins to be copolymerized with propylene include one or more selected from ethylene, 1-butene, 1-pentene, 4-methyl-1-pentene, vinylcyclohexane, and the like.

When the catalyst for olefin polymerization according to the present invention is prepared in the presence of olefins (within the polymerization system), the ratio of the amounts of the components used is arbitrary as long as it does not affect the effects of the present invention, and is not particularly limited. Usually, however, the above-mentioned (II) organoaluminum compound is preferably contacted in an amount of 1 to 2000 moles, more preferably 50 to 1000 moles, per mole of titanium atoms in the above-mentioned (I) solid catalyst component for olefin polymerization. Also, the above-mentioned (III) external electron donor compound is preferably contacted in an amount of 0.002 to 10.000 moles, more preferably 0.010 to 2.000 moles, and even more preferably 0.010 to 0.500 moles, per mole of the above-mentioned (II) organoaluminum compound.

The order of contact of the components constituting the olefin polymerization catalyst is arbitrary, but it is preferable to first charge the (II) organoaluminum compound into the polymerization system, and then, when the (III) external electron donor compound is used, charge and contact the (III) external electron donor compound, and then charge and contact the (I) solid catalyst component for olefin polymerization.

The process for producing an olefin polymer according to the present invention may be carried out in the presence or absence of an organic solvent.
In addition, olefin monomers such as propylene can be used in either a gaseous or liquid state. The polymerization temperature is preferably 200° C. or less, more preferably 100° C. or less, and the polymerization pressure is preferably 10 MPa or less, more preferably 5 MPa or less. In addition, the polymerization of olefins can be performed by either a continuous polymerization method or a batch polymerization method. Furthermore, the polymerization reaction may be performed in one stage or in two or more stages.

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

In carrying out the prepolymerization, the order of contacting each component constituting the above-mentioned catalyst for olefin polymerization with the monomer (olefin) is arbitrary, but it is preferable to first charge (II) an organoaluminum compound into a prepolymerization system set in an inert gas atmosphere or an olefin gas atmosphere, then charge (I) the solid catalyst component for olefin polymerization according to the present invention, and after contacting them, contact them with an olefin such as propylene alone or a mixture of an olefin such as propylene and one or more other olefins.
In the above prepolymerization, when an external electron-donor compound (III) is further charged into the prepolymerization system, it is preferred that the organoaluminum compound (II) is first charged into the prepolymerization system set in an inert gas atmosphere or an olefin gas atmosphere, and then the external electron-donor compound (III) is charged and contacted with the solid catalyst component for olefin polymerization according to the present invention (I), and then an olefin such as propylene alone or a mixture of an olefin such as propylene and one or more other olefins is contacted with the solid catalyst component.

In the method for producing an olefin polymer according to the present invention, the polymerization method may be a slurry polymerization method using a solvent of an inert hydrocarbon compound such as cyclohexane or heptane, a bulk polymerization method using a solvent such as liquefied propylene, or a gas phase polymerization method that does not substantially use a solvent, with the bulk polymerization method or the gas phase polymerization method being preferred.

When copolymerizing propylene with other α-olefin monomers, typical methods are random copolymerization, in which propylene and a small amount of ethylene are used as comonomers and polymerized in one stage, and so-called propylene-ethylene block copolymerization, in which propylene is homopolymerized in the first stage (first polymerization tank) and then copolymerized with propylene and other α-olefins such as ethylene in the second stage (second polymerization tank) or in multiple stages (multistage polymerization tanks). Block copolymerization of propylene with other α-olefins is preferred.

A block copolymer obtained by block copolymerization is a polymer containing segments in which the composition of two or more monomers changes continuously, and refers to a form in which two or more types of polymer chains (segments) with different primary structures of the polymer, such as monomer type, comonomer type, comonomer composition, comonomer content, comonomer sequence, and stereoregularity, are connected in one molecular chain.

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

Specifically, the block copolymerization reaction of propylene with other α-olefins is preferably carried out in a first step by adjusting the polymerization temperature and time so that the proportion of the polypropylene part (in the finally obtained copolymer) is 20 to 90 mass %, and then in a second step by introducing propylene and ethylene or other α-olefin and polymerizing so that the proportion of the rubber part, such as ethylene-propylene rubber (EPR), is 10 to 80 mass % (in the finally obtained copolymer).
The polymerization temperature in both the first and second stages is preferably 200° C. or less, more preferably 100° C. or less, even more preferably 65° C. to 80° C., and still more preferably 75° C. to 80° C., and the polymerization pressure is preferably 10 MPa or less, more preferably 6 MPa or less, and even more preferably 5 MPa or less.
In the copolymerization reaction, either a continuous polymerization method or a batch polymerization method can be used, and the polymerization reaction may be carried out in one stage or in two or more stages.
The polymerization time (residence time in the reactor) is preferably from 1 minute to 5 hours in each of the previous and subsequent polymerization stages, or in the case of continuous polymerization.
Examples of the polymerization method include a slurry polymerization method using a solvent of an inert hydrocarbon compound such as cyclohexane or heptane, a bulk polymerization method using a solvent such as liquefied propylene, and a gas phase polymerization method which does not substantially use a solvent, and the bulk polymerization method or the gas phase polymerization method is preferred.

In particular, ethylene-propylene block copolymers contain EPR components (copolymer components of ethylene and propylene), and when the EPR components seep out onto the surface of polymer particles, the particles become sticky (adhesive) and their fluidity deteriorates. Since the deterioration of particle fluidity in polymer production equipment reduces the operability of the plant, it is desirable to select a polymer production method that can suppress the seepage of EPR components onto the particle surface.

The present invention provides a method for easily producing olefin polymers that have excellent melt flow properties and high rigidity.

Next, the olefin polymer according to the present invention will be described.
The olefin polymer according to the present invention is
(a) a melt flow rate of 150 to 200 g/10 min;
(b) a flexural modulus of 1700 to 2000 MPa;
(c) In a dynamic viscoelasticity measurement, the ratio (η ratio) of the complex viscosity η* at 190°C and an angular frequency of 0.01 radian/sec to the complex viscosity η* at 190°C and an angular frequency of 100 radian/sec is 4.0 to 6.0;
It is characterized by the above.

In the olefin polymer of the present invention, the melt flow rate (MFR), which indicates the melt flowability of the olefin polymer, is 150 to 200 g/10 min, preferably 160 to 200 g/10 min.

In the olefin polymer of the present invention, the melt flow rate (MFR) is within the above range, so that it can easily exhibit sufficient moldability for practical use.

In this application, melt flow rate (MFR) refers to a value measured based on ASTM D 1238 and JIS K 7210.

The olefin polymer according to the present invention has a flexural modulus (FM) of 1700 to 2000 MPa, preferably 1800 to 2000 MPa, and more preferably 1900 to 2000 MPa.

The olefin polymer of the present invention has a flexural modulus (FM) within the above range, which allows it to have excellent moldability and exhibit high rigidity.

In this application, the flexural modulus (FM) of olefin polymers refers to the value (unit: MPa) measured at a measurement ambient temperature of 23°C according to JIS K7171 using injection-molded test pieces with a thickness of 4.0 mm, width of 10.0 mm, and length of 80.0 mm, prepared 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.

The olefin polymer of the present invention satisfies the above-mentioned melt flow rate and flexural modulus requirements, and therefore has sufficient fluidity for practical use, and therefore has excellent moldability and can easily exhibit excellent rigidity.

In the olefin polymer according to the present invention, in a dynamic viscoelasticity measurement of the olefin polymer, the ratio (η ratio) of the complex viscosity η* at 190°C and an angular frequency of 0.01 radian/sec to the complex viscosity η* at 190°C and an angular frequency of 100 radian/sec is 4.0 to 6.0, preferably 4.2 to 6.0, and more preferably 4.5 to 6.0.

In the olefin polymer according to the present invention, the ratio of the complex viscosity η* at 190°C and an angular frequency of 0.01 radian/sec to the complex viscosity η* at 190°C and an angular frequency of 100 radian/sec (complex viscosity η* at an angular frequency of 0.01 radian/sec/complex viscosity η* at an angular frequency of 100 radian/sec) (complex elasticity ratio (η ratio)) in the dynamic viscoelasticity measurement of the olefin polymer is within the above range, so that the polymer has excellent moldability and can exhibit high rigidity.

In the olefin polymer according to the present invention, the complex viscosity η* that defines the complex viscoelastic ratio (η ratio) of the olefin polymer is measured using a rheometer (MCR302 manufactured by Anton Paar).
The olefin polymer is compression molded in a press at 210° C. for 5 minutes while taking care not to trap air bubbles, to obtain a disk-shaped measurement sample having a thickness of 2 mm and a diameter of 25 mm.
The measurement is carried out using a rheometer (MCR302) manufactured by Anton Paar.
Using parallel circular plates with a diameter of 25 mm arranged with a gap of 1 mm, and with the gap filled with a measurement sample, the complex viscosity η* is measured at a measurement temperature of 190° C. and in a frequency range from 0.01 radian/sec to 100 radian/sec.
The complex viscoelastic ratio (η ratio) is calculated as the ratio of the complex viscosity η* at an angular frequency of 0.01 radian/second under temperature conditions of 190°C to the complex viscosity η* at an angular frequency of 100 radians/second under temperature conditions of 190°C (complex viscosity η* at an angular frequency of 0.01 radian/second under temperature conditions of 190°C/complex viscosity η* at an angular frequency of 100 radian/second under temperature conditions of 190°C).

When the olefin polymer according to the present invention is molded into an injection molded plate, the proportion of the oriented layer in the cross section of the injection molded plate is preferably 20% or more, more preferably 20 to 50%, and even more preferably 25 to 40%.

When the olefin polymer according to the present invention is molded into an injection molded plate, the proportion of the oriented layer in the cross section of the injection molded plate satisfies the above-mentioned regulations, so that the thickness of the oriented layer becomes thick, and it is easy to provide a plate with excellent flexural modulus.

In the present application, the proportion of an oriented layer in a cross section of an injection-molded plate of an olefin polymer means a value measured by the following method.
1. Formation of Molded Article According to JIS K 7152-1 and JIS K 6921-2, an olefin polymer is injection molded under the following conditions to obtain a molded article having the external shape shown in FIG.
Apparatus: NEX-III-3EG manufactured by Nissei Plastic Industrial Co., Ltd. Type of test piece: Multipurpose test piece type A1 according to JIS K 7139
Resin melting temperature: 200°C
Mold temperature: 40°C
Injection speed: 180 mm/sec. Dwell pressure: 50 MPa-40 sec. 2. Preparation of measurement sample (thin piece for observation under polarizing microscope) (1) As shown in FIG. 1, the obtained molded product is cut in a direction perpendicular to the resin traveling direction MD at a position c1 about 2 cm long in the resin traveling direction MD from the gate G of the molded product obtained, to obtain a cut product S1 shown in FIG. 2(a).
(2) As shown in FIG. 2(a), the cut product S1 obtained in (1) is cut in the center (position c2) parallel to the resin traveling direction MD to obtain a cut product S2 shown in FIG. 2(b).
(3) As shown in FIG. 2(b), using a rotary microtome device (RX-860 manufactured by Yamato Koki Kogyo Co., Ltd.), the cut piece S2 is cut out at position c3 parallel to the resin traveling direction MD to a thickness of 30 μm to obtain a thin-section measurement sample S3 shown in FIG. 2(c).
(4) Figure 2(d) is a schematic diagram showing the obtained flake-shaped measurement sample S3, in which the left side of Figure 2(d) is a side view of the flake-shaped measurement sample S3 corresponding to Figure 2(c), and the right side of Figure 2(d) is a front view of the flake-shaped measurement sample S4.
3. Polarizing Microscope Observation FIG. 3 is an enlarged front view of the thin-section measurement sample S3 shown on the right side of FIG.
The measurement sample S3 is observed with a polarizing microscope (EPCLIPSE LV-100NDA manufactured by NIKON CORPORATION) to identify the core layer c and the orientation layers h1 and h2. The thickness of the core layer is Tc, the thickness of the orientation layers is Th1 and Th2, and the ratio F (%) of the orientation layer to the thickness of the molded layer is calculated using the following formula (5).
F (%) = ((Th1+Th2)/(Th1+Tc+Th2))×100 (5)
The thickness Tc of the core layer and the thicknesses Th1 and Th2 of the alignment layers are calculated by arithmetic average values obtained by measuring the thickness of the core layer c and the thickness of the alignment layers h1 and h2 at any 10 points.

When the olefin polymer according to the present invention is a crystalline polymer, when the molten polymer is poured into a mold for injection molding, the polymer flows into the mold under high shear stress and is cooled, so that oriented crystallization occurs near the surface of the resulting injection molded product. When this injection molded product is thinly sliced using a microtome or the like and the cross section is observed under a polarizing microscope, it is possible to confirm that the highly birefringent oriented layer formed near the surface and the internal core layer are clearly separated, and therefore it is possible to easily determine the thickness Tc of the core layer and the thicknesses Th1 and Th2 of the oriented layers.

The olefin polymer of the present invention can be easily produced by the method for producing the olefin polymer of the present invention.

The present invention provides an olefin polymer that has excellent melt flowability and high rigidity.

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

Example 1
1. Synthesis of Solid Catalyst Component A solid catalyst component for olefin polymerization was prepared by the following method using diethyl diisopropylsuccinate, which is a succinic acid diester compound, as an internal electron donor compound.
(i) Into a 500 mL flask equipped with a stirrer and purged with nitrogen gas, 20 g (174.8 mmol) of diethoxymagnesium and 100.0 mL of toluene were placed to form a suspension.
(ii) Next, 50.0 mL (456 mmol) of titanium tetrachloride was added to obtain an initial contact product-containing liquid.
(iii) The initial contact product-containing liquid was heated, and 5.2 mL (19.2 mmol) of diethyl diisopropylsuccinate was added at 90° C. during the temperature increase, and the temperature was further increased to 100° C., and the reaction was carried out for 90 minutes while maintaining the temperature. After the reaction was completed, the supernatant was removed, and the first contact product, which was the reaction product, was washed four times with 105 mL of toluene at 90° C.
(iv) Next, 60 mL (547 mmol) of titanium tetrachloride was added to the first contact product, and the mixture was heated to 115° C. and reacted for 60 minutes. After completion of the reaction, the supernatant was removed, and the second contact product, which was the reaction product, was washed twice with 105 mL of toluene at 90° C. to obtain a final contact product.
Next, the resulting final contact product was washed six times with 100 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 catalyst component thus obtained was separated into solid and liquid, and the titanium content and the succinic acid diester compound content in the solid were measured to be 5.4% by mass and 17.9% by mass, respectively. The molar ratio of the succinic acid diester compound content/titanium content was 0.62.
The properties of the resulting solid catalyst component are shown in Table 1.

The titanium content in the solid catalyst component, the content of diisopropyl succinate, which corresponds to the succinic acid diester compound, an internal electron donor compound, and physical properties were measured using the following methods.

<Titanium content in solid catalyst component>
The titanium content in the solid catalyst component was measured based on the method of JIS 8311-1997.

<Content of internal electron donor compound>
The content of the internal electron donor compound was determined by measurement under the following conditions using gas chromatography (GC-14B, manufactured by Shimadzu Corporation). The number of moles of the internal electron donor compound was determined from the results of gas chromatography measurement using a calibration curve previously measured at known concentrations.
(Measurement conditions)
Column: Packed column (φ2.6×2.1 m, Silicone SE-30 10%, Chromosorb WAW DMCS 80/100, manufactured by GL Sciences, Inc.)
Detector: FID (Flame Ionization Detector)
Carrier gas: helium, flow rate 40 mL/min Measurement temperature: vaporizer 280°C, column 225°C, detector 280°C

2. Formation of polymerization catalyst and polymerization reaction In a 2.0 L capacity autoclave equipped with a stirrer and substituted with nitrogen gas, 1.32 mmol of triethylaluminum, 0.131 mmol of diisopropyldimethoxysilane (DIPDMSi) and 0.00264 mmol of the above solid catalyst component in terms of titanium atom were charged to form a polymerization catalyst. Then, 6.0 L of hydrogen gas and 1.4 L of liquefied propylene were charged, and preliminary polymerization was carried out at 20°C for 5 minutes, followed by heating and polymerization reaction at 70°C for 1 hour.
The polymerization activity per 1 g of the solid catalyst component, the melt flowability of the polymer (melt flow rate (MFR)), the proportion of p-xylene solubles in the polymer (XS), the flexural modulus of the polymer (FM), the proportion of oriented layers in the cross section of the injection-molded plate made of the obtained polymer, and the molecular weight distributions of the polymer (Mw/Mn and Mz/Mw) were measured by the following methods. The results are shown in Table 2.

<Polymerization activity per gram of solid catalyst component>
The polymerization activity per 1 g of the solid catalyst component was calculated according to the following formula (6).
Polymerization activity (g/g-cat)=mass of polymer (g)/mass of solid catalyst component (g) (6)

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

<Proportion of p-xylene solubles in polymer (XS)>
In a flask equipped with a stirrer, 4.0 g of a polymer (polypropylene) and 200 mL of p-xylene were charged. Next, the external temperature was set to about 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. Thereafter, the solution was cooled to a liquid temperature of 23° C. over 1 hour, and insoluble and soluble components were separated by filtration. The solution of the soluble components was collected, and p-xylene was distilled off by heating and drying under reduced pressure. The weight of the resulting residue was determined, and the relative proportion (mass%) to the produced polymer (polypropylene) was calculated to obtain the xylene-soluble component (XS).

<Flexural modulus (FM) of polymer>
Using NEX30III3EG manufactured by Nissei Plastic Industrial Co., Ltd., injection-molded test pieces having a thickness of 4.0 mm, a width of 10.0 mm and a length of 80 mm were prepared under conditions of a molding temperature of 200°C and a mold temperature of 40°C, and measurements were performed at an atmospheric temperature of 23°C based on JIS K7171.

<Proportion of Oriented Layer in Cross Section of Injection-Molded Polymer Plate>
1. Formation of Molded Articles Molded articles having the external shape shown in FIG. 1 were obtained by injection molding an olefin polymer under the following conditions in accordance with JIS K 7152-1 and JIS K 6921-2.
Apparatus: NEX-III-3EG manufactured by Nissei Plastic Industrial Co., Ltd. Type of test piece: Multipurpose test piece type A1 according to JIS K 7139
Resin melting temperature: 200°C
Mold temperature: 40°C
Injection speed: 180 mm/sec. Dwell pressure: 50 MPa-40 sec. 2. Preparation of measurement sample (thin piece for observation under polarizing microscope) (1) As shown in FIG. 1, the obtained molded product was cut in a direction perpendicular to the resin traveling direction MD at a position c1 about 2 cm long in the resin traveling direction MD from the gate G of the molded product obtained, to obtain a cut product S1 shown in FIG. 2(a).
(2) As shown in FIG. 2(a), the cut product S1 obtained in (1) was cut parallel to the resin traveling direction MD at the center (position c2) to obtain the cut product S2 shown in FIG. 2(b).
(3) As shown in FIG. 2(b), using a rotary microtome device (RX-860 manufactured by Yamato Koki Kogyo Co., Ltd.), the cut piece S2 was cut out at position c3 parallel to the resin traveling direction MD to a thickness of 30 μm to obtain a thin-section measurement sample S3 shown in FIG. 2(c).
(4) Figure 2(d) is a schematic diagram showing the obtained flake-shaped measurement sample S3, in which the left side of Figure 2(d) is a side view of the flake-shaped measurement sample S3 corresponding to Figure 2(c), and the right side of Figure 2(d) is a front view of the flake-shaped measurement sample S4.
3. Polarizing Microscope Observation FIG. 3 is an enlarged front view of the thin-section measurement sample S3 shown in the right diagram of FIG.
The above measurement sample S3 was observed with a polarizing microscope (EPCLIPSE LV-100NDA manufactured by NIKON CORPORATION) to identify the core layer c and the orientation layers h1 and h2. The thickness of the core layer was Tc, the thickness of the orientation layers was Th1 and Th2, and the ratio F (%) of the orientation layer to the thickness of the molded layer was calculated using the following formula (5).
F (%) = ((Th1+Th2)/(Th1+Tc+Th2))×100 (5)
The thickness Tc of the core layer and the thicknesses Th1 and Th2 of the orientation layers were calculated by measuring the thickness of the core layer c and the thicknesses of the orientation layers h1 and h2 at any 10 points of the measurement sample S3 and using the arithmetic average values.

<Molecular Weight Distribution of Polymer>
The molecular weight distribution of the polymer was evaluated by the ratio Mw/Mn of the mass average molecular weight Mw to the number average molecular weight Mn and the ratio Mz/Mw of the Z average molecular weight Mz to the mass average molecular weight Mw, which were measured by gel permeation chromatography (GPC) (GPCV2000 manufactured by Waters) under the following conditions.
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: 0.5 mL
Flow rate: 1.0mL/min

<Complex viscoelastic ratio (complex viscosity η* at an angular frequency of 0.01 radian/sec under a temperature condition of 190° C./complex viscosity η* at an angular frequency of 100 radian/sec under a temperature condition of 190° C.)
The complex viscosity η*, which defines the complex viscoelastic ratio of the olefin polymer, was measured using a rheometer (MCR302, manufactured by Anton Paar).
The olefin polymer was compression molded in a press at 210° C. for 5 minutes while taking care not to trap air bubbles, to obtain a disk-shaped measurement sample having a thickness of 2 mm and a diameter of 25 mm.
The measurements were carried out using a rheometer (MCR302) manufactured by Anton Paar.
Using parallel circular plates with a diameter of 25 mm arranged with a gap of 1 mm, and with the gap filled 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 radian/sec to 100 radian/sec.
The complex viscoelastic ratio was calculated as the ratio of the complex viscosity η* at an angular frequency of 0.01 radian/sec under a temperature condition of 190°C to the complex viscosity η* at an angular frequency of 100 radians/sec under a temperature condition of 190°C (complex viscosity η* at an angular frequency of 0.01 radian/sec under a temperature condition of 190°C/complex viscosity η* at an angular frequency of 100 radian/sec under a temperature condition of 190°C) (referred to as η ratio in Table 2).

(Examples 2 to 6 and Comparative Examples 1 to 5)
The same procedure as in Example 1 was carried out except that the conditions were as shown in Table 1. The results are shown in Tables 1 and 2.

In Table 1, "solvent/ _TiCl4 " is the volume ratio of the inert aromatic hydrocarbon solvent to titanium tetrachloride. "ID/M" is the molar ratio of the internal electron donor compound to the dialkoxymagnesium. "Molar ratio (S/T)" is the molar ratio represented by the molar amount (S) of the succinic acid diester compound contained in the total amount of ingredients relative to the molar amount (T) of titanium contained in the total amount of ingredients.

(Example 7)
<Preparation of ethylene-propylene copolymerization catalyst>
An ethylene-propylene copolymerization catalyst was prepared by charging 2.4 mmol of triethylaluminum, 0.24 mmol of dicyclopentylbis(ethylamino)silane, and 0.0034 mmol of the solid catalyst component obtained in Example 1, calculated as titanium atom, into a 2.0 L autoclave equipped with a stirrer and purged with nitrogen gas.

<Ethylene-propylene copolymerization>
Into an autoclave equipped with a stirrer containing the ethylene-propylene copolymerization catalyst prepared above, 15 moles (1.2 liters) of liquefied propylene and 0.20 MPa (partial pressure) of hydrogen gas were charged, and preliminary polymerization was carried out at 20°C for 5 minutes, followed by heating and carrying out a first-stage propylene homopolymerization reaction (homostage polymerization) at 70°C for 45 minutes. The pressure was then returned to normal pressure, and the inside of the autoclave (reactor) was replaced with nitrogen, after which the autoclave was weighed and the tare weight of the autoclave was subtracted to calculate the polymerization activity (homoactivity, g/g-cat) of the homostage (first stage).
Next, ethylene/propylene were charged into the autoclave (reactor) so that the molar ratio was 0.42/0.58, respectively, and then the temperature was raised to 70° C., and ethylene/propylene/hydrogen were introduced so that the gas supply rates per minute (liters/min) were 1.7/2.3/0.086, respectively, while reacting under conditions of 1.2 MPa, 70° C., and 60 minutes, to obtain an ethylene-propylene copolymer.
With respect to the obtained ethylene-propylene copolymer, the copolymerization (ICP) activity (g/g-cat), the melt flow property of the polymer (MFR, g/10 min), the block rate (mass%), and the EPR content (mass%) were measured by the following methods.

<Copolymerization (ICP) activity (g/g-cat)>
The copolymerization (ICP) activity during the formation of the ethylene-propylene block copolymer was calculated by the following formula (7).
Copolymerization (ICP) activity (g/g-cat)=((I(g)-G(g))/mass (g) of solid catalyst component contained in olefin polymerization catalyst)/reaction time (hours) (7)
Here, I(g) is the mass (g) of the autoclave after the copolymerization reaction is completed, and G(g) is the mass (g) of the autoclave after the homo-PP polymerization reaction is completed and the unreacted monomers are removed.

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

<Block rate (mass%)>
The block ratio of the ethylene-propylene copolymer was calculated by the following formula (8).
Block rate (mass%)={(I(g)−G(g))/(I(g)−F(g))}×100 (8)
Here, I is the mass (g) of the autoclave after the copolymerization reaction is completed, G is the mass (g) of the autoclave after the homopolypropylene polymerization is completed and unreacted monomers are removed, and F is the mass (g) of the autoclave.

<EPR content>
In a 1-liter flask equipped with a stirrer and a cooling tube, about 2.5 g of the copolymer, 8 mg of 2,6-di-t-butyl-p-cresol, and 250 mL of p-xylene were added, and the mixture was stirred at boiling point until the copolymer was completely dissolved. Next, the flask was cooled to room temperature, left for 15 hours, and solid matter was precipitated. The mixture was then separated into a solid matter and a liquid phase portion using a centrifuge. The separated solid matter was then placed in a beaker, 500 mL of acetone was poured in, and the mixture was stirred at room temperature for 15 hours. The solid matter was then filtered and dried, and the dry mass was measured (this mass was designated as B(g)). The same operation was also performed on the separated liquid phase portion, and the solid matter was precipitated and then dried, and its dry mass was measured (this mass was designated as C(g)). The ethylene-propylene rubber component (EPR) content in the copolymer was calculated using the following formula (9).
EPR content (mass%) = [C (g) / {B (g) + C (g)}] × 100 (9)
The results are shown in Table 3.

(Comparative Example 6)
<Preparation of ethylene-propylene copolymerization catalyst>
Except for using the solid catalyst component obtained in Comparative Example 5, the preparation of an ethylene-propylene copolymerization catalyst and the copolymerization reaction were carried out in the same manner as in Example 7. The ethylene-propylene block copolymerization activity, block ratio and EPR content were measured in the same manner as in Example 7. The results are shown in Table 3.

According to the present invention, it is possible to easily produce olefin polymers that contain an internal electron donor compound other than phthalate ester and have excellent melt flow properties and high rigidity, and it is also possible to provide a solid catalyst component for olefin polymerization that can easily produce copolymers with a practically sufficient block ratio under excellent copolymerization activity.

Claims (11)

Contains magnesium, titanium, halogens, and succinic acid diester compounds.
The content of the succinic acid diester compound in the total amount of components is 13.0% by mass or more, and the content of titanium atoms is 3.0 to 6.0% by mass, calculated as a solid content;
a molar ratio (S/T) represented by the molar amount (S) of the succinic acid diester compound in the total amount of components to the molar amount (T) of the titanium in the total amount of components is 0.50 to 0.72;
A solid catalyst component for olefin polymerization, comprising: The succinic acid diester compound is represented by the following general formula (1);
R ¹ -O-C(=O)-CHR ² CHR ³ -C(=O)-O-R ⁴ (1)
(In the formula, ^R2 and ^R3 are hydrogen atoms or alkyl groups having 1 to 4 carbon atoms and may be the same or different from each other, and ^R1 and ^R4 are linear or branched alkyl groups having 2 to 4 carbon atoms and may be the same or different from each other.)
2. The solid catalyst component for olefin polymerization according to claim 1, wherein the compound is one or more selected from the group consisting of compounds represented by the formula: The solid catalyst component for olefin polymerization according to claim 1, characterized in that the content of the succinic acid diester compound in the total amount of components is 15.0 mass% or more, and the content of titanium atoms is 4.0 to 6.0 mass%. A method for producing a solid catalyst component for olefin polymerization by contacting a dialkoxymagnesium, a titanium halogen compound, and a succinic acid diester compound with each other, comprising the steps of:
contacting the dialkoxymagnesium with the titanium halide compound multiple times;
When the dialkoxymagnesium is first contacted with a titanium halide compound, 2.0 to 5.0 moles of the titanium halide compound are used per 1.0 mole of the dialkoxymagnesium;
the total amount of titanium compounds used is 5.0 to 18.0 moles per 1.0 mole of the dialkoxymagnesium;
Furthermore, the amount of the succinic acid diester compound used is 0.100 to 0.200 mol per 1.0 mol of the dialkoxymagnesium,
adjusting the amounts of the titanium halide compound and the succinic acid diester compound used so that the molar ratio (S/T) represented by the molar amount (S) of the succinic acid diester compound to the molar amount (T) of titanium is 0.50 to 0.72;
A method for producing a solid catalyst component for olefin polymerization, comprising the steps of: a first step of adding titanium tetrachloride to a first mixed suspension obtained by mixing a dialkoxymagnesium with an inert aromatic hydrocarbon solvent in a ratio of the volume of the inert aromatic hydrocarbon solvent to the volume of titanium tetrachloride (inert aromatic hydrocarbon solvent/titanium tetrachloride) of 0.50 to 2.5, and contacting the two with each other to obtain an initial contact product-containing liquid;
a second step of adding a succinic acid diester compound to the initial contact product-containing liquid, contacting them with each other at 80 to 120° C., and then washing with an inert aromatic hydrocarbon solvent to obtain a first contact product;
a third step of mixing the first contact product with an inert aromatic hydrocarbon solvent to obtain a second mixed suspension, then mixing titanium tetrachloride therewith, bringing them into contact with each other, and then washing with an inert aromatic hydrocarbon solvent to obtain a solid catalyst component for olefin polymerization;
5. The method for producing a solid catalyst component for olefin polymerization according to claim 4, wherein the catalyst component comprises at least one of the following: The method for producing a solid catalyst component for olefin polymerization according to claim 4 or 5, characterized in that after the third step, the solid catalyst component for olefin polymerization obtained by carrying out the third step is washed with an inert organic solvent. (I) a solid catalyst component for olefin polymerization according to any one of claims 1 to 3, and (II) a compound represented by the following general formula (2):
R ⁵ _p AlQ _3-p (2)
(In the formula, R ⁵ is an alkyl group having 1 to 6 carbon atoms, Q is a hydrogen atom or a halogen, p is 0<p≦3, and when there are multiple R ^5s , each R ⁵ may be the same or different, and when there are multiple Qs, each Q may be the same or different.)
1. A catalyst for olefin polymerization, comprising an organoaluminum compound represented by the formula: (I) the solid catalyst component for olefin polymerization according to any one of claims 1 to 3, (II) a compound represented by the following general formula (2):
R ⁵ _p AlQ _3-p (2)
(In the formula, R ⁵ is an alkyl group having 1 to 6 carbon atoms, Q is a hydrogen atom or a halogen, p is 0<p≦3, and when there are multiple R ^5s , each R ⁵ may be the same or different, and when there are multiple Qs, each Q may be the same or different.)
and (III) an external electron donor compound. A method for producing an olefin polymer, comprising polymerizing olefins using the olefin polymerization catalyst according to claim 7 or 8. (a) a melt flow rate of 150 to 200 g/10 min;
(b) a flexural modulus of 1700 to 2000 MPa;
(c) In a dynamic viscoelasticity measurement, the ratio (η ratio) of the complex viscosity η* at 190°C and an angular frequency of 0.01 radian/sec to the complex viscosity η* at 190°C and an angular frequency of 100 radian/sec is 4.0 to 6.0;
An olefin polymer characterized by: The olefin polymer according to claim 10, wherein the proportion of the oriented layer in a cross section of an injection-molded plate made of the olefin polymer is 20% or more.

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