JP7195897B2 - Propylene-based resin composition and molded article - Google Patents

Description

TECHNICAL FIELD The present invention relates to a propylene-based resin composition having high rigidity and dimensional stability and a molded article made of the propylene-based resin composition.

Molded products obtained by injection molding propylene-based resin compositions have excellent mechanical properties and moldability, and are relatively advantageous in terms of cost performance compared to other materials. It is being used in many fields.

In recent years, the automotive industry has actively developed eco-friendly and fuel-efficient vehicles, and in the field of automotive materials, there is a demand for materials that are made of resin and thinner for the purpose of weight reduction. For this reason, there are high expectations for improvements in propylene-based materials, which have a proven track record as bumper materials and other automotive materials. The development of materials with excellent dimensional stability (low coefficient of linear expansion) is required while maintaining the same.

On the other hand, polypropylene molded products are generally known to have a large dimensional change (coefficient of linear expansion) with respect to temperature. There were problems such as the creation of gaps and the deterioration of erectability when assembling parts.

Various methods have been disclosed for improving the dimensional stability of such polypropylene moldings. For example, a method for producing a low linear expansion material characterized by the combined use of a low-molecular-weight polyolefin and a propylene-ethylene block copolymer containing a crystalline polypropylene exhibiting a high melt flow rate (MFR) (Patent Document 1); A production method characterized in that the viscosity of the added rubber is within a specific range (Patent Document 2), and a production method characterized in that the mixing ratio and viscosity of the amorphous part and the crystalline part of the propylene-based block copolymer are specified. (Patent Document 3), and a production method characterized by using an inorganic filler such as talc and a carbon fiber having a specific shape in combination (Patent Document 4).

However, in order to be practically used as an automobile material, it is desirable that raw materials are readily available and economically manufactured by a simpler manufacturing method. Further improvements in stability are desired.

JP 2010-077396 A JP-A-5-051498 JP-A-2000-095919 JP-A-2005-232413

In view of the prior art as described above, an object of the present invention is to provide a propylene-based resin composition having high rigidity and low linear expansion, and a molded article formed using the propylene-based resin composition. and

In addition, in order to achieve further thinning, propylene-based materials with high rigidity and low linear expansion are particularly required in the high MFR region with excellent moldability (fluidity), and high stereoregularity in this high MFR region Another object of the present invention is to provide a molded article formed using a resin composition containing a propylene-based polymer.

As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that by using a resin composition containing a specific propylene-based polymer having a high stereoregularity component and an inorganic filler, a propylene-based polymer As a result of the promotion of crystallization, the inventors have found that the rigidity is increased and the linear expansion is decreased, leading to the completion of the present invention.

The propylene-based resin composition of the present invention is
A propylene-based polymer (A1) that satisfies the following requirements (1) to (4), and a propylene-based block copolymer (A2) composed of a propylene homopolymer portion and a propylene/α-olefin copolymer portion. 20 to 99% by mass of at least one component (A) selected from the group,
Ethylene/α-olefin copolymer containing 50 to 95 mol% of structural units derived from ethylene and 5 to 50 mol% of structural units derived from α-olefin having 3 to 20 carbon atoms (B) 0 to 50 mass%,
0 to 20% by mass of a propylene block copolymer (C) different from the propylene block copolymer (A2), and 1 to 70% by mass of an inorganic filler (D)
(where the total of components (A), (B), (C) and (D) is 100% by mass),
The propylene-based polymer propylene-based block copolymer (A2) is
60 to 99% by mass of the propylene-based polymer (A1) as the propylene homopolymer portion, and 55 to 90% by mol of structural units derived from propylene as the propylene/α-olefin copolymer portion and other than propylene 1 to 40% by mass of a propylene/α-olefin copolymer (A3) containing 10 to 45 mol% of a structural unit derived from an α-olefin having 2 to 20 carbon atoms (provided that component (A1) and The total of (A3) is 100% by mass.):
(1) Melt flow rate (MFR) (ASTM D1238, 230° C., under 2.16 kg load) is 0.5 to 1000 g/10 minutes;
(2) When the proportion of components eluted at a temperature of 122°C or higher by the temperature programmed elution fractionation method (TREF) is A% by mass, and the melt flow rate of the requirement (1) is Bg/10 minutes, the following formula satisfy (I);
100≧A≧8.0×EXP(−0.01×B) (I)
(3) the isotactic mesopentat fraction (mmmm) is higher than 98.0% and not higher than 99.9%;
(4) The ratio (Mw/Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) measured by gel permeation chromatography (GPC) is 4.2-20.
The molded article of the present invention is characterized by being formed using the propylene-based resin composition of the present invention.

According to the present invention, a propylene-based resin composition having high rigidity and low linear expansion is obtained.

The present invention will be described in detail below.
The propylene-based resin composition of the present invention (hereinafter also simply referred to as "the composition of the present invention") is
At least one selected from the group consisting of a propylene-based polymer (A1) and a propylene-based block copolymer (A2) composed of a propylene homopolymer portion and a propylene/α-olefin copolymer portion, which will be described later. Component (A) 20 to 99% by mass,
Ethylene/α-olefin copolymer containing 50 to 95 mol% of structural units derived from ethylene and 5 to 50 mol% of structural units derived from α-olefin having 3 to 20 carbon atoms (B) 0 to 50 mass%,
0 to 20% by mass of a propylene block copolymer (C) different from the propylene block copolymer (A2), and 1 to 70% by mass of an inorganic filler (D)
(where the total of components (A), (B), (C) and (D) is 100% by mass). Each component will be described below.

[Component (A)]
The propylene-based polymer (A1) that can be used as the component (A) satisfies the following requirements (1) to (4).
(1) Melt flow rate (MFR) (ASTM D1238, 230° C., under 2.16 kg load) is 0.5 to 1000 g/10 minutes.
(2) When the proportion of components eluted at a temperature of 122°C or higher by the temperature programmed elution fractionation method (TREF) is A% by mass, and the melt flow rate of the requirement (1) is Bg/10 minutes, the following formula (I) is satisfied.
100≧A≧8.0×EXP(−0.01×B) (I)
(3) The isotactic mesopentat fraction (mmmm) is higher than 98.0% and not higher than 99.9%.
(4) The ratio (Mw/Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) measured by gel permeation chromatography (GPC) is 4.2-20.

Further, the propylene-based block copolymer (A2) that can be used as the component (A) is
60 to 99% by mass of the propylene-based polymer (A1) as the propylene homopolymer portion, and 55 to 90% by mol of structural units derived from propylene as the propylene/α-olefin copolymer portion and other than propylene 1 to 40% by mass of a propylene/α-olefin copolymer (A3) containing 10 to 45 mol% of a structural unit derived from an α-olefin having 2 to 20 carbon atoms (provided that component (A1) and The total of (A3) is 100% by mass.).

I. Propylene polymer (A1)
Each requirement of the propylene-based polymer (A1) will be described below.
<Requirement (1)>
The propylene-based polymer (A1) has an MFR (ASTM D1238, 230° C., under 2.16 kg load) of 0.5 to 1000 g/10 min, preferably 1.0 to 800 g/10 min, more preferably 1.0 g/10 min. 5 to 500 g/10 minutes. When the MFR is within the above range, the composition of the present invention has an excellent balance between moldability and mechanical strength. The propylene-based polymer (A1) is preferably 50 to 1000 g/10 min, more preferably 100 to 1000 g/10 min, and particularly preferably 100 to 500 g/10 min. have sex.

<Requirement (2)>
The propylene-based polymer (A1) is defined by the following formula ( I) is satisfied.
100≧A≧8.0×EXP(−0.01×B) (I)
The propylene-based polymer (A1) that satisfies the above formula (I) is preferable in that it has stereoregularity exhibiting certain heat resistance and high rigidity even if the MFR is above a certain level.

<Requirement (3)>
The propylene-based polymer (A1) has an isotactic mesopendate fraction (mmmm) of higher than 98.0% and not higher than 99.9%, preferably 98.1 to 99.9%, more Preferably it is 98.2 to 99.9%. When the isotactic mesopentad fraction is within the above range, the stereoregularity of the propylene-based polymer (A1) tends to be sufficiently high.

Here, the isotactic mesopentad fraction indicates the existence ratio of the pentad isotactic structure in the molecular chain, and five consecutive propylene monomer units are at the center of the chain having a mesostructure. Fraction of propylene structural units. The isotactic mesopentad fraction can be determined by the method described in Examples below.

<Requirement (4)>
The propylene-based polymer (A1) has a weight average molecular weight (Mw) to number average molecular weight (Mn) ratio (Mw/Mn) of 4.2 to 20, preferably 4.5 to 15, as measured by GPC. More preferably 4.8-10. It is preferable from the viewpoint of moldability of the propylene-based polymer that Mw/Mn is within the above range.

The propylene-based polymer (A1) satisfying the above requirements (1) to (4) can be obtained by polymerizing propylene in the presence of an olefin polymerization catalyst described below.
The propylene-based polymer (A1) preferably satisfies the following requirement (5) in addition to the requirements (1) to (4).
(5) The Z-average molecular weight (Mz) of components eluted at a temperature of 122° C. or higher by temperature programmed elution fractionation (TREF) is 300,000 to 5,000,000 as measured by gel permeation chromatography (GPC).

<Requirement (5)>
In the propylene-based polymer (A1), the Z-average molecular weight (Mz) of the component eluted at a temperature of 122° C. or higher by TREF is preferably 300,000 to 5,000,000, more preferably 400,000 to 4,800,000, and particularly preferably 500,000 to 4,500,000. When the Mz of the eluted component is within the above range, it is preferable from the viewpoint of improving the rigidity of the propylene-based resin composition.

<Catalyst for Olefin Polymerization>
The olefin polymerization catalyst that can be used for producing the propylene-based polymer (A1) is not particularly limited, but for example,
(i) a solid titanium catalyst component containing magnesium, titanium, a halogen and an electron donor (internal donor) and satisfying the following requirements (k1) to (k4);
(ii) an organosilicon compound component (external donor) represented by the following formula (II);
(iii) a catalyst [A] containing an organometallic compound component containing an element belonging to Group 1, 2 or 13 of the periodic table, or
A catalyst [B] comprising a prepolymerized catalyst (p) obtained by prepolymerizing propylene with the catalyst [A], the organosilicon compound component (ii), and the organometallic compound component (iii)
is mentioned.
(k1) Titanium content is 2.5% by mass or less.
(k2) The electron donor content is 8 to 30% by mass.
(k3) The electron donor/titanium (mass ratio) is 5 or more.
(k4) Titanium is not substantially desorbed by hexane washing at room temperature.
^R1nSi (OR2) ² ( ^NR3R4 ) ₂ ^- _n ( _II )
In formula (II), R ¹ represents a hydrocarbon group having 1 to 20 carbon atoms, R ² represents a hydrocarbon group having 1 to 4 carbon atoms, R ³ represents a hydrocarbon group having 1 to 12 carbon atoms or hydrogen represents an atom, R ⁴ represents a hydrocarbon group having 1 to 12 carbon atoms, and R ³ and R ⁴ may combine with each other to form a divalent hydrocarbon group having 3 to 20 carbon atoms, n is 0 or 1;

Each component constituting the olefin polymerization catalyst will be described below.
<<Solid titanium catalyst component (i)>>
The solid titanium catalyst component (i) is
(a) solid titanium containing magnesium, titanium, a halogen and an electron donor and from which hexane washing at room temperature does not eliminate titanium;
(b) an aromatic hydrocarbon;
(c) liquid titanium; and (d) an electron donor.

(a) Solid titanium The solid titanium (a) can be obtained by contacting a magnesium compound, a titanium compound, an electron donor (internal donor), and the like by various methods to prepare a known solid titanium catalyst component ( For example, it can be manufactured according to Japanese Unexamined Patent Publication No. 4-096911, Japanese Unexamined Patent Publication No. 58-83006, Japanese Unexamined Patent Publication No. 8-143580, etc.).

Preferably, the magnesium compound is used in a solid state. The solid-state magnesium compound may be the magnesium compound itself in a solid state, or an adduct with an electron donor. Examples of the magnesium compound include magnesium compounds described in JP-A-2004-2742, specifically magnesium chloride, ethoxymagnesium chloride, butoxymagnesium and the like. Examples of the electron donor include compounds capable of solubilizing magnesium compounds described in JP-A-2004-2742, specifically alcohols, aldehydes, amines, carboxylic acids and mixtures thereof. The amount of the magnesium compound and the electron donor to be used varies depending on their types, contact conditions, etc., but the amount of the magnesium compound to the liquid electron donor is 0.1 to 20 mol/liter, preferably 0.5 to 0.5 mol/liter. It can be used in an amount of 5 mol/liter.

Preferably, the titanium compound is used in a liquid state. Examples of such titanium compounds include tetravalent titanium compounds represented by the following formula (III).
Ti(OR ⁵ ) _g X _4-g (III)
^In formula (III), R5 is a hydrocarbon group, X is a halogen atom, and 0≤g≤4.

Titanium tetrachloride is particularly preferable as the titanium compound. Moreover, you may use the said titanium compound in combination of 2 or more types.
Examples of the electron donor (internal donor) include compounds represented by the following formula (IV) (hereinafter also referred to as "compound (IV)").

式（IV）中、Ｒは、炭素原子数１～１０、好ましくは２～８、より好ましくは３～６の直鎖状もしくは分岐状のアルキル基を示し、Ｒ'は炭素数１～１０の直鎖状もしくは分岐状のアルキル基を示し、ｎは０～４の整数を示す。本発明では、ｎが０の化合物が好ましい。

In formula (IV), R represents a linear or branched alkyl group having 1 to 10 carbon atoms, preferably 2 to 8 carbon atoms, more preferably 3 to 6 carbon atoms; It represents a linear or branched alkyl group, and n represents an integer of 0-4. In the present invention, compounds in which n is 0 are preferred.

Examples of alkyl groups for R and R' are methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, tert-butyl, pentyl, hexyl, heptyl. group, octyl group, nonyl group, decyl group, and the like.

Specific examples of the compound (IV) include dimethyl phthalate, methyl ethyl phthalate, diethyl phthalate, n-propyl phthalate, diisopropyl phthalate, di-n-butyl phthalate, diisobutyl phthalate, and di-n-phthalate. Pentyl, dineopentyl phthalate, di-n-hexyl phthalate, di-n-heptyl phthalate, di(methylhexyl) phthalate, di(dimethylpentyl) phthalate, di(ethylpentyl) phthalate, di(2, 2,3-trimethylbutyl), di-n-octyl phthalate, and di-2-ethylhexyl phthalate. Among these, diisobutyl phthalate is particularly preferred.

In the present invention, an electron donor other than the compound (IV) may be used as the electron donor (internal donor). Other electron donors include, for example, compounds having two or more ether bonds existing via a plurality of atoms (hereinafter also referred to as "polyether compounds").

Examples of the polyether compound include compounds in which the atoms present between ether bonds are carbon, silicon, oxygen, nitrogen, sulfur, phosphorus, boron, or two or more atoms selected from these. . Among these, preferred are compounds in which relatively bulky substituents are bonded to atoms between ether bonds and atoms present between two or more ether bonds contain a plurality of carbon atoms. For example, a polyether compound represented by the following formula (3) is preferred.

前記式（３）において、ｍは１～１０の整数、好ましくは３～１０の整数、より好ましくは３～５の整数である。Ｒ¹¹、Ｒ¹²、Ｒ³¹～Ｒ³⁶は、それぞれ独立に、水素原子、または炭素、水素、酸素、フッ素、塩素、臭素、ヨウ素、窒素、硫黄、リン、ホウ素およびケイ素から選択される少なくとも１種の元素を有する置換基である。Ｒ¹¹およびＲ¹²は、それぞれ独立に、好ましくは炭素原子数１～１０の炭化水素基であり、より好ましくは炭素原子数２～６の炭化水素基である。Ｒ³¹～Ｒ³⁶は、それぞれ独立に、好ましくは水素原子または炭素原子数１～６の炭化水素基である。

In the above formula (3), m is an integer of 1-10, preferably an integer of 3-10, more preferably an integer of 3-5. R ¹¹ , R ¹² , R ³¹ to R ³⁶ are each independently a hydrogen atom or at least one selected from carbon, hydrogen, oxygen, fluorine, chlorine, bromine, iodine, nitrogen, sulfur, phosphorus, boron and silicon. It is a substituent having a seed element. R ¹¹ and R ¹² are each independently preferably a hydrocarbon group having 1 to 10 carbon atoms, more preferably a hydrocarbon group having 2 to 6 carbon atoms. R ³¹ to R ³⁶ are each independently preferably a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms.

Specific examples of R ¹¹ and R ¹² include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, isopentyl, neopentyl, hexyl, heptyl, octyl, 2 -ethylhexyl group, decyl group, cyclopentyl group and cyclohexyl group. Among these, ethyl group, n-propyl group, isopropyl group, n-butyl group and isobutyl group are preferred. Specific examples of R ³¹ to R ³⁶ include hydrogen atom, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group and isobutyl group. Among these, a hydrogen atom and a methyl group are preferred. Optional R ¹¹ , R ¹² , R ³¹ to R ³⁶ (preferably R ¹¹ and R ¹² ) may jointly form a ring other than a benzene ring, and the main chain contains an atom other than carbon. It may be

Specific examples of the polyether compound include 2,2-dicyclohexyl-1,3-dimethoxypropane, 2,2-diethyl-1,3-dimethoxypropane, 2,2-dipropyl-1,3-dimethoxypropane, 2 , 2-dibutyl-1,3-dimethoxypropane, 2-methyl-2-propyl-1,3-dimethoxypropane, 2-methyl-2-ethyl-1,3-dimethoxypropane, 2-methyl-2-isopropyl- 1,3-dimethoxypropane, 2-methyl-2-cyclohexyl-1,3-dimethoxypropane, 2,2-bis(2-cyclohexylethyl)-1,3-dimethoxypropane, 2-methyl-2-isobutyl-1 , 3-dimethoxypropane, 2-methyl-2-(2-ethylhexyl)-1,3-dimethoxypropane, 2,2-diisobutyl-1,3-dimethoxypropane, 2,2-bis(cyclohexylmethyl)-1, 3-dimethoxypropane, 2,2-diisobutyl-1,3-diethoxypropane, 2,2-diisobutyl-1,3-dibutoxypropane, 2-isobutyl-2-isopropyl-1,3-dimethoxypropane, 2, 2-di-s-butyl-1,3-dimethoxypropane, 2,2-di-t-butyl-1,3-dimethoxypropane, 2,2-dineopentyl-1,3-dimethoxypropane, 2-isopropyl-2 -isopentyl-1,3-dimethoxypropane, 2-cyclohexyl-2-cyclohexylmethyl-1,3-dimethoxypropane, 2,3-dicyclohexyl-1,4-diethoxybutane, 2,3-diisopropyl-1,4- Diethoxybutane, 2,4-diisopropyl-1,5-dimethoxypentane, 2,4-diisobutyl-1,5-dimethoxypentane, 2,4-diisoamyl-1,5-dimethoxypentane, 3-methoxymethyltetrahydrofuran, 3 -methoxymethyldioxane, 1,2-diisobutoxypropane, 1,2-diisobutoxyethane, 1,3-diisoamyloxyethane, 1,3-diisoamyloxypropane, 1,3-diisoneopentyloxy Ethane, 1,3-dineopentyloxypropane, 2,2-tetramethylene-1,3-dimethoxypropane, 2,2-pentamethylene-1,3-dimethoxypropane, 2,2-hexamethylene-1,3 -dimethoxypropane, 1,2-bis(methoxymethyl)cyclohexane, 2-cyclohexyl-2-ethoxymethyl-1,3-di Ethoxypropane, 2-cyclohexyl-2-methoxymethyl-1,3-dimethoxypropane, 2,2-diisobutyl-1,3-dimethoxycyclohexane, 2-isopropyl-2-isoamyl-1,3-dimethoxycyclohexane, 2-cyclohexyl -2-methoxymethyl-1,3-dimethoxycyclohexane, 2-isopropyl-2-methoxymethyl-1,3-dimethoxycyclohexane, 2-isobutyl-2-methoxymethyl-1,3-dimethoxycyclohexane, 2-cyclohexyl-2 -ethoxymethyl-1,3-diethoxycyclohexane, 2-cyclohexyl-2-ethoxymethyl-1,3-dimethoxycyclohexane, 2-isopropyl-2-ethoxymethyl-1,3-diethoxycyclohexane, 2-isopropyl-2 -ethoxymethyl-1,3-dimethoxycyclohexane, 2-isobutyl-2-ethoxymethyl-1,3-diethoxycyclohexane, 2-isobutyl-2-ethoxymethyl-1,3-dimethoxycyclohexane and the like can be exemplified. .

Among these, 1,3-diethers are preferred, and 2-isopropyl-2-isobutyl-1,3-dimethoxypropane, 2,2-diisobutyl-1,3-dimethoxypropane, 2-isopropyl-2-isopentyl- More preferred are 1,3-dimethoxypropane, 2,2-dicyclohexyl-1,3-dimethoxypropane and 2,2-bis(cyclohexylmethyl)1,3-dimethoxypropane. One of these compounds may be used, or two or more thereof may be used in combination.

The solid titanium (a) can be prepared by contacting the magnesium compound, the titanium compound, and the electron donor. At this time, it is preferable to use a magnesium compound in a solid state suspended in a hydrocarbon solvent. Further, when these components are brought into contact, the liquid form of the titanium compound may be used once to produce the solid (1), and the obtained solid (1) is further brought into contact with the liquid form of the titanium compound. to form a solid (2). Further, it is preferable to prepare the solid titanium (a) after washing the solid (1) or (2) with a hydrocarbon solvent as necessary.

The contact of each component as described above is usually carried out at a temperature of -70°C to +200°C, preferably -50°C to +150°C, more preferably -30°C to +130°C. The amount of each component used in preparing the solid titanium (a) varies depending on the preparation method and cannot be generally defined. In an amount of 0.1 to 5 mol, the titanium compound can be used in an amount of 0.01 to 1000 mol, preferably 0.1 to 200 mol.

In the present invention, the solid material (1) or (2) thus obtained can be used as it is as solid titanium (i), but this solid material is washed with a hydrocarbon solvent at 0 to 150°C. is preferred.

Examples of the hydrocarbon solvent include aliphatic hydrocarbon solvents such as hexane, heptane, octane, nonane, decane, and cetane; non-halogen aromatic hydrocarbon solvents such as toluene, xylene, and benzene; A hydrocarbon solvent or the like is used. Among these, aliphatic hydrocarbon solvents and halogen-free aromatic hydrocarbon solvents are preferably used.

When washing the solids, the hydrocarbon solvent is used in an amount of usually 10-500 ml, preferably 20-100 ml, per 1 g of the solids. The solid titanium (a) thus obtained contains magnesium, titanium, halogen and an electron donor. The solid titanium (a) preferably has an electron donor/titanium (mass ratio) of 6 or less.
The solid titanium (a) obtained in this manner does not desorb titanium by washing with hexane at room temperature.

(b) Aromatic hydrocarbon Examples of the aromatic hydrocarbon (b) used in contact with the solid titanium (a) include benzene, toluene, xylene, ethylbenzene, and halogen-containing hydrocarbons thereof. . Among these, xylene (especially para-xylene) is preferred. By bringing the solid titanium (a) into contact with such an aromatic hydrocarbon (b), so-called "surplus titanium compounds" that produce low stereoregularity components by-products can be reduced.

(c) Liquid Titanium As the liquid titanium (c) used for contact with the solid titanium (a), the same titanium compounds as those used in preparing the solid titanium (a) can be mentioned. can. Among them, titanium tetrahalides are preferred, and titanium tetrachloride is particularly preferred.

(d) Electron donor Examples of the electron donor (d) used in contact with the solid titanium (a) are the same as those exemplified for the electron donor (internal donor) described above. can. Among them, it is preferable to use the same electron donor as used in the preparation of the solid titanium (a).

Preparation method of solid titanium catalyst component (i) Solid titanium (a), aromatic hydrocarbon (b), liquid titanium (c) and electron donor (d) are usually contacted at 110 to 160°C, preferably It is carried out at a temperature of 115° C. to 150° C. for 1 minute to 10 hours, preferably 10 minutes to 5 hours.

In this contact, the aromatic hydrocarbon (b) is generally used in an amount of 1-10000 ml, preferably 5-5000 ml, more preferably 10-1000 ml, per 1 g of solid titanium (a). Liquid titanium (c) is usually used in an amount of 0.1 to 50 ml, preferably 0.2 to 20 ml, particularly preferably 0.3 to 10 ml, per 100 ml of aromatic hydrocarbon (b). The electron donor (d) is generally used in an amount of 0.01-10 ml, preferably 0.02-5 ml, particularly preferably 0.03-3 ml, per 100 ml of the aromatic hydrocarbon (b).

The contact order of solid titanium (a), aromatic hydrocarbon (b), liquid titanium (c) and electron donor (d) is not particularly limited, and they can be contacted simultaneously or sequentially.
Solid titanium (a), aromatic hydrocarbon (b), liquid titanium (c) and electron donor (d) are preferably brought into contact with stirring under an inert gas atmosphere. For example, in a sufficiently nitrogen-substituted glass flask equipped with a stirrer, a slurry of solid titanium (a), aromatic hydrocarbon (b), liquid titanium (c) and electron donor (d) is added at the above temperature. , the stirrer is stirred at a rotation speed of 100 to 1000 rpm, preferably 200 to 800 rpm, for the above time to obtain the solid titanium (a), the aromatic hydrocarbon (b), the liquid titanium (c) and the electron donor ( d) is preferably brought into contact.

After contact, the solid titanium (a) and the aromatic hydrocarbon (b) can be separated by filtration.
By contacting the solid titanium (a) with the aromatic hydrocarbon (b), a solid titanium catalyst component (i) having a lower titanium content than the solid titanium (a) is obtained. Specifically, a solid titanium catalyst component (i) having a titanium content of 25% by mass or more, preferably 30 to 95% by mass, and more preferably 40 to 90% by mass less than that of solid titanium (a) is obtained.

The solid titanium catalyst component (i) obtained as described above contains magnesium, titanium, a halogen and an electron donor, and satisfies the following requirements (k1) to (k4), preferably the following requirement (k5): further satisfies

(k1) The titanium content of the solid titanium catalyst component (i) is 2.5% by mass or less, preferably 2.2 to 0.1% by mass, more preferably 2.0 to 0.2% by mass, particularly preferably is 1.8-0.3% by weight, most preferably 1.6-0.4% by weight.
(k2) The content of the electron donor is 8 to 30% by mass, preferably 9 to 25% by mass, more preferably 10 to 20% by mass.
(k3) electron donor/titanium (mass ratio) is 5 or more, preferably 5.2 to 35, more preferably 5.5 to 30, particularly preferably 6.0 to 25.
(k4) The solid titanium catalyst component (i) does not substantially desorb titanium by washing with hexane at room temperature. The washing of the solid titanium catalyst component (i) with hexane means that 1 g of the solid titanium catalyst component (i) is usually washed with 10 to 500 ml, preferably 20 to 100 ml of hexane for 5 minutes. say. Room temperature is 15-25°C. Further, "substantially no desorption of titanium" means that the concentration of titanium in the hexane washing liquid is 0.1 g/liter or less.
(k5) The solid titanium catalyst component (i) has an average particle size of 5 to 80 μm, preferably 7 to 75 μm, more preferably 8 to 70 μm, particularly preferably 10 to 65 μm.

Here, the amounts of magnesium, halogen, titanium, and electron donor are respectively mass % per unit mass of the solid titanium catalyst component (i), and magnesium, halogen, and titanium are determined by plasma emission spectrometry (ICP method). , the electron donor is quantified by gas chromatography. Also, the average particle size of the catalyst is measured by a centrifugal sedimentation method using decalin solvent.

When the solid titanium catalyst component (i) as described above is used as a catalyst component for olefin polymerization, it is possible to polymerize propylene with high activity, and the amount of polypropylene with low stereoregularity produced is small. Polypropylene can be produced stably.

<<Organosilicon compound component (ii)>>
The organosilicon compound component (ii) (external donor) constituting the olefin polymerization catalyst is represented by the following formula (II).
^R1nSi (OR2) ² ( ^NR3R4 ) ₂ ^- _n ( _II )
In formula (II), R ¹ represents a hydrocarbon group having 1 to 20 carbon atoms, R ² represents a hydrocarbon group having 1 to 4 carbon atoms, R ³ represents a hydrocarbon group having 1 to 12 carbon atoms or hydrogen represents an atom, R ⁴ represents a hydrocarbon group having 1 to 12 carbon atoms, and R ³ and R ⁴ may combine with each other to form a divalent hydrocarbon group having 3 to 20 carbon atoms, n is 0 or 1;

Examples of R ¹ include an alicyclic hydrocarbon group having 3 to 20 carbon atoms, a branched or linear alkyl group having 1 to 20 carbon atoms, and an aralkyl group having 7 to 20 carbon atoms.
Examples of the alicyclic hydrocarbon group having 3 to 20 carbon atoms include a cyclobutyl group, a cyclopentyl group, a cyclopentenyl group, a cyclopentadienyl group, a cyclohexyl group, a cyclohexynyl group, and these groups having a substituent. mentioned. Moreover, the alicyclic hydrocarbon group may be a polycyclic group such as an adamantyl group or a methyladamantyl group.

Regarding the branched or linear alkyl group having 1 to 20 carbon atoms and the aralkyl group having 7 to 20 carbon atoms, the carbon adjacent to Si may be a primary carbon or a secondary carbon. or a tertiary carbon.

Hydrocarbon groups in which the carbon adjacent to Si is a primary carbon include methyl group, ethyl group, propyl group, n-butyl group, n-amyl group, i-butyl group, i-amyl group, and the like. to 20 primary alkyl groups, and benzyl groups, and the like.

Examples of the hydrocarbon group in which the carbon adjacent to Si is a secondary carbon include a secondary alkyl group having 1 to 20 carbon atoms such as an iso-propyl group, a sec-butyl group and a sec-amyl group, and α-methyl A benzyl group and the like can be mentioned.

Hydrocarbon groups in which the carbon adjacent to Si is a tertiary carbon include tertiary alkyl groups having 1 to 20 carbon atoms such as tert-butyl and tert-amyl, and α,α-dimethylbenzyl ( cumyl group) and the like.

Among these, ethyl group, iso-propyl group, cyclopentyl group and cyclobutyl group are preferred, and ethyl group and cyclopentyl group are particularly preferred.
Examples of R ² include methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group, iso-butyl group, tert-butyl group, sec-butyl group, n-pentyl group, iso- pentyl group, cyclopentyl group, n-hexyl group, cyclohexyl group and the like. Among these, a methyl group and an ethyl group are particularly preferred.

Examples of R ³ include hydrogen, methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group, iso-butyl group, tert-butyl group, sec-butyl group, n-pentyl group, iso-pentyl group, cyclopentyl group, n-hexyl group, cyclohexyl group, octyl group and the like. Among these, an ethyl group is particularly preferred.

Examples of R ⁴ include methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group, iso-butyl group, tert-butyl group, sec-butyl group, n-pentyl group, iso- pentyl group, cyclopentyl group, n-hexyl group, cyclohexyl group, octyl group and the like. Among these, an ethyl group is particularly preferred.

Examples of the divalent hydrocarbon group having 3 to 20 carbon atoms formed by bonding R ³ and R ⁴ together include butane-1,4-diyl group and pentane-1,5-diyl group. , propane-1,3-diyl group, hexane-1,6-diyl group, octane-1,8-diyl group, and the like. These correspond to cases where the groups represented by NR ³ R ⁴ are respectively a pyrrolidino group, a piperidino group, an azetidino group, an azepano group and an azonano group. Said divalent hydrocarbon group is preferably a butane-1,4-diyl group.

Specific examples of compounds in which n is 1 among the organosilicon compounds represented by formula (II) include cyclobutyl(diethylamino)dimethoxysilane, cyclopentyl(diethylamino)dimethoxysilane, cyclopentenyl(diethylamino)dimethoxysilane, cyclopenta dienyl(diethylamino)dimethoxysilane, cyclohexyl(diethylamino)dimethoxysilane, ethyl(diethylamino)dimethoxysilane, n-propyl(diethylamino)dimethoxysilane, isopropyl(diethylamino)dimethoxysilane, isobutyl(diethylamino)dimethoxysilane, n-butyl(diethylamino) ) dimethoxysilane, tert-butyl(diethylamino)dimethoxysilane, ethyl(piperidinodiethylamino)dimethoxysilane, isopropyl(diethylamino)dimethoxysilane, tert-butyl(diethylamino)dimethoxysilane, isopropylpyrrolidinodimethoxysilane, isopropylpiperidinodimethoxysilane silane and the like.

Among the organosilicon compounds represented by the formula (II), specific examples of compounds in which n is 0 include dipyrrolidinodimethoxysilane, dipiperidinodimethoxysilane, bis(dimethylamino)dimethoxysilane, bis(diethylamino ) dimethoxysilane, diethylamino(methylethylamino)dimethoxysilane, piperidino(diethylamino)dimethoxysilane, piperidino(dimethylamino)dimethoxysilane, and the like.

Among the organosilicon compounds represented by the formula (II), ethyl(diethylamino)dimethoxysilane and cyclopentyldiethylaminodimethoxysilane are preferred from the viewpoint of high stereoregularity, particularly from the viewpoint of increasing the TREF high-temperature elution ratio.

The organosilicon compound component (ii) described above may be used alone or in combination of two or more.
By using the solid titanium catalyst component (i) and the organosilicon compound component (ii) in combination, a propylene-based polymer having high stereoregularity can be obtained.

<<organometallic compound component (iii)>>
The organometallic compound component (iii) constituting the olefin polymerization catalyst of the present invention is an organometallic compound containing a metal belonging to Group 1, Group 2 or Group 13 of the periodic table. complex alkyl compounds of group metals and aluminum, organic metal compounds of group 2 metals, and the like. Two or more kinds of the organometallic compound component (iii) may be used in combination.

The organoaluminum compound is represented, for example, by the following formula.
R ^a _n AlX _3-n
In the formula, R ^a is a hydrocarbon group having 1-12 carbon atoms, X is halogen or hydrogen, and n is 1-3.

R ^a is a hydrocarbon group having 1 to 12 carbon atoms, such as an alkyl group, a cycloalkyl group or an aryl group, specifically methyl, ethyl, n-propyl, isopropyl, isobutyl, pentyl, hexyl, Octyl, cyclopentyl, cyclohexyl, phenyl, tolyl and the like.

Moreover, the compound shown by the following formula can also be mentioned as said organoaluminum compound.
R ^a _n AlY _3-n
In the formula, R ^a is the same as above, Y is —OR ^b group, —OSiR ^c ₃ group, —OAlR ^d ₂ group, —NR ^e ₂ group, —SiR ^f ₃ group or —N(R ^g )AlR ^h ₂ groups, n is 1 to 2, R ^b , R ^c , R ^d and R ^h are methyl group, ethyl group, isopropyl group, isobutyl group, cyclohexyl group, phenyl group, etc., and R ^e is Hydrogen, methyl group, ethyl group, isopropyl group, phenyl group, trimethylsilyl group and the like, and R ^f and R ^g are methyl group, ethyl group and the like.

Specific examples of such organoaluminum compounds include the following compounds.
A compound represented by R ^a _n Al(OR ^b ) _3-n , such as dimethylaluminum methoxide, diethylaluminum ethoxide, diisobutylaluminum methoxide, and the like.
Compounds represented by R ^a _n Al(OSiR ^c ) _3-n , such as Et ₂ Al(OSiMe ₃ ), (iso-Bu) ₂ Al(OSiMe ₃ ), (iso-Bu) ₂ Al(OSiEt ₃ ) Such.
^RanAl ( _OAlRd2 ) _{3 -} ^nEt2AlOAlEt2 , (iso _{-Bu)2AlOAl(iso-Bu)2 and the like} .
Among the above organoaluminum compounds, an organoaluminum compound represented by R ^a ₃ Al is preferably used.

<<Method for producing olefin polymerization catalyst>>
The olefin polymerization catalyst can be produced by a method comprising the step of contacting the solid titanium catalyst component (i), the organosilicon compound component (ii), and the organometallic compound component (iii). .

In the present invention, when forming the olefin polymerization catalyst from each of these components (i), (ii) and (iii), other components can be used as necessary.
In the present invention, the prepolymerization catalyst (p) may be formed from each component as described above. The prepolymerization catalyst (p) is formed by prepolymerizing propylene in the presence of the components (i), (ii) and (iii) described above and other optional components. Such a prepolymerization catalyst (p) usually forms an olefin polymerization catalyst together with the organosilicon compound (ii) and the organometallic compound (iii), but only the prepolymerization catalyst (p) is used as an olefin polymerization catalyst. sometimes it is possible.

<Method for Producing Propylene Polymer (A1)>
In the method for producing the propylene-based polymer (A1), propylene is polymerized in the presence of the olefin polymerization catalyst described above.
When propylene is polymerized, a random copolymer can be produced by allowing a small amount of olefin other than propylene or a small amount of diene compound to coexist in the polymerization system in addition to propylene. Such olefins other than propylene include ethylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-octene, 3-methyl- Examples include olefins having 2 to 8 carbon atoms such as 1-butene. Among these, ethylene is preferred. In the case of random copolymers, the content of comonomers other than propylene is preferably 6 mol % or less, more preferably 3 mol % or less.

In the present invention, polymerization can be carried out by either a liquid phase polymerization method such as solution polymerization or suspension polymerization, or a gas phase polymerization method. When the polymerization takes the reaction form of slurry polymerization, an inert organic solvent can be used as the reaction solvent, and an olefin that is liquid at the reaction temperature can also be used.

Specific examples of inert organic solvents include aliphatic hydrocarbons such as propane, butane, pentane, hexane, heptane, octane, decane, dodecane, and kerosene; alicyclic hydrocarbons; aromatic hydrocarbons; Hydrogen, or a contact product thereof can be mentioned. Among these, it is particularly preferable to use aliphatic hydrocarbons.

In the polymerization, the solid titanium catalyst component (i) or the prepolymerization catalyst (p) is usually used in an amount of about 1×10 ⁻⁵ to 1 millimole, preferably about 1×1 millimole in terms of titanium atoms per liter of polymerization volume. It is used in amounts of 10 ^-4 to 0.1 mmol.

The organosilicon compound (ii) is generally used in an amount of about 0.001 mol to 10 mol, preferably 0.01 mol to 5 mol, per 1 mol of the metal atom in the organometallic compound (iii).
The organometallic compound (iii) is used in an amount such that the metal atom in the compound (iii) is usually about 1 to 2000 mol, preferably about 2 to 500 mol, per 1 mol of the titanium atom in the polymerization system. be done.

If the prepolymerization catalyst (p) is used during this polymerization, the organosilicon compound (ii) and/or the organometallic compound (iii) may not need to be added. When the olefin polymerization catalyst is formed from the prepolymerized catalyst (p), component (ii) and component (iii), each of these components (ii) and (iii) can be used in amounts as described above.

If hydrogen is used during polymerization, the molecular weight of the propylene polymer to be obtained can be adjusted, and a polymer with a large MFR can be obtained.
In the present invention, the polymerization is usually carried out at a temperature of about 20-150° C., preferably about 50-100° C., and under a pressure of normal pressure to 100 kg/cm ² , preferably about 2-50 kg/cm ² . .

In the present invention, polymerization can be carried out in any of batch, semi-continuous and continuous methods. Furthermore, the polymerization can be carried out in two or more stages by changing the reaction conditions. Further, in the present invention, a homopolymer of propylene may be produced, or a random copolymer or block copolymer may be produced from an olefin other than propylene.

II. Propylene-based block copolymer (A2)
The propylene-based block copolymer (A2) contains 60 to 99% by mass, preferably 70 to 97% by mass, more preferably 75 to 95% by mass of the propylene-based polymer (A1) as the propylene homopolymer portion. 1 to 40% by mass, preferably 3 to 30% by mass, more preferably 5 to 25% by mass of the propylene/α-olefin copolymer (A3) (with the exception that component (A1) and (A3) is 100% by mass).

The propylene-based block copolymer (A2) can be produced by mixing (for example, melt-kneading) the propylene-based polymer (A1) and the propylene/α-olefin copolymer (A3). A propylene homopolymer is used as the propylene-based polymer (A1) constituting the propylene-based block copolymer (A2).

By forming the propylene-based block copolymer (A2) using the propylene-based polymer (A1) and the propylene/α-olefin copolymer (A3) in this way, rigidity, heat resistance, and impact resistance can be improved. It is possible to form a molded body excellent in balance with.

III. Propylene/α-olefin copolymer (A3)
The propylene/α-olefin copolymer (A3) is a copolymer of propylene and an α-olefin having 2 to 20 carbon atoms other than propylene, and contains 40 to 90 mol% of structural units derived from propylene. It preferably contains within the range of 45 to 85 mol%, and contains 10 to 60 mol%, preferably within the range of 15 to 55 mol% of structural units derived from the α-olefin (provided that the structural unit derived from propylene The sum of structural units and structural units derived from α-olefin is 100 mol%.).

Examples of α-olefins having 2 to 20 carbon atoms other than propylene include ethylene, 1-butene, 1-pentene, 3-methyl-1-butene, 1-hexene, 4-methyl-1-pentene, 3-methyl-1 -pentene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene and the like. These may be used alone or in combination of two or more. Among these, ethylene is preferred.

The MFR (ASTM D1238E, measurement temperature 230°C, load 2.16 kg) of the propylene/α-olefin copolymer (A3) is preferably 0.005 g/10 min or more, more preferably 0.1 g/10 min or more. , more preferably 0.3 to 20 g/10 minutes.

The propylene/α-olefin copolymer (A3) is produced by various known production methods, for example, by copolymerizing propylene and an α-olefin having 2 to 20 carbon atoms other than propylene in the presence of a metallocene catalyst. can do.
The propylene/α-olefin copolymer (A3) may be used alone or in combination of two or more.

[Ethylene/α-olefin copolymer (B)]
The composition of the present invention may optionally contain an ethylene/α-olefin copolymer (B).
The ethylene/α-olefin copolymer (B) is a random copolymer of ethylene and an α-olefin having 3 to 20 carbon atoms, and contains 50 to 95 mol%, preferably 55 It contains 5 to 50 mol%, preferably 10 to 45 mol% of structural units derived from the α-olefin. By adding the ethylene/α-olefin copolymer (B) to the component (A), the impact resistance can be further improved.

α-olefins having 3 to 20 carbon atoms include propylene, 1-butene, 1-pentene, 3-methyl-1-butene, 1-hexene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene and the like. These may be used alone or in combination of two or more. Among these, propylene, 1-butene, 1-hexene and 1-octene are preferred, and 1-butene and 1-octene are more preferred.

MFR (ASTM D1238E, measurement temperature 230°C, load 2.16 kg) of the ethylene/α-olefin copolymer (B) is preferably 0.1 to 50 g/10 min, more preferably 0.3 to 20 g/10 min. 10 minutes, more preferably 0.5 to 10 g/10 minutes. The density of the ethylene/α-olefin copolymer (B) is preferably 0.850 to 0.920 kg/m ³ , more preferably 0.855 to 0.900 kg/m ³ .

As the ethylene/α-olefin copolymer (B), one produced by a known method may be used, or a commercially available product may be used. Preferred commercially available products include, for example, "Tafmer (registered trademark) A" series and "Tafmer (registered trademark) H" series manufactured by Mitsui Chemicals, Inc., and "Engage (registered trademark)" series manufactured by DuPont Dow. , "Exact (registered trademark)" series manufactured by ExxonMobil, and the like.
The ethylene/α-olefin copolymer (B) may be used alone or in combination of two or more.

[Propylene block copolymer (C)]
The composition of the present invention may optionally contain a propylene-based block copolymer (C) different from the propylene-based block copolymer (A2).
The propylene-based block copolymer (C) has a melt flow rate (MFR) of 1 to 200 g/10 min, preferably 2 ~150 g/10 min, more preferably 5-100 g/10 min.

The propylene-based block copolymer (C), when fractionated with an n-decane solvent, contains a component soluble in n-decane at 23°C (hereinafter also referred to as a “decane-soluble portion”) and n-decane at 23°C. Insoluble component (hereinafter also referred to as "decane-insoluble part"). The ratio of these components is preferably 5 to 50% by mass, more preferably 10 to 30% by mass, of the decane-soluble portion, and 50 to 95% by mass, more preferably 70 to 90% by mass of the decane-insoluble portion. is. When the content of the decane-soluble portion and the decane-insoluble portion is within the above range, a molded article having excellent mechanical properties such as rigidity and impact resistance can be obtained.

The decane-insoluble part usually consists only of structural units derived from propylene, but a structure derived from a small amount, for example, 10 mol% or less, preferably 5 mol% or less, of another monomer (such as an α-olefin other than propylene). May contain units.

The decane-soluble portion is mainly composed of the propylene/α-olefin copolymer, but may contain a part of the propylene homopolymer, such as by-products generated during polymerization such as low-molecular-weight products.

The α-olefin of the propylene/α-olefin copolymer in the decane-soluble portion is ethylene and/or an α-olefin having 4 to 12 carbon atoms. Specific examples of such α-olefins include ethylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-heptene, 1-octene, 1-nonene, 1-decene and 1-dodecene. Among these, ethylene is preferred.

The intrinsic viscosity ([η]) of the decane-soluble portion of the propylene-based block copolymer (C) measured in decalin at 135°C is preferably 1.0 to 10.0 dl/g, more preferably 2.0. ~9.0 dl/g.

The propylene-based block copolymer (C) can be produced by referring to a conventionally known method, for example, the method described in [0018]-[0026] of JP-A-2004-323545.
The propylene-based block copolymer (C) may be used alone or in combination of two or more.

[Inorganic filler (D)]
Examples of the inorganic filler (D) contained in the composition of the present invention include talc, clay, mica, calcium carbonate, magnesium hydroxide, ammonium phosphate, silicates, carbonates, carbon black, and magnesium sulfate fiber. , glass fiber, carbon fiber, and the like. These may be used alone or in combination of two or more. Talc is preferably used as the inorganic filler (D) in the composition of the present invention.

[Other ingredients]
The composition of the present invention includes resins, rubbers, fillers, weather stabilizers, heat stabilizers, antistatic agents, slip Other ingredients such as inhibitors, anti-blocking agents, anti-fogging agents, lubricants, pigments, dyes, plasticizers, anti-aging agents, hydrochloric acid absorbers, antioxidants, nucleating agents, etc. can be incorporated. The blending amount of the other components in the propylene-based resin composition of the present invention is not particularly limited as long as it does not impair the object of the present invention.

[Aspect of propylene-based resin composition]
The propylene-based resin composition of the present invention is a resin composition containing the above-described component (A) and inorganic filler (D) as essential components. It can be appropriately blended according to.

As a preferred embodiment of the propylene-based resin composition of the present invention,
20 to 90% by mass of the propylene-based block copolymer (A2), 1 to 50% by mass of the ethylene/α-olefin copolymer (B), and 1 to 70% by mass of the inorganic filler (D) ( provided that the total of components (A2), (B) and (D) is 100% by mass.) Propylene-based resin composition (hereinafter also referred to as "first composition");
20 to 80% by mass of the propylene-based polymer (A1), 1 to 50% by mass of the ethylene/α-olefin copolymer (B), 1 to 20% by mass of the propylene-based block copolymer (C), and the A propylene-based resin composition (hereinafter " Also referred to as "second composition");
40 to 99% by mass of the propylene-based polymer (A1) and 1 to 60% by mass of the inorganic filler (D) (provided that the total of components (A1) and (D) is 100% by mass). Propylene-based resin composition (hereinafter also referred to as "third composition")
etc.

<First composition>
A first composition of the present invention is a resin composition containing the propylene block copolymer (A2), the ethylene/α-olefin copolymer (B) and the inorganic filler (D).

In the first composition of the present invention, a propylene homopolymer is used as the propylene-based polymer (A1) constituting the propylene-based block copolymer (A2).
The first composition of the present invention is prepared by mixing the propylene-based polymer (A1) and the propylene/α-olefin copolymer (A3) to form a propylene-based block copolymer (A2), It can be prepared by mixing the ethylene/α-olefin copolymer (B) and the inorganic filler (D).

The contents of components (A2), (B) and (D) in the first composition of the present invention are such that when the total of components (A2), (B) and (D) is 100% by mass, component (A2) is 20 to 90% by mass, preferably 25 to 85% by mass, more preferably 30 to 80% by mass; component (B) is 1 to 50% by mass, preferably 5 to 40% by mass; It is more preferably 10 to 30% by mass, and component (D) is 1 to 70% by mass, preferably 5 to 60% by mass, more preferably 10 to 50% by mass.

<Second composition>
The second composition of the present invention comprises the propylene-based polymer (A1), the ethylene/α-olefin copolymer (B), the propylene-based block copolymer (C), and the inorganic filler (D ) is a resin composition containing.

The propylene-based polymer (A1) used in the second composition of the present invention may be a propylene homopolymer or a random copolymer containing a monomer other than propylene as a copolymerization component.

The content of components (A1), (B), (C) and (D) in the second composition of the present invention is the sum of components (A1), (B), (C) and (D) of 100 In terms of % by mass, the component (A1) is 20 to 80% by mass, preferably 25 to 75% by mass, more preferably 30 to 70% by mass, and the component (B) is 1 to 50% by mass, preferably is 5 to 40% by mass, more preferably 10 to 30% by mass, component (C) is 1 to 20% by mass, preferably 2 to 15% by mass, more preferably 3 to 10% by mass, and component (D) is 1 to 70% by mass, preferably 5 to 60% by mass, more preferably 10 to 50% by mass.

<Third composition>
A third composition of the present invention is a resin composition containing the propylene-based polymer (A1) and the inorganic filler (D).

The propylene-based polymer (A1) used in the third composition of the present invention may be either a propylene homopolymer or a random copolymer.
The content of components (A1) and (D) in the third composition of the present invention is such that when the total of components (A1) and (D) is 100% by mass, component (A1) is 40 to 99% by mass. %, preferably 45 to 99% by mass, more preferably 50 to 99% by mass, and component (D) is 1 to 60% by mass, preferably 1 to 55% by mass, more preferably 1 to 50% by mass. be.

<Method for Producing Propylene-based Resin Composition>
The propylene-based resin composition of the present invention can be produced by blending the components described above. Each component may be added sequentially in any order, or may be mixed at the same time. Also, a multi-stage mixing method may be employed in which some components are mixed and then other components are mixed. However, for the first composition of the present invention, as described above, the propylene-based block copolymer (A1) and the propylene/α-olefin copolymer (A3) are mixed to form a propylene-based block copolymer. After forming (A2), the ethylene/α-olefin copolymer (B), the inorganic filler (D) and, if necessary, other components are mixed.

As a method of blending each component, for example, using a mixing device such as a Banbury mixer, a single screw extruder, a twin screw extruder, and a high speed twin screw extruder, each component is simultaneously or sequentially mixed or melt-kneaded. is mentioned.

[Molded body]
The molded article of the present invention is formed using the composition of the present invention described above. Since the composition of the present invention has high rigidity and low linear expansion, the molded article of the present invention exhibits small dimensional change due to temperature change and is excellent in dimensional stability. Therefore, the molded article of the present invention can be suitably used in various fields such as automobile parts, home appliance parts, food containers, and medical containers. Examples of the automobile parts include automobile interior and exterior members such as bumpers and instrument panels, and outer panel materials such as roofs, door panels, and fenders.
The method for molding the molded article of the present invention is not particularly limited, and various methods known as methods for molding polymers can be employed, but injection molding and press molding are particularly preferred.

EXAMPLES The present invention will be described in more detail below based on examples, but the present invention is not limited to these examples. Methods for measuring various physical properties described in Examples are as follows.

<Isotactic mesopentat fraction (mmmm))>
The isotactic mesopentad fraction mmmm [%], which is one of the indicators of the stereoregularity of a polymer and used to examine its microtacticity, is based on Macromolecules 8, 687 (1975) for propylene-based polymers. It was calculated from the peak intensity ratio of the assigned ¹³ C-NMR spectrum. The ¹³ C-NMR spectrum was measured using a JEOL EX-400 apparatus with TMS as a reference at a temperature of 130° C. and o-dichlorobenzene as a solvent.

<Temperature Rising Elution Fractionation Measurement (TREF)>
The amount of TREF high-temperature elution component, which is considered to be one of the stereoregularity indices, was calculated from the polymer concentration eluted at 122° C. or higher obtained by temperature-rising fractional measurement under the following conditions.
(Measurement condition)
Apparatus: Polymer Char CFC2 type cross fractionation chromatograph Detector: Polymer Char IR4 type infrared spectrophotometer (built-in)
Mobile phase: o-dichlorobenzene, BHT added Flow rate: 1.0 mL/min
Sample concentration: 90 mg/30 mL
Injection volume: 0.5 mL
Dissolution conditions: 145°C, 30min
Stabilization conditions: 135°C, 30min
Temperature drop rate: 1.0 mL/min
Elution division: -20°C to 0°C in 10°C increments, 0°C to 80°C in 5°C increments,
80°C to 104°C in 3°C increments, 104 to 126°C in 2°C increments Elution time: 3min

<Melting point>
The melting points of the components eluted at a temperature of 122° C. or higher by the temperature-rising elution fractionation measurement (TREF) were measured using a differential scanning calorimeter (DSC, manufactured by PerkinElmer) under the following conditions. The endothermic peak in the third step measured here was defined as the melting point (Tm).
(Measurement condition)
1st step: The temperature is raised to 240° C. at 10° C./min and held for 10 min.
2nd step: The temperature is lowered to 60°C at a rate of 10°C/min.
3rd step: The temperature is raised to 240°C at 10°C/min.

<Weight average molecular weight (Mw), number average molecular weight (Mn) and Z average molecular weight (Mz)>
The Mw/Mn value, which is an index of molecular weight distribution, and the Z-average molecular weight (Mz) were obtained by analyzing chromatograms measured under the following conditions by known methods.
(Measurement condition)
Apparatus: Gel permeation chromatograph Alliance GPC2000 type manufactured by Waters Column: TSKgel GMH6-HT x2 + TSKgel GMH6-HTL x2 manufactured by Tosoh
Mobile phase: o-dichlorobenzene (containing 0.025% BHT)
Flow rate: 1.0ml/min
Temperature: 140°C
Column calibration: Tosoh monodisperse polystyrene Sample concentration: 0.15% (w / v)
Injection volume: 0.4 ml

<Melt flow rate (MFR)>
Based on ASTM D1238E, the measurement temperature was 230° C. and the load was 2.16 kg.

<Flexural modulus>
The flexural modulus (MPa) was measured under the following conditions according to ISO 178.
(Measurement condition)
Temperature: 23°C
Test piece: 10 mm (width) x 4 mm (thickness) x 80 mm (length)
Bending speed: 2mm/min Span: 64mm

<Linear expansion coefficient>
The coefficient of linear expansion (10 ^-5 /°C) was evaluated by the TMA method (measurement range: -30 to 80°C). Specifically, the central part of a square plate with a length of 30 mm, a width of 30 mm, and a thickness of 2 mm was cut into a shape of 10 mm × 5 mm × 2 mm thickness and used as a test piece, and the injection molding flow direction and the direction perpendicular to the injection molding flow. The average value of the measured values was taken as the coefficient of linear expansion. The measurement conditions are as follows.
(Measurement condition)
Measuring device: TMA2940 (manufactured by TA)
Test load: 0.029N
Test temperature range: -30 to 80°C
Heating rate: 5°C/min
Annealing before test: 120°C x 30min

[Synthesis Example 1]
<Preparation of solid titanium (a-1)>
After sufficiently purging a high-speed stirring device with an internal volume of 2 liters (manufactured by Tokushu Kika Kogyo Co., Ltd.) with nitrogen, 700 ml of refined kerosene, 10 g of magnesium chloride, 24.2 g of ethanol and sorbitan distearate (manufactured by Kao Atlas Co., Ltd.) were added to the device. 3 g of Emsol 320") were charged. The system was heated under stirring and stirred for 30 minutes at 120° C. and 800 rpm. Under high-speed stirring, using a Teflon (registered trademark) tube with an inner diameter of 5 mm, the liquid was transferred to a 2-liter glass flask (equipped with a stirrer) filled with 1 liter of purified kerosene previously cooled to -10°C. The resulting solid was filtered and thoroughly washed with purified n-hexane to obtain a solid adduct in which 1 mol of magnesium chloride was coordinated with 2.8 mol of ethanol.

Then, the above solid adduct (45 millimoles in terms of magnesium atom) was suspended in 20 ml of decane, and the entire amount was introduced into 195 ml of titanium tetrachloride maintained at -20°C with stirring. The mixture was heated to 80° C. over 5 hours, and 1.8 ml (6.2 mmol) of diisobutyl phthalate was added. Subsequently, the temperature was raised to 110° C. and the mixture was stirred for 1.5 hours.

After completion of the reaction for 1.5 hours, the solid portion was collected by hot filtration and washed with decane at 100° C. and hexane at room temperature until titanium was no longer detected in the filtrate. Thus, solid titanium (a-1) containing 3.8% by mass of titanium, 16% by mass of magnesium, 18.2% by mass of diisobutyl phthalate, and 1.1% by mass of ethanol residues was obtained. Obtained.

<Preparation of solid titanium catalyst component (i-1)>
6.8 g of the obtained solid titanium (a-1), 113 ml of paraxylene, 11 ml of decane, 2.5 ml (23 mmol) of titanium tetrachloride and diisobutylphthalate were placed in a 200 ml glass reactor sufficiently purged with nitrogen. - 0.34 ml (1.2 mmol) was added. The temperature in the reactor was raised to 130° C., and the mixture was stirred at that temperature for 1 hour for contact treatment, and then the solid portion was collected by hot filtration. This solid portion was resuspended in 101 ml of paraxylene and 1.7 ml (15 mmol) of titanium tetrachloride and 0.22 ml (0.8 mmol) of diisobutyl phthalate were added.

Then, the temperature was raised to 130° C., and the mixture was stirred for 1 hour while maintaining the temperature to react. After completion of the reaction, solid-liquid separation was performed again by hot filtration, and the obtained solid portion was washed with decane at 100° C. and hexane at room temperature until the p-xylene in the catalyst was reduced to 1% by mass or less. Thus, a solid titanium catalyst component (i-1) containing 1.3% by mass of titanium, 20% by mass of magnesium and 13.8% by mass of diisobutyl phthalate was obtained.

<Preparation of prepolymerized catalyst (p-1)>
Into a nitrogen-purged 200 ml glass reactor, 50 ml of hexane, 2.5 mmol of triethylaluminum, 0.5 mmol of ethyl(diethylamino)dimethoxysilane, and the resulting solid titanium catalyst component (i-1) were added to titanium atoms. After charging 0.25 millimoles in conversion, propylene was supplied at a rate of 1.47 liters/hour for 1 hour while maintaining the temperature in the system at 20°C. By this operation, a prepolymerized catalyst (p-1) in which 3 g of propylene was prepolymerized per 1 g of the solid titanium catalyst component (i-1) was obtained.

<Main polymerization>
An autoclave having an inner volume of 2 liters was charged with 500 g of propylene and 3.5 liters of hydrogen, and the temperature in the system was raised to 60°C. Thereafter, 0.7 mmol of triethylaluminum, 0.7 mmol of ethyl(diethylamino)dimethoxysilane, and 0.0028 mmol of the prepolymerized catalyst (p-1) obtained above in terms of titanium atoms were added to initiate polymerization. started. Polymerization was carried out for 1 hour while the temperature in the system was maintained at 70°C. Then, ethanol was added to terminate the polymerization, and unreacted propylene was purged to obtain 286 g of propylene homopolymer (A1-1). Table 1 shows the results of evaluating the physical properties of the obtained propylene homopolymer (A1-1).

[Synthesis Example 2]
In Synthesis Example 1, the procedure was carried out in the same manner as in Synthesis Example 1 except that the charged amount of hydrogen in the main polymerization was changed to 8.5 liters. Table 1 shows the evaluation results of the physical properties of the obtained propylene homopolymer (A1-2).

[Synthesis Example 3]
In Synthesis Example 1, the procedure was carried out in the same manner as in Synthesis Example 1, except that the charged amount of hydrogen in the main polymerization was changed to 9 liters. Table 1 shows the evaluation results of the physical properties of the obtained propylene homopolymer (A1-3).

[Comparative Synthesis Example 1]
In Synthesis Example 1, diethylaminotriethoxysilane was used in place of the ethyl(diethylamino)dimethoxysilane used in the preparation of the prepolymerization catalyst (p-1) and the main polymerization, and the amount of hydrogen charged was 1.8 liters. The procedure was carried out in the same manner as in Synthesis Example 1, except that it was changed to Table 1 shows the evaluation results of the physical properties of the obtained propylene homopolymer (a-1).

[Comparative Synthesis Example 2]
Comparative synthesis example 1 was carried out in the same manner as in comparative synthesis example 1 except that the amount of hydrogen charged in the main polymerization was changed to 4.5 liters. Table 1 shows the evaluation results of the physical properties of the obtained propylene homopolymer (a-2).

[Comparative Synthesis Example 3]
Comparative synthesis example 1 was carried out in the same manner as in comparative synthesis example 1, except that the amount of hydrogen charged in the main polymerization was changed to 5 liters. Table 1 shows the evaluation results of the physical properties of the obtained propylene homopolymer (a-3).

The meanings of the symbols related to "external donor" in "olefin polymerization catalyst" in Table 1 are as follows.
ii-1: Ethyl (diethylamino) dimethoxysilane
ii-2: Diethylaminotriethoxysilane Components (A3) and (B) to (D) used in the following examples and comparative examples are as follows.
・Propylene/α-olefin copolymer (A3): Propylene/ethylene copolymer (trade name: Toughmer S4020, manufactured by Mitsui Chemicals, Inc.)
Ethylene/α-olefin copolymer (B): ethylene/butene copolymer (trade name: Toughmer A1050S, manufactured by Mitsui Chemicals, Inc.)
- Propylene-based block copolymer (C): propylene/ethylene block copolymer (trade name: X855, manufactured by Prime Polymer Co., Ltd.)
・ Inorganic filler (D)
D-1: Talc (trade name: JM209, manufactured by Asada Flour Milling Co., Ltd.)
D-2: Talc (trade name: HAR 3G77, manufactured by IMERYS)

[Examples 1 and 2 and Comparative Examples 1 and 2]
First, the propylene homopolymer obtained in the above Synthesis Example or Comparative Synthesis Example and the propylene/α-olefin copolymer (A3) were mixed in the amounts shown in Table 2, and then extruded using a twin-screw extruder as follows. A propylene-based block copolymer was prepared by melt-kneading under the conditions of Next, the obtained propylene-based block copolymer was blended with the ethylene/α-olefin copolymer (B) and the inorganic filler (D) in the amounts shown in Table 2, and extruded with a twin-screw extruder under the following conditions. to prepare a pellet-shaped propylene-based resin composition. The obtained pellets were injection-molded with an injection molding machine under the following conditions to prepare test pieces. Table 2 shows the physical properties of the obtained injection molded article (test piece).

<Melt-kneading conditions>
Co-rotating twin-screw kneader: Product number KZW-15, manufactured by Technobell Co., Ltd. Kneading temperature: 190°C
Screw rotation speed: 500 rpm
Feeder rotation speed: 40 rpm
<Injection molding conditions>
Injection molding machine: EC40 (trade name, manufactured by Toshiba Machine Co., Ltd.)
Cylinder temperature: 190°C
Mold temperature: 40°C
Injection time - holding pressure time: 13 seconds Cooling time: 15 seconds

[Example 3 and Comparative Examples 3-4]
The propylene homopolymer, the ethylene/α-olefin copolymer (B), the propylene-based block copolymer (C), and the inorganic After mixing the filler (D), the mixture was melt-kneaded with a twin-screw extruder under the following conditions to prepare a pellet-shaped propylene-based resin composition. The obtained pellets were injection-molded with an injection molding machine under the following conditions to prepare test pieces. Table 3 shows the physical properties of the obtained injection molded article (test piece).

<Melt-kneading conditions>
Co-rotating twin-screw kneader: Product number KZW-15, manufactured by Technobell Co., Ltd. Kneading temperature: 190°C
Screw rotation speed: 500 rpm
Feeder rotation speed: 40 rpm
<Injection molding conditions>
Injection molding machine: EC40 (trade name, manufactured by Toshiba Machine Co., Ltd.)
Cylinder temperature: 190°C
Mold temperature: 40°C
Injection time - holding pressure time: 13 seconds Cooling time: 15 seconds

[Examples 4-5 and Comparative Examples 5-6]
The propylene homopolymer obtained in the Synthesis Example or Comparative Synthesis Example and the inorganic filler (D) were mixed so as to have the composition shown in Table 4, and then melt-kneaded in a twin-screw extruder under the following conditions. Thus, a pellet-shaped propylene-based resin composition was produced. The obtained pellets were injection-molded with an injection molding machine under the following conditions to prepare test pieces. Table 4 shows the physical properties of the obtained injection molded product (test piece).

<Melt-kneading conditions>
Co-rotating twin-screw kneader: Product number KZW-15, manufactured by Technobell Co., Ltd. Kneading temperature: 190°C
Screw rotation speed: 500 rpm
Feeder rotation speed: 40 rpm
<Injection molding conditions>
Injection molding machine: EC40 (trade name, manufactured by Toshiba Machine Co., Ltd.)
Cylinder temperature: 190°C
Mold temperature: 40°C
Injection time - holding pressure time: 13 seconds Cooling time: 15 seconds

Claims (7)

A propylene-based polymer (A1) that satisfies the following requirements (1) to (4), and a propylene-based block copolymer (A2) composed of a propylene homopolymer portion and a propylene/α-olefin copolymer portion. 20 to 99% by mass of at least one component (A) selected from the group,
Ethylene/α-olefin copolymer containing 50 to 95 mol% of structural units derived from ethylene and 5 to 50 mol% of structural units derived from α-olefin having 3 to 20 carbon atoms (B) 0 to 50 mass%,
0 to 20% by mass of a propylene block copolymer (C) different from the propylene block copolymer (A2), and 1 to 70% by mass of an inorganic filler (D)
(where the total of components (A), (B), (C) and (D) is 100% by mass),
The propylene -based block copolymer (A2) is
60 to 99% by mass of the propylene-based polymer (A1) as the propylene homopolymer portion, and 55 to 90% by mol of structural units derived from propylene as the propylene/α-olefin copolymer portion and other than propylene 1 to 40% by mass of a propylene/α-olefin copolymer (A3) containing 10 to 45 mol% of a structural unit derived from an α-olefin having 2 to 20 carbon atoms (provided that component (A1) and The total of (A3) is 100% by mass.), propylene-based resin composition:
(1) Melt flow rate (MFR) (ASTM D1238, 230° C., under 2.16 kg load) is 0.5 to 1000 g/10 minutes;
(2) When the proportion of components eluted at a temperature of 122°C or higher by the temperature programmed elution fractionation method (TREF) is A% by mass, and the melt flow rate of the requirement (1) is Bg/10 minutes, the following formula fulfill (I);
100≧A≧8.0×EXP(−0.01×B) (I)
(3) the isotactic mesopentat fraction (mmmm) is higher than 98.0% and not higher than 99.9%;
(4) The ratio (Mw/Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) measured by gel permeation chromatography (GPC) is 4.2-20. The propylene-based resin composition according to claim 1, wherein the propylene-based polymer (A1) further satisfies the following requirement (5):
(5) The Z-average molecular weight (Mz) of components eluted at a temperature of 122° C. or higher by temperature programmed elution fractionation (TREF) is 300,000 to 5,000,000 as measured by gel permeation chromatography (GPC). The isotactic mesopentat fraction (mmmm) of the requirement (3) is 98.4% or more and 99.9% or less,
The propylene-based resin composition according to claim 1 or 2, wherein the ratio (Mw/Mn) of the requirement (4) is 4.5-10. 20 to 90% by mass of the propylene-based block copolymer (A2),
1 to 30% by mass of the ethylene/α-olefin copolymer (B), and
The inorganic filler (D) 1 to 70% by mass
(where the total of components (A2), (B) and (D) is 100% by mass), the propylene-based resin composition according to any one of claims 1 to 3. 30 to 80% by mass of the propylene-based polymer (A1),
1 to 50% by mass of the ethylene/α-olefin copolymer (B),
1 to 20% by mass of the propylene-based block copolymer (C), and
The inorganic filler (D) 1 to 60 mass%
(where the total of components (A1), (B), (C) and (D) is 100% by mass), the propylene-based resin composition according to any one of claims 1 to 3 . 40 to 99% by mass of the propylene-based polymer (A1), and
The inorganic filler (D) 1 to 60 mass%
(where the total of components (A1) and (D) is 100% by mass),
The propylene-based resin composition according to any one of claims 1 to 3, wherein the melt flow rate of requirement (1) is 100 to 1000 g/10 minutes. A molded article formed using the propylene-based resin composition according to any one of claims 1 to 6 .