JP6884061B2 - Polypropylene resin composition and injection compression molded product - Google Patents

Description

The present invention relates to a polypropylene resin composition and an injection compression molded article.

Polypropylene-based resin compositions containing polypropylene as a main component are used in various applications because they are inexpensive and have excellent mechanical properties such as rigidity. In particular, polypropylene-based resin compositions containing rubber components such as ethylene-α-olefin copolymer elastomers have excellent impact resistance, and are therefore widely used in various fields such as automobile interior materials, daily necessities, and housings for electrical products. It is used.
In recent years, polypropylene-based resin compositions have been required to further improve the balance between rigidity and impact resistance of molded products, especially in the field of automobile interior materials. When the molded product is manufactured by an injection molding method or an injection compression molding method, high fluidity during molding is also required.

The following (1) to (4) have been proposed as polypropylene-based resin compositions suitable for an injection molding method or an injection compression molding method.
(1) A propylene-based resin composition in which a specific propylene / ethylene-block copolymer, a specific ethylene / α-olefin copolymer rubber, a hindered amine compound, and if necessary, a nucleating agent and talc are blended in a specific ratio. Product (Patent Document 1).
(2) A propylene-based resin composition in which a specific propylene / ethylene-block copolymer, talc, a specific ethylene / α-olefin copolymer rubber, and polyethylene are mixed in a specific ratio as needed (Patent Documents). 2).
(3) A propylene-based resin composition in which two specific types of propylene / ethylene-block copolymer and talc are blended in a specific ratio (Patent Document 3).
(4) A polypropylene-based resin having a specific MFR obtained by heat-treating a resin composition of a propylene polymer, an ethylene-α-olefin copolymer, a phosphite ester, and an organic peroxide in a specific ratio. Composition (Patent Document 4).

Japanese Unexamined Patent Publication No. 11-315186 Japanese Unexamined Patent Publication No. 2001-72828 Japanese Unexamined Patent Publication No. 2003-55529 JP-A-2010-65216

In the injection compression molding method, the molding material is injected into the mold at a lower pressure than in the injection molding method, so that the molding material is required to have higher fluidity. The fluidity of the propylene-based resin composition of (1) is not sufficient for use in injection compression molding.
It cannot be said that the molded product of the propylene-based resin composition of (2) and (3) has a sufficient balance between rigidity and impact resistance. In addition, since these propylene-based resin compositions contain a large amount of talc for the purpose of reducing gloss and improving rigidity, there are problems such as a large specific gravity of the molded product and low scratch resistance. is there.
The polypropylene-based resin composition of (4) is not considered for application to the injection compression molding method. Further, since this polypropylene-based resin composition is bis-breaked (cutting the molecular chain of the propylene polymer, etc.) by heat treatment in the presence of an organic peroxide, it is inferior in rigidity, and has rigidity and impact resistance. The balance is not enough.

An object of the present invention is to provide a polypropylene-based resin composition capable of obtaining a molded product having high fluidity during molding and an excellent balance between rigidity and impact resistance, and an injection compression molded product using the same.

The present invention has the following aspects.
[1] Component (A): Consists of a homopolypropylene component and an ethylene-propylene copolymer component, has a melt mass flow rate of 80 to 110 g / 10 minutes at 230 ° C. and 21.18 N, and is a xylene-soluble component. The ultimate viscosity is 2.3 to 2.9 dL / g, the molecular weight distribution (Mw / Mn) of the xylene insoluble matter is 4.0 to 8.0, and the content of the ethylene-propylene copolymer component is the said. It is 13 to 20% by mass with respect to the total mass of polypropylene, and the propylene content of the ethylene-propylene copolymer component is more than 69% by mass and 79% by mass or less with respect to the total mass of the ethylene-propylene copolymer component. With a certain polypropylene
(B) Component: An ethylene-α-olefin copolymer having 4 to 8 carbon atoms of α-olefin, having a melt mass flow rate of 1 to 4 g / 10 minutes at 230 ° C. and 21.18 N, and having a density of 1 to 4 g / 10 minutes. With an elastomer of 0.847 to 0.873 g / cm ^3,
(C) Ingredients: talc and
Including
When the total mass of the component (A), the component (B) and the component (C) is 100% by mass, the content of the component (A) is 78 to 89% by mass, and the component (B) The content of the component (C) is 4 to 9% by mass, and the content of the component (C) is 7 to 13% by mass.
A polypropylene-based resin composition having a melt mass flow rate of 69 to 100 g / 10 minutes at 230 ° C. and 21.18 N in the entire composition.
[2] Component (D): Further containing magnesium stearate,
The content of the component (D) is 0.05 to 1 part by mass with respect to a total of 100 parts by mass of the component (A), the component (B) and the component (C). Polypropylene resin composition.
[3] An injection compression molded product made of the polypropylene-based resin composition according to [1] or [2].
[4] The injection compression molded article according to [3], which is used for automobile interiors.

The polypropylene-based resin composition of the present invention has high fluidity during molding. Further, according to the polypropylene-based resin composition of the present invention, a molded product having an excellent balance between rigidity and impact resistance can be obtained.
The injection compression molded product of the present invention has an excellent balance between rigidity and impact resistance. It also has low gloss.

The polypropylene-based resin composition of the present invention (hereinafter, also referred to as “the present resin composition”) contains the following component (A), the following component (B), and the following component (C).
The present resin composition may further contain the following component (D).
The present resin composition may further contain components other than the above components (A) to (D).

The melt mass flow rate (MFR) of the entire composition of the present resin composition is 69 to 100 g / 10 minutes, preferably 70 to 100 g / 10 minutes, and particularly preferably 70 to 90 g / 10 minutes. When the MFR of the entire composition is at least the lower limit of the above range, the fluidity of injection compression molding at the molding temperature (for example, 200 to 240 ° C.) is sufficiently high, and it is useful as a material for injection compression molding. When the MFR of the entire composition is not more than the upper limit of the above range, the balance between the rigidity and the impact resistance of the molded product is excellent.

The MFR of the entire composition is a value at 230 ° C. and 21.18 N (2.16 kgf). Hereinafter, unless otherwise specified, MFR shall show a value at 230 ° C. and 21.18N.
MFR is measured according to JIS K 7210-1: 2014 (and so on).
The MFR of the entire composition can be adjusted by the content of each of the components (A) to (D), the MFR of each of the components (A) to (B), and the like.

<Ingredient (A)>
The component (A) is polypropylene that satisfies the following (i) to (vi). The component (A) is a base material component of the present resin composition.
(I) It is composed of a homopolypropylene component and an ethylene-propylene copolymer component.
(Ii) The melt mass flow rate (hereinafter, also referred to as “MFR”) at 230 ° C. and 21.18 N is 80 to 110 g / 10 minutes.
(Iii) The ultimate viscosity of the xylene-soluble component is 2.3 to 2.9 dL / g.
(Iv) The Mw / Mn of the insoluble xylene is 4.0 to 8.0.
(V) The content of the ethylene-propylene copolymer component is 13 to 20% by mass with respect to the total mass of the polypropylene.
(Vi) The propylene content of the ethylene-propylene copolymer component is more than 69% by mass and 79% by mass or less with respect to the total mass of the ethylene-propylene copolymer component.

Polypropylene composed of a homopolypropylene component and an ethylene-propylene copolymer component is a kind of polypropylene which is also called a heterophasic copolymer, a heterophasic polypropylene, or a block polypropylene. The ethylene-propylene copolymer component is an elastomer component.
The component (A) may be a chemically bonded product of the homopolypropylene component and the ethylene-propylene copolymer component, and is simply a blend of the homopolypropylene component and the ethylene-propylene copolymer component. May be good.
The component (A) is obtained by polymerizing ethylene and propylene, and if necessary, other monomers in the presence of homopolypropylene. The method for producing the component (A) will be described in detail later.

The homopolypropylene component is typically a crystalline homopolypropylene component.
The crystalline homopolypropylene component is a homopolypropylene having high stereoregularity, and a melting point peak is observed when measured by DSC (Differential Scanning Calorimetry) at a heating rate of 10 ° C./min. ..

The ethylene-propylene copolymer component consists of an ethylene unit and a propylene unit.
The propylene content of the ethylene-propylene copolymer component (content ratio of propylene unit, hereinafter also referred to as "PC") is more than 69% by mass and 79% by mass or less with respect to the total mass of the ethylene-propylene copolymer component. , 70-75% by mass is preferable. When the PC is within the above range, the balance between the rigidity of the component (A) and the impact resistance is excellent.
PC is ^{measured by the 13} C-NMR (Nuclear Magnetic Resonance) method.

The MFR of the component (A) is 80 to 110 g / 10 minutes, preferably 85 to 110 g / 10 minutes. When the MFR of the component (A) is equal to or higher than the lower limit of the above range, the MFR of the present resin composition is likely to be equal to or higher than the lower limit of the above range. When the MFR of the component (A) is not more than the upper limit of the above range, the impact resistance and production stability of the component (A) are excellent.
The MFR of the component (A) can be adjusted by adjusting the MFR of the homopolypropylene component, the content of the ethylene-propylene copolymer component, and the like. The MFR of the homopolypropylene component can be adjusted by the molecular weight of the homopolypropylene component. The molecular weight of the homopolypropylene component can be adjusted by the concentration of hydrogen at the time of polymerization.

The content of the ethylene-propylene copolymer component in the component (A) (hereinafter, also referred to as “BIPO”) is 13 to 20% by mass and 14 to 16% by mass with respect to the total mass of the component (A). Is preferable. When BIPO is at least the lower limit of the above range, the impact resistance and the manufacturing cost of the composition are excellent. If the BIPO is not more than the upper limit of the above range, the rigidity is excellent.
BIPO is ^{measured by 13} C-NMR method.

The ultimate viscosity of the xylene-soluble component (A) (hereinafter, also referred to as “XSIV”) is 2.3 to 2.9 dL / g, preferably 2.4 to 2.8 dL / g. XSIV can be regarded as the ultimate viscosity of the ethylene-propylene copolymer component in the component (A). When XSIV is at least the lower limit of the above range, the impact resistance is excellent. When XSIV is not more than the upper limit value in the above range, the surface impact resistance is excellent among the impact resistance.
XSIV is a measured value in tetrahydronaphthalene at 135 ° C.

The molecular weight distribution (Mw / Mn) of the xylene insoluble component (hereinafter, also referred to as “XI”) of the component (A) is 4.0 to 8.0, preferably 4.5 to 7.0. XI is a crystalline component in the component (A). Mw / Mn of XI can be regarded as the molecular weight distribution of the crystalline component. When Mw / Mn of XI is equal to or higher than the lower limit of the above range, the rigidity is excellent. When Mw / Mn of XI is not more than the upper limit value of the above range, the impact resistance, particularly the surface impact resistance is excellent.
Mw / Mn of XI is a value obtained by dividing the mass average molecular weight (Mw) of XI measured by gel permeation chromatography (GPC) by the number average molecular weight (Mn). Mw and Mn of XI are values converted into propylene-based polymers after calibration using standard polystyrene, respectively.

<Ingredient (B)>
The component (B) is an elastomer satisfying the following (vii) to (iv). The component (B) contributes to the improvement of the impact resistance of the molded product.
(Vii) An ethylene-α-olefin copolymer having 4 to 8 carbon atoms of the α-olefin.
(Viii) MFR is 1 to 4 g / 10 minutes.
(Iv) The density is 0.847 to 0.873 g / cm ³ .

The ethylene-α-olefin copolymer has an ethylene unit and an α-olefin unit having 4 to 8 carbon atoms.
Examples of the α-olefin having 4 to 8 carbon atoms include 1-butene, 1-pentene, 1-hexene, 1-octene, 4-methyl-1-pentene and the like, and 1-butene and 1-octene are preferable. ..
The ethylene-α-olefin copolymer may further have a monomer unit other than the ethylene unit and the α-olefin unit as long as the characteristics of the ethylene-α-olefin copolymer are not impaired. Examples of other monomers include diene and the like.

The MFR of the component (B) is 1 to 4 g / 10 minutes, preferably 1.5 to 3 g / 10 minutes. When the MFR of the component (B) is equal to or higher than the lower limit of the above range, the MFR of the present resin composition is likely to be equal to or higher than the lower limit of the above range. When the MFR of the component (B) is not more than the upper limit of the above range, the impact resistance of the molded product is excellent.

The density of the component (B) is a ^{0.847~0.873g / cm 3, 0.850~0.872g / cm} 3 are preferred. When the density of the component (B) is equal to or higher than the lower limit of the above range, the rigidity is excellent. When the density of the component (B) is not more than the upper limit of the above range, the impact resistance is excellent.
Density is measured by JIS K 7112: 1999.

<Ingredient (C)>
The component (C) is talc. The component (C) functions as a crystal nucleating agent that promotes the formation of polypropylene crystal nuclei in addition to the effect of improving the rigidity of a single substance, and contributes to the improvement of the rigidity of the molded product.
The average particle size of the component (C) is preferably 1 to 10 μm, more preferably 3 to 7 μm. The average particle size is measured according to JIS Z 8825.

<Ingredient (D)>
The component (D) is magnesium stearate. The component (D) contributes to the improvement of impact resistance and fluidity (MFR) of the molded product. The component (D) also functions as a lubricant, but in the case of a lubricant other than the component (D), the effect of improving the impact resistance is not seen.

<Other ingredients>
Other components include, for example, antioxidants, chlorine absorbers, heat stabilizers, light stabilizers (lightproofing agents), UV absorbers, internal lubricants, external lubricants, antiblocking agents, antistatic agents, antifogging agents, etc. Additives such as crystal nucleating agents, flame retardants, dispersants, copper damage inhibitors, neutralizing agents, plasticizers, foaming agents, bubble inhibitors, cross-linking agents, peroxides, oil spreads and pigments (organic or inorganic) Can be mentioned. The amount of each additive added may be a known amount.

<Contents of each component>
In this resin composition, when the total mass of the component (A), the component (B) and the component (C) is 100% by mass, the content of the component (A) is 78 to 89% by mass. %, The content of the component (B) is 4 to 9% by mass, the content of the component (C) is 7 to 13% by mass, and the content of the component (A) is 80 to 85% by mass. It is preferable that the content of the component (B) is 5 to 8% by mass and the content of the component (C) is 8 to 12% by mass.
If the content of the component (A) is not less than the lower limit of the above range, the manufacturing cost and manufacturing stability are excellent, and if it is not more than the upper limit of the above range, the effects of the components (B) and (C) are sufficient. It is demonstrated in. When the content of the component (B) is at least the lower limit of the above range, the impact resistance of the molded product is excellent, and when it is at least the upper limit of the above range, the rigidity of the molded product is excellent. If the content of the component (C) is at least the lower limit of the above range, the rigidity of the molded product is excellent, and if it is at least the upper limit of the above range, the specific gravity is sufficiently low, so that the weight of the molded product can be reduced. The scratch resistance of the molded product is also good.

When the present resin composition contains the component (D), the content of the component (D) is 0.05 to 1 with respect to a total of 100 parts by mass of the component (A), the component (B) and the component (C). By mass is preferable, and 0.1 to 0.4 parts by mass is particularly preferable. When the content of the component (D) is at least the lower limit of the above range, the impact resistance and fluidity of the molded product are more excellent. When the content of the component (D) is not more than the upper limit of the above range, the component (D) is less likely to bleed out to the surface of the molded product, and the surface texture of the molded product is more excellent.

<Manufacturing method of polypropylene resin composition>
Examples of the method for producing the present resin composition include a method of mixing the component (A), the component (B), and the component (C). If necessary, any one or more of the component (D) and the other components may be further mixed. There is no limitation on the order of addition of each component.
The mixing method is not particularly limited, and examples thereof include a method using a mixer such as a Henschel mixer or a tumbler mixer.
After mixing, the obtained mixture may be melt-kneaded and further pelletized. As the melt-kneading device, a single-screw extruder, a twin-screw extruder, a Banbury mixer, a kneader, a roll mill, or the like can be used.
As the components (A) to (D) and other components, if a commercially available product is available, a commercially available product may be used. Those manufactured by a known manufacturing method may be used.

(Method for manufacturing component (A))
Examples of the method for producing the component (A) include a method of polymerizing ethylene and propylene in the presence of homopolypropylene, and if necessary, other monomers. The polymerization produces an ethylene-propylene copolymer (including ethylene units, propylene units and, if necessary, other monomer units), and the component (A) is obtained as a polymerization product. By carrying out the polymerization in the presence of homopolypropylene, the production range of the ethylene-propylene copolymer is expanded. Further, since the dispersibility of the copolymer is increased, the balance between rigidity and impact resistance is improved.

As a method for producing the component (A), a multi-stage polymerization method is typically used. For example, in the first-stage polymerization reactor of a polymerization apparatus equipped with a two-stage polymerization reactor, propylene is polymerized to obtain homopolypropylene, and the obtained homopolypropylene is supplied to the second-stage polymerization reactor. The component (A) can be obtained by polymerizing ethylene and propylene and, if necessary, other monomers in this second-stage polymerization reactor.
The polymerization conditions may be the same as the known polymerization conditions. For example, as the first-stage polymerization condition, a slurry polymerization method in which propylene is in a liquid phase and has high monomer density and productivity can be mentioned. Examples of the second-stage polymerization condition include a vapor phase polymerization method in which a copolymer having high solubility in propylene can be easily produced.
Polymerization (polymerization of propylene, polymerization of ethylene, propylene, etc.) is usually carried out using a catalyst. At the time of polymerization, hydrogen may be added to adjust the molecular weight, if necessary.
Prior to the polymerization in the first-stage polymerization reactor, propylene may be prepolymerized in order to form a polymer chain as a foothold for the subsequent main polymerization in the solid catalyst component. Prepolymerization is usually carried out at 40 ° C. or lower, preferably 30 ° C. or lower, and more preferably 20 ° C. or lower.

As the catalyst, a known olefin polymerization catalyst can be used.
As the catalyst, a stereospecific Ziegler-Natta catalyst is preferable, and the following catalyst (I) is particularly preferable.
Catalyst (I): A catalyst containing a solid catalyst containing magnesium, titanium, halogen and an electron donor compound, an organoaluminum compound, and an external electron donor compound.

Examples of the electron donor compound (also referred to as “internal electron donor compound”) in the solid catalyst include phthalate compounds, succinate compounds, and diether compounds. A phthalate compound is preferable because the obtained polypropylene has high stereoregularity and the molecular weight distribution (Mw / Mn) of the xylene insoluble component (A) of the present invention can be easily controlled within a predetermined range. Examples of the phthalate compound include dimethylphthalate, diethylphthalate, dibutylphthalate, diisobutylphthalate, diisopropylphthalate, dioctylphthalate and the like.

Examples of the organic aluminum compound include trialkylaluminum such as triethylaluminum and triisobutylaluminum, trialkenylaluminum such as triisoprenylaluminum, dialkylaluminum alkoxide such as diethylaluminum ethoxide and dibutylaluminum butoxide, and ethylaluminum sesquiethoxydo. In addition to alkylaluminum sesquialkoxides such as butylaluminum sesquibutoxide, R ⁷ _2.5 Al (OR ⁸ ) _0.5 (R ⁷ , R ⁸ are hydrocarbon groups that may be different or the same, respectively. ), Partially alkoxylated alkylaluminum, diethylaluminum chloride, dibutylaluminum chloride, dialkylaluminum halogenide such as diethylaluminum bromide, ethylaluminum sesquichloride, butylaluminum sesquichloride, ethylaluminum sesqui Partially halogenated alkylaluminum such as alkylaluminum sesquihalogenide such as bromide, ethylaluminum dichloride, propylaluminum dichloride, alkylaluminum dihalogenide such as butylaluminum dibromide, diethylaluminum hydride, dialkyl such as dibutylaluminum hydride. Partially hydrided alkylaluminum such as aluminum hydride, ethylaluminum dihydride, alkylaluminum dihydride such as propylaluminum dihydride, ethylaluminum ethoxychloride, butylaluminum butokicyclolide, partially alkoxy such as ethylaluminum ethoxybromid Examples thereof include alkylaluminum that has been converted and halogenated.

External electron donor compounds typically include organosilicon compounds. Preferred organic silicon compounds include, for example, trimethylmethoxysilane, trimethylethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, diisopropyldimethoxysilane, t-butylmethyldimethoxysilane, t-butylmethyldiethoxysilane, t-amylmethyldiethoxy. Silane, diphenyldimethoxysilane, phenylmethyldimethoxysilane, diphenyldiethoxysilane, biso-tolyldimethoxysilane, bism-tolyldimethoxysilane, bisp-tolyldimethoxysilane, bisp-tolyldiethoxysilane, bisethylphenyldimethoxysilane , Dicyclopentyl dimethoxysilane, dicyclohexyldimethoxysilane, cyclohexylmethyldimethoxysilane, cyclohexylmethyldiethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, vinyltrimethoxysilane, methyltrimethoxysilane, n-propyltriethoxysilane, decyltri Methoxysilane, decyltriethoxysilane, phenyltrimethoxysilane, γ-chloropropyltrimethoxysilane, methyltriethoxysilane, ethyltriethoxysilane, vinyltriethoxysilane, t-butyltriethoxysilane, texyltrimethoxysilane, n -Butyltriethoxysilane, iso-butyltriethoxysilane, phenyltriethoxysilane, γ-aminopropyltriethoxysilane, chlortriethoxysilane, ethyltriisopropoxysilane, vinyltributoxysilane, cyclohexyltrimethoxysilane, cyclohexyltriethoxy. Silane, 2-norbornantrimethoxysilane, 2-norbornantriethoxysilane, 2-norbornanmethyldimethoxysilane, ethyl silicate, butyl silicate, trimethylphenoxysilane, methyltriallyloxysilane, vinyltris (β-methoxyethoxysilane) ), Vinyltriacetoxysilane, dimethyltetraethoxydisiloxane and the like.

The method for obtaining the component (A) by the multi-stage polymerization method is not limited to the above method, and homopolypropylene may be polymerized in a plurality of polymerization reactors, or an ethylene-propylene copolymer may be polymerized in a plurality of polymerization reactions. It may be polymerized in a vessel.
As a method of obtaining the component (A), there is also a method of using a polymerizer having a gradient of monomer concentration and polymerization conditions. In such a polymerizer, for example, one in which at least two polymerization regions are bonded can be used, and the monomer can be polymerized by vapor phase polymerization. Specifically, in the presence of a catalyst, a monomer is supplied and polymerized in a polymerization region consisting of an ascending tube, and a monomer is supplied and polymerized by a descending tube connected to the ascending tube. The polymerization product is recovered while circulating. This method comprises means to prevent the gas mixture present in the ascending tube from entering the descending tube in whole or in part. Further, a gas and / or liquid mixture having a composition different from that of the gas mixture existing in the rising pipe is introduced into the falling pipe. As this polymerization method, for example, the method described in JP-A-2002-520426 can be applied.
The polymerization temperature is preferably 50 to 90 ° C, more preferably 60 to 90 ° C, still more preferably 70 to 90 ° C. When the polymerization temperature is at least the lower limit of the above range, the productivity and the stereoregularity of the obtained polypropylene are more excellent.
The polymerization pressure is preferably 25 to 60 bar (2.5 to 6.0 MPa), more preferably 33 to 45 bar (3.3 to 4.5 MPa) when it is carried out in the liquid phase. When it is carried out in the gas phase, it is preferably 5 to 30 bar (0.5 to 3.0 MPa), more preferably 8 to 30 bar (0.8 to 3.0 MPa).

<Effect>
In this resin composition, since the components (A) to (C) are contained in a specific ratio, the fluidity at the time of molding is high. Further, the molded product obtained by molding the present resin composition has an excellent balance between rigidity and impact resistance.
That is, by combining the component (A), which is the base material component, with the component (B), which is an elastomer component, the impact resistance is further enhanced, and by combining the component (C), the rigidity is further enhanced, and the impact resistance is further enhanced. And the balance of rigidity becomes better. By containing a certain amount of the component (C), it is possible to give appropriate rigidity as a product. Further, since the MFR of the component (A) itself is relatively high, it exhibits high fluidity during molding. When the component (D) is further contained, the fluidity is further enhanced.
The fluidity of the present resin composition is sufficiently high for injection compression molding. For example, even when a thin-walled molded product is obtained by injection compression molding, molding defects called short shots, in which the resin composition does not spread over a part of the mold cavity, are unlikely to occur. Therefore, this resin composition is useful as a material for injection compression molding.

[Injection compression molded product]
The injection compression molded product of the present invention comprises the present resin composition.
The injection compression molded product of the present invention can be obtained by injection compression molding the resin composition.
Injection compression molding of the present resin composition can be performed by a known method.
The injection compression molded product of the present invention can be used, for example, as an automobile interior material, daily necessities, a housing for electric appliances, a food packaging container, and the like. In particular, an automobile interior material is suitable in terms of low gloss.

Examples and comparative examples are shown below, but the present invention is not limited to the following examples.
The measurement methods and materials used in this example are shown below.

〔Measuring method〕
<MFR>
MFR was measured according to JIS K 7210-1: 2014 under the conditions of a temperature of 230 ° C. and a load of 21.18 N.

<Density>
Density was measured according to JIS K 7112: 1999.

<Total ethylene content of polypropylene>
For a sample dissolved in a mixed solvent of 1,2,4-trichlorobenzene / benzene dehydride, Bruker's AVANCE III HD400 ( ¹³ C resonance frequency 100 MHz) was used, the measurement temperature was 120 ° C, the flip angle was 45 degrees, and the pulse interval was 7. ^{A 13} C-NMR spectrum was obtained under the conditions of seconds, sample rotation speed of 20 Hz, and integration number of 5000 times.
Using the spectrum obtained above, the total ethylene content (mass) of polypropylene by the method described in the literature of Kakugo, Y.Naito, K.Mizunuma and T.Miyatake, Macromolecules, 15, 1150-1152 (1982). %) Was asked.

<Propylene content (mass%) of ethylene-propylene copolymer component>
The same method as the total ethylene content, except that the integrated strength T'ββ obtained by the following formula was used instead of the integrated strength of Tββ obtained when measuring the total ethylene content of polypropylene by the method described in the above document. The ethylene content (% by mass) in the ethylene-propylene copolymer component was determined.
T'ββ = 0.98 × Sαγ × A / (1-0.98 × A)
Here, A = Sαγ / (Sαγ + Sαδ), which is calculated from Sαγ and Sαδ described in the above document.
The propylene content (PC) of the ethylene-propylene copolymer component is calculated by "ethylene content in the 100-ethylene-propylene copolymer component".

<Content of ethylene-propylene copolymer component in polypropylene>
The content (BIPO) of the ethylene-propylene copolymer component with respect to the total mass of polypropylene was calculated by the following formula.
Content of ethylene-propylene copolymer component (% by mass) = total ethylene content of polypropylene / (ethylene content in ethylene-propylene copolymer component / 100)

<Ultimate viscosity of xylene-soluble polypropylene>
The xylene-soluble component of polypropylene was obtained by the following method, and the ultimate viscosity (XSIV) of the xylene-soluble component was measured.
2.5 g of a polypropylene sample is placed in a flask containing 250 mL of o-xylene (solvent), and the resin composition is stirred for 30 minutes at 135 ° C. using a hot plate and a reflux device while performing nitrogen purging. After complete dissolution, it was cooled at 25 ° C. for 1 hour. The resulting solution was filtered using filter paper. 100 mL of the filtered filtrate was collected, transferred to an aluminum cup or the like, evaporated to dryness at 140 ° C. while purging with nitrogen, and allowed to stand at room temperature for 30 minutes to obtain a xylene-soluble component.
The ultimate viscosity was measured in tetrahydronaphthalene at 135 ° C. using an automatic capillary viscosity measuring device (SS-780-H1, manufactured by Shibayama Kagaku Kikai Seisakusho).

<Mw / Mn of xylene insoluble in polypropylene>
After filtration for obtaining the xylene-soluble component in the above measurement of XSIV, acetone was added to the residue (mixture of xylene-insoluble component and solvent) remaining on the filter paper and filtration was performed. Then, the components remaining on the filter paper without being filtered were evaporated to dryness in a vacuum drying oven set at 80 ° C. to obtain xylene insoluble matter (XI).
Using the above XI as a sample, the number average molecular weight (Mn) and the weight average molecular weight (Mw) are measured as follows, and the mass average molecular weight (Mw) is divided by the number average molecular weight (Mn) to obtain the molecular weight distribution (Mn). Mw / Mn) was calculated.
PL GPC220 manufactured by Polymer Laboratories is used as an apparatus, 1,2,4-trichlorobenzene containing an antioxidant is used as a mobile phase, and UT-G (1) and UT-807 (1) manufactured by Showa Denko KK as columns. One) and UT-806M (two) were connected in series, and a differential refractometer was used as a detector. The same solvent as the mobile phase was used as the solvent for the xylene-insoluble sample solution, and the sample was dissolved at a sample concentration of 1 mg / mL for 2 hours while shaking at a temperature of 150 ° C. to prepare a measurement sample. 500 μL of the sample solution thus obtained was injected into the column, and measurements were taken at a flow rate of 1.0 mL / min, a temperature of 145 ° C., and a data acquisition interval of 1 second. A polystyrene standard sample having a molecular weight of 580 to 7.45 million (shodex STANDARD, manufactured by Showa Denko KK) was used for column calibration, and the column was calibrated by a cubic approximation. The coefficients of Mark-Houwink are K = 1.21 × 10 ^-4 and α = 0.707 for polystyrene standard samples, and K = 1.37 × 10 ^-4 and α = 0 for propylene-based polymers. 75 was used.

〔material〕
Polypropylene (A-1): Polypropylene produced in Production Example 1 described later.
Polypropylene (A-2): Polypropylene produced in Production Example 2 described later.
Polypropylene (A-3): Polypropylene produced in Production Example 3 described later.
Polypropylene (A-4): Polypropylene produced in Production Example 4 described later.
Polypropylene (A-5): Polypropylene produced in Production Example 5 described later.
Polypropylene (A-6): Polypropylene produced in Production Example 6 described later.
Polypropylene (A-7): Polypropylene produced in Production Example 7 described later.
Polypropylene (A-8): Polypropylene produced in Production Example 8 described later.
Polypropylene (A-9): Polypropylene produced in Production Example 9 described later.
Note that polypropylene (A-2), (A-5), (A-6), (A-7), (A-8), and (A-9) are comparative products.

Elastomer (B-1): Ethylene-1-octene copolymer, Dow Inc. "Engage® 8100", MFR: 2 g / 10 min, Density: 0.872 g / cm ³ .
Elastomer (B-2): Ethylene-1-octene copolymer, "SOLUMER 861L" manufactured by SK Global Chemical, MFR: 2 g / 10 minutes, density: 0.860 g / cm ³ .
Elastomer (B-3): Ethylene-1-octene copolymer, "SOLUMER 851L" manufactured by SK Global Chemical, MFR: 2 g / 10 minutes, density: 0.850 g / cm ³ .
Elastomer (B-4): Ethylene-1-butene copolymer, "A-1050S" manufactured by Mitsui Chemicals, MFR: 2 g / 10 minutes, density: 0.862 g / cm ³ .
Talc: Neo Talc UNI05 manufactured by Neolite Kosan.
MgSt: Magnesium stearate, manufactured by NOF CORPORATION.
Antioxidant: "B225" manufactured by BASF.
Neutralizer: Calcium stearate, manufactured by Tannan Chemical Industry Co., Ltd.
Lightproofing agent: "ADEKA STAB LA502XP" manufactured by ADEKA.

<Manufacturing Example 1: Manufacture of polypropylene (A-1)>
A solid catalyst in which Ti and diisobutyl phthalate as an internal donor were supported on MgCl _{2 was prepared by the method described in Example 5 of European Patent No. 728769.} Next, using the solid catalyst, triethylaluminium (TEAL) as the organoaluminum compound, and dicyclopentyldimethoxysilane (DCPMS) as the external electron donor compound, the mass ratio of TEAL to the solid catalyst was 20, and the mass ratio of TEAL to DCPMS was 20. The catalyst was obtained by contacting at 12 ° C. for 24 minutes in an amount of 10.
The obtained catalyst was prepolymerized by holding it in a suspended state in liquid propylene at 20 ° C. for 5 minutes to obtain a prepolymer.
The obtained prepolymer was introduced into a first-stage polymerization reactor of a polymerization apparatus equipped with a two-stage polymerization reactor in series, and propylene was further supplied for polymerization to produce homopolypropylene. The homopropylene, ethylene, and propylene were supplied to the second-stage polymerization reactor to carry out polymerization to produce an ethylene-propylene copolymer. As a result, polypropylene (A-1) composed of a homopolypropylene component and an ethylene-propylene copolymer component was obtained.
During the polymerization, the temperature and pressure were adjusted, and hydrogen was used as a molecular weight modifier.
The ratio of the polymerization temperature to the reactants was as follows: in the first-stage polymerization reactor, the polymerization temperature and hydrogen concentration were 70 ° C. and 3.95 mol%, respectively, and in the second-stage polymerization reactor, the polymerization temperature and hydrogen concentration were C2 /. The molar ratios of (C2 + C3) were 80 ° C., 1.52 mol% and 0.21, respectively. C2 and C3 represent ethylene and propylene, respectively. Further, the residence time distributions of the first and second stages were adjusted so that the content (BIPO) of the ethylene-propylene copolymer component was 15.5% by mass.
The obtained polypropylene (A-1) had an MFR of 108 g / 10 minutes, BIPO of 15.5% by mass, PC of 72.5% by mass, XSIV of 2.6 dL / g, and XI of Mw / Mn of 5.3. Met.

<Manufacturing Example 2: Manufacture of polypropylene (A-2)>
Manufactured except that the hydrogen concentration of the first-stage polymerization reactor was changed to 2.93 mol%, and the hydrogen concentration of the second-stage polymerization reactor and C2 / (C2 + C3) were changed to 2.45 mol% and 0.45 mol ratio. In the same manner as in Example 1, a polypropylene (A-2) composed of a homopolypropylene component and an ethylene-propylene copolymer component was obtained.
The MFR of polypropylene (A-2) was 106 g / 10 minutes, the BIPO was 15.5% by mass, the PC was 53.5% by mass, the XSIV was 2.0 dL / g, and the Mw / Mn of XI was 5.7. ..

<Manufacturing Example 3: Manufacture of polypropylene (A-3)>
The hydrogen concentration of the first-stage polymerization reactor was changed to 3.23 mol%, the hydrogen concentration of the second-stage polymerization reactor was changed to 1.75%, and the BIPO was 14.9% by mass. Polypropylene (A-3) composed of a homopolypropylene component and an ethylene-propylene copolymer component was obtained in the same manner as in Production Example 1 except that the residence time distribution of the steps was adjusted.
The MFR of polypropylene (A-3) was 95 g / 10 minutes, the BIPO was 14.9% by mass, the PC was 72.5% by mass, the XSIV was 2.4 dL / g, and the Mw / Mn of XI was 5.5. ..

<Manufacturing Example 4: Manufacture of polypropylene (A-4)>
The same as in Production Example 3 except that the residence time distributions of the first and second stages were adjusted so that the hydrogen concentration of the first stage polymerization reactor was 3.07 mol% and the BIPO was 14.0% by mass. A polypropylene (A-4) composed of a homopolypropylene component and an ethylene-propylene copolymer component was obtained.
The MFR of polypropylene (A-4) was 95 g / 10 min, the BIPO was 14.0 mass%, the PC was 72.5 mass%, the XSIV was 2.4 dL / g, and the Mw / Mn of XI was 5.6. ..

<Manufacturing Example 5: Manufacture of polypropylene (A-5)>
The homopolypropylene component and ethylene-are the same as in Production Example 1 except that the hydrogen concentration of the first-stage polymerization reactor was changed to 3.19 mol% and the hydrogen concentration of the second-stage polymerization reactor was changed to 2.21%. Polypropylene (A-5) composed of a propylene copolymer component was obtained.
The MFR of polypropylene (A-5) was 108 g / 10 minutes, BIPO was 15.5% by mass, PC was 72.5% by mass, XSIV was 2.1 dL / g, and Mw / Mn of XI was 5.5. ..

<Manufacturing Example 6: Manufacture of polypropylene (A-6)>
Polypropylene composed of a homopolypropylene component and an ethylene-propylene copolymer component was obtained in the same manner as in Production Example 1 except that the hydrogen concentration of the first-stage polymerization reactor was changed to 2.15 mol%. To the obtained powdered polypropylene, 0.2% by mass of BASF B225 as an antioxidant and 0.05% by mass of Tannan Chemical Industry's calcium stearate as a neutralizing agent were added, and MFR was further added. Evonik Japan's 2,5-dimethyl-2,5-di (t-butylperoxy) hexane was blended as an adjusting agent, stirred and mixed with a Henschel mixer for 1 minute, and then uniaxially extruded with a screw diameter of 50 mm. Using a machine (manufactured by Nakatani Machinery Co., Ltd., model number NVC-50), the mixture was melt-kneaded at a cylinder temperature of 200 ° C. and extruded into strands. The extruded strands were cooled in water and then cut with a pelletizer to give pelletized polypropylene (A-6). The amount of the MFR adjuster was adjusted so that the MFR of the pellet was 108 g / 10 minutes.
The MFR of polypropylene (A-6) was 108 g / 10 minutes, BIPO was 15.5% by mass, PC was 72.5% by mass, XSIV was 2.3 dL / g, and Mw / Mn of XI was 3.5. ..

<Manufacturing Example 7: Manufacture of polypropylene (A-7)>
The hydrogen concentration of the first-stage polymerization reactor was changed to 2.30 mol%, the hydrogen concentration of the second-stage polymerization reactor was changed to 2.96 mol%, and the BIPO was 15.2% by mass. Polypropylene (A-7) composed of a homopolypropylene component and an ethylene-propylene copolymer component was obtained in the same manner as in Production Example 1 except that the residence time distribution in the second stage was adjusted.
The MFR of polypropylene (A-7) was 94 g / 10 minutes, the BIPO was 15.2% by mass, the PC was 72.5% by mass, the XSIV was 1.8 dL / g, and the Mw / Mn of XI was 5.9. ..

<Manufacturing Example 8: Manufacture of polypropylene (A-8)>
Manufactured except that the hydrogen concentration of the first-stage polymerization reactor was changed to 2.20 mol%, and the hydrogen concentration of the second-stage polymerization reactor and C2 / (C2 + C3) were changed to 3.31 mol%, which is a 0.20 mol ratio. In the same manner as in Example 3, a polypropylene (A-8) composed of a homopolypropylene component and an ethylene-propylene copolymer component was obtained.
The MFR of polypropylene (A-8) was 97 g / 10 min, the BIPO was 14.9 mass%, the PC was 72.8 mass%, the XSIV was 1.7 dL / g, and the Mw / Mn of XI was 6.0. ..

<Manufacturing Example 9: Manufacture of polypropylene (A-9)>
A solid catalyst was prepared based on the examples of Special Table 2011-500907. Specifically, a solid catalyst was prepared as follows.
_{250 mL of TiCl 4} was introduced at 0 ° C. into a 500 mL four-necked round bottom flask purged with nitrogen. While stirring, according to the method described in Example 2 10.0g of the fine spherical _{MgCl 2 · 1.8C 2 H 5 OH} ( US Patent 4,399,054, however operating at 3000rpm instead of 10000rpm production And 9.1 mmol of diethyl-2,3- (diisopropyl) succinate were added. The temperature was raised to 100 ° C. and held for 120 minutes. The stirring was then stopped, the solid product was allowed to settle and the supernatant was sucked out. The following operation was then repeated twice: 250 mL of fresh TiCl ₄ was added, the mixture was reacted at 120 ° C. for 60 minutes and the supernatant was sucked out. The solid was washed 6 times with anhydrous hexane (6 x 100 mL) at 60 ° C. to give a solid catalyst.
The solid catalyst and triethylaluminium (TEAL) and dicyclopentyldimethoxysilane (DCPMS) are prepared at room temperature in such an amount that the mass ratio of TEAL to the solid catalyst is 18 and the mass ratio of TEAL / DCPMS is 10. Contacted for minutes. The obtained catalyst system was prepolymerized by holding it in a suspended state in liquid propylene at 20 ° C. for 5 minutes to obtain a prepolymerized catalyst.
Manufactured using the obtained prepolymerization catalyst except that the hydrogen concentration of the first-stage polymerization reactor was changed to 1.78 mol% and the C2 / (C2 + C3) of the second-stage polymerization reactor was changed to 0.22 mol ratio. In the same manner as in Example 1, a polypropylene (A-9) composed of a homopolypropylene component and an ethylene-propylene copolymer component was obtained.
The MFR of polypropylene (A-9) was 108 g / 10 minutes, BIPO was 15.5% by mass, PC was 72.5% by mass, XSIV was 2.6 dL / g, and Mw / Mn of XI was 9.0. ..

<Example 1>
83 parts by mass of polypropylene (A-1) obtained in Production Example 1, 7 parts by mass of elastomer (B-1), 10 parts by mass of talc (component (C)), MgSt (component (D)) 0.2 parts by mass of the above, 0.2 parts by mass of the antioxidant, 0.05 parts by mass of the neutralizing agent, and 0.2 parts by mass of the light resistant agent were mixed and stirred with a Henschel mixer for 1 minute. After mixing, melt-knead using a twin-screw extruder (TEX30α manufactured by Japan Steel Works, Ltd.) with a screw diameter of 30 mm under the conditions of screw rotation speed of 500 rpm, cylinder temperature of 200 ° C., and discharge rate of 30 kg / hr, and extruded into strands. did. The extruded strands were cooled in water and then cut with a pelletizer to obtain pellets of a polypropylene resin composition having the composition shown in Table 1.

<Examples 2 to 7, Comparative Examples 1 to 7>
A polypropylene resin composition was obtained in the same manner as in Example 1 except that the type and amount of the materials to be mixed were changed so as to have the compositions shown in Table 1 or Table 2.

For the polypropylene-based resin compositions obtained in each example, the MFR and density were measured in the same manner as described above. In addition, the following evaluations were made. The results are shown in Tables 1-2.

(Flexural modulus)
The polypropylene resin composition is molded using an injection compression molding machine (ROBOSHOT S-2000i100B manufactured by FANUC) at a molding temperature of 200 ° C. according to JIS K6921-2 Table 1, and processed into a width of 10 mm, a length of 80 mm, and a thickness of 4 mm. Then, a test piece for measurement was obtained. For this measurement test piece, according to JIS K7171: 2008, using a fully automatic testing machine (AG-X10KN) manufactured by Shimadzu Corporation, the conditions are a temperature of 23 ° C., a relative humidity of 50%, a span interval of 64 mm, and a bending speed of 2.0 mm / min. The flexural modulus (MPa) was measured with.
The higher the flexural modulus, the better the rigidity. The flexural modulus is preferably 1900 MPa or more.

(Bending strength)
At the same time as the bending elastic modulus measurement, the bending strength (MPa) was measured according to JIS K7171: 2008.
The higher the bending strength value, the better the breakage resistance when a load is applied to the molded product. The bending strength is preferably 37 MPa or more.

(Charpy impact strength)
The polypropylene resin composition is molded using an injection compression molding machine (ROBOSHOT S-2000i100B manufactured by FANUC) at a molding temperature of 200 ° C. according to JIS K6921-2 Table 1, and processed into a width of 10 mm, a length of 80 mm, and a thickness of 4 mm. Then, a notch (shape A) of 2 mm was made in the width direction to obtain a test piece for measurement. ^{For this measurement test piece, the Charpy impact strength (kJ / m 2} ) was measured under the condition of a temperature of 23 ° C. using a digital impact tester (DG-UB2) manufactured by Toyo Seiki Seisakusho Co., Ltd. in accordance with JIS K7111-1: 2012. did.
The higher the Charpy impact strength value, the better the impact resistance. The Charpy impact strength is ^{preferably 6 kJ / m 2} or more.

In Tables 1 and 2, the contents of polypropylene (component (A)), component (B) and talc (component (C)) are ratios (mass%) to their total mass (100% by mass). The content of the components other than these is the ratio (parts by mass) of polypropylene, the component (B) and talc to a total of 100 parts by mass.

The polypropylene-based resin compositions of Examples 1 to 7 had a sufficiently large MFR and high fluidity. In addition, the molded product had an excellent balance between rigidity and impact resistance.
Since the molded product of the polypropylene resin composition of Comparative Example 1 has a PC of 69% by mass or less and an XSIV of less than 2.3 dL / g, it has impact resistance (Charpy impact strength) and breakage resistance (bending strength). Was inferior to. The molded articles of the polypropylene-based resin compositions of Comparative Examples 2 and 4 to 5 were inferior in impact resistance (Charpy impact strength) because the XSIV was less than 2.3 dL / g. The molded product of the polypropylene-based resin composition of Comparative Example 3 was inferior in rigidity (flexural modulus) and breakage resistance (bending strength) because Mw / Mn of XI was less than 4.0. The molded product of the polypropylene-based resin composition of Comparative Example 6 was inferior in rigidity (flexural modulus) and breakage resistance (bending strength) because the talc content was less than 7% by mass. The molded product of the polypropylene-based resin composition of Comparative Example 7 was inferior in impact resistance (Charpy impact strength) and breakage resistance (bending strength) because Mw / Mn of XI was more than 8.0.

Claims (4)

Component (A): It is composed of a homopolypropylene component and an ethylene-propylene copolymer component, has a melt mass flow rate of 80 to 110 g / 10 minutes at 230 ° C. and 21.18 N, and has an extreme viscosity of a xylene-soluble component. It is 2.3 to 2.9 dL / g, the molecular weight distribution (Mw / Mn) of the xylene insoluble matter is 4.0 to 8.0, and the content of the ethylene-propylene copolymer component is the total content of the polypropylene. With polypropylene which is 13 to 20% by mass with respect to the mass and the propylene content of the ethylene-propylene copolymer component is more than 69% by mass and 79% by mass or less with respect to the total mass of the ethylene-propylene copolymer component. ,
(B) Component: An ethylene-α-olefin copolymer having 4 to 8 carbon atoms of α-olefin, having a melt mass flow rate of 1 to 4 g / 10 minutes at 230 ° C. and 21.18 N, and having a density of 1 to 4 g / 10 minutes. With an elastomer of 0.847 to 0.873 g / cm ^3,
(C) Ingredients: talc and
Including
When the total mass of the component (A), the component (B) and the component (C) is 100% by mass, the content of the component (A) is 78 to 89% by mass, and the component (B) The content of the component (C) is 4 to 9% by mass, and the content of the component (C) is 7 to 13% by mass.
A polypropylene-based resin composition having a melt mass flow rate of 69 to 100 g / 10 minutes at 230 ° C. and 21.18 N in the entire composition. Ingredient (D): Further containing magnesium stearate,
The first aspect of the present invention, wherein the content of the component (D) is 0.05 to 1 part by mass with respect to a total of 100 parts by mass of the component (A), the component (B), and the component (C). Polypropylene resin composition. An injection compression molded product made of the polypropylene-based resin composition according to claim 1 or 2. The injection compression molded article according to claim 3, which is for an automobile interior.