JP2021024955A - Filler-containing polypropylene resin composition and automobile exterior component - Google Patents

Abstract

To provide a filler-containing polypropylene resin composition that has excellent physical properties of rigidity, impact resistance, and heat resistance and expresses an excellent jet-black color, and an automobile exterior component.SOLUTION: A filler-containing polypropylene resin composition contains a propylene polymer (A) 60-75 pts.mass, an ethylene-α-olefin copolymer (B) 0-5 pts.mass, an inorganic filler (C) 25-35 pts.mass, a hindered phenolic antioxidant (D-1) with a molecular weight of 1000 or more of 0.01-1.0 pts.mass, a hindered phenolic antioxidant (D-2) with a molecular weight of less than 1000 of 0.01-1.0 pts.mass, a benzoate photostabilizer (E-1) with a molecular weight of less than 1000 of 0.01-0.5 pts.mass, a hindered amine photostabilizer (E-2) with a molecular weight of less than 1000 of 0.01-0.5 pts.mass, carbon black (F-1) 0.4-1.0 pts.mass, titanium oxide (F-2) 0.5 pts.mass or less, a green pigment or blue pigment (F-3) 0.05-0.5 pts.mass, and a fatty acid metal salt (G) 0.01-1.0 pts.mass. There is also provided an automobile exterior component obtained by injection-molding the same.SELECTED DRAWING: None

Description

The present invention relates to a filler-containing polypropylene-based resin composition and automobile exterior parts, which are excellent in physical properties of rigidity, impact resistance, and heat resistance, and exhibit good jet-blackness.

The molded product obtained by injection molding a polypropylene-based resin composition has excellent mechanical properties and moldability, and also has relatively advantageous cost performance as compared with other materials. Therefore, automobile parts and home appliance parts It is being used in various fields such as. In recent years, in order to improve various physical properties, a composition containing an ethylene / propylene block copolymer, a rubber component such as an ethylene / α-olefin copolymer, an inorganic filler, and various other additives. Has been proposed.

For example, Patent Document 1 describes crystalline ethylene / propylene block copolymers, elastomers, inorganic fillers, organic phosphorus-based antioxidants, and hindered phenol-based oxidations that do not contain nitrogen atoms and have a molecular weight of 500 or more. A polypropylene-based resin composition containing an inhibitor, a hindered phenol-based antioxidant containing a nitrogen atom, and a hindered amine-based photostabilizer having no NH bond is disclosed. It is described that this polypropylene resin composition is excellent in weather resistance, paintability after plasma treatment, and yellowing resistance of the painted coating film.

Patent Document 2 describes propylene-ethylene block copolymers, olefin elastomers, inorganic fillers, black pigments, white pigments, hindered phenolic antioxidants, ultraviolet absorbers, and hindered amine-based photostabilizers. A polypropylene resin composition containing an agent is disclosed. It is described that this polypropylene resin composition is excellent in weather resistance, paintability after plasma treatment, and yellowing resistance of the painted coating film.

Patent Document 3 describes a hindered amine-based light-resistant stabilizer formed of polypropylene, talc, an elastomer, and a piperidine derivative having a molecular weight of 600 to 950, and a hindered amine-based light-resistant stabilizer having an NH bond and having a molecular weight of 1000 or more. and stabilizers, and N-CH ₃ have a binding and molecular weight of 600 or more hindered amine light stabilizer, a polypropylene resin composition comprising a triaryl phosphite heat stabilizer is disclosed. It is also described that inorganic pigments such as metal oxides, sulfides and sulfates, and organic pigments such as phthalocyanine, quinacridone and benzidine can be blended. It is described that this polypropylene-based resin composition can continuously injection-mold a molded product having excellent light resistance and little change in gloss for a long time.

Patent Document 4 describes a propylene / ethylene block copolymer composed of a crystalline polypropylene component and a propylene ethylene random copolymer component, a propylene polymer, an ethylene / α-olefin copolymer rubber, and a molecular weight of 700 or more. A polypropylene block copolymer composition containing a hindered amine-based light stabilizer is disclosed. It is also described that coloring substances such as quinacridone, perylene, phthalocyanine, titanium oxide, and carbon black can be blended. It is described that this polypropylene block copolymer composition is excellent in ductility, dimensional stability, surface quality, weather resistance, and prevention of fogging on the inner surface of glass.

Patent Document 5 describes a crystalline propylene block copolymer, a crystalline propylene homopolymer, an elastomeric polymer composition having a specific composition, an inorganic filler, a hindered amine-based weather-resistant stabilizer, and hindered. A resin composition for an automobile exterior containing a phenolic ultraviolet absorber is disclosed. This resin composition for automobile exterior has an excellent balance of fluidity and physical properties (flexural modulus, impact resistance, hardness, embrittlement temperature, etc.), has a small heat shrinkage rate, and has few flow marks and weld marks. It is stated that the molded product can be easily molded.

Japanese Unexamined Patent Publication No. 6-107897 Japanese Unexamined Patent Publication No. 9-9592 JP-A-2002-012720 Japanese Unexamined Patent Publication No. 2008-101091 Japanese Unexamined Patent Publication No. 2005-14601

The present inventors have focused on the necessity of a jet-black appearance, which is excellent in each physical property and has not been studied in the prior art described above. That is, an object of the present invention is to provide a filler-containing polypropylene-based resin composition and automobile exterior parts that are excellent in physical properties of rigidity, impact resistance, and heat resistance and exhibit good jet-blackness.

As a result of diligent studies to achieve the above object, the present inventors have found that a filler-containing polypropylene resin composition having a specific composition is very effective, and have completed the present invention. That is, the present invention is specified by the following matters.

[1] Ethylene-propylene copolymer part (A2) 0 to 30% by mass having a propylene homopolymer part (A1) of 70 to 100% by mass and an ultimate viscosity [η] of 2.0 to 8.0 dl / g. 60 to 75 parts by mass of the propylene-based polymer (A) composed of% (the total of the component (A1) and the component (A2) is 100% by mass).
Ethylene / α-olefin copolymer (B) (α-olefin has 3 to 10 carbon atoms) 0 to 5 parts by mass,
Inorganic filler (C) 25 to 35 parts by mass,
As the antioxidant (D), a hindered phenolic antioxidant (D-1) having a molecular weight of 1000 or more is 0.01 to 1.0 parts by mass, and a hindered phenolic antioxidant (D-2) having a molecular weight of less than 1000 is used. ) 0.01 to 1.0 parts by mass,
As the weather resistance stabilizer (E), a benzoate-based light stabilizer (E-1) having a molecular weight of less than 1000 (0.01 to 0.5 parts by mass) and a hindered amine-based light stabilizer (E-2) having a molecular weight of less than 1000 (E-2) 0. 01-0.5 parts by mass,
As the pigment (F), carbon black (F-1) 0.4 to 1.0 parts by mass, titanium oxide (F-2) 0.5 parts by mass or less, and a green pigment or a blue pigment (F-3). ) 0.05-0.5 parts by mass and
Fatty acid metal salt (G) 0.01 to 1.0 parts by mass [However, the total amount of the component (A), the component (B) and the component (C) is 100 parts by mass. ]
Filler-containing polypropylene-based resin composition containing.

[2] The filler-containing polypropylene-based resin composition according to [1], wherein the propylene-based polymer (A) is a propylene / ethylene block copolymer.

[3] An automobile exterior component obtained by injection molding the filler-containing polypropylene-based resin composition according to [1] or [2].

According to the present invention, it is possible to provide a filler-containing polypropylene-based resin composition having excellent rigidity, impact resistance, and heat resistance, as well as good jet-blackness, and automobile exterior parts.

Since the filler-containing polypropylene-based resin composition of the present invention has a specific composition, it is excellent in physical properties such as rigidity, impact resistance, and heat resistance. Further, a specific amount of the inorganic filler (C) is combined with a specific amount of three kinds of pigments (F-1), (F-2) and (F-3) [particularly the pigment (F-3)]. As a result, a high-quality and good jet-blackness is exhibited.

<Propylene polymer (A)>
The propylene-based polymer (A) used in the present invention is a propylene homopolymer portion (A1) of 70 to 100% by mass, and both ethylene and propylene having an ultimate viscosity [η] of 2.0 to 8.0 dl / g. It is a propylene-based polymer composed of 0 to 30% by mass of the polymer portion (A2) (the total of the component (A1) and the component (A2) is 100% by mass).

The propylene-based polymer (A) may be a propylene homopolymer or a propylene / ethylene block copolymer. In the case of a propylene homopolymer, the amount of the propylene homopolymer portion (A1) is 100% by mass, and in the case of a propylene / ethylene block copolymer, the amount of the propylene homopolymer portion (A1) is 100% by mass. Is less than. In particular, the propylene-based polymer (A) is preferably a propylene / ethylene block copolymer.

In the propylene-based polymer (A), the amount of the propylene homopolymer portion (A1) is 70 to 100% by mass, preferably 75 to 95% by mass, and more preferably 80 to 90% by mass. The amount of the ethylene / propylene copolymer portion (A2) is 0 to 30% by mass, preferably 5 to 25% by mass, and more preferably 10 to 20% by mass.

The amounts of the propylene homopolymer part (A1) and the ethylene / propylene copolymer part (A2) in the propylene-based polymer (A) can be decaned with the decan-insoluble part as described in the column of Examples described later. It can be determined by the amount of melt. Specifically, the decane-insoluble portion is a component that is generally insoluble in an n-decane solvent at room temperature (23 ° C.), and is usually a propylene homopolymer portion (A1) in the propylene-based polymer (A). Equivalent. On the other hand, the decan-soluble portion is usually equivalent to a portion other than the propylene homopolymer portion (that is, the ethylene / propylene copolymer portion (A2)).

The intrinsic viscosity [η] of the ethylene / propylene copolymer portion (A2) is 2.0 to 8.0 dl / g.

The melt flow rate (230 ° C., 2.16 kg load) of the propylene-based polymer (A) is preferably 5 to 300 g / 10 minutes, more preferably 10 to 250 g / 10 minutes.

The propylene-based polymer (A) can be produced by a known method. The propylene / ethylene block copolymer, which is a preferred embodiment of the propylene-based polymer (A), uses, for example, an olefin polymerization catalyst containing a solid titanium catalyst component (I) and an organic metal compound catalyst component (II). A propylene-based block copolymer can be obtained by polymerizing propylene and further copolymerizing propylene and ethylene. The solid titanium catalyst component (I) contains, for example, titanium, magnesium, halogens and optionally electron donors. A known component can be used without limitation for the solid titanium catalyst component (I). The organometallic compound catalyst component (II) is a component containing a metal element selected from Group 1, Group 2, and Group 13 of the periodic table. For example, a compound containing a Group 13 metal (organometallic compound or the like), a complex alkylated product of a Group 1 metal and aluminum, an organometallic compound of a Group 2 metal, or the like can be used. Of these, organoaluminum compounds are preferable.

The propylene / ethylene block copolymer, which is a preferred embodiment of the propylene-based polymer (A), polymerizes propylene in the presence of the above-mentioned olefin polymerization catalyst, and then copolymerizes or prepolymerizes propylene and ethylene. It can be produced by a method such as polymerizing propylene in the presence of the obtained prepolymerized catalyst and then copolymerizing propylene and ethylene. The polymerization can be carried out by any of a batch type, a semi-continuous type and a continuous type.

<Ethylene / α-olefin copolymer (B)>
The ethylene / α-olefin copolymer (B) used in the present invention is a copolymer of ethylene and an α-olefin having 3 to 10 carbon atoms, and is usually a random copolymer.

Specific examples of the α-olefin having 3 to 8 carbon atoms constituting the ethylene / α-olefin copolymer (B) include propylene, 1-butene, 1-pentene, 1-hexene, and 3-methyl-1-. Butene, 4-methyl-1-pentene, 1-hexene and 1-octene can be mentioned. One type of α-olefin may be used alone, or two or more types may be used in combination. Of these, 1-butene, 1-hexene and 1-octene are preferable. As the ethylene / α-olefin copolymer (C), an ethylene-octene copolymer and an ethylene-butene copolymer are particularly preferable.

The ethylene content of the ethylene / α-olefin copolymer (B) is preferably 70 to 95 mol%, more preferably 75 to 95 mol%.

The melt flow rate (230 ° C., 2.16 kg load) of the ethylene / α-olefin copolymer (B) is preferably 0.1 to 30 g / 10 minutes, more preferably 1 to 10 g / 10 minutes.

The density of the ethylene / α-olefin copolymer (B) is preferably 850 to 900 g / cm ³ , and more preferably 850 to 890 g / cm ³ .

<Inorganic filler (C)>
The type of the inorganic filler (C) used in the present invention is not particularly limited, and various known inorganic fillers can be used. Specific examples include talc, mica, calcium carbonate, barium sulfate, glass fiber, gypsum, magnesium carbonate, magnesium oxide, titanium oxide, and iron oxide. Further, metal powders such as zinc, copper, iron and aluminum or metal fibers can also be mentioned. These may be used individually by 1 type, and may be used in combination of 2 or more type. Of these, talc, mica, calcium carbonate, and glass fiber are preferable, and talc having a good balance between rigidity and impact is particularly preferable.

The average particle size of the inorganic filler (C) such as talc is usually 1 to 15 μm, preferably 1 to 6 μm. When the average particle size is not more than the upper limit of these ranges, it tends to be possible to maintain a good balance of physical properties of rigidity and impact resistance. This average particle size is a value measured by a laser diffraction method.

<Antioxidant (D)>
The antioxidant (D) used in the present invention is a hindered phenolic antioxidant (D-1) having a molecular weight of 1000 or more and a hindered phenolic antioxidant (D-2) having a molecular weight of less than 1000.

The type of the hindered phenolic antioxidant (D-1) having a molecular weight of 1000 or more is not particularly limited, and various known hindered phenolic antioxidants can be used. Such a hindered phenolic antioxidant (D-1) is available as a commercial product. Preferred commercial products are, for example, pentaerythritol-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate (manufactured by BASF Japan Ltd., Irganox® 1010, molecular weight = 1177.7). ).

The type of the hindered phenolic antioxidant (D-2) having a molecular weight of less than 1000 is not particularly limited, and various known hindered phenolic antioxidants can be used. Such a hindered phenolic antioxidant (D-2) is available as a commercial product. Preferred commercially available products are, for example, octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate (BASF Japan Ltd., Irganox® 1076, molecular weight = 530.9), Tris. -(3,5-di-t-butyl-4-hydroxybenzyl) -isocyanurate (manufactured by BASF Japan Ltd., Irganox® 3114, molecular weight = 784.0).

<Weather-resistant stabilizer (E)>
The weather-resistant stabilizer (E) used in the present invention is a benzoate-based light stabilizer (E-1) having a molecular weight of less than 1000 and a hindered amine-based light stabilizer (E-2) having a molecular weight of less than 1000. The weather-resistant stabilizer (E) may be commercially available as an ultraviolet absorber.

The type of the benzoate-based light stabilizer (E-1) having a molecular weight of less than 1000 is not particularly limited, and various known benzoate-based light stabilizers can be used. Such a benzoate-based light stabilizer (E-1) is available as a commercially available product. Preferred commercial products are, for example, 2,4-di-t-butylphenyl-3,5-di-t-butyl-4-hydroxybenzoate (manufactured by BASF Japan Ltd., Tinuvin® 120, molecular weight = 438. 7).

The type of the hindered amine-based light stabilizer (E-2) having a molecular weight of less than 1000 is not particularly limited, and various known hindered amine-based light stabilizers can be used. Such a hindered amine-based light stabilizer (E-2) is available as a commercially available product. Preferred commercial products are, for example, tetrakis (1,2,2,6,6-pentamethyl-4-piperidyl) 1,2,3,4-butanetetracarboxylate (manufactured by ADEKA Corporation, trade name LA-52, molecular weight). = 847.2), tetrakis (1,2,2,6,6-pentamethyl-4-piperidyl) butane-1,2,3,4-butanetetracarboxylate (manufactured by ADEKA Corporation, trade name LA-57, Molecular weight = 792) 1,2,2,6,6-pentamethyl-4-piperidyl / tridecyl-1,2,3,4-butanetetracarboxylate (manufactured by ADEKA Corporation, trade name LA-62, molecular weight = approx. 900) 2,2,6,6-tetramethyl-4-piperidyl / tridecyl-1,2,3,4-butanecarboxylate (manufactured by ADEKA Corporation, trade name LA-67, molecular weight = about 900), bis (2,2,6,6-tetramethyl-4-piperidyl) Sepacate (manufactured by BASF Japan Corporation, Tinuvin (registered trademark) 770, molecular weight = 480.7).

<Weather-resistant stabilizer (E)>
The pigment (F) used in the present invention is carbon black (F-1), titanium oxide (F-2), and a green pigment or a blue pigment (F-3).

The type of carbon black (F-1) is not particularly limited, and various known carbon blacks can be used. Carbon black (F-1) is available as a commercial product. The average particle size is also not limited, but the average primary particle size is preferably 10 to 40 nm.

The type and average particle size of titanium oxide (F-2) are not particularly limited, and various known titanium oxides can be used. Titanium oxide (F-2) is available as a commercial product.

The type of the green pigment or the blue pigment (F-3) is not particularly limited, and various known green pigments or various blue pigments can be used. Preferred specific examples include phthalocyanine pigments. The green pigment or the blue pigment (F-3) is available as a commercial product. Preferred commercial products are, for example, blue pigments (manufactured by Clariant, trade name PV Fast Blue A4R) and green pigments (manufactured by Heubach, trade name Vynamon Green 600734).

<Fatty acid metal salt (G)>
The type of fatty acid metal salt (G) used in the present invention is not particularly limited, and various known fatty acid metal salts can be used. Specific examples include magnesium stearate, calcium stearate, and zinc stearate. The fatty acid metal salt (G) is available as a commercial product.

If necessary, the polypropylene-based resin composition may contain other additives such as a nucleating agent, a heat-resistant stabilizer, an antistatic agent, an antiaging agent, a softener, a dispersant, and a lubricant, which do not impair the object of the present invention. It can be blended in a range. The mixing order of the additives is arbitrary, and they may be mixed at the same time, or a multi-step mixing method such as mixing a part of the components and then mixing the other components may be used.

<Filler-containing polypropylene resin composition>
The filler-containing polypropylene-based resin composition of the present invention is a composition containing each of the above-described components (A) to (G) and, if necessary, other optional components. The amount of each component described below is an amount when the total amount of the components (A) to (C) is 100 parts by mass.

The amount of the propylene-based polymer (A) is 60 to 75 parts by mass, preferably 65 to 75 parts by mass.

The amount of the ethylene / α-olefin copolymer (B) is 0 to 5 parts by mass, preferably 0 to 4 parts by mass.

The amount of the inorganic filler (C) is 25 to 35 parts by mass, preferably 30 to 35 parts by mass.

The amount of the hindered phenolic antioxidant (D-1) having a molecular weight of 1000 or more is 0.01 to 1.0 parts by mass, preferably 0.1 to 0.2 parts by mass. The amount of the hindered phenolic antioxidant (D-2) having a molecular weight of less than 1000 is 0.01 to 1.0 parts by mass, preferably 0.1 to 0.2 parts by mass by mass.

The amount of the benzoate-based light stabilizer (E-1) having a molecular weight of less than 1000 is 0.01 to 0.5 parts by mass, preferably 0.05 to 0.2 parts by mass. The amount of the hindered amine-based light stabilizer (E-2) having a molecular weight of less than 1000 is 0.01 to 0.5 parts by mass, preferably 0.05 to 0.2 parts by mass.

The amount of carbon black (F-1) is 0.4 to 1.0 parts by mass, preferably 0.5 to 0.9 parts by mass. The amount of titanium oxide (F-2) is 0.5 parts by mass or less, preferably 0.1 to 0.3 parts by mass. The amount of the green pigment or the blue pigment (F-3) is 0.05 to 0.5 parts by mass, preferably 0.1 to 0.4 parts by mass.

The amount of the fatty acid metal salt (G) is 0.01 to 1.0 parts by mass, preferably 0.1 to 0.5 parts by mass.

The filler-containing polypropylene-based resin composition of the present invention can be produced by blending the above-mentioned components (A) to (G) and, if necessary, other optional components. Each component may be sequentially blended in any order, or may be mixed at the same time. Further, a multi-step mixing method in which some components are mixed and then other components are mixed may be adopted. As a method of blending each component, for example, a method of mixing or melt-kneading each component simultaneously or sequentially using a mixing device such as a Banbury mixer, a single-screw extruder, a twin-screw extruder, or a high-speed twin-screw extruder is used. Can be mentioned.

The melt flow rate (230 ° C., 2.16 kg load) of the filler-containing polypropylene resin composition of the present invention is preferably 5 to 100 g / 10 minutes, more preferably 5 to 50 g / 10 minutes.

The molding method of the filler-containing polypropylene-based resin composition of the present invention is not particularly limited, and various known methods for molding the resin composition can be used. Injection molding is particularly preferable. The filler-containing polypropylene-based resin composition of the present invention can be suitably used in various fields such as automobile exterior parts, household goods, and home appliance parts. In particular, automobile exterior parts obtained by injection molding this resin composition are suitable. Specific examples of automobile exterior parts include bumpers, side moldings, back doors, fenders, and back panels.

Hereinafter, the present invention will be described in more detail based on Examples. However, the present invention is not limited thereto.

The physical properties of the examples and comparative examples were measured and evaluated by the following methods.

[Melt flow rate (MFR) (g / 10 minutes)]
The measurement was performed under the conditions of a test load of 2.16 kg and a test temperature of 230 ° C. in accordance with ISO 1133.

[Ultimate viscosity [η]]
About 20 mg of the sample was dissolved in 15 ml of decalin, and the specific viscosity η _sp was measured in an oil bath at 135 ° C. 5 ml of a decalin solvent was added to this decalin solution to dilute it, and then the specific viscosity η _sp was measured in the same manner. _{This dilution operation was repeated twice more, and the value of η sp} / C when the concentration (C) was extrapolated to 0 was determined as the ultimate viscosity [η].
[Η] = lim (η _sp / C) (C → 0)

[Decane-soluble component quantity (D _sol) and insoluble portion weight (D _insol) (wt%)]
Approximately 3 g of sample [component (A)] (measured to the unit of ^10-4 _{g. This mass was expressed as x 2} (g) in the following formula), n-decane 500 ml, in a glass measuring container. A small amount of a heat-resistant stabilizer soluble in water and n-decane was charged, and the sample was dissolved by raising the temperature to 150 ° C. in 2 hours while stirring with a stirrer in a nitrogen atmosphere, and then holding the sample at 150 ° C. for 2 hours. It was slowly cooled to 23 ° C. over 8 hours. The liquid containing the obtained precipitate was filtered under reduced pressure with a 25G-4 standard glass filter manufactured by Iwata Glass Co., Ltd. 100 ml of the filtrate was collected and dried under reduced pressure to obtain a part of the decan-soluble component, and the mass ^{was measured to the unit of 10-4} g (this mass is expressed as x ₁ (g) in the following formula. did). Using this measured value, to determine decane soluble part amount at room temperature (i.e. 23 ℃) (D _sol) and insoluble portion amount (D _insol) by the following equation.
D _sol (mass%) = 100 x (500 x x ₁ ) / (100 x x ₂ )
D _insol (% by mass) = 100-D _sol

[Bending elastic modulus (MPa)]
It was measured under the following conditions in accordance with ASTM D790.
Temperature: 23 ° C
Specimen: 127 mm (length) x 12.7 mm (width) x 6.35 mm (thickness)
Bending speed: 30 mm / min
Between spans: 100 cm

[Deflection temperature under load (° C)]
It was measured under the following conditions according to ASTM D648.
Specimen: 127 mm (length) x 12.7 mm (width) x 6.35 mm (thickness)
How to place the test piece: Edgewise bending stress: 0.45 MPa

[Izod impact strength (J / m)]
It was measured under the following conditions in accordance with ASTM D256.
Specimen: 63.5 mm (length) x 12.7 mm (width) x 3.2 mm (thickness) Notched Test temperature: -30 ° C

[Weather resistance test (SWOM)]
The color difference (ΔE) was measured under the following conditions to confirm the presence or absence of cracks.
Light source: Sunshine CarboArc BPT: 83 ° C
Precipitation conditions: 12/60 minutes Irradiation time: 2000hr
Specimen: 60 mm (length) x 40 mm (width) x 3 mm (thickness)
Color difference: Calculate the sample before the weather resistance test and ΔE after 2000 hours of the weather resistance test. Check the color difference using a color difference meter under the following conditions. Reflection method, SCI, light source: C / 2
Appearance: Check for cracks with a microscope

[Heat resistance test]
A heat resistance test was conducted under the following conditions.
Specimen (1): 63.5 mm (length) x 12.7 mm (width) x 3.2 mm (thickness) with notch Specimen (2): 60 mm (length) x 40 mm (width) x 3 mm (thickness)
Testing machine: Gear oven Test temperature: 120 ° C
Test time: 2000hr

(1) Impact strength retention rate (%) after heat resistance test
The Izod impact strength of the test piece (1) after the heat resistance test was measured by the method described above, and the impact strength retention rate (%) was calculated by dividing by the Izod impact strength before the heat resistance test and multiplying by 100. ..
(2) Appearance after heat resistance test The test piece (2) after the heat resistance test was checked for cracks using a microscope.

[Color tone]
The color tone was measured under the following conditions in accordance with JIS Z 8722, and the L value, a value, and b value were calculated according to JIS Z 8781.
Specimen: 90 mm (length) x 50 mm (width) x 2 mm (thickness)
Light source: D65
Field of view: 10 °
Specular light processing: SCI

When the L value, a value, and b value of the composition are within the following ranges, the jet blackness tends to be excellent, and this is set as the target value in this test.
L value: <27
a value: -1 to 0
b value: -1.5 to 0.5

In Examples and Comparative Examples, the propylene-based block copolymer obtained in Production Example 1 below was used as the component (A).

<Manufacturing example 1>
(1) Preparation of solid titanium catalyst component 95.2 g of anhydrous magnesium chloride, 442 ml of decan and 390.6 g of 2-ethylhexyl alcohol were heated at 130 ° C. for 2 hours to prepare a uniform solution, and phthalic anhydride 21 was added to this solution. .3 g was added, and the mixture was further stirred and mixed at 130 ° C. for 1 hour to dissolve phthalic anhydride.

After cooling this uniform solution to room temperature, 75 ml of the uniform solution was added dropwise over 200 ml of titanium tetrachloride kept at −20 ° C. for 1 hour. After the charging was completed, the temperature of this mixed solution was raised to 110 ° C. over 4 hours, 5.22 g of diisobutyl phthalate (DIBP) was added when the temperature reached 110 ° C., and the mixture was stirred and held at the same temperature for 2 hours. ..

After completion of the reaction for 2 hours, the solid part was collected by hot filtration, the solid part was resuspended in 275 mL of titanium tetrachloride, and then heated again at 110 ° C. for 2 hours. After completion of the reaction, the solid part was collected again by hot filtration and washed thoroughly with decane and hexane at 110 ° C. until no free titanium compound was detected in the solution.

The detection of this free titanium compound was confirmed by the following method. 10 mL of the supernatant of the solid catalyst component was collected with a syringe and charged into 100 mL of Schlenk with branches which had been replaced with nitrogen in advance. Next, the solvent hexane was dried in a nitrogen stream and vacuum dried for another 30 minutes. 40 mL of ion-exchanged water and 10 mL of (1 + 1) sulfuric acid were charged therein and stirred for 30 minutes. Transfer this aqueous solution through a filter paper to a 100 mL volumetric flask, then _{add 1 mL of concentrated H 3} PO _{4 solution as a masking agent for iron (II) ions and 5 mL of 3% H 2} O ₂ as a color-developing reagent for titanium, and then add ion-exchanged water. The volumetric flask made up to 100 mL was shaken, and after 20 minutes, the absorbance at 420 nm was observed using UV, and free titanium was washed and removed until this absorption was no longer observed.

The solid titanium catalyst component prepared as described above was stored as a decan slurry, and a part of the solid titanium catalyst component was dried for the purpose of examining the catalyst composition. The composition of the solid titanium catalyst component thus obtained was 2.3% by weight of titanium, 61% by weight of chlorine, 19% by weight of magnesium, and 12.5% by weight of DIBP.

(2) Production of prepolymerization catalyst 100 g of the solid titanium catalyst component, 39.3 mL of triethylaluminum, and 100 L of heptane are inserted into an autoclave with a stirrer having an internal volume of 200 L, and 600 g of propylene is inserted while maintaining an internal temperature of 15 to 20 ° C. , The reaction was carried out with stirring for 70 minutes.

(3) Main Polymerization In a circulating tubular polymerizer with a jacket having a content of 58 L, propylene was 43 kg / hour, hydrogen was 123 NL / hour, and the catalyst slurry produced in (2) above was used as a solid titanium catalyst component at 0.56 g / hour. For hours, 1.9 mL / hour of triethylaluminum and 3.7 mL / hour of dicyclopentyldimethoxysilane were continuously supplied, and polymerization was carried out in a full liquid state in which no gas phase was present. The temperature of the tubular polymerizer was 69 ° C. and the pressure was 3.5 MPa / G.

The obtained slurry was sent to a Vessel polymerizer with a stirrer having an content of 100 L, and further polymerization was carried out. Propylene was supplied to the polymerizer at 45 kg / hour and hydrogen was supplied so that the hydrogen concentration in the gas phase portion was 10.8 mol%, and the polymerization was carried out at a polymerization temperature of 68 ° C. and a pressure of 3.2 MPa / G.

Next, the obtained slurry was transferred to a liquid transfer pipe having an internal volume of 2.4 L, and this slurry was gasified to perform air-solid separation. Then, polypropylene homopolymer powder was sent to a gas phase polymerizer having an internal volume of 480 L, and ethylene / propylene block copolymerization was performed. Propylene, ethylene, and hydrogen are continuously added so that the gas composition in the gas phase polymerizer is ethylene / (ethylene + propylene) = 0.44 (molar ratio) and hydrogen / ethylene = 0.12 (molar ratio). It was supplied and polymerized at a polymerization temperature of 70 ° C. and a pressure of 0.6 MPa / G.

Next, the obtained propylene-based block copolymer was vacuum-dried at 80 ° C. The MFR (230 ° C., 2.16 kg load) of this propylene / ethylene block copolymer (A-1) is 14 g / 10 minutes, and the amount of the decane-soluble portion (ethylene / propylene copolymer portion (A2)). Was 12% by mass, the ethylene content of the decane-soluble portion was 47 mol%, and the ultimate viscosity [η] of the decane-soluble portion was 2.8 dl / g.

In the examples and comparative examples, the following compounds were used as the components (B) to (G).

<Ethylene / α-olefin copolymer (B)>
Ethylene 1-butene random copolymer (manufactured by Mitsui Chemicals, Inc., Toughmer (registered trademark) A1050S, ethylene content = 83 mol%, MFR (230 ° C, 2.16 kg load) = 2 g / 10 minutes, density = 0. 862 g / cm ³ )

<Inorganic filler (C)>
Talc (manufactured by Hayashi Kasei Co., Ltd., trade name GHL-7. Average particle size 5.8 μm)

<Antioxidant (D)>
"D-1": Hindered phenolic antioxidant having a molecular weight of 1000 or more (pentaerythritol-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, manufactured by BASF Japan Co., Ltd., Irganox (Registered trademark) 1010, molecular weight = 1177.7)
"D-2": Hindered phenolic antioxidant (D-2) with a molecular weight of less than 1000 (Tris- (3,5-di-t-butyl-4-hydroxybenzyl) -isocyanurate, manufactured by BASF Japan Ltd. , Irganox® 3114, molecular weight = 784.0)
"DP": Phosphorus-based antioxidant (BASF Japan Ltd., Irgafos (registered trademark) 168)
"DS": Sulfur-based antioxidant (manufactured by Mitsubishi Chemical Corporation, trade name DMTP "Yoshitomi")

<Weather-resistant stabilizer (E)>
"E-1": A benzoate-based photostabilizer having a molecular weight of less than 1000 (2,4-di-t-butylphenyl-3,5-di-t-butyl-4-hydroxybenzoate, manufactured by BASF Japan Ltd., Tinuvin ( Registered trademark) 120, molecular weight = 438.7)
"E-2": Hindered amine-based photostabilizer with a molecular weight of less than 1000 (Tetrakis (1,2,2,6,6-pentamethyl-4-piperidyl) 1,2,3,4-butanetetracarboxylate, ADEKA CORPORATION Manufactured by, trade name LA-52, molecular weight = 847.2)

<Pigment (F)>
"F-1": Carbon black (manufactured by Orion Engineered Carbons, trade name HIBLACK 890B, average primary particle size = 15 nm)
"F-2": Titanium oxide (manufactured by The Chemours Company, trade name Ti-Pure R-104)
"F-3": In Examples 1 to 4 and Comparative Examples 2 to 5, the blue pigment (manufactured by Clariant, trade name PV Fast Blue A4R) was 0.05 parts by weight, and the green pigment (manufactured by Heubach) was a product. The name Vynamon Green 600734) was used in combination of 0.15 parts by weight.

<Fatty acid metal salt (G)>
Fatty acid metal salt (manufactured by NOF CORPORATION, trade name Magnesium stearate G)

<Examples 1 to 4, Comparative Examples 1 to 5>
Each component (A) to (G) is mixed in the blending amount (part by mass) shown in Table 1, and a cylinder temperature of 180 ° C. is used using a twin-screw extruder (manufactured by Japan Steel Works, Ltd., TEX® (registered trademark) 30α). , Screw rotation 750 rpm, extrusion amount 60 kg / h, extruded to obtain a filler-containing polypropylene resin composition.

Table 2 shows the physical characteristics of the injection-molded article (test piece) produced from the obtained filler-containing polypropylene-based resin composition.

As is clear from the results shown in Tables 1 and 2, in Examples 1 to 4, the rigidity and the Izod impact intensity at a low temperature (-30 ° C.) were exhibited in a very well-balanced manner. The deflection temperature under load was also very high. Therefore, it is also effective in maintaining rigidity at high temperatures. Further, the L value, the a value, and the b value became the target values described above, and a high-quality and good jet-blackness was exhibited. In addition, the weather resistance (SWOM) and the impact strength retention rate after the heat resistance test were high, and no cracks were generated.

In Comparative Example 1, since the green pigment or the blue pigment (F-3) was not blended, the L value, the a value, and the b value did not become the target values, and the jet blackness was not exhibited.

In Comparative Example 2, since the amount of the inorganic filler (C) blended was too small, it was inferior in terms of flexural modulus and Izod impact strength, and the physical property balance was poor. In addition, the deflection temperature under load was low, and it was inferior in terms of maintaining rigidity at high temperatures.

In Comparative Example 3, since the amount of the inorganic filler (C) blended is too large, the L value does not reach the target value even if the green pigment or the blue pigment (F-3) is blended, and good jet blackness is obtained. It did not appear.

In Comparative Example 4, a sulfur-based antioxidant (DS), which is generally excellent in improving heat resistance at high temperatures, was blended, but cracks occurred in the heat resistance test.

In Comparative Example 5, a phosphorus-based antioxidant (DP) was blended, but cracks were generated in the heat resistance test, and the impact strength retention rate after the heat resistance test was low.

As is clear from the above results, since the filler-containing polypropylene-based resin composition of the present invention has a specific composition, it is excellent in physical properties such as rigidity, impact resistance, and heat resistance. Further, a specific amount of the inorganic filler (C) is combined with a specific amount of three kinds of pigments (F-1), (F-2) and (F-3) [particularly the pigment (F-3)]. As a result, a high-quality and good jet-blackness is exhibited.

The filler-containing polypropylene-based resin composition of the present invention is useful as a molded material in various fields such as automobile exterior parts such as bumpers, side moldings, back doors, fenders, and back panels, household products, and home appliance parts. In particular, it can be suitably used for automobile exterior parts.

Claims (3)

70 to 100% by mass of the propylene homopolymer part (A1) and 0 to 30% by mass of the ethylene / propylene copolymer part (A2) having an ultimate viscosity [η] of 2.0 to 8.0 dl / g. 60 to 75 parts by mass of the propylene-based polymer (A) composed of (A1) and the component (A2) totaling 100% by mass).
Ethylene / α-olefin copolymer (B) (α-olefin has 3 to 10 carbon atoms) 0 to 5 parts by mass,
Inorganic filler (C) 25 to 35 parts by mass,
As the antioxidant (D), a hindered phenolic antioxidant (D-1) having a molecular weight of 1000 or more is 0.01 to 1.0 parts by mass, and a hindered phenolic antioxidant (D-2) having a molecular weight of less than 1000 is used. ) 0.01 to 1.0 parts by mass,
As the weather resistance stabilizer (E), a benzoate-based light stabilizer (E-1) having a molecular weight of less than 1000 (0.01 to 0.5 parts by mass) and a hindered amine-based light stabilizer (E-2) having a molecular weight of less than 1000 (E-2) 0. 01-0.5 parts by mass,
As the pigment (F), carbon black (F-1) 0.4 to 1.0 parts by mass, titanium oxide (F-2) 0.5 parts by mass or less, and a green pigment or a blue pigment (F-3). ) 0.05-0.5 parts by mass and
Fatty acid metal salt (G) 0.01 to 1.0 parts by mass [However, the total amount of the component (A), the component (B) and the component (C) is 100 parts by mass. ]
Filler-containing polypropylene-based resin composition containing. The filler-containing polypropylene-based resin composition according to claim 1, wherein the propylene-based polymer (A) is a propylene / ethylene block copolymer. An automobile exterior component obtained by injection molding the filler-containing polypropylene resin composition according to claim 1 or 2.