JPH0770383A - Polypropylene composition - Google Patents

Abstract

PURPOSE:To provide the title composition which can give a product excellent in rigidity and heat resistance and also excellent in impact resistance especially toughness. CONSTITUTION:The composition comprises polypropylene and a rubber component and satisfies the following requirements: (i) the melt flow rate (as measured according to ASTM, the same shall apply hereinbelow) is 10g/10min or above, (ii) the bending modulus is 20000kg/cm<2> or above, (iii) the Izod impact strength is 20kg.cm/cm or above, (iv) the heat distortion temperature is 135 deg.C or above; and (v) each propylene crystallite measures 5-20nm in the direction of c axis, 5-20nm in the direction of a axis and 5nm or above in the direction of b axis as measured by the broad-angle X-ray diffraction method and small-angle X-ray scattering method, the rubber component exists repeatedly as a continuous phase around each polypropylene crystallite in the direction of injection and the direction crossing it, and the average thickness of the rubber continuous phase is 0.5-3nm.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a polypropylene composition having excellent rigidity and heat resistance as well as impact resistance and toughness.

[0002]

TECHNICAL BACKGROUND OF THE INVENTION Crystalline polypropylene has rigidity,
Although it is excellent in heat resistance and surface gloss, it has a problem that it is inferior in impact resistance.

Therefore, various methods for improving the impact resistance of polypropylene have heretofore been proposed, for example, a method of blending crystalline polypropylene with a modifier such as polyethylene or a rubber-like substance is known. As such a rubber-like substance, an amorphous or low crystalline ethylene / propylene random copolymer (EPR), polyisobutylene, polybutadiene, etc. are generally used.

However, in order to improve the impact resistance by adding the rubber-like substance as described above, it is necessary to add a large amount of the rubber-like substance to polypropylene. However, a polypropylene composition containing a large amount of the rubber-like substance. Has improved impact resistance, but has a problem that rigidity, heat resistance, and surface hardness are significantly reduced.

Therefore, a polypropylene composition containing an inorganic filler such as talc for imparting rigidity in addition to the rubber-like substance as described above has been proposed (Japanese Patent Laid-Open Nos. 60-58459 and Sho-58459). 60-60154, JP-A-61-233048, JP-A-61-3
6348, JP-A-62-235350, JP-A-63-122751, JP-A-63-1503.
43, JP-A-1-149845, and JP-A-1
No. 204947, Japanese Patent Laid-Open No. 1-271450, etc.).

However, a polypropylene composition containing a large amount of a rubber-like substance has a limit in improving the rigidity by blending an inorganic filler, and it is difficult to use it in applications requiring high rigidity. There was a problem.

Therefore, it is desired to develop a polypropylene composition which has excellent rigidity and heat resistance as well as impact resistance and toughness. The present inventor has conducted research on such a polypropylene composition, and in order to obtain a polypropylene composition excellent in rigidity and heat resistance as well as in impact resistance, a polypropylene of a generally known type is used. Not a polymer alloy of
A rubber-like substance (rubber component) is used as a matrix, polypropylene (crystal component) is used as a disperse phase, and polypropylene microcrystals have a specific size in the a-axis, b-axis, and c-axis directions, and around polypropylene microcrystals. The present invention has been completed by finding that the rubber component present in 1) may be a continuous phase having a specific average thickness.

[0008]

OBJECTS OF THE INVENTION It is an object of the present invention to provide a composition containing polypropylene as a main component, which is excellent in rigidity, heat resistance, impact resistance, impact resistance and toughness.

[0009]

SUMMARY OF THE INVENTION The polypropylene composition of the present invention comprises
It is characterized by containing polypropylene and a rubber component and satisfying the following conditions.

(I) Melt flow rate measured according to ASTM D1238 (MFR: 230 ° C., 2.1
(Under a load of 6 kg) is 10 g / 10 minutes or more, (ii) AS
Flexural modulus (F measured according to TM D790
M) is 20,000 Kg / cm ² or more, and (iii) AST
The Izod impact strength (IZ) measured according to MD 256 is 20 kg · cm / cm or more, and (iv) ASTM
Heat distortion temperature (HDT) measured according to D648
Is 135 ° C. or higher, and (v) in the injection-molded product, the size of polypropylene crystallites measured by the wide-angle X-ray diffraction method and the X-ray small-angle scattering method is 5 in the c-axis direction.
nm to 20 nm, 5 nm to 20 nm in the a-axis direction, 5 nm or more in the b-axis direction, and (vi) in the injection-molded product, the rubber component is the above-mentioned polypropylene fine particles in the injection direction and the direction perpendicular to the injection direction. The rubber continuously exists around the crystal as a continuous phase, and the average thickness of the rubber continuous phase is 0.5 nm to 3 nm.

The above polypropylene composition has, for example, a melt flow rate (MFR: 230 ° C., 2.16 kg load) measured according to (A) (1) ASTM D1238 of 10 to 60 g / 10. min and (2) ambient temperature n- decane soluble component in an amount of 3 to 13 wt%, (3) polypropylene component, MFR is 20 to 80 g / 10 min, ¹³
The pentad isotacticity (I ₅ ) determined by the C-NMR method is 0.97 or more, and (4) the room temperature n-decane-soluble component has an intrinsic viscosity [η] of 4 to 12 dl / g, Propylene block copolymer 60-8 containing a constitutional unit derived from ethylene in an amount of 30-60 mol%
0% by weight and (B) (1) 60 to 9 constitutional units derived from ethylene
0 mol% and (2) decalin intrinsic viscosity [η] is 1.5
Is 3.5 dl / g, (3) the glass transition temperature (Tg) is -50 ° C or lower, or the melting point measured as the main peak by the DSC method is 90 ° C or lower, (4) X-ray Ethylene / α-olefin random copolymers 15 to 25 having a crystallinity of less than 20% measured by a diffraction method
A composition composed of wt% and (C) an inorganic filler of 5 to 15 wt% may be mentioned.

[0012]

DETAILED DESCRIPTION OF THE INVENTION The polypropylene composition according to the present invention will be specifically described below. The polypropylene composition according to the present invention contains polypropylene and a rubber component, and satisfies the following conditions.

(I) Melt flow rate measured according to ASTM D1238 (MFR: 230 ° C., 2.1
Under a load of 6 kg) is 10 g / 10 minutes or more, preferably 10
It is 50 g / 10 minutes.

(Ii) The flexural modulus (FM) measured according to ASTM D790 is 20000 Kg / cm ² or more, preferably 20000 to 25000 Kg / cm ² . (iii) The Izod impact strength (IZ) measured according to ASTM D256 is 20 kg · cm / cm or more, preferably 25 to 60 kg · cm / cm, more preferably 30 to 6
It is 0 kg · cm / cm.

(Iv) Heat distortion temperature (HD) measured according to ASTM D648 under a load of 4.6 Kg / cm ^2.
T) is 135 ° C. or higher. The polypropylene composition according to the present invention contains polypropylene and a rubber component. In an injection-molded product formed from this polypropylene composition, polypropylene is contained in the rubber component (matrix) in the a-axis direction and the b-axis direction. And has a structure dispersed as fine crystals having a specific size in the c-axis direction. An injection-molded article formed from such a polypropylene composition is analyzed by an X-ray diffraction method, an X-ray small angle scattering method and an electron microscope as described below. Have

(V) Polypropylene microcrystals obtained by X-ray diffraction and small-angle X-ray scattering are 5 nm to 20 nm in the c-axis direction, 5 nm to 20 nm in the a-axis direction, and 5 nm or more in the b-axis direction, preferably. Has a size of 5 nm to 100 nm, more preferably 5 nm to 30 nm.

(Vi) In this injection-molded article, the rubber component exists as a continuous phase around the polypropylene crystallites in the injection direction and the direction perpendicular to the injection direction, and the continuous phase of the rubber is present. Has an average thickness of 0.5n
m to 3 nm.

In the injection-molded article formed from the polypropylene composition according to the present invention as described above, the polypropylene microcrystals and the rubber component have a specific structure as described above, and are excellent in rigidity and heat resistance and resistant to heat. Excellent impact resistance and toughness.

An injection-molded product formed from a polypropylene composition containing a conventionally known polypropylene and an ethylene / propylene random copolymer has a property as specified in the present invention. A part of the crystal component is mixed with the rubber component, so that the rubber component has a structure constrained by the amorphous component of polypropylene. In such a polypropylene composition, the impact resistance improving effect is not sufficient, and as described above, in order to improve the impact resistance, a large amount of a rubber component (ethylene / propylene random copolymer) has been conventionally used in the polypropylene composition. Etc.) had to be included.

In the present invention, the size of the polypropylene microcrystals as described above is measured by the following X-ray diffraction method (measured using a RU-200A type X-ray diffractometer manufactured by Rigaku Denki Co., Ltd.). can do. In the following, the wavelength of X-ray is calculated as 1.5418Å.

Measurement of Size of Polypropylene Microcrystals The crystal size of polypropylene microcrystals in the b-axis direction and the a-axis direction can be determined from wide-angle X-ray diffraction intensity.

The size of the polypropylene crystallites is calculated from Scherrer's formula from the half width of the peaks of the polypropylene crystals based on the (040) plane and the (110) plane. (1) The size of the crystal in the b-axis direction is obtained from the half width of the (040) plane.

(2) The size of the crystal in the a-axis direction is (11
The value calculated by using Scherrer's formula from the half-width of the (0) plane was multiplied by the ratio of the length 21.99Å of the diagonal line of the a-b plane of the unit cell and the length 20.96Å of the b-axis length. Calculated as a value.

(3) The crystal size in the c-axis direction is the crystallinity (X%) measured by the X-ray diffraction method and the long period (Å) of homopolypropylene measured by the X-ray small angle scattering intensity. It is calculated by multiplying by (long cycle Å × X%).

The long period of this homopolypropylene is calculated according to the Bragg equation from the scattering angle at which a small-angle X-ray scattering intensity of homopolypropylene is measured and the peak is shown. Measurement of the thickness of the rubber phase The thickness of the rubber phase is determined as the difference between the two long periods as described below, which is measured according to the Bragg equation from the scattering angle at which the X-ray small angle scattering intensity peaks.

Long period measured on a composition consisting of a propylene block copolymer, an ethylene / α-olefin random copolymer and an inorganic filler. Homopolypropylene (MF of this homopolypropylene
The R value is equal to the MFR value of the polypropylene component of the propylene block copolymer in the above composition) and an inorganic filler (the type and amount of the inorganic filler are the same as the above composition). Long period measured for.

Determination of rubber continuous phase Since the rubber component is dyed when a sample section is dyed with ruthenic acid, it is observed with an electron microscope of 150,000 times.
Crystal (unstained area) -Rubber (stained area) -Crystal (unstained area)
Can be seen repeating. From this photograph, it is possible to determine whether or not it is a rubber continuous phase.

Next, an example of the polypropylene composition according to the present invention satisfying the above specific conditions will be described below. Although the composition of the polypropylene composition according to the present invention as described above is not limited, for example, (A) a propylene block copolymer as described below,
(B) an ethylene / α-olefin random copolymer,
It is preferably formed of (C) fine powder talc.

Each of these components will be specifically described. In (A) a propylene block copolymer present invention, the polypropylene, the specific propylene block copolymer is preferably used. This (A)
The propylene block copolymer preferably comprises a highly crystalline homopolypropylene component and an ethylene / propylene copolymer rubber component that is a room temperature (23 ° C.) n-decane soluble component, and satisfies the following conditions. Is desirable.

(1) Propylene block copolymer (A)
At 230 ° C. according to ASTM D1238, 2.
Melt flow rate (MF) measured under a load of 16 kg
R) is 10 to 60 g / 10 minutes, preferably 15 to 40 g
/ 10 minutes is desirable.

The polypropylene composition containing the propylene block copolymer (A) having the MFR value as described above is excellent in fluidity and can be easily molded into a large molded product. MFR
A polypropylene composition containing a propylene block copolymer having a ratio of less than 10 g / 10 min has low fluidity and poor moldability, and may not be able to be molded into a large product.
A polypropylene composition containing a propylene block copolymer having an R of more than 60 g / 10 min tends to be inferior in impact strength (IZ).

(2) Propylene block copolymer (A)
It is desirable to contain the 23 ° C n-decane-soluble component in an amount of 3 to 13% by weight, preferably 4 to 10% by weight. Propylene block copolymer (A) containing the rubber component (23 ° C. n-decane soluble component) in the above amount
The polypropylene composition containing is excellent in flexural modulus, impact strength and low temperature toughness. Note that the polypropylene composition containing a propylene block copolymer in which the amount of the rubber component is more than the above amount may be inferior in rigidity, while the rubber component is a polypropylene composition containing the propylene block copolymer in which the amount is less than the above amount. The product may be inferior in impact strength and low temperature toughness.

(3) The polypropylene component of the propylene block copolymer (A) has a melt flow rate (MFR) of
Is 20 to 200 g / 10 minutes, preferably 20 to 80 g /
It is preferably 10 minutes, more preferably 20 to 60 g / 10 minutes.

The polypropylene component is ¹³ C--N
The pentad isotacticity I ₅ obtained by the MR method is 0.97 or more, preferably 0.98 or more.

MFR of polypropylene component is 20 g / 10
A polypropylene composition containing a propylene block copolymer having a content of less than 60 minutes has low fluidity and poor moldability and may not be able to be molded into a large product, while the polypropylene component has a MFR of more than 200 g / 10 minutes. The polypropylene composition containing the copolymer has an impact strength (I
Z) may be inferior.

A polypropylene composition containing a propylene block copolymer having a polypropylene component I ₅ of less than 0.97 tends to have poor rigidity. (4) The 23 ° C. n-decane-soluble component of the propylene block copolymer (A) has an intrinsic viscosity [η] measured in 135 ° C. decalin of 4 to 12 dl / g, preferably 5 to 8 dl / g. Is desirable.

It is desirable that the 23 ° C. n-decane-soluble component contains a structural unit derived from ethylene in an amount of 30 to 60 mol%, preferably 35 to 45 mol%.

Less than 30 mol% of constitutional units derived from ethylene in the 23 ° C. n-decane-soluble component, or 6
A polypropylene composition containing more than 0 mol% of a propylene block copolymer may have poor impact strength (IZ).

The propylene block copolymer (A) used in the present invention comprises a structural unit derived from ethylene,
It is desirable to contain the copolymer in an amount of 2 to 9 mol%, preferably 2 to 8 mol%.

A polypropylene composition containing a propylene block copolymer in which the constitutional unit derived from ethylene is less than 2 mol% may be inferior in impact strength (IZ), and the constitutional unit exceeds 9 mol%. A polypropylene composition containing the propylene block copolymer may have poor rigidity.

The 23 ° C. n-decane-soluble component as described above was boiled with 5 g of a sample (propylene block copolymer).
It is a value calculated back from the weight of the solid phase measured by immersing it in 200 cc of n-decane for 5 hours, dissolving it, cooling it to room temperature, filtering the precipitated solid phase with a G4 glass filter, and drying it.

The content of the constituent unit derived from ethylene can be determined by measuring the propylene block copolymer or the n-decane-soluble component by a conventional method such as infrared spectroscopy or NMR.

The pentad isotacticity I ₅ is
Macromolec by A. Zambelli et al.
ules 6, 925 (1973) proposed method ¹³ C-N
It is the isotactic fraction in the pentad unit in the polypropylene molecular chain measured by the MR method (nuclear magnetic resonance method), and is the fraction in the propylene monomer unit in which five propylene units are continuously isotacticly bonded. .

Assignment of peaks in the above-mentioned NMR measurement is carried out based on the description in Macromolecules 8, 687 (1975). ¹³ C-NMR is a Fourier transform NMR [5
00MHz (at the time of hydrogen nucleus measurement)] device, frequency 1
By performing integrated measurement at 20,000 times at 25 MHz, it is possible to improve the signal detection limit to 0.001 and perform measurement.

The ethylene / propylene copolymer component (23 ° C. n-decane-soluble component) in the propylene block copolymer (A) used in the present invention is a component other than ethylene and propylene as long as the object of the present invention is not impaired. It may contain a structural unit derived from a polymerizable monomer.

As such other polymerizable monomer,
Specifically, for example, 1-butene, 1-pentene, 1-hexene,
Α-Olefin such as 1-heptene, 1-octene, 1-decene, 1-dodecene, 1-hexadodecene, 4-methyl-1-pentene, vinylcyclopentene, vinylcyclohexane,
Examples thereof include vinyl compounds such as vinyl norbornane, vinyl esters such as vinyl acetate, unsaturated organic acids such as maleic anhydride, and derivatives thereof.

The propylene block copolymer (A) used in the present invention has a rubber part which is a ternary copolymer of ethylene, propylene and another polymerizable monomer, and a rubber part which is a binary system of ethylene and propylene. It may be a mixture with a propylene block copolymer which is a copolymer.

The propylene block copolymer (A) used in the present invention is 3-methyl-1-butene, 3,3-dimethyl-1-butene, 3-methyl-1-pentene, 3-methyl-1. -Containing a homopolymer or copolymer such as hexene, 3,5,5-trimethyl-1-hexene, vinylcyclopentene, vinylcyclohexane, vinylnorbornane as a prepolymer formed by prepolymerization It is preferable because the crystallization rate of the polypropylene composition is increased.

The propylene block copolymer used in the present invention as described above can be produced by various methods, for example, using a stereoregular Ziegler-Natta catalyst. Specifically, it can be produced using a catalyst formed from a solid titanium catalyst component, an organometallic compound catalyst component, and optionally an electron donor.

In the present invention, as the solid titanium catalyst component, specifically, titanium trichloride or a titanium trichloride composition is supported on a carrier having a specific surface area of 100 m ² / g or more. , Or magnesium, halogen, an electron donor (preferably an aromatic carboxylic acid ester or an alkyl group-containing ether) and titanium as essential components, and these essential components have a specific surface area of 100 m ² /
A solid titanium catalyst component supported on a carrier of g or more is included. Of these, the latter solid titanium catalyst component is particularly preferable.

The organometallic compound catalyst component is preferably an organoaluminum compound, and specific examples of the organoaluminum compound include trialkylaluminum, dialkylaluminum halides, alkylaluminum sesquihalides, and alkylaluminum dihalides. The organoaluminum compound can be appropriately selected according to the type of titanium catalyst component used.

As the electron donor, an organic compound having a nitrogen atom, a phosphorus atom, a sulfur atom, a silicon atom, a boron atom or the like can be used, and an ester compound and an ether compound having the above-mentioned atoms are preferable. Is mentioned.

Such a catalyst may be further activated by a method such as co-pulverization, or the above olefin may be prepolymerized. (B) Ethylene / α-olefin random copolymer (B) The ethylene / α-olefin random copolymer used in the present invention has a structural unit derived from ethylene of 60 to 90 mol%, preferably 75 to It is contained in an amount of 85 mol%.

Specific examples of the α-olefin copolymerized with ethylene include propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-decene,
Examples include 1-dodecene and 1-hexadodecene.

Of these, 1-butene is preferred. These α-olefins may be a combination of two or more. Further, the ethylene / α-olefin random copolymer may contain a structural unit derived from a component other than ethylene and the α-olefin, for example, a structural unit derived from a diene or the like is contained as necessary. Good.

The constitutional unit derived from ethylene is 9
A polypropylene composition containing an ethylene random copolymer in an amount of 0 mol% or more may be inferior in impact resistance,
On the other hand, a polypropylene composition containing an ethylene-based random copolymer in which the constituent unit exceeds less than 60 mol% may have poor rigidity.

The ethylene / α-olefin random copolymer (B) used in the present invention preferably has the following physical properties. (2) Intrinsic viscosity [η] measured in decalin at 135 ℃
Is 1.5 to 3.5 dl / g, preferably 2.0 to 3.0
It is desirable that it is dl / g.

A polypropylene composition containing an ethylene / α-olefin random copolymer having an intrinsic viscosity [η] of less than 1.5 dl / g may be inferior in IZ impact strength, while the intrinsic viscosity [η] is 3. Ethylene / α exceeding 5 dl / g
-A polypropylene composition containing an olefin random copolymer may have low fluidity and poor moldability.

(3) The glass transition temperature is −50 ° C. or lower, preferably −55 ° C. or lower, or the melting point measured as the main peak by the DSC method is 90 ° C. or lower, preferably 80 ° C. or lower, especially It is preferably 70 ° C. or lower.

A polypropylene composition containing an ethylene / α-olefin random copolymer having a glass transition temperature of higher than −50 ° C. or a melting point of higher than 90 ° C. may have poor IZ impact strength.

(4) It is desirable that the crystallinity measured by the X-ray diffraction method is 20% or less, preferably 10% or less. A polypropylene composition containing an ethylene / α-olefin random copolymer having a crystallinity of more than 20% may be inferior in IZ impact strength.

The ethylene / α-olefin random copolymer (B) as described above is excellent in compatibility with polypropylene, and from this copolymer (B) and polypropylene,
A composition having excellent rigidity, impact resistance, and fluidity is formed. Moreover, an injection-molded article having an excellent appearance can be formed from such a polypropylene composition.

The ethylene / α-olefin random copolymer (B) as described above can be produced using a vanadium catalyst or a metallocene catalyst. (C) Fine powder talc As the fine powder talc (C) used in the present invention, a conventionally known one used as a modifier such as polyolefin can be used.

In the present invention, the fine powder talc (C) has an average particle size of 0.5 to 20 μm and a ratio of aspect ratio to aspect ratio of 2 times or more, preferably 10 times or more. Finely powdered talc is preferred. The fine powder talc (C) preferably has a content of particles having a particle diameter of 5 μm or more of 5% by weight or less.

The polypropylene composition according to the present invention comprises the above-mentioned (A) propylene block copolymer
~ 80% by weight, preferably 62-72% by weight,
(B) an ethylene / α-olefin random copolymer,
It is desirable to contain the inorganic filler (C) in an amount of 15 to 25% by weight, preferably 18 to 23% by weight, and an amount of 5 to 15% by weight, preferably 10 to 15% by weight.

The polypropylene composition according to the present invention can be obtained by a conventionally known method for preparing a resin composition from the above-mentioned respective components. Specifically, the respective components are simultaneously or sequentially added, for example, to Henschel. It is obtained by charging in a mixer, a V-type blender, a tumbler blender, a ribbon blender or the like, kneading, and then melt-kneading with a single-screw extruder, a multi-screw extruder, a kneader, a Banbury mixer or the like.

Among these, when a device having excellent kneading performance such as a multi-screw extruder, a kneader, a Banbury mixer, etc. is used, it is possible to obtain a high quality polypropylene composition in which the respective components are more uniformly dispersed. preferable.

An example of the polypropylene composition according to the present invention has been shown above, but the polypropylene composition according to the present invention is not limited to this example as long as it satisfies the specific conditions described above. .

The polypropylene composition of the present invention further comprises a heat-resistant stabilizer, an aromatic carboxylic aluminum salt, an aromatic phosphate ester salt, a nucleating agent such as dibenzylidene sorbitol, an ultraviolet ray, etc., within the range not impairing the object of the present invention. Absorbents, lubricants, antistatic agents, flame retardants, pigments, dyes, inorganic fillers other than fine powder talc, organic fillers, other polymers such as polyethylene (PE), propylene / ethylene random copolymer (EPR), etc. May be contained.

[0070]

The polypropylene composition according to the present invention is
Not only is it excellent in rigidity and heat resistance, but also has various physical properties such as impact resistance and toughness, as compared with conventionally known polypropylene compositions.

The injection-molded article formed from the polypropylene composition according to the present invention can be used in a wide variety of applications, and is particularly suitable for automotive interior / exterior applications such as bumpers.

[0072]

EXAMPLES Next, the present invention will be specifically described with reference to examples, but the present invention is not limited to these examples.

In the following examples, each physical property was measured as follows. (1) MFR: Measured according to ASTM D1238. Conditions: 230 ° C., 2.16 kg (2) Flexural modulus (FM): Measured according to ASTM D790.

Test piece 12.7 mm (width) × 6.4 mm (thickness)
× 127 mm (length) Span span 100 mm Bending speed 2 mm / min (3) Izod impact strength (IZ): ASTM D256
It was measured according to.

Temperature 23 ° C. Specimen 12.7 mm (width) × 6.4 mm (thickness) × 64 mm (length) Notch was machined (4) Heat distortion temperature (HDT) Measured according to ASTM D648.

Load 4.6 kg / cm ² (5) The sizes of polypropylene microcrystals in the a-axis direction, the b-axis direction and the c-axis direction were determined as described above.

(6) The rubber continuous phase was evaluated by electron microscopy as described above. (7) The thickness of the rubber phase in the injection-molded article formed from the polypropylene composition was determined as described above.

The X-ray diffraction was measured using a RU-200A type X-ray diffractometer manufactured by Rigaku Denki Co., Ltd. In addition, in the following Examples and Comparative Examples, the components used in preparing the polypropylene compositions are as follows. (A) Polypropylene block PP1: Propylene block copolymer (1) MFR; 20 g / 10 min (2) Room temperature n-decane soluble component; 5 wt% (3) MFR of polypropylene component; 28 g / 10 min, (4) ) I ₅ ; 0.98 (5) Intrinsic viscosity [η] of the n-decane-soluble component at room temperature [η]; 5.5 dl
/ G (6) Structural unit derived from ethylene; 40 mol% Homo PP: Homopolypropylene MFR; 20 g / 10 min I ₅ ; 0.98 (B) Ethylene / α-olefin random copolymer EBR-1: Ethylene / 1-Butene random copolymer Structural unit derived from ethylene; 81 mol% Intrinsic viscosity [η]; 2.5 dl / g Glass transition temperature (Tg); -64 ° C Crystallinity; 5% (C) Talc : Average particle size; 2.5 μm content of particles having a particle size of 5 μm or more; 3 wt%

[0079]

Examples 1 and 2 The components shown in Table 1 were dry blended and kneaded at 200 ° C. using a twin-screw extruder to obtain polypropylene compositions.

From each polypropylene composition obtained, an ASTM test piece was molded by an injection molding machine under the conditions of a resin temperature of 200 ° C. and a mold temperature of 40 ° C., and the physical properties of each test piece were measured as described above. .

The results are shown in Table 1. In the injection-molded article obtained in Example 1, the size of polypropylene crystallites is c
The axial direction is 9.8 nm, the a-axis direction is 17 nm, and the b-axis direction is 18 nm. In the injection direction and the direction perpendicular to the injection direction, there is a continuous phase of rubber around the crystallites, and the average of the rubber phase is It had a phase structure in which a structure having a thickness of 1.22 nm was repeated.

[0082]

COMPARATIVE EXAMPLES 1-2 The ASTM test pieces were molded in the same manner as in Example 1 except that the polypropylene composition shown in Table 1 was used, and the physical properties of each test piece were measured.

The results are shown in Table 1.

[0084]

[Table 1]

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mikio Hashimoto 6-1-2 Waki, Waki-cho, Kuga-gun, Yamaguchi Prefecture Mitsui Petrochemical Industry Co., Ltd. 6-1-2 Waki Kimachi Mitsui Petrochemical Industry Co., Ltd.

Claims (2)

[Claims] 1. A polypropylene composition containing polypropylene and a rubber component, which satisfies the following conditions: (i) Melt flow rate measured according to ASTM D1238 (MFR: 230 ° C., 2.16 kg load)
Is 10 g / 10 min or more, (ii) the flexural modulus (FM) measured according to ASTM D790 is 20000 Kg / cm ² or more, and (iii) measured according to ASTM D256. The Izod impact strength (IZ) is 20 kg · cm / cm or more, (iv) the heat distortion temperature (HDT) measured according to ASTM D648 is 135 ° C. or more, and (v) its injection molded product. At wide-angle X-ray diffraction and X
The size of polypropylene crystallites measured by the small-angle linear scattering method is 5 nm to 20 nm in the c-axis direction and 5 nm to 20 in the a-axis direction.
nm, 5 nm or more in the b-axis direction, and (vi) in the injection-molded product, the rubber component is present as a continuous phase around the polypropylene crystallites in the injection direction and the direction perpendicular to the injection direction. Along with
The average thickness of this rubber continuous phase is 0.5 nm to 3 nm. 2. The polypropylene composition has a melt flow rate (MFR: 230 ° C., 2.16 kg load) measured according to (A) (1) ASTM D1238 of 10 to 60 g / 10 minutes, (2) ambient temperature n- decane soluble component in an amount of 3 to 13 wt%, (3) polypropylene component, MFR is 20 to 80 g / 10 min, ¹³
The pentad isotacticity (I ₅ ) determined by the C-NMR method is 0.97 or more, and (4) the room temperature n-decane-soluble component has an intrinsic viscosity [η] of 4 to 12 dl / g, Propylene block copolymer 60-8 containing a constitutional unit derived from ethylene in an amount of 30-60 mol%
5% by weight and (B) (1) 60 to 9 constitutional units derived from ethylene
0 mol% and (2) decalin intrinsic viscosity [η] is 1.5
Is 3.5 dl / g, (3) the glass transition temperature (Tg) is -50 ° C or lower, or the melting point measured as the main peak by the DSC method is 90 ° C or lower, (4) X-ray Ethylene / α-olefin random copolymers 15 to 25 having a crystallinity of less than 20% measured by a diffraction method
The composition according to claim 1, wherein the composition comprises 5% by weight and (C) an inorganic filler of 5 to 15% by weight.