JPH0971712A - Propylene polymer composition for automotive interior material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a propylene polymer composition which has excellent moldability and can give an automotive interior materiel excellent in hardness, rigidity and impact strength by mixing a specified propylene block copolymer with a specified ethylene/1-octene random copolymer and talc. SOLUTION: This propylene polymer composition for an automotive interior materiel comprises 53-61wt.% propylene block copolymer having an MFR of 50-400g/10min, an [η] of 5-10dl/g, containing 3-13wt.% component soluble in n-decane at ordinary temperature and having an MFR of the propylene component of 60-450g/10min and an Is of 0.97 or above, 21-25wt.% ethylene/1-octene random copolymer [B] having a content of 1-octene units of 7-15mol%, an [η]of 1.5-3.5dl/g, a Tg of-50 deg.C or below, and a Tm of 90 deg.C or below and 18-22wt.% talc. The composition has an MFR of 28g/10min or above, and FM of 25,000kg/cm<2> or above, an IZ of 20kg.cm/cm or above and an R scale of 85 or above and gives an injection molding having crystallites of 5-20nm indirections of the (c) and (a) axes.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD OF THE INVENTION The present invention relates to a propylene polymer composition for automobile interior materials, and more specifically, it forms a molded article having excellent moldability and heat resistance as well as hardness and rigidity as well as impact strength. And a propylene polymer composition for automobile interior materials.

[0002]

BACKGROUND OF THE INVENTION Crystalline polypropylene has hardness,
Although it has excellent rigidity, heat resistance, surface gloss, etc., it has a problem of poor impact resistance, especially polypropylene used for automotive interior materials such as trims, instrumental panels, and column covers. Improvement of impact resistance is desired.

Therefore, various polypropylene compositions having improved impact resistance have been proposed in the past. For example, a polypropylene composition in which a modifier such as polyethylene or a rubber-like substance is mixed with crystalline polypropylene is known. ing. 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. A polypropylene composition containing a large amount of a rubber-like substance has improved impact resistance, but its rigidity, heat resistance and surface hardness are greatly reduced.

Therefore, a polypropylene composition has been proposed which contains an inorganic filler such as talc for imparting rigidity together with the above rubber-like substance. However, the polypropylene composition containing a large amount of a rubber-like substance has a problem in that it cannot be used for applications requiring high rigidity because there is a limit in improving rigidity by blending an inorganic filler.

[0006]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above-mentioned prior art, and provides a propylene polymer composition for automobile interior materials which is excellent in hardness and rigidity, and is excellent in impact strength and moldability. It is intended to be provided.

[0007]

SUMMARY OF THE INVENTION The propylene polymer composition for automobile interior materials according to the present invention has a melt flow rate (MFR: 230 ° C., 2.16 kg load) measured according to [A] (1) ASTM D1238. 50 to 400 g / 10 minutes, (2) the room temperature n-decane soluble component is contained in an amount of 3 to 13% by weight, and the room temperature n-decane soluble component has an intrinsic viscosity [η] of 5 to 10 dl / g,
And a unit derived from ethylene in an amount of 30 to 50 mol%, (3) a polypropylene component having a melt flow rate of 60 to 450 g / 10 min, and a pentad isotacticity determined by a ¹³ C-NMR method. It contains 53 to 61% by weight of a propylene block copolymer having a city (I ₅ ) of 0.97 or more and a unit derived from [B] (1) 1-octene in an amount of 7 to 15% by mole, (2) Intrinsic viscosity [η] is 1.5-3.5dl
21 to 25 parts by weight of ethylene / 1-octene random copolymer having a glass transition point (Tg) of −50 ° C. or lower and (4) a melting point (Tm) of 90 ° C. or lower. %
And [C] talc 18 to 22% by weight, (i) the melt flow rate (MFR) is 28 g / 10 minutes or more, and (i)
i) Flexural modulus (FM) is 25,000 kg / cm ² or more, and (iii) Izod impact strength (IZ; 23 ° C.) is 20.
kg · cm / cm or more, (iv) Rockwell hardness (R scale) of 85 or more, and (v) in the injection-molded product of the propylene polymer composition, the propylene block copolymer [A] component is 5n in the c-axis direction with a transmission electron microscope
It is characterized by being observed as fine crystals having a size of m to 20 nm and a size of 5 to 20 nm in the a-axis direction.

[0008]

DETAILED DESCRIPTION OF THE INVENTION The propylene polymer composition for automobile interior materials according to the present invention will be specifically described below.
In the present invention, the term "polymerization" may be used to mean not only homopolymerization but also copolymerization,
The term "polymer" may be used to mean not only a homopolymer but also a copolymer.

The propylene polymer composition for automobile interior materials according to the present invention comprises a specific [A] propylene block copolymer, [B] ethylene / 1-octene random copolymer and [C] talc. It is formed and has the physical properties described below, and the injection-molded product has a specific microstructure. Hereinafter, each component forming the propylene polymer composition for automobile interior materials according to the present invention will be described first.

[A] Propylene Block Copolymer In the present invention, a specific propylene block copolymer having the following characteristics is used. This propylene block copolymer is preferably formed from a highly crystalline polypropylene component and an ethylene / propylene copolymer rubber component which is a room temperature (23 ° C.) n-decane soluble component.

(1) Melt flow rate (MFR; ASTM) of the propylene block copolymer used in the present invention
D1238, 230 ° C, 2.16 kg load) is 50 ~
400 g / 10 minutes, preferably 50 to 90 g / 10 minutes.
From the propylene block copolymer having such an MFR value, a propylene polymer composition having excellent fluidity and capable of molding a large product can be obtained. A composition formed from a propylene block copolymer having an MFR value of more than 400 g / 10 minutes may be inferior in impact resistance (IZ impact strength).

(2) The propylene block copolymer used in the present invention contains n-decane soluble component at room temperature (23 ° C.) in an amount of 3 to 3.
It is contained in an amount of 13% by weight, preferably 4 to 10% by weight. This room temperature n-decane soluble component has an intrinsic viscosity [η] (13
(Measured in decalin at 5 ° C.) is 5 to 10 dl / g, preferably 5 to 8 dl / g. The room temperature n-decane-soluble component contains a unit derived from ethylene in an amount of 30 to 50 mol%, preferably 35 to 45 mol%. This room temperature
The n-decane-soluble component is a rubber component in the propylene block copolymer [A], and preferably an ethylene / propylene copolymer rubber component.

The propylene block copolymer used in the present invention contains a rubber component containing a specific amount of ethylene units (normal temperature n-decane-soluble component) in a specific amount and having a high intrinsic viscosity as described above. Therefore, from such a propylene block copolymer, a propylene polymer composition having excellent impact resistance (IZ impact strength) and excellent rigidity can be formed.

The normal temperature of the propylene block copolymer n-
The content of the decane-soluble component was determined by immersing 5 g of the sample (propylene block copolymer) in 200 cc of boiling n-decane for 5 hours to dissolve it, then cooling it to room temperature, and separating the precipitated solid phase into G4.
It can be determined by back-calculating from the solid-phase weight measured after drying with a glass filter and drying.

The room temperature n-decane soluble component of the propylene block copolymer [A] used in the present invention contains a unit derived from a polymerizable compound other than ethylene and propylene within a range not impairing the object of the present invention. You may have.
Specific examples of such other polymerizable compound include 1-butene, 1-pentene, 1-hexene, 1-heptene, and 1-butene.
Octene, 1-decene, 1-dodecene, 1-hexadodecene,
Examples thereof include α-olefins such as 4-methyl-1-pentene, vinyl compounds such as vinylcyclopentene, vinylcyclohexane and vinylnorbornane, vinyl esters such as vinyl acetate, unsaturated organic acids such as maleic anhydride, and derivatives thereof.

(3) The melt flow rate (MFR) of the polypropylene component of the propylene block copolymer used in the present invention is 60 to 450 g / 10 minutes, preferably 80 to
It is 350 g / 10 minutes.

The polypropylene component of ¹³ C-NM
The pentad isotacticity I ₅ obtained by the R method is 0.97 or more, preferably 0.973 or more.
The pentad isotacticity I ₅ was developed by A. Zambelli et al. In Macromolecules 6, 925.
(1973), that is, ¹³ C-NMR method (nuclear magnetic resonance method), is the isotactic fraction of pentad units in the polypropylene molecular chain. It is the fraction of propylene monomer units that are tactically 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
It is possible to improve the signal detection limit to 0.001 by performing integrated measurement at 25 MHz and 20000 times. A composition having excellent rigidity can be obtained from a propylene block copolymer having a polypropylene component I ₅ having such a value.

The [A] propylene block copolymer used in the present invention as described above contains a unit derived from ethylene in an amount of 2 to 9 mol%, preferably 2 to 8 mol% in the copolymer.
It is desirable to contain it in an amount of mol%. The content of the 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 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 of hexene, 3,5,5-trimethyl-1-hexene, vinylcyclopentene, vinylcyclohexane, vinylnorbornane, etc., as a prepolymer formed by prepolymerization, for example. , The crystallization rate is high.

The propylene block copolymer used in the present invention as described above can be produced by various methods. For example, it can be produced using a stereoregular catalyst. Specifically, it can be produced using a catalyst formed from a solid titanium catalyst component, an organometallic compound catalyst component, and, if necessary, 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 the 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-grinding, or the above olefin may be prepolymerized.

[B] Ethylene / 1-octene Random Copolymer
Combined (1) The ethylene / 1-octene random copolymer used in the present invention has 7 to 10 structural units derived from 1-octene.
It is contained in an amount of 15 mol%, preferably 8 to 13 mol%.

(2) The intrinsic viscosity [η] of the ethylene / 1-octene random copolymer used in the present invention (measured in decalin at 135 ° C.) is 1.5 to 3.5 dl / g, preferably 1 It is 0.5 to 3.0 dl / g.

(3) The glass transition temperature (Tg) of the ethylene / 1-octene random copolymer used in the present invention is −
It is 50 ° C. or lower, preferably −55 ° C. or lower. (4) The melting point (Tm) of the ethylene / 1-octene random copolymer is 90 ° C or lower, preferably 85 ° C or lower.
This melting point is measured as a main peak by the DSC method.

The parameter (B value) showing the randomness of the copolymerized monomer chain distribution of the ethylene / 1-octene random copolymer used in the present invention is preferably 1.0 to 1.4. The B value in such a [B] ethylene / 1-octene random copolymer is determined from the ¹³ C-NMR spectrum and the following formula.

[0030]

[Equation 1]

(In the formula, P _E and P _O represent the mole fraction of the ethylene component and the mole fraction of the 1-octene component contained in the ethylene / 1-octene copolymer, respectively, and P _OE
Indicates the mole fraction of 1-octene-ethylene chains in the total dyad chain. ) A polypropylene composition containing an ethylene / 1-octene random copolymer having a B value of less than 1.0 tends to have low impact resistance.

The density of the ethylene / 1-octene random copolymer used in the present invention is 0.875 to 0.895 g /
cm ³ , preferably 0.875 to 0.890 g / c
m is ^3. When the density is 0.875 g / cm ³ or less,
The hardness of the PP composition is not sufficient, and the density is 0.89.
If it is 5 g / cm ³ or more, impact resistance may not be exhibited.

The ethylene / 1-octene random copolymer as described above is excellent in compatibility with polypropylene, and the polypropylene composition containing this copolymer is excellent in rigidity and impact resistance. Moreover, since it is also excellent in fluidity, it is possible to form a molded product having an excellent appearance.

The ethylene / 1-octene random copolymer as described above can be produced using a known vanadium catalyst or metallocene catalyst. [C] Talc In the present invention, talc [C] has an average particle size of 0.2 to 3
Finely powdered talc with a particle size of 0.2 μm to 0.2 μm is preferably used.

In this talc, the content of particles having an average particle size of 5 μm or more is 10% by weight or less, preferably 8% by weight or less. The average particle size of talc can be measured by a liquid phase sedimentation method. In the present invention, among such talcs, talc having an average value of the aspect ratio (indicating the ratio of the length or the length in the length or width) of 3 or more, particularly 4 or more is preferably used.

The talc used in the present invention may be untreated or may be surface-treated in advance. As an example of this surface treatment, specifically, a silane coupling agent,
Chemical or physical treatment using a treating agent such as higher fatty acid, fatty acid metal salt, unsaturated organic acid, organic titanate, resin acid, polyethylene glycol and the like can be mentioned.

By using talc which has been subjected to such a surface treatment, a propylene polymer composition excellent in weld strength, coatability and moldability can be obtained. Propylene polymer composition for automobile interior materials The propylene polymer composition for automobile interior materials according to the present invention comprises the above-mentioned [A] propylene block copolymer and [B] ethylene / 1-butene random copolymer. When,
53 to 61% by weight, preferably 56 to 60% by weight of [C] talc and [A] propylene block copolymer.
[B] ethylene / 1-butene random copolymer (EOR) in an amount of 21% by weight, preferably 21 to 25% by weight.
[C] talc in an amount of 23% by weight, 18 to 22% by weight
It is contained in the amount of.

The propylene polymer composition for automobile interior materials according to the present invention can be obtained by kneading the respective components in the above amounts. As mentioned above, the EOR [B] used in the present invention is It has excellent compatibility with the propylene block copolymer [A], and is excellent in heat resistance from the propylene block copolymer [A] and EOR [B] and has excellent hardness, rigidity and impact strength. An excellent molded article can be formed. In addition, this propylene polymer composition is also excellent in moldability and can form a molded product having an excellent appearance.

Specifically, the propylene polymer composition for automobile interior materials according to the present invention has the following characteristics. (i) Melt flow rate (MFR) (ASTM D12
38; 230 ° C., under 2.16 kg load) is 28 g / 10 min or more, preferably 30 to 400 g / 10 min, and (ii) flexural modulus (FM) (ASTM D-790) is
25,000 kg / cm ² or more, preferably 25,000 to 270
00 kg / cm ² , and (iii) Izod impact strength (IZ) (ASTM D-2
56) is 20 kg · cm / cm or more, and (iv) Rockwell hardness (HR) (ASTM D-64
8) is 85 or more. Thus, the propylene polymer composition for automobile interior materials according to the present invention is excellent in rigidity, hardness, impact strength and the like. (v) Furthermore, in the injection molded article of the propylene polymer composition,
The propylene block copolymer [A] component is observed by a transmission electron microscope as fine crystals having a size of 5 nm to 20 nm in the c-axis direction and 5 nm to 20 nm in the a-axis direction.

In the present invention, the observation of the propylene block copolymer [A] fine crystals in the injection-molded article by such a transmission electron microscope (TEM) is carried out as follows. A sample for phase structure observation taken from the central part of an injection-molded product (square plate) of a propylene polymer-based composition was immersed in a RuO ₄ (ruthenic acid) aqueous solution at room temperature for 16 to 24 hours, and then,
Using an ultramicrotome at room temperature, T-500-2
Make an ultrathin film slice with a thickness of 000Å. This section is observed using a transmission electron microscope H-8100 manufactured by Hitachi, Ltd., 200 kV, and the sizes of the propylene block copolymer [A] microcrystals of the injection molded product in the a-axis direction and the c-axis direction are determined. . At this time, observation is performed from a direction perpendicular to the resin flow direction at the time of injection molding and parallel to the thickness direction of the injection test piece.

FIG. 1 shows a transmission electron microscope (TEM) photograph observed for an injection-molded article of the propylene polymer-based composition for an automobile interior material according to the present invention, and FIG. 2 shows crystals observed in this photograph. The schematic diagram of a structure is shown.

As described above, in the injection-molded article of the propylene polymer-based composition for automobile interior materials according to the present invention, the propylene block copolymer [A] component forms fine crystals, and the crystalline portion and the amorphous portion are separated from each other. It forms a dispersed structure at the nanometer level, forming a polymer alloy like a molecular composite.

The propylene polymer composition which forms such a microcrystalline structure when injection molded has excellent hardness,
Mechanical strength such as rigidity and impact resistance can be exhibited. The propylene polymer composition for automobile interior materials according to the present invention is a propylene block copolymer [A] as described above.
And ethylene / 1-octene random copolymer [B] and talc [C] can be prepared by kneading by a method generally known as a kneading method for resin compositions.

At this time, a kneading device such as a single-screw extruder, a twin-screw extruder, a twin-screw kneader, a Banbury mixer, or a roll can be used. A propylene polymer composition obtained as a kneaded product by kneading each of the above components with a kneading device such as an extruder is usually molded into pellets for use.

In the present invention, the order of adding the components [A], [B] and [C] to the kneading device at the time of preparing the propylene polymer composition is not limited and may be the same or different. In the present invention, the propylene block copolymer [A], EOR [B], and talc [C] are used in advance as EOR.
A master batch containing [B] and talc [C] at high concentrations was prepared, and the master batch was diluted with the propylene block copolymer [A] to be blended and molded, and finally obtained. It is also possible to prepare a propylene polymer composition having the above composition.

Each of the components used in the present invention as described above is excellent in kneading property and can easily form a propylene polymer composition. The propylene polymer composition for an automobile interior material according to the present invention has the characteristics as described above, and is compared with a conventionally known composition of a propylene polymer or a propylene polymer and an ethylene / propylene copolymer. Thus, it is possible to form a molded article having excellent rigidity and impact strength. Further, this propylene polymer composition can form a molded product excellent in coating property, dimensional stability and appearance.

The propylene polymer composition according to the present invention comprises
In particular, it is used after being molded into automobile interior materials such as trims, instrumental panels, and column covers. Furthermore, the propylene polymer composition for automobile interior materials according to the present invention may contain various additives. As such additives, specifically, phenol-based, sulfur-based,
Antioxidants such as phosphorus, lubricants, antistatic agents, dispersants,
Copper damage inhibitor, neutralizing agent, foaming agent, plasticizer, antifoaming agent, flame retardant, crosslinking agent, flowability improving agent such as peroxide, ultraviolet absorber, light resistance stabilizer, weld strength improving agent and the like. be able to. The propylene polymer composition, by containing the additives as described above, to form a molded article having further improved physical property balance, durability, paintability, printability, scratch resistance, molding processability, etc. You can

The propylene polymer composition for automobile interior materials according to the present invention may contain a nucleating agent. As the nucleating agent, various conventionally known nucleating agents can be used without any particular limitation. Among them, the following nucleating agents are preferable.

[0049]

Embedded image

(In the formula, R ¹ is oxygen, sulfur or carbon number 1
A 10 hydrocarbon group, R ^2, R ³ is hydrogen or a hydrocarbon group having 1 to 10 carbon atoms, R ^2, R ³ may be heterologous be homologous, R ² to each other , R ^{3 and} R ²
And R ³ may combine to form a ring, and M is 1 to
It is a trivalent metal atom, and n is an integer of 1 to 3. ) Specifically, sodium-2,2'-methylene-bis (4,6-di-
(t-butylphenyl) phosphate, sodium-2,2'-
Ethylidene-bis (4,6-di-t-butylphenyl) phosphate, lithium-2,2'-methylene-bis- (4,6-di-t-butylphenyl) phosphate, lithium-2,2 ' -Ethylidene-bis (4,6-di-t-butylphenyl) phosphate, sodium-2,2'-ethylidene-bis (4-i-propyl-
6-t-butylphenyl) phosphate, lithium-2,2'-
Methylene-bis (4-methyl-6-t-butylphenyl) phosphate, lithium-2,2'-methylene-bis (4-ethyl-6-
t-butylphenyl) phosphate, calcium-bis [2,2'-thiobis (4-methyl-6-t-butylphenyl) phosphate], calcium-bis [2,2'-thiobis (4-ethyl-6 -t-butylphenyl) phosphate], calcium-bis [2,2'-thiobis- (4,6-di-t-butylphenyl) phosphate], magnesium-bis [2,2'-thiobis (4, 6-di-t-butylphenyl) phosphate],
Magnesium-bis [2,2'-thiobis- (4-t-octylphenyl) phosphate], sodium-2,2'-butylidene-bis (4,6-di-methylphenyl) phosphate, sodium-2, 2'-butylidene-bis (4,6-di-t-butylphenyl) phosphate, sodium-2,2'-t-octylmethylene-bis (4,6-di-methylphenyl) phosphate, sodium-2 , 2'-t-octylmethylene-bis (4,6-
Di-t-butylphenyl) phosphate, calcium
Bis- (2,2'-methylene-bis (4,6-di-t-butylphenyl) phosphate), magnesium-bis [2,2'-methylene-bis (4,6-di-t-butylphenyl) ) Phosphate], barium-bis [2,2'-methylene-bis (4,6-di-t-
Butylphenyl) phosphate], sodium-2,2'-
Methylene-bis (4-methyl-6-t-butylphenyl) phosphate, sodium-2,2'-methylene-bis (4-ethyl-
6-t-butylphenyl) phosphate, sodium (4,
4'-dimethyl-5,6'-di-t-butyl-2,2'-biphenyl) phosphate, calcium-bis [(4,4'-dimethyl-6,6'-
Di-t-butyl-2,2'-biphenyl) phosphate], sodium-2,2'-ethylidene-bis (4-m-butyl-6-t-butylphenyl) phosphate, sodium-2,2 ' -Methylene-bis (4,6-di-methylphenyl) phosphate, sodium-2,2'-methylene-bis (4,6-di-ethylphenyl) phosphate, potassium-2,2'-ethylidene-bis (4,6-di-t-butylphenyl) phosphate, calcium-bis [2,2'-ethylidene-bis (4,6-di-t-butylphenyl) phosphate], magnesium-bis [2,2 ' -
Ethylidene-bis (4,6-di-t-butylphenyl) phosphate], barium-bis [2,2'-ethylidene-bis (4,6
-Di-t-butylphenyl) phosphate], aluminum-tris [2,2'-methylene-bis (4,6-di-t-butylfell) phosphate] and aluminum-tris [2,
2'-ethylidene-bis (4,6-di-t-butylphenyl) phosphate] and combinations thereof. Of these, sodium-2,2'-methylene-bis (4,6-di-t-butylphenyl) phosphate is preferred.

[0051]

Embedded image

(In the formula, R ⁴ is hydrogen or has 1 to 10 carbon atoms.
Wherein M is a monovalent to trivalent metal atom,
n is an integer of 1 to 3. ) Specifically, sodium-bis (4-t-butylphenyl)
Phosphate, sodium-bis (4-methylphenyl) phosphate, sodium-bis (4-ethylphenyl) phosphate, sodium-bis (4-i-propylphenyl) phosphate, sodium-bis (4-t-
Octylphenyl) phosphate, potassium-bis (4
-t-butylphenyl) phosphate, calcium-bis (4-t-butylphenyl) phosphate, magnesium
-Bis (4-t-butylphenyl) phosphate, lithium-bis (4-t-butylphenyl) phosphate, aluminum-bis (4-t-butylphenyl) phosphate and combinations thereof can be exemplified. . Of these, sodium-bis (4-t-butylphenyl) phosphate is preferred.

[0053]

Embedded image

(In the formula, R ⁵ is hydrogen or has 1 to 10 carbon atoms.
Is a hydrocarbon group. ) Specifically, 1,3,2,4-dibenzylidene sorbitol,
3-benzylidene-2,4-p-methylbenzylidene sorbitol, 1,3-benzylidene-2,4-p-ethylbenzylidene sorbitol, 1,3-p-methylbenzylidene-2,4-benzylidene sorbitol, 1,3- p-ethylbenzylidene-2,4-benzylidenesorbitol, 1,3-p-methylbenzylidene-2,4
-p-ethylbenzylidene sorbitol, 1,3-p-ethylbenzylidene-2,4-p-methylbenzylidene sorbitol,
1,3,2,4-di (p-methylbenzylidene) sorbitol, 1,
3,2,4-di (p-ethylbenzylidene) sorbitol, 1,3,
2,4-di (pn-propylbenzylidene) sorbitol, 1,
3,2,4-di (pi-propylbenzylidene) sorbitol,
1,3,2,4-di (pn-butylbenzylidene) sorbitol,
1,3,2,4-di (ps-butylbenzylidene) sorbitol,
1,3,2,4-di (pt-butylbenzylidene) sorbitol,
1,3,2,4-di (2 ', 4'-dimethylbenzylidene) sorbitol, 1,3,2,4-di (p-methoxybenzylidene) sorbitol, 1,3,2,4-di (p- Ethoxybenzylidene) sorbitol, 1,3-benzylidene-2-4-p-chlorobenzylidene sorbitol, 1,3-p-chlorobenzylidene-2,4-benzylidene sorbitol, 1,3-p-chlorobenzylidene-2,4- p-methylbenzylidene sorbitol, 1,3-p-chlorobenzylidene-2,4-p-ethylbenzylidene sorbitol, 1,3-p-
Methylbenzylidene-2,4-p-chlorobenzylidene sorbitol, 1,3-p-ethylbenzylidene-2,4-p-chlorobenzylidene sorbitol and 1,3,2,4-di (p-chlorobenzylidene) sorbitol and these Can be exemplified. Among these, 1,3,2,4-dibenzylidene sorbitol, 1,3,2,4-di (p-methylbenzylidene) sorbitol, 1,3,2,4-di (p-ethylbenzylidene) sorbitol , 1,3-p-chlorobenzylidene-2,4-p-
Methylbenzylidene sorbitol, 1,3,2,4-di (p-chlorobenzylidene) sorbitol and combinations thereof are preferred.

As the other nucleating agent, a metal salt of aromatic carboxylic acid or aliphatic carboxylic acid can be used. Specifically, aluminum benzoate, aluminum pt-butylbenzoate or sodium adipate, Examples thereof include sodium thiophenecarboxylate and sodium pyrrolecarboxylate. Further, an inorganic compound such as talc can also be used as a nucleating agent.

The nucleating agent as described above is used in an amount of 0.001 to 1 with respect to 100 parts by weight of the propylene block copolymer [A].
It may be contained in the composition in an amount of 0 parts by weight, preferably 0.01 to 5 parts by weight, particularly preferably 0.1 to 3 parts by weight. When the nucleating agent as described above is contained, the crystallization rate of the propylene polymer composition is improved, the crystal particles can be made finer at the time of crystallization, and the propylene polymer composition can be molded at a higher speed.

[0057]

Industrial Applicability The propylene polymer composition for automobile interior materials according to the present invention has specific physical properties as described above, is excellent in heat resistance, hardness, rigidity, impact strength, and has excellent moldability. And the injection-molded articles obtained from the composition have a specific microstructure.

Further, this propylene polymer composition can form a molded article excellent in coating property, dimensional stability and appearance. The propylene polymer composition according to the present invention is used by being molded into automobile interior materials such as trims, instrumental panels and column covers.

[0059]

EXAMPLES The present invention will now be specifically described with reference to examples, but the present invention is not limited to these examples.
In the following Examples and Comparative Examples, each property was measured as follows.

Melt Flow Rate (MFR) According to ASTM D-1238, 230 ° C., 2.1
It was measured under the condition of 6 kg (pellet).

Flexural Modulus (FM) Based on ASTM D-790, it was determined by conducting a bending test under the following conditions. Test piece: 6.4 mm (thickness) x 12.7 mm (width) x 12
7 mm (length) span: 100 mm Bending speed: 2 mm / min Measuring temperature: 23 ° C

Izod impact value (IZ) An Izod impact value (IZ) was determined by performing an impact test under the following conditions in accordance with ASTM D-256. Test piece; 12.7 mm (width) x 6.4 mm (thickness) x 64
mm (length) The notch was based on the machining measurement temperature; 23 ° C. tensile test (EL) ASTM D638-84. Specimen ASTM D638-84 No. 1 Dumbbell Distance between chucks 114 mm Temperature 23 ° C. Tensile speed 10 mm / min Rockwell hardness (HR) Based on ASTM D-648, a test was conducted under the following conditions to obtain. Scale: R test piece: 120 mm (length) x 130 mm (width) x 3.
0 mm (thickness) Measurement temperature; 23 ° C. Microcrystalline size of injection-molded article The injection-molded article of the propylene polymer composition was measured for the crystallite size of the propylene block copolymer component by the method described above.

The components used in the following examples and comparative examples are shown below. [A] Propylene Block Copolymer Table 1 shows the propylene block copolymer used in the examples and the propylene polymer used in the comparative examples.

[0064]

[Table 1] In Table 1, BPP-1 and BPP-2 are propylene block copolymers, and PP-3 is homopolypropylene.

[B] Ethylene / 1-octene random copolymer EOR-1: Unit derived from 1-octene 10 mol% [η] 1.6 dl / g Tg: -57 ° C, Tm: 75 ° C Density: 0. Unit derived from 886 g / cm ³ EOR-2: 1-octene 12 mol% [η] 1.6 dl / g Tg: −63 ° C., Tm: 60 ° C. Density 0.877 g / cm ³ [C] Talc average particle size 2.5 μm Content of particles having an average particle size of 5 μm or more; 3% by weight Other EPR: Ethylene propylene random copolymer [η] 1.7 dl / g Tg: −54 ° C. Density 0.867 g / cm ³

[0066]

Examples 1 to 5 The respective components were used in the amounts shown in Table 2 and kneaded and granulated by a twin-screw extruder at 200 ° C. to obtain propylene polymer compositions shown in Table 2. The obtained composition was treated under the conditions of a resin temperature of 230 ° C. and a mold temperature of 40 ° C. for 415 tons
Using an injection molding machine, an ASTM test piece and a 3 mm thick flat plate (120 mm × 130 mm) were molded and the above physical properties were measured. Table 2 shows the results.

[0067]

Comparative Examples 1 and 2 A propylene polymer composition was obtained in the same manner as in Example 1 except that the propylene polymer shown in Table 2 and each component shown in Table 2 were used. Table 2 shows the results.

[0068]

[Table 2]

[Brief description of drawings]

FIG. 1 shows a transmission electron microscope (TEM) photograph observed for an injection-molded article of a propylene polymer-based composition for an automobile interior material according to the present invention.

FIG. 2 shows a schematic diagram of a crystal structure observed in the electron microscope photograph of FIG.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Takeshi Nishio Inventor, Toyota City, Toyota City, Aichi Prefecture 1 Toyota Motor Co., Ltd. No. 2 Mitsui Petrochemical Industry Co., Ltd. (72) Inventor Satoru Moriya 6 1-2 Waki, Waki-cho, Kuga-gun, Yamaguchi Prefecture Mitsui Petrochemical Industry Co., Ltd.

Claims (1)

[Claims] 1. A melt flow rate (MFR: 230 ° C., measured according to [A] (1) ASTM D1238,
2.16kg load) is 50-400g / 10 minutes, (2)
Contains n-decane soluble component at room temperature in an amount of 3 to 13% by weight,
The room temperature n-decane soluble component has an intrinsic viscosity [η] of 5 to 10 dl
/ G, and the unit derived from ethylene is 30 to 5
(3) the polypropylene component has a melt flow rate of 60 to 450 g / 10 minutes, and ¹³ C
A propylene block copolymer having a pentad isotacticity (I ₅ ) of 0.97 or more as determined by NMR method of 53 to 61% by weight, and a unit derived from [B] (1) 1-octene of 7 Contained in an amount of up to 15 mol%, and (2) has an intrinsic viscosity [η] of 1.5 to 3.5 dl.
21 to 25 parts by weight of ethylene / 1-octene random copolymer having a glass transition point (Tg) of −50 ° C. or lower and (4) a melting point (Tm) of 90 ° C. or lower. %
And [C] talc 18 to 22% by weight, (i) the melt flow rate (MFR) is 28 g / 10 minutes or more, and (i)
i) Flexural modulus (FM) is 25,000 kg / cm ² or more, and (iii) Izod impact strength (IZ; 23 ° C.) is 20.
kg · cm / cm or more, (iv) Rockwell hardness (R scale) of 85 or more, and (v) in the injection-molded product of the propylene polymer composition, the propylene block copolymer [A] component is 5n in the c-axis direction with a transmission electron microscope
A propylene polymer composition for automobile interior materials, which is observed as fine crystals having a size of m to 20 nm and a size of 5 to 20 nm in the a-axis direction.