JPH093298A - Polypropylene composition - Google Patents

Abstract

PURPOSE: To obtain a polypropylene resin composition containing a specific propylene resin component, an antioxidant and an ultraviolet light stabilizer, having excellent impact resistance, hardness, rigidity, heat-resistance and moldability, capable of preventing the fogging on the room-side surface of a glass and useful as an interior material of automobile. CONSTITUTION: This polypropylene composition contains (I) 100 pts.wt. of a propylene resin composed of (A) 75-95wt.% of a propylene-ethylene block copolymer having a melt flow rate (MFR) of 25-40g/10min, (B) 0-10wt.% of an ethylene-propylene copolymer rubber having an MFR of 1-20g/10min and an ethylene-butene copolymer rubber having an MFR of 1-30g/10min and (C) talc having an average particle diameter of <=5μm, (II) 0.05-1 pt.wt. of a phenol-based antioxidant and (III) 0.1-1 pt.wt. of a hindered amine ultraviolet light stabilizer such as a polycondensation product of dimethyl succinate and 1-(2- hydroxyethyl)-4-hydroxy-2,2,6,6-tetramethylpiperidine.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polypropylene composition, and particularly to mechanical strength such as impact resistance, hardness and rigidity,
The present invention relates to a polypropylene composition which is excellent in moldability, heat resistance stability, and the like, and can prevent fogging on the inner surface of glass, and is suitable for automobile interiors.

[0002]

BACKGROUND OF THE INVENTION Polypropylene is widely used in various fields because it is lightweight and has excellent mechanical strength and the like. However, since it is inferior in impact resistance, various rubbers such as an ethylene-propylene copolymer rubber (EPR) and an inorganic filler such as talc are added to a propylene-ethylene block copolymer for the purpose of improving the impact resistance. A polypropylene resin composition has been proposed.

Japanese Unexamined Patent Publication (Kokai) No. 1-149845 discloses that (a) a boiling xylene-soluble component having an ethylene content of 20 to 60% by weight.
~ 12% by weight, the total ethylene content of the polymer is 1 to 7
% By weight and melt flow rate of 15 to 50 g / 10
Minutes propylene-ethylene block copolymer 59-74
% By weight, and (b) the propylene content is 20 to 60% by weight, and the Mooney viscosity ML _{1 + 4} (100 ° C.) is 100 to 150.
35% to 20% by weight of ethylene-propylene copolymer rubber, and (c) 3 to 6% by weight of talc having a specific surface area of 30,000 cm ² / g or more and an average particle size of 0.5 to 2.0 μm. Disclosed is a resin composition characterized by the following.

This resin composition contains fine talc having an average particle size of 1.0 μm or less as talc.
Fine talc easily forms agglomerates, and when agglomerates are formed, the balance of mechanical strength such as hardness, rigidity, and impact resistance at low temperature becomes poor. Further, when the specific surface area of talc is increased by using fine talc, the talc trapping effect (adsorptivity) is enhanced, and therefore, there is a problem that talc adsorbs various additives. Therefore, it has been attempted to improve the dispersibility of fine talc and suppress the adsorption of additives by subjecting talc to a surface treatment with an aminosilane-based treatment agent or a titanate-based treatment agent. However, there is a problem that it does not have a sufficient effect.

When polypropylene-based resin is used as an interior material for automobiles, in addition to mechanical properties such as impact resistance, moldability and light resistance are required. Therefore, a lubricant, an antioxidant, an ultraviolet absorber, a catalyst neutralizing agent, etc. are added to the polypropylene resin. However, when such an additive is used in the resin composition, there is a problem that a part of it is volatilized and the inner surface of the glass of the automobile is fogged.

Therefore, it is an object of the present invention to provide impact resistance,
It is an object of the present invention to provide a polypropylene-based composition which is excellent in mechanical strength such as hardness and rigidity, moldability, heat resistance stability and the like, and can prevent fogging on the inner surface of glass, and is suitable for automobile interiors.

[0007]

Means for Solving the Problems As a result of intensive studies in view of the above objects, the proportion and intrinsic viscosity of the propylene-ethylene copolymerized portion and the ethylene content of the propylene-ethylene copolymerized portion are within a predetermined range, and A propylene-ethylene block copolymer was produced so that a certain relationship was established between the heat of fusion of the propylene homopolymer portion and the melt flow rate, and an ethylene-propylene copolymer rubber and an ethylene-butene copolymer rubber were prepared using the propylene-ethylene block copolymer. , Talc, phenolic antioxidants and hindered amine ultraviolet stabilizers are added to give impact resistance, hardness,
It was found that a polypropylene-based composition excellent in mechanical strength such as rigidity, moldability, heat stability, etc., and capable of preventing fogging on the inner surface of glass and suitable for automobile interiors can be obtained, and conceived the present invention. did.

That is, the polypropylene composition of the present invention comprises (a) 75 to 95% by weight of a propylene-ethylene block copolymer having a melt flow rate (MFR) of 25 to 40 g / 10 minutes, and (b) MFR1. ~ 20g / 10
Minutes ethylene-propylene copolymer rubber, and MFR1
~ 30 g / 10 min ethylene-butene copolymer rubber 0
10% by weight, and (c) talc 5-1 with an average particle size of 5 μm or less
5% by weight and the propylene-ethylene block copolymer (a) is 3 to 2 per 100% by weight.
0% by weight of propylene-ethylene copolymerized portion (intrinsic viscosity is 3 to 5 dl / g, ethylene content of the copolymerized portion is 3
It is 0 to 50% by weight. ), The heat of fusion (ΔH _m ) and M
FR is 100 parts by weight of a polypropylene resin component containing a propylene homopolymer portion satisfying a relational expression of ΔH _m ≧ 24.5 + 1.583 log MFR, and (d)
It is characterized by comprising 0.05 to 1 part by weight of a phenolic antioxidant and 0.1 to 1 part by weight of (e) a specific hindered amine ultraviolet stabilizer.

The present invention is described in detail below. [1] Each component of polypropylene-based composition (a) Propylene-ethylene block copolymer The propylene-ethylene block copolymer used in the present invention is preferably one synthesized by multistage polymerization.

In the multistage polymerization, propylene is first polymerized in the presence of a Ziegler catalyst or the like to form a crystalline propylene homopolymer part (which may contain a small amount of comonomer component), and ethylene + Switching to propylene produces a propylene-ethylene copolymerization moiety.

The propylene-ethylene block copolymer synthesized by the above multi-stage polymerization is substantially composed of a crystalline homopolypropylene portion, a propylene-ethylene copolymer portion and a small amount of a crystalline homopolyethylene portion. , Each part may exist as a single polymer, or each part may be in a bonded state. The above parts are basically composed of propylene and / or ethylene, but other α-
It may contain a small amount of an olefin or a diene monomer.

With respect to the content of each of the above-mentioned components, the crystalline homopolypropylene portion is 80 to 97% by weight, preferably 85 to 97% by weight, and the propylene-ethylene copolymerization portion is 3%, with the total of + being 100% by weight. -20% by weight, preferably 3-15% by weight. Even if it contains a crystalline homopolyethylene portion, its content is 3% by weight or less. When the propylene-ethylene copolymer portion is less than 3% by weight (when the crystalline homopolypropylene portion exceeds 97% by weight), the effect of improving mechanical strength and the like cannot be seen. On the other hand, when the propylene-ethylene copolymerized portion exceeds 20% by weight (when the crystalline homopolypropylene portion is less than 80% by weight), the rigidity and impact resistance decrease. The content of the propylene-ethylene copolymerized portion is determined by measuring the proportion of the soluble portion in cold xylene.

Regarding the above-mentioned crystalline homopolymer part,
It is necessary that the heat of fusion (ΔH _m ) and the MFR satisfy the relational expression ΔH _m ≧ 24.5 + 1.583 log MFR. ΔH _m <24.
In the case of 5 + 1.583 log MFR, rigidity and heat resistance are low.

The content of ethylene in the propylene-ethylene copolymerization portion is 30 to 50% by weight, preferably 35 to 50% by weight.
It is 45% by weight. If the ethylene content is less than 30% by weight or exceeds 50% by weight, the ductility is particularly insufficient.
The intrinsic viscosity [η] of the propylene-ethylene copolymerized portion is 3
-5 dl / g, preferably 4-5 dl / g. When the intrinsic viscosity [η] is less than 3 dl / g, the effect of improving the impact resistance is insufficient, while when it exceeds 5 dl / g, the rigidity and the impact resistance decrease.

The MFR of such a propylene-ethylene block copolymer is 25 to 40 g / 10 minutes, preferably 30 to 40 g / 10 minutes. MFR value is 25g / 1
If it is less than 0 minutes, the moldability of the obtained composition, particularly injection moldability, will be lowered, and if it exceeds 40 g / 10 minutes, the mechanical strength will be lowered.

(B) Ethylene-Propylene Copolymer Rubber and Ethylene-Butene Copolymer Rubber The above-mentioned propylene-ethylene block copolymer may be used alone, but ethylene-propylene copolymer rubber and ethylene-butene copolymer rubber may be used alone. When used in combination with the copolymer rubber, impact resistance and the like can be further improved. The MFR of ethylene-propylene copolymer rubber (EPR) is 1
-20 g / 10 minutes, preferably 3-20 g / 10 minutes. If the MFR is less than 1 g / 10 minutes, the moldability is lowered, while if it exceeds 20 g / 10 minutes, the mechanical strength is lowered. Further, from the viewpoint of handling property, productivity, etc., the content of ethylene is 50 to 90 mol%, the content of propylene is 50.
-10 mol% is preferable, and the content of ethylene is 60.
It is more preferable that the content is ˜85 mol%, and the propylene content is 40˜15 mol%.

Ethylene-butene copolymer rubber (EBR)
Has an MFR of 1 to 30 g / 10 minutes, preferably 5 to 20
g / 10 minutes. When the MFR is less than 1 g / 10 minutes, the moldability is lowered, while when it exceeds 30 g / 10 minutes, the mechanical strength is lowered. From the viewpoints of handling properties, productivity, etc., the ethylene content is 70 to 90 mol%, butene-
The content of 1 is preferably 30 to 10 mol%, the content of ethylene is 80 to 90 mol%, the content of butene-1 is 20.
It is more preferably from 10 to 10 mol%. In addition, ethylene-
The butene copolymer rubber may contain, in addition to ethylene and butene-1, a small amount of other α-olefins such as hexene-1 and octene-1, diene compounds such as ethylidene norbornene and dicyclopentadiene.

(C) Talc The talc used in the present invention has an average particle size of 5 μm or less, preferably 1 to 5 μm, as measured by a laser diffraction / scattering method. If the average particle size of talc exceeds 5 μm, the specific surface area cannot be sufficiently increased, and the rigidity and impact resistance of the composition decrease.

From the viewpoint of improving mechanical strength, heat resistance and weather resistance, it is preferable to use talc surface-treated with modified silicone. As the modified silicone for treating talc, a modified silicone obtained by adding a silazane compound to an organopolysiloxane (typically, polydimethylsiloxane etc.) is preferable.
Examples of the silazane compound include silazane, disilazane,
Examples thereof include trisilazane and hexacyclosilazane. The addition amount of the above-mentioned silazane compound is 0.1 to 5% by weight, especially 1 to 5% based on 100% by weight of the whole modified silicone.
It is preferably 3% by weight.

The surface treatment of talc with the above modified silicone is carried out by blending 0.1 to 5 parts by weight, especially 0.2 to 1 part by weight of modified silicone with 100 parts by weight of talc and mechanically using a Henschel mixer or the like. It can be performed by mixing.

Although the reason why such an effect is obtained is not always clear, the surface of talc is treated with a modified silicone such as a silazane compound to obtain a polypropylene resin component (propylene-ethylene block copolymer alone or ethylene with ethylene block copolymer). It is considered that this is because the dispersibility of talc in the propylene copolymer rubber and the ethylene-butene copolymer rubber) becomes good, and the adsorbability of various additives to talc is significantly reduced.

(D) Antioxidant The phenolic antioxidant used in the present invention acts as a heat resistance stabilizer. As the phenolic antioxidant, pentaerythrityl-tetrakis- [methylene-3- (3,3
5-di-t-butyl-4-hydroxyphenyl) propionate], 3,9-bis {2- [3- (3-t-butyl-4-hydroxy-5-methylphenyl) propionyloxy] -1,1 -Dimethylethyl} -2,4,8,
10-Tetraoxapyro [5,5] undecane, 1,
3,5-tris (2,6-dimethyl-3-hydroxy-
4-t-butylbenzyl) isocyanurate, 1,3
5-tris (3,5-di-t-butyl-4-hydroxybenzyl) -2,4,6-trimethylbenzene, 1,
3,5-tris (3,5-di-t-butyl-4-hydroxybenzyl) isocyanurate, bis (3,5-di-)
Examples include calcium t-butyl-4-hydroxybenzylphosphonate) and the like. Among commercially available phenolic antioxidants, the trade name is "Irganox 1010"
And "Irganox 3114" (Ciba Geigy)
Etc. are preferred. These may be used alone or in combination.

(E) Hindered amine UV stabilizer The hindered amine UV stabilizer used in the present invention is
Those having a molecular weight of 700 to 10,000 are preferable.
The more preferable range of the molecular weight is 1,000 to 4,000. When the molecular weight of the hindered amine light stabilizer is less than 700, part of the hindered amine light stabilizer volatilizes to cause clouding on the inner surface of the glass, while when it exceeds 10,000, the light resistance decreases. Examples of such hindered amine light stabilizers include dimethyl succinate 1- (2-hydroxyethyl) -4-hydroxy-2,2,6,6-tetramethylpiperidine polycondensate, poly {[(6- ( 1, 1,
3,3-Tetramethylbutyl) amino-1,3,5-triazine-2,4-diyl] [2- (2,2,6,6-
Tetramethyl-4-piperidyl) imino] hexamethylene [4- (2,2,6,6-tetramethyl-4-piperidyl) imino]}, N, N'-bis (3-aminopropyl) ethylenediamine-2, 4-bis [N-butyl-N
-(1,2,2,6,6-pentamethyl-4-piperidyl) amino] -6-chloro-1,3,5 triazine condensate and the like can be mentioned. Among commercially available hindered amine-based light stabilizers, trade names “Tinuvin 622LD” and “C
himassorb944FL "," Chimasso
rb944LD "," Chimassorb 119F
L "(manufactured by Ciba Geigy) and the like are preferable.

[2] Mixing ratio The mixing ratio of the polypropylene resin component is propylene-
The ethylene block copolymer is 75 to 95% by weight, preferably 83 to 91% by weight, and the ethylene-propylene copolymer rubber and the ethylene-butene copolymer rubber are 0 to 1%.
0% by weight, preferably 1 to 6% by weight, 5% talc
-15% by weight, preferably 9-11% by weight. The weight ratio of the ethylene-propylene copolymer rubber and the ethylene-butene copolymer rubber is preferably 0.5-2. Regarding the additive, a phenolic antioxidant is 0.05 to 1 part by weight, preferably 0.1 to 0.5 part by weight, based on 100 parts by weight of the polypropylene resin component, and a hindered amine ultraviolet stabilizer. Is 0.1 to 1 part by weight, preferably 0.2 to 0.5 part by weight.

If the blending amount of the propylene-ethylene block copolymer is less than 75% by weight, the ductility and hardness are low, while if it exceeds 95% by weight, the impact resistance is lowered. Even if the blending amount of the ethylene-propylene copolymer rubber and the ethylene-butene copolymer rubber exceeds 10% by weight, the effect of improving moldability and heat resistance commensurate with that is not seen. If the content of talc is less than 5% by weight, the rigidity and heat resistance are low, while if it exceeds 15% by weight, the impact resistance decreases. If the weight ratio of the ethylene-propylene copolymer rubber and the ethylene-butene copolymer rubber is outside the above range, the balance of ductility, impact resistance and cost is deteriorated, which is not preferable. Further, the compounding amount of the phenolic antioxidant is 0.
If it is less than 05 parts by weight, the heat resistance is low, while if it exceeds 1 part by weight, the volatile components therein cause clouding on the inner surface of the glass, which is not preferable. Further, if the content of the hindered amine-based ultraviolet stabilizer is less than 0.1 part by weight, the light resistance is low, while if it exceeds 1 part by weight, the volatile component therein causes fogging on the inner surface of the glass, which is not preferable.

[3] Other Components In the polypropylene composition of the present invention, other additives such as a nucleating agent, a flame retardant, a plasticizer, an antistatic agent, and a release agent may be added for the purpose of modifying the polypropylene composition. , A foaming agent, a coloring agent, a pigment and the like can be added. When a pigment is used, it is preferable to use polyethylene wax as a dispersant.

[4] Method for Producing Polypropylene-Based Composition The polypropylene-based composition of the present invention is prepared by mixing the above components using a Henschel mixer, a super mixer, a ribbon blender, etc., and then using a single-screw extruder, a twin-screw extruder, a Banbury mixer. It can be obtained by melt-kneading in a temperature range of 180 to 230 ° C. with a kneader. Further, a masterbatch in which additives such as talc, an antioxidant and an ultraviolet stabilizer are added at a high concentration may be prepared in advance, and this may be blended with the polypropylene resin component.

[0028]

The present invention will be described in more detail with reference to the following Examples and Comparative Examples, but the present invention is not limited thereto. Examples 1 and 2, Comparative Examples 1 to 4 1. Raw material (a) Propylene-ethylene block copolymer (BPP) -MFR (g / 10min): 34-Propylene-ethylene copolymer part ratio (wt%): 11 Ethylene content (wt%): 42 Intrinsic viscosity (dl / g): 5 ・ Homopolypropylene part ratio (weight%): 89 Heat of fusion (cal / g) Measured value (△ H _m ) ^* : 27 Calculated value (calculated by 24.5 + 1.583 log MFR): 26.9 *) DSC (Perkin) Measured by Elma (heating rate: 20 ° C / min). (b) Ethylene-propylene copolymer rubber and ethylene-butene copolymer rubber EPR: Ethylene-propylene copolymer rubber (EP02P, manufactured by Nippon Synthetic Rubber Co., Ltd.) MFR (g / 10min): 3.2, ethylene content = 74 wt% EBR: Ethylene-butene copolymer rubber (EBM1201P, manufactured by Nippon Synthetic Rubber Co., Ltd.) MFR (g / 10min): 30, ethylene content = 83 wt% (c) Talc (LMS300, Fuji Talc Industry Co., Ltd.) (Manufactured by Co., Ltd.) Average particle size (μm): 3.8 μm (measured by laser diffraction scattering method) (d) Phenolic antioxidant IR1010: Irganox 1010, manufactured by Ciba Geigy IR3114: Irganox 3114, manufactured by Ciba Geigy (e) Hindered amine UV stabilizer Chim-944: poly {[(6- (1,1,3,3-tetramethylbutyl) amino-1,3,5-triazine-2,4-diyl] [
2- (2,2,6,6-Tetramethyl-4-piperidyl) imino] hexamethylene [4- (2,2,6,6-tetramethyl-
4-Piperidyl) imino]} (Chimassorb944, Ciba
Geigy product, molecular weight 2500 or more) T-770: screw (2,2,6,6)
-Tetramethyl-4-piperidyl) sebacate (Tinuvi
n770, manufactured by Ciba-Geigy, molecular weight 480.7) (f) Other additives MARK2112: Phosphorus antioxidant (manufactured by Asahi Denka Co., Ltd.) DSTDP: Sulfur antioxidant (distearyl-3,3'-thio) Dipropionate, manufactured by Ciba Geigy) S-20: Stearic acid (manufactured by NOF Corporation)

2. Kneading and molding method The above raw materials were blended in the ratios shown in Table 1, dry-blended using a super mixer, and then 200 rpm at 200 ° C. with a twin-screw extruder (PCM-45 manufactured by Ikegai Corp.).
The mixture was melt-kneaded at a screw rotation speed of m and extruded to obtain pellets. The obtained pellets were injection-molded by an injection molding machine at a resin temperature of 210 ° C., an injection pressure of 1800 kg / cm ² and a mold temperature of 50 ° C. to prepare test pieces.

3. Physical property measurement Physical property measurement of each test piece was performed by the following methods. The results are shown in Table 1 below. (1) MFR (g / 10 minutes): Measured according to ASTM D1238 at 230 ° C and a load of 2.16 kg. (2) Tensile strength (kg / cm ² ): Measured at room temperature according to ASTM D638. (3) Tensile elongation at break (%): Measured at room temperature according to ASTM D638. (4) Flexural modulus (kg / cm ² ): Measured at room temperature according to ASTM D790. (5) Flexural strength (kg / cm ² ): Measured at room temperature according to ASTM D790. (6) Izod impact strength (kgcm / cm): Using ASTM D256, a 3.2 mm thick test piece was used, and it was notched at 23 ° C and
It was measured at -30 ° C. (7) Heat distortion temperature (℃): 18.6kg / cm ^{2 according} to ASTM D648
The pressure was measured. (8) Rockwell hardness (scale R): Measured by ASTM D785. (9) Brittleness temperature (° C): Measured by ASTM D746. (10) Glass haze (%): 500 ml of 25 × 50 × 2 mm test piece
Place it in a pressure-resistant bottle for measuring cloud point, and seal it with a glass plate (47 × 47 mm in size, 3 mm in thickness, which also serves as a lid, with a haze of 0.5% or less). Dip it in oil up to 2/3 the height of this pressure bottle, and
After heating at ℃ for 20 hours, the haze value of the glass plate is
Measured by TM E308. (11) Weather resistance: Accelerated test (black panel temperature 83 using Sunshine Carbon Arc (Suga Test Co., Ltd.))
(° C, 1000 hours), and the surface appearance was observed with a microscope. ○: No cracks △: Slight cracks occurred ×: Cracks occurred

Table 1 Example 1 Example 2 Comparative Example 1 Composition polypropylene resin component (% by weight) (a) BPP 84 84 84 (b) EPR 3 3 3 EBR 3 3 3 (c) Talc 10 10 10 Additive (Parts by weight) (d) Antioxidant IR1010 0.2 1.0 0.1 IR3114 0.2 1.0 ─ (e) UV stabilizer Chim-944 0.2 1.0 ─ T-770 ─ ─ 0.2 (f) Other MARK2112 ─ ─ 0.1 DSTDP ─ ─ ─ S -20 ─ ─ 0.3 Characteristic of composition MFR (g / 10min) 29 29 32 Tensile strength (kg / cm ² ) 270 280 270 Tensile elongation at break (%) 120 100 130 Flexural modulus (kg / cm ² ) 20600 21000 20400 Bending strength (kg / cm ² ) 390 390 380 Izod impact strength ⁽¹⁾ 23 ℃ 7.3 7.4 7.5 -30 ℃ 2.3 2.3 2.4 Heat distortion temperature (℃) 71 72 71 Rockwell hardness (R) 89 90 89 Embrittlement Temperature (℃) 14.5 14.5 14.0 Glass haze (%) 1.5 3.5 35.0 Weather resistance ○ ○ ○ Note (1): Unit: kg ・ cm / cm

Table 1 (continued) Comparative Example 2 Comparative Example 3 Comparative Example 4 Composition polypropylene resin component (% by weight) (a) BPP 84 84 84 (b) EPR 3 3 3 EBR 3 3 3 (c) Talc 10 10 10 Additives (parts by weight) (d) Antioxidant IR1010 0.1 0.1 0.2 IR3114 ─ ─ 0.2 (e) UV stabilizer Chim-944 ─ ─ ─ T-770 0.2 0.2 ─ (f) Others MARK2112 0.1 ─ ─ DSTDP ─ 0.1 0.05 S-20 ─ ─ ─ Properties of composition MFR (g / 10min) 29 33 30 Tensile strength (kg / cm ² ) 270 260 270 Tensile elongation at break (%) 120 140 120 Flexural modulus (kg / cm) ² ) 20600 20200 20100 Bending strength (kg / cm ² ) 380 370 390 Izod impact strength ⁽¹⁾ 23 ℃ 7.1 7.7 7.3 -30 ℃ 2.2 2.5 2.3 Heat distortion temperature (℃) 70 70 71 Rockwell hardness (R) 88 87 89 Brittleness temperature (℃) 14.5 13.5 14.5 Glass haze (%) 12.3 25.4 0.4 Weather resistance ○ ○ ×

As is clear from Table 1, Examples 1 and 2
The polypropylene-based composition is excellent in mechanical strength such as impact resistance, hardness, rigidity, moldability, heat stability, weather resistance, etc., and has low glass haze and prevents fogging on the inner surface of the glass. be able to. On the other hand, the polypropylene-based compositions of Comparative Examples 1 to 3 have high glass haze and low effect of preventing fogging on the inner surface of the glass, and the polypropylene-based compositions of Comparative Example 4 have poor weather resistance.

As described in detail above, the polypropylene composition of the present invention comprises: (a) a propylene-ethylene block copolymer having a melt flow rate (MFR) of 25 to 40 g / 10 minutes; ) MFR 1 to 20 g / 10 min ethylene-propylene copolymer rubber, and MFR 1 to 3
0 g / 10 min ethylene-butene copolymer rubber, (c)
The propylene-ethylene block copolymer (a) contains talc having an average particle size of 5 μm or less,
3-20 wt% propylene-ethylene copolymerized portion per weight% (the intrinsic viscosity is 3-5 dl / g, the ethylene content of the copolymerized portion is 30-50 wt%), the heat of fusion and MFR. However, since it is composed of a polypropylene resin component containing a propylene homopolymer portion satisfying a certain relationship, (d) a phenolic antioxidant, and (e) a hindered amine ultraviolet stabilizer, impact resistance, hardness In addition to being excellent in mechanical strength such as rigidity, moldability, and heat stability, it is possible to prevent fogging on the inner surface of the glass.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location C08K 5/17 C08K 5/17 C08L 23/16 LCY C08L 23/16 LCY (72) Inventor Kunio Iwanami 3-1-1 Chidori-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa Tonen Chemical Co., Ltd. Technology Development Center (72) Inventor Akira Kobayashi 3-1-1 Chidori-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa Tonen Kagaku Co., Ltd. Technical Development Center (72) Inventor Yuji Fujita 3-1-1 Chidori-cho, Kawasaki-ku, Kawasaki, Kanagawa Tonen Kagaku Co., Ltd. Technical Development Center (72) Inventor Shinya Kawamura 1-cho, Toyota-cho, Aichi Prefecture Toyota Automobile Co., Ltd. (72) Inventor Takao Nomura 1 Toyota-cho, Toyota-shi, Aichi Toyota Motor Corporation (72) Inventor Takesumi Nishio 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Automobile Co., Ltd.

Claims (2)

[Claims] 1. A propylene-ethylene block copolymer having a melt flow rate (MFR) of 25 to 40 g / 10 minutes (a) of 75 to 95% by weight, and (b) a MFR of 1 to 20.
g / 10 min ethylene-propylene copolymer rubber, and MFR 1-30 g / 10 min ethylene-butene copolymer rubber 0-10 wt% and (c) 5-15 wt% talc having an average particle size of 5 μm or less. The propylene-ethylene block copolymer (a) contains 3 to 20% by weight per 100% by weight of the propylene-ethylene copolymerized portion (the intrinsic viscosity is 3 to 5 dl / g, and the copolymerized portion is Has an ethylene content of 30 to 50% by weight, and the heat of fusion (△
H _m ) and MFR are ΔH _m ≧ 24.5 + 1.583 l
100 parts by weight of a polypropylene resin component containing a propylene homopolymer portion satisfying the relational expression ogMFR, (d) 0.05 to 1 part by weight of a phenolic antioxidant, and (e) a specific hindered amine ultraviolet stabilizer. Agent 0.
A polypropylene composition comprising 1 to 1 part by weight. 2. The polypropylene-based composition according to claim 1, wherein the ethylene-propylene copolymer rubber is:
The weight ratio with the ethylene-butene copolymer rubber is 0.5 to 2
The polypropylene-based composition is characterized in that