JP3401530B2 - Polypropylene resin composition - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention has high rigidity, high heat resistance,
The present invention relates to a polypropylene resin composition having excellent impact resistance.

[0002]

2. Description of the Related Art Polypropylene (hereinafter referred to as "PP") is inexpensive, and isotactic crystalline polypropylene is excellent in rigidity, surface gloss and heat resistance.
However, under normal molding conditions, the degree of crystallinity does not rise sufficiently (70% or less), so it cannot be said that rigidity and heat resistance are sufficient as an alternative to engineering plastics. Further, PP has a drawback that it is essentially inferior in impact resistance at low temperatures necessary for industrial materials and the like.

As a method for improving impact resistance in order to improve this, a method of adding an amorphous rubber-like substance to PP by blending or multistage polymerization is widely used. However, such modification has a drawback that the original characteristics of PP, such as rigidity, surface hardness, and heat resistance, are reduced. Many attempts have been made to use fillers such as talc and glass fiber for the purpose of improving the lowered rigidity and heat resistance of the PP material containing rubber, but the addition of these increases the density of the material and In addition to the large weight of a molded product of a size, the addition amount as a filler is quantitatively limited due to deterioration of the appearance and the like, and it has been difficult to obtain a satisfactory material.

As another method for improving the rigidity and heat resistance of a PP material containing rubber, there is a means for increasing the MFR of PP (to lower the molecular weight). The increase in MFR of PP is also effective from the viewpoint of improving moldability. However, an increase in MFR inevitably causes a decrease in the impact resistance of the material.
As a means for improving the rigidity and heat resistance without changing the MFR, it is most common to increase the stereoregularity of polypropylene, and there is a method of widening the molecular weight distribution together with it. However, when the molecular weight distribution is widened, there is a problem that impact resistance (particularly surface impact resistance) is lowered.

Therefore, in order to improve the impact resistance while maintaining the rigidity and heat resistance of the PP material containing the rubber without causing other troubles, it is possible to develop the impact resistance with the least amount of rubber. Will be needed. Known means for achieving this include reinforcing the interface between the matrix PP and rubber and finely dispersing the rubber. As a reinforcement of the interface between PP and rubber, a method using a graft reaction is also proposed (Lohse et. Al., Macromolec).
ules, 24, 561 (1991)),
Satisfactory results have not been obtained due to generation of gel, decrease in MFR, and the like. Fine dispersion has been proposed as another means for improving impact resistance with a smaller amount of rubber. Wu
(Wu, Polymer, 26, 1855 (198
According to 5)), in a system in which rubber (EPDM) is dispersed in nylon, impact resistance is dominated by the distance between rubber dispersed particles, and impact resistance is improved by reducing the distance between particle walls. It has been shown that this also holds true for the PP / ethylene propylene rubber (EPR) system (Akiyo
shi et. al. , Polymer Prepri
nts, 39, 3699 (1990)). In order to reduce the distance between the particle walls with the same amount of rubber, it is necessary to finely disperse the rubber.

In this case, in order to achieve fine dispersion of the rubber, it is desirable that the melt viscosity of PP and the rubber during kneading in the extruder are close to each other. On the other hand, the molecular weight of the rubber is preferably high from the viewpoint of maintaining impact resistance, but in this case the melt viscosity becomes high.
It should be noted that increasing the MFR of PP (reducing the molecular weight) to maintain rigidity and heat resistance means that the melt viscosity of the rubber relative to the melt viscosity of PP is considerably increased, resulting in poor dispersion. In addition, when the molecular weight distribution of PP is wide, the rigidity and heat resistance are improved, but the melt viscosity in the high shear region in the extruder becomes small, the melt viscosity difference with rubber becomes large, and the dispersion deteriorates. Furthermore, in injection molding, if the molecular weight distribution of PP is wide, the orientation layer develops,
No suitable means has been proposed for obtaining a low temperature impact resistant PP resin composition which is excellent in rigidity and heat resistance such that orientation cracking is likely to occur and surface impact is particularly deteriorated.

[0007]

SUMMARY OF THE INVENTION The present invention improves the impact resistance of PP at low temperatures and prevents deterioration of physical properties such as rigidity and heat resistance due to compounding of a rubber component, and provides PP with high rigidity and high heat resistance. The purpose is to develop a polypropylene-based polymer that has excellent impact resistance while maintaining

[0008]

DISCLOSURE OF THE INVENTION The invention relates to (A) propylene chain isotactic pentad fraction (mmmm
%) Is 99.0 or more, and the Q value (Mw obtained from GPC)
/ Mn) is a relational expression (1) 9-0.58xlogMFR (g / 10min)>Q> 6.5-0.58xlogMFR (g / 10min) ... (1) (However, MFR is , JIS K7210, Table 1, Condition 14
Is the melt flow rate. 4) satisfying the above conditions, 49-89 wt% of polypropylene, (B) ethylene-propylene rubber 10-50 wt%, and (C) a copolymer containing a part consisting of α-olefinylene having 4 or more carbon atoms as a dispersion promoter and ethylene. The above object was achieved by developing a polypropylene resin composition containing 10 wt%. In the present invention, PP used as the component (A) is mainly composed of isotactic polypropylene (abbreviated as homo PP) or propylene, and contains a small amount (usually 10 parts by weight or less) of ethylene or butene.
Although it is a random copolymer of α-olefin such as 1, homo-PP is preferable from the viewpoint of rigidity and heat resistance.

The present invention uses PP as component (A)
The isotactic pentad fraction (mmmm%) of the propylene chain of is 99.0 or more, and the Q value (Mw / Mn) obtained from GPC (gel permeation chromatography) is the following relational expression (1) 9-0. 0.58 × log MFR (g / 10 minutes)>Q> 6.5-0.58 × log MFR (g / 10 minutes) ... If the isotactic pentad fraction is less than 99.0, the rigidity and heat resistance will be insufficient. Further, when the Q value is the above or less, rigidity and heat resistance are lowered, and when the Q value is the above or more, the orientation layer is developed, and as a result, the impact resistance strength (particularly surface impact) is lowered. The catalyst system which gives PP necessary for the present invention includes metallocene and titanium-based (magnesium-supported-TiCl ₃
Any of these) may be used, but those producing high stereoregularity are preferred. Moreover, you may use what adjusted molecular weight distribution by blending, multistage polymerization, etc. as needed.

The ethylene-propylene rubber as the component (B) used in the present invention is a copolymer of ethylene and propylene and has an ethylene content of 40 to 90 wt%,
Preferably 50-80 wt%, MFR 0.1-10 g
/ 10 minutes, preferably 0.5 to 3 g / 10 minutes. At the time of producing the ethylene-propylene rubber of the present invention, polymerization may be carried out using any catalyst system of titanium series, vanadium series and metallocene series.

As the dispersion accelerator of the component (C) for achieving the object of the present invention, a copolymer having a portion composed of ethylene and an α-olefin having 4 or more carbon atoms can be used.
The part composed of ethylene and the α-olefin having 4 or more carbon atoms has compatibility with both the component (A) PP and the component (B) ethylene-propylene rubber, and as a result, the copolymer having this part is dispersed. By using it as a promoter,
When a polypropylene resin having a specific Q value (slightly larger than that normally obtained with a magnesium-supported titanium-based catalyst) used in the present invention is used, ethylene-propylene rubber is finely dispersed, and PP and ethylene-propylene rubber are dispersed. Interface reinforcement is achieved, and the purpose of improving impact resistance is achieved while maintaining high rigidity and high heat resistance properties. As the dispersion promoter of the above component (C), specifically, a random copolymer such as an ethylene-butene copolymer, an ethylene-isoprene copolymer, an ethylene-hexene copolymer, an ethylene-octene copolymer, Examples thereof include a block copolymer having an ethylene block and an ethylene-butene block, a copolymer having a styrene block and an ethylene-butene block, and a copolymer having an MFR of about 0.5 to 30 g / 10 minutes. In particular, in order to maintain the rigidity and heat resistance of the polypropylene resin composition, it is desirable to use a block copolymer. If the blending amount of the dispersion accelerator is less than 2 wt% of the resin composition, the effect is not sufficiently exhibited. On the other hand, if it exceeds 10 wt%, the heat resistance of the resin composition is lowered. It is preferably 3 to 8%. When the blending method is used, any dispersion accelerator can be added by kneading in an extruder.

The blending method for obtaining the polypropylene resin composition of the present invention is not particularly limited. When the blending method is used, either a single-screw or twin-screw extruder may be used. It is preferable to use a twin-screw extruder with sufficient kneading. As the PP of the component (A) of the present invention, the same additives such as a heat / oxidation stabilizer, a nucleating agent, a light stabilizer, an antistatic agent, and a lubricant which are blended with a normal PP can be used if necessary. Further, it may be partially modified with a radical initiator such as a peroxide or a modifier such as an unsaturated carboxylic acid within a range satisfying the relational expression (1). Further, various polypropylene or polybutene in the polypropylene resin composition of the present invention,
An olefin-based copolymer such as an ethylene-butene copolymer,
It is also possible to mix and use an inorganic filler such as talc, calcium carbonate, lithium carbonate, mica or glass fiber. Particularly, in order to improve rigidity and heat resistance, it is desirable to use a nucleating agent and a filler.

[0013]

The rubber component is blended in order to improve the impact resistance of the PP resin, but when blended, there is a problem that the rigidity and heat resistance are lowered. The present invention is a matrix PP
We succeeded in reducing the compounding amount of the rubber component by reinforcing the rubber interface and uniformly dispersing the rubber. In the present invention, the isotactic pentad fraction (mmm
m%) is 99.0 or more, and the Q value (Mw /
By using a PP resin whose Mn) satisfies the relational expression (1) and adding ethylene-propylene rubber and a dispersion accelerator to the PP resin, the dispersion accelerator exists at the interface between PP and the ethylene-propylene rubber, and It is presumed that fine dispersion is achieved as a result of having compatibility with and reducing the interfacial tension between the two. Therefore, the dispersion accelerator has a role of reducing the interfacial tension and achieving fine dispersion, and at the same time, reinforcing the interface between PP and ethylene-propylene rubber. As a result, the impact resistance is maintained while maintaining high rigidity and high heat resistance. It is considered that a polypropylene resin composition having excellent properties was obtained.

[0014]

【Example】

(Examples) Examples of the present invention will be shown below, but the present invention is not limited thereto. [Measurement method] Various physical properties were measured by the following methods. (1) Isotactic pentad fraction (mmmm
%) Was measured using the data obtained by ¹³ C-NMR. Za
mbelli et al.'s method (Macromolecule
s, 6 , 925 (1973)). (2) Molecular weight distribution measurement Shodex was added to a Waters 150C type GPC device.
Two AT-80M / S columns were connected in series and used. 1,2,4-trichlorobenzene containing 0.01% of BHT was used as a solvent, the sample was dissolved, and then filtered with a 0.5 μm sintered metal filter, and measured at 140 ° C. The obtained chromatogram was calibrated using standard polystyrene. The molecular weight was converted to polypropylene using the universal method. The weight fraction of each molecular weight was determined from the relationship between the obtained molecular weight and the elution amount. (3) MFR JIS K-7210 Table 1, condition 14 (test temperature 23
It was measured at 0 ° C. and a test load of 2.16 kgf). (4) Izod impact strength Tested according to ASTM D256 using a notched test piece. (5) Surface impact strength When a head with a weight attached thereto was dropped from a certain height on an injection-molded flat plate having a thickness of 2 mm, half of the weight was evaluated. (6) Flexural modulus Measured according to JIS K-7207. (7) Heat distortion temperature (HDT) Measured according to JIS K-7207.

[Preparation of Polymer] (Preparation of Solid Catalyst Component) (Step 1) 47.6 g (50) of anhydrous magnesium chloride under a nitrogen atmosphere.
0 mmol), 259 ml of decane and 234 ml (1.5 mol) of 2-ethylhexyl alcohol at 130 ° C.
After heating the mixture for 2 hours to form a homogeneous solution, 11.1 g (75 mmol) of phthalic anhydride was added to this solution, and the mixture was stirred and mixed at 130 ° C. for 1 hour to dissolve the phthalic anhydride in the solution. Let After cooling the obtained homogeneous solution to room temperature, the whole amount was dropped into 2.0 liters (18 mol) of titanium tetrachloride kept at -20 ° C over 1 hour. After the dropwise addition was completed, the temperature of the mixed solution was raised over 4 hours, and when reaching 110 ° C, 26.8 ml (125 mmol) of diisobutyl phthalate was added, and the mixture was reacted with stirring at 110 ° C for 2 hours. After completion of the reaction, a solid component was collected by filtration under heating, and titanium tetrachloride (2.0 ml) was added to the reaction product.
After adding liter (18 mol) and suspending, 110 ° C
And reacted for 2 hours. After completion of the reaction, the solid component was collected again by hot filtration and washed with 2.0 liters of decane at 110 ° C. 7 times and 2.0 liters of hexane at room temperature 3 times.

(TiCl ₄ [C ₆ H ₄ (COO-i-C
₄ H ₉ ) ₂ ]) (Step 2) Diisobutyl phthalate (27.8 g (1) was added to 1.0 liter of hexane containing 19 g (100 mmol) of titanium tetrachloride.
(00 mmol) was added dropwise for about 30 minutes while maintaining 0 ° C. After completion of the dropping, the temperature was raised to 40 ° C. and the reaction was performed for 30 minutes.
After the reaction was completed, the solid component was collected and mixed with 500 ml of hexane.
It was washed twice to obtain the desired product.

(TiCl ₄ [C ₆ H ₄ (COO-i-C
₄ H ₉ ) ₂ ]) (Step 3) 40 g of the solid catalyst obtained in Step 1 was added to 600 ml of toluene.
TiCl ₄ [C ₆ H obtained in Step 2 at 25 ° C.
_{4 (COO-i-C 4} H 9) 2] 10.3g (22mm
ol) for 1 hour. After completion of the reaction, 200 ml (1.8 mol) of titanium tetrachloride was added, and the mixture was reacted at 110 ° C for 2 hours. After completion of the reaction, a solid component was collected by hot filtration, and then the reaction product was added to 600 ml of toluene and 200 ml (1.8 mol) of titanium tetrachloride and suspended, and then reacted at 110 ° C. for 2 hours. After the reaction was completed, the solid component was collected by hot filtration again, and the toluene at 110 ° C. 1.
7 times with 0 liter, 3 times with 1.0 liter of hexane at room temperature
Washed twice.

(Preliminary polymerization catalyst component) In a nitrogen atmosphere, in an autoclave having an internal volume of 3 liters, 500 ml of n-heptane and 6.0 g (0.0
53 mol), t-butyltrimethoxysilane 3.1 g
(0.017 mol) and 100 g of the solid catalyst component obtained in step 3 were added, and the mixture was stirred at a temperature range of 0 to 5 ° C for 5 minutes. Next, propylene was fed into the autoclave so that 10 g of propylene was polymerized per 1 g of the solid component, and prepolymerized in the temperature range of 0 to 5 ° C for 1 hour. The obtained prepolymerization catalyst was washed 3 times with 500 ml of n-heptane and used for the following polymerization.

Component (A): Preparation of PP (Low MFR component-1) 2.0 g of prepolymerized catalyst component prepared by the above method using an autoclave with a stirrer and an internal volume of 60 liters in a nitrogen atmosphere, triethyl 11.4 g (100 mmol) of aluminum, 5.9 g (33 mmol) of t-butyltrimethoxysilane were added, and then 18 kg of propylene and the MFR of the polymer were 2.0.
Hydrogen was supplied so as to be g / 10 minutes, and polymerization was performed at 70 ° C. for 30 minutes. Unreacted gas is purged to target PP
Got The obtained PP has an MFR of 3.9 g / 10 minutes, Q
= 5.5, the isotactic pentad fraction is 99.
It was 4%.

(Low MFR component-2) In a nitrogen atmosphere, an autoclave with an internal volume of 60 liters equipped with a stirrer was used, and 2.0 g of the prepolymerization catalyst component prepared by the above method, 11.4 g (100 mmol) of triethylaluminum, t
-Butyltrimethoxysilane 5.9 g (33 mmol)
, Then 18 kg of propylene and M of polymer
Supply hydrogen so that FR becomes 1.0g / 10min, and
Polymerization was carried out at 0 ° C. for 30 minutes. Unreacted gas was purged to obtain the desired PP. The obtained PP has an MFR of 1.8 g.
/ 10 min, Q = 5.5, and isotactic pentad fraction was 99.4%.

(High MFR component) Under nitrogen atmosphere, internal volume 6
Using a 0 liter autoclave equipped with a stirrer, 2.0 g of the prepolymerization catalyst component prepared by the above method, 11.4 g (100 mmol) of triethylaluminum, and 5.9 g (33 mmol) of t-butyltrimethoxysilane were added, and 18 kg of propylene and MFR of polymer
Is supplied at a temperature of 70 g
Polymerization was carried out for 30 minutes. Unreacted gas was purged to obtain the desired PP. The obtained PP has an MFR of 250 g / 1
At 0 minutes, Q = 4.0, the isotactic pentad fraction was 99.4%.

Component (B): Preparation of ethylene-propylene rubber 3 liters of dehydrated toluene was charged in a 6 liter autoclave, and a toluene solution of methylalumoxane (Molecular weight 1026) manufactured by Tosoh Akzo Co., Ltd. was used at 380 A1 atoms.
mmol, ethylenebis (indenyl) zirconium chloride (Et (Ind) ₂ ZrCl ₂ ) 1.9 × 1
30 ml of a 0 ^-2 mmol / ml toluene solution was added, and the mixture was stirred at room temperature for 10 minutes. After cooling the temperature of the autoclave to 2 ° C., an ethylene / propylene (molar ratio 7/3) mixed gas was introduced into the autoclave using a mass flow meter, and polymerization was carried out at this temperature for 1 hour. After the polymerization, the content was put into a large amount of methanol-hydrochloric acid to separate the produced ethylene-propylene copolymer, and the solvent adhering to the copolymer was removed under reduced pressure at 50 ° C. Yield 150
It was g. The ethylene-propylene copolymer (EPR) thus obtained had an MFR of 1.8 g / 10 minutes and an ethylene content of 70 wt. %Met.

Example 1: 100 parts by weight of homo-PP containing 44 wt% of low MFR component-1 and 56 wt% of high MFR component as component (A), 0.08 part by weight of commercially available BHT and 0.05 parts of Irganox 1010. 2 parts by weight of a twin-screw extruder (K
It was melt-kneaded at 200 ° C. using TX-37). Obtained composition [polypropylene resin (PP-1), MF
R = 33.0 g / 10 min, Q = 5.7, (9-0.58
× logMFR = 8.1, 6.5-0.58logMF
R = 5.6), mmmm% = 99.4] 82.5 wt%
In addition, 12.5 wt% of the above EPR as the ethylene-propylene rubber of the component (B) and a hydrogenation butadiene block copolymer of MFR = 0.6 (manufactured by Nippon Synthetic Rubber Co., Ltd.) as the dispersion accelerator of the component (C). CEBC, Dynaron E
6100P) to 100 parts by weight of a resin composition consisting of 5 wt% sodium-2,2'-methylene-as a nucleating agent.
0.4 parts by weight of bis- (4,6-di-t-butylphenyl) phosphate (NA11 of Asahi Denka Co., Ltd.), 0.08 part by weight of BHT, which is a commercially available stabilizer, and 0.05 part by weight of Irganox 1010. Parts, and 0.1 part by weight of calcium stearate were added and melt-kneaded at 200 ° C. using a twin-screw extruder (KTX-37) to prepare a composition. A test piece was prepared using the obtained composition, and the physical properties were measured. The results are shown in Table 1.

Example 2: 100 parts by weight of homo PP containing 23 wt% of low MFR component-2 and 67 wt% of high MFR component as component (A), 0.08 part by weight of commercially available BHT and 0.05 parts of Irganox 1010. 2 parts by weight of a twin-screw extruder (K
It was melt-kneaded at 200 ° C. using TX-37). The composition obtained [polypropylene resin (PP-2), MF
R = 28.0 g / 10 minutes, Q = 6.9, (9-0.58
× logMFR = 8.2, 6.5-0.58logMF
R = 5.7), mmmm% = 99.4] 82.5 wt%
In addition, 12.5 wt% of the above EPR as the ethylene-propylene rubber of the component (B) and the hydrogenation-butadiene block copolymer used in Example 1 as the dispersion promoter of the component (C) (Nippon Synthetic Rubber Co., Ltd.). CEBC, manufactured by Dynaron E6100P) (5 wt%), based on 100 parts by weight of the resin composition, 0.4 parts by weight of the nucleating agent used in Example 1, 0.08 parts by weight of BHT, which is a commercially available stabilizer, and IRGA. 0.05 parts by weight of Knox 1010 and 0.1 parts by weight of calcium stearate were added, and a twin-screw extruder (KTX-3
7) was used and melt-kneaded at 200 ° C. to prepare a composition. A test piece was prepared using the obtained composition, and the physical properties were measured. The results are shown in Table 1.

Example 3: 75 wt% of the polypropylene resin (PP-1) used in Example 1 as the component (A), 20 wt% of the EPR used in Example 1 as the component (B), and implementation of the component (C). 0.4 part by weight of the nucleating agent used in Example 1, 0.08 part by weight of commercially available BHT, and 0 of Irganox 1010 were used per 100 parts by weight of the resin composition containing 5 wt% of the dispersion accelerator used in Example 1. 0.05 parts by weight and 0.1 parts by weight of calcium stearate were added and melt-kneaded at 200 ° C. using a twin-screw extruder (KTX-37).
A composition was made. A test piece was prepared using the obtained composition, and the physical properties were measured. The results are shown in Table 1.

Example 4: Dispersion of 55 wt% of polypropylene resin (PP-1) used in Example 1 as component (A), 20 wt% of EPR used in Example 1 as component (B), and component (C) Hydrogenated-styrene-butadiene block copolymer having MFR = 10 and styrene content of 20 wt% as an accelerator (SEBS manufactured by Asahi Kasei Corporation, Tuftec H105
2) With respect to 100 parts by weight of a resin composition consisting of 5% by weight and 20% by weight of Micelleton manufactured by Hayashi Kasei Co., Ltd., 0.08 parts by weight of commercially available BHT, 0.05 parts by weight of Irganox 1010, and 0 of calcium stearate. 1 part by weight was added, and the mixture was melt-kneaded at 200 ° C. using a twin-screw extruder (KTX-37) to prepare a composition. A test piece was prepared using the obtained composition, and the physical properties were measured. The results are shown in Table 2.

Example 5: 50 wt% of the polypropylene resin (PP-1) used in Example 1 as the component (A), 25 wt% of EPR used in the Example 1 as the component (B), and carried out as the component (C). 5 wt% of the dispersion accelerator used in Example 4
And 20 wt% of Hayashi Kasei's micelleton as a filler
% Of a resin composition consisting of 100% by weight, commercial 0.08 parts by weight of BHT, 0.05 parts by weight of Irganox 1010, and 0.1 parts by weight of calcium stearate were further added, and a twin-screw extruder (KTX- 37) using 200
Melt kneading was performed at 0 ° C. to prepare a composition. A test piece was prepared using the obtained composition, and the physical properties were measured. The results are shown in Table 2.
It was shown to.

Example 6: 50 wt% of the polypropylene resin (PP-1) used in Example 1 as the component (A), 20 wt% of EPR used in the Example 1 as the component (B), and carried out as the component (C). 5 wt% of the dispersion accelerator used in Example 4
And 25 wt% of Hayashi Kasei's micelleton as filler
% Of a resin composition consisting of 100% by weight, commercial 0.08 parts by weight of BHT, 0.05 parts by weight of Irganox 1010, and 0.1 parts by weight of calcium stearate were further added, and a twin-screw extruder (KTX- 37) using 200
Melt kneading was performed at 0 ° C. to prepare a composition. A test piece was prepared using the obtained composition, and the physical properties were measured. The results are shown in Table 2.
It was shown to.

Example 7: 50 wt% polypropylene resin (PP-2) used in Example 2 as component (A), 20 wt% EPR used in Example 1 as component (B), and component (C) 5 wt% of the dispersion accelerator used in Example 4
And 25 wt% of Hayashi Kasei's micelleton as filler
% Of a resin composition consisting of 100% by weight, commercial 0.08 parts by weight of BHT, 0.05 parts by weight of Irganox 1010, and 0.1 parts by weight of calcium stearate were further added, and a twin-screw extruder (KTX- 37) using 200
Melt kneading was performed at 0 ° C. to prepare a composition. A test piece was prepared using the obtained composition, and the physical properties were measured. The results are shown in Table 2.
It was shown to.

Example 8: 45 wt% of the polypropylene resin (PP-1) used in Example 1 as the component (A), 25 wt% of EPR used in the Example 1 as the component (B), and carried out as the component (C). 5 wt% of the dispersion accelerator used in Example 4
And 25 wt% of Hayashi Kasei's micelleton as filler
% Of a resin composition consisting of 100% by weight, commercial 0.08 parts by weight of BHT, 0.05 parts by weight of Irganox 1010, and 0.1 parts by weight of calcium stearate were further added, and a twin-screw extruder (KTX- 37) using 200
Melt kneading was performed at 0 ° C. to prepare a composition. A test piece was prepared using the obtained composition, and the physical properties were measured. The results are shown in Table 2.
It was shown to.

Example 9: 45 wt% of the polypropylene resin (PP-2) used in Example 2 as the component (A), 25 wt% of EPR used in Example 1 as the component (B), and carried out as the component (C). 5 wt% of the dispersion accelerator used in Example 4
And 25 wt% of Hayashi Kasei's micelleton as filler
% Of a resin composition consisting of 100% by weight, commercial 0.08 parts by weight of BHT, 0.05 parts by weight of Irganox 1010, and 0.1 parts by weight of calcium stearate were further added, and a twin-screw extruder (KTX- 37) using 200
Melt kneading was performed at 0 ° C. to prepare a composition. A test piece was prepared using the obtained composition, and the physical properties were measured. The results are shown in Table 2.
It was shown to.

(Comparative Example) [Preparation of Polymer] Preparation of Polypropylene Resin Component (A) (Medium MFR Component) Prepared in the same manner as in Examples using an autoclave equipped with a stirrer and having an internal volume of 60 liters under a nitrogen atmosphere. 2.0 g of the prepared prepolymerization catalyst component, triethylaluminum 11.
4 g (100 mmol) and t-butyltrimethoxysilane (5.9 g (33 mmol)) were added, then 18 kg of propylene and hydrogen were supplied so that the MFR of the polymer would be 30 g / 10 min, and polymerization was carried out at 70 ° C. for 30 minutes. .
Unreacted gas was purged to obtain the target polypropylene.
The obtained PP had an MFR of 31.4 g / 10 minutes and an isotactic pentad fraction of 99.4%. GP
The Q value obtained from C is 4.5 (9-0.58 x logMF
R = 8, 6.5-0.58 × log MFR = 5.6). (PP-3)

Comparative Example 1: Instead of the polypropylene resin (PP-1) used in the examples as the component (A), a medium MFR component (PP-3) 8 was used.
EP used in Example 1 as component (B) at 2.5 wt%
0.4 parts by weight of the nucleating agent used in Example 1, 0.08 parts by weight of commercially available BHT, and Irganox 1010 are used with respect to 100 parts by weight of a resin composition containing 17.5 wt% of R.
0.05 parts by weight and 0.1 parts by weight of calcium stearate were added, and the amount was adjusted to 20 using a twin-screw extruder (KTX-37).
Melt kneading was performed at 0 ° C. to prepare a composition. A test piece was prepared using the obtained composition, and the physical properties were measured. The results are shown in Table 1.

Comparative Example 2: 82.5 wt% of the polypropylene resin (PP-1) used in the example as the component (A) and 17.5 wt% of the EPR used in the example 1 as the component (B).
% With respect to 100 parts by weight of the resin composition of Example 1.
0.4 parts by weight of the nucleating agent used in Example 1 and commercial BHT0.
08 parts by weight, 0.05 parts by weight of Irganox 1010 and 0.1 parts by weight of calcium stearate were added, and the mixture was melt-kneaded at 200 ° C. using a twin-screw extruder (KTX-37) to prepare a composition. did. A test piece was prepared using the obtained composition, and the physical properties were measured. The results are shown in Table 1.

Comparative Example 3: 86.5 wt% of the polypropylene resin (PP-1) used in Example 1 as the component (A) and 16.5 w of the EPR used in Example 1 as the component (B).
t% and 1 wt% of the dispersion promoter (C) used in Example 1
% With respect to 100 parts by weight of the resin composition of Example 1.
0.4 parts by weight of the nucleating agent used in Example 1 and commercial BHT0.
08 parts by weight, 0.05 parts by weight of Irganox 1010 and 0.1 parts by weight of calcium stearate were added, and the mixture was melt-kneaded at 200 ° C. using a twin-screw extruder (KTX-37) to prepare a composition. did. A test piece was prepared using the obtained composition, and the physical properties were measured. The results are shown in Table 1.

Comparative Example 4: Cataloy 7057XOP manufactured by HIMONT Co., Ltd. as a component (A) polypropylene resin (PP-4) [MFR = 41.5, Q = 15.3,
(9-0.58 x logMFR = 8.1, 6.5-0.
58 × log MFR = 5.6), mmmm% = 98.
1] To 100 parts by weight of a resin composition consisting of 12.5 wt% of EPR used in Example 1 as component (B) in 82.5 wt% and 5 wt% of the dispersion accelerator (C) used in Example 1 0.4 part by weight of the nucleating agent used in Example 1, 0.08 part by weight of commercially available BHT, and Irganox 10
0.05 to 10 parts by weight, calcium stearate 0.1
Parts by weight were added and melt-kneaded at 200 ° C. using a twin-screw extruder (KTX-37) to prepare a composition. A test piece was prepared using the obtained composition, and the physical properties were measured. The results are shown in Table 1.

Comparative Example 5: 100 wt% of a resin composition comprising 75 wt% of the polypropylene resin (PP-3) used in Comparative Example 1 as the component (A) and 25 wt% of EPR used in the Example 1 as the component (B). 0.4 parts by weight of the nucleating agent used in Example 1, 0.08 parts by weight of commercially available BHT, 0.05 parts by weight of Irganox 1010, and 0.1 parts by weight of calcium stearate are added to parts by weight, Melt kneading at 200 ° C. using a twin-screw extruder (KTX-37),
A composition was made. A test piece was prepared using the obtained composition, and the physical properties were measured. The results are shown in Table 1.

Comparative Example 6: 55 wt% of the polypropylene resin (PP-3) used in Comparative Example 1 as the component (A), 25 wt% of the EPR used in Example 1 as the component (B), and Hayashi Kasei as the filler. With respect to 100 parts by weight of the resin composition containing 20% by weight of micelleton, 0.08 part by weight of commercially available BHT and 0.9% by weight of Irganox 1010 were further added.
05 parts by weight and 0.1 part by weight of calcium stearate were added, and the mixture was melt-kneaded at 200 ° C. using a twin-screw extruder (KTX-37) to prepare a composition. A test piece was prepared using the obtained composition, and the physical properties were measured. The results are shown in Table 2.

Comparative Example 7: 50 wt% of the polypropylene resin (PP-3) used in Comparative Example 1 as the component (A), 30 wt% of EPR used in the Example 1 as the component (B), and Hayashi Kasei as the filler. With respect to 100 parts by weight of the resin composition containing 20% by weight of micelleton, 0.08 part by weight of commercially available BHT and 0.9% by weight of Irganox 1010 were further added.
05 parts by weight and 0.1 part by weight of calcium stearate were added, and the mixture was melt-kneaded at 200 ° C. using a twin-screw extruder (KTX-37) to prepare a composition. A test piece was prepared using the obtained composition, and the physical properties were measured. The results are shown in Table 2.

Comparative Example 8: 50 wt% of the polypropylene resin (PP-3) used in Comparative Example 1 as the component (A), 25 wt% of EPR used in the Example 1 as the component (B), and Hayashi Kasei Co., Ltd. as the filler. With respect to 100 parts by weight of the resin composition containing 25% by weight of micelleton, 0.08 part by weight of commercially available BHT and 0.9% by weight of Irganox 1010 were further added.
05 parts by weight and 0.1 part by weight of calcium stearate were added, and the mixture was melt-kneaded at 200 ° C. using a twin-screw extruder (KTX-37) to prepare a composition. A test piece was prepared using the obtained composition, and the physical properties were measured. The results are shown in Table 2.

Comparative Example 9: 45 wt% of the polypropylene resin (PP-1) used in Example 1 as the component (A), 30 wt% of the EPR used in Example 1 as the component (B), and Hayashi Kasei as the filler. With respect to 100 parts by weight of the resin composition containing 25% by weight of micelleton, 0.08 part by weight of commercially available BHT and 0.9% by weight of Irganox 1010 were further added.
05 parts by weight and 0.1 part by weight of calcium stearate were added, and the mixture was melt-kneaded at 200 ° C. using a twin-screw extruder (KTX-37) to prepare a composition. A test piece was prepared using the obtained composition, and the physical properties were measured. The results are shown in Table 2.

Comparative Example 10: 55 wt% of the polypropylene resin (PP-3) used in Comparative Example 1 as the component (A), 20 wt% of EPR used in the Example 1 as the component (B),
To 100 parts by weight of a resin composition comprising 5 wt% of the dispersion accelerator (C) used in Example 4 and 20 wt% of Micelleton manufactured by Hayashi Kasei as a filler, further commercially available BH
T0.08 parts by weight, Irganox 1010 0.05
Parts by weight, 0.1 parts by weight of calcium stearate,
A composition was produced by melt-kneading at 200 ° C. using a twin-screw extruder (KTX-37). A test piece was prepared using the obtained composition, and the physical properties were measured. The results are shown in Table 2.

[0043]

[Table 1]

[0044]

[Table 2]

[0045]

EFFECTS OF THE INVENTION It is well known that a rubber-like substance such as ethylene-propylene rubber blended to improve the low temperature impact resistance of polypropylene resin deteriorates the physical properties such as rigidity and heat resistance of polypropylene resin. . The present invention has developed a polypropylene-based resin composition in which the low-temperature impact resistance is sufficiently improved and the physical properties such as rigidity and heat resistance are prevented from being deteriorated even when the amount of the rubber-like substance is small.

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) C08L 23/00-23/36

Claims (3)

(57) [Claims] 1. (A) The isotactic pentad fraction (mmmm%) of the propylene chain is 99.0 or more, and the Q value (Mw / Mn) obtained from GPC is expressed by the relational expression (1) 9-0. 58 x log MFR (g / 10 min)>Q> 6.5-0.58 x log MFR (g / 10 min) ... (1) (However, MFR is JIS K7210, Table 1, Condition 14)
Is the melt flow rate. 4 to 49 wt% satisfying the above conditions, (B) ethylene-propylene rubber 10 to 50 wt%, and (C) a copolymer containing a moiety consisting of an α-olefin having 4 or more carbon atoms and ethylene as a dispersion promoter, 2 to 10 wt%. % Polypropylene resin composition. 2. The polypropylene-based resin composition according to claim 1, wherein the ethylene-propylene rubber as the component (B) has an MFR of 0.1 to 10 g / 10 minutes and an ethylene content of 40 to 90 wt%. 3. The polypropylene resin composition according to claim 1, wherein the dispersion accelerator as the component (C) is a block copolymer containing a block of ethylene or styrene.