JPH09157492A - Thermoplastic resin composition - Google Patents

Abstract

(57) Abstract: A thermoplastic resin composition excellent in impact resistance, rigidity and moldability is provided. [A] A propylene-ethylene block copolymer obtained by multi-stage polymerization, comprising: (a) 70 to 95% by weight of a homopolypropylene moiety satisfying a predetermined relational expression between the heat of fusion and MFR; b) Propylene-containing 5 to 30% by weight of a propylene-ethylene copolymerization part containing (i) a low ethylene concentration propylene-ethylene copolymerization part and (ii) a high ethylene concentration propylene-ethylene copolymerization part. A thermoplastic resin composition comprising 55 to 85 parts by weight of an ethylene block copolymer, [B] 5 to 20 parts by weight of a polyolefin elastomer, and [C] 10 to 25 parts by weight of talc.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a thermoplastic resin composition, and more particularly to a thermoplastic resin composition having excellent impact resistance, rigidity and moldability.

[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 and rigidity, a rubber component such as ethylene-propylene copolymer rubber (EPR) and an inorganic filler such as talc are added to a propylene-ethylene block copolymer for the purpose of improvement. Various polypropylene resin compositions have 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.

However, this resin composition includes fine talc having an average particle size of 1.0 μm or less as talc. The fine talc easily forms agglomerates, and when the agglomerates are formed, hardness and rigidity are increased. Also, the balance of mechanical strength such as 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 (adsorptiveness) is enhanced, and thus there is a problem that talc adsorbs various additives. Therefore,
With aminosilane-based treatment agents and titanate-based treatment agents,
It has been attempted to improve the dispersibility of fine talc and suppress the adsorption of additives by subjecting talc to a surface treatment, but it does not yet have a sufficient effect.

Further, in Japanese Patent Laid-Open No. 6-263961, (a)
Propylene-ethylene block copolymer having a melt flow rate of 10 to 100 g / 10 min, or the propylene-ethylene block copolymer more than 80% by weight 100
100 parts by weight of a polyolefin resin component consisting of less than 20% by weight and less than 20% by weight of olefin elastomer, (b) an average particle size of 1 μm treated with modified silicone
A polyolefin resin composition containing the following 1 to 67 parts by weight of talc is disclosed. However, in the case of manufacturing a large-sized molded product having a complicated shape by injection molding, it is necessary to further improve mechanical strength, moldability and the like.

As described above, at present, a polypropylene resin composition having a good balance of impact resistance, rigidity and moldability has not yet been obtained. If these problems are solved, it is expected that the range of use of polypropylene-based resin materials will be expanded, the number of parts that can be covered with one material will increase, and that the development will be advantageous in terms of cost.

Accordingly, the object of the present invention is to provide impact resistance,
It is intended to provide a thermoplastic resin composition having excellent rigidity and moldability.

[0008]

In view of the above object, the inventors of the present invention have conducted extensive studies and as a result, as a result, a homopolypropylene portion having a predetermined relationship between the heat of fusion and the melt flow rate, and a low ethylene concentration of propylene- An ethylene copolymer portion and a propylene-ethylene block copolymer consisting of a propylene-ethylene copolymer portion having a high ethylene concentration are produced by multi-step polymerization, and by adding a polyolefin elastomer and talc thereto, impact resistance and rigidity are improved. Further, they have found that a thermoplastic resin composition having excellent moldability can be obtained, and have conceived the present invention.

That is, the thermoplastic resin composition of the present invention is [A] a propylene-ethylene block copolymer obtained by multi-stage polymerization, and (a) has a melt flow rate (MFR) measured according to ASTM D-1238. ) Is in the range of 100 to 500 g / 10 minutes, and the heat of fusion (ΔH _m ) and MFR obtained from differential scanning calorimetry satisfy the relational expression ΔH _m ≧ 24.5 + 1.583 log MFR 70. ~ 95
% By weight, and (b) (i) a low ethylene concentration propylene-ethylene copolymerization portion (ethylene content in the copolymerization portion is 30 to 50% by weight, and intrinsic viscosity is 2 to 5 dl / g). And (ii) propylene-ethylene containing a high ethylene concentration propylene-ethylene copolymerized portion (ethylene content in the copolymerized portion is 50 to 70% by weight, and intrinsic viscosity is 4 to 6 dl / g). 55 to 85 parts by weight of a propylene-ethylene block copolymer composed of a copolymerized portion of 5 to 30% by weight, and [B] (c) MFR of 0.1 to 30 g / 10 min ethylene-butene copolymer rubber 5 to 20 5 to 20 parts by weight of a polyolefin-based elastomer containing, by weight, (d) an MFR of 0.1 to 20 g / 10 minutes, an ethylene-propylene copolymer rubber of 0 to 15 parts by weight, and [C] an average particle diameter of 5 μm or less. Talc 10-25 And a total of 10 parts by weight of the (b) propylene-ethylene copolymerization part and the [B] polyolefin-based elastomer.
The content of the (i) propylene-ethylene copolymerization portion having a low ethylene concentration is 10 to 40% by weight based on 0% by weight.

[0010]

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described in detail below. [I] Each Component of Thermoplastic Resin Composition The thermoplastic resin composition of the present invention comprises [A] a propylene-ethylene block copolymer, [B] a polyolefin-based elastomer, [C] talc, and optionally blended. Yes [E] Consists of other additives.

[A] Propylene-Ethylene Block Copolymer [1] Structure and Physical Properties The propylene-ethylene block copolymer used in the present invention comprises a substantially crystalline homopolypropylene moiety and a propylene-ethylene copolymer moiety. It is composed of a small amount of a crystalline homopolyethylene part, and each part may exist as a single polymer or may be in a state where they are bonded. The above-mentioned parts are basically composed of propylene and / or ethylene, but may contain a small amount of other α-olefin, diene-based monomer or the like.

(1) Crystalline homopolypropylene portion The crystalline homopolypropylene portion is ASTM D-12.
Melt flow rate (MFR) measured according to No. 38 (230 ° C., load 2.16 kg) is 100 to 500 g / 1.
It is 0 minutes, preferably 150 to 400 g / 10 minutes. M
When FR is less than 100 g / 10 minutes, the moldability is low, while 5
If it exceeds 00, the impact resistance decreases.

It is also necessary that the heat of fusion (ΔH _m ) obtained from the differential scanning calorimetry (DSC) measurement 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, the rigidity and hardness are low.

The ΔH _m in the present invention is the heat of fusion measured while raising the temperature of the sample to 200 ° C.
The peak between 5 ° C and 175 ° C is taken as the melting peak, and the corresponding heat quantity is divided by the sample quantity to calculate the heat of fusion (unit cal / g).

(2) Propylene-ethylene copolymerization portion The propylene-ethylene copolymerization portion is composed of a low ethylene concentration propylene-ethylene copolymerization portion and a high ethylene concentration propylene-ethylene copolymerization portion.

(I) Propylene-ethylene copolymerization portion with low ethylene concentration The content of ethylene in the propylene-ethylene copolymerization portion with low ethylene concentration is 30 to 50% by weight, preferably 35 to 50% by weight.
It is 45% by weight. When the ethylene content is less than 30% by weight, the rigidity is low, while when it exceeds 50% by weight, the affinity with the crystalline homopolypropylene portion is lowered. The intrinsic viscosity [η] _L of the propylene-ethylene copolymerized portion is 2 to
It is 5 dl / g, preferably 3 to 5 dl / g. When the intrinsic viscosity [η] _L is less than 2 dl / g, the effect of improving the rigidity is not sufficient, while when it exceeds 5 dl / g, the appearance of the molded product becomes poor due to the increase of the gel component.

(Ii) Propylene-ethylene copolymerization portion having a high ethylene concentration The ethylene content of the propylene-ethylene copolymerization portion having a high ethylene concentration is 50 to 70% by weight, preferably 55 to 50% by weight.
65% by weight. If the ethylene content is less than 50% by weight, the effect of improving the impact resistance is not sufficient, while if it exceeds 70% by weight, the impact resistance decreases. Propylene-
The intrinsic viscosity [η] _H of the ethylene copolymerized portion is 4 to 6 dl /
g, preferably 4-5 dl / g. Intrinsic viscosity [η]
_{When H} is less than 4 dl / g, the impact resistance improving effect is not sufficient, while when it exceeds 6 dl / g, the appearance of the molded product becomes poor due to an increase in gel component. Further, from the viewpoint of improving the impact resistance at low temperature, [η] _H is preferably larger than [η] _L.

(3) Ratio of homopolypropylene portion and propylene-ethylene copolymer portion As for the content of the crystalline homopolypropylene portion and propylene-ethylene copolymer portion, the sum of these is 100.
The crystalline homopolypropylene portion is 70 to 70% by weight.
It is 95% by weight, preferably 80 to 90% by weight, and the propylene-ethylene copolymerized portion is 5 to 30% by weight, preferably 10 to 20% by weight. Even if it contains a crystalline homopolyethylene portion, its content is 3% by weight or less.

When the crystalline homopolypropylene portion is less than 70% by weight (when the propylene-ethylene copolymer portion exceeds 30% by weight), the rigidity is low. On the other hand, when the crystalline homopolypropylene portion exceeds 95% by weight (when the propylene-ethylene copolymer portion is less than 5% by weight),
The ductility decreases.

The content of the propylene-ethylene copolymerized portion can be determined by measuring the proportion of the soluble portion in cold xylene.

[2] Production Method The propylene-ethylene block copolymer as described above is obtained by sequentially polymerizing a crystalline homopolypropylene portion, a low-ethylene concentration propylene-ethylene copolymer portion and a high-ethylene concentration. To be The polymerization order of each component in such multi-stage polymerization is not particularly limited, but from the viewpoint of productivity, first, a crystalline homopolypropylene portion (which may contain a small amount of comonomer component) is produced, and then the next step. It is preferable to switch to (ethylene + propylene) to produce a low-ethylene concentration propylene-ethylene copolymerization portion, and then produce a high-ethylene concentration propylene-ethylene copolymerization portion.

(1) Formation of Crystalline Homopolypropylene Portion The crystalline homopolypropylene portion is not particularly limited in its production method as long as it satisfies the above-mentioned physical properties, but is preferably produced by the following method.

(I) Polymerization catalyst (A) A solid component containing magnesium, titanium, a halogen, and an electron-donating compound as essential components, (B) an organoaluminum compound, and (C) an organosilicon represented by the general formula (I). Compound and (D) optionally in the presence of an electron-donating compound,
(E) The catalyst component (hereinafter referred to as “preliminary polymerization catalyst component”) is obtained by prepolymerizing the olefin by contacting with the olefin.
That. ) Is prepared, and an organometallic compound and, if necessary, an electron donating compound are combined therewith to obtain a propylene polymerization catalyst.

The general formula (I) of the organosilicon compound as the component (C) is as follows.

Embedded image (However, R ¹ is a cyclic substituent having an ether bond or a thioether bond in the ring, an oxy group having an in-ring ether bond-containing cyclic substituent, an in-ring ketone bond-containing cyclic substituent, a nitrogen atom-containing heterocyclic substituent. Group, a silicon atom-containing heterocyclic substituent, or a substituent having a lactone skeleton structure, R ² is a hydrocarbon group having 1 to 10 carbon atoms, R ⁴ O—,
R ⁵ Si- or R ⁶ ₃ SiO- (wherein R ⁴ is a hydrocarbon group having 3 to 10 carbon atoms, R ⁵ and R ⁶ are each a hydrocarbon group having 1 to 10 carbon atoms, R ³ is a methyl group or an ethyl group, x is 1 or 2, y is 0 or 1, and z is the same or different.
Is 2 or 3 and x + y + z = 4. )

Ingredient (A) in the present invention is disclosed in JP-A-63-
No. 264607, No. 58-198503, No. 62-1
As disclosed in Japanese Patent No. 46904 and the like, magnesium metal, halogenated hydrocarbons and the general formula X ¹ _n M (O
R ⁷ ) _mn compound (in the formula, X ¹ is a hydrogen atom, a halogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and
Is a boron, carbon, aluminum, silicon or phosphorus atom, R ⁷ is a hydrocarbon group having 1 to 20 carbon atoms, m is a valence of M, and m> n ≧ 0. ) Contacting the magnesium-containing solid obtained by contacting with a halogen-containing alcohol, and then contacting with an electron-donating compound and a titanium compound, magnesium dialkoxide and a silicon halide compound having a hydrogen-silicon bond After that, a method of contacting with a titanium halide compound and then with an electron-donating compound (and further contacting with a titanium halide compound if necessary),
It can be prepared by, for example, bringing a magnesium dialkoxide and a silicon halide compound having a hydrogen-silicon bond into contact with each other, then bringing them into contact with an electron-donating compound, and then bringing them into contact with a titanium compound, and the most preferable method is.

The component (A) is prepared as described above, but the component (A) is, if necessary, a saturated aliphatic hydrocarbon such as hexane, heptane, octane or the like, and saturated fat such as cyclopentane or cyclohexane. It may be washed with an inert medium such as a cyclic hydrocarbon, an aromatic hydrocarbon such as benzene, toluene or xylene, and may be further dried.

(B) Organoaluminum Compound Specific examples of the organoaluminum compound (hereinafter referred to as the component (B)) include trimethylaluminum, triethylaluminum, tripropylaluminum, triisopropylaluminum, tributylaluminum, triisobutylaluminum, triisobutylaluminum and triisobutylaluminum. Hexylaluminum and the like can be mentioned.

(C) Organosilicon Compound The organosilicon compound which is a component of the catalyst of the present invention (hereinafter referred to as component (C)) is represented by the above general formula (I).
In the formula, R ¹ is a cyclic substituent having an ether or thioether bond in the ring, an oxy group of a cyclic substituent having an ether bond in the ring, a cyclic substituent having a ketone bond in the ring, a heterocyclic substituent having a nitrogen atom, silicon An atom-containing heterocyclic substituent, a substituent having a lactone skeleton structure, R ² is a hydrocarbon group having 1 to 10 carbon atoms, R ⁴ O-, R ⁵ ₃ Si-
Or R ⁶ ₃ SiO— (provided that R ⁴ is a hydrocarbon group having 3 to 10 carbon atoms, R ⁵ and R ⁶ are each a hydrocarbon group having 1 to 10 carbon atoms), and R ³ is a methyl group or an ethyl group, x is 1 or 2, y is 0 or 1, z is 2 or 3, and x + y + z = 4. Specific examples of R ¹ are shown below (each R ¹ group is represented by RA, RB, ...).

Embedded image

R ² in the above general formula of the component (C),
Examples of the hydrocarbon group in R ⁴ , R ⁵ and R ⁶ include an alkyl group, an alkenyl group, a cycloalkyl group, a cycloalkenyl group, a cycloalkadienyl group, an aryl group and an aralkyl group. As the alkyl group, ethyl, i
-Propyl, s-butyl, t-butyl, amyl, 2-ethylhexyl, decyl group and the like, and the alkenyl group includes vinyl, allyl, propenyl, 1-hexenyl, 1-octenyl, 1-methyl-1-. Examples thereof include a pentynyl group, examples of the cycloalkyl group include a cyclopentyl group and a methylcyclohexyl group, examples of the cycloalkenyl group include a cyclopentenyl group and cyclohexenyl group, and examples of the cycloalkadienyl group include cyclopentadiene group. Examples of the aryl group include phenyl, tolyl, and a methylcyclopentadienyl group.
Examples thereof include a xylyl group and the like, and examples of the aralkyl group include a benzyl, phenethyl, 1-phenylpropyl group and the like.

Examples of the component (C) are shown below. [RA],
The symbols such as [RB] ... Correspond to the above symbols of R ¹ in the general formula (I) of the component (C). [RA] ₂ Si
(OMe) ₂ , [RB] (i-Pr) Si (OM
e) ₂ , [RC] (t-Bu) Si (OMe) ₂ , [R
C] (Me ₃ SiO) Si (OMe) ₂ , [RA] (i
-Pr) Si (OEt) ₂ , [RA] Si (OM
e) ₃ , [RD] Si (OMe) ₃ , [RB] Si (O
Et) ₃ , [RE] MeSi (OMe) ₂ , [RF]
(I-PrO) Si (OMe) ₂ , [RG] (i-P
r) Si (OEt) ₂ , [RH] Si (OMe) ₃ ,
[RI] Si (OEt) ₃ , [RJ] Si (OSiM
e) (OMe) ₂ , [RK] Si (OEt) ₃ , [R
L] Si (OEt) ₃ , [RM] Si (OEt) ₃ ,
[RN] Si (OEt) ₃ .

(D) Electron-donating compound Component (D) comprises an organosilicon compound (component
(Except (C)) electron-donating compounds and electron-donating compounds containing heteroatoms such as nitrogen, sulfur, oxygen and phosphorus can be used, but organosilicon compounds are preferred. The organosilicon compound is preferably one having a total of 4 alkoxy groups (which may be partially substituted with an alkyl group or an aryl group) bonded to a silicon atom. These alkyl groups and alkoxy groups may be chain or cyclic. Further, the alkyl group or the aryl group may be substituted with a halogen element.

Such an organosilicon compound (component (D))
Specific examples of tetramethoxysilane, tetraisobutoxysilane, tetraphenoxysilane, tetrabenzyloxysilane, methyltrimethoxysilane, methyltriethoxysilane, methyltriphenoxysilane, ethyltriethoxysilane, butyltriethoxysilane,
Butyltriphenoxysilane, vinyltriethoxysilane, allyltrimethoxysilane, dimethyldiisopropoxysilane, dimethyldiphenoxysilane, diethyldiethoxysilane, diethyldiisobutoxysilane, diethyldiphenoxysilane, dibutyldiisopropoxysilane, dibutyldibutoxysilane Silane, dibutyldiphenoxylan, diisobutyldiethoxysilane, diphenyldimethoxysilane, diphenyldibutoxysilane, dibenzyldiethoxysilane, divinyldiphenoxysilane,
Examples thereof include diallyldipropoxysilane, diphenyldiallyloxysilane, chlorophenyldiethoxysilane and the like.

Two or more kinds of these electron donating compounds (D) may be used. Further, these electron donating compounds may be added when the organoaluminum compound is used in combination with the catalyst component, or may be added after being brought into contact with the organoaluminum compound in advance.

(E) Olefin As olefins, in addition to ethylene, propylene and 1-
Α such as butene, 1-hexene, 4-methyl-1 penten
-Olefins can be used.

(Ii) Prepolymerization In the presence of an organoaluminum compound (component (B)) and an organosilicon compound (component (C)), a solid component (component (A)) is contacted with an olefin (component (E)). By doing so, the olefin is prepolymerized. Further, it is preferable to add an electron-donating compound (component (D)) together with the component (B) and the component (C) at the time of prepolymerization, if necessary. The prepolymerization is preferably performed in the presence of the above-mentioned inert medium. The prepolymerization is usually performed at a temperature of 100 ° C or lower, preferably -30 ° C to +.
It is carried out at a temperature of 30 ° C, more preferably -20 ° C to + 15 ° C. The polymerization system may be either a batch system or a continuous system, or may be performed in two or more stages. When the reaction is carried out in multiple stages, the polymerization conditions can of course be changed.

Component (B) has a concentration of 10 to 10 in the prepolymerization system.
It is used in an amount of 500 mmol / liter, preferably 30-200 mmol / liter, and is 1-50,000 mol, preferably 2-1,000 mol, per 1 gram atom of titanium in the component (A). To use. component
(C) is used so that the concentration in the prepolymerization system is 5 to 1,000 mmol / liter, preferably 10 to 200 mmol / liter. Further, the component (D) used as necessary has a concentration in the prepolymerization system of 1 to 100 mmol /
It is used in an amount of 1 liter, preferably 5 to 50 mmol / liter. Olefin polymer is incorporated into component (A) by prepolymerization, but the amount of polymer is
(A) 0.1 to 200 g per 1 g, especially 0.5 to 50 g is desirable. The catalyst component of the present invention prepared as described above can be diluted or washed with the above-described inert medium, but it is particularly preferable to wash it from the viewpoint of preventing storage deterioration of the catalyst component. After washing, it may be dried if necessary. Also, when storing the catalyst component,
It is desirable to store at the lowest possible temperature, -50 ℃ to +
A temperature range of 30 ° C, especially -20 ° C to + 5 ° C, is recommended.

(Iii) Main Polymerization The precatalyst component obtained as described above is combined with an organometallic compound and, if necessary, an electron-donating compound, and then homopolymerized with propylene or co-polymerized with other monoolefins. By performing main polymerization such as polymerization, the heat of fusion (ΔH _m ) and MF obtained from the differential scanning calorimetry (DSC) measurement
It is possible to obtain a crystalline polypropylene whose relation with R is represented by the above relational expression.

The organometallic compound which can be used in the main polymerization is an organic compound of Group I to Group III metal of the periodic table. As the organic metal compound, an organic compound of lithium, magnesium, calcium, zinc or aluminum can be used, and an organic aluminum compound is particularly preferable. The organoaluminum compound has a general formula: R ⁸ _p AlX ² _3-p (wherein R ⁸ is an alkyl group or an aryl group, X ² is a halogen atom, an alkoxy group or a hydrogen atom, and p is 1 ≦ p ≦ 3. And an alkylaluminum compound such as trialkylaluminum, dialkylaminium monohalide, monoalkylaluminum dihalide, dialkylaluminum monoalkoxide and alkylaluminum monohydride, Alternatively, a mixture or complex compound thereof is particularly preferable. The organoaluminum compound preferably has 1 to 18 carbon atoms, more preferably 2 to 6 carbon atoms.

Specifically, trialkyl aluminum such as trimethyl aluminum, triethyl aluminum and triisobutyl aluminum, dimethyl aluminum chloride, diethyl aluminum bromide, dialkyl aluminum monohalide such as diethyl aluminum iodide, methyl aluminum dichloride, ethyl aluminum dibromide. , Monoalkyl aluminum dihalides such as ethyl aluminum diiodide, alkyl aluminum sesquihalides such as methyl aluminum sesquichloride, diethyl aluminum ethoxide,
Examples thereof include dialkyl aluminum monoalkoxides such as diethyl aluminum phenoxide and diisobutyl aluminum ethoxide, and dialkyl aluminum hydrides such as dimethyl aluminum hydride, diethyl aluminum hydride and dipropyl aluminum hydride. Among these, trialkylaluminum is preferable, and triethylaluminum and triisobutylaluminum are particularly preferable. Further, these trialkylaluminums are other organic aluminum compounds, for example, industrially easily available diethylaluminum chloride, ethylaluminum dichloride, ethylaluminum sesquichloride, diethylaluminum ethoxide, diethylaluminum hydride or a mixture or complex compound thereof. Etc. can be used together.

The electron donating compound which can be optionally combined with the prepolymerization catalyst component and the organometallic compound is an electron donating compound (D) which may be used in the prepolymerization of the component (A). And carboxylic acids, carboxylic acid anhydrides, carboxylic acid esters, carboxylic acid halides, alcohols, ethers, ketones, amines, amides, nitriles, aldehydes, alcoholates, organic groups Phosphorus bonded through carbon or oxygen,
Examples include arsenic or antimony compounds, phosphoamides, thioethers, thioesters, carbonates and the like. Among these, carboxylic acids, carboxylic acid anhydrides, carboxylic acid esters, carboxylic acid halides, alcohols, ethers and the like are appropriately selected. Two or more kinds of these electron donating compounds may be used. Further, these electron donating compounds may be used when the organometallic compound is used in combination with the catalyst component, or may be used after being brought into contact with the organometallic compound in advance.

The amount of the organometallic compound used with respect to the pre-catalyst component is usually 1 to 2,000 gram moles, preferably 20 to 500 gram moles per gram atom of titanium in the catalyst component. When an electron donating compound is used, the amount of the organometallic compound (as aluminum) is 0.1 to 40 g atom, preferably 1 to 25 g atom per mol of the electron donating compound, so that the amount of the organo metal compound is 1 to 25 g atom. Select the ratio of electron-donating compounds.

The propylene polymerization reaction may be carried out in either a gas phase or a liquid phase. When the polymerization is carried out in a liquid phase, normal butane, isobutane, normal pentane, isopentane, hexane, heptane, octane, cyclohexane, benzene, toluene, It can be carried out in an inert hydrocarbon such as xylene and in a liquid monomer. The polymerization temperature is usually -8.
The temperature range is 0 ° C to + 150 ° C, particularly 40 ° C to 120 ° C. The polymerization pressure may be, for example, 1 to 60 atm. Further, the molecular weight of the obtained polymer is controlled by the presence of hydrogen or other known molecular weight regulator. The polymerization reaction is carried out in a continuous or batch reaction, and the conditions may be those normally used. Also, the polymerization reaction may be carried out in one stage or in two stages.

(2) Production of propylene-ethylene copolymerization portion After producing the crystalline homopolypropylene portion, it is introduced by switching to (ethylene + propylene) in the presence of the polypropylene polymerization catalyst, Ziegler catalyst and the like. By adjusting the ratio of ethylene and propylene, a low-ethylene concentration propylene-ethylene copolymerization part and a high-ethylene concentration propylene-ethylene copolymerization part are produced in two stages. The polymerization order of these propylene-ethylene copolymerized portions is not particularly limited, but from the viewpoint of productivity, first, a low-ethylene concentration propylene-ethylene copolymerized portion is produced, and then a high-ethylene concentration propylene-ethylene copolymerized portion is produced. Is preferably produced.

The polymerization conditions in the propylene-ethylene copolymerization reaction can be appropriately selected from the range of the above-mentioned propylene polymerization conditions. The ethylene content of the propylene-ethylene copolymerization part is determined by sampling the reaction mixture and measuring the NMR spectrum.

[B] Polyolefin-based Elastomer The polyolefin-based elastomer used in the present invention is an ethylene-butene copolymer rubber alone or a combination of an ethylene-butene copolymer rubber and an ethylene-propylene copolymer rubber. Impact resistance can be improved by compounding.

(1) Ethylene-Propylene Copolymer Rubber MFR of Ethylene-Propylene Copolymer Rubber (EPR)
Is 0.1 to 20 g / 10 minutes, preferably 0.5 to 10
g / 10 minutes is more preferable. If the MFR is less than 0.1 g / 10 minutes, the moldability will decrease, while if it exceeds 20 g / 10 minutes, the mechanical strength will decrease. Also handling,
From the viewpoint of productivity, the content of ethylene in EPR is 70-
Those having a content of 80 mol% and a propylene content of 30 to 20 mol% are preferable, and those having an ethylene content of 75 to 80 mol% and a propylene content of 25 to 20 mol% are more preferable.

(2) Ethylene-butene copolymer rubber The MFR of ethylene-butene copolymer rubber (EBR) is
0.1 to 30 g / 10 minutes, preferably 0.5 to 10 g /
10 minutes. If the MFR is less than 0.1 g / 10 minutes, the moldability will decrease, while if it exceeds 30 g / 10 minutes, the mechanical strength will decrease. Further, from the viewpoint of handling property, productivity, etc., the ethylene content is 75 to 90 mol%, butene-
The content of 1 is preferably 25 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 a weight average particle diameter 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 with it). It is considered that this is because the dispersibility of talc in ethylene-propylene copolymer rubber and ethylene-butene copolymer rubber) becomes good, and the adsorbability of various additives to talc decreases significantly. .

[II] Blending Ratio The blending ratio of each component is 55 to 85 parts by weight, preferably 55 to 75 parts by weight, and 5 to 20 parts by weight, preferably 5 to 20 parts by weight, for the propylene-ethylene block copolymer. Is 10 to 20 parts by weight, and talc is 10
-25 parts by weight, preferably 15-25 parts by weight. In the polyolefin-based elastomer, the ethylene-butene copolymer rubber is 5 to 20 parts by weight, preferably 5-1.
5 parts by weight, and the ethylene-propylene copolymer rubber is 0 to 15 parts by weight, preferably 5 to 10 parts by weight.

In the propylene-ethylene block copolymer, the ratio of the low-ethylene concentration propylene-ethylene copolymer portion is such that the entire rubber component (low-ethylene concentration propylene-ethylene copolymer portion + high-ethylene concentration propylene-ethylene copolymer 10-40% by weight, preferably 10%, based on the polymerized portion + polyolefin-based elastomer)
~ 25% by weight.

When the blending amount of the propylene-ethylene block copolymer is less than 55 parts by weight, the ductility, hardness and the like tend to be lowered, while when it exceeds 85 parts by weight, the impact resistance is lowered.
When the amount of the polyolefin-based elastomer is less than 5 parts by weight, the impact resistance is low, while when it exceeds 20 parts by weight, the elastic modulus is lowered. Further, in the olefin-based elastomer, when the ratio of the ethylene-butene copolymer rubber is less than 5 parts by weight, the ductility is low. When the amount of talc is less than 10 parts by weight, rigidity and heat resistance are low, while when it exceeds 25 parts by weight, impact resistance is lowered. In addition, the propylene-ethylene block copolymer has a low ethylene concentration of propylene-
If the proportion of the ethylene copolymerized portion is less than 10 parts by weight, the ductility is low, while if it exceeds 40 parts by weight, the impact resistance at low temperature is deteriorated.

[III] Other Additives The thermoplastic resin composition of the present invention has, for the purpose of modification, for example, a crystal nucleating agent, a heat stabilizer, an antioxidant, a light stabilizer, a flame retardant, a plasticizer. Agents, antistatic agents, release agents, foaming agents, coloring agents, pigments and the like can be added.

[IX] Method for producing thermoplastic resin composition In the thermoplastic resin composition of the present invention, the above components are mixed using a Henschel mixer, a super mixer, a ribbon blender, etc., and a single screw extruder, a twin screw extruder, It can be obtained by melt-kneading in a temperature range of 170 to 250 ° C. with a Banbury mixer, a kneader or the like.

The talc treated with the modified silicone has a resin component (propylene-ethylene block copolymer alone or a polyolefin elastomer with it).
Or talc 50 to 80% by weight and propylene-ethylene block copolymer (or crystalline homopolypropylene) 20 to 20% by weight.
A so-called masterbatch having a high talc content is prepared in advance by melt-kneading with 50% by weight, and a propylene-ethylene block copolymer (in some cases, a polyolefin-based elastomer) is added thereto in a predetermined talc compounding amount. You may mix so that it may become. By blending talc by such a method, the dispersibility of talc in the propylene-ethylene block copolymer can be further improved. In the production of the masterbatch, crystalline homopolypropylene may be used instead of the propylene-ethylene block copolymer.
However, the amount used is about 20% by weight or less based on 100% by weight of the entire resin component.

[0058]

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. Production Example 1 of propylene-ethylene block copolymer (BPP1)
Preparation of catalyst component (A) In a 1 liter reaction vessel equipped with a reflux condenser, under a nitrogen gas atmosphere, chip-shaped metallic magnesium (purity: 99.
5%, 8.3 g of average particle size 1.6 mm) and 250 ml of n-hexane were added, stirred for 1 hour at 68 ° C., metallic magnesium was taken out, and dried under reduced pressure at 65 ° C. to obtain pre-activated metallic magnesium. .

Next, 140 ml of n-butyl ether and an n-butyl ether solution of n-butyl magnesium chloride (1.
(75 mol / l) to a suspension of 0.5 ml
The temperature was maintained at 0 ° C., and a solution of 38.5 ml of n-butyl chloride dissolved in 50 ml of n-butyl ether was added dropwise over 50 minutes. After conducting the reaction at 70 ° C. for 4 hours with stirring, the reaction solution was kept at 25 ° C.

Next, HC (OC ₂ H ₅ ) ₃ was added to this reaction solution.
55.7 ml was added dropwise over 1 hour. After dropping, 6
The reaction was carried out at 0 ° C. for 15 minutes, the reaction product solid was washed 6 times with 300 ml of n-hexane each time, and dried under reduced pressure at room temperature for 1 hour, and a magnesium-containing solid 31. 6 g was recovered.

In a 300 ml reaction vessel equipped with a reflux condenser, a stirrer and a dropping funnel, 6.3 g of magnesium-containing solid and 50 ml of n-heptane under a nitrogen gas atmosphere.
To prepare a suspension and stir at room temperature while stirring 2,2,2-
A mixed solution of 20 ml (0.02 mmol) of trichloroethanol and 11 ml of n-heptane was added from a dropping funnel to 30
The mixture was added dropwise over a period of 1 minute and further stirred at 80 ° C. for 1 hour. The solid obtained was filtered off and 100 ml of n-hexane at room temperature was added.
Was washed 4 times with 100 ml of toluene and then twice with 2 times to obtain a solid component.

40 ml of toluene was added to the above solid component, titanium tetrachloride was further added so that the volume ratio of titanium tetrachloride / toluene was 3/2, and the temperature was raised to 90 ° C. After stirring, a mixed solution of 2 ml of di-n-butyl phthalate and 5 ml of toluene was added dropwise, and then the mixture was stirred at 120 ° C. for 2 hours. The solid substance obtained was filtered off at 90 ° C.
Wash twice with ml at 90 ° C. Furthermore, titanium tetrachloride was newly added so that the volume ratio of titanium tetrachloride / toluene was 3/2, and the mixture was stirred at 120 ° C. for 2 hours, and the mixture was heated at room temperature to 100
5. Catalyst component (A) after washing 7 times with ml of n-hexane 5.
5 g were obtained.

Prepolymerization (adjustment of prepolymerization catalyst components) In a 500 ml reactor equipped with a stirrer, 3.5 g of the component (A) obtained above and 300 ml of n-heptane were put in a nitrogen gas atmosphere and stirred. While cooling to 5 ° C.
Next, n-heptane solution of triethylaluminum (TEAL) (2.0 mol / liter) and 2,3,4-trimethyl-3-azacyclopentyltrimethoxysilane were added to TEAL and 2,3,4-trimethyl in the reaction system. -3-Azacyclopentyltrimethoxysilane was added so that the concentrations thereof were 100 mmol / liter and 10 mmol / liter, respectively, and the mixture was stirred for 5 minutes.

Next, after depressurizing the system, propylene gas was continuously introduced to polymerize propylene for 2.2 hours. After completion of the polymerization, propylene in the gas phase was purged with nitrogen gas, and the solid phase portion was washed with 100 ml of n-hexane three times at room temperature. Further, the solid phase portion was dried under reduced pressure at room temperature for 1 hour to prepare a prepolymerization catalyst component. As a result of measuring the amount of magnesium contained in the prepolymerization catalyst component, the prepolymerization amount was 3.1 g per 1 g of the component (A).

In a 5-liter stainless steel autoclave equipped with a main polymerization stirrer, 4 ml of a TEAL n-heptane solution (0.3 mol / liter) and a diisopropoxydimethoxysilane n-heptane solution (0 0.08 mol / liter) 3 ml were mixed and held for 5 minutes.

Then, hydrogen gas 1 was used as a molecular weight control agent.
After pressurizing 6.5 liters and 3.0 liters of liquid propylene, the reaction system was heated to 70 ° C. After charging 120 mg of the prepolymerization catalyst component obtained above into the reaction system, 1
Polymerization of propylene (first-stage polymerization) was carried out for an hour. After the completion of the polymerization, unreacted propylene and hydrogen gas were purged until the pressure in the container reached 0.2 kg / cm ² · G.

After collecting a small amount of the first-stage polymer, hydrogen gas was introduced into the container. Then, a mixed gas having a molar ratio of propylene and ethylene of 2 was supplied to maintain the pressure inside the container at 6.05 kg / cm ² · G and to carry out propylene-ethylene copolymerization (second stage) at 75 ° C. for 0.4 hours. Polymerization) was performed. After the completion of the polymerization, the unreacted gas contained 0.9 mol% of hydrogen. After purging unreacted gas, a small amount of polymer was collected. After introducing hydrogen gas into the container again,
By supplying a mixed gas with a molar ratio of propylene and ethylene of 0.5, the pressure inside the vessel was kept at 6.02 kg / cm ² · G, and propylene-ethylene copolymerization (third stage polymerization) was carried out at 75 ° C for 0.8 hours. Was carried out to obtain 468 g of a powdery propylene-ethylene block copolymer (BPP1). After the completion of the polymerization, the unreacted gas contained 0.4 mol% of hydrogen.

As a result of analyzing the collected polymer, the obtained propylene-ethylene block copolymer (BPP1) was obtained.
The homopolypropylene portion of the above is 82% by weight, and the low ethylene concentration propylene-ethylene copolymer portion is 6% by weight.
The propylene-ethylene copolymerization portion having a high ethylene concentration was 12% by weight.

In addition, the MFR (2
It was 330 g / 10 minutes at 30 ° C. and a load of 2.16 kg, and the differential scanning calorimetry (7700 Data St) was used.
The heat of fusion (ΔH _m , heating rate 20 ° C./min) determined by cation, Perkin Elma Co., Ltd. is 28.6 cal / min.
g, and the calculated value of the heat of fusion (ΔH _m ') calculated by (24.5 + 1.583 log MFR) is 28.5.
Met.

The ethylene content of the propylene-ethylene copolymerized portion having a low ethylene concentration was 35% by weight, and the ethylene content of the propylene-ethylene copolymerized portion having a high ethylene concentration was 65% by weight. Furthermore, the intrinsic viscosity [η] of the propylene-ethylene copolymerization portion having a low ethylene concentration
_L is 3 dl / g, and high ethylene concentration of propylene-
The intrinsic viscosity [η] _H of the ethylene copolymerized portion was 5 dl / g. Table 2 shows the results.

Production Example 2 Propylene-ethylene block copolymer (BPP2)
Production After prepolymerization under the same conditions as in Production Example 1, the hydrogen gas amount (liter) in the first-stage polymerization, the molar ratio of propylene and ethylene in the second-stage polymerization and the third-stage polymerization, and the pressure in the container (kg / Cm ² · G) and the polymerization time (h) shown in Table 1, main polymerization was carried out under the same conditions as in Production Example 1 to obtain a propylene-ethylene block copolymer (BPP).
2) was obtained. Table 1 shows the hydrogen content (mol%) in the unreacted gas after completion of the second-stage polymerization and the third-stage polymerization.

The ratio of the homopolypropylene portion, the low-ethylene concentration propylene-ethylene copolymer portion and the high-ethylene concentration propylene-ethylene copolymer portion of the obtained propylene-ethylene block copolymer (BPP2),
MFR of homopolypropylene part, ΔH _m and ΔH _m '
And [η] _L and ethylene content of the low ethylene concentration propylene-ethylene copolymerization portion, and [η] _H and ethylene content of the high ethylene concentration propylene-ethylene copolymerization portion were measured in the same manner as in Production Example 1. The results obtained are shown in Table 2.

Production Example 3 Propylene-ethylene block copolymer (BPP3)
Production After prepolymerization under the same conditions as in Production Example 1, the hydrogen gas amount (liter) in the first-stage polymerization, the molar ratio of propylene and ethylene in the second-stage polymerization and the third-stage polymerization, and the pressure in the container (kg / Cm ² · G) and the polymerization time (h) shown in Table 1, main polymerization was carried out under the same conditions as in Production Example 1 to obtain a propylene-ethylene block copolymer (BPP).
3) was obtained. Table 1 shows the hydrogen content (mol%) in the unreacted gas after completion of the second-stage polymerization and the third-stage polymerization.

The ratio of the homopolypropylene portion, the low-ethylene concentration propylene-ethylene copolymer portion and the high-ethylene concentration propylene-ethylene copolymer portion of the obtained propylene-ethylene block copolymer (BPP3),
MFR of homopolypropylene part, ΔH _m and ΔH _m '
And [η] _L and ethylene content of the low ethylene concentration propylene-ethylene copolymerization portion, and [η] _H and ethylene content of the high ethylene concentration propylene-ethylene copolymerization portion were measured in the same manner as in Production Example 1. The results obtained are shown in Table 2.

Production Example 4 Propylene-ethylene block copolymer (BPP4)
After the preliminary polymerization was carried out under the same conditions as in Production Example 1, the amount of hydrogen gas in the first stage polymerization (l), the molar ratio of propylene and ethylene in the second stage polymerization, container pressure (kg / cm ² ·
G) and the polymerization time (h) are shown in Table 1, and the main polymerization was carried out under the same conditions as in Production Example 1 except that the propylene-ethylene copolymerization was one-stage polymerization, and the propylene-ethylene block copolymer ( BPP4) was obtained. The hydrogen content (mol%) in the unreacted gas after the completion of the second stage polymerization is shown in Table 1.

The ratio of the homopolypropylene portion and the propylene-ethylene copolymer portion of the obtained propylene-ethylene block copolymer (BPP4), the MFR of the homopolypropylene portion, ΔH _m and ΔH _m ', and propylene-ethylene. The intrinsic viscosity [η] _H and ethylene content of the copolymerized portion were measured in the same manner as in Production Example 1 and the results are shown in Table 2.

Production Example 5 Propylene-ethylene block copolymer (BPP5)
After the preliminary polymerization was carried out under the same conditions as in Production Example 1, the amount of hydrogen gas in the first stage polymerization (l), the molar ratio of propylene and ethylene in the second stage polymerization, container pressure (kg / cm ² ·
G) and the polymerization time (h) are shown in Table 1, and main polymerization was carried out under the same conditions as in Production Example 1 except that the propylene-ethylene copolymerization portion was one-stage polymerized, to obtain a propylene-ethylene block copolymer. (BPP5) was obtained. The hydrogen content (mol%) in the unreacted gas after the completion of the second stage polymerization is shown in Table 1.

The ratio of the homopolypropylene portion and the propylene-ethylene copolymer portion of the obtained propylene-ethylene block copolymer (BPP5), the MFR of the homopolypropylene portion, ΔH _m and ΔH _m ', and propylene-ethylene. The intrinsic viscosity [η] _{L of the} copolymerized portion and the ethylene content were measured in the same manner as in Production Example 1 and the results are shown in Table 2.

Table 1 Polymerization conditions BPP1 BPP2 BPP3 BPP4 BPP5 First-stage polymerization Hydrogen gas amount (liter) 16.5 11.4 15.0 21.0 13.5 Second-stage polymerization C ₃ / C ₂ ⁽¹⁾ 2.00 2.05 2.00 0.46 1.63 Vessel pressure (kg / cm ² · G) 6.05 6.09 6.05 6.02 6.05 Polymerization time (h) 0.4 0.4 0.4 1.0 1.2 Hydrogen content (mol%) ⁽²⁾ 0.9 0.9 0.09 0.04 0.09 Third stage polymerization C ₃ / C ₂ 0.50 0.54 0.50 ─ ─ Container Internal pressure (kg / cm ² G) 6.02 6.02 6.12 ─ ─ Polymerization time (h) 0.8 0.5 0.8 ─ ─ Hydrogen content (mol%) ⁽³⁾ 0.4 0.4 2.0 ─ ─ Note (1) Mol of propylene and ethylene ratio. (2) Hydrogen content in the unreacted gas after the completion of the second stage polymerization. (3) Hydrogen content in the unreacted gas after the completion of the third stage polymerization.

Table 2 Properties of BPP BPP1 BPP2 BPP3 BPP4 BPP5 Homopolypropylene part Content (% by weight) 82 88 82 82 82 MFR _H (g / 10min) 330 170 270 390 220 220 Heat of fusion (cal / g) Measured value (△ H _m ) 28.6 28.3 28.5 28.7 28.3 Calculated value (△ H _m ') 28.5 28.0 28.3 28.6 28.2 Copolymerized portion ⁽¹⁾ _CL (wt%) ⁽²⁾ 6 5 6 ─ 18 _GL (wt%) ⁽³⁾ 35 35 35 ─ 35 [η] _L (dl / g) 3 3 5 ─ 3 _CH (wt%) ⁽⁴⁾ 12 7 12 18 ─ _GH (wt%) ⁽⁵⁾ 65 65 65 65 ─ [η] _H (dl / g) 55 53 5-MFR _BPP (g / 10min) 60 60 60 60 60 Note (1) Ethylene-propylene copolymer part. (2) The content of the propylene-ethylene copolymerized portion having a low ethylene concentration when the total content of the propylene-ethylene copolymerized portion and the crystalline homopolypropylene portion is 100% by weight. The ratio of (3) The ethylene content of the propylene-ethylene copolymerization portion having a low ethylene concentration. (4) The content of the propylene-ethylene copolymerized portion having a high ethylene concentration when the total content of the propylene-ethylene copolymerized portion and the crystalline homopolypropylene portion is 100% by weight. The ratio of (5) The ethylene content of the propylene-ethylene copolymerization portion having a high ethylene concentration.

Examples 1-6 and Comparative Examples 1-6 1. Raw material (a) Propylene-ethylene block copolymer (BPP1
~ BPP5)

(B) Polyolefin EPR: ethylene-propylene copolymer rubber (EP961SP,
Made by Japan Synthetic Rubber Co., Ltd. MFR = 0.8 g / 10min, ethylene content = 77% by weight. EBR: ethylene-butene copolymer rubber (EBM2011P, manufactured by Nippon Synthetic Rubber Co., Ltd.) MFR = 1 g / 10 min, ethylene content = 80% by weight.

[0083] (c) Talc Talc Average particle size ^{(μm) (1) Ta-} 1 3.3 Ta-2 (2) 3.3 Ta-3 5.2 Note (1) measured by laser diffraction scattering method. (2) Add 100 parts by weight of talc to silazane-modified polysiloxane 1
Surface-treated talc which is a masterbatch of a mixture of 1 part by weight and crystalline homopolypropylene (MFR = 40 g / 10 min) in a weight ratio of 3: 1.

2. Kneading and molding method The above raw materials were blended in the proportions shown in Tables 3 and 4, dry-blended using a super mixer, and then a twin-screw extruder (TEX30 manufactured by Japan Steel Works Ltd.) at 200 ° C. for 30
The mixture was melt-kneaded at a screw rotation speed of 0 rpm and extruded to obtain pellets. By using an injection molding machine, the obtained pellets are
Injection molding at a resin temperature of 200 ° C and a mold temperature of 50 ° C,
Test pieces were prepared.

3. Physical property measurement Physical property measurement of each test piece was performed by the following methods. The results are shown in Tables 3 and 4 below. (1) MFR (g / 10 minutes): Measured according to ASTM D1238 at 230 ° C. and a load of 2.16 kg. (2) Tensile elongation at break (%): Measured at room temperature according to ASTM D638. (3) Flexural modulus (kg / cm ² ): Measured at room temperature according to ASTM D790. (4) Izod impact strength (kgcm / cm): Using ASTM D256, a 3.2 mm thick test piece was used at 23 ° C with a notch and
It was measured at -30 ° C. (5) Rockwell hardness (scale R): Measured by ASTM D785.

Table 3 Example No. 1 2 3 4 Composition (% by weight) (a) BPP BPP1 70 66 64 60 BPP2 ─ ─ ─ (b) Elastomer EPR -7 -7 EBR 10 7 10 7 (c) Talc Ta-1 20 20 ─ ─ Ta- 2 ─ ─ 26 26 Properties of composition MFR (g / 10min) 34 32 35 31 Tensile elongation at break (%) 90 140 100 130 Flexural modulus (kg / cm ² ) 25700 24000 26600 24700 Izod impact strength ⁽¹⁾ 23 ℃ 16 20 14 20 -30 ℃ 3.7 4.1 3.8 4.2 Rockwell hardness (R) 84 80 86 82 Note (1) Unit: kg ・ cm / cm

[0087]

Table 4 Comparative Example No. 1 2 3 4 5 composition (% by weight) (a) BPP BPP1 70 ─ ─ ─ ─ BPP2 ─ 63 ─ ─ ─ BPP3 ─ ─ 66 ─ ─ BPP4 ─ ─ ─ 66 44 BPP5 ─ ─ ─ ─ 22 (b) Elastomer EPR 10 7 7 7 7 EBR ─ 10 7 7 7 (c) Talc Ta-1 20 ─ 20 20 20 Ta-3 ─ 20 ─ ─ ─ Characteristic of composition MFR (g / 10min) 28 35 29 30 33 Tensile elongation at break (%) 60 60 80 40 80 Flexural modulus (kg / cm ² ) 25 100 23100 22400 24300 23800 Izod impact strength ⁽¹⁾ 23 ℃ 14 11 18 9 10 -30 ℃ 4.3 2.7 2.9 3.9 2.8 Rockwell hardness (R) 70 76 76 81 79 Note (1) Unit: kg ・ cm / cm

As is apparent from Tables 3 and 4, Example 1
The thermoplastic resin compositions of to 7 have a large MFR, good moldability, and excellent impact resistance, rigidity, hardness and the like. From the comparison between Example 1 and Comparative Example 1, ethylene-
It can be seen that the hardness is low when the butene copolymer rubber is not blended. From the comparison between Example 5 and Comparative Example 2, it is understood that when the average particle size of talc exceeds 5 μm, the tensile elongation at break and the impact resistance decrease. From the comparison between Example 2 and Comparative Example 3, the intrinsic viscosity [η] _L of the propylene-ethylene copolymerized portion having a low ethylene concentration is higher than the intrinsic viscosity [η] _H of the propylene-ethylene copolymerized portion having a high ethylene concentration. It can be seen that the impact resistance at low temperature decreases as the size increases.
From the comparison between Examples 1 to 7 and Comparative Example 4, in the case of using the propylene-ethylene block copolymer produced by single-stage polymerization containing no low-ethylene concentration propylene-ethylene copolymerization portion, the tensile elongation at break Also, it can be seen that the impact resistance decreases. As is clear from Example 2 and Comparative Example 5, a propylene-ethylene block copolymer containing a low-ethylene concentration propylene-ethylene copolymerization moiety,
Even if a propylene-ethylene block copolymer containing a high-ethylene concentration propylene-ethylene copolymerized portion is blended, sufficient impact resistance cannot be obtained.

[0090]

EFFECT OF THE INVENTION The thermoplastic resin composition of the present invention comprises a homopolypropylene portion having a constant relationship between the heat of fusion and the melt flow rate, a low ethylene concentration propylene-ethylene copolymerization portion, and a high ethylene concentration. Since a propylene-ethylene block copolymer consisting of the propylene-ethylene copolymer part of (1) is produced by multi-step polymerization and a polyolefin elastomer and talc are mixed therein, it is excellent in impact resistance, rigidity and moldability.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Eiji Kuchiki 4-1-1 Tsukiji, Chuo-ku, Tokyo Tonen Kagaku Co., Ltd. (72) Inventor Shinya Kawamura 1 Toyota-cho, Toyota City, Aichi Prefecture In-house (72) Inventor Takesumi Nishio 1 Toyota-cho, Toyota-shi, Aichi Toyota Motor Co., Ltd.

Claims (2)

[Claims] 1. [A] A propylene-ethylene block copolymer obtained by multi-stage polymerization, wherein (a) the melt flow rate (MFR) measured according to ASTM D-1238 is in the range of 100 to 500 g / 10 min. And the heat of fusion (ΔH _m ) obtained from the differential scanning calorimetry and the MFR satisfy the relational expression ΔH _m ≧ 24.5 + 1.583 log MFR.
% By weight, and (b) (i) a low ethylene concentration propylene-ethylene copolymerization portion (ethylene content in the copolymerization portion is 30 to 50% by weight, and intrinsic viscosity is 2 to 5 dl / g). And (ii) propylene-ethylene containing a high ethylene concentration propylene-ethylene copolymerized portion (ethylene content in the copolymerized portion is 50 to 70% by weight, and intrinsic viscosity is 4 to 6 dl / g). 55 to 85 parts by weight of a propylene-ethylene block copolymer composed of a copolymerized portion of 5 to 30% by weight, and [B] (c) MFR of 0.1 to 30 g / 10 min ethylene-butene copolymer rubber 5 to 20 5 to 20 parts by weight of a polyolefin-based elastomer containing, by weight, (d) an MFR of 0.1 to 20 g / 10 minutes, an ethylene-propylene copolymer rubber of 0 to 15 parts by weight, and [C] an average particle diameter of 5 μm or less. Talc 10-25 And a total of 10 parts by weight of the (b) propylene-ethylene copolymerization part and the [B] polyolefin-based elastomer.
The thermoplastic resin composition is characterized in that (i) the propylene-ethylene copolymerized portion having a low ethylene concentration is 10 to 40% by weight based on 0% by weight. 2. The thermoplastic resin composition according to claim 1, wherein the intrinsic viscosity of the propylene-ethylene copolymerization portion having a high ethylene concentration is higher than the intrinsic viscosity of the propylene-ethylene copolymerization portion having a low ethylene concentration. A thermoplastic resin composition having a large size.