JP2001233923A - Propylene/ethylene block copolymer, resin composition and blow-molded body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a propylene/ethylene block copolymer which gives a blow- molded body not only good in heat resistance, rigidity, impact resistance and draw-down resistance but also excellent in the balance particularly between rigidity and low temperature barrier characteristics and to provide a blow- molded body. SOLUTION: The propylene/ethylene block copolymer has an MFR of 0.01-1.0 g and comprises (A) 85-97 wt.% of 25 deg.C xylene-insoluble components and (B) 15-3 wt.% of 25 deg.C xylene-soluble components, where the component (A) has a stereoregularity index of at least 98.0% as measured by 13C-NMR, an intrinsic viscosity of [η] of 2.5-5.5, and a weight-average mol.wt.(Mw) as measured by the GPC method and a content (S) (wt.%) of components having a mol.wt. of 104.5 or less satisfying the relation: S<=-5.3×10-6Mw+7.58, and the component (B) has an ethylene unit content of 30-70 wt.% as measured by 13C-NMR and an intrinsic viscosity [η] of 2.5-9.0.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a propylene-ethylene block copolymer, a method for producing the same, a resin composition, and a blow molded article. More specifically, the present invention relates to a propylene-ethylene block copolymer which has good heat resistance and drawdown resistance, balances rigidity and impact resistance, and particularly has an excellent balance between rigidity and low-temperature barrier properties. A method for efficiently producing the propylene-
The present invention relates to a resin composition containing an ethylene block copolymer, and a blow molded article formed by using the resin composition, which is particularly preferably used for large automobile parts such as bumpers.

[0002]

2. Description of the Related Art Conventionally, polypropylene resins have characteristics such as low specific gravity, high rigidity, good dimensional stability, and excellent heat resistance.
It is molded into a product of a desired shape by various molding methods such as blow molding. Among these molding methods, blow molding has the advantages that the die is inexpensive and the process can be simplified by integral molding. It has been widely used. However, in a general polypropylene resin, the blow molded product has a moldability,
In particular, drawdown resistance, balance between rigidity and impact resistance,
In particular, the balance between rigidity and low-temperature barrier properties has not always been fully satisfactory. Therefore, attempts have been made to improve the above-mentioned disadvantages by a multi-stage polymerization method and the blending of a nucleating agent (Japanese Patent Publication No. 3-74264,
JP-A-63-213547). Particularly in large blow molded articles, polyethylene resin is blended to improve the drawdown resistance, and inorganic fillers such as talc are added to compensate for the decrease in rigidity due to this, which causes an increase in weight. It is the present situation.
The present inventors have previously found a technique for improving rigidity and drawdown resistance of a large blow molded article (WO96 / 02381), but have recently reduced the weight (thinning) of automotive materials and Due to the demand for stability, further improvement in rigidity and impact resistance, particularly improvement in low-temperature barrier properties, has been desired.

[0003]

SUMMARY OF THE INVENTION Under such circumstances, the present invention provides a propylene copolymer which has good heat resistance and drawdown resistance, balances rigidity and impact resistance, and is particularly excellent in low-temperature barrier properties. It is an object of the present invention to provide an ethylene block copolymer, a composition containing the same, and a blow-molded article formed by using the same, which is particularly preferably used for large automobile parts such as bumpers.

[0004]

Means for Solving the Problems The present inventors have made intensive studies to achieve the above object, and as a result, have found that a highly stereoregular propylene-ethylene block copolymer having a specific property, With a resin composition containing an antioxidant and a nucleating agent, the object can be achieved, and the propylene-ethylene block copolymer is a multistage polymerization of propylene and ethylene in the presence of a specific catalyst system. As a result, they have found that they can be obtained efficiently. The present invention has been completed based on such findings.

That is, the present invention relates to (1) a temperature of 230 ° C.
Melt measured under the condition of a load of 2.16 kgf (21.2 N)
Flow rate (MFR) is 0.01 to 1.0 g / 10 minutes
(A) Insoluble components 85 to 9 at 25 ° C. xylene
7% by weight and (B) 15 soluble components in xylene at 25 ° C.
-3% by weight, and the component (A) is (a-
1) Isotopic carbon nuclear magnetic resonance spectroscopy (¹³C-NMR) method
When the stereoregularity index [mmmm] fraction is 98.0% or more
(A-2) Measured in 135 ° C. tetralin
Intrinsic viscosity [η] must be 2.5 to 5.5 deciliter / g
And (a-3) gel permeation chromatography
Weight average molecular weight Mw and molecule determined by the fee (GPC) method
Quantity 10 ^4.5The following component content [S (% by weight)]
(I) S ≦ −5.3 × 10^-6Mw + 7.58 (I) (where Mw is a weight average molecular weight)
And (B) the component (B-1)¹³C-
Ethylene unit content determined by NMR method is 30 to 70 weight
% And (b-2) in 135 ° C. tetralin
The measured intrinsic viscosity [η] is 2.5 to 9.0 deciliter / g
A propylene-ethylene block characterized by being
Copolymer,

(2) (C) A solid formed from (c-1) a magnesium compound, (c-2) a titanium compound, (c-3) an electron donor and optionally a (c-4) silicon compound. The propylene according to (1), wherein propylene and ethylene are subjected to multistage polymerization in the presence of a highly stereoregular catalyst system comprising a catalyst component, (D) an organoaluminum compound, and (E) an electron donating compound. A method for producing an ethylene block copolymer, (3) a resin composition comprising the propylene-ethylene block copolymer of (1), an antioxidant, and a nucleating agent; A) a blow-molded article obtained by molding the propylene-ethylene block copolymer; and (5) a blow-molded article obtained by molding the resin composition of the above (3).

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The propylene-ethylene block copolymer of the present invention has a temperature of 230 ° C. and a load of 2.16 kgf.
(21.2N) melt flow rate (M
FR) should be in the range of 0.01 to 1.0 g / 10 minutes. If the MFR is less than 0.01 g / 10 min, the fluidity is low and the blow moldability is poor. From the viewpoint of blow moldability, a preferable range of the MFR is 0.05 to 1.0 g / 10 minutes. Note that this MF
R is a value measured according to JIS K7210. The propylene-ethylene block copolymer of the present invention is obtained by fractionating a solvent using xylene at 25 ° C.
(A) Insoluble component in xylene at 25 ° C and (B) 25 ° C
It is separated into components soluble in xylene. In the present invention, the amount of the insoluble component in the xylene at 25 ° C. as the component (A) is 85 to 97% by weight, and the component (B) 2
The amount of the soluble component in xylene at 5 ° C is 15 to 3% by weight. When the amount of the component (B) is less than 3% by weight, the impact resistance is poor, and when it exceeds 15% by weight, the rigidity is reduced. From the viewpoint of the balance between impact resistance and rigidity, the amounts of the components (A) and (B) are 87 to 95% by weight and 13%, respectively.
To 5% by weight, especially 88 to 92% by weight and 12%.
~ 8% by weight is preferred.

The components soluble and insoluble in xylene at 25 ° C. were obtained as follows. That is, (1) First, 5 ± 0.05 g of a sample was precisely weighed and placed in a 1000 ml eggplant-shaped flask, and 2,6-di-t-butyl-4-methylphenol (BHT, antioxidant) 1
After adding ± 0.05 g, the rotor and para-xylene 7
Add 00 ± 10 ml. Next, (2) a condenser was attached to the eggplant-shaped flask, and the flask was moved to 120 ± 3 in an oil bath at 140 ± 5 ° C. while operating the rotor.
Heat for 0 minutes to dissolve the sample in para-xylene. Next, (3) After pouring the contents of the flask into a 1000 ml beaker, while stirring the solution in the beaker with a stirrer, allow the solution to cool to room temperature (25 ° C.) (8 hours or more). Filter with wire mesh. (4) The filtrate was further filtered through filter paper, and the filtrate was filtered using methanol 2000 ± 10 in a 3000 ml beaker.
Pour the mixture into 0 ml, and stir the solution at room temperature (25 ° C.) with a stirrer for 2 hours or more. Next, (5) the precipitate is collected by filtration with a wire mesh, air-dried for 5 hours or more, and dried in a vacuum dryer at 100 ± 5 ° C. for 240 to 270 minutes to recover a 25 ° C. xylene-soluble component.

On the other hand, (6) the precipitate collected by a wire mesh in the above (3) is dissolved again in para-xylene according to the above methods (1) and (2), and then the methanol contained in a 3000 ml beaker is dissolved. Transfer quickly and hot to 2000 ± 100 ml, stir with a stirrer for 2 hours or more, and leave overnight at room temperature (25 ° C.). Next, (7) the precipitate is collected by filtration with a wire mesh, air-dried for 5 hours or more, and dried in a vacuum dryer at 100 ± 5 ° C for 240 to 270 minutes to collect a 25 ° C xylene-insoluble component. 25 ° C
The content w (% by weight) of the soluble component with respect to xylene is as follows: where the sample weight is Ag and the weight of the soluble component recovered in (5) is Cg, w (% by weight) = 100 × C / A And the content of the insoluble component is represented by 100-w (% by weight).

In the propylene-ethylene block copolymer of the present invention, the component (A) insoluble in xylene at 25 ° C. and the component (B) soluble in xylene at 25 ° C. must have the following properties. . (A) Insoluble component in xylene at 25 ° C. First, the insoluble component in xylene at 25 ° C. as the component (A) is determined by isotopic carbon nuclear magnetic resonance spectroscopy ( ¹³ C-NMR).
Stereoregularity index [mmmm] fraction obtained by the method is 98.0%
That is all. The component insoluble in xylene at 25 ° C. is mainly composed of a propylene homopolymer component, and the stereoregularity index [mmmm] fraction is also referred to as an isotactic pentad fraction. It shows the ratio of propylene monomer units that are present in the propylene monomer unit and that are continuously connected by five meso bonds. Therefore, the higher the isotactic pentad fraction, the higher the proportion occupied by polypropylene having an isotactic structure. When the stereoregularity index [mmmm] fraction is less than 98.0%, the balance between rigidity and impact resistance and the balance between rigidity and heat resistance are insufficient.

The stereoregularity index is calculated by the following method.
It is a value obtained from the above. That is, xylene at 25 ° C.
Of insoluble components¹³In the C-NMR spectrum, methyl
The carbon signal is from low fields due to stereoregularity
Mmmm, mmmr, rmmr, mm over high magnetic field
rr, mmrm + rrrm, rmrm, rrrr, mr
It is split into nine peaks of rr and mrrm and observed.
Of these nine, mmmm, mmm with strong peak intensity
r, mmrr, mmrm + rrmr, rrrr, mrr
Focusing on the six peaks of m, the stereoregularity of the insoluble component
The target is calculated by the following equation. Stereoregularity index (%) = L_mmmm× 100 / (L_mmmm+ L
_mmmr+ L_mmrr+ L_{mmrm + rrmr}+ L_rrrr+ L_mrrm) Where L_mmmm, L_mmmr, L_mmrr, L_{mmrm + rrmr}, L
_rrrrAnd L_mrrmRespectively¹³For C-NMR spectrum
Mmmm, mmmr, mmrr, mmrm + rr
baseline of mr, rrrr and mrrm peaks
Their height. However, the peak of mmmm is
Composed of multiple discrete points with different heights and peak heights
And the mmmr peak is the text of the main mmmm peak.
The peaks of these peaks
The height from the line is corrected according to an ordinary method.

<Method of Measuring ¹³ C-NMR> A 220 mg sample was collected in an NMR sample tube, and mixed with a 1,2,4-trichlorobenzene / deuterated benzene mixed solvent (volume ratio: 90/1).
0) After adding 3 ml, cap and add
After uniformly dissolving at 0 ° C., ¹³ C-NMR measurement is performed under the following conditions. Apparatus: JNM-EX400 manufactured by JEOL Ltd. Pulse width: 9 μs (45 °) Pulse repetition time: 4 seconds Spectral width: 20000 Hz Measurement temperature: 130 ° C. Number of integrations: 1000 to 10000 times ¹³ C-NMR in the present invention Were all measured by the above method.

The insoluble component in xylene at 25 ° C. has an intrinsic viscosity [η] of 2.5 to 5.5 deciliters / g in 135 ° C. tetralin. If [η] is less than 2.5 deciliters / g, the drawdown resistance is inferior, and if it exceeds 5.5 deciliters / g, the fluidity is low, and the productivity is deteriorated due to the decrease in extrusion characteristics. The intrinsic viscosity [η] is a value measured according to ASTM D1601. Further, the component insoluble in xylene at 25 ° C. has a ratio Mw / Mn (molecular weight distribution) between the weight average molecular weight (Mw) and the number average molecular weight (Mn) determined by gel permeation chromatography (GPC),
It is preferably in the range of 2.0 to 10, especially 3.0 to 8.0.
Is preferably within the range. The weight average molecular weight determined by GPC method Mw and molecular weight ^104.5 ingredient content of less [S (wt%)] having the formula (I) S ≦ -5.3 × 10 -6 Mw + 7.58 ··· ( I) (where Mw is the weight average molecular weight). The molecular weight ^104.5 The following ingredients content of the area occupied by the 10 ^4.5 The following components of GPC curve and A ^*, when the this area occupies the entire GPC curve is A, the following equation S = (A ^* / A) It was determined by × 100. If this relationship is not satisfied, the low molecular weight component will increase with respect to the weight average molecular weight, and the impact resistance, elongation at break, low temperature barrier properties, etc. will decrease.

The GPC measurement conditions are as follows. GPC column: TOSO GMHHR-H (S) HT Solvent: 1,2,4-trichlorobenzene Temperature: 145 ° C. Flow rate: 1.0 ml / min Detector: RI (Waters 150C type) Analysis: HT-GPC ( V1.0) A calibration curve is prepared using standard polystyrene.

[0015] (B) soluble component for 25 ° C. xylene is soluble component The (B) component to 25 ° C. xylene is substantially amorphous component (rubber component), a propylene - ethylene block copolymer Mainly composed of a propylene-ethylene random copolymerized portion. 25 ℃
The component soluble in xylene has an ethylene unit content of 30 to 70% by weight determined by ¹³ C-NMR. If the ethylene unit content is less than 30% by weight, the balance between rigidity and impact resistance, particularly the balance between rigidity and low-temperature barrier properties, will be reduced. If it exceeds 70% by weight, the rigidity may be reduced. In consideration of impact resistance, low-temperature barrier properties, rigidity, etc., the preferred content of this ethylene unit is in the range of 40 to 55% by weight.

The above ethylene unit content is as follows:
It is a value obtained by the method. That is, the sample¹³CN
The MR was measured and 35-21 pp in the spectrum
m [Chemical shift standard for tetramethylsilane (TMS)]
From the seven peak intensities in the region, ethylene (E)
The triene chain fraction (mol%) of pyrene (P) is expressed by the following equation.
Calculate from f_EPE= [K (Tδδ) / T] × 100 f_PPE= [K (Tβδ) / T] × 100 f_EEE= [K (Sγδ) / 4T + K (Sδδ) / 2T]
× 100 f_PPP= [K (Tββ) / T] × 100 f_PEE= [K (Sβδ) / T] × 100 f_PEP= [K (Sββ) / T] × 100 where T = K (Tδδ) + K (Tβδ) + K (Sγ
δ) / 4 + K (Sδδ) / 2 + K (Tββ) + K (Sβ
δ) + K (Sββ) where, for example, F_EPEIs the EPtriad chain fraction (mol
%) And K (Tδδ) is the peak attributed to the Tδδ carbon.
Shows the integrated intensity of Next, the ethylene unit content (weight
%) Is calculated by the following equation using the above triad chain fraction.
I do. Ethylene unit content (% by weight) = 28 / 3f_EEE+2
(F_PEE+ F_EPE) + F _PPE+ F_PEP｝ × 100 / [2
8 ｛3f_EEE+2 (f_PEE+ F_EPE) + F_PPE+
f_PEP｝ +42 ｛3f_PPP+2 (f_PPE+ F_PEP) + F
_EPE+_PEE｝)

The soluble component in xylene at 25 ° C. has an intrinsic viscosity [η] of 2.5 to 9.0 deciliter / g measured in tetralin at 135 ° C. If this [η] is less than 2.5 deciliters / g, the balance between rigidity and impact resistance, particularly the balance between rigidity and low-temperature barrier properties, is reduced. Because of the occurrence of a high portion of the molded article, bumps are generated in the molded product, which may lower the balance between rigidity and impact resistance, particularly the balance between rigidity and low-temperature barrier properties, and may deteriorate the appearance. In consideration of impact resistance, low-temperature barrier properties, appearance of a molded product, and the like, the preferable range of [η] is 3.0 to 7.0 deciliter / g. The intrinsic viscosity [η] is a value measured according to ASTM D1601.

The propylene-ethylene block copolymer of the present invention is a mixture comprising propylene homopolymer and propylene-ethylene random copolymer as main components. Any method can be used as long as the block copolymer can be obtained, and there is no particular limitation. Various methods can be used. According to the method of the present invention described below, a propylene-ethylene block copolymer having desired properties is used. Coalescence can be manufactured efficiently. The method of the present invention comprises the steps of (C) (c
-1) a magnesium compound, (c-2) a titanium compound,
(C-3) An electron donor and optionally used (c-
4) a solid catalyst component formed from a silicon compound;
This is a method in which propylene and ethylene are subjected to multistage polymerization in the presence of a highly stereoregular catalyst system comprising (D) an organoaluminum compound and (E) an electron donating compound.

In the above highly stereoregular catalyst system, (C)
Examples of the magnesium compound of the component (c-1) used for forming the solid catalyst component include, for example, a general formula (II) MgR ¹ R ² ... (II) (wherein, R ¹ and R ² are each a halogen atom , A hydrocarbon group or an OR group (R is a hydrocarbon group), which may be the same or different.). In the general formula (II), the halogen atom among R ¹ and R ² is
Chlorine, bromine, iodine and fluorine atoms. Examples of the hydrocarbon group of R ¹ and R ² and the hydrocarbon group represented by R include an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 5 to 12 carbon atoms, and a hydrocarbon group having 6 to 1 carbon atoms.
And an aralkyl group having 7 to 12 carbon atoms.

Examples of such a magnesium compound include alkyl magnesium, aryl magnesium, dimethoxy magnesium, dibutyl magnesium, dibutyl magnesium, dihexyl magnesium, dioctyl magnesium, butyl ethyl magnesium, diphenyl magnesium and dicyclohexyl magnesium, and dimethoxy magnesium. , Diethoxymagnesium, dibutoxymagnesium, dihexoxymagnesium, dioctoxymagnesium, diphenoxymagnesium, dicyclohexoxymagnesium, etc., alkoxymagnesium, aryloxymagnesium, ethylmagnesium chloride, butylmagnesium chloride, hexylmagnesium chloride, isobutylmagnesium Chloride, tert-butylmagnesium chloride, phenylmagnesium chloride, benzylmagnesium chloride, ethylmagnesium bromide, butylmagnesium bromide, alkylmagnesium halides such as phenylmagnesium bromide, butylmagnesium iodide, arylmagnesium halides, butoxymagnesium chloride, cyclohexoxymagnesium chloride Magnesium chloride, phenoxymagnesium chloride, ethoxymagnesium bromide, butoxymagnesium bromide, ethoxymagnesium iodide, and other alkoxymagnesium halides, aryloxymagnesium halides, magnesium chloride, magnesium bromide,
Examples thereof include magnesium halide such as magnesium iodide. Among these magnesium compounds, magnesium halide, alkoxymagnesium, alkylmagnesium, and alkylmagnesium halide are preferred from the viewpoint of polymerization activity and stereoregularity.

The above-mentioned magnesium compound can be prepared from metallic magnesium or another magnesium compound when preparing the component (C). As an example of such a method, a metal halide is added to a metal magnesium and a general formula (III) X _n M (OR ³ ) _mn ... (III) (where X is a hydrogen atom, a halogen atom or a carbon atom having 1 to 1 carbon atoms). 2
A hydrocarbon group of 0, M is a boron, carbon, aluminum, silicon or phosphorus atom, R ³ is a hydrocarbon group having 1 to 20 carbon atoms, m is a valence of M, and n is an integer of 0 to less than m.
When X is a plurality, each X may be the same or different, and if the OR ³ there are a plurality, each OR ³ may be the same or different. A) contacting an alkoxy-containing compound represented by the formula (1). In the above general formula (III), X represents a hydrocarbon group having 1 to 20 carbon atoms and R ³
Examples of the hydrocarbon group having 1 to 20 carbon atoms represented by are those having 1 to 20 carbon atoms such as methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, hexyl group and octyl group. C6 to C20 such as an alkyl group, a cycloalkyl group having 5 to 20 carbon atoms such as a cyclohexyl group, an allyl group, a propenyl group, a butenyl group and the like; And an aralkyl group having 7 to 20 carbon atoms such as an aryl group of 20 to 20, a benzyl group, a phenethyl group, and a 3-phenylpropyl group. Among them, an alkyl group having 1 to 10 carbon atoms is particularly preferable.

Another example is the general formula (IV) Mg (OR ⁴ ) ₂ ... (IV) wherein R ⁴ is a hydrocarbon group having 1 to 20 carbon atoms,
One of the OR ⁴ may be the same or different. A) contacting a halide with the magnesium alkoxy compound represented by the formula (1). In the above general formula (IV),
As the hydrocarbon group having 1 to 20 carbon atoms represented by R ⁴ ,
For example, an alkyl group having 1 to 20 carbon atoms such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a hexyl group, and an octyl group; C2-C2 such as alkyl group, allyl group, propenyl group and butenyl group
0 to 6 carbon atoms such as an alkenyl group, a phenyl group, a tolyl group, and a xylyl group;
And an aralkyl group of 0. Among them, an alkyl group having 1 to 10 carbon atoms is particularly preferable. Examples of halides in these methods include silicon tetrachloride,
Examples thereof include silicon tetrabromide, tin tetrachloride, tin tetrabromide, and hydrogen chloride. Of these, silicon tetrachloride is particularly preferable. The magnesium compound of the component (c-1) may be used alone or in combination of two or more kinds, and may be used by being supported on a support such as silica, alumina, or polystyrene. May be used as a mixture with a halogen compound or the like.

In the present invention, the titanium compound of the component (c-2) used for forming the solid catalyst component is not particularly limited, but is represented by the general formula (V) TiX ¹ _p (OR ⁵ ) _4-p (V) are preferred. In the general formula (V), X ¹ represents a halogen atom, among which a chlorine atom and a bromine atom are preferable, and a chlorine atom is particularly preferable. R ⁵ represents a hydrocarbon group, which may be saturated, unsaturated, linear, branched, or cyclic, and further contains a hetero atom such as sulfur, nitrogen, oxygen, silicon, and phosphorus. There may be. R ⁵ is preferably a hydrocarbon group having 1 to 10 carbon atoms, specifically, an alkyl group, an alkenyl group, a cycloalkyl group, a cycloalkenyl group, an aryl group and an aralkyl group.
Particularly, a linear or branched alkyl group is preferable. −
If OR ⁵ there are a plurality, they may be the same or different from each other. Specific examples of R ⁵ include a methyl group,
Ethyl, propyl, isopropyl, butyl, isobutyl, pentyl, hexyl, heptyl, octyl, decyl, allyl, butenyl, cyclopentyl, cyclohexyl, cyclohexenyl, phenyl, Examples include a tolyl group, a benzyl group, and a phenethyl group. p shows the integer of 0-4.

Examples of the titanium compound represented by the general formula (V) include tetramethoxytitanium, tetraethoxytitanium, tetra-n-propoxytitanium, tetraisopropoxytitanium, tetra-n-butoxytitanium, and tetraisobutoxytitanium. Tetraalkoxytitanium such as titanium, tetracyclohexyloxytitanium, and tetraphenoxytitanium; titanium tetrachloride such as titanium tetrachloride, titanium tetrabromide, and titanium tetraiodide; methoxytitanium trichloride; ethoxytitanium trichloride; propoxytitanium trichloride , N-butoxytitanium trichloride, propoxytitanium trichloride, n-
Dihalogenated monoalkoxytitanium such as butoxytitanium trichloride and ethoxytitanium tribromide, dimethoxytitanium dichloride, diethoxytitanium dichloride, dipropoxytitanium dichloride, dihalogenated dihalide such as di-n-butoxytitanium dichloride and diethoxytitanium dibromide Monohalogenated trialkoxytitaniums such as alkoxytitanium, trimethoxytitanium chloride, triethoxytitanium chloride, tripropoxytitanium chloride, tri-n-butoxytitanium chloride and the like are mentioned. Among these, titanium compounds containing a high halogen, especially Titanium tetrachloride is preferred. Further, these titanium compounds may be used alone or in combination of two or more.

In the present invention, examples of the electron donor of the component (c-3) used for forming the solid catalyst component include alcohols, phenols, ketones, aldehydes, organic acids, and organic acids and inorganic acids. Acid esters,
Oxygen-containing electron donors such as ethers such as monoether, diether, and polyether, ammonia, amines,
Examples thereof include nitrogen-containing electron donors such as nitriles and isocyanates. Of these, ester compounds of polycarboxylic acids, particularly monoesters and / or diester derivatives of aromatic dicarboxylic acids are preferred. Here, the monoester and / or diester derivative of the aromatic dicarboxylic acid is preferably one in which the organic group in the ester portion is a linear, branched, or cyclic aliphatic hydrocarbon group. Such substances include, for example, phthalic acid, naphthalene-1,2-dicarboxylic acid, naphthalene-2,3-dicarboxylic acid, 5,
6,7,8-tetrahydronaphthalene-1,2-dicarboxylic acid, 5,6,7,8-tetrahydronaphthalene-
Methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, t-butyl, n-pentyl such as 2,3-dicarboxylic acid, indane-4,5-dicarboxylic acid, indane-5,6-dicarboxylic acid, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 1,1-dimethylpropyl, 1-methylpentyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl, 1-
Ethylbutyl, 2-ethylbutyl, 3-ethylbutyl,
n-hexyl, cyclohexyl, n-heptyl, n-octyl, n-nonyl, 2-methylhexyl, 3-methylhexyl, 4-methylhexyl, 2-ethylhexyl,
3-ethylhexyl, 4-ethylhexyl, 2-methylpentyl, 3-methylpentyl, 2-ethylpentyl,
Examples include dialkyl esters such as 3-ethylpentyl. Among these, phthalic acid diester derivatives are particularly preferable, and specific examples thereof include di-n-butyl phthalate, diisobutyl phthalate, and di-n-heptyl phthalate. The electron donor of the component (c-3) may be used alone, or two or more kinds may be used in combination.

[0026] In the present invention, the silicon compound (c-4) component used as necessary for the formation of the solid catalyst component, for example, the general formula ^{(VI) Si (OR 6)} q X 2 4-q ··· ( VI) A compound represented by the following formula: By using such a silicon compound, it is possible to improve the catalytic activity and stereoregularity and to reduce the amount of fine powder in the produced polymer. In the above general formula (VI), X ²
Represents a halogen atom, among which a chlorine atom and a bromine atom are preferable, and a chlorine atom is particularly preferable. R ⁶ represents a hydrocarbon group, which may be saturated, unsaturated, linear, branched, or cyclic, and further contains a hetero atom such as sulfur, nitrogen, oxygen, silicon, and phosphorus. There may be. R ⁶ is preferably a hydrocarbon group having 1 to 10 carbon atoms, specifically, an alkyl group, an alkenyl group, a cycloalkyl group, a cycloalkenyl group, an aryl group and an aralkyl group. If the -OR ⁶ there is more than one,
They may be the same or different from each other. Specific examples of R ⁶ include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, pentyl, hexyl, heptyl, octyl, decyl, allyl, butenyl, and cyclopentyl. , Cyclohexyl, cyclohexenyl, phenyl, tolyl, benzyl, phenethyl and the like. q shows the integer of 0-3. Specific examples of the silicon compound represented by the general formula (VI) include silicon tetrachloride, methoxytrichlorosilane, dimethoxydichlorosilane, trimethoxychlorosilane, ethoxytrichlorosilane, diethoxydichlorosilane, triethoxychlorosilane, propoxytrichlorosilane, Examples thereof include dipropoxydichlorosilane and tripropoxychlorosilane. Among these, silicon tetrachloride is particularly preferred. These silicon compounds may be used alone or in combination of two or more.

In the highly stereoregular catalyst system according to the present invention, the organoaluminum compound used as the component (D) is not particularly limited. Preferred examples are given. Examples of the organoaluminum compound include trialkylaluminums such as trimethylaluminum, triethylaluminum, triisopropylaluminum, triisobutylaluminum, trioctylaluminum, diethylaluminum monochloride, diisopropylaluminum monochloride, diisobutylaluminum monochloride, dioctylaluminum monochloride. Dialkylaluminum monohalides such as chloride, alkylaluminum sesquihalides such as ethylaluminum sesquichloride,
A chain aluminoxane such as methylaluminoxane is exemplified. Among them, trialkyl aluminum having a lower alkyl group having 1 to 5 carbon atoms, particularly trimethyl aluminum, triethyl aluminum, tripropyl aluminum and triisobutyl aluminum are preferred. The organoaluminum compound of the component (D) may be used alone or in combination of two or more.

Further, in the highly stereoregular catalyst system,
As the electron donating compound used as the component (E), for example, an organosilicon compound represented by the general formula (VII) SiR ⁷ _a (OR ⁸ ) _4-a (VII) can be preferably exemplified. In the general formula (VII), R ⁷ has 1 to 2 carbon atoms.
0 represents a hydrocarbon group, which may be linear, branched or cyclic, such as an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an aryl group, and an aralkyl group. And the like,
R ⁸ represents a hydrocarbon group having 1 to 4 carbon atoms, and the hydrocarbon group may be linear or branched, and examples thereof include a methyl group, an ethyl group, an n-propyl group, and an isopropyl group. No. a represents an integer of 1 to 3, and when there are a plurality of R ⁷ , each R ⁷ may be the same or different from each other, and may be bonded to each other to form a ring structure. If -OR ⁸ there are a plurality, each -OR ⁸ may be the same or different from each other.

Examples of the organosilicon compound represented by the general formula (VII) include methyltrimethoxysilane, ethyltrimethoxysilane, propyltrimethoxysilane, isopropyltrimethoxysilane, butyltrimethoxysilane, and isobutyltrimethoxysilane. , T-butyltrimethoxysilane, texyltrimethoxysilane, methyltriethoxysilane, ethyltriethoxysilane, propyltriethoxysilane, isopropyltriethoxysilane, butyltriethoxysilane, isobutyltriethoxysilane, t-butyltriethoxysilane , Texyltriethoxysilane, propyltripropoxysilane,
Dimethyldimethoxysilane, diethyldimethoxysilane, dipropyldimethoxysilane, diisopropyldimethoxysilane, cybutyldimethoxysilane, diisobutyldimethoxysilane, di-t-butyldimethoxysilane, ethylmethyldimethoxysilane, t-butylmethyldimethoxysilane, trimethylmethoxysilane, Alkylalkoxysilanes such as triethylmethoxysilane, tripropylmethoxysilane, triisopropylmethoxysilane and tributylmethoxysilane, cyclopentyltrimethoxysilane, cyclopentyltriethoxysilane, cyclohexyltrimethoxysilane, cycloalkyl such as dicyclopentyldimethoxysilane and dicyclohexyldimethoxysilane Alkoxysilane, phenyltrimethoxysilane, E sulfonyl triethoxysilane, can be mentioned phenylalkyl alkoxysilane, such as diphenyldimethoxysilane. Also, cyclopentylmethyldimethoxysilane, cyclohexylmethyldimethoxysilane, t-butylcyclopentyldimethoxysilane, t-butylcyclohexyldimethoxysilane,
Cyclohexylcyclopentyldimethoxysilane, 1,
1-dimethoxy-2,6-dimethyl-1-silacyclohexane and the like can also be mentioned.

[0030] In particular, preferred organic silicon compounds of the general formula _{^{(VIII) SiR 9 2 (OR}} 10) can be exemplified compounds represented by ₂ ··· (VIII). In the general formula (VIII), R ⁹ represents a branched chain hydrocarbon group or a saturated cyclic hydrocarbon group having 1 to 20 carbon atoms, preferably a tertiary alkyl group or cycloalkyl group having 1 to 20 carbon atoms. No. R ¹⁰ represents a linear or branched hydrocarbon group having 1 to 4 carbon atoms, preferably a methyl group, an ethyl group,
Examples include an n-propyl group and an isopropyl group. 2
Two R ^{9 s} may be the same or different from each other, may combine with each other to form a ring structure,
R ¹⁰ may be the same or different. Examples of the organosilicon compound represented by the above general formula (VIII) include:
Dicyclopentyldimethoxysilane, dicyclohexyldimethoxysilane, di-t-butyldimethoxysilane,
t-butylcyclopentyldimethoxysilane, t-butylcyclohexyldimethoxysilane, cyclopentyltexyldimethoxysilane, cyclohexyltexyldimethoxysilane, cyclohexylcyclopentyldimethoxysilane, dicyclopentyldiethoxysilane, dicyclohexyldiethoxysilane, di-t-butyldiethoxysilane , T-butylcyclopentyldiethoxysilane, t-butylcyclohexyldiethoxysilane, cyclopentyltexyldiethoxysilane, cyclohexyltexyldiethoxysilane, cyclohexylcyclopentyldiethoxysilane, 1,1-dimethoxy-2,6-
Dimethyl-1-silacyclohexane and the like can be mentioned.

In the present invention, one kind of the electron donating compound (E) may be used alone, or two or more kinds thereof may be used in combination. As a method for preparing the solid catalyst component which is the component (C) in the highly stereoregular catalyst system used in the present invention, the above-mentioned (c-1) magnesium compound, (c-
2) The titanium compound, (c-3) the electron donor, and the (c-4) silicon compound used as necessary may be brought into contact by a usual method, and the contact procedure is not particularly limited. For example, each component may be contacted in the presence of an inert solvent such as a hydrocarbon, or each component may be contacted after being diluted with an inert solvent such as a hydrocarbon. Examples of the inert solvent include aliphatic hydrocarbons such as octane, decane, and ethylcyclohexane, alicyclic hydrocarbons, and mixtures thereof.

Here, the titanium compound is usually used in an amount of 0.5 to 1 mol of magnesium of the above magnesium compound.
-100 mol, preferably 1-50 mol. If the molar ratio is outside the above range, the catalytic activity may be insufficient. In addition, the above-mentioned electron donor is usually used for 1 mol of magnesium of the above-mentioned magnesium compound.
It is used in an amount of 0.01 to 10 mol, preferably 0.05 to 1.0 mol. If the molar ratio deviates from the above range, catalytic activity and stereoregularity may be insufficient. Further, when a silicon compound is used, usually 0.001 to 100 mol, relative to 1 mol of magnesium of the above magnesium compound,
Preferably, 0.005 to 5.0 moles are used. If the molar ratio deviates from the above range, the effect of improving catalytic activity and stereoregularity may not be sufficiently exhibited, and the amount of fine powder in the produced polymer may increase.

The contact of the above components (c-1) to (c-4) is performed at a temperature of 100 to 150 ° C., preferably 105 to 140 ° C., after adding all the components. If the contact temperature is outside the above range, the effect of improving the catalytic activity and stereoregularity will not be sufficiently exhibited. The contact is usually performed for 1 minute to 24 hours, preferably for 10 minutes to 6 hours. The range of the pressure at this time varies depending on the type of solvent, the contact temperature, etc. when a solvent is used.
G, preferably in the range of 0 to 1 MPa · G. In addition, during the contact operation, it is preferable to perform stirring in view of uniformity of contact and contact efficiency.

Further, it is preferable that the contact with the titanium compound is carried out twice or more so that the titanium compound is sufficiently supported on the magnesium compound serving as a catalyst carrier. When a solvent is used in the contacting operation, it is usually 5000 ml or less, preferably 10 to 1 mol per mol of the titanium compound.
Use 000 ml of solvent. If this ratio deviates from the above range, contact uniformity and contact efficiency may deteriorate. The solid catalyst component obtained by the above contact is usually 1
It is preferable to wash with an inert solvent at a temperature of 00 to 150 ° C, preferably 120 to 140 ° C. When the washing temperature is outside the above range, the effect of improving the catalytic activity and stereoregularity is not sufficiently exhibited. Examples of the inert solvent include, for example, aliphatic hydrocarbons such as octane and decane, alicyclic hydrocarbons such as methylcyclohexane and ethylcyclohexane, aromatic hydrocarbons such as toluene and xylene, tetrachloroethane, and chlorofluorocarbons. Halogenated hydrocarbons or mixtures thereof. Of these, aliphatic hydrocarbons are preferably used.

The washing method is not particularly limited, but a method such as decantation and filtration is preferred. There are no particular restrictions on the amount of the inert solvent used, the washing time, and the number of washings.
100 to 100000 ml, preferably 100
Use 0-50000 ml of solvent, usually 1
The reaction is performed for a period of from minutes to 24 hours, preferably from 10 minutes to 6 hours.
If the ratio deviates from the above range, the cleaning may be incomplete.

The range of the pressure at this time varies depending on the type of the solvent, the washing temperature, and the like.
a · G, preferably in the range of 0 to 1 MPa · G. In addition, during the washing operation, it is preferable to perform stirring from the viewpoint of uniformity of washing and efficiency of washing. In addition, washing is preferably repeated 5 times or more to be effective. The obtained solid catalyst component can be stored in a dry state or in an inert solvent such as a hydrocarbon. The amount of the catalyst component used in the polymerization is not particularly limited, but the solid catalyst component of the component (C) is converted to titanium atoms and has a reaction volume of 1%.
The amount is usually in the range of 0.0005 to 1 mmol per liter, and the organoaluminum compound (D) has an aluminum / titanium atomic ratio of usually 1 to 1.
An amount is used such that it is in the range of 1000, preferably 10-500. If the atomic ratio is outside the above range, the catalytic activity may be insufficient. Further, the electron donating compound of the component (E) has an electron donating compound / organoaluminum compound molar ratio of usually 0.001 to 5.0, preferably
An amount is used such that it is in the range of 0.01 to 2.0, more preferably 0.05 to 1.0. If the molar ratio is outside the above range, sufficient catalytic activity and stereoregularity may not be obtained. However, when pre-polymerization is performed, it can be further reduced.

In the block copolymerization of propylene and ethylene in the present invention, first of all, propylene is preliminarily polymerized, and then main polymerization is carried out, if desired, in view of polymerization activity, stereoregularity and polymer powder form. Is also good.
In this case, propylene is usually added at a temperature of 1 to 100 ° C. in the presence of a catalyst obtained by mixing (C) the solid catalyst component, (D) the organoaluminum compound, and (E) the electron donating compound at a predetermined ratio. The prepolymerization is carried out at a temperature in the range from normal pressure to a pressure of about 5 MPa · G, and then the main polymerization is carried out in the presence of the components (D) and (E) and the prepolymerized product. In the method for producing a propylene-ethylene block copolymer of the present invention, the highly stereoregular catalyst system prepared as described above, or the component (D),
Propylene and ethylene are subjected to multistage polymerization in the presence of the component (E) and the prepolymerized product. In the latter case using the prepolymerized product, the prepolymerized product and (D),
The component (E) forms a highly stereoregular catalyst system.

In this multistage polymerization, a method in which a propylene homopolymer is produced in the first stage and a propylene-ethylene random copolymer is produced in the second stage is preferred. Further, each stage of polymerization may be carried out in two or more stages of multistage polymerization, and a method in which the production of the propylene homopolymer in the former stage is carried out in two or more stages of multistage polymerization is particularly preferable. In this case, the polymerization may be performed in a batch system of two or more stages in one polymerization tank, or may be performed in a continuous system using two or more polymerization tanks.

As the polymerization system, any system such as gas phase polymerization, slurry polymerization, bulk polymerization, and solution polymerization can be employed. Further, two or more kinds, such as slurry polymerization and gas phase polymerization, and bulk polymerization and gas phase polymerization, may be used in combination. Regarding the polymerization conditions, when the propylene homopolymer is produced in the former polymerization step, the above-mentioned catalyst system is used, and
Temperature of about 00 ° C., preferably in the range of 30 to 100 ° C. and atmospheric pressure of about 10 MPa · G, preferably 0.2 to 7 M
The polymerization is carried out at a pressure in the range of Pa · G while introducing propylene. In addition, a molecular weight regulator such as hydrogen can be added to regulate the molecular weight. Further, a catalyst which has been preliminarily polymerized with an α-olefin such as ethylene, propylene, 1-butene, or 1-hexene may be used as a catalyst at the time of polymerization. And when producing a propylene-ethylene random copolymer in a subsequent polymerization stage,
In the presence of the catalyst-containing propylene homopolymer obtained in the previous step, propylene and ethylene are copolymerized. The propylene-ethylene copolymerization is usually carried out subsequent to the propylene polymerization in the previous stage. The polymerization temperature is preferably in the range of 0 to 200C, more preferably 30 to 100C. The polymerization pressure is usually from atmospheric pressure to 10 MPa · G,
It is preferably in the range of 0.2 to 7 MPa · G, and the polymerization is carried out while introducing a mixed gas of propylene and ethylene.
Further, a molecular weight regulator such as hydrogen can be added to regulate the molecular weight of the propylene-ethylene random copolymer.

The content of ethylene units in the propylene-ethylene random copolymer can be adjusted by the mixing ratio of the mixed gas of propylene and ethylene introduced. Further, the copolymerization ratio of the propylene-ethylene random copolymer can be adjusted by the polymerization time and the polymerization pressure. FIG. 1 is a flowchart showing an example of the method for producing a propylene-ethylene block copolymer of the present invention. The propylene-ethylene block copolymer of the present invention thus obtained has good heat resistance, good drawdown resistance, and excellent balance between rigidity and impact resistance, and particularly balance between rigidity and low-temperature barrier properties. An excellent large blow molded article can be provided.

The propylene-ethylene block copolymer of the present invention comprises a propylene homopolymer and a propylene-
An ethylene random copolymer may be blended so as to obtain the above-mentioned properties. Next, the resin composition of the present invention contains the above-mentioned propylene-ethylene block copolymer of the present invention, an antioxidant and a nucleating agent as essential components. Preferable examples of the antioxidant include a phenolic antioxidant and a phosphorus-based antioxidant.

As phenolic antioxidants, conventionally known ones, for example, 2,6-di-t-butyl-4-methylphenol, 2,6-di-t-butyl-4-ethylphenol, 2,6 -Dicyclohexyl-4-methylphenol, 2,6-diisopropyl-4-ethylphenol, 2,6-di-t-amyl-4-methylphenol,
2,6-di-tert-octyl-4-n-propylphenol, 2,6-dicyclohexyl-4-n-octylphenol, 2-isopropyl-4-methyl-6-tert-butylphenol, 2-tert-butyl-2 -Ethyl-6-t-
Octylphenol, 2-isobutyl-4-ethyl-6
-T-hexylphenol, 2-cyclohexyl-4-
n-butyl-6-isopropylphenol, dl-α-
Tocopherol, t-butylhydroquinone, 2,2'-
Methylenebis (4-methyl-6-t-butylphenol), 4,4'-butylidenebis (3-methyl-6-t
-Butylphenol), 4,4'-thiobis (3-methyl-6-t-butylphenol), 2,2'-thiobis (4-methyl-6-t-butylphenol), 4,4 '
-Methylenebis (2,6-di-t-butylphenol), 2,2′-methylenebis [6- (1-methylcyclohexyl) -p-cresol], 2,2′-ethylidenebis (2,4-di-t -Butylphenol), 2,
2'-butylidenebis (2-t-butyl-4-methylphenol), 1,1,3-tris (2-methyl-4-hydroxy-5-t-butylphenyl) butane, triethylene glycol-bis [3- (3-t-butyl-5-methyl-4-hydroxyphenyl) propionate],
1,6-hexanediol-bis [3- (3,5-di-
t-butyl-4-hydroxyphenyl) propionate], 2,2-thiodiethylenebis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], N, N'-hexamethylenebis ( 3,5-di-t
-Butyl-4-hydroxy-hydrocinnamide), 3,
5-di-t-butyl-4-hydroxybenzylphosphonate-diethyl ester, 1,3,5-tris (2,6
-Dimethyl-3-hydroxy-4-t-butylbenzyl) isocyanurate, 1,3,5-tris [(3,5
-Di-t-butyl-4-hydroxyphenyl) propionyloxyethyl] isocyanurate, tris (4-t
-Butyl-2,6-dimethyl-3-hydroxybenzyl) isocyanurate, 2,4-bis (n-octylthio) -6- (4-hydroxy-3,5-di-t-butylanilino) -1,3,3 5-triazine, tetrakis [methylene-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] methane, bis (3,5-
Ethyl di-tert-butyl-4-hydroxybenzylphosphonate) calcium, bis (3,5-di-tert-butyl-4)
-Hydroxybenzylphosphonate) nickel, bis [3,3-bis (3-t-butyl-4-hydroxyphenyl) ptylic acid] glycol ester, N,
N'-bis [(3,5-di-tert-butyl-4-hydroxyphenyl) propionyl] hydrazine, 2,2'-oxamidamidebis [ethyl-3- (3,5-di-tert-butyl-4-hydroxy) Phenyl) propionate], 2,
2'-methylenebis (4-methyl-6-t-butylphenol) terephthalate, 1,3,5-trimethyl-
2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, 3,9-bis [1,1-
Dimethyl-2- {β- (3-t-butyl-4-hydroxy-5-methylphenyl) propionyloxy} ethyl] 2,4,8-10-tetraoxaspiro [5,5]
Undecane, 2,2-bis [4- (2- (3,5-di-
t-butyl-4-hydroxyhydrocinnamoyloxy)) ethoxyphenyl] propane, β- (3,5-di-tert-butyl-4-hydroxyphenyl) propionic acid alkyl ester, n-octadecyl β- (4-hydroxy -3,5-di-t-butylphenyl) propionate, butylated hydroxytoluene, and the like.

Among these, the compounds preferably used are 2,6-di-t-butyl-4-methylphenol, triethylene glycol-bis [3- (3-t-
Butyl-5-methyl-4-hydroxyphenyl) propionate], 1,6-hexanediol-bis [3-
(3,5-di-t-butyl-4-hydroxyphenyl)
Propionate], 2,2-thiodiethylenebis [3-
(3,5-di-t-butyl-4-hydroxyphenyl)
Propionate], N, N'-hexamethylenebis (3,5-di-t-butyl-4-hydroxy-hydrocinnamide), 3,5-di-t-butyl-4-hydroxybenzylphosphonate-diethyl ester, 3,5
-Tris (2,6-dimethyl-3-hydroxy-4-t
-Butylbenzyl) isocyanurate, 1,3,5-tris [(3,5-di-t-butyl-4-hydroxyphenyl) propionyloxyethyl] isocyanurate,
Tris (4-t-butyl-2,6-dimethyl-3-hydroxybenzyl) isocyanurate, 2,4-bis (n
-Octylthio) -6- (4-hydroxy-3,5-di-t-butylanilino) -1,3,5-triazine, tetrakis [methylene-3- (3,5-di-t-butyl-
4-hydroxyphenyl) propionate] methane, bis (3,5-di-t-butyl-4-hydroxybenzylphosphonate ethyl) calcium, bis (3,5-di-t
-Butyl-4-hydroxybenzylphosphonate)
Nickel, bis [3,3-bis (3-t-butyl-4-
[Hydroxyphenyl) butyric acid] glycol ester, N, N'-bis [(3,5-di-t-butyl-
4-hydroxyphenyl) propionyl] hydrazine,
2,2'-Ogizamide bis [ethyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 2,2'-methylenebis (4-methyl-6-t-
Butylphenol) terephthalate, 1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, 3,9-bis [1,1-dimethyl-2 -｛Β- (3-t-butyl-4
-Hydroxy-5-methylphenyl) propionyloxydiethyl] -2,4,8,10-tetraoxaspiro [5,5] undecane, 2,2-bis [4- (2-
(3,5-di-t-butyl-4-hydroxyhydrocinnamoyloxy)) ethoxyphenyl] propane, β-
(3,5-di-t-butyl-4-hydroxyphenyl)
Propionic acid alkyl ester, n-octadecyl β-
(4-hydroxy-3,5-di-t-butylphenyl)
And propionate and butylated hydroxytoluene.

The above β- (3,5-di-tert-butyl-4-)
As the alkyl ester of (hydroxyphenyl) propionic acid, an alkyl ester having 18 or less carbon atoms is particularly preferable. Further, in the present invention, particularly preferably used phenolic antioxidants include 2,6-di-t-
Butyl-4-methylphenol, tetrakis [methylene-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] methane, bis (3,5-di-t
-Butyl-4-hydroxybenzylphosphonate)
Calcium, ethyl bis (3,5-di-t-butyl-4-hydroxybenzylphosphonate) nickel, bis [3,5-bis (4-hydroxy-3-t-butylphenyl) butyric acid] glycol ester, N,
N'-bis [(3,5-di-tert-butyl-4-hydroxyphenyl) propionyl] hydrazine, 2,2'-oxazamidebis [ethyl-3- (3,5-di-tert-butyl-4-hydroxy) Phenyl) propionate], 2,
2'-methylenebis (4-methyl-6-t-butylphenol) terephthalate, 1,3,5-trimethyl-
2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, 3,9-bis [1,1-
Dimethyl-2- {β- (3-t-butyl-4-hydroxy-5-methylphenyl) propionyloxy} ethyl] -2,4,8,10-tetraoxaspiro [5,
5] undecane, 1,3,5-tris [(3,5-di-
t-butyl-4-hydroxyphenyl) propionyloxyethyl] isocyanurate, 2,2-bis [4-
(2- (3,5-di-tert-butyl-4-hydroxyhydrocinnamoyloxy)) ethoxyphenyl] propane, n-octadecyl β- (4-hydroxy-3,5-
(Di-t-butylphenyl) propionate, butylated hydroxytoluene, and the like.

As the phosphorus-based antioxidant, conventionally known ones, for example, trioctyl phosphite, trilauryl phosphite, tridecyl phosphite, octyl
-Diphenylphosphite, tris (2,4-di-t-
(Butylphenyl) phosphite, triphenylphosphite, tris (butoxyethyl) phosphite, tris (nonylphenyl) phosphite, distearylpentaerythritol diphosphite, tetra (tridecyl)
-1,1,3-tris (2-methyl-5-t-butyl-
4-hydroxyphenyl) butane diphosphite, tetra (C ₁₂ -C ₁₅ mixed alkyl) -4,4'-isopropylidene diphenyl diphosphite, tetra (tridecyl) -4,4'-butylidene bis (3-methyl - 6-t
-Butylphenol) diphosphite, tris (3,5
-Di-t-butyl-4-hydroxyphenyl) phosphite, tris (mono / di-mixed nonylphenyl) phosphite, hydrogenated-4,4'-isopropylidene diphenol polyphosphite, bis (octylphenyl) bis [4,4'-butylidenebis (3-methyl-6-t-butylphenol)] • 1,6-hexanediol diphosphite, phenyl • 4,4′-isopropylidene diphenol / pentaerythritol diphosphite, tris [ 4,4′-isopropylidenebis (2-t-butylphenol)] phosphite, phenyl diisodecyl phosphite, di (nonylphenyl) pentaerythritol diphosphite, tris (1,3-desteraroyloxyisopropyl) phosphite, 4,4'-isopropylidenebis (2- -Butylphenol) di (nonylphenyl) phosphite, 9,10-di-hydro-9-oxa-9-oxa-10-phosphaphenanthrene-10-oxide, 4,4'-butylidene-bis (3 -Methyl-6-t-butylphenyl-di-tridecyl phosphite) and the like.

As the bis (dialkylphenyl) pentaerythritol diphosphite ester, a spiro type represented by the following general formula (IX) or a cage type represented by the following general formula (X) may be used. Usually, such a phosphite ester is used as a mixture of isomers for production reasons.

[0047]

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Here, R ¹¹ , R ¹² and R ¹³ are preferably a hydrogen atom or an alkyl group having 1 to 9 carbon atoms, particularly a tert-butyl group among branched alkyl groups. Is most preferably at positions 2, 4, and 6. Preferred phosphite esters are bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite, bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite. ,
Further, it is a phosphite having a structure in which a carbon atom and a phosphorus atom are directly bonded, for example, a compound such as tetrakis (2,4-di-t-butylphenyl) -4,4′-biphenylenediphosphonite. In the present invention, as the antioxidant, the phenolic antioxidant may be used alone, or two or more may be used in combination,
One type of phosphorus-based antioxidant may be used, or two or more types may be used in combination. However, it is advantageous to use one or more phenolic antioxidants and one or more phosphorus-based antioxidants in combination.

The amount of the antioxidant to be added is not particularly limited, but is appropriately selected according to various situations. Usually, the phenol-based antioxidant and the phosphorus-based antioxidant are added to the propylene-ethylene block copolymer. The total amount with the antioxidant is 1500 ppm by weight or more. If this amount is 150
If the amount is less than 0 ppm by weight, when used for blow molding, the recyclability of the resin composition is reduced, and the productivity may be reduced. If the amount is too large, the molded product may be colored or bleed may occur. Therefore, the preferable addition amount of this antioxidant is 2,000 to
6000 ppm by weight, especially 2500 to 45 ppm.
A range of 00 ppm by weight is preferred. The phenolic antioxidant is usually 500 ppm by weight or more, preferably 1000 to 5000 ppm by weight, more preferably 150 ppm by weight, based on the propylene-ethylene block copolymer.
It is preferably added in an amount of 0 to 3000 ppm by weight. On the other hand, as a phosphorus-based antioxidant, it is usually 500 ppm by weight or more, preferably 1000 to 5000 ppm by weight, more preferably 1500 to 3000 ppm by weight. Further, the mixing ratio of the phenolic antioxidant and the phosphorus antioxidant is preferably 1: 5 to 5: 1, more preferably 1: 3 to 3: 1, and particularly preferably 1: 5 by weight ratio. 2
２2: 1. If the mixing ratio of the phenolic antioxidant and the phosphorus-based antioxidant is outside the above range, when used for blow molding, the recyclability of the resin composition may decrease.

In the present invention, an antioxidant other than the phenolic antioxidant and the phosphorus antioxidant may be used in combination. In this case, the amount of the total antioxidant added is usually 1600 ppm by weight or more, preferably 2100 ppm by weight, based on the propylene-ethylene block copolymer.
-10000 weight ppm, more preferably 2600-4
It is better to select within the range of 500 ppm by weight. Also in this case, it is advantageous that the mixing ratio of the phenolic antioxidant and the phosphorus antioxidant is in the above range. Here, as the antioxidant other than the phenolic antioxidant and the phosphorus-based antioxidant, a thioether-based antioxidant can be preferably exemplified. As the thioether-based antioxidant, conventionally known ones, for example, dilauryl-,
Dialkylthiodipropionates such as dimyristyl- and distearyl- and polyhydric alcohols of alkylthiopropionic acids such as butyl-, octyl-, lauryl- and stearyl- (eg glycerin, trimethylolethane, trimethylolpropane, pentaerythritol,
Esters of trishydroxyethyl isocyanurate (eg, pentaerythritol tetralauryl thiopropionate). More specifically, dilauryl thiodipropionate, dimyristyl thiodipropionate, distearyl thiodipropionate, lauryl stearyl thiodipropionate, distearyl thiodibutyrate and the like can be mentioned. One of these thioether-based antioxidants may be used, or two or more of them may be used in combination.

The nucleating agent used as an essential component in the resin composition of the present invention is a substance having a nucleating effect on the propylene-ethylene block copolymer. It is not particularly limited as long as it induces crystal nuclei promptly and reduces the degree of supercooling required for crystallization to start without reducing physical properties, and is not particularly limited, and is conventionally used as a nucleating agent for conventional polypropylene resins. Any one of those described above can be appropriately selected and used. Examples of such nucleating agents include high melting point polymers, organic carboxylic acids or metal salts thereof, organic phosphoric acid compounds or metal salts thereof, dibenzylidene sorbitols, partial metal salts of rosin acid, inorganic fine particles, imides, amides Quinacridones, quinones, and mixtures thereof. Among them, high melting point polymers, metal salts of organic carboxylic acids, inorganic fine particles, metal salts of organic phosphates and dibenzylidene sorbitols are preferred.

Examples of the high melting point polymer include polyolefins such as polyethylene and polypropylene, polyvinylcycloalkanes such as polyvinylcyclohexane and polyvinylcyclopentane, poly3-methylpentene-1, poly3-methylbutene-1, and polyalkenylsilane. No. As organic carboxylic acid metal salts,
Examples include aluminum benzoate, pt-butyl aluminum benzoate, sodium adipate, sodium thiophenecarboxylate, sodium pyrrolecarboxylate and the like. Examples of inorganic fine particles include talc,
Clay, mica, asbestos, glass flake, glass beads, calcium silicate, montmorillonite, bentonite, graphite, aluminum powder, alumina,
Silica, diatomaceous earth, titanium oxide, magnesium oxide, pumice powder, pumice balloon, aluminum hydroxide, magnesium hydroxide, basic magnesium carbonate, dolomite, calcium sulfate, potassium titanate, barium sulfate, calcium sulfite, molybdenum sulfide, etc. No. Examples of the metal organic phosphate include compounds represented by the general formula (XI)

[0053]

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(Wherein R ¹⁴ represents an oxygen atom, a sulfur atom or a hydrocarbon group having 1 to 10 carbon atoms, R ¹⁵ and R ¹⁶ each represent a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, ¹⁵
And R ^16, which may be the same as or different from each other, also R ¹⁵ together may form a R ¹⁶ s or R ¹⁵ and R ¹⁶ are bonded to each other ring structure, M is one to three A valent metal atom, n represents an integer of 1 to 3; ) Or the general formula (XII)

[0055]

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(Wherein, R ¹⁷ is a hydrogen atom or a group having 1 to 1 carbon atoms)
0 is a hydrocarbon group, M is a monovalent to trivalent metal atom, and n is 1 to 3
Indicates an integer. )). Examples of the compound represented by the general formula (XI) include:
Sodium-2,2'-methylene-bis (4,6-di-
t-butylphenyl) phosphate, sodium-2,
2'-ethylidene-bis (4,6-di-t-butylphenyl) phosphate, lithium-2,2'-methylene-
Bis- (4,6-di-t-butylphenyl) phosphate, lithium-2,2'-ethylidene-bis (4,6-
Di-tert-butylphenyl) phosphate, sodium-
2,2′-ethylidene-bis (4-isopropyl-6-
t-butylphenyl) phosphate, lithium-2,
2'-methylene-bis (4-methyl-6-t-butylphenyl) phosphate, lithium-2,2'-methylene-bis (4-ethyl-6-t-butylphenyl) phosphate, calcium-bis [2, 2'-thiobis (4-
Methyl-6-t-butylphenyl) phosphate], calcium-bis [2,2′-thiobis (4-ethyl-6
-T-butylphenyl) phosphate], calcium-
Bis [2,2′-thiobis- (4,6-di-t-butylphenyl) phosphate], magnesium-bis [2
2'-thiobis (4,6-di-t-butylphenyl) phosphate], magnesium-bis [2,2'-thiobis- (4-t-octylphenyl) phosphate], sodium-2,2'-butylidene- Screw (4,6-di-
Methylphenyl) phosphate, sodium-2,2 '
Butylidene-bis (4,6-di-t-butylphenyl)
Phosphate, sodium-2,2'-t-octylmethylene-bis (4,6-di-methylphenyl) phosphate, sodium-2,2'-t-octylmethylene-
Bis (4,6-di-t-butylphenyl) phosphate, calcium-bis- (2,2′-methylene-bis (4,6-di-t-butylphenyl) phosphate),
Magnesium-bis [2,2′-methylene-bis (4
6-di-t-butylphenyl) phosphate], barium-bis [2,2′-methylene-bis (4,6-di-t
-Butylphenyl) phosphate], sodium-2,
2'-methylene-bis (4-methyl-6-t-butylphenyl) phosphate, sodium-2,2'-methylene-bis (4-ethyl-6-t-butylphenyl) phosphate, sodium (4,4 ' -Dimethyl-5,6 '
-Di-t-butyl-2,2'-biphenyl) phosphate, calcium-bis [(4,4'-dimethyl-6,6
6'-di-t-butyl-2,2'-biphenyl) phosphate], sodium-2,2'-ethylidene-bis (4-n-butyl-6-t-butylphenyl) phosphate, sodium-2,2 '-Methylene-bis (4,6
-Di-methylphenyl) phosphate, sodium-
2,2'-methylene-bis (4,6-di-ethylphenyl) phosphate, potassium-2,2'-ethylidene-
Bis (4,6-di-t-butylphenyl) phosphate, calcium-bis [2,2′-ethylidene-bis (4,6-di-t-butylphenyl) phosphate],
Magnesium-bis [2,2'-ethylidene-bis (4,6-di-t-butylphenyl) phosphate],
Barium-bis [2,2'-ethylidene-bis (4,6
-Di-t-butylphenyl) phosphate], aluminum-tris [2,2′-methylene-bis (4,6-di-t-butylfell) phosphate] and aluminum-tris [2,2′-ethylidene-bis ( 4,6-di-t-butylphenyl) phosphate]. Among them, sodium-2,2'-methylene-bis (4,6-di-t-butylphenyl) phosphate is particularly preferred.

On the other hand, examples of the compound represented by the general formula (XII) include sodium-bis (4-t-butylphenyl) phosphate, sodium-bis (4-methylphenyl) phosphate, and sodium-bis (4 -Ethylphenyl) phosphate, sodium-bis (4-isopropylphenyl) phosphate, sodium-bis (4-t-octylphenyl) phosphate, potassium-bis (4-t-butylphenyl) phosphate, calcium-bis (4-t -Butylphenyl) phosphate, magnesium-bis (4-t-butylphenyl) phosphate, lithium-bis (4-t-butylphenyl) phosphate, aluminum-bis (4-t-butylphenyl) phosphate and the like. Among these, sodium-bis (4-t-butylphenyl) phosphate is particularly preferred. Next, as dibenzylidene sorbitols, for example, those represented by the general formula (XIII)

[0058]

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(Wherein, R ¹⁸ represents a hydrogen atom, a halogen atom, or an alkyl group or an alkoxyl group having 1 to 10 carbon atoms). Examples of the compound represented by the general formula (XIII) include 1,3,2,4-dibenzylidene sorbitol,
1,3-benzylidene-2,4-p-methylbenzylidene sorbitol, 1,3-benzylidene-2,4-p-
Ethylbenzylidene sorbitol, 1,3-p-methylbenzylidene-2,4-benzylidene sorbitol,
1,3-p-ethylbenzylidene-2,4-benzylidene sorbitol, 1,3-p-methylbenzylidene-
2,4-p-ethylbenzylidene sorbitol, 1,3
-P-ethylbenzylidene-2,4-p-methylbenzylidene sorbitol, 1,3,2,4-di (p-methylbenzylidene) sorbitol, 1,3,2,4-di (p
-Ethylbenzylidene) sorbitol, 1,3,2,4
-Di (pn-propylbenzylidene) sorbitol,
1,3,2,4-di (p-isopropylbenzylidene)
Sorbitol, 1,3,2,4-di (pn-butylbenzylidene) sorbitol, 1,3,2,4-di (p-
(s-butylbenzylidene) sorbitol, 1,3,2
4-di (pt-butylbenzylidene) sorbitol,
1,3,2,4-di (2,4-dimethylbenzylidene)
Sorbitol, 1,3,2,4-di (p-methoxybenzylidene) sorbitol, 1,3,2,4-di (p-ethoxybenzylidene) sorbitol, 1,3-benzylidene-2,4-p-chlorobenzylidene Sorbitol,
1,3-p-chlorobenzylidene-2,4-benzylidene sorbitol, 1,3-p-chlorobenzylidene-
2,4-p-methylbenzylidene sorbitol, 1,3
-P-chlorobenzylidene-2,4-p-ethylbenzylidenesorbitol, 1,3-p-methylbenzylidene-2,4-p-chlorobenzylidenesorbitol, 1,
3-p-ethylbenzylidene-2,4-p-chlorobenzylidene sorbitol and 1,3,2,4-di (p-chlorobenzylidene) sorbitol. Among these, in particular, 1,3,2,4-dibenzylidene sorbitol, 1,3,2,4-di (p-methylbenzylidene) sorbitol, 1,3,2,4-di (p-ethylbenzylidene) Sorbitol, 1,3-p-chlorobenzylidene-2,4-p-methylbenzylidene sorbitol, 1,3,2,4-di (p-chlorobenzylidene) sorbitol are preferred.

In the present invention, one of these nucleating agents may be used alone, or two or more of them may be used in combination.
The amount of the nucleating agent is usually 0.001 to 1 based on 100 parts by weight of the propylene-ethylene block copolymer.
0 parts by weight, preferably 0.01 to 5 parts by weight, more preferably 0.1 to 3 parts by weight. The resin composition of the present invention may contain, if desired, various other components other than an antioxidant and a nucleating agent, such as a heat stabilizer, a weather stabilizer, an antistatic agent, a chlorine scavenger, a slip agent, a flame retardant, Colorants, soft elastomers, modified polyolefins, inorganic or organic fillers, etc. can be included. The method for preparing the resin composition of the present invention is not particularly limited, and a conventionally known method can be used. Specifically, a propylene-ethylene block copolymer, an antioxidant, a nucleating agent, and various optional components used as needed are mixed, and mixed with a tumbler blender, a Henschel mixer, and the like. It can be prepared by melt-kneading and granulating using an extruder or by melt-kneading and granulating with a kneader, Banbury mixer or the like.

The resin composition thus obtained has good drawdown resistance, is lightweight, and has excellent balance between rigidity and impact resistance, and excellent balance between heat resistance and impact resistance. In particular, large blow-molded parts exceeding 5 kg in weight can be obtained with good moldability. The blow molded article of the present invention is
The resin composition can be produced by blow molding with a conventionally known blow molding apparatus. Also, conventionally known molding conditions can be adopted. For example, in the case of extrusion blow molding, the resin temperature 25
At a temperature of 0 ° C. or lower, preferably 180 to 230 ° C., more preferably 205 to 225 ° C., the resin composition is extruded from a die in a molten state as a tubular barison, and then a mold having a shape to be applied After holding the above barison therein, air is blown into the mold and the mold is attached to obtain a hollow molded product. The stretching ratio is preferably about 1 to 5 times in the transverse direction.

At this time, if the blow molding is performed at a resin temperature exceeding 250 ° C., the drawdown becomes severe, and there is a possibility that molding failure may occur. Further, if the blow molding is performed at a resin temperature of less than 180 ° C., the discharge amount becomes insufficient, which causes a decrease in productivity. The blow-molded article of the present invention thus obtained is excellent in dimensional stability and heat resistance, has a high level of balance between rigidity and impact resistance, and is particularly excellent in low-temperature barrier properties. Therefore, it can be used for bumpers such as automobile bumpers and bumper beams, trunk boards, seat backs, instrument panels, spoilers, etc., and is particularly suitably used for large automobile parts such as bumpers.

[0063]

Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. In addition, various properties of the propylene-ethylene block copolymer obtained in each example were measured according to the method described in the specification text, and the physical properties of the molded article were as follows:
It was measured according to the following method. (1) Flexural modulus The flexural modulus at 23 ° C. of an injection-molded product is measured according to JIS K7203. (2) Tensile modulus and elongation at break In accordance with JIS K7113, the flexural modulus and elongation at break of an injection molded product at 23 ° C. are measured. Although other resin properties need to be considered, samples exhibiting greater elongation at break are considered to have greater impact energy absorption. (3) Impact resistance (Izod impact strength) According to JIS K7110, -30 ° C of the injection molded product
The Izod impact strength with a notch is measured. (4) Low Temperature Barrier Tes
t) Federal Motor Vehicle Safe
ty Standards; abbreviation FMVSS) A barrier test is performed in accordance with PART 581. That is, a bumper beam is attached to a truck weighing 1500 kg, and the bumper beam collides with a barrier (wall) at a speed of 8 km / hour to measure the amount of deformation and the presence or absence of breakage. The collision is performed at a temperature of -30 ° C and in the center of the bumper beam. (5) Drawdown resistance Required parison length / parison heavy [Pamper beam: 1
400 mm × 100 mm × 100 mm / 10 kg] was injected from the accumulator, and the change in parison length up to 5 seconds until the mold was closed was evaluated. When the parison length of the completion of injection 5 seconds after the L, and the parison length at the completion of injection was L _0, drawdown resistance excellent as L / L ₀ is small, is particularly suitable for molding large material. The molding conditions are the same as in Examples 6, 7 and Comparative Example 7. (6) Heat resistance (HDT) The heat resistance of the injection molded article was measured in accordance with JIS K7207 (B method).

Preparation Example 1 Preparation of Catalyst A (1) Preparation of Solid Catalyst Component 160 g of diethoxymagnesium was placed in a three-necked flask equipped with a stirrer having an inner volume of 5 liter and replaced with nitrogen, and further dehydrated n-heptane 600 Milliliter was added. The mixture was heated to 40 ° C., 24 ml of silicon tetrachloride was added, the mixture was stirred for 20 minutes, and 25 ml of dibutyl phthalate was added. The temperature of the solution was raised to 80 ° C., and 770 ml of titanium tetrachloride was subsequently added dropwise using a dropping funnel. Thereafter, the stirring was stopped to settle the solid, the supernatant was extracted, and the solid was washed seven times using 110 ° C. dehydrated n-decane. Furthermore, after adding 1220 ml of titanium tetrachloride, making the internal temperature 110 ° C., and bringing into contact for 2 hours,
Washing is performed 6 times using dehydrated n-decane at 110 ° C.,
A solid catalyst component was obtained.

(2) Preliminary polymerization 48 g of the solid catalyst component obtained in the above (1) was put into a three-necked flask equipped with a stirrer having an inner volume of 1 liter and purged with nitrogen, and 400 ml of dehydrated n-heptane was added. Was. Heat to 40 ° C and triethyl aluminum
After adding 2.0 ml and 2.8 ml of 1,1-dimethoxy-2.6-dimethyl-1-silacyclohexane, propylene gas was allowed to flow at normal pressure and reacted for 2 hours. Thereafter, the solid component was sufficiently washed with dehydrated n-heptane to prepare Catalyst A.

Preparation Example 2 Preparation of Catalyst B (1) Preparation of Solid Catalyst Component 160 g of diethoxymagnesium was charged into a 5-liter three-necked flask equipped with a stirrer and purged with nitrogen. Milliliter was added. The mixture was heated to 40 ° C., added with 24 ml of silicon tetrachloride, stirred for 20 minutes, and added with 16 ml of dibutyl phthalate. The temperature of the solution was raised to 80 ° C., and 770 ml of titanium tetrachloride was added dropwise using a dropping funnel. Then, the solution was contacted at 125 ° C. for 2 hours.
Thereafter, the stirring was stopped to allow the solid to settle, and the supernatant was extracted. Add 100 ml of dehydrated n-decane,
After the temperature was raised to 135 ° C. with stirring and maintained for 1 minute, the stirring was stopped to solidify the solid, and the supernatant was taken out. After repeating this washing operation seven times, 1220 ml of titanium tetrachloride was added, the internal temperature was set to 135 ° C., and
Contact for an hour. Thereafter, washing with 135 ° C. dehydrated n-decane was repeated six times to obtain a solid catalyst catalyst component. (2) Preliminary polymerization Preparation Example 1 (2) using the solid catalyst component obtained in (1) above.
By performing the same operation as described above, Catalyst B was prepared.

Preparation Example 3 Preparation of Catalyst C (1) Preparation of Solid Catalyst Component 160 g of diethoxymagnesium was charged into a three-necked flask equipped with a stirrer having an internal volume of 5 liter and replaced with nitrogen, and further dehydrated n-heptane 600 Milliliter was added. The mixture was heated to 40 ° C., 24 ml of silicon tetrachloride was added, the mixture was stirred for 20 minutes, and 23 ml of diethyl phthalate was added. The temperature of the solution was raised to 80 ° C., and 770 ml of titanium tetrachloride was subsequently added dropwise using a dropping funnel. Thereafter, the stirring was stopped to allow the solid to settle, the supernatant was extracted, and the solid was washed seven times with 90 ° C. dehydrated n-heptane. Furthermore, after adding 1220 ml of titanium tetrachloride, making the internal temperature 110 ° C., and bringing into contact for 2 hours,
Washing is performed 6 times with dehydrated n-heptane at 90 ° C.,
A solid catalyst component was obtained. (2) Preliminary polymerization 48 g of the solid catalyst component obtained in the above (1) was placed in a 1-liter three-necked flask equipped with a stirrer and purged with nitrogen, and then 400 ml of dehydrated n-heptane was added. Then, at 10 ° C., 2.7 ml of triethylaluminum and 2.0 ml of cyclohexylmethyldimethoxysilane were added, and propylene gas was passed therethrough at normal pressure to react for 2 hours. Thereafter, the solid component was sufficiently washed with dehydrated n-heptane to prepare a contact C.

Example 1 In a stainless steel autoclave having an internal volume of 10 liter and equipped with a stirrer, 6 liter of n-heptane, 10 mmol of triethylaluminum, 2.5 mmol of dicyclopentyldimethoxysilane and 0.05 mmol of the catalyst A obtained in Preparation Example 1 ( (As Ti). Then, the liquidus temperature is raised to 80
C., hydrogen was supplied to the pressure indicated in the propylene polymerization part production conditions in Table 1, and stirring was continued for 120 minutes while continuously supplying propylene gas to the autoclave so that the reaction pressure became 0.8 MPa. Then, propylene was polymerized. Thereafter, unreacted propylene is removed and the temperature is reduced to 5
While maintaining the temperature at 7 ° C., hydrogen was supplied up to the pressure indicated in the propylene-ethylene copolymer production conditions in Table 1, and a mixed gas of propylene and ethylene in the mixing ratio shown in Table 1 was reacted at a reaction pressure of The propylene and ethylene were continuously supplied so as to be 0.6 MPa, and copolymerization of propylene and ethylene was performed for 20 minutes.

After depressurization, the solvent in the slurry was removed by an evaporator to obtain a propylene-ethylene block copolymer. Table 2 shows the structural analysis results of the obtained propylene-ethylene block copolymer. Further, 500 ppm by weight of "calcium stearate G" (manufactured by NOF Corporation: calcium stearate) as a neutralizing agent and "P-EPQ" as an antioxidant were added to the obtained propylene-ethylene block copolymer. Asahi Denka Kogyo KK: Tetrakis (2,4-di-tert-butylphenyl) -4,
4′-biphenylenediphosphonite] at 1000 ppm by weight, and “Irganox 1010” (manufactured by Ciba Specialty Chemicals: tetrakis [methylene-3-
(3,5-di-tert-butyl-4-hydroxyphenyl) propionate] methane) at 2000 weight pp
m, 1000 ppm by weight of "Irgafos 168" (manufactured by Ciba Specialty Chemicals: Tris (2,6-di-tert-butylphenyl) phosphite), and "Adecastab NA11" as a nucleating agent [Asahi Denka Kogyo Co., Ltd.]
2,000 ppm by weight of methylene bis (2,4-di-t-butylphenol) acid phosphate], mixed well, and melt-kneaded and granulated with a twin-screw kneading extruder to obtain a pellet-shaped resin composition. Prepared.
The pellets were injection molded to produce respective test pieces, and the physical properties were measured. The results are shown in Table 3.

Example 2 The procedure of Example 1 was repeated, except that the polymerization conditions at each stage were changed as shown in Table 1. The results are shown in Tables 2 and 3. Example 3 Example 3 was carried out in the same manner as in Example 1, except that the polymerization of propylene was carried out in two stages under the conditions shown in Table 1. The results are shown in Tables 2 and 3. Example 4 Example 4 was carried out in the same manner as in Example 1 except that the catalyst B obtained in Preparation Example 2 was used instead of the catalyst A.
The results are shown in Tables 2 and 3. Example 5 Example 5 was carried out in the same manner as in Example 1, except that Catalyst B was used instead of Catalyst A, and the polymerization conditions were changed as shown in Table 1. The results are shown in Tables 2 and 3.

Comparative Examples 1 to 4 The same procedures as in Example 1 were carried out except that the polymerization conditions at each stage were changed as shown in Table 1. The results are shown in Tables 2 and 3. Comparative Example 5 In Example 1, the catalyst C obtained in Preparation Example 3 was used in place of the catalyst A, and cyclohexylmethyldimethoxysilane was used instead of dicyclopentyldimethoxysilane, and the polymerization conditions were changed as shown in Table 1. Except having performed, it carried out similarly to Example 1. The results are shown in Tables 2 and 3.

Comparative Example 6 In a stainless steel autoclave having an internal volume of 10 liters and equipped with a stirrer, 4 liters of n-heptane, 5.7 mmol of diethylaluminum chloride, 0.79 g of titanium trichloride (manufactured by Marubeni Solvay) and 0.7% of ε-caprolactone were added. 2 ml was charged. Then, the liquidus temperature is maintained at 60 ° C.
Hydrogen was supplied up to the pressure indicated in the propylene polymerization section production conditions (first stage) in Table 1, and propylene gas was continuously supplied to the autoclave so that the reaction pressure became 0.9 MPa, followed by stirring for 90 minutes. Then, the first-stage polymerization was performed. Thereafter, unreacted propylene was removed, and the temperature was reduced to 60 ° C.
While maintaining the pressure, hydrogen was supplied up to the pressure indicated in the propylene polymerization part production conditions (second stage) in Table 1, and propylene gas was continuously supplied so that the reaction pressure became 0.7 MPa. The second stage polymerization was carried out for 40 minutes. Further, while maintaining the temperature at 57 ° C., hydrogen was supplied to the pressure indicated in the propylene-ethylene copolymer production conditions in Table 1;
A mixed gas of propylene and ethylene having a mixing ratio shown in Table 1 was continuously supplied so that the reaction pressure became 0.5 MPa, and the third-stage polymerization was performed for 30 minutes. After depressurizing,
After adding n-butanol to the polymerization product and stirring at 65 ° C. for 1 hour to decompose the catalyst, a propylene-ethylene block copolymer was obtained through the steps of separation, drying and washing. Table 2 shows the structural analysis results of the obtained propylene-ethylene block copolymer. Furthermore, a pellet-shaped resin composition was prepared in the same manner as in Example 1, and physical properties were measured. The results are shown in Table 3.

[0073]

[Table 1]

[0074]

[Table 2]

[0075]

[Table 3]

[0076]

[Table 4]

Examples 6 and 7 and Comparative Example 7 The scale was increased according to the conditions of Examples 1, 3 and Comparative Example 6 to produce a propylene-ethylene block copolymer. A pellet-shaped resin composition was prepared in the same manner as in Example 1 using each propylene-ethylene block copolymer. Next, the bumper beam for automobile (140
(0 × 100 × 100 mm, product weight 6 kg) was blow molded. The low-temperature barrier properties of this automotive bumper beam were evaluated. The results are shown in Table 4. (Molding conditions) Molding machine: 90 mmφ Screw: 90 mmφ Die: 100 mmφ Accumulator: 15 liters Mold clamping pressure: 60 t Screw rotation speed: 40 rpm Motor load: 115 A In the following, No. 1 is the hopper side. Cylinder No. 1: 230 ° C. Cylinder No. 2: 210 ° C. Cylinder No. 3: 190 ° C. Cylinder No. 4: 190 ° C. Crosshead No. 1: 190 ° C. Crosshead No. 2: 190 ° C. Crosshead No. 3: 190 ° C. Die No. 1: 190 ° C. Die No. 2: 190 ° C Cooling time: 200 sec Mold temperature: 40 ° C Resin temperature: 225 ° C

[0078]

[Table 5]

[0079]

The propylene-ethylene block copolymer of the present invention has good heat resistance and good drawdown resistance, and also has an improved balance between rigidity and impact resistance, especially improved rigidity and low temperature barrier properties. As a result, it is possible to provide a blow molded article suitably used for large automobile parts such as bumpers with high productivity.

[Brief description of the drawings]

FIG. 1 is a flowchart showing one example of a method for producing a propylene-ethylene block copolymer of the present invention.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) C08K 5/00 C08K 5/00 C08L 53/00 C08L 53/00 // B29K 23:00 B29K 23:00 B29L 31:30 B29L 31:30

Claims (7)

[Claims] 1. A temperature of 230 ° C. and a load of 2.16 kgf (21.
2N) Melt flow rate (MFR) measured under conditions
(A) 85 to 97% by weight of an insoluble component with respect to xylene at 25 ° C, and (B) 25 ° C at 25 ° C.
15 to 3% by weight of a soluble component with respect to xylene,
And the component (A) is (a-1) a stereoregularity index [m obtained by isotope carbon nuclear magnetic resonance spectroscopy ( ¹³ C-NMR) method;
[mmm] fraction is 98.0% or more, (a-2) 1
The intrinsic viscosity [η] measured in tetralin at 35 ° C is 2.5 to
Be 5.5 dl / g, and (a-3) Gel permeation chromatography (GPC) in terms of weight-average molecular weight Mw and the molecular weight ^104.5 ingredient content of less obtained [S (wt%)] has the formula (I) S ≦ −5.3 × 10 ⁻⁶ Mw + 7.58 (I) (where Mw is a weight average molecular weight) and the component (B) is (b) -1) ¹³ C-
The ethylene unit content determined by NMR is 30 to 70% by weight, and (b-2) the intrinsic viscosity [η] measured in tetralin at 135 ° C. is 2.5 to 9.0 deciliter / g.
A propylene-ethylene block copolymer, characterized in that: (C) (c-1) a magnesium compound,
(C-2) a solid catalyst component formed from a titanium compound, (c-3) an electron donor and optionally used (c-4) a silicon compound, (D) an organoaluminum compound, and (E) an electron donor. 2. The method for producing a propylene-ethylene block copolymer according to claim 1, wherein propylene and ethylene are polymerized in a multistage manner in the presence of a highly stereoregular catalyst system comprising a hydrophilic compound. 3. A resin composition comprising the propylene-ethylene block copolymer according to claim 1, an antioxidant, and a nucleating agent. 4. A blow molded article obtained by molding the propylene-ethylene block copolymer according to claim 1. 5. A blow molded article obtained by molding the resin composition according to claim 3. 6. The blow molded article according to claim 4, which is used for automobile bumpers. 7. The blow molded article according to claim 5, which is used for bumpers for automobiles.