JPH11349746A - Resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a polypropylene-based resin composition having excellent rigidity and impact strength at low temperatures. SOLUTION: This is a polypropylene resin(PP)/ethylene-propylene copolymer rubber(EPR) composition having the following properties: (1) weight-average molecular weight of PP is 10,000-1,000,000; (2) mesopentad chain of PP is 95% or more; (3) weight-average molecular weight of EPR is 50,000-1,000,000; (4) propylene content of EPR is 20-80 mol.%; (5) molecular weight-dependency of EPR composition is within ±5% fluctuation; (6) interfacial thickness between PR component and EPR component is 20-1,000 nm; and (7) dispersion particle size of EPR is 0.2-10 μm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition containing a polypropylene resin (hereinafter, referred to as "PP resin") and an ethylene-propylene copolymer rubber (hereinafter, referred to as "EPR") as main components, and particularly to a rigid composition. And the above resin composition having excellent impact strength at low temperatures.

[0002]

2. Description of the Related Art Resin compositions (often called "polymer blends", "polymer alloys", etc.) obtained by melting and mixing two or more kinds of resins maintain the advantages of each component resin. In many cases, the disadvantages can be compensated for, and various studies have been made. Above all, in a resin composition obtained by blending EPR as a rubber component with PP resin as a crystalline resin, the properties change according to the type and characteristics of each component. It was necessary to study the proper formulation. In particular, when this is used for applications such as structural materials, impact resistance and rigidity at low temperatures are required, but a technique for balancing these at a high level has not yet been established.

[0003]

An object of the present invention is to provide a polypropylene resin composition which is excellent in rigidity and impact strength at low temperatures.

[0004]

Means for Solving the Problems The present inventors have solved the above problems by using a polypropylene resin (PP resin).
As a result of a detailed study of the crystal structure, dispersion state, and the like of a composition containing ethylene and propylene copolymer rubber (EPR) as a main component, by setting a specific characteristic value within a certain range, It has been found that the object of the present invention is achieved and the present invention has been completed. That is, the gist of the present invention is a resin composition containing, as a main component, a PP resin and 5 to 100 parts by weight of EPR per 100 parts by weight of the resin. (7) The resin composition having the characteristic value of (7). (1) Weight average molecular weight of PP resin (hereinafter referred to as “MW _{· PP} ”): 10,000 ≦ MW _{· PP} ≦ 1,000,000 (2) Ratio of mesopentad chain of PP resin: 95% or more ( 3) Weight average molecular weight of EPR (hereinafter referred to as “MW _{· R} ”): 50,000 ≦ MW _{· R} ≦ 1,000,000 (4) Propylene content in EPR: 20 mol% or more;
80 mol% or less (5) Composition variation due to EPR molecular weight: ± from average composition
Within 5% (6) PP resin component and E in dispersed structure of resin composition
Interface thickness with PR component: 20 nm or more and 1000 nm or less (7) Circular particle size equivalent to weight average area of dispersed phase of EPR in the resin composition: 0.2 μm or more and 10 μm or less Hereinafter, the present invention will be described in detail. .

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The resin composition of the present invention has characteristics not only in the PP resin and EPR constituting the resin composition, but also in the dispersed state of each component in the dispersed structure of the composition and the state of their interface. There are also features. Hereinafter, each characteristic value will be described. The weight average molecular weight (MW _{/ PP} ) of the polypropylene resin (PP resin) which is the main component of the composition of the present invention is 10,000 or more and 1,000,000 or less, preferably 50,000 or more, 800,000 or less, and more preferably 10,000,000 or less. 10,000 or more, 4
It is below 10,000.

[0006] If the weight average molecular weight is low, the mechanical strength decreases, while if it is too high, the melt viscosity increases during molding and processability deteriorates. The weight average molecular weight M _{W · PP} is measured as a molecular weight in terms of polypropylene by gel permeation chromatography (GPC). This M
_{W · PP} has the following relationship with the melt flow rate (hereinafter referred to as “MFR”) used as an index of the molecular weight and the intrinsic viscosity [η] in ortho-dichlorobenzene.

[0007]

[Η] = 3.91 × 10^-Four× M_{W / PP} ^-0.7  log (MFR) = 2.716-1.1 [η]

The ratio Q between the weight average molecular weight and the number average molecular weight, which is an index of the molecular weight distribution, is not particularly limited, but if Q exceeds 6, the characteristic dispersion form of the present invention may not be realized. More preferable value of Q is 1.5 to
5 The isotactic stereoregularity of the polypropylene resin used in the present invention is such that the proportion of mesopentad chains measured by NMR spectrum is 95% or more, preferably 97% or more. When the isotactic stereoregularity decreases, the crystallinity decreases, and the rigidity decreases.
Note that, depending on the production method, a small amount of an atactic polymer component may be present even if the ratio of the mesopentad chain, which is the average value, is a high value. The content of the atactic polymer component defined by the boiling heptane soluble component is 5% or less, preferably 3% or less, and more preferably 1% or less. The content of the 1,3-addition bond also measured by NMR spectrum is preferably 0.06 mol% or more and 3 mol% or less. More preferably, it is 0.2 mol% or more and 2.5 mol% or less. If this asymmetric bond exceeds 3 mol%, the melting point and crystallinity are greatly reduced. If it is less than 0.06 mol%, the improvement in rigidity corresponding to the density is small.

In the present invention, the melting point of the polypropylene resin is determined by using a differential scanning calorimeter (DSC) at a heating rate of 10
It refers to the melting peak temperature when measured at ° C./min.
The melting point of the polypropylene resin used in the present invention is 14
The temperature is preferably from 0 ° C. to 170 ° C. in the secondary processing step utilizing a melting process such as friction welding and secondary injection welding, in order to maintain the fusion strength by low melting point and low latent heat of crystallization. On the other hand, if the melting point is too low, the heat resistance, which is a characteristic characteristic of the polypropylene resin, is reduced, and the application is limited. on the other hand,
If the melting point is too high, it is difficult to melt at the time of processing, and processability deteriorates.

The long period L of the crystal structure referred to in the present invention is a crystal determined by small-angle X-ray scattering measurement based on a model structure in which the crystal structure of a polypropylene resin is a stack of plate (lamella) crystals. It is an amorphous repetition cycle. The detailed measurement method is described in the literature "Polymer Experiment 16
Polymer solid structure II "(published by Kyoritsu Shuppan, 1984), and the outline thereof is as follows. That is, assuming that the scattering angle in the X-ray scattering measurement is 2θ, the equation s = 2 sin θ / λ (λ
Is the scattering vector s given by (wavelength) and the value of s (smx which gives the maximum value of the curve obtained by plotting I (s) × s ² against s using the scattering intensity I (s) at that time.
). At this time, the long period L of the crystal structure is L =
It is given by 1 / smx. The measurement sample was melted at 260 ° C. for 10 minutes using a hot press molding machine, and then the thickness was 1 m.
It is good to use what was compression-molded to m and immediately cooled with water.

In the present invention, the long period L is 10n
It is preferably at least m and at most 15 nm. In the present invention, the weight average molecular weight (M) measured by gel permeation chromatography (GPC) of EPR is used.
_{W / R} ) is 50,000 or more and 1,000,000 or less. M _{W · R} is 1
000000 decreases the fluidity during hot forming and exceeding, while the appearance of the molded article is deteriorated, M _{W · R} is not sufficient impact resistance improving effect can be obtained is less than 50,000. More preferred M
_{W / R} is between 100,000 and 800,000. In the present invention, further, in the molecular weight distribution determined by GPC,
EPR having a ratio of components having a molecular weight of 10,000 or less, preferably 10% or less, more preferably 5% or less is suitable. When the low molecular weight component exceeds 10%, the elastic modulus of the PP resin is reduced, and the rigidity of the resin composition is reduced.
The propylene content in the EPR used in the resin composition of the present invention is not less than 20 mol% and not more than 80 mol%, preferably 3 mol%.
0 mol% or more and 75 mol% or less. If the propylene content is less than 20 mol%, the compatibility with the polypropylene will be reduced, the affinity of the interface between the PP resin and the EPR will be extremely reduced, and the mechanical properties will be reduced due to the interfacial separation. If the propylene content exceeds 80 mol%, the affinity for polypropylene increases, and the dispersion of the rubber becomes too fine, so that the stress concentration on the dispersed phase of EPR, which is the main mechanism of toughening, is effective. Also, the glass transition temperature of the ethylene-propylene copolymer increases, and the low-temperature impact strength tends to decrease and the embrittlement temperature tends to increase, which is also undesirable.

The propylene content in the EPR can be measured by a nuclear magnetic resonance spectrum ( ¹³ C-NMR). Further, the composition ratio of ethylene and propylene of the ethylene-propylene copolymer may change depending on the molecular weight. If the composition ratio has a distribution depending on the molecular weight, the interface thickness between the PP resin and the EPR, which is a feature of the present invention, may be reduced or the interface may not be formed at all. In the present invention, this EPR
Composition variation due to the molecular weight of the ethylene-propylene copolymer in the composition is within ± 5%, preferably ± 3%, of the average composition.
%. The fluctuation state of the composition due to the molecular weight can be determined by measuring the respective compositions of the polymer separated by the molecular weight by infrared absorption spectrum analysis, nuclear magnetic resonance spectrum analysis, or the like. Experimentally, it is convenient to connect an infrared detector to the flow cell of the GPC and measure the ratio of infrared characteristic absorption of ethylene units and propylene units.

The EPR used in the present invention is a mechanical loss angle tangent (tan δ) evaluated by the temperature dispersion of dynamic mechanical behavior.
However, it is preferable that an absorption maximum is exhibited at −65 ° C. or more and −30 ° C. or less, and the half width of the absorption curve is 20 ° or less. If the dispersion temperature is high, the effect of improving the impact strength at low temperatures, for example, -30 ° C, is small. On the other hand, in order to reduce the mechanical loss angle tangent to, for example, −70 ° C. or less, it is necessary to make the ethylene content 80% or more. And the effect of improving the impact resistance is reduced. The range of the transition temperature in dispersion varies depending on the intermolecular and intramolecular distribution of the copolymer composition. In the case of a material having a wide composition distribution such that the half-width of the transition temperature exceeds 20 ° C., the increase in the interface thickness in the dispersion state unique to the present invention is not observed, and the improvement in the low-temperature impact strength is small.

In a resin composition containing a PP resin and an EPR as main components, a PP resin component (PP
At the interface between the resin phase) and the EPR component (EPR phase)
An intrusion structure may be formed as if a lamellar needle-like crystal of polypropylene derived from the PP resin phase pierced the EPR phase. (Details regarding such a structure are described in “Polymer Alloy” p62, published by Kyoritsu Shuppan (1988).) In the present invention, the length of the needle-like intrusion structure is referred to as “interface thickness”. In other words, for the composition of the present invention, the thickness of the interface is 20 nm or more and 1000 nm or less.

The interface thickness is measured, for example, as follows. A section cut out from a molded article based on the composition was melted at 210 ° C. for 5 minutes using a differential scanning calorimeter (DSC7 manufactured by Perkin Elmer), and then cooled at 10 ° C./minute to prepare a sample. After staining with ruthenium, an observation image is obtained with a transmission electron microscope. The penetration length of the polypropylene lamella crystal penetrating from the interface that can be identified as a non-stained structure is measured over the entire periphery of the dispersion layer, and the average length is determined using 10% of the maximum length as the measurement lower limit, and this is defined as the interface thickness. . In the molded article, when a local change in the dispersion form such as the orientation of the strength of the dispersion in the vicinity of the surface occurs, it is better to evaluate the interface thickness at the most average portion in the center of the molded article. . In the present invention, the interface thickness is 20 nm or more and 1000 nm or less. If the interface thickness is less than 20 nm, the interface strength decreases and the low-temperature impact strength decreases. If it exceeds 1000 nm, the rigidity is greatly reduced.

In the composition of the present invention, the weight average area equivalent circular particle diameter, which is an index of the dispersion state of the EPR phase in the dispersion state of the composition, is 0.2 μm or more;
It is set to 10 μm or less. The weight average area equivalent circular particle diameter is determined by observation with a scanning electron microscope, a transmission electron microscope, an optical microscope, or the like. The area of the EPR particles in the observed image is obtained, and the diameter is converted to the diameter of a circle corresponding to the area to obtain the dispersed particle diameter. An observation visual field is determined so that 100 or more dispersions can be detected, and a circular particle diameter corresponding to the weight average area of the EPR is determined from the dispersion particle diameters of the 100 or more dispersions. A commercially available image analyzer can be used in the evaluation of the circle particle diameter corresponding to the weight average area.

The weight average area equivalent circular particle diameter is 0.2
If it is less than μm, the effect of improving the impact resistance is small, while
When it is larger than μm, poor appearance such as delamination tends to occur when the molded article is formed. A more preferable circle particle diameter equivalent to a weight average area is 0.5 μm or more and 3 μm or less. In the resin composition of the present invention, PP resin and EP
R is mixed with EPR per 100 parts by weight of PP resin.
5 to 100 parts by weight. The preferred amount of EPR is
It is 10 to 50 parts by weight, more preferably 10 to 30 parts by weight, based on 100 parts by weight of the PP resin.

When the amount of EPR exceeds 100 parts by weight, the improvement in impact resistance cannot be obtained in proportion to the increase in the amount, but the rigidity is greatly deteriorated. on the other hand,
If the amount is less than 5 parts by weight, the effect of improving the impact resistance at low temperatures cannot be obtained. The ethylene-propylene copolymer rubber used in the present invention is not limited to a substance having general rubber elasticity (Chemical Dictionary Tokyo Kagaku Dojin, 1994). A copolymer having an elastic modulus may be used. The preferred crystallinity of the EPR used is 15% or less, preferably 10% or less. The dynamic elastic modulus at 20 ° C. is preferably 10M.
It is Pa or less, more preferably 5 MPa or less. When the mechanical properties of the ethylene-propylene copolymer approach the polypropylene resin and become hard, the effect of reinforcing the impact strength is lost.

The composition of the present invention in which the polypropylene resin and the ethylene-propylene copolymer rubber are compounded may contain, if necessary, talc, calcium carbonate, titanium oxide, carbon black, mica, glass fiber and carbon fiber. , Metal fiber such as stainless steel, reinforcing material such as metal whisker, etc.
60 parts by weight can be blended. In addition, additives such as an antioxidant, a photodeterioration inhibitor, an antistatic agent, and a nucleating agent can be used.

[0020]

EXAMPLES Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited to the following examples unless it exceeds the gist. (1) Measurement method of characteristic value Preparation of measurement sample After weighing PP resin and EPR at a predetermined ratio, heat-resistant stabilizer was added to this, and Labo Plast Mill (manufactured by Toyo Seiki)
Was melt-mixed at 240 ° C. for 5 minutes to prepare a sample of the resin composition. The sample was melted at 260 ° C. for 10 minutes using a hot press molding machine (manufactured by Toyo Seiki), compression molded, and immediately cooled with water to prepare a measurement sample (test piece). Molecular weight average molecular weight (weight average molecular weight Mw and number average molecular weight M
n) is the viscosity equation of polypropylene from a molecular weight calibration curve using GPC (gel permeation chromatography, Waters GPC150C), eluent ortho-dichlorobenzene, temperature 140 ° C., and standard polystyrene.

[0021]

Η = 3.91 × 10 ^-4 · M ^-0.7

Calculated using In addition, the molecular weight distribution (Q
Value) is the ratio of Mw and Mn obtained here (Q = Mw / M
n). Content of mesopentad chain The content of the mesopentad chain [mmmm] and 1,3-addition bond of polypropylene was determined by dissolving the polymer in 2 ml of orthodichlorobenzene using a nuclear magnetic resonance spectrometer (JNM GSX270 manufactured by JEOL Ltd.). The measurement was performed by adding 0.5 ml of deuterated benzene as a locking solvent and measuring a nuclear magnetic resonance spectrum at a temperature of 130 ° C. 10 to improve S / N ratio
000 integration measurements were performed. The analysis is described in J.A. C. Rand
using the method proposed by All (Jun
al of Polymer Science 12,
703, (1974)), a mesopentad chain [mmm
m] was estimated. In addition, the quantification of the 1,3-addition bond
A. Macromolecules from Zambelli
21 (3), according to the method described in 617 (1988), belong peak, -CH ₂ -, - CH- in was performed by calculating the mol% from the sum of the carbon atoms.

Using a melting point differential scanning calorimeter (DSC7 manufactured by PerkinElmer),
The rate of temperature rise and fall from 20 to 200 ° C at a rate of 10 ° C / min.
It was obtained as the melting peak temperature at the time of the second temperature rise after performing this process. The long period L of the crystal structure was measured according to the method described in the text (“Embodiments of the Invention”). Rigidity (Olsen bending rigidity) It was measured according to JIS K-7106-82. Low temperature impact strength (Izod impact strength) Measured temperature -30 according to JIS K-7110-84
It was evaluated at ° C. Mechanical loss tangent (tan δ) The temperature dispersion of the mechanical loss tangent (tan δ) was measured at 2 ° C./min using a mechanical spectrometer manufactured by Rheometrics.
The distortion was measured at 1 radian at a frequency of 1 Hz. Composition of ethylene-propylene copolymer rubber (EPR) The propylene content of the ethylene-propylene copolymer is as follows:
Nuclear magnetic resonance spectrum (measurement: JNMGS × 27, manufactured by JEOL Ltd.)
0, o-dichlorobenzene / benzene-d6). N. Using the method proposed by Cheng et al. (Macromolecules 1984).
Year, Vol. 17, p1950).

Composition Variation Due to EPR Molecular Weight Composition variation due to the molecular weight of the ethylene-propylene copolymer was measured by using GPC manufactured by Waters, Shodex 806MS as a column, and Zero-Dead, vol. cl. And an IR made by Nicole Co. was used as a detector. 200 ml of EPR solution prepared to a concentration of 4 mg / ml using chloroform as a solvent
At room temperature at a flow rate of 1 ml for measurement. Resolution is 4
cm ⁻¹ . The analysis was performed using analysis software manufactured by Omrock Co., Ltd., and the intensity at 2950 cm ^{-1 and} the intensity at 2180 cm ^-1 were measured. The relationship between the molecular weight and the copolymer composition was evaluated based on the fact that the ratio of this intensity (I ₂₉₅₀ / I ₂₁₈₀ ) at each elution time was proportional to the ethylene fraction. When the intensity ratio at each molecular weight was within ± 5% of the average intensity ratio, the composition variation at this molecular weight was within ± 5% from the average composition.

(2) Examples and Comparative Examples Example 1 [PP resin] (sample a) (1) Preparation of catalyst component <Component (A) [dimethylsilylenebis {1,1 '-(2
Synthesis of -Methyl-4-phenyl-4-hydroazulenyl) {hafnium dichloride] The following reactions were all carried out under an inert gas atmosphere, and the reaction solvent used was previously dried.

(A) Synthesis of racemic-meso mixture 3.22 g of 2-methylazulene synthesized according to the method described in JP-A-62-207232 was dissolved in hexane 30
Then, 21 ml (1.0 equivalent) of a cyclohexane-diethyl ether solution of phenyllithium was added little by little at 0 ° C. After stirring this solution at room temperature for 1.5 hours, it was cooled to -78 ° C and 30 ml of tetrahydrofuran was added. 45 μmol of 1-methylimidazole was added to this solution.
And 1.37 ml of dimethyldichlorosilane were added, and the mixture was returned to room temperature and stirred for 1 hour. Thereafter, an aqueous solution of ammonium chloride was added thereto, and the mixture was separated. The organic phase was dried over magnesium sulfate, and the solvent was distilled off under reduced pressure to obtain bis {1,1 ′-(2
This gave 5.84 g of a crude product of -methyl-4-phenyl-1,4-dihydroazulenyl) {dimethylsilane.

The above-obtained crude product of bis {1,1 '-(2-methyl-4-phenyl-1,4-dihydroazulenyl)} dimethylsilane was dissolved in 30 ml of diethyl ether, and n was added at -78.degree. -Butyl lithium hexane solution 1
4.2 ml (1.6 mol / L) was added dropwise, and the mixture was gradually returned to room temperature and stirred for 12 hours. After evaporating the solvent under reduced pressure, toluene / diethyl ether (40: 1) 80 ml
, 3.3 g of hafnium tetrachloride is added at -60 ° C,
The mixture was gradually returned to room temperature and stirred for 4 hours. The obtained solution is concentrated under reduced pressure, and the obtained solid is washed with toluene, extracted with dichloromethane, and dimethylsilylenebis {1,1 ′
Racemic-meso mixture of-(2-methyl-4-phenyl-4-hydroazulenyl)} hafnium dichloride
74 g were obtained.

(B) Purification of the racemate The racemic-meso mixture obtained by the above reaction 1.74
g was dissolved in 30 ml of dichloromethane and introduced into a Pyrex glass container having a 100 W high-pressure mercury lamp. The solution was irradiated with light under normal pressure for 40 minutes while stirring to increase the ratio of the racemate, and then dichloromethane was distilled off under reduced pressure. 10 ml of toluene was added to the obtained yellow solid, and the mixture was stirred and filtered. The solids separated by filtration are treated with toluene 8
After washing with 4 ml of hexane and 4 ml of hexane, racemic 917 of dimethylsilylenebis {1,1 '-(2-methyl-4-phenyl-4-hydroazulenyl)} hafnium dichloride was obtained.
mg was obtained.

<Production of Component (C)> In a 500 ml round bottom flask, 135 ml of deionized water and 16 g of magnesium sulfate were collected and dissolved with stirring. To this solution was added 22.2 g of montmorillonite (Kunipia F, manufactured by Kunimine Industries), and the mixture was heated and treated at 80 ° C. for 1 hour. Then desalinated water 3
After adding 00 ml, the solid content was recovered. to this,
After adding 46 ml of demineralized water, 23.4 g of sulfuric acid and 29.2 g of magnesium sulfate, the mixture was heated and refluxed for 2 hours. After the treatment, 200 ml of demineralized water was added, followed by filtration. Further, 400 ml of demineralized water was added and the mixture was filtered, and this operation was repeated twice. Then, it was dried at 100 ° C. to obtain chemically treated montmorillonite. 1.05 g of the above chemically treated montmorillonite was collected in a 100 ml round bottom flask, and dried at 200 ° C. under reduced pressure for 2 hours. To this was added a toluene solution of triethylaluminum (0.5 mmol) under purified nitrogen.
1 / ml) and reacted at room temperature for 1 hour, and then washed twice with 30 ml of toluene to obtain a component (C) as a toluene slurry.

(2) Propylene Prepolymerization 0.6 ml of a toluene solution of triisobutylaluminum (0.5 mmol / ml) was added to the entire slurry and dimethylsilylenebis {1,1′-
19.1 ml of a toluene solution (1.5 μmol / ml) of (2-methyl-4-phenyl-4-hydroazulenyl) hafnium dichloridracemate was added, and contacted at room temperature for 10 minutes. Into a 2 L induction-stirring autoclave, 40 ml of toluene and the entire amount of the above contact substance were introduced under purified nitrogen. Propylene was introduced under stirring at a total polymerization pressure of 0.6 MPa at room temperature for 3 minutes.
Then, unreacted propylene was purged and the pressure was replaced with purified nitrogen, and then the prepolymerized catalyst was taken out. This contained 2.98 g of polymer per 1 g of component (C).

(3) Polymerization of Propylene 2 L having a built-in irrigated stirring blade replaced with purified nitrogen
Into an induction-stirring autoclave, a toluene solution of triisobutylaluminum (0.5 mmol / ml) was added in an amount of 0.6 mmol / ml.
After adding 1 ml of hydrogen gas and charging 12.9 KPa of hydrogen gas, 700 g of liquefied propylene was charged. Thereafter, the prepolymerized catalyst obtained in the above (2) was used as a solid catalyst component for 50.2 m
g, and after the temperature was raised, polymerization was carried out at 75 ° C. for 40 minutes. As a result, 471 g of a polypropylene resin was obtained. The properties of the obtained polypropylene resin are shown in Table 1.

[EPR] (Sample A) (4) Preparation of Catalyst Component <Component (A)> A racemic dimethylsilylenebis (2-methylbenzoindenyl) zirconium dichloride was used as a component (A) in a literature (Organometarlic).
s, 1994, 13, 964).

(5) Propylene Prepolymerization A glass reactor having an inner volume of 0.5 L and equipped with a stirrer was charged with W.
ITCO MAO (Methylaluminoxane) on S
2.4 g (20.7 mmol-Al) of iO ₂ were added,
50 ml of n-heptane were introduced. 20.0 ml of a toluene solution of racemic dimethylsilylenebis (2-methylbenzoindenyl) zirconium dichloride
(0.637 mmol), followed by a solution of triisobutylaluminum (TIBA) in n-heptane 4.14.
ml (3.03 mmol) was added. Thereafter, the reaction was carried out at room temperature for 2 hours, and propylene was circulated to carry out preliminary polymerization to obtain a solid catalyst component.

(6) Method for producing ethylene-propylene copolymer n-heptane 1.5 dehydrated and deoxygenated in an autoclave having a stirrer having an internal volume of 3 L and substituted with purified nitrogen.
L and then 100 m of triethylaluminum
g was added to bring the temperature to 65 ° C. Here, 150 mg of the prepolymerized catalyst obtained above was injected as a solid catalyst component, and a mixed gas of propylene / ethylene (ethylene concentration in the mixed gas = 30% by weight) mixed in another gas preparation tank was 5 kg /. Introduced to a pressure of cm ² · G,
The polymerization was carried out while maintaining the pressure and temperature for 3 hours. as a result,
163 g of an ethylene-propylene copolymer as shown in Table 1
I got

[Resin composition] PP obtained as described above
The resin and the EPR were weighed so as to have a predetermined composition (80/20 by weight in this example), and a resin composition was prepared according to the method described in the above (1) “Preparation of measurement sample”. , Was evaluated. Table 1 shows the results. The following examples,
Preparation and evaluation of the composition were performed in the same manner as in the comparative example.
(Evaluation results of the comparative examples are shown in Table 2.)

Example 2 [PP Resin] (Sample b) 2 L having a built-in irrigated stirring blade replaced with purified nitrogen
In a stirrer-type autoclave, a toluene solution of triisobutylaluminum (0.2 mmol / ml) was added for 1.5 times.
After adding 13.2 kPa of hydrogen gas, 700 g of liquefied propylene was charged. Thereafter, the prepolymerized catalyst obtained in Example 1 (2) was used as a solid catalyst component in 3 parts.
8.8 mg was injected, and after heating, polymerization was performed at 75 ° C. for 40 minutes. As a result, 214 g of a polypropylene resin was obtained. [EPR] (Sample b) Copolymerization of ethylene and propylene was carried out in the same manner as in Examples 1 (4) to (6) except that the ethylene concentration of the mixed gas was 60% by weight. As a result, an ethylene-propylene copolymer shown in Table 1 was obtained.

Example 3 [PP resin] (Sample c) (1) Preparation of catalyst component A solid catalyst component was obtained according to the method described in "Example 1, Component (A)" of JP-A-3-234707. Was.

(2) Polymerization of Propylene A liter of n-heptane, 25 L, purified after sufficiently replacing the stirred autoclave with an internal volume of 100 L with propylene,
Triethylaluminum n-heptane solution (0.1 m
ol / L) and 3.2 g of the solid catalyst component synthesized in the above (1) were introduced at a temperature of 65 ° C. Further, while maintaining the gas phase hydrogen concentration at 2.2% by volume, at a temperature of 75 ° C.,
213 propylene at a feed rate of 4.5 kg / hr.
After the feed, the polymerization was further continued for 40 minutes. Thereafter, the catalyst was decomposed using butanol, and the product was filtered and dried.
1 kg was obtained.

[EPR] (Sample A) As the EPR component of this example (Example 3), the EPR prepared in Example 1 (Sample A) was used. Table 1 shows the evaluation results.

Comparative Example 1 [PP Resin] (Sample c) The polypropylene (sample c) obtained in Example 3 was used as the PP resin. [EPR] (Sample C) 1.5 L of dehydrated and deoxygenated n-heptane was placed in an autoclave with a stirrer having an internal volume of 3 L, which was replaced with purified nitrogen.
And then diethylaluminum chloride 160
mg was added to bring the temperature to 65 ° C. Then, after injecting 40 mg of a titanium trichloride catalyst (O1 catalyst) manufactured by M & S Catalysts Co., and mixing in another gas regulating tank, a mixed gas of propylene / ethylene (ethylene concentration in the mixed gas: 25% by weight) ) Was introduced at a pressure of 5 kg / cm ² · G, and polymerization was carried out for 3 hours while maintaining the pressure and temperature. As a result, 181 g of an ethylene-propylene copolymer (EPR) as shown in Table 2 was obtained.

Comparative Example 2 [PP Resin] The polypropylene (sample a) described in Example 1 was used as the polypropylene resin. [EPR] The EPR (sample C) obtained in Comparative Example 1 was used as the ethylene-propylene copolymer.

(3) Evaluation of Results Examples 1 and 2 relating to a composition of a PP resin and an EPR having specific characteristic values of the present invention have a higher impact resistance than a comparative example which is out of the scope of the present invention. And good rigidity balance.

[0043]

[Table 1]

[0044]

[Table 2]

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Hiroyuki Nakano 1 Tohocho, Yokkaichi-shi, Mie Mitsubishi Chemical Corporation Yokkaichi Office (72) Inventor Toshihiko Sugano 1000 Kamoshida-cho, Aoba-ku, Yokohama-shi, Kanagawa-ken Mitsubishi Chemical Corporation (72) Inventor Tohru Suzuki 1000 Kamoshita-cho, Aoba-ku, Yokohama-shi, Kanagawa-ken Yokohama General Research Institute, Mitsubishi Chemical Corporation

Claims (3)

[Claims] 1. A polypropylene resin (hereinafter referred to as “PP resin”)
) And 5 to 100 parts by weight of ethylene-propylene copolymer rubber (hereinafter referred to as “EP
R ") as a main component, wherein the composition and each of the above components have the following characteristic values (1) to (7). (1) Weight average molecular weight of PP resin (hereinafter referred to as “MW _{· PP} ”): 10,000 ≦ MW _{· PP} ≦ 1,000,000 (2) Ratio of mesopentad chain of PP resin: 95% or more ( 3) Weight average molecular weight of EPR (hereinafter referred to as “MW _{· R} ”): 50,000 ≦ MW _{· R} ≦ 1,000,000 (4) Propylene content in EPR: 20 mol% or more;
80 mol% or less (5) Composition variation due to EPR molecular weight: ± from average composition
Within 5% (6) PP resin component and E in dispersed structure of resin composition
Interface thickness with PR component: 20 nm or more and 1000 nm or less (7) Circular particle diameter equivalent to weight average area of dispersed phase of EPR in the resin composition: 0.2 μm or more and 10 μm or less 2. The resin composition according to claim 1, wherein the PP resin has the following characteristic values (8) to (13). (8) Weight average molecular weight _{(M W · PP): 50,000} ≦ M W · PP ≦ 800,000 (9) the ratio of weight average molecular weight to number average molecular weight: 6 ratio of less (10) mesopentad chain: 97 (11) Ratio of 1,3-addition bond: 0.06 mol% to 3 mol% (12) Melting point (hereinafter referred to as “T _{m · PP} ”): 140 ° C. ≦ T _{m · PP} ≦ 170 ° C (13) Long period of crystal structure (hereinafter referred to as “L”): 10 nm ≦ L ≦ 15 nm 3. The resin composition according to claim 1, wherein the EPR has the following characteristic values (14) and (15). (14) Absorption maximum of mechanical loss angle tangent: −65 ° C. or more and −30 ° C. or less (15) Half width of absorption curve of mechanical loss angle tangent: 20 ° or less