JP2831576B2 - Propylene block copolymer, production method thereof and composition thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
The present invention relates to a propylene block copolymer excellent in rigidity, impact resistance, heat resistance and surface hardness, and a method for producing the same, which is suitably used in the field of electronic components, packaging materials, engineering plastic substitutes and the like.

[0002]

2. Description of the Related Art Polypropylene is generally inexpensive,
And taking advantage of its features such as light weight, transparency, mechanical strength, heat resistance, chemical resistance, etc.
Widely used for industrial materials such as electronic components, various packaging materials, and the like. In recent years, with the enhancement of functions and cost reduction of products, there is a strong demand for improved properties of these materials.

As a method for improving the rigidity, impact resistance, heat resistance, etc. of polypropylene, for example, a method of blending ethylene-propylene rubber and a nucleating agent with an ethylene-propylene block copolymer (Japanese Patent Publication No. 60-3420, etc.) ) Or a method of blending an ethylene-propylene rubber, an ethylene copolymer and an inorganic filler (JP-A-4-275351, JP-A-5-5051, JP-A-5-98097, JP-A-5-98098) Etc.) have been proposed.

[0004]

However, although the above methods all improve some of the characteristics, they are still insufficient in heat resistance and rigidity.
The present invention has been made in view of such circumstances, and has as its object to provide a propylene resin composition having excellent rigidity, impact resistance, heat resistance, and surface hardness.

[0005]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that the above object can be achieved by a propylene block copolymer having specific physical properties, and based on this finding, the present invention has been achieved. Was completed. That is, the present invention provides a polypropylene part (a) having the following physical properties (i) to (iv); (i) a xylene-extractable insoluble part at 25 ° C of 99.0% by weight or more; and (ii) an isotactic pentad fraction. 98.0%
(Iii) Isotactic average chain length of 500 or more (iv) Total amount of fractions having an isotactic average chain length of 800 or more by column fractionation 10
% By weight or more Copolymer part of propylene and ethylene and / or α-olefin having 4 to 12 carbon atoms satisfying all of the following conditions (v) to (viii) (b) (v) Average propylene by two-site model Content (FP)
20 to 80 mol% (vi) 2 sites copolymer produced in the active sites of polymerization preferentially propylene in the model propylene content _(P P) 65 to 90 mol% of _{(P H) (vii) P} H is co Proportion in polymer (P _f1 ) 0.4
0-0.90 (viii) Blockability by two-site model (CSD)
The present invention provides a propylene block copolymer consisting of 1.8 to 5.0. Hereinafter, the present invention will be described in detail.

The propylene block copolymer (hereinafter referred to as “BPP”) in the present invention comprises a polypropylene part (a) and a copolymer part (b) of propylene and ethylene and / or an α-olefin having 4 to 12 carbon atoms. ). The BPP of the present invention requires that the polypropylene part (a) produced by the first-stage reaction has the following physical properties.

That is, (i) the xylene-extracted insoluble portion at 25 ° C. (hereinafter referred to as “XI”) is at least 99.0% by weight, preferably at least 99.5% by weight, more preferably at least 99.7% by weight. It is. XI is 99.0% by weight
If it is less than 1, rigidity and heat resistance are inferior. The measurement of XI was based on a method in which polypropylene was once dissolved in ortho-xylene at 135 ° C., and then cooled to 25 ° C. to precipitate a polymer.

Further, (ii) the isotactic pentad fraction (hereinafter referred to as “IP”) must be at least 98.0%, preferably at least 98.5%, particularly preferably 99.0%.
The above is preferable. If the IP is less than 98.0%, rigidity and heat resistance are inferior, which is not preferable.

The IP is an isotactic fraction in pentad units in a polypropylene molecular chain measured by nuclear magnetic resonance ( ¹³ C-NMR) spectroscopy using isotope carbon. The measurement method is described in A. Zambelli; Macromol
ecules, 6, 925 (1973) , the 8, 687 (1975) and ibid 13, 267
(1980).

(Iii) The average isotactic chain length (hereinafter referred to as "N") is 500 or more, preferably 700
Above, particularly preferably 800 or more. N
Is less than 500, the rigidity and heat resistance are poor. In addition, N represents the average length of the isotactic portion of the methyl group in the polypropylene molecule, and the measurement method is described in JCRandall; Polymer Sequense Distribution, Academic.
mic Press, New York, 1977, Chapter 2). Specifically, polypropylene is 1,2,
130 ° C. in a mixed solvent of 4-trichlorobenzene / deuterated benzene so that the polymer concentration becomes 10% by weight.
Heat to dissolve. This solution is placed in a 10 mmφ glass sample tube, and the ¹³ C-NMR spectrum is measured in the same manner as in IP. FIG. 1 shows an example of this spectrum diagram.
FIG. 1A is a spectrum of a methyl group region in polypropylene, and b is an enlarged view of the spectrum.
The spectrum is measured using a pentad unit, that is, five adjacent methyl groups as one unit, and the absorption peak varies depending on the isotacticity of the methyl group (there are ten structural types such as mmmm and mmmr). FIG.
B shows the correspondence between the absorption peak and the isotacticity.

On the other hand, Shan-Nong et al;
There is a two-site model described in olymer Journal, vol. 15, No. 12, p859-868 (1983). That is, it is assumed that there are two kinds of active species at the time of polymerization: a catalyst side and a polymer terminal, and the catalyst side is a catalyst controlled polymerization, and the other is a terminal controlled polymerization (for details, see Junji Furukawa; Essence of molecules and topics 2, “Polymer synthesis”, P7
3 (published by Kagaku Doujin Inc. (1986)).

[0012] According to the above literature, the two-site model is, in the end, α: Probability that D-form and L-form are added to the polymerization terminal by catalyst-controlled polymerization (enantiomorphic process), that is, the degree of disorder in the isotactic chain. Σ: Probability of the formation of a meso-form which is the same as the polymerized end by the terminal dominant polymerization (Bernoulli process) ω: The ratio of α-sites Theory of ten isotactic intensities with different isotacticity in pentad units Can be calculated. Then, α, σ, and ω are determined by the least squares method so that the intensity measured by NMR and the theoretical intensity match, and each pentad unit is determined by the following equation.

[0013]

[Table 1]

Next, a formula for defining the average chain length (N) described in the above-mentioned article of J C. Randall; N = the number of chains in the meso form / the number of units in the meso form, is actually obtained by the following equation. be able to. N = 1 + (A ₁ + A ₂ + A ₃ ) /0.5 (A ₄ + A ₅ +
A ₆ + A ₇ )

(Iv) The total amount of fractions having an average isotactic chain length (hereinafter referred to as “N _f ”) of 800 or more in each fraction by column fractionation is 10% by weight of the whole.
It is necessary to be at least 30% by weight, particularly preferably at least 50% by weight. _If the total amount of _Nf is 800 or more is less than 10% by weight, the effect of improving rigidity, surface hardness and heat resistance is poor.

Here, the column fractionation method means that the above-mentioned xylene-extracted insoluble portion is dissolved in para-xylene at a temperature of 130 ° C., and then celite is added. Then, a column is filled with slurry-like celite, the temperature is gradually increased from 30 ° C. to 2.5 ° C. using para-xylene as a developing solution, and polypropylene is fractionated. See Masahiro Kakugo et al; Macromolecules, vo
l.21, p314-319 (1988). N _f prep polypropylene is determined using the measurement method of the N.

The BPP of the present invention requires that the propylene-α-olefin copolymer (b) produced in the second-stage reaction satisfy all of the following conditions. Here, a two-site model of a propylene-α-olefin copolymer will be described by taking a propylene-ethylene copolymer as an example. FIG. 2 shows an example of a nuclear magnetic resonance (< ¹³ > C-NMR) spectrum of a propylene-ethylene copolymer using isotope carbon. In the spectrum, ten peaks shown in (1) to (10) appear due to differences in the chain distribution (the arrangement of ethylene and propylene). The name of this chain is Carman, C, J, et a
l; Macromolecules, Vol. 10, p536-544 (1977), the names of which are shown in FIG. Such a chain can be expressed as a reaction probability (P) assuming a reaction mechanism of copolymerization.
The relative intensity of the peak in (10) can be expressed as a probability equation by Bernoulli statistics with P as a parameter.

For example, (1) In the case of Sαα, assuming that the propylene unit is symbol p and the ethylene unit is symbol e, the chains that can take these are [pppp], [ppee], [epp].
e], and these are referred to as reaction probabilities (P), respectively.
And add them together. The remaining peaks (2) to (10) can be obtained by formulating a formula in the same manner and optimizing P so that these ten formulas and the actually measured peak intensities become closest. .

The two-site model is a model that assumes this reaction mechanism, and is described in HNCHENG; Journal of Applied Polymer.
Sience, Vol. 35, p. 1639-1650 (1988). That is, in a model in which propylene and ethylene are copolymerized using a catalyst, the propylene content (P _P ) of the copolymer (P _H ) generated at the active site where propylene is preferentially polymerized.
And the propylene content ( _PP ') of the copolymer produced at the active site where ethylene and ethylene are preferentially polymerized.
Assuming that the proportion (P _f1 ) of _H in the copolymer is a parameter, a probability equation shown in Table 2 below is obtained.

[0020]

[Table 2]

In order that the relative intensity of the above-mentioned ¹³ C-NMR spectrum and the probability equation shown in Table 2 match, P _P ,
It is determined by optimizing three parameters P _P ′ and P _f1 .

(V) Average propylene content (FP) of the present invention
Is obtained by the following equation using the above three parameters. _{FP = P P × P f1 +} P P '× (1-P f1) FP sought (mol%) The above formula is 20 to 80 mol%, preferably 25 to 75 mol%, more preferably 3
0-70 mol%. If the FP is less than 20 mol%, the appearance of the molded article is significantly reduced. On the other hand, if it exceeds 80 mol%, the impact resistance is undesirably reduced.

Further, among the above parameters, (vi) P _P
Is 65 to 90 mol%, preferably 68 to 88 mol%, and particularly preferably 70 to 85 mol%. P _P is 6
If it is less than 5 mol%, the rigidity and heat resistance decrease. on the other hand,
If it exceeds 90 mol%, the impact resistance is impaired, which is not preferred.

(Vii) P _f1 is 0.40 to 0.90
And 0.45 to 0.85 is preferable, and particularly preferably 0.1 to 0.85.
48-0.82 is preferred. If P _f1 is less than 0.40, the rigidity and heat resistance decrease. On the other hand, if it exceeds 0.90, the impact resistance is impaired, which is not preferable.

Finally, (viii) Blocking property (CSD) refers to the reactivity ratio between ethylene and propylene, which is defined by the Society of Polymer Association, “Copolymerization 1 Reaction Analysis,” pp. 5-1.
3. Followed the method published by Baifukan (1975). That is, it is expressed by the following equation using the intensity ratio (Ri) of each peak in the spectrum of FIG. CSD = [(0.5 × R7 + 0.25 × R6 + 0.5 × R3) × R1] /
[0.5 × (R2 + R3)] ^{2 The} CSD obtained by the above equation is 1.8 to 5.0, and 2.0
-4.5 is preferable, and especially 2.5-4.0 is preferable. If the CSD is less than 1.8, the rigidity and heat resistance decrease. On the other hand, if it exceeds 5.0, the impact resistance at low temperatures is impaired, which is not preferable.

Propylene-α in the BPP of the present invention
The proportion of the olefin copolymer (b) is 3 to 50% by weight, preferably 5 to 45% by weight, particularly preferably 10 to 40% by weight;
% By weight is preferred. If the proportion of (b) is less than 3% by weight, the impact strength decreases. On the other hand, if it exceeds 50% by weight, rigidity and heat resistance are impaired, which is not preferred.

The polymerization of the BPP of the present invention is carried out in the presence of an inert hydrocarbon such as hexane, heptane or kerosene or a liquefied α-olefin solvent such as propylene.
Temperature conditions are room temperature to 130 ° C., preferably 50 to 90 ° C., and pressure is 2 to 50 ° C. by a gas phase polymerization method without solvent.
It is performed under the condition of kg / cm ² . As the reactor in the polymerization step, those usually used in the technical field can be appropriately used.For example, a continuous system, a semi-batch system, a batch system using a stirred tank reactor, a fluidized bed reactor, and a circulation reactor can be used. Either method may be used. Specifically, it is obtained by using a known multi-stage polymerization method. That is, a method in which propylene is polymerized in the first-stage reaction, and then propylene and an α-olefin are copolymerized in the second-stage reaction. For example, JP-B-36-15284 and JP-B-38-14834 JP-A-53-35788, JP-A-53-35789, JP-A-56-55416, and the like.

The BPP of the present invention cannot be obtained with a known Ziegler-Natta type catalyst such as a titanium trichloride-based catalyst or a magnesium chloride-supported titanium catalyst. Examples of the catalyst for obtaining the BPP of the present invention include a magnesium compound,
A solid catalyst comprising a titanium compound, a halogen-containing compound and an electron-donating compound as essential components is further treated with a general formula: TiXa
Yb (where X is a halogen atom of Cl, Br, I, Yb
Represents an electron donating compound, a represents 3 or 4, and b represents an integer of 3 or less.), And then washed with a halogen-containing compound and further washed with a hydrocarbon. And a polymerization catalyst.

Ti Xa in the above formula is, for example, RPSCo
utts, et al, Advan.Organometal.Chem., 9 , 135 (1970), 4th edition, New Experimental Chemistry Course 17 Inorganic and chelate complexes The Chemical Society of Japan Maruzen (1991) p.35, HKKakkoen, et al, J. Organ
As described in Omet. Chem., 453 , 175 (1993), it is generally known that a complex easily forms with an electron donating compound.

X is a halogen atom of Cl, Br, I, of which Cl is preferred. a is 3 or 4, but preferably 4. Y generally includes an oxygen-containing compound, a nitrogen-containing compound, a phosphorus-containing compound, a sulfur-containing compound, and the like. Examples of the oxygen-containing compound include alcohols, ethers, esters, acid halides, and acid anhydrides. These electron donating compounds may be used alone or in combination of two or more. Of these, preferred are esters, and particularly preferred are phthalic esters. B of Y is a
When b is 3, b is preferably 1 to 3, and when a is 4, 1 or 2 is preferable. Particularly preferable is when a is 4 and b is 1.

The BPP of the present invention is further improved in rigidity, heat resistance and impact strength by adding a nucleating agent. The nucleating agent refers to a substance which is added to a crystalline resin in the synthetic resin field and has an effect of growing a crystal as a nucleus, and includes various substances. Specific examples include, for example, metal salts of carboxylic acids, dibenzylidene sorbitol derivatives, phosphate metal salts, and inorganic fillers such as talc and calcium carbonate. These nucleating agents are 1
Seeds may be used, or two or more kinds may be used in combination.

The addition amount of the nucleating agent is generally 0.05 to 0.5% by weight, excluding the inorganic filler, and preferably 0.1 to 0.5% by weight.
08-0.4% by weight, especially 0.1-0.35% by weight
Is preferred. On the other hand, inorganic fillers such as talc
30% by weight, preferably 7 to 28% by weight, particularly 9% by weight.
~ 25% by weight is preferred. The composition of these nucleating agents is
Mix each component using a known mixing method, for example, a ribbon blender, a tumbler, a Henschel mixer, etc.
Further, it is obtained by melt-mixing using a kneader, a mixing roll, a Banbury mixer, an extruder, or the like. The temperature at the time of melt mixing is usually 170 to 280 ° C, preferably 190 to 260 ° C. The resulting composition is
By a known melt molding method and compression molding method, a film,
It can be formed into sheets, tubes, bottles and the like and used alone or as a laminate by laminating other materials.

As a lamination method, a so-called dry lamination molding method, a co-extrusion lamination method, a co-extrusion method, a co-extrusion method in which other thermoplastic resins are laminated using an adhesive such as a polyurethane-based, polyester-based or polyacryl-based adhesive. Examples include an injection molding method and a co-extrusion pipe molding method. The multilayer laminate thus obtained can be formed into a molded body by a method of reheating and stretching using a molding method such as vacuum molding, air pressure molding, or stretch blow molding.

Further, the BPP of the present invention may contain additives commonly used by those skilled in the art, such as antioxidants, weathering stabilizers, antistatic agents, lubricants, antiblocking agents, antifogging agents,
Pigments, plasticizers, softeners and the like may be appropriately compounded within a range that does not impair the purpose of the present invention.

[0035]

The present invention will be described in more detail with reference to the following examples. In addition, the measuring method of each physical property is shown below. [MFR] A melt indexer manufactured by Takara was used according to JIS K7210. [Ethylene content] CJCarman et al; Macromolecule
s, 10, 537 was based on ¹³ C-NMR method described in (1977). [Flexural modulus] Based on JIS K7203. [Izod impact strength] Based on JIS K7110,
Measured with notch. [Dropping weight impact strength] According to ASTM D3029-78, the weight was dropped from a height of 1 m and the load of the weight was 100
The load at which 50% of the 20 test pieces were broken was determined while changing the load for each g. The temperature was measured at -20 ° C. [Load deflection temperature] In accordance with JIS K7207B method,
The measurement was performed under a load of 4.6 kg.

[Rockwell hardness] JIS K7202
Was measured on a scale R according to Also, the BPP used
The production example of is shown below. (A) Preparation of solid catalyst 56.8 g of anhydrous magnesium chloride was added to anhydrous ethanol 1
00g, Idemitsu Kosan Vaseline Oil (CP15N) 5
00ml and silicone oil (KF
96) 12 ml of a 500 ml mixed solution was added under a nitrogen atmosphere.
Completely dissolved at 0 ° C. This mixture is made by T
Using a K homomixer, the mixture was stirred at 120 ° C. and 3000 rpm for 3 minutes. It was then transferred into 2 liters of anhydrous heptane with cooling, maintaining the temperature below 0 ° C., while maintaining stirring. The obtained white solid was sufficiently washed with anhydrous heptane and dried under vacuum at room temperature. White solid 3 obtained
0 g was suspended in 200 ml of anhydrous heptane, and 500 ml of titanium tetrachloride was added dropwise with stirring at 0 ° C. over 1 hour. Next, when heating was started and the temperature reached 40 ° C., 4.96 g of diisobutyl phthalate was added, and the temperature was reduced to about 100 ° C. by about 1 hour.
Raised in time. After reacting at 100 ° C. for 2 hours, a solid portion was collected by hot filtration. 500 ml of titanium tetrachloride was added to the obtained solid portion, and the mixture was reacted at 120 ° C. for 1 hour with stirring.
7 times with 1 liter of hexane at room temperature.
Washed three times with liters.

(B) TiCl ₄ [C ₆ H ₄ (COO ⁱ C
Preparation of ₄ H ₉ ) ₂ ] To a solution of 19 g of titanium tetrachloride in 1 liter of hexane, 27.8 g of diisobutyl phthalate was added dropwise over about 30 minutes while maintaining 0 ° C. After completion of the dropwise addition, the temperature was raised to 40 ° C., and the reaction was performed for 30 minutes. After the completion of the reaction, a solid portion was collected and washed five times with 500 ml of hexane to obtain the desired product.

(C) Preparation of polymerization catalyst component 20 g of the solid catalyst obtained in the above (A) was mixed with 300 parts of toluene.
of the TiC obtained in (b) above at 25 ° C.
5.2 g of l ₄ [C ₆ H ₄ (COO ⁱ C ₄ H ₉ ) ₂ ] was applied for 1 hour to be supported. After the loading was completed, a solid portion was collected by hot filtration, and 300 ml of toluene and 10 m of titanium tetrachloride were collected.
and washed with stirring at 90 ° C. for 1 hour. A solid portion was collected by hot filtration. Thereafter, the reaction product was washed five times with 500 ml of 90 ° C. toluene and 500 ml of hexane at room temperature.
And washed three times.

Prepolymerization Under an atmosphere of nitrogen, 500 ml of n-heptane, 6.0 g of triethylaluminum and 3.9 of dicyclopentyldimethoxysilane were placed in a 3 liter autoclave.
g, and 10 g of the polymerization catalyst component obtained in (c) above were charged, and the mixture was stirred for 5 minutes in a temperature range of 0 to 5 ° C. next,
Propylene is supplied into the autoclave so that 10 g of propylene is polymerized per 1 g of the polymerization catalyst component, and 0 to 5
Prepolymerization was performed for 1 hour in a temperature range of ° C. The obtained prepolymerized solid catalyst component was washed three times with 500 ml of n-heptane and used for the following main polymerization.

Main polymerization (1) First-stage polymerization: 2.0 g of the prepolymerized solid catalyst prepared by the above method and triethylaluminum 1 in a 60-liter autoclave with a stirrer under a nitrogen atmosphere.
1.4 g, dicyclopentyldimethoxysilane 6.84
g, then 18 kg of propylene, hydrogen was charged so as to be 13000 mol ppm based on propylene,
The temperature was raised to 75 ° C., and polymerization was performed for 1 hour. Thereafter, unreacted propylene was removed to terminate the polymerization. After the reaction,
The reaction product was sampled.

(2) Second-stage polymerization: After completion of the first-stage polymerization, liquid propylene was removed, and a mixed gas of ethylene / propylene = 40/60 (molar ratio) 2.2 Nm ³ / hour at a temperature of 75 ° C. and hydrogen Copolymerization was performed at a feed rate of 20 Nl / hour for 40 minutes. After the completion of the polymerization, the unreacted gas was removed to terminate the polymerization. As a result, a propylene-ethylene block copolymer (hereinafter referred to as “BPP1”) 8.6 having an ethylene content of 9.5% by weight and an MFR of 16.9 g / 10 min.
kg.

Similarly, the amount of hydrogen charged during the first stage polymerization,
The polymerization time and the amount of ethylene in the second-stage polymerization were adjusted so that the ethylene content was 10.8% by weight and the MFR was 7.3 g / 1.
A propylene-ethylene block copolymer (hereinafter referred to as “BPP2”) having 0 minutes and an ethylene content of 6.
A propylene-ethylene block copolymer having 1% by weight and an MFR of 26.8 g / 10 minutes (hereinafter referred to as “BPP3”)
). In addition, during the second stage polymerization, the ethylene content was 7.8% by weight, the butene-1 content was 0.7% by weight, and the MFR was 15. A propylene-ethylene block copolymer (hereinafter referred to as "BPP4") having a weight of 3 g / 10 minutes was obtained.

Further, the following two types of BPs were used for comparison.
P was used. 6.0 g of AA type titanium trichloride manufactured by Tosoh Akzo, 23.5 g of diethylaluminum chloride
Was used as a catalyst component, hydrogen was charged to 18 kg of propylene and 8000 mol ppm based on propylene, the temperature was raised to 70 ° C., and polymerization was performed in the same manner as in BPP1. As a result, the ethylene content was 9.8. % By weight and MFR
BPP1 was 18.2 g / 10 min (hereinafter referred to as “BPP5”), and the catalyst prepared in the above (a) was used, and the amount of hydrogen in the first-stage polymerization was changed to 9,300 mol ppm. The polymerization was carried out in the same manner as described above, and the ethylene content was 10.1% by weight and the MFR was 18.4 g / 1.
What was 0 minutes (hereinafter referred to as "BPP6") was obtained.

With respect to the polypropylene portion sampled at the end of the first-stage polymerization of the above copolymer, XI, IP,
N and _Nf were measured. Table 2 shows the results. In addition, the measurement conditions of IP are as follows. Measuring instrument JNM-GSX400 manufactured by JEOL Co., Ltd. Measurement mode: Proton decoupling method Pulse width: 8.0 μs Pulse repetition time: 3.0 s Integration frequency: 20,000 times Solvent: 1,2,4-trichlorobenzene / heavy benzene Mixed solvent (75/25% by weight) Internal circulation: hexamethyldisiloxane Sample concentration: 300 mg / 3.0 ml Solvent Measurement temperature: 120 ° C

[0045]

[Table 3]

The FP, P _P , P _f1 and CSD of each ethylene-propylene copolymer part obtained in the second step were analyzed by NMR spectrum and two-site model analysis.
I asked. Table 4 shows the results.

[0047]

[Table 4]

Further, aluminum pt-butyl benzoate was used as a nucleating agent.

Examples 1 to 7 and Comparative Examples 1 to 4 BPP whose type and amount are shown in Table 5 and 0.05% by weight of nucleating agent and di-t-butyl-p-cresol as a stabilizer, 0.10% by weight of pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] and 0.10% by weight of calcium stearate are blended, and a super mixer manufactured by Kawada Manufacturing Co., Ltd. (SMV20 type) and pelletized using a twin screw extruder (AS30 type) manufactured by Nakatani Machinery Co., Ltd. Each of the obtained pellets was heated to a temperature of 22 using an injection molding machine (IS-170FII) manufactured by Toshiba Machine Co.
Each test piece was prepared at 0 ° C. and a mold cooling temperature of 50 ° C. The obtained test piece was placed in a constant temperature room at a relative humidity of 50% and a temperature of 23 ° C for 2 hours.
After standing for one day, the flexural modulus, Izod impact strength (with notch), falling weight impact strength, deflection temperature under load and Rockwell hardness were measured. Table 5 shows the obtained results.

[0050]

[Table 5]

[0051]

The resin composition of the present invention is excellent in rigidity, impact resistance, heat resistance and surface hardness, and is particularly useful for automobile parts, electric / electronic parts, packaging materials and the like.

[Brief description of the drawings]

FIG. 1 is an example of a nuclear magnetic resonance spectrum in the methyl region of polypropylene.

FIG. 2 is an example of a nuclear magnetic resonance spectrum of an ethylene-propylene copolymer.

FIG. 3 is a view showing names of carbons derived from a chain distribution in polyolefin.

[Explanation of symbols]

 a: Spectrum diagram b: Enlarged view of a

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-5-194685 (JP, A) JP-A-4-279617 (JP, A) JP-A-8-81529 (JP, A) JP-A-8-815 73547 (JP, A) JP-A-6-329737 (JP, A) JP-A-8-12717 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) C08F 297/06-297 / 08 C08F 4/60-4/70 C08L 53/00

Claims (3)

(57) [Claims] 1. A polypropylene part (a) having the following physical properties (i) to (iv): 50 to 97% by weight; (i) a xylene-extractable insoluble part at 25 ° C. of 99.0% by weight or more; Tic pentad fraction 98.0%
(Iii) Isotactic average chain length of 500 or more (iv) Total amount of fractions having an isotactic average chain length of 800 or more by column fractionation 10
50% to 3% by weight (v) 2 A copolymer part (b) of propylene and ethylene and / or an α-olefin having 4 to 12 carbon atoms that satisfies all of the following conditions (v) to (viii). Average propylene content (FP) by site model
20 to 80 mol% (vi) 2 sites copolymer produced in the active sites of polymerization preferentially propylene in the model propylene content _(P P) 65 to 90 mol% of _{(P H) (vii) P} H is co Proportion in polymer (P _f1 ) 0.4
0-0.90 (viii) Blockability by two-site model (CSD)
A propylene block copolymer consisting of 1.8 to 5.0. 2. A solid catalyst comprising a magnesium compound, a titanium compound, a halogen-containing compound and an electron-donating compound as essential components, further comprising a general formula: Ti Xa .Yb (wherein
X is a halogen atom of Cl, Br, I, Y is an electron donating compound, a is 3 or 4, and b is an integer of 3 or less.) The method for producing a propylene block copolymer according to claim 1, which is obtained by polymerization using an improved polymerization catalyst obtained by washing and further washing with a hydrocarbon. 3. A propylene block copolymer resin composition comprising the propylene block copolymer according to claim 1 and at least 0.05 to 30% by weight of a nucleating agent.