JPH09278846A - High fluidity ethylene-propylene block copolymer - Google Patents

Abstract

(57) [Summary] (Modified) [PROBLEMS] An ethylene-propylene block copolymer having excellent rigidity and tensile properties, and having good melt fluidity. SOLUTION: A propylene homocopolymer or propylene and ethylene or an α-olefin having 4 or more carbon atoms is 1
A crystalline polypropylene portion copolymerized at a mol% or less,
The composition has a random copolymer part in which the composition ratio of ethylene and propylene is ethylene / propylene = 10/90 to 50/50 by weight ratio, and (1) 1 of the crystalline polypropylene part
Intrinsic viscosity [η] _{P of} 35 ° C tetralin solution is 0.5 to
0.8 dl / g, (2) the ethylene-propylene random copolymer portion has a 135 ° C. tetralin solution having an intrinsic viscosity of 1.5 to 8.0, and (3) the ethylene-propylene random copolymer portion is the whole polymer. 1 to 40% by weight, and (4) a melt flow index (MI) of 70 to 10
An ethylene-propylene block copolymer that is 00 g / 10 minutes.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an ethylene-propylene block copolymer having excellent fluidity, rigidity and tensile properties.

[0002]

2. Description of the Related Art Polypropylene (including ethylene-propylene block copolymer) has excellent properties and is relatively inexpensive, so that it can be used for daily necessities, household electrical appliances, automobile parts,
It is widely used for industrial parts, but the size of molded products increases,
Thinning is progressing along with weight reduction. Therefore, the rigidity,
A polypropylene or polypropylene resin composition having excellent heat resistance, impact resistance and tensile properties has been demanded. Conventionally, as a method of improving melt fluidity, a method of adding a small amount of an organic peroxide to polypropylene having a low melt fluidity or a composition thereof and performing heat treatment is known. However, the polypropylene obtained by such a method has a remarkable decrease in rigidity, a problem of odor caused by heat treatment, and a problem such as generation of a flow mark on the surface of the injection molded article. Therefore, development of polypropylene excellent in rigidity, tensile properties, melt fluidity, etc. without the need for such heat treatment is strongly desired.

[0003]

SUMMARY OF THE INVENTION In view of such a state of the art, it is an object of the present invention to provide an ethylene-propylene block copolymer having excellent rigidity and tensile properties and good melt flowability.

[0004]

The present invention provides a composition of propylene homocopolymer or a crystalline polypropylene portion obtained by copolymerizing propylene and ethylene or an α-olefin having 4 or more carbon atoms in an amount of 1 mol% or less, and ethylene and propylene. The weight ratio is ethylene / propylene = 10/90 to 50
/ 50 ethylene glycol-propylene random copolymer portion, (1) crystalline polypropylene portion of 135 ℃
Intrinsic viscosity [η] _{P of} tetralin solution is 0.5-0.8d
1 / g, gel permeation chromatography (G
The weight average molecular weight (Mw) / number average molecular weight (Mn) ratio by the PC method is 5 or less, the 20 ° C xylene-soluble part (CXS) is 1.0% by weight or less, and (2) ethylene-propylene. The 135 ° C. tetralin solution of the random copolymer part has an intrinsic viscosity [η] _EP of 1.5 to 8.0 dl / g, and (3) the ethylene-propylene random copolymer part is 1 to 40% by weight of the total polymer. %, And (4) the melt flow index (MI) is 70 to 1000 g / 10.
Is an ethylene-propylene block copolymer.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The ethylene-propylene block copolymer in the present invention is a propylene homopolymer or 1 mol of propylene and ethylene or an α-olefin having 4 or more carbon atoms (eg, butene-1, hexene-1). % Or less of the copolymerized polypropylene part, and the composition of ethylene and propylene is ethylene / propylene = 1 by weight ratio.
It has an ethylene-propylene random copolymer part of 0/90 to 50/50 and contains the ethylene-propylene random copolymer part in an amount of 1 to 40% by weight based on the whole polymer.

The block copolymer of the present invention is usually obtained by polymerizing a monomer in two steps in the presence of a Ziegler-Natta catalyst in combination with titanium trichloride and an alkylaluminum compound. It is preferable to use a catalyst composed of a contained solid catalyst component (composite of titanium trichloride and magnesium), a trialkylaluminum compound and an electron-donating organic compound.

A method for producing this catalyst is disclosed in, for example, Japanese Patent Laid-Open No.
-319508, Japanese Patent Laid-Open No. 61-218606
It is described in detail in the newsletter. That is, (A) Si-O bond
Coexistence of silicon compounds and ester compounds having
To the general formula Ti (OR¹)_nX _4-n(R¹Has 1 to 2 carbon atoms
0 hydrocarbon group, X is a halogen atom, n is 0 <n ≦ 4
It is an integer. ), The titanium compound represented by
The solid product obtained by reduction with a nesium compound is
Treated with tellurium compound, ether compound and titanium tetrachloride
A trivalent titanium compound-containing solid catalyst component obtained by
(B) Organoaluminum compound, and (C) electron donation
It is a catalyst composed of a polar compound.

The titanium compound used in the synthesis of the solid catalyst component (A) is represented by the above general formula, wherein R ¹ is an alkyl group having 2 to 18 carbon atoms and an ant having 6 to 18 carbon atoms. Group is preferred. Examples of the halogen atom represented by X include chlorine, bromine and iodine. Among them, chlorine is particularly preferable. As the value of n of the titanium compound represented by the above general formula, 0 <n ≦ 4, preferably
2 ≦ n ≦ 4, particularly preferably n = 4.

Used for the synthesis of the above solid catalyst component (A)
As the organosilicon compound having a Si—O bond,
Examples include those represented by the following general formula. Si (OR
^Two) _mR^Three _4-m, R^Four(R^FiveSiO)_pSiR⁶ _ThreeOr
(R⁷ _TwoSiO)_q(R here^TwoIs carbonized with 1 to 20 carbon atoms
Hydrogen radical, R^Three, R^Four, R^Five, R⁶, And R⁷Is the carbon number
Is a hydrocarbon group or hydrogen atom of 1 to 20, m is 0 <m ≦ 4
Is a positive number, p is an integer from 1 to 1000, and q is from 2 to 1000.
It is an integer. As a specific example of the organosilicon compound, tetra
Methoxysilane, dimethyldimethoxysilane, dietoki
Cydiethylsilane, diethoxydiphenylsilane, tri
Ethoxyphenylsilane, cyclohexyl ethyl dime
Examples include toxysilane and phenyltrimethoxysilane.
Among these organosilicon compounds, preferred ones are
General formula Si (OR^Two)_mR^Three _4-mIs represented by
Compound, preferably 1 ≦ m ≦ 4 in this formula
In particular, a tetraalkoxylane compound having m = 4 is preferable.
Yes.

The organomagnesium compound used in the synthesis of the above solid catalyst component (A) is magnesium-
Any type of organomagnesium compound containing a carbon bond can be used. In particular, the general formula R ⁸ MgX (R ⁸ has 1 carbon atom)
~ 20 hydrocarbon groups, X is halogen. ) And the general formulas R ⁹ , R ¹⁰ Mg (R
⁹ and R ¹⁰ are hydrocarbon groups having 1 to 20 carbon atoms. A dialkyl magnesium compound or a diaryl magnesium compound represented by the formula (1) is preferably used. Here, R ⁹ and R ¹⁰ may be the same or different.

Examples of the ester compound used in the synthesis of the above solid catalyst component (A) include monocarboxylic acid compounds such as aliphatic carboxylic acid esters, olefinic carboxylic acid esters, alicyclic carboxylic acid esters and aromatic carboxylic acid esters, and polyvalent compounds. Carboxylic acid ester of. Among these ester compounds, olefin carboxylic acid esters such as methacrylic acid esters and maleic acid esters, and phthalic acid esters are preferable, and diesters of phthalic acid are particularly preferable.

As the ether compound, dialkyl ethers such as diethyl ether, di-n-propyl ether, diisopropyl ether, dibutyl ether, diamyl ether and methyl-n-butyl ether are preferable, and di-n-butyl ether, di-n-butyl ether and di-n-butyl ether are particularly preferable. Isoamyl ether is preferred.

The solid catalyst component (A) is obtained by treating a solid product obtained by reducing a titanium compound with an organomagnesium compound in the presence of an organosilicon compound and an ester compound with an ester compound, and then adding ether. It is synthesized by treating with a mixture of a compound and titanium tetrachloride, or treating with a mixture of an ether compound, titanium tetrachloride and an ester compound. All of these synthesis reactions are performed under an atmosphere of an inert gas such as nitrogen or argon. The reduction reaction temperature is
The temperature range is −50 ° C. to 70 ° C., preferably −30 ° C. to 50 ° C., and particularly preferably −25 ° C. to 35 ° C.

The organoaluminum compound as the component (B) has at least one aluminum-carbon bond in the molecule and has the following general formulas R ¹¹ r AlY _3-r and R ¹² R ¹³ Al-O.
—AlR ¹⁴ R ¹⁵ (R ^{11 to} R ¹⁵ represent a hydrocarbon group having 1 to 20 carbon atoms, Y halogen, hydrogen or an alkoxy group, and r is a positive number represented by 2 ≦ r ≦ 3. ) Is represented. Specific examples of the organic aluminum compound, triethyl aluminum, triisobutyl aluminum, trialkyl aluminum such as trihexyl aluminum, diethyl aluminum halide, dialkyl aluminum halide such as diisobutyl aluminum halide, a mixture of triethyl aluminum and dialkyl aluminum halide, tetraethyl di Examples thereof include alkylalumoxane such as alumoxane and tetrabutyl dialumoxane.

Of these organoaluminum compounds,
Trialkylaluminum, mixtures of trialkylaluminum and diethylaluminum chloride and tetraethyldialumoxane are preferred.

The amount of the organoaluminum compound used is 0.5 to 1 per mol of titanium atom in the solid catalyst component (A).
Although it can be selected from a wide range such as 000 mol, a range of 1 to 600 mol is particularly preferable.

The electron-donating compound of the component (C) includes alcohols, phenols, ketones, aldehydes, carboxylic acids, esters of organic or inorganic acids, ethers, and acids. Examples include oxygen-containing electron donors such as amides and acid anhydrides, and nitrogen-containing electron donors such as ammonia, nitriles, and isocyanates. Of these electron donors, esters and ethers of inorganic acids are preferably used.

An organoaluminum compound of component (B),
The ratio of the titanium compound to the magnesium compound composite can be selected in the range of 3/1 to 20/1. Also Si
The ratio of the silane compound having an —O bond and the complex of the titanium compound and the magnesium compound is 1/10 to 1/2.
It can be selected within the range of (mol / mol).

The ethylene-propylene block copolymer of the present invention comprises the following components (I) and (II). (I) Crystalline polypropylene part (sometimes called P part) (1) Intrinsic viscosity [η] _{P of} 135 ° C. tetralin solution is 0.5 to 0.8 dl / g, preferably 0.6 to 0.8 d
1 / g, and (2) weight average molecular weight (MPC) by gel permeation chromatography (GPC) method.
w) / number average molecular weight (Mn) ratio, Q value is 5 or less,
It is preferably 3 to 4.5, and (3) occupies 99 to 60% by weight of the total amount of the copolymer, and the xylene-soluble portion at 20 ° C. is 1.0% by weight or less, preferably 0.5% by weight or less. Is. (II) Ethylene-propylene random copolymer part (sometimes referred to as EP part) (1) Intrinsic viscosity [η] _{EP in} 135 ° C. tetralin is 1.5 to 8.0 dl / g, preferably 1.8. ~ 7.5d
1 / g, (2) ethylene and propylene composition is 1 by weight ratio
It is 0/90 to 50/50 (weight ratio), and occupies 1 to 40% by weight of the total amount of the copolymer (3).

This ethylene-propylene block copolymer is produced by the slurry polymerization method or the gas phase polymerization method in the two steps of the above-mentioned parts (I) and (II), and the slurry polymerization method is preferred. If [η] _{P in} the portion (I) is smaller than 0.5 dl / g, the mechanical strength will decrease,
If it exceeds 0.8 dl / g, the melt fluidity of the ethylene-propylene block copolymer will decrease. If the Q value exceeds 5, the rigidity and tensile properties of the ethylene-propylene block copolymer deteriorate. If the intrinsic viscosity [η] _EP of the portion (II) is less than 1.5 dl / g, the rigidity and impact resistance are low, and if it exceeds 8.0 dl / g, the melt fluidity decreases, and the composition constituents Poor dispersion results in poor tensile properties and impact resistance. Further, if the ethylene content in the part (II) (ethylene-propylene random copolymer) is less than 10% by weight, the rigidity of the molded article decreases,
If the content exceeds 10% by weight, the tensile resistance of the molded product deteriorates, which is not preferable.

The ethylene-propylene block copolymer of the present invention has heat resistance, rigidity, scratch resistance and the like when the content of the 20 ° C. xylene-soluble portion in the portion (I) exceeds 1.0% by weight. Not sufficient and not preferable. Ethylene of the present invention
When the propylene block copolymer is used in applications where heat resistance, rigidity, scratch resistance, etc. are particularly required, the isotactic pentad fraction calculated from ¹³ C-NMR of the portion (I) is It is preferably 0.975 or more.

The ethylene-propylene block copolymer of the present invention is particularly excellent in tensile properties and melt fluidity,
Used alone or as a compatibilizer for modifying the flowability of low MI polypropylene compositions.

The ethylene-propylene block copolymer of the present invention is an antioxidant, an ultraviolet absorber, a lubricant, an antistatic agent, a copper damage inhibitor, a flame retardant, a neutralizing agent, a nucleating agent, a foaming agent, a plasticizer. Additives such as pigments and dyes can be blended according to the purpose. Among these additives, it is desirable to add an antioxidant or an ultraviolet absorber in order to improve heat resistance, weather resistance and oxidation resistance stability.

Next, methods for measuring the above physical properties will be described. Isotactic pentad fraction means A. Z
Ambelli et al., Macromolecule
s, 6,925 (1973), that is, the isotactic chain in the pentad unit in the crystalline polypropylene molecular chain measured using 13 C-NMR, in other words, the propylene monomer unit It is the fraction of propylene monomer units at the center of a chain of five consecutive meso-bonds. However, regarding the assignment of NMR absorption peaks, Macromoleccu published afterwards was used.
les, 8, 687 (1975). Specifically, the isotactic pentad fraction is measured as the area fraction of the mmmm peak among all the absorption peaks in the methyl carbon region of the ¹³ C-NMR spectrum. By this method, NATIONAL PHYSICAL
LABORATORY NPL reference material CRMNo. M
19-14 Polypropylene PP / MW
It was 0.944 when the isotactic pentad fraction of D / 2 was measured.

Ethylene-based on the entire block copolymer
Weight ratio X of propylene random copolymer part (II)
Can be calculated from the following equation by measuring the heat of crystal fusion of each of the crystalline polypropylene portion and the entire block copolymer. X = 1− (ΔHf) _T / (ΔHf) _P (ΔHf) _T : heat of fusion (ca) of the entire block copolymer
1 / g) (ΔHf) _P : heat of fusion of the crystalline polypropylene part (cal / g)

The ethylene content of the ethylene-propylene random copolymer portion can be calculated by the following formula by measuring the ethylene content in the whole block copolymer by weight% by infrared absorption spectroscopy. (C ₂ ') _EP = (C ₂ ') _T / X (C ₂ ') _T : ethylene content (% by weight) of the entire block copolymer (C ₂ ') _EP : ethylene-propylene random copolymer part Ethylene content (wt%)

Further, the intrinsic viscosity [η] _EP of the ethylene-propylene random copolymer portion in a 135 ° C. tetralin solution is determined by measuring the intrinsic viscosity of each of the crystalline polypropylene portion and the block copolymer as a whole. It can be calculated from the formula. [Η] _EP = [η] _T / X- (1 / X-1) [η] _P [η] _P : intrinsic viscosity (dl) of the crystalline polypropylene part
/ G) [η] _T : intrinsic viscosity of the entire block copolymer (dl /
g)

[0028]

EXAMPLES The present invention will be described below with reference to examples, but these are merely examples, and the present invention is not limited to these examples unless departing from the gist. Next, methods for measuring physical properties in the examples are described below. (1) GPC measurement conditions The measurement was carried out by gel permeation chromatography (GPC) under the following conditions. The calibration curve was prepared using standard polystyrene. Model: 150CV type manufactured by Millipore Waters Co., Ltd. Column: Shodex M / S 80 Measurement temperature: 145 ° C, solvent ortho-dichlorobenzene Sample concentration: 5 mg / 8 ml Note that NBS (National Bureau of Standard) was used under these conditions.
s) Standard Reference Material 706 (Mw / M
When polystyrene (n = 2.1) was measured, a molecular weight distribution (Q value) Mw / Mn = 2.1 was obtained. (2) Melt flow index (MI) According to the method specified in JIS K 6758. The measurement temperature is 230 ° C. and the load is measured at 2.16 kg. (3) Bending test According to the method specified in JIS K 7106. 230
A test piece formed by press molding at ° C. is used. The thickness of the test piece is 4.0 mm, and the bending elastic modulus and the bending strength are evaluated under the conditions of a span length of 64 mm and a load speed of 2.0 mm / min. The measurement temperature is 23 ° C. (4) Tensile test According to the method specified in JIS K7113. 230
A test piece formed by press molding at ° C. is used. The thickness of the test piece is 1.0 mm, and the tensile elongation at break is evaluated. The measurement temperature is 23 ° C. (5) 20 ° C. xylene soluble part (CXS) After completely dissolving 5 g of polymer in 500 ml of boiling xylene, the temperature is lowered to 20 ° C. and the mixture is left standing for 4 hours. After that, this is separated by filtration to separate the xylene-soluble portion at 20 ° C. The filtrate is concentrated and evaporated to dryness to evaporate xylene.
To obtain a polymer soluble in xylene at 20 ° C.
Measure the weight. A value obtained by dividing this weight by the charged weight and expressing it as a percentage is defined as a 20 ° C. xylene-soluble portion (CXS) of the polymer.

(Production of Solid Catalyst) JP-A-1-31950
Synthesis was carried out as follows according to the method of Example 1 in JP-A-8. (1) Synthesis of solid product After replacing a 200 liter reaction vessel equipped with a stirrer and a dropping funnel with N ₂ , 80 liters of hexane and 2.23 liters of tetrabutoxytitanium (2.23 kg, 6.5).
5 mol), 0.75 liter (0.78 kg, 2.8 mol) of diisobutyl phthalate and 22.1 liters (20.6 kg, 98.9 mol) of tetraethoxysilane were added to form a homogeneous solution. Next, 51 l of an organomagnesium compound having a concentration of 2.1 mol / l was dropped dropwise over 5 hours while maintaining the temperature in the reaction vessel at 5 ° C. After completion of the dropwise addition, the mixture was further stirred at room temperature for 1 hour, and then separated into solid and liquid at room temperature.
After repeating the washing twice, toluene was added so that the slurry concentration became 0.2 kg / liter. A part of the solid product slurry was sampled and the composition was analyzed. In the solid product, 1.7% by weight of titanium atom, 0.1% by weight of phthalate ester and 32.7% by weight of ethoxy group were contained. %, Butoxy groups were contained in an amount of 3.5% by weight. (2) Synthesis of ester-treated solid After replacing a 200-liter reaction vessel with N ₂ , 13.26 kg (47.6 mol) of diisobutyl phthalate was added to the slurry containing the solid product obtained in (1) above. In addition,
The reaction was performed at 95 ° C. for 30 minutes. After the reaction, solid-liquid separation was performed, and washing was performed twice with 70 l of toluene. (3) Synthesis of solid catalyst component (activation treatment) After completion of the washing in the above (2), toluene and 0.87 kg (3.13 mol) of diisobutyl phthalate and 1.16 kg of butyl ether (8.16 kg) were placed in a reaction vessel. 9 mol) and 30 liters (274 mol) of titanium tetrachloride, and reacted at 105 ° C. for 3 hours. After the completion of the reaction, solid-liquid separation was carried out at the same temperature, followed by washing twice with 90 liters of toluene at the same temperature. Then, 1.16 kg of toluene and butyl ether
(8.9 mol), and 15 liters of titanium tetrachloride (1
37 mol), and reacted at 105 ° C. for 1 hour. After completion of the reaction, the mixture was separated into solid and liquid at the same temperature, washed three times with 90 l of toluene at the same temperature, washed three times with 70 l of hexane, and dried under reduced pressure to obtain 11.4 kg of a solid catalyst component. Was.

Example 1 An agitated stainless steel autoclave having an internal volume of 3 liters was purged with nitrogen and charged with 1.0 liter of n-heptane obtained by purification by treatment with active Al ₂ O ₃ under reduced pressure. Then 8.8 mmol of triethylaluminum,
And cyclohexylethyldimethoxysilane 1.8m
mol, 89.8 mg of the above solid catalyst were charged at the same time,
33 vol% of hydrogen was added to the total pressure. Then 50g
Was charged with propylene gas and the autoclave temperature was increased to 7
Propylene gas was fed while the temperature was raised to 5 ° C, and the polymerization was continued at 75 ° C for 1 hour at a polymerization pressure of about 6.0 kg / cm ² G. After the polymerization was completed, unreacted monomers were purged, and a small amount of the polymer powder was sampled in an Ar atmosphere while lowering the temperature.
This sample is used to measure the intrinsic viscosity of the P part, CXS, etc. Then, pressurized flow was continued for 1 hour so that a mixed gas of 7.07 vol% propylene gas, 24.0 vol% ethylene gas and 4.9 vol% hydrogen gas was kept at about 3.0 kg / cm ² G at 60 ° C. After completion of the polymerization, the unreacted monomer was purged, and iso-butanol as a polymerization terminator was added to about 2
0 ml was added, the mixture was stirred for 15 minutes at the same temperature, and then 3.0 ml of propylene oxide was added to decalcify. The contents of the autoclave were put into about 4 times the amount of ethanol, filtered with a rag cloth, and dried under reduced pressure at 60 ° C. for 4 hours to obtain 252 g of an ethylene-propylene block copolymer. Therefore, ethylene per gram of solid catalyst
Yield (g) of propylene block copolymer (hereinafter PP /
(abbreviated as cat) was PP / cat = 2810.
100 parts by weight of the obtained copolymer was mixed with Sumilizer BHT (trade name, manufactured by Sumitomo Chemical Co., Ltd., 2,6-di-tert).
-Butyl 4-methylphenol) 0.1 part by weight, trade name Irganox 1010 (manufactured by Ciba Geigy, pentaerystyl-tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate])
The copolymer obtained by adding 0.05 part by weight and 0.15 part by weight of calcium stearate and mixing for 10 minutes with a small heat roll kneader at 190 ° C. was chopped into pellets, followed by press molding. The physical properties were measured. The ethylene content (% by weight) was 7.4% by weight by the IR spectrum method, and the heat of fusion measured by a differential scanning calorimeter was 26.53 cal / g in the former homopolymer and 17 in the ethylene-propylene block copolymer. It was 0.0 cal / g. From each ratio, the ethylene-propylene random copolymer part (EP part) was 36% by weight of the total polymer, and the ethylene content in the ethylene-propylene random copolymer was 21% by weight. On the other hand, the intrinsic viscosity measured in 135 ° C. tetralin was 0.62 dl for the homopolymer (P part) in the previous stage.
/ G, the whole polymer was 1.04 dl / g, and the ethylene-propylene random copolymer part was 1.8 dl / g from each ratio.

Comparative Example 1 1.0 liter of n-heptane obtained by purifying a stirred stainless steel autoclave with an internal volume of 3 liters by purging with nitrogen and treatment with active Al ₂ O ₃ under reduced pressure was added. Then 8.8 mmol of triethylaluminum,
And cyclohexylethyldimethoxysilane 1.8m
mol, 30.3 mg of the above solid catalyst were charged at the same time,
Hydrogen was added in an amount of 4.0 vol% with respect to the total pressure. Then 50
g of propylene gas was charged, propylene gas was fed while raising the temperature of the autoclave to 75 ° C., and the polymerization was continued at 75 ° C. for 1 hour at a polymerization pressure of 6.0 kg / cm ² G. After the polymerization was completed, unreacted monomers were purged, and a small amount of the polymer powder was sampled in an Ar atmosphere while lowering the temperature. Then, 61.7 vol% propylene gas and 3 ethylene gas were added.
About 8.3vol% mixed gas at 40 ℃ about 3.0kg / c
Flowing under pressure was continued for 1.2 hours so as to maintain m ² G. After the polymerization is completed, the unreacted monomer is purged to
About 20 ml of o-butanol was added, the mixture was stirred at the same temperature for 15 minutes, and then 3.0 ml of propylene oxide was added to decalcify. About 4 contents of autoclave
After pouring it in twice the amount of ethanol, filter it with a rag cloth,
It was dried under reduced pressure at 60 ° C. for 4 hours to obtain 177 g of an ethylene-propylene block copolymer. Therefore, 1 g of solid catalyst
The yield (g) of ethylene-propylene block copolymer per unit (hereinafter abbreviated as PP / cat) is PP / cat =
It was 5890. 100 parts by weight of the obtained copolymer,
Product name Sumilizer BHT (Sumitomo Chemical Co., Ltd.,
2,6-di-tert-butyl 4-methylphenol)
0.1 parts by weight, trade name Irganox 1010 (manufactured by Ciba-Geigy, pentaerystil-tetrakis [3- (3,
5-di-tert-butyl-4-hydroxyphenyl)
Propionate]) 0.05 part by weight and 0.15 part by weight of calcium stearate were added and mixed for 10 minutes with a small heat roll kneader at 190 ° C. The resulting copolymer was shredded into pellets and then pressed. After molding, each physical property was measured. Its ethylene content (% by weight) is 1 by IR spectroscopy.
1.8% by weight, the heat of fusion measured by a differential scanning calorimeter was 25.48 cal / g in the former homopolymer and 18.02 cal in the ethylene-propylene block copolymer.
/ G. From the respective proportions, the ethylene-propylene random copolymer portion was 29% by weight of the total polymer, and the ethylene content in the ethylene-propylene random copolymer was 40% by weight. On the other hand, the intrinsic viscosity measured in 135 ° C tetralin was 1.22 for the homopolymer in the previous stage.
dl / g, the whole polymer was 3.27 dl / g, and the ethylene-propylene random copolymer part was 8.2 dl / g from each ratio.

Table 1 shows the evaluation results of Example 1 and Comparative Example 1. Example 1 exhibits rigidity equivalent to that of Comparative Example 1, and is excellent in melt flow index (MI) and tensile elongation at break.

Example 2 The solid catalyst was 41.5 mg, and the hydrogen was 1 to the total pressure.
8.0 vol% was added and the mixed gas composition was changed to propylene gas 5
Polymerization was carried out in the same manner as in Example 1 except that 4.0 vol% and 46.0 vol% of ethylene gas were used, and the obtained ethylene-propylene block copolymer was 153 g, and PP / cat
= 3700. The ethylene content of the obtained copolymer was 7.5% by weight, and from the ratio of heat of fusion, the ethylene-propylene random copolymer portion was 17% by weight of the total polymer,
The ethylene content in the ethylene-propylene random copolymer was 44% by weight. On the other hand, the intrinsic viscosity was 0.80 dl / g in the former homopolymer part and 1.45 dl / g in the whole polymer, and the ethylene-propylene random copolymer part was 4.6 dl / g from the respective ratios. . .

Comparative Example 2 The solid catalyst was 46.3 mg, and hydrogen was added to the total pressure of 7.
0 vol% was added and the mixed gas composition was changed to propylene gas 33.
Polymerization was carried out in the same manner as in Example 1 except that 0 vol% and 67.0 vol% ethylene gas were used, and the obtained ethylene-propylene block copolymer was 182 g and PP / cat = 3.
It was 740. The ethylene content of the obtained copolymer was 8.5% by weight, and from the ratio of the heat of fusion, the ethylene-propylene random copolymer part was 14% by weight of the whole polymer, and the ethylene content in the ethylene-propylene random copolymer was The amount was 61% by weight. On the other hand, the intrinsic viscosity was 1.09 dl / g in the homopolymer part in the former stage and 1.5 in the whole polymer.
It was 8 dl / g, and from each ratio, the ethylene-propylene random copolymer part was 4.6 dl / g.

Table 1 shows the evaluation results of Example 2 and Comparative Example 2. Example 2 exhibits the same rigidity and tensile elongation at break as Comparative Example 2, and is excellent in the melt flow index (MI).

Example 3 The solid catalyst was 92.9 mg, and the mixed gas composition was 85.2 vol% propylene gas and 14.8 vol ethylene gas.
Polymerization was carried out in the same manner as in Example 1 except that the content of ethylene-propylene block copolymer was 245 g.
/ Cat = 2630. The ethylene content of the obtained copolymer was 2.1% by weight, and from the ratio of the heat of fusion, the ethylene-propylene random copolymer portion contained 9% by weight of the total polymer, and the ethylene content of the ethylene-propylene random copolymer was The amount was 23% by weight. On the other hand, the intrinsic viscosity is
The homopolymer part in the former stage was 0.60 dl / g, the whole polymer was 1.06 dl / g, and the ethylene-propylene random copolymer part was 5.7 dl / g from each ratio.
g.

Comparative Example 3 The solid catalyst was 102.5 mg, and the mixed gas composition was propylene gas 279.9 vol% and ethylene gas 14.6 v.
Example 1 except that the ol% and the hydrogen gas were 5.5 vol%
Polymerization was carried out in the same manner as above to obtain 230 g of an ethylene-propylene block copolymer, and PP / cat = 2250. The ethylene content of the obtained copolymer was 3.4% by weight, and from the ratio of heat of fusion, the ethylene-propylene random copolymer portion was 26% by weight of the total polymer, and the ethylene content in the ethylene-propylene random copolymer was The amount was 13% by weight. On the other hand, the intrinsic viscosity was 0.60 dl / g in the homopolymer part in the previous stage and 0.87 dl / g in the whole polymer.
From each ratio, the ethylene-propylene random copolymer portion was 1.6 dl / g.

Table 1 shows the evaluation results of Example 3 and Comparative Example 3. Example 3 has the same MI and tensile elongation at break as Comparative Example 3, and is excellent in rigidity.

Example 4 The solid catalyst was 57.2 mg, and the mixed gas composition was propylene gas 83.7 vol% and ethylene gas 16.3 vol.
Polymerization was carried out in the same manner as in Example 1 except that the content was 138 g, and the obtained ethylene-propylene block copolymer was 138 g.
/ Cat = 2410. The ethylene content of the obtained copolymer was 1.0% by weight, and the ethylene-propylene random copolymer portion contained 2% by weight of the total polymer based on the ratio of heat of fusion, and the ethylene content of the ethylene-propylene random copolymer was The amount was 50% by weight. On the other hand, the intrinsic viscosity is
The homopolymer part in the former stage was 0.60 dl / g, the whole polymer was 0.74 dl / g, and the ethylene-propylene random copolymer part was 7.6 dl / g from the respective ratios.
g.

Comparative Example 4 The solid catalyst was 108.7 mg, and the mixed gas composition was propylene gas 61.7 vol% and ethylene gas 38.3 vo.
Polymerization was carried out in the same manner as in Example 1 except that the pressure was set to 1% and the flow under pressure was continued at 40 ° C. for 27 minutes. The ethylene-propylene block copolymer obtained was 156 g, and PP / cat
= 1430. The ethylene content of the obtained copolymer was 5.8% by weight, and from the ratio of the heat of fusion, the ethylene-propylene random copolymer portion contained 9% by weight of the whole polymer, and the ethylene content in the ethylene-propylene random copolymer was The amount was 64% by weight. On the other hand, the intrinsic viscosity was 0.58 dl / g in the former homopolymer part and 1.
It was 49 dl / g, and the ethylene-propylene random copolymer part was 10.8 dl / g from each ratio.

Table 1 shows the evaluation results of Example 4 and Comparative Example 4. Example 4 shows a tensile elongation at break equivalent to that of Comparative Example 4,
It is also excellent in terms of rigidity and MI.

[0042]

[Table 1]

Claims (1)

[Claims] 1. A propylene homopolymer or a crystalline polypropylene portion obtained by copolymerizing propylene with ethylene or an α-olefin having 4 or more carbon atoms in an amount of 1 mol% or less, and the composition ratio of ethylene and propylene is ethylene / propylene = weight ratio. It has an ethylene-propylene random copolymer portion of 10/90 to 50/50, and (1) the intrinsic viscosity [η] _P of a 135 ° C. tetralin solution of the crystalline polypropylene portion is 0.5 to 0.8 dl / g. , Q value which is a weight average molecular weight (Mw) / number average molecular weight (Mn) ratio by gel permeation chromatography (GPC) method is 5
Hereinafter, 1.0% by weight or less of the 20 ° C. xylene-soluble portion,
(2) 1 of ethylene-propylene random copolymer part
Intrinsic viscosity [η] _{EP of} 35 ° C tetralin solution is 1.5-
8.0 dl / g, (3) ethylene-propylene random copolymer portion is 1 to 40 wt% of the total polymer, and (4) melt flow index (MI) is 7
An ethylene-propylene block copolymer which is 0 to 1000 g / 10 minutes.