JPH059219A - Polypropylene resin and its composition - Google Patents

Abstract

PURPOSE:To provide a polyprophlene resin having very high rigidity, heat resistance and impact resistance and an excellent balance among them, and its composition. CONSTITUTION:A polypropylene resin which comprises a propylene copolymer having a content of alpha-olefin units other than propylene units of 4mol% or below, an mmmm fraction of 96.0% or above in a pentad fraction as determined by 13C NMR, a main elution peak in climbing temperature fractionation positioned at 118 deg.C or above (Tmax), a half-width (sigma) of below 3.4 deg. and an intrinsic viscosity [eta]of 0.5-2.0dl/g, and containing a propylene copolymer having an intrinsic viscosity [eta] of 3.0dl/g or above.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a polypropylene resin having extremely high rigidity, heat resistance and impact resistance, and a composition thereof.

[0002]

PRIOR ART AND PROBLEM TO BE SOLVED BY THE INVENTION In the first step, a propylene homopolymer or copolymer is produced,
The composition obtained by randomly copolymerizing propylene and another α-olefin in the second stage is generally referred to as a propylene block copolymer. Such a block copolymer has a significantly improved low temperature impact strength without significantly impairing the excellent rigidity and heat resistance of polypropylene. Conventionally, the production of a propylene block copolymer, generally, using a high stereoregular catalyst, after producing a homopolymer or copolymer of propylene in the polymerization stage of the previous stage in the homopolymerization tank, the latter stage in the random copolymerization tank In the polymerization step (1), propylene and another α-olefin are randomly copolymerized in the presence of the above-mentioned polymer or copolymer.

As described above, a means for improving impact resistance by sequentially carrying out propylene / olefin copolymerization in the presence of a highly stereoregular catalyst has been taken. Therefore, the balance between rigidity and impact resistance could not be removed from the insufficient region.

The present invention has been made in view of the above circumstances.
An object of the present invention is to provide a polypropylene resin having extremely high rigidity, heat resistance and impact resistance, and a composition thereof.

[0005]

Means and Actions for Solving the Problems The present inventors have
It has been found that polypropylene having a specific resin structure remarkably improves the rigidity and heat resistance of the resin. As a result of carrying out the present invention, it was found that the polypropylene block copolymer is excellent in the balance between rigidity and impact strength while maintaining the rigidity and heat resistance of the polypropylene having the specific resin structure. I arrived.

Therefore, according to the present invention, the content of α-olefin units other than propylene is 4 m.
ol% or less, the following characteristics, and the pentad fraction measured by ¹³ C-NMR is mm
The mm fraction is 96.0% or more, and the position (Tmax) of the main elution peak in the temperature rising fractionation method is 1
At a temperature of 18.0 ° C. or higher and a peak half width (σ) of less than 3.4 degrees, an intrinsic viscosity [η] is 0.5 dl / g or more, 2.0 dl /
Provided is a polypropylene-based resin, which contains a propylene copolymer having a g or less and has an intrinsic viscosity [η] of 3.0 dl / g or more. Further, the present invention may be a polypropylene resin composition containing at least the above polypropylene resin and optionally other resins such as EPR, EPDM and polyethylene.

The present invention will be described in more detail below.
First, each characteristic will be described in detail. Content of α-olefin unit other than propylene The polypropylene-based resin of the present invention contains α-olefin units other than propylene.
-Olefin, ie ethylene and / or carbon number 4
The content of the above α-olefin unit is 4 mol% or less,
Preferably, it is 0 to 2.0 mol%. If the content of α-olefin units other than propylene exceeds 4 mol%, the rigidity and heat resistance are insufficient.

The polypropylene resin of the present invention contains a propylene copolymer having the following characteristics and. Pentad Fraction (mmmm Fraction) The mmmm fraction referred to in the present invention is a value obtained by measurement by ¹³ C-NMR. The propylene copolymer contained in the polypropylene resin of the present invention has ¹³ C-NMR.
The pentad fraction measured in 1. is 96.0% or more, preferably 97.0% or more, more preferably 97.5% or more. If the value of the pentad fraction is less than 96.0%, the rigidity and heat resistance are insufficient. Main elution peak position and half-value width of the peak by the temperature rising fractionation method, these values are introduced into the column, after adsorbing the sample to the packing material, the column temperature is raised,
It can be measured by detecting the concentration of polymer eluted at each temperature. Here, the main elution peak position (Tm
The ax) and the peak half width (σ) are values defined by the analysis chart shown in FIG. 1. That is, Tmax
Is the peak position (temperature) when the largest peak appears, and σ is the peak width at a position half the height of the peak. Since the stereoregularity of the polymer depends on the elution temperature, the stereoregularity distribution of the polymer can be known by determining the relationship between the elution temperature and the polymer concentration by the temperature rising fractionation method.

The propylene copolymer contained in the polypropylene resin of the present invention has a main elution peak (Tmax) measured by the temperature rising fractionation method of 118.0 ° C. or higher, preferably 11
The temperature is 8.5 ° C or higher, and more preferably 119.0 ° C or higher. Further, the full width at half maximum (σ) of the main elution peak is less than 3.4 degrees, preferably less than 3.2 degrees, and more preferably 3.
It is less than 0 degrees. The position of the main elution peak (Tmax) is 1
If the temperature is lower than 18.0 ° C, not only the rigidity and heat resistance are lowered, but also the effect of limiting the intrinsic viscosity to a predetermined value is not exhibited. Further, when the half-value width (σ) of the main elution peak is 3.4 degrees or more, not only the rigidity and heat resistance are insufficient, but also the effect of limiting the intrinsic viscosity to a predetermined value is not exhibited.

Intrinsic viscosity [η] The intrinsic viscosity [η] in the present invention is a value measured in decalin at 135 ° C. The propylene copolymer contained in the polypropylene resin of the present invention has an intrinsic viscosity of 0.5 to
2.0 dl / g, preferably 0.7-1.5 dl /
g, and more preferably 0.8 to 1.2 dl / g.
If the intrinsic viscosity is less than 0.5 dl / g, the impact strength will be insufficient, and if it exceeds 2.0 dl / g, the rigidity-impact strength balance will be similar to that of the prior art.

The polypropylene resin of the present invention contains, in addition to the propylene copolymer having the above characteristics and properties, other propylene copolymers having the following intrinsic viscosity. Here, the intrinsic viscosity [η] is a value measured in decalin at 135 ° C. as described above. The intrinsic viscosity of the other propylene copolymer is 3.0 dl / g or more, preferably,
3.5 dl / g or more, more preferably 4.0 dl / g
That is all. If the intrinsic viscosity is less than 3.0 dl / g, the impact strength will be insufficient.

The method for producing the polypropylene resin of the present invention having the above characteristics is not particularly limited, but it is preferable to use a polymerization catalyst capable of exhibiting high polymerization activity and stereoregularity. Examples of such a polymerization catalyst and a method for producing a polyolefin using the polymerization catalyst include a polymerization catalyst and a production method disclosed in Japanese Patent Application No. 2-413883 previously filed by the present applicant. . Japanese Patent Application 2-4138
The polymerization catalyst disclosed in No. 83 is characterized by using a solid product (a) obtained by reacting metallic magnesium, an alcohol and a specific amount of halogen as a carrier. Then, a solid catalyst component (A) obtained by using such a solid product (a), a titanium compound (b), and optionally an electron donating compound (c), an organometallic compound (B), and optionally Polymerization is carried out using an electron donating compound (C).

The solid product (a) is obtained from magnesium metal, alcohol, halogen and / or halogen-containing compound. In this case, the shape of metallic magnesium is not particularly limited. Therefore, it is possible to use metallic magnesium having an arbitrary particle diameter, for example, granular, ribbon-shaped or powdered metallic magnesium. The surface state of the metallic magnesium is not particularly limited, but it is preferable that the surface of the metallic magnesium is not coated with magnesium oxide.

Although any alcohol can be used, it is preferable to use a lower alcohol having 1 to 6 carbon atoms. In particular, the use of ethanol is preferable because a solid product that significantly improves the expression of catalytic performance can be obtained. The purity and the water content of the alcohol are not limited, but when an alcohol having a high water content is used, magnesium hydroxide [Mg (OH) ₂ ] is produced on the surface of magnesium metal, so that the water content is 1% or less, particularly 2000 ppm.
It is preferable to use the following alcohols. Furthermore, in order to obtain a solid product (a) having a better morphology, the smaller the water content, the more preferable, and generally 200 ppm or less is desirable.

The type of halogen is not particularly limited, but chlorine, bromine or iodine, especially iodine is preferably used. The kind of the halogen-containing compound is not limited, and any compound containing a halogen atom in its chemical formula can be used. In this case, the type of halogen atom is not particularly limited, but chlorine, bromine or iodine is preferable. Further, among the halogen-containing compounds, halogen-containing metal compounds are particularly preferable. As the halogen-containing compound, specifically, MgCl ₂ , MgI ₂ , M
g (OEt) Cl, Mg (OEt) I, MgBr ₂ , C
ACl ₂ , NaCl, KBr, etc. can be preferably used. Of these, MgCl ₂ and MgI ₂ are particularly preferable. These states, shapes, particle sizes and the like are not particularly limited and may be arbitrary, and for example, they can be used in the form of a solution in an alcohol solvent (for example, ethanol).

The amount of alcohol is not limited, but it is preferably 2 to 100 mol, and particularly preferably 5 to 50 mol per 1 mol of metal magnesium. If the amount of alcohol is too large, the yield of the solid product (a) having a good morphology may decrease, and if it is too small, stirring in the reaction tank may not be smoothly performed. However, the molar ratio is not limited.

The amount of halogen used is metallic magnesium 1
The amount of gram atom is 0.0001 gram atom or more, preferably 0.0005 gram atom or more, and more preferably 0.001 gram atom or more. The halogen-containing compound has a halogen atom in the halogen-containing compound of 0.0001 gram atom or more, preferably 0.0005 gram atom or more, based on 1 gram atom of metallic magnesium.
More preferably, it is used in an amount of 0.001 gram atom or more. If the amount is less than 0.0001 gram atom, there is no great difference from the amount of halogen used as the reaction initiator, and the pulverizing and classifying treatment of the solid product is indispensable to obtain the desired particle size.

Each of the halogen and the halogen-containing compound may be used alone or in combination of two or more. Further, halogen and a halogen-containing compound may be used in combination. When halogen and a halogen-containing compound are used in combination, the total amount of halogen atoms is 0.0001 gram atom or more per 1 gram atom of metallic magnesium.
The amount is preferably 0.0005 gram atom or more, and more preferably 0.001 gram atom or more. The upper limit of the amount of halogen and / or halogen-containing compound used is not particularly limited and may be appropriately selected within a range in which the desired solid product is obtained. Generally, the amount of all halogen atoms is 1 g of magnesium metal. It is preferably less than 0.06 gram atom per atom. In this case, halogen and /
Alternatively, the particle size of the solid product can be freely controlled by appropriately selecting the amount of the halogen-containing compound used.

The reaction itself of the magnesium metal, the alcohol, the halogen and / or the halogen-containing compound can be carried out in the same manner as a known method. For example, metallic magnesium, an alcohol, a halogen and / or a halogen-containing compound are reacted under reflux (about 79 ° C.) until generation of hydrogen gas is no longer recognized (usually about 20 to 30 hours) to produce a solid. It is a way to get things. Specifically, for example, when iodine is used as the halogen, a method in which solid iodine is introduced into metallic magnesium and alcohol, and then heated and refluxed, metallic alcohol is added after the alcohol solution of iodine is dropped into the alcohol and heated. And the like, and a method of dropping an alcohol solution of iodine while heating the magnesium metal or alcohol solution. Both methods are preferably carried out under an inert gas (for example, nitrogen gas or argon gas) atmosphere, optionally using an inert organic solvent (for example, saturated hydrocarbon such as n-hexane).

Regarding the addition of magnesium metal, alcohol, halogen and / or halogen-containing compound, it is not necessary to add the whole amount to the reaction tank from the beginning, and it may be added in a divided manner. A particularly preferable form is a method in which the entire amount of alcohol is charged from the beginning, and metallic magnesium is charged in several times. If you do this,
It is possible to prevent the generation of a large amount of hydrogen gas temporarily, which is highly desirable from the viewpoint of safety. Also, the reaction tank can be downsized. Further, it becomes possible to prevent the entrainment of alcohol, halogen and / or halogen-containing compound caused by the temporary large generation of hydrogen gas. The number of divisions may be determined in consideration of the scale of the reaction tank,
Although not particularly limited, it is usually 5 to 10 in consideration of complexity of operation.
Times are preferred.

It goes without saying that the reaction itself may be either batch type or continuous type. Furthermore, as a modified method, a small amount of metallic magnesium is first added to the alcohol that has been entirely added from the beginning, the product produced by the reaction is separated and removed in another tank, and then a small amount of metallic magnesium is added again. It is also possible to repeat. When the solid product (a) thus obtained is used for the next synthesis of the solid catalyst component, a dried product may be used, or a product washed with an inert solvent such as heptane after filtration may be used. Good. In any case, the obtained solid product (a) can be used in the following steps without pulverization or classification operation for adjusting the particle size distribution.

Further, the solid product (a) is close to spherical and has a sharp particle size distribution. Furthermore, even if each particle is taken, the variation in sphericity is very small.
In this case, the sphericity (S) represented by the following formula (1) is less than 1.60, particularly less than 1.40, and the particle size distribution index (P) represented by the following formula (2) is 5.0. It is preferably less than 4.0, particularly less than 4.0. S = (E1 / E2) ² (1) (where E1 is the contour length of the projected particle and E2 is the circumference of a circle equal to the projected area of the particle.) P = D90 / D10 ... (2) (Here, D90 means a particle size corresponding to a weight cumulative fraction of 90%. That is, the weight sum of the particle groups smaller than the particle size represented by D90 is 90% of the total weight of all particles. (The same applies to D10.)

Examples of the titanium compound (b) in the above solid catalyst component (A) include, for example, the general formula TiX ¹ n (OR ¹ ) _4-n (wherein X ¹ is a halogen atom, especially a chlorine atom, and R ¹
Is a hydrocarbon group having 1 to 10 carbon atoms, in particular a linear or branched alkyl group, and when a plurality of groups R ¹ are present, they may be the same or different from each other. n is 0-4
Is an integer. ) And titanium compounds. Specifically, Ti (O-i-C 3 H 7) 4, Ti (O
_{-C 4 H 9) 4, TiCl} (O-C 2 H 5) 3, TiCl (O
_{-I-C 3 H 7) 3} , TiCl (O-C 4 H 9) 3, TiCl
_{2 (O-C 4 H 9} ) 2, TiCl 2 (O-i-C 3 H 7) 2, T
Examples thereof include iCl ₄ .

In the above solid catalyst component (A), any electron donating compound (c) can be used if necessary. The electron donating compound (c) is usually an organic compound containing oxygen, nitrogen, phosphorus or sulfur. Specifically, amines, amides, ketones, nitriles, phosphines, phosmylamides, esters, ethers, thioethers, alcohols, thioesters, acid anhydrides, acid halides, aldehydes, Examples thereof include organic acids and organic silicon compounds having a Si—O—C bond, and more specific examples include the following.

Aromatic carboxylic acids such as benzoic acid, p
-Oxybenzoic acid; acid anhydrides such as succinic anhydride,
Benzoic anhydride, p-toluic anhydride; C3 to C1
5 ketones, such as acetone, methyl ethyl ketone, methyl isobutyl ketone, acetophenone, benzophenone, benzoquinone; aldehydes having 2 to 15 carbon atoms, such as acetaldehyde, propionaldehyde, octylaldehyde, benzalded, naphthaldehyde; 2 carbon atoms ~ 18 esters, for example:
Methyl formate, ethyl formate, methyl acetate, ethyl acetate, vinyl acetate, propyl acetate, octyl acetate, cyclohexyl acetate, ethyl propionate, methyl butyrate, ethyl butyrate, ethyl valerate, methyl chloroacetate, ethyl dichloroacetate, methyl methacrylate, Ethyl crotonate, ethyl pivalate, dimethyl maleate, ethyl cyclohexanecarboxylate, methyl benzoate, ethyl benzoate, propyl benzoate, butyl benzoate, octyl benzoate, cyclohexyl benzoate, phenyl benzoate, benzyl benzoate, toluyl. Methyl acid, ethyl toluate, amyl toluate, ethyl ethyl benzoate, methyl anisate,
Ethyl anisate, ethyl ethoxybenzoate, ethyl p-butoxybenzoate, ethyl o-chlorobenzoate, ethyl naphthoate, γ-butyrolactone, δ-valerolactone, coumarin, phthalide, ethylene carbonate;

Aromatic dicarboxylic acid mono and diesters such as phthalic acid monoesters and diesters are preferred, for example monomethyl phthalate, dimethyl phthalate, monomethyl terephthalate, dimethyl terephthalate, monoethyl phthalate, diethyl phthalate,
Monoethyl terephthalate, diethyl terephthalate,
Monopropyl phthalate, dipropyl phthalate, monopropyl terephthalate, dipropyl terephthalate,
Monobutyl phthalate, dibutyl phthalate, monobutyl terephthalate, dibutyl terephthalate, monoisobutyl phthalate, diisobutyl phthalate, monoamyl phthalate, diamyl phthalate, monoisoamyl phthalate, diisoamyl phthalate, ethyl butyl phthalate, ethyl isobutyl phthalate, ethyl propyl phthalate;

Acid halides having 2 to 20 carbon atoms,
The acid portion (acyl group portion) of the acid halide is an aliphatic (including those having a ring such as alicyclic) carbon atoms of about 2 to 20, monobasic, dibasic or tribasic. A monovalent to trivalent acyl acid obtained by removing each hydroxyl group from an acid, or an aromatic (alkali-containing) having about 7 to 20 carbon atoms.
Also includes le-type and aralkyl-type. ) Monovalent to trivalent acyl groups obtained by removing each hydroxyl group from a monobasic, dibasic or tribasic acid of the system are preferred. The halogen atom in the acid halide is preferably a chlorine atom, a bromine atom, etc., and particularly preferably a chlorine atom.

Acid halides that can be preferably used include, for example, acetyl chloride, acetyl bromide, propionyl chloride, butyryl chloride, isobutyryl chloride, 2-methylpropionyl chloride,
Valeryl chloride, isovaleryl chloride, hexanoyl chloride, methylhexanoyl chloride, 2-ethylhexanoyl chloride, octanoyl chloride, decanoyl chloride, undecanoyl chloride, hexadecanoyl chloride, octadecanoyl chloride, benzylcarbonyl Chloride, cyclohexane carbonyl chloride, malonyl dichloride, succinyl dichloride, pentane dioil dichloride, hexane dioil dichloride, cyclohexane dicarbonyl dichloride, benzoyl chloride, benzoyl bromide, methylbenzoyl chloride, phthaloyl chloride, isophthaloyl chloride, terephthaloyl chloride. , Benzene-1,2,4-
Tricarbonyl trichloride etc. can be mentioned. Among these, phthaloyl chloride, isophthaloyl chloride, terephthaloyl chloride and the like are preferable, and phthaloyl chloride is particularly preferable. These acid halides may be used alone or in combination of two or more.

Ethers having 2 to 20 carbon atoms such as methyl ether, ethyl ether, isopropyl ether, n-butyl ether, amyl ether, tetrahydrofuran, anisole, diphenyl ether, ethylene glycol butyl ether; acid amides such as acetic acid amide, benzoic acid Acid amide, toluic acid amide; amines such as tributylamine, N, N′-dimethylpiperazine, tribenzylamine, aniline, pyridine,
Pyroline, tetramethylethylenediamine; Nitriles such as acetonitrile, benzonitrile, tolunitrile; Tetramethylurea, nitrobenzene, lithium butyrate;

Organosilicon compounds having a Si--O--C bond, such as trimethylmethoxysilane, trimethylethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, diphenyldimethoxysilane, methylphenyldimethoxysilane, diphenyldiethoxysilane, phenyltri. Methoxysilane, γ-chloropropyltrimethoxysilane, methyltriethoxysilane, ethyltriethoxysilane, vinyltriethoxysilane, butyltriethoxysilane, phenyltriethoxysilane, γ-aminopropyltriethoxysilane, chlorotriethoxysilane, ethyl Triisopropoxysilane,
Vinyltributoxysilane, isopropylcyclohexyldimethoxysilane, isobutylcyclohexyldimethoxysilane, tert-butylcyclohexyldimethoxysilane, isopropylcyclohexyldiethoxysilane,
Isobutylcyclohexyldiethoxysilane, tert-butylcyclohexyldiethoxysilane, methylcyclohexyldimethoxysilane, ethyl silicate, butyl silicate, trimethylphenoxysilane, methyltriaryloxysilane, vinyltris (β-methoxyethoxy) silane, vinyltriacetoxysilane , Dimethyltetraethoxydisiloxane, and the like. Among these, preferred are esters, ethers, ketones, acid anhydrides and the like.

The solid catalyst component (A) can be prepared by a known method using (a) a solid product, (b) a titanium compound and, if necessary, (c) an electron donating compound. . For example, it is preferable to contact the solid product (a) with the electron-donating compound (c) and then contact with the titanium compound (b). The conditions for bringing the electron donating compound (c) into contact with the solid product (a) are not particularly limited and may be appropriately determined depending on various circumstances. Usually, 0.01 to 10 moles of the electron-donating compound (c), preferably 0.1 to 1 mole of the solid product (a) in terms of magnesium atom.
05 to 5 moles may be added, and the catalytic reaction may be performed at 0 to 200 ° C. for 5 minutes to 10 hours, preferably at 30 to 150 ° C. for 30 minutes to 3 hours. Incidentally, an inert hydrocarbon such as pentane, hexane, heptane or octane can be added to this reaction system as a solvent.

The titanium compound (b) is added to the solid product (a) or the contact product of the solid product (a) and the electron-donating compound (c).
There are no particular restrictions on the conditions for contacting, but usually 1 to 50 mol, preferably 2 to 20 mol of the titanium compound (b) is added to 1 mol of magnesium in the product. The reaction is performed at ˜200 ° C. for 5 minutes to 10 hours, preferably at 30 to 150 ° C. for 30 minutes to 5 hours. The liquid titanium compound (for example, titanium tetrachloride) is used alone for the contact with the titanium compound (b), and the titanium compound other than the above is used for any inert hydrocarbon solvent (for example, hexane,
It can be carried out in a state of being dissolved in heptane, kerosene). In addition, prior to the contact between the solid product (a) and the titanium compound (b), and optionally the electron-donating compound (c), for example, a halogenated hydrocarbon, a halogen-containing silicon compound, It is also possible to bring halogen gas, hydrogen chloride, hydrogen iodide, or the like into contact with the solid product (a).
After the reaction, it is preferable to wash the product with an inert hydrocarbon (for example, n-hexane or n-heptane).

As the organic metal compound (B), any organic compound containing a metal of Groups 1 to 3 of the periodic table can be preferably used. Examples of the metals of Groups 1 to 3 of the periodic table include lithium, sodium, potassium, zinc, cadmium, aluminum and the like, and aluminum is particularly preferable. Specific examples of the organometallic compound (B) include alkyllithium, for example,
Methyl lithium, ethyl lithium, propyl lithium or butyl lithium; dialkyl zincs such as dimethyl zinc, diethyl zinc, dipropyl zinc or dibutyl zinc.

As the organoaluminum compound,
In the general formula ^{_{AlR 2 m X 2 3-m}} ( wherein, R ² is an alkyl group, a cycloalkyl group or an aryl group having 1 to 10 carbon atoms, m is an integer of 1 to 3, X ² is a halogen Compounds represented by atoms such as chlorine or bromine are widely used. Specifically, trialkyl aluminum compounds such as trimethyl aluminum, triethyl aluminum, triisopropyl aluminum, triisobutyl aluminum or trioctyl aluminum; or dialkyl aluminum monohalide compounds such as diethyl aluminum monochloride and dipropyl aluminum monochloride. Alternatively, dioctylaluminum monochloride and the like can be mentioned.

The electron donating compound (C) can be used in combination, if necessary. In this case, as the electron donating compound (C), the same one as the electron donating compound (c) used in the preparation of the solid catalyst component (A) can be used. At this time, the electron donating compound (C) is
It may be the same as or different from the electron-donating compound (c) used in the preparation of the solid catalyst component (A).

The production method (polymerization conditions) of the polypropylene resin of the present invention is not particularly limited. Alternatively, after the copolymer is produced, it can be produced by random copolymerization of propylene and other α-olefin in the presence of the above-mentioned polymer or the copolymer in the subsequent polymerization stage in a random copolymerization tank (Japanese Patent Application No. Hei 10 (1999) -135242) See 3-106318).

In this case, the crystalline polymer or copolymer of propylene is produced in the previous stage, but the polymerization may be carried out in two or more steps in this stage. Further, prior to the full-scale polymerization, a prepolymerization treatment may be carried out in which the catalyst is contacted with a small amount of propylene in advance for the purpose of improving the catalytic activity, improving the bulk density, improving the fluidity and the like. As an example of the prepolymerization treatment, for example, Japanese Patent Publication No. 57-452
The process shown in No. 44 can be exemplified. The pre-stage polymerization can be carried out in the liquid phase or the gas phase in the presence or absence of an inert solvent. A suitable amount of each catalyst component to be used can be appropriately selected depending on its type and the like. In the previous stage of polymerization, a crystalline polymer or copolymer of propylene is produced in order to obtain a block copolymer having high rigidity. As a copolymerization component for producing a copolymer, α-olefins other than propylene, for example, ethylene, 1-butene, 1
-Pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene and the like having 2 to 1 carbon atoms.
0 can be exemplified.

The polymerization temperature for producing the polymer can be appropriately selected, for example, from about 50 to about 100 ° C.
Preferably, it can be about 60 to about 90 ° C. Also, the polymerization pressure can be appropriately selected, for example, from about 1 to about 200 kg / cm.
An example is a polymerization pressure of ² G, preferably about 1 to about 100 kg / cm ² G. When performing liquid phase polymerization, propylene may be used as the liquid medium or an inert solvent may be used as the liquid medium. Examples of such an inert solvent include, for example, propane, butane, pentane, hexane, heptane,
Typical examples include octane, decane, and kerosene.

In the subsequent polymerization step, random copolymerization of propylene with other α-olefin is carried out in the presence of the catalyst-containing propylene crystalline polymer or copolymer obtained in the previous step. This random copolymerization is usually performed subsequent to the preceding polymerization step for producing a crystalline polymer or copolymer of propylene. Random copolymerization can also be performed in a liquid phase or a gas phase. In particular, when gas phase polymerization is adopted, the copolymer is entirely incorporated in the block copolymer, so that the yield with respect to the consumed olefin is high, which is industrially advantageous. Other α-olefins used in random copolymerization include ethylene, 1-butene, 1-pentene,
Examples include 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene and the like. Preferred is ethylene or a combination of ethylene and a C4 to C5 α-olefin.

If necessary, the polypropylene resin composition of the present invention contains EPR, EPDM, polyethylene and E.
BR, polybutene-1 and the like may be included. Further, the polypropylene resin composition of the present invention may contain additives such as various stabilizers, pigments, dispersants and nucleating agents, if necessary.

[0041]

EXAMPLES Next, the present invention will be specifically shown by Examples and Comparative Examples, but the present invention is not limited to the following Examples. In addition, the following reagents were used in the following Examples and Comparative Examples. Metallic magnesium: Granular (average particle size 350 μm) Ethanol: Wako Pure Chemical Industries, Ltd., reagent special grade Iodine: Wako Pure Chemical Industries, Ltd., reagent special grade

Examples 1 to 3 and Comparative Examples 1 to 2 (1) Preparation of solid product A glass reactor equipped with a stirrer (internal volume of about 6 liters) was sufficiently replaced with nitrogen gas, and about 2430 g of ethanol and iodine were added. 16 g and 160 g of metallic magnesium were added, and the mixture was reacted under heating under reflux conditions with stirring until the generation of hydrogen gas stopped, and a solid reaction product was obtained. The reaction liquid containing this solid product was dried under reduced pressure to obtain a solid product (a). The resulting solid product (a) had a sphericity (S) of 1.20 and a particle size distribution index (P) of 1.8.

(2) Preparation of solid catalyst component In a glass three-necked flask (internal volume: 500 ml) sufficiently replaced with nitrogen gas, 16 g of the solid product (a) (not crushed), 80 ml of purified heptane, and four 2.4 ml of silicon chloride and 2.3 ml of diethyl phthalate were added. Maintaining the system temperature at 90 ° C, stirring titanium tetrachloride 7
After adding 7 ml and reacting at 110 ° C. for 2 hours, solid components were separated and washed with purified heptane at 80 ° C. Further, 122 ml of titanium tetrachloride was added, and the mixture was reacted at 110 ° C. for 2 hours and then thoroughly washed with purified heptane to obtain a solid catalyst component (A).

(3) Polymerization of Propylene 30 g of polypropylene powder was placed in an autoclave made of styrene steel (internal volume of about 5 liters), the system was sufficiently replaced with nitrogen gas, and 2.0 mmol of triethylaluminum and diphenyldimethoxysilane were added. 0.5 mmol and the solid catalyst component (a) was charged 0.01 mmol in terms of titanium atom, hydrogen was introduced 0.7 Kg / cm ² G and propylene 27.3 kg / cm ² G, the total pressure 2
Polymerization was carried out at 80 Kg / cm ² and 70 ° C. for 1 hour. Subsequently, after purging the reaction gas in the system, ethylene and propylene were fed at the same volume ratio, and the hydrogen amount was adjusted so that the intrinsic viscosity shown in Table 1 was obtained.
The polymerization time was changed at 0.0 Kg / cm ² , and the copolymerization part ratio shown in Table 1 was adjusted to obtain a polypropylene resin.

Comparative Example 3 (1) Preparation of solid catalyst component 30 g anhydrous magnesium chloride, purified n-heptane 1
50 ml and 6 times mol of ethanol with respect to magnesium chloride were introduced into a glass reactor equipped with a stirrer, which was sufficiently replaced with nitrogen gas, and the mixture was heated and stirred under reflux conditions for 2 hours. Then, this reaction solution was cooled to -20 ° C. and titanium tetrachloride 1
After pressure-feeding to a glass reactor equipped with a stirrer containing 500 ml and gradually warming to room temperature with stirring, di-n-
Add 160 ml of butyl phthalate and add 2 at 110 ° C.
The mixture was heated and stirred for an hour. The solid component formed was separated, and the solid component was further added to 150 ml of titanium tetrachloride at 110 ° C. for 2 times.
After heating and stirring for a time, it was thoroughly washed with purified n-heptane to obtain a solid catalyst component. (2) Polymerization of Propylene Polymerization was carried out in the same manner as in Example 1 using the obtained solid catalyst component to obtain a polypropylene resin.

Using the polypropylene resins obtained in Examples 1 to 3 and Comparative Examples 1 to 3, the pentad fraction (m
mmm%), main elution peak position (Tm
ax) (° C.) and full width at half maximum (σ) (degrees) of the main elution peak,
The intrinsic viscosity [η] (dl / g) was determined based on the following measuring methods and measuring conditions. The results are shown in Table 1.

As a pentad fraction measuring instrument, JNM-EX400 ( ¹³
It was measured under the following conditions using a C nuclear resonance frequency of 100 MHz. Measurement mode: Scalar decoupling method Pulse width: 9.0 μs (45 °) Pulse repetition time: 4 s Accumulation number: 10,000 times Solvent: 1,2,4-Trichlorobenzene / deuterated benzene mixed solvent (90/10% by volume) Sample concentration: 200 mg / 3.0 ml Solvent measurement temperature: 130 ° C. In this case, the pentad fraction was determined by measuring the split peak in the methyl group region of the ¹³ C-NMR spectrum.
In addition, the attribution of the peak of the methyl group region is "Macromolecul
es, 13 (2), 267 (1980) (A. Zambelli et al.) ”.

Tmax and σ were measured under the following conditions. Solvent: Orthodichlorobenzene Flow rate: 2 ml / min Temperature rising rate: 20 ° C./hr Detector: Infrared detector for liquid chromatography Measured wave number: 3.41 μm Column: 1.07 cmφ × 30 cm Filler: Chromosolve P concentration: 7 0.5 mg / 20 ml Injection volume: 2 ml Column temperature distribution: Within ± 0.2 ° C In this case, the sample solution was introduced into the column under the conditions of 135 ° C and then cooled at 2 ° C / hr to use the polymer as the packing material. After adsorption and cooling to room temperature, the column temperature was raised under the above conditions, and the concentration of polymer eluted at each temperature was detected by an infrared detector.

Further, 0.1% of phenolic antioxidant and 0.1% of calcium stearate were added to the obtained resin and pelletized by a 20 mm uniaxial granulator, followed by press plate molding (molding temperature 220 C., cooling temperature 30.degree. C.), a sample for measuring physical properties was prepared, and physical properties were measured. The physical properties are measured by tensile modulus (Kg / cm ² ), heat distortion temperature (deflection temperature under load) (HDT) (° C) and IZ.
The OD impact strength (−20 ° C.) was used. The results are shown in Table 1. The evaluation of each physical property was performed by the following methods.

Tensile modulus was measured according to JIS-K7113. It was measured according to HDT JIS-K7207. The measurement sample was used without annealing, and the bending stress applied to the sample was 4.6 Kg / cm ² . IZOD impact strength It was measured according to JIS-K7110.

[0051]

[Table 1]

[0052]

As described above, the polypropylene resin of the present invention and the composition thereof have extremely high rigidity, heat resistance and impact resistance, and have an excellent balance between them.

[Brief description of drawings]

FIG. 1 Main elution peak position (Tma
x) and the half-value width (σ) of the peak.

[Explanation of symbols]

Tmax ... Main elution peak position σ ... half width of peak

Claims (2)

[Claims] 1. The content of α-olefin units other than propylene is 4 mol% or less, and the pentad fraction measured by ¹³ C-NMR is mm.
The mm fraction is 96.0% or more, and the position (Tmax) of the main elution peak in the temperature rising fractionation method is 1
At a temperature of 18.0 ° C. or higher and a peak half width (σ) of less than 3.4 degrees, an intrinsic viscosity [η] is 0.5 dl / g or more, 2.0 dl /
A polypropylene resin comprising a propylene copolymer having a g or less and having a limiting viscosity [η] of 3.0 dl / g or more. 2. A polypropylene-based resin composition comprising the polypropylene-based resin according to claim 1.