JPH05306358A - Production of propylene copolymer - Google Patents

Abstract

PURPOSE:To obtain a copolymer excellent in flexibility and processability and having no stickiness by melting and mixing a block copolymer composed of a polypropylene component and a specific propylene-ethylene random copolymer component with an organic peroxide. CONSTITUTION:(A) (i) 1-60(wt.)% polypropylene, (ii) a propylene based block copolymer composed of 99-40% propylene-ethylene random copolymer obtained from mixed monomers consisting of 15-80(mole)% (preferably 15-60%) ethylene based monomer and 85-20% (preferably 85-40%) propylene based monomer, and having <1% rate of a component with <=10,000 molecular weight and >600,000 weight average molecular weight and (B) an organic peroxide (e.g. methyl ethyl peroxide, etc.) are melted and mixed preferably at 180-250 deg.C in the presence of (C) a compound having >=2 radical polymerizable groups in a molecule (e.g. ethylene glycol diacrylate, etc.) to obtain the objective copolymer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a propylene-based copolymer which is excellent in flexibility and processability and has a non-stickiness despite containing a large amount of ethylene-based monomer units.

[0002]

BACKGROUND OF THE INVENTION Since olefinic thermoplastic elastomers have excellent flexibility, low specific gravity and high weather resistance, they are used for various industrial parts including automobile parts such as bumpers. Widely used for home appliances parts. The olefin-based thermoplastic elastomer is generally produced by blending ethylene-propylene rubber (hereinafter, referred to as EPR) or ethylene-propylene terpolymer (hereinafter, referred to as EPDM) and a thermoplastic resin such as polypropylene. Then
Attempts have been made at once to polymerize an EPR component or EPDM component and a thermoplastic resin component such as polypropylene using a highly active titanium catalyst.

However, when the olefinic thermoplastic elastomer is produced by the above-mentioned polymerization, a large amount of low-molecular weight components are by-produced and dissolved in the solvent, the viscosity of the polymerization solution is remarkably increased, and stirring efficiency and removal of heat of polymerization are removed. The effect was reduced, and further, the polymer particles adhered to each other to form a lump, which made separation from the polymerization tank difficult.

Therefore, in order to solve the above problems by increasing the molecular weight and to prevent the deterioration of molding processability caused by increasing the molecular weight, the obtained polymer having a large molecular weight is used as an organic peroxide. There is a proposed method of degrading. That is, in JP-A-58-32610, after polymerizing an ultrahigh molecular weight propylene-ethylene copolymer having an ethylene composition of 5 to 15% by weight and a melt flow rate of 0.01 to 0.3 g / 10 min. , A method of degrading with an organic peroxide is shown.

However, when the inventors of the present invention conducted a supplementary test of the above-mentioned method, the ultra-high molecular weight propylene-ethylene copolymer was obtained in the form of particles. There is a problem that the surface becomes sticky and a film or a sheet causes a blocking phenomenon to make peeling impossible.

[0006]

Therefore, the present inventors have
As a result of examining the cause of the problem of the method of degrading the above ultrahigh molecular weight propylene-ethylene copolymer with an organic peroxide, a large amount of low molecular weight is contained in the ultrahigh molecular weight propylene-ethylene copolymer, It was found that this low molecular weight component is decomposed by the organic peroxide to have a lower molecular weight, which causes stickiness of the molded product.

The inventors of the present invention investigated a method for producing an olefinic thermoplastic elastomer which is excellent in flexibility and processability and has no stickiness in a molded article. By melt-kneading with an organic peroxide using one having a low molecular weight component, it is thought that the above problems can be solved, and also succeeded in synthesizing an ultrahigh molecular weight propylene-ethylene copolymer having a low molecular weight component, The present invention has been proposed.

That is, the present invention is a block copolymer containing a polypropylene component and a propylene-ethylene random copolymer component, wherein the polypropylene component is 1 to 60.
% By weight, the propylene-ethylene random copolymer component is 99 to 40% by weight, and the propylene-ethylene random copolymer component contains 15 units of ethylene-based monomer units.
~ 80 mol%, 85-85 monomer units based on propylene
A propylene-based block copolymer and an organic compound which are composed of a random copolymer containing 20 mol% and have a ratio of components having a molecular weight of 10,000 or less of 1.0% by weight or less and a weight average molecular weight of 600,000 or more. A method for producing a propylene-based copolymer, which comprises melt-kneading with a peroxide.

In the present invention, propylene as a raw material
The ethylene copolymer (hereinafter, simply referred to as "HMPE copolymer") is a polypropylene component and a propylene-
It is a block copolymer composed of an ethylene random copolymer component.

The proportions of the polypropylene component and the propylene-ethylene random copolymer component are 1 to 60% by weight for the polypropylene component and 99 to 40% by weight for the propylene-ethylene random copolymer component.

If the polypropylene component is less than 1% by weight, the strength and heat resistance of the resulting molded product of the propylene-based copolymer will be reduced. Ratio of polypropylene component is 6
If it exceeds 0% by weight, the low-temperature impact resistance of the molded product is deteriorated, and the intended propylene-based copolymer cannot be obtained. The polypropylene component is preferably in the range of 3 to 50% by weight in consideration of mechanical strength, heat resistance, low temperature impact resistance and the like, and when it is 30% by weight or less, the flexibility becomes good.

Further, the ethylene-propylene random copolymer component is 40 to 99% by weight. 40 above
When it is less than wt%, low temperature impact resistance is poor, and when it exceeds 99 wt%, mechanical properties such as strength and heat resistance of the molded product are poor, which is not preferable. The ethylene-propylene random copolymer component is 50 when considering low temperature impact resistance, strength and heat resistance.
It is preferably in the range of to 97% by weight.

The HMPE copolymer used in the present invention includes:
Any one or more of the polypropylene component and the propylene-ethylene random copolymer component, as long as the physical properties of the block copolymer are not impaired, a small amount of other α-olefin,
For example, it may be contained by being copolymerized in the range of 5 mol% or less.

The HMPE copolymer used in the present invention comprises a so-called block copolymer molecular chain in which a polypropylene component and a propylene-ethylene random copolymer component are arranged in one molecular chain, and a polypropylene component and a propylene-ethylene random copolymer. It is considered that the individual copolymer chains of the copolymer components are microscopically mixed to the extent that mechanical mixing cannot achieve.

The content ratio of each of the ethylene-based monomer unit and the propylene-based monomer unit in the propylene-ethylene random copolymer component is
The monomer unit based on ethylene is 15 to 80 mol%, preferably 15 to 60 mol%, more preferably 20 to 50 mol%. 85 to 20 monomer units based on propylene
Mol%, preferably 85 to 40 mol%, more preferably 80 to 50 mol%. When the content ratio of the ethylene-based monomer unit is less than 15 mol% and the content ratio of the propylene-based monomer unit exceeds 85 mol%, the flexibility and impact resistance of the molded article are insufficient, which is preferable. Absent. On the other hand, the content ratio of ethylene-based monomer units is 8
When the content of the propylene-based monomer unit is more than 0 mol% and less than 20 mol%, the strength and heat resistance of the molded product are not sufficient, which is not preferable.

The HMPE copolymer used in the present invention has a weight average molecular weight of 600,000 or more, and generally 1,000,000 to 7%.
It has a molecular weight in the range of 1,000,000, preferably 1.5 to 3,000,000. When the weight average molecular weight is less than 600,000, polymer particles having a high bulk specific gravity cannot be obtained in the above-mentioned ethylene composition, and only a lumpy polymer can be obtained due to adhesion between the polymer particles, which is not preferable. The weight average molecular weight in the present invention is a value measured by gel permeation chromatography (hereinafter, simply abbreviated as GPC) and converted based on a calibration curve obtained with polystyrene.

The HMPE copolymer used in the present invention has a remarkably small amount of low molecular weight components. That is, in the HMPE copolymer used in the present invention, in the elution curve measured by GPC, 1.0% by weight of the components having a molecular weight of 10,000 or less are contained.
Hereafter, it is preferably 0.5% by weight or less. Therefore, even if the decomposition is performed with the organic peroxide, the amount of low molecular weight components in the polymer after the decomposition is extremely small.

The HMPE copolymer used in the present invention can be obtained as a powder by polymerization according to the production method described below. Bulk density of the powder is at 0.35 g / cm ³ or more, take a value in the range of usually 0.35~0.50g / cm ^3.

The HMPE copolymer used in the present invention is obtained as a powder having a relatively narrow particle size distribution. That is, HMPE
The average particle (hereinafter abbreviated as D ₅₀ ) of the copolymer powder is 10
0 μm ≦ D ₅₀ ≦ 800 μm, 1% by weight or less for particles of 100 μm or less and 1% by weight or less for particles of 1000 μm or more.

The HMPE copolymer used in the present invention may be obtained by any method, but the following method is particularly preferably adopted.

The following components A, B and C A. Titanium compound B. Organoaluminum compound C.I. General formula [I] R _n Si (OR ′) _4-n [I] [wherein R and R ′ are the same or different hydrocarbon groups, and n is an integer of 1 to 3. D) after prepolymerization of propylene in the presence of an organosilicon compound represented by the formula [3] in different stages and using different organosilicon compounds in each prepolymerization step. Titanium-containing polypropylene obtained by prepolymerization E. Organoaluminum compound similar to B. F. This is a method of copolymerizing propylene and ethylene in the presence of the same organosilicon compound as in C above. Titanium compound used in the prepolymerization method [A]
As the compound, a compound known to be used for polymerizing an olefin is adopted without any limitation. In particular, a titanium compound containing titanium, magnesium and halogen as components and having high catalytic activity is preferable. Such a titanium compound having a high catalytic activity is obtained by supporting a titanium halide, particularly titanium tetrachloride, on various magnesium compounds. As a method for producing this catalyst, a known method is adopted without any limitation.
For example, JP-A-56-155206, JP-A-56-136806, and JP-A-57-3.
4103, 58-8706, 58-83006, 58-138708, 58-183
709, 59-206408, 59-219311, 60-81208, 60-81
209, 60-186508, 60-192708, 61-211309, 61-2
71304, 62-15209, 62-11706, 62-72702, 62-10
The method shown in 4810 etc. is adopted. In particular,
For example, a method of co-milling titanium tetrachloride with a magnesium compound such as magnesium chloride, a method of co-milling a titanium halide and a magnesium compound in the presence of an electron donor such as alcohol, ether, ester, ketone or aldehyde, Alternatively, a method of bringing the titanium halide, the magnesium compound and the electron donor into contact with each other in a solvent can be mentioned.

Next, as the organoaluminum compound [B], a compound known to be used for polymerization of olefins can be adopted without any limitation. For example, trimethyl aluminum, triethyl aluminum, tri-n propyl aluminum, tri-n butyl aluminum, tri-i butyl aluminum, tri-n hexyl aluminum, tri-
Trialkylaluminums such as n-octylaluminum and tri-ndecylaluminum: Diethylaluminum monohalides such as diethylaluminum monochloride: Alkylaluminum halides such as methylaluminum sesquichloride, ethylaluminum sesquichloride and ethylaluminum dichloride. Be done. Other alkoxy aluminums such as monoethoxydiethylaluminum and diethoxymonoethylaluminum can be used.

Of these, triethylaluminum is most preferred. The amount of the organoaluminum compound used in each prepolymerization step is Al / T based on the Ti atom in the titanium compound.
The i (molar ratio) is 1 to 100, preferably 2 to 20.

Further, as the organosilicon compound [C], the compound represented by the above general formula [I] is adopted without any limitation.
R and R'in the general formula [I] are hydrocarbon groups such as an alkyl group, an alkenyl group, an alkynyl group and an aryl group. Examples of the organosilicon compound preferably used in the present invention are as follows. For example, trimethylmethoxysilane, trimethylethoxysilane, dimethyldimethoxysilane, dimethylethoxysilane, diphenyldimethoxysilane, methylphenyldimethoxysilane, diphenyldiethoxysilane, ethyltrimethoxysilane, methyltrimethoxysilane, vinyltrimethoxysilane, phenyltrimethoxysilane. Examples thereof include silane, methyltriethoxysilane, ethyltriethoxysilane, vinyltriethoxysilane, butyltriethoxysilane, phenyltriethoxysilane and 6-triethoxysilyl2-norbornene.

The amount of the organosilicon compound used in each prepolymerization step is Si / Ti with respect to Ti atoms in the titanium compound.
(Molar ratio) 0.1 to 100, preferably 0.5 to 10
Is.

In the present invention, the above titanium compound is used.
In addition to [A], the organoaluminum compound [B] and the organosilicon compound [C], the following general formula [II] R ″ -I [II] [wherein R ″ is an iodine atom or a hydrocarbon group. ] The HM obtained by using the iodine compound [D]
Not only the bulk specific gravity of the particles of the PE copolymer is increased, but also the amount of low molecular weight components having a molecular weight of 10,000 or less is significantly reduced, and the stickiness of the molded product after decomposition with an organic peroxide is improved. ..

In the general formula [II], the hydrocarbon group represented by R ″ is a hydrocarbon group such as an alkyl group, an alkenyl group, an alkynyl group or an aryl group. Iodine compounds that can be preferably used in the present invention Specific examples are as follows: For example, iodine, methyl iodide, ethyl iodide, propyl iodide, butyl iodide, iodobenzene, p-toluene iodide, etc. Among them, methyl iodide, iodo Ethyl iodide is preferred.The amount of the iodine compound used in each prepolymerization step is I / T based on the titanium atom in the titanium compound.
i (molar ratio), 0.1 to 100, preferably 0.5 to
50.

In the present invention, the term "preliminary polymerization carried out in multiple steps" means the above-mentioned [A], [B], [C] and, if necessary,
Preliminary polymerization of propylene in the presence of each component of [D], the titanium-containing polypropylene obtained, and the further preparation of propylene in the presence of each of the above components [B], [C] and optionally [D]. It means repeating polymerization. The prepolymerization is preferably performed in the range of 2 to 5 times. Each of the above-mentioned components used in each prepolymerization may be added sequentially or may be used as a mixture. The amount of propylene polymerized in each prepolymerization step is 0.1 to 10 per 1 g of the titanium compound.
The range is 0 g, preferably 1 to 100 g, and industrially the range is 2 to 50 g.

Different types of organosilicon compounds are used in each prepolymerization stage. As the organosilicon compound, it is preferable to use a compound in which at least one of R and R ′ in the general formula [I] is a bulky hydrocarbon group, for example, a phenyl group, a cyclohexyl group or a norbornyl group.
It is preferable because an HMPE copolymer containing a small amount of low molecular weight components can be obtained. The order of using the organosilicon compound used in each prepolymerization step is not particularly limited.

In each preliminary polymerization, it is preferable to polymerize propylene alone, but 5 mol% of α-olefins other than propylene such as ethylene, 1-butene, 1-pentene, 1-hexene and 4-methylpentene-1. The following may be copolymerized with propylene. It is also possible to coexist with hydrogen at each prepolymerization stage.

For each prepolymerization, it is usually preferable to apply slurry polymerization, and as a solvent, a saturated aliphatic hydrocarbon or aromatic hydrocarbon such as hexane, heptane, cyclohexane, benzene, or toluene is used alone, or a mixed solvent thereof is used. Can be used. Each prepolymerization temperature is −
A temperature of 20 to 100 ° C., particularly 0 to 60 ° C. is preferable, and each stage of the prepolymerization may be carried out under different temperature conditions. The pre-polymerization time may be appropriately determined depending on the pre-polymerization temperature and the polymerization amount in the pre-polymerization, and the pressure in the pre-polymerization is not limited, but in the case of slurry polymerization, it is generally from atmospheric pressure to 5 Kg / cm. It is about ² G. Each prepolymerization may be carried out batchwise, semi-batchly or continuously. After the completion of each prepolymerization, hexane, heptane,
Saturated aliphatic hydrocarbons or aromatic hydrocarbons such as cyclohexane, benzene, and toluene are preferably washed alone or with a mixed solvent thereof, and the number of washings is usually preferably 5 to 6 times.

After the preliminary polymerization, main polymerization is carried out. The main polymerization is carried out in the presence of the titanium-containing polypropylene, organoaluminum compound and organosilicon compound obtained by the above-mentioned prepolymerization.

As the organoaluminum compound used in the main polymerization, those used in the above-mentioned prepolymerization can be used, most preferably triethylaluminum. The amount of the organic aluminum compound used is 10 to 10 in terms of Al / Ti (molar ratio) with respect to the titanium atom in the titanium-containing polypropylene.
00, preferably 50 to 500.

Further, the organosilicon compound is represented by the general formula
The compound represented by [I] is adopted without any limitation. The amount of the organosilicon compound used in the main polymerization is Si / Ti (molar ratio) with respect to Ti atoms in the titanium-containing polypropylene.
It is 0.1-1000, preferably 0.5-500.

In the main polymerization, propylene is first polymerized, and then propylene and ethylene are copolymerized. Polymerization of propylene may be carried out by feeding in a mixture of propylene and up to 5 mol% of an acceptable α-olefin. As an example of the polymerization conditions of the propylene, the polymerization temperature is preferably as low as possible in order to increase the bulk specific gravity of the HMPE copolymer, and for example, 80 ° C. or less, and more preferably 20 to 70 ° C. It is suitable.
If necessary, hydrogen may be allowed to coexist as a molecular weight modifier. Furthermore, the polymerization may be any method such as slurry polymerization using propylene and ethylene itself as a solvent, gas phase polymerization, solution polymerization and the like. Considering the simplicity of the process, the reaction rate, and the particle properties of the block copolymer produced, slurry polymerization using propylene itself as a solvent is the most preferred embodiment. The polymerization system may be a batch system, a semi-batch system, or a continuous system, and the polymerization may be carried out in two or more stages under different conditions.

Next, propylene-ethylene random copolymerization is carried out. In the propylene-ethylene random copolymerization, propylene-based monomer units are 20 to 85 mol%, preferably 40 to 85 mol% and ethylene-based monomer units are 15 to 80 mol%, preferably 15 to 60 mol%.
Propylene and ethylene may be mixed and used so as to be in the range of mol%. Therefore, it is preferable to select the mixing ratio of propylene and ethylene such that the ethylene concentration in the gas state is 7 to 50 mol%, preferably 10 to 40 mol%. As the other conditions, the same conditions as the above-mentioned polymerization of propylene can be adopted.

In the main polymerization, in order to control the stereoregularity of propylene, electron donors such as ethers, amines, amides, sulfur-containing compounds, nitriles, carboxylic acids, acid amides, acid anhydrides, acid esters, etc. in addition to organosilicon compounds. Can coexist.

After the completion of the main polymerization, the particulate polymer can be obtained by evaporating the monomer from the polymerization system. This particulate polymer has a higher bulk density when subjected to known washing or countercurrent washing with a hydrocarbon having a carbon number of 7 or less.

In the present invention, the HMPE copolymer obtained by the above method is melt-kneaded in the presence of an organic peroxide. By this melt-kneading, a propylene-based copolymer having excellent processability and having an arbitrarily adjusted molecular weight can be obtained.
When performing melt-kneading, the HMPE copolymer and the organic peroxide are mixed, but the mixing method is not particularly limited. For example, a method of mechanically mixing using a blender such as a blender or a mixer, a method of dissolving an organic peroxide in an appropriate solvent and attaching it to the HMPE copolymer, and then mixing the organic solvent by drying the solvent. There is.

As the melt-kneading temperature, a temperature higher than the melting temperature of the HMPE copolymer and higher than the decomposition temperature of the organic peroxide is adopted. However, if the heating temperature is too high, the polymer is thermally deteriorated. Generally, the melting temperature is 170-300.
It is preferable to set the temperature in the range of 180 ° C., particularly 180 to 250 ° C.

Known organic peroxides are generally used in the present invention. As a typical organic peroxide,
Peroxides such as methyl ethyl peroxide and methyl isobutyl peroxide; diacyl peroxides such as isobutyryl peroxide and acetyl peroxide; diisopropylbenzene hydroperoxide and other hydroperoxides; 2,5-dimethyl-2,5- Di- (t-butylperoxy) hexane,
1,3-bis- (t-butylperoxyisopropyl)
Dialkyl peroxide such as benzene; 1,1-di-
t-butylperoxy-cyclohexane, other peroxyketals; t-butylperoxyacetate, t
-Alkyl peresters such as butyl peroxybenzoate; t-butyl peroxy isopropyl carbonate and other percarbonates. The amount of the organic peroxide used varies depending on the melt index set value of the obtained propylene-based copolymer and is not unconditionally determined, but is 0.001 to 1.0 parts by weight based on 100 parts by weight of the HMPE copolymer. Parts, preferably 0.01-
0.5 parts by weight is common.

Further, when the above-mentioned organic peroxide is melted, a compound having two or more radically polymerizable groups in one molecule can be present. By allowing a compound having two or more radically polymerizable groups to exist in one molecule, the molecular chains can be crosslinked, and thereby stickiness and heat resistance can be further improved.

As the compound having two or more radically polymerizable groups in one molecule, known compounds can be adopted without any limitation. Specifically, ethylene glycol diacrylate, diethylene glycol dimethacrylate, ethylene glycol bisglycidyl methacrylate, bisphenol A dimethacrylate, 2,2-bis (4-methacryloyloxyethoxyphenyl) propane, 2,2-bis (3,5- Acrylic acid and methacrylic acid ester compounds such as dibromo-4-methacryloyloxyethoxyphenyl) propane and trifluoromethyl methacrylate; diallyl phthalate, diallyl terephthalate, diallyl isophthalate, diallyl tartrate, diallyl epoxysuccinate, diallyl malate, diallyl chlorendate , Allyl compounds such as diallyl hexaphthalate, diallyl carbonate and allyl diglycol carbonate; aromatic vinyl such as divinylbenzene It can be exemplified Le compounds.

Two radically polymerizable groups are contained in one molecule as described above.
The amount of the compound having one or more compounds is not particularly limited, but is generally 0.1% with respect to 100 parts by weight of the HMPE copolymer.
It is preferably in the range of 01 to 10 parts by weight, more preferably 0.1 to 1.0 parts by weight.

The melt index of the propylene-based copolymer obtained by melt-kneading with the organic peroxide is 0.1 to 1.
00 g / min, and the molecular weight distribution at this time was the ratio of the weight average molecular weight and the number average molecular weight measured by GPC (bar M
W / bar Mn) is 4.0 or less, preferably 3.0 or less.

Further, in the propylene-based copolymer obtained by melt-kneading, formation of low molecular weight components was not substantially observed, and the components having a molecular weight of 10,000 or less measured by GPC were HMPE copolymerized before decomposition. It is 1.0% by weight or less as in the case of coalescence.
It is presumed that this is a result of the decomposition by the organic peroxide selectively progressing with respect to the high molecular weight component.

[0047]

[Effect] The propylene-based copolymer obtained according to the present invention can be easily produced without sticking to the polymerization tank during production in spite of the relatively large amount of ethylene component, and also has an appropriate molecular weight. It has good processability, and even though it has been decomposed with organic peroxide, it has a low amount of low molecular weight components, so the molded product is not sticky, and it is a good product even when processed into a film or sheet. Become.

The propylene-based copolymer obtained by the present invention can be suitably used in various fields in which conventional thermoplastic elastomers are used. For example, in the field of injection molding, bumpers, mudguards, lamp packings for automobile parts, and various packings for home electric appliances, ski shoes, grips, roller skates, etc. can be mentioned. On the other hand, in the field of extrusion molding,
It can be suitably used as various automobile interior materials, various insulating sheets as home electric appliances and electric wire materials, coating materials for cords and cables, waterproof sheets in the field of civil engineering and construction materials, waterproofing materials, joint materials and the like.

[0049]

The present invention will be described below with reference to examples and comparative examples, but the present invention is not limited to these examples.

The measuring method used in the following examples will be described.

1) The weight average molecular weight and the ratio of the molecular weight of 10,000 or less were measured by GPC (gel permeation chromatography) method. Waters GPC-15
O-dichlorobenzene as a solvent at 0C, 135 ° C
I went there. The column used was TSK gel manufactured by Tosoh Corporation.
GMH6-HT, gel size 10-15μ. The calibration curve has a weight average molecular weight of 950,290 as a standard sample.
It was prepared by using polystyrene of 0, 10,000, 50,000, 49.8 million, 2.7 million and 6.75 million.

[0052] 2) the ethylene content of the ethylene content using JEOL GSX-270, ¹³
It measured using the C-NMR spectrometer.

3) Bulk Specific Gravity It was carried out according to JIS K 6721 (1977).

4) Particle size distribution Opening 75,125,250,355,500,71
About 0,1180 μm sieve was filled with about 5 g of the polymer and classified by a sieve shaker for 10 minutes.

5) Flexural Modulus A 127 mm × 12 mm × 3.1 mm test piece was prepared using an injection molding machine, and the test piece was tested according to ASTM D-790.

6) -20 ° C. Izod impact value A 63 mm × 12 mm × 3.1 mm test piece was prepared by an injection molding machine and measured at -20 ° C. according to ASTM D-256.

7) Evaluation of stickiness A sheet having a thickness of about 0.3 mm was formed by a Brabender extruder and cut into 3.0 cm × 3.0 cm 10
The peeled state after stacking the sheets and leaving them for 1 week under a load of 1 kg was judged by the following evaluation method.

A: There is no adhesion between the sheets, and all peeling is good.

B: There are adhesions on a few sheets, but they are peeled off relatively easily.

C: Adhesion is present on 7 or more sheets, and peeling is relatively difficult.

D: Adhesion of each sheet is remarkable and peeling is impossible at all.

Example 1 [Preparation of Titanium Compound] The titanium component was prepared according to the method of Example 1 in JP-A-58-83006. That is, 0.95 g of anhydrous magnesium chloride (10 m
mol), 10 ml of decane, and 4.7 ml (30 mmol) of 2-ethylhexyl alcohol at 125 ° C.
After heating and stirring for 0.5 hour, 0.5% phthalic anhydride was added to this solution.
5 g (3.75 mmol) was added, and the mixture was further stirred and mixed at 125 ° C. for 1 hour to obtain a uniform solution. After cooling to room temperature, 40 ml of titanium tetrachloride kept at 120 ° C
(0.36 mol) was added dropwise over 1 hour. After the charging is completed, the temperature of the mixed solution is kept at 1 for 2 hours.
The temperature was raised to 10 ° C., and when it reached 110 ° C., 0.54 ml (2.5 mmol) of diisophthalate was added, and the mixture was maintained at the same temperature for 2 hours with stirring. After the completion of the reaction for 2 hours, a solid portion was collected by hot filtration and the solid portion was collected for 200 m.
re-suspended in mCl ₂ TiCl ₄ and then again at 110 ° C. for 2
The heating reaction was carried out for a period of time. After the reaction was completed, the solid portion was collected again by hot filtration and washed sufficiently with decane and hexane until no free titanium compound was detected in the washing liquid. The solid Ti catalyst component prepared by the above manufacturing method was stored as a heptane slurry. The composition of the solid Ti catalyst component was 2.1% by weight titanium, 57% by weight chlorine, 18.0% by weight magnesium, and 21.9% by weight diisobutyl phthalate.

[Preliminary Polymerization] Purified heptane (200 ml), triethylaluminum (50 mmol) and diphenyldimethoxysilane (10) were placed in an N ₂ -substituted 1 l autoclave.
mmol, 50 mmol of ethyl iodide, and 5 mmol of solid Ti catalyst component in terms of Ti atom were charged, and then propylene was continuously introduced into the reactor for 1 hour so as to be 5 g per 1 g of solid Ti catalyst component, and the first preliminary polymerization was performed. Was applied. The temperature during this period was kept at 15 ° C. After 1 hour, the introduction of propylene was stopped and the inside of the reactor was sufficiently replaced with N ₂ . The solid portion of the resulting slurry was washed 6 times with purified heptane.

Furthermore, 1 l of this solid component was subjected to N ₂ substitution.
-Charged into an autoclave and purified heptane 200m
1, triethylaluminum 50 mmol, 6-triethoxysilyl 2-norbornene 10 mmol and ethyl iodide 10 mmol were added, and then propylene was further added to solid T.
i catalyst component was continuously introduced into the reactor for 1 hour so as to be 5 g per 1 g of catalyst component, and the second preliminary polymerization was performed. The temperature during this period was kept at 15 ° C. The solid portion of the obtained slurry was washed 6 times with purified heptane to obtain a titanium-containing polypropylene.

[Overlap] 300 l capacity with N ₂ substitution
Into the autoclave, 200 l of liquid propylene was charged, 274 mmol of triethylaluminum and 274 mmol of diphenyldimethoxysilane were charged, the internal temperature of the autoclave was raised to 60 ° C., and the titanium-containing polypropylene obtained by the prepolymerization was converted into titanium atom. As 1.1
mmol charged. Polymerization of polypropylene was carried out at 60 ° C. for 90 minutes. Then, the internal temperature of the autoclave was lowered to 55 ° C., and the supply of ethylene was started. Copolymerization of propylene and ethylene was carried out for 90 minutes while confirming with a gas chromatograph that the ethylene gas concentration in the gas phase was 25 mol%. After the polymerization was completed, unreacted propylene was flushed to obtain white granular polymer particles. The yield was 38 kg, and the polymerization activity at this time was 15200 g-polymer / g-Ti compound. Further, from a separate experiment, since the polymerization activity of polypropylene at 60 ° C. for 90 minutes was 3500 g-polymer / g-Ti compound, it was found that the proportion of the polypropylene component in the polymer was 23 wt%. The results are shown in Table 1.

To the obtained white granular polymer particles, 1,
3-Bis- (t-butylperoxyisopropyl) -benzene was mixed as shown in Table 2, an antioxidant, a heat stabilizer, and a chlorine scavenger were further added thereto, and they were mixed in a Henschel mixer. Then, it was extruded with a 40 mm single-screw extruder so that the resin temperature at the die outlet was 220 ° C. to obtain pellets. The results are shown in Table 2.

Examples 2 and 3 In the polymerization of Example 1, the ethylene gas concentration was adjusted to 15 mo.
The same operation as in Example 1 was performed except that the amounts were 1% and 30 mol%. The results are shown in Tables 1 and 2.

Example 4 In the polymerization of Example 1, the polymerization of polypropylene was changed to 6
The same operation as in Example 1 was performed except that the temperature was 0 ° C. for 30 minutes. The results are shown in Tables 1 and 2.

Example 5 In the polymerization of Example 1, the same operation as in Example 1 was carried out except that hydrogen gas was introduced so that the gas concentration was 0.02 mol% in the copolymerization of propylene and ethylene. I went.
The results are shown in Tables 1 and 2.

Example 6 Example 1 was repeated except that phenyltriethoxysilane was used in place of 6-triethoxysilyl-2-norbornene as the second prepolymerization organosilicon compound in the prepolymerization of Example 1. The same operation was performed. The results are shown in Tables 1 and 2.

Examples 7 and 8 The amount of 1,3-bis- (t-butylperoxyisopropyl) -benzene added to the white granular polymer obtained in Example 1 was changed as shown in Table 2. Except for this, the same operation as in Example 1 was performed. The results are shown in Table 2.

Example 9 In the polymerization of Example 1, polymerization of polypropylene was carried out to 70%.
The same operation as in Example 1 was performed except that the temperature was 120 ° C. for 120 minutes. The results are shown in Tables 1 and 2.

Comparative Example 1 Example 1 except that the prepolymerization of Example 1 was not performed.
The same operation was performed. The results are shown in Tables 1 and 2.

Comparative Example 2 In the copolymerization of propylene and ethylene of Example 1, the same operation as in Example 1 was carried out except that hydrogen gas was charged so that the gas concentration was 1.8 mol%. The results are shown in Table 1. The particles could not be formed into pellets due to marked mutual adhesion of particles.

Comparative Example 3 In the polymerization of Example 1, polypropylene was polymerized at 70 ° C.
And propylene and ethylene for 5 minutes.
The same operation as in Example 1 was performed except that the temperature was 5 ° C. for 30 minutes. The results are shown in Tables 1 and 2.

Example 10 To the copolymer particles obtained in Example 1, 0.5% by weight of ethylene glycol dimethacrylate as a cross-linking aid, 1,
Same as Example 1 except that 3-bis- (t-butylperoxyisopropyl) benzene, antioxidant, heat stabilizer, and chlorine scavenger were added, mixed with a Henschel mixer, and pelletized with an extruder in 40 mm. The operation was performed. The results are shown in Table 2.

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[Table 1]

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[Table 2]

Claims (2)

[Claims] 1. A block copolymer containing a polypropylene component and a propylene-ethylene random copolymer component, wherein the polypropylene component is 1 to 60% by weight and the propylene-ethylene random copolymer component is 99 to 40% by weight.
The propylene-ethylene random copolymer component is composed of a random copolymer containing 15 to 80 mol% of ethylene-based monomer units and 85 to 20 mol% of propylene-based monomer units. And a ratio of components having a molecular weight of 10,000 or less is 1.0% by weight or less, and a propylene block copolymer having a weight average molecular weight of 600,000 or more and an organic peroxide are melt-kneaded. Method for producing propylene-based copolymer. 2. A block copolymer comprising a polypropylene component and a propylene-ethylene random copolymer component, wherein the polypropylene component is 1 to 60% by weight and the propylene-ethylene random copolymer component is 99 to 40% by weight. The propylene-ethylene random copolymer component is composed of a random copolymer containing 15 to 80 mol% of ethylene-based monomer units and 85 to 20 mol% of propylene-based monomer units, and The ratio of the component having a molecular weight of 10,000 or less is 1.0% by weight or less, and the weight average molecular weight of the propylene-based block copolymer and the organic peroxide having a weight average molecular weight of 600,000 or more has 2 radical-polymerizable groups in one molecule. A method for producing a propylene-based copolymer, which comprises melt-kneading in the presence of a compound having one or more compounds.