JPH0723414B2 - Method for producing ethylene-α-olefin copolymer - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing an ethylene-α-olefin-based copolymer, and more specifically, it has excellent processability, particularly extrusion processability, and good vulcanization physical properties. The present invention relates to a method for producing an ethylene-α-olefin-based copolymer.

(Prior Art) Conventionally, an ethylene-α-olefin-based copolymer or an ethylene-α-olefin-non-conjugated polyene ternary or multi-component copolymer (hereinafter referred to as “ethylene-α-olefin-based copolymer”) Since is excellent in weather resistance and heat aging resistance, it is widely used as a material for automobiles, a building material, a material for electric wires, and a material for modifying polyolefin.

In these applications, it is desirable not only to have excellent vulcanized physical properties, but also to have excellent processability, especially extrusion processability.

Conventionally, ethylene-α has good workability, especially extrusion workability.
Various types of olefin-based copolymer rubbers have been proposed.

For example, Japanese Patent Publication No. 55-33764 proposes a polymer having a wide molecular weight distribution and high ethylene crystallinity.
However, a copolymer rubber having a high ethylene content and a wide molecular weight distribution has high elasticity, and therefore has a large die swell,
Further, there is a drawback that the temperature dependence of the extrusion shape is large, and the polymerization productivity is also poor.

Japanese Examined Patent Publication No. 59-14497 and Japanese Examined Patent Publication No. 46-29012 disclose a method of broadening the molecular weight distribution by a low molecular weight blend to improve the processability.
Japanese Patent Application Laid-Open No. 15472 and Japanese Patent Application Laid-Open No. 57-131212 propose that a mixture of a low molecular component and a high molecular component is produced by series operation of two reactors to improve processability (blending method). ). However, in this blending method, since both are two-component mixtures, it is necessary to blend a large amount of low-molecular components in order to sufficiently improve the workability, and as a result, especially the tensile strength, the settability, etc. It has the drawback of inferior physical properties.

In addition, these methods require a complicated production method such as blending operation, continuous polymerization using a plurality of reactors in series, and batchwise multistage polymerization, which is not economical.

Further, JP-B-39-28303 has succeeded in increasing the yield per unit catalyst and productivity by using a specific silane compound as a catalyst component, but the processability is insufficient.

(Problems to be Solved by the Invention) An object of the present invention is to provide a method for producing an ethylene-α-olefin-based copolymer having excellent processability, particularly extrusion processability, and good vulcanization physical properties in good yield. To do.

(Means for Solving the Problems) The inventors of the present invention have conducted extensive studies to eliminate the above-mentioned drawbacks of the prior art, and as a result, contain a specific vanadium compound, an alkylaluminiminium compound, and a secondary alcohol residue as a catalyst. It has been found that an ethylene-α-olefin copolymer excellent in processability, particularly extrusion processability and vulcanization physical properties is produced only when three kinds of Si compounds are used in combination. The invention was reached.

The present invention includes an alkylaluminum compound, a general formula VOX ₃ (where X is a halogen atom) or a general formula VO (OR ¹ ) nX _3- n.
(Wherein R ¹ is an alkyl residue, X is a halogen atom), and an organic solvent-soluble vanadium compound represented by the general formula Si (OR) jY _4- j (wherein OR is a secondary alcohol residue, Y is a halogen) Atom or alkyl group, j means a real number of 4 ≧ j> 0), in the presence of a Si compound, a non-conjugated polyene compound may coexist, ethylene and α-olefins are copolymerized to form a gel. Ratio of weight average molecular weight Mw and number average molecular weight Mn obtained from permeation chromatograph (Mw / M
It relates to a method for producing an ethylene-α-olefin-based copolymer, characterized in that an ethylene-α-olefin-based copolymer in which n) is 8 to 25 is obtained.

In the method for producing an ethylene-α-olefin-based copolymer of the present invention, as a catalyst, (1) an alkylaluminum compound, (2) a specific organic solvent-soluble vanadium compound and (3) a general formula Si (OR) jY _{4 -} j (symbols in the formula are as defined above) using a combination of three compounds of Si compounds represented by.

In the present invention, the alkylaluminum compound which is the first component of the catalyst is represented by the general formula Al (R ') nX3 _- n (wherein R'is an alkyl group having 1 to 12 carbon atoms, X is a halogen atom, and n is 3 ≧). It means a real number of n> 0).

Examples of these alkyl aluminum compounds include triethyl aluminum, triisobutyl aluminum, tri-2-butyl aluminum, trihexyl aluminum, trialkyl aluminum such as trioctyl aluminum, diethyl aluminum monochloride, diethyl aluminum monobromide, diisobutyl aluminum monochloride. Dialkyl aluminum monohalide such as diisobutyl aluminum monoethoxide, dialkyl aluminum monoalkoxide such as diethyl aluminum monobutoxide, ethyl aluminum sesquichloride, 2-butyl aluminum sesquichloride, alkyl aluminum sesquihalide such as ethyl aluminum sesquibromide, ethyl aluminum dichloride, Ethyl aluminum di And alkyl aluminum dihalides such as Romido like. These organoaluminum compounds are used alone or in combination of two or more.

The organic solvent-soluble vanadium compound, which is the second component of the catalyst in the present invention, is represented by the general formula VOX ₃ (where X is a halogen atom) or the general formula VO (OR ¹ ) nX _3- n (where R ¹ is an alkyl residue). Group, X is a halogen atom), for example, vanadium oxytrichloride, vanadic acid ethoxide dichloride, vanadic acid propoxy dichloride, vanadic acid isopropoxy dichloride, vanadic acid-n-butoxy dichloride, vanadic acid -Sec-butoxide dichloride, vanadic acid-ter-butoxide dichloride and the like. Of these compounds, vanadium oxytrichloride is particularly preferred. These vanadium compounds are used alone or in combination of two or more.

In the present invention, a Si compound represented by the general formula Si (OR) jY _4- j is used as the third component of the catalyst. Aliphatic second in the formula
The primary alcohol residue (-OR) is preferably an alcohol residue having 3 to 20 carbon atoms, particularly 3 to 12 carbon atoms, for example, 2
-Propoxy group, 2-butoxy group, 2-pentoxy group,
3-pentoxy group, 3-methyl-2-butoxy group, 4-
Methyl-2-pentoxy group, 2-heptoxy group, 3-heptoxy group, 2-octoxy group and the like can be mentioned.

The halogen atom represented by Y is preferably a chlorine atom or a bromine atom, and the hydrocarbon group represented by Y is preferably an alkyl group having 1 to 20 carbon atoms. Also j
The value of 4 may be in the range of 4 ≧ j> 0, but is preferably in the range of 4 ≧ j> 1, particularly preferably in the range of 4 ≧ j> 2.

Examples of the Si compound represented by the above general formula include tetraisopropoxysilane, tetra-2-butoxysilane, tetra-2-pentoxysilane, triisopropoxysilane monochloride, tri-2-butoxysilane monochloride, and ethyltri. Examples thereof include isopropoxysilane, methyltriisopropoxysilane, ethyltri-2-butoxysilane, methyltri-2-butoxysilane, phenyltriisopropoxysilane, phenyltri-2-butoxysilane and tetra-2-octoxysilane.
Of these Si compounds, tetraisopropoxysilane and tetra-2-butoxysilane are particularly preferable.

In the present invention, the amount of the vanadium compound used is 0.01 to 50 mmol / m, preferably 0.1 to 5 mmol / m in the reaction medium.

The amount of the alkylaluminum compound used is 1 to 100 mol, preferably 2 to 30 mol, per 1 mol of the vanadium compound.
It is a mole.

The amount of the Si compound used is 0.03 to 2.0 mol, preferably 0.08 to 1.5 mol per mol of the vanadium compound from the viewpoint of processability.
It is a mole.

In the present invention, a catalyst containing the first to third components as essential components is used, but other organic compounds may be used as a co-catalyst, if necessary.

Examples of these cocatalyst compounds include unsaturated dicarboxylic acid anhydrides, unsaturated carboxylic acid compounds, unsaturated kraton compounds, unsaturated cyclic compounds, amines, acid amides, ethers, ketones, aldehydes, and various types. Chelating agent,
Further, halogens, sulfur, metal halides, oxygen, nitro compounds, nitroso compounds, organic nitrates, zincates, N-oxide compounds, P-oxide compounds, azo compounds, organic sulfides, disulfide quinones, acid halides, halogenated carbonization. Examples thereof include hydrogen.

These compounds are added for the purpose of improving polymerization activity, preventing three-dimensional cross-linking gel, adjusting molecular weight distribution, adjusting ethylene chain length, and the like. In order to improve extrusion processability, which is the object of the present invention, Particularly preferred are unsaturated dicarboxylic acid anhydrides, unsaturated carboxylic acid compounds, unsaturated lactone compounds, unsaturated cyclic compounds and halogenated hydrocarbons.

Specifically, maleic anhydride, α- and β-halogenated maleic anhydride, dihalogenated maleic anhydride, citraconic anhydride, phthalic anhydride, tetrachlorophthalic anhydride and the like, cinnamic acid halides (such as chloride and bromide). ), Α- and β-chlorocinnamic acid halides (eg chloride and bromide), α, β-dichlorocinnamic acid chloride, acrylic acid halides (eg chloride and bromide), cinnamic acid alkyl esters, acrylic acid and methacrylic acid. An alkyl ester of crotonic acid halide (eg, chloride and bromide), fumaric acid dihalide (eg, dichloride and dibromide), α- and β-chlorofumaric acid dihalide (eg, dichloride and dibromide), α, β-dichlorofumaric acid dihalide For example dichloride and dibromide), dihalide maleate (e.g. dichlorides and dibromides), dichlorprop maleate dihalides (e.g. dichlorides and dibromides), maleic acid alkyl esters (e.g., dimethyl maleate,
Diethyl maleate, dipropyl maleate, dibutyl maleate, dihexyl maleate, dioctyl maleate), alkyl perchlorcrotonate (eg butyl perchlorcrotonate), 2,3,4,4-tetrachloro-2-butenoic acid Alkyl ester (eg 2,
3,4,4-Tetrachloro-2-butenoic acid butyl) trichloroacetic acid ester (for example, methyl trichloroacetate,
(Trichloroethyl acetate), hexachlorobutadiene and the like.

These compounds are used alone or in combination of two or more. .

The amount of these cocatalyst compounds used is the vanadium compound 1
The amount is 0.1 to 5 mol, preferably 0.2 to 2 mol per mol.

The α-olefin used as the copolymerization monomer is
An α-olefin having 3 to 12 carbon atoms, such as propylene, butene-1, 4-methylpentene-1, hexene-
1, octene-1, etc., propylene, butene-
1 and the like are particularly preferable.

These α-olefins are used alone or in combination of two or more. .

The α-olefin content in the copolymer obtained by the method of the present invention can be selected to any value depending on the application, but is preferably 10 to 60% by weight, particularly preferably 15 to 55% by weight.

When the α-olefin content is less than 10% by weight, the energy loss during kneading becomes large, while when it exceeds 60% by weight, the final product has insufficient physical properties.

In the method of the present invention, a non-conjugated polyene compound may be copolymerized as a copolymerization component mainly for the purpose of sulfur vulcanization.

Examples of the non-conjugated polyene include dicyclopentadiene, tricyclopentadiene, 5-methyl-2,5-norbornadiene, 5-methylene-2-norbornene, 5-
Ethylidene-2-norbornene, 5-isopropylidene-2-norbornene, 5-isopropenyl-2-norbornene, 5- (1-butenyl) -2-norbornene, cyclooctadiene, vinylcyclohexene, 1,5,9-cyclo Dodecatriene, 6-methyl-4,7,8,9-tetrahydroindene, 2,2'-dicyclopentenyl, trans-1,2-divinylcyclobutane, 1,4-hexadiene, 4
-Methyl-1,4-hexadiene, 1,6-octadiene, 1,
7-octadiene, 1,8-nonadiene, 1,9-decadiene, 3,6-dimethyl-1,7-octadiene, 4,5-dimethyl-1,7-octadiene, 1,4,7-octatriene, 5 −
Methyl-1,8-nonadiene, norbornadiene, vinyl norbornene and the like can be mentioned.

Among these non-conjugated polyenes, dicyclopentadiene, 5-ethylidene-2-norbornene and 1,7-octadiene are particularly preferable.

The non-conjugated polyene content in the case of a terpolymer or multi-component copolymer rubber obtained by copolymerizing a non-conjugated polyene can be adjusted depending on the iodine value, but is 5 to 60, preferably 5 to 40.

When the iodine value is less than 5, a sufficient vulcanizing effect is not recognized,
On the other hand, when it exceeds 60, extrudability deteriorates due to generation of gel during polymerization.

In carrying out the method of the present invention, ethylene in which the non-conjugated polyene compound may coexist and the α-olefins are copolymerized in the presence of the catalyst component.
At this time, the copolymerization can be carried out by a solution polymerization method carried out in a good solvent for the copolymer, or a slurry polymerization method using a poor solvent.

Examples of the solvent include n-hexane, n-heptane, n
-Octane, isooctane, kerosene, methylene dichloride, trichloroethylene, tetrachloroethane, perchlorethylene and the like are used. Further, a slurry polymerization method using α-olefin as a solvent is also possible.

The temperature of the copolymerization is -20 to 120 ° C, preferably 20 to 80 ° C.

The copolymerization pressure is 0 to 50 kg / cm ² · G, preferably 2 to 30
It is kg / cm ² · G.

The average residence time in the copolymerization reaction tank is about 5 to 300 minutes, preferably about 10 to 200 minutes.

The molecular weight and ethylene content of the copolymer are controlled mainly by varying the hydrogen concentration or the amount of dialkylzinc used for molecular weight control and the ratio of ethylene to α-olefin in the monomer mixture to be reacted. be able to.

The ethylene-α-olefin copolymer obtained by the method of the present invention has a bimodal molecular weight distribution measured by gel permeation chromatography, and its low molecular weight component is the object of the present invention. It is an important factor for extrusion processability, and the content of the low molecular weight component A (hereinafter referred to as "A value") described below is 10 to 50% by weight, preferably 15 to 40% by weight. This A value is less than 10% by weight or
If it exceeds 50% by weight, good extrudability cannot be obtained.

In addition, the weight average molecular weight / number average molecular weight (Mw / Mn) is 8
-25, preferably 8-20.

When the Mw / Mn is less than 5, the extrusion processability is mainly insufficient, while when it exceeds 25, both the extrusion processability and the physical properties are insufficient.

The A value and Mw / Mn can be arbitrarily adjusted by the alkylaluminum compound / vanadium compound molar ratio, the Si compound / vanadium compound molar ratio, and the like.

The molecular weight of the copolymer obtained in the present invention can be controlled by the Mooney viscosity, but it is generally ML _{1 + 4} , and the Mooney viscosity at 100 ° C. is 10 to 400, preferably 15 to 300. If the Mooney viscosity is less than 10, roll processability is difficult, and the physical properties of the final product are not sufficient.
If it exceeds 0, the extrudability deteriorates.

When the copolymer obtained in the present invention has a high molecular weight, it can be finished as an oil-extended rubber.

The copolymer obtained in the present invention can be used alone or by blending it with other synthetic rubber or natural rubber and vulcanizing it in the field where vulcanized rubber has been conventionally used.

Other synthetic rubbers include, for example, butyl rubber, polybutadiene rubber, high vinyl polybutadiene rubber, styrene-
Butadiene copolymer rubber, polyisoprene rubber, acrylonitrile-butadiene copolymer rubber, silicone rubber, fluorine rubber, acrylic rubber, and other ethylene-α-olefin copolymer rubbers having different Mooney viscosity, copolymer composition, molecular weight, etc. Can be mentioned.

The copolymer obtained in the present invention can be used as a mixture with a synthetic resin such as a thermoplastic resin.

Examples of the thermoplastic resin include polyethylene and polypropylene (including a homopolymer or a copolymer such as ethylene and butene-1).

The amount of the copolymer obtained in the present invention added to the rubber or resin is 20% by weight or more, preferably 30% by weight or more.

Examples of the vulcanizing agent used when compounding the vulcanized rubber include peroxide, sulfur, sulfur monochloride, sulfur dichloride, morpholine disulfide, alkylphenol disulfide, tetramethylthiuram monosulfide, tetramethylthiuram disulfide, dimethyldithiocarbamine. Examples thereof include sulfur compounds such as selenium acid, and metal compounds such as magnesium oxide, zinc white, and red lead. The amount of sulfur used is 0.1 to 10 parts by weight, preferably 0.5 to 5 parts by weight, per 100 parts by weight of the rubber component.

In addition, a vulcanization accelerator may be used as needed when compounding the vulcanized rubber.

Examples of the vulcanization accelerator include N-cyclohexyl-2-
Benzothiazole-sulfenamide, N-oxydiethylene-2-benzothiazole-sulfenamide, N,
N-diisopropyl-2-benzothiazole-sulfenamide, 2-mercaptobenzothiazole, 2- (2,
4-dinitrophenyl) mercaptobenzothiazole,
2- (2,6-diethyl-4-morpholinothio) benzothiazole, benzothiazyl-disulfide and other thiazoles, diphenylguanidine, triphenylguanidine, di-o-tolylguanidine, o-tolylbaiguanide, diphenylguanidine phthalate, etc. Guanidines, acetaldehyde-aniline reaction products, butyraldehyde-aniline condensates, hexamethylenetetramine, aldehyde amines such as acetaldehyde ammonia or aldehyde-ammonia, imidazolines such as 2-mercaptoimidazoline, thiocarbanilide, diethylthiourea, dibutylthione. Thiouria series such as urea and di-o-tolylthiourea, tetramethylthiuram monosulfide, tetramethylthiuram disulfide, tetraethylthiuram disulfate , Thiurams such as tetrabutyl thiuram disulfide, dipentamethylene thiuram tetrasulfide, zinc dimethyldithiocarbamate, zinc diethylthiocarbamate, zinc di-n-butyldithiocarbamate, zinc ethylphenylcarbamate, zinc ethylphenyldithiocarbamate , Zinc butylphenyldithiocarbamate, sodium dimethyldithiocarbamate, selenium dimethyldithiocarbamate, tellurium diethyldithiocarbamate and the like, and zanthate such as zinc dibutylxanthate and the like.

The amount of these vulcanization accelerators used is 0.1 to 20 parts by weight, preferably 0.2 to 10 parts by weight, per 100 parts by weight of the rubber component.

Examples of peroxides used for peroxide vulcanization include dicumyl peroxide, 1,1′-di (t-butylperoxy) -3,3,5-trimethylcyclohexane, di (t-butylperoxy) diisopropylbenzene, 2, 5-dimethyl-2,5-di (t-butylperoxy)
Hexane, 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne and the like can be mentioned.

Further, as the vulcanization aid used at this time, for example, sulfur,
Sulfur compounds such as dipentamethylene thiuram tetrasulfide, ethylene dimethacrylate, divinylbenzene,
Diallyl phthalate, metaphenylene bismaleimide,
Polyfunctional monomer such as toluylene bismaleimide, p-
Examples include oxime compounds such as quinonedioxime and p, p'-dibenzoylquinoneoxime. These compounds are used alone or in combination of two or more.

When performing vulcanization as described above, if necessary, an activator,
Additives such as a dispersant, a filler, a softening agent, a plasticizer, a tackifier, a coloring agent, a foaming agent, a foaming aid, a lubricant, and an antioxidant are used.

Examples of the filler include inorganic fillers such as carbon black, white carbon (silicate compound), calcium carbonate, talc and clay, high styrene resin, coumarone indene resin, phenol resin, lignin, modified melamine resin, petroleum resin and the like. Organic fillers may be mentioned.

Of these compounds, inorganic fillers are particularly preferred.

Examples of the softener include petroleum-based softeners such as process oil, lubricating oil, paraffin, liquid paraffin, petroleum asphalt, and petrolatum, coal tar-based softeners such as coal tar and coal tar pitch, castor oil, linseed oil, rapeseed oil. , Fatty oil softeners such as coconut oil, tall oils, sub oils, bees wax, carnauba wax, waxes such as lanolin, ricinoleic acid, palmitic acid, stearic acid, barium stearate, calcium stearate, zinc lanolinate and other fatty acids And synthetic polymeric substances such as fatty acid salts and petroleum resins.

Examples of the plasticizer include phthalic acid ester-based compounds, adipic acid ester-based compounds, sebacic acid ester-based compounds, and phosphoric acid-based compounds.

Examples of the tackifier include coumarone indene resin,
Examples thereof include terpene / phenolic resin and xylene / formalin resin.

As the colorant, inorganic and organic pigments, and as the foaming agent, for example, sodium bicarbonate, ammonium carbonate, N,
N'-dinitrosopentamethylenetetramine, azocarboxamide, azobisisobutyronitrile, benzenesulfonyl hydrazide, toluenesulfonyl hydrazide, calcium amide, paratoluenesulfonyl azide, etc., examples of the foaming aid include salicylic acid, phthalic acid, urea. Etc.

The compound is produced by a known method using, for example, an open roll mill, a Banbury mixer, a kneader or the like.

(Examples) Hereinafter, the present invention will be specifically described with reference to Examples.

Unless otherwise specified,% and parts in the following examples mean weight basis.

Various analytical methods and methods for measuring physical properties in the following examples are as follows.

(1) Mw / Mn According to Takeuchi's "Gel Vermiation Carmatograph" (published by Maruzen Co., Ltd.), it was measured as follows.

(I) A standard polystyrene having a known molecular weight (manufactured by Toyo Soda Co., Ltd., monodisperse polystyrene) is used to obtain a molecular weight M.
And its GPC (Gel Permeation Chromatograph) count are measured, and a correlation curve calibration curve of molecular weight M and EV (Elution Volume) is drawn.

The concentration at this time is 0.02% by weight.

The calibration curve of standard polystyrene is corrected to the calibration curve of EPDM by the universal method.

(Ii) The GPC pattern of the sample is taken by the GPC measurement method, and M is known from the above (i). The sample preparation conditions and GPC measurement conditions in that case are as follows.

Sample preparation conditions: (a) o-dichlorobenzene solvent as an anti-aging agent 2,
6-di-t-butyl-p-cresol 0.08% was added,
Dissolve.

(B) The sample is dispensed into an Erlenmeyer flask together with an o-dichlorobenzene solvent so as to be 0.1%.

(C) The Erlenmeyer flask is heated to 120 ° C. and stirred for about 60 minutes to dissolve it.

(D) The solvent obtained in (c) is applied to GPC. In addition, in the GPC device, it is automatically filtered by a 0.5 μm sintered filter.

GPC measurement conditions: (a) Device: Waters 150C type (b) Column: Toyo Soda Co., Ltd. H type (c) Sample amount: 500μ (d) Temperature: 120 ° C (e) Flow rate: 1 ml / min ( f) Total number of theoretical plates: 1 × 10 ⁴ to 2 × 10 ⁴ (measured value with acetone) (2) A value From the above molecular weight distribution measurement data, the horizontal axis represents the molecular weight and the vertical axis represents the polymer concentration. Make a diagram.

At this time, standardization is performed so that the area of the molecular weight distribution is always constant.

The normalized molecular weight distribution map is waveform-separated into two peaks using a Gaussian function, the area of low molecular weight is W ₁ , the area of both sides of the polymer is W _2, and the A value is calculated based on the following equation.

(3) Mooney viscosity (ML _{1 + 4} , 100 ° C): Preheated for 1 minute, measured for 4 minutes, measured at a temperature of 100 ° C.

(4) Propylene content (%): Measured by infrared absorption spectrum.

(5) Iodine value: measured by titration method.

(6) Tensile strength, elongation, tensile stress, hardness: Measured according to JIS K-6301.

(7) Roll processability of compounded rubber: 50% of compounded compound after kneading with BR type Banbury mixer
It is wound around a 10-inch roll held at ℃ and a nip width of 2 mm, and it is evaluated based on the length of time required for tight winding and whether or not the winding state is tight. The results are shown as excellent, good, good, poor, and bad.

(8) Extrusion test (extrusion amount, shape and die swell): Tube type (diameter 50 mm, screw temperature 70 ° C, head 100 ° C, 30 rpm, Garvey die) according to ASTM D-2230.
Measured by.

Example 1 n-hexane feed rate 8 in an autoclave with a capacity of 20
/ Hour, residence time 45 minutes, gas phase ethylene / propylene molar ratio (C ₂ / C ₃ ) 0.9, gas phase hydrogen concentration 6 mol% and 5-
Ethylidene-2-norbornene (ENB) was fed at a feed rate of 58 g / hour, to which vanadium catalyst 0.68 mmol /
Hexane vanadium oxytrichloride (VOCl ₃ ) was added as an alkylaluminum compound, 4.1 mmol / hexane of ethylaluminum sesquichloride and 0.26 mmol / hexane of tetra-2-butoxysilane as a Si compound, and the polymerization temperature was 41 ° C. Polymerization pressure 6 kg / cm ²
The continuous polymerization reaction was carried out under the conditions of G. A small amount of isopropanol was added as a reaction terminator to the polymerization liquid withdrawn from the reactor, and the solvent was removed by steam distillation to the outside of the system at 60 ° C.
And dried to obtain the copolymer of the present invention. The raw rubber properties of the resulting copolymer (raw rubber) are shown in Table 2.

Then 100 parts of the copolymer (raw rubber), HAF carbon 67.5
Parts, 1 part of stearic acid, 5 parts of zinc white and 35 parts of naphthenic oil at 70 ° C. using a BR type Banbury mixer.
After kneading at 76 rpm for 5 minutes, 1.5 parts of tetramethylthiuram monosulfide, 0.5 parts of 2-mercaptobenzothiazole and 1.5 parts of sulfur were added and mixed for 5 minutes by a 10 inch roll kept at 50 ° C.

At this time, the nip width was 2 mm, and the roll rotation was 22/28 rpm for the front and rear rolls. Table 2 shows the compounding rubber workability of the obtained rubber.

Then, the obtained rubber was vulcanized at a vulcanization condition of 160 ° C. for 30 minutes,
The physical properties of the obtained vulcanized rubber are shown in Table 2.

Examples 2 to 4 Under the polymerization conditions shown in Table 1, the same treatment as in Example 1 was carried out to obtain the copolymer of the present invention. Obtained copolymer (raw rubber)
The raw rubber properties of are shown in Table 2.

Next, using this copolymer (raw rubber), compounding and vulcanization were performed in the same manner as in Example 1, and the compounded rubber processability of the rubber obtained and the physical properties of the vulcanized rubber are shown in Table 2.

Comparative Example 1 The raw rubber properties of the copolymer obtained by treating in the same manner as in Example 1 under the polymerization conditions shown in Table 1 are shown in Table 2.

Then, using this copolymer, compounding and vulcanization were performed in the same manner as in Example 1, and the compounded rubber processability of the rubber obtained and the physical properties of the vulcanized rubber are shown in Table 2.

From the results shown in Table 2, the copolymers obtained in Examples have excellent processability and vulcanized physical properties, while Comparative Example 1
It is shown that the copolymer obtained in 1) is insufficient especially in terms of processability.

(Effects of the Invention) The copolymer obtained in the present invention contributes to improvement in productivity when producing a final rubber product, and its quality, particularly extrusion processability, is excellent.

Therefore, the copolymer obtained in the present invention has a conventional ethylene-
It can be widely used in fields where α-olefin copolymers are used, such as sponges, tires, inner tubes, footwear, cables, electric wire coatings, hoses, belts, resin modification applications, and waterproof sheets. .

[Brief description of drawings]

FIG. 1 is a flow chart of the method for producing an ethylene-α-olefin-based copolymer of the present invention.

Front Page Continuation (72) Inventor Noboru Oshima 2-11-24 Tsukiji, Chuo-ku, Tokyo Within Nippon Synthetic Rubber Co., Ltd. (56) References JP 61-261306 (JP, A) JP 39 28303 (JP, B1)

Claims (1)

[Claims] 1. An alkylaluminum compound having the general formula VOX ₃
(Where X is a halogen atom) or the general formula VO (OR ¹ ) nX
_3- n (wherein R ¹ is an alkyl residue, X is a halogen atom), an organic solvent-soluble vanadium compound and a general formula Si (OR) jY _4- j (wherein OR is an aliphatic secondary alcohol residue) Group, Y is a halogen atom or a hydrocarbon group, and j is 4 ≧ j> 0) in the presence of a silicon compound, ethylene and α-olefin or ethylene and α-olefin and one or more non-conjugated polyene compounds To obtain an ethylene-α-olefin-based copolymer having a ratio (Mw / Mn) of the weight average molecular weight Mw and the number average molecular weight Mn of 8 to 25, which is obtained by gel permeation chromatography. A method for producing an ethylene-α-olefin copolymer.