JPH10195259A - Ethylene-alpha olefin-nonconjugated diene copolymer composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an ethylene-α-olefin-nonconjugated diene copolymer composition high in hardness, excellent in kneading processability, extrusion processability, rolling processability, tensile strength and compression set in spite of the high hardness. SOLUTION: This ethylene-α-olefin-nonconjugated diene copolymer composition comprises (A) an ethylene-α-olefin-nonconjugated diene copolymer having the weight ratio of ethylene/α-olefin of 40/60 to 70/30, 1-50 iodine value, 0-160 Money viscosity and J0,000-1,000,000 weight-average molecular weight and (B) an ethylene-α-olefin-nonconjugated diene copolymer having the weight ratio of ethylene/α-olefin of 70/30 to 90/10, 1-50 iodine value, 0-160 Money viscosity and 10,000-1,000,000 weight-average molecular weight in the weight ratio of the components A/B of 30/70 to 70/30 and that of ethylene/α-olefin of 50/50-70/30 and has >=130 deg.C melting point of crystal part composed of ethylene chain, 5-40 iodine value and 20-150 Money viscosity by DSC measurement.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to an ethylene-α-olefin-non-conjugated diene copolymer composition, and more particularly, to two specific types of ethylene-α-olefin-
Contains a non-conjugated diene copolymer, has high hardness, good workability, excellent compression set, sealability, shape retention, etc., and is used in a wide range of applications including automotive seal members. To an ethylene-α-olefin-non-conjugated diene copolymer composition.

[0002]

2. Description of the Related Art Ethylene-α-olefin-non-conjugated diene copolymer rubber is excellent in various properties such as heat resistance, ozone resistance and weather resistance. Widely used. In order to enhance the slidability of glass run, the above-mentioned copolymer rubber is subjected to a treatment such as a surface treatment coat. However, this method has problems such as an increase in cost due to treatment and a decrease in slidability due to deterioration of surface treatment. Therefore, there is a demand for a highly hardened rubber that does not need to be subjected to a surface treatment.

[0003] In addition to the above properties, the above-mentioned copolymer rubber must also have excellent kneading workability, roll workability, extrusion workability, etc. in addition to the performance as a rubber. . In particular, during kneading and extrusion, so-called `` bumps '' and `` gels '' are less likely to occur, and the extruded material has good skin, to improve the appearance of rubber and enhance commercial value, Strictly required.

[0004] Under such circumstances, for example, in order to increase the hardness of a normal ethylene-α-olefin-non-conjugated diene copolymer rubber, a method of blending a normal carbon black and an oil can be mentioned. However, according to this method, the viscosity of the compound increases, and during kneading and extrusion, burns and bumps are generated, and the appearance of the rubber is deteriorated. Further, when the hardness is increased by using a low-viscosity ethylene-α-olefin-non-conjugated diene copolymer rubber, even if there is no problem in kneading and extrusion workability, deterioration in physical properties, particularly tensile strength. However, there is a problem that the compression set is reduced.

[0005]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and has an ethylene-α-olefin-nonconjugated diene copolymer having a low ethylene content.
By blending an ethylene-α-olefin-non-conjugated diene copolymer having a high ethylene content and crystallinity, it has high hardness, and even with high hardness, kneading processability, extrusion processability, It is an object of the present invention to provide an ethylene-α-olefin-non-conjugated diene copolymer rubber composition which is excellent in roll processability and also excellent in tensile strength, compression set and the like.

[0006]

The present invention comprises the following components (A) and (B), wherein the weight ratio of (A) / (B) is 30 / 70-70 / 30, and ethylene / α · The weight ratio of the olefin is 50/50 to 70/30, the melting point of the crystalline portion composed of an ethylene chain measured by a differential scanning calorimeter (hereinafter also referred to as "DSC") is 30 ° C or more, and the iodine value is 5 to 4.
0, Mooney viscosity (ML _{1 + 4} , 100 ° C) 20-15
Ethylene-α-olefin-, which is 0
Non-conjugated diene copolymer composition (hereinafter “copolymer composition”)
Also referred to as). Component (A): weight ratio of ethylene / α-olefin is 40
/ 60-70 / 30, iodine value 1-50, Mooney viscosity (ML _{1 + 4} , 100 ° C) 0-160, weight average molecular weight 10,000-1,000,000, ethylene-α-olefin-non-conjugated Diene copolymer (hereinafter also referred to as “(A) copolymer”). Component (B): weight ratio of ethylene / α-olefin is 70
/ 30-90 / 10, iodine value 1-50, Mooney viscosity (ML _{1 + 4} , 100 ° C) 0-160, weight average molecular weight 10,000-1,000,000, ethylene-α-olefin-non-conjugated Diene copolymer (hereinafter also referred to as “(B) copolymer”).

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The copolymer composition of the present invention is characterized by containing the above specific (A) copolymer and the above specific (B) copolymer. (A) The copolymer is a copolymer rubber having a relatively low ethylene content, and contributes to improvements in compression set and tensile strength at high temperatures. Further, it contributes to improvement of low-temperature characteristics such as compression set at low temperature.
Further, the copolymer (B) is a copolymer rubber having a high ethylene content, forms a chain portion composed of crystalline ethylene, and contributes to improvement of high hardness by containing a large amount of ethylene. . Further, it is a component that contributes to improvement in kneading workability and extrusion workability. As described above, the copolymer composition of the present invention contains the (A) copolymer and the (B) copolymer having the respective characteristics at a specific ratio, and thus the objective high polymer composition is obtained for the first time. Hardness The performance of solid rubber can be obtained.

[0008] α- used in the above components (A) and (B)
As the olefin component, for example, α-
Examples thereof include olefins, specifically, propylene, butene-1, 3-methylbutene-1, and pentene-
1,3-methylpentene-1,4-methylpentene-
Examples thereof include 1,3-ethylpentene-1, hexene-1, octene-1, decene-1, and dodecene-1, and propylene is particularly preferred. These α-olefins are 1
Species can be used alone or in combination of two or more. The non-conjugated diene is not particularly limited, and examples thereof include those used in ethylene-α-olefin-non-conjugated diene copolymer. Specific examples of the non-conjugated diene include 1,4-hexadiene, dicyclopentadiene, methylidene norbornene, 1,9-decadiene, and ethylidene norbornene, and ethylidene norbornene and dicyclopentadiene are particularly preferable.

(A) Copolymer; The weight ratio of ethylene / α-olefin in the copolymer (A) used in the present invention is 40/60 to 70/30, preferably 45/5.
5-65 / 35. When the weight ratio of ethylene / α-olefin is less than 40/60, the dispersion of the filler in the copolymer composition becomes insufficient, the surface appearance is deteriorated, and the strength of the solid rubber is reduced. If it exceeds 30, compression set at low temperatures is impaired. Also,
(A) The copolymer has an iodine value of 1 to 50, preferably 5
~ 40. When the iodine value is less than 1, the tensile strength and the compression set at high temperatures are inferior. On the other hand, when the iodine value exceeds 50, bumps and gels are liable to be produced during kneading and extrusion.
Further, the Mooney viscosity of the copolymer (A) (ML _{1 + 4} , 1
00 ° C) is 0 to 160, preferably 0 to 150. If the Mooney viscosity exceeds 160, kneading processability,
Poor extrusion processability. Further, the weight average molecular weight of the copolymer (A) is 10,000 to 1,000,000, preferably 10,000 to 80.
It is ten thousand. If the weight average molecular weight is less than 10,000, the tensile strength,
The compression set at high temperature is inferior, while when it exceeds 1,000,000,
Poor kneading processability and extrusion processability.

(B) Copolymer; The weight ratio of ethylene / α-olefin in the copolymer (B) used in the present invention is 70/30 to 90/10, preferably 73/2.
7 to 85/15. If the weight ratio of ethylene / α · olefin is less than 70/30, the number of crystal parts composed of ethylene chains decreases, and the hardness of the solid rubber decreases.
On the other hand, if it exceeds 90/10, the compression set at low temperatures is impaired. In addition, bleeding occurs on the unvulcanized and vulcanized surfaces, and the appearance is impaired. Furthermore, roll workability also decreases.

[0011] The (B) copolymer preferably has a crystal part composed of an ethylene chain. For this reason, D
The melting point of the crystal part composed of ethylene chains by SC measurement (hereinafter also referred to as “ethylene crystal melting point”) is preferably 30 ° C. or higher, more preferably 30 to 120 ° C.
When the ethylene crystal melting point is 30 ° C. or higher, high hardness is obtained, and excellent kneading workability and extrusion workability are obtained. If the melting point of the ethylene crystal is lower than 30 ° C., the hardness is lowered, and the kneading processability and the extrusion processability are lowered, which is not preferable.

Further, the iodine value of the copolymer (B) is 1
-50, preferably 5-40. When the iodine value is less than 1, the tensile strength and the compression set at high temperatures are inferior.
Exceeding the range tends to produce bumps and gel during kneading and extrusion. Further, the Mooney viscosity (ML _{1 + 4} , 100 ° C.) of the copolymer (B) is from 0 to 160, preferably from 0 to 150. If the Mooney viscosity exceeds 160, kneading processability and extrusion processability will be poor. further,
(B) the weight average molecular weight of the copolymer is 10,000 to 1,000,000,
Preferably it is 10,000 to 800,000. When the weight average molecular weight is less than 10,000, tensile strength and compression set at high temperature are inferior, and when it exceeds 1,000,000, kneading processability and extrusion processability are inferior.

Method for producing components (A) and (B): The copolymer (A) and the copolymer (B) used in the present invention can be produced by ordinary polymerization. As the polymerization method, for example, in a suitable solvent, in the presence of a Ziegler-Natta catalyst comprising a transition metal compound and an organometallic compound, for example, a catalyst comprising a solvent-soluble vanadium compound and an organoaluminum compound, ethylene, α-olefin And a method of polymerizing a non-conjugated diene while supplying hydrogen as a molecular weight regulator as necessary.

The above-mentioned solvent-soluble vanadium compound is preferably vanadium tetrachloride, vanadium oxytrichloride, and / or a reaction product of these vanadium compounds with an alcohol. In this case, examples of the alcohol include methanol, ethanol, n-propanol, isopropanol, n-butanol, sec-butanol, t-butanol, n-hexanol, n-octanol, 2-ethylhexanol, n-decanol, and n-decanol. Dodecanol and the like can be mentioned, and an alcohol having 3 to 8 carbon atoms is preferable.

The organic aluminum compounds include triethylaluminum, triisobutylaluminum, tri-n-hexylaluminum, diethylaluminum monochloride, diisobutylaluminum monochloride, ethylaluminum sesquichloride, butylaluminum sesquichloride, ethylaluminum dichloride, Butyl aluminum dichloride and the like can be mentioned. These organoaluminum compounds can be used alone or in combination of two or more. Particularly preferred organoaluminum compounds are ethylaluminum sesquichloride, butylaluminum sesquichloride, a mixture of ethylaluminum sesquichloride and butylaluminum sesquichloride, and a mixture of triisobutylaluminum and butylaluminum sesquichloride. Further, as the solvent, a hydrocarbon solvent is used, and preferred hydrocarbon solvents include n-pentadiene, n-hexane, n-heptane,
n-octane, isooctane, cyclohexane and the like.

Further, the polymerization conditions are usually at a temperature of 0
１２０120 ° C., Al / V (molar ratio) = 4〜50, polymerization time 5 seconds〜1 hour.

Copolymer composition; the weight ratio of component (A) / component (B) in the copolymer composition of the present invention is 30.
/ 70-70 / 30, preferably 40 / 60-70 / 3
0. When the weight ratio is less than 30/70, the compression set at low temperature of the composition is impaired, and the roll processability is reduced. On the other hand, when the weight ratio is more than 70/30, the hardness, compression set due to high temperature, and tensile strength are reduced. .

The weight ratio of ethylene / α-olefin in the copolymer composition of the present invention is from 50/50 to 70/3.
0, preferably 55 / 45-70 / 30. If the weight ratio is less than 50/50, the extrusion processability is poor,
On the other hand, if it exceeds 70/30, the permanent set at low temperature is reduced. Further, the melting point of the crystalline portion composed of an ethylene chain by DSC measurement in the copolymer composition is 30 ° C or higher, preferably 30 to 120 ° C. Ethylene crystal melting point is 30
If the temperature is lower than 0 ° C., the hardness is reduced, and the kneading processability and the extrusion processability are undesirably reduced. This ethylene crystal melting point is preferably derived from the (B) copolymer.

Further, the iodine value derived from the content of the non-conjugated diene in the copolymer composition of the present invention is 5 to 40, preferably 10 to 40. If the iodine value is less than 5, compression set at high temperature is impaired, and tensile strength is impaired,
Since the crosslinking speed is low, the productivity is low. On the other hand, when the iodine value of the composition exceeds 40, bumps and gels are easily generated during kneading and extrusion. Further, the Mooney viscosity (ML _{1 + 4} , 10
0 ° C.) is from 20 to 150, preferably from 40 to 150. In this case, if the Mooney viscosity is less than 20, roll processability is inferior, tensile strength, compression set at high temperatures are reduced,
On the other hand, if it exceeds 150, so-called bumps and gels are often generated during kneading and extrusion, and the extruded skin is inferior.

The weight average molecular weight of the copolymer composition of the present invention is preferably 10,000 to 1,000,000, and more preferably 100,000 to 800,000. When the weight-average molecular weight is in this range, excellent tensile strength, high-temperature compression set, kneading workability and extrusion workability are excellent.

Method for producing copolymer composition: The copolymer composition of the present invention may be prepared by any method as long as a good dispersion of each component can be obtained.
The method is preferred, the method is preferably, and the method is more preferred. According to the method, the composition of the present invention, which is more excellent, can be obtained. A method of mixing a (A) copolymer solution and a (B) copolymer solution and then removing the solvent to obtain a solid rubber composition. One of the copolymer (A) and the copolymer (B) is polymerized in the first reactor using two reactors connected in series, and the polymerized copolymer is produced in the second reactor. And producing the solid rubber by removing the solvent after producing the second copolymer by polymerizing the other copolymer in the second reactor. In addition,
The characteristic value of the other copolymer component in this method is determined by calculating from the characteristic value of the first copolymer component and the characteristic value of the copolymer composition of the final product. A method of obtaining a solid copolymer composition by mixing (A) copolymer and (B) copolymer in a solid state with a kneading machine such as a Banbury trunk, a roll mixer, an extruder, etc. .

The copolymer composition of the present invention is blended with a crosslinking agent, a filler, a softening agent and the like, if necessary, to form a rubber compound, and then subjected to crosslinking by a generally used method to give a solid rubber. Manufactured. Examples of the crosslinking agent include sulfur such as powdered sulfur, insoluble sulfur, precipitated sulfur, surface-treated sulfur, and colloidal sulfur; inorganic vulcanizing agents such as sulfur chloride, sulfur dichloride, selenium, and tellurium; morpholine disulfides, alkylphenol disulfide , Thiuram disulfides, dithiocarbamates, and other sulfur-containing organic compounds; 1,1-di-t-butylperoxy-3,3,5-trimethylcyclohexane, di-t-butyl peroxide, dicumyl peroxide, t-butylcumyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane,
Organic peroxides such as 1,3-bis- (t-butylperoxy-isopropyl) benzene are exemplified.
These crosslinking agents can be used alone or in combination of two or more. The amount of the cross-linking agent varies depending on the type of the cross-linking agent. For example, in the case of sulfur, based on 100 parts by weight of the copolymer composition,
0.1 to 10 parts by weight, preferably 0.5 to 5 parts by weight.

When sulfur is used as a cross-linking agent, a vulcanization accelerator and a vulcanization accelerator may be further added as required. Examples of the vulcanization accelerator include aldehyde ammonias such as hexamethylenetetramine and acetaldehyde ammonia; diphenylguanidine, di (o
-Tolyl) guanidine, guanidines such as o-tolyl-biguanidine, thiocarbanilide, di (o-tolyl)
Thioureas such as thiourea, N, N'-diethylthiourea, tetramethylthiourea, tolylmethylthiourea, dilaurylthiourea; mercaptobenzothiazole, dibenzothiazole disulfide, 2- (4-
Morpholinothio) benzothiazole, 2- (2,4-dinitrophenyl) -mercaptobenzothiazole, N,
Benzothiazoles such as N'-diethylthiocarbamoylthio) benzothiazole; Nt-butyl-2-benzothiazylsulfenamide, N, N'-dicyclohexyl-2-benzothiazylsulfenamide;
Sulfenamides such as N'-diisopropyl-2-benzothiazylsulfenamide, N-cyclohexyl-2-benzothiazylsulfenamide; tetramethylthiuram disulfide, tetraethylthiuram disulfide, tetrabutylthiuram disulfide, tetramethylthiuram Thiurams such as monosulfide and dipentamethylenethiuram tetrasulfide; zinc dimethylthiocarbamate, zinc diethylthiocarboxylate, di-n-
Carbamates such as zinc butylthiocarbamate, zinc ethylphenyldithiocarbamate, sodium dimethyldithiocarbamate, copper dimethyldithiocarbamate, tellurium dimethylthiocarbamate and iron dimethylthiocarbamate; zinc butylthioxanthate, zinc isopropylxanthate and the like Xanthates and the like. These vulcanization accelerators can be used alone or in combination of two or more. The amount of the vulcanization accelerator is usually 0.1 to 20 parts by weight, preferably 0.2 to 10 parts by weight, based on 100 parts by weight of the copolymer composition.

Examples of the vulcanization accelerating aid include metal oxides such as magnesium oxide, zinc white, litharge, rhododendron, and lead white; and organic acids such as stearic acid, oleic acid and zinc stearate. In particular, zinc white and stearic acid are preferred. These vulcanization accelerators can be used alone or in combination of two or more. The compounding amount of the vulcanization accelerator is usually 1 to 20 parts by weight based on 100 parts by weight of the copolymer composition.

When an organic peroxide is used as a crosslinking agent, a crosslinking aid can be further added as necessary. Examples of the crosslinking assistant include sulfur compounds such as sulfur and dipentamethylenethiuram tetrasulfides; and polyfunctional compounds such as polyethylene dimethacrylate, divinylbenzene, diallyl phthalate, tolyl allyl cyanurate, metaphenylene bismaleimide, and toluylene bismaleimide. Oxime compounds such as p-quinone oxime and p, p'-benzoylquinone oxime. These crosslinking aids can be used alone or in combination of two or more. The compounding amount of the crosslinking assistant is usually 0.1 to 50 parts by weight based on 100 parts by weight of the copolymer composition.

As the filler, for example, SRF, FE
Carbon blacks such as F, MAF, HAF, ISAF, SAF, FT, and MT; and inorganic fillers such as finely divided silica, calcium carbonate, magnesium carbonate, clay, and talc. These fillers can be used alone or in combination of two or more. The amount of the filler is 10
It is usually 10 to 300 parts by weight with respect to 0 parts by weight.

Examples of the softener include process oils such as aromatic oils, naphthenic oils and paraffin oils which are usually used for rubber; vegetable oils such as coconut oil; process oils are preferable, and paraffin oil is particularly preferable. Particularly preferred. These softeners can be used alone or in combination of two or more. The blending amount of the above-mentioned softener is determined based on the copolymer composition 10
It is usually at least 10 parts by weight based on 0 parts by weight.

Further, the copolymer composition of the present invention comprises a reinforcing agent, a moisture absorbent, a plasticizer, an antioxidant, an antioxidant, a heat stabilizer, an ultraviolet absorber, a lubricant, a release agent, a flame retardant, Additives such as antistatic agents, dyes and pigments, and other rubbery or non-rubbery polymers can also be blended. Examples of the other polymer include butyl rubber, natural rubber, polyisoprene rubber, polybutadiene rubber, styrene-butadiene rubber, acrylonitrile-butadiene rubber, and the above-mentioned (A)
Ethylene-α-olefin-non-conjugated diene copolymer other than the components (B) to (B), ethylene-α-olefin copolymer,
Examples include polyethylene and polypropylene. These other polymers can be used alone or in combination of two or more.

There are no particular restrictions on the method and order of blending the above-mentioned various additives with the copolymer composition of the present invention. Known kneaders and extruders can also be used. Usually, after mixing (A)-(B) components, a filler, a softening agent, etc. using a Banbury mixer etc., a crosslinking agent etc. are mixed using a roll mixer.

Next, according to the procedure used in the production of ordinary solid rubber, for example, a method in which the rubber compound is heated and cross-linked in a mold of a known cross-linking device, or the rubber compound is extruded by using an extruder. After molding into a shape, a predetermined solid rubber can be produced by a method of heating in a crosslinking tank or the like. The heating temperature and heating time at the time of crosslinking vary depending on the type of the crosslinking agent and the like, but the heating temperature is usually 150 to 280 ° C, and the heating time is usually 2 to 2.
20 minutes, preferably 3 to 15 minutes.

[0031]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples unless it exceeds the gist of the present invention. In the examples, parts and percentages are by weight unless otherwise specified. Various measuring methods are as follows. (1) Propylene content (%) It was measured by an infrared absorption spectrum method. (2) Melting point of ethylene crystal (° C.) Using DSC220C manufactured by Seiko Electronics Co., Ltd., heating was performed from room temperature to 160 ° C. at a rate of 20 ° C./min.
After cooling at −110 ° C. at a rate of 10 / min, holding at −110 ° C. for 10 minutes, and heating again to 160 ° C. at a rate of 20 ° C./min, the second time The endothermic peak during heating of JIS K
The melting point was determined according to 7121. (3) Iodine value It was measured by an infrared absorption spectrum method. (4) Mooney viscosity (ML _{1 + 4} , 100 ° C.) Measurement was performed at a measurement temperature of 100 ° C., a preheating time of 1 minute, and a time of 4 minutes until the viscosity was read.

(5) Weight average molecular weight (Mw) Measured by gel permeation chromatography (GPC) according to the following procedure. (I) GPC count was measured using polystyrene of a known molecular weight (monodisperse polystyrene, manufactured by Tosoh Corporation) at a concentration of 0.02%, and its molecular weight M (Mw and Mn) and EV (Elution Volume) were measured. A correlation diagram calibration curve is prepared. (Ii) The GPC count of the sample is measured, and the Mw of the sample is determined from the above-mentioned correlation diagram calibration curve. In this case, preparation of a sample and measurement of GPC were performed as follows.

Sample preparation: (a) A sample was taken in an Erlenmeyer flask together with o-dichlorobenzene so as to have a concentration of 0.15%, and then an antioxidant (2,6-di-t-butyl-p) was added. -Cresol)
Is added in an amount of 0.08% based on the total amount of the sample and the solvent. (B) This Erlenmeyer flask is heated to 135 ° C., stirred for about 30 minutes to dissolve the sample, and then filtered. (C) The filtrate is subjected to GPC measurement. GPC measurement; (a) Apparatus: 150CV type, manufactured by Water Corporation (b) Column: 4 SHOdex (c) Sample solution volume: 500 μl (d) Temperature: 135 ° C. (e) Flow rate: 1 ml / min

(6) Roll workability Using a test roll outer diameter of 250 mm, a roll surface temperature of 5 mm
At 0 ± 5 ° C. and a roll gap of 2 ± 0.1 mm, the biteability of the roll when the rubber compound was passed through the roll was observed. ；: Excellent. Δ: normal ×: inferior

(7) Characteristics Tensile test Tensile strength was measured according to JIS K6251. Hardness test According to JIS K6301, a spring hardness test A-type hardness was measured. Compression set The compression set at 70 ° C. for 22 hours was measured according to JIS K6254. (8) Gelation time (second) Using a sample obtained by kneading the rubber compound shown in [I] of Table 1, a stress relaxation measuring device [JS manufactured by Nippon Synthetic Rubber Co., Ltd.
R elastograph, see Japanese Patent Publication No. 5-25059)
At 130 ° C. and at a shear strain rate of 5 seconds each, the rise time of the torque was measured and defined as the gel time.

Examples 1 to 3 and Comparative Examples 1 to 5 The copolymers of Examples 1 to 3 and Comparative Examples 3 to 5 in Tables 2 to 3
It is a copolymer composition obtained by the method of the method for producing a copolymer composition. Using the copolymers shown in Tables 2 and 3,
After preparing a rubber compound shown in [I] of Table 1, using a BR type Banbury mixer (content 1.7 liter),
Compound (i) was obtained by kneading at 100 rpm for 3 minutes at a rotation speed of 70 rpm. To the compound (i), additives shown in [II] in Table 1 were blended, and a 10-inch roll mixer maintained at 50 ° C. was used, and the number of rotations of a front roll (rpm) / the number of rotations of a rear roll (rpm) was used. = 22/20 and kneading for 30 minutes to obtain compound (ii). Thereafter, crosslinking was performed at 170 ° C. for 20 minutes using a press to obtain a solid rubber. Tables 2 and 3 show the results of evaluation of the obtained solid rubber.

[0037]

[Table 1]

The additives used in Table 1 are as follows. (* 1) Asahi Carbon Co., Ltd., Asahi 50HG (* 2) Idemitsu Kosan Co., Ltd., Diana Process Oil P
W-380 (* 3) Vesta PP (* 4) Tetramethyldisulfide (* 5) Dipentamethylenethiuram tetrasulfide (* 6) Zinc di-n-butyldithiocarbamate (* 7) dibenzo manufactured by Inoue Lime Co., Ltd. Thiazole disulfide

[0039]

[Table 2]

[0040]

[Table 3]

As is clear from Table 2, the copolymer compositions of the present invention (Examples 1 to 3) have high hardness, high tensile strength, low compression set at high temperatures, and excellent roll processability. The gelation time is long. Examples 1 to 3
When this copolymer composition was used for a glass run seal member of an automobile, it was confirmed that the copolymer composition was excellent in sealability and slidability. On the other hand, as is clear from Table 3, Comparative Examples 1 and 2 have the same composition as the average composition of the copolymer compositions of the Examples, but the copolymers of the present invention are used. Unlike compositions, they consist of a single copolymer and therefore have a low ethylene crystal melting point and consequently low hardness. The copolymer composition of Comparative Example 3 has very low propylene content, so that the roll processability is very poor.
Since the copolymer composition of Comparative Example 4 has a high Mooney viscosity, it is inferior in roll processability and has a short gelation time. In the copolymer composition of Comparative Example 5, one of the copolymers has a low iodine value, so that the tensile strength is inferior, and the other copolymer has a high iodine value, so that the gelation time is inferior. In addition, Comparative Examples 1 to
When the copolymer composition of No. 5 was used for a glass run seal member of an automobile, sealability and slidability were poor.

[0042]

The ethylene-α-olefin-non-conjugated diene copolymer composition of the present invention has high hardness and can provide a solid rubber excellent in compression set and tensile strength of a crosslinked product. In addition, the amount of particles and gels generated during kneading is small, and the kneading processability, extrusion processability, and the like are excellent. Therefore, the copolymer composition of the present invention is useful as a high-hardness solid rubber in a wide range of applications, particularly for weather strips for automobiles and glass run seal members, and is particularly useful for glass run seal members.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Takashi Imamura 2--11-24 Tsukiji, Chuo-ku, Tokyo Inside Nippon Gosei Rubber Co., Ltd.

Claims (1)

[Claims] 1. It contains the following components (A) and (B), and the weight ratio of (A) / (B) is 30/70 to 70/3.
0, the weight ratio of ethylene / α-olefin is 50 / 50-
70/30, the melting point of the crystal part composed of an ethylene chain measured by a differential scanning calorimeter is 30 ° C. or more, and the iodine value is 5 to 4
0, Mooney viscosity (ML _{1 + 4} , 100 ° C) 20-15
Ethylene-α-olefin-, which is 0
Non-conjugated diene copolymer composition. Component (A): weight ratio of ethylene / α-olefin is 40
/ 60-70 / 30, iodine value 1-50, Mooney viscosity (ML _{1 + 4} , 100 ° C) 0-160, weight average molecular weight 10,000-1,000,000, ethylene-α-olefin-non-conjugated Diene copolymer. Component (B): weight ratio of ethylene / α-olefin is 70
/ 30-90 / 10, iodine value 1-50, Mooney viscosity (ML _{1 + 4} , 100 ° C) 0-160, weight average molecular weight 10,000-1,000,000, ethylene-α-olefin-non-conjugated Diene copolymer.