JP2001081199A - Method for producing thermoplastic elastomer composition - Google Patents

Abstract

[PROBLEMS] To provide a method for producing a thermoplastic elastomer composition having a good balance among rubber elasticity, mechanical strength, and appearance of an extruded product. A mixture of 30 to 90% by weight of the following component (A) and 10 to 70% by weight of the following component (B) is dynamically heat-treated in the presence of an organic peroxide. 5 to 200 parts by weight of the following component (C) are mixed per 100 parts by weight of the mixture of B). (A) olefin-based rubber (B) propylene-based polymer (C) General formula: A (BA) n and / or (A-
B) A hydrogenated product of a block copolymer having a weight molecular weight represented by n of 150,000 to 450,000 (in the general formula, A represents a polymer block of a monovinyl-substituted aromatic hydrocarbon, and B represents 1,4 bond Is a conjugated diene polymer block having a ratio of 50% or more, and n represents an integer of 1 to 5.)

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a thermoplastic elastomer composition, and more particularly to a method for producing an olefin-based thermoplastic elastomer composition having a good balance of rubber elasticity, mechanical strength, and extrudability. .

[0002]

2. Description of the Related Art In recent years, thermoplastic elastomers which are rubber-like soft materials and which do not require a vulcanization step and have the same moldability as thermoplastic resins have been used in automobile parts, home electric parts, medical equipment, foodstuffs and the like. It is attracting attention and used in the fields of equipment parts, electric wires and miscellaneous goods. By the way, a thermoplastic olefin-based elastomer, which is one of the above thermoplastic elastomers, is excellent in rubber elasticity, but has poor mechanical strength,
There are problems such as that an extruded product having a smooth appearance cannot be obtained and that the shapeability is poor. In order to obtain an excellent extruded product, various improvements have been attempted in, for example, JP-A-5-170930, but the conventional proposal has a problem that rubber elasticity is sacrificed.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a thermoplastic elastomer having a good balance among rubber elasticity, mechanical strength, and appearance of an extruded product. It is to provide a method for producing a composition.

[0004]

As a result of various studies, the present inventors have found that the above object can be easily achieved if specific components are used and a specific blending procedure is adopted. The knowledge was obtained, and the present invention was completed.

That is, the gist of the present invention is that a mixture of 30 to 90% by weight of the following component (A) and 10 to 70% by weight of the following component (B) is dynamically heat-treated in the presence of an organic peroxide. , A component (C) in an amount of 5 to 200 parts by weight per 100 parts by weight of the mixture of the components (A) and (B).

(A) Olefin rubber (B) Propylene polymer (C) General formula: A (BA) n and / or (A-
B) A hydrogenated product of a block copolymer having a weight-average molecular weight represented by n of 150,000 to 450,000 (wherein A represents a polymer block of a monovinyl-substituted aromatic hydrocarbon, and B represents 1,4 (A conjugated diene polymer block having a bond ratio of 50% or more, and n represents an integer of 1 to 5)

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The olefin rubber used as the component (A) in the present invention includes ethylene-propylene copolymer rubber, ethylene-propylene rubber.
Elastic copolymers containing olefin as a main component such as propylene-conjugated diene copolymer rubber (EPDM), ethylene-1-butene-non-conjugated diene copolymer rubber, and propylene-1-butene-non-conjugated diene copolymer rubber It is united. Of these, EPDM is preferred.

[0008] Examples of the non-conjugated diene include dicyclopentadiene, 1,4-hexadiene, cyclooctadiene, methylene norbornene, and ethylidene norbornene, with ethylidene norbornene being particularly preferred. More preferred specific examples of the component (A) include an ethylene content of 55 to 75% by weight and a non-conjugated diene content of 1 to 5.
〜１０10% by weight EPDM. If the ethylene content is less than 55% by weight, extrudability tends to decrease, and if it exceeds 75% by weight, flexibility tends to be lost.

The propylene polymer resin used as the component (B) in the present invention is not particularly limited, but may be polypropylene or polypropylene and α having 2 or more carbon atoms.
-Copolymer resins with olefins are preferred. 2 carbon atoms
Specific examples of the above α-olefin include ethylene, 1-
Butene, 1-pentene, 3-methyl-1-butene, 1-
Hexene, 1-decene, 3-methyl-1-pentene, 4
-Methyl-1-pentene, 1-octene and the like.

[0010] The melt flow rate (MF
R) is usually 0.01 to 20 g / 10 min, preferably 0.1 g as a value at a temperature of 230 ° C. and a load of 2.16 kgf, measured according to JIS K-7210, Table 1, condition 14.
It is in the range of 1 to 10 g / min. If the MFR is out of the above range, a problem may occur in the moldability. Further, the ethylene content is preferably 1% by weight or more, and if the ethylene content is too small, there is a possibility that an extruded product having good appearance may not be obtained.

The hydrogenated product of the block copolymer (hydrogenated product of the vinyl-substituted aromatic hydrocarbon / conjugated diene copolymer) used as the component (C) in the present invention has the general formula: A-
(BA) n and / or (AB) n.
In the general formula, A represents a polymer block of a monovinyl-substituted aromatic hydrocarbon, B represents a conjugated diene polymer block having a 1,4 bond ratio of 50% or more, and n represents an integer of 1 to 5.

The vinyl-substituted aromatic hydrocarbon as a monomer constituting the polymer block (A) is a polymer of styrene or a derivative thereof. Specific examples of the styrene derivative include α-methylstyrene, 1-vinylnaphthalene,
-Vinylnaphthalene, 3-methylstyrene, 4-propylstyrene, 4-cyclohexylstyrene, 4-dodecylstyrene, 2-ethyl-4-benzylstyrene, 4-
(Phenylbutyl) styrene and the like. In particular,
As the polymer component constituting the block (A), a polymer of styrene, a polymer of α-methylstyrene, or a copolymer of styrene and α-methylstyrene is preferable.

The conjugated diene monomer in the polymer block (B) is preferably butadiene, isoprene or a mixture of both. The conjugated diene moiety has a 1,4-vinyl bond content of usually at least 50%, preferably at least 60%. When the 1,4-vinyl bond content of the conjugated diene portion is less than 50%, the obtained thermoplastic elastomer composition tends to lose rubber elasticity.

The proportion of the polymer block (A) in the copolymer is usually 5 to 45% by weight, preferably 10 to 45% by weight.
40% by weight. When the content of the polymer block (A) is less than 5% by weight, the obtained thermoplastic elastomer tends to have poor mechanical strength and rubber elasticity. When the amount of the polymer block (A) is more than 45% by weight, flexibility and rubber elasticity are inferior and bleeding of the softening agent tends to deteriorate.

The weight average molecular weight of the hydrogenated block copolymer (C) must be from 150,000 to 400,000. When the weight average molecular weight is less than 150,000, the mechanical strength of the obtained thermoplastic elastomer is poor, and when it exceeds 450,000, the viscosity is high and the moldability is poor. The preferred weight average molecular weight of the component (C) is in the range of 200,000 to 350,000. The molecular structure of the hydrogenated block copolymer may be linear, branched, radial, or any combination thereof. The above “weight average molecular weight” is a weight average molecular weight in terms of polystyrene measured by gel permeation chromatography (GPC) under the conditions shown in Table 1 below.

[0016]

[Table 1] Equipment: 150C ALC / GPC (MILL
Column: AD80M / S (manufactured by Showa Denko KK) Solvent: o-dichlorobenzene Temperature: 140 ° C Flow rate: 1 ml / min Injection volume: 200 μl Concentration: 2 mg / ml (oxidation) 2,6-di- as an inhibitor
0.2% by weight of t-butyl-p-phenol is added.
Concentration detection is performed by FOXBORO infrared spectrophotometer "MIR".
AN1A "at a wavelength of 3.42 μm. )

The method for producing the above block copolymer is not particularly limited, and for example, Japanese Patent Publication No. 40798/1972.
According to the method described in Japanese Patent Application Laid-Open Publication No. H10-264, it can be obtained by block polymerization in an inert solvent using a lithium catalyst or the like.

The hydrogenation treatment of the block copolymer is described, for example, in JP-B-42-8704 and JP-B-43.
No.-6636, JP-A-59-133203,
Hydrogenation is carried out in an inert solvent in the presence of a hydrogenation catalyst by the method described in JP-A-60-79005. In this hydrogenation, at least 50% by weight, preferably 80% by weight or more of the olefinic double bond in the polymer block B is hydrogenated, and 25% by weight or less of the aromatic unsaturated bond in the polymer block A is 25% by weight or less. Hydrogenated.
Such a hydrogenated block copolymer is a
It is commercially available under the trade name "KRATON-G" from Chemical Company, "Septon" from Kuraray Co., Ltd., and "ToughTech" from Asahi Kasei Corporation.

As the organic peroxide used in the present invention, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, 2,5-dimethyl-2,5-di (t-
Butylperoxy) hexyne-3,1,3-bis (t-
Butyl peroxyisopropyl) benzene, 1,1-di (t-butylperoxy) -3,5-trimethylcyclohexane, 2,5-dimethyl-2,5-di (peroxybenzoyl) hexyne-3, dicumyl par Oxides and the like. Among them, particularly, in terms of odor and scorch, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane or 2,5-dimethyl-2,
5-Di (t-butylperoxy) hexyne-3 is preferred.

In the present invention, a crosslinking assistant can be used in combination. The main crosslinking aids include sulfur, p-quinonedioxime, nitrosobenzene, diphenylguanidine, N-methyl-N-4-dinitrosoaniline, trimethylolpropane-N, and N'-m-phenylenedimaleimide. Peroxy crosslinking auxiliary, divinylbenzene, triallyl cyanurate, ethylene glycol dimethacrylate,
Examples include polyfunctional methacrylate monomers such as diethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, and allyl methacrylate, and polyfunctional vinyl monomers such as vinyl butyrate and vinyl stearate.
By using the compound as described above, a uniform and mild crosslinking reaction can be expected.

In the present invention, a mineral oil-based softener can be used in order to further improve the mechanical properties and processability. Examples of such a mineral oil-based softener include paraffin-based, naphthene-based, and aromatic-based softeners, and paraffin-based softeners are particularly preferable.

In the thermoplastic elastomer composition of the present invention, in addition to the above-mentioned components, other optional components can be blended according to various purposes within a range that does not significantly impair the effects of the present invention. Such components include, for example, fillers, antioxidants, heat stabilizers, light stabilizers, ultraviolet absorbers,
Neutralizing agent, lubricant, anti-fogging agent, anti-blocking agent, slip agent, dispersant, coloring agent, flame retardant, antistatic agent, conductivity-imparting agent, metal deactivator, molecular weight regulator, antibacterial agent, Examples of the additives include various additives such as molds, fluorescent whitening agents, etc., thermoplastic resins and elastomers other than the essential components, fillers, and the like.

Examples of the thermoplastic resin other than the essential components include ethylene / vinyl acetate copolymer, ethylene / acrylic acid copolymer, ethylene / methacrylic acid copolymer, ethylene / acrylic acid ester copolymer, ethylene・ Ethylene such as methacrylic acid ester copolymer α-
Olefin copolymer, polyethylene, polyolefin resin such as polybutene-1 resin, polyphenylene ether resin, polyamide resin such as nylon 6, nylon 66, polyethylene terephthalate, polyester resin such as polybutylene terephthalate, polyoxymethylene homopolymer, Examples thereof include polyoxymethylene resins such as polyoxymethylene copolymers, and polymethyl methacrylate resins.

The elastomers other than the above essential components include, for example, styrene / butadiene copolymer rubber,
Styrene-based elastomers such as styrene-isoprene copolymer rubber are exemplified. Further, examples of the filler include glass fiber, hollow glass sphere, carbon fiber, talc, calcium carbonate, mica, potassium titanate fiber, silica, titanium dioxide, and carbon black.

First, in the present invention, the components (A) and (B) are subjected to a dynamic heat treatment in the presence of an organic peroxide as a mixture. Here, "dynamically heat-treating" refers to kneading in a molten state.

The use ratio of each of the above components is as follows: Component (A) 3
It is necessary to be 0 to 90% by weight and 10 to 70% by weight of the component (B), and it is particularly preferable to be 40 to 85% by weight of the component (A) and 15 to 60% by weight of the component (B). When the use ratio of component (A) is less than 30% by weight (component (B)
When the use ratio of the component (A) exceeds 70% by weight), the flexibility of the composition and the obtained molded article is lost, and when the use ratio of the component (A) exceeds 90% by weight (the use ratio of the component (B) is If it is less than 10% by weight), the moldability deteriorates.

The amount of the organic peroxide to be added is usually 0.005 to 100 parts by weight of the mixture of the components (A) and (B).
3 parts by weight, preferably selected from the range of 0.05 to 2 parts by weight. When the amount of the organic peroxide is less than 0.005 parts by weight, the effect of the crosslinking reaction is small, and when the amount is more than 3 parts by weight, the appearance of the extruded product is deteriorated and is not economically advantageous.

The amount of the crosslinking aid is usually 0.005 per 100 parts by weight of the mixture of the components (A) and (B).
To 4 parts by weight, preferably 0.05 to 3 parts by weight. If the amount of the crosslinking aid is less than 0.005 parts by weight, no effect is exhibited, and if it is more than 4 parts by weight, it is not economically advantageous.

The dynamic heat treatment of the mixture of the components (A) and (B) is performed by using a kneading device such as a Banbury mixer, a mixing roll, a kneader, and an extruder. The temperature is preferably such that the half-life of the organic peroxide used is less than 1 minute, and is usually selected from 130 to 280 ° C. The time is usually selected from a range of 1 to 30 minutes.

Next, in the present invention, it is necessary to mix the component (C) with the mixture of the components (A) and (B). When the component (C) is initially mixed with the components (A) and (B), that is, when the three components (A) to (C) are simultaneously subjected to dynamic heat treatment, the appearance is particularly good. Extruded products cannot be obtained.

The use ratio of the component (C) must be 5 to 200 parts by weight, particularly preferably 10 to 180 parts by weight, per 100 parts by weight of the mixture of the components (A) and (B). . When the use ratio of the component (C) is less than 5 parts by weight, the effect of improving mechanical strength and rubber elasticity is not exhibited,
When the use ratio of the component (C) exceeds 200 parts by weight,
Moldability deteriorates.

The mixing of the component (C) with the mixture of the components (A) and (B) is carried out using the above-mentioned kneading apparatus, and after the completion of the dynamic heat treatment of the components (A) and (B), the component (C) is added. This is done by adding C). The conditions in this case are not particularly limited, and the reaction is usually performed for 1 to 30 minutes under the conditions of the resulting temperature after the heat treatment of the components (A) and (B).

In the present invention, other components such as a mineral oil-based softener can be mixed at any stage, unlike the case of the component (C). For example, the mineral oil-based softener may be oil-extended on the olefin rubber of the component (A) in advance. The amount of the mineral oil-based softener used is determined by the components (A) and (B)
Per 100 parts by weight of the mixture, usually 150 parts by weight or less,
Preferably it is selected from the range of 130 parts by weight or less. When using a mineral oil-based softener, the minimum amount used is usually 0.1 part by weight per 100 parts by weight of the mixture of components (A) and (B).
1 part by weight.

The thermoplastic elastomer composition obtained by the method of the present invention can be easily molded by an apparatus used for ordinary thermoplastic resins, and can be, for example, extruded or injection molded. The compositions according to the invention are particularly suitable for extrusion. In particular, it is suitable for applications in which a soft vinyl chloride resin is used, that is, automotive parts such as weather strips and glass run channels, gaskets for electric refrigerators, packing around windows, and electric wire coating.

[0035]

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. The materials used as the components in the following examples are as follows. In the following, "%" means% by weight.

(A1): Ethylene-propylene-ethylidene norbornene copolymer rubber (ethylene content 70%,
(Ethylidene norbornene content 5.5%), oil extension 100
%, ML = 400, (ML: Mooney viscosity (ML1 + 4
100 ° C), according to ASTM D-927-57T,
same as below)

(A2): Ethylene-propylene-ethylidene norbornene copolymer rubber (ethylene content 66%,
(Ethylidene norbornene content 4.5%), ML = 89

(B): Propylene copolymer (MFR)
(230 ° C, 2.16 kg) = 0.7 g / 10 min)

(C1): block copolymer (block structure: ABA, monomer (A) = styrene, monomer (B) = butadiene / isoprene, Mw = 220,000,
(A) content = 30%, 1,4 bond content in B book = 92%)

(C2): block copolymer (block structure: ABA, monomer (A) = styrene, monomer (B) = butadiene / isoprene, Mw = 230,000
(A) content = 20%, 1,4 bond content in B book = 93%)

(C3): block copolymer (block structure: ABA, monomer (A) = styrene, monomer (B) = isoprene, Mw = 100,000, (A) content = 2
0%, 1,4 bond content in B book = 45%)

(C4): block copolymer (block structure: ABA, monomer (A) = styrene, monomer (B) = butadiene, Mw = 90,000, styrene content = 29
%, 1,4 bond content in B book = 63%)

(D): paraffinic process oil

(E): ethylene-hexane copolymer (M
FR (230 ° C, 2.16 kg) = 2 g / 10 min)

POX: 2,5-dimethyl-2,5-di (t-butylperoxy) hexane

TMP: trimethylolpropane trimethacrylate

The evaluation methods used are as follows (1)-
It is as (4). For the measurements (1) to (3), a 2 mm-thick sheet obtained by injection molding at a cylinder temperature of 220 ° C. and a mold temperature of 40 ° C. was used.

(1) Hardness: Based on JIS K6301 (JIS-A, instantaneous value)

(2) Tensile stress: Based on JIS K6301 (JIS-3 dumbbell, tensile speed 500 mm / mi)
n)

(3) Compression set: JIS K6301
Compliant with (70 ° C, 22 hours, 25% compression)

(4) Surface roughness Ra: JIS B0601
, And molding of the sample and measurement of Ra were performed as follows. That is, using a single-screw extruder φ40 mm manufactured by Mitsubishi Heavy Industries (full flight screw with a compression ratio of 2.2, a flat die having a width of 25 × 1 mm in thickness), a molding temperature below the hopper: 160 ° C, a cylinder: 170 to 190 ° C, :
The molding was performed under the conditions of 180 ° C. and a screw rotation speed of 25 rpm. And about the obtained extruded product surface,
The center line average roughness Ra was measured by a surface roughness meter “Surfcom 570A” manufactured by Toyo Seimitsu Co., Ltd.

(5) MFR: Based on JIS K7210 (230 ° C, 10kg load)

Example 1 A mixture 100 of 75% of the component (A1) and 25% of the component (B)
0.21 part by weight of POX and 0.48 part of TMP per part by weight
Parts by weight and blended for 1 minute with a Henschel mixer, then a co-directional twin screw extruder (“KTX4 made by Kobe Steel”).
4 ", L / D = 41, the number of cylinder blocks = 11), into the first supply port at a rate of 30 kg / h, and further, the component (C1) and the component (D) were added in a weight ratio of 27:40. After mixing in a Henschel mixer at a ratio of 2
The mixture was melt-kneaded at a speed of 0 kg / h and pelletized. Table 2 shows the evaluation results.

The first supply port is provided in the first cylinder block (C1), and the second supply port is
It is provided at the first cylinder block number (C7),
The components supplied to the first supply port are sufficiently mixed before reaching the second supply port, and the components supplied to the second supply port are sufficiently mixed before reaching the discharge port ( same as below).

Example 2 The same operation as in Example 1 was performed, except that the component (C1) was changed to the component (C2). Table 2 shows the evaluation results.

Example 3 The same operation as in Example 1 was performed, except that the component (A1) was changed to the component (A2). Table 3 shows the evaluation results.

Example 4 The same operation as in Example 1 was performed, except that the component (A1) was changed to the component (A2) and the component (C1) was changed to the component (C2). Table 3 shows the evaluation results.

Comparative Example 1 A mixture 100 of 85% of the component (A1) and 15% of the component (B)
0.35 parts by weight of POX and 0.80 TMP per part by weight
Parts by weight and blended with a Henschel mixer for 1 minute. Then, as in Example 1, 40 kg /
h, and the mixture was melt-kneaded without being supplied to the second supply port to form pellets. Table 2 shows the evaluation results.

Comparative Example 2 In Comparative Example 1, the component (E) was further supplied at a rate of 8 kg / h from the second supply port at a rate of 8 kg / h to carry out melt-kneading to form pellets. Table 2 shows the evaluation results.

Comparative Example 3 Mixture 100 of 75% of Component (A1) and 25% of Component (B)
0.21 parts by weight of POX, 0.53 parts by weight of TMP
Parts by weight, 27 parts by weight of component (C2) and 40 of component (D)
Parts by weight and blended for 1 minute with a Henschel mixer, and then, as in Comparative Example 1, 40 kg /
h, and the mixture was melt-kneaded and pelletized. Table 2 shows the evaluation results.

Comparative Example 4 The same operation as in Example 1 was performed, except that the component (A1) was changed to the component (A2) and the component (C1) was changed to the component (C3). Table 3 shows the evaluation results.

Comparative Example 5 The same operation as in Example 1 was performed, except that the component (A1) was changed to the component (A2) and the component (C1) was changed to the component (C4). Table 3 shows the evaluation results.

Comparative Example 6 A mixture 100 of 76% of component (A2) and 24% of component (B)
0.22 parts by weight of POX and 0.50 TMP per part by weight
Parts by weight and blended with a Henschel mixer for 1 minute. Then, as in Example 1, 30 kg was supplied to the first supply port.
/ H, and the component (D) was further supplied from the second supply port so as to be 59 parts by weight, melt-kneaded, and pelletized. Table 3 shows the evaluation results.

[0064]

[Table 2]

[0065]

[Table 3]

<Evaluation of Results> The following is clear from the comparison between the examples and the comparative examples.

(1) Comparative Example 1 lacks the component (C), and is inferior in tensile strength and compression set as compared with Examples 1 and 2.

(2) Comparative Example 2 is a case where component (C) is missing and component (E) is added. Compared with Examples 1 and 2, compression set and appearance (surface roughness) are inferior.

(3) Comparative Example 3 comprises components (C) and (D)
Example 1 and 2
In comparison with, compression set and appearance (surface roughness) are inferior.

(4) Comparative Example 4 is a case where the weight average molecular weight and the 1,4 bond content of the component (C) are lower than the ranges specified in the present invention. Inferior.

(5) Comparative Example 5 is a case where the weight-average molecular weight of the component (C) is lower than the range specified in the present invention. Compared with Examples 3 and 4, compression set and appearance (surface roughness) Inferior.

(6) Comparative Example 6 lacks the component (C), and is inferior to Examples 3 and 4 in tensile strength, compression set and appearance (surface roughness).

[0073]

According to the present invention described above, a method for producing a thermoplastic elastomer composition having a good balance of rubber elasticity, mechanical strength, and appearance of an extruded product is provided. Is big.

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Claims (6)

[Claims] 1. A mixture of 30 to 90% by weight of the following component (A) and 10 to 70% by weight of the following component (B) is dynamically heat-treated in the presence of an organic peroxide. (B)
A method for producing a thermoplastic elastomer composition, which comprises mixing 5 to 200 parts by weight of the following component (C) per 100 parts by weight of the mixture. (A) Olefin rubber (B) Propylene polymer (C) General formula: A (BA) n and / or (A-
B) A hydrogenated product of a block copolymer having a weight molecular weight of 150,000 to 450,000 represented by n (wherein A is a polymer block of a monovinyl-substituted aromatic hydrocarbon, and B is 1,4 bond Is a conjugated diene polymer block having a ratio of 50% or more, and n represents an integer of 1 to 5.) 2. The method according to claim 1, wherein 150 parts by weight or less of a mineral oil-based softener is mixed with 100 parts by weight of the mixture of the components (A) and (B). 3. The block copolymer of component (C) is at least one selected from the group consisting of styrene-butadiene block copolymer, styrene-isoprene block copolymer and styrene-butadiene / isoprene block copolymer. The production method according to claim 1, wherein the production method is a block copolymer. 4. The method according to claim 1, wherein the content of the polymer block (A) in the block copolymer of the component (C) is 25 to 40% by weight. 5. An olefin rubber of component (A) having a content of 250
The method according to any one of claims 1 to 4, which is an ethylene-propylene-ethylidene norbornene copolymer rubber having the above Mooney viscosity ML (1 + 4 100 ° C). 6. The melt flow rate (MF) of the component (B)
R) is 0.01 as a measured value under the conditions specified in the text.
The production method according to any one of claims 1 to 5, wherein the production time is from 20 g / 10 minutes.