JPH11293065A - Rubber composition for heat-resistant vibration-insulating rubber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a composition excellent in heat resistance, vibration insulating properties and heat aging resistance by admixing a thermoplastic resin and a reinforcing agent each in a specific amount with an olefinic rubber thereby adjusting the JISA rubber hardness to a specific value. SOLUTION: There is provided a composition comprising 100 pts.wt. of an ethylene/3-20C α-olefin/non-conjugated polyene copolymer rubber containing 50-70 wt.% of ethylene and 2-15 wt.% of a non-conjugated polyene such as an ethylene/propylene/dicyclopentadiene copolymer or the like; 5-40 pts.wt. of a thermoplastic resin having a DSC melting point of 150-200 deg.C such as a crystalline polyolefin resin or the like; 25-70 pts.wt. of a reinforcing agent such as carbon black or the like; 10-50 pts.wt. of a filler; 20-80 pts.wt. of a plasticizer; 0.1-10 pts.wt. of sulfur or a sulfur compound; 0.1-20 pts.wt. of a vulcanizing accelerator; and the like. The vulcanizate has a JISA hardness of 30-70 and an index obtained according to the equation: the index (%)=[E*(1%)/E*(0.1%)]×100 by a torsion-dependency test of the complex modulus E* (%), of at least 90%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rubber composition for heat-resistant and vibration-proof rubber, and more particularly, to a heat-resistant and vibration-proof rubber material that can be suitably used as a vibration-proof rubber material particularly required to have heat resistance in an engine mount of an automobile or the like. The present invention relates to a rubber composition for vibration rubber.

[0002]

2. Description of the Related Art In recent years, physical properties required for vibration-proof rubbers, particularly heat resistance and vibration-proof properties, have become very strict. Currently, natural rubber,
Butadiene rubber, styrene-butadiene rubber, chloroprene rubber, butyl rubber, and the like are used, and two or more kinds of polymers are blended and used depending on the application. However, these polymers basically have poor heat resistance because they have a double bond in the main chain.
Therefore, attempts have been made to control the crosslinking form by examining the type and combination of vulcanization accelerators. Cracks may form on the rubber surface and eventually break. Therefore, improvement of heat resistance has become a problem in vibration-proof rubber.

[0003] The anti-vibration characteristics are important physical properties because they are greatly related to the riding comfort of the car and the muffled sound inside the car.
The engine mount functions as a dynamic damper for the engine transmission to reduce the vibration inside the vehicle due to the input from the road surface.Recently, the low frequency range such as idle vibration, shake, and muffled sound is attenuated to a higher level. Is desired. For example, it is required to reduce the transmission rate in a frequency band of 100 Hz or more for vehicle interior noise such as muffled noise while suppressing vibration transmission in a frequency band of 7 to 15 Hz relating to engine shake.

Therefore, in order to attenuate a low-frequency (7 to 15 Hz) high-amplitude input, the loss tangent (tan δ), which is a measure of the ride quality of an automobile, may be increased.
In the case of a polymer having a large an δ or a compound thereof, the dynamic magnification (dynamic shear elastic modulus / static shear elastic modulus) becomes large, so that there is a problem that a muffled sound is generated during high-speed operation. For this reason, liquid-filled mounts have been commercialized to eliminate both. In this product, the attenuation is expressed mechanically, so that the characteristics required of the rubber are low tan δ, a material whose spring constant does not change with respect to various strains, and heat resistance. Various distortions are input to vibration-proof rubber products. The spring constant of the carbon black compounded system changes greatly due to strain, and ethylene / α
-Olefin / non-conjugated polyene copolymer rubber (EPD
M) The material does not have mechanical strength as a vibration-proof rubber unless a reinforcing agent such as carbon black is added in a larger amount than NR-based (nitrile rubber). Therefore, there has been a demand for a reinforcing polymer having a reinforcing property and having a small change in a spring constant due to strain. Accordingly, a vulcanized rubber molded article that has solved the above-mentioned problems, has excellent properties such as heat resistance and vibration-proof properties, and has a small rate of change in vibration-proof properties due to thermal degradation, that is, has excellent heat aging resistance. The appearance of a rubber composition for heat-resistant and vibration-proof rubber which can be provided has been desired.

[0005]

SUMMARY OF THE INVENTION The present invention is intended to solve the above-mentioned problems associated with the prior art, and has excellent properties such as heat resistance and vibration-proofing properties and heat aging resistance. An object of the present invention is to provide a rubber composition for heat-resistant and vibration-proof rubber capable of providing a vulcanized rubber molded article.

[0006]

The present invention includes the following inventions. (1) For 100 parts by weight of the olefin-based rubber (A),
5 to 40 parts by weight of thermoplastic resin (B) and reinforcing agent (C) 2
5 to 70 parts by weight, rubber hardness is JIS
A rubber composition for heat-resistant vibration-proof rubber having an A hardness of 30 to 70. (2) An index (%) obtained by a strain dependency test of a complex elastic modulus E ^* obtained from a dynamic viscoelasticity test of a vulcanized rubber = [E ^* (1
%) / E ^* (0.1%)] × 100 is 90% or more. (3) The rubber composition for heat-resistant and vibration-proof rubber according to the above (1) or (2), wherein the reinforcing agent is carbon black and / or silica.

(4) The olefin rubber (A) is an ethylene / α-olefin / non-conjugated polyene copolymer rubber comprising ethylene, an α-olefin having 3 to 20 carbon atoms and a non-conjugated polyene. The rubber composition for heat-resistant and vibration-proof rubber according to any one of (1) to (3). (5) The heat resistance according to any of (1) to (4), wherein the thermoplastic resin (B) is a crystalline polyolefin resin having a melting point (Tm) measured by DSC in the range of 150 to 200 ° C. A rubber composition for vibration rubber. (6) The crystalline polyolefin resin is an electron microscope 1
(5) The rubber composition for heat-resistant and vibration-proof rubber according to the above (5), wherein the average particle size determined at a ten thousand-fold level is dispersed in the range of 0.1 to 20 µm.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The olefin rubber (A) used in the present invention includes an ethylene / α-olefin / non-conjugated polyene copolymer rubber, preferably an ethylene / α-olefin / non-conjugated polyene copolymer rubber. A polymer rubber, more preferably an ethylene / α-olefin / non-conjugated polyene copolymer rubber (A ′) composed of ethylene, an α-olefin having 3 to 20 carbon atoms, and a non-conjugated polyene is exemplified. Examples of the α-olefin used in the ethylene / α-olefin / non-conjugated polyene copolymer rubber include propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-heptene, 1-
Octene, 1-nonene, 1-decene, 1-undecene,
1-dodecene, 1-tridecene, 1-tetradecene, 1
-Pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene, 1-eicosene and the like. Among these, propylene, 1
-Butene, 4-methyl-1-pentene, 1-hexene,
1-octene is preferred. That is, ethylene / propylene / non-conjugated polyene copolymer rubber, ethylene / 1-butene / non-conjugated polyene copolymer rubber, ethylene-4-methyl-1-pentene / non-conjugated polyene copolymer rubber, ethylene / 1- Hexene / non-conjugated polyene copolymer rubber and ethylene / 1-octene / non-conjugated polyene copolymer rubber are preferably used.

As the non-conjugated polyene, a cyclic or chain non-conjugated polyene can be used. Examples of the cyclic non-conjugated polyene include 5-ethylidene-2-
Norbornene, dicyclopentadiene, 5-vinyl-2
-Norbornene, norbornadiene, methyltetrahydroindene and the like. Examples of the chain non-conjugated polyene include 1,4-hexadiene, 7-methyl-1,6-octadiene, 8-methyl-4-ethylidene-1,7-nonadiene and 4-ethylidene-1,7-diene. And undecadiene. These non-conjugated polyenes can be used alone or in combination of two or more.

The ethylene content in the ethylene / α-olefin / non-conjugated polyene copolymer rubber (A ′) is usually 50 to 70% by weight, preferably 53 to 68% by weight, more preferably 54 to 65% by weight. The non-conjugated polyene content is usually 2 to 15% by weight, preferably 5 to 10% by weight, more preferably 6 to 9% by weight. The intrinsic viscosity [η] of the copolymer rubber (A ′) measured in decalin at 135 ° C. is usually 1.0 to 5.0 dl / g, preferably 2 to 5.0 dl / g.
４4.5 dl / g. In the present invention, the copolymer rubber (A ′) can be used alone or in combination of two or more.

[0011] Ethylene α-having the above properties
Olefins and non-conjugated polyene copolymer rubbers are described in “Polymer Manufacturing Process” (published by the Industrial Research Institute, pp. 309-330).
)) ”And the like. Examples of the thermoplastic resin (B) used in the present invention include a polyolefin resin, a propylene-based polymer, and a poly-4-methylpentene-1 polymer, and preferably include a crystalline polyolefin resin (B ′). . The crystalline polyolefin resin (B ') has a melting point (Tm) measured by DSC (differential scanning calorimeter) of preferably 150 to 200C, more preferably 160 to 170C. The melting point (T
If m) is less than 150 ° C., the spring constant, which is important as an anti-vibration rubber property, changes due to the softening of the olefin due to the temperature in the engine room of the car. It is difficult to obtain a polymer whose particle size is controlled to 20 μm or less.

Average particle size (determined at 10,000 times level with an electron microscope) of a polyolefin resin (B ') microdispersed in a molten state in an ethylene / α-olefin / non-conjugated polyene copolymer rubber (A') Is preferably 0.1 to 20 μm. When the average particle size is less than 0.1 μm,
The index (%) = [E ^* (1%) / E ^* (0.1%)]
When the value of × 100 is less than 90%, on the other hand, when it exceeds 20 μm, the rubber elasticity decreases. The aspect ratio (major axis / minor axis) of the dispersed particles of the polyolefin resin (B ′) is
Preferably it is 5 or less, more preferably 1-3. When the aspect ratio is 5 or less, the microdispersion of the polyolefin resin (B ′) particles is good. When the crystalline polyolefin resin (B ') is a propylene (co) polymer, its melt flow rate (ASTM D 1238, 230
° C, load 2.16 kg) is usually 0.1 to 50 g / 10 min, preferably 0.5 to 40 g / 10 min, more preferably 1 to 10 g / 10 min.
It is in the range of 30 g / 10 minutes. The crystallinity of the crystalline polyolefin resin (B ′) measured by the X-ray diffraction method is as follows:
Usually it is 20% or more.

In the present invention, the thermoplastic resin (B)
Is 5 parts by weight with respect to 100 parts by weight of the olefin rubber (A).
It is used in an amount of from 40 to 40 parts by weight, preferably from 10 to 40 parts by weight, more preferably from 15 to 30 parts by weight. If the blending amount of the thermoplastic resin (B) is less than 5 parts by weight, the strain dependency increases, while if it exceeds 40 parts by weight, rubber elasticity is significantly impaired.

The reinforcing agent (reinforcing filler) (C) used in the present invention has the effect of increasing the mechanical properties such as the tensile strength, tear strength and abrasion resistance of the vulcanized rubber. Examples of such a reinforcing agent (C) include carbon black and silica which may be subjected to a surface treatment with a silane coupling agent or the like. In the present invention,
If it is carbon black usually used for rubber, its type (for example, SRF, GPF, FEF, MAF, HA
F, ISAF, SAF, FT, MT, etc.), and all can be used. As the reinforcing agent (C), carbon black, silica, or a combination thereof is particularly preferred. In the present invention, the reinforcing agent (C) is used in an amount of 25 to 70 parts by weight, preferably 30 to 60 parts by weight, and more preferably 35 to 100 parts by weight of the olefin rubber (A).
It is used in a proportion of up to 55 parts by weight.

The rubber composition for heat and vibration proof rubber of the present invention must have a rubber hardness of JIS A hardness 30 to 70. If the rubber hardness is less than JIS A hardness 30, the mechanical strength is reduced and the object cannot be supported.
If the hardness exceeds 70, the ability to block vibration is reduced. The rubber composition for heat and vibration proof rubber of the present invention has an index (%) obtained by a strain dependency test of a complex elastic modulus E ^* obtained from a dynamic viscoelasticity test of a vulcanized rubber = [E ^* (1%) / E
^* (0.1%)] × 100 is preferably 90% or more. When the index is less than 90%, the dispersibility of the thermoplastic resin (B), the reinforcing agent (C), and the like is low, and the vibration isolation characteristics and the fatigue resistance are reduced.

In the rubber composition for heat and vibration proof rubber of the present invention, in addition to the above-mentioned components, a foaming agent, a filler, a plasticizer (softening agent), a vulcanizing agent, a vulcanization accelerator may be used, if necessary. Agents, vulcanization aids, foaming aids, processing aids, anti-aging agents, heat stabilizers, weather stabilizers, antistatic agents, colorants, lubricants, thickeners and other rubber compounding agents Can be blended in a range that does not impair the purpose. The filler means a filler having no reinforcing property. This filler is used for the purpose of increasing the hardness of the rubber product or reducing the cost without significantly affecting the strength. Specific examples of such a filler include talc, clay, calcium carbonate and the like. The filler is usually used in a proportion of 10 to 50 parts by weight based on 100 parts by weight of the olefin rubber (A).

As the plasticizer (softening agent), a plasticizer usually used for rubber is used. Specifically, process oil, lubricating oil, paraffin oil, liquid paraffin, petroleum asphalt, vaseline, coal tar, castor oil,
Linseed oil, sub, beeswax, palmitic acid, stearic acid, barium stearate, calcium stearate,
Examples include zinc laurate, atactic polypropylene, and coumaroindene resin. Among them, process oil and paraffin oil are particularly preferably used. The plasticizer is usually 10 to 100 parts by weight, preferably 20 to 80 parts by weight, based on 100 parts by weight of the olefin rubber (A).
More preferably, it is used in a proportion of 30 to 70 parts by weight.

Examples of the vulcanizing agent include sulfur, sulfur compounds, and organic peroxides. Specific examples of the sulfur include powdered sulfur, precipitated sulfur, colloidal sulfur, surface-treated sulfur, and insoluble sulfur. Specific examples of the sulfur compound include sulfur chloride, sulfur dichloride, and polymer polysulfide. Sulfur compounds which release active sulfur at the vulcanization temperature and vulcanize, such as morpholine disulfide, alkylphenol disulfide, tetramethylthiuram disulfide, dipentamethylenethiuram tetrasulfide, and the like can also be used. In the present invention, the sulfur or the sulfur compound is usually 0.1 to 10 parts by weight, preferably 0.5 to 3 parts by weight, based on 100 parts by weight of the olefin rubber (A).
More preferably, it is used in a ratio of 1.0 to 3.0 parts by weight.

When sulfur or a sulfur compound is used as the vulcanizing agent, it is preferable to use a vulcanization accelerator in combination. Specific examples of the vulcanization accelerator include N-cyclohexyl-2-benzothiazolesulfenamide and N-cyclohexyl-2-benzothiazolesulfenamide.
Oxydiethylene-2-benzothiazolesulfenamide, N, N-diisopropyl-2-benzothiazolesulfenamide, 2-mercaptobenzothiazole,
Thiazole compounds such as 2- (2,4-dinitrophenyl) mercaptobenzothiazole, 2- (2,6-diethyl-4-morpholinothio) benzothiazole, dibenzothiazyldisulfide; diphenylguanidine, triphenylguanidine, diortho Guanidine compounds such as nitrile guanidine, orthonitrile biguanide, diphenylguanidine phthalate; aldehyde amines such as acetaldehyde-aniline reactant, butyraldehyde-aniline condensate, hexamethylenetetramine, acetaldehyde ammonia; and aldehyde-ammonia compounds; 2-mercapto Imidazoline compounds such as imidazoline; thiocarbanilide, diethylthiourea, dibutylthiourea, trimethylthiourea, diorthotolylthiourea and the like; Aurea compounds; thiuram compounds such as tetramethylthiuram monosulfide, tetramethylthiuram disulfide, tetraethylthiuram disulfide, tetrabutylthiuram disulfide, pentamethylenethiuram tetrasulfide; zinc dimethyldithiocarbamate, zinc diethyldithiocarbamate, di-n-butyl Zinc dithiocarbamate, zinc ethylphenyldithiocarbamate, zinc butylphenyldithiocarbamate, sodium dimethyldithiocarbamate,
Dithiocarbamate compounds such as selenium dimethyldithiocarbamate and tellurium dimethyldithiocarbamate;
Xanthate compounds such as zinc dibutylxanthate;
Compounds such as zinc oxide (zinc white) can be given.

In the present invention, the vulcanization accelerator is usually used in an amount of 0.1 to 100 parts by weight of the olefin rubber (A).
It can be used in a proportion of 20 parts by weight, preferably 0.5 to 15 parts by weight, more preferably 1 to 10 parts by weight. The organic peroxide may be any compound that is usually used for peroxide vulcanization of rubber. For example, dicumyl peroxide, di-t-butyl peroxide, di-t-butylperoxy-3,3,5-trimethylcyclohexane, t-
Butyl hydroperoxide, t-butylcumyl peroxide, benzoyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne-
3,2,5-dimethyl-2,5-di (benzoylperoxy) hexane, 2,5-dimethyl-2,5-mono (t
-Butylperoxy) hexane, α, α'-bis (t-
Butylperoxy-m-isopropyl) benzene and the like. Among them, dicumyl peroxide, di-
T-butyl peroxide and di-t-butylperoxy-3,3,5-trimethylcyclohexane are preferably used. These organic peroxides are used alone or in combination of two or more.

In the present invention, the amount of the organic peroxide is usually 0.05 to 100 g per 100 g of the olefin rubber (A).
Although it can be used in a proportion of 2 mol, preferably 0.08 to 1.5 mol, it is desirable to appropriately determine an optimal amount according to required physical properties. When an organic peroxide is used as a vulcanizing agent, it is preferable to use a vulcanizing aid in combination. Specific examples of the vulcanization aid include sulfur; quinone dioxime compounds such as p-quinone dioxime; methacrylate compounds such as polyethylene glycol dimethacrylate; allyl compounds such as diallyl phthalate and triallyl cyanurate; Other maleimide compounds include divinylbenzene. Such a vulcanization aid is usually used in an amount of 0.5 to 1 mol of the organic peroxide used.
２2 mol, preferably about equimolar.

The unvulcanized rubber compound can be prepared, for example, by the following method. That is, the olefin-based rubber (A), the thermoplastic resin (B), the reinforcing agent (C), and other additives, if necessary, are mixed at a temperature of 140 to 180 ° C. for about 3 hours by using a mixer such as a Banbury mixer. After kneading for 10 to 10 minutes, using a roll such as an open roll, a vulcanizing agent, a vulcanization accelerator or a vulcanization aid was additionally mixed and kneaded at a roll temperature of 40 to 80 ° C. for 5 to 30 minutes. Thereafter, the kneaded material is separated to prepare a ribbon-shaped or sheet-shaped unvulcanized rubber compound. The thus-prepared unvulcanized rubber compound is molded into a desired shape using a mold by an extruder, a calender roll, a press, a transfer molding machine, an injection molding machine, etc., and usually 140 to 200
The mixture is heated at a temperature of 1 to 30 minutes to obtain a vulcanized rubber.

[0023]

The present invention will be further described below with reference to Examples and Comparative Examples.
Although specifically described, the scope of the present invention is not limited to these examples.
It is not limited at all. In Examples and Comparative Examples,
The following methods are used to evaluate the properties of vulcanized rubber molded articles, etc.
It is. (1) Tensile test A vulcanized rubber sheet was punched out and JIS K6301 (19
No.3 type dumbbell shape described in (1989)
To obtain a test piece. Using this test piece, JIS K6
301 Measured temperature according to the method specified in Paragraph 3.
Perform a tensile test at 25 ° C and a tensile speed of 500 mm / min.
100% modulus (M₁₀₀), 200% modular
Su (M₂₀₀), 300% modulus (M₃₀₀), Tension
Strength (T _B) And elongation (E_B) Was measured.

(2) Hardness test The hardness test was performed in accordance with JIS K6301 (1989), and the spring hardness H _S (JIS A hardness) was measured. (3) Compression set test The compression set test is based on JIS K6301 (1989)
And the compression set (%) was determined.

(4) Dynamic Viscoelasticity Test The dynamic viscoelasticity test was conducted by Scientific Far
Using RSA-2 manufactured by Gust Co., Ltd. at a measurement temperature of 25 ° C.
Under the conditions of frequency 1 Hz / 100 Hz and distortion rate 0.1%,
Performed on a 1 mm sheet, the complex modulus E^*(× 10⁷
dyne / cm ^Two). In addition, dynamic magnification (in-vehicle noise
Index) and loss tangent (tan δ) (index of ride quality)
Was determined by the following equation. E^*= E '+ iE "(E^*: Complex elastic modulus, E ′: dynamic elastic modulus, E ″: dynamic loss
Dynamic modulus = E at 100 Hz^*/ 1Hz E^* tan δ = E ″ / E ′

(5) Strain dependency test An index (%) obtained by a strain dependency test of a complex elastic modulus E ^* obtained from a dynamic viscoelasticity test of a vulcanized rubber = [E ^* (1%) /
E ^* (0.1%)] × 100. E ^* = E '+ iE "(E': dynamic elastic modulus, E": dynamic loss elastic modulus) RS manufactured by Scientific Far East Co., Ltd.
Using A-2, the measurement was performed under the conditions of a measurement strain range of 0.01 to 2.23%, a measurement temperature of 25 ° C., a frequency of 10 Hz, an initial load of 50 gm, and a sample shape: a strip shape (10 × 1 × 22.4 mm). .

(6) Heat aging resistance test The heat aging resistance test was carried out according to JIS K6301 (1989).
Performed according to. (7) Average particle size of polyolefin resin dispersed particles Electron microscope (trade name: H-8100 (200 KV),
(Manufactured by Hitachi, Ltd.), and the sample prepared in the following manner was measured. <Preparation of Sample> A pellet of the rubber composition (EPDM / thermoplastic resin alloy) was trimmed, a thin film piece having a thickness of 0.1 μm or less was prepared with a microtome, and this thin film piece was dyed with ruthenic acid. Next, carbon was vapor-deposited on the thin film piece to obtain a sample for an electron microscope.

(Examples 1 to 3 and Comparative Example 1) Each rubber compound was prepared at the compounding ratio shown in Table 1, and this was mixed with a BB4 type Banbury mixer (manufactured by Kobe Steel Ltd.).
After kneading at 70 ° C. for 5 minutes and cooling, the obtained kneaded product was mixed with dicumyl peroxide (40% concentration) as a vulcanizing agent in ethylene / α-olefin / non-conjugated polyene copolymer rubber (EPDM) 100 6.8 parts by weight with respect to parts by weight, an 8 inch roll (the temperature of the front roll and the rear roll is 50
C.), kneaded at 170.degree.
After pressing for 2 minutes, a vulcanized sheet having a thickness of 2 mm was obtained, and a physical property test was performed on the vulcanized sheet. Further, a thick vulcanized rubber molded article for a compression set test was obtained by setting the pressing conditions at 170 ° C. for 15 minutes, and a compression set test was performed on the thick vulcanized rubber molded article. Table 1 shows the results. For dynamic viscoelasticity test, 1m at 170 ° C for 15 minutes
m sheets were obtained.

[0029]

[Table 1]

1) Ethylene / propylene / 5-ethylidene-2-norbornene copolymer rubber Ethylene content: 58% by weight, diene content: 8% by weight (ethylene content + propylene content + diene content = 100) Iodine value: 20 135 Intrinsic viscosity [η] measured in decalin at 2.1 ° C: 2.1 dl / g

2) Propylene polymer DSC (melting point): 161 ° C. Average particle size (μm): 0.2 Melt flow rate [ASTM D 1238, 230 ° C., load 2.16 k
g]: 3 g / 10 min. Aspect ratio of dispersed particles: 1.1 Crystallinity: 90%

3) Propylene polymer DSC (melting point): 160 ° C. Average particle size (μm): 0.3 Melt flow rate [ASTM D 1238, 230 ° C., load 2.16 k
g]: 10 g / 10 min. Aspect ratio of dispersed particles: 1.4 Crystallinity: 80%

4) Propylene polymer DSC (melting point): 152 ° C Average particle size (μm): 0.2 Melt flow rate [ASTM D 1238, 230 ° C, load 2.16k
g]: 15 g / 10 min. Aspect ratio of dispersed particles: 1.1 Crystallinity: 60% 5) FEF carbon black (trade name: Niteron # 1)
0, manufactured by Nippon Steel Chemical Co., Ltd.) 6) Paraffin-based process oil (trade name: Diana Process PW-380, manufactured by Idemitsu Kosan Co., Ltd.) 7) Mooney viscosity ML (1 + 4) 100 ° C.

(Examples 4 to 7 and Comparative Example 2) Each rubber compound was prepared at the compounding ratio shown in Table 2, and this was mixed with a BB4 type Banbury mixer (manufactured by Kobe Steel Ltd.).
After kneading at 70 ° C. for 5 minutes and cooling, 0.70 parts by weight of a vulcanization accelerator 2-mercaptobenzothiazole (trade name: Noxeller M, Ouchi Shinko Chemical Co., Ltd.) was added to the obtained kneaded material. Sulfuric accelerator zinc di-n-butyldithiocarbamate (trade name: Suncellar Bz, Sanshin Chemical Industry Co., Ltd.)
2 parts by weight, vulcanization accelerator tetramethylthiuram disulfide (trade name: Suncellar TT, Sanshin Chemical Industry Co., Ltd.)
Add 0.70 parts by weight and 0.75 parts by weight of insoluble sulfur, and add an 8 inch roll (the temperature of the front roll and the rear roll is 50
C.), kneaded at 170.degree.
After pressing for 2 minutes, a vulcanized sheet having a thickness of 2 mm was obtained, and a physical property test was performed on the vulcanized sheet. Further, a thick vulcanized rubber molded article for a compression set test was obtained by setting the pressing conditions at 170 ° C. for 15 minutes, and a compression set test was performed on the thick vulcanized rubber molded article. Table 2 shows the results. The test sheet for viscoelasticity is 1mm at 170 ° C for 5 minutes.
Got something.

[0035]

[Table 2]

1) Ethylene / propylene / 5-ethylidene-2-norbornene copolymer rubber Ethylene content: 58% by weight, diene content: 8% by weight (ethylene content + propylene content + diene content = 100) Iodine value: 21 135 Intrinsic viscosity [η] measured in decalin at ℃: 3.9 dl / g Mooney viscosity ML (1 + 4) 100 ° C: 100 (measured value after oil extension) Oil extension: 50 parts by weight of paraffin oil (rubber 100 weight) Part)

2) Propylene polymer DSC (melting point): 160 ° C. Average particle size (μm): 0.3 Melt flow rate [ASTM D 1238, 230 ° C., load 2.16 k
g]: 10 g / 10 min. Aspect ratio of dispersed particles: 1.5 Crystallinity: 85%

3) FEF carbon black (trade name: Niteron # 10, manufactured by Nippon Steel Chemical Co., Ltd.) 4) Silica (trade name: DUROSIL, manufactured by Degussa) 5) Paraffin-based process oil (trade name: Diana Process PW-380, 6) Mooney viscosity ML (1 + 4) 121 ° C 7) Complex modulus E determined from dynamic viscoelasticity test of vulcanized rubber
^* Index obtained with strain-dependent test ^{(%) = [E * (} 1
%) / E ^* (0.1%)] × 100

[0039]

The rubber composition for heat-resistant and vibration-proof rubber of the present invention comprises:
A vulcanized rubber molded article having excellent properties such as heat resistance and anti-vibration properties and excellent heat aging resistance can be provided.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI // (C08L 23/16 101: 00) (C08L 23/16 23:02)

Claims (6)

[Claims] 1. A thermoplastic resin (B) of 5 to 40 parts by weight and a reinforcing agent (C) of 25 to 70 parts by weight are blended with respect to 100 parts by weight of an olefin rubber (A). A rubber composition for heat-resistant vibration-proof rubber having an A hardness of 30 to 70. 2. An index (%) obtained by a strain dependency test of a complex elastic modulus E ^* obtained from a dynamic viscoelasticity test of a vulcanized rubber =
The value of [E ^* (1%) / E ^* (0.1%)] × 100 is 9
The rubber composition for heat and vibration proof rubber according to claim 1, which is 0% or more. 3. The rubber composition according to claim 1, wherein the reinforcing agent is carbon black and / or silica. 4. An ethylene / α-olefin / non-conjugated polyene copolymer rubber comprising an olefin rubber (A) comprising ethylene, an α-olefin having 3 to 20 carbon atoms and a non-conjugated polyene. 4. The rubber composition for heat-resistant and vibration-proof rubber according to any one of 3. 5. The heat-resisting material according to claim 1, wherein the thermoplastic resin (B) is a crystalline polyolefin resin having a melting point (Tm) measured by DSC in the range of 150 to 200 ° C. Rubber composition for anti-vibration rubber. 6. The crystalline polyolefin resin has an average particle size of 0.1 to 20 μm determined at a level of 10,000 times with an electron microscope.
6. The rubber composition for heat and vibration proof rubber according to claim 5, wherein the rubber composition is dispersed in the range of m.