JPH03200854A - Ethylene-propylene-diene terpolymer rubber, elastomer composition containing the same, and vulcanized rubber obtained from the composition - Google Patents

Abstract

PURPOSE:To provide an excellent resistance to heat, weathering, and dynamic fatigue by dispersing sulfur in advance in a rubber mixture comprising two ethylene-propylene-diene terpolymer rubbers, a high molecular type and a low molecular type. CONSTITUTION:Sulfur is dispersed in advance in a rubber mixture which has a Mooney viscosity ML1+4 (100 deg.C) of 60-120 and comprises: 90-40wt.% high molecular ethylene-propylene-diene terpolymer rubber having an ethylene content of 60-82mol%, an intrinsic viscosity [eta] measured in decalin at 135 deg.C of 3.0-5.0dl/g, and an iodine value of 8-35; and 10-60wt.% low molecular ethylene- propylene-diene terpolymer rubber having an ethylene content of 60-82mol%, an intrinsic viscosity [eta] measured in decalin at 135 deg.C of 0.15-0.8dl/g and an iodine value of 8-35.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to an ethylene-propylene-diene rubber, an elastomer composition, and a vulcanized rubber thereof.

Technical background of the invention Ethylene-propylene-diene rubber (EPDM) is
As a rubber with excellent weather resistance, ozone resistance, and heat aging resistance,
Weather stripping, door glass launch channel,
It is often used in static parts of automobile parts, such as radiator hoses.

On the other hand, most parts that require mechanical strength against dynamic fatigue, such as tires and anti-vibration rubber, are made of NR, SBR, B
Conjugated diene rubbers such as R or blends thereof are used.

By the way, as the performance of automobiles has improved in recent years, it has been desired to improve the heat aging resistance and weather resistance of automobile parts.

However, although EPDM has excellent weather resistance, ozone resistance, and heat aging resistance, it has poor dynamic fatigue resistance, so EPDM cannot be used alone for tires, engine mounts, etc.

By the way, JP-A-53-22551 discloses an ethylene-propylene rubber anti-vibration rubber composition with improved fatigue fracture life that has an intrinsic viscosity [η] of 1.0 or less when measured as a xylene solution at 70°C. 10 to 50% by weight of ethylene-propylene-ethylidene norbornene terpolymer,
90 to 50% by weight of an ethylene-propylene-ethylidene norbornene ternary copolymer having an intrinsic viscosity [η] of 3.0 or more measured in the same manner, and 20 to 80 parts by weight of extension oil per 100 parts by weight of rubber. 5 to 90 parts by weight of carbon black and 0.1 to 2 parts by weight of sulfur based on 100 parts by weight of the rubber component are added to the oil-extended rubber obtained by mixing the above, and if necessary, process oil is added. A vulcanizable anti-vibration rubber composition is disclosed.

However, simply combining a high molecular weight ethylene-propylene-ethylidene norbornene terpolymer and a low molecular weight ethylene-propylene-ethylidene norbornene terpolymer can dramatically improve the dynamic fatigue resistance of existing EPDM. I can't let you.

Furthermore, it has been shown that superior mechanical strength can be imparted by modifying EPDM with sulfur.
References are made to Publication No. 82 and Japanese Patent Publication No. 52-777. However, the inventions disclosed in these publications require the addition of sulfur and a sulfur initiator, and the purpose of this is to use EP, which has excellent co-vulcanization properties with highly unsaturated rubber.
It only stipulates that DM be provided. In addition, the degree of co-vulcanization is determined by the tensile strength (Tb) after blending with unsaturated rubber.
It is evaluated only by On the other hand, whether dynamic fatigue resistance has been imparted can only be evaluated by conducting a fatigue test, and in that sense, these publications do not suggest anything about EPDM, which alone has excellent dynamic fatigue resistance. do not have. The invention disclosed in the above publication is a method for producing a co-vulcanizate of a low unsaturated rubber and a highly unsaturated rubber, comprising:
None of these methods is intended to impart dynamic fatigue resistance to EPDM, but rather to impart heat resistance and ozone resistance while maintaining the excellent dynamic fatigue resistance of conjugated diene rubber.

In addition, as an example where dynamic fatigue resistance is most required, high moony EPDM is used for anti-vibration rubber materials.
This characteristic can be obtained by using ``Rubber Chemistry Technology, Vol. 44, 1971''.
10 month, page +043.

However, the use of high molecular weight EPDM is something that everyone in the industry considers, and the point that requires the most research and development is to improve the physical properties without impairing processability. The processability and high molecular weight of EPDM are contradictory factors, and no means for achieving both of them has been disclosed heretofore.

Therefore, it can withstand use under harsh conditions that require dynamic and mechanical durability, which was previously thought to be possible only with natural rubber and blends of these materials, and has excellent heat resistance and weather resistance. It has been desired to develop an ethylene-propylene-diene rubber, an elastomer composition containing the ethylene-propylene-diene rubber, and a vulcanized rubber thereof, which can impart dynamic fatigue resistance.

Purpose of the Invention The present invention provides a material that can withstand use under severe conditions requiring dynamic and mechanical durability, which was conventionally thought to be possible only with natural rubber or blends thereof, and which has excellent properties. The purpose of the present invention is to provide an ethylene-propylene-diene rubber capable of imparting heat resistance, weather resistance, and dynamic fatigue resistance, an elastomer composition containing the ethylene-propylene-diene rubber, and a vulcanized rubber thereof. There is.

Summary of the invention The ethylene-propylene-diene rubber according to the present invention is
The ethylene content is 60 to 82 mol%, and the intrinsic viscosity [η] measured in decalin at 135°C is 3.0 to 5.0 d.
l! /g and has an iodine value of 8 to 35. High molecular weight ethylene-propylene-diene copolymer rubber (A):
and the ethylene content is 60 to 82 mol%, and the intrinsic viscosity [η] measured in decalin at 135°C is 0.15 to 0.8 d.
l/g and an iodine value of 8 to 35. Low molecular weight ethylene-propylene-diene copolymer rubber (B): 1
Mooney viscosity ML (1
It is characterized in that sulfur is present in a dispersed state in the ethylene-propylene-diene rubber whose temperature (00°C) is within the range of 1+460 to 120.

Moreover, the vulcanizable elastomer composition according to the present invention is
The ethylene content is 60-82 mol%, and the intrinsic viscosity [η1] measured in decalin at 135°C is 3.0-5.0 dl.
/g and has an iodine value of 8 to 35. High molecular weight ethylene-propylene-diene copolymer rubber (A): 90
-40% by weight, and the ethylene content is 60-82 mol%, and the intrinsic viscosity [η] measured in decalin at 135 °C is 0.15-0.8 d.
Low molecular weight ethylene-propylene-diene copolymer rubber (B) having A'/g and an iodine value of 8 to 35:
Mooney viscosity ML (
Ethylene-propylene-diene rubber in which sulfur is present in a dispersed state in an ethylene-propylene-diene rubber whose temperature (100℃) is within the range of 1+4 60 to 120.
It is characterized by containing diene rubber.

Furthermore, the vulcanized rubber according to the present invention is characterized in that it is obtained by vulcanizing the elastomer composition according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION The ethylene-propylene-diene rubber, elastomer composition, and vulcanized rubber thereof according to the present invention will be specifically described below.

The ethylene-propylene-diene rubber according to the present invention is
Specific high molecular weight ethylene-propylene-diene copolymer rubber (A) and specific low molecular weight ethylene-propylene-
Ethylene composed of diene copolymer rubber (B)
Composed of propylene-diene rubber and sulfur.

Ethylene-Propylene-Diene Rubber The high molecular weight ethylene-propylene-diene copolymer rubber (A) used in the present invention consists of ethylene, propylene, and a non-conjugated diene.

Specifically, the above-mentioned non-conjugated dienes include quenched non-conjugated dienes such as 1,4-hexadiene, ethylidenenorbornene (ENB), norbornadiene, methylenenorbornene, dicyclopentadiene, 2-methylnorbornadiene, Examples include cyclic non-conjugated dienes such as 5-vinyl-2-norbornene. Among these, ENB is particularly preferably used.

Further, the high molecular weight ethylene-propylene-diene copolymer rubber (A) used in the present invention has an iodine value of 8 to 35, preferably 10 to 3, which is an index of nonconjugated diene content.
It is 0.

The high molecular weight ethylene-propylene-diene copolymer rubber (A) used in the present invention has an intrinsic viscosity [η] of 2.5 to 5, Od//g, preferably 3.0 as measured in decalin at 135°C. -4.3 dl/g, and the ethylene content is 60-82 mol%. In particular, for applications such as engine mounts that require little change in vibration damping properties from low to high temperatures, it is preferable that the ethylene content be within the range of 60 to 72 mol%. High ethylene type EPD with high mechanical strength
It is preferable that M, that is, the ethylene content, is in the range of 70 to 80 mol%.

The low molecular weight ethylene-propylene-diene copolymer rubber (B) used in the present invention consists of ethylene, propylene, and a non-conjugated diene. This non-conjugated diene is the high molecular weight ethylene-propylene-diene copolymer rubber (A
), and ENB is particularly preferably used.

Further, the iodine value of the low molecular weight ethylene propylene-diene copolymer rubber (B) used in the present invention is also the same as the iodine value of the high molecular weight ethylene-propylene-diene copolymer rubber (A), 8 to 35, Preferably it is 10-30.

In the present invention, the larger the difference in non-conjugated diene content between the high molecular weight ethylene-propylene-diene copolymer rubber (A) and the low molecular weight ethylene-propylene copolymer rubber (B), the larger the difference in iodine value. The iodine value of the low molecular weight ethylene-propylene-diene copolymer rubber (B) is It is preferable to select the iodine number so that it has the same iodine value as the high molecular weight ethylene-propylene-diene copolymer rubber (A).

Furthermore, the low molecular weight ethylene-propylene-diene copolymer rubber (B) used in the present invention has an intrinsic viscosity [η] of 0.15 to 0.8 cl/g as measured in decalin at 135°C.
, preferably 0.2 to 0.4 dl/g, and the ethylene content is 60 to 82 mol%. In particular, for applications such as engine mounts that require little change in vibration damping properties from low to high temperatures, it is preferable that the ethylene content is within the range of 60 to 72 mol%. It is preferable to use high ethylene type EPDM with high mechanical strength, that is, the ethylene content is within the range of 70 to 80 mol%.

When the intrinsic viscosity [η] of the low molecular weight ethylene-propylene-diene copolymer rubber becomes 0.15 dA'/g or less,
Since the properties are the same as those of paraffinic or naphthenic softeners, no improvement in mechanical strength or fatigue life can be expected.

An elastomer composition containing an ethylene-propylene-diene rubber consisting of a high molecular weight ethylene-propylene-diene copolymer rubber (A) and a low-molecular weight ethylene-propylene-diene copolymer rubber (B) as described above. When the product is in an unvulcanized state, the low molecular weight ethylene-propylene-diene copolymer rubber (B) broadens the molecular weight distribution of the ethylene-propylene-diene rubber and also plays the role of a softening agent. The elastomer composition is a high molecular weight ethylene-propylene-diene copolymer rubber (A
) can maintain high strength and excellent dynamic fatigue resistance.

Further, when the elastomer composition is in a vulcanized state, low molecular weight ethylene-propylene-diene copolymer rubber (B
) is involved in vulcanization by itself, so it has the effect of improving rubber strength and increasing dynamic fatigue resistance due to its stress relaxation effect.

Blending ratio In the present invention, the high molecular weight ethylene-propylene-diene copolymer rubber (A) is composed of the high molecular weight ethylene-propylene-diene copolymer rubber (A) and the low-molecular weight ethylene-propylene-diene copolymer rubber (B). ) 90 to 40% by weight, preferably 85 to 60% by weight based on 100% of the total amount of
The low molecular weight ethylene-propylene-diene copolymer rubber (B) is used in an amount of % by weight, and the low molecular weight ethylene-propylene-diene copolymer rubber (B) is
) is used in an amount of 10 to 60% by weight, preferably 15 to 40% by weight, based on 100% by weight of the total amount.

The ethylene-propylene-diene rubber according to the present invention is composed of the above-mentioned high molecular weight ethylene-propylene-diene copolymer rubber (A) and low molecular weight ethylene-propylene-diene copolymer rubber (B). , Mooney viscosity ML (100°C) 1+4 is 60 to 120, preferably 80 to 100.

Mooney viscosity ML (100℃) is 1+ as above
Ethylene-propylene-diene rubber within the range of 4 has good cross-talk properties with a Banbury mixer.

The present inventors conducted a dynamic viscoelastic test (strain rate 10%, temperature 190°C, sample stage: parallel plate, frequency: 1.58
rid/S ~ 5XI02zd/S), the horizontal axis represents the frequency, the vertical axis represents the complex modulus of elasticity G*, and
The frequency corresponding to E6 is set as ω2, and the frequency corresponding to GI=IE5 is set as ω1, and it is defined as ω = ω2/ω1, and the state of the processability and physical properties of EPDM is expressed using the index of ω. Since this index ω affects the side chains, entanglements, composition distribution, and molecular weight distribution of EPDM, the state of processability and physical properties can be expressed well by using this index. Among the ethylene-propylene-diene rubbers according to the present invention, ethylene-propylene-diene rubbers having ω in the range of 50 to 150 are
In particular, it has an excellent balance between wire crosstalk and physical properties. Ethylene-propylene-diene rubber in which ω is in the above range is suitable for use in dynamic applications because it not only has excellent crosstalk properties but also excellent crack growth resistance and heat aging resistance. I can do it.

Sulfur In the present invention, sulfur is present in a dispersed state in the ethylene-propylene-diene rubber.

That is, an ethylene-propylene-diene rubber that is simply a combination of a high molecular weight ethylene-propylene-diene copolymer rubber (A) and a low-molecular weight ethylene-propylene-diene copolymer rubber (B) as described above. (E
Even if PDM) is used, an elastomer composition with excellent dynamic fatigue resistance, which is the object of the present invention, cannot be obtained. However,
The effect of improving the dynamic fatigue resistance of the above-mentioned combination alone can be clearly seen when compared with a high molecular weight ethylene-propylene-diene copolymer rubber coated with an oil film. However, an EP consisting only of the above combinations
The elastomer composition using DM is natural rubber (NR)
Compared to diene rubbers such as, it has significantly poorer dynamic fatigue resistance.

Therefore, the present inventors have conducted extensive research and have developed an ethylene-propylene-diene system consisting of a high molecular weight ethylene-propylene-diene copolymer rubber (A) and a low-molecular weight ethylene-propylene-diene copolymer rubber (B). By first dispersing sulfur in rubber, then adding appropriate amounts of carbon black, softeners, and other fillers and kneading, an elastomer was created that exhibits superior dynamic fatigue resistance that far exceeds conventional wisdom. It has been found that a composition can be obtained.

As a method for dispersing sulfur in the ethylene-propylene-diene rubber, for example, ethylene-propylene-diene in a solution state can be dispersed.
There is a method of adding sulfur to propylene-diene rubber and then removing the solvent, or a method of kneading sulfur into solid ethylene-propylene-diene rubber using a kneader or internal mixer. Further, the temperature at which sulfur is dispersed is preferably in the range of 90 to 160°C, more preferably 110 to 150°C.

In the present invention, sulfur is used in an amount of 0.1 to 5 parts by weight, preferably 0.3 to 3.0 parts by weight, based on 100 parts by weight of the ethylene-propylene-diene rubber.

The elastomer composition according to the present invention contains the ethylene-propylene-diene rubber according to the present invention as described above, and further includes a softener and an inorganic filler used in the production of vulcanized rubber as described below. It may also contain a filler such as a filler.

Production of vulcanized rubber To obtain vulcanized rubber from the elastomer composition according to the present invention, unvulcanized compounded rubber (elastomer composition) is prepared by the method described below in the same way as when vulcanizing general rubber. The compounded rubber is then molded into an intended shape and then vulcanized.

When producing the vulcanized rubber according to the present invention, depending on the intended use of the vulcanized rubber and its performance, in addition to the sulfur-containing ethylene-propylene-diene rubber, softeners,
The type and amount of the filler such as an inorganic filler, the type and amount of the vulcanization accelerator, and the process for producing the vulcanized rubber are selected as appropriate.

As the above-mentioned softener, softeners commonly used for rubber are used, but specifically, process oils, lubricating oils,
Petroleum-based softeners such as paraffin, liquid paraffin, petroleum asphalt, and petrolatum; Coal tar-based softeners such as coal tar and coal tar pitch; Castor oil, linseed oil,
Fatty oil-based softeners such as rapeseed oil and coconut oil; Tall oil; Salt; Synthetic polymer substances such as petroleum resin, atactic polypropylene, coumaron indene resin, etc. are used. Among these, petroleum-based softeners are preferably used, and process oils are particularly preferred.

Moreover, specifically as an inorganic filler, SRF is used.

GPFXFEF, HAFS l5AF, SAF.

Examples include carbon black such as FT and MT, finely divided silicic acid, light calcium carbonate, heavy calcium carbonate, talc, and clay. In the present invention, the inorganic filler is 20 to 150 parts by weight, preferably 30 to 100 parts by weight, and more preferably 40 to 80 parts by weight based on 100 parts by weight of sulfur-free ethylene-propylene-diene rubber. used in amounts of By using the inorganic filler in an amount within the above range, an elastomer composition and a vulcanized rubber having excellent wear resistance and dynamic fatigue resistance can be obtained.

In the present invention, it is preferable to use a vulcanization accelerator in combination. Specifically, the vulcanization accelerator includes N-cyclohexyl-2-benzothiazole-sulfenamide, N-oxydiethylene-2-benzothiazole-sulfenamide, N,N
-diisopropyl-2-benzothiazole-sulfenamide, 2-mercaptobenzothiazole, 2-(2,
4-dinitrophenyl) mercaptobenzothiazole,
Thiazole compounds such as 2-(26-danityl-4-morpholinothio)benzothiazole and dibenzothiazyl-disulfide; diphenylguanidine, triphenylguanidine, diorthotolylguanidine, orthotolyl.
Guanidine compounds such as bi-guanide and diphenylguanidine phthalate; aldehyde-amines or aldehyde-ammonia compounds such as acetaldehyde-aniline reaction products, butyraldehyde-aniline condensates, hexamethylenetetramine, acetaldehyde-ammonia reaction products; 2- Imidacillin compounds such as mercaptoimidacillin; thiourea compounds such as thiocarbamic acid, diethylthiourea, dibutylthiourea, trimethylthiourea, diorthotolylthiourea; tetramethylthiuram monosulfide, tetramethylthiuram disulfide, tetraethylthiuram Thiuram compounds such as disulfide, tetrabutylthiuram disulfide, pentamethylenethiuram tetrasulfide; zinc dimethyldithiocarbamate, zinc diethyldithiocarbamate, zinc di-n-butyldithiocarbamate, zinc ethylphenyldithiocarbamate, zinc butylphenyldithiocarbamate , dithioate salt compounds such as sodium dimethyldithiocarbamate, selenium dimethyldithiocarbamate, and tellurium diethyldithiocarbamate; xanthate compounds such as zinc dibutylxanthate; and other compounds such as zinc white.

The vulcanization accelerator is 0.1 parts by weight per 100 parts by weight of sulfur-free ethylene-propylene-diene rubber.
~20 parts by weight, preferably 0. It is used in a proportion of 2 to 10 parts by weight.

The unvulcanized compounded rubber is prepared by the following method. In other words, using a mixer such as a Banbury mixer,
Fillers such as the ethylene-propylene-diene rubber, softener, and inorganic filler according to the present invention are kneaded at a temperature of 80 to 170°C for 3 to 10 minutes, and then, using rolls such as open rolls, A vulcanization accelerator is additionally mixed according to the conditions, and after kneading for 5 to 30 minutes at a roll temperature of 40 to 80°C, the mixed wire material is extruded to prepare a ribbon-shaped or sheet-shaped compounded rubber.

The compounded rubber thus prepared is molded into the desired shape using an extruder, calendar roll, or press, and simultaneously with the molding or the molded product is introduced into a vulcanization tank.
It is heated at a temperature of 50 to 270°C for 1 to 30 minutes to form a vulcanized rubber. When performing such vulcanization, a mold may or may not be used. When a mold is not used, the molding and vulcanization steps are usually carried out continuously.

As a heating method in the vulcanization tank, hot air, glass beads fluidized bed, UHF (ultra high frequency electromagnetic waves), steam, etc. can be used.

Effects of the invention The ethylene-propylene-diene rubber according to the present invention is
It contains a specific high molecular weight ethylene-propylene-diene copolymer rubber (A) and a specific low molecular weight ethylene-propylene-diene copolymer rubber (B) in a specific ratio, and has a Mooney viscosity M L r + 4 (100 ℃) is 60~
Because a certain amount of sulfur exists in a dispersed state in ethylene-propylene-diene rubber within the range of It has the effect of being able to withstand use under severe conditions where mechanical durability is required, as well as providing excellent heat resistance, weather resistance, and dynamic fatigue resistance. Among the ethylene-propylene-diene rubbers according to the present invention,
Certain ethylene-propylene-diene rubbers with ω in the range of 50 to 150 are particularly effective.

Furthermore, since the elastomer composition according to the present invention contains an ethylene-propylene-diene rubber that has the above-mentioned effects, it has conventionally been thought that it would be possible to use only natural rubber or a blend thereof. It has the effect of being able to withstand use under harsh conditions that require dynamic and mechanical durability, and has excellent heat resistance, weather resistance, and dynamic fatigue resistance, and also has the effects mentioned above. Vulcanized rubber can be provided.

Furthermore, the vulcanized rubber according to the present invention has a tensile strength (TB),
Since there is almost no variation in tensile elongation (EB) and there is also little variation in fatigue test results, it also has the effect of stabilizing the quality required when manufacturing actual products.

Since the vulcanized rubber obtained from the elastomer composition according to the present invention has the above-mentioned effects, it is widely used in applications such as tires, automobile parts, general industrial parts, and civil engineering and construction materials. In particular, muffler hangers, belts, anti-vibration rubber, engine mounts, pneumatic tire treads, pneumatic tire sidewalls, and white rubber, which have traditionally been thought to be compatible only with diene rubber, especially natural rubber, or blends thereof. It can be suitably used for side walls and the like.

EXAMPLES The present invention will be explained below with reference to Examples, but the present invention is not limited to these Examples.

In addition, the evaluation test method of the vulcanized sheet in Examples and Comparative Examples is as follows.

(1) Tensile test A vulcanized rubber sheet was punched out to obtain a three-bone dumbbell test piece as described in Its K 63G+, and the test piece was measured according to the method specified in Section 3 of JIS K 6301. A tensile test was conducted at a temperature of 25° C. and a tensile speed of 500 mm/min, and the tensile stress at break TB and tensile elongation at break EB were measured.

(2) Heat aging resistance Heat aging resistance is as specified in 6. of JIS K 6301-1975.
5, evaluation is made based on the following retention rate of stress at break, retention rate of elongation at break, and change in JIS^ hardness.

(i) Punch out a JIS K 6301 dumbbell type tensile test piece from the longitudinal direction of the sheet, and
After leaving it at 0℃ for 72 hours, return it to room temperature and cut it to 200mm/
The tensile test was carried out at a speed of
ged) and elongation at break (E Baged). On the other hand, the stress at break (T Bo
rig) and elongation at break (E Borig) are measured in advance, and the retention rate of stress at break and the retention rate of elongation at break are calculated.

Retention rate of stress at break [%] = (T Baged/T Borig) x 100 Retention rate of elongation at break [%] = (E Baged/E Borig) X I Q Q
(i) Change in IISA hardness (Its K 6301) A
H=H2-H.

Here, AII indicates the change in JIS^ hardness, H1 indicates the hardness before vulcanization, and H2 indicates the hardness after vulcanization.

(3) Crack growth properties due to bending (bending test) Crack growth properties due to bending were measured using a dematcher type tester (rotation speed 300 tpm) in accordance with ASTM 08H, and tested three samples of vulcanized rubber at a measurement temperature of 40°C. Bending was repeated until the sheet was cut, and evaluation was made based on the average number of bending times during cutting.

(4) Durability test (Monsanto fatigue test) A vulcanized rubber sheet was punched out to obtain three-bone dumbbell test pieces as specified in JIS K 6301, and each of the 20 test pieces was measured with an elongation rate of 200%. The specimen was subjected to elongation fatigue at a temperature of 40° C. and a rotational speed of 300 rpm, and the average value of the number of times the dumbbell was cut was used as an index of durability.

(5) Heat generation test According to ASTM D 623,
d+1cb) flexometer (IIexomele
+), a heat generation test was conducted under the conditions of a load of 151b and a stroke of 6.9 mm, and the temperature rise (temperature change) was T2-T.
, = Δt was measured. The number of test pieces used for measurement was 2.
The starting temperature of the experiment was 37°C.

Example 1 High molecular weight ethylene-propylene-5-ethylidene-2-norbornene copolymer rubber with an ethylene content of 70 mol%, an intrinsic viscosity [η] of 3.6 dl/g measured in decalin at 135° C., and an iodine value of 20. 70 weight % and ethylene content 70 mol%, intrinsic viscosity measured in decalin at 135°C [
η] 0.24 dl 1 g 1 Consisting of 30% by weight of low molecular weight ethylene-propylene-5-ethylidene-2-norbornene copolymer rubber with an iodine value of 20, Mooney viscosity MLl
+4 (100°C) 82, ω 80 ethylene-propylene diene rubber (hereinafter abbreviated as EPDM-1) 100
1 part by weight and 0.75 part by weight of sulfur using a kneader.
The mixture was kneaded at 30° C. for 3 minutes while applying heat and adding shear to disperse the sulfur.

Next, 1 part by weight of stearic acid and 5 parts by weight of zinc white No.
FEF-HS Carbon [manufactured by Nippon Steel Chemical Co., Ltd., Near 0F11
0160 parts by weight, oil [manufactured by Fuji Kosan ■, P-300
] 10 parts by weight and capacity 4.31! banbury mixer
(manufactured by Kobe Steel, Ltd.).

The thus obtained mixed material was coated with 1.5 parts by weight of a vulcanization accelerator on a 14-inch roll, 1.5 parts by weight of Tsukusela M (trade name, manufactured by Iruuchi Shinko Chemical Industry ■), and 1.5 parts by weight of Tsukusela DM (trade name, manufactured by Iruuchi Shinko Chemical Industry ■). Add 1.5 parts by weight and 0.5 parts by weight of the product name Tsukusela TT [manufactured by Iriuchi Shinko Chemical Industry ■],
The mixing time on the rolls was 4 minutes, the surface temperature of the oven rolls was 50°C on the front roll and 60°C on the back roll, and the rotation speed was 15 rpm for the front roll and 18 rpta for the back roll.
After kneading under the following conditions, it was divided into sheets and heated at 150℃ for 3
Pressing was carried out for 0 minutes to obtain a 2 mm thick vulcanized sheet, and this vulcanized sheet was subjected to a tensile test, a heat aging test, a bending test, a durability test and a heat generation test.

The results are shown in Table 1.

Comparative Example 1 Natural rubber (NR) [RSS No. 1 170 parts by weight,
30 parts by weight of styrene-butadiene rubber (SBR) [manufactured by Asahi Kasei Corporation, trade name: Tuffden+530], 1 part by weight of stearic acid, 5 parts by weight of zinc white No. 1, FEF-HS
50 parts by weight of carbon [Niteron 110, manufactured by Nippon Steel Chemical Co., Ltd.] and 40 parts by weight of oil [P-300, manufactured by Fuji Kosan Corporation] were kneaded in a Banbury mixer (manufactured by Kobe Steel, Ltd.) with a capacity of 4.31.

To the thus obtained mixed material, 1 part by weight of sulfur and a vulcanization accelerator [manufactured by Iruuchi Shinko Kagaku Kogyo ■, Tsukusela-C2] were added.
After adding 3 parts by weight and kneading with a roll, the mixture was cut into sheets and pressed at 150° C. for 30 minutes to obtain a vulcanized sheet with a thickness of 2N, and this vulcanized sheet was evaluated.

The results are shown in Table 1.

Comparative Example 2 1100 parts by weight of EPDM-1 of Example 1, 1 part by weight of stearic acid, 5 parts by weight of Zinc White No. 1, 150 parts by weight of FEF-HS carbon [manufactured by Nippon Steel Chemical Co., Ltd., Nearon 110], and 150 parts by weight of oil [Fuji Kosan Co., Ltd.] P-300] 10 parts by weight and a Banbury mixer with a capacity of 4.31 (manufactured by Kobe Steel, Ltd.)
It was kneaded with

To the thus obtained mixed material, 0.75 parts by weight of sulfur and 1.5 parts by weight of sulfur as a vulcanization accelerator (manufactured by Iriuchi Shinko Kagaku Kogyo ■) and 1.5 parts by weight of Tsukusela DM (trade name) were added to the mixed material thus obtained. Add 1.5 parts by weight of [manufactured by Anauchi Shinko Kagaku Kogyo ■] and 0.5 parts by weight of the product name Tsukusela TT [manufactured by Iriuchi Shinko Kagaku Kogyo ■] and mix on a roll for 4 minutes until the surface temperature of the open roll reaches After kneading at 50°C for the rolls, 60°C for the rear rolls, and 16+pm for the front rolls and 18+pm for the rear full rolls, it was divided into sheets and pressed at 150°C for 30 minutes to a thickness of 2 km. A vulcanized sheet was obtained, and this vulcanized sheet was evaluated.

The results are shown in Table 1.

Comparative Example 3 In Comparative Example 2, high molecular weight ethylene-propylene-5-ethylidene-2-norbornene copolymer rubber (
A vulcanized sheet with a thickness of 2M was obtained in the same manner as in Comparative Example 2, except that the blended amount of myoyl was 60 parts by weight. This vulcanized sheet was evaluated.

The results are shown in Table 1.

Comparative Example 4 High molecular weight ethylene-propylene-5-ethylidene-2-norbornene copolymer rubber with an ethylene content of 70 mol%, an intrinsic viscosity [η] of 2.5 dl/g measured in decalin at 135°C, and an iodine value of 20, 70 weight % and ethylene content 70 mol%, intrinsic viscosity measured in decalin at 135°C [
η] 0.3 dl/g.

Using a nider, 100 parts by weight of ethylene-propylene-diene rubber consisting of 30% by weight of low molecular weight ethylene-propylene-5ethylidene-2-norbornene copolymer rubber with an iodine value of 20 and 2.0 parts by weight of sulfur were mixed at 130% by weight using a nider. °C, 3
The mixture was kneaded with heat and shear for 1 minute to disperse the sulfur.

Next, 1 part by weight of stearic acid and 5 parts by weight of zinc white No. 1 were added to the ethylene-propylene rubber in which sulfur was dispersed.
FEF-HS carbon [manufactured by Asahi Carbon ■, 6011G]
60 parts by weight, oil [manufactured by Fuji Kosan, P-3001]
60 parts by weight were kneaded in a Banbury mixer with a capacity of 4.31 [Kobe Steel, Ltd. type].

To the thus obtained kneaded product, 0.5 parts by weight of the vulcanization accelerator, Tsukusela M [manufactured by Iruuchi Shinko Kagaku Kogyo ■] and 0.5 parts by weight of Tsukusela TT [manufactured by Iruuchi Shinko Kagaku Kogyo ■] and 0.5 parts by weight of the vulcanization accelerator were added to the kneaded material obtained in this way. 1.5 parts by weight was added, the mixing time on the rolls was 4 minutes, the surface temperature of the open roll was 50°C on the front roll, 60°C on the back roll, and the rotation speed was 16+pm on the front roll and 18+pm on the back roll. After kneading under the following conditions, it was divided into sheets and pressed at 150°C for 20 minutes to obtain a 2M thick vulcanized sheet.This vulcanized sheet was subjected to a tensile test, hardness test (Its A hardness), durability test, and heat generation. I conducted a test.

In addition, each of the above-mentioned mixtures was put into a pressurized Nigu (manufactured by Toshin Sangyo Co., Ltd., Model TDI-5) and mixed under steam heating, and the resulting mixture was poured into a front roll (roll: spring type). The mixture was wound around a 8"φ x 20"L steam-heated, water-cooled, automatic temperature control type (manufactured by Seisakusho Co., Ltd.), turned back and forth four times on the left and right sides, and after 1 minute, the roll processability of this mixture was evaluated. Note that the distance between the front roll and the rear roll is 0.6M.

[How to display roll workability] E: Excellent G: Good F: Fair (Fa i +) P: Poor VP: Very poor (VeB Poor) [Display standards] 1) Evaluate the kneaded material wound around the roll after the first turning.

Lower limit of E: There are no holes from the beginning.

Lower limit of G...within about 10 small holes of 2 to 5 holes,
There are no more than several holes around 10 mmφ.

Lower limit of F...The part connected on the roll surface is 50%
That's all.

Lower limit of P: Most of the kneaded material hangs down, and only a portion is wrapped around the roll.

Upper limit of VP...The kneaded material will come off the roll unless you touch it.

2) Evaluate the mixed wire wound around the roll after each of the 2.3.4th turns.

Lower limit of E: No tendency for bagging is observed.

There is perfect adhesion.

Lower limit of G: Although the kneaded material apparently adheres closely to the roll and does not separate from it, it partially waves at the upper part of the roll.

If bagging occurs due to a slip, etc. Even if you do, it will recover with its own blade, but it will recover once with human power. It will be restored with the correction.

Lower limit of F: On the outer peripheral surface of the lower half of the front roll,
Although the kneaded material is in close contact with each other, the adhesion of the mixed material is poor in the range where it passes through this outer peripheral surface and reaches the upper part of the roll, and some parts are wavy.

Lower limit of P: This may cause bagging, but by making corrections from time to time, it is possible to prevent the kneaded material from hanging down from the roll.

Upper limit of VP...Bagging will occur, and if not constantly corrected, the crosstalk will hang from the roll.

The above results are shown in Table 2.

Examples 2 and 3 In Comparative Example 4, instead of the high molecular weight ethylene-propylene-5-ethylidene-2-norbornene copolymer rubber of Comparative Example 4, the intrinsic viscosity measured in decalin at 135° C. with an ethylene content of 70 mol% was used. [η] 3.0 dl/g, high molecular weight ethylene-propylene-5-ethylidene-2-norbornene copolymer rubber with an iodine value of 20, ethylene content 70 mol%, 1
Intrinsic viscosity measured in decalin at 35°C [η] 4.6d
l/g, high molecular weight ethylene-propylene-5-ethylidene-2-norbornene copolymer rubber with an iodine value of 20 was used in Examples 2 and 3, respectively, in the same manner as in Comparative Example 4. A vulcanized sheet with a thickness of 2 mm was obtained, and this vulcanized sheet was evaluated.

The results are shown in Table 2.

Comparative Example 5 In Comparative Example 4, instead of the high molecular weight ethylene-propylene-5-ethylidene-2-norbornene copolymer rubber of Comparative Example 4, the intrinsic viscosity [η] measured in decalin with an ethylene content of 70 mol% and 135°C ] 5.2 dll/g, high molecular weight ethylene-propylene-5-ethylidene-2- with an iodine value of 20
A vulcanized sheet with a thickness of 2 mm was obtained in the same manner as in Comparative Example 4, except that the norbornene copolymer rubber was used, and this vulcanized sheet was evaluated.

The results are shown in Table 2.

Comparative Examples 6 and 7 In Comparative Example 4, instead of the high molecular weight ethylene-propylene-5-ethylidene-2-norbornene copolymer rubber of Comparative Example 4, ethylene content of 70 mol%, intrinsic viscosity measured in decalin at 135 ° C. [η] A high molecular weight ethylene-propylene-5-ethylidene-2-norbornene copolymer rubber of 4.6 dl/g and an iodine value of 20 was used, and the low-molecular weight ethylene-propylene-5-ethylidene-2-norbornene copolymer rubber of Comparative Example 4 was used. Instead of the copolymer rubber, the ethylene content was 70 mol%, the intrinsic viscosity [η] measured in decalin at 135°C was 0.10 dA'/g, and the iodine value was 20.
Low molecular weight ethylene-propylene-5ethylidene-2-
Norbornene copolymer rubber, ethylene content 70 mol%,
Intrinsic viscosity measured in decalin at 135°C [η] 1.0
dl/g, and an iodine value of 20, were used in Comparative Examples 6 and 7, respectively. A vulcanized sheet with a diameter of 2+am was obtained, and this vulcanized sheet was evaluated.

The results are shown in Table 2.

Claims (1)

[Scope of Claims] (1) Ethylene content is 60 to 82 mol%, and 135
The intrinsic viscosity [η] measured in decalin is 3.0 to 5.
High molecular weight ethylene-propylene-diene copolymer rubber (A) which is 0 dl/g and has an iodine value of 8 to 35
:90 to 40% by weight, and the ethylene content is 60 to 82 mol%, and the intrinsic viscosity [η] measured in decalin at 135°C is 0.1.
5 to 0.8 dl/g and an iodine value of 8 to 35. Low molecular weight ethylene-propylene-diene copolymer rubber (B): 10 to 60% by weight, Mooney viscosity M
An ethylene-propylene-diene rubber characterized in that sulfur is present in a dispersed state in the ethylene-propylene-diene rubber having L_1_+_4 (100°C) in the range of 60 to 120. (2) ω_r (ω_
2/ω_1) is within the range of 50 to 150, the ethylene-propylene-diene rubber according to claim 1. (3) Ethylene content is 60 to 82 mol%, and 135
The intrinsic viscosity [η] measured in decalin is 3.0 to 5.
High molecular weight ethylene-propylene-diene copolymer rubber (A) which is 0 dl/g and has an iodine value of 8 to 35
:90 to 40% by weight, and the ethylene content is 60 to 82 mol%, and the intrinsic viscosity [η] measured in decalin at 135°C is 0.1.
5 to 0.8 dl/g and an iodine value of 8 to 35. Low molecular weight ethylene-propylene-diene copolymer rubber (B): 10 to 60% by weight, Mooney viscosity M
Ethylene-propylene-diene rubber in which sulfur is present in a dispersed state in ethylene-propylene-diene rubber whose L_1_+_4 (100°C) is within the range of 60 to 120.
A vulcanizable elastomer composition comprising a diene rubber. (4) ω_r, an index of processability and physical properties of ethylene-propylene-diene rubber determined by dynamic viscoelasticity test
The elastomer composition according to claim 3, wherein (ω_2/ω_1) is within the range of 50 to 150. (5) A vulcanized rubber obtained by vulcanizing the elastomer composition according to claim 3.