JP3199374B2 - Crosslinked rubber composition - Google Patents

Description

The present invention relates to a crosslinked rubber composition of a hydrogenated conjugated diene polymer having excellent heat resistance, mechanical strength, weather resistance, ozone resistance and durability. About.

[Prior art] A rubber composition has a low elastic modulus as compared with other materials, is capable of large deformation, has a vibration absorbing performance, has a large frictional resistance, and the like. It is used in various fields to make use of its features.

In recent years, rubber compositions used for automobile parts, electric parts, industrial goods, building materials, etc., have been used in heat resistance, severer use environments, and extended use periods due to factors such as heat resistance,
Improvements in weather resistance, ozone resistance, and durability have been demanded.

Among the various raw material rubber polymers that have been used in the past, natural rubber, polybutadiene rubber, styrene-butadiene rubber, and other rubber compositions mainly containing conjugated diene rubbers have insufficient ozone resistance and heat resistance. Therefore, it is not necessarily suitable for applications that are frequently used outdoors or applications that are exposed to high temperatures for a long time.

On the other hand, ethylene-propylene copolymer rubber (EPM) and ethylene-propylene-polyene copolymer rubber (EPDM) having less unsaturated bonds have better weather resistance, ozone resistance and heat resistance than conjugated diene rubber. Therefore, it has been used for automobile parts, heat-resistant hoses, building materials and the like. However, rubber compositions mainly composed of EPM and EPDM,
The compression set resistance, mechanical strength, heat resistance and the like were not always sufficient.

Under these circumstances, as a polymer for improving the weather resistance and ozone resistance of a conventional conjugated diene polymer, a polymer obtained by hydrogenating an unsaturated double bond of a conjugated diene polymer and a rubber composition thereof are used. JP-B-46-35497, JP-B-47-8928, JP-B-48-30351, JP-A-52
−96695, etc., but the workability, strength,
It is said that the wear resistance is not sufficient. Further, as an improvement of the above hydrogenated polymer, JP-A-60-25
2643, JP-A-62-283105, JP-A-63-4154
No. 7 discloses a hydrogenated polymer of polybutadiene or styrene-butadiene copolymer having a specific structure and a composition thereof. However, the techniques disclosed therein are aimed at improving the processability of rubber compositions and the performance improvement of tire applications such as abrasion resistance, and the ozone resistance of these compositions is based on conventional conjugated diene-based polymers. Although some improvement can be seen as compared with the composition of EPDM, it is inferior to EPDM and the heat resistance is not sufficient.

Further, JP-A-1-185341, JP-A-2-70733, JP-A-2-70734 discloses a hydrogenated conjugated diene-based polymer rubber composition having good weather resistance, Just using the hydrogenated conjugated diene polymer disclosed in these, sufficient strength, weather resistance, ozone resistance,
A rubber composition having heat resistance and compression set resistance cannot be obtained.

[Problems to be Solved by the Invention] The present invention has been made to solve the above-mentioned conventional technical problems, and includes ozone resistance, heat resistance, compression set resistance, mechanical strength, and heat resistance. An object of the present invention is to provide a rubber composition having good properties.

[Means for Solving the Problems] The present inventors have made intensive studies on the polymer structure and the crosslinking method of the hydrogenated conjugated diene-based polymer, and
In order to solve the above problems, it is not enough to simply define the polymer structure of the hydrogenated conjugated diene polymer,
It is necessary to define the crosslinking method, that is, the hydrogenation rate of the hydrogenated conjugated diene-based polymer is extremely high, and it has been found that the above problem can be solved by using a specific crosslinking system. Reached.

That is, the present invention relates to an olefin of a polybutadiene or styrene-butadiene copolymer having a styrene content of 0 to 40% by weight, a butadiene content of 100 to 60% by weight, and a vinyl bond amount of a butadiene portion of 25 to 70%. A hydrogenated conjugated diene-based polymer in which 97 to 100% of unsaturated double bonds are hydrogenated is obtained by mixing (1) a radical-generating compound selected from a peroxide compound and (2) one mole of the radical-generating compound of (1). 0.2 for
Selected from sulfur, N, N'-m-phenylenebismaleimide, p-quinonedioxime, ethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, triallyl cyanurate, triallyl isocyanurate in a mole to 5 mole ratio. A crosslinked rubber composition for a tire tube and a crosslinked rubber composition for an anti-vibration rubber, wherein the crosslinked rubber composition is crosslinked by a combination crosslinking agent system comprising the substance (1) that activates the radical generating compound.

Rubber-like polymer used in the crosslinked rubber composition of the present invention,
A hydrogenated conjugated diene-based polymer in which 97 to 100% of the olefinically unsaturated double bonds of the polybutadiene or styrene-butadiene copolymer having a specific structure are hydrogenated. When the hydrogenation ratio of the olefinically unsaturated double bond is less than 97%, the weather resistance and ozone resistance of the crosslinked rubber composition are inferior. The hydrogenation rate is preferably in the range of 98 to 100%, and 99 to 1%.
A range of 00% is more preferable.

Polybutadiene or styrene before hydrogenation
Butadiene copolymer, in a hydrocarbon solvent, an alkali metal or alkaline earth metal as a polymerization catalyst, alkoxide as a co-catalyst, an organic acid salt, if necessary, further as a vinyl bond amount regulator, ether, polyether, A polar compound such as a tertiary amine is added, and the compound is obtained by an anionic polymerization method in which butadiene is polymerized or styrene and butadiene are copolymerized. In particular, it is preferably obtained by a polymerization method using an organic lithium compound as a polymerization catalyst.

Polybutadiene or styrene before hydrogenation
The styrene content of the butadiene copolymer ranges from 0 to 40% by weight, and the butadiene content ranges from 100 to 60% by weight. If the styrene content exceeds 40% by weight, the rubber elasticity becomes insufficient. The styrene content is more preferably in the range of 0 to 30% by weight to provide good heat resistance, and particularly preferably in the range of 0 to 20% by weight.

In the case of a styrene-butadiene copolymer,
When a random copolymer or a block copolymer and a copolymer obtained by combining them are used, and the crosslinked rubber composition has particularly good rubber elasticity, a so-called block styrene amount (IMKolthoff, J. Polymer Sci. 1, 429
(According to the method of (1946)) is preferably less than 5% by weight of the polymer, while the crosslinked rubber composition having a high hardness contains at least 5% by weight of block styrene. It is preferably a block copolymer. Styrene may be present uniformly in the molecular chain, may increase or decrease along the molecular chain, or may have a form in which random parts having different amounts of styrene are bonded.

Polybutadiene or styrene before hydrogenation
The vinyl bond content of the butadiene portion of the butadiene copolymer is
It is in the range of 25-70%.

When the amount of vinyl bonds in the butadiene portion is reduced, the tendency of the rubbery polymer after hydrogenation to crystallize and exhibit resinous properties is increased. In this case, the tensile strength at room temperature of the crosslinked rubber composition is high and the hardness is also high, but the temperature change of the elastic modulus in the operating temperature range, that is, between 0 and 100 ° C., is not preferable. The vinyl bond amount at which the rubbery polymer hardly crystallizes tends to decrease as the styrene content increases.
On the other hand, when the amount of vinyl bonds in the butadiene portion increases, the mechanical strength decreases and durability becomes a problem, and the low-temperature performance also deteriorates because the glass transition temperature increases.

The vinyl bond amount of the butadiene portion is preferably in the range of 30 to 60%, more preferably 30 to 55% in consideration of the balance between rubber elasticity, low-temperature performance and compression set.

The vinyl bond of the butadiene portion may be present uniformly in the molecule, may increase or decrease along the molecular chain, or may exist in a block shape.

Further, the polymer before hydrogenation may have a linear structure, a branched structure, or a mixed structure thereof. By adopting a branched structure, the processability of the polymer after hydrogenation can be improved, but the extreme branched structure increases the number of free molecular terminals and impairs the heat resistance and mechanical strength of the crosslinked rubber composition. It is not preferable. The polymer having a branched structure is obtained by, in the above-mentioned anionic polymerization method, adding an active terminal of the polymer to a polyfunctional coupling agent, for example,
It is obtained by reacting with silicon tetrachloride, tin tetrachloride, dimethyl adipate, polyepoxy compound and the like.

Also, the weight average molecular weight (Mw) of the polymer before hydrogenation
Is preferably in the range of 1 to 1,000,000, and the molecular weight distribution (Mw / Mn) is preferably in the range of 1.2 to 5.0.

As a process for producing the polymer before hydrogenation, any of a batch process, a continuous process, and a combination thereof can be used.

The hydrogenated polymer of the present invention is obtained by subjecting the conjugated diene-based polymer to a hydrogenation reaction up to a predetermined hydrogenation rate in a hydrocarbon solvent by applying a pressure of 1 to 100 kg / cm ² in the presence of a hydrogenation catalyst. It can be obtained by:

Regarding the method and conditions of the hydrogenation reaction, any methods and conditions can be used as long as a polymer having a high hydrogenation rate as defined in the present invention can be obtained. Examples of the hydrogenation method include a method using a catalyst containing an organometallic compound of titanium as a main component as a hydrogenation catalyst,
Iron, nickel, a method of using a catalyst composed of an organic metal compound such as an alkyl aluminum and an organic compound of cobalt, ruthenium, a method of using an organic complex catalyst of an organic metal compound such as rhodium, palladium, platinum, ruthenium,
There is a method using a catalyst in which a metal such as cobalt or nickel is supported on a carrier such as carbon, silica or alumina. Among the various methods, recently developed organometallic compounds of titanium alone or with lithium, magnesium,
It is industrially preferable to use a homogeneous catalyst comprising an organometallic compound of aluminum (JP-A-59-133203, JP-A-60-220147) and hydrogenation under mild conditions of low pressure and low temperature.

Next, it is cross-linked by a cross-linking system comprising a cross-linking rubber composition radical generator of the invention and a cross-linking aid. The high hydrogenation rate polymer used in the present invention is sufficient for a natural rubber, a conjugated diene polymer such as BR or SBR, or a cross-linking system of a combination of sulfur and a vulcanization accelerator used as a cross-linking agent for EPDM. The crosslink density cannot be obtained. Further, the polymer having a high hydrogenation rate used in the present invention cannot obtain a sufficient crosslinking density even with a crosslinking system using only a radical generator. As shown in the present invention, by combining a radical generator and a specific type of crosslinking aid in a specific ratio range, the polymer having a high hydrogenation rate used in the present invention can obtain a sufficient crosslinking density. As a result, the crosslinked rubber composition exhibits high tensile strength, low compression set, low heat build-up, good heat resistance, good durability, good weather resistance, and ozone resistance.

The radical generator used as the cross-linking agent is a compound that generates a radical by heating, such as a peroxide compound, and is preferably an organic radical generator that has good mixing with the composition of the present invention. Examples thereof include dicumyl peroxide, tert-butyl cumyl peroxide, di-tert-butyl peroxide, 1,1-b
is (tert-butylperoxy) -3,3,5-trimethylcyclohexane, 2,5-dimethyl-2,5-di- (tert-butylperoxy) hexane, 2,5-dimethyl-2,5-di (Te
rt-butylperoxy) hexane-3, α, α'-bis
(Tert-butylperoxy-m-isopropyl) benzene, tert-butylperoxybenzoate, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, 1,1
-Bis (tert-butylperoxy) octane, n-butyl-4,4-bis (tert-butylperoxy) valerate,
Tert-butyl peroxyisopropyl carbonate and the like can be used, and they can be used in combination. The amount of these radical generators, per 100 parts by weight of the polymer,
It is used in the range of 0.002 mol to 0.1 mol. When the amount of the radical generator is less than 0.002 mol, crosslinking is not sufficient, and elasticity and
Tensile strength is inferior, and if it exceeds 0.1 mol, elongation, tensile strength is reduced and durability is inferior. This amount is more preferably in the range of 0.005 mol to 0.05 mol per 100 parts by weight of the polymer.

Next, the compound used as a crosslinking aid is a compound having a function of increasing the crosslinking efficiency of the radical generator. As those compounds, sulfur, N, N'-m-phenylene bismaleimide, p-quinone dioxime, ethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, triallyl cyanurate, triallyl isocyanurate, and the like can be used. They can also be used in combination.

The amount of the cross-linking aid is used in a certain molar ratio to the radical generator, and the amount is used in the range of 0.2 mol to 5 mol per 1 mol of the radical generator. A range from 0.5 mol to 2 mol is preferred.

If the amount of the crosslinking assistant is less than 0.2 mol per mol of the radical generator, sufficient crosslinking cannot be achieved, and if it exceeds 5 mol, the crosslinking density is reduced and the compression set is inferior. The amount of the crosslinking assistant is 0.5 mol to 2 mol per mol of the radical generator.
A molar range is more preferred.

The cross-linked rubber composition of the present invention may further include ethylene-propylene-polyene copolymer rubber (EPDM) and ethylene-propylene rubber as other rubbery polymers as long as the characteristics of the performance of the rubber composition are not lost. (EPM), butyl rubber, acrylic rubber, fluorine rubber, silicon rubber, chlorinated polyethylene, epichlorohydrin rubber, acrylonitrile-butadiene rubber, hydrogenated acrylonitrile-
Butadiene rubber, styrene-butadiene rubber, polybutadiene rubber, polyisopropylene rubber, natural rubber and the like can be added.

Various compounding agents that are usually compounded in the rubber composition can be compounded in the crosslinked rubber composition of the present invention.

These compounding agents include reinforcing agents, fillers, softeners, plasticizers, processing aids, antioxidants, anti-aging agents, anti-scorch agents, UV inhibitors, lubricants, foaming agents, foaming aids, flame retardants,
And antistatic agents and coloring inhibitors.

As a reinforcing agent to be blended in the crosslinked rubber composition of the present invention,
Carbon black SAF, ISAF, HAF, FEF, SRF furnace black and thermal black such as MT, FT, etc., inorganic reinforcing agents such as white carbon, basic calcium carbonate, activated calcium carbonate, high styrene resin, cumarone-indene resin And organic reinforcing agents such as phenol-formaldehyde resin, among which carbon black and inorganic reinforcing agents are preferred. When a reinforcing agent is used, the amount is 5 to 200 parts by weight per 100 parts by weight of the polymer.

Fillers include calcium carbonate, clay, talc,
Zeolite, diatomaceous earth, aluminum sulfate, barium sulfate and the like can be used.

As the softener, paraffin-based process oil, naphthene-based process oil, aromatic (aromatic) -based process oil,
Use paraffin wax, petroleum resin, asphalt, vegetable oil-based softener, sub-classes and the like. In particular, paraffin-based process oils, naphthene-based process oils, and aromatic (aromatic) -based process oils are preferred. When a softening agent is used, the amount is 1 to 200 parts by weight per 100 parts by weight of the polymer.

The amounts of the reinforcing agent and the softening agent are used in consideration of the hardness and the elastic modulus of the obtained crosslinked rubber composition.

As the plasticizer, phthalic acid derivatives, adipic acid derivatives, trimellitic acid derivatives, oleic acid derivatives, stearic acid derivatives, phosphoric acid derivatives and the like can be used.

As the processing aid, fatty acids such as stearic acid, lauric acid, and palmitic acid, and metal salts thereof can be used.

Examples of antioxidants or antioxidants include amine derivatives such as diphenylamine and p-phenylenediamine, quinoline derivatives, hydroquinone derivatives, monophenols, diphenols, thiobisphenols, hindered phenols, and phosphorous acid. Esters and the like can be used.

As the UV inhibitor, lubricant, foaming agent, foaming aid, flame retardant, antistatic agent, colorant, and other rubber compounding agents, known rubber compounding agents are used according to the purpose of use.

The crosslinked rubber composition of the present invention becomes a crosslinked rubber composition through the steps of compounding, kneading, molding and crosslinking by a known method.

The crosslinked rubber composition of the present invention can be used as a known rubber product, and examples thereof include a tire tube, an engine mount, a bush, an anti-vibration rubber such as a stopper, a window frame, a glass run, a sponge, a waterproof sheet, and a roofing. It can be used for various applications such as industrial supplies such as electric wires, packings, heater hoses, radiator hoses, automobile parts, and building materials.

Hereinafter, the present invention will be described specifically with reference to Examples and Comparative Examples, but these do not limit the scope of the present invention.

[Example] Hydrogenated polybutadiene (samples 1 to 5) and hydrogenated styrene-butadiene copolymer (samples 6 to 12) in the range of the polymer structure defined by the present invention shown in Table 1 and the book shown in Table 2 Comparative hydrogenated polybutadiene (samples 13, 14, 17) and comparative hydrogenated styrene-butadiene copolymer (samples 15, 16, 18, 1) which are outside the scope of the invention.
9) Further, an ethylene-propylene copolymer (sample 20) and an ethylene-propylene-polyene copolymer (samples 21 and 22) for comparison shown in Table 3 were prepared.

The hydrogenated polybutadiene and the hydrogenated styrene-butadiene copolymer in Tables 1 and 2 were prepared by polymerizing butadiene or copolymerizing styrene and butadiene in a cyclohexane solvent containing a small amount of tetrahydrofuran using an organolithium catalyst. Subsequently, a sample obtained by hydrogenation using di-p-tolylbis (1-cyclopentadienyl) titanium and n-butyllithium as a hydrogenation catalyst.

The styrene content of the polymer, the vinyl bond content of the butadiene portion, the weight average molecular weight (Mw), the molecular weight distribution (Mw / Mn) and the hydrogenation rate were measured by the following methods.

Styrene content: The polymer before hydrogenation was used as a chloroform solution, and the styrene content was measured by UV absorption at 254 nm by a phenyl group of styrene.

Amount of vinyl bond in butadiene portion: A polymer before hydrogenation was used as a heavy chloroform solution, and an NMR spectrum was measured by FT-NMR (270 megameter, manufactured by JEOL Ltd.).
It was calculated from the integrated intensity ratio of protons (= CH ₂ ) due to 1,2 bonds of m to 5.2 ppm and protons (= CH-) of chemical shifts of 5.2 to 5.8 ppm.

Weight average molecular weight (Mw) and molecular weight distribution (Mw / M
n): The polymer before hydrogenation was converted to a THF (tetrahydrofuran) solution, and GPC (LC-5A manufactured by Shimadzu Corporation, column: polystyrene gel HSG-40, 50, 60 each, detector: differential refractometer) Measure the chromatogram at. The weight average molecular weight (Mw) and number average molecular weight (Mn) in terms of polystyrene were calculated and obtained by a standard method using a calibration curve of the relationship between the molecular weight of the peak of standard polystyrene and the retention flow rate.

Hydrogenation rate: The polymer before hydrogenation and the polymer after hydrogenation were used as a heavy chloroform solution, and FT-NMR (270 mega
JEOL), each NMR spectrum was measured, and the polymer before hydrogenation had a chemical shift of 4.7 ppm to 5.2 ppm.
Proton (= CH ₂ ) by 1,2 bond of and chemical shift 5.2p
Calculate the integrated intensity of proton (= CH-) from pm to 5.8 ppm,
On the other hand, for the polymer after hydrogenation, the chemical shift was 0.6 ppm
Methyl protons by hydrogenated 1,2-bond of ~1.0ppm (-CH _3), the chemical shift 4.7ppm~5.2ppm of hydrogenated non 1,2 protons by coupling (= CH _2), the chemical shift
5.2 ppm to 5.8 ppm of non-hydrogenated protons (= CH
-) The respective integrated intensities were determined, and the hydrogenation rate was calculated.

Example 1 and Comparative Example 1 Sample 1 having a polymer structure in the range limited by the present invention
The rubber composition was kneaded with a B-type Banbury mixer at the evaluation ratio shown in Table 4 to obtain a rubber composition, and crosslinked by various crosslinking systems shown in Table 5. The cross-linking temperature was 160 ° C., a cross-linking curve at 160 ° C. was determined for each cross-linking system using a monsanto rheometer, and the optimum vulcanization time was determined by a standard method to perform cross-linking for a predetermined time.

 Table 5 shows the performance measurement results of these samples.

For comparison, EPDM was used and the performance was similarly measured as a crosslinked composition in the crosslinked system shown in Table 6, and the results are shown in Table 6.

 Each measurement was performed as follows.

(1) Hardness and tensile test: Measured according to JIS-K-6301.

(2) Goodrich heat generation: Measured using a Goodrich heat generation tester according to ASTM-D623-58 at a stroke of 0.225 inch, a load of 55 pounds and a test temperature of 50 ° C, and the temperature of the test hardness after 20 minutes. Measure rise (ΔT).

(3) Durable: Method-B De Metti of ASTM-D430-59
aIn accordance with the method using a bending tester, the number of times until the sample was broken was measured at 23 ° C. with a JIS-3 dumbbell test piece set to 20 mm between the marked lines and repeated 100% elongation.

(4) Heat aging resistance: In accordance with JIS-K-6301, air aging was performed in a gear type aging tester set at 125 ° C, and changes in hardness, tensile strength and elongation were measured.

(5) Compression set: Measured after 70 hours at 125 ° C according to JIS-K-6301.

(6) Ozone resistance: According to JIS-K-6301, the conditions of 40 ° C, 20% elongation, and 1 ppm ozone concentration were observed for the crack generation after 500 hours of ozone exposure. Indicate the number, size and depth of cracks according to JIS.

From the results in Table 5, the crosslinked rubber composition using the peroxide compound of Examples 1-1 to 1-5 and sulfur as a crosslinking system, the peroxide compound of Examples 1-6 to 1-9 and N, N'- m
-Crosslinked rubber composition comprising a crosslinked system with phenylene bismaleimide, triallyl isocyanurate and other specific compounds has sufficient modulus, high tensile strength, low Goodrich heat generation, good durability, good heat aging resistance, Shows low compression set and good ozone resistance.

On the other hand, even when Sample 1 was used, the composition of Comparative Example 1-1 in which the crosslinking system was a peroxide compound alone, and Comparative Example 1-2 in which a combination system with a substance having no function as a co-crosslinking agent was used. The composition of Comparative Example 1-3, which has a cross-linking system of a combination of a general vulcanization accelerator and sulfur, does not have a sufficient cross-linking density, has a low tensile strength, has a high heat generation, and has a high ozone resistance. Poor nature.

Furthermore, the crosslinked rubber composition using the EPDM for comparison shown in Table 6 was inferior in heat generation and durability to the crosslinked rubber composition of the present invention even in Comparative Examples 1-4 of the same crosslink system as in the present invention, Comparative Example 1-5, which is a peroxide compound alone, is inferior in tensile strength and durability, and Comparative Example 1-6, which is a general crosslinking system of sulfur and a vulcanization accelerator, has durability, heat aging resistance, and compression The strain was inferior, and none of the performances were better than those of the crosslinked rubber composition of the present invention of Examples.

Table 4 Evaluation Formulations (Example 1, Comparative Example 1) Polymer 100 parts by weight N330 carbon black 40 parts by weight Paraffin-based process oil ^{* 1} 10 parts by weight Zinc white 5 parts by weight Stearic acid 1 part by weight Crosslinking variable * 1: Idemitsu Kosan Diana Process Oil PW380 Example 2 and Comparative Example 2 A hydrogenated polymer having a polymer structure falling within the scope of the present invention shown in Table 1 and a polymer structure falling outside the range of the present invention shown in Table 2 for comparison. The hydrogenated polymer and the ethylene-propylene copolymer and ethylene-propylene-polyene copolymer shown in Table 3 were used.
With the same composition as in Example 1, a crosslinked rubber composition was obtained in the same manner as in Example 1, and the performance was measured. Table 8 shows the results.
And Table 9 below.

From the results in Tables 8 and 9, the styrene content limited in the present invention, the vinyl bond amount of the butadiene portion, each crosslinked rubber composition of Examples using Samples 1 to 12 in the range of hydrogenation rate, It is evident that the temperature change of the hardness is small, exhibiting sufficient modulus, high tensile strength, low grid-rich heat generation, good durability, good heat aging resistance, low compression set, and good ozone resistance.

On the other hand, the polymer structure is a comparative hydrogenated polymer samples 13 to sample which are not included in the scope of the present invention.
The crosslinked rubber composition of each comparative example using No. 19, and the crosslinked rubber composition using the ethylene-propylene copolymer and the ethylene-propylene-polyene copolymer were obtained by temperature change of hardness, tensile strength, heat generation and durability. , Heat aging resistance, compression set and ozone resistance are inferior in performance.

Table 7 Evaluation Formulations (Example 2, Comparative Example 2) Polymer 100 parts by weight N330 carbon black 40 parts by weight Paraffin-based process oil ^{* 1} 10 parts by weight Zinc white 5 parts by weight Stearic acid 1 part by weight Dicumyl peroxide 2.70 parts by weight Sulfur 0.32 parts by weight * 1: Idemitsu Kosan Diana Process Oil PW380 [Effects of the Invention] As described above, the crosslinked rubber composition according to the present invention is excellent as a crosslinked rubber composition such as good tensile strength, low heat generation, good durability, good heat resistance, and good ozone resistance. It is a rubber composition that is extremely suitable for rubber products such as various industrial products and automobile parts.
It has great industrial significance.

Continuation of front page (58) Field surveyed (Int. Cl. ⁷ , DB name) C08J 3/00-3/28 C08L 1/00-101/16

Claims (2)

(57) [Claims] 1. Polybutadiene or styrene having a styrene content of 0 to 40% by weight, a butadiene content of 100 to 60% by weight, and a vinyl bond content of a butadiene portion of 25 to 70%.
97 of olefinically unsaturated double bond in butadiene copolymer
The hydrogenated conjugated diene-based polymer of which 100% has been hydrogenated is added in an amount of 0.2 to 1 mol of the radical-generating compound selected from the peroxide compound and (2) 1 mol of the radical-generating compound of (1).
Selected from sulfur, N, N'-m-phenylenebismaleimide, p-quinonedioxime, ethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, triallyl cyanurate, triallyl isocyanurate in a mole to 5 mole ratio. A crosslinked rubber composition for a tire tube, which is crosslinked by a combination crosslinking agent system comprising the substance (1) and a substance that activates the radical generating compound. 2. Polybutadiene or styrene having a styrene content of 0 to 40% by weight, a butadiene content of 100 to 60% by weight, and a vinyl bond content of a butadiene portion of 25 to 70%.
97 of olefinically unsaturated double bond in butadiene copolymer
The hydrogenated conjugated diene-based polymer of which 100% has been hydrogenated is added in an amount of 0.2 to 1 mol of the radical-generating compound selected from the peroxide compound and (2) 1 mol of the radical-generating compound of (1).
Selected from sulfur, N, N'-m-phenylenebismaleimide, p-quinonedioxime, ethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, triallyl cyanurate, triallyl isocyanurate in a mole to 5 mole ratio. A crosslinked rubber composition for a vibration-proof rubber, characterized in that it is crosslinked by a combination crosslinking agent system comprising the substance for activating the radical generating compound according to (1).