JP2002020537A - Rubber composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rubber composition capable of producing vulcanized rubber having abrasion resistance. SOLUTION: This rubber composition comprises 100 pts.wt. one or more kinds of rubbers selected from natural rubbers and synthetic rubbers, 5-250 pts.wt. one or more kinds of filler selected from carbon black and silica and 0.1-10 pts.wt. one or more kinds of sulfur compounds selected from a compound of the following chemical formula (1), a compound of the chemical formula S (CH2CH2COOR2)2 (2) and a compound of the chemical formula C (CH2 OCOCH2CH2SR3)4 (3) (wherein R1, R2 and R3 are each an alkyl group represented by CaH2a+1 (a is an integer selected from 1 to 24).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a rubber composition, and more particularly to a rubber composition having excellent abrasion resistance. The rubber composition of the present invention is suitably used for producing tire treads, milling rolls, rubber rollers, belts, shoe soles, sealing materials, and the like.

[0002]

2. Description of the Related Art In recent years, as resource saving and environmental measures have been emphasized, the demand for abrasion resistance of rubber products has become increasingly severe. In particular, rubber products such as tire treads, milling rolls, rubber rollers, belts, shoe soles, and sealing materials are used while being in dynamic contact with other articles, so their wear resistance makes rubber products usable. Affects duration directly. For this reason, research and development have been continued in search of a rubber composition capable of producing a rubber product having lower abrasion.

As a method of improving the abrasion resistance, there is an improvement in a polymer structure. For example, it is known to add functionalities or blend high molecular weight components, sharpen the molecular weight distribution, or blend a coupling agent that reacts with a filler such as silica. Specifically, for the purpose of improving abrasion resistance, a rubber composition containing a specific carbon black (Japanese Unexamined Patent Application Publication No.
-60985, 11-60800), a rubber composition containing silica having a functional group (JP-A-11-302450), a rubber composition containing a silane coupling agent (JP-A-7-304906),
There is a rubber composition containing a specific zinc salt or sodium thiosulfate (JP-A-9-151279). These have problems such as the need to remodel existing manufacturing equipment and poor balance between the effect of improving abrasion and the cost. Therefore, a method that is low in cost and has a high effect of improving abrasion is desired.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide an abrasion-resistant rubber product using a general-purpose rubber, for example, a rubber product such as a tire tread, a milling roll, a rubber roller, a belt, a shoe sole, and a sealing material. An object is to provide a vulcanizable rubber composition suitable for production.

[0005]

Means for Solving the Problems In order to solve the above-mentioned problems, the present inventors have studied the improvement of abrasion resistance using various additives in a rubber composition for vulcanization. Reached. That is, the present invention relates to 100 parts by weight of one or more rubbers selected from natural rubbers and synthetic rubbers, and one or more fillers 5 to 2 selected from carbon black and silica.
50 parts by weight and one or more sulfur compounds 0.1 to 10 selected from the following chemical formulas (1), (2) and (3)
Provided is a wear-resistant rubber composition characterized by containing parts by weight.

[0006]

Embedded image

S (CH ₂ CH ₂ COOR ² ) ₂ (2) C (CH ₂ OCOCH ₂ CH ₂ SR ³ ) ₄ (3) In the above formula, R ¹ , R ² and R ³ are all _Ca. H
An alkyl group represented by _{2a + 1} (a is an integer selected from 1 to 24);

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
The rubber used in the present invention is selected from natural rubber (NR) and synthetic rubber. Examples of the synthetic rubber include styrene-butadiene copolymer rubber (SBR), acrylonitrile-styrene-butadiene copolymer rubber (NSBR), and polybutadiene. Rubber (BR), polyisoprene rubber (I
R), acrylonitrile-butadiene copolymer rubber (NB
R), ethylene-α-olefin copolymer rubber (EP
M), ethylene-α-olefin-diene copolymer rubber (EPDM), 1,2-polybutadiene rubber (1,2-
PBD).

[0009] Among them, for manufacturing tire tread,
Styrene-butadiene copolymer rubber (SBR), acrylonitrile-styrene-butadiene copolymer rubber (NSB
R), polybutadiene rubber (BR), polyisoprene rubber (IR) and natural rubber, and acrylonitrile-butadiene copolymer rubber (NBR) for milling rolls,
Acrylonitrile-butadiene copolymer rubber (NBR) and styrene-butadiene copolymer rubber (SBR) are used for rubber rollers, and acrylonitrile-butadiene copolymer rubber (NBR) and ethylene-α-olefin copolymer rubber (for belts). EPM), ethylene-α-olefin-
Diene copolymer rubber (EPDM) is 1,2 for shoe sole
-Polybutadiene rubber (1,2-PBD) is preferably used.

[0010] The carbon black used in the present invention is not particularly limited. Examples thereof include furnace black, acetylene black, thermal black, channel black, and the like.
Graphite or the like can be used. Among these, furnace black is particularly preferable, and specific examples thereof include SAF, ISAF, IISAF, HAF, and FE.
Various grades such as F, GPF, APF, SRF, MPF and the like can be mentioned. These carbon blacks can be used alone or in combination of two or more. Although the nitrogen adsorption specific surface area (N ₂ SA) of carbon black is not particularly limited, it is usually 5 to 20.
0 m ² / g, preferably in the range of 50 to 150 m ² / g, more preferably 80~130m ² / g. The DBP oil absorption of carbon black is not particularly limited, but is usually 5 to 300 ml / 100 g, preferably 50 to 200 ml.
ml / 100 g, more preferably 80-160 ml / 1
The range is 00 g.

The silica used in the present invention is not particularly limited, and examples thereof include dry-process white carbon, wet-process white carbon, colloidal silica, and precipitated silica. Among these, wet-process white carbon mainly containing hydrous silicic acid is particularly preferred. Although the specific surface area of silica is not particularly limited, the specific surface area of nitrogen adsorption (B
ET method), usually 50 to 400 m ² / g, preferably 1 to 400 m ² / g.
When it is in the range of 00 to 250 m ² / g, the tensile strength,
And excellent workability. Nitrogen adsorption specific surface area is AS
It is a value measured by the BET method according to TM D3037-81. These silicas can be used alone or in combination of two or more.

One or more fillers selected from carbon black and silica used in the present invention are 5 to 250 parts by weight, preferably 10 to 250 parts by weight, per 100 parts by weight of rubber.
It is 150 parts by weight. If the amount is less than 5 parts by weight, the mechanical strength of the vulcanized rubber will be insufficient, and if it exceeds 250 parts by weight, the elongation of the vulcanized rubber will be insufficient. When silica and carbon black are used in combination, the mixing ratio is appropriately selected depending on the purpose and application, but silica: carbon black (weight ratio)
Is usually 10:90 to 99: 1, preferably 40:60
９０90: 10.

The sulfur compound used in the present invention is represented by the following chemical formula.

[0014]

Embedded image

S (CH ₂ CH ₂ COOR ² ) ₂ (2) C (CH ₂ OCOCH ₂ CH ₂ SR ³ ) ₄ (3) In the above formula, R ¹ , R ² and R ³ are all _Ca. An alkyl group represented by H2a _{+ 1} , wherein a is an integer selected from 1 to 24, and a is preferably selected from 8 to 20, and particularly preferably selected from 12, 14, 16, and 18.

As a specific example of the chemical formula (1), R ¹ is C
_There is a compound consisting of a mixture of compounds of ₁₂ H ₂₅ and C ₁₄ H ₂₉ (Adeka Stub AO-23; manufactured by Adeka Argus Chemical Co., Ltd.). As a specific example of the chemical formula (2), R
3,3′-thiobispropionic acid dilauryl ester wherein ² is C ₁₂ H ₂₅ (Antiox L; NOF Corporation)
Ltd., IRGANOX PS800; manufactured by Ciba-Geigy), R ² is a C ₁₄ H ₂₉ 3,3'-thio-bis acid dimyristyl ester (DMTP "Yoshitomi";
Yoshitomi Pharmaceutical Co., Ltd.), 3,3′-thiobispropionic acid distearyl ester in which R ² is C ₁₈ H ₃₇ (Antiox S; Nippon Yushi Co., Ltd., IRGANOX PS80
2; Ciba-Geigy). Specific examples of the chemical formula (3) include a compound in which R ³ is C ₁₂ H ₂₅ (Adeka Stub AO-412S; manufactured by Adeka Argus Chemical Co., Ltd.). The sulfur compound used in the present invention is 0.1 to 10 parts by weight, preferably 0.3 to 10 parts by weight, based on 100 parts by weight of rubber.
5 parts by weight, more preferably 0.5 to 2 parts by weight. If the amount is less than 0.1 part by weight, the effect of reducing the wear property is insufficient, and if it exceeds 10 parts by weight, the effect on cost becomes insufficient.

The rubber composition of the present invention essentially requires a filler composed of carbon black and / or silica and a specific sulfur compound with respect to the rubber component. Other compounding agents such as sulfurizing agents, vulcanization accelerators, vulcanization accelerators, antioxidants, silane coupling agents, plasticizers, lubricants, fillers other than carbon black and silica, and ethylene-α-olefins In the case of a composition of a system rubber, organic peroxides, polyfunctional acrylates, and the like can be appropriately selected according to the type of rubber and the purpose of the rubber, and can be contained in necessary amounts.

The vulcanizing agent used in the present invention is used for ordinary rubber vulcanization, and is not particularly limited. Examples thereof include sulfur such as powdered sulfur, precipitated sulfur, colloidal sulfur and insoluble sulfur; Inorganic vulcanizing agents such as sulfur, selenium and tellurium; and sulfur-containing organic compounds such as morpholine disulfide, alkylphenol disulfide, thiuram disulfide and dithiocarbamate. One or more of these vulcanizing agents are used. The amount of the vulcanizing agent is preferably 0.1 parts by weight per 100 parts by weight of the rubber component.
To 15 parts by weight, more preferably 0.5 to 10 parts by weight. Among the vulcanizing agents, a particularly preferred one is sulfur. When sulfur is used as a vulcanizing agent, a vulcanization accelerator and a vulcanization accelerator can be used in combination, if necessary.

As the organic peroxide, 1,1-di-t-
Butylperoxy-3,3,5-trimethylcyclohexane, di-t-butyl peroxide, dicumyl peroxide, t-butylcumyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane,
1,3-bis- (t-butylperoxy-isopropyl) benzene and the like. The compounding amount of the organic peroxide is preferably 0.1 to 100 parts by weight of the rubber component.
It is 10 parts by weight, more preferably 1 to 7 parts by weight.

The vulcanization accelerator used in the present invention includes, for example, aldehyde ammonias such as hexamethylenetetramine (H); diphenylguanidine (D), di (o-
Guanidines such as tolyl) guanidine (DT), o-tolylpiguanide (BG); thiocarbanilide, di (o
-Tolyl) thiourea, N, N'-diethylthiourea (EUR), N, N'-dibutylthiourea (BU
R), thioureas such as N, N'-diphenylthiourea (C), tetramethylthiourea, trimethylthiourea, dilaurylthiourea (LUR); mercaptobenzothiazole (M), dibenzothiazodyl disulfide (DM), 2- Thiazoles such as (4-morpholinothio) benzothiazole, 2- (2,4-dinitrophenyl) -mercaptobenzothiazole, (N, N′-diethylthiocarbamoylthio) benzothiazole;
Oxydiethylene-2-benzothiazolylsulfenamide (NS, NOB), Nt-butyl-2-benzothiazolylsulfenamide (NS), N, N'-dicyclohexyl-2-benzothiazolylsulfenamide (CZ, CM), N, N'-diisopropyl-2-benzothiazylsulfenamide, N-cyclohexyl-2
Sulfenamides such as benzothiazylsulfenamide; tetramethylthiuram disulfide (TT, TM
T), tetraethylthiuram disulfide (TET),
Thiurams such as tetrabutylthiuram disulfide (TBT), tetramethylthiuram monosulfide (TS), dipentamethylenethiuram tetrasulfide (TRA); zinc dimethylthiocarbamate (PZ), zinc diethylthiocarbamate (EZ), -Zinc n-butylthiocarbamate (BZ), zinc ethylphenyldithiocarbamate, sodium dimethyldithiocarbamate (S, SDD, MSL), copper dimethyldithiocarbamate, tellurium diethylthiocarbamate (TL, TTT
E), carbamates such as iron dimethylthiocarbamate; and xanthates such as zinc butylthioxanthogenate. One or two or more of these vulcanization accelerators are used. The amount of the vulcanization accelerator is preferably 0.1 to 20 parts by weight, more preferably 0.2 to 10 parts by weight, per 100 parts by weight of the rubber component.

The vulcanization accelerator used in the present invention comprises:
For example, zinc oxide (zinc white, activated zinc white, surface-treated zinc white, composite zinc white, etc.), magnesium oxide, litharge,
Metal oxides such as red lead and white lead; organic acids such as stearic acid, oleic acid and zinc stearate; One or two or more of these vulcanization accelerators are used. The compounding amount of the vulcanization accelerator is preferably 0.5 to 20 parts by weight, more preferably 1 to 10 parts by weight, per 100 parts by weight of the rubber component.

In the case of the composition of the ethylene-α-olefin rubber, the polyfunctional acrylate ester preferably used in combination with the organic peroxide is preferably a liquid, specifically, ethylene glycol diacrylate, ethylene glycol diacrylate. Examples thereof include methacrylate, trimethylolpropane triacrylate, and triethylene glycol diacrylate.

The silane coupling agent used in the present invention includes, for example, vinyltrichlorosilane, vinyltriethoxysilane, vinyltris (β-methoxyethoxy) silane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, N- (β-aminoethyl) -γ-aminopropyltrimethoxysilane, N- (β-aminoethyl)-
γ-aminopropylmethyldimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, bis (3- (tri Examples thereof include tetrasulfides such as ethoxysilyl) propyl) tetrasulfide, γ-trimethoxysilylpropyldimethylthiocarbamyltetrasulfide, and γ-trimethoxysilylpropylbenzothiazyltetrasulfide. These silane coupling agents can be used alone or in combination of two or more. The mixing ratio of the silane coupling agent is silica 10
The amount is preferably 0.1 to 20 parts by weight, more preferably 1 to 10 parts by weight, based on 0 parts by weight.

The lubricant used in the present invention includes, for example,
Aliphatic hydrocarbons such as paraffin wax, polyethylene wax and polypropylene wax, capric acid,
Higher fatty acids such as lauric acid, myristic acid, palmitic acid, margaric acid, stearic acid, arachidic acid, behenic acid and metal salts thereof, such as palmityl such as lithium salt, calcium salt, sodium salt, magnesium salt and potassium salt Aliphatic alcohols such as alcohol, cetyl alcohol, and stearyl alcohol;
Aliphatic amides such as caproic acid amide, caprylic acid amide lauric acid amide, myristic acid amide, palmitic acid amide, stearic acid amide, esters of fatty acids and alcohols, fluoroalkylcarboxylic acids or metal salts thereof, and fluoroalkylsulfonic acids And fluorine compounds such as metal salts.

The fillers other than the carbon black and silica used in the present invention include heavy calcium carbonate, chalk, light calcium carbonate, ultra-fine activated calcium carbonate, lignin-treated calcium carbonate, basic magnesium carbonate, Magnesium, aluminum hydroxide, magnesium hydroxide, magnesium oxide, kaolin clay, calcined clay, pyrolite clay, kaolin, silanized clay, sericite, talc, finely divided talc, calcium silicate (wollastonite, zonotonite, petal silicic acid) Calcium), diatomaceous earth, aluminum silicate, mica, magnesium silicate, potassium titanate, erestadite, gypsum fiber, glass balun, silica balun, fly ash balun, silas balun, carbon balun, phenolic resin, thermosetting Organic baluns such as phenolic resin, urea resin, coumarone resin, styrene resin, and saran resin, alumina, barium sulfate, aluminum sulfate, calcium sulfate, molybdenum disulfide, graphite, glass fiber (chopped strand, roping, milled glass fiber , Glass flakes), cut fiber, rock fiber, microfiber, carbonated fiber, aromatic polyamide fiber, potassium titanate fiber, tackifier, ebonite powder, wood powder, ceramic, rubber powder, recycled rubber, potassium titanate fiber, pengala And cyanine green. These are used alone or in combination of two or more. The amount of these components is preferably 10 to 200 parts by weight, more preferably 20 to 100 parts by weight, based on 100 parts by weight of the rubber component. By blending these, the strength, elongation at break, hardness and the like of the vulcanized rubber can be increased.

The rubber composition of the present invention has no problem even if it is a blend with another polymer, depending on the intended use of the vulcanizate and the performance based thereon. The rubber composition of the present invention can be obtained by kneading the components using a kneading machine such as a roll, a Banbury mixer, a kneader, or an extruder according to a conventional method. The compounding method and the compounding order are not particularly limited. For example, using a Banbury mixer, a kneader, a roll, or the like, a rubber component, a filler,
After mixing a plasticizer or the like, a method of adding a vulcanizing agent, a vulcanization accelerator, a cross-linking accelerator and other rubber chemicals using a roll or the like may be used. In the rubber composition of the present invention, the mixing of the rubber and the sulfur compound can be performed by mechanically kneading as described above, but when the rubber is manufactured from a latex or rubber solution, the latex or A rubber containing a sulfur compound may be obtained by adding a sulfur compound to the rubber solution and co-coagulating with the rubber or removing the solvent with the rubber, and using the rubber to produce the rubber composition of the present invention.

The mixing temperature of the diene rubber and the compounding agent excluding the vulcanizing agent, the vulcanization accelerator and the vulcanization accelerator are usually 50 to 20.
0 ° C., and the mixing time is usually 30 seconds or more, preferably 1 to 30 minutes. The vulcanizing agent, the vulcanization accelerator and the mixing of the vulcanization accelerator are usually performed after cooling to 100 ° C. or less, preferably from room temperature to 80 ° C., and then usually from 120 to 2 ° C.
Vulcanization is carried out at a temperature of 00C, preferably 140-180C. The vulcanization of the rubber composition of the present invention includes, for example, press vulcanization, can vulcanization, injection molding vulcanization, hot air vulcanization, UHF
Vulcanization, LCM vulcanization, PCM vulcanization, etc., or a combination thereof can be carried out batchwise or continuously.

The rubber composition of the present invention contains a sulfur compound represented by the above-mentioned chemical formula (1), (2) or (3), so that its abrasion can be at least 10% as compared with a rubber composition not containing the sulfur compound. Can be reduced. Further, when vulcanized, the rubber composition of the present invention becomes a rubber product having excellent tensile strength, elongation and tensile stress, and having appropriate hardness. For this reason, the rubber composition of the present invention is suitable for the production of ordinary rubber products,
Various tires that require especially wear resistance, especially tire treads, rolls, especially milling rolls, various rollers,
It can be suitably used for producing belts, shoe soles, sealing materials for rotating parts, and the like.

[0029]

EXAMPLES The present invention will be described in more detail with reference to the following examples, but it should not be construed that the present invention is limited thereto. The parts and percentages in the examples are on a weight basis unless otherwise specified. Various physical properties in the following examples were evaluated by the following methods. (1) Mooney viscosity: Measured according to JIS K6300 (Mooney viscosity test) (ML _{1 + 4} , 100 ° C.). (2) Vulcanization properties; tensile strength, elongation and tensile stress
It is measured according to K6251. (3) Hardness: Measure JIS A hardness. (4) Akron abrasion: Measured under a load of 27 N using a disc-shaped test piece according to JIS K6264. The unit is CC
/ 1000 times or CC / 2000 times.

Example 1 160 parts of styrene-butadiene copolymer oil-extended rubber (SBR 1712) and carbon black HAF (6 inch roll) at a roll temperature of 50 ° C. and a rotation speed of 20/25 rpm before and after were used. N-330) 85 parts, aromatic oil 2
0 parts, zinc white 3 parts, stearic acid 2 parts, antioxidant (I
PPD; 1 part of Ozonone 3C, manufactured by Seiko Chemical Co., Ltd., sulfur compound (ADK STAB AO-23, manufactured by Adeka Argus Chemical Co., Ltd .; a mixture of the chemical formula (1) having 12 to 14 carbon atoms in the alkyl group) Knead with 1 part of sulfur.
5 parts and 1.2 parts of a vulcanization accelerator (NS) were added and kneaded. This rubber composition was put into a mold and press-vulcanized at 145 ° C. for 30 minutes to obtain a test piece for evaluating physical properties. Table 1 shows the composition of the rubber composition and the results of evaluation of the physical properties. Tables 4, 5 and 6 show the details of the raw materials used. Comparative Example 1 A rubber composition was produced in the same manner as in Example 1 except that no sulfur compound was added, and vulcanized to evaluate physical properties. Table 1 shows the composition of the rubber composition and the results of evaluation of the physical properties.

Example 2 100 parts of styrene-butadiene copolymer rubber (SBR 1502), silica 65 were used at a roll temperature of 70 ° C. and a rotation speed of 20/25 rpm using a 6-inch roll.
Parts, naphthenic oil 5 parts, zinc white 7 parts, stearic acid 1
Parts, Coumarone resin 5 parts, lignin-treated calcium carbonate 1
5 parts, 5 parts of titanium oxide, 2 parts of DEG (diethylene glycol) and 1 part of a sulfur compound (same as in Example 1) are kneaded, and 5 parts of sulfur and 1 part of a vulcanization accelerator (CZ) are mixed with those of Example 1. A rubber composition was produced in the same manner,
The mixture was press vulcanized in minutes to obtain a test piece for evaluating physical properties, and the physical properties were evaluated. Table 1 shows the composition of the rubber composition and the results of evaluation of the physical properties. Tables 4, 5 and 6 show the details of the raw materials used. Comparative Example 2 A rubber composition was produced and vulcanized to evaluate physical properties in exactly the same manner as in Example 2 except that no sulfur compound was added. Details are shown in Table 1.

Example 3 As a sulfur compound [Adecastab AO-412S, manufactured by Adeka Argus Chemical Co., Ltd .; corresponding to the chemical formula (3).
C (CH ₂ OCOCH ₂ CH ₂ SC ₁₂ H ₂₅ ) ₄ ] Except for using 1 part, a rubber composition was produced in the same manner as in Example 2 and vulcanized to evaluate physical properties. For details, see Tables 1, 4, 5,
The results are shown in FIG.

[0033]

[Table 1]

Example 4 100 parts of NBR, 40 parts of carbon black HAF (IRM # 7), and 5 parts of zinc white were used at a roll temperature of 50 ° C. and a rotation speed of 20/25 rpm using a 6-inch roll.
Part, stearic acid 1 part, antioxidant (SP-P) 1 part,
Sulfur compound (alkyl compound having 18 carbon atoms in the chemical formula (2); IRGANOX PS-, manufactured by Ciba-Geigy)
802) 1 part was kneaded, and further 1.5 parts of sulfur and 0.7 part of a vulcanization accelerator (NS) were kneaded to produce a rubber composition.
Press vulcanization was performed at 145 ° C. for 50 minutes to obtain a test piece for evaluating physical properties, and the physical properties were evaluated. Table 2 shows the composition of the rubber composition and the results of evaluation of the physical properties. Tables 4 and 5 show the details of the raw materials used.
The results are shown in FIG. Comparative Example 3 A rubber composition was produced and vulcanized in the same manner as in Example 4 except that no sulfur compound was added, and physical properties were evaluated. Details are shown in Table 2.

Example 5 Using a 6-inch roll, at a roll temperature of 75 ° C. and a rotational speed of 20/25 rpm, 100 parts of NBR, 70 parts of silica, 5 parts of DOP, 5 parts of zinc white, 5 parts of stearic acid,
Parts, 10 parts of phenolic resin, 2 parts of DEG, 1 part of antioxidant (SP-P), sulfur compound (Ciba-Geigy, I
1 part of RGANOX PS-802)
2 parts of sulfur and 1.5 parts of a vulcanization accelerator (CZ) were kneaded to produce a rubber composition, which was press-vulcanized at 150 ° C. for 60 minutes to obtain a test piece for evaluating physical properties, and the physical properties were evaluated. Table 2 shows the composition of the rubber composition and the results of evaluation of the physical properties. Tables 4, 5 and 6 show the details of the raw materials used.

Example 6 The NBR used in Example 6 was NBR, N2 of Example 5.
In the latex state of 30SL, 1PH of a sulfur compound (IRGANOX PS-802, manufactured by Ciba Geigy)
The experiment was carried out in exactly the same manner as in Example 5 except that R was emulsified, added to the NBR latex and mixed, co-coagulated and used as a solid rubber. In addition, at the time of kneading the rubber composition, no sulfur compound was added.

Example 7 Example 7 is an IR compound manufactured by Nippon Ciba Geigy Co., Ltd., which is a sulfur compound of an alkyl group having 12 carbon atoms in the chemical formula (2).
The experiment was carried out in exactly the same manner as in Example 5, except that 1 part of GANOX; PS-800 was added. Comparative Example 4 In Comparative Example 4, an experiment was performed in exactly the same manner as in Example 5, except that no sulfur compound was added. Examples 6 and 7 and Comparative Example 4
Table 2 shows the composition of the rubber composition and the results of evaluation of the physical properties.
Tables 4, 5 and 6 show the details of the raw materials used.

[0038]

[Table 2] Note 1: A sulfur compound is added to NBR in latex state and co-coagulated for use.

Example 8, Comparative Example 5 A 6-inch roll was used at a roll temperature of 50 ° C. and a rotation speed of 20/25 rpm before and after 100 parts of EPM, 40 parts of carbon black GPF and 40 parts of carbon black SRF3.
0 parts, 25 parts of paraffinic oil, 5 parts of zinc white, 1 part of stearic acid, sulfur compound (the one having an alkyl group having 14 carbon atoms in the chemical formula (2). In Comparative Example 5, no sulfur compound was added.)
, And 2 parts of ethylene glycol dimethacrylate (EDM) and 8 parts of DCP (40%).
A rubber composition was manufactured and press vulcanized at 160 ° C. for 20 minutes to obtain a test piece for evaluating physical properties, and the physical properties were evaluated. Table 3 shows the composition of the rubber composition and the results of evaluation of the physical properties. Tables 4, 5 and 6 show the details of the raw materials used.

[0040]

[Table 3]

[0041]

[Table 4]

[0042]

[Table 5]

[0043]

[Table 6]

[0044]

As is clear from Tables 1 to 3, the vulcanizates of the rubber composition containing the specific sulfur compound of the present invention are:
Compared with the case where the specific sulfur compound is not blended, the tensile stress, tensile strength, elongation, and physical properties of hardness are almost the same, and further, the result of the Akron abrasion test shows that the specific sulfur compound of the present invention is blended. In each case, the abrasion was small. As a result, the rubber composition of the present invention is a vulcanized rubber product requiring abrasion resistance, for example, a vehicle tread, a sidewall, a belt, various rolls, a milling roll, a roller, a shoe sole, a sealing material, and the like. Useful for the production of

[Procedure amendment]

[Submission date] July 17, 2000 (2007.1)
7)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0033

[Correction method] Change

[Correction contents]

[0033]

[Table 1]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0040

[Correction method] Change

[Correction contents]

[0040]

[Table 3]

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0041

[Correction method] Change

[Correction contents]

[0041]

[Table 4]

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Claims (5)

[Claims] 1 to 100 parts by weight of one or more rubbers selected from natural rubber and synthetic rubber, 5 to 250 parts by weight of one or more fillers selected from carbon black and silica, and the following chemical formula (1): A rubber composition containing 0.1 to 10 parts by weight of one or more sulfur compounds selected from (2) and (3). Embedded image ^{_{S (CH 2 CH 2 COOR 2}} ) 2 (2) C (CH 2 OCOCH 2 CH 2 SR 3) 4 (3) R 1, R 2 and R ³ in the above formula are both C _a H
An alkyl group represented by _{2a + 1} (a is an integer selected from 1 to 24); 2. A synthetic rubber comprising styrene-butadiene copolymer rubber, acrylonitrile-styrene-butadiene copolymer rubber, polybutadiene rubber, polyisoprene rubber, acrylonitrile-butadiene copolymer rubber, ethylene-α.
The rubber composition according to claim 1, wherein the rubber composition is selected from -olefin copolymer rubber and ethylene-α-olefin-diene copolymer rubber. 3. The sulfur of formulas (1), (2) and (3)
The compound is represented by the formula: ^One, R^TwoAnd R^ThreeHas 12 or 1 carbon atoms
4, 16 or 18 alkyl groups
The rubber composition according to claim 1. 4. A method for producing a tire tread using at least one rubber selected from natural rubber, polybutadiene rubber, polyisoprene rubber, styrene-butadiene copolymer rubber and acrylonitrile-styrene-butadiene copolymer rubber. The rubber composition according to claim 1, wherein 5. The rubber composition according to claim 1, wherein acrylonitrile-butadiene copolymer rubber is used as the synthetic rubber for producing a roll.