JP2010111742A - Rubber composition for vibration-proof rubber and vibration-proof rubber - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vibration-proof rubber composition improved both in heat resistance and fatigue resistance in a balanced manner after vulcanization, and a vibration-proof rubber. <P>SOLUTION: The vibration-proof rubber composition includes a rubber ingredient comprising natural rubber or a blend of natural rubber and diene-type synthetic rubber as a main ingredient, wherein 0.2-4 pts.wt. of a bismaleimide compound, 0.5-3.5 pts.wt. of a sulfenimide compound, and 0.5-6.5 pts.wt. of a thiazole compound are contained based on 100 pts.wt. of the rubber component. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a rubber composition for vibration-proof rubber. In particular, the present invention relates to a rubber composition for anti-vibration rubber that can be suitably used as an anti-vibration member for engine mounts, strut mounts, body mounts, suspension bushes, etc. of vehicles such as automobiles, and an anti-vibration rubber using the same. is there.

  Anti-vibration rubber is used for vehicles such as automobiles to absorb vibrations of the engine and the vehicle body and improve riding comfort and prevent noise. Anti-vibration rubber is generally required to have anti-vibration performance such as dynamic magnification, but not only that, but it is also required to have heat resistance when used in a high-temperature part such as an engine room or an exhaust system of an automobile. In particular, with the recent increase in engine output and the like, the heat resistance requirements for anti-vibration rubber have become more severe.

  Conventionally, natural rubber or a blend of natural rubber and diene synthetic rubber is generally used as the rubber component of the rubber composition for vibration-proof rubber from the viewpoint of low dynamic magnification and fatigue resistance. As a technique for improving the heat resistance of a rubber composition containing such a rubber component, a technique for reducing the amount of sulfur in the rubber composition and vulcanizing it with a large amount of a vulcanization accelerator, a so-called effective vulcanization technique It has been known.

  However, in the conventional effective vulcanization technology, the heat resistance of the vulcanized rubber can be improved to some extent by increasing the number of cross-linked forms due to monosulfide bonds, but it is in a situation where the above requirements cannot be sufficiently met. . In addition, by reducing the amount of sulfur and reducing the number of sulfide bonds at the crosslinking site, rubber elasticity and flexibility are lost, and the durability (ie, sag resistance) of the rubber composition deteriorates. Arise.

In order to improve the heat resistance of the vulcanized rubber, it has been proposed to introduce crosslinks other than sulfur. For example, Patent Document 1 below proposes using sulfur and N, N′-m-phenylenebismaleimide as vulcanizing agents, and further using sulfenamide compounds as vulcanization accelerators in the examples. Is disclosed. Patent Documents 2 and 3 below disclose that a bismaleimide compound is blended without blending sulfur as a vulcanizing agent and a thiazole compound is used as a vulcanization accelerator.
JP-A-3-258840 JP 2005-194501 A JP 2006-273941 A

  However, the above-mentioned conventional measures alone may not sufficiently meet the high heat resistance requirements of vibration-proof rubbers such as engine mounts, and improving both heat resistance and sag resistance in a balanced manner. difficult.

  This invention exists in the point which improves both the heat resistance of a rubber | gum after vulcanization | cure, and sag-proof property in the rubber composition for vibration-proof rubbers in view of the above point.

  As a result of intensive studies in view of the above problems, the present inventor has obtained heat resistance and sag resistance by using a sulfenimide compound and a thiazole compound as a vulcanization accelerator together with a bismaleimide compound as a crosslinking agent. The present inventors have found that it can be improved in a well-balanced manner and have completed the present invention.

That is, the rubber composition for vibration-proof rubber according to the present invention is the rubber composition for vibration-proof rubber containing a rubber component whose main component is natural rubber or a blend of natural rubber and diene synthetic rubber. 0.2 to 4 parts by weight of the bismaleimide compound, 0.5 to 3.5 parts by weight of the sulfenimide compound represented by the following general formula (1), and 0 thiazole compound with respect to 100 parts by weight of the component It is contained in an amount of 0.5 to 6.5 parts by weight.

  In formula, Y shows a C1-C18 hydrocarbon group.

  The vibration-proof rubber according to the present invention is obtained by vulcanization molding using the rubber composition for vibration-proof rubber.

  According to the rubber composition for vibration-proof rubber of the present invention, the heat resistance and sag resistance of the rubber after vulcanization can be improved in a well-balanced manner while improving the scorch property and improving the processability. Therefore, the vibration-proof rubber using the rubber composition has excellent heat resistance and sag resistance, and is therefore useful as a vibration-proof rubber for engine mounts that require high heat resistance.

  Hereinafter, matters related to the implementation of the present invention will be described in detail.

  The rubber composition for vibration-proof rubber according to the present invention comprises a rubber component (A), a bismaleimide compound (B) as a crosslinking agent, a sulfenimide compound (C) and a thiazole compound (D) as a vulcanization accelerator. ) And a combination.

  The rubber component as the component (A) is mainly composed of natural rubber or a blend of natural rubber and diene synthetic rubber. When the rubber composition contains such a rubber component, the vulcanized rubber has a low dynamic magnification (dynamic spring constant / static spring constant), which is an index as a dynamic characteristic required for the vibration-proof rubber. And resistance to repeated denaturation is increased.

  The rubber component may be natural rubber (NR) alone or a blend of natural rubber and diene synthetic rubber. Examples of the diene-based synthetic rubber include polyisoprene rubber (IR), polybutadiene rubber (BR), styrene-butadiene rubber (SBR), butyl rubber (IIR), acrylonitrile-butadiene rubber (NBR), and the like. The polymerization method and microstructure of these diene-based synthetic rubbers are not limited, and one or more of these can be used by blending with natural rubber.

  The blend ratio of the natural rubber and the diene-based synthetic rubber is not particularly limited, but it is preferable that the natural rubber is contained in the rubber component in an amount of 50% by weight or more, more preferably 90% in order to maintain the fatigue resistance performance of the natural rubber. % Or more.

  In addition to natural rubber and diene synthetic rubber, other synthetic rubbers may be blended with the rubber component. Examples of such synthetic rubbers include olefin rubbers such as ethylene propylene rubber (EPM), halogenated butyl rubbers such as brominated butyl rubber (Br-IIR), polyurethane rubber, acrylic rubber, fluorine rubber, silicon rubber, Examples include chlorosulfonated polyethylene. However, since the rubber component is composed mainly of natural rubber and diene synthetic rubber, other synthetic rubbers are blended within a range not impairing the effects of the present invention. The amount of component used should be less than 50% by weight of the rubber component.

As the bismaleimide compound of the component (B) as a crosslinking agent, those represented by the following general formula (2) are preferably used.

In the formula, R ^{1 to} R ⁴ represent a hydrogen atom, an alkyl group, an amino group (—NH ₂ ), a nitro group (—NO ₂ ), or a nitroso group (—NO), and may be the same or different from each other. Good. X represents a divalent organic group.

Regarding R ^{1 to} R ⁴ , examples of the alkyl group include lower alkyl groups having 1 to 5 carbon atoms such as a methyl group, an ethyl group, and a propyl group.

The divalent organic group represented by X is preferably an aliphatic saturated hydrocarbon group, an aromatic hydrocarbon group, or a hydrocarbon group having an aromatic ring, which may or may not have a substituent. Good. More specifically, examples include an alkylene group having 4 to 12 carbon atoms, a phenylene group, and a hydrocarbon group having 1 to 4 aromatic rings and including a hetero atom in the main chain. Examples of the substituent include an alkyl group (preferably a lower alkyl group having 1 to 5 carbon atoms such as a methyl group, an ethyl group, and a propyl group), —NO ₂ , —NH ₂ , —F, —Cl, —Br, and the like. Is mentioned. In the hydrocarbon group having an aromatic ring, examples of the hetero atom that may be contained in the main chain include an oxygen atom and a sulfur atom. More specifically, each aromatic ring is -O-, -S-, Examples include an embodiment in which they are bonded by —SS—, —SO ₂ — or the like.

As a specific example of a preferable bismaleimide compound, N, N ′-(4,4′-diphenylmethane) bismaleimide (BMI-HS manufactured by Keiai Kasei Co., Ltd.) represented by the following formula (2-1), 2-2) N, N′-m-phenylene dimaleimide (manufactured by Ouchi Shinsei Chemical Co., Ltd., Barnock PM-P), 2,2′-bis represented by the following formula (2-3) [4- (4-Maleimidophenoxy) phenyl] propane (manufactured by Keisei Kasei Co., Ltd., BMI-80), bis (3-ethyl-5-methyl-4-maleimidophenyl) methane represented by the following formula (2-4) (Kai Kasei Co., Ltd., BMI-70), 1,6-hexanediyl bismaleimide represented by the following formula (2-5), and the like can be given.

  The content of the bismaleimide compound is 0.2 to 4 parts by weight with respect to 100 parts by weight of the rubber component. When the content of the bismaleimide compound is less than 0.2 parts by weight, both the heat resistance and the sag resistance cannot be improved in a balanced manner, and particularly the sag resistance is inferior. When the content exceeds 4 parts by weight, the scorch property is deteriorated and rubber scoring is likely to occur. In order to further improve the heat resistance and sag resistance of the vulcanized rubber while maintaining good scorch properties, the content of the bismaleimide compound is 0.5 to 3 weights with respect to 100 parts by weight of the rubber component. More preferably, it is a part.

  As the sulfenimide compound of the component (C) as a vulcanization accelerator, those represented by the general formula (1) are used. By blending such a sulfenimide compound, the scorch time can be lengthened and the processability can be improved. Further, by using in combination with the (B) component bismaleimide compound and the (D) component thiazole compound, both the heat resistance and sag resistance of the vulcanized rubber can be improved in a well-balanced manner. Such an effect is not exhibited by the sulfenamide compound, and is unique to the sulfenimide compound. That is, when a sulfenamide compound is used in combination with a thiazole compound instead of a sulfenimide compound, the scorch property is deteriorated, and the heat resistance and sag resistance improvement effect of the vulcanized rubber cannot be obtained.

In the above formula (1), Y includes more specifically a C1-C18 linear alkyl group, branched alkyl group, alicyclic hydrocarbon group, and aromatic hydrocarbon group. As the sulfenimide compound, when considering the dispersibility in the rubber composition, the vulcanization acceleration effect, and the change rate of vibration characteristics when used as a vulcanized rubber for a long time, the substituent Y is a t-butyl group. N-t-butyl-di (2-benzothiazole) sulfenimide, N-cyclohexyl-di (2-benzothiazole) sulfenimide in which substituent Y is a cyclohexyl group, and substituent Y is a phenyl group N-phenyl-di (2-benzothiazole) sulfenimide is preferred. More preferably, Nt-butyl-di (2-benzothiazole) sulfenimide represented by the following formula (1-1) (manufactured by FLEXSYS, SANTOCURE TBSI), and the following formula (1-2) N-cyclohexyl-di (2-benzothiazole) sulfenimide represented.

  Content of a sulfenimide compound is 0.5-3.5 weight part with respect to 100 weight part of rubber components. When the content of the sulfenimide compound is less than 0.5 parts by weight, it is impossible to improve both heat resistance and sag resistance in a well-balanced manner while ensuring good scorch properties. When the content exceeds 3.5 parts by weight, the scorch property is deteriorated and rubber scoring is likely to occur. The content of the sulfenimide compound is more preferably 1 to 3 parts by weight with respect to 100 parts by weight of the rubber component.

As the thiazole compound of the above component (D) as a vulcanization accelerator, a 2-thiobenzothiazole compound is preferably used. Specifically, di-2-benzothiazolyl disulfide represented by the following formula (3-1), 2-mercaptobenzothiazole represented by the following formula (3-2), and the following formula (3-3). 2- (4′-morpholinodithio) benzothiazole and a salt of 2-mercaptobenzothiazole (for example, zinc salt, sodium salt, cyclohexylamine salt) and the like.

  The content of the thiazole compound is 0.5 to 6.5 parts by weight with respect to 100 parts by weight of the rubber component. If the content of the thiazole compound is less than 0.5 parts by weight, both the heat resistance and sag resistance of the vulcanized rubber cannot be improved, and the sag resistance is particularly inferior. When the content exceeds 6.5 parts by weight, the scorch property is deteriorated and rubber scoring is likely to occur, and the sag resistance tends to be deteriorated. The content of the thiazole compound is more preferably 1 to 5 parts by weight.

  In addition to the above components (A) to (D), it is preferable to further add sulfur (E) as a crosslinking agent to the rubber composition for vibration-proof rubber according to the present invention. As sulfur, normal rubber sulfur can be used, and examples thereof include powdered sulfur, precipitated sulfur, insoluble sulfur, and highly dispersible sulfur. The sulfur content is preferably 0.1 to 1.3 parts by weight with respect to 100 parts by weight of the rubber component. In such a low sulfur compounding system, which is a compounding system having a small amount of sulfur, by combining the bismaleimide compound (B), the sulfenimide compound (C) and the thiazole compound (D), heat resistance and sag resistance are improved. Both can be further improved. If the sulfur content is less than 0.1 parts by weight, the crosslinking density of the vulcanized rubber is insufficient and the rubber strength and the like are reduced, and if it exceeds 1.3 parts by weight, the heat resistance tends to deteriorate.

  In the rubber composition for vibration-proof rubber according to the present invention, a vulcanization accelerator other than the sulfenimide compound (C) and the thiazole compound (D) may be additionally used as a vulcanization accelerator. . Examples of such vulcanization accelerators include thiuram vulcanization accelerators, sulfenamide vulcanization accelerators, thiourea vulcanization accelerators, guanidine vulcanization accelerators, and thiocarbamate vulcanization accelerators. Agents and the like. Among these, the thiuram compound is preferably used in combination with the sulfenimide compound (C) and the thiazole compound (D), and the heat resistance of the vulcanized rubber can be further improved. Examples of thiuram compounds include tetramethylthiuram monosulfide, tetramethylthiuram disulfide, tetraethylthiuram disulfide, tetrabutylthiuram disulfide, dipentamethylenethiuram tetrasulfide, dipentamethylenethiuram hexasulfide, and tetrakis (2-ethylhexyl) thiuram disulfide. Etc. When the thiuram compound is blended, the blending amount is not particularly limited, but is preferably 0.1 to 2 parts by weight with respect to 100 parts by weight of the rubber component.

  In addition to the above components, the rubber composition for vibration-proof rubber according to the present invention includes fillers such as carbon black and silica, silane coupling agents, zinc oxide, stearic acid, vulcanization acceleration aids, vulcanization retarders, Various additives usually used in the rubber industry, such as organic peroxides, anti-aging agents, softeners such as waxes and oils, processing aids, etc., can be appropriately blended within the range not impairing the effects of the present invention. .

  Examples of carbon black include SAF, ISAF, HAF, FEF, and GPF. Carbon black can be used within a range in which rubber properties such as hardness, reinforcement and low heat build-up of the rubber after vulcanization can be adjusted. The blending amount of carbon black is not particularly limited, but is preferably 20 to 120 parts by weight, more preferably 30 to 100 parts by weight, and further preferably 30 to 60 parts by weight with respect to 100 parts by weight of the rubber component. . When the blending amount is less than 20 parts by weight, the reinforcing effect by carbon black cannot be sufficiently obtained. Conversely, when the blending amount exceeds 120 parts by weight, exothermic property, rubber mixing property, workability during processing, and the like deteriorate.

  Anti-aging agents include aromatic amine anti-aging agents, amine-ketone anti-aging agents, monophenol anti-aging agents, bisphenol anti-aging agents, polyphenol anti-aging agents, imidazole anti-aging agents, dithiocarbamates Examples thereof include aging inhibitors, thiourea aging inhibitors, and the like, and these can be used alone or in appropriate combination. Among these, it is preferable to use an imidazole compound as a secondary anti-aging agent together with a primary anti-aging agent such as an aromatic amine-based anti-aging agent. The heat resistance of the vulcanized rubber can be further improved by using the imidazole compound in combination with the above components (B) to (D).

  As the imidazole compound, a compound having a 2-mercaptobenzimidazole skeleton is preferable. More specifically, 2-mercaptobenzimidazole, 2-mercaptoalkylbenzimidazole, and metal salts thereof are preferable. Specifically, 2-mercaptobenzimidazole zinc salt (Nouchi MBZ manufactured by Ouchi Shinsei Chemical Co., Ltd.), 2-mercaptobenzimidazole (Nocrack MB manufactured by Ouchi Shinsei Chemical Co., Ltd.), and 2-mercaptomethylbenz Examples thereof include imidazole (manufactured by Ouchi Shinsei Chemical Industry Co., Ltd., NOCRACK MMB). When the imidazole compound is blended, the blending amount is not particularly limited, but is preferably 0.5 to 4.5 parts by weight with respect to 100 parts by weight of the rubber component.

  The rubber composition for vibration-proof rubber according to the present invention can be obtained by kneading using a usual method, for example, a kneader such as a Banbury mixer, a kneader, or a roller. The blending method of each component is not particularly limited. Usually, a method is preferably used in which compounding components other than the vulcanization system components such as a crosslinking agent and a vulcanization accelerator are kneaded in advance, and then the remaining components are added and kneaded.

  The rubber composition thus obtained can be subjected to vulcanization after molding into a predetermined shape to obtain a vibration-proof rubber. Specific examples of anti-vibration rubber include engine mounts, strut mounts, body mounts, cab mounts, member mounts, differential mounts, etc., suspension bushings, arm bushings, torque bushings, etc., torsional dampers, muffler hangers, dampers Anti-vibration rubber for automobiles such as pulleys and dynamic dampers. In addition to automobiles, it can be suitably used for anti-vibration rubber for railway vehicles, anti-vibration rubber for industrial machinery, seismic isolation rubber for construction, seismic isolation rubber bearings, etc., and seismic isolation rubber. In particular, it is useful as a constituent member of an automobile anti-vibration rubber that requires heat resistance such as an engine mount.

  Examples of the present invention will be described below, but the present invention is not limited to these examples.

  The rubber compositions of Examples and Comparative Examples were blended according to the blending shown in Tables 1 to 6 below, and kneaded using a Banbury mixer to prepare rubber compositions. Each component in Tables 1 to 6 is as follows.

・ Natural rubber: RSS # 3,
・ Carbon black: FEF, “Seast SO” manufactured by Tokai Carbon Co., Ltd.
・ Sulfenimide compound: Nt-butyl-di (2-benzothiazole) sulfenimide, “SANTOCURE TBSI” manufactured by FLEXSYS,
Thiazole compound (1): di-2-benzothiazolyl disulfide, “Noxeller DM-P (DM)” manufactured by Ouchi Shinsei Chemical Industry Co., Ltd.
Thiazole compound (2): 2-mercaptobenzothiazole, “Noxeller MP (M)” manufactured by Ouchi Shinsei Chemical Co., Ltd.
Thiazole compound (3): 2- (4′-morpholinodithio) benzothiazole, “Noxeller MDB-P (MDB)” manufactured by Ouchi Shinsei Chemical Industry Co., Ltd.
Bismaleimide compound (1): N, N ′-(4,4′-diphenylmethane) bismaleimide, “BMI-HS” manufactured by Keiai Kasei Co., Ltd.
Bismaleimide compound (2): N, N′-m-phenylene dimaleimide, “Barunok PM-P” manufactured by Ouchi Shinsei Chemical Co., Ltd.
Bismaleimide compound (3): 2,2′-bis [4- (4-maleimidophenoxy) phenyl] propane, “BMI-80” manufactured by Keiai Kasei Co., Ltd.
Bismaleimide compound (4): 1,6-hexanediyl bismaleimide,
Sulfenamide compound: Nt-butyl-2-benzothiazolylsulfenamide, “Noxeller NS-P (NS)” manufactured by Ouchi Shinsei Chemical Co., Ltd.

  In each rubber composition, 5 parts by weight of aroma oil ("Process X-140" manufactured by Japan Energy Co., Ltd.), 5 parts by weight of zinc oxide (No. 3 zinc white), 100 parts by weight of rubber component, as a common formulation 1 part by weight of acid (industrial stearic acid), 2 parts by weight of wax (microcrystalline wax, manufactured by Nippon Seiwa Co., Ltd.), aromatic amine type antioxidant (N- (1-methylheptyl) -N′-phenyl-p -Phenylenediamine, "Ozonon 35PR" manufactured by Seiko Chemical Co., Ltd.) 1.5 parts by weight, aromatic amine-based antioxidant (N- (1,3-dimethylbutyl) -N'-phenyl-p-phenylenediamine, Ouchi 1 part by weight of imidazole anti-aging agent (2-mercaptobenzimidazole zinc salt, “NOCRACK MBZ” manufactured by Ouchi Shinsei Chemical Co., Ltd.) Parts by weight, 0.4 parts by weight of thiuram vulcanization accelerator (tetramethylthiuram monosulfide, “Noxeller TS (TS-P)” manufactured by Ouchi Shinsei Chemical Industry Co., Ltd.), and sulfur (5% oil-treated sulfur) 0 6 parts by weight were blended.

  Each rubber composition was evaluated for scorch properties, and heated and vulcanized at 150 ° C. for 20 minutes using a predetermined mold to prepare a vulcanized rubber test piece, which had heat resistance and sag resistance. Evaluated. Each evaluation method is as follows.

Heat resistance: Retention rate of elongation at break in a tensile test after heat aging at 100 ° C. for 500 hours with respect to the elongation at break in a tensile test before heat aging for a sample prepared using JIS No. 3 dumbbells in accordance with JIS K6251 (%) Was calculated. In the evaluation, the retention rate of elongation at break calculated for the vulcanized rubber of Comparative Example 13 was taken as a control (ie, 100), and an improvement of 5% or more was observed with respect to the control (ie, 105 or more). ○ (Good) ”5% or more of deterioration (ie, 95 or less) is“ x (bad) ”, the difference with respect to the control is less than 5% (ie, more than 95 and less than 105)“ − (Equivalent) ”.

-Sag resistance: Based on JIS K6262, the compression set test (25% compression, 100 degreeC x 500 hours) was performed, and the compression set rate (%) was measured. In the evaluation, the compression set rate measured for the vulcanized rubber of Comparative Example 13 was taken as a control (ie, 100), and an improvement of 5% or more was observed with respect to the control (ie, 95 or less). (Good) ”5% or more of deterioration was observed (ie, 105 or more)“ × (bad) ”, and the difference with respect to the control was less than 5% (ie, more than 95 and less than 105)“-( Equivalent) ”.

Scorch resistance: conforming to JIS K6300, was measured scorch time _{t 5} at a test temperature of 125 ° C.. In the evaluation, the scorch time measured for the rubber composition of Comparative Example 13 was taken as a control (ie, 100), and an improvement of 5% or more was observed with respect to the control (ie, 105 or more). ) ”5% or more of deterioration (ie, 95 or less) is“ x (bad) ”, and the difference from the control is less than 5% (ie, more than 95 and less than 105) is“ − (equivalent) ” Was evaluated.

  The results are as shown in Tables 1 to 6 below. As shown in Table 1, when a bismaleimide compound and a thiazole compound are used in combination, when the sulfenimide compound is not blended, it is possible to improve the heat resistance and the sag resistance in a well-balanced manner while maintaining the scorch property. could not. As shown in Tables 2-5, by using the bismaleimide compound, the sulfenimide compound, and the thiazole compound in combination, the scorch property is improved and both heat resistance and sag resistance are improved in a well-balanced manner. I was able to. However, in Comparative Examples 38 to 41, the blending amount of the thiazole compound was too large, and the sag resistance deteriorated. Further, in Comparative Examples 56 and 57, although the sag resistance was improved due to the effects of the sulfenimide compound and the bismaleimide compound, the amount of the thiazole compound was too large, the scorch property was deteriorated. As shown in Table 6, when the amount of the sulfenimide compound was too large, the scorch property was deteriorated, and therefore, the processability at the time of producing the vibration-proof rubber was inferior.

As shown in Table 4, in Comparative Example 58 in which a sulfenamide compound was blended in place of the sulfenimide compound, the scorch property and sag resistance were deteriorated, as in the case of using the sulfenimide compound. An excellent effect was not obtained.

Claims (6)

In the rubber composition for vibration-proof rubber containing a rubber component whose main component is natural rubber or a blend of natural rubber and diene synthetic rubber,
0.2 to 4 parts by weight of a bismaleimide compound, 0.5 to 3.5 parts by weight of a sulfenimide compound represented by the following general formula (1), and a thiazole compound with respect to 100 parts by weight of the rubber component A rubber composition for vibration-proof rubber, containing 0.5 to 6.5 parts by weight.

(In the formula, Y represents a hydrocarbon group having 1 to 18 carbon atoms.)   The sulfenimide compound is at least one selected from Nt-butyl-di (2-benzothiazole) sulfenimide and N-cyclohexyl-di (2-benzothiazole) sulfenimide. The rubber composition for vibration-proof rubber according to 1. The rubber composition for vibration-proof rubber according to claim 1 or 2, wherein the bismaleimide compound is represented by the following general formula (2).

(Wherein, R ¹ to R ⁴ is a hydrogen atom, an alkyl group, an amino group, a nitro group or a nitroso group, good .X it is the same or different from each other, represents a divalent organic group. )   The bismaleimide compound is N, N ′-(4,4′-diphenylmethane) bismaleimide, N, N′-m-phenylenedimaleimide, 2,2′-bis [4- (4-maleimidophenoxy) phenyl]. The rubber composition for vibration-proof rubber according to claim 3, which is at least one selected from propane, bis (3-ethyl-5-methyl-4-maleimidophenyl) methane, and 1,6-hexanediylbismaleimide.   The thiazole compound is at least one selected from di-2-benzothiazolyl disulfide, 2-mercaptobenzothiazole, 2- (4′-morpholinodithio) benzothiazole, and a salt of 2-mercaptobenzothiazole. The rubber composition for vibration-proof rubber according to any one of claims 1 to 4.   Anti-vibration rubber obtained by vulcanization molding using the rubber composition for anti-vibration rubber according to any one of claims 1 to 5.