Anti-vibration rubber composition and anti-vibration rubber member

Abstract

Provided are an anti-vibration rubber composition and an anti-vibration rubber member with which it is possible to suppress deterioration in durability while improving reversion resistance. An anti-vibration rubber composition which contains the following components (A) to (E), and which is characterized in that the content of component (B) is 0.6-5.5 parts by mass, the content of component (C) is 0.45-3.5 parts by mass, the content of component (D) is 0.25-5.5 parts by mass, and the mass ratio ((C) / (D)) of component (C) to component (D) is 0.15-5.0 per 100 parts by mass of component (A), (A) is a diene rubber, (B) is a bismaleimide compound, (C) is a sulfenamide vulcanization accelerator, and (D) is a sulfur vulcanizing agent. And (E) an inorganic filler.

Description

Technical Field

[0001] The present invention relates to an anti-vibration rubber composition and an anti-vibration rubber member for use in anti-vibration applications in vehicles such as automobiles and trains. Background Art

[0002] Anti-vibration rubber compositions containing diene rubbers such as natural rubber may revert to vulcanization when in an over-vulcanized state. Reversion is a phenomenon in which polysulfide bonds and disulfide bonds are converted into monosulfide bonds, and the monosulfide bonds undergo a cleavage reaction accompanied by the formation of thiophene rings, thereby reducing the vulcanization density, and there is a concern that various properties may deteriorate.

[0003] Several methods for improving the reversion resistance of the anti-vibration rubber composition have been proposed. For example, as an anti-reversion agent added to the anti-vibration rubber composition, 1,3-bis(citraconimidomethyl)benzene, 1,6-sodium hexamethylene dithiosulfate (for example, see Patent Document 1, etc.), zinc monomethacrylate (ZMMA), etc. have been proposed.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2007-146035 Summary of the invention

[0007] Problems to be solved by the invention

[0008] However, in anti-vibration rubber compositions, research focusing not only on improving the reversion resistance but also on achieving a high balance between the reversion resistance and durability has not been sufficiently conducted.

[0009] The present invention has been made in view of the above circumstances, and provides a vibration-proof rubber composition capable of improving the reversion resistance and suppressing the decrease in durability.

[0010] Means used to solve problems

[0011] That is, the inventors of the present invention have focused on the following aspects during various studies on methods for improving the reversion resistance of the anti-vibration rubber composition: in the method using the above-mentioned anti-reversion agent, the reversion resistance is improved, but on the other hand, the durability is sometimes reduced due to the density of the cross-linked structure, etc.

[0012] The inventors of the present invention have further conducted studies from the viewpoint of achieving a high balance between reversion resistance and durability, and as a result, unexpectedly found that by controlling the contents of the bismaleimide compound, the sulfenamide vulcanization accelerator, and the sulfur-based vulcanizing agent within specific ranges, and controlling the mass ratio of the sulfenamide vulcanization accelerator to the sulfur-based vulcanizing agent within a specific range, it is possible to provide a vibration-proof rubber composition capable of improving reversion resistance while suppressing a decrease in durability.

[0013] That is, the gist of the present invention lies in the following [1] to

[13] .

[0014] [1] An anti-vibration rubber composition comprising the following components (A) to (E), characterized in that, relative to 100 parts by mass of the component (A), the content of the component (B) is 0.6 to 5.5 parts by mass, the content of the component (C) is 0.45 to 3.5 parts by mass, the content of the component (D) is 0.25 to 5.5 parts by mass, and the mass ratio of the component (C) to the component (D) [(C) / (D)] is 0.15 to 5.0.

[0015] (A) diene rubber,

[0016] (B) a bismaleimide compound,

[0017] (C) sulfenamide-based vulcanization accelerators,

[0018] (D) sulfur-based vulcanizing agent,

[0019] (E) Inorganic filler.

[0020] [2] The vibration-proof rubber composition according to [1], wherein the content of the (D) sulfur-based vulcanizing agent is 0.5 to 5.5 parts by mass.

[0021] [3] The vibration-proof rubber composition according to [1] or [2], wherein the mass ratio of the (C) sulfenamide vulcanization accelerator to the (D) sulfur vulcanizing agent [(C) / (D)] is 0.15 to 1.35.

[0022] [4] The vibration-proof rubber composition according to any one of [1] to [3], wherein the mass ratio of the (B) bismaleimide compound to the (C) sulfenamide vulcanization accelerator [(B) / (C)] is 0.4 to 5.5.

[0023] [5] The vibration-proof rubber composition according to any one of [1] to [4], comprising N,N′-m-phenylene bismaleimide as the (B) bismaleimide compound.

[0024] [6] The vibration-proof rubber composition according to any one of [1] to [5], comprising one or more selected from the group consisting of N-cyclohexyl-2-benzothiazolesulfenamide and N-oxydiethylene-2-benzothiazolesulfenamide as the (C) sulfenamide-based vulcanization accelerator.

[0025] [7] The vibration-proof rubber composition according to any one of [1] to [6], comprising at least one selected from the group consisting of carbon black and silica as the (E) inorganic filler.

[0026] [8] The vibration-proof rubber composition according to any one of [1] to [7], comprising a rubber having a BET specific surface area of ​​10 to 150 m 2 / g of carbon black as the (E) inorganic filler.

[0027] [9] The vibration-proof rubber composition according to any one of [1] to [8], comprising carbon black having an iodine adsorption amount of 10 to 150 mg / g as the (E) inorganic filler.

[0028]

[10] The vibration-proof rubber composition according to any one of [1] to [9], further comprising a thiuram-based vulcanization accelerator.

[0029]

[11] A vibration-proofing rubber member, comprising a vulcanized body of the vibration-proofing rubber composition according to any one of [1] to

[10] .

[0030]

[12] The vibration-proofing rubber member according to

[11] , wherein the vibration-proofing rubber member is a vibration-proofing rubber member for a vehicle.

[0031]

[13] The vibration-proofing rubber member according to

[12] , wherein the vibration-proofing rubber member is a vibration-proofing rubber member for use as a component of an engine mount, a stabilizer bushing, or a suspension bushing.

[0032] Effects of the Invention

[0033] The anti-vibration rubber composition of the present invention can provide an anti-vibration rubber composition capable of improving the reversion resistance and suppressing the decrease in durability. DETAILED DESCRIPTION

[0034] The embodiments of the present invention will be described in detail, but the present invention is not limited to these embodiments.

[0035] An anti-vibration rubber composition as one embodiment of the present invention (hereinafter, sometimes referred to as "the present anti-vibration rubber composition") is a anti-vibration rubber composition containing components (A) to (E), characterized in that, relative to 100 parts by mass of the component (A), the content of the component (B) is 0.6 to 5.5 parts by mass, the content of the component (C) is 0.45 to 3.5 parts by mass, the content of the component (D) is 0.25 to 5.5 parts by mass, and the mass ratio of the component (C) to the component (D) [(C) / (D)] is 0.15 to 5.0,

[0036] (A) diene rubber,

[0037] (B) a bismaleimide compound,

[0038] (C) sulfenamide-based vulcanization accelerators,

[0039] (D) sulfur-based vulcanizing agent,

[0040] (E) Inorganic filler.

[0041] In the present invention, in the vibration-proof rubber composition containing components (A) to (E), it is important to control the contents of the (B) bismaleimide compound, the (C) sulfenamide vulcanization accelerator, and the (D) sulfur vulcanizing agent within a specific range, and to control the mass ratio of the (C) sulfenamide vulcanization accelerator to the (D) sulfur vulcanizing agent within a specific range. If these are not controlled within a specific range, it is not possible to suppress the decrease in durability while improving the reversion resistance, and thus the problem of the present invention cannot be fully solved.

[0042] Hereinafter, constituent materials and the like of the vibration-proof rubber composition will be described in detail.

[0043] [(A) Diene rubber]

[0044] The vibration-proof rubber composition contains (A) diene rubber as a rubber component. As (A) diene rubber, for example, natural rubber (NR), butadiene rubber (BR), styrene-butadiene rubber (SBR), chloroprene rubber (CR), isoprene rubber (IR), acrylonitrile-butadiene rubber (NBR), ethylene-propylene-diene rubber (EPDM), butyl rubber (IIR), chloroprene rubber (CR), etc. can be listed. They can be used alone or in combination of two or more. Among them, natural rubber (NR) is preferred from the viewpoint of improving durability.

[0045] The (A) diene rubber used in the vibration-proof rubber composition is preferably a diene rubber containing natural rubber (NR) as a main component. Here, the "main component" means that the (A) diene rubber contains 50% by mass or more, preferably 60% by mass or more, more preferably 70% by mass or more, further preferably 80% by mass or more, and particularly preferably 90 to 100% by mass, relative to the total amount (100% by mass) of the diene rubber.

[0046] In addition, the vibration-proof rubber composition preferably contains substantially no rubber component other than the (A) diene rubber. For example, the content of the rubber component other than the (A) diene rubber is less than 1 part by mass, preferably less than 0.1 part by mass, and more preferably 0 part by mass, relative to 100 parts by mass of the (A) diene rubber.

[0047] The content of the (A) diene rubber contained in the present anti-vibration rubber composition is usually 45% by mass or more, preferably about 45 to 70% by mass, or about 50 to 65% by mass, based on the total amount (100% by mass) of the present anti-vibration rubber composition.

[0048] [(B) Bismaleimide compounds]

[0049] This vibration-proof rubber composition contains a specific amount of (B) bismaleimide compound. As (B) bismaleimide compound, for example, N, N'-m-phenylene bismaleimide, N, N'-o-phenylene bismaleimide, N, N'-p-phenylene bismaleimide, N, N'-(4, 4'-diphenylmethane) bismaleimide, 2, 2-bis [4- (4-maleimide phenoxy) phenyl] propane, bis (3-ethyl-5-methyl-4-maleimide phenyl) methane, etc. They can be used alone or in combination of two or more. Among them, from the viewpoint of taking into account both vulcanization reversion resistance and durability, N, N'-m-phenylene bismaleimide is preferred.

[0050] From the viewpoint of achieving both reversion resistance and durability, it is important to make the content of the (B) bismaleimide compound 0.6 to 5.5 parts by mass relative to 100 parts by mass of the (A) diene rubber. Outside this range, there is a tendency for durability to decrease, making it difficult to achieve both reversion resistance and durability.

[0051] From the viewpoint of further improving the reversion resistance and durability, the content of the bismaleimide compound (B) is preferably 0.7 to 5.2 parts by mass.

[0052] [(C) Sulfenamide-based vulcanization accelerator]

[0053] This vibration-proof rubber composition contains a specific amount of (C) sulfonamide-based vulcanization accelerator. As (C) sulfonamide-based vulcanization accelerator, for example, N-oxydiethylene-2-benzothiazole sulfonamide (NOBS), N-cyclohexyl-2-benzothiazole sulfonamide (CBS), N-tert-butyl-2-benzothiazole sulfonamide (BBS), N,N'-dicyclohexyl-2-benzothiazole sulfonamide, etc. can be cited. They can be used alone or in combination of two or more. Among them, from the viewpoint of taking into account both vulcanization reversion resistance and durability, preferably N-cyclohexyl-2-benzothiazole sulfonamide (CBS), N-oxydiethylene-2-benzothiazole sulfonamide (NOBS).

[0054] In addition, from the viewpoint of achieving both reversion resistance and durability and improving scorch resistance (storage stability), N-oxydiethylene-2-benzothiazolesulfenamide (NOBS) is preferred.

[0055] From the viewpoint of achieving both reversion resistance and durability, it is important to make the content of the (C) sulfenamide vulcanization accelerator 0.45 to 3.5 parts by mass relative to 100 parts by mass of the (A) diene rubber. Outside this range, there is a tendency for durability to decrease, making it difficult to achieve both reversion resistance and durability.

[0056] From the viewpoint of further improving the reversion resistance and durability, the content of the (C) sulfenamide-based vulcanization accelerator is preferably 0.45 to 3.2 parts by mass.

[0057] From the viewpoint of achieving both reversion resistance and durability, the mass ratio of the (B) bismaleimide compound to the (C) sulfenamide vulcanization accelerator [(B) / (C)] is preferably 0.4 to 8.0, more preferably 0.4 to 5.5, and even more preferably 0.5 to 2.0.

[0058] [(D) Sulfur-based vulcanizing agent]

[0059] The vibration-proof rubber composition contains a specific amount of (D) a sulfur-based vulcanizing agent. Examples of the (D) sulfur-based vulcanizing agent include sulfur (powdered sulfur, precipitated sulfur, insoluble sulfur), sulfur-containing compounds such as alkylphenol disulfide, etc. These can be used alone or in combination of two or more.

[0060] From the viewpoint of taking into account both the reversion resistance and the durability, it is important to make the content of the (D) sulfur-based vulcanizing agent 0.25 to 5.5 parts by mass relative to 100 parts by mass of the (A) diene rubber. When it is outside this range, there is a tendency for the reversion resistance and the durability to decrease, so it is difficult to take into account both the reversion resistance and the durability.

[0061] From the viewpoint of further improving the reversion resistance and durability, the content of the sulfur-based vulcanizing agent (D) is preferably 0.5 to 5.5 parts by mass.

[0062] From the viewpoint of achieving both reversion resistance and durability, it is important to set the mass ratio of the (C) sulfenamide vulcanization accelerator to the (D) sulfur vulcanizing agent [(C) / (D)] to 0.15 to 5.0. Outside this range, durability tends to decrease, making it difficult to achieve both reversion resistance and durability.

[0063] From the viewpoint of further improving the reversion resistance and durability, the mass ratio [(C) / (D)] is preferably 0.15 to 2, more preferably 0.15 to 1.35.

[0064] [(E) Inorganic filler]

[0065] The vibration-proof rubber composition contains (E) an inorganic filler. Examples of the (E) inorganic filler include carbon black, silica, calcium carbonate, etc. These can be used alone or in combination of two or more. Among them, from the viewpoint of improving durability, preferably carbon black, silica, more preferably carbon black.

[0066] Examples of carbon black include various grades of carbon black such as SAF grade, ISAF grade, HAF grade, MAF grade, FEF grade, GPF grade, SRF grade, FT grade, and MT grade. These may be used alone or in combination of two or more.

[0067] From the viewpoint of achieving both reversion resistance and durability, the BET specific surface area of ​​carbon black is preferably 10 to 150 m 2 / g, more preferably 15 to 100 m 2 / g, and more preferably 20 to 76 m 2 / g, particularly preferably 25 to 65 m 2 / g.

[0068] In addition, the BET specific surface area of ​​carbon black can be measured, for example, as follows: after degassing the sample at 200°C for 15 minutes, a mixed gas (N2: 70%, He: 30%) is used as the adsorption gas, and the measurement is performed using a BET specific surface area measuring device (manufactured by Micro Data, 4232-II).

[0069] From the viewpoint of both resistance to reversion and durability, the iodine adsorption of carbon black is preferably 10 to 150 mg / g, more preferably 10 to 75 mg / g, and still more preferably 20 to 65 mg / g. In addition, the DBP (dibutyl phthalate) absorption of carbon black is preferably 20 to 180 mL / 100 g, and more preferably 20 to 150 mL / 100 g.

[0070] The iodine adsorption of carbon black is a value measured in accordance with JIS K 6217-1 (A method), and the DBP absorption of carbon black is a value measured in accordance with JIS K 6217-4.

[0071] Examples of silica include wet silica, dry silica, colloidal silica, etc. These may be used alone or in combination of two or more.

[0072] From the viewpoint of achieving both reversion resistance and durability, the BET specific surface area of ​​silica is preferably 30 to 320 m 2 / g, more preferably 50 to 230 m 2 / g.

[0073] The BET specific surface area of ​​silica can be measured, for example, by degassing the sample at 200°C for 15 minutes and then using a mixed gas (N2: 70%, He: 30%) as adsorption gas using a BET specific surface area measuring device (manufactured by MicroData, 4232-II).

[0074] From the viewpoint of achieving both reversion resistance and durability, the DBA (di-n-butylamine) adsorption amount of silica is preferably 20 to 100 mmol / kg, for example. The DBA adsorption amount represents the amount of DBA adsorbed on the hydroxyl groups on the surface of silica, and is expressed as mmol of DBA adsorbed on 1 kg of silica.

[0075] From the viewpoint of achieving both reversion resistance and durability, the content of the (E) inorganic filler is preferably 10 to 90 parts by mass, more preferably 20 to 80 parts by mass, and even more preferably 40 to 70 parts by mass based on 100 parts by mass of the (A) diene rubber.

[0076] [Other ingredients]

[0077] The vibration-proof rubber composition may arbitrarily contain a vulcanization accelerator, a vulcanization aid, an antioxidant, a process oil, a silane coupling agent, and the like as components other than the components (A) to (E).

[0078] Examples of the vulcanization accelerator include various vulcanization accelerators such as thiuram-based, guanidine-based, and thiazole-based vulcanization accelerators, which may be used alone or in combination of two or more.

[0079] Examples of the thiuram vulcanization accelerator include tetramethylthiuram disulfide (TMTD), tetraethylthiuram disulfide (TETD), tetrabutylthiuram disulfide (TBTD), tetra(2-ethylhexyl)thiuram disulfide (TOT), and tetrabenzylthiuram disulfide (TBzTD). Among them, tetrabutylthiuram disulfide (TBTD) is preferred from the viewpoint of dispersibility. The content of the thiuram vulcanization accelerator is, for example, preferably 0.1 to 0.5 parts by mass, and more preferably 0.2 to 0.4 parts by mass, relative to 100 parts by mass of the diene rubber (A).

[0080] In other embodiments of the present invention, the thiuram vulcanization accelerator may be substantially not contained. For example, in applications where durability is relatively important (e.g., for suspension bushings), the content of the thiuram vulcanization accelerator may be less than 0.1 parts by mass, further less than 0.05 parts by mass, and particularly 0 parts by mass, relative to 100 parts by mass of the diene rubber (A).

[0081] Examples of the guanidine-based vulcanization accelerator include N,N′-diphenylthiourea, trimethylthiourea, N,N′-diethylthiourea, and N,N′-dibutylthiourea.

[0082] Examples of the thiazole vulcanization accelerator include dibenzothiazyl disulfide (MBTS), 2-mercaptobenzothiazole (MBT), 2-mercaptobenzothiazole sodium salt (NaMBT), and 2-mercaptobenzothiazole zinc salt (ZnMBT).

[0083] Examples of the vulcanizing aid include zinc oxide (ZnO), stearic acid, magnesium oxide, etc. These can be used alone or in combination of two or more. The content of the vulcanizing aid is preferably 0.1 to 10 parts by mass, more preferably 0.3 to 8 parts by mass, and even more preferably 1 to 6 parts by mass relative to 100 parts by mass of the diene rubber (A).

[0084] As the anti-aging agent, for example, carbamate anti-aging agents, phenylenediamine anti-aging agents, phenol anti-aging agents, diphenylamine anti-aging agents, quinoline anti-aging agents, imidazole anti-aging agents, waxes, etc. can be listed. They can be used alone or in combination of two or more. The content of the anti-aging agent is preferably 0.3 to 15 parts by mass, more preferably 0.5 to 10 parts by mass, and particularly preferably 1 to 8 parts by mass relative to 100 parts by mass of the diene rubber (A).

[0085] As process oil, for example, cycloparaffin oil, paraffin oil, aromatic oil, etc. can be cited. These can be used alone or in combination of two or more. The content of the process oil is preferably 1 to 30 parts by mass, more preferably 2 to 20 parts by mass, and even more preferably 3 to 15 parts by mass relative to 100 parts by mass of the diene rubber (A).

[0086] As the silane coupling agent, for example, mercapto-based silane coupling agents, sulfide-based silane coupling agents, amine-based silane coupling agents, epoxy-based silane coupling agents, vinyl-based silane coupling agents, etc. can be cited. They can be used alone or in combination of two or more. The content of the silane coupling agent is preferably 0.1 to 10 parts by mass, more preferably 0.3 to 8 parts by mass, relative to 100 parts by mass of the diene rubber (A).

[0087] [Method for preparing anti-vibration rubber composition and method for producing anti-vibration rubber member]

[0088] The vibration-proof rubber composition can be prepared by using the components (A) to (E) in a specific ratio, and further using the above-mentioned other components as needed, and kneading them using a kneading machine such as a kneader, a Banbury mixer, an open roll, a twin-screw mixer, etc. In addition, the vibration-proof rubber composition can be formed into a vibration-proof rubber member (vulcanized body) by vulcanizing at a high temperature (150 to 170° C.) for 5 to 30 minutes.

[0089] [Application of vibration-proof rubber components]

[0090] The anti-vibration rubber component composed of the vulcanized body of the anti-vibration rubber composition can improve the resistance to vulcanization reversion while suppressing the decrease in durability, so it can exert excellent performance as a material of anti-vibration rubber. For example, it can be suitably used as a component of an engine mount, a stabilizer bushing, a suspension bushing, a motor mount, a subframe mount, etc. used in vehicles such as automobiles [including electric vehicles (EV), fuel cell vehicles (FCV), plug-in hybrid vehicles (PHV), hybrid vehicles (HV), etc.].

[0091] Furthermore, it can also be used for vibration damping devices and seismic isolation devices such as vibration damping walls and vibration damping dampers for buildings in the construction / housing field, and vibration damping devices.

[0092] Example

[0093] Examples of the present invention and comparative examples are described below. However, the present invention is not limited to these examples. First, the following raw materials are prepared.

[0094] 〔Natural rubber (NR)〕

[0095] 〔Bismaleimide compounds〕

[0096] Sumifine BM manufactured by Sumika Chemtex

[0097] (N,N'-m-phenylene bismaleimide)

[0098] [Sulfenamide-based vulcanization accelerator]

[0099] ACCCEL CZ, a sulfenamide-based vulcanization accelerator manufactured by Kawaguchi Chemical Industry Co., Ltd.

[0100] (N-cyclohexyl-2-benzothiazolesulfenamide)

[0101] 〔Sulfur vulcanizing agent〕

[0102] Karuizawa Smelter Co., Ltd. produces sulfur

[0103] 〔Inorganic fillers〕

[0104] SEASTSO manufactured by Tokai Carbon

[0105] (FEF grade carbon black, BET specific surface area 42m 2 / g, DBP oil absorption: 115mL / 100g, iodine adsorption: 44mg / g)

[0106] 〔Zinc Oxide〕

[0107] Sakai Chemical Industry Co., Ltd. manufactures zinc oxide, type 2

[0108] 〔Stearic acid〕

[0109] NOF Corporation's beaded stearic acid SAKURA

[0110] 〔Anti-aging agent〕

[0111] Antigene 6C manufactured by Sumitomo Chemical

[0112] 〔Operating oil〕

[0113] SUNTHENE410 manufactured by Japan Sun Oil Company

[0114] [Examples 1 to 9, Comparative Examples 1 to 6]

[0115] Next, the above raw materials were blended and kneaded in the ratio shown in Table 1 to prepare a vibration-proof rubber composition. The above kneading was performed as follows: the raw materials other than the sulfur-based vulcanizing agent and the sulfenamide-based vulcanization accelerator were kneaded at 140° C. for 5 minutes using a Banbury mixer, and then the sulfur-based vulcanizing agent and the sulfenamide-based vulcanization accelerator were blended and kneaded at 60° C. for 5 minutes using an open roll.

[0116] Using the vibration-proof rubber compositions of Examples and Comparative Examples obtained above, various properties were evaluated according to the following criteria.

[0117] <Reversion resistance evaluation test>

[0118] For each anti-vibration rubber composition, a vulcanization test was carried out at 170°C using a vibration type vulcanization tester (rheometer tester), and the maximum elastic torque (MH) and the torque (ML) after 30 seconds to 5 minutes from reaching the maximum elastic torque (MH) were measured, and the vulcanization reversion rate (%) was calculated using the following formula.

[0119] (Formula) Sulfurization reversion rate (%) = [(MH-ML) / MH] × 100

[0120] The index conversion value of the reversion rate (%) in each example and comparative example was determined when the reversion rate (%) in Example 1 was 100, and the evaluation was performed according to the following criteria. The results are shown in Table 1.

[0121] [Evaluation criteria]

[0122] ◎(Excellent): 100 or less

[0123] ○ (very good): greater than 100 and less than 110

[0124] ×(difference): greater than 110

[0125] <Durability Evaluation Test>

[0126] Each vibration-proof rubber composition was press-formed (vulcanized) at 150° C. for 20 minutes to prepare a rubber sheet with a thickness of 2 mm. A JIS No. 3 dumbbell was punched out from the rubber sheet, and a dumbbell fatigue test (tensile test) was performed using the dumbbell in accordance with JIS K6260, and the number of tensile tests at break (number of times at break) was measured.

[0127] The index conversion value of the number of times of breaking in each example and comparative example was determined when the number of times of breaking in Example 1 was 100, and evaluation was performed according to the following criteria. The results are shown in Table 1.

[0128] [Evaluation criteria]

[0129] ◎(Excellent): 100 or more

[0130] ○ (very good): 75 or more and less than 100

[0131] ×(difference): less than 75

[0132] Table 1

[0133]

[0134] The results in Table 1 show that the vibration-proof rubber compositions or vulcanized products of the examples of the present invention are excellent in both reversion resistance and durability. That is, it is confirmed that the present invention can suppress reversion and also suppress a decrease in durability.

[0135] On the other hand, in the comparative examples that did not satisfy the requirements of the present invention, it was confirmed that the reversion resistance and durability were insufficient.

[0136] Although specific aspects of the present invention are shown in the above-mentioned embodiments, the above-mentioned embodiments are merely examples and are not to be interpreted as limiting. Various modifications obvious to those skilled in the art are intended to be included within the scope of the present invention.

[0137] Industrial Applicability

[0138] The anti-vibration rubber component formed from the vulcanized product of the anti-vibration rubber composition can improve the anti-vulcanization reversion resistance while suppressing the decrease in durability, and thus can exhibit excellent performance as a material for anti-vibration rubber. For example, it can be used as a component of an engine mount, a stabilizer bushing, a suspension bushing, a motor mount, a subframe mount, etc. used in a vehicle such as an automobile.

Claims

1. A vibration-proof rubber composition comprising the following components (A) to (E), It is characterized in that With respect to 100 parts by mass of the component (A), the content of the component (B) is 0.6 to 5.5 parts by mass, the content of the component (C) is 0.45 to 3.5 parts by mass, the content of the component (D) is 0.25 to 5.5 parts by mass, and the mass ratio of the component (C) to the component (D) [(C) / (D)] is 0.15 to 5.

0. (A) diene rubber, (B) a bismaleimide compound, (C) sulfenamide-based vulcanization accelerators, (D) sulfur-based vulcanizing agent, (E) Inorganic filler.

2. The anti-vibration rubber composition according to claim 1, in, The content of the sulfur-based vulcanizing agent (D) is 0.5 to 5.5 parts by mass.

3. The anti-vibration rubber composition according to claim 1 or 2, in, The mass ratio of the (C) sulfenamide vulcanization accelerator to the (D) sulfur vulcanizing agent [(C) / (D)] is 0.15 to 1.

35.

4. The anti-vibration rubber composition according to claim 1 or 2, in, The mass ratio of the (B) bismaleimide compound to the (C) sulfenamide vulcanization accelerator [(B) / (C)] is 0.4 to 5.

5.

5. The anti-vibration rubber composition according to claim 1 or 2, in, The (B) bismaleimide compound contains N,N'-m-phenylenebismaleimide.

6. The anti-vibration rubber composition according to claim 1 or 2, in, The (C) sulfenamide-based vulcanization accelerator contains at least one selected from the group consisting of N-cyclohexyl-2-benzothiazolesulfenamide and N-oxydiethylene-2-benzothiazolesulfenamide.

7. The anti-vibration rubber composition according to claim 1 or 2, in, The (E) inorganic filler contains at least one selected from the group consisting of carbon black and silica.

8. The anti-vibration rubber composition according to claim 1 or 2, in, Contains BET specific surface area of ​​10 to 150 m 2 / g of carbon black as the (E) inorganic filler.

9. The anti-vibration rubber composition according to claim 1 or 2, in, The (E) inorganic filler contains carbon black having an iodine adsorption amount of 10 to 150 mg / g.

10. The anti-vibration rubber composition according to claim 1 or 2, in, The anti-vibration rubber composition further contains a thiuram-based vulcanization accelerator.

11. A vibration-proof rubber component, in, The vibration-proof rubber member is formed of a vulcanized body of the vibration-proof rubber composition according to claim 1 or 2.

12. The vibration-proof rubber member according to claim 11, in, The anti-vibration rubber member is an anti-vibration rubber member for a vehicle.

13. The vibration-proof rubber member according to claim 12, in, The vibration-proof rubber member is a vibration-proof rubber member used as a component of an engine mount, a stabilizer bushing, or a suspension bushing.

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