JP7285258B2 - Anti-vibration rubber composition, method for producing the same, and anti-vibration rubber member - Google Patents

Description

TECHNICAL FIELD The present invention relates to an anti-vibration rubber composition used for anti-vibration applications in vehicles such as automobiles and trains, a method for producing the same, and an anti-vibration rubber member.

In the technical field of anti-vibration rubber, high durability, suppression of increase in loss factor tan δ (loss factor), reduction of dynamic ratio (dynamic ratio [dynamic spring constant (Kd) / static spring constant (Ks)] value ) is required. It is generally said that the content, particle size, dispersibility, interaction with the polymer, and the like of the filler compounded in the anti-vibration rubber composition greatly contribute to the control factors for realizing these requirements.
As the filler, carbon black, silica, etc. are usually used because of their high performance as a reinforcing material (see, for example, Patent Documents 1 to 3).

JP 2018-95810 A JP 2017-119873 A JP 2016-124880 A

However, in the technical field of anti-vibration rubber, it is said that it is difficult to achieve both high durability and low dynamic magnification of anti-vibration rubber with the above-mentioned filler. has been considered in the past.

Normally, in order to realize high durability of anti-vibration rubber, it is necessary to use a fine filler, that is, a filler with a small particle size, which is a reinforcing material.
However, when the particle size of the filler is small, the surface area of the filler increases, so the friction between the fillers and the friction between the filler and the polymer increase, and as a result, the dynamic magnification of the anti-vibration rubber increases. In addition, when the particle size of the filler is small, the dispersibility of the filler deteriorates, and filler agglomerates are likely to occur. These agglomerates increase the loss factor, leading to an increase in the dynamic magnification of the anti-vibration rubber. There is also
Conversely, if the filler particle size is large, it is possible to suppress the increase in the loss factor of the anti-vibration rubber and lower the dynamic magnification, but if the filler particle size is large, it tends to become the starting point of rubber failure, resulting in the following: There arises a problem that the durability of the anti-vibration rubber deteriorates.

The present invention has been made in view of such circumstances, and provides a vibration-isolating rubber composition capable of achieving high durability, suppression of loss factor increase, and low dynamic magnification at a high level, and a method for producing the same. and anti-vibration rubber members.

［６］更にシランカップリング剤（Ｄ）を含有する、［１］～［５］のいずれかに記載の防振ゴム組成物。
［７］上記（Ｄ）成分が、メルカプト系シランカップリング剤およびスルフィド系シランカップリング剤の少なくとも一方である、［６］記載の防振ゴム組成物。
［８］上記（Ａ）成分１００重量部に対する上記（Ｄ）成分の含有量が０．５～２０重量部の範囲である、［６］または［７］に記載の防振ゴム組成物。
［９］更にカーボンブラック（Ｅ）を含有する、［１］～［８］のいずれかに記載の防振ゴム組成物。
［１０］上記（Ｅ）成分が、ＢＥＴ比表面積５～２００ｍ²／ｇのカーボンブラックである、［９］に記載の防振ゴム組成物。
［１１］上記（Ａ）成分１００重量部に対する上記（Ｅ）成分の含有量が１～１０重量部の範囲である、［９］または［１０］に記載の防振ゴム組成物。
［１２］上記［６］～［１１］のいずれかに記載の防振ゴム組成物の製造方法であって、上記防振ゴム組成物の材料である上記（Ａ）～（Ｄ）成分のうち、（Ａ）～（Ｃ）成分を予め混合した後、（Ｄ）成分を添加して混合する工程を備えていることを特徴とする防振ゴム組成物の製造方法。
［１３］上記［１］～［１１］のいずれかに記載の防振ゴム組成物の加硫体からなることを特徴とする防振ゴム部材。The gist of the present invention is the following [1] to [13].
[1] A vibration-insulating rubber composition characterized by containing the following components (B) and (C) together with the following component (A).
(A) A diene rubber containing natural rubber as a main component.
(B) Silica.
(C) At least one of (C1) and (C2) below.
(C1) A compound having an NH ₂ group and an SSO ₃ H group and having a molecular weight of 143-241.
(C2) A compound having an NH ₂ group and an ene structure and having a molecular weight of 228-480.
[2] The anti-vibration rubber composition according to [1], wherein the content of component (C) is in the range of 0.01 to 10 parts by weight per 100 parts by weight of component (A).
[3] The anti-vibration rubber composition according to [1] or [2], wherein the silica (B) has a BET specific surface area of 30 to 320 m ² /g.
[4] The anti-vibration rubber composition according to any one of [1] to [3], wherein the content of component (B) is in the range of 5 to 100 parts by weight per 100 parts by weight of component (A).
[5] The component (C) is S-(3-aminopropyl) thiosulfate represented by the following chemical formula (1) and (2Z)-4-[(4) represented by the following chemical formula (2). The anti-vibration rubber composition according to any one of [1] to [4], which is at least one of sodium -aminophenyl)amino]-4-oxo-2-butenoate.

[6] The anti-vibration rubber composition according to any one of [1] to [5], further containing a silane coupling agent (D).
[7] The anti-vibration rubber composition according to [6], wherein the component (D) is at least one of a mercapto-based silane coupling agent and a sulfide-based silane coupling agent.
[8] The anti-vibration rubber composition according to [6] or [7], wherein the content of component (D) is in the range of 0.5 to 20 parts by weight per 100 parts by weight of component (A).
[9] The anti-vibration rubber composition according to any one of [1] to [8], further containing carbon black (E).
[10] The anti-vibration rubber composition according to [9], wherein the component (E) is carbon black having a BET specific surface area of 5 to 200 m ² /g.
[11] The anti-vibration rubber composition according to [9] or [10], wherein the content of component (E) is in the range of 1 to 10 parts by weight per 100 parts by weight of component (A).
[12] A method for producing the anti-vibration rubber composition according to any one of [6] to [11] above, wherein A method for producing a vibration-insulating rubber composition, comprising a step of pre-mixing components (A) to (C), and then adding and mixing component (D).
[13] A vibration-isolating rubber member comprising a vulcanized body of the vibration-isolating rubber composition according to any one of [1] to [11] above.

That is, the present inventors have made earnest studies to solve the above problems. In the process of this research, we adopted silica as a filler for diene rubber, the main component of which is natural rubber, which is the polymer of anti-vibration rubber compositions. We studied how to combine dynamic magnification at a high level. As a result of intensive research, it was found that by adding the compounds shown in (C1) and (C2) above to the anti-vibration rubber composition, high durability, suppression of loss factor increase, and low dynamic magnification can be achieved. I found out that I can make both at the same level.
Although the reason why such a result was obtained is not clear, it is considered as follows. That is, the compounds shown in (C1) and (C2) have relatively large molecular weights as additives, and their SSO ₃ H group and ene structure (-C=C-) are equivalent to the diene rubber (A). Since it reacts with and interacts with the ene structure of , it can be expected to have an affinity with diene-based rubber polymers whose main component is natural rubber. In addition, the NH ₂ group of the above compound interacts with the hydroxyl group of silica and serves to dissolve aggregated silica, thereby improving the dispersibility of silica. As a result of these actions, it is considered that the low dynamic magnification can be realized while maintaining the high durability of the anti-vibration rubber and suppressing the increase of the loss factor.

Thus, the anti-vibration rubber composition of the present invention contains (C) at least one of (C1) and (C2) together with (A) a diene rubber containing natural rubber as a main component and (B) silica. do. Therefore, high durability, suppression of increase in loss factor, and low dynamic magnification can all be achieved at a high level.

Next, an embodiment of the present invention will be described in detail. However, the present invention is not limited to this embodiment.

As described above, the anti-vibration rubber composition of the present invention contains the following components (B) and (C) together with the following component (A).
(A) A diene rubber containing natural rubber as a main component.
(B) Silica.
(C) At least one of (C1) and (C2) below.
(C1) A compound having an NH ₂ group and an SSO ₃ H group and having a molecular weight of 143-241.
(C2) A compound having an NH ₂ group and an ene structure and having a molecular weight of 228-480.

The constituent materials of the anti-vibration rubber composition of the present invention are described in detail below.

[Diene rubber (A)]
As described above, a diene rubber containing natural rubber as a main component is used as the diene rubber (A). Here, the term "main component" means that the diene rubber (A) is 50% by weight or more of natural rubber, and is intended to include the case where the diene rubber (A) consists only of natural rubber. In this way, by using natural rubber as a main component, the strength and dynamic magnification can be reduced.
Examples of the diene rubber used in combination with the natural rubber as necessary include 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) and the like. These are used alone or in combination of two or more.

[Silica (B)]
Next, as the silica (B), for example, wet silica, dry silica, colloidal silica, and the like are used. And these are used individually or in combination of 2 or more types.

Further, from the viewpoint of achieving both high durability, suppression of loss factor increase, and low dynamic magnification, the BET specific surface area of the silica (B) is preferably 30 to 320 m ² /g, more preferably. is between 50 and 230 m ² /g.
In addition, the BET specific surface area of the silica (B) is obtained by, for example, degassing the sample at 200 ° C. for 15 minutes, using a mixed gas (N ₂ : 70%, He: 30%) as an adsorption gas, BET ratio It can be measured with a surface area measuring device (4232-II, manufactured by Microdata).

Further, from the viewpoint of achieving both high durability, suppression of loss factor increase, and low dynamic ratio, the content of the silica (B) is 5 to 100 parts per 100 parts by weight of the diene rubber (A). It is preferably parts by weight, more preferably 20 to 60 parts by weight.

[Specific compound (C)]
As described above, at least one of the following (C1) and (C2) is used as the specific compound (C). That is, the compounds belonging to (C1) and (C2) are used alone or in combination of two or more.
(C1) A compound having an NH ₂ group and an SSO ₃ H group and having a molecular weight of 143-241.
(C2) A compound having an NH ₂ group and an ene structure and having a molecular weight of 228-480.

The "ene structure" in (C2) above is a carbon-carbon double bond site (-C=C-), and this carbon-carbon double bond site is the molecular chain of the compound shown in (C2). It may be terminal or internal to the molecular chain.

Further, as described above, the molecular weight of the compound represented by (C1) is in the range of 143-241, preferably in the range of 157-185. Further, as described above, the molecular weight of the compound represented by (C2) is in the range of 228-480, preferably in the range of 228-312. That is, within such a range, the affinity with the diene rubber (A) is more excellent. The above molecular weight is a calculated value or a catalog value calculated from the molecular structure of the above compound.

Among the specific compounds (C) used in the present invention as shown above, S-(3-aminopropyl) thiosulfate represented by the following chemical formula (1) and the following Sodium (2Z)-4-[(4-aminophenyl)amino]-4-oxo-2-butenoate represented by the chemical formula (2) has even higher durability, suppression of loss factor increase, and low motion. It is preferable from the viewpoint of achieving both magnification.

The content of these specific compounds (C) is 0.01 per 100 parts by weight of the diene rubber (A) from the viewpoint of achieving both high durability, suppression of loss factor increase, and low dynamic ratio. It is preferably 10 parts by weight, more preferably 0.1 to 5 parts by weight.

Here, the anti-vibration rubber composition of the present invention contains the components (A) to (C) as essential components, but may also contain the following components as necessary.

[Silane coupling agent (D)]
When the silane coupling agent (D) is contained in addition to the above components (A) to (C), the silica (B) and the diene rubber (A) are bonded via the silane coupling agent (D) to further prevent This is preferable because the durability of the vibration rubber can be improved.
Examples of the silane coupling agent (D) include mercapto-based silane coupling agents, sulfide-based silane coupling agents, amine-based silane coupling agents, epoxy-based silane coupling agents, and vinyl-based silane coupling agents. They are used singly or in combination of two or more. Among them, it is preferable that the silane coupling agent (D) is a mercapto-based silane coupling agent or a sulfide-based silane coupling agent, because the crosslink density is increased and the dynamic magnification and the durability are particularly effective.

Examples of the mercapto-based silane coupling agent include 3-mercaptopropyltrimethoxysilane and 3-mercaptopropyltriethoxysilane. These are used alone or in combination of two or more.

Examples of the sulfide-based silane coupling agent include bis-(3-(triethoxysilyl)-propyl)-disulfide, bis(3-triethoxysilylpropyl) trisulfide, bis-(3-(triethoxysilyl) -propyl)-tetrasulfide, bis(3-trimethoxysilylpropyl) disulfide, bis(2-triethoxysilylethyl) tetrasulfide, bis(2-trimethoxysilylethyl) tetrasulfide, bis(3-triethoxysilylpropyl) ) disulfide, 3-trimethoxysilylpropyl-N,N-dimethylthiocarbamoyl tetrasulfide, 3-triethoxysilylpropyl-N,N-dimethylthiocarbamoyl tetrasulfide, 2-triethoxysilylethyl-N,N-dimethylthio Carbamoyl tetrasulfide, 2-trimethoxysilylethyl-N,N-dimethylthiocarbamoyl tetrasulfide, 3-trimethoxysilylpropyl benzothiazolyl tetrasulfide, 3-triethoxysilylpropyl benzothiazole tetrasulfide, 3-triethoxysilyl Propyl methacrylate monosulfide, 3-trimethoxysilylpropyl methacrylate monosulfide and the like. These are used alone or in combination of two or more.

Examples of the amine-based silane coupling agent include 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2- aminoethyl)-3-aminopropylmethyldimethoxysilane, 3-(N-phenyl)aminopropyltrimethoxysilane and the like. These are used alone or in combination of two or more.

Examples of the epoxy-based silane coupling agent include 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3- glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, and the like. These are used alone or in combination of two or more.

Examples of the vinyl-based silane coupling agent include vinyltriethoxysilane, vinyltrimethoxysilane, vinyl-tris(β-methoxyethoxy)silane, vinyldimethylchlorosilane, vinyltrichlorosilane, vinyltriisopropoxysilane, and vinyl-tris. (2-Methoxyethoxy)silane and the like can be mentioned. These are used alone or in combination of two or more.

The content of these silane coupling agents (D) is preferably 0.5 to 20 parts by weight with respect to 100 parts by weight of the diene rubber (A) because of its excellent low dynamic magnification and durability. Preferably, it is 1 to 10 parts by weight.

[Carbon black (E)]
In addition to the above components (A) to (C), it is preferable to contain carbon black (E) because deterioration by ultraviolet rays can be prevented.
As the carbon black (E), 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 are used. These are used alone or in combination of two or more.

From the viewpoint of durability and low dynamic magnification, the carbon black (E) is preferably carbon black having a BET specific surface area of 5 to 200 m ² /g. Carbon black with a BET specific surface area of 20 to 110 m ² /g is more preferred.
In addition, the BET specific surface area of the carbon black (E) is obtained by, for example, degassing the sample at 200 ° C. for 15 minutes, using a mixed gas (N ₂ : 70%, He: 30%) as an adsorption gas, BET It can be measured with a specific surface area measuring device (manufactured by Microdata, 4232-II).

The content of these carbon blacks (E) should be in the range of 1 to 10 parts by weight with respect to 100 parts by weight of the diene rubber (A) from the viewpoint of achieving both durability and low dynamic magnification. is preferred, more preferably 2 to 5 parts by weight.

In addition, in the anti-vibration rubber composition of the present invention, together with the essential components (A) to (C), the optional components (D) and (E), a vulcanizing agent, a vulcanizing agent, Vulcanization accelerators, vulcanization auxiliaries, anti-aging agents, process oils, etc., may be appropriately incorporated as required.

Examples of the vulcanizing agent include sulfur (powder sulfur, precipitated sulfur, insoluble sulfur), sulfur-containing compounds such as alkylphenol disulfide, and the like. These may be used alone or in combination of two or more.

The content of the vulcanizing agent is preferably in the range of 0.1 to 10 parts by weight, particularly preferably in the range of 0.3 to 5 parts by weight, per 100 parts by weight of the diene rubber (A). That is, if the content of the vulcanizing agent is too low, the cross-linking reactivity tends to be poor, and if the content of the vulcanizing agent is too high, rubber physical properties (strength at break, elongation at break) decrease. This is because there is a tendency to

Examples of the vulcanization accelerator include thiuram-based, sulfenamide-based, guanidine-based, thiazole-based, aldehyde-ammonia-based, aldehydeamine-based, and thiourea-based vulcanization accelerators. These may be used alone or in combination of two or more. Among these, a combination of a thiuram-based vulcanization accelerator and at least one vulcanization accelerator selected from sulfenamide-based, guanidine-based, and thiazole-based vulcanization accelerators is used because it provides excellent compression set. is preferred.

The content of the vulcanization accelerator is preferably in the range of 0.1 to 10 parts by weight, particularly preferably in the range of 0.3 to 5 parts by weight, based on 100 parts by weight of the diene rubber (A). be.

Examples of the thiuram-based vulcanization accelerator include tetramethylthiuram disulfide (TMTD), tetraethylthiuram disulfide (TETD), tetrabutylthiuram disulfide (TBTD), tetrakis(2-ethylhexyl)thiuram disulfide (TOT), and tetrabenzylthiuram. disulfide (TBzTD) and the like.

Examples of the sulfenamide-based vulcanization accelerator include N-oxydiethylene-2-benzothiazolylsulfenamide (NOBS), N-cyclohexyl-2-benzothiazolylsulfenamide (CBS), Nt -Butyl-2-benzothiazolesulfenamide (BBS), N,N'-dicyclohexyl-2-benzothiazolesulfenamide and the like. These are used alone or in combination of two or more.

Examples of the guanidine-based vulcanization accelerator include N,N'-diphenylthiourea, trimethylthiourea, N,N'-diethylthiourea, and N,N'-dibutylthiourea. These are used alone or in combination of two or more.

Examples of the thiazole-based vulcanization accelerator include dibenzothiazyl disulfide (MBTS), 2-mercaptobenzothiazole (MBT), 2-mercaptobenzothiazole sodium salt (NaMBT), and 2-mercaptobenzothiazole zinc salt (ZnMBT). etc. These are used alone or in combination of two or more. Among these, dibenzothiazyl disulfide (MBTS) and 2-mercaptobenzothiazole (MBT) are preferably used because of their excellent cross-linking reactivity.

Examples of the vulcanizing aid include zinc oxide (ZnO), stearic acid, magnesium oxide, and the like. These are used alone or in combination of two or more.

The content of the vulcanization aid is preferably in the range of 0.1 to 10 parts by weight, particularly preferably in the range of 0.3 to 7 parts by weight, with respect to 100 parts by weight of the diene rubber (A). be.

Examples of the anti-aging agent include carbamate-based anti-aging agents, phenylenediamine-based anti-aging agents, phenol-based anti-aging agents, diphenylamine-based anti-aging agents, quinoline-based anti-aging agents, imidazole-based anti-aging agents, and waxes. can give. These are used alone or in combination of two or more.

The content of the anti-aging agent is preferably in the range of 0.5 to 15 parts by weight, particularly preferably in the range of 1 to 10 parts by weight, per 100 parts by weight of the diene rubber (A).

Examples of the process oil include naphthenic oil, paraffinic oil, aromatic oil, and the like. These are used alone or in combination of two or more.

The content of the process oil is preferably in the range of 1 to 35 parts by weight, particularly preferably in the range of 3 to 30 parts by weight, per 100 parts by weight of the diene rubber (A).

[Method for preparing anti-vibration rubber composition]
Here, the anti-vibration rubber composition of the present invention uses the essential components (A) to (C) and, if necessary, the other materials listed above, and kneads, Banbury mixer, open It can be prepared by kneading using a kneader such as a roll or twin-screw stirrer.
Since the silane coupling agent (D) has the property of interacting more easily with the silica (B) than the specific compound (C), the silane coupling agent (D) is added to the material of the anti-vibration rubber composition. When used, the diene rubber (A), silica (B), and the specific compound (C) are mixed in advance, and then the silane coupling agent (D) is added and mixed to obtain silica (B). dispersion, etc., can be achieved more satisfactorily, and high durability, suppression of increase in loss factor, and reduction in dynamic magnification can be achieved at a higher level.

The anti-vibration rubber composition of the present invention thus obtained is vulcanized at a high temperature (150 to 170° C.) for 5 to 30 minutes to form a rubber anti-vibration member (vulcanized body). A vibration-isolating rubber member comprising a vulcanized body of the vibration-isolating rubber composition of the present invention is preferably used as a vibration-isolating material for engine mounts, stabilizer bushes, suspension bushes, etc. used in vehicles such as gasoline-powered vehicles. In addition, vibration control (vibration control) such as vibration control dampers for hard disks of computers, vibration control dampers for general home appliances such as washing machines, vibration control walls for construction and housing, and vibration control (vibration control) dampers It can also be used for equipment and seismic isolation applications.

Next, examples will be described together with comparative examples. However, the present invention is not limited to these examples.

First, prior to Examples and Comparative Examples, the following materials were prepared. The BET specific surface areas of carbon black and silica were measured by the BET specific surface area measuring device (manufactured by Microdata, 4232-II) according to the above method.

[Natural rubber (NR)]
RSS#3

[Zinc oxide]
Manufactured by Sakai Chemical Industry Co., Ltd., two types of zinc oxide

〔stearic acid〕
Made by Kao Corporation, Lunar S30

[Anti-aging agent]
Ozonon 6C manufactured by Seiko Chemical Co., Ltd.

[Silica (i)]
Nipseal VN3 (BET specific surface area: 180 to 230 m ² /g) manufactured by Tosoh Silica Co., Ltd.

[Silica (ii)]
Nipseal ER manufactured by Tosoh Silica Corporation (BET specific surface area 70 to 120 m ² /g)

[Silica (iii)]
Nipseal EL (BET specific surface area: 50 m ² /g) manufactured by Tosoh Silica Co., Ltd.

〔Carbon black〕
Show Black N330 (BET specific surface area: 75 m ² /g) manufactured by Cabot Corporation

〔Silane coupling agent〕
Sulfide-based silane coupling agent (manufactured by EVONIK, Si-69)

[Compound (i)]
The compound represented by the chemical formula (1) (SUMILINK100 manufactured by Sumitomo Chemical Co., Ltd.)

[Compound (ii)]
The compound represented by the chemical formula (2) (SUMILINK200 manufactured by Sumitomo Chemical Co., Ltd.)

[Vulcanization accelerator]
Sulfenamide-based vulcanization accelerator (Suncellar CZ manufactured by Sanshin Chemical Co., Ltd.)

[Sulfur (vulcanizing agent)]
Manufactured by Karuizawa Smelter & Refinery

[Examples 1 to 10, Comparative Example 1]
A vibration-insulating rubber composition was prepared by blending and kneading the above materials in the proportions shown in Table 1 below. In the kneading, first, materials other than the vulcanizing agent and the vulcanization accelerator (excluding the silane coupling agent) are kneaded at 140° C. for 5 minutes using a Banbury mixer, and then the vulcanizing agent and vulcanization are mixed. An accelerator was blended (a silane coupling agent was also blended in the case of using a silane coupling agent), and kneaded at 60°C for 5 minutes using an open roll.

Using the anti-vibration rubber compositions of Examples and Comparative Examples thus obtained, each characteristic was evaluated according to the following criteria. The results are also shown in Table 1 below.

<Attenuation>
Each anti-vibration rubber composition was press-molded (vulcanized) under conditions of 160° C. for 30 minutes to prepare a test piece. Next, the loss factor (tan δ) at a frequency of 15 Hz was obtained according to JIS K 6385.
In Table 1 below, when the measured value of tan δ in Comparative Example 1 was set to 100, the measured value of tan δ in each example was converted into an index.
Then, those having a tan δ value lower than the tan δ value of Comparative Example 1 were evaluated as “good”, and those having a tan δ value exceeding the tan δ value of Comparative Example 1 were evaluated as “x”.

<Dynamic magnification>
Each anti-vibration rubber composition was press-molded (vulcanized) under conditions of 160° C. for 30 minutes to prepare a test piece. The dynamic spring constant (Kd100) and static spring constant (Ks) of this test piece were measured according to JIS K 6394, respectively. Based on the value, the dynamic magnification (Kd100/Ks) was calculated.
In Table 1 below, the measured value of the dynamic magnification in each example is indexed when the measured value of the dynamic magnification (Kd100/Ks) in Comparative Example 1 is set to 100.
Then, when the value of the dynamic magnification is lower than the value of the dynamic magnification of Comparative Example 1, it is evaluated as "good", and when the value of the dynamic magnification exceeds the value of the dynamic magnification of Comparative Example 1, it is evaluated as "x".

<Durability>
Each anti-vibration rubber composition was press-molded (vulcanized) under conditions of 160° C. for 30 minutes to prepare a rubber sheet with a thickness of 2 mm. A JIS No. 3 dumbbell was punched out from this rubber sheet, and a dumbbell fatigue test (extension test) was performed according to JIS K 6260 using this dumbbell. Then, the number of times of elongation at break (number of times at break) was measured.
In Table 1 below, when the measured value of the number of times at break in Comparative Example 1 is set to 100, the measured value of the number of times at break in each example is converted into an index.
Then, when the value of the number of times at break exceeded the value of the number of times at break of Comparative Example 1, it was evaluated as "good", and when the value of the number of times at break was less than the value of the number of times at break of Comparative Example 1, it was evaluated as "x".

From the results in Table 1 above, the vulcanized body of the vibration-isolating rubber composition of Example has a smaller tan δ value than the vulcanized body of the vibration-isolating rubber composition of Comparative Example 1, and the dynamic magnification (Kd100/Ks) is low, and the number of times at break is large, indicating high durability.

Although specific embodiments of the present invention have been described in the above examples, the above examples are merely illustrative and should not be construed as limiting. Various modifications apparent to those skilled in the art are intended to be within the scope of the invention.

The anti-vibration rubber composition of the present invention is preferably used as an anti-vibration material for engine mounts, stabilizer bushes, suspension bushes and the like used in vehicles such as gasoline automobiles. It can also be used for vibration control dampers for general home appliances such as washing machines, vibration control walls for buildings in the construction and housing fields, vibration control (vibration control) devices such as vibration control (vibration control) dampers, and seismic isolation devices. can.

Claims (9)

It contains the following components (B) , ( C) and (E) together with the following component (A), and the content of component (B) is 5 to 40 parts by weight per 100 parts by weight of component (A) The content of component (C) is in the range of 0.01 to 10 parts by weight per 100 parts by weight of component (A), and the content of component (E) is in the range of 1 to 10 parts by weight of component (A). An anti-vibration rubber composition characterized by being in the range of 10 parts by weight .
(A) A diene rubber containing natural rubber as a main component.
(B) Silica.
(C) At least one of (C1) and (C2) below.
(C1) A compound having an NH ₂ group and an SSO ₃ H group and having a molecular weight of 143-241.
(C2) A compound having an NH ₂ group and an ene structure and having a molecular weight of 228-480.
(E) Carbon black. 2. The vibration-insulating rubber composition according to claim 1 , wherein said silica (B) has a BET specific surface area in the range of 30 to 320 m ² /g. The component (C) is S-(3-aminopropyl) thiosulfate represented by the following chemical formula (1) and (2Z)-4-[(4-aminophenyl) represented by the following chemical formula (2). ) sodium amino]-4-oxo- 2- butenoate.

The anti-vibration rubber composition according to any one of claims 1 to 3 , further comprising a silane coupling agent (D). 5. The vibration-insulating rubber composition according to claim 4 , wherein the component (D) is at least one of a mercapto-based silane coupling agent and a sulfide-based silane coupling agent. 6. The anti-vibration rubber composition according to claim 4 , wherein the content of component (D) is in the range of 0.5 to 20 parts by weight per 100 parts by weight of component (A). The anti-vibration rubber composition according to any one of claims 1 to 6 , wherein the component (E) is carbon black having a BET specific surface area of 5 to 200 m ² /g. 7. The method for producing the vibration-isolating rubber composition according to any one of claims 4 to 6 , wherein (A) is selected from components (A) to (D), which are materials of the vibration-isolating rubber composition. A method for producing a vibration-insulating rubber composition, comprising a step of premixing component (C) and then adding and mixing component (D). A rubber vibration isolator member comprising a vulcanized body of the rubber vibration isolation composition according to any one of claims 1 to 8 .