JP2009256579A - Method for producing vibration-proof rubber composition and vibration-proof rubber composition produced by the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a vibration-proof rubber composition for satisfying both a low dynamic spring characteristics (low dynamic magnification) and a high attenuation. <P>SOLUTION: The method for producing a vibration-proof rubber composition comprises kneading a halogenated butyl rubber with a silica-based filler and a silane coupling to prepare a master batch, kneading the master batch with a diene-based rubber and dispersing the silica-based filler into the halogenated butyl rubber. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for producing a vibration-proof rubber composition and a vibration-proof rubber composition obtained thereby.

  Conventionally, an anti-vibration rubber interposed between two members constituting a vibration transmission system and anti-vibrating and connecting the two members has been widely used in various fields. For example, in the automobile field, an engine mount is used. , Body mounts, member mounts, suspension bushings, etc. Such anti-vibration rubber for automobiles such as engine mounts is normally used in a transmission system for a plurality of types of vibrations having different frequencies and the like, and normally exhibits effective anti-vibration characteristics according to applied vibrations. Is required. Specifically, in an anti-vibration rubber for automobiles, in general, when vibration in a relatively high frequency region of 100 Hz or more is applied, low dynamic spring characteristics (low dynamic magnification) are required. When a low frequency vibration of about 20 Hz is applied, high damping characteristics are required.

  In this type of anti-vibration rubber, the spring characteristics are expressed by the bonding, restraint or entanglement between polymer molecules constituting the rubber composition serving as the anti-vibration rubber, or a reinforcing agent contained in the polymer molecule and the rubber composition. It is based on the connection and restraint. On the other hand, the manifestation mechanism of the damping characteristics is based on friction between polymer molecules or between polymer molecules and a reinforcing agent such as carbon black. In general, when the damping characteristics are increased, the vibration characteristics of the anti-vibration rubber also increase, and conversely, when the low dynamic spring characteristics are realized, the damping characteristics of the anti-vibration rubber also decrease. It was. Therefore, the development of a vibration-proof rubber that can realize both the low dynamic spring characteristics and the high damping characteristics is a major issue.

In order to obtain a vibration-insulating rubber having such a vibration-damping property of low dynamic spring-high damping, for example, as a rubber material constituting the vibration-proof rubber, a natural rubber ( Various measures for improving the material such as reforming of the rubber material and improvement of the blending method thereof have been proposed, such as using NR) and adding carbon black thereto to achieve high attenuation. In addition, a rubber component obtained by blending natural rubber and butyl rubber, a hydrazine derivative, a large particle size / high structure carbon black as a filler, and an alkylphenol disulfide and sulfur as a crosslinking agent (vulcanizing agent) An anti-vibration rubber obtained by blending the above has also been proposed (for example, Patent Document 1).
JP 2006-143860 A

  However, according to the conventional method for producing an anti-vibration rubber composition, since carbon black is usually dispersed (localized) in natural rubber, it is not possible to achieve both low dynamic spring characteristics (low dynamic magnification) and high damping properties. It was enough.

  The present invention has been made in view of such circumstances, and a method for producing a vibration isolating rubber composition capable of achieving both low dynamic spring characteristics (low dynamic magnification) and high damping properties, and vibration isolation obtained thereby. The object is to provide a rubber composition.

  In order to achieve the above object, the present invention prepares a master batch by kneading a halogenated butyl rubber, a silica filler, and a silane coupling agent, and then kneading the master batch and a diene rubber. Thus, the first gist is a method for producing a vibration-insulating rubber composition in which the silica-based filler is dispersed in a halogenated butyl rubber. Moreover, this invention makes the 2nd summary the vibration-insulating rubber composition obtained by the said manufacturing method.

  The inventors of the present invention have made extensive studies in order to obtain an anti-vibration rubber composition capable of achieving both low dynamic spring characteristics (low dynamic magnification) and high damping properties. Focusing on halogenated butyl rubber, diene rubber, and silica filler, instead of kneading them at the same time, first kneaded halogenated butyl rubber, silica filler, and silane coupling agent. Thus, it was found that good results can be obtained by preparing a master batch (master batch method), and the present invention has been achieved. That is, in the present invention, when a master batch is prepared by kneading a halogenated butyl rubber, a silica-based filler, and a silane coupling agent, the silica-based filler and the coupling agent react during the kneading, and the silica-based The silica-based filler is almost dispersed (unevenly distributed) in the halogenated butyl rubber because the affinity between the filler and the halogenated butyl rubber is increased. As a result, the attenuation and physical properties of the halogenated butyl rubber are improved, and the silica filler is hardly dispersed in the diene rubber, so that the dynamic ratio of the diene rubber is increased by the dispersion of the silica filler. And low dynamic magnification of the diene rubber is maintained. Thereby, both low dynamic spring characteristics (low dynamic magnification) and high damping can be achieved.

  In the present invention, the low dynamic spring characteristic means that the value of the dynamic magnification (= Kd100 / Ks) which is the ratio of the dynamic spring constant (Kd100) and the static spring constant (Ks) at 100 Hz is small. In addition, the high damping characteristic means a value having a large loss coefficient (tan δ) at the time of vibration input at 15 Hz.

  As described above, the method for producing the vibration-proof rubber composition of the present invention does not involve kneading the halogenated butyl rubber, the diene rubber, and the silica filler at the same time. First, the halogenated butyl rubber and the silica filler are used. And a silane coupling agent are kneaded to prepare a master batch, and the master batch and a diene rubber are kneaded. Therefore, the silica filler is almost dispersed in the halogenated butyl rubber, so that the attenuation and physical properties of the halogenated butyl rubber are improved, and the silica filler is hardly dispersed in the diene rubber. Is prevented from increasing due to the dispersion of the silica filler, and the low dynamic ratio of the diene rubber is maintained. Thereby, both low dynamic spring characteristics (low dynamic magnification) and high damping can be achieved.

  When a master batch is prepared by kneading at a high temperature of 130 to 170 ° C., the silica filler and the coupling agent react to increase the affinity between the silica filler and the halogenated butyl rubber. The silica-based filler is more easily dispersed (distributed) in the inside, and further attenuates.

  Further, when the above-mentioned diene rubber added with carbon black is kneaded with the master batch or the master batch is prepared by adding carbon black, the attenuation becomes higher.

  Next, embodiments of the present invention will be described in detail.

  In the present invention, after preparing a master batch by kneading a halogenated butyl rubber, a silica-based filler, and a silane coupling agent, the master batch and a diene rubber are kneaded, and the silica-based filler Is a method for producing a vibration-proof rubber composition in which is dispersed in a halogenated butyl rubber.

  In the present invention, instead of kneading the halogenated butyl rubber, the diene rubber, and the silica filler at the same time, first, a master batch is prepared by kneading the halogenated butyl rubber and the silica filler ( Master batch method) After dispersing (unevenly distributed) silica-based filler in halogenated butyl rubber, the halogenated butyl rubber in which this silica-based filler is dispersed and diene rubber are kneaded. It is the biggest feature.

  Examples of the halogenated butyl rubber (halogenated IIR) include chlorinated butyl rubber and brominated butyl rubber. These may be used alone or in combination of two or more. Among these, chlorinated butyl rubber is preferable in terms of low dynamic magnification.

  The silica-based filler refers to a filler having silica as an active ingredient, and examples thereof include silica, clay, sericite, calcium silicate, and aluminum silicate. These may be used alone or in combination of two or more. Among these, silica is preferable from the viewpoint of reinforcing properties.

  The blending amount of the silica-based filler is preferably in the range of 5 to 100 parts, particularly preferably 10 to 60 parts with respect to 100 parts by weight of the halogenated butyl rubber (hereinafter abbreviated as “parts”) from the viewpoint of physical properties. It is a range.

  The silane coupling agent is used for the purpose of improving the affinity between the silica-based filler and the halogenated butyl rubber. A specific example of the silane coupling agent is Si69 manufactured by EVONIK DEGUSSA. In the case of using silica treated with a silane coupling agent whose surface is treated with a silane coupling agent as the silica-based filler, it is not necessary to add a silane coupling agent.

  The blending amount of the silane coupling agent is preferably in the range of 0.2 to 20 parts, particularly preferably in the range of 1 to 10 parts, with respect to 100 parts of the halogenated butyl rubber, from the viewpoint of affinity with the halogenated butyl rubber. It is.

  In the present invention, when preparing the masterbatch, in addition to the halogenated butyl rubber, the silica-based filler, and the silane coupling agent, carbon black, a hydrazide compound, a process oil, and the like are appropriately blended as necessary. There is no problem.

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

  In the present invention, two or more types of carbon blacks having different particle sizes may be blended in the master batch process.

  The average particle size of the carbon black having a small particle size is preferably in the range of 14 to 40 nm, particularly preferably in the range of 20 to 35 nm. The average particle size of the large particle size carbon black is preferably in the range of 41 to 125 nm, particularly preferably in the range of 60 to 125 nm.

  Here, the compounding amount of the carbon black is preferably in the range of 10 to 150 parts, particularly preferably in the range of 50 to 100 parts with respect to 100 parts of the halogenated butyl rubber. That is, if the amount of the carbon black is too small, it tends to be difficult to obtain high attenuation. Conversely, if the amount of the carbon black is too large, the kneadability tends to deteriorate. Because.

  Examples of the hydrazide compound include carbodihydrazide (CDH), isophthalic acid dihydrazide (IDH), adipic acid dihydrazide (ADH), sebacic acid dihydrazide (SDH), dodecanedioic acid dihydrazide (N-12), and succinic acid dihydrazide (SUDH). ) And the like, and derivatives thereof such as derivatives represented by the following general formulas (1) to (3). These may be used alone or in combination of two or more. Among these, adipic acid dihydrazide is preferable from the viewpoint of lowering the dynamic magnification.

  In the general formula (1), examples of the divalent group derived from the aromatic ring represented by A include, for example, a phenylene group, a naphthylene group, or any of ortho-position, para-position, and meta-position as a connecting position, Examples include a pyridylene group and a quinolylene group. Moreover, as a bivalent group derived from a C1-C18 saturated or unsaturated linear hydrocarbon represented by said A, both ends of a C1-C18 saturated or unsaturated linear hydrocarbon And a hydrocarbon group in which the carbon atom is a connecting position, for example, an ethylene group, a tetramethylene group, a heptamethylene group, an octamethylene group, an octadecamethylene group, a 7,11-octadecadienylene group, and the like.

  In the general formula (2), B is a monovalent aromatic group such as a phenyl group or a naphthyl group, and the substitution position of the hydroxyl group or amino group which is X as the substituent of B is ortho-position, Either the meta position or the para position may be used, but the ortho position is particularly preferable.

  In the above general formula (3), Y is a pyridyl group or a hydrazino group, and the bonding position is preferably the 2nd or 3rd position in the pyridyl group.

In the general formulas (1) to (3), R ^{1 to} R ⁴ are each independently hydrogen, an alkyl group having 1 to 18 carbon atoms, a cycloalkyl group, or a monovalent aromatic ring group, preferably Hydrogen, an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, a phenyl group, and the like.

  Specific examples of the compound represented by the general formula (1) include isophthalic acid dihydrazide and adipic acid dihydrazide derivatives such as di (1-methylethylidene) hydrazide, adipic acid di (1-methylethylidene) hydrazide, and isophthalic acid. Acid di (1-methylpropylidene) hydrazide, adipic acid di (1-methylpropylidene) hydrazide, isophthalic acid di (1,3-dimethylpropylidene) hydrazide, adipic acid di (1,3-dimethylpropylidene) hydrazide , Di (1-phenylethylidene) hydrazide, isophthalic acid, di (1-phenylethylidene) hydrazide, and the like. The derivatives of the following dihydrazide compounds other than these isophthalic acid dihydrazide and adipic acid dihydrazide are the same. Effective It is. For example, terephthalic acid dihydrazide, azelaic acid dihydrazide, succinic acid dihydrazide, icosanoic dicarboxylic acid dihydrazide and the like. Among these, isophthalic acid dihydrazide is preferable in that it has an excellent effect of reducing the dynamic speed.

  Specific compounds represented by the general formula (2) include 2-naphthalenic acid-3-hydroxy (1-methylethylidene) hydrazide, 2-naphthalenic acid-3-hydroxy (1-methylpropylidene) hydrazide, 2 -Derivatives of 2-naphthalenic acid-3-hydroxyhydrazide such as naphthalenic acid-3-hydroxy (1,3-dimethylpropylidene) hydrazide, 2-naphthalenic acid-3-hydroxy (1-phenylethylidene) hydrazide, Examples include salicylic acid hydrazide, 4-hydroxybenzoic acid hydrazide, anthranilic acid hydrazide, and 1-hydroxy-2-naphthalene acid hydrazide. Of these, derivatives of 2-naphthalenic acid-3-hydroxyhydrazide, in particular, 2-naphthalenic acid-3-hydroxy (1-methylethylidene) hydrazide are preferable because they are excellent in a low doubling effect.

  Specific compounds represented by the general formula (3) include isonicotinic acid (1-methylethylidene) hydrazide, isonicotinic acid (1-methylpropylidene) hydrazide, isonicotinic acid (1,3-dimethylpropylidene). In addition to derivatives of isonicotinic acid hydrazide such as hydrazide and isonicotinic acid (1-phenylethylidene) hydrazide, derivatives of carbonic acid dihydrazide are exemplified.

  In addition, the synthesis | combining method of the hydrazide compound represented by the said General formula (1)-(3) is Pant, UC; Ramchandran, Reena; Joshi, BCRev.Roum.Chim. (1979) 24 (3), 471-82. In the literature.

  The derivatives represented by the general formulas (1) to (3) are used alone or in combination of two or more.

  The blending amount of the hydrazide compound is preferably in the range of 0.01 to 5 parts, particularly preferably in the range of 0.1 to 3 parts, with respect to 100 parts of the halogenated butyl rubber. That is, if the blending amount of the hydrazide compound is too small, the effect of lowering the dynamic ratio tends to be reduced. Conversely, if the blending amount of the hydrazide compound is too large, the physical properties tend to decrease. is there.

  Examples of the process oil include naphthenic oil, paraffinic oil, and aroma oil. These may be used alone or in combination of two or more. The blending amount of the process oil is preferably in the range of 1 to 50 parts, particularly preferably in the range of 3 to 30 parts with respect to 100 parts of the halogenated butyl rubber.

  In the present invention, the anti-vibration rubber composition is prepared by kneading the master batch and the diene rubber. In the kneading step with the diene rubber, in addition to the diene rubber, silica filler, silane coupling agent, carbon black, cross-linking agent, cross-linking accelerator, cross-linking auxiliary, anti-aging agent, process oil, etc. If necessary, it may be blended appropriately.

  Examples of the diene rubber include natural rubber (NR), isoprene rubber (IR), butadiene rubber (BR), styrene butadiene rubber (SBR), acrylonitrile butadiene rubber (NBR), and the like. These may be used alone or in combination of two or more.

  The silica-based filler refers to a filler having silica as an active ingredient, and examples thereof include silica, clay, sericite, calcium silicate, and aluminum silicate. These may be used alone or in combination of two or more. Among these, silica is preferable from the viewpoint of reinforcing properties.

  The blending amount of the silica-based filler is preferably in the range of 5 to 100 parts, particularly preferably in the range of 10 to 60 parts with respect to 100 parts of the diene rubber from the viewpoint of physical properties.

  In the present invention, a silane coupling agent may be added for the purpose of improving the affinity between the silica filler and the diene rubber. A specific example of the silane coupling agent is Si69 manufactured by EVONIK DEGUSSA. In the case of using silica treated with a silane coupling agent whose surface is treated with a silane coupling agent as the silica-based filler, it is not necessary to add a silane coupling agent.

  The blending amount of the silane coupling agent is preferably in the range of 0.2 to 20 parts, particularly preferably in the range of 1 to 10 parts, relative to 100 parts of the halogenated butyl rubber, from the viewpoint of affinity with the diene rubber. It is.

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

  In addition, the said carbon black may mix | blend two or more types of carbon black from which a particle size differs.

  The average particle size of the carbon black having a small particle size is preferably in the range of 14 to 40 nm, particularly preferably in the range of 20 to 35 nm. The average particle size of the large particle size carbon black is preferably in the range of 41 to 125 nm, particularly preferably in the range of 60 to 125 nm.

  Here, the compounding amount of the carbon black is preferably in the range of 10 to 150 parts, particularly preferably in the range of 50 to 100 parts with respect to 100 parts of the diene rubber. That is, if the amount of the carbon black is too small, it tends to be difficult to obtain high attenuation. Conversely, if the amount of the carbon black is too large, the kneadability tends to deteriorate. Because.

  Examples of the crosslinking agent include resin-based crosslinking agents (alkylphenol disulfide and the like), sulfur and the like. These may be used alone or in combination of two or more.

  The amount of the cross-linking agent is preferably in the range of 0.5 to 7 parts, particularly preferably in the range of 0.5 to 5 parts, with respect to 100 parts of the diene rubber.

  Examples of the crosslinking accelerator include thiazole-based, sulfenamide-based, thiuram-based, aldehyde ammonia-based, aldehyde amine-based, guanidine-based, and thiourea-based crosslinking accelerators. These may be used alone or in combination of two or more. Among these, a sulfenamide-based crosslinking accelerator is preferable from the viewpoint of excellent crosslinking reactivity.

  The blending amount of the crosslinking accelerator is preferably in the range of 0.1 to 10 parts, particularly preferably in the range of 1 to 5 parts with respect to 100 parts of the diene rubber.

  Examples of the thiazole-based crosslinking accelerator include dibenzothiazyl disulfide (MBTS), 2-mercaptobenzothiazole (MBT), 2-mercaptobenzothiazole sodium salt (NaMBT), and 2-mercaptobenzothiazole zinc salt (ZnMBT). Can be given. These may be used alone or in combination of two or more. Among these, dibenzothiazyl disulfide (MBTS) and 2-mercaptobenzothiazole (MBT) are preferable in terms of excellent crosslinking reactivity.

  Examples of the sulfenamide-based crosslinking accelerator include N-oxydiethylene-2-benzothiazolylsulfenamide (NOBS), N-cyclohexyl-2-benzothiazolylsulfenamide (CBS), Nt- Examples thereof include butyl-2-benzothiazoylsulfenamide (BBS) and N, N′-dicyclohexyl-2-benzothiazoylsulfenamide. These may be used alone or in combination of two or more.

  Examples of the thiuram crosslinking accelerator include tetramethylthiuram disulfide (TMTD), tetraethylthiuram disulfide (TETD), tetrabutylthiuram disulfide (TBTD), tetrakis (2-ethylhexyl) thiuram disulfide (TOT), tetrabenzylthiuram disulfide. (TBzTD) and the like. These may be used alone or in combination of two or more.

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

  The amount of the crosslinking aid is preferably in the range of 1 to 25 parts, particularly preferably in the range of 3 to 10 parts, with respect to 100 parts of the diene rubber.

  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 may be used alone or in combination of two or more.

  The blending amount of the anti-aging agent is preferably in the range of 1 to 10 parts, particularly preferably in the range of 2 to 5 parts, with respect to 100 parts of the diene rubber.

  Examples of the process oil include naphthenic oil, paraffinic oil, and aroma oil. These may be used alone or in combination of two or more.

  The blending amount of the process oil is preferably in the range of 1 to 50 parts, particularly preferably in the range of 3 to 30 parts with respect to 100 parts of the diene rubber.

  The production method of the vibration-proof rubber composition of the present invention is performed, for example, as follows. First, a halogenated butyl rubber, a silica-based filler, a silane coupling agent and, if necessary, a hydrazide compound are appropriately blended, and these are mixed for a predetermined time (usually 2 to 6 minutes) using a Banbury mixer or the like. About) Kneading to prepare a master batch. Next, this master batch, a diene rubber, and a silica filler, a silane coupling agent, carbon black and the like are appropriately blended as necessary, and these are used in a predetermined condition (usually 100) using a roll or the like. Anti-vibration rubber composition is prepared by kneading at ~ 130 ° C x 2 to 6 minutes. And the anti-vibration rubber | gum can be obtained by bridge | crosslinking the obtained anti-vibration rubber composition at high temperature (normally 150-170 degreeC) for the predetermined time (normally 5-30 minutes).

  In the vibration-proof rubber obtained by the production method of the present invention, usually only the silica-based filler is dispersed in the region of the halogenated butyl rubber (island phase). However, in some cases, a small amount of silica-based filler may be dispersed in the sea phase region. The sea-island structure can be observed in a 10 μm × 10 μm visual field using, for example, a scanning probe microscope (SPM).

  In the present invention, the masterbatch is preferably prepared at a high temperature as described above. In the present invention, the high temperature usually refers to a range of 130 to 170 ° C, preferably 140 to 160 ° C.

  The mixing ratio of the halogenated butyl rubber and the diene rubber is preferably in the range of halogenated butyl rubber / diene rubber = 20/80 to 90/10, particularly preferably halogenated butyl rubber / diene rubber = It is in the range of 30/70 to 50/50. That is, when the weight mixing ratio of the halogenated butyl rubber is less than the lower limit (the weight mixing ratio of the diene rubber exceeds the upper limit), it tends to be difficult to obtain sufficient dynamic characteristics. When the weight mixing ratio of the butyl rubber exceeds the upper limit (the weight mixing ratio of the diene rubber is less than the lower limit), the dynamic characteristics are improved, but the physical properties tend to be lowered.

  The anti-vibration rubber composition obtained by the production method of the present invention includes, for example, engine mounts, body mounts, cab mounts, member mounts, strut mounts, stabilizer bushes, strut bar cushions, bushes (suspension bushes, etc.) used for automobile vehicles and the like. It is preferably used as a vibration isolating material such as a bush (suspension bush etc.).

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

  First, prior to the examples and comparative examples, the following materials were prepared.

[Natural rubber]
RSS # 3

[Chlorinated butyl rubber]
Chlorobutyl 1066, manufactured by JSR Corporation

[Carbon black 1]
FEF grade carbon black (manufactured by Tokai Carbon Co., Ltd., Seest SO, average particle size: 43 nm)

[Carbon black 2]
HAF grade carbon black (manufactured by Tokai Carbon Co., Ltd., Seest 3, average particle size: 28 nm)

[Zinc oxide]
2 types of zinc oxide manufactured by Sakai Chemical Industry Co., Ltd.

〔stearic acid〕
Lunac S30, made by Kao

[Anti-aging agent]
Nocrack 6C manufactured by Ouchi Shinsei Chemical Co., Ltd.

〔wax〕
Sunnock, manufactured by Ouchi Shinsei Chemical Co., Ltd.

〔silica〕
NIPSEAL ER made by Tosoh Silica

[Silica treated with silane coupling agent]
EVONIK DEGUSSA, Capsule 8113

[Clay A]
J. et al. M.M. Made by Huber, Polyfil 80

[Clay B]
Takehara Chemical Industry Co., Ltd., No. 5 clay

[Hydrazide]
Made by Nippon Finechem, ADH

〔Silane coupling agent〕
EV69, manufactured by EVONIK DEGUSSA, Si69

[Aroma oil]
Made by Fuji Kosan Co., Ltd., Futsukor Aromax # 1

[Crosslinking accelerator]
Ouchi Shinsei Chemical Co., Ltd., Noxeller CZ-G

[Crosslinking agent (resin-based crosslinking agent)]
Alkyl phenol disulfide (Taoka Chemical Co., Ltd., Tactrol AP)

  First, a master batch was prepared using each of the above materials as follows.

[Preparation of masterbatches 1-7]
As shown in Table 1 below, the components shown in the same table were blended in the proportions shown in the same table, and these were kneaded at a predetermined temperature shown in Table 1 for 3 minutes using a Banbury mixer to prepare a master batch. .

  Next, an anti-vibration rubber composition was prepared as follows using each of the master batches.

[Examples 1-8]
As shown in Table 2 and Table 3 below, each component was blended in the proportions shown in the same table, and kneaded with a roll to prepare a vibration-proof rubber composition.

[Comparative Examples 1-6]
An anti-vibration rubber composition was prepared in substantially the same manner as in Example 1 except that the respective components were blended without depending on the masterbatch method. That is, as shown in Table 3 below, the components were blended in the proportions shown in the same table and kneaded with a roll to prepare a vibration-proof rubber composition.

  About each anti-vibration rubber composition obtained in this way, each characteristic was evaluated according to the following reference | standard. The results are shown in Tables 2 and 3 above.

[Initial physical properties]
Each anti-vibration rubber composition was press-molded and crosslinked under conditions of 160 ° C. × 20 minutes to produce a rubber sheet having a thickness of 2 mm. A JIS No. 5 dumbbell was punched from this rubber sheet, and using this dumbbell, tensile strength (TS), elongation at break (Eb) and hardness (Hs: JIS A) were measured according to JIS K6251.

(Dynamic characteristics)
(Static spring constant: Ks)
Each anti-vibration rubber composition was used, and a disk-shaped metal fitting (diameter 60 mm, thickness 6 mm) was pressed and crosslinked and bonded to the upper and lower surfaces of a rubber piece (diameter 50 mm, height 25 mm) under a crosslinking condition of 170 ° C. × 30 minutes. A test piece was prepared. Next, the test piece was compressed by 7 mm in the cylinder axis direction, and the static spring constant (Ks) was calculated by reading the load at the time of deflection of 1.5 mm and 3.5 mm from the load deflection curve of the second round. .

(Dynamic spring constant: Kd100)
The test piece is compressed 2.5 mm in the cylinder axis direction, a constant displacement harmonic compression vibration with an amplitude of 0.05 mm centered on the position of the 2.5 mm compression is applied at a frequency of 100 Hz, and a dynamic load is applied to the upper load cell. The dynamic spring constant (Kd100) was calculated and measured according to JIS K 6394.

(Tan δ)
With the test piece compressed in the axial direction by 2.5 mm, a test is performed to apply a constant displacement harmonic compression vibration with an amplitude of ± 0.5 mm centered on the compression position at a frequency of 15 Hz from below the test piece. , Tan δ (loss factor) at 15 Hz was determined in accordance with “Non-resonant method (a)” in “Test method for vibration-proof rubber” of JIS K 6385-1995.

(Dynamic magnification: Kd100 / Ks)
The dynamic magnification was determined as a value of dynamic spring constant (Kd100) / static spring constant (Ks).

  From the results shown in Tables 2 and 3 above, when Examples and Comparative Examples in which the blending amount of the silica-based filler is substantially the same are compared, Examples according to the masterbatch method have higher damping and lower dynamic spring characteristics. Excellent (low dynamic magnification).

  The anti-vibration rubber composition obtained by the production method of the present invention includes, for example, engine mounts, body mounts, cab mounts, member mounts, strut mounts, stabilizer bushes, strut bar cushions, bushes (suspension bushes, etc.) used for automobile vehicles and the like. It is preferably used as a vibration isolating material such as a bush (suspension bush etc.).

Claims (6)

  A master batch is prepared by kneading a halogenated butyl rubber, a silica-based filler, and a silane coupling agent, and then the master batch and a diene-based rubber are kneaded so that the silica-based filler is used as the halogenated butyl rubber. A method for producing an anti-vibration rubber composition, characterized by being dispersed therein.   The method for producing an anti-vibration rubber composition according to claim 1, wherein a carbon black added to the diene rubber is kneaded with the master batch.   The method for producing a vibration-insulating rubber composition according to claim 1 or 2, wherein a master batch is prepared by adding carbon black.   The method for producing a vibration-proof rubber composition according to any one of claims 1 to 3, wherein the silica-based filler is at least one of silica and clay.   The method for producing a vibration-insulating rubber composition according to any one of claims 1 to 4, wherein a master batch is prepared by kneading at a high temperature of 130 to 170 ° C.   Anti-vibration rubber composition obtained by the manufacturing method as described in any one of Claims 1-5.