JP2016190986A - Composition for vibration-proof rubber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a composition for vibration-proof rubber capable of providing a rubber crosslinked article low in dynamic magnification and excellent in durability.SOLUTION: There is provided a composition for vibration-proof rubber containing a terminal modified group-containing cyclic olefin ring-opened polymer and silica having nitrogen adsorption specific surface area measured by a BTE method of 100 m/g with percentage content of the silica of 30 to 200 pts.wt. based on 100 pts.wt. of a rubber component contained in the composition for vibration-proof rubber.SELECTED DRAWING: None

Description

  The present invention relates to an anti-vibration rubber composition that can provide a rubber cross-linked product having a low dynamic ratio and excellent durability, and can be suitably used for an anti-vibration rubber member.

  Anti-vibration rubber members are used for the purpose of reducing vibration and noise generated from driving parts such as automobiles, vehicle engines, power transmission units, and motor rotations. The anti-vibration characteristics required for the anti-vibration rubber member include anti-vibration properties that suppress the influence of engine vibration on the vehicle body, and anti-vibration properties that suppress the noise caused by high engine rotation. Conventionally, natural rubber, or natural rubber and other conjugated diene rubbers have been used for these vibration-proof rubber members as raw rubber. However, in recent years, with higher output and higher grades of automobiles, the demand for improved ride comfort and quietness in the passenger compartment has increased, and anti-vibration rubbers with excellent vibration isolation characteristics, especially dynamic magnification, which is an index of sound insulation. There is a need for components.

In order to meet these requirements, for example, in Patent Document 1, the diene rubber has a silanol group density of 3.0 or more / nm ² on the silica surface, an average particle diameter of 10 μm or less, and a BET specific surface area of 15 An anti-vibration rubber composition containing silica of ˜60 m ² / g and a silane coupling agent has been proposed.

  However, the rubber cross-linked product obtained using the anti-vibration rubber composition of Patent Document 1 still has sufficient characteristics required for the anti-vibration rubber member, specifically, low dynamic magnification and durability. However, further improvement in dynamic magnification and durability has been desired.

JP 2011-195807 A

  The object of the present invention has been made in view of such a situation, and a composition for vibration-proof rubber capable of providing a crosslinked rubber having a low dynamic magnification and excellent durability, and the vibration-proof rubber. It is providing the rubber crosslinked material obtained using a composition.

As a result of intensive studies to achieve the above object, the present inventors have added silica having a nitrogen adsorption specific surface area of 100 m ² / g or less measured by a BET method to a terminally modified group-containing cyclic olefin ring-opening polymer. It has been found that the above object can be achieved by a rubber composition containing a specific amount, and the present invention has been completed.

That is, according to the present invention, an anti-vibration rubber composition containing a terminal-modified group-containing cyclic olefin ring-opening polymer and silica having a nitrogen adsorption specific surface area of 100 m ² / g or less as measured by the BET method. And the composition for vibration-proof rubbers whose content rate of the said silica is 30-200 weight part with respect to 100 weight part of rubber components contained in the said composition for vibration-proof rubber is provided.

In the vibration-proof rubber composition of the present invention, the terminal-modified group-containing cyclic olefin ring-opening polymer is preferably a polymer having an oxysilyl group introduced at the end of the polymer chain.
The anti-vibration rubber composition of the present invention preferably further contains natural rubber as a rubber component.
In the vibration-proof rubber composition of the present invention, the content of the natural rubber in the rubber component is preferably 30 to 90% by weight.

  The present invention also provides a rubber cross-linked product obtained by cross-linking the vibration-proof rubber composition described above, and a vibration-proof rubber member containing the rubber cross-linked product.

  According to the present invention, it is obtained using a vibration-proof rubber composition capable of giving a rubber cross-linked product having a low dynamic magnification and excellent durability, and the vibration-proof rubber composition. A rubber cross-linked product having excellent durability is provided.

<Composition for anti-vibration rubber>
The anti-vibration rubber composition of the present invention is for an anti-vibration rubber containing a terminal-modified group-containing cyclic olefin ring-opening polymer and silica having a nitrogen adsorption specific surface area of 100 m ² / g or less as measured by the BET method. It is a composition, Comprising: It is a composition whose content rate of the said silica is the range of 30-200 weight part with respect to 100 weight part of rubber components contained in the said composition for vibration-proof rubber.

<Terminal modified group-containing cyclic olefin ring-opening polymer>
The terminal modified group-containing cyclic olefin ring-opening polymer used in the present invention contains a repeating unit formed by ring-opening polymerization of a cyclic olefin as a repeating unit constituting the main chain, It contains a modifying group.

  The cyclic olefin for forming the terminally modified group-containing cyclic olefin ring-opening polymer used in the present invention is not particularly limited, and examples thereof include monocyclic olefins, monocyclic dienes, monocyclic trienes and polycyclic cyclic olefins, Examples include polycyclic cyclic dienes and polycyclic cyclic trienes. Examples of the monocyclic olefin include cyclopentene which may have a substituent and cyclooctene which may have a substituent. Examples of the monocyclic diene include 1,5-cyclooctadiene which may have a substituent. Examples of the monocyclic triene include 1,5,9-cyclododecatriene which may have a substituent. Examples of the polycyclic olefin include norbornene compounds which may have a substituent. Of these, cyclopentene is preferred. The terminal modified group-containing cyclic olefin ring-opening polymer used in the present invention is derived from a polymer consisting only of a structural unit derived from cyclopentene or a monomer copolymerizable with cyclopentene as a repeating unit constituting the main chain. It is preferable that the copolymer consists of the following structural units. The proportion of the structural unit derived from cyclopentene in the terminal modified group-containing cyclic olefin ring-opening polymer used in the present invention is preferably 80 mol% or more, and 90 mol% or more, based on all repeating units. Is more preferably 95 mol% or more, and the terminally modified group-containing cyclic olefin ring-opening polymer used in the present invention is particularly preferably a polymer composed only of a structural unit derived from cyclopentene. When the proportion of the structural unit derived from cyclopentene is within the above range, the glass transition temperature of the terminally modified group-containing cyclic olefin ring-opening polymer used in the present invention can be set low, and as a result, the behavior of the resulting rubber cross-linked product can be reduced. The magnification can be low.

  The molecular weight of the terminally modified group-containing cyclic olefin ring-opening polymer used in the present invention is not particularly limited, but the polystyrene-converted weight average molecular weight (Mw) value measured by gel permeation chromatography is 100,000 to It is preferably 1,000,000, more preferably 150,000 to 900,000, and even more preferably 200,000 to 800,000. When the terminal modified group-containing cyclic olefin ring-opening polymer has such a molecular weight, it becomes possible to give a rubber cross-linked product having excellent mechanical properties.

  Ratio (Mw / Mn) of polystyrene-equivalent number average molecular weight (Mn) and weight average molecular weight (Mw) of the terminal modified group-containing cyclic olefin ring-opening polymer used in the present invention, measured by gel permeation chromatography. Although it is not specifically limited, Usually, it is 1.1-5.0, Preferably it is 1.2-4.5, More preferably, it is 1.3-4.0. In addition, it becomes possible to give the rubber crosslinked material which has the outstanding mechanical property by having such Mw / Mn.

  In the double bond present in the repeating unit constituting the terminally modified group-containing cyclic olefin ring-opening polymer used in the present invention, the cis / trans ratio is not particularly limited, but is usually in the range of 10/90 to 90/10. From the viewpoint of obtaining a vibration-proof rubber composition capable of giving a rubber cross-linked product excellent in vibration-proof characteristics, the ratio is preferably in the range of 15/85 to 85/15, and 20/80 to 80 More preferably, it is in the range of / 20.

  The glass transition temperature of the terminally modified group-containing cyclic olefin ring-opening polymer used in the present invention is preferably −120 to −90 ° C. from the viewpoint that the dynamic ratio can be further lowered when a rubber cross-linked product is used. More preferably, it is -120 to -95 degreeC, More preferably, it is -120 to -100 degreeC. The glass transition temperature of the terminally modified group-containing cyclic olefin ring-opening polymer can be adjusted, for example, by adjusting the cis / trans ratio in the double bond present in the repeating unit.

  The terminally modified group-containing cyclic olefin ring-opening polymer used in the present invention may have a melting point. When the terminal-modified group-containing cyclic olefin ring-opening polymer has a melting point, the temperature is preferably 0 ° C. or less, and −10 ° C. or less from the viewpoint of improving rubber properties at low temperatures. It is more preferable that The presence or absence of the melting point of the terminally modified group-containing cyclic olefin ring-opening polymer, and the temperature in the case of having the melting point, can be adjusted by adjusting the cis / trans ratio in the double bond present in the repeating unit. it can.

  The terminal modified group-containing cyclic olefin ring-opening polymer used in the present invention has a modified group at the end of the polymer chain, and such a modified group is not particularly limited, but is a group 15 atom of the periodic table. And a modifying group containing an atom selected from the group consisting of a group 16 atom of the periodic table and a silicon atom. By containing the terminal modification group, it is possible to increase the affinity for silica, thereby increasing the dispersibility of silica in the rubber composition, and as a result, in the case of a rubber cross-linked product, The dynamic magnification can be lowered, and the anti-vibration characteristics can be improved.

  As a modifying group for forming a terminal modifying group, it is possible to increase the affinity for silica, thereby, in the case of a rubber cross-linked product, from the viewpoint that the dynamic power can be lowered, nitrogen atom, A modified group containing an atom selected from the group consisting of an oxygen atom, a phosphorus atom, a sulfur atom, and a silicon atom is more preferable, and among these, an atom selected from the group consisting of a nitrogen atom, an oxygen atom, and a silicon atom is selected. The modifying group to be contained is more preferable.

  Examples of the modifying group containing a nitrogen atom include an amino group, a pyridyl group, an imino group, an amide group, a nitro group, a urethane linking group, or a hydrocarbon group containing these groups. Examples of the modifying group containing an oxygen atom include a hydroxyl group, a carboxylic acid group, an ether group, an ester group, a carbonyl group, an aldehyde group, an epoxy group, or a hydrocarbon group containing these groups. Examples of the modifying group containing a silicon atom include an alkylsilyl group, an oxysilyl group, and a hydrocarbon group containing these groups. Examples of the modifying group containing a phosphorus atom include a phosphoric acid group, a phosphino group, and a hydrocarbon group containing these groups. Examples of the modifying group containing a sulfur atom include a sulfonyl group, a thiol group, a thioether group, or a hydrocarbon group containing these groups. The modifying group may be a modifying group containing a plurality of the groups described above. Among these, specific examples of the modifying group that are particularly suitable from the viewpoint that the dynamic magnification in the case of a rubber cross-linked product can be further reduced, and thereby the vibration-proof property can be further improved, include amino Groups, pyridyl groups, imino groups, amide groups, hydroxyl groups, carboxylic acid groups, aldehyde groups, epoxy groups, oxysilyl groups, or hydrocarbon groups containing these groups. From the viewpoint of affinity for silica, oxysilyl groups are Particularly preferred. The oxysilyl group refers to a group having a silicon-oxygen bond.

  Specific examples of the oxysilyl group include an alkoxysilyl group, an aryloxysilyl group, an acyloxy group, an alkylsiloxysilyl group, and an arylsiloxysilyl group. Moreover, the hydroxy silyl group formed by hydrolyzing an alkoxy silyl group or an aryloxy silyl group and an acyloxy group can be mentioned. Among these, an alkoxysilyl group is preferable from the viewpoint of affinity for silica.

  The alkoxysilyl group is a group in which one or more alkoxy groups are bonded to a silicon atom. Specific examples thereof include a trimethoxysilyl group, a (dimethoxy) (methyl) silyl group, and a (methoxy) (dimethyl) silyl group. Group, (methoxy) (dichloro) silyl group, triethoxysilyl group, (diethoxy) (methyl) silyl group, (ethoxy) (dimethyl) silyl group, (dimethoxy) (ethoxy) silyl group, (methoxy) (diethoxy) silyl Group, tripropoxysilyl group and the like.

  An aryloxysilyl group is a group in which one or more aryloxy groups are bonded to a silicon atom, and specific examples thereof include a triphenoxysilyl group, (diphenoxy) (methyl) silyl group, and (phenoxy) (dimethyl). Examples thereof include a silyl group, a (phenoxy) (dichloro) silyl group, a (diphenoxy) (ethoxy) silyl group, and a (phenoxy) (diethoxy) silyl group. Of these, the (diphenoxy) (ethoxy) silyl group and the (phenoxy) (diethoxy) silyl group also have an alkoxy group in addition to the aryloxy group, and therefore are classified as an alkoxysilyl group.

  An acyloxysilyl group is a group in which one or more acyloxy groups are bonded to a silicon atom. Specific examples thereof include triacyloxysilyl groups, (diasiloxy) (methyl) silyl groups, and (acyloxy) (dimethyl). A silyl group, (acyloxy) (dichloro) silyl group, etc. are mentioned.

  The alkylsiloxysilyl group is a group in which one or more alkylsiloxy groups are bonded to a silicon atom. Specific examples thereof include tris (trimethylsiloxy) silyl group, trimethylsiloxy (dimethyl) silyl group, triethylsiloxy ( And diethyl) silyl group and tris (dimethylsiloxy) silyl group.

  The arylsiloxysilyl group is a group in which one or more arylsiloxy groups are bonded to a silicon atom. Specific examples thereof include tris (triphenylsiloxy) silyl group, triphenylsiloxy (dimethyl) silyl group, tris And (diphenylsiloxy) silyl group.

  The hydroxysilyl group is a group in which one or more hydroxy groups are bonded to a silicon atom. Specific examples thereof include a trihydroxysilyl group, a (dihydroxy) (methyl) silyl group, and a (hydroxy) (dimethyl) silyl group. , (Hydroxy) (dichloro) silyl group, (dihydroxy) (ethoxy) silyl group, (hydroxy) (diethoxy) silyl group, and the like. Of these, the (dihydroxy) (ethoxy) silyl group and the (hydroxy) (diethoxy) silyl group also have an alkoxy group in addition to the hydroxy group, and therefore are classified as an alkoxysilyl group.

  The terminal modified group-containing cyclic olefin ring-opening polymer used in the present invention has both polymer chain ends (both ends) even if a modified group is introduced only at one polymer chain end (one end). The modified group may be introduced in the mixture, or these may be mixed.

The introduction ratio of the modifying group at the terminal of the polymer chain of the terminal modified group-containing cyclic olefin ring-opening polymer used in the present invention is not particularly limited, but the number of cyclic olefin ring-opened polymer chain terminals having a modified group introduced / cyclic The percentage value of the number of olefin polymer chains is preferably 70% or more, more preferably 80% or more, and still more preferably 90% or more. The higher the introduction ratio of the modifying group, the higher the affinity with silica, and thus the dynamic ratio of the resulting rubber cross-linked product can be lowered. The method for measuring the introduction ratio of the modifying group to the end of the polymer chain is not particularly limited. For example, the peak area ratio corresponding to the modifying group determined by ¹ H-NMR spectrum measurement and gel permeation chromatography It can be determined from the number average molecular weight determined from

  The method for synthesizing the terminally modified group-containing cyclic olefin ring-opening polymer used in the present invention is not particularly limited as long as the target polymer is obtained, but may be synthesized according to a conventional method. It can be synthesized by the method.

That is, the terminally modified group-containing cyclic olefin ring-opening polymer used in the present invention includes, for example, a periodic table group 6 transition metal compound (A) and an organoaluminum compound (B) represented by the following general formula (1). It can be obtained by ring-opening polymerization of a cyclic olefin in the presence of a polymerization catalyst and a modifying group-containing olefinically unsaturated hydrocarbon (C).
(R ¹ ) _3-x Al (OR ² ) _x (1)
(In the general formula (1), R ¹ and R ² represent a hydrocarbon group having 1 to 20 carbon atoms, and x is 0 <x <3.)

  The periodic table group 6 transition metal compound (A) is a compound having a periodic table (long period type periodic table, hereinafter the same) group 6 transition metal atom, specifically, a chromium atom, a molybdenum atom, or a tungsten atom. A compound having a molybdenum atom or a compound having a tungsten atom is preferable, and a compound having a tungsten atom is more preferable from the viewpoint of high solubility in a cyclic olefin. The group 6 transition metal compound (A) in the periodic table is not particularly limited as long as it is a compound having a group 6 transition metal atom in the periodic table. , Arylates, oxydides, and the like. Among these, halides are preferable from the viewpoint of high polymerization activity.

  Specific examples of such a periodic table Group 6 transition metal compound (A) include molybdenum compounds such as molybdenum pentachloride, molybdenum oxotetrachloride, and molybdenum (phenylimide) tetrachloride; tungsten hexachloride, tungsten oxotetrachloride, Tungsten compounds such as tungsten (phenylimido) tetrachloride, monocatecholate tungsten tetrachloride, bis (3,5-ditertiarybutyl) catecholate tungsten dichloride, bis (2-chloroetherate) tetrachloride, tungsten oxotetraphenolate And so on.

  The use amount of the Group 6 transition metal compound (A) in the periodic table is usually 1: 100 to 1: 200,000, preferably 1 in terms of the molar ratio of “Group 6 transition metal atom in the polymerization catalyst: cyclic olefin”. : 200 to 1: 150,000, more preferably 1: 500 to 1: 100,000. When there is too little usage-amount of a periodic table group 6 transition metal compound (A), a polymerization reaction may not fully advance. On the other hand, if the amount is too large, removal of the catalyst residue from the terminally modified group-containing cyclic olefin ring-opening polymer becomes difficult, and the dynamic ratio of the resulting rubber cross-linked product may increase.

The organoaluminum compound (B) is a compound represented by the general formula (1). Specific examples of the hydrocarbon group having 1 to 20 carbon atoms represented by R ¹ and R ² in the general formula (1) include a methyl group, an ethyl group, an isopropyl group, an n-propyl group, an isobutyl group, and an n-butyl group. Group, alkyl group such as t-butyl group, n-hexyl group and cyclohexyl group; aryl group such as phenyl group, 4-methylphenyl group, 2,6-dimethylphenyl group, 2,6-diisopropylphenyl group and naphthyl group And so on. In the compound represented by the general formula (1), the groups represented by R ¹ and R ² may be the same or different, but in the present invention, the resulting terminal modified group is contained. from the viewpoint of being able to increase the cis ratio of the cyclic olefin ring-opening polymer, of R ¹ and R ^2, at least R ² is preferably an alkyl group formed by bonding continuously carbon atoms 4 or more, In particular, n-butyl group, 2-methyl-pentyl group, n-hexyl group, cyclohexyl group, n-octyl group, or n-decyl group is more preferable.

In the general formula (1), x is 0 <x <3. That is, in the general formula (1), the composition ratio of R ¹ and OR ² can take any value in the ranges of 0 <3-x <3 and 0 <x <3, respectively. X is preferably 0.5 <x <1.5 from the viewpoint that the polymerization activity can be increased and the cis ratio of the resulting terminally modified group-containing cyclic olefin ring-opening polymer can be increased.

The organoaluminum compound (B) represented by the general formula (1) can be synthesized, for example, by a reaction between a trialkylaluminum and an alcohol as shown in the following general formula (2).
_{^{(R 1) 3 Al + xR}} 2 OH → (R 1) 3-x Al (OR 2) x + (R 1) x H (2)

  Note that x in the general formula (1) can be arbitrarily controlled by defining the reaction ratio of the corresponding trialkylaluminum and alcohol as shown in the general formula (2).

  Although the usage-amount of an organoaluminum compound (B) changes also with kinds of the organoaluminum compound (B) to be used, with respect to the periodic table group 6 transition metal atom which comprises a periodic table group 6 transition metal compound (A). The ratio is preferably 0.1 to 100 times mol, more preferably 0.2 to 50 times mol, and still more preferably 0.5 to 20 times mol. If the amount of the organoaluminum compound (B) used is too small, the polymerization activity may be insufficient, and if it is too large, side reactions tend to occur during ring-opening polymerization.

  The modifying group-containing olefinically unsaturated hydrocarbon (C) is a compound having a modifying group and one olefinic carbon-carbon double bond having metathesis reactivity. The presence of such a modifying group-containing olefinically unsaturated hydrocarbon (C) in the polymerization reaction system of the ring-opening polymerization reaction can introduce a modifying group at the polymer chain end of the cyclic olefin ring-opening polymer. it can. For example, when it is desired to introduce an oxysilyl group into the polymer chain end of the cyclic olefin ring-opening polymer, an oxysilyl group-containing olefinically unsaturated hydrocarbon may be present in the polymerization reaction system.

  As an example of such an oxysilyl group-containing olefinically unsaturated hydrocarbon, vinyl (trimethoxy) silane is introduced as a modified group introduced only at one end (one end) of a polymer chain of a cyclic olefin ring-opening polymer. , Vinyl (triethoxy) silane, allyl (trimethoxy) silane, allyl (methoxy) (dimethyl) silane, allyl (triethoxy) silane, allyl (ethoxy) (dimethyl) silane, styryl (trimethoxy) silane, styryl (triethoxy) silane, 2 -Alkoxysilane compounds such as styrylethyl (triethoxy) silane, allyl (triethoxysilylmethyl) ether, allyl (triethoxysilylmethyl) (ethyl) amine; vinyl (triphenoxy) silane, allyl (triphenoxy) silane, allyl ( Phenoxy Aryloxysilane compounds such as (dimethyl) silane; acyloxysilane compounds such as vinyl (triacetoxy) silane, allyl (triacetoxy) silane, allyl (diacetoxy) methylsilane, allyl (acetoxy) (dimethyl) silane; allyltris (trimethylsiloxy) ) Alkylsiloxysilane compounds such as silane; arylsiloxysilane compounds such as allyltris (triphenylsiloxy) silane; 1-allylheptamethyltrisiloxane, 1-allylnonamethyltetrasiloxane, 1-allylnonamethylcyclopentasiloxane, 1- Polysiloxane compounds such as allylundecamethylcyclohexasiloxane; and the like. Moreover, 1,4-bis (trimethoxysilyl) -2-butene, 1,4-bis (1,4) (2) is introduced as a modified group at both ends (both ends) of the polymer chain of the cyclic olefin ring-opening polymer. Alkoxysilane compounds such as triethoxysilyl) -2-butene and 1,4-bis (trimethoxysilylmethoxy) -2-butene; aryloxysilane compounds such as 1,4-bis (triphenoxysilyl) -2-butene An acyloxysilane compound such as 1,4-bis (triacetoxysilyl) -2-butene; an alkylsiloxysilane compound such as 1,4-bis [tris (trimethylsiloxy) silyl] -2-butene; Arylsiloxysilane compounds such as bis [tris (triphenylsiloxy) silyl] -2-butene; 1,4-bis (heptamethyltrisiloxy) 2-butene, 1,4-bis polysiloxane compounds such as (undecapeptide methylcyclohexanol siloxy) -2-butene; and the like.

  What is necessary is just to select suitably the usage-amount of modified group containing olefinic unsaturated hydrocarbon (C), such as an oxysilyl group containing olefinic unsaturated hydrocarbon, according to the molecular weight of the terminal modified group containing cyclic olefin ring-opening polymer to manufacture. However, the molar ratio of the cyclic olefin used in the polymerization is usually 1/100 to 1 / 100,000, preferably 1/200 to 1 / 50,000, more preferably 1/500 to 1 / 10,000. Range. The modified group-containing olefinically unsaturated hydrocarbon acts as a molecular weight modifier in addition to the effect of introducing the modified group into the polymer chain end of the cyclic olefin ring-opening polymer. If the amount of the modifying group-containing olefinically unsaturated hydrocarbon (C) is too small, the introduction rate of the modifying group in the terminal-modified group-containing cyclic olefin ring-opening polymer is low, and if it is too much, the terminal-modified group-containing cyclic is obtained. There exists a possibility that the molecular weight of an olefin ring-opening polymer may become low.

  In the case of using a polymerization catalyst containing the Group 6 transition metal compound (A) of the periodic table and the organoaluminum compound (B) represented by the general formula (1), the polymerization catalyst is from the viewpoint of improving the polymerization activity, In addition to these components, esters and / or ethers (D) may further be contained.

  Specific examples of esters and / or ethers (D) include ethers such as diethyl ether, tetrahydrofuran, ethylene glycol diethyl ether, 1,4-dioxane; ethyl acetate, butyl acetate, amyl acetate, octyl acetate, acetic acid 2 -Esters such as chloroethyl, methyl acetyl acrylate, ε-caprolactone, dimethyl glutarate, σ-heisanolactone, diacetoxyethane, and the like. Among these, 1,4-dioxane and ethyl acetate are preferable from the viewpoint that the addition effect can be further enhanced. These esters and / or ethers (D) can be used alone or in combination of two or more. Moreover, the usage-amount can be adjusted suitably.

  Using a polymerization catalyst containing a Group 6 transition metal compound (A) and an organoaluminum compound (B) in the periodic table and, if necessary, esters and / or ethers (D), these polymerization catalyst and modified group-containing olefin The ring-opening polymerization of the cyclic olefin can be carried out by bringing the cyclic unsaturated hydrocarbon (C) into contact with the cyclic olefin. The method for carrying out the ring-opening polymerization is not particularly limited. For example, in the presence of a cyclic olefin, an organoaluminum compound (B) and esters and / or ethers (D) used as necessary, A method of carrying out ring-opening polymerization of a cyclic olefin by adding a Group 6 transition metal compound (A) can be mentioned. Alternatively, the Group 6 transition metal compound (A) of the periodic table and the esters or ethers (D) used as necessary are mixed in advance, a cyclic olefin is added thereto, and then the organoaluminum compound (B) ) May be added to carry out ring-opening polymerization of the cyclic olefin. Furthermore, a periodic table group 6 transition metal compound (A) and an organoaluminum compound (B), and if necessary, esters and / or ethers (D) are mixed in advance, and a cyclic olefin is added thereto. By adding, ring-opening polymerization of a cyclic olefin may be performed. The modifying group-containing olefinically unsaturated hydrocarbon (C) may be preliminarily mixed with the cyclic olefin, or may be mixed with the cyclic olefin during ring-opening polymerization. After the ring-opening polymerization of a cyclic olefin, a modified group-containing olefinically unsaturated hydrocarbon (C) is added to the obtained ring-opening polymer to cause a metathesis reaction with the obtained ring-opening polymer. May be.

  The ring-opening polymerization reaction may be performed in the absence of a solvent or in a solution. As a solvent used when the ring-opening polymerization reaction is carried out in a solution, it is inactive in the polymerization reaction, the cyclic olefin used for the ring-opening polymerization, the above-described polymerization catalyst, and a modified group-containing olefinically unsaturated hydrocarbon (C). There is no particular limitation as long as it is a solvent that can dissolve the solvent, and examples thereof include hydrocarbon solvents and halogen solvents. Specific examples of the hydrocarbon solvent include aromatic hydrocarbons such as benzene, toluene, xylene, and ethylbenzene; aliphatic hydrocarbons such as n-hexane, n-heptane, and n-octane; cyclohexane, cyclopentane, methylcyclohexane, and the like And alicyclic hydrocarbons. Specific examples of the halogen-based solvent include alkyl halogens such as dichloromethane and chloroform; aromatic halogens such as chlorobenzene and dichlorobenzene.

  The polymerization reaction temperature is not particularly limited, but is preferably −100 ° C. or higher, more preferably −50 ° C. or higher, still more preferably 0 ° C. or higher, and particularly preferably 20 ° C. or higher. The upper limit of the polymerization reaction temperature is not particularly limited, but is preferably less than 100 ° C, more preferably less than 90 ° C, still more preferably less than 80 ° C, and particularly preferably less than 70 ° C. The polymerization reaction time is also not particularly limited, but is preferably 1 minute to 72 hours, more preferably 10 minutes to 20 hours.

  An anti-aging agent such as a phenol stabilizer, a phosphorus stabilizer, or a sulfur stabilizer may be added to the terminally modified group-containing cyclic olefin ring-opened polymer obtained by the polymerization reaction, if desired. What is necessary is just to determine suitably the addition amount of an anti-aging agent according to the kind etc. Furthermore, you may mix | blend extension oil if desired. When the terminal modified group-containing cyclic olefin ring-opened polymer is obtained as the polymer solution, a known recovery method may be employed to recover the polymer from the polymer solution. For example, a solvent such as steam stripping may be used. After separating the solid, the solid can be filtered off and dried to obtain a solid rubber.

  Further, when the terminal-modified group-containing cyclic olefin ring-opening polymer used in the present invention contains an oxysilyl group at the polymer chain end, the polymer chain and the oxysilyl group are added at the polymer chain end. It is good also as what has the structure (henceforth an "oxysilyl-urethane structure" suitably) couple | bonded with the group to contain through a urethane bond group.

  When the terminal-modified group-containing cyclic olefin ring-opening polymer used in the present invention has an oxysilyl-urethane structure, the terminal-modified group-containing cyclic olefin ring-opened polymer is obtained, for example, by the method described below. Can be synthesized.

  First, a cyclic olefin ring-opening polymer having a hydroxyl group at the polymer chain end is produced. The cyclic olefin ring-opening polymer having a hydroxyl group at the polymer chain end may be produced by a known method, and the method is not particularly limited. (I) In the presence of an olefin compound having a hydroxyl group, A method of ring-opening polymerization of a cyclic olefin using a ring-opening polymerization catalyst having resistance to hydroxyl groups, or (II) ring-opening not having resistance to hydroxyl groups in the presence of an olefin compound having a hydroxyl group protected by a protecting group A method of ring-opening polymerization of a cyclic olefin using a polymerization catalyst and deprotecting a hydroxyl group protected by a protecting group introduced at the terminal of the obtained polymer is preferable.

  In the method of ring-opening polymerization of a cyclic olefin using a ring-opening polymerization catalyst having resistance to a hydroxyl group in the presence of the olefin compound having a hydroxyl group, the olefin compound having a hydroxyl group that can be used is ethylenically unsaturated in the molecule. The compound is not particularly limited as long as it is a compound containing at least one bond and one hydroxyl group.

  Specific examples of the olefin compound having a hydroxyl group include allyl alcohol, 3-buten-1-ol, 4-penten-1-ol, 4-hexen-1-ol, 4-hepten-1-ol, and 5-decene-. 1-ol, 5-hexen-1-ol, 5-octen-1-ol, 6-hepten-1-ol, 4-hydroxystyrene, 2-allylphenol, allyl 4-hydroxybenzoate, 1-cyclohexyl-2 -Terminal olefin compounds containing a hydroxyl group such as buten-1-ol, ethylene glycol monoallyl ether, 3-allyloxy-1,2-propanediol, 2-butene-1,4-diol, 3-hexene-2, An internal olefin compound containing hydroxyl groups such as 5-diol on both sides of the carbon-carbon double bond can be mentioned. In addition, the olefin compound which has a hydroxyl group may be used individually by 1 type, and can also use 2 or more types together. When a terminal olefin compound containing a hydroxyl group is used as the olefin compound having a hydroxyl group, the hydroxyl group is introduced only at one polymer chain end (one end), and the hydroxyl groups are contained on both sides of the carbon-carbon double bond. When using an internal olefin compound, a hydroxyl group is introduced into both polymer chain ends (both ends).

  The olefin compound having a hydroxyl group can function as a chain transfer agent in a ring-opening polymerization reaction system using a ring-opening polymerization catalyst having resistance to a hydroxyl group, and can function as a molecular weight regulator. Therefore, the amount of the olefin compound having a hydroxyl group may be determined according to the molecular weight of the target terminal-modified group-containing cyclic olefin ring-opening polymer. Although the usage-amount of the olefin compound which has a hydroxyl group is not specifically limited, It selects normally in the range of 0.00001-0.01 mol with respect to 1 mol of cyclic olefins used for a polymerization reaction, Preferably it is 0.00005- It is selected in the range of 0.005 mol.

  Moreover, a ruthenium carbene complex can be mentioned as a ring-opening polymerization catalyst having resistance to a hydroxyl group that can be used in a method of ring-opening polymerization of a cyclic olefin in the presence of an olefin compound having a hydroxyl group.

  The ruthenium carbene complex is not particularly limited as long as it becomes a ring-opening polymerization catalyst for cyclic olefins. Specific examples of the ruthenium carbene complex preferably used include bis (tricyclohexylphosphine) benzylidene ruthenium dichloride, bis (triphenylphosphine) -3,3-diphenylpropenylidene ruthenium dichloride, bis (tricyclohexylphosphine) t-butylvinylidene. Ruthenium dichloride, bis (1,3-diisopropylimidazoline-2-ylidene) benzylidene ruthenium dichloride, bis (1,3-dicyclohexylimidazoline-2-ylidene) benzylidene ruthenium dichloride, (1,3-dimesitylmimidazoline-2-ylidene ) (Tricyclohexylphosphine) benzylideneruthenium dichloride, (1,3-dimesitylimidazolidine-2-ylidene) (tricyclohexylphosphite) ) Benzylidene ruthenium dichloride, bis (tricyclohexylphosphine) ethoxy methylidene ruthenium dichloride, and (1,3-dimesityl imidazolidine-2-ylidene) (tricyclohexylphosphine) ethoxy methylidene ruthenium dichloride.

  The amount of the ruthenium carbene complex used is not particularly limited, but the molar ratio of (metal ruthenium in the catalyst: cyclic olefin used for polymerization) is usually 1: 2,000 to 1: 2,000,000, The range is preferably 1: 5,000 to 1: 1,500,000, more preferably 1: 10,000 to 1: 1,000,000. If the amount used is too small, the polymerization reaction may not proceed sufficiently. On the other hand, if the amount is too large, it will be difficult to remove the catalyst residue from the resulting terminally modified group-containing cyclic olefin ring-opening polymer.

  The ring-opening polymerization reaction may be carried out in the absence of a solvent or in a solution. When polymerizing in a solution, the solvent used is inactive in the polymerization reaction and is not particularly limited as long as it is a solvent that can dissolve the cyclic olefin or polymerization catalyst used in the polymerization. For example, the above-described solvent may be used. it can.

  Although superposition | polymerization temperature is not specifically limited, Usually, it sets in the range of -50-100 degreeC. The polymerization reaction time is preferably 1 minute to 72 hours, more preferably 5 hours to 20 hours. After the polymerization conversion rate reaches a predetermined value, the polymerization reaction can be stopped by adding a known polymerization terminator to the polymerization system.

  As described above, a polymer solution containing a cyclic olefin ring-opening polymer having a hydroxyl group at the polymer chain end can be obtained. The cyclic olefin ring-opening polymer having a hydroxyl group at the polymer chain end is recovered from the polymer solution and then reacted with an isocyanate compound (in this application, a compound containing an oxysilyl group and an isocyanate group in the molecule). Alternatively, the polymer solution can be directly subjected to the reaction with the isocyanate compound. When the polymer is recovered from the polymer solution, a known recovery method may be employed. For example, after separating the solvent by steam stripping or the like, the solid is filtered off and further dried to obtain a solid rubber. The method of acquiring can be adopted.

  On the other hand, when ring-opening polymerization of a cyclic olefin using a ring-opening polymerization catalyst having no resistance to hydroxyl groups, the polymerization reaction is carried out in the presence of an olefin compound having a hydroxyl group protected by a protecting group. The object of protection may be the above-mentioned olefin compound having a hydroxyl group, and the hydroxyl group may be protected using a known protecting group as a hydroxyl protecting group. Specific examples of the hydroxyl-protecting group include an alkyl group, an acyl group, an RC (O)-group (where R is a saturated hydrocarbon group having 1 to 10 carbon atoms), a silyl group, and a metal alkoxide. Moreover, it is good also as an olefin compound which has the hydroxyl group protected by making the olefin compound which has a hydroxyl group react with a trialkylaluminum compound. In addition, when using the reaction material of the olefin compound and hydroxyl group compound which have a hydroxyl group, this reaction material can also fulfill | perform the function as an organometallic compound used as a promoter mentioned later.

  The olefin compound having a protected hydroxyl group functions as a chain transfer agent in the ring-opening polymerization reaction system, and can function as a molecular weight modifier. Therefore, the amount of the olefin compound having a protected hydroxyl group may be determined according to the molecular weight of the target terminal-modified group-containing cyclic olefin ring-opening polymer. The amount of the olefin compound having a protected hydroxyl group is not particularly limited, but is usually selected in the range of 0.00001 to 0.01 mol per mol of cyclic olefin used in the polymerization reaction, preferably 0. It is selected in the range of 0.0005 to 0.005 mol.

  The ring-opening polymerization catalyst used when the polymerization reaction is carried out in the presence of an olefin compound having a hydroxyl group protected by a protecting group is not limited as long as it can perform ring-opening polymerization of a cyclic olefin, but is preferably used. Examples of the polymerization catalyst include a molybdenum compound and a tungsten compound. As the molybdenum compound and the tungsten compound that can be used as the ring-opening polymerization catalyst, for example, those described above can be used.

  When using a molybdenum compound or a tungsten compound as a ring-opening polymerization catalyst, an organic metal compound may be used in combination as a promoter. Examples of the organometallic compound that can be used as the promoter include organometallic compounds of Group 1, 2, 12, 13 or 14 metal atoms of a periodic table having a hydrocarbon group having 1 to 20 carbon atoms. Among these, organolithium compounds, organomagnesium compounds, organozinc compounds, organoaluminum compounds, and organotin compounds are preferably used, organolithium compounds, organotin compounds, and organoaluminum compounds are more preferred, and organoaluminum is particularly preferred. It is done.

  Specific examples of the organic lithium compound that can be used as a cocatalyst include n-butyl lithium, methyl lithium, phenyl lithium, neopentyl lithium, and neophyll lithium. Specific examples of the organic magnesium compound include butylethylmagnesium, butyloctylmagnesium, dihexylmagnesium, ethylmagnesium chloride, n-butylmagnesium chloride, allylmagnesium bromide, neopentylmagnesium chloride, and neophyllmagnesium chloride. Specific examples of the organic zinc compound include dimethyl zinc, diethyl zinc, and diphenyl zinc. Specific examples of the organic tin compound include tetramethyltin, tetra (n-butyl) tin, and tetraphenyltin. Specific examples of the organoaluminum compound include trialkylaluminum such as trimethylaluminum, triethylaluminum and triisobutylaluminum, alkylaluminum halide such as diethylaluminum chloride, ethylaluminum sesquichloride and ethylaluminum dichloride, and the above general formula (1). The compound (organoaluminum compound (B)) represented by these is mentioned.

  The polymerization reaction conditions in the case of using a molybdenum compound or a tungsten compound as a ring-opening polymerization catalyst may be appropriately set within the range of the conditions described in the case of using a ruthenium carbene complex.

  The deprotection of the cyclic olefin ring-opened polymer having a hydroxyl group protected by a protecting group at the end of the polymer chain obtained as described above may be performed by a known method according to the protecting group used. Specific examples include methods such as deprotection by heating, deprotection by hydrolysis or alcoholysis.

  The polymer solution containing the cyclic olefin ring-opening polymer having a hydroxyl group at the polymer chain end, obtained as described above, can be subjected to a reaction with an isocyanate compound in the same manner as described above.

  And after manufacturing the cyclic olefin ring-opening polymer which has a hydroxyl group in a polymer chain terminal in this way, the hydroxyl group of the cyclic olefin ring-opening polymer and the isocyanate group of an isocyanate compound are made to react, and urethane is made. By forming a linking group, a terminally modified group-containing cyclic olefin ring-opening polymer having an oxysilyl-urethane structure can be obtained.

The isocyanate compound used in this case is not particularly limited as long as it is a compound containing at least one oxysilyl group and one isocyanate group in the molecule. As a compound which contains an oxysilyl group and an isocyanate group in a molecule | numerator, the compound represented by following General formula (3) can be mentioned, for example.
^{O = C = N-Z-} Si (OR 3) y (R 4) 3-y (3)
(In the general formula (3), ^{R 3} and ^{R 4} represents a hydrocarbon group having 1 to 20 carbon atoms, Z is the .y is 1 to 3 represents a divalent hydrocarbon group having 1 to 20 carbon atoms integer .)

  Among the compounds represented by the general formula (3), particularly preferably used compounds include 2- (trimethoxysilyl) ethyl isocyanate, 3- (trimethoxysilyl) propyl isocyanate, and 4- (trimethoxysilyl) butyl isocyanate. , 6- (trimethoxysilyl) hexyl isocyanate, 8- (trimethoxysilyl) octyl isocyanate, 2- (triethoxysilyl) ethyl isocyanate, 3- (triethoxysilyl) propyl isocyanate, 4- (triethoxysilyl) butyl isocyanate , 6- (triethoxysilyl) hexyl isocyanate, 8- (triethoxysilyl) octyl isocyanate, 2- (dimethoxymethylsilyl) ethyl isocyanate, 3- (dimethoxymethylsilyl) propylisocyanate 4- (dimethoxymethylsilyl) butyl isocyanate, 2- (diethoxymethylsilyl) ethyl isocyanate, 3- (diethoxymethylsilyl) propyl isocyanate, 4- (diethoxymethylsilyl) butyl isocyanate, 2- (dimethoxy) Examples thereof include ethylsilyl) ethyl isocyanate, 2- (diethoxyethylsilyl) ethyl isocyanate, 2- (diethylmethoxysilyl) ethyl isocyanate, and 2- (dimethylethoxysilyl) ethyl isocyanate.

  The conditions for reacting the hydroxyl group of the cyclic olefin ring-opening polymer with the isocyanate group of the isocyanate compound are not particularly limited. For example, these are mixed in a solvent or under no solvent and heated to 20 to 200 ° C. It can be carried out. As a solvent in the case of using a solvent, the same solvent as the solvent used in the polymerization reaction can be used. Moreover, you may react by adding a urethane reaction catalyst to a reaction system as needed. There is no restriction | limiting in particular in the urethane reaction catalyst to be used, For example, metal catalysts, such as an organic tin compound (Dibutyltin dilaurate, dioctyltin dilaurate, etc.), a bismuth compound, base catalysts, such as an organic amine, and a DMC catalyst can be used.

  The reaction ratio between the hydroxyl group of the cyclic olefin ring-opening polymer and the isocyanate group of the isocyanate compound may be determined according to the introduction rate of the oxysilyl-urethane structure and the like, and is not particularly limited, but the molar ratio of hydroxyl group: isocyanate group is Usually, it is set in the range of 1: 1 to 1: 200, preferably in the range of 1: 1 to 1: 100.

  The content ratio of the terminal-modified group-containing cyclic olefin ring-opening polymer in the vibration-proof rubber composition of the present invention is the content ratio in all the rubber components contained in the vibration-proof rubber composition of the present invention. Preferably it is 10-70 weight%, More preferably, it is 20-70 weight%, More preferably, it is 30-60 weight%. If the content ratio of the terminal-modified group-containing cyclic olefin ring-opening polymer is too small, the dynamic ratio of the resulting rubber cross-linked product may increase, and the vibration-proof characteristics may decrease. May fall. In addition, the said content shall be calculated | required based on the weight of the polymer which comprises a rubber component, for example, shall exclude | exclude weights, such as extending oil.

<Silica>
The anti-vibration rubber composition of the present invention is obtained by blending the above-mentioned terminally modified group-containing cyclic olefin ring-opening polymer with silica having a nitrogen adsorption specific surface area of 100 m ² / g or less as measured by the BET method. It is.

  Such silica is not particularly limited, and for example, dry method white carbon, wet method white carbon, colloidal silica, precipitated silica and the like can be used. Among these, wet method white carbon mainly containing hydrous silicic acid is preferable. These may be used alone or in combination of two or more.

Further, the silica used in the present invention has a nitrogen adsorption specific surface area measured by the BET method of 100 m ² / g or less, preferably more than 60 m ² / g and 100 m ² / g or less, more preferably 65 It is -95 m < ² > / g, More preferably, it is 70-90 m < ² > / g. In the present invention, the above-mentioned terminally modified group-containing cyclic olefin ring-opening polymer is used in combination with silica having a nitrogen adsorption specific surface area measured by the BET method in the above range, and the content of silica will be described later. By setting it as a specific range, the obtained rubber cross-linked product can have a low dynamic magnification and excellent durability. In particular, by using silica having a nitrogen adsorption specific surface area measured by the BET method within the above range, the dispersibility of silica in the rubber composition can be enhanced, and thereby a rubber cross-linked product can be obtained. The storage elastic modulus (dynamic spring constant) can be reduced, and as a result, the dynamic magnification can be reduced. When the nitrogen adsorption specific surface area measured by the BET method is in the above range, the obtained rubber cross-linked product has a low dynamic ratio and excellent vibration-proof characteristics. The nitrogen adsorption specific surface area can be measured by the BET method in accordance with ASTM D3037-81.

  The silica used in the present invention may have a nitrogen adsorption specific surface area measured by the BET method in the above range, but the primary particle diameter is preferably in the range of 1 to 100 nm, more preferably 10 to 70 nm. More preferably, it is 20-50 nm. When the primary particle diameter is in the above range, the resulting rubber cross-linked product can have a lower dynamic magnification and be more excellent in vibration-proof properties.

  The compounding quantity of the silica in the vibration-proof rubber composition of this invention is 30-200 weight part with respect to 100 weight part of rubber components contained in the composition for vibration-proof rubber, Preferably it is 35-150. Part by weight, more preferably 40 to 120 parts by weight. If the amount of silica is too small, the durability of the resulting rubber cross-linked product will be deteriorated. On the other hand, if the amount is too large, it will be difficult to disperse the silica in the rubber component. (Spring constant) increases, and as a result, the dynamic magnification deteriorates.

<Natural rubber>
The vibration-proof rubber composition of the present invention preferably contains natural rubber as a rubber component in addition to the terminally modified group-containing cyclic olefin ring-opening polymer. By containing natural rubber, the durability of the resulting rubber cross-linked product can be further increased.

  The content ratio of the natural rubber in the vibration-proof rubber composition of the present invention is the content ratio in all rubber components contained in the vibration-proof rubber composition of the present invention, preferably 30 to 90% by weight. More preferably 30 to 80% by weight, still more preferably 40 to 70% by weight. By mix | blending natural rubber in the said ratio, durability of the rubber crosslinked material obtained can be improved more appropriately.

  In addition to the terminal-modified group-containing cyclic olefin ring-opening polymer and natural rubber, the composition for vibration-proof rubber of the present invention is a rubber other than the terminal-modified group-containing cyclic olefin ring-opening polymer and natural rubber. It may contain. Examples of the rubber other than the terminally modified group-containing cyclic olefin ring-opening polymer and natural rubber include, for example, polyisoprene rubber (IR), solution polymerization SBR (solution polymerization styrene butadiene rubber), emulsion polymerization SBR (emulsion polymerization styrene butadiene). Rubber), low cis BR (polybutadiene rubber), high cis BR, high trans BR (trans bond content of butadiene portion 70 to 95%), styrene-isoprene copolymer rubber, butadiene-isoprene copolymer rubber, emulsion-polymerized styrene- Acrylonitrile-butadiene copolymer rubber, acrylonitrile-butadiene copolymer rubber, polyisoprene-SBR block copolymer rubber, polystyrene-polybutadiene-polystyrene block copolymer, acrylic rubber, epichlorohydrin rubber, fluorine rubber, silicon rubber, ethyl - propylene rubber, and urethane rubber. These rubbers can be used alone or in combination of two or more.

  In the case of blending a rubber other than the terminal modified group-containing cyclic olefin ring-opening polymer and natural rubber, the content is the content ratio in the total rubber component contained in the vibration-proof rubber composition of the present invention, Preferably it is 60 weight% or less, More preferably, it is 50 weight% or less, More preferably, it is 30 weight% or less.

<Other ingredients>
The anti-vibration rubber composition of the present invention includes a crosslinking agent, a crosslinking accelerator, a crosslinking activator, a silane coupling agent, an anti-aging agent, an activator, a process oil, a plastic, in addition to the above components, according to a conventional method. A necessary amount of compounding agents such as an agent, a lubricant, a filler other than silica, a tackifier, and aluminum hydroxide can be added.

  Examples of the crosslinking agent include sulfur, sulfur halides, organic peroxides, quinonedioximes, organic polyvalent amine compounds, and alkylphenol resins having a methylol group. Of these, sulfur is preferably used. The amount of the crosslinking agent is preferably 0.1 to 15 parts by weight, more preferably 0.3 to 10 parts by weight, and still more preferably 0.00 to 100 parts by weight of the rubber component in the vibration-proof rubber composition. 5 to 5 parts by weight.

  Examples of the crosslinking accelerator include N-cyclohexyl-2-benzothiazolylsulfenamide, Nt-butyl-2-benzothiazolylsulfenamide, N-oxyethylene-2-benzothiazolylsulfenamide, Sulfenamide crosslinking accelerators such as N-oxyethylene-2-benzothiazolylsulfenamide and N, N′-diisopropyl-2-benzothiazolylsulfenamide; 1,3-diphenylguanidine, diortolylguanidine And guanidine-based crosslinking accelerators such as orthotolylbiguanidine; thiourea-based crosslinking accelerators; thiazole-based crosslinking accelerators; thiuram-based crosslinking accelerators; dithiocarbamic acid-based crosslinking accelerators; xanthogenic acid-based crosslinking accelerators. Among these, those containing a sulfenamide-based crosslinking accelerator are particularly preferable. These crosslinking accelerators are used alone or in combination of two or more. The amount of the crosslinking accelerator is preferably 0.1 to 15 parts by weight, more preferably 0.5 to 5 parts by weight, particularly preferably 1 with respect to 100 parts by weight of the rubber component in the vibration-proof rubber composition. 0.0 to 4.0 parts by weight.

  Examples of the crosslinking activator include higher fatty acids such as stearic acid and zinc oxide. The blending amount of the crosslinking activator is not particularly limited, but is preferably 0.05 to 10 parts by weight, more preferably 0.5 to 5 parts by weight with respect to 100 parts by weight of the rubber component in the vibration-proof rubber composition. Part.

  Examples of the silane coupling agent include vinyltriethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, N- (β-aminoethyl) -γ-aminopropyltrimethoxysilane, 3-octanoylthio- 1-propyl-triethoxysilane, bis (3- (triethoxysilyl) propyl) disulfide, bis (3- (triethoxysilyl) propyl) tetrasulfide, γ-trimethoxysilylpropyldimethylthiocarbamyl tetrasulfide, and γ -Trimethoxysilylpropyl benzothiazyl tetrasulfide etc. can be mentioned. Among these, from the viewpoint of avoiding scorch during kneading, those having 4 or less sulfur in one molecule are preferable. These silane coupling agents can be used alone or in combination of two or more. The amount of the silane coupling agent is preferably 0.1 to 30 parts by weight, more preferably 1 to 15 parts by weight, based on 100 parts by weight of silica.

  Examples of the process oil include paraffinic, aromatic, and naphthenic petroleum softeners; plant softeners; fatty acids.

  Examples of the filler other than silica include carbon black. Examples of carbon black include furnace black, acetylene black, thermal black, channel black, and graphite. Of these, furnace black is preferably used, and specific examples thereof include SAF, ISAF, ISAF-HS, ISAF-LS, IISAF-HS, HAF, HAF-HS, HAF-LS, MAF, and FEF. Can be mentioned. These may be used alone or in combination of two or more.

  In order to obtain the anti-vibration rubber composition of the present invention, each component may be kneaded according to a conventional method. For example, after kneading a compounding agent excluding a crosslinking agent and a crosslinking accelerator, silica, and a rubber component, The kneaded product can be mixed with a crosslinking agent and a crosslinking accelerator to obtain the desired composition. The kneading temperature of the compounding agent and the rubber component excluding the crosslinking agent and the crosslinking accelerator is preferably 80 to 200 ° C, more preferably 120 to 180 ° C. The kneading time is preferably 30 seconds to 30 minutes. Mixing of the kneaded material, the crosslinking agent and the crosslinking accelerator is usually performed after cooling to 100 ° C. or lower, preferably 80 ° C. or lower. In addition, when obtaining the composition for vibration-proof rubber of the present invention, a method of adding a compounding agent and silica to a solid rubber and kneading (dry kneading method), or a solution of a rubber with a compounding agent Any method of adding silica and solidifying and drying (wet kneading method) may be used.

<Rubber cross-linked product>
The rubber cross-linked product of the present invention can be obtained by cross-linking the above-described anti-vibration rubber composition of the present invention.

  The crosslinking method for crosslinking the vibration-proof rubber composition of the present invention is not particularly limited, and may be selected according to the shape and size of the rubber crosslinked product. The anti-vibration rubber composition may be filled in a mold and heated to crosslink at the same time as molding, or the pre-molded anti-vibration rubber composition may be crosslinked by heating. The crosslinking temperature is preferably 120 to 200 ° C, more preferably 140 to 180 ° C, and the crosslinking time is usually about 1 to 120 minutes.

  Since the rubber cross-linked product of the present invention is obtained using the above-described anti-vibration rubber composition of the present invention, the dynamic magnification is low and the durability is excellent. Therefore, taking advantage of such characteristics, it is suitably used as a vibration-proof rubber member. The anti-vibration rubber member is not particularly limited. For example, it is used for railway vehicles, generators, electric motors, automobiles, houses, etc., among them, various mounts such as engine mounts and liquid-filled mounts, various bushes, dampers, It is particularly preferably used for vibration-proof rubber members for automobiles such as support rubber and bearings.

  Hereinafter, although this invention is demonstrated based on a more detailed Example, this invention is not limited to these Examples. In the following, “part” is based on weight unless otherwise specified. Various tests and evaluations were performed according to the following methods.

[Molecular weight of cyclopentene ring-opening polymer]
The weight average molecular weight (Mw) and number average molecular weight (Mn) of the cyclopentene ring-opening polymer were measured as polystyrene equivalent values by gel permeation chromatography (GPC) using tetrahydrofuran as a solvent.

[Cis / trans ratio of cyclopentene ring-opening polymer]
^It was determined by ¹³ C-NMR spectrum measurement.

[Melting point (Tm) and glass transition temperature (Tg) of cyclopentene ring-opening polymer]
Using a differential scanning calorimeter (DSC), measurement was performed at a temperature increase of 10 ° C./min.

[Introduction rate of oxysilyl group in cyclopentene ring-opening polymer]
By measuring the ¹ H-NMR spectrum, the ratio between the peak integrated value derived from the oxysilyl group and the peak integrated value derived from the carbon-carbon double bond in the cyclopentene ring-opened polymer main chain was determined, and the ratio of this peak integrated value And the number average molecular weight (Mn) measured by GPC, the introduction rate of oxysilyl groups [(percentage of cyclopentene ring-opening polymer chain terminal / cyclopentene ring-opening polymer chain number into which oxysilyl group was introduced)] Calculated.

[Dynamic magnification evaluation]
A rubber composition as a sample was press-crosslinked at 160 ° C. for 20 minutes to prepare a test piece (rubber cross-linked product). A dynamic viscoelasticity tester (trade name “Eplexor 500N”, manufactured by GABO) was used for the test piece. ), The storage elastic modulus (E ′) at a test temperature of 60 ° C., a dynamic strain of 0.3%, and a frequency of 100 Hz was measured. Further, the obtained test piece was stretched by 25% at a test temperature of 23 ° C. and a tensile speed of 50 mm / min using a tensile tester (trade name “Strograph AE”, manufactured by Toyo Seiki Seisakusho) according to JIS K6254. The tensile stress at the time (σε) was measured. Based on the storage elastic modulus (E ′) and the tensile stress (σε) obtained as a result of the measurement, the dynamic magnification (E ′ / σε) was calculated. The obtained measurement result was an index with the measurement value of the reference sample (Comparative Example 1 described later) as 100. The larger this index is, the smaller the dynamic magnification is and the better the anti-vibration characteristics are.

[Durability evaluation]
A test piece (rubber cross-linked product) was produced by press-crosslinking the rubber composition as a sample at 160 ° C. for 20 minutes, and this test piece was subjected to a constant strain fatigue tester (trade name “FT” according to JIS K6270). -3100 "(manufactured by Ueshima Seisakusho Co., Ltd.), the number of repetitions until the test piece broke when a test strain of 200% was repeatedly applied to the test piece at a test temperature of 23 ° C was measured. The obtained measurement result was an index with the measurement value of the reference sample (Comparative Example 1 described later) as 100. The larger this index, the better the durability.

[Reference Example 1]
Preparation of diisobutylaluminum mono (n-hexoxide) / toluene solution (2.5% by weight) In a nitrogen atmosphere, 88 parts of toluene and 25.4% by weight of triisobutylaluminum / n were placed in a glass container containing a stirring bar. -7.8 parts of hexane solution (manufactured by Tosoh Finechem) was added. Subsequently, the container was cooled to −45 ° C., and 1.02 parts of n-hexanol (an equimolar amount with respect to triisobutylaluminum) was slowly added dropwise with vigorous stirring. Thereafter, the mixture was allowed to stand at room temperature while stirring to prepare a diisobutylaluminum mono (n-hexoxide) / toluene solution (2.5% by weight).

[Synthesis Example 1]
Under a nitrogen atmosphere, a glass container containing a stirrer was charged with 87 parts of a 1.0 wt% WCl ₆ / toluene solution and 2.5 wt% diisobutylaluminum mono (n-hexoxide) / toluene prepared in Reference Example 1. A catalyst solution was obtained by adding 43 parts of the solution and stirring for 15 minutes. In a nitrogen atmosphere, 300 parts of cyclopentene and 1.24 parts of 1,4-bis (triethoxysilyl) -2-butene were added to a pressure-resistant glass reaction vessel equipped with a stirrer, and the catalyst solution 130 prepared above was added thereto. The polymerization reaction was carried out at 25 ° C. for 4 hours. After the polymerization reaction for 4 hours, excess ethyl alcohol was added to the pressure resistant glass reaction vessel to stop the polymerization, and then the solution in the pressure resistant glass reaction vessel was dissolved in 2,6-di-t-butyl-p-cresol (BHT). ) Was poured into a large excess of ethyl alcohol. Next, the precipitated polymer was recovered, washed with ethyl alcohol, and then vacuum-dried at 40 ° C. for 3 days, thereby opening both ends-modified cyclopentene having triethoxysilyl groups at both ends of 78 parts of the polymer chain. A polymer (a1) was obtained.

  And about the obtained both terminal modified cyclopentene ring-opening polymer (a1), according to the said method, weight average molecular weight (Mw), cis / trans ratio, oxysilyl group introduction | transduction rate, melting | fusing point (Tm), and glass transition temperature (Tg) ) Was performed. The results are shown in Table 1.

[Synthesis Example 2]
Under a nitrogen atmosphere, a glass container containing a stirrer was charged with 87 parts of a 1.0 wt% WCl ₆ / toluene solution and 2.5 wt% diisobutylaluminum mono (n-hexoxide) / toluene prepared in Reference Example 1. A catalyst solution was obtained by adding 43 parts of the solution and stirring for 15 minutes. In a nitrogen atmosphere, 300 parts of cyclopentene and 0.96 parts of 1,4-bis (trimethoxysilyl) -2-butene were added to a pressure-resistant glass reaction vessel equipped with a stirrer, and the catalyst solution 130 prepared above was added thereto. The polymerization reaction was carried out at 25 ° C. for 24 hours. After the polymerization reaction for 24 hours, excess ethyl alcohol was added to the pressure-resistant glass reaction vessel to stop the polymerization, and then the solution in the pressure-resistant glass reaction vessel was treated with 2,6-di-t-butyl-p-cresol (BHT). ) Was poured into a large excess of ethyl alcohol. Next, the precipitated polymer was recovered, washed with ethyl alcohol, and then vacuum-dried at 40 ° C. for 3 days, thereby opening both ends modified cyclopentene having a trimethoxysilyl group at both ends of 90 parts of the polymer chain. A polymer (a2) was obtained.

  And about the obtained both terminal modified cyclopentene ring-opening polymer (a2), according to the said method, weight average molecular weight (Mw), cis / trans ratio, oxysilyl group introduction | transduction rate, melting | fusing point (Tm), and glass transition temperature (Tg) ) Was performed. The results are shown in Table 1.

[Synthesis Example 3]
Under a nitrogen atmosphere, 173 parts of toluene and 13.8 parts of a 25.4 wt% triisobutylaluminum / n-hexane solution (manufactured by Tosoh Finechem) were added to a glass container containing a stirrer. Subsequently, the container was cooled to −45 ° C., and 1.27 parts of 2-butene-1,4-diol (an equimolar amount with respect to triisobutylaluminum) was slowly added dropwise with vigorous stirring. Then, the reaction solution of triisobutylaluminum and 2-butene-1,4-diol was obtained by leaving it to room temperature while stirring.
Then, under a nitrogen atmosphere, in a pressure-resistant glass reaction vessel equipped with a stirrer, 87 parts of a 1.0 wt% WCl ₆ / toluene solution, and triisobutylaluminum and 2-butene-1,4-diol obtained as described above were obtained. 43 parts of the reaction product solution was added and stirred for 10 minutes, and then 0.39 parts of ethyl acetate was added and stirred for 10 minutes in order to adjust the cis / trans ratio of the resulting polymer. Subsequently, 300 parts of cyclopentene was added, and a polymerization reaction was performed at 25 ° C. for 24 hours. After the polymerization reaction, excess water-containing isopropanol was added to stop the polymerization, and the protected hydroxyl group was further deprotected. When the resulting solution was poured into a large excess of isopropanol, polymer precipitation occurred. The precipitated polymer was collected, washed with isopropanol, and then vacuum dried at 40 ° C. for 3 days to obtain 185 parts of a cyclopentene ring-opened polymer having hydroxyl groups at both ends of the polymer chain.

  Next, 100 parts of a cyclopentene ring-opening polymer having hydroxyl groups at both ends of the polymer chain obtained above and 1900 parts of toluene were added to a pressure-resistant glass reaction vessel equipped with a stirrer in a nitrogen atmosphere, The polymer is dissolved in toluene, 15 parts of 3- (triethoxysilyl) propyl isocyanate is further added, and the mixture is stirred at 100 ° C. for 6 hours, whereby the hydroxyl groups at the polymer chain ends and 3- (triethoxysilyl) propyl isocyanate are mixed. The urethane group was formed by reacting with an isocyanate group. After the completion of the reaction, the solution in the container was poured into a large excess of isopropanol containing 2,6-di-t-butyl-p-cresol (BHT), resulting in precipitation of the polymer. The precipitated polymer was collected, washed with isopropanol, and then vacuum-dried at 40 ° C. for 3 days to modify both ends having a triethoxysilyl group and an amino group at both ends of 70 parts of the polymer chain. A cyclopentene ring-opening polymer (a3) was obtained.

  And about the obtained both terminal modified cyclopentene ring-opening polymer (a3), according to the said method, a weight average molecular weight (Mw), cis / trans ratio, oxysilyl group introduction | transduction rate, melting | fusing point (Tm), and glass transition temperature (Tg) ) Was performed. The results are shown in Table 1.

[Synthesis Example 4]
Under a nitrogen atmosphere, a glass container containing a stirrer was charged with 87 parts of a 1.0 wt% WCl ₆ / toluene solution and 2.5 wt% diisobutylaluminum mono (n-hexoxide) / toluene prepared in Reference Example 1. A catalyst solution was obtained by adding 43 parts of the solution and stirring for 15 minutes. Then, under a nitrogen atmosphere, 300 parts of cyclopentene and 0.42 part of vinyl (triethoxy) silane were added to a pressure-resistant glass reaction vessel equipped with a stirrer, and 130 parts of the catalyst solution prepared above was added thereto. A time polymerization reaction was carried out. After the polymerization reaction for 4 hours, excess ethyl alcohol was added to the pressure resistant glass reaction vessel to stop the polymerization, and then the solution in the pressure resistant glass reaction vessel was dissolved in 2,6-di-t-butyl-p-cresol (BHT). ) Was poured into a large excess of ethyl alcohol. Next, the precipitated polymer was recovered, washed with ethyl alcohol, and vacuum-dried at 40 ° C. for 3 days to open one-end-modified cyclopentene having a triethoxysilyl group at the end of 76 parts of the polymer chain. A ring polymer (a4) was obtained.

  And about the obtained one terminal modified cyclopentene ring-opening polymer (a4), according to the said method, a weight average molecular weight (Mw), cis / trans ratio, oxysilyl group introduction | transduction rate, melting | fusing point (Tm), and glass transition temperature (Tg) ) Was performed. The results are shown in Table 1.

[Synthesis Example 5]
Under a nitrogen atmosphere, a glass container containing a stirrer was charged with 87 parts of a 1.0 wt% WCl ₆ / toluene solution and 2.5 wt% diisobutylaluminum mono (n-hexoxide) / toluene prepared in Reference Example 1. A catalyst solution was obtained by adding 43 parts of the solution and stirring for 15 minutes. Then, in a nitrogen atmosphere, 300 parts of cyclopentene, 200 parts of toluene, and 0.12 part of 1-hexene were added to a pressure-resistant glass reaction vessel equipped with a stirrer, and 130 parts of the catalyst solution prepared above was added thereto at 25 ° C. The polymerization reaction was carried out for 4 hours. After the polymerization reaction for 4 hours, excess ethyl alcohol was added to the pressure resistant glass reaction vessel to stop the polymerization, and then the solution in the pressure resistant glass reaction vessel was dissolved in 2,6-di-t-butyl-p-cresol (BHT). ) Was poured into a large excess of ethyl alcohol. Next, the precipitated polymer was collected, washed with ethyl alcohol, and vacuum-dried at 40 ° C. for 3 days to obtain 81 parts of an unmodified cyclopentene ring-opening polymer (a5).

  And about the obtained unmodified cyclopentene ring-opening polymer (a5), according to the above-mentioned method, weight average molecular weight (Mw), cis / trans ratio, oxysilyl group introduction rate, melting point (Tm), and glass transition temperature (Tg) Each measurement of was performed. The results are shown in Table 1.

[Example 1]
In a Brabender type mixer with a capacity of 250 ml, 30 parts of the both-end-modified cyclopentene ring-opening polymer (a1) obtained in Synthesis Example 1 and 70 parts of natural rubber (SMR-CV60) were masticated for 30 seconds, Silica having a nitrogen adsorption specific surface area of 90 m ² / g (trade name “Zeosil 1085GR” manufactured by Solvay, nitrogen adsorption specific surface area (BET method): 90 m ² / g, primary particle diameter 30 nm) 33.3 parts, process oil (JX Nippon Mining) 5 parts manufactured by Nisseki Energy Co., Ltd., trade name “Aromax T-DAE”), and silane coupling agent: bis-3-triethoxysilylpropyl tetrasulfide (trade name “Si69” manufactured by Evonik) 2.5 part was added and after 1.5 minutes kneading a starting temperature of 110 ° C., the nitrogen adsorption specific surface area ^90m 2 / g of silica (manufactured by Solvay 16.7 parts of trade name “Zeosil 1085GR”), 5 parts of carbon black (trade name “SEAST 7HM” manufactured by Tokai Carbon Co., Ltd.), 3 parts of zinc oxide, 2 parts of stearic acid, and anti-aging agent: N-phenyl-N 2 parts of '-(1,3-dimethylbutyl) -p-phenylenediamine (manufactured by Ouchi Shinsei Chemical Industry Co., Ltd., trade name “NOCRACK 6C”) is added and kneaded for 2.5 minutes. It was discharged. The temperature of the kneaded product at the end of kneading was 150 ° C. After the kneaded product was cooled to room temperature, it was kneaded again in a Brabender type mixer at 110 ° C. for 3 minutes, and then the kneaded product was discharged from the mixer. Next, with an open roll at 50 ° C., the obtained kneaded product, 1.4 parts of sulfur, crosslinking accelerator: N-tert-butyl-2-benzothiazolylsulfenamide (manufactured by Ouchi Shinsei Chemical Industry Co., Ltd., product) After kneading 1.2 parts of the name “Noxeller NS-P” and 1.2 parts of the crosslinking accelerator: 1,3-diphenylguanidine (trade name “Noxeller D” manufactured by Ouchi Shinsei Chemical Industry Co., Ltd.) A sheet-like rubber composition was obtained. And about the obtained rubber composition, according to the said method, dynamic magnification and durability were evaluated. The results are shown in Table 2.

[Example 2]
Except for using 30 parts of both-ends modified cyclopentene ring-opening polymer (a1) obtained in Synthesis Example 1 and 30 parts of both-ends modified cyclopentene ring-opening polymer (a2) obtained in Synthesis Example 2, A sheet-like rubber composition was obtained in the same manner as in Example 1. And about the obtained rubber composition, according to the said method, dynamic magnification and durability were evaluated. The results are shown in Table 2.

Example 3
Except for using 30 parts of both-ends modified cyclopentene ring-opening polymer (a1) obtained in Synthesis Example 3 instead of 30 parts of both-ends modified cyclopentene ring-opening polymer (a1) obtained in Synthesis Example 1, A sheet-like rubber composition was obtained in the same manner as in Example 1. And about the obtained rubber composition, according to the said method, dynamic magnification and durability were evaluated. The results are shown in Table 2.

Example 4
In place of 30 parts of the both-end modified cyclopentene ring-opening polymer (a1) obtained in Synthesis Example 1, except that 30 parts of the one-end modified cyclopentene ring-opening polymer (a4) obtained in Synthesis Example 4 was used, A sheet-like rubber composition was obtained in the same manner as in Example 1. And about the obtained rubber composition, according to the said method, dynamic magnification and durability were evaluated. The results are shown in Table 2.

Example 5
The blending amount of the both-end-modified cyclopentene ring-opening polymer (a1) obtained in Synthesis Example 1 was changed from 30 parts to 50 parts, and the blending amount of natural rubber (SMR-CV60) was changed from 70 parts to 50 parts. A sheet-like rubber composition was obtained in the same manner as in Example 1 except for the change. And about the obtained rubber composition, according to the said method, dynamic magnification and durability were evaluated. The results are shown in Table 2.

Example 6
The blending amount of the both-end-modified cyclopentene ring-opening polymer (a1) obtained in Synthesis Example 1 was changed from 30 parts to 10 parts, and the blending amount of natural rubber (SMR-CV60) was changed from 70 parts to 90 parts. A sheet-like rubber composition was obtained in the same manner as in Example 1 except for the change. And about the obtained rubber composition, according to the said method, dynamic magnification and durability were evaluated. The results are shown in Table 2.

[Comparative Example 1]
Instead of 30 parts of the both-end-modified cyclopentene ring-opening polymer (a1) obtained in Synthesis Example 1, polybutadiene rubber (manufactured by Nippon Zeon Co., Ltd., trade name “Nipol BR1220”, cis content 97%, Mooney viscosity (ML _{1 A} sheet-like rubber composition was obtained in the same manner as in Example 1 except that ₊₄ , 100 ° C) 43 and glass transition temperature (Tg)-110 ° C) 30 parts were used. And about the obtained rubber composition, according to the said method, dynamic magnification and durability were evaluated. The results are shown in Table 2.

[Comparative Example 2]
The procedure was carried out except that 30 parts of the unmodified cyclopentene ring-opening polymer (a5) obtained in Synthesis Example 5 was used in place of 30 parts of the both-end-modified cyclopentene ring-opening polymer (a1) obtained in Synthesis Example 1. A sheet-like rubber composition was obtained in the same manner as in Example 1. And about the obtained rubber composition, according to the said method, dynamic magnification and durability were evaluated. The results are shown in Table 2.

[Comparative Example 3]
Instead of 50 parts of silica with a nitrogen adsorption specific surface area of 90 m ² / g, silica with a nitrogen adsorption specific surface area of 165 m ² / g (product name “Zeosil 1165MP” manufactured by Solvay, nitrogen adsorption specific surface area (BET method): 160 m ² / g , Primary particle diameter 20 nm) A sheet-like rubber composition was obtained in the same manner as in Example 1 except that 50 parts were used. In Comparative Example 3, as in Example 1, when silica was added, divided addition was performed, and the addition ratio (ratio of divided addition) was also the same as in Example 1. And about the obtained rubber composition, according to the said method, dynamic magnification and durability were evaluated. The results are shown in Table 2.

[Comparative Example 4]
In a Brabender type mixer with a capacity of 250 ml, 30 parts of the both-end-modified cyclopentene ring-opening polymer (a1) obtained in Synthesis Example 1 and 70 parts of natural rubber (SMR-CV60) were masticated for 30 seconds, Silica with a nitrogen adsorption specific surface area of 90 m ² / g (manufactured by Solvay, trade name “Zeosil 1085GR”, nitrogen adsorption specific surface area (BET method): 90 m ² / g, primary particle diameter 30 nm), carbon black (manufactured by Tokai Carbon Co., Ltd.) , 13.3 parts of a trade name “Seast 7HM”), 5 parts of process oil (manufactured by JX Nippon Mining & Energy Corporation, trade name “Aromax T-DAE”), and silane coupling agent: bis-3-triethoxy 1 part of silylpropyltetrasulfide (trade name “Si69” manufactured by Evonik Co., Ltd.) is added, and 110 ° C. is used as a starting temperature. After kneading for 5 minutes, 21.7 parts of carbon black (trade name “SEAST 7HM”, manufactured by Tokai Carbon Co., Ltd.), 3 parts of zinc oxide, 2 parts of stearic acid, and anti-aging agent: N-phenyl-N ′-(1 , 3-dimethylbutyl) -p-phenylenediamine (manufactured by Ouchi Shinsei Chemical Industry Co., Ltd., trade name “NOCRACK 6C”) was further added and kneaded for 2.5 minutes, and the kneaded product was discharged from the mixer. The temperature of the kneaded product at the end of kneading was 150 ° C. After the kneaded product was cooled to room temperature, it was kneaded again in a Brabender type mixer at 110 ° C. for 3 minutes, and then the kneaded product was discharged from the mixer. Next, with an open roll at 50 ° C., the obtained kneaded product, 1.4 parts of sulfur, crosslinking accelerator: N-tert-butyl-2-benzothiazolylsulfenamide (manufactured by Ouchi Shinsei Chemical Industry Co., Ltd., product) After kneading 1.2 parts of the name “Noxeller NS-P” and 1.2 parts of a crosslinking accelerator: diphenylguanidine (trade name “Noxeller D” manufactured by Ouchi Shinsei Chemical Co., Ltd.), a sheet-like rubber A composition was obtained. And about the obtained rubber composition, according to the said method, dynamic magnification and durability were evaluated. The results are shown in Table 2.

As is apparent from the results shown in Tables 1 and 2, the terminal-modified group-containing cyclic olefin ring-opening polymer and silica having a specific surface area of 100 m ² / g or less are contained, and the silica content is determined according to the rubber composition. The rubber composition set to 30 to 200 parts with respect to 100 parts of the rubber component contained therein gave a rubber cross-linked product excellent in dynamic magnification and durability (Examples 1 to 6).
On the other hand, when a rubber composition comprising polybutadiene rubber is used in place of the terminal modified group-containing cyclic olefin ring-opening polymer, the resulting rubber cross-linked product is inferior in dynamic magnification and durability. (Comparative Example 1).
In addition, when a rubber composition formed by blending an unmodified cyclic olefin ring-opening polymer is used instead of the terminal-modified group-containing cyclic olefin ring-opening polymer, the resulting rubber cross-linked product has a dynamic magnification and The durability was inferior (Comparative Example 2).
Further, when a rubber composition containing silica having a specific surface area of more than 100 m ² / g was used, the obtained rubber cross-linked product was greatly inferior in durability (Comparative Example 3).
Also, when a rubber composition in which the amount of silica is less than 30 parts with respect to 100 parts of the rubber component contained in the rubber composition is used, the resulting rubber cross-linked product is greatly inferior in durability. (Comparative Example 4).

Claims (6)

An anti-vibration rubber composition comprising a terminal-modified group-containing cyclic olefin ring-opening polymer and silica having a nitrogen adsorption specific surface area of 100 m ² / g or less as measured by a BET method,
The composition for vibration-proof rubber whose content rate of the said silica is 30-200 weight part with respect to 100 weight part of rubber components contained in the said composition for vibration-proof rubber.   The anti-vibration rubber composition according to claim 1, wherein the terminal-modified group-containing cyclic olefin ring-opening polymer is a polymer in which an oxysilyl group is introduced at the end of a polymer chain.   The anti-vibration rubber composition according to claim 1 or 2, further comprising natural rubber as the rubber component.   The composition for vibration-proof rubber according to claim 3, wherein a content ratio of the natural rubber in the rubber component is 30 to 90% by weight.   A rubber cross-linked product obtained by cross-linking the vibration-proof rubber composition according to claim 1.   An anti-vibration rubber member comprising the rubber cross-linked product according to claim 5.