WO2017104423A1

WO2017104423A1 - Rubber composition and tire

Info

Publication number: WO2017104423A1
Application number: PCT/JP2016/085668
Authority: WO
Inventors: 慶一青松; 祥子菅江; 佑介廣川
Original assignee: 株式会社ブリヂストン
Priority date: 2015-12-15
Filing date: 2016-12-01
Publication date: 2017-06-22
Also published as: JPWO2017104423A1; JP6816919B2

Abstract

In the present invention, a rubber composition in which wear resistance and low heat-generating properties are obtained to a higher degree at the same time is provided through use of a rubber composition characterized by being obtained by blending a rubber component A including natural rubber and a modified conjugated diene (co)polymer having a glass transition temperature of -50°C or below, a rubber component B having a glass transition temperature of -35°C or higher, and a reinforcing filler, the modified conjugated diene (co)polymer having at a terminal end of the conjugated diene (co)polymer molecule a silanol group and a functional group which is near the silanol group and promotes reaction between the silanol group and the reinforcing filler, and two peaks based on the rubber component A and the rubber component B, respectively, being observed in a tan δ temperature dispersion curve obtained by a dynamic viscoelasticity test.

Description

Rubber composition and tire

The present invention relates to a rubber composition and a tire using the rubber composition that achieves a higher level of wet grip, low heat build-up, and wear resistance.

In recent years, due to social demands for reducing the burden on the global environment, demands for lower fuel consumption and longer life of automobiles are becoming more severe. In order to meet such demands, reduction of rolling resistance and improvement of wear resistance are also demanded for tire performance.
The most common technique for reducing the rolling resistance of tires is to improve the low heat build-up by using a material with less heat generation as a rubber composition, in addition to the technique by optimizing the tire structure. ing. As an example of this technique, a rubber composition in which silica is blended with a rubber component containing a block copolymer, a diene rubber that is incompatible with each other and a terminal-modified diene rubber for silica has been proposed (patent) Reference 1).

JP 2012-172000 A

The rubber composition described in Patent Document 1 can improve low rolling resistance and wear resistance. However, there is a demand for improving tire performance at a higher level. An object of the present invention is to provide a rubber composition capable of achieving both high wet grip properties, low heat generation properties, and wear resistance.

The gist of the present invention is as follows.
[1] A rubber component A containing natural rubber and a modified conjugated diene (co) polymer having a glass transition temperature of −50 ° C. or lower, a rubber component B having a glass transition temperature of −35 ° C. or higher, and a reinforcing filler. The modified conjugated diene (co) polymer is a silanol group at a molecular end of the conjugated diene (co) polymer, and a functional group in the vicinity of the silanol group, and the silanol group and the reinforcement Two peaks based on each of the rubber component A and the rubber component B are observed in the temperature dispersion curve of tan δ by a dynamic viscoelasticity test. The rubber composition characterized by the above-mentioned.
[2] The rubber composition according to [1], wherein the rubber component A is contained in an amount of 50% by mass or more based on the total mass of the rubber component A and the rubber component B.
[3] The rubber composition according to [1] or [2], wherein the ratio of the natural rubber in the rubber component A is 10% by mass or more and 80% by mass or less based on the total mass of the rubber component A.
[4] A tire comprising the rubber composition according to any one of [1] to [3].

According to the present invention, it is possible to provide a rubber composition in which wet grip properties, low heat build-up properties, and wear resistance are more highly compatible.

[Rubber composition]
A rubber composition according to an embodiment of the present invention includes a rubber component A containing natural rubber and a modified conjugated diene (co) polymer having a glass transition temperature of −50 ° C. or lower, and a rubber component having a glass transition temperature of −35 ° C. or higher. B and a reinforcing filler are blended, and the modified conjugated diene (co) polymer has a silanol group at the molecular end of the conjugated diene (co) polymer and a functional group in the vicinity of the silanol group. And having a functional group that promotes the reaction between the silanol group and the reinforcing filler, and in the temperature dispersion curve of tan δ by a dynamic viscoelasticity test, the rubber component A and the rubber component B Two peaks based on each are observed.
The temperature dispersion curve of tan δ of the rubber component is as follows: strain 0.1%, frequency 45 Hz, measurement temperature range 65 ° C. to −100 ° C., using a viscoelasticity tester ARES manufactured by Rheometrics Co., Ltd. It can be measured at a rate of 1 ° C./min.

[Rubber component A]
The rubber component A applicable to the rubber composition according to this embodiment includes natural rubber and a modified conjugated diene (co) polymer having a glass transition temperature of −50 ° C. or lower.
The ratio of the natural rubber in the rubber component A is preferably 10% by mass or more and 80% by mass or less, and more preferably 40% by mass or more and 60% by mass or less based on the total mass of the rubber component A. When the ratio of the natural rubber in the rubber component A is in the above range, good low heat build-up can be obtained.
By including natural rubber in the rubber component A, it is possible to improve the wear resistance of a tire formed using the rubber composition.
Of the rubber component A, the glass transition temperature of the modified conjugated diene (co) polymer is −50 ° C. or lower, preferably −60 ° C. or lower. Furthermore, the glass transition temperature of the rubber component A is preferably set lower than the glass transition temperature of the rubber component B described later.
When silica is used as the reinforcing filler described later by including a modified conjugated diene (co) polymer in rubber component A, the dispersibility of silica in rubber component A is enhanced. The rubber component A having a relatively low glass transition point is dispersed. Thereby, the increase in tan δ at 60 ° C. caused by blending silica can be suppressed, and the rolling performance of a tire obtained using the rubber composition can be improved.
It is also known that the glass transition temperature increases when the amount of styrene and vinyl contained in the rubber component increases. The contribution to the increase in the glass transition temperature is considered to be greater for the styrene content than for the vinyl content. Therefore, in this embodiment, an index of (styrene amount + 1/2 vinyl amount) is used.
Based on the above viewpoint, the (styrene content + 1/2 vinyl content) of the modified conjugated diene (co) polymer applicable to the rubber composition according to this embodiment is preferably 35% by mass or less, and 20% by mass. % Or less is more preferable. If the amount of styrene + 1/2 vinyl in the modified conjugated diene (co) polymer is 35% by mass or less, the glass transition temperature of the modified conjugated diene (co) polymer can be set to −50 ° C. or less.
Moreover, if it has the said property, the rubber component A will show a peak in the temperature different from the rubber component B mentioned later in the temperature dispersion curve of tan-delta of a rubber composition. Further, since the rubber component A contains the modified conjugated diene (co) polymer, the reinforcing filler is unevenly distributed in the modified conjugated diene (co) polymer in the rubber component A, and is excellent in the rubber component A. Can be dispersed.
In the rubber composition according to this embodiment, the rubber component A is preferably contained in an amount of 50% by mass or more, more preferably 60% by mass or more, based on the total mass of the rubber component A and the rubber component B. More preferably, it is 80 mass% or more. From the viewpoint of maintaining the wear resistance of the rubber composition, the upper limit of the ratio of the rubber component A is 95% by mass.

<Modified conjugated diene (co) polymer having a glass transition temperature of −50 ° C. or lower>
Examples of the modified conjugated diene (co) polymer having a glass transition temperature of −50 ° C. or lower that can be used for the rubber component A of the rubber composition according to this embodiment include the following.
That is, the active site of the conjugated diene (co) polymer having an active site has a characteristic group that generates a silanol group by hydrolysis, and (i) an addition reaction or a substitution reaction in the active site in the vicinity of the characteristic group. Or a functional group that promotes the reaction between the silanol group and the reinforcing filler after the reaction, or (ii) the silanol group and the reinforcing filler A modification reaction step for reacting an organosilane compound having a functional group that promotes the reaction with, a hydrolysis step performed after completion of the modification reaction step, and preferably a condensation reaction for further condensation reaction in the presence of a condensation accelerator It is a (co) polymer produced through a reaction step.
In the present embodiment, it is preferable that the characteristic group that generates a silanol group by hydrolysis is an alkoxysilane group, and 10% or more of the characteristic group generates a silanol group by hydrolysis.
In addition, in this invention, what is described as a conjugated diene (co) polymer includes a conjugated diene polymer and a conjugated diene copolymer.

The characteristic group that generates a silanol group by hydrolysis needs to become a silanol group by reaction when reacting with a reinforcing filler, particularly silica, but if it is a silanol group from the beginning, the reactivity with silica is It becomes higher, and there is a great effect that dispersibility of silica in the rubber composition is improved and low exothermic property of the rubber composition is improved. Furthermore, when the characteristic group that generates a silanol group by hydrolysis is an alkoxy group, a volatile organic compound (VOC, particularly alcohol) is generated, but a silanol group is not generated.

In the present invention, “the functional group is present in the vicinity of a characteristic group that generates a silanol group” means that the functional group is preferably 1 to 20 carbon atoms from the characteristic group in the organosilane compound. Within the range (which may be through silicon atoms), more preferably within the range of 1 to 15 carbon atoms (may be through silicon atoms), and even more preferably within the range of 1 to 12 carbon atoms (silicon atoms) Particularly preferably in the range of 1 to 10 carbon atoms (may be via silicon atoms), more particularly preferably in the range of 1 to 5 carbon atoms (via silicon atoms). Is also good).
“Nearby” in the case of “silanol group and functional group in the vicinity of the silanol group” has the same meaning as above.

In this embodiment, the organosilane compound and the conjugated diene (co) deuterium are formed by performing (i) addition or substitution reaction on the active site in the vicinity of the characteristic group that generates a silanol group by hydrolysis. An organic compound having a functional group that binds a coalescence and promotes the reaction between the silanol group and the reinforcing filler after the reaction, or (ii) a functional group that promotes the reaction between the silanol group and the reinforcing filler The silane compound is preferably an organic silane compound represented by the following general formula (1) or the following general formula (2).

Here, R ¹ is a single bond or a divalent hydrocarbon group having 1 to 20 carbon atoms; R ² and R ³ are each independently a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms; —OL ¹ Is a hydrolyzable functional group that forms a silanol group with Si by hydrolysis; A ¹ binds the organosilane compound and the conjugated diene (co) polymer by performing an addition or substitution reaction on the active site; Further, it is a functional group that promotes the reaction between the silanol group and the reinforcing filler after the reaction, and m is an integer of 1 to 10. “R ¹ is a single bond” means, for example, that in the general formula (1), A ¹ and Si are directly bonded by a single bond. Hereinafter, the same applies to R ⁴ , R ⁵ , R ⁶ and A ⁴ .

Wherein, ^{R 4} represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms; hydrocarbon group for ^{R 5} and ^{R 6} are each independently a single bond, a hydrogen atom or a C 1-20; -OL ² represents a hydrolyzable A ² is a hydrolyzable functional group that generates a silanol group together with Si; and A ² is a functional group that reacts with the active site, or an addition or substitution reaction on the active site, thereby allowing the organosilane compound and the conjugated diene (co) heavy B and D are groups each independently containing at least one functional group that promotes the reaction between the silanol group and the reinforcing filler; p and q are each independently 0 to It is an integer of 5, (p + q) is 1 or more, and n is an integer of 1 to 10.

Here, as the hydrolyzable functional group that generates a silanol group together with Si by hydrolysis, for example, an alkoxy group having 1 to 20 carbon atoms, a phenoxy group, a benzyloxy group, —OM _{(1 / x), and the} like are preferable. Can be mentioned. Of these, an alkoxy group having 1 to 20 carbon atoms is more preferable, and an alkoxy group having 1 to 12 carbon atoms is particularly preferable. Specific examples of the alkoxy group having 1 to 20 carbon atoms include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, an n-butoxy group, and a tert-butoxy group.
In the above formula -OM _{(1 / x)} , M is a group 1 element excluding hydrogen (ie, alkali metal); a group 2-12 element; a group 13 element excluding boron; a group excluding carbon and silicon. Group 14 element: a metal atom selected from Group 15 elements and rare earth elements excluding nitrogen, phosphorus and arsenic, and x is the valence of the metal atom. Group 2 elements are Be, Mg and alkaline earth metals. Among these metal atoms, alkali metals, Mg, alkaline earth metals, Sn, Al, Ti, and Fe are more preferable, and Li, Na, K, Mg, Ca, Ba, Sn, Al, Ti, and Fe are particularly preferable. .

In the general formula (1), the organosilane compound and the conjugated diene (co) polymer are bonded by performing an addition or substitution reaction on the active site, and after the reaction, the silanol group and the reinforcing filling Examples of the functional group A ¹ that promotes the reaction with the material include (thio) epoxy group (including glycidoxy group), (thio) isocyanate group, nitrile group (cyano group), pyridyl group, N-alkylpyrrolidonyl Group, N-alkylimidazolyl group, N-alkylpyrazolyl group, (thio) ketone group, (thio) aldehyde group, imine residue, amide group, ketimine group, isocyanuric acid triester residue, Thio) carboxylic acid hydrocarbyl ester residue, residue of (thio) carboxylic acid metal salt having 1 to 20 carbon atoms, carboxylic acid anhydride having 1 to 20 carbon atoms Product residues, carboxylic acid halide residues having 1 to 20 carbon atoms, or carbonic acid dihydrocarbyl ester residues. The halogen of the carboxylic acid halide residue having 1 to 20 carbon atoms is preferably chlorine, bromine or fluorine. As the carboxylic anhydride residue having 1 to 20 carbon atoms, a maleic anhydride residue, a phthalic anhydride residue, an acetic anhydride residue and the like are preferable. These are groups that bind to the active site of the conjugated diene (co) polymer and also promote the reaction with silica.

In the general formula (2), a functional group that reacts with the active site or a functional group A ² that binds the organosilane compound and the conjugated diene (co) polymer by performing an addition or substitution reaction on the active site. As the following formula (2-a)
-R ^d SiX ₃ (2-a)
[Wherein, R ^d represents a single bond, a substituted or unsubstituted alkylene group having 1 to 10 carbon atoms, or —OR ^e (R ^e is a substituted or unsubstituted alkylene group having 1 to 10 carbon atoms); X represents a halogen atom or an alkoxy group having 1 to 10 carbon atoms, and a plurality of X may be the same or different. Or a (thio) epoxy group, (thio) isocyanate group, nitrile group, imidazolyl group, ketimine group, (thio) ketone group or protected primary or secondary amino group Can do.

In the production of the modified conjugated diene (co) polymer used in the present invention, the functional group A ² that reacts with the active site of the conjugated diene (co) polymer is a functional group that can chemically react with the active site. A ² is preferable, and examples thereof include an alkoxy group having 1 to 20 carbon atoms, a phenoxy group, a benzyloxy group, and a halogen group. An alkoxy group having 1 to 20 carbon atoms is more preferable, and an alkoxy group having 1 to 12 carbon atoms is particularly preferable. Specific examples of the alkoxy group having 1 to 20 carbon atoms include a methoxy group, an ethoxy group, a propyloxy group, an isopropyloxy group, an n-butoxy group, and a tert-butoxy group. As the halogen, chlorine, bromine or fluorine is preferable.

In the general formula (2), as the groups B and D containing at least one functional group that promotes the reaction between the silanol group and the reinforcing filler, each independently, for example, a primary amino group, a second amino group, Amino group, protected primary or secondary amino group, tertiary amino group, cyclic amino group, oxazolyl group, imidazolyl group, aziridinyl group, (thio) ketone group, (thio) aldehyde group, amide group, (thio) Epoxy group (including glycidoxy group), (thio) isocyanate group, nitrile group (cyano group), pyridyl group, N-alkylpyrrolidonyl group, N-alkylimidazolyl group, N-alkylpyrazolyl group, imino group, amide group , Ketimine group, imine residue, isocyanuric acid triester residue, (thio) carboxylic acid hydrocarbyl ester residue having 1 to 20 carbon atoms, carbon Residue of 1 to 20 (thio) carboxylic acid metal salt, carboxylic acid anhydride residue having 1 to 20 carbon atoms, carboxylic acid halide residue having 1 to 20 carbon atoms, dihydrocarbyl carbonate residue or general formula And a functional group represented by -EFG.
Here, E is an imino group, a divalent imine residue, a divalent pyridine residue or a divalent amide residue, F is an alkylene group having 1 to 20 carbon atoms, a phenylene group or an aralkylene having 8 to 20 carbon atoms Group G is primary amino group, secondary amino group, protected primary or secondary amino group, tertiary amino group, cyclic amino group, oxazolyl group, imidazolyl group, aziridinyl group, ketimine group, nitrile group (cyano Group), an amide group, a pyridine group or a (thio) isocyanate group.
Specific examples of the functional group represented by the general formula -EFFG include, for example, -NH-C ₂ H ₄ -NH ₂ , -NH-C ₂ H ₄ -N (CH ₃ ) ₂ , and these Examples thereof include a functional group in which —C ₂ H ₄ — is replaced with —C ₆ H ₁₂ — or a phenylene group.

In the general formula (2), the silicon-containing group in which a halogen atom or an alkoxy group is bonded to a silicon atom, and the —R ^d SiX ₃ group represented by the formula (2-a) are the activity of the conjugated diene (co) polymer. On the other hand, (thio) epoxy group, (thio) isocyanate group, nitrile group, imidazolyl group, ketimine group, (thio) ketone group or protected primary or secondary amino group is silica It is a group that promotes the reaction.

If a functional group that promotes the reaction between the silanol group and the reinforcing filler exists in the vicinity of the silanol group, the reinforcing filler, particularly the hydroxy group on the silica surface, the silanol group, and the silanol group react with the reinforcing filler. It can be considered that a stable structure is formed by the three atoms (oxygen atom, sulfur atom or nitrogen atom) having unpaired electrons in the functional group to be promoted, and the reactivity of the silanol group to silica is improved. Thereby, the low exothermic property of the rubber composition of the present invention using the modified conjugated diene (co) polymer of the present invention is improved.

A hydrocarbon having 1 to 20 carbon atoms which is R ⁵ when R ¹ , R ⁴ or p is 1 or R ⁶ when q is 1 in the above general formula (1) and (2) Specific examples of the group include methylene group, ethylene group, propane-1,3-diyl group, butane-1,3-diyl group, butane-1,4-diyl group, pentane-1,3-diyl group, pentane. -1,5-diyl group, hexane-1,3-diyl group, hexane-1,6-diyl group, heptane-1,3-diyl group, heptane-1,7-diyl group, octane-1,8- Examples thereof include a diyl group, a nonane-1,9-diyl group, a decane-1,10-diyl group, a cyclopentane-1,3-diyl group, and a cyclohexane-1,4-diyl group. Of these, the propane-1,3-diyl group is particularly preferred.
Here, R ⁵ when p is 0 and R ⁶ when q is 0 are a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms in the same manner as R ² and R ³ . That is, the valence of R ⁵ is (p + 1), and the valence of R ⁶ is (q + 1).

In the general formula (1) and the general formula (2), R ² , R ³ , p ⁵ is 0, or R ^{5 is} q 0 and R ⁶ is C 1-20 Specific examples of the monovalent hydrocarbon group include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, n-hexyl group, n -Heptyl group, n-octyl group, stearyl group and the like. Among these, a methyl group or an ethyl group is particularly preferable.

Specific examples of the organosilane compound represented by the above general formula (1) include (2-glycidoxyethyl) dimethylmethoxysilane, (2-glycidoxyethyl) diethylmethoxy as (thio) epoxy group-containing silane compounds. Silane, (2-glycidoxyethyl) dimethylethoxysilane, (2-glycidoxyethyl) diethylethoxysilane, (3-glycidoxypropyl) dimethylmethoxysilane, (3-glycidoxypropyl) diethylmethoxysilane, (3-glycidoxypropyl) dimethylethoxysilane, (3-glycidoxypropyl) diethylethoxysilane, 2- (3,4-epoxycyclohexyl) ethyl (dimethyl) methoxysilane, 2- (3,4-epoxycyclohexyl) ) Ethyl (diethyl) methoxysilane, 2- 3,4-epoxycyclohexyl) ethyl (dimethyl) ethoxysilane, an epoxy group in the 2- (3,4-epoxycyclohexyl) ethyl (diethyl) ethoxysilane, and these compounds may include those obtained by replacing the thioepoxy group. Among these, in particular, (3-glycidoxypropyl) dimethylmethoxysilane, (3-glycidoxypropyl) diethylmethoxysilane, 2- (3,4-epoxycyclohexyl) ethyl (dimethyl) methoxysilane and 2- ( 3,4-epoxycyclohexyl) ethyl (diethyl) methoxysilane is preferred.

Another specific example of the organic silane compound represented by the general formula (1) is N- (1,3-dimethylbutylidene) -3- (dimethylethoxysilyl)- 1-propanamine, N- (1,3-dimethylbutylidene) -3- (diethylethoxysilyl) -1-propanamine, N- (1-methylethylidene) -3- (dimethylethoxysilyl) -1-propane Amines, N- (1-methylethylidene) -3- (diethylethoxysilyl) -1-propanamine, N-ethylidene-3- (dimethylethoxysilyl) -1-propanamine, N-ethylidene-3- (diethylethoxy) Silyl) -1-propanamine, N- (1-methylpropylidene) -3- (dimethylethoxysilyl) -1-propan N- (1-methylpropylidene) -3- (diethylethoxysilyl) -1-propanamine, N- (4-N, N-dimethylaminobenzylidene) -3- (dimethylethoxysilyl) -1-propane Amines, N- (4-N, N-dimethylaminobenzylidene) -3- (diethylethoxysilyl) -1-propanamine, N- (cyclohexylidene) -3- (dimethylethoxysilyl) -1-propanamine, And N- (cyclohexylidene) -3- (diethylethoxysilyl) -1-propanamine. Among these, in particular, N- (1-methylpropylidene) -3- (dimethylethoxysilyl) -1-propanamine, N- (1-methylpropylidene) -3- (diethylethoxysilyl) -1-propane Amines, N- (1,3-dimethylbutylidene) -3- (dimethylethoxysilyl) -1-propanamine and N- (1,3-dimethylbutylidene) -3- (diethylethoxysilyl) -1-propane Amines are preferred.

As another specific example of the organosilane compound represented by the general formula (1), as an imino (amidine) group-containing compound, 1- [3- (dimethylethoxysilyl) propyl] -4,5-dihydroimidazole, -[3- (diethylethoxysilyl) propyl] -4,5-dihydroimidazole, 1- [3- (dimethylmethoxysilyl) propyl] -4,5-dihydroimidazole, 1- [3- (diethylmethoxysilyl) propyl ] -4,5-dihydroimidazole, 3- [10- (dimethylethoxysilyl) decyl] -4-oxazoline, 3- [10- (diethylethoxysilyl) decyl] -4-oxazoline, 3- (1-hexamethylene Imino) propyl (dimethylethoxy) silane, 3- (1-hexamethyleneimino) propyl (di) Tilethoxy) silane, (1-hexamethyleneimino) methyl (dimethylmethoxy) silane, (1-hexamethyleneimino) methyl (diethylmethoxy) silane, 1- [3- (dimethylethoxysilyl) propyl] -4,5-dihydro Imidazole, 1- [3- (diethylethoxysilyl) propyl] -4,5-dihydroimidazole, 1- [3- (dimethylmethoxysilyl) propyl] -4,5-dihydroimidazole and 1- [3- (diethylmethoxy) Silyl) propyl] -4,5-dihydroimidazole and the like, among which 3- (1-hexamethyleneimino) propyl (dimethylethoxy) silane, 3- (1-hexamethyleneimino) propyl (Diethylethoxy) silane, (1-hexamethyleneimino) me Ru (dimethylmethoxy) silane, (1-hexamethyleneimino) methyl (diethylmethoxy) silane, 1- [3- (dimethylethoxysilyl) propyl] -4,5-dihydroimidazole, 1- [3- (diethylethoxysilyl) ) Propyl] -4,5-dihydroimidazole, 1- [3- (dimethylmethoxysilyl) propyl] -4,5-dihydroimidazole and 1- [3- (diethylmethoxysilyl) propyl] -4,5-dihydroimidazole Can be preferably mentioned.

As another specific example of the organic silane compound represented by the general formula (1), as the carboxylic acid ester group-containing compound, (3-methacryloyloxypropyl) dimethylethoxysilane, (3-methacryloyloxypropyl) Diethylethoxysilane, (3-methacryloyloxypropyl) dimethylmethoxysilane, (3-methacryloyloxypropyl) diethylmethoxysilane, (3-methacryloyloxypropyl) dimethylisopropoxysilane, (3-methacryloyloxypropyl) diethyl Examples thereof include isopropoxysilane, and among these, (3-methacryloyloxypropyl) dimethylmethoxysilane and (3-methacryloyloxypropyl) diethylmethoxysilane are preferable.

Furthermore, as another specific example of the organic silane compound represented by the general formula (1), as the isocyanate group-containing compound, (3-isocyanatopropyl) dimethylmethoxysilane, (3-isocyanatopropyl) diethylmethoxysilane, (3-isocyanatopropyl) dimethylethoxysilane, (3-isocyanatopropyl) diethylethoxysilane, (3-isocyanatopropyl) dimethylisopropoxysilane, (3-isocyanatopropyl) diethylisopropoxysilane, etc. Of these, (3-isocyanatopropyl) dimethylethoxysilane and (3-isocyanatopropyl) diethylethoxysilane are preferred.

Another specific example of the organic silane compound represented by the above general formula (1) includes 3- (dimethylethoxy) silylpropylsuccinic anhydride, 3- (diethylethoxy) silyl as a carboxylic acid anhydride-containing compound. Propyl succinic anhydride, 3- (dimethylmethoxy) silylpropyl succinic anhydride, 3- (diethylmethoxy) silylpropyl succinic anhydride, and the like. Among these, 3- (dimethylethoxy) silyl is preferable. Propyl succinic anhydride and 3- (diethylethoxy) silylpropyl succinic anhydride.

Examples of the organosilane compound represented by the general formula (2) include a trialkylsilyl group in which ^a protecting group is represented by —SiR ^a R ^b R ^c (where R ^a , R ^b and R ^c are each independently a carbon number). And a hydrocarbyloxysilane compound having a protected primary amino group having two alkyl groups of 1 to 12 alkyl groups, preferably a methyl group, an ethyl group, a propyl group, a propyl group or a butyl group. Specific examples of the hydrocarbyloxysilane compound having a protected primary amino group include N, N-bis (trimethylsilyl) aminopropylmethyldimethoxysilane, N, N-bis (trimethylsilyl) aminopropylmethyldiethoxysilane, N Preferred examples include N, N-bis (trimethylsilyl) aminoethylmethyldimethoxysilane, N, N-bis (trimethylsilyl) aminoethylmethyldiethoxysilane, and the like. Among these, N, N-bis (trimethylsilyl) aminopropylmethyldimethoxysilane or N, N-bis (trimethylsilyl) aminopropylmethyldiethoxysilane is particularly preferable.

As another example of the organic silane compound represented by the general formula (2), a trialkylsilyl group (R ^a , R ^b and R ^c are the same as above) in which the protecting group is represented by —SiR ^a R ^b R ^c And a hydrocarbyloxysilane compound having a protected secondary amino group. Specific examples of the hydrocarbyloxysilane compound having a protected secondary amino group include N, N-methyl (trimethylsilyl) aminopropylmethyldimethoxysilane, N, N-ethyl (trimethylsilyl) aminopropylmethyldimethoxysilane, N, N N-methyl (trimethylsilyl) aminopropylmethyldiethoxysilane, N, N-ethyl (trimethylsilyl) aminopropylmethyldiethoxysilane, N, N-methyl (trimethylsilyl) aminoethylmethyldimethoxysilane, N, N-ethyl (trimethylsilyl) Preferred examples include aminoethylmethyldimethoxysilane, N, N-methyl (trimethylsilyl) aminoethylmethyldiethoxysilane, and N, N-ethyl (trimethylsilyl) aminoethylmethyldiethoxysilane. That.

Another specific example of the organosilane compound represented by the general formula (2) is, for example, N- (1,3-dimethylbutylidene) -3- (methyldiethoxysilyl) -1-propanamine, N- (1-methylethylidene) -3- (methyldiethoxysilyl) -1-propanamine, N-ethylidene-3- (methyldiethoxysilyl) -1-propanamine, N- (1-methylpropylidene) -3- (Methyldiethoxysilyl) -1-propanamine, N- (4-N, N-dimethylaminobenzylidene) -3- (methyldiethoxysilyl) -1-propanamine, N- (cyclohexylidene) -3- (methyldiethoxysilyl) -1-propanamine and methyldimethoxysilyl compounds corresponding to these methyldiethoxysilyl compounds, Preferable examples include imine residue-containing hydrocarbyloxysilane compounds such as tildiethoxysilyl compounds and ethyldimethoxysilyl compounds. Among these, N- (1-methylpropylidene) -3- (methyldiethoxy) is particularly preferable. Silyl) -1-propanamine and N- (1,3-dimethylbutylidene) -3- (methyldiethoxysilyl) -1-propanamine are preferred.

Further, other specific examples of the organic silane compound represented by the general formula (2) include, for example, 3-dimethylaminopropyl (diethoxy) methylsilane, 3-dimethylaminopropyl (dimethoxy) methylsilane, 3-diethylaminopropyl (diethoxy). Preferred examples include non-cyclic tertiary amino group-containing hydrocarbyloxysilane compounds such as methylsilane, 3-diethylaminopropyl (dimethoxy) methylsilane, 2-dimethylaminoethyl (diethoxy) methylsilane, and 2-dimethylaminoethyl (dimethoxy) methylsilane. Of these, 3-dimethylaminopropyl (dimethoxy) methylsilane and 3-dimethylaminopropyl (diethoxy) methylsilane are particularly preferred.

Other specific examples of the organic silane compound represented by the general formula (2) include, for example, 3-methylaminopropyl (diethoxy) methylsilane, 3-methylaminopropyl (dimethoxy) methylsilane, 3-ethylaminopropyl ( Preferred examples include non-cyclic secondary amino group-containing hydrocarbyloxysilane compounds such as diethoxy) methylsilane, 3-ethylaminopropyl (dimethoxy) methylsilane, 2-methylaminoethyl (diethoxy) methylsilane, 2-methylaminoethyl (dimethoxy) methylsilane, and the like. Of these, 3-methylaminopropyl (diethoxy) methylsilane and 3-methylaminopropyl (dimethoxy) methylsilane are particularly preferable.
As the acyclic primary amino group-containing hydrocarbyloxysilane compound, aminopropyl (diethoxy) methylsilane can be preferably used.

Other specific examples of the organic silane compound represented by the general formula (2) include, for example, 3- (1-hexamethyleneimino) propyl (methyldiethoxy) silane, 3- (1-hexamethyleneimino) Propyl (methyldimethoxy) silane, (1-hexamethyleneimino) methyl (methyldimethoxy) silane, (1-hexamethyleneimino) methyl (methyldiethoxy) silane, 2- (1-hexamethyleneimino) ethyl (methyldiethoxy) ) Silane, 2- (1-hexamethyleneimino) ethyl (methyldimethoxy) silane, 3- (1-pyrrolidinyl) propyl (methyldiethoxy) silane, 3- (1-pyrrolidinyl) propyl (methyldimethoxy) silane, 3- (1-heptamethyleneimino) propyl (methyldiethoxy) silane, -(1-dodecamethyleneimino) propyl (methyldiethoxy) silane, 3- (1-hexamethyleneimino) propyl (ethyldiethoxy) silane, 3- [10- (methyldiethoxysilyl) decyl] -4-oxazoline Preferred examples include cyclic tertiary amino group-containing hydrocarbyloxysilane compounds such as 3- (1-hexamethyleneimino) propyl (methyldiethoxy) silane and (1-hexamethyleneimino) methyl. (Methyldimethoxy) silane can be mentioned more preferably. In particular, 3- (1-hexamethyleneimino) propyl (methyldiethoxy) silane is preferred.

Another specific example of the organosilane compound represented by the general formula (2) is, for example, N- (3-methyldimethoxysilylpropyl) -4,5-dihydroimidazole, N- (3-methyldiethoxy Examples include amidine group-containing hydrocarbyloxysilane compounds such as (silylpropyl) -4,5-dihydroimidazole, and among these, N- (3-methyldiethoxysilylpropyl) -4,5-dihydroimidazole is preferable.

Other specific examples of the organosilane compound represented by the general formula (2) include, for example, (2-glycidoxyethyl) methyldimethoxysilane, (2-glycidoxyethyl) methyldiethoxysilane, ( 2-glycidoxyethyl) ethyldimethoxysilane, (2-glycidoxyethyl) ethyldiethoxysilane, (3-glycidoxypropyl) methyldimethoxysilane, (3-glycidoxypropyl) methyldiethoxysilane, ( 3-glycidoxypropyl) ethyldimethoxysilane, (3-glycidoxypropyl) ethyldiethoxysilane, 2- (3,4-epoxycyclohexyl) ethyl (methyldimethoxy) silane, 2- (3,4-exicyclohexyl) ) Ethyl (methyldiethoxy) silane 2- (3,4-epoxycyclohexyl) Preferred examples include epoxy group-containing hydrocarbyloxysilane compounds such as ethyl (ethyldimethoxy) silane and 2- (3,4-exicyclohexyl) ethyl (ethyldiethoxy) silane. Among these, (3) -Glycidoxypropyl) methyldimethoxysilane and (3-glycidoxypropyl) methyldiethoxysilane are preferred.
An epithio group-containing hydrocarbyloxysilane compound obtained by replacing the epoxy group of the epoxy group-containing hydrocarbyloxysilane compound with an epithio group can also be preferably exemplified.

Other specific examples of the organosilane compound represented by the general formula (2) include, for example, (3-isocyanatopropyl) methyldimethoxysilane, (3-isocyanatopropyl) methyldiethoxysilane, (3- Isocyanatopropyl) ethyldimethoxysilane, (3-isocyanatopropyl) ethyldiethoxysilane, (3-isocyanatopropyl) methyldiisopropoxysilane, 3- (isocyanatopropyl) ethyldiisopropoxysilane, etc. Examples thereof include hydrocarbyloxysilane compounds, among which (3-isocyanatopropyl) methyldiethoxysilane is preferred.

Other specific examples of the organic silane compound represented by the general formula (2) include, for example, 3-methacryloyloxypropylmethyldiethoxysilane, 3-methacryloyloxypropylmethyldimethoxysilane, and 3-methacryloyloxy. Examples include hydrocarbyloxysilane compounds containing carboxylic acid hydrocarbyl ester residues such as propylethyldimethoxysilane, 3-methacryloyloxypropylethyldiethoxysilane, and 3-methacryloyloxypropylmethyldiisopropoxysilane. Loyloxypropylmethyldimethoxysilane and 3-methacryloyloxypropylmethyldiethoxysilane are preferred.

Other specific examples of the organosilane compound represented by the general formula (2) include, for example, 3- (methyldiethoxysilyl) propyl succinic anhydride, 3- (methyldimethoxysilyl) propyl succinic anhydride Examples thereof include hydrocarbyloxysilane compounds containing carboxylic acid anhydride residues such as 3- (methyldiethoxysilyl) propyl succinic anhydride.
Further, 2- (methyldimethoxysilylethyl) pyridine, 2- (methyldiethoxysilylethyl) pyridine, 2-cyanoethylmethyldiethoxysilane and the like can be mentioned.

Of the various organic silane compounds represented by the above general formula (2), a hydrocarbyloxysilane compound having an amino group or an imine residue is preferable from the viewpoint of improving low heat build-up, and among them, the above-mentioned protected A hydrocarbyloxysilane compound having a primary amino group is particularly preferred. This is because introduction of a primary amino group into the molecular chain terminal of the modified conjugated diene (co) polymer greatly improves the low heat buildup of the rubber composition containing the modified conjugated diene (co) polymer.

In this embodiment, the method for producing a modified conjugated diene (co) polymer may optionally include hydrocarbyl at the active site of the conjugated diene (co) polymer before the modification reaction step of reacting the organosilane compound. A pre-denaturing reaction step of reacting the oxysilane compound may be further included.
Here, the hydrocarbyloxysilane compound used in the preliminary modification reaction step preferably has a plurality of hydrocarbyloxysilyl groups. Even if one hydrocarbyloxysilyl group is consumed by reaction with the active site of the conjugated diene (co) polymer, the remaining hydrocarbyloxysilyl group is used to produce the modified conjugated diene (co) polymer in the present invention. This is because the modification reaction step necessary for the above can be carried out.

Examples of the conjugated diene monomer used to obtain a conjugated diene (co) polymer that can be used in the production of a modified conjugated diene (co) polymer include 1,3-butadiene, isoprene, and 1,3-pentadiene. 2,3-dimethyl-1,3-butadiene, 2-phenyl-1,3-butadiene, 1,3-hexadiene and the like. These may be used alone or in combination of two or more. Of these, 1,3-butadiene is particularly preferred.
Examples of the aromatic vinyl monomer used in the conjugated diene (co) polymer include styrene, α-methylstyrene, 1-vinylnaphthalene, 3-vinyltoluene, ethylvinylbenzene, divinylbenzene, 4-cyclohexane. Examples include hexyl styrene and 2,4,6-trimethyl styrene. These may be used alone or in combination of two or more. Of these, styrene is particularly preferred.
The conjugated diene (co) polymer may be polybutadiene, polyisoprene, butadiene-isoprene copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer or styrene-isoprene-butadiene terpolymer. Among these, polybutadiene and styrene-butadiene copolymer are particularly preferable.

The styrene-butadiene copolymer that can be used as the conjugated diene (co) polymer preferably has a weight average molecular weight (Mw) before or after the modification reaction described later of 100,000 to 800,000. 150,000 to 700,000 is more preferable. By setting the weight average molecular weight within this range, the elastic modulus of the vulcanizate is reduced and the increase in hysteresis loss is suppressed to obtain excellent fracture resistance, and the rubber composition containing SBR has excellent kneading workability. can get. A weight average molecular weight is obtained by standard polystyrene conversion based on GPC method. The styrene-butadiene copolymer may be emulsion polymerization SBR or solution polymerization SBR.
The styrene-butadiene copolymer may be represented as SBR, and the modified styrene-butadiene copolymer may be represented as modified SBR.

The following method may be used for producing the modified styrene-butadiene copolymer. That is, in order to react and modify a hydrocarbyloxysilane compound, particularly a hydrocarbyloxysilane compound containing nitrogen and silicon, on the active terminal of the styrene-butadiene copolymer, the styrene-butadiene copolymer contains at least 10% polymer. The chain has a living property or pseudo-living property. As such a polymerization reaction having a living property, a reaction in which an organic alkali metal compound is used as an initiator and styrene and butadiene are anionically polymerized in an organic solvent is preferable. By anionic polymerization, a high conjugated diene moiety vinyl bond content can be obtained, and the glass transition temperature Tg can be adjusted to a desired temperature. Heat resistance can be improved by increasing the vinyl bond content, and fuel efficiency can be improved by increasing the cis-1,4 bond content.

As the organic alkali metal compound used as the initiator for the above-mentioned anionic polymerization, an organic lithium compound is preferable. The organolithium compound is not particularly limited, but hydrocarbyl lithium or lithium amide compound is preferably used. When the former hydrocarbyl lithium is used, it has a hydrocarbyl group at the polymerization initiation terminal and the other terminal has polymerization activity. A styrene-butadiene copolymer as a site is obtained, and the above-described hydrocarbyloxysilane compound is reacted with the active terminal as a polymerization active site to be modified.

When the latter lithium amide compound is used, a styrene-butadiene copolymer having a nitrogen-containing group at the polymerization initiation terminal and the other terminal being a polymerization active site is obtained. In the case of a lithium amide compound, the modified SBR according to the present invention can be obtained without modification with the above-described hydrocarbyloxysilane compound, but the hydrocarbyloxysilane compound, particularly nitrogen and silicon, are included at the active terminal that is the polymerization active site. When the hydrocarbyloxysilane compound is reacted and modified, a so-called both-end-modified styrene-butadiene copolymer can be obtained, and the dispersibility and reinforcing properties of fillers such as carbon black and silica can be further enhanced. preferable.

The hydrocarbyl lithium that is a polymerization initiator preferably has a hydrocarbyl group having 2 to 20 carbon atoms. For example, ethyl lithium, n-propyl lithium, isopropyl lithium, n-butyl lithium, sec-butyl lithium, tert-octyl lithium N-decyllithium, phenyllithium, 2-naphthyllithium, 2-butylphenyllithium, 4-phenylbutyllithium, cyclohexyllithium, cyclobenthyllithium, reaction product of diisopropenylbenzene and butyllithium, etc. Among these, n-butyllithium is particularly preferable.

Examples of the lithium amide compound as a polymerization initiator include lithium hexamethylene imide, lithium pyrrolidide, lithium piperide, lithium heptamethylene imide, lithium dodecamethylene imide, lithium dimethyl amide, lithium diethyl amide, lithium dibutyl amide, lithium Dipropylamide, lithium diheptylamide, lithium dihexylamide, lithium dioctylamide, lithium di-2-ethylhexylamide, lithium didecylamide, lithium-N-methylpiverazide, lithium ethylpropylamide, lithium ethylbutyramide, lithium ethylbenzylamide, Examples include lithium methylphenethylamide. Among these, from the viewpoint of the interaction effect on carbon black and the ability of initiating polymerization, cyclic lithium amides such as lithium hexamethylene imide, lithium pyrrolidide, lithium piperidide, lithium heptamethylene imide, and lithium dodecamethylene imide are preferable. In particular, lithium hexamethylene imide and lithium pyrrolidide are suitable.
As these lithium amide compounds, those prepared in advance from secondary amines and lithium compounds can be used for polymerization, but they can also be prepared in-polymerization in situ. The amount of the polymerization initiator used is preferably selected in the range of 0.2 to 20 mmol per 100 g of monomer.

A method for producing a styrene-butadiene copolymer by anionic polymerization using the organolithium compound as a polymerization initiator is not particularly limited, and a conventionally known method can be used.
Specifically, the lithium compound is polymerized with a conjugated diene compound and an aromatic vinyl compound in an organic solvent inert to the reaction, for example, a hydrocarbon solvent such as an aliphatic, alicyclic or aromatic hydrocarbon compound. A styrene-butadiene copolymer having a target active end can be obtained by anionic polymerization in the presence of a randomizer used as an initiator, if desired.

The hydrocarbon solvent is preferably one having 3 to 8 carbon atoms. For example, propane, n-butane, isobutane, n-pentane, isopentane, n-hexane, cyclohexane, propene, 1-butene, isobutene, trans-2 -Butene, cis-2-butene, 1-pentene, 2-pentene, 1-hexene, 2-hexene, benzene, toluene, xylene, ethylbenzene and the like. These may be used alone or in combination of two or more.
The monomer concentration in the solution is preferably 5 to 50% by mass, more preferably 10 to 30% by mass. When copolymerization is performed using a conjugated diene compound and an aromatic vinyl compound, the content of the aromatic vinyl compound in the charged monomer mixture is preferably 5 to 55% by mass, more preferably 6 to 45% by mass. .

The randomizer used as desired is control of the microstructure of the styrene-butadiene copolymer, such as an increase in 1,2 bonds in the butadiene portion in the butadiene-styrene copolymer, an increase in 3,4 bonds in the isoprene polymer, etc. Or a compound having an action of controlling the composition distribution of monomer units in a conjugated diene-aromatic vinyl copolymer, for example, randomizing butadiene units or styrene units in a butadiene-styrene copolymer.
As this randomizer, any one of known compounds generally used as a conventional randomizer can be appropriately selected and used. Specifically, dimethoxybenzene, tetrahydrofuran, dimethoxyethane, diethylene glycol dibutyl ether, diethylene glycol dimethyl ether, 2,2-bis (2-tetrahydrofuryl) -propane, triethylamine, pyridine, N-methylmorpholine, N, N, N ′, Mention may be made of ethers such as N′-tetramethylethylenediamine and 1,2-dipiperidinoethane, and tertiary amines. Further, potassium salts such as potassium t-amylate and potassium t-butoxide, and sodium salts such as sodium t-amylate can also be used.

One of these randomizers may be used alone, or two or more thereof may be used in combination. The amount used is preferably selected in the range of 0.01 to 1000 molar equivalents per mole of lithium compound.
The temperature in this polymerization reaction is preferably selected in the range of 0 to 150 ° C, more preferably 20 to 130 ° C. The polymerization reaction can be carried out under generated pressure, but it is usually desirable to operate at a pressure sufficient to keep the monomer in a substantially liquid phase. That is, the pressure depends on the particular material being polymerized, the polymerization medium used and the polymerization temperature, but higher pressures can be used if desired, such pressure being a gas that is inert with respect to the polymerization reaction. Can be obtained by an appropriate method such as pressurizing.

Next, a polymerization catalyst system for coordination anion polymerization will be described. As a polymerization catalyst system for coordination anionic polymerization, a catalyst containing a lanthanum series rare earth element compound in an organic solvent is used.
As a catalyst containing a lanthanum series rare earth element compound,
A component: a rare earth element-containing compound having an atomic number of 57 to 71 in the periodic table, or a reaction product of these compounds with a Lewis base,
Component B: the following general formula (5):
AlR ⁷ R ⁸ R ⁹ (5)
(Wherein R ⁷ and R ⁸ are the same or different and are a hydrocarbyl group having 1 to 10 carbon atoms or a hydrogen atom, and R ⁹ is a hydrocarbyl group having 1 to 10 carbon atoms, provided that R ⁹ is R ⁷ or And may be the same as or different from R ⁸ ), and C component: a complex compound of Lewis acid, metal halide and Lewis base, and an organic compound containing an active halogen. It is preferred to polymerize the conjugated diene monomer using a catalyst system.

In the present invention, it is preferable to add an organoaluminum oxy compound, so-called aluminoxane as a D component to the catalyst system containing the lanthanum series rare earth element compound in addition to the A component to the C component. Here, it is more preferable that the catalyst system is preliminarily prepared in the presence of the component A, component B, component C, component D and conjugated diene monomer.

In the present invention, the component A of the catalyst system containing the lanthanum series rare earth element compound is a compound containing a rare earth element having an atomic number of 57 to 71 in the periodic table, or a reaction product of these compounds with a Lewis base. Here, among the rare earth elements having atomic numbers of 57 to 71, neodymium, praseodymium, cerium, lanthanum, gadolinium, samarium, or a mixture thereof is preferable, and neodymium is particularly preferable.

The rare earth element-containing compound is preferably a salt soluble in a hydrocarbon solvent, and specific examples include carboxylates, alkoxides, β-diketone complexes, phosphates and phosphites of the rare earth elements. Of these, carboxylates and phosphates are preferable, and carboxylates are particularly preferable.
Here, examples of the hydrocarbon solvent include saturated aliphatic hydrocarbons having 4 to 10 carbon atoms such as butane, pentane, hexane and heptane, saturated alicyclic hydrocarbons having 5 to 20 carbon atoms such as cyclopentane and cyclohexane, -Monoolefins such as butene, 2-butene, aromatic hydrocarbons such as benzene, toluene, xylene, methylene chloride, chloroform, trichloroethylene, perchloroethylene, 1,2-dichloroethane, chlorobenzene, bromobenzene, chlorotoluene, etc. A halogenated hydrocarbon is mentioned.

As the rare earth element carboxylate, the following general formula (6):
^{_{_{^{(R 10 -CO 2) 3 M}}}} 1 ··· (6)
(Wherein R ¹⁰ is a hydrocarbyl group having 1 to 20 carbon atoms, and M ¹ is a rare earth element having an atomic number of 57 to 71 in the periodic table). Here, R ¹⁰ may be saturated or unsaturated, is preferably an alkyl group or an alkenyl group, and may be linear, branched, or cyclic. The carboxyl group is bonded to a primary, secondary or tertiary carbon atom. As the carboxylate, specifically, octanoic acid, 2-ethylhexanoic acid, oleic acid, neodecanoic acid, stearic acid, benzoic acid, naphthenic acid, versatic acid [trade names of Shell Chemical Co., Ltd. , A carboxylic acid in which a carboxyl group is bonded to a tertiary carbon atom] and the like. Among these, salts of 2-ethylhexanoic acid, neodecanoic acid, naphthenic acid, and versatic acid are preferable.

As the alkoxide of the rare earth element, the following general formula (7):
(R ¹¹ O) ₃ M ² (7)
(Wherein R ¹¹ is a hydrocarbyl group having 1 to 20 carbon atoms, and M ² is a rare earth element having an atomic number of 57 to 71 in the periodic table). Examples of the alkoxy group represented by R ¹¹ O include 2-ethyl-hexyloxy group, oleyloxy group, stearyloxy group, phenoxy group, benzyloxy group and the like. Of these, 2-ethyl-hexyloxy group and benzyloxy group are preferable.

Examples of the rare earth element β-diketone complex include the rare earth element acetylacetone complex, benzoylacetone complex, propionitrileacetone complex, valerylacetone complex, and ethylacetylacetone complex. Among these, an acetylacetone complex and an ethylacetylacetone complex are preferable.

Examples of the rare earth element phosphate and phosphite include the rare earth element, bis (2-ethylhexyl) phosphate, bis (1-methylheptyl phosphate), bis (p-nonylphenyl) phosphate, phosphorus Bis (polyethylene glycol-p-nonylphenyl), phosphoric acid (1-methylheptyl) (2-ethylhexyl), phosphoric acid (2-ethylhexyl) (p-nonylphenyl), 2-ethylhexylphosphonic acid mono-2-ethylhexyl 2-ethylhexylphosphonic acid mono-p-nonylphenyl, bis (2-ethylhexyl) phosphinic acid, bis (1-methylheptyl) phosphinic acid, bis (p-nonylphenyl) phosphinic acid, (1-methylheptyl) (2 -Ethylhexyl) phosphinic acid, (2-ethylhexyl) (p-nonylphenyl) phos And salts with phosphoric acid and the like. Among these, the rare earth elements, bis (2-ethylhexyl) phosphate, bis (1-methylheptyl) phosphate, mono-2-ethylhexyl 2-ethylhexylphosphonate, A salt with bis (2-ethylhexyl) phosphinic acid is preferred.

Among the rare earth element-containing compounds, neodymium phosphate and neodymium carboxylate are more preferable, and in particular, neodymium branching such as neodymium 2-ethylhexanoate, neodymium neodecanoate, neodymium versatate, etc. Carboxylate is most preferred.

The component A may be a reaction product of the rare earth element-containing compound and a Lewis base. The reaction product has improved solubility of the rare earth element-containing compound in the solvent due to the Lewis base, and can be stably stored for a long period of time. In order to easily solubilize the rare earth element-containing compound in a solvent and to store it stably for a long period of time, the Lewis base is used in a proportion of 0 to 30 mol, preferably 1 to 10 mol, per mol of the rare earth element. Or as a mixture of the two or as a product obtained by reacting both in advance. Here, examples of the Lewis base include acetylacetone, tetrahydrofuran, pyridine, N, N-dimethylformamide, thiophene, diphenyl ether, triethylamine, an organic phosphorus compound, and a monovalent or divalent alcohol.

The above-mentioned rare earth element-containing compounds as the component A or the reaction product of these compounds with a Lewis base can be used singly or as a mixture of two or more.

In the present invention, the organoaluminum compound represented by the above general formula (5) which is the B component of the catalyst system used for the polymerization of the terminal active polymer includes trimethylaluminum, triethylaluminum, tri-n-propylaluminum, triisopropyl Aluminum, tri-n-butylaluminum, triisobutylaluminum, tri-t-butylaluminum, tripentylaluminum, trihexylaluminum, tricyclohexylaluminum, trioctylaluminum; diethylaluminum hydride, di-n-propylaluminum hydride, Di-n-butylaluminum hydride, diisobutylaluminum hydride, dihexylaluminum hydride, diisohexylaluminum hydride, dioctylaluminum hydride, hydrogenated dii Octyl aluminum, ethyl aluminum dihydride, n- propyl aluminum dihydride, include isobutyl aluminum dihydride and the like, among these, triethylaluminum, triisobutylaluminum, hydrogenated diethylaluminum, hydrogenated diisobutylaluminum are preferred. The organoaluminum compound as component B described above can be used alone or in combination of two or more.

In the present invention, the component C of the catalyst system used for the polymerization of the terminal active polymer is at least one selected from the group consisting of Lewis acids, complex compounds of metal halides and Lewis bases, and organic compounds containing active halogens. Halogen compound.

The Lewis acid has Lewis acidity and is soluble in hydrocarbons. Specifically, methyl aluminum dibromide, methyl aluminum dichloride, ethyl aluminum dibromide, ethyl aluminum dichloride, butyl aluminum dibromide, butyl aluminum dichloride, dimethyl aluminum bromide, dimethyl aluminum chloride, diethyl bromide Aluminum, diethylaluminum chloride, dibutylaluminum bromide, dibutylaluminum chloride, methylaluminum sesquibromide, methylaluminum sesquichloride, ethylaluminum sesquibromide, ethylaluminum sesquichloride, dibutyltin dichloride, aluminum tribromide, antimony trichloride, Examples include antimony pentachloride, phosphorus trichloride, phosphorus pentachloride, tin tetrachloride, and silicon tetrachloride. Among these, diethylaluminum chloride, sesquiethylaluminum chloride, ethylaluminum dichloride, diethylaluminum bromide, ethylaluminum sesquibromide, and ethylaluminum dibromide are preferable.
Alternatively, a reaction product of an alkylaluminum and a halogen such as a reaction product of triethylaluminum and bromine can be used.

The metal halide constituting the complex compound of the above metal halide and Lewis base includes beryllium chloride, beryllium bromide, beryllium iodide, magnesium chloride, magnesium bromide, magnesium iodide, calcium chloride, calcium bromide, iodine. Calcium chloride, barium chloride, barium bromide, barium iodide, zinc chloride, zinc bromide, zinc iodide, cadmium chloride, cadmium bromide, cadmium iodide, mercury chloride, mercury bromide, mercury iodide, manganese chloride, Manganese bromide, manganese iodide, rhenium chloride, rhenium bromide, rhenium iodide, copper chloride, copper iodide, silver chloride, silver bromide, silver iodide, gold chloride, gold iodide, gold bromide, etc. Of these, magnesium chloride, calcium chloride, barium chloride, manganese chloride, zinc chloride, and copper chloride are preferred. Ku, magnesium chloride, manganese chloride, zinc chloride, copper chloride being particularly preferred.

Further, as the Lewis base constituting the complex compound of the metal halide and Lewis base, a phosphorus compound, a carbonyl compound, a nitrogen compound, an ether compound, an alcohol, and the like are preferable. Specifically, tributyl phosphate, tri-2-ethylhexyl phosphate, triphenyl phosphate, tricresyl phosphate, triethylphosphine, tributylphosphine, triphenylphosphine, diethylphosphinoethane, diphenylphosphinoethane, acetylacetone, benzoylacetone , Propionitrile acetone, valeryl acetone, ethyl acetylacetone, methyl acetoacetate, ethyl acetoacetate, phenyl acetoacetate, dimethyl malonate, diethyl malonate, diphenyl malonate, acetic acid, octanoic acid, 2-ethyl-hexanoic acid, olein Acid, stearic acid, benzoic acid, naphthenic acid, versatic acid, triethylamine, N, N-dimethylacetamide, tetrahydrofuran, diphenyl ether, 2-ethyl-hexyl alcohol Examples include oleyl alcohol, stearyl alcohol, phenol, benzyl alcohol, 1-decanol, and lauryl alcohol. Among these, tri-2-ethylhexyl phosphate, tricresyl phosphate, acetylacetone, 2-ethylhexanoic acid, versatic acid, 2 -Ethylhexyl alcohol, 1-decanol, lauryl alcohol are preferred.

The above Lewis base is usually reacted at a ratio of 0.01 to 30 mol, preferably 0.5 to 10 mol, per 1 mol of the metal halide. When the reaction product with the Lewis base is used, the metal remaining in the polymer can be reduced.
Examples of the organic compound containing the active halogen include benzyl chloride.

Examples of the D component aluminoxane include methylaluminoxane, ethylaluminoxane, propylaluminoxane, butylaluminoxane, chloroaluminoxane, and the like. By adding aluminoxane as the D component, the molecular weight distribution becomes sharp and the activity as a catalyst is improved.

The amount or composition ratio of each component of the catalyst system used in the present invention is appropriately selected according to its purpose or necessity. Of these, the component A is preferably used in an amount of 0.00001 to 1.0 mmol, more preferably 0.0001 to 0.5 mmol, per 100 g of 1,3-butadiene. By setting the amount of component A used within the above range, excellent polymerization activity can be obtained, and the need for a deashing step is eliminated.
The ratio of the A component to the B component is a molar ratio, and the A component: B component is usually 1: 1 to 1: 700, preferably 1: 3 to 1: 500.
Further, the ratio of the halogen in the A component and the C component is, as a molar ratio, usually 1: 0.1 to 1:30, preferably 1: 0.2 to 1:15, more preferably 1: 2.0 to 1: 5.0.
Further, the ratio of aluminum to the A component in the D component is usually 1: 1 to 700: 1, preferably 3: 1 to 500: 1 in terms of molar ratio. By making the amount of these catalysts within the range of the component ratio, it is preferable because it acts as a highly active catalyst and there is no need for a step of removing the catalyst residue.
In addition to the above components A to C, the polymerization reaction may be carried out in the presence of hydrogen gas for the purpose of adjusting the molecular weight of the polymer.

As a catalyst component, in addition to the above-mentioned A component, B component, C component, and D component used as necessary, a small amount of a conjugated diene monomer such as 1,3-butadiene is optionally added. You may use it in the ratio of 0-1000 mol per 1 mol of compounds of a component. A conjugated diene monomer such as 1,3-butadiene as a catalyst component is not essential, but when used in combination, there is an advantage that the catalytic activity is further improved.

In the production of the catalyst, for example, the A component to the C component are dissolved in a solvent, and a conjugated diene monomer such as 1,3-butadiene is reacted as necessary.
In that case, the addition order of each component is not specifically limited, Furthermore, you may add aluminoxane as D component. From the viewpoint of improving the polymerization activity and shortening the polymerization initiation induction period, it is preferable that these components are mixed in advance, reacted and aged.
Here, the aging temperature is about 0 to 100 ° C., preferably 20 to 80 ° C. When the temperature is less than 0 ° C., the aging is not sufficiently performed, and when the temperature exceeds 100 ° C., the catalytic activity may be reduced or the molecular weight distribution may be broadened.
The aging time is not particularly limited, and can be ripened by contacting in the line before adding to the polymerization reaction tank. Usually, 0.5 minutes or more is sufficient, and stable for several days.

In the production of the conjugated diene (co) polymer having terminal activity, a conjugated diene monomer alone or a conjugated diene monomer is used in an organic solvent using a catalyst system containing the lanthanum series rare earth element-containing compound. It can be obtained by solution polymerization of other conjugated diene monomers. Here, an inert organic solvent is used as the polymerization solvent. Examples of the inert organic solvent include saturated aliphatic hydrocarbons having 4 to 10 carbon atoms such as butane, pentane, hexane and heptane, saturated alicyclic hydrocarbons having 5 to 20 carbon atoms such as cyclopentane and cyclohexane, 1- Monoolefins such as butene and 2-butene, aromatic hydrocarbons such as benzene, toluene and xylene, methylene chloride, chloroform, carbon tetrachloride, trichloroethylene, perchloroethylene, 1,2-dichloroethane, chlorobenzene, bromobenzene, chloro And halogenated hydrocarbons such as toluene.
Among these, aliphatic hydrocarbons and alicyclic hydrocarbons having 5 to 6 carbon atoms are particularly preferable. These solvents may be used alone or in a combination of two or more.
The monomer concentration in the solution used for this coordinated anionic polymerization is preferably 5 to 50% by mass, more preferably 10 to 30% by mass.

In the present invention, the temperature in the coordination anion polymerization reaction is preferably selected in the range of −80 to 150 ° C., more preferably −20 to 120 ° C. The polymerization reaction can be carried out under generated pressure, but it is usually desirable to operate at a pressure sufficient to keep the monomer in a substantially liquid phase. That is, the pressure depends on the particular material being polymerized, the polymerization medium used and the polymerization temperature, but higher pressures can be used if desired, such pressure being a gas that is inert with respect to the polymerization reaction. Can be obtained by an appropriate method such as pressurizing.

In the case of modifying the active end of the conjugated diene (co) polymer having an active end obtained by the coordinated anionic polymerization reaction, the hydrocarbyloxysilane compound is reacted in advance in the above-described pre-modification reaction step, followed by hydrolysis. And (i) an organic silane compound and the conjugated diene (co) polymer are bonded to each other by performing an addition or substitution reaction on the active site in the vicinity of the characteristic group. It is modified by reacting an organosilane compound having a functional group that promotes the reaction between the silanol group and the reinforcing filler or (ii) a functional group that promotes the reaction between the silanol group and the reinforcing filler. This is preferable from the viewpoint of smoothly promoting the reaction.

In the above-mentioned anionic polymerization and coordination anionic polymerization, all the raw materials involved in the polymerization such as polymerization initiator, solvent, monomer, and the like have removed reaction inhibitors such as water, oxygen, carbon dioxide, and protic compounds. It is desirable to use one.
The polymerization reaction may be carried out either batchwise or continuously.
In this way, a conjugated diene (co) polymer having an active end is obtained.

In the modification reaction step of the method for producing a modified conjugated diene (co) polymer in the present invention, the conjugated diene (co) polymer having an active terminal obtained as described above is added to the above-described general formula (1) or The organosilane compound represented by the general formula (2) is preferably added in a stoichiometric amount or in excess to the active terminal of the conjugated diene (co) polymer and bonded to the polymer. React with active end.
The modification reaction step and the preliminary modification reaction step in the present invention are usually carried out under the same temperature and pressure conditions as in the polymerization reaction.

Next, the hydrolysis step of the method for producing a modified conjugated diene (co) polymer will be described. In the hydrolysis step, after completion of the modification reaction step, the hydrolysis reaction is performed under acidic, neutral or alkaline conditions in the presence of water. Thereby, the hydrolyzable functional group bonded to the modified conjugated diene (co) polymer is efficiently hydrolyzed, and a silanol group is generated at the terminal or side chain of the modified conjugated diene (co) polymer.
The amount of water used in this hydrolysis reaction is preferably an excess molar amount, for example, 2 to 4 times the molar amount of the initiator such as Li. The hydrolysis time is usually about 10 minutes to several hours.
When the hydrolysis reaction is performed under alkaline conditions, it is desirable to add an alkali metal hydroxide such as sodium hydroxide or potassium hydroxide, preferably sodium hydroxide as the basic compound, and the hydrolysis reaction under acidic conditions. In the case of carrying out, it is desirable to add as the acidic compound an inorganic acid such as hydrochloric acid, sulfuric acid or nitric acid, a carboxylic acid such as acetic acid or formic acid, silicon tetrachloride or the like.

In the present invention, a condensation reaction step for performing a condensation reaction in the presence of a condensation accelerator can be provided between the modification reaction step and the hydrolysis step or after the hydrolysis step.

The condensation accelerator used in the condensation reaction is preferably added after the modification reaction and before the start of the condensation reaction. When added before the denaturation reaction, a direct reaction with the active end may occur, and a hydrocarboxy group may not be introduced at the active end. Further, when added after the start of the condensation reaction, the condensation accelerator may not be uniformly dispersed and the catalyst performance may be lowered.
As the addition timing of the condensation accelerator, when a condensation reaction step is provided between the modification reaction step and the hydrolysis step, usually 5 minutes to 5 hours after the start of the modification reaction, preferably 15 minutes to 1 hour after the start of the modification reaction. Later. When a condensation reaction step is provided after the hydrolysis step, it is usually 5 minutes to 5 hours, preferably 10 minutes to 2 hours after the start of the hydrolysis reaction.

The condensation accelerator preferably contains a metal element, and more preferably a compound containing at least one metal belonging to Groups 2 to 15 of the periodic table.
The condensation accelerator containing the metal element preferably contains at least one selected from Ti, Sn, Bi, Zr and Al, and is an alkoxide, carboxylate or acetylacetonate complex of the metal. is there.

As the condensation accelerator containing Ti as a metal component, an alkoxide of titanium (Ti), a carboxylate, and an acetylacetonate complex salt are preferably used.
Specifically, tetrakis (2-ethyl-1,3-hexanediolato) titanium, tetrakis (2-methyl-1,3-hexanediolato) titanium, tetrakis (2-propyl-1,3-hexanediolato) ) Titanium, tetrakis (2-butyl-1,3-hexanediolato) titanium, tetrakis (1,3-hexanediolato) titanium, tetrakis (1,3-pentanediolato) titanium, tetrakis (2-methyl-1) , 3-pentanediolato) titanium, tetrakis (2-ethyl-1,3-pentanediolato) titanium, tetrakis (2-propyl-1,3-pentanediolato) titanium, tetrakis (2-butyl-1,3) -Pentanediolato) titanium, tetrakis (1,3-heptanediolato) titanium, tetrakis (2-methyl-1,3-heptanediolato) Titanium, tetrakis (2-ethyl-1,3-heptanediolato) titanium, tetrakis (2-propyl-1,3-heptanediolato) titanium, tetrakis (2-butyl-1,3-heptanediolato) titanium, tetrakis (2-ethylhexoxy) Titanium, tetramethoxy titanium, tetraethoxy titanium, tetra-n-propoxy titanium, tetraisopropoxy titanium, tetra-n-butoxy titanium, tetra-n-butoxy titanium oligomer, tetraisobutoxy titanium, tetra-sec-butoxy titanium, tetra Tert-butoxy titanium, bis (oleate) bis (2-ethylhexanoate) titanium, titanium dipropoxy bis (triethanolamate), titanium dibutoxy bis (triethanolaminate), titanium tributoxy Tearate, titanium tripropoxy systemate, titanium tripropoxyacetylacetonate, titanium dipropoxybis (acetylacetonate), titanium tripropoxy (ethylacetoacetate), titanium propoxyacetylacetonatebis (ethylacetoacetate), titanium tributoxyacetyl Acetonate, Titanium dibutoxybis (acetylacetonate), Titanium tributoxyethyl acetoacetate, Titanium butoxyacetylacetonate bis (ethylacetoacetate), Titanium tetrakis (acetylacetonate), Titanium diacetylacetonate bis (ethylacetoacetate) Bis (2-ethylhexanoate) titanium oxide, bis (laurate) titanium oxide, bis (naphthenate) titanium oxide Id, bis (stearate) titanium oxide, bis (oleate) titanium oxide, bis (linoleate) titanium oxide, tetrakis (2-ethylhexanoate) titanium, tetrakis (laurate) titanium, tetrakis (naphthenate) titanium, tetrakis (stear) Rate) titanium, tetrakis (oleate) titanium, tetrakis (linoleate) titanium, titanium di-n-butoxide (bis-2,4-pentanedionate), titanium oxide bis (stearate), titanium oxide bis (tetramethylheptanedionate) ), Titanium oxide bis (pentanedionate), titanium tetra (lactate) and the like.
Of these, tetrakis (2-ethyl-1,3-hexanediolato) titanium, tetrakis (2-ethylhexoxy) titanium, and titanium di-n-butoxide (bis-2,4-pentanedionate) are preferable.

As a condensation accelerator containing Sn as a metal component, an oxidation number 2 tin compound represented by Sn (OCOR ³¹ ) ₂ (wherein R ³¹ is an alkyl group having 2 to 19 carbon atoms), R ³² _x SnA ⁵ _y B ¹ _4- yx tin compound having an oxidation number of 4 (wherein R ³² is an aliphatic hydrocarbon group having 1 to 30 carbon atoms, x is an integer of 1 to 3, y is 1) Or 2, A ⁵ is a carboxyl group having 2 to 30 carbon atoms, a β-dicarbonyl group having 5 to 20 carbon atoms, a hydrocarbyloxy group having 3 to 20 carbon atoms, and a hydrocarbyl group and / or carbon having 1 to 20 carbon atoms. A group selected from siloxy groups tri-substituted with a hydrocarbyloxy group of 1 to 20 and B ¹ is a hydroxyl group or a halogen group).

More specifically, the tin carboxylate includes divalent tin dicarboxylate, tetravalent dihydrocarbyltin dicarboxylate (including bis (hydrocarbyldicarboxylic acid) salt), bis (β -Diketonates), alkoxy halides, monocarboxylate hydroxides, alkoxy (trihydrocarbylsiloxides), alkoxy (dihydrocarbylalkoxysiloxides), bis (trihydrocarbylsiloxides), bis (dihydrocarbylalkoxysiloxides), etc. It can be used suitably. The hydrocarbyl group bonded to tin preferably has 4 or more carbon atoms, and particularly preferably has 4 to 8 carbon atoms.

In addition, examples of the condensation accelerator (for example, alkoxide, carboxylic acid, or acetylacetonate complex salt of these metals) containing Zr, Bi, or Al as a metal component include the following (a) to (e).

(A) Bismuth carboxylate (b) Zirconium alkoxide (c) Zirconium carboxylate (d) Aluminum alkoxide (e) Aluminum carboxylate

Specifically, tris (2-ethylhexanoate) bismuth, tris (laurate) bismuth, tris (naphthenate) bismuth, tris (stearate) bismuth, tris (oleate) bismuth, tris (linoleate) bismuth, tetraethoxyzirconium , Tetra-n-propoxyzirconium, tetraisopropoxyzirconium, tetra-n-butoxyzirconium, tetrasec-butoxyzirconium, tetratert-butoxyzirconium, tetra (2-ethylhexoxy) zirconium, zirconium tributoxyzirate, zirconium tributoxyacetylacetonate , Zirconium butoxybis (acetylacetonate), zirconium tributoxyethyl acetoacetate, zirconium butoxyacetyl Acetonate bis (ethyl acetoacetate), zirconium tetrakis (acetylacetonate), zirconium diacetylacetonate bis (ethylacetoacetate), bis (2-ethylhexanoate) zirconium oxide, bis (laurate) zirconium oxide, bis (naphthenate) ) Zirconium oxide, bis (stearate) zirconium oxide, bis (oleate) zirconium oxide, bis (linoleate) zirconium oxide, tetrakis (2-ethylhexanoate) zirconium, tetrakis (laurate) zirconium, tetrakis (naphthenate) zirconium, tetrakis (Stearate) zirconium, tetrakis (oleate) zirconium, tetrakis (linoleate) zir Ni, triethoxyaluminum, tri-n-propoxyaluminum, triisopropoxyaluminum, tri-n-butoxyaluminum, trisec-butoxyaluminum, tritert-butoxyaluminum, tri (2-ethylhexoxy) aluminum, aluminum dibutoxy systemate, aluminum Dibutoxyacetylacetonate, aluminum butoxybis (acetylacetonate), aluminum dibutoxyethylacetoacetate, aluminum tris (acetylacetonate), aluminum tris (ethylacetoacetate), tris (2-ethylhexanoate) aluminum, tris (Laurate) aluminum, tris (naphthenate) aluminum, tris (stearate) aluminum, tris (Oleate) aluminum, tris (linoleate) aluminum, etc. are mentioned.

Among these, tris (2-ethylhexanoate) bismuth, tetra n-propoxyzirconium, tetra n-butoxyzirconium, bis (2-ethylhexanoate) zirconium oxide, bis (oleate) zirconium oxide, triisopropoxy Aluminum, trisec-butoxyaluminum, tris (2-ethylhexanoate) aluminum, tris (stearate) aluminum, zirconium tetrakis (acetylacetonate), and aluminum tris (acetylacetonate) are preferred.

The blending amount (use amount) of the condensation accelerator is preferably such that it is 0.1 to 10 parts by weight, based on 100 parts by weight of the rubber component in the rubber composition described later, and 0.5 to 5 parts by weight. Part is more preferred. By setting the use amount of the condensation accelerator within the above range, the condensation reaction proceeds efficiently.

The condensation reaction is preferably carried out in an aqueous solution, and the temperature during the condensation reaction is preferably 85 to 180 ° C., more preferably 100 to 170 ° C., and particularly preferably 110 to 150 ° C. By setting the temperature during the condensation reaction within the above range, the condensation reaction can be progressed and completed efficiently, and the deterioration of the quality due to the aging reaction of the polymer due to changes over time of the resulting modified conjugated diene polymer is suppressed. Can do.

The condensation reaction time is preferably about 5 minutes to 10 hours, more preferably about 15 minutes to 5 hours. By setting the condensation reaction time within the above range, the condensation reaction can be completed smoothly.
The pressure of the reaction system during the condensation reaction is preferably 0.01 to 20 MPa, more preferably 0.05 to 10 MPa.
There is no restriction | limiting in particular about the form of a condensation reaction, You may carry out by a continuous type using apparatuses, such as a batch type reactor and a multistage continuous reactor. Moreover, you may perform this condensation reaction and desolvent simultaneously.

After completion of the hydrolysis step or hydrolysis step and condensation reaction step described above, 2,6-di-t-butyl-p-cresol (BHT) isopropanol solution or the like is added to the polymerization reaction system to stop the polymerization reaction. To do.
Thereafter, the modified conjugated diene (co) polymer of the present invention is obtained through a desolvation treatment such as steam stripping for reducing the partial pressure of the solvent by blowing water vapor or a vacuum drying treatment.
Here, in the modification reaction step, when the hydrocarbyloxysilane compound having a protected primary amino group is used as the organic silane compound represented by the general formula (2), the above-described hydrolysis step, steam stripping, etc. In the desolvation treatment step using water vapor, deprotection treatment is performed simultaneously to remove the protecting group of the protected nitrogen atom to generate a primary amino group. In any stage until it becomes a dry polymer, it is converted to the free primary amino group by hydrolyzing the protecting group on the primary amino group by various methods as necessary, and derived from the hydrocarbyloxysilane compound The deprotection treatment of the protected primary amino group can be performed.

Next, a modified conjugated diene (co) polymer (hereinafter referred to as a modified conjugated diene (co) polymer I) obtained by the above-described production method will be described.
[Modified Conjugated Diene (Co) polymer I]
The modified conjugated diene (co) polymer I in the present invention is a molecule comprising a silanol group and a functional group in the vicinity of the silanol group, which promotes the reaction between the silanol group and the reinforcing filler. At the chain end.
The modified conjugated diene (co) polymer I in the present invention is more specifically a modified conjugated diene (co) polymer represented by the following general formula (3) or the following general formula (4).

Here, R ¹ is a single bond or a divalent hydrocarbon group having 1 to 20 carbon atoms; R ² and R ³ are each independently hydrogen or a monovalent hydrocarbon group having 1 to 20 carbon atoms; A ³ is a silanol A functional group that promotes the reaction between the group and the reinforcing filler, and m is an integer of 1 to 10.

Here, R ⁴ is a single bond or a hydrocarbon group having 1 to 20 carbon atoms; R ⁵ and R ⁶ are each independently a single bond, hydrogen or a hydrocarbon group having 1 to 20 carbon atoms; A ⁴ is a single bond, carbon Functional groups that promote the reaction between the hydrocarbon group or silanol group of formula 1 to 20 and the reinforcing filler; and B and D are each independently at least one functional group that promotes the reaction between the silanol group and the reinforcing filler. P and q each independently represents an integer of 0 to 5, and (p + q) is 1 or more. n is an integer of 1 to 10, preferably an integer of 1 to 6.
Note that (Polymer)-is a polymer chain of a modified conjugated diene (co) polymer.

In the general formula (3) and the general formula (4), R ¹ , R ⁴ , R ⁵ when p is 1 or R ⁶ when q is 1 is a divalent having 1 to 20 carbon atoms Specific examples of the hydrocarbon group of R ⁵ in the case where R ¹ , R ⁴ and p in the general formula (1) and the general formula (2) are 1 or R ⁶ in the case where q is 1 and The same specific example is given.
In the general formula (3) and the general formula (4), R ² , R ³ , p ⁵ is 0, or R ^{5 is} q 0 and R ⁶ is C 1-20 Specific examples of the monovalent hydrocarbon group include R ⁵ when R ² , R ³ , and p in the general formula (1) and the general formula (2) are 0 or R when q is 0. Specific examples thereof are the same as the monovalent hydrocarbon group having ⁶ to 20 carbon atoms which is ⁶ .

In the general formula (3) and the general formula (4), as the functional groups A ³ and A ⁴ that promote the reaction between the silanol group and the reinforcing filler, each independently, for example, a (thio) ether bond, A divalent functional group having at least one bond selected from (thio) urethane bond, imino bond and amide bond, and nitrile group (cyano group), pyridyl group, N-alkylpyrrolidonyl group, N-alkyl Imidazolyl group, N-alkylpyrazolyl group, (thio) ketone group, (thio) aldehyde group, isocyanuric acid triester residue, (thio) carboxylic acid hydrocarbyl ester residue having 1 to 20 carbon atoms, 1 to 20 carbon atoms (Thio) carboxylic acid metal salt residue, carboxylic acid anhydride residue having 1 to 20 carbon atoms, carboxylic acid halide residue having 1 to 20 carbon atoms, and dicarbonate Is at least one divalent functional group selected from the group consisting of divalent functional group derived from a functional group selected from the mud hydrocarbyl ester residue.
Here, the divalent functional group having at least one bond selected from (thio) ether bond, (thio) urethane bond, imino bond and amide bond is (thio) ether bond, (thio) urethane bond, It may be an imino bond or an amide bond, or a divalent hydrocarbon group having 1 to 20 carbon atoms having a (thio) ether bond, a (thio) urethane bond, an imino bond and / or an amide bond. . Examples of the divalent hydrocarbon group having 1 to 20 carbon atoms include R ⁵ or q in the case where R ¹ , R ⁴ , and p in the general formula (1) and the general formula (2) are 1, Specific examples are the same as R ^{6 in a} certain case.

The general formula (3), and ^{A 3} and ^{A 4} in the general formula (4), each of ^{A 2} of ^{A 1} and of the general formula (1) (2), the modified conjugated diene (co) polymer activity It shows a functional group bonded to the site and has an action of promoting the reaction between the silanol group formed in the hydrolysis reaction step and the reinforcing filler.

In the general formula (4), the groups B and D containing at least one functional group that promotes the reaction between the silanol group and the reinforcing filler are each independently a primary amino group, a secondary amino group, and a protected group. Primary or secondary amino group, tertiary amino group, cyclic amino group, oxazolyl group, imidazolyl group, aziridinyl group, (thio) ketone group, (thio) aldehyde group and amide group, (thio) epoxy group, glycidoxy group (Thio) isocyanate group, nitrile group (cyano group), pyridyl group, N-alkylpyrrolidonyl group, N-alkylimidazolyl group, N-alkylpyrazolyl group, imino group, amide group, ketimine group, imine residue, Isocyanuric acid triester residue, (thio) carboxylic acid hydrocarbyl ester residue having 1 to 20 carbon atoms, (thio) carbon having 1 to 20 carbon atoms Residues of boronic acid metal salts, carboxylic acid anhydride residues having 1 to 20 carbon atoms, carboxylic acid halide residues having 1 to 20 carbon atoms, carbonic acid dihydrocarbyl ester residues and the general formula -EFG Examples include at least one functional group selected from the functional groups represented.
Here, E is an imino group, a divalent imine residue, a divalent pyridine residue or a divalent amide residue, F is an alkylene group having 1 to 20 carbon atoms, a phenylene group or an aralkylene having 8 to 20 carbon atoms Group G is primary amino group, secondary amino group, protected primary or secondary amino group, tertiary amino group, cyclic amino group, oxazolyl group, imidazolyl group, aziridinyl group, ketimine group, nitrile group (cyano Group), an amide group, a pyridine group or a (thio) isocyanate group.
Specific examples of the functional group represented by the general formula -EFFG are as described above.
The protected functional group capable of leaving the primary or secondary amino group may remain in the modified conjugated diene (co) polymer of the present invention without being deprotected.

As shown in the general formula (3) or the general formula (4), the modified conjugated diene (co) polymer of the present invention preferably has only one silanol group in the molecular chain. This is because when two or more silanol groups are present in the molecular chain, the silanol groups are condensed with each other, and the viscosity of the modified conjugated diene (co) polymer is increased, which may make the kneading operation difficult.

In this embodiment, the modified conjugated diene (co) polymer has both a silanol group and a functional group that promotes the reaction between the silanol group and the reinforcing filler in the vicinity of the silanol group. Only modified conjugated diene (co) polymers that do not have functional groups that promote the reaction between silanol groups and reinforcing filler, and functional groups that promote the reaction between silanol groups and reinforcing filler. As compared with the modified conjugated diene (co) polymer having no silanol group, both the silica-containing rubber composition and the carbon black-containing rubber composition improve the low heat build-up.

In the present embodiment, the modified conjugated diene (co) polymer does not limit the vinyl bond content of the conjugated diene part, but is preferably 70% or less. If it is 70% or less, the fracture characteristics and the wear characteristics are improved when used for a tire tread. The styrene content is preferably 0 to 50% by mass. This is because if it is 50% by mass or less, the balance between low heat build-up and wet skid performance is improved.
The vinyl bond content is determined by calculating the integral ratio of the spectrum by infrared method (Morero method) and the styrene content by ¹ H-NMR.

[Rubber component B]
The rubber component B applicable to the rubber composition according to this embodiment has a glass transition temperature of −35 ° C. or higher. The glass transition point of the rubber component B is preferably higher than the glass transition point of the rubber component A.
When the glass transition temperature of the rubber component B is less than −35 ° C., sufficient wet grip performance cannot be obtained. In this respect, the glass transition temperature of the rubber component B is more preferably −30 ° C. or higher, and further preferably −25 ° C. or higher.
Further, the styrene content + 1/2 vinyl content of the rubber component B is preferably 45% by mass or more, and more preferably 50% by mass or more. If the rubber component B has the above properties, sufficient wet grip performance can be obtained.
Examples of the diene rubber that can be used as the rubber component B include natural rubber, polybutadiene rubber, synthetic polyisoprene rubber, styrene-isoprene rubber, ethylene-butadiene copolymer rubber, propylene-butadiene copolymer rubber, ethylene-propylene- Examples thereof include butadiene copolymer rubber, ethylene-α-olefin-diene copolymer rubber, butyl rubber, halogenated butyl rubber, a copolymer of styrene having a halogenated methyl group and isobutylene, and chloroprene rubber.

[Reinforcing filler]
The rubber composition according to this embodiment preferably contains 30 to 150 parts by mass of reinforcing filler, and 40 to 120 parts by mass with respect to 100 parts by mass in total of rubber component A and rubber component B. It is more preferable to contain. If it is 30 parts by mass or more, the wear resistance is improved, and if it is 150 parts by mass or less, the fuel efficiency is improved.
The reinforcing filler is preferably silica and / or carbon black. In particular, the filler is preferably silica alone or silica and carbon black, and the content ratio of silica to carbon black (silica: carbon black) is (100: 0) to (30:70) in mass ratio. Is more preferable, and (100: 0) to (50:50) is more preferable. The compounding amount of silica is preferably 10 to 100 parts by mass, and more preferably 30 to 80 parts by mass with respect to 100 parts by mass of the rubber component. If it is this range, low-fuel-consumption property and abrasion resistance can be improved further.

Examples of silica include wet silica (hydrous silicic acid), dry silica (anhydrous silicic acid), calcium silicate, aluminum silicate, and the like. Among them, wet is most effective in achieving both wet performance and wear resistance. Silica is preferred.
The BET specific surface area (measured in accordance with ISO 5794/1) of silica is preferably 80 m ² / g or more, more preferably 120 m ² / g or more, and particularly preferably 150 m ² / g or more. Although there is no restriction | limiting in particular in the upper limit of a BET specific surface area, Usually, it is about 450 m < ² > / g. Examples of such silica include Tosoh Silica Co., Ltd., trade name “Nip Seal AQ” (BET specific surface area = 205 m ² / g), “Nip Seal KQ”, manufactured by Degussa, trade name “Ultra Gil VN 3” (BET specific surface area). = 175 m ² / g) and the like can be used.

There is no restriction | limiting in particular as carbon black, For example, HAF, N339, IISAF, 1 SAF, SAF etc. are used. The specific surface area (measured in accordance with N ₂ SA, JIS K 6217-2: 2001) of the nitrogen adsorption method of carbon black is preferably 70 to 180 m ² / g, more preferably 80 to 180 m ² / g. Further, DBP oil absorption amount (JIS K 6217-4: measured according to 2008) is preferably 70 ^~ 160cm 3 / 100g, more preferably 90 ^~ 160cm 3 / 100g. By using carbon black, improvement effects such as fracture resistance and wear resistance are increased. N339, IISAF, ISAF, and SAF, which are excellent in wear resistance, are particularly preferable.
One type of silica and / or carbon black may be used, or two or more types may be used in combination.

[Silane coupling agent]
In the rubber composition according to the present embodiment, if desired, when silica is used as one of the reinforcing fillers, a silane coupling agent is used for the purpose of further improving the reinforcing property and fuel efficiency of the rubber composition. It is preferable to mix.
Examples of silane coupling agents include bis (3-triethoxysilylpropyl) tetrasulfide, bis (3-triethoxysilylpropyl) trisulfide, bis (3-triethoxysilylpropyl) disulfide, and bis (2-triethoxysilyl). Ethyl) tetrasulfide, bis (3-trimethoxysilylpropyl) tetrasulfide, bis (2-trimethoxysilylethyl) tetrasulfide, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 2-mercaptoethyltri Methoxysilane, 2-mercaptoethyltriethoxysilane, 3-trimethoxysilylpropyl-N, N-dimethylthiocarbamoyl tetrasulfide, 3-triethoxysilylpropyl-N, N-dimethylthiocarba Yl tetrasulfide, 2-triethoxysilylethyl-N, N-dimethylthiocarbamoyl tetrasulfide, 3-trimethoxysilylpropylbenzothiazolyl tetrasulfide, 3-triethoxysilylpropylbenzoyltetrasulfide, 3-triethoxysilyl Propyl methacrylate monosulfide, 3-trimethoxysilylpropyl methacrylate monosulfide, bis (3-diethoxymethylsilylpropyl) tetrasulfide, 3-mercaptopropyldimethoxymethylsilane, dimethoxymethylsilylpropyl-N, N-dimethylthiocarbamoyl tetrasulfide , Dimethoxymethylsilylpropylbenzothiazolyl tetrasulfide, 3-octanoylthiopropyltriethoxysilane, and the like. From the viewpoint of reinforcing effect of improving al, bis (3-triethoxysilylpropyl) polysulfide, 3-octanoylthiopropyl propyltriethoxysilane and 3-trimethoxysilylpropyl benzothiazyl tetrasulfide are preferable.
One of these silane coupling agents may be used alone, or two or more thereof may be used in combination.

From the viewpoint of the effect as a coupling agent and prevention of gelation, the preferable blending amount of this silane coupling agent is such that the mass ratio (silane coupling agent / silica) is (1/100) to (20/100). It is preferable. If it is (1/100) or more, the effect of improving the low heat build-up of the rubber composition will be more suitably exhibited. If it is (20/100) or less, the cost of the rubber composition will be reduced, and the economic efficiency will be reduced. This is because it improves. Further, a mass ratio (3/100) to (20/100) is more preferable, and a mass ratio (4/100) to (10/100) is particularly preferable.

[Other additives]
In the rubber composition according to the present embodiment, various chemicals usually used in the rubber industry, for example, a vulcanizing agent, a vulcanization accelerator, a process oil, and an aging as long as the effects of the present invention are not impaired. An inhibitor, a scorch inhibitor, zinc white, stearic acid and the like can be contained.
Examples of the vulcanizing agent include sulfur. The amount of the vulcanizing agent used is preferably 0.1 to 10.0 parts by weight, more preferably 1.0 to 5.0 parts by weight, based on 100 parts by weight of the rubber component. If the amount is less than 0.1 parts by mass, the fracture strength, wear resistance, and fuel efficiency of the vulcanized rubber may be reduced. If the amount exceeds 10.0 parts by mass, the rubber elasticity is lost.

Examples of the vulcanization accelerator that can be used in the rubber composition according to this embodiment include M (2-mercaptobenzothiazole), DM (dibenzothiazyl disulfide), and CZ (N-cyclohexyl-2-benzothiazylsulfenamide). ), Thiazole series, guanidine series such as DPG (diphenylguanidine), or thiuram series vulcanization accelerators such as TOT (tetrakis (2-ethylhexyl) thiuram disulfide). The amount is preferably 0.1 to 5.0 parts by weight, more preferably 0.2 to 3.0 parts by weight, based on 100 parts by weight of the rubber component.

Also, as the process oil used as a softening agent that can be used in the rubber composition according to the present embodiment, an aromatic oil is used from the viewpoint of compatibility with SBR. In addition, naphthenic oil or paraffinic oil is used from the viewpoint of emphasizing low temperature characteristics. The amount used is preferably 0 to 100 parts by mass with respect to 100 parts by mass of the rubber component, and if it is 100 parts by mass or less, the deterioration of the tensile strength and low fuel consumption (low heat generation) of the vulcanized rubber is suppressed. can do.

Examples of the anti-aging agent that can be used in the rubber composition according to this embodiment include 3C (N-isopropyl-N′-phenyl-p-phenylenediamine, 6C [N- (1,3-dimethylbutyl) -N′- Phenyl-p-phenylenediamine], AW (6-ethoxy-2,2,4-trimethyl-1,2-dihydroquinoline), high-temperature condensate of diphenylamine and acetone, etc. The amount used is rubber. The amount is preferably from 0.1 to 5.0 parts by weight, more preferably from 0.3 to 3.0 parts by weight, based on 100 parts by weight of the component.

[Preparation of rubber composition, production of pneumatic tire]
The rubber composition according to this embodiment can be obtained by kneading the above-described various components and additives using a kneader such as a Banbury mixer, a roll, or an internal mixer.
That is, in the rubber composition according to the present embodiment, the rubber component A, the rubber component B, and the reinforcing filler are kneaded in the first stage of kneading, and then the vulcanizing agent and vulcanization acceleration are performed in the final stage of kneading. It can produce by mixing an agent.
Since the rubber component A contains a modified conjugated diene (co) polymer having a high affinity with a reinforcing filler such as silica, the rubber component A and the rubber component B out of the rubber component A and the rubber component B are mixed. The reinforcing filler can be well dispersed in component A.
The obtained rubber composition is further molded and then vulcanized to produce a tread of a pneumatic tire, particularly a tread grounding portion.
Moreover, a tire is manufactured by a normal tire manufacturing method using the rubber composition according to the present embodiment for a tread. That is, the rubber composition containing the above-mentioned various chemicals is processed into each member at an unvulcanized stage, and is pasted and molded by a normal method on a tire molding machine to form a raw tire. The green tire is heated and pressed in a vulcanizer to obtain a tire. In this way, a tire having low heat build-up and good wear resistance, particularly a pneumatic tire can be obtained.

Hereinafter, the present invention will be described in detail with reference to examples. The present invention is not limited to the examples.
[Measuring method]
Each characteristic was evaluated according to the following method.
<Tire performance>
A vulcanized rubber sample was cut out from the tire tread and evaluated as follows.
(Wet grip performance)
Using a viscoelastic spectrometer (manufactured by Toyo Seiki Co., Ltd.), tan δ was measured at a frequency of 52 Hz, an initial strain of 10%, a measurement temperature of 0 ° C., and a dynamic strain of 1%. Expressed as an index. The larger the index value, the better the wet grip performance.
Wet performance index = {(tan δ value of test tire) / (tan δ value of Comparative Example 1)} × 100

(Low heat generation)
Using a viscoelastic spectrometer (manufactured by Toyo Seiki Co., Ltd.), tan δ was measured at a frequency of 52 Hz, an initial strain of 10%, a measurement temperature of 60 ° C., and a dynamic strain of 1%, and the reciprocal of the tan δ value of Comparative Example 1 was taken as 100. Expressed as an index according to the formula. The larger the index value, the better the low heat buildup.
Low exothermic index = {(tan δ value of Comparative Example 1) / (tan δ value of test tire)} × 100

(Abrasion resistance)
A vulcanized rubber sample was cut out from the tire tread, and the amount of wear with a slip rate of 60% at room temperature was measured according to JIS K6264 using a Lambone-type wear tester. Expressed as an index according to the formula. The greater the value of this index, the better the wear resistance.
Wear resistance index = {(Abrasion amount of Comparative Example 1) / (Abrasion amount of test tire)} × 100

[Production example]
Production Example 1: Production of Modified SBR1 Modified SBR1 described later was produced as follows. That is, 2750 g of cyclohexane, 29.5 g of tetrahydrofuran, 50 g of styrene, and 450 g of 1,3-butadiene were charged into an autoclave reactor having an internal volume of 5 liters purged with nitrogen. After adjusting the temperature of the reactor contents to 10 ° C., 215 mg of n-butyllithium was added to initiate polymerization. The polymerization was carried out under adiabatic conditions and the maximum temperature reached 85 ° C.
When the polymerization conversion rate reached 99%, 10 g of butadiene was added, and polymerization was further performed for 5 minutes. From the reactor, a small amount of the polymer solution was sampled in 30 g of a cyclohexane solution to which 1 g of methanol was added, and then 1129 mg of aminopropylmethyldiethoxysilane was added and the modification reaction was carried out for 15 minutes to obtain a modified SBR1.
The obtained modified SBR1 had a styrene content of 10%, a vinyl content of the diene compound portion of 40%, and a Tg of about -70 ° C.

Production Example 2: Production of Modified SBR2 A 5-liter autoclave reactor that had been dried and purged with nitrogen was charged with 2500 g of cyclohexane, 25 g of tetrahydrofuran, 100 g of styrene, and 390 g of 1,3-butadiene. After adjusting the temperature of the reactor contents to 10 ° C., 375 mg of n-butyllithium (BuLi) was added to initiate polymerization. The polymerization was carried out under adiabatic conditions and the maximum temperature reached 85 ° C. When the polymerization conversion rate reaches 99%, 10 g of butadiene is added and further polymerized for 5 minutes, and then 100 mg of silicon tetrachloride is added and reacted for 5 minutes, followed by N, N-bis (trimethylsilyl) amino. 1020 mg of propylmethyldiethoxysilane was added and the reaction was performed for 15 minutes. 2,6-di-t-butyl-p-cresol (BHT) was added to the polymer solution after the reaction to stop the reaction. Subsequently, the solvent was removed by steam stripping, and drying was performed with a hot roll adjusted to 110 ° C. to obtain modified SBR2.
The obtained modified SBR2 had a styrene content of 25%, a vinyl content of the diene compound portion of 55%, and a Tg of about −15 ° C.

Production Example 3: Production of modified BR A glass bottle with a rubber cap of about 1 liter was dried and purged with nitrogen, and a cyclohexane solution of butadiene that had been purified by drying and dry cyclohexane were added thereto, respectively. A state where 330 g of a cyclohexane solution was charged was used. To this was added 0.513 mmol of hexamethyleneimine (HMI). Next, 0.36 mL of tert-butyllithium (1.57M) and 0.057 mL of 2,2-di (2-tetrahydrofuryl) propane (0.2N) were added and the mixture was 4.5 hours in a 50 ° C. water bath. Polymerization was performed. Thereafter, 0.10 mmol of tin tetrachloride (SnCl ₄ ) was added at 50 ° C. and reacted for 1 hour. After reprecipitation in isopropanol containing a small amount of NS-5, it was dried on a drum to obtain modified BR in a yield of almost 100%.

[Examples and Comparative Examples]
Table 1 shows the properties of the rubber components used in the production of the rubber composition of the specimen. Rubber compositions having the composition shown in Table 2 were prepared, and pneumatic rubber tires (tire size 195 / 60R15) for passenger cars were manufactured according to conventional methods using these rubber compositions in the tread portion. The performance of each of the obtained specimen tires was evaluated by the method described above.

[note]
* 1 NR: Natural rubber * 2 SBR1: JSR Corporation emulsion emulsion polymerization SBR "E-SBR" (styrene content 40%, diene compound vinyl content 19%, glass transition temperature -31 ° C)
* 3 SBR2: ESR SBR "E-SBR" manufactured by JSR Corporation (45% styrene, 19% vinyl in diene compound, glass transition temperature -24 ° C)
* 4 SBR3: ESR SBR “E-SBR” manufactured by JSR Corporation (styrene content 37%, diene compound vinyl content 19%, glass transition temperature −38 ° C.)
* 5 SBR4: ESR SBR "E-SBR" manufactured by JSR Corporation (styrene content 24%, diene compound vinyl content 19%, glass transition temperature -55 ° C)
* 6 SBR5: Solution polymerization SBR “S-SBR” manufactured by JSR Corporation (styrene content 39%, vinyl content of diene compound part 40%, glass transition temperature −15 ° C.)
* 7 Modified SBR1: The one obtained in Production Example 1 was used.
* 8 Unmodified BR: “Diene NF35R” manufactured by Asahi Kasei Corporation
* 9 Modified SBR2: The one obtained in Production Example 2 was used.
* 10 Modified BR: The one obtained in Production Example 3 was used.
* 11 Made by Tosoh Silica Co., Ltd., trade name “Nip Seal AQ” (BET specific surface area = 205 m ² / g)
* 12 Carbon black: “Asahi # 70 (N330)” manufactured by Asahi Carbon Co., Ltd.
* 13 Silane coupling agent: bis (3-triethoxysilylpropyl) disulfide (average sulfur chain length: 2.35), manufactured by Evonik, trade name “Si75”
* 14 Process oil: Aromatic oil, “Aromax # 3” manufactured by Fuji Kosan Co., Ltd.
* 15 Anti-aging agent 6C: N- (1,3-dimethyl) -N′-phenyl-p-phenylenediamine, manufactured by Ouchi Shinsei Chemical Co., Ltd. “NOCRACK 6C”
* 16 Vulcanization accelerator DM: Dibenzothiazyl sulfide, manufactured by Ouchi Shinsei Chemical Co., Ltd., “Noxeller DM-P”

[Evaluation results]
According to the results shown in Tables 1 and 2, by using a rubber component having a glass transition point of −35 ° C. or higher and a rubber component lower than this, and using those incompatible with each other , Wet grip performance is improved. Moreover, the dispersibility of the silica which is a reinforcing filler can be improved by using modified SBR having a relatively low glass transition point. Thereby, the low heat generation property is improved.

Claims

A rubber component A containing natural rubber and a modified conjugated diene (co) polymer having a glass transition temperature of −50 ° C. or lower, a rubber component B having a glass transition temperature of −35 ° C. or higher, and a reinforcing filler are blended. Become
The modified conjugated diene (co) polymer has a silanol group at a molecular end of the conjugated diene (co) polymer and a functional group in the vicinity of the silanol group, the silanol group and the reinforcing filler. And a functional group that promotes the reaction,
2. A rubber composition, wherein two peaks based on each of the rubber component A and the rubber component B are observed in a temperature dispersion curve of tan δ by a dynamic viscoelasticity test.
The rubber composition according to claim 1, wherein the rubber component A is contained in an amount of 50% by mass or more based on the total mass of the rubber component A and the rubber component B.
The rubber composition according to claim 1 or 2, wherein a ratio of the natural rubber in the rubber component A is 10% by mass or more and 80% by mass or less based on a total mass of the rubber component A.
A tire using the rubber composition according to any one of claims 1 to 3.