JP5463042B2 - Rubber composition and tire using the same - Google Patents

Description

  The present invention relates to a rubber composition and a tire using the rubber composition. More specifically, the present invention relates to a rubber composition capable of reducing a hysteresis loss and providing a tire with good rolling resistance, and a tire using the rubber composition.

In recent years, there has been an increasing demand for fuel efficiency reduction of automobiles in connection with the global movement of regulation of carbon dioxide emissions due to increasing interest in environmental problems. In order to meet such demands, reduction of rolling resistance is also demanded for tire performance. Conventionally, as a technique for reducing the rolling resistance of a tire, a technique for optimizing the tire structure has been studied, but it is currently the most important to use a rubber composition having a lower hysteresis loss as a rubber composition applied to the tire. This is done as a general method.
As a method of obtaining such a rubber composition having a low hysteresis loss, a method of using silica as a filler to be used is known.
However, silica has a problem that the storage elastic modulus does not increase because the dispersibility of the filler is poor and vulcanization is delayed as compared with carbon black.

  In order to improve the above-mentioned drawbacks, Patent Document 1 discloses (A) natural rubber and / or diene synthetic rubber, (B) inorganic filler, and (C) reactive group A for rubber (A) in the same molecule. A compound having at least one and two or more adsorption groups B for the inorganic filler (B), (D) selected from maleic acid, fumaric acid, itaconic acid and sorbic acid as the reactive group A for the rubber (A) in the same molecule A rubber containing at least one compound selected from an acrylate ester or a methacrylate ester having a specific structure, or (E) a compound having one or more groups A and amino groups each derived from an unsaturated carboxylic acid Compositions have been proposed. This improves the dispersibility of the inorganic filler and increases the storage elastic modulus of the vulcanized rubber composition without increasing the viscosity of the unvulcanized rubber and without impairing the processability, but reduces the rolling resistance. It was difficult to do.

  Patent Document 2 or 3 proposes a rubber composition using a modified conjugated diene polymer in which an amino group is introduced at a polymerization active terminal as a rubber component and carbon black as a filler in order to reduce rolling resistance. In Patent Document 4 or 5, it is also proposed to blend silica with these modified conjugated diene polymers.

JP 2003-176378 A JP-A-8-225604 JP-A-8-231658 JP-A-2005-232351 JP 2006-241358 A

Although the above-mentioned technology has made it possible to realize a rubber composition having a low hysteresis loss that gives a tire having a good rolling resistance as compared with the previous technology, further improvement is desired as the technology advances today.
The present invention has been made under such circumstances, and an object thereof is to provide a rubber composition capable of further reducing hysteresis loss and giving a tire having good rolling resistance, and a tire using the rubber composition. It is what.

As a result of intensive studies to achieve the above object, the present inventor used a condensation accelerator after reacting an alkoxysilane compound with the active end of a conjugated diene polymer having an alkali metal active end. A rubber composition containing a rubber component containing a modified conjugated diene polymer obtained by conducting a condensation reaction at a certain value or more, an inorganic filler containing silica, and a specific silane coupling agent in a predetermined ratio. It was found that the object can be achieved by the product.
The present invention has been completed based on such findings.

That is, the present invention
[1] (A) A rubber component containing 10% by mass or more of a modified conjugated diene polymer and 100 parts by mass of (B) 10 to 140 parts by mass of an inorganic filler containing silicic acid; (C) A rubber composition containing a silane coupling agent in a proportion of 1 to 20% by mass relative to the inorganic filler (B),
(1) The modified conjugated diene polymer is an alkoxysilane compound at the active terminal of the conjugated diene polymer having an alkali metal active terminal obtained by anionic polymerization using (a) an alkali metal initiator. And (b) a step of performing a condensation reaction in the presence of a condensation accelerator composed of a compound of an element belonging to at least one of Groups 4, 13, 14, and 15 of the periodic table. And (2) the (C) silane coupling agent is represented by the following general formula (1):
And / or a compound represented by the following general formula (2) and / or a compound represented by the following general formula (3) and a diol compound represented by the following general formula (4): A rubber composition characterized in that it is a compound obtained.
A _a B _b D _c Si—X—S—CO—X ¹ (1)
[In the formula, A represents an alkoxy group having 1 to 3 carbon atoms or a chlorine atom, B represents an alkyl group having 1 to 3 carbon atoms, X represents an alkanediyl group or alkenediyl group having 1 to 9 carbon atoms, or 6 to 15 carbon atoms. arylene group, X ¹ is an aryl group or an aralkyl group of saturated or unsaturated alkyl group, or a 6 to 15 carbon atoms having 1 to 20 carbon atoms. D is A, B, or — [O (XO) _n ] _0.5 — group, n is an integer of 1 to 4, and may have a distribution. a, b, and c are numbers satisfying the relationship of 0 ≦ a ≦ 3, 0 ≦ b ≦ 2, 0 ≦ c ≦ 1.5, and a + b + 2c = 3. ]
A _e B _f Si—XS—CO—X ¹ (2)
A _e B _f Si-X-SH (3)
H- [O (YO) _n ] -H (4)
[In General Formulas (2), (3) and (4), A is an alkoxy group having 1 to 3 carbon atoms or a chlorine atom, B is an alkyl group having 1 to 3 carbon atoms, and X and Y are each independently a carbon number. 1 to 9 alkanediyl group or alkenediyl group or arylene group having 6 to 15 carbon atoms, and X ¹ is a saturated or unsaturated alkyl group having 1 to 20 carbon atoms, or an aryl group or aralkyl group having 6 to 15 carbon atoms. It is. n is an integer of 1 to 4, and may have a distribution. e and f are numbers satisfying the relations of 0 ≦ e ≦ 3, 0 ≦ f ≦ 2, and e + f = 3. ]

[2] At least one metal selected from the group consisting of a titanium compound, a tin compound, a zirconium compound, a bismuth compound and an aluminum compound as the condensation accelerator used in the step (b) in the production of the modified conjugated diene polymer. The rubber composition of [1], which is a compound;
[3] The rubber composition according to the above [2], wherein the condensation accelerator is at least one metal compound selected from alkoxides, carboxylates and acetylacetonate complex salts,
[4] The condensation accelerator is composed of titanium alkoxide, titanium carboxylate, tin carboxylate, bismuth carboxylate, zirconium alkoxide, zirconium carboxylate, aluminum alkoxide and aluminum carboxylate. The rubber composition according to the above [3], which is at least one selected
[5] The above [1] to [4], wherein the alkali metal initiator used in the step (a) in the production of the modified conjugated diene polymer is a hydrocarbyl lithium compound, a lithium amide compound, or a group 1 metal alkoxide. Any rubber composition,
[6] The rubber composition according to the above [5], wherein the Group 1 metal is lithium, sodium, potassium, rubidium or cesium.

[7] The alkoxysilane compound used in step (a) in the production of the modified conjugated diene polymer is represented by the general formula (5)
R ¹ _g -Si- (OR ² ) _4-g (5)
[Wherein, R ¹ and R ² are each independently a monovalent aliphatic hydrocarbon group having 1 to 20 carbon atoms or a monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms; is 2 integer; when R ¹ is a plurality, the plurality of R ¹ each other may be the same or different; when a plurality of OR ² is more OR ² may be the same as or different from each other; The molecule does not contain active protons and onium salts. ]
And / or a partial condensate thereof, and the general formula (6)

[In the formula, A ¹ is (thio) epoxy group, (thio) isocyanate group, imine residue, (thio) carboxylic acid ester residue, carboxylic acid anhydride residue, cyclic tertiary amine residue, acyclic tertiary A monovalent group having at least one functional group selected from an amine residue, a pyridine group, a silazane group and a bisulfide residue; R ³ is a single bond or a divalent hydrocarbon group; R ⁴ and R ⁵ are Each independently represents a monovalent aliphatic hydrocarbon group having 1 to 20 carbon atoms or a monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms, h is an integer of 0 to 2, and R ⁴ is plural. in some cases, may be different even multiple R ⁴ is identical to each other, if the oR ⁵ there is a plurality, the plurality of oR ⁵ may be the same as or different from each other, also in the molecule active proton and onium Does not contain salt. ]
A rubber composition according to any one of the above [1] to [6], which is at least one selected from the group consisting of an alkoxysilane compound and / or a partial condensate thereof,
[8] The rubber composition according to any one of the above [1] to [7], wherein the inorganic filler containing (B) silicic acid contains silica,
[9] The above-mentioned [1] to [8], wherein the modified conjugated diene polymer is a copolymer of 1,3-butadiene and an aromatic vinyl compound, or a homopolymer of 1,3-butadiene or isoprene. Any rubber composition,
[10] The rubber composition according to the above [9], wherein the aromatic vinyl compound is styrene.
[11] The rubber composition according to any one of the above [1] to [10], wherein the glass transition point (Tg) of the modified conjugated diene polymer is 10 ° C. or less.
[12] The rubber composition according to any one of the above [1] to [11], wherein the rubber component (A) comprises a modified conjugated diene polymer and another diene rubber.
[13] A tire using a member containing the rubber composition according to any one of [1] to [12], and [14] the tire according to [13], wherein the member is a tread.
Is to provide.

  According to the present invention, a modified conjugated diene system obtained by reacting an alkoxysilane compound with the active end of a conjugated diene polymer having an alkali metal active end and then performing a condensation reaction using a condensation accelerator. By blending a rubber component containing 10% by mass or more of a polymer, an inorganic filler containing silica, and a specific silane coupling agent in a predetermined ratio, hysteresis loss is reduced and rolling resistance is good. A rubber composition capable of providing a tire and a tire using the rubber composition can be provided.

First, the rubber composition of the present invention will be described.
The rubber composition of the present invention comprises (A) a rubber component containing a modified conjugated diene polymer, (B) an inorganic filler containing silicic acid, and (C) a silane coupling agent. It is a thing.
[(A) Rubber component]
In the rubber composition of the present invention, the rubber component used as the component (A) needs to contain 10% by mass or more of the modified conjugated diene polymer. This is to further reduce the hysteresis loss.

(Modified conjugated diene polymer)
This modified conjugated diene polymer is obtained by reacting an alkoxysilane compound with the active terminal of a conjugated diene polymer having an alkali metal active terminal obtained by anionic polymerization using an alkali metal initiator (a). And (b) a step of performing a condensation reaction in the presence of a condensation accelerator composed of a compound of an element belonging to at least one of groups 4, 13, 14, and 15 of the periodic table. Obtained by the method.

<Production of Modified Conjugated Diene Polymer>
In the production of the modified conjugated diene polymer, first, in step (a), the conjugated diene monomer is used alone or copolymerized with another monomer using an alkali metal initiator in a hydrocarbon solvent. To produce an conjugated diene polymer having an alkali metal active terminal, usually having a vinyl content of 10% or more, and an alkoxysilane compound at the alkali metal active terminal of the resulting conjugated diene polymer. A denaturation reaction is carried out.
The conjugated diene polymer having an alkali metal active terminal is obtained by copolymerizing a conjugated diene monomer alone or with other monomers, and the production method is not particularly limited. Either a gas phase polymerization method or a bulk polymerization method can be used, but a solution polymerization method is particularly preferable. Moreover, any of a batch type and a continuous type may be sufficient as the superposition | polymerization form.
The active site metal present in the molecule of the conjugated diene polymer is preferably one selected from alkali metals, and lithium metal is particularly preferable.

Examples of the conjugated diene monomer include 1,3-butadiene; isoprene; 1,3-pentadiene; 2,3-dimethylbutadiene; 2-phenyl-1,3-butadiene; 1,3-hexadiene. These may be used alone or in combination of two or more, and among these, 1,3-butadiene and isoprene are particularly preferable.
On the other hand, an aromatic vinyl compound can be mentioned as another monomer used for copolymerization with these with a conjugated diene monomer. Examples of the aromatic vinyl compound include styrene, α-methylstyrene, 1-vinylnaphthalene, 3-vinyltoluene, ethylvinylbenzene, divinylbenzene, 4-cyclohexylstyrene, 2,4,6-trimethylstyrene, and the like. Styrene is particularly preferable.

  Furthermore, when copolymerization is performed using a conjugated diene compound and an aromatic vinyl compound as monomers, the use of 1,3-butadiene and styrene, respectively, in terms of practicality such as the availability of monomers, And anionic polymerization characteristics are particularly preferred in view of the living property. In the case of solution polymerization, the concentration of the monomer in the solution is preferably in the range of 5 to 50% by mass, and more preferably in the range of 10 to 30% by mass. In addition, when using together a conjugated diene compound and an aromatic vinyl compound as a monomer, the content rate of the aromatic vinyl compound in a monomer mixture has the preferable range of 3-50 mass%, and 4-45 mass%. The range of is more preferable.

In this anionic polymerization, it is preferable to use a hydrocarbyl lithium compound, a lithium amide compound or a Group 1 metal alkoxide as the alkali metal initiator. Examples of the Group 1 metal of the Group 1 metal alkoxide include lithium, sodium, potassium, rubidium, and cesium. When a hydrocarbyl lithium compound is used as a polymerization initiator, a conjugated diene polymer having a hydrocarbyl group at the polymerization initiation terminal and the other terminal being a polymerization active site is obtained. On the other hand, when a lithium amide compound is used as a polymerization initiator, a conjugated diene polymer having a nitrogen-containing functional group at the polymerization initiation terminal and the other terminal being a polymerization active site is obtained.
In addition, the usage-amount as a polymerization initiator of organolithium compounds, such as a hydrocarbyl lithium compound and a lithium amide compound, or a group 1 metal alkoxide has the preferable range of 0.2-20 mmol (mmol) per 100g of monomers.

  Examples of the hydrocarbyl lithium compound include ethyl lithium, n-propyl lithium, isopropyl lithium, n-butyl lithium, sec-butyl lithium, tert-octyl lithium, n-decyl lithium, phenyl lithium, 2-naphthyl lithium, and 2-butylphenyl. Examples include lithium, 4-phenyl-butyllithium, cyclohexyllithium, cyclopentyllithium, reaction products of diisopropenylbenzene and butyllithium, and among these, ethyllithium, n-propyllithium, isopropyllithium, n-butyl Alkyl lithium such as lithium, sec-butyl lithium, tert-octyl lithium and n-decyl lithium is preferable, and n-butyl lithium is particularly preferable.

  On the other hand, the lithium amide compounds include lithium hexamethylene imide, lithium pyrrolidide, lithium piperidide, lithium heptamethylene imide, lithium dodecamethylene imide, lithium dimethylamide, lithium diethylamide, lithium dipropylamide, lithium dibutylamide, lithium Dihexylamide, lithium diheptylamide, lithium dioctylamide, lythym-2-ethylhexylamide, lithium didecylamide, lithium-N-methylpiperazide, lithium ethylpropylamide, lithium ethylbutyramide, lithium methylbutyramide, lithium ethylbenzylamide, Examples include lithium methylphenethylamide.

  The lithium amide compound may be preliminarily prepared from a secondary amine and a lithium compound and used for the polymerization reaction, but may be generated in a polymerization system. Here, as the secondary amine, in addition to dimethylamine, diethylamine, dibutylamine, dioctylamine, dicyclohexylamine, diisobutylamine and the like, azacycloheptane (ie, hexamethyleneimine), 2- (2-ethylhexyl) pyrrolidine, 3 -(2-propyl) pyrrolidine, 3,5-bis (2-ethylhexyl) piperidine, 4-phenylpiperidine, 7-decyl-1-azacyclotridecane, 3,3-dimethyl-1-azacyclotetradecane, 4- Dodecyl-1-azacyclooctane, 4- (2-phenylbutyl) -1-azacyclooctane, 3-ethyl-5-cyclohexyl-1-azacycloheptane, 4-hexyl-1-azacycloheptane, 9-isoamyl -1-Azacycloheptadecane, 2-methyl-1-aza Chloheptade-9-ene, 3-isobutyl-1-azacyclododecane, 2-methyl-7-tert-butyl-1-azacyclododecane, 5-nonyl-1-azacyclododecane, 8- (4′-methylphenyl) ) -5-pentyl-3-azabicyclo [5.4.0] undecane, 1-butyl-6-azabicyclo [3.2.1] octane, 8-ethyl-3-azabicyclo [3.2.1] octane, 1-propyl-3-azabicyclo [3.2.2] nonane, 3- (t-butyl) -7-azabicyclo [4.3.0] nonane, 1,5,5-trimethyl-3-azabicyclo [4. 4.0] cyclic amines such as decane.

  As a method for producing a conjugated diene polymer having an alkali metal active terminal by anionic polymerization using the alkali metal initiator, there is no particular limitation, for example, in a hydrocarbon solvent inert to the polymerization reaction, A conjugated diene polymer can be produced by polymerizing a conjugated diene compound alone or a mixture of a conjugated diene compound and an aromatic vinyl compound. Here, as the hydrocarbon solvent inert to the polymerization reaction, 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 anionic polymerization may be performed in the presence of a randomizer. The randomizer can control the microstructure of the conjugated diene compound. For example, the randomizer can control the 1,2-bond content of a butadiene unit in a polymer using butadiene as a monomer, or can be styrene as a monomer. And butadiene units of a copolymer using butadiene are randomized.
Examples of the randomizer include dimethoxybenzene, tetrahydrofuran, dimethoxyethane, diethylene glycol dibutyl ether, diethylene glycol dimethyl ether, bistetrahydrofurylpropane, triethylamine, pyridine, N-methylmorpholine, N, N, N ′, N′-tetramethylethylenediamine, 1 , 2-dipiperidinoethane, potassium t-amylate, potassium t-butoxide, sodium t-amylate and the like. The amount of these randomizers used is preferably in the range of 0.01 to 100 molar equivalents per mole of the organic alkali metal compound as the polymerization initiator.

  The polymerization temperature of the anionic polymerization is preferably in the range of 0 to 150 ° C, more preferably in the range of 20 to 130 ° C. The polymerization can be carried out under generated pressure, but it is usually preferable to carry out the polymerization under a pressure sufficient to keep the monomer used in a substantially liquid phase. Here, when the polymerization reaction is carried out under a pressure higher than the generated pressure, it is preferable to pressurize the reaction system with an inert gas. In addition, it is preferable to use raw materials such as monomers, polymerization initiators, and solvents used for polymerization from which reaction inhibitors such as water, oxygen, carbon dioxide, and protic compounds have been removed in advance.

In the present invention, an alkoxysilane compound (hereinafter sometimes referred to as “modifier”) is allowed to react with the active end of the conjugated diene polymer having an alkali metal active end thus obtained. Perform denaturation reaction.
Although there is no restriction | limiting in particular as this alkoxysilane compound, For example, General formula (5)
R ¹ _g -Si- (OR ² ) _4-g (5)
[Wherein, R ¹ and R ² are each independently a monovalent aliphatic hydrocarbon group having 1 to 20 carbon atoms or a monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms; is 2 integer; when R ¹ is a plurality, the plurality of R ¹ each other may be the same or different; when a plurality of OR ² is more OR ² may be the same as or different from each other; The molecule does not contain active protons and onium salts. ]
And / or a partial condensate thereof, and the general formula (6)

[In the formula, A ¹ is (thio) epoxy group, (thio) isocyanate group, imine residue, (thio) carboxylic acid ester residue, carboxylic acid anhydride residue, cyclic tertiary amine residue, acyclic tertiary A monovalent group having at least one functional group selected from an amine residue, a pyridine group, a silazane group and a bisulfide residue; R ³ is a single bond or a divalent hydrocarbon group; R ⁴ and R ⁵ are Each independently represents a monovalent aliphatic hydrocarbon group having 1 to 20 carbon atoms or a monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms, h is an integer of 0 to 2, and R ⁴ is plural. in some cases, may be different even multiple R ⁴ is identical to each other, if the oR ⁵ there is a plurality, the plurality of oR ⁵ may be the same as or different from each other, also in the molecule active proton and onium Does not contain salt. ]
In particular, at least one selected from the group consisting of alkoxysilane compounds and / or partial condensates thereof is preferably used.
Here, the partial condensate refers to a product in which a part (not all) of the SiOR groups of the alkoxysilane compound are bonded by SiOSi by condensation.
In the above modification reaction, it is preferable that the polymer to be used has at least 10% of the polymer chain having a living property.

In the general formula (5), R ¹ and R ² are each independently, specifically, an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aryl group having 6 to 18 carbon atoms, Examples thereof include aralkyl groups having 7 to 18 carbon atoms. Here, the alkyl group and alkenyl group may be linear, branched, or cyclic, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group. , Sec-butyl, tert-butyl, pentyl, hexyl, octyl, decyl, dodecyl, cyclopentyl, cyclohexyl, vinyl, propenyl, allyl, hexenyl, octenyl, cyclo A pentenyl group, a cyclohexenyl group, etc. are mentioned. The aryl group may have a substituent such as a lower alkyl group on the aromatic ring, and examples thereof include a phenyl group, a tolyl group, a xylyl group, and a naphthyl group. Furthermore, the aralkyl group may have a substituent such as a lower alkyl group on the aromatic ring, and examples thereof include a benzyl group, a phenethyl group, and a naphthylmethyl group.

  Examples of the alkoxysilane compound represented by the general formula (5) include tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetraisopropoxysilane, tetra-n-butoxysilane, tetraisobutoxysilane, Tetra-sec-butoxysilane, tetra-tert-butoxysilane, methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxysilane, methyltriisopropoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, propyltriethoxysilane, Butyltrimethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, dimethyldimethoxysilane, methylphenyldimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane Emissions, divinyl dimethoxysilane, divinyl diethoxy silane and the like, and among them, tetraethoxysilane is particularly preferred.

In the general formula (6), among the functional groups in A ¹ , the imine residue includes a ketimine group, an aldimine residue, and an amidine group, and the (thio) carboxylic acid ester residue is an acrylate residue or a methacrylate residue. Includes unsaturated carboxylic acid ester residues such as groups.
R ⁴ and R ⁵ are each independently, more specifically, an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aryl group having 6 to 18 carbon atoms, and an aralkyl having 7 to 18 carbon atoms. Groups and the like. Here, the alkyl group and alkenyl group may be linear, branched, or cyclic, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group. , Sec-butyl, tert-butyl, pentyl, hexyl, octyl, decyl, dodecyl, cyclopentyl, cyclohexyl, vinyl, propenyl, allyl, hexenyl, octenyl, cyclo A pentenyl group, a cyclohexenyl group, etc. are mentioned. The aryl group may have a substituent such as a lower alkyl group on the aromatic ring, and examples thereof include a phenyl group, a tolyl group, a xylyl group, and a naphthyl group. Furthermore, the aralkyl group may have a substituent such as a lower alkyl group on the aromatic ring, and examples thereof include a benzyl group, a phenethyl group, and a naphthylmethyl group.

The divalent hydrocarbon group in R ³ is preferably an alkylene group having 1 to 20 carbon atoms. The alkylene group may be linear, branched or cyclic, but a linear one is particularly preferable. Examples of the linear alkylene group include a methylene group, an ethylene group, a trimethylene group, a tetramethylene group, a pentamethylene group, a hexamethylene group, an octamethylene group, a decamethylene group, and a dodecamethylene group.

  As the alkoxysilane compound represented by the general formula (6), for example, as a (thio) epoxy group-containing alkoxysilane compound, 2-glycidoxyethyltrimethoxysilane, 2-glycidoxyethyltriethoxysilane, (2 -Glycidoxyethyl) methyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, (3-glycidoxypropyl) methyldimethoxysilane, 2- (3,4-epoxy Cyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane, 2- (3,4-epoxycyclohexyl) ethyl (methyl) dimethoxysilane and the epoxy group in these compounds are replaced with thioepoxy groups Can be mentioned, but these Among them, 3-glycidoxypropyltrimethoxysilane and 3-glycidoxypropyl triethoxysilane are particularly preferred.

  Examples of the (thio) isocyanate group-containing compound include 3-isocyanatopropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-isocyanatopropylmethyldiethoxysilane, and 3-isocyanatopropyltriisopropoxysilane. Among these, 3-isocyanatopropyltriethoxysilane is preferable.

  Further, as the imine residue-containing alkoxysilane compound, N- (1,3-dimethylbutylidene) -3- (triethoxysilyl) -1-propanamine, N- (1-methylethylidene) -3- (triethoxy Silyl) -1-propanamine, N-ethylidene-3- (triethoxysilyl) -1-propanamine, N- (1-methylpropylidene) -3- (triethoxysilyl) -1-propanamine, N- (4-N, N-dimethylaminobenzylidene) -3- (triethoxysilyl) -1-propanamine, N- (cyclohexylidene) -3- (triethoxysilyl) -1-propanamine and their triethoxy Trimethoxysilyl compounds corresponding to silyl compounds, methyldiethoxysilyl compounds, ethyldiethoxysilyl compounds, methyldimethoxysilyl compounds, ethyldi Examples include methoxysilyl compounds, among which N- (1-methylpropylidene) -3- (triethoxysilyl) -1-propanamine and N- (1,3-dimethylbutylidene)- 3- (Triethoxysilyl) -1-propanamine is particularly preferred.

  Examples of the alkoxysilane compound containing amidine partial structure include N- [3- (trimethoxysilyl) propyl] -4,5-dihydroimidazole and N- (3-triethoxysilylpropyl) -4,5-dihydroimidazole. N- (3-isopropoxysilylpropyl) -4,5-dihydroimidazole, N- (3-methyldiethoxysilylpropyl) -4,5-dihydroimidazole and the like, among these, N- (3 -Triethoxysilylpropyl) -4,5-dihydroimidazole is preferred.

Further, as alkoxysilane compounds containing carboxylic acid ester residues, 3-methacryloyloxypropyltriethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-methacryloyloxypropylmethyldiethoxysilane, 3-methacryloyloxypropyl Examples include triisopropoxysilane, among which 3-methacryloyloxypropyltrimethoxysilane is preferable.
Examples of the alkoxysilane compound containing a carboxylic acid anhydride residue include 3-triethoxysilylpropyl succinic anhydride, 3-trimethoxysilylpropyl succinic anhydride, 3-methyldiethoxysilylpropyl succinic anhydride, and the like. Among these, 3-triethoxysilylpropyl succinic anhydride is preferable.

  Examples of the alkoxysilane compound containing a cyclic tertiary amine residue include 3- (1-hexamethyleneimino) propyltriethoxysilane, 3- (1-hexamethyleneimino) propyltrimethoxysilane, and (1-hexamethyleneimino). Methyltriethoxysilane, (1-hexamethyleneimino) methyltrimethoxysilane, 2- (1-hexamethyleneimino) ethyltriethoxysilane, 3- (1-hexamethyleneimino) ethyltrimethoxysilane, 3- (1- Pyrrolidinyl) propyltrimethoxysilane, 3- (1-pyrrolidinyl) propyltriethoxysilane, 3- (1-heptamethyleneimino) propyltriethoxysilane, 3- (1-dodecamethyleneimino) propyltriethoxysilane, 3- ( 1-hexamethyleneimino) pro Examples include rudiethoxymethylsilane, 3- (1-hexamethyleneimino) propyldiethoxyethylsilane, and 3- [10- (triethoxysilyl) decyl] -4-oxazoline. Among these, 3 Preferred examples include-(1-hexamethyleneimino) propyltriethoxysilane and (1-hexamethyleneimino) methyltriethoxysilane.

Examples of the acyclic tertiary amine residue-containing alkoxysilane compound include 3-dimethylaminopropyltriethoxysilane, 3-dimethylaminopropyltrimethoxysilane, 3-diethylaminopropyltriethoxysilane, and 2-dimethylaminoethyltriethoxysilane. , 2-dimethylaminoethyltrimethoxysilane, 3-dimethylaminopropyldiethoxymethylsilane, 3-dibutylaminopropyltriethoxysilane, etc., among which 3-dimethylaminopropyltriethoxysilane and 3-diethylamino Propyltriethoxysilane is preferred.
Examples of the pyridine group-containing alkoxysilane compound include 2-trimethoxysilylethylpyridine.

  Examples of the silazane group-containing alkoxysilane compound include N, N-bis (trimethylsilyl) aminopropylmethyldimethoxysilane, 1-trimethylsilyl-2,2-dimethoxy-1-aza-2-silacyclopentane, and N, N. -Bis (trimethylsilyl) aminopropyltrimethoxysilane, N, N-bis (trimethylsilyl) aminopropyltriethoxysilane, N, N-bis (trimethylsilyl) aminopropylmethyldiethoxysilane, N, N-bis (trimethylsilyl) aminoethyl Trimethoxysilane, N, N-bis (trimethylsilyl) aminoethyltriethoxysilane, N, N-bis (trimethylsilyl) aminoethylmethyldimethoxysilane and N, N-bis (trimethylsilyl) aminoethylmethyldiethoxy Or the like, preferably N, N-bis (trimethylsilyl) aminopropyltriethoxysilane, N, N-bis (trimethylsilyl) aminopropylmethyldiethoxysilane or 1-trimethylsilyl-2,2-dimethoxy- 1-aza-2-silacyclopentane.

  Examples of the bisulfide residue-containing alkoxysilane compound include bis (3-triethoxysilylpropyl) disulfide, bis (3-trimethoxysilylpropyl) disulfide, bis (3-methyldiethoxysilylpropyl) disulfide, and bis (3-methyl). Dimethoxysilylpropyl) disulfide, bis (2-triethoxysilylethyl) disulfide, bis (2-trimethoxysilylethyl) disulfide, bis (2-methyldiethoxysilylethyl) disulfide, bis (2-methyldimethoxysilylethyl) disulfide And compounds in which the disulfides of these compounds are replaced with trisulfides and tetrasulfides.

In the present invention, as the alkoxysilane compound to be reacted as a modifier on the active terminal of the conjugated diene polymer having an alkali metal active terminal, one compound represented by the general formula (5) may be used. Two or more types may be used in combination, and one type of the compound represented by the general formula (6) may be used, or two or more types may be used in combination. Or you may use combining 1 or more types of compounds represented by General formula (5), and 1 or more types of compounds represented by General formula (6). Moreover, the partial condensate of these alkoxysilane compounds can also be used.
The modification reaction with the modifying agent is preferably performed by a solution reaction, and the solution may contain a monomer used during polymerization. The reaction mode of the modification reaction is not particularly limited, and may be a batch type or a continuous type. Furthermore, the reaction temperature of the modification reaction is not particularly limited as long as the reaction proceeds, and the reaction temperature of the polymerization reaction may be employed as it is. In addition, the usage-amount of modifier | denaturant has the preferable range of 0.25-3.0 mol with respect to 1 mol (mol) of polymerization initiators used for manufacture of a conjugated diene polymer, 0.5-1.5 mol A range is more preferred.

In the production of the modified conjugated diene polymer, after performing the modification reaction in the step (a) or in the middle of the modification reaction, the condensation reaction in the presence of the condensation accelerator in the step (b). I do.
In the present invention, a condensation accelerator is used to accelerate the condensation reaction involving the alkoxysilane compound used as the modifier. As the condensation accelerator, a compound of an element belonging to at least one of Group 4, Group 13, Group 14 and Group 15 of the periodic table is used.
As the condensation accelerator, at least one selected from a titanium compound, a tin compound, a diliconium compound, a bismuth compound, and an aluminum compound is preferably used, and more preferably, the alkoxide or carboxyl of each of the above elements. Acid salt and acetylacetonate complex salt, more preferably titanium alkoxide, titanium carboxylate, tin carboxylate, bismuth carboxylate, zirconium alkoxide, zirconium carboxylate, aluminum alkoxide and It is an aluminum carboxylate.

  As the condensation accelerator comprising a titanium compound, 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-butoxytitanium, tetra-tert-butoxytitanium, bis (oleate) bis (2-ethylhexanoate) titanium, titanium dipropoxybis (triethanolamate), titanium dibutoxybis (triethanolaminine) G), titanium tributoxy systemate, titanium tripropoxy systemate, titanium tripropoxyacetylacetonate, titanium dipropoxybis (acetylacetonate), titanium tripropoxy (ethylacetoacetate), titaniumpropoxyacetylacetonatebis (ethylacetate) Acetate), titanium tributoxyacetylacetonate, titanium dibutoxybis (acetylacetonate), titanium tributoxyethylacetoacetate, titaniumbutoxyacetylacetonatebis (ethylacetoacetate), titanium tetrakis (acetylacetonate), titanium diacetylacetate Bis (ethyl acetoacetate), bis (2-ethylhexanoate) titanium oxide, bis (laurate) titanium oxide, bis ( Naphthate) titanium oxide, bis (stearate) titanium oxide, bis (oleate) titanium oxide, bis (linoleate) titanium oxide, tetrakis (2-ethylhexanoate) titanium, tetrakis (laurate) titanium, tetrakis (naphthate) titanium, Tetrakis (stearate) titanium, Tetrakis (oleate) titanium, Tetrakis (linoleate) titanium, Titanium di-n-butoxide (bis-2,4-pentanedionate), Titanium oxide bis (tetramethylheptanedionate), Titanium oxide bis (Pentandionate), titanium tetra (lactate), and the like. Among these, tetrakis (2-ethyl-1,3-hexanediolato) titanium, tetrakis (2-ethylhexoxy) titanium, and titanium di-n-butoxide (bis-2,4-pentanedionate) are preferable.

As the condensation accelerator made of a tin compound, for example, divalent tin carboxylate and tetravalent dihydrocarbyltin dicarboxylate can be preferably exemplified, and bis (2-ethylhexanoic acid) tin is particularly preferable. It is.
Examples of the condensation accelerator composed of a bismuth compound include tris (2-ethylhexanoate) bismuth, tris (laurate) bismuth, tris (naphthate) bismuth, tris (stearate) bismuth, tris (oleate) bismuth, tris ( Linoleate) bismuth. Of these, tris (2-ethylhexanoate) is preferred.

  Examples of the condensation accelerator made of a zirconium compound include tetraethoxyzirconium, tetran-propoxyzirconium, tetraisopropoxyzirconium, tetran-butoxyzirconium, tetrasec-butoxyzirconium, tetratert-butoxyzirconium, tetra (2-ethylhexoxy). Zirconium, zirconium tributoxy systemate, zirconium tributoxyacetylacetonate, zirconium dibutoxybis (acetylacetonate), zirconium tributoxyethylacetoacetate, zirconium butoxyacetylacetonatebis (ethylacetoacetate), zirconium tetrakis (acetylacetonate) ), Zirconium diacetylacetonate bis (ethylacetoacetate) Bis (2-ethylhexanoate) zirconium oxide, bis (laurate) zirconium oxide, bis (naphthate) zirconium oxide, bis (stearate) zirconium oxide, bis (oleate) zirconium oxide, bis (linoleate) zirconium oxide, tetrakis ( Examples include 2-ethylhexanoate) zirconium, tetrakis (laurate) zirconium, tetrakis (naphthate) zirconium, tetrakis (stearate) zirconium, tetrakis (oleate) zirconium, tetrakis (linoleate) zirconium and the like. Among these, tetra n-propoxyzirconium, bis (2-ethylhexanoate) zirconium oxide, bis (oleate) zirconium oxide, and zirconium tetrakis (acetylacetonate) are preferable.

Examples of the condensation accelerator composed of an aluminum compound include 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 (naphthate) aluminum, Squirrel (stearate) aluminum, tris (oleate) aluminum, and tris (linolate) aluminum.
Among these, triisopropoxyaluminum, trisec-butoxyaluminum, tris (2-ethylhexanoate) aluminum, tris (stearate) aluminum, and aluminum tris (acetylacetonate) are preferable.

The amount of the condensation accelerator used is preferably such that the number of moles of the compound is 0.1 to 10 as the molar ratio to the total amount of hydrocarbyloxy groups present in the reaction system, and 0.5 to 5 is preferred. Particularly preferred. By setting the use amount of the condensation accelerator within the above range, the condensation reaction proceeds efficiently.
The addition time of the condensation accelerator is 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.

The condensation reaction in the present invention is preferably performed in the presence of water, and the temperature during the condensation reaction is preferably 20 to 180 ° C, more preferably 30 to 180 ° C, still more preferably 80 to 170 ° C, and particularly preferably 80. ~ 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 usually about 5 minutes to 10 hours, preferably about 15 minutes to 5 hours. By setting the condensation reaction time within the above range, the condensation reaction can be completed smoothly.
In addition, the pressure of the reaction system at the time of condensation reaction is 0.01-20 Mpa normally, Preferably it is 0.05-10 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 a desolvent simultaneously.
The modified conjugated diene polymer thus obtained preferably has a glass transition point (Tg) of 10 ° C. or lower. This is because if Tg is 10 ° C. or lower, the rolling resistance can be further reduced and the flexibility of the rubber composition at low temperatures can be increased.

((A) Composition of rubber component)
In the rubber composition of the present invention, the rubber component used as the component (A) is the modified conjugated diene polymer alone or contains 10% by mass or more of the modified conjugated diene polymer and another diene rubber.
The rubber component needs to contain the modified conjugated diene polymer in an amount of 10% by mass or less. When the content is less than 10% by mass, the effect of improving the dispersibility of the (B) reinforcing filler is small, and the rubber composition work This is because the effect of improving the heat resistance, the low heat generation property, the fracture property and the wear resistance is small. In this respect, 20% by mass or more is preferable, and 30% by mass or more is more preferable.
In the rubber composition of the present invention, other diene rubbers other than the modified conjugated diene polymer are natural rubber (NR), unmodified styrene-butadiene copolymer (SBR), and polybutadiene rubber. (BR), polyisoprene rubber (IR), butyl rubber (IIR), ethylene-propylene-diene terpolymer (EPDM) and the like can be used, and among these, natural rubber and polyisoprene rubber are preferable. These rubber components may be used alone or as a blend of two or more.

[(B) Inorganic filler containing silicic acid]
In the rubber composition of the present invention, the inorganic filler containing silicic acid used as the component (B) is silica, clay (Al ₂ O ₃ .2SiO ₂ ), kaolin (Al ₂ O ₃ .2SiO ₂ .2H _2). O), pyrophyllite (Al ₂ O ₃ · 4SiO ₂ · H ₂ O), bentonite (Al ₂ O ₃ · 4SiO ₂ · 2H ₂ O), aluminum silicate (Al ₂ SiO ₅ , Al ₄ · 3SiO ₄ · 5H ₂ O etc.), magnesium silicate (Mg ₂ SiO ₄ , MgSiO ₃ etc.), calcium silicate (Ca ₂ SiO ₄ etc.), aluminum calcium silicate (Al ₂ O ₃ · CaO · 2SiO ₂ etc.), silicic acid Examples thereof include magnesium calcium (CaMgSiO ₄ ), crystalline aluminosilicate containing hydrogen, alkali metal, or alkaline earth metal that corrects electric charge, such as various zeolites.
Of these, silica is preferred. As silica, wet silica and dry silica are preferable, and wet silica is more preferable.

  The said inorganic filler needs to mix | blend 10-140 mass parts with respect to 100 mass parts of rubber components. If the amount is less than 10 parts by mass, the fracture characteristics and wear resistance of the rubber composition will be reduced. On the other hand, when it exceeds 140 parts by mass, the loss tangent of the rubber composition increases, and the rolling resistance of the tire increases. From these viewpoints, the content is preferably 15 to 120 parts by mass, and more preferably 20 to 110 parts by mass.

[(C) Silane coupling agent]
In the rubber composition of this invention, a silane coupling agent is contained as (C) component. As this silane coupling agent, the following general formula (1)
A _a B _b D _c Si—X—S—CO—X ¹ (1)
And / or a compound represented by the following general formula (2) and / or a compound represented by the following general formula (3) and a diol compound represented by the following general formula (4): It is characterized by being a compound formed.
A _e B _f Si—XS—CO—X ¹ (2)
A _e B _f Si-X-SH (3)
H- [O (YO) _n ] -H (4)

In General formula (1), A shows a C1-C3 alkoxy group or a chlorine atom, B shows a C1-C3 alkyl group. X represents an alkanediyl group or alkenediyl group having 1 to 9 carbon atoms or an arylene group having 6 to 15 carbon atoms, for example, a linear or branched alkylene group having 1 to 9 carbon atoms, a straight chain having 2 to 9 carbon atoms, Examples thereof include a chain or branched alkenylene group, a cycloalkylene group having 4 to 9 carbon atoms, a cycloalkylalkylene group having 5 to 9 carbon atoms, and an unsubstituted or substituted phenylene group having 6 to 15 carbon atoms. As this X, a C1-C6 alkylene group is preferable, and especially a linear alkylene group, for example, a methylene group, ethylene group, trimethylene group, tetramethylene group, pentamethylene group, hexamethylene group can be mentioned preferably. .
X ¹ is a saturated or unsaturated alkyl group having 1 to 20 carbon atoms, or an aryl group or aralkyl group having 6 to 15 carbon atoms. D represents A, B, or — [O (XO) _n ] _0.5 — group, n may be an integer of 1 to 4 and may have a distribution, and X is the same as described above. a, b, and c are numbers satisfying the relationship of 0 ≦ a ≦ 3, 0 ≦ b ≦ 2, 0 ≦ c ≦ 1.5, and a + b + 2c = 3.

In the general formulas (2), (3) and (4), A is an alkoxy group having 1 to 3 carbon atoms or a chlorine atom, B is an alkyl group having 1 to 3 carbon atoms, and X and Y are each independently 1 carbon atom. An alkanediyl group or an alkenediyl group having 9 to 9 carbon atoms or an arylene group having 6 to 15 carbon atoms, and X ¹ is a saturated or unsaturated alkyl group having 1 to 20 carbon atoms, or an aryl group or aralkyl group having 6 to 15 carbon atoms. is there. n is an integer of 1 to 4, and may have a distribution. e and f are numbers satisfying the relations of 0 ≦ e ≦ 3, 0 ≦ f ≦ 2, and e + f = 3.
X and Y are each independently preferably an alkylene group having 1 to 6 carbon atoms, particularly a linear alkylene group such as a methylene group, an ethylene group, a trimethylene group, a tetramethylene group, a pentamethylene group, or a hexamethylene group. Can be preferably mentioned.

  Examples of the silane coupling agent represented by the general formula (1) include 3-hexanoylthiopropyltriethoxysilane, 3-octanoylthiopropyltriethoxysilane, 3-decanoylthiopropyltriethoxysilane, 3 -Lauroylthiopropyltriethoxysilane, 2-hexanoylthioethyltriethoxysilane, 2-octanoylthioethyltriethoxysilane, 2-decanoylthioethyltriethoxysilane, 2-lauroylthioethyltriethoxysilane, 3-hexa Noylthiopropyltrimethoxysilane, 3-octanoylthiopropyltrimethoxysilane, 3-decanoylthiopropyltrimethoxysilane, 3-lauroylthiopropyltrimethoxysilane, 2-hexanoylthioethyltrimethoxysilane, 2- Kuta Neu Lucio ethyltrimethoxysilane, 2- deca Neu thio ethyltrimethoxysilane, 2- lauroyl thio ethyltrimethoxysilane, include compounds represented by the following chemical formula (7).

Examples of the compound obtained by reacting the compound represented by the general formula (2) and / or the compound represented by the general formula (3) with the diol compound represented by the general formula (4) , 3-octanoylthiopropyltriethoxysilane and / or 3-mercaptopropyltriethoxysilane and condensates of the following diol compounds. Here, as the diol compound, 2-methyl-2,4-pentanediol, neopentyl glycol, ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, 1,3-butanediol, 1,4-butanediol, 2 -Methyl-1,3-propanediol, 2,2-dimethyl-1,3-propanediol and the like.
Specific examples of the compound obtained by reacting the compound represented by the general formula (2) and / or the compound represented by the general formula (3) with the diol compound represented by the general formula (4) Is, for example, a compound represented by the following chemical formula (8).
The silane coupling agents described above may be used alone or in combination of two or more.

The silane coupling agent of component (C) has a strong action of hydrophobizing the silica surface of the reinforcing filler and reducing the cohesive strength of the silica during kneading in the preparation of the rubber composition.
On the other hand, in the modified conjugated diene polymer modified with an alkoxysilane compound blended in the rubber component (A), the modified functional group and silica are covalently bonded during kneading, and the silica is dispersed by shearing force. This dispersing action is more effectively exhibited by adding a condensation accelerator to advance the condensation reaction during the production of the modified conjugated diene polymer. Moreover, because of the action of the silane coupling agent, the silica has a reduced cohesive force, so that the dispersion effect by the modified conjugated diene polymer is very excellent, and the hysteresis loss of the resulting rubber composition Is effectively reduced, and a tire with good rolling resistance can be obtained.

In the present invention, the silane coupling agent of component (C) may be used alone or in combination of two or more. Moreover, content of the said silane coupling agent is chosen in the range of 1-20 mass% with respect to the inorganic filler containing the silicic acid of (B) component. If the content is less than 1% by mass, the effect of blending the silane coupling agent may not be sufficiently exhibited. On the other hand, if the content exceeds 20% by mass, the improvement of the effect is not seen for the amount, but rather the economy. Disadvantageous. Considering the blending effect and economy, the preferable content of this silane coupling agent is in the range of 3 to 15% by mass.
In the present invention, as long as the effect of the present invention is not impaired, other known silane coupling agents conventionally used in rubber compositions are optionally used in the silane coupling agent of component (C). It may be replaced with a part.

  Other silane coupling agents include, for example, bis (3-triethoxysilylpropyl) tetrasulfide, bis (3-trimethoxysilylpropyl) tetrasulfide, bis (3-methyldimethoxysilylpropyl) tetrasulfide, bis (3- Triethoxysilylethyl) tetrasulfide, bis (3-triethoxysilylpropyl) disulfide, bis (3-trimethoxysilylpropyl) disulfide, bis (3-triethoxysilylpropyl) trisulfide, and the like, and 3-mercaptopropyl Trimethoxysilane, 3-mercaptopropyltriethoxysilane, vinyltriethoxysilane, vinyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-mercaptop Pyrmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, etc., or 3-trimethoxysilylpropyl-N, N-dimethylcarbamoyl tetrasulfide, 3-trimethoxysilyl It can be appropriately selected from propylbenzothiazolyl tetrasulfide, 3-trimethoxysilylpropylmethacryloyl monosulfide, 3-triethoxysilylpropyl n-octyl disulfide, and the like.

[Preparation of rubber composition]
In the rubber composition of the present invention, in addition to the inorganic filler containing the silicic acid component (B), other fillers such as carbon black, vulcanizing agents, vulcanization accelerators, zinc oxide, stearic acid A compounding agent usually used in the rubber industry such as an anti-aging agent can be appropriately selected and blended within a range not impairing the object of the present invention. As these compounding agents, commercially available products can be suitably used. The rubber composition comprises (B) a rubber component, (B) an inorganic filler containing silicic acid and (C) a silane coupling agent, and various appropriately selected compounding agents. It can be prepared by kneading using a mixer, roll, intensive mixer or the like, followed by heating, extruding, or the like.

[tire]
The tire of the present invention is characterized in that the rubber composition is applied to any of tire members. Here, in the tire of the present invention, it is particularly preferable to use the rubber composition of the present invention for the tread, and the tire using the rubber composition for the tread has low rolling resistance and excellent fuel efficiency. In addition, as gas with which the tire of the present invention is filled, normal or air with a changed oxygen partial pressure, or an inert gas such as nitrogen is exemplified. When the rubber composition of the present invention is used for a tread, for example, it is extruded on a tread member, and is pasted and molded by a usual 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.

Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the following examples.
The loss tangent (tan δ) of the rubber composition after vulcanization, the rolling resistance reduction index of the tire, and the microstructure of the unmodified and modified conjugated diene polymer were evaluated by the following methods.
(1) Loss tangent (tan δ)
Using a viscoelasticity measuring device (Rheometrics), tan δ (60 ° C.) was measured at a temperature of 60 ° C., a strain of 5%, and a frequency of 15 Hz.
Tan δ (60 ° C.) was expressed as an index according to the following equation. The smaller the index value, the smaller the tan δ, the lower the rolling resistance, and the better the fuel efficiency.
Loss tangent index = [(loss tangent of target rubber composition to be compared / loss tangent of rubber composition of Comparative Example 1, 4, 7 or 10)] × 100
(2) Tire rolling resistance reduction index After filling a pneumatic tire of tire size 185 / 70R14 with an internal pressure of 170 kPa, running on a large test drum at a speed of 80 km / h for a predetermined time while applying a load of 395 kg, Next, the driving force of the drum was cut off, and each tire was allowed to travel inertially. The rolling resistance was obtained from the deceleration of the tire at this time, and the index of Comparative Example 1, 4, 7, or 10 was set to 100 and the index was displayed. The larger the index, the lower the rolling resistance.
Index of test tire = [(Rolling resistance of tire of Comparative Example 1, 4, 7 or 10 / Rolling resistance of test tire to be compared)] × 100
(3) Microstructure and bound styrene content The microstructure of each conjugated diene polymer is determined by the infrared method (Morero method), and the bound styrene content of each conjugated diene polymer is determined from the integration ratio of the ¹ H-NMR spectrum. It was.
(4) Glass transition point Using a differential thermal analyzer (DSC) type 7 device manufactured by PerkinElmer, Inc., each conjugated diene polymer was cooled to -100 ° C and then heated at a rate of 10 ° C / min. Then, the glass transition point of each polymer was measured.
(5) Mooney viscosity (ML _{1 +} 4/100 ° C)
According to JIS K6300, measurement was performed under the conditions of an L rotor, preheating for 1 minute, rotor operating time of 4 minutes, and temperature of 100 ° C.

Synthesis Example 1 (Synthesis of Copolymer A):
An autoclave reactor with an internal volume of 5 liters purged with nitrogen was charged with 2,750 g of cyclohexane, 41.3 g of tetrahydrofuran, 125 g of styrene, and 375 g of 1,3-butadiene. 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. The polymer solution in the reactor was sampled in a small amount in 30 g of a cyclohexane solution to which 1 g of methanol was added, and then 600 mg of methyltriethoxysilane was added as a modifier, and the modification reaction was performed for 15 minutes. Thereafter, 3.97 g of bis (2-ethylhexanoic acid) zirconium oxide was added as a condensation accelerator, and the mixture was further stirred for 15 minutes. Finally, 2,5-di-tert-butyl-p-cresol was added to the polymer solution after the reaction. Next, the solvent was removed by steam stripping, and the rubber was dried with a hot roll adjusted to 110 ° C. to obtain a raw rubber copolymer. The composition and physical properties of the obtained copolymer A are shown in Table 1.

Comparative Synthesis Example 1 (Synthesis of Copolymer B)
In Synthesis Example 1, a copolymer B was obtained in the same manner as in Synthesis Example 1 except that the condensation accelerator was not added. The composition and physical properties of the obtained copolymer B are shown in Table 1.

Synthesis Example 2 (Synthesis of copolymer C)
In Synthesis Example 1, the modifier was changed to 803 mg of 3-glycidoxypropyltrimethoxysilane, and 3.97 g of bis (2-ethylhexanoic acid) zirconium oxide was changed to 6.45 g of tris (2-ethylhexanoic acid) bismuth. Except for this, copolymer C was obtained in the same manner as in Synthesis Example 1. The composition and physical properties of the obtained copolymer C are shown in Table 1.

Comparative Synthesis Example 2 (Synthesis of Copolymer D)
In Synthesis Example 2, a copolymer D was obtained in the same manner as in Synthesis Example 2 except that tris (2-ethylhexanoic acid) zirconium was not added. Table 1 shows the composition and physical properties of the obtained copolymer D.

Synthesis Example 3 (Synthesis of Copolymer E)
In Synthesis Example 1, the modifier was changed to 832 mg of 3-isocyanatopropyltrimethoxysilane, and 3.97 g of bis (2-ethylhexanoic acid) zirconium oxide was changed to 6.45 g of tris (2-ethylhexanoic acid) bismuth. Except for the above, a copolymer E was obtained in the same manner as in Synthesis Example 1. Table 1 shows the composition and physical properties of the obtained copolymer E.

Comparative Synthesis Example 3 (Synthesis of Copolymer F)
In Synthesis Example 3, a copolymer F was obtained in the same manner as in Synthesis Example 3, except that tris (2-ethylhexanoic acid) zirconium was not added. The composition and physical properties of the obtained copolymer F are shown in Table 1.

Synthesis Example 4 (Synthesis of copolymer G)
In Synthesis Example 1, the modifier was changed to 1020 mg of N- (1,3-dimethylbutylidene) -3- (triethoxysilyl) -1-propanamine, and the condensation accelerator was bis (2-ethylhexanoic acid) tin. A copolymer G was obtained in the same manner as in Synthesis Example 1 except that the amount was changed to 4.42 mg. Table 1 shows the composition and physical properties of the obtained copolymer G.

Comparative Synthesis Example 4 (Synthesis of copolymer H)
Copolymer H was obtained in the same manner as in Synthesis Example 4 except that bis (2-ethylhexanoic acid) tin was not used in Synthesis Example 4. The composition and physical properties of the obtained copolymer H are shown in Table 1.

Synthesis Example 5 (Synthesis of Copolymer I)
In Synthesis Example 1, the modifier was changed to 1129 mg of N, N-bis (trimethylsilyl) aminopropylmethyldiethoxysilane, and 3.97 g of bis (2-ethylhexanoic acid) zirconium oxide was added to tetrakis (2-ethylhexoxy) titanium. A copolymer I was obtained in the same manner as in Synthesis Example 1 except that the amount was changed to 19 g. Table 1 shows the composition and physical properties of the obtained copolymer I.

Comparative Synthesis Example 5 (Synthesis of Copolymer J)
In Synthesis Example 5, Copolymer J was obtained in the same manner as in Synthesis Example 5 except that tetrakis (2-ethylhexoxy) titanium was not used. The composition and physical properties of the obtained copolymer J are shown in Table 1.

（注）
１）重合反応
シクロヘキサン：２７５０ｇ、テトラヒドロフラン：４１．３ｇ、スチレン：１２５ｇ、ブタジエン：３７５ｇ
２）変性剤
Ｍ−１：メチルトリエトキシシラン
Ｍ−２：３−グリシドキシプロピルトリメトキシシラン
Ｍ−３：３−イソシアネートプロピルトリメトキシシラン
Ｍ−４：Ｎ−（１，３−ジメチルブチリデン）−３−（トリエトキシシリル）−１−プロパンアミン
Ｍ−５：Ｎ，Ｎ−ビス（トリメチルシリル）アミノプロピルメチルジエトキシシラン
３）縮合促進剤
Ｉ：ビス（２−エチルヘキサン酸）酸化ジルコニウム
II：トリス（２−エチルヘキサン酸）ビスマス
III：ビス（２−エチルヘキサン酸）スズ
IV：テトラキス（２−エチルヘキソキシ）チタン

(note)
1) Polymerization reaction Cyclohexane: 2750 g, Tetrahydrofuran: 41.3 g, Styrene: 125 g, Butadiene: 375 g
2) Modifier M-1: Methyltriethoxysilane M-2: 3-glycidoxypropyltrimethoxysilane M-3: 3-isocyanatopropyltrimethoxysilane M-4: N- (1,3-dimethylbutylidene ) -3- (Triethoxysilyl) -1-propanamine M-5: N, N-bis (trimethylsilyl) aminopropylmethyldiethoxysilane 3) Condensation accelerator I: Bis (2-ethylhexanoic acid) zirconium oxide
II: Tris (2-ethylhexanoic acid) bismuth
III: bis (2-ethylhexanoic acid) tin
IV: Tetrakis (2-ethylhexoxy) titanium

Reference Examples 1 and 2 and Comparative Examples 1 to 3
Five types of rubber compositions were prepared by kneading with a Banbury mixer with the compounding recipe shown second. Vulcanized rubber samples were prepared from these five rubber compositions under conditions of a vulcanization temperature of 165 ° C. and a vulcanization time of 15 minutes, and the loss tangent (tan δ) of the vulcanized rubber composition was measured. The results are shown in Table 2.
Next, five types of pneumatic tires of tire size 185 / 70R14 using these five types of rubber compositions as a tread having a single-layer structure were prepared, and the rolling resistance reduction index of the tire was measured by the above evaluation method. The results are shown in Table 2.

＊１：ＪＳＲ株式会社製、ＢＲ０１
＊２：東ソー・シリカ株式会社製、商標「ニプシルＡＱ」
＊３：三菱化学株式会社製、商標「ダイアブラック Ｎ３３９」
＊４：ビス（３−トリエトキシシリルプロピル）テトラスルフィド、デグサ社製シランカップリング剤、商標「Ｓｉ６９」
＊５：Ｍｏｍｅｎｔｉｖｅ Ｐｅｒｆｏｒｍａｎｃｅ Ｍａｔｅｒｉａｌｓ社製、商標「ＮＸＴ Ｚ １００ ｓｉｌａｎｅ」、３−メルカプトプロピルトリエトキシシランのエトキシ基をジオールで置換したシランカップリング剤
＊６：Ｍｏｍｅｎｔｉｖｅ Ｐｅｒｆｏｒｍａｎｃｅ Ｍａｔｅｒｉａｌｓ社製、商標「ＮＸＴ Ｕｌｔｒａ Ｌｏｗ−Ｖ Ｓｉｌａｎｅ」、前記化学式（８）で表される化合物
＊７：精工化学株式会社製、商標「オゾノン６Ｃ」
＊８：大内新興化学工業株式会社製、商標「ノクセラーＤ」
＊９：大内新興化学工業株式会社製、商標「ノクセラーＣＺ」

* 1: BR01 manufactured by JSR Corporation.
* 2: Trademark “Nipsil AQ” manufactured by Tosoh Silica Co., Ltd.
* 3: Trademark “Dia Black N339” manufactured by Mitsubishi Chemical Corporation
* 4: Bis (3-triethoxysilylpropyl) tetrasulfide, Degussa silane coupling agent, trademark “Si69”
* 5: Made by Momentive Performance Materials, trademark “NXT Z 100 silane”, silane coupling agent in which ethoxy group of 3-mercaptopropyltriethoxysilane is substituted with diol * 6: Made by Momentive Performance Materials, trademark “NXL Ultra Ultra -V Silane ", compound represented by the above chemical formula (8) * 7: Seiko Chemical Co., Ltd., trademark" Ozonon 6C "
* 8: Trademark “Noxeller D” manufactured by Ouchi Shinsei Chemical Co., Ltd.
* 9: Trademark “Noxeller CZ” manufactured by Ouchi Shinsei Chemical Industry Co., Ltd.

Reference Example 3 and Comparative Examples 4-6
Four types of rubber compositions were prepared by kneading with a Banbury mixer with the formulation shown in Table 3. Vulcanized rubber samples were prepared from these four rubber compositions under conditions of a vulcanization temperature of 165 ° C. and a vulcanization time of 15 minutes, and the loss tangent (tan δ) of the vulcanized rubber composition was measured. The results are shown in Table 3.
Next, four types of pneumatic tires of tire size 185 / 70R14 using each of these four types of rubber compositions as a tread having a single-layer structure were produced, and the rolling resistance reduction index of the tire was measured by the above evaluation method. The results are shown in Table 3.

＊１０：ＪＳＲ株式会社製、商標「ＩＲ２２００」
＊１１：東ソーシリカ株式会社製、商標「ニプシルＫＱ」
＊１２：Ｎ２３４、東海カーボン株式会社製、商標「シースト７ＨＭ」
＊１３：デグサ社製、商標「Ｓｉ７５」、化学名：ビス（３−トリエトキシシリルプロピル）ジスルフィド
＊１４：Ｍｏｍｅｎｔｉｖｅ Ｐｅｒｆｏｒｍａｎｃｅ Ｍａｔｅｒｉａｌｓ社製、商標「ＮＸＴ Ｌｏｗ−Ｖ Ｓｉｌａｎｅ」、化学名：前記化学式（７）で表される化合物
＊１５：大内新興化学株式会社製、商標「ノクセラーＤＭ」
＊１６：三新化学工業株式会社製、商標「サンセラーＮＳ−Ｇ」
＊７、８：表２の脚注と同じ

* 10: Trademark “IR2200” manufactured by JSR Corporation
* 11: Trademark “Nipsil KQ” manufactured by Tosoh Silica Corporation
* 12: N234, manufactured by Tokai Carbon Co., Ltd., trademark “SEAST 7HM”
* 13: Degussa, trademark “Si75”, chemical name: bis (3-triethoxysilylpropyl) disulfide * 14: Momentive Performance Materials, trademark “NXT Low-V Silane”, chemical name: Chemical formula (7 * 15: Ouchi Shinsei Chemical Co., Ltd., trademark “Noxeller DM”
* 16: Trademark “Sunseller NS-G” manufactured by Sanshin Chemical Industry Co., Ltd.
* 7, 8: Same as footnote in Table 2

Reference Example 4 and Comparative Examples 7-9
Four types of rubber compositions were prepared by kneading with a Banbury mixer with the formulation shown in Table 4. Vulcanized rubber samples were prepared from these four rubber compositions under conditions of a vulcanization temperature of 165 ° C. and a vulcanization time of 15 minutes, and the loss tangent (tan δ) of the vulcanized rubber composition was measured. The results are shown in Table 4.
Next, four types of pneumatic tires of tire size 185 / 70R14 using each of these four types of rubber compositions as a tread having a single-layer structure were produced, and the rolling resistance reduction index of the tire was measured by the above evaluation method. The results are shown in Table 4.

＊１７：Ｎ３３９、東海カーボン株式会社製、商標「シーストＫＨ」
＊１８：Ｍｏｍｅｎｔｉｖｅ Ｐｅｒｆｏｒｍａｎｃｅ Ｍａｔｅｒｉａｌｓ社製、商標「ＮＸＴ Ｓｉｌａｎｅ」、化学名：オクタンチオ酸Ｓ−［３−（トリエトキシシリル）プロピル］エステル
＊２、４、７、８、１５及び１６：表２及び表３の脚注と同じ

* 17: N339, manufactured by Tokai Carbon Co., Ltd., trademark “Seast KH”
* 18: Momentive Performance Materials, trade name “NXT Silane”, chemical name: octanethioic acid S- [3- (triethoxysilyl) propyl] ester * 2, 4, 7, 8, 15 and 16: Table 2 and Table Same as footnote 3

Examples 1 and 2 and Comparative Examples 10-15
Eight types of rubber compositions were prepared by kneading with a Banbury mixer with the formulation shown in Table 5. Vulcanized rubber samples were prepared from these eight rubber compositions under conditions of a vulcanization temperature of 165 ° C. and a vulcanization time of 15 minutes, and the loss tangent (tan δ) of the vulcanized rubber composition was measured. The results are shown in Table 5.
Next, eight types of pneumatic tires having a tire size of 185 / 70R14, each using these eight types of rubber compositions as a tread having a single-layer structure, were produced, and the rolling resistance reduction index of the tire was measured by the above evaluation method. The results are shown in Table 5.

＊１９：Ｌａｎｘｅｓ社製、商標「ＢｕｎａＶＳＬ５０２５−１」
＊２、４、７、８、１４、１５、１６、１７、１８：表２、表３、表４の脚注と同じ
表２〜表５より明らかなように、実施例のゴム組成物はいずれも比較例のゴム組成物に比べて損失正接が低く、タイヤの転がり抵抗が低く良好である。

* 19: Trademark “Buna VSL5025-1” manufactured by Lanxes
* 2, 4, 7, 8, 14, 15, 16, 17, 18: Same as footnotes in Table 2, Table 3, and Table 4, As is clear from Tables 2 to 5, the rubber compositions of the examples The loss tangent is lower than that of the rubber composition of the comparative example, and the rolling resistance of the tire is low and good.

  The rubber composition of the present invention can provide a tire having low hysteresis loss and good rolling resistance.

Claims (13)

(A) A rubber component containing 10% by mass or more of a modified conjugated diene polymer, and 100 parts by mass of (B) 10 to 140 parts by mass of an inorganic filler containing silicic acid, and (C) A rubber composition containing a silane coupling agent in a proportion of 1 to 20% by mass relative to the inorganic filler (B),
(1) The modified conjugated diene polymer, (a) to the active end of the conjugated diene polymer having an alkali metal active end obtained by anionic polymerization using an alkali metal-based initiator represented by the following general formula (6) a step of performing a modification reaction by reacting the alkoxysilane compound represented by (6), and (b) a condensation promotion comprising a compound of an element belonging to at least one of Groups 4, 13, 14, and 15 of the periodic table. And (2) the (C) silane coupling agent is represented by the following general formula (1), and is obtained by a production method including a step of performing a condensation reaction in the presence of an agent.
And / or a compound represented by the following general formula (2) and / or a compound represented by the following general formula (3) and a diol compound represented by the following general formula (4): A rubber composition characterized in that it is a compound obtained.
A _a B _b D _c Si—X—S—CO—X ¹ (1)
[In the formula, A represents an alkoxy group having 1 to 3 carbon atoms or a chlorine atom, B represents an alkyl group having 1 to 3 carbon atoms, X represents an alkanediyl group or alkenediyl group having 1 to 9 carbon atoms, or 6 to 15 carbon atoms. arylene group, X ¹ is an aryl group or an aralkyl group of saturated or unsaturated alkyl group, or a 6 to 15 carbon atoms having 1 to 20 carbon atoms. D is A, B, or — [O (XO) _n ] _0.5 — group, n is an integer of 1 to 4, and may have a distribution. a, b, and c are numbers satisfying the relationship of 0 ≦ a ≦ 3, 0 ≦ b ≦ 2, 0 ≦ c ≦ 1.5, and a + b + 2c = 3. ]
A _e B _f Si—XS—CO—X ¹ (2)
A _e B _f Si-X-SH (3)
H- [O (YO) _n ] -H (4)
[In General Formulas (2), (3) and (4), A is an alkoxy group having 1 to 3 carbon atoms or a chlorine atom, B is an alkyl group having 1 to 3 carbon atoms, and X and Y are each independently a carbon number. 1 to 9 alkanediyl group or alkenediyl group or arylene group having 6 to 15 carbon atoms, and X ¹ is a saturated or unsaturated alkyl group having 1 to 20 carbon atoms, or an aryl group or aralkyl group having 6 to 15 carbon atoms. It is. n is an integer of 1 to 4, and may have a distribution. e and f are numbers satisfying the relations of 0 ≦ e ≦ 3, 0 ≦ f ≦ 2, and e + f = 3. ]

[ Wherein , A ¹ is a monovalent group having an imine residue or a silazane group, R ³ is a single bond or a divalent hydrocarbon group, and R ⁴ and R ⁵ are each independently one having 1 to 20 carbon atoms. indicates the valency of the aliphatic hydrocarbon group or a monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms, h is an integer of 0 to 2, if R ⁴ is plural, R ⁴ is each independently But it may be different, if the oR ⁵ there is a plurality, the plurality of oR ⁵ may be the same as or different from each other, also in the molecule does not include an active proton and an onium salt. ]   The condensation accelerator used in step (b) in the production of the modified conjugated diene polymer is at least one metal compound selected from a titanium compound, a tin compound, a zirconium compound, a bismuth compound, and an aluminum compound. The rubber composition according to claim 1.   The rubber composition according to claim 2, wherein the condensation accelerator is at least one metal compound selected from alkoxides, carboxylates, and acetylacetonate complex salts.   The condensation accelerator is at least selected from titanium alkoxide, titanium carboxylate, tin carboxylate, bismuth carboxylate, zirconium alkoxide, zirconium carboxylate, aluminum alkoxide and aluminum carboxylate The rubber composition according to claim 3, which is one type.   The rubber according to any one of claims 1 to 4, wherein the alkali metal initiator used in step (a) in the production of the modified conjugated diene polymer is a hydrocarbyl lithium compound, a lithium amide compound, or a group 1 metal alkoxide. Composition.   The rubber composition according to claim 5, wherein the Group 1 metal is lithium, sodium, potassium, rubidium or cesium. The rubber composition according to any one of claims 1 to 6 , wherein the inorganic filler containing (B) silicic acid contains silica. The rubber according to any one of claims 1 to 7 , wherein the modified conjugated diene polymer is a copolymer of 1,3-butadiene and an aromatic vinyl compound, or a homopolymer of 1,3-butadiene or isoprene. Composition. The rubber composition according to claim 8 , wherein the aromatic vinyl compound is styrene. The rubber composition according to any one of claims 1 to 9 , wherein the glass transition point (Tg) of the modified conjugated diene polymer is 10 ° C or lower. The rubber composition according to any one of claims 1 to 10 , wherein the rubber component (A) comprises a modified conjugated diene polymer and another diene rubber. Tires made using a member containing a rubber composition according to any one of claims 1 to 1 1. Tire according to claim 1 2 member is a tread.