JP2012172119A - Rubber composition and pneumatic tire using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rubber composition that is especially excellent in interaction between a rubber component and carbon black and/or silica, improves dispersibility of these fillers more, and is excellent in low heat generation and abrasion resistance; and to provide a pneumatic tire obtained by using the composition and having the characteristics described above.SOLUTION: The rubber composition is obtained by blending 10-150 pts.mass of a reinforcing filler (C) and less than 1 pts.mass of an organic acid (D) based on 100 pts.mass of a rubber component comprising 5-90 pts.mass of a modified polymer (A) including a heterofunctional group capable of generating an onium cation by an acid and 95-10 pts.mass of another polymer component (B).

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, providing a tire having good rolling resistance and excellent wear resistance, and a pneumatic tire using the rubber composition.

  In recent years, there has been a demand for improved wear resistance that leads to lower fuel consumption and resource saving of automobiles in connection with the global movement of carbon dioxide emission regulations due to social demands for energy saving and increased interest in environmental issues. Is becoming more severe. In order to meet such demands, a reduction in rolling resistance has also been demanded for tire performance. As a technique for reducing the rolling resistance of the tire, although a technique by optimizing the tire structure has been studied, the most common technique is to use a material having lower heat generation as the rubber composition.

  In order to obtain such a rubber composition having a low exothermic property, many technical developments have been made on modified rubbers for rubber compositions using silica or carbon black as a filler. Among them, a method in which the polymerization active terminal of a conjugated diene polymer obtained by anionic polymerization using organolithium is modified with an alkoxysilane derivative containing a functional group that interacts with a filler has been proposed as effective. (For example, see Patent Documents 1, 2, and 3).

Each of these alkoxysilane derivatives is a silicon compound having an alkoxy group directly bonded to a silicon atom in the molecule and a nitrogen-containing functional group that interacts with the filler. The modified conjugated diene polymer obtained by modification has the effect of reducing the rolling resistance of the tire and improving the fracture characteristics and wear resistance. However, in recent years, from the viewpoints of energy saving and environmental problems, further reduction in fuel consumption of automobiles (reduction in rolling resistance of tires) and improvement in wear resistance are desired.
In addition, it is disclosed that in the emulsion polymerization of styrene-butadiene, the wear resistance is improved by limiting the amount of the emulsifier contained in the polymer to a specific range (1 to 3.5 phr) (for example, Patent Documents 4 and 5).

JP 2002-103925 A WO02 / 002356 brochure JP 2004-74960 A Special table 2003-521574 gazette Special table 2003-521575 gazette

  Under such circumstances, the present invention is particularly excellent in the interaction between the rubber component and carbon black and / or silica, can further improve the dispersibility of these fillers, and has low heat buildup and wear resistance. It is an object of the present invention to provide an excellent rubber composition and a pneumatic tire having the above-described characteristics, which is obtained by using the composition.

As a result of intensive studies to achieve the above object, the present inventors do not reduce the activity of the modified polymer when a modified polymer containing a heterofunctional group capable of generating an onium cation by an acid exists. The present inventors have found that the above object can be achieved by setting the amount of an organic acid, which is an acidic component such as stearic acid used as a vulcanization acceleration aid added at the time of blending, to a specific value or less. The present invention has been completed based on such findings.
That is, the present invention
[1] For 100 parts by mass of a rubber component consisting of 5 to 90 parts by mass of a modified polymer (A) containing a heterofunctional group capable of generating an onium cation by an acid and 95 to 10 parts by mass of another polymer component (B), A rubber composition obtained by blending 10 to 150 parts by mass of a reinforcing filler (C) and less than 1 part by mass of an organic acid (D),
[2] The rubber composition according to the above [1], wherein the component (B) is natural rubber and / or diene synthetic rubber,
[3] The rubber composition according to the above [1] or [2], wherein the hetero functional group capable of generating the onium cation is a nitrogen-containing functional group,
[4] The above-mentioned [3], wherein the nitrogen-containing functional group is at least one selected from an amino group, an imino group, a pyridyl group, a nitrile group, a hydrazine group, an amidine group, an amidrazon group, a urea group, and a thiourea group. Rubber composition,
[5] Conjugated diene synthesis wherein the modified polymer (A) is obtained by anionic polymerization of a conjugated diene compound alone or a conjugated diene compound and an aromatic vinyl compound in an organic solvent using an organic alkali metal as an initiator. A compound (H) containing in one molecule a functional group (F) capable of forming an onium cation and a functional group (F) capable of forming a bond with the active anion site of the polymer intermediate is reacted with the active end of the rubber. The rubber composition according to any one of the above [1] to [4],
[6] The modified polymer (A) is obtained by anionic polymerization of a conjugated diene compound alone or a conjugated diene compound and an aromatic vinyl compound in an organic solvent using a nitrogen-containing organic alkali metal (I) as an initiator. The rubber composition according to any one of the above [1] to [4],
[7] The modified polymer compound (A) includes a conjugated diene compound and / or a modified monomer compound (K) containing a polymerizable functional group (J) and a functional group (G) capable of generating an onium cation in one molecule. A rubber composition according to any one of the above [1] to [4] obtained by copolymerizing with an aromatic vinyl compound;
[8] The rubber composition according to any one of the above [5] to [7], wherein the conjugated diene compound is 1,3-butadiene and / or isoprene,
[9] The rubber composition according to any one of the above [5] to [7], wherein the aromatic vinyl compound is styrene,
[10] The functional group (F) is a functional group represented by C═X (X is a kind selected from a carbon atom, a nitrogen atom, and a sulfur atom), or SiR _n Y ₍₃ − _n) (R is When it is a C1-C18 hydrocarbyl group, and a plurality of Rs are present, they may be the same or different from each other, Y is a halogen group or a C1-C18 hydrocarbyloxy group, and a plurality of Ys are present Are the same or different from each other), and the rubber composition according to the above [5],
[11] The functional group (G) is a protected primary amino group, protected secondary amino group, tertiary amino group, imino group, ketimine group, aldimino group, pyridyl group, nitrile group, isocyanate group, The rubber composition according to the above item [5], which is at least one selected from a hydrazine group, an amidine group, an amidrazone group, a urea group, and a thiourea group;
[12] The rubber composition according to [5], wherein the compound (H) is a monomolecular compound in which the functional groups (F) and (G) are linked by a divalent hydrocarbyloxy group having 1 to 20 carbon atoms. ,
[13] The rubber composition according to the above [6], wherein the compound (I) is a compound represented by the following general formula (1) or (2):

Wherein R ¹ and R ² are selected from the group consisting of alkyl, cycloalkyl or aralkyl having 1 to 12 carbon atoms, and may be the same or different, and R ³ is a methylene group of 3 to 12 A kind selected from the group consisting of alkylene, oxy- or amino-alkylene groups having
[14] The rubber composition according to the above [7], wherein the polymerizable functional group (J) is a conjugated diene group or an aromatic vinyl group.
[15] The rubber composition according to any one of [1] to [14], wherein the organic acid of the component (D) includes at least one selected from fatty acids, resin acids, coal acids, and rosin acids.
[16] The inorganic filler of component (C) is carbon black, silica, and general formula (3)
nM · xSiO _y · zH ₂ O (3)
[Wherein, M is at least selected from metals selected from aluminum, magnesium, titanium, calcium and zirconium, oxides or hydroxides of these metals, hydrates thereof, and carbonates of the metals. N, x, y, and z are each an integer of 1 to 5, an integer of 0 to 10, an integer of 2 to 5, and an integer of 0 to 10. ]
The rubber composition according to the above [1] to [15], which is at least one selected from inorganic fillers represented by:
[17] The rubber composition according to [16], wherein (C) the filler contains silica and / or carbon black,
[18] A compounding agent selected from sulfur, a vulcanization accelerator, a softening agent, a scorch inhibitor, an anti-aging agent, a tackifier, a foaming agent, a foaming aid, and a resin other than the component (D). A rubber composition according to any one of the above [1] to [17],
[19] A pneumatic tire using the rubber composition according to any one of [1] to [18] as a tire member, and [20] a tire member comprising a tread, a base tread, a sidewall, and a side reinforcement. The pneumatic tire according to [19], which is any one of rubber and bead filler,
Is to provide.

According to the present invention, in the presence of a modified polymer containing a heterofunctional group capable of generating an onium cation by an acid, the total amount of acidic components of an organic acid such as stearic acid added at the time of compounding is 100 parts by mass of the rubber component. By making the amount less than 1 part by mass, the low heat buildup and wear resistance of the rubber composition and the pneumatic tire using the rubber composition can be improved.
That is, by suppressing the acidic component, the number of modified groups that are onium cationized by the acidic component is reduced, so that the activity of the existing modified group is not impaired, and is used for the interaction with the filler, Low exothermic wear resistance can be improved.

First, the rubber composition of the present invention will be described.
[Rubber composition]
The rubber composition of the present invention is 100 parts by mass of a rubber component composed of 5 to 90 parts by mass of a modified polymer (A) containing a heterofunctional group capable of generating an onium cation by an acid and 95 to 10 parts by mass of another polymer component (B). It is characterized by being obtained by blending 10 to 150 parts by mass of the reinforcing filler (C) and less than 1 part by mass of the organic acid (D) with respect to the parts.

<(A) Modified polymer containing hetero functional group capable of generating onium cation by acid>
The onium cation is a compound containing an element having a lone pair such as oxygen, sulfur, nitrogen, etc., which are heteroatoms, and a proton or other cationic reagent is coordinated to these lone electrons. Refers to the resulting compound. Among them, the heterofunctional group capable of generating an onium cation is particularly preferably a nitrogen-containing functional group. For example, amino group, imino group, pyridyl group, nitrile group, hydrazine group, amidine group amidolazone group, urea group and the like can be mentioned.

[Synthesis of Conjugated Diene (Co) polymer]
In the composition of the present invention, the modified polymer (A) containing a heterofunctional group capable of generating an onium cation by an acid is initiated with an organic alkali metal, and a conjugated diene compound (monomer) alone or an aromatic vinyl in an organic solvent. A functional group (F) that forms a bond with an active anion site of a polymer intermediate as a modifier at the active terminal of a conjugated diene (co) polymer obtained by anionic polymerization of a compound (monomer) in an organic solvent. ) And a compound (H) containing in one molecule a functional group (G) capable of generating an onium cation.

  The active site metal present in the molecule of the conjugated diene (co) polymer is preferably one selected from alkali metals and alkaline earth metals, preferably alkali metals, and particularly preferably lithium metal.

  The modified polymer (A) is obtained by anionic polymerization of a conjugated diene compound alone or a conjugated diene compound and an aromatic vinyl compound in an organic solvent using a nitrogen-containing organic alkali metal (I) as an initiator. it can.

<Example of monomer>
Examples of the conjugated diene group include 1,3-butadiene group, isoprene group, 1,3-pentadiene group, 2,3-dimethyl-1,3-butadiene group, 2-phenyl-1,3-butadiene group, 1 , 3-hexadiene group and the like. These may be used singly or in combination of two or more, among which 1,3-butadiene group, isoprene group and 2,3-dimethyl-1,3-butadiene group are particularly preferable. .
Examples of the aromatic vinyl group used for copolymerization with these conjugated diene groups include styrene group, α-methylstyrene group, 1-vinylnaphthalene group, 3-vinyltoluene group, ethylvinylbenzene group, and divinylbenzene. Group, 4-cyclohexylstyrene group, 2,4,6-trimethylstyrene group and the like. These may be used alone or in combination of two or more, and among them, a styrene group is particularly preferable.

  Furthermore, when copolymerization is carried out using a conjugated diene compound and an aromatic vinyl compound as monomers, the use of 1,3-butadiene and styrene, respectively, is practical, such as the availability of the monomers, and The anionic polymerization characteristics are particularly suitable because of excellent living characteristics.

<Modified polymer containing a modified monomer compound (K) containing a polymerizable functional group (J) and a functional group (G) capable of generating an onium cation in one molecule>
The modified polymer (A) is a modified monomer compound (K) containing a polymerizable functional group (J) and a functional group (G) capable of generating an onium cation in one molecule, a conjugated diene compound and / or an aromatic. It can be obtained by copolymerizing with a vinyl compound.
The polymerization method is not limited as long as the modified monomer compound (K) and the conjugated diene and / or aromatic vinyl compound are copolymerized, and the target polymer can be produced by anionic polymerization, emulsion polymerization, or the like.
The functional group (G) used in this modified monomer (K) is a protected primary amino group, protected secondary amino group, tertiary amino group, imino group, ketimine group, aldimino group, pyridyl group, nitrile. Group, isocyanate group, hydrazine group, amidine group, amidrazon group, urea group, thiourea group and the like.
Representative modified monomer compounds (K) include protected 4-vinylaniline (primary amine), protected anilinostyrene (secondary amine), and the like.
Examples of the vinyl monomer having a pyridyl group include 2-vinylpyridine, 3-vinylpyridine, 4-vinylpyridine, 5-methyl-2-vinylpyridine, 5-ethyl 2-vinylpyridine, and the like. In particular, 2-vinylpyridine, 4-vinylpyridine and the like are preferable.

<Polymerization initiator>
The lithium compound of the polymerization initiator is not particularly limited, but hydrocarbyl lithium and the lithium amide compound which is the aforementioned nitrogen-containing organic alkali metal (I) are preferably used. When the former hydrocarbyl lithium is used, the polymerization starts. A conjugated diene polymer having a hydrocarbyl group at the terminal and the other terminal being a polymerization active site is obtained. When the latter lithium amide compound is used, a conjugated diene polymer having a nitrogen-containing group at the polymerization initiation terminal and the other terminal being a polymerization active site is obtained.

  As the hydrocarbyl lithium, those having a hydrocarbyl group having 2 to 20 carbon atoms are preferable, for example, ethyl lithium, n-propyl lithium, isopropyl lithium, n-butyl lithium, sec-butyl lithium, tert-octyl lithium, n-decyl. Examples include lithium, phenyllithium, 2-naphthyllithium, 2-butyl-phenyllithium, 4-phenyl-butyllithium, cyclohexyllithium, cyclobenthyllithium, and reactive organisms of diisopropenylbenzene and butyllithium. Of these, n-butyllithium is particularly preferred.

<Nitrogen-containing organic alkali metal (I)>
On the other hand, as a lithium amide compound containing a nitrogen atom, the following general formula (1),

[Wherein R ¹ and R ² are selected from the group consisting of alkyl having 1 to 12 carbon atoms, cycloalkyl or aralkyl, and may be the same or different. Li represents lithium. Or general formula (2)

[Wherein R ³ is selected from the group consisting of alkylene, oxy- or amino-alkylene groups having 3 to 12 methylene groups. Li represents lithium. ]
Examples of the lithium amide compound containing a nitrogen atom represented by the general formula (1) or (2) include lithium hexamethylene imide, lithium pyrrolidide, lithium piperide, lithium heptamethylene imide, lithium dodecamethylene imide, lithium Dimethylamide, lithium diethylamide, lithium dibutylamide, lithium dipropylamide, lithium diheptylamide, lithium dihexylamide, lithium dioctylamide, lithium di-2-ethylhexylamide, lithium didecylamide, lithium-N-methylpiverazide, lithium ethylpropylamide Lithium ethyl butyramide, lithium ethyl benzylamide, lithium methylphenethyl amide and the like. Among these, in view of the interaction effect on carbon black and the ability to initiate polymerization, cyclic lithium amides such as lithium hexamethylene imide, lithium pyrrolidide, lithium piperide, lithium heptamethylene imide, and lithium dodecamethylene imide are preferable, In particular, lithium hexamethylene imide and lithium pyrrolidide are suitable.

  In general, these lithium amide compounds prepared from secondary amines and lithium compounds can be used for polymerization, but can also be prepared in the polymerization system (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.

There is no restriction | limiting in particular as a method of manufacturing a conjugated diene polymer by anionic polymerization using the said lithium compound as a polymerization initiator, A conventionally well-known method can be used.
Specifically, in an organic solvent inert to the reaction, for example, a hydrocarbon solvent such as an aliphatic, alicyclic or aromatic hydrocarbon compound, the conjugated diene compound or the conjugated diene compound and the aromatic vinyl compound are The desired conjugated diene polymer can be obtained by anionic polymerization in the presence of the randomizer used, if desired, using a lithium compound as a polymerization initiator.

  The hydrocarbon solvent is preferably one having 3 to 8 carbon atoms, such as 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.

<Randomizer>
The randomizer used as desired is a control of the microstructure of the conjugated diene polymer, 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, or the like. It is a compound having an action of controlling the composition distribution of monomer units in a conjugated diene compound-aromatic vinyl compound copolymer, for example, randomizing butadiene units and styrene units in a butadiene-styrene copolymer. The randomizer is not particularly limited, and 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 ′, Examples thereof include ethers such as N′-tetramethylethylenediamine and 1,2-dipiperidinoethane, and tertiary amines. Further, potassium salts such as potassium tert-amylate and potassium tert-butoxide, and sodium salts such as sodium tert-amylate can also be used.

  These randomizers may be used individually by 1 type, and may be used in combination of 2 or more type. The amount used is preferably selected in the range of 0.01 to 1000 molar equivalents per mole of the 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.

In this polymerization, it is desirable that all raw materials involved in the polymerization, such as a polymerization initiator, a solvent, and a monomer, are obtained by removing reaction inhibitors such as water, oxygen, carbon dioxide, and protic compounds.
It is preferable that the glass transition temperature (Tg) calculated | required by the differential thermal analysis method of the conjugated diene type polymer obtained is -95 degreeC--15 degreeC. By setting the glass transition temperature within the above range, it is possible to obtain a conjugated diene polymer that can suppress the increase in viscosity and can be easily handled.

[Modifier]
<Functional group (F) which forms bond with active anion site of polymerized polymer intermediate>
The functional group (F) is C = X [wherein X is a kind selected from a carbon atom, a nitrogen atom and a sulfur atom. Functional groups represented by, or _{SiR n Y (3 - n)} [R is a hydrocarbyl group having 2 to 18 carbon atoms, when R there is a plurality may be the same or different, Y is a halogen radical Or it is a C1-C18 hydrocarbyl oxy group, and when two or more Y exists, they may mutually be same or different. ] Is a functional group represented by
Examples of C = X modifiers include 4-diethylaminobenzophenone, 4,4-bis (diethylamino) benzophenone, 1,3-dimethyl-2-imidazoline, 1,3-dimethyl-2-imidazoline-2-thione 1-methylpyrrolidone, 1-methylpyrrolidone-2-thione, 1-methylsilylpyrrolidone, methylenebis (1,4-phenylene) diisocyanate, hexamethylene diisocyanate and the like. Moreover, the compound which replaced the methyl of the said compound, ethyl, etc. with the other alkyl group can also be used.

In the functional group represented by SiR _n Y _(a − _n) , R is a hydrocarbyl group having 1 to 18 carbon atoms, Y is a halogen group or a hydrocarbyloxy group having 1 to 18 carbon atoms, halogen, Examples thereof include an alkoxy group having 1 to 18 carbon atoms, or an alkenyloxy group, an aryloxy group having 6 to 18 carbon atoms, an aralkyloxy group having 7 to 18 carbon atoms, etc. Among these, from the viewpoint of having good reactivity, A C1-C10 alkoxy group is preferable. The alkyl group constituting the alkoxy group may be linear, branched or cyclic. Examples of such alkoxy groups include ethoxy group, n-propoxy group, isopropoxy group, n-butoxy group, isobutoxy group, sec-butoxy group, tert-butoxy group, various pentoxy groups, various hexoxy groups, and various heptoxy groups. , Various octoxy groups, various decyloxy groups, cyclopetyloxy groups, cyclohexyloxy groups and the like. Among these, alkoxy groups having 1 to 6 carbon atoms are preferable from the viewpoint of reactivity.

  Examples of the hydrocarbyl group having 1 to 18 carbon atoms represented by R include an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aryl group having 6 to 18 carbon atoms, and 7 to 18 carbon atoms. Among these, an aralkyl group is exemplified, and among these, from the viewpoint of the reactivity and performance of the modifier, an alkyl group having 1 to 18 carbon atoms is preferable, and an alkyl group having 1 to 10 carbon atoms is more preferable. The alkyl 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 group, tert. -A butyl group, various pentyl groups, various hexyl groups, various octyl groups, various decyl groups, a cyclopentyl group, a cyclohexyl group, etc. can be mentioned. Among these, from the viewpoint of the reactivity and performance of the modifier, an alkyl group having 1 to 6 carbon atoms is preferable, and a methyl group is particularly preferable.

<Functional group (G) capable of generating onium cation>
As described above, the functional group (G) capable of generating an onium cation is preferably a nitrogen-containing functional group. Nitrogen-containing functional group (G) includes protected primary amino group, protected secondary amino group, tertiary amino group, imino group, ketimino group, aldimino group, pyridyl group, nitrile group, isocyanate group, hydrazine group , Amidine group, amidazone group, urea group, thiourea and the like.

Examples of the saturated cyclic tertiary amine compound residue in the functional group (G) include a hexamethyleneimino group, a pyrrolidinyl group, a piperidinyl group, a heptamethyleneimino group, and a dodecamethyleneimino group. Examples of the cyclic tertiary amine compound residue include an imidazole residue, a dihydroimidazole residue, an oxazole residue, and a pyridyl group.
From the viewpoint of performance, the functional group (G) includes an aldimine group, a ketimine residue, a saturated cyclic tertiary amine compound residue, an imidazole residue, a dihydroimidazole residue, a pyridyl group, a nitrile group, an isocyanate group, and a desorbing group. Preferably, it is a monovalent group having at least one nitrogen-containing functional group selected from amino groups having a separable functional group, saturated cyclic tertiary amine compound residue, ketimine residue, imidazole residue More preferably, it is a monovalent group having at least one selected from a primary amino group having a dihydroimidazole residue, a detachable functional group, and a secondary amino group.
Among the functional groups in the monovalent group represented by the functional group (G), examples of the protected primary amino group that can be deprotected include N, N-bis (trimethylsilyl) amino group, 2,2, Examples of the 5,5 tetramethyl-1-aza-2,5-disilacyclopentane group and the secondary amino group include N- (trimethylsilyl) amino group.

The modifier used in the present invention generates a functional group (F) and an onium cation that form a bond with the active anion site of the polymer intermediate at the active end of the conjugated diene synthetic rubber obtained by anionic polymerization. The compound (H) containing the functional group (G) to be obtained in one molecule is reacted. The functional groups (F) and (G) may be a monomolecular compound (H) linked by a divalent hydrocarbyl group having 1 to 20 carbon atoms, or (F) = (G). It also includes the case of (F) → (G) by bonding with a polymer.
The divalent hydrocarbyl group having 1 to 20 carbon atoms is preferably an alkanediyl group having 1 to 20 carbon atoms, more preferably an alkanediyl group having 2 to 10 carbon atoms, from the viewpoint of the performance of the modifier. More preferred are alkanediyl groups of ˜6.

<Compound (H) in which functional groups (F) and (G) are linked by a divalent hydrocarbyl group>
The above compound (H) is, for example, trialkylsilyl group in which a protecting group of the functional group (G) having a protecting group represented by -SiR ^a R ^b R ^c (wherein, R ^a, R ^b, and R ^c are A hydrocarbyloxysilane compound having a protected primary amino group, each of which is independently an alkyl group having 1 to 12 carbon atoms, preferably a methyl group, an ethyl group, a propyl group, a propyl group or a butyl group. Can be mentioned. In the case of having this protected primary amino group, as specific examples, N, N-bis (trimethylsilyl) aminopropylmethyldimethoxysilane, 1-trimethylsilyl-2,2-dimethoxy-1-aza-2-silacyclopentane, N , N-bis (trimethylsilyl) aminopropyltrimethoxysilane, N, N-bis (trimethylsilyl) aminopropyltriethoxysilane, N, N-bis (trimethylsilyl) aminopropylmethyldiethoxysilane, N, N-bis (trimethylsilyl) Aminoethyltrimethoxysilane, N, N-bis (trimethylsilyl) aminoethyltriethoxysilane, N, N-bis (trimethylsilyl) aminoethylmethyldimethoxysilane, N, N-bis (trimethylsilyl) aminoethylmethyldiethoxysilane, etc. Preferably, N, N-bis (trimethylsilyl) aminopropylmethyldimethoxysilane, N, N-bis (trimethylsilyl) aminopropylmethyldiethoxysilane or 1-trimethylsilyl-2,2-dimethoxy-1- Aza-2-silacyclopentane.
N, N-bis (trimethylsilyl) aminopropyl (methyl) methoxychlorosilane, N, N-bis (trimethylsilyl) aminopropyl (methyl) ethoxychlorosilane, N, N-bis (trimethylsilyl) aminoethyl (methyl) methoxychlorosilane, Bifunctional alkoxychlorosilane compounds such as N, N-bis (trimethylsilyl) aminoethyl (methyl) ethoxychlorosilane; N, N-bis (trimethylsilyl) aminopropyl (methyl) dichlorosilane, N, N-bis (trimethylsilyl) aminopropyl ( Bifunctional chlorosilane compounds such as methyl) dichlorosilane, N, N-bis (trimethylsilyl) aminoethyl (methyl) dichlorosilane, N, N-bis (trimethylsilyl) aminoethyl (methyl) dichlorosilane It can be mentioned.

In addition, the compound (H) includes, for example, a protected secondary amino group in which the protective group of the functional group (G) having a protective group has one trialkylsilyl group represented by -SiR ^a R ^b R ^c. And hydrocarbyloxysilane compounds having a group. Specific examples of the hydrocarbyloxysilane compound having a protected secondary amino group include N-methyl-N-trimethylsilylaminopropyl (methyl) dimethoxysilane and N-methyl-N-trimethylsilylaminopropyl (methyl) diethoxysilane. N-trimethylsilyl (hexamethyleneimin-2-yl) propyl (methyl) dimethoxysilane, N-trimethylsilyl (hexamethyleneimine-2-yl) propyl (methyl) diethoxysilane, N-trimethylsilyl (pyrrolidin-2-yl) Propyl (methyl) dimethoxysilane, N-trimethylsilyl (pyrrolidin-2-yl) propyl (methyl) diethoxysilane, N-trimethylsilyl (piperidin-2-yl) propyl (methyl) dimethoxysilane, N-trimethyl Ril (piperidin-2-yl) propyl (methyl) diethoxysilane, N-trimethylsilyl (imidazol-2-yl) propyl (methyl) dimethoxysilane, N-trimethylsilyl (imidazol-2-yl) propyl (methyl) diethoxysilane N-trimethylsilyl (4,5-dihydroimidazol-5-yl) propyl (methyl) dimethoxysilane, N-trimethylsilyl (4,5-dihydroimidazol-5-yl) propyl (methyl) diethoxysilane, and the like. Of these, N-methyl-N-trimethylsilylaminopropyl (methyl) dimethoxysilane and N-methyl-N-trimethylsilylaminopropyl (methyl) diethoxysilane are preferable.
N-methyl-N-trimethylsilylaminopropyl (methyl) methoxychlorosilane, N-methyl-N-trimethylsilylaminopropyl (methyl) ethoxychlorosilane, N-trimethylsilyl (hexamethyleneimin-2-yl) propyl (methyl) methoxychlorosilane N-trimethylsilyl (hexamethyleneimin-2-yl) propyl (methyl) ethoxychlorosilane, N-trimethylsilyl (pyrrolidin-2-yl) propyl (methyl) methoxychlorosilane, N-trimethylsilyl (pyrrolidin-2-yl) propyl (methyl) ) Ethoxychlorosilane, N-trimethylsilyl (piperidin-2-yl) propyl (methyl) methoxychlorosilane, N-trimethylsilyl (piperidin-2-yl) propyl (methyl) Xylchlorosilane, N-trimethylsilyl (imidazol-2-yl) propyl (methyl) methoxychlorosilane, N-trimethylsilyl (imidazol-2-yl) propyl (methyl) ethoxychlorosilane, N-trimethylsilyl (4,5-dihydroimidazole-5 And chlorosilane compounds such as yl) propyl (methyl) methoxychlorosilane and N-trimethylsilyl (4,5-dihydroimidazol-5-yl) propyl (methyl) ethoxychlorosilane.

Furthermore, when the functional group (G) has a ketimine residue, for example, the compound (H) includes N- (1,3-dimethylbutylidene) -3- [diethoxy (methyl) silyl]- 1-propanamine, N- (1-methylethylidene) -3- [diethoxy (methyl) silyl] -1-propanamine, N-ethylidene-3- [diethoxy (methyl) silyl] -1-propanamine, N- [1-Methylpropylidene) -3- [diethoxy (methyl) silyl] -1-propanamine, N- (4-N, N-dimethylaminobenzylidene) -3- [diethoxy (methyl) silyl] -1-propane Amines, N- (cyclohexylidene) -3- [diethoxy (methyl) silyl] -1-propanamine and the corresponding diethyl ethers to these diethoxy (methyl) silyl compounds Ci (ethyl) silyl compound, dipropoxy (methyl) silyl compound, dipropoxy (ethyl) silyl compound and the like can be mentioned. Among these, N- (1,3-dimethylbutylidene)-[diethoxy (methyl) silyl ] -Propanamine and N- (1,3-dimethylbutylidene)-[dipropoxy (methyl) silyl] -1-propanamine are preferred.
N- (1,3-dimethylbutylidene) -3- [ethoxy (methyl) chlorosilyl] -1-propanamine, N- (1-methylethylidene) -3- [ethoxy (methyl) chlorosilyl] -1- Propanamine, N-ethylidene-3- [ethoxy (methyl) chlorosilyl] -1-propanamine, N- [1-methylpropylidene) -3- [ethoxy (methyl) chlorosilyl] -1-propanamine, N- ( 4-N, N-dimethylaminobenzylidene) -3- [ethoxy (methyl) chlorosilyl] -1-propanamine, N- (cyclohexylidene) -3- [ethoxy (methyl) chlorosilyl] -1-propanamine and these Ethoxy (ethyl) chlorosilyl compounds corresponding to ethoxy (methyl) chlorosilyl compounds, propoxy (methyl) chloro A silyl compound, a propoxy (ethyl) chlorosilyl compound, etc. can be mentioned.

In addition, when the functional group (G) has an imidazole residue or a dihydroimidazole residue, for example, the compound (H) includes 1- [3- [diethoxy (methyl) silyl] propyl] -imidazole, -[3- [diethoxy (ethyl) silyl] propyl] -imidazole, 1- [3- [dipropoxy (methyl) silyl] propyl] -imidazole, 1- [3- [dipropoxy (ethyl) silyl] propyl] -imidazole, 1- [3- [diethoxy (methyl) silyl] propyl] -4,5-dihydroimidazole, 1- [3- [diethoxy (ethyl) silyl] propyl] -4,5-dihydroimidazole, 1- [3- [ Dipropoxy (methyl) silyl] propyl] -4,5-dihydroimidazole, 1- [3- [dipropoxy (ethyl) Silyl] propyl] -4,5-dihydroimidazole and the like, among which 1- [3- [diethoxy (methyl) silyl] propyl] -imidazole, 1- [3- [dipropoxy (methyl)] Silyl] propyl] -imidazole, 1- [3- [diethoxy (methyl) silyl] propyl] -4,5-dihydroimidazole and 1- [3- [dipropoxy (methyl) silyl] propyl] -4,5-dihydroimidazole Is preferred.
Also, 1- [3- [ethoxy (methyl) chlorosilyl] propyl] -imidazole, 1- [3- [ethoxy (ethyl) chlorosilyl] propyl] -imidazole, 1- [3- [propoxy (methyl) chlorosilyl] propyl] -Imidazole, 1- [3- [propoxy (ethyl) chlorosilyl] propyl] -imidazole, 1- [3- [ethoxy (methyl) chlorosilyl] propyl] -4,5-dihydroimidazole, 1- [3- [ethoxy ( Ethyl) chlorosilyl] propyl] -4,5-dihydroimidazole, 1- [3- [propoxy (methyl) chlorosilyl] propyl] -4,5-dihydroimidazole, 1- [3- [propoxy (ethyl) chlorosilyl] propyl] Examples include -4,5-dihydroimidazole.

In addition, when the functional group (G) has a pyridyl group or a nitrile group, for example, the compound (H) includes 2- [2- [diethoxy (methyl) silyl] ethyl] -pyridine, 2- [ 2- [dipropoxy (methyl) silyl] ethyl] -pyridine, 2- [3- [diethoxy (methyl) silyl] propyl] -pyridine, 2- [3- [diethoxy (ethyl) silyl] propyl] -pyridine, 2- [3- [dipropoxy (methyl) silyl] propyl] -pyridine, 2- [3- [dipropoxy (ethyl) silyl] propyl] -pyridine, 4- [2- [diethoxy (methyl) silyl] ethyl] -pyridine, 4 -[2- [dipropoxy (methyl) silyl] ethyl] -pyridine, 4- [3- [diethoxy (methyl) silyl] propyl] -pyridine, 4- [3 Pyridine compounds such as [diethoxy (ethyl) silyl] propyl] -pyridine, 4- [3- [dipropoxy (methyl) silyl] propyl] -pyridine, 4- [3- [dipropoxy (ethyl) silyl] propyl] -pyridine, 1-cyano-3- [diethoxy (methyl) silyl] -propane, 1-cyano-3- [diethoxy (ethyl) silyl] -propane, 1-cyano-3- [dipropoxy (methyl) silyl] -propane, 1- And cyano compounds such as cyano-3- [dipropoxy (ethyl) silyl] -propane. Among these, 2- [3- [diethoxy (methyl) silyl] propyl] -pyridine, 2- [3- [dipropoxy (methyl) silyl] propyl] -pyridine, 4- [3- [diethoxy (methyl) silyl ] Propyl] -pyridine, 4- [3- [dipropoxy (methyl) silyl] propyl] -pyridine, 1-cyano-3- [diethoxy (methyl) silyl] -propane and 1-cyano-3- [dipropoxy (methyl) Silyl] -propane is preferred.
Also, 2- [2- [ethoxy (methyl) chlorosilyl] ethyl] -pyridine, 2- [2- [propoxy (methyl) chlorosilyl] ethyl] -pyridine, 2- [3- [ethoxy (methyl) chlorosilyl] propyl] -Pyridine, 2- [3- [ethoxy (ethyl) chlorosilyl] propyl] -pyridine, 2- [3- [propoxy (methyl) chlorosilyl] propyl] -pyridine, 2- [3- [propoxy (ethyl) chlorosilyl] propyl ] -Pyridine, 4- [2- [ethoxy (methyl) chlorosilyl] ethyl] -pyridine, 4- [2- [propoxy (methyl) chlorosilyl] ethyl] -pyridine, 4- [3- [ethoxy (methyl) chlorosilyl] Propyl] -pyridine, 4- [3- [ethoxy (ethyl) chlorosilyl] propyl] -pyridine, -[3- [propoxy (methyl) chlorosilyl] propyl] -pyridine, pyridine compounds such as 4- [3- [propoxy (ethyl) chlorosilyl] propyl] -pyridine, 1-cyano-3- [ethoxy (methyl) chlorosilyl] -Propane, 1-cyano-3- [ethoxy (ethyl) chlorosilyl] -propane, 1-cyano-3- [propoxy (methyl) chlorosilyl] -propane, 1-cyano-3- [propoxy (ethyl) chlorosilyl] -propane And cyano compounds.

In addition, when the functional group (G) has a (thio) isocyanate group or an oxazole residue, for example, the compound (H) includes 1-isocyanate 3- [diethoxy (methyl) silyl] -propane, Isocyanates such as 1-isocyanate 3- [diethoxy (ethyl) silyl] -propane, 1-isocyanate 3- [dipropoxy (methyl) silyl] -propane, 1-isocyanate 3- [dipropoxy (ethyl) silyl] -propane Nert compound, thioisocyanate compound in which isocyanate in the above isocyanate compound is replaced with thioisocyanate, 4- [3- [diethoxy (methyl) silyl] propyl] -oxazole, 4- [3- [diethoxy (ethyl) silyl ] Propyl] -oxazole, 4- [3- [dipropoxy ( Chill) silyl] propyl] - oxazole, 4- [3- [dipropoxy (ethyl) silyl] propyl] - such as oxazole compounds such as oxazole and the like. Among these, 1-isocyanate 3- [diethoxy (methyl) silyl] -propane, 1-isocyanate 3- [dipropoxy (methyl) silyl] -propane, 4- [3- [diethoxy (methyl) silyl] propyl ] -Oxazole and 4- [3- [dipropoxy (methyl) silyl] propyl] -oxazole are preferred.
In the present invention, the oxazole residue also includes an isoxazole residue.
Also, 1-isocyanate 3- [ethoxy (methyl) chlorosilyl] -propane, 1-isocyanate 3- [ethoxy (ethyl) chlorosilyl] -propane, 1-isocyanate 3- [propoxy (methyl) chlorosilyl] -propane, Isocyanate compounds such as 1-isocyanate 3- [propoxy (ethyl) chlorosilyl] -propane, thioisocyanate compounds in which the isocyanate in the isocyanate compound is replaced with thioisocyanate, 4- [3- [ethoxy (methyl)] Chlorosilyl] propyl] -oxazole, 4- [3- [ethoxy (ethyl) chlorosilyl] propyl] -oxazole, 4- [3- [propoxy (methyl) chlorosilyl] propyl] -oxazole, 4- [3- [propoxy (ethyl) ) Chlorosiri ] Propyl] - such as oxazole compounds such as oxazole and the like.

In addition, the amino group derived from the modifying agent of the modified conjugated diene polymer used in the present invention is suitable in any case, whether it is protected or deprotected and converted to a primary amine or a secondary amine. is there. If a deprotection process is performed, the following procedure is used.
That is, the silyl protecting group on the protected amino group is converted to a free amino group by hydrolysis. By removing the solvent from this, a dried polymer having a primary amino group or a secondary amino group is obtained.
The amount of water used in this hydrolysis reaction is preferably a molar amount that is excessive, 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.

<Modified conjugated diene-based (co) polymer (A)>
The modified conjugated diene-based (co) polymer (A) thus obtained has a Mooney viscosity (ML _{1 + 4} , 100 ° C.) of preferably 10 to 150, more preferably _{15 to} 100. When the Mooney viscosity is less than 10, sufficient rubber properties such as fracture resistance are not obtained, and when it exceeds 150, workability is poor and it is difficult to knead with the compounding agent.
The Mooney-viscosity (ML _{1 + 4} , 130 ° C.) of the unvulcanized rubber composition according to the present invention containing the modified conjugated diene (co) polymer is preferably 10 to 150, more preferably 30 to 30. 100.
The modified conjugated diene-based (co) polymer used in the rubber composition according to the present invention has a ratio (Mw / Mn) of weight average molecular weight (Mw) to number average molecular weight (Mn), that is, molecular weight distribution (Mw / Mn). Is preferably 1 to 8, and more preferably 1.1 to 5.
Moreover, when molecular weight distribution is controllable by terminal coupling etc., Preferably it is 1-5, More preferably, it is 1-3.5, More preferably, it is 1.5-3.0.
Even if the modified conjugated diene (co) polymer is blended with the rubber composition by making the molecular weight distribution (Mw / Mn) of the modified conjugated diene (co) polymer within the above range, the workability of the rubber composition is improved. It is not lowered, kneading is easy, and the physical properties of the rubber composition can be sufficiently improved.

The modified conjugated diene-based (co) polymer used in the rubber composition according to the present invention preferably has a number average molecular weight (Mn) of 100,000 to 800,000, more preferably 120,000 to 500,000, more preferably 150,000 to 300,000. By setting the number average molecular weight of the modified conjugated diene-based (co) polymer within the above range, the elastic modulus of the vulcanizate is reduced and an increase in hysteresis loss is suppressed to obtain excellent fracture resistance, and the modified conjugated diene-based polymer Excellent kneading workability of a rubber composition containing a synthetic rubber can be obtained.
The modified conjugated diene polymer used in the rubber composition according to the present invention may be used singly or in combination of two or more.

<Other rubber components (B)>
In the present invention, the rubber component is a modified conjugated diene-based synthetic rubber of 5 to 90 mass of the above-mentioned component (A), and the other rubber component is a natural rubber and / or diene-based synthetic rubber of 95 to 10 as the component (B). It is comprised from the mass%.
Examples of the rubber component used in combination with the modified conjugated diene-based synthetic rubber of the component (A) include natural rubber and other diene-based synthetic rubbers. Examples of other diene-based synthetic rubbers include styrene-butadiene copolymers. (SBR), polybutadiene (BR), polyisoprene (IR), styrene-isoprene copolymer (SIR), butyl rubber (IIR), halogenated butyl rubber, ethylene-propylene-diene terpolymer (EPDM) and these A mixture is mentioned.
Of these, natural rubber, styrene-butadiene copolymer (SBR), polybutadiene (BR), and polyisoprene (IR) are preferable.

<Inorganic filler (C)>
In the rubber composition according to the present invention, it is necessary to include 10 to 150 parts by mass of the filler as the component (C) with respect to 100 parts by mass of the rubber component composed of the components (A) and (B). It is. More preferably, it is 20-120 mass parts, More preferably, it is 30-100 mass parts. By setting the amount of the inorganic filler in the above range, excellent low heat build-up and wear resistance effects can be exhibited.
Further, the rubber composition according to the present invention preferably contains silica and / or carbon black as an inorganic filler. In addition, when the compound used as a modifier of the modified conjugated diene polymer of the component (A), which is a rubber component, contains a nitrogen atom and a silicon atom in one molecule, it contains carbon black In the rubber composition, introduction of silicon atoms is preferable because heat generation can be suppressed in a rubber composition containing a reinforcing inorganic filler such as silica.

The filler is carbon black, silica and general formula (3)
nM · xSiO _y · zH ₂ O (3)
[Wherein, M is at least selected from metals selected from aluminum, magnesium, titanium, calcium and zirconium, oxides or hydroxides of these metals, hydrates thereof, and carbonates of the metals. N, x, y, and z are each an integer of 1 to 5, an integer of 0 to 10, an integer of 2 to 5, and an integer of 0 to 10. ] It is at least 1 sort (s) chosen from the inorganic fillers represented.
Here, as the carbon black, in order that the vulcanized rubber properties of the obtained rubber composition satisfy the above vulcanized rubber properties, for example, various grades of carbon black such as SAF, HAF, ISAF, FEF, GPF, etc. Can be used alone or in admixture.
Silica is not particularly limited, but wet silica, dry silica, and colloidal silica are preferable. Among these, wet silica is most preferable because it has the most remarkable effect of improving the fracture characteristics and the wet grip property. These can be used alone or in combination.

Specifically, the inorganic filler represented by the general formula (3) includes alumina (Al ₂ O ₃ ) such as γ-alumina and α-alumina, and alumina monohydrate (Al ₂ O such as boehmite and diaspore). ₃ · H ₂ O), Gibbsite, Bayerite, etc. Aluminum hydroxide [Al (OH) ₃ ], Aluminum carbonate [Al ₂ (CO ₃ ) ₂ ], Magnesium hydroxide [Mg (OH) ₂ ], Magnesium oxide ( MgO), magnesium carbonate (MgCO _3), talc _{(3MgO · 4SiO 2 · H 2} O), attapulgite _{(5MgO · 8SiO 2 · 9H 2} O), titanium white (TiO _2), titanium black (TiO _2n-1), calcium oxide (CaO), calcium hydroxide [Ca (OH) _2], magnesium aluminum oxide _{(MgO · Al 2 O 3)} , clay _{(Al 2 O 3 · 2SiO 2} ), Kao Down _{(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.), magnesium calcium silicate (CaMgSiO ₄ ), calcium carbonate (CaCO ₃ ), zirconium oxide (ZrO ₂ ), zirconium hydroxide [ZrO (OH) ₂ · nH ₂ O], carbonic acid zirconium _{[Zr (CO 3) 2]} , crystalline aluminosilicate containing hydrogen, alkali metal or alkaline earth metal which corrects a charge as various zeolites There can be used.
In addition, as the inorganic filler represented by the general formula (3), M is at least one selected from aluminum metal, aluminum oxide or hydroxide, hydrates thereof, and aluminum carbonate. Is preferred.
Of these, carbon black and silica are preferred as the filler.

<Silane coupling agent>
In the rubber composition of the present invention, when silica is used as the reinforcing filler, a silane coupling agent can be blended for the purpose of further improving the reinforcement and low heat build-up.
Examples of the silane coupling agent include bis (3-triethoxysilylpropyl) tetrasulfide, bis (3-triethoxysilylpropyl) trisulfide, bis (3-triethoxysilylpropyl) disulfide, and bis (2-sodium trisulfide). Ethoxysilylethyl) tetrasulfide, bis (3-trimethoxysilylpropyl) tetrasulfide, bis (2-trimethoxysilylethyl) tetrasulfide, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 2-mercapto Ethyltrimethoxysilane, 2-mercaptoethyltriethoxysilane, 3-trimethoxysilylpropyl-N, N-dimethylthiocarbamoyl tetrasulfide, 3-triethoxysilylpropyl-N, N-dimethylthioca Vamoyl tetrasulfide, 2-triethoxysilylethyl-N, N-dimethylthiocarbamoyl tetrasulfide, 3-trimethoxysilylpropylbenzothiazolyl tetrasulfide, 3-triethoxysilylpropylbenzothiazolyl tetrasulfide, 3- Triethoxysilylpropyl methacrylate monosulfide, 3-trimethoxysilylpropyl methacrylate monosulfide, bis (3-diethoxymethylsilylpropyl) tetrasulfide, 3-mercaptopropyldimethoxymethylsilane, dimethoxymethylsilylpropyl-N, N-dimethylthio Carbamoyl tetrasulfide, dimethoxymethylsilylpropylbenzothiazolyl tetrasulfide, and the like can be mentioned. Among these, from the viewpoint of reinforcing effect, Scan (3-triethoxysilylpropyl) polysulfide and 3-trimethoxysilylpropyl benzothiazolyl tetrasulfide are preferable.
One of these silane coupling agents may be used alone, or two or more thereof may be used in combination.

  In the rubber composition of the present invention, since a modified polymer having a functional group having high affinity for silica introduced in the molecular active site is used as the rubber component, the amount of the silane coupling agent is usually This can be reduced more than in the case of. The blending amount of the preferred silane coupling agent varies depending on the type of the silane coupling agent, but is preferably selected in the range of 1 to 20% by mass with respect to silica. If this amount is less than 1% by mass, the effect as a coupling agent is hardly exhibited, and if it exceeds 20% by mass, the rubber component may be gelled. From the viewpoint of the effect as a coupling agent and the prevention of gelation, the preferred amount of the silane coupling agent is in the range of 5 to 15% by mass.

<Organic acid (D)>
In the rubber composition concerning this invention, it is necessary to mix | blend less than 1 mass part of (D) organic acid with respect to 100 mass parts of rubber components. Although there is no restriction | limiting in particular about a lower limit, it is about 0.1 mass part.
As described above, most of the organic acids are carboxylic acids and are not particularly limited as long as they have a carboxyl group (—COOH). Examples include fatty acids (mainly stearic acid) used as vulcanization accelerators.
Vulcanization accelerators are used in combination with metal oxides (mainly zinc white) and fatty acids (mainly stearic acid) in the sulfur vulcanization system to activate the vulcanization accelerators and improve vulcanization (crosslinking) efficiency. Use to improve.

(Preparation and use of rubber composition)
In the rubber composition according to the present invention, various chemicals usually used in the rubber industry, for example, sulfur, vulcanization accelerator, softener, process oil, anti-aging, as long as the effects of the present invention are not impaired. An agent, an anti-scorch agent, zinc white, an anti-adhesive agent, a foaming agent, a foaming aid and a resin can be contained.
Further, the rubber composition of the present invention is obtained by kneading using a kneader such as an open kneader such as a roll, a closed kneader such as a Banbury mixer, and vulcanized after molding. Applicable to various rubber products. For example, it can be used for tire applications such as tire treads, under treads, carcass, sidewall side reinforcing rubber and bead fillers, but especially for low fuel consumption with excellent balance of low heat build-up, wear resistance and breaking strength It is suitably used as a tread rubber for tires, large tires, and high performance tires.

[tire]
The tire of the present invention is characterized in that the above-described sulfur crosslinkable rubber composition of the present invention is used for a tire member. As the tire member, a tread, a base tret, a sidewall, a side reinforcing rubber, and a bead filler can be preferably mentioned, and the sulfur crosslinkable rubber composition of the present invention can be used for any of these. It is preferable to use for.
A tire using the sulfur crosslinkable rubber composition of the present invention for a tread has low rolling resistance and excellent fuel efficiency, and also has excellent fracture characteristics and wear resistance. 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 microstructure of the modified styrene-butadiene rubber (modified SBR) (bound vinyl content, bound styrene content), loss tangent (tan δ) and abrasion resistance of the rubber composition after vulcanization were evaluated by the following methods.
(1) Bonded vinyl content of the conjugated diene moiety of the modified SBR (% of the total diene moiety)
Obtained by 270 MHz ¹ H-NMR. The measurement results are shown in Table 1.
(2) Bonded styrene content of modified SBR (mass% in polymer)
Obtained by 270 MHz ¹ H-NMR. The measurement results are shown in Table 1.
(3) Loss tangent (tan δ)
Using a dynamic spectrometer manufactured by Rheometrics, Inc., measurement was performed under the conditions of tensile dynamic strain of 1%, frequency of 10 Hz, and 50 ° C., and the reciprocal of tan δ of the control was expressed as an index.
In each S-SBR of each blending type, the control indicated the result when the blending amount of stearic acid was 1.5 parts by mass as 100, and the results when the blending amount of stearic acid was changed were displayed as an index. It shows that it is excellent in low exothermic property, so that the value of an index | exponent is large. The measurement results are shown in Tables 2 and -2.
(4) Abrasion resistance Using a Ramborn type abrasion tester, the amount of wear with a slip rate of 25% at room temperature was measured, and the reciprocal of the amount of wear of the control was taken as an index. In each S-SBR of each blending type, the control indicated the result when the blending amount of stearic acid was 1.5 parts by mass as 100, and the results when the blending amount of stearic acid was changed were displayed as an index. It shows that it is excellent in abrasion resistance, so that the value of an index | exponent is large. The measurement results are shown in Tables 2 and -2.

Production Comparative Example 1
Manufacture of SBR L To a 800 mL pressure-resistant glass container that has been dried and purged with nitrogen, a cyclohexane solution of 1,3-butadiene and a cyclohexane solution of styrene are added to 60 g of 1,3-butadiene and 15 g of styrene, and 2, After adding 0.29 mmol of 2-ditetrahydrofurylpropane and 0.57 mmol of n-butyllithium (BuLi), a polymerization reaction was carried out in a warm water bath at 50 ° C. for 1.5 hours. The polymerization conversion rate at this time was almost 100%.
Thereafter, 0.5 ml of a 5 mass% isopropanol solution of 2,6-di-tert-butyl-p-cresol was added to the polymerization reaction system to stop the polymerization reaction, followed by drying according to a conventional method to obtain SBR L. The bound Styrene content of the obtained SBR L and the bound vinyl content of the butadiene moiety are shown in Table 1.

Production Example 1
Production of SBR M To a 800 mL pressure-resistant glass container which has been dried and purged with nitrogen, a cyclohexane solution of 1,3-butadiene and a cyclohexane solution of styrene are added so that 60 g of 1,3-butadiene and 15 g of styrene are obtained. After adding 0.36 mmol of 2-ditetrahydrofurylpropane and 0.72 mmol of n-butyllithium (BuLi), a polymerization reaction was carried out in a warm water bath at 50 ° C. for 1.5 hours. The polymerization conversion rate at this time was almost 100%.
Next, 0.65 mmol of N, N-bis (trimethylsilyl) -3-aminopropylmethyldiethoxysilane was added to the polymerization reaction system, and a modification reaction was further performed at 50 ° C. for 30 minutes. Thereafter, 0.5 ml of a 5% by mass solution of 2,6-di-t-butyl-p-cresol in 5% by mass of isopropanol was added to the polymerization reaction system to stop the polymerization reaction, followed by drying according to a conventional method to obtain SBR M. Table 1 shows the bound styrene content of the obtained SBR M and the bound vinyl content of the butadiene moiety.

Production Examples 2-9
Production of SBR N to U In place of N, N-bis (trimethylsilyl) -3-aminopropylmethyldiethoxysilane in the production of SBR M, the modifier shown in Table 1 was used to obtain SBR.
N to U were obtained. The bound styrene content of SBR N to U and the bound vinyl content of the butadiene moiety are shown in Table 1.

Production Comparative Example 2
Production of SBR V SBR V was obtained by using (3-glycidoxypropyl) triethylsilane instead of N, N-bis (trimethylsilyl) -3-aminopropylmethyldiethoxysilane in the production of SBR M. . The bound styrene content of SBR V and the bound vinyl content of the butadiene moiety are shown in Table 1.

Production Example 10
Manufacture of SBR W Into a 800 mL pressure-resistant glass container that has been dried and purged with nitrogen, a cyclohexane solution of 1,3-butadiene and a cyclohexane solution of styrene are injected so as to be 60 g of 1,3-butadiene and 15 g of styrene. After sequentially adding 0.72 mmol of methyleneimine, 0.72 mol of n-butyllithium and 0.36 mmol of 2,2-tetrahydrofurylpropane, polymerization was carried out at 50 ° C. for 2.5 hours. The polymerization conversion was almost 100%.
Thereafter, 0.5 ml of a 5 mass% isopropanol solution of 2,6-di-t-butyl-p-cresol was added to the polymerization reaction system to stop the polymerization reaction, and the precipitate was precipitated in a small amount of hydrochloric acid and isopropanol. SBR W was obtained by drying by the method. The bound styrene content of SBR W and the bound vinyl content of the butadiene moiety are shown in Table 1.

Production Example 11
Manufacture of SBR X To an 800 mL pressure-resistant glass container that has been dried and purged with nitrogen, a cyclohexane solution of 1,3-butadiene and a cyclohexane solution of styrene are added so that 60 g of 1,3-butadiene and 15 g of styrene are obtained. After adding 0.360 mmol of 2-tetrahydrofurylpropane and 3.6 mmol of N, N-bis (trimethylsilyl) -4-vinylaniline, polymerization was carried out at 50 ° C. for 1.5 hours. The polymerization conversion at this time was almost 100%. Thereafter, 0.5 ml of a 5 mass% isopropanol solution of 2,6-di-t-butyl-p-cresol was added to the polymerization reaction system to stop the polymerization reaction, and then a small amount of polymer cement was analyzed by gas chromatography. It was confirmed that no unreacted monomer compound derived from vinylaniline was contained. SBR X was obtained by drying this remaining polymer cement according to a conventional method. The bound styrene content of SBR X and the bound vinyl content of the butadiene moiety are shown in Table 1.

Production Example 12
Production of SBR Y SBR Y was obtained by using 3.60 mmol of 4-vinylpyridine instead of N, N-bis (trimethylsilyl) -4-vinylaniline in the production of SBR X. The bound styrene content of SBR Y and the bound vinyl content of the butadiene moiety are shown in Table 1.

Examples 1-25 and Comparative Examples 1-33
Using the unmodified and modified solution-polymerized styrene butadiene rubber (S-SBR) of Production Examples 1 to 12 and Production Comparative Examples 1 to 2 described in Table 1, based on the blending compositions described in Tables 4 to 7 A rubber composition was prepared and vulcanized by a conventional method to evaluate tan δ and abrasion resistance.
The evaluation results are shown in Tables 2 and 2. In Tables 2 and 2, the blending amount of stearic acid and the No. of each blending composition are shown. And combinations of the unmodified and each modified S-SBR species. In addition, it shows in Table 1 about the modifier | denaturant kind of each S-SBR.

[note]
* 1. Modified and unmodified S-SBR: Unmodified S-SBR obtained in Production Examples 1 to 12 and Production Comparative Example 1 and unmodified S-SBR obtained in Production Comparative Example 2 were used.
* 2. BR: High cis BR [BR01], manufactured by JSR * 3. Oil: Aromatic oil, “Aromax # 3” manufactured by Fuji Kosan Co., Ltd.
* 4. Carbon black: HAF (N330), "Asahi # 70" manufactured by Asahi Carbon Co.
* 5. Silica: Trademark “Nipsil AQ” made by Tosoh Silica
* 6. Silane coupling agent: bis (3-triethoxysilylpropyl) tetrasulfide, manufactured by Degussa, trademark “Si69”
* 7. Anti-aging agent 6C: N- (1,3-dimethylbutyl) -N′-phenyl-p-phenylenediamine, “NOCRACK 6C” manufactured by Ouchi Shinsei Chemical Co., Ltd.
* 8. Vulcanization accelerator DPG: Diphenylguanidine, “Noxeller D” manufactured by Ouchi Shinsei Chemical Co., Ltd.
* 9. Vulcanization accelerator DM: Dibenzothiazyl disulfide, “Noxeller DM” manufactured by Ouchi Shinsei Chemical Industry Co., Ltd.
* 10. Vulcanization accelerator CZ: N-cyclohexyl-2-benzothiazylsulfenamide, “Noxeller CZ” manufactured by Ouchi Shinsei Chemical Industry Co., Ltd.

  It turns out that the Example of this invention is excellent in low heat generation property and abrasion resistance compared with a comparative example.

The rubber composition of the present invention is particularly excellent in the interaction between a rubber component and carbon black and / or silica, can further improve the dispersibility of these fillers, and has a low heat buildup and excellent wear resistance. Can be given.
Since the tire of the present invention has the above properties, it is suitable for various pneumatic tires such as radial tires for passenger cars, radial tires for light passenger cars, radial tires for light trucks, radial tires for trucks and buses, and tires for construction vehicles. Used.

Claims (20)

  Reinforcing filling with respect to 100 parts by mass of a rubber component composed of 5 to 90 parts by mass of a modified polymer (A) containing a heterofunctional group capable of generating an onium cation by an acid and 95 to 10 parts by mass of another polymer component (B) A rubber composition obtained by blending 10 to 150 parts by mass of a material (C) and less than 1 part by mass of an organic acid (D).   The rubber composition according to claim 1, wherein the component (B) is natural rubber and / or a diene synthetic rubber.   The rubber composition according to claim 1 or 2, wherein the hetero functional group capable of generating the onium cation is a nitrogen-containing functional group.   The rubber composition according to claim 3, wherein the nitrogen-containing functional group is at least one selected from an amino group, an imino group, a pyridyl group, a nitrile group, a hydrazine group, an amidine group, an amidrazon group, a urea group, and a thiourea group. object.   Activity of the conjugated diene synthetic rubber obtained by anionic polymerization of the conjugated diene compound alone or the conjugated diene compound and the aromatic vinyl compound in an organic solvent using the modified polymer (A) as an initiator. Claim obtained by reacting a compound (H) containing in one molecule a functional group (F) capable of forming an onium cation and a functional group (F) capable of forming a bond with the active anion site of the polymer intermediate at the terminal Item 5. The rubber composition according to any one of Items 1 to 4.   The modified polymer (A) is obtained by anionic polymerization of a conjugated diene compound alone or a conjugated diene compound and an aromatic vinyl compound in an organic solvent using a nitrogen-containing organic alkali metal (I) as an initiator. The rubber composition in any one of -4.   The modified polymer (A) is a conjugated diene compound and / or aromatic vinyl, wherein the modified monomer compound (K) contains a polymerizable functional group (J) and a functional group (G) capable of generating an onium cation in one molecule. The rubber composition according to claim 1, which is obtained by copolymerization with a compound.   The rubber composition according to any one of claims 5 to 7, wherein the conjugated diene compound is 1,3-butadiene and / or isoprene.   The rubber composition according to any one of claims 5 to 7, wherein the aromatic vinyl compound is styrene. The functional group (F) is a functional group represented by C = X (X is one selected from a carbon atom, a nitrogen atom, and a sulfur atom), or SiR _n Y ₍₃ − _n) (R is a carbon number of 1). -18 hydrocarbyl groups, which may be the same or different when a plurality of R are present, Y is a halogen group or a hydrocarbyloxy group having 2 to 8 carbon atoms, and is the same when a plurality of Y are present. The rubber composition according to claim 5, which may be different from each other.   The functional group (G) is protected protected primary amino group, protected secondary amino group, tertiary amino group, imino group, ketimine group, aldimino group, pyridyl group, nitrile group, isocyanate group, The rubber composition according to claim 5, wherein the rubber composition is at least one selected from a hydrazine group, an amidine group, an amidrazon group, a urea group, and a thiourea group.   The rubber composition according to claim 5, wherein the compound (H) is a monomolecular compound in which the functional groups (F) and (G) are linked by a divalent hydrocarbyloxy group having 1 to 20 carbon atoms. The rubber composition according to claim 6, wherein the compound (I) is a compound represented by the following general formula (1) or (2).

Wherein R ¹ is selected from the group consisting of alkyl, cycloalkyl or aralkyl having 1 to 12 carbon atoms, and may be the same or different, and R ² is an alkylene having 3 to 12 methylene groups. , A type selected from the group consisting of oxy- or amino-alkylene groups.)   The rubber composition according to claim 7, wherein the polysynthetic functional group (J) is a conjugated diene group or an aromatic vinyl group.   The rubber composition according to any one of claims 1 to 14, wherein the organic acid as the component (D) contains at least one selected from fatty acids, resin acids, coal acids, and rosin acids. The inorganic filler of component (C) is carbon black, silica, and the following general formula (3);
nM · xSiO _y · zH ₂ O (3)
[Wherein, M is at least selected from metals selected from aluminum, magnesium, titanium, calcium and zirconium, oxides or hydroxides of these metals, hydrates thereof, and carbonates of the metals. N, x, y, and z are each an integer of 1 to 5, an integer of 0 to 10, an integer of 2 to 5, and an integer of 0 to 10. ]
The rubber composition according to claim 1, which is at least one selected from inorganic fillers represented by the formula:   The rubber composition according to claim 16, wherein the filler (C) contains silica and / or carbon black.   Other than the component (D), sulfur, a vulcanization accelerator, a softener, a scorch inhibitor, an anti-aging agent, a tackifier, a foaming agent, a foaming aid, and a compounding agent selected from resins are blended. The rubber composition according to any one of claims 1 to 17.   A pneumatic tire using the rubber composition according to any one of claims 1 to 18 as a tire member.   The pneumatic tire according to claim 19, wherein the tire member is one of a tread, a base tread, a sidewall, a side reinforcing rubber, and a bead filler.