JP2013237724A - Rubber composition for tread and pneumatic tire using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide: a rubber composition for a tire tread that excels in grip performance, and has abrasion resistance; and a pneumatic tire using the same.SOLUTION: A rubber composition includes: (A) a rubber component containing (A-1) 5-50% by mass of a modified conjugated diene-based polymer that modifies an active terminal of a conjugated diene polymer in which a content of cis-1,4- bonding is at least 75% by mole by a hydrocarbyloxysilane compound, and (A-2) natural rubber and/or diene-based synthetic rubber; (B) 60-140 parts by mass of a reinforcing filler consisting of (B-1) 50-95% by mass of silica, and (B-2) 50-5% by mass of carbon black; and (C) 5-60 parts by mass of a resin, wherein the amount of (B) and (C) is based on 100 parts by mass of the rubber component. A pneumatic tire is manufactured by using the rubber composition in a tread rubber. A rosin resin, a terpene resin, a petroleum resin, a phenol resin, a coal resin, and a xylene resin or the like can be used as the resin.

Description

  The present invention relates to a rubber composition for a tire tread and a pneumatic tire using the same. More specifically, the present invention relates to a rubber composition for a tread containing a modified conjugated diene polymer having excellent grip performance and excellent wear resistance, and a tire using the same.

  In recent years, tread rubber for pneumatic tires used for high-speed driving has high dry grip performance, which is the braking and driving performance of tires on dry road surfaces, and wet grip performance, which is the braking and driving performance of tires on wet road surfaces. Performance is required. Among them, improvement of wet grip performance particularly on a wet road surface is a very important characteristic from the viewpoint of safety.

  In order to improve grip performance, the rubber composition is often blended with process oil and other oils. However, if the amount of oil is increased, the wear resistance deteriorates, and if the amount of oil is decreased, the grip performance deteriorates. There is a problem.

Therefore, in order to obtain a rubber composition with good wear resistance and grip performance with high productivity without increasing the amount of oil, not only carbon black or silica is used alone as a reinforcing filler, but also silica and Combined with carbon black, further improve the rubber component so that it has a wide interaction with such various fillers and gives good dispersibility of the filler and wear resistance of the rubber composition. Many technological developments have been made on modified rubber. Among them, in particular, a modified polymer in which an alkoxysilane having a dialkylamino group is introduced into the active terminal of a polymer obtained by anionic polymerization using alkyllithium or lithium amide as a polymerization initiator is disclosed (Patent Document 1). 2). However, the rubber composition containing such a modified conjugated diene polymer has a problem that dry maneuverability is lowered.
As described above, it has been difficult to obtain a rubber composition balanced at a high level of grip performance and wear resistance.

Japanese Patent Publication No. 6-53763 Japanese Examined Patent Publication No. 6-57767

  An object of the present invention is to provide a rubber composition for a tire tread having excellent grip performance and wear resistance, and a pneumatic tire using the same.

The present inventor has conducted extensive research to achieve the above object, and as a result, a rubber component containing a modified conjugated diene polymer obtained by a specific method and natural rubber and / or diene synthetic rubber in a predetermined ratio. On the other hand, it has been found that the object can be achieved by a rubber composition comprising a reinforcing filler composed of silica and carbon black and a resin in a predetermined ratio, and the present invention is completed based on this finding. It came.
That is, the present invention
(1) (A-1) Modified conjugated diene polymer obtained by modifying the active terminal of a conjugated diene polymer having a cis-1,4-bond content of 75 mol% or more with at least a hydrocarbyloxysilane compound 5 to 50% by mass and (A-2) rubber component (A) containing natural rubber and / or diene synthetic rubber and 100 parts by mass of rubber component (B-1) 50 to 95% by mass of silica and ( B-2) A rubber composition for tire tread containing reinforcing filler (B) 60 to 140 parts by mass and (C) resin 5 to 60 parts by mass comprising 50 to 5% by mass of carbon black.
(2) Furthermore, the rubber composition for tire tread which contains 10-135 mass parts of softening agents, such as (D) oil, with respect to 100 mass parts of (A) component is a preferable aspect.
The modified conjugated diene polymer of component (A-1) may be first modified with a hydrocarbyloxysilane compound in the presence of a condensation accelerator after the primary modification of the active end with a hydrocarbyloxysilane compound. The primary modification may be followed by reaction with a carboxylic acid partial ester of a polyhydric alcohol.

  ADVANTAGE OF THE INVENTION According to this invention, while being excellent in grip performance, the rubber composition for tire treads which has abrasion resistance, and a pneumatic tire using the same can be provided.

  The rubber composition for a tire tread of the present invention (hereinafter sometimes simply referred to as a rubber composition) includes, as essential components, (A-1) a modified conjugated diene polymer and (A-2) natural rubber and / or A rubber component (A) containing a diene synthetic rubber, (B-1) a reinforcing filler (B) comprising 50 to 95% by mass of silica and (B-2) 50 to 5% by mass of carbon black, and (C ) A resin is contained, and it contains other inorganic fillers and softeners such as oil, and other components appropriately selected as necessary.

(A) Rubber component (A-1) Modified conjugated diene polymer (A-1) The modified conjugated diene polymer contained in the rubber component (A) is a cis-1,4-bond content. Are those obtained by modifying at least hydrocarbyloxysilane with an active terminal of a conjugated diene polymer having a molar ratio of 75 mol% or more.
The conjugated diene polymer having an active terminal with a cis-1,4-bond content of 75 mol% or more used as an intermediate of the modified conjugated diene polymer is a conjugated diene monomer alone or another monomer. At the same time, it can be produced by polymerizing by the following polymerization catalyst using a method such as a solution polymerization method, a gas phase polymerization method and a bulk polymerization method, preferably a solution polymerization method. The polymerization mode may be either a batch type or a continuous type.

Examples of the raw material monomer conjugated diene compound include 1,3-butadiene, isoprene, 1,3-pentadiene, 2,3-dimethylbutadiene, 2-phenyl-1,3-butadiene, 1,3-hexadiene, and the like. . These may be used alone or in combination of two or more, and among these, 1,3-butadiene is particularly preferable.
Further, a small amount of other hydrocarbon monomers may coexist in these conjugated diene compounds, but the conjugated diene compound is preferably 80 mol% or more of the total monomers.

The polymerization catalyst is preferably a combination of at least one compound selected from the following components (x), (y) and (z).
[(X) component]
The rare earth compound selected from the following (x1) to (x4) may be used as it is as an inert organic solvent solution or may be supported on an inert solid.
(X1) a rare earth compound having an oxidation number of 3, a carboxylic acid group having 2 to 30 carbon atoms, an alkoxy group having 2 to 30 carbon atoms, an aryloxy group having 6 to 30 carbon atoms, and 1,3-carbon having 5 to 30 carbon atoms One having a total of three ligands freely selected from dicarbonyl-containing hydrocarbon groups, or a Lewis base compound (in particular, free carboxylic acid, free alcohol, 1,3-diketone, cyclic ether, linear chain) Complex ethers, trihydrocarbyl phosphines, trihydrocarbyl phosphites, etc.). Specific examples include neodymium tri-2-ethylhexanoate, a complex compound thereof with acetylacetone, neodymium trineodecanoate, a complex compound thereof with acetylacetone, neodymium tri-n-butoxide, and the like.

(X2) A complex compound of a rare earth trihalide and a Lewis base. For example, there is a THF complex of neodymium trichloride.
(X3) An organic rare earth compound having an oxidation number of 3 in which at least one (substituted) allyl group is directly bonded to a rare earth atom. For example, there is a salt of tetraallyl neodymium and lithium.
(X4) an organic rare earth compound having an oxidation number of 2 or 3 in which at least one (substituted) cyclopentadienyl group is directly bonded to a rare earth atom, or an ion composed of this compound and trialkylaluminum or a non-coordinating anion and a counter cation It is a reaction product with a functional compound. An example is dimethylaluminum (μ-dimethyl) bis (pentamethylcyclopentadienyl) samarium.

As the rare earth element of the rare earth compound, lanthanum, neodymium, praseodymium, samarium and gadolinium are preferable, and among these, lanthanum, neodymium and samarium are more preferable.
Among the above components (x), neodymium carboxylates and samarium substituted cyclopentadienyl compounds are preferred.

[(Y) component]
A plurality of organoaluminum compounds selected from the following one can be used at the same time.
(Y1) A trihydrocarbyl aluminum compound represented by the formula R ¹² ₃ A1 (wherein R ¹² is a hydrocarbon group having 1 to 30 carbon atoms and may be the same or different from each other).
(Y2) Hydrocarbyl aluminum hydride represented by the formula R ¹³ ₂ A1H or R ¹³ A1H ₂ (wherein R ¹³ is a hydrocarbon group having 1 to 30 carbon atoms, which may be the same or different from each other).
(Y3) A hydrocarbylaluminoxane compound having a hydrocarbon group having 1 to 30 carbon atoms.
Examples of the component (y) include trialkylaluminum, dialkylaluminum hydride, alkylaluminum dihydride, and alkylaluminoxane. These compounds may be used as a mixture. Among the components (y), a combination of an aluminoxane and another organoaluminum compound is preferable.

[(Z) component]
Although it is a compound selected from the following ones, it is not always necessary when (x) contains a halogen or a non-coordinating anion and (y) contains an aluminoxane.
(Z1) An inorganic or organic compound of an element belonging to Group II, III, or IV having a hydrolyzable halogen (short period type) or a complex compound of these with a Lewis base. For example, alkyl aluminum dichloride, dialkyl aluminum chloride, silicon tetrachloride, tin tetrachloride, a complex of zinc chloride and a Lewis base such as alcohol, a complex of magnesium chloride and a Lewis base such as alcohol, or the like.
(Z2) An organic halide having a structure selected from at least one tertiary alkyl halide, benzyl halide, and allyl halide. For example, benzyl chloride, t-butyl chloride, benzyl bromide, t-butyl bromide and the like.
(Z3) A zinc halide or a complex compound of this with a Lewis base.
(Z4) An ionic compound comprising a non-coordinating anion and a counter cation. An example is triphenylcarbonium tetrakis (pentafluorophenyl) borate.

For the preparation of the catalyst, in addition to the components (x), (y), and (z), the same conjugated diene compound and / or non-conjugated diene monomer as the polymerization monomer is used in combination as necessary. May be. Further, a part or all of the component (x) or the component (z) may be supported on an inert solid, and in this case, it can be carried out by so-called gas phase polymerization.
Although the usage-amount of the said catalyst can be set suitably, normally (x) component is about 0.001-0.5 millimoles per 100g of monomers. Moreover, (y) component / (x) component is about 5-1000 and (z) component / (x) component is about 0.5-10 by molar ratio.

  Examples of the solvent used in the case of solution polymerization include organic solvents inert to the reaction, for example, hydrocarbon solvents such as aliphatic, alicyclic, and aromatic hydrocarbon compounds. Specifically, those having 3 to 8 carbon atoms are preferred, such as propane, n-butane, isobutane, n-pentane, isopentane, n-hexane, cyclohexane, propene, 1-butene, isobutene, trans-2-butene, Examples thereof include cis-2-butene, 1-pentene, 2-pentene, 1-hexene, 2-hexene, benzene, toluene, xylene, and ethylbenzene. These may be used alone or in combination of two or more.

The temperature in this polymerization reaction is preferably selected in the range of −80 to 150 ° C., more preferably −20 to 120 ° C. The polymerization reaction can be carried out under generated pressure, but it is usually desirable to operate at a pressure sufficient to keep the monomer in a substantially liquid phase. That is, the pressure will depend on the particular material being polymerized, the polymerization medium used and the polymerization temperature, but higher pressures can be used if desired, and such a pressure can be used with a gas inert to the polymerization reaction. It can be obtained by an appropriate method such as pressurization.
In this polymerization reaction, it is desirable that all raw materials involved in the polymerization, such as a catalyst, a solvent, a monomer, etc., from which reaction inhibitors such as water, oxygen, carbon dioxide, and protic compounds are substantially removed are used.

  The modified conjugated diene polymer used in the present invention is a conjugated diene polymer (intermediate polymer) having an active terminus having a cis-1,4-bond content of 75 mol% or more thus obtained. The active terminal is modified by at least a hydrocarbyloxysilane compound, and there are five modes shown below.

First, the first embodiment is a modified conjugated diene system in which the active terminal of the intermediate polymer is first modified with a hydrocarbyloxysilane compound and then secondarily modified with a hydrocarbyloxysilane compound in the presence of a condensation accelerator. It is a polymer.
The second aspect is a modified conjugated diene polymer obtained by first reacting the active terminal of the intermediate polymer with a hydrocarbyloxysilane compound and then reacting with a carboxylic acid partial ester of a polyhydric alcohol.
In a third aspect, the hydrocarbyloxysilane compound residue and the unreacted hydrocarbyloxysilane introduced into the terminal after the primary modification of the active end of the intermediate polymer with a hydrocarbyloxysilane compound and further in the presence of a condensation accelerator It is a modified conjugated diene polymer obtained by condensation reaction with a compound.
A fourth aspect is a modified conjugated diene polymer obtained by reacting with a carboxylic acid partial ester of a polyhydric alcohol after the second modification in the first aspect.
The fifth aspect is a modified conjugated diene polymer obtained by further reacting with a carboxylic acid partial ester of a polyhydric alcohol after the condensation reaction in the third aspect.

In the primary modification reaction in each of the above-described embodiments, the intermediate polymer used preferably has at least 10% of polymer chains having a living property.
Examples of the hydrocarbyloxysilane compound used for modification include at least one compound selected from compounds represented by the following general formula (I), general formula (II), and general formula (III), and partial condensates thereof. it can.

[Wherein A ¹ is (thio) epoxy, (thio) isocyanate, (thio) ketone, (thio) aldehyde, imine, amide, isocyanuric acid trihydrocarbyl ester, (thio) carboxylic acid ester, (thio) carboxylic acid A monovalent group having at least one functional group selected from a metal salt, a carboxylic acid anhydride, a carboxylic acid halide, and a dihydrocarbyl carbonate ester, R ¹ is a single bond or a divalent inert hydrocarbon group , R ² and R ³ each independently represent a monovalent aliphatic hydrocarbon group having 1 to 20 carbon atoms or a monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms, and n is an integer of 0 to 2 , and the case where R ² is plural, R ² may be the same or different, if the OR ³ there are a plurality, the plurality of OR ³ may be the same or different, and in the molecule active Proton and onium salt are not included. ]

Including in the formula (I), in the functional groups in A ^1, imine ketimine, aldimine, include amidine, a (thio) carboxylic acid esters, unsaturated carboxylic acid esters such as acrylates and methacrylates. Examples of the metal of the metal salt of (thio) carboxylic acid include alkali metals, alkaline earth metals, Al, Sn, and Zn.

Preferred examples of the divalent inert hydrocarbon group in R ¹ include an alkylene group having 1 to 20 carbon atoms. The alkylene group may be linear, branched or cyclic, but is particularly preferably linear. 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.
Examples of R ² and R ³ include 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 group having 7 to 18 carbon atoms. 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 group, tert-butyl group, pentyl group, hexyl group, octyl group, decyl group, dodecyl group, cyclopentyl group, cyclohexyl group, vinyl group, propenyl group, allyl group, hexenyl group, octenyl group, cyclopentenyl group, cyclohexenyl group, etc. Is mentioned. In addition, 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.

  n is an integer of 0 to 2, but 0 is preferable, and it is necessary that this molecule has no active proton and onium salt.

  Examples of the hydrocarbyloxysilane compound represented by the general formula (I) include (thio) epoxy group-containing hydrocarbyloxysilane compounds such as 2-glycidoxyethyltrimethoxysilane, 2-glycidoxyethyltriethoxysilane, ( 2-glycidoxyethyl) methyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, (3-glycidoxypropyl) methyldimethoxysilane, 2- (3,4- Epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane, 2- (3,4-epoxycyclohexyl) ethyl (methyl) dimethoxysilane and epoxy compounds in these compounds as thioepoxy groups Replace May be preferably exemplified things, among these, in particular 3-glycidoxypropyltrimethoxysilane and 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane are preferable.

  As imine group-containing hydrocarbyloxycyan compounds, N- (1,3-dimethylbutylidene) -3- (triethoxysilyl) -1-propanamine, N- (1-methylethylidene) -3- (triethoxysilyl) -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 triethoxysilyl compounds Trimethoxysilyl compounds, methyldiethoxysilyl compounds, ethyldiethoxysilyl compounds, methyl Preferable examples include methoxysilyl compounds and ethyldimethoxysilyl compounds. Among these, N- (1-methylpropylidene) -3- (triethoxysilyl) -1-propanamine and N- (1 , 3-Dimethylbutylidene) -3- (triethoxysilyl) -1-propanamine is preferred.

  Furthermore, the following can be mentioned as another hydrocarbyloxy compound. That is, as imine (amidine) group-containing compounds, 1- [3- (triethoxysilyl) propyl] -4,5-dihydroimidazole, 1- [3- (trimethoxysilyl) propyl] -4,5-dihydro Examples thereof include imidazole, 3- [10- (triethoxysilyl) decyl] -4-oxazoline, and among these, 3- (1-hexamethyleneimino) propyl (triethoxy) silane, (1-hexa Methyleneimino) methyl (trimethoxy) silane, 1- [3- (triethoxysilyl) propyl] -4,5-dihydroimidazole and 1- [3- (trimethoxysilyl) propyl] -4,5-dihydroimidazole are preferred Can be mentioned. N- (3-triethoxysilylpropyl) -4,5-dihydroimidazole, N- (3-isopropoxysilylpropyl) -4,5-dihydroimidazole, N- (3-methyldiethoxysilylpropyl)- 4,5-dihydroimidazole and the like can be mentioned, and among them, N- (3-triethoxysilylpropyl) -4,5-dihydroimidazole is preferable.

  Examples of the carboxylic acid ester group-containing compound include 3-methacryloyloxypropyltriethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-methacryloyloxypropylmethyldiethoxysilane, and 3-methacryloyloxypropyltriisopropoxysilane. Among them, 3-methacryloyloxypropyltrimethoxysilane is preferable among them.

  Furthermore, examples of the isocyanate group-containing compound include 3-isocyanatopropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-isocyanatopropylmethyldiethoxysilane, and 3-isocyanatopropyltriisopropoxysilane. Of these, 3-isocyanatopropyltriethoxysilane is preferred.

  Examples of the carboxylic acid anhydride-containing compound include 3-triethoxysilylpropyl succinic anhydride, 3-trimethoxysilylpropyl succinic anhydride, 3-methyldiethoxysilylpropyl succinic anhydride, and the like. Of these, 3-triethoxysilylpropyl succinic anhydride is preferred.

  One of these hydrocarbyloxysilane compounds may be used alone, or two or more thereof may be used in combination. Moreover, the partial condensate of the said hydrocarbyl oxysilane compound can also be used.

［式中、Ａ^２は、環状三級アミン、非環状三級アミン、ピリジン、スルフィド及びマルチスルフィドの中から選ばれる少なくとも１種の官能基を有する一価の基、Ｒ^４は脂肪族炭化水素または芳香族炭化水素基、Ｒ^５及びＲ^６は、それぞれ独立に炭素数１〜２０の一価の脂肪族炭化水素基又は炭素数６〜１８の一価の芳香族炭化水素基を示し、ｍは０〜２の整数であり、Ｒ^５が複数ある場合、複数のＲ^５は同一でも異なっていてもよく、ＯＲ^６が複数ある場合、複数のＯＲ^６は同一でも異なっていてもよく、また分子中には活性プロトン及びオニウム塩は含まれない。］
で表される化合物及び／又はその部分縮合物が使用できる。 Next, as the hydrocarbyloxysilane compound, the general formula (II)

Wherein, A ² is a cyclic tertiary amine, acyclic tertiary amine, pyridine, monovalent group having at least one functional group selected from among sulfides and multi sulfide, R ⁴ is an aliphatic hydrocarbon Or an aromatic hydrocarbon group, R ⁵ and R ⁶ 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; is an integer of 0 to 2, if R ⁵ there are a plurality, the plurality of R ⁵ may be the same or different, if OR ⁶ there are plural, a plurality of OR ⁶ may be the same or different, and The molecule does not contain active protons and onium salts. ]
And / or a partial condensate thereof can be used.

  The hydrocarbyloxysilane compound represented by the general formula (II) and / or the partial condensate thereof was introduced into the active end because the direct reaction with the active end does not substantially occur and remains unreacted in the reaction system. Consumed for condensation with hydrocarbyloxysilane compound residues.

In the general formula (II), the acyclic tertiary amine in A ² contains an N, N- (disubstituted) aromatic amine such as N, N- (disubstituted) aniline, and is also a cyclic tertiary amine. The amine can contain a (thio) ether as part of the ring. Divalent inactive hydrocarbon group among R ^4, the ^{R 5} and ^{R 6} are the same as those described for ^R 1, ^{R 2} and ^{R 3} in each of the general formula (I). It is necessary that this molecule does not have active protons and onium salts.

  Examples of the hydrocarbyloxysilane compound represented by the general formula (II) include 3-dimethylaminopropyl (triethoxy) silane and 3-dimethylaminopropyl (trimethoxy) silane as acyclic tertiary amine group-containing hydrocarbyloxysilane compounds. 3-diethylaminopropyl (triethoxy) silane, 3-diethylaminopropyl (trimethoxy) silane, 2-dimethylaminoethyl (triethoxy) silane, 2-dimethylaminoethyl (trimethoxy) silane, 3-dimethylaminopropyl (diethoxy) methylsilane, 3 -Dibutylaminopropyl (triethoxy) silane etc. are mentioned, among these, 3-diethylaminopropyl (triethoxy) silane and 3-dimethylaminopropyl (triethoxy) silane are Masui.

  Further, as the cyclic tertiary amine group-containing hydrocarbyloxysilane compound, 3- (1-hexamethyleneimino) propyl (triethoxy) silane, 3- (1-hexamethyleneimino) propyl (trimethoxy) silane, (1-hexamethyleneimino) ) Methyl (trimethoxy) silane, (1-hexamethyleneimino) methyl (triethoxy) silane, 2- (1-hexamethyleneimino) ethyl (triethoxy) silane, 2- (1-hexamethyleneimino) ethyl (trimethoxy) silane, 3- (1-pyrrolidinyl) propyl (triethoxy) silane, 3- (1-pyrrolidinyl) propyl (trimethoxy) silane, 3- (1-heptamethyleneimino) propyl (triethoxy) silane, 3- (1-dodecamethyleneimino) Propyl (triethoxy) Run, 3- (1-hexamethyleneimino) propyl (diethoxy) methylsilane, 3- (1-hexamethyleneimino) can be mentioned propyl (diethoxy) ethylsilane. Of these, 3- (1-hexamethyleneimino) propyl (triethoxy) silane is preferred.

  Furthermore, examples of other hydrocarbyloxysilane compounds include 2- (trimethoxysilylethyl) pyridine, 2- (triethoxysilylethyl) pyridine, 4-ethylpyridine and the like.

  One of these hydrocarbyloxysilane compounds may be used alone, or two or more thereof may be used in combination. Moreover, the partial condensate of these hydrocarbyl oxysilane compounds can also be used.

［式中、Ａ^３は、アルコール、チオール、一級アミン及びそのオニウム塩、環状二級アミン及びそのオニウム塩、非環状二級アミン及びそのオニウム塩、環状三級アミンのオニウム塩、非環状三級アミンのオニウム塩、アリール又はアリールアルキルＳｎ結合を有する基、スルフォニル、スルフィニル及びニトリルから選ばれる少なくとも一種の官能基を有する一価の基、Ｒ^７は単結合又は二価の不活性炭化水素基、Ｒ^８及びＲ^９は、それぞれ独立に炭素数１〜２０の一価の脂肪族炭化水素基又は炭素数６〜１８の一価の芳香族炭化水素基を示し、ｑは０〜２の整数であり、Ｒ^８が複数ある場合、複数のＲ^８は同一でも異なっていてもよく、ＯＲ^９が複数ある場合、複数のＯＲ^９は同一でも異なっていてもよい。］
で表される化合物及び／又は部分縮合物が使用できる。 The hydrocarbyloxysilane compound further includes a general formula (III)

[Wherein A ³ represents alcohol, thiol, primary amine and onium salt thereof, cyclic secondary amine and onium salt thereof, acyclic secondary amine and onium salt thereof, onium salt of cyclic tertiary amine, acyclic tertiary amine An onium salt of an amine, a group having an aryl or arylalkyl Sn bond, a monovalent group having at least one functional group selected from sulfonyl, sulfinyl and nitrile, R ⁷ is a single bond or a divalent inert hydrocarbon group, R ⁸ and R ⁹ each independently represent a monovalent aliphatic hydrocarbon group having 1 to 20 carbon atoms or a monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms, and q is an integer of 0 to 2. There, if R ⁸ is plural, R ⁸ may be the same or different, if the OR ⁹ there are a plurality, the plurality of OR ⁹ may be the same or different. ]
And / or a partial condensate thereof can be used.

In the general formula (III), the primary amine in A ³ includes aromatic amines such as aniline, and the acyclic secondary amine is N- (monosubstituted) aromatic such as N- (monosubstituted) aniline. Includes amines. Further, onium salts of acyclic tertiary amines include onium salts of N, N- (disubstituted) aromatic amines such as N, N- (disubstituted) aniline. Also. In the case of a cyclic secondary amine or a cyclic tertiary amine, (thio) ether can be included as a part of the ring. Divalent inactive hydrocarbon group out of R ^7, the ^{R 8} and ^{R 9} are the same as those described for ^R 1, ^{R 2} and ^{R 3} in each of the general formula (I).

  Examples of the hydrocarbyloxysilane compound represented by the general formula (III) include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, hydroxymethyltrimethoxysilane, hydroxymethyltriethoxysilane, mercaptomethyltrimethoxy. Silane, mercaptomethyltriethoxysilane, aminophenyltrimethoxysilane, aminophenyltriethoxysilane, 3- (N-methylamino) propyltrimethoxysilane, 3- (N-methylamino) propyltriethoxysilane, octadecyldimethyl (3 -Trimethylsilylpropyl) ammonium chloride, octadecyldimethyl (3-triethylsilylpropyl) ammonium chloride, cyanomethyltrimethoxysilane, cyanomethyltrie Kishishiran, can be exemplified sulfonyl methyltrimethoxysilane, sulfonyl methyltriethoxysilane, sulfinyl methyltrimethoxysilane, a sulfinyl methyl triethoxysilane.

One of these hydrocarbyloxysilane compounds may be used alone, or two or more thereof may be used in combination. Moreover, the partial condensate of the said hydrocarbyl oxysilane compound can also be used.
In addition, the partial condensate of the hydrocarbyloxysilane compound represented by the general formulas (I), (II), and (III) is a part of SiOR of the hydrocarbyloxysilane compound (not all), and SiOSi Say something combined.

  In the present invention, in the case of the first aspect, the third aspect, the fourth aspect, and the fifth aspect, the reaction with the remaining or newly added hydrocarbyloxysilane compound in the presence of a condensation accelerator. First, an intermediate polymer having an active end reacts with a substantially stoichiometric amount of a hydrocarbyloxysilane compound added to the reaction system to introduce a hydrocarbyloxysilyl group at substantially all of the ends. (Primary modification), and by reacting the hydrocarbyloxysilyl compound with the hydrocarbyloxysilyl group introduced above, more hydrocarbyloxysilane compound residues than the equivalent amount are introduced into the active terminal.

  In the present invention, when the hydrocarbyloxysilane compound is an alkoxysilyl compound, the condensation reaction between alkoxysilyl groups in the first aspect, the third aspect, the fourth aspect, and the fifth aspect is (residual or It preferably occurs between the newly added free alkoxysilane and the alkoxysilyl group at the end of the polymer, and in some cases, preferably occurs between the alkoxysilyl groups at the end of the polymer. is necessary. Therefore, when an alkoxysilane compound is newly added, it is preferable from the viewpoint of efficiency that the hydrolyzability of the alkoxysilyl group does not exceed the hydrolyzability of the alkoxysilyl group at the polymer terminal. For example, a trimethoxysilyl group-containing compound having a large hydrolyzability is used for the primary modified alkoxysilane I, and an alkoxysilyl group (for example, a triethoxysilyl group) having a lower hydrolyzability than the newly added alkoxysilane II. A combination using a compound containing is preferred. On the contrary, for example, it is included in the scope of the present invention that alkoxysilane I contains a triethoxysilyl group and II contains a trimethoxysilyl group, but it is not preferable from the viewpoint of reaction efficiency.

The denaturation reaction in the present invention may be either a solution reaction or a solid phase reaction, but a solution reaction (a solution containing an unreacted monomer used during polymerization may be suitable). Moreover, there is no restriction | limiting in particular about the form of this modification | denaturation reaction, You may carry out using a batch type reactor, You may carry out by a continuous type using apparatuses, such as a multistage continuous type reactor and an in-line mixer. In addition, it is important to carry out the modification reaction after completion of the polymerization reaction and before performing various operations necessary for solvent removal treatment, water treatment, heat treatment, polymer isolation, and the like.
As the temperature of the modification reaction, the polymerization temperature of the conjugated diene polymer can be used as it is. Specifically, a preferable range is 20 to 100 ° C. If the temperature is low, the viscosity of the polymer tends to increase, and if the temperature is high, the polymerization active terminal tends to be deactivated.

  Next, in order to accelerate the secondary modification, it is preferably performed in the presence of a condensation accelerator. As this condensation accelerator, a combination of a metal compound generally known as a curing catalyst for alkoxy condensation curable room temperature crosslinking (RTV) silicone and water can be used. For example, a combination of tin carboxylate and / or titanium alkoxide and water can be preferably mentioned. There is no particular limitation on the method of charging the condensation accelerator into the reaction system. A solution of an organic solvent compatible with water such as alcohol may be used, or water may be directly injected, dispersed, or dissolved in the hydrocarbon solution using various chemical engineering techniques.

  Such a condensation accelerator is preferably composed of at least one compound selected from the compounds represented by formula (IV), formula (V) and formula (VI) and water. .

Carbonate having 3 to 20 carbon atoms of tin of oxidation number 2 represented by general formula (IV):
Sn (OCOR ¹⁰ ) ₂ .... (IV)
[Wherein, R ¹⁰ is an alkyl group having 2 to 19 carbon atoms, and when there are a plurality of them, they may be the same or different. ]

Tin compound of oxidation number 4 represented by general formula (V):
R ¹¹ _r SnA ⁴ _t B ¹ _(4- tr ₎ (V)
[Wherein, r is an integer of 1 to 3, t is an integer of 1 or 2, and t + r is an integer of 3 or 4. R ¹¹ is an aliphatic hydrocarbon group having 1 to 30 carbon atoms, and B ¹ is a hydroxyl group or a halogen. A ⁴ represents (a) an aliphatic carboxylic acid residue having 2 to 30 carbon atoms, (b) a 1,3-dicarbonyl-containing hydrocarbon group having 5 to 30 carbon atoms, and (c) a hydrocarbyl having 3 to 30 carbon atoms. A group selected from an oxy group and (d) a siloxy group having a total of three substitutions (which may be the same or different) with a hydrocarbyl group having 1 to 20 carbon atoms and / or a hydrocarbyloxy group having 1 to 20 carbon atoms. , R ¹¹ may be the same or different when there are a plurality of R ¹¹ , and may be the same or different when there are a plurality of A ⁴ . ]

Titanium compound having an oxidation number of 4 represented by the general formula (VI):
A ⁵ _x TiB ² _(4-x) (VI)
[Wherein x is an integer of 2 or 4. A ⁵ is (1) a C 3-30 hydrocarbyloxy group, (2) a C 1-30 alkyl group and / or a C 1-20 hydrocarbyloxy group, which is a total of three substituted siloxy groups, If the A ⁵ there are a plurality may be the same or different. B ² is a 1,3-dicarbonyl-containing hydrocarbon group having 5 to 30 carbon atoms, and when there are a plurality of B ² , they may be the same or different. ]

  Examples of the carboxylic acid salt of tin having an oxidation number of 2 represented by the general formula (IV) include bis (2-ethylhexanoic acid) tin, tin dioleate and tin dilaurate represented by the general formula (V). Among the tin compounds having an oxidation number of 4 which are used, examples of the tin carboxylate of (a) include tetravalent dihydrocarbyltin dicarboxylates (including bis (hydrocarbyldicarboxylic acid) salts), monocarboxylates Hydroxide or the like (b) having a 1,3-dicarbonyl-containing hydrocarbon group having 5 to 30 carbon atoms includes bis (1,3-diketonate) and the like (c) having 3 to 30 carbon atoms. As those having a hydrocarbyloxy group, the alkoxy halide is (d) a total of three substitutions (even if they are the same) with a hydrocarbyl group having 1 to 20 carbon atoms and / or a hydrocarbyloxy group having 1 to 20 carbon atoms. Examples of those having a siloxy group which may have been made include alkoxy (trihydrocarbylsiloxide), alkoxy (dihydrocarbylalkoxysiloxide), bis (trihydrocarbylsiloxide), bis (dihydrocarbylalkoxysiloxide) and the like Are preferable. The hydrocarbon group condensed with tin preferably has 4 or more carbon atoms, and more preferably has 4 to 8 carbon atoms.

  Further, as the titanium compound having an oxidation number of 4 represented by the general formula (VI), tetraalkoxide or tetrakis (trihydrocarbyloxysiloxide) of titanium having an oxidation number of 4 or diisopropoxybis (acetylacetonate) titanium Dialkoxybis (1,3-diketonate) titanium and the like.

  The water in the condensation accelerator is preferably used in the form of a simple substance, a solution of alcohol or the like, or a dispersed micelle in a hydrocarbon solvent, and if necessary, such as adsorbed water on the solid surface or hydrated water of hydrate. Water that is potentially contained in a compound capable of releasing water in the reaction system can also be used effectively.

  The metal compound and water forming the condensation accelerator may be added separately to the reaction system or mixed immediately before use as a mixture, but long-term storage of the mixture is preferable because it causes decomposition of the metal compound. Absent.

  As the use amount of the condensation accelerator, it is preferable that the molar ratio of the metal of the metal compound and the water effective for the reaction to the total amount of hydrocarbyloxysilyl groups present in the reaction system is 0.1 or more. . Although the upper limit varies depending on the purpose and reaction conditions, it is preferable that there is effective water having a molar ratio of about 0.5 to 3 with respect to the total amount of hydrocarbyloxysilyl groups condensed at the polymer terminal before the condensation treatment. The molar ratio of the metal of the metal compound to water effective for the reaction varies depending on the required reaction conditions, but is preferably about 1: 0.5 to 1:20.

In the second aspect, the fourth aspect and the fifth aspect of the modified conjugated diene polymer used as the component (A-1) in the present invention, a carboxylic acid partial ester of a polyhydric alcohol is used as a polymerization terminal. An operation for reacting with a group derived from a hydrocarbyloxysilane compound introduced into the group to stabilize the group is performed.
Here, the carboxylic acid partial ester of a polyhydric alcohol is an ester of a polyhydric alcohol and a carboxylic acid and means a partial ester having one or more hydroxyl groups. Specifically, an ester of a saccharide having 4 or more carbon atoms or a modified saccharide and a fatty acid is preferably used. This ester is more preferably (i) a fatty acid partial ester of a polyhydric alcohol, particularly a partial ester of a saturated higher fatty acid having 10 to 20 carbon atoms or an unsaturated higher fatty acid and a polyhydric alcohol (monoester, diester, triester). And (b) an ester compound in which 1 to 3 partial esters of a polyvalent carboxylic acid and a higher alcohol are bonded to the polyhydric alcohol.

  The polyhydric alcohol used as the raw material for the partial ester is preferably a saccharide having 5 or 6 carbon atoms having at least three hydroxyl groups (which may be hydrogenated or not hydrogenated), glycol, A polyhydroxy compound or the like is used. The raw fatty acid is preferably a saturated or unsaturated fatty acid having 10 to 20 carbon atoms, and for example, stearic acid, lauric acid, and palmitic acid are used.

Among the fatty acid partial esters of polyhydric alcohols, sorbitan fatty acid esters are preferred, specifically sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan tristearate, sorbitan monooleate and And sorbitan trioleate.
Commercially available products include “SPAN60” (sorbitan stearate), “SPAN80” (sorbitan monooleate), “SPAN85” (sorbitan trioleate) and the like as trademarks of ICI.
The amount of the partial ester added is preferably about 0.2 to 10 mol, particularly 1 to 10 mol, relative to 1 mol of the hydrocarbyloxysilyl group imparted to the intermediate polymer.

As the modified conjugated diene polymer of the component (A-1) thus produced, a modified polybutadiene having a cis-1,4-bond amount of 75 mol% or more is the performance of the rubber composition for tire treads. This is preferable from the point of view.
The modified conjugated diene polymer of the component (A-1) has a large dispersion improving effect on the reinforcing filler, particularly silica, and reduces E ′ (dynamic storage elastic modulus) in the whole temperature range as a whole. In particular, the decrease in E ′ on the low temperature side can be increased. Therefore, the grip performance of the tire can be further improved.
In addition, the loss factor (tan δ) is greatly reduced, and compared to the case of using ordinary polybutadiene rubber, it is possible to increase the decrease in high temperature (60 ° C) while reducing the decrease in 0 ° C. Therefore, even when highly filled silica is blended, it also works to improve the balance between grip performance and fuel efficiency. Further, the wear resistance can be improved by the effect of improving the dispersion of the reinforcing filler.

In the rubber composition of the present invention, the content of the (A-1) modified conjugated diene polymer in the rubber component (A) is 5 to 50% by mass, preferably 10 to 50% by mass. When the content is less than 5% by mass, the above effect is not sufficiently exhibited, and when it exceeds 50% by mass, the kneading workability is deteriorated.
On the other hand, as (A-2) natural rubber and / or diene synthetic rubber, in addition to natural rubber, for example, polyisoprene synthetic rubber (IR), polybutadiene rubber (BR), styrene-butadiene rubber (SBR), acrylonitrile butadiene Examples thereof include rubber (NBR), chloroprene rubber (CR), and butyl rubber (IIR). The natural rubber and / or diene synthetic rubber of component (A-2) may be used alone or in combination of two or more.

  In the rubber composition of the present invention, the component (B) is added to the modified conjugated diene polymer in order to impart good grip performance, performance such as low fuel consumption and wear resistance, and reinforcement. As a reinforcing filler, a high content of (B-1) silica and (B-2) carbon black is blended.

There is no restriction | limiting in particular as (B-1) component silica, It can select and use arbitrarily from what is conventionally used as a filler for reinforcement of rubber conventionally. For example, wet silica (hydrous silicic acid), dry silica (anhydrous silicic acid), calcium silicate, aluminum silicate, and the like can be mentioned. Among them, wet silica that has a remarkable effect of improving low heat buildup and gripping properties is preferable. The wet silica preferably has a nitrogen adsorption specific surface area (N ₂ SA) according to the BET method of 70 to 280 m ² / g in terms of balance of reinforcement, workability, grip properties, and wear resistance, and the like. More preferably, it is -250 m < ² > / g. Suitable wet silica includes, for example, AQ, VN3, LP, NA, etc. manufactured by Tosoh Silica Co., Ltd. and Ultrazil VN3 (N ₂ SA: 210 m ² / g) manufactured by Degussa.

  (B-2) Component carbon black is not particularly limited. For example, SRF, GPF, FEF, HAF, ISAF, SAF and the like are used, and carbon black having a dibutyl phthalate oil absorption (DBP) of 80 ml / 100 g or more is preferable. . By using carbon black, the effect of improving grip performance and wear resistance is increased, but HAF, ISAF, and SAF, which are particularly excellent in wear resistance, are more preferable.

In the reinforcing filler of component (B), the content ratio of silica and carbon black is 50 to 95% by mass of silica and 50 to 5% by mass of carbon black from the viewpoint of obtaining a rubber composition having desired performance. Preferably, silica is 60 to 90% by mass and carbon black is 10 to 40% by mass.
Further, the content of the reinforcing filler of the component (B) is selected in the range of 60 to 140 parts by mass with respect to 100 parts by mass of the rubber component as the component (A). When the content is less than 60 parts by mass, the effect of improving wear resistance and grip performance is not sufficiently exhibited, and when it exceeds 140 parts by mass, workability is deteriorated.
Furthermore, in order to obtain a rubber composition having desired performance and good workability, the content of the silica is usually 30 to 133 parts by mass with respect to 100 parts by mass of the rubber component of the component (A). The amount of carbon black is usually 3 to 70 parts by weight, preferably 4 to 63 parts by weight, based on 100 parts by weight of the rubber component (A). .

In the rubber composition of the present invention, (E) a silane coupling agent can be contained for the purpose of further improving the performance of the component (B-1) silica.
Examples of silane coupling agents include bis (3-triethoxysilylpropyl) tetrasulfide, bis (3-triethoxysilylpropyl) trisulfide, bis (3-triethoxysilylpropyl) disulfide, and bis (2-triethoxysilyl). Ethyl) tetrasulfide, bis (3-trimethoxysilylpropyl) tetrasulfide, bis (2-trimethoxysilylethyl) tetrasulfide, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 2-mercaptoethyltri Methoxysilane, 2-mercaptoethyltriethoxysilane, 3-trimethoxysilylpropyl-N, N-dimethylthiocarbamoyl tetrasulfide, 3-triethoxysilylpropyl-N, N-dimethylthiocarba Yl tetrasulfide, 2-triethoxysilylethyl-N, N-dimethylthiocarbamoyl tetrasulfide, 3-trimethoxysilylpropylbenzothiazolyl tetrasulfide, 3-triethoxysilylpropylbenzothiazolyl tetrasulfide, 3-triethoxy Ethoxysilylpropyl methacrylate monosulfide, 3-trimethoxysilylpropyl methacrylate monosulfide, bis (3-diethoxymethylsilylpropyl) tetrasulfide, 3-mercaptopropyldimethoxymethylsilane, dimethoxymethylsilylpropyl-N, N-dimethylthiocarbamoyl Tetrasulfide, dimethoxymethylsilylpropylbenzothiazolyl tetrasulfide, and the like can be mentioned. Among these, bis (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, as the rubber component, a modified conjugated diene polymer having a functional group with high affinity for silica introduced at the molecular end is used, so the blending amount of the silane coupling agent is It can be reduced from the normal case. The blending amount of the preferable silane coupling agent varies depending on the type of the silane coupling agent and the like, but is usually selected in the range of 5 to 20% by mass with respect to silica. If the amount is small, the effect as a coupling agent is not sufficiently exhibited, and if it is large, the rubber component may be gelled. From the viewpoint of the effect as a coupling agent and the prevention of gelation, the preferable blending amount of this silane coupling agent is in the range of 5 to 18% by mass.

  In the rubber composition of the present invention, an inorganic filler (F) can be contained as desired for the purpose of improving physical properties. As this inorganic filler, the compound represented by the following general formula (VII) can be mentioned.

^{_{aM 1 · bSiO y · cH 2}} O ······ (VII)
[Wherein, M ¹ represents a metal selected from the group consisting of aluminum, magnesium, titanium, calcium, and zirconium, an oxide or hydroxide of these metals, and a hydrate thereof, or carbonic acid of these metals. It is at least 1 type chosen from a salt, and a, b, y, and c are an integer of 1-5, an integer of 0-10, an integer of 2-5, and an integer of 0-10, respectively. In the above formula, when both a and c are 0, the inorganic compound is at least one metal, metal oxide or metal hydroxide selected from aluminum, magnesium, titanium, calcium and zirconium. ]

Examples of the inorganic filler represented by the above formula include alumina (Al ₂ O ₃ ) such as γ-alumina and α-alumina, alumina monohydrate such as boehmite and diaspore (Al ₂ O ₃ .H ₂ O), gibbsite, Aluminum hydroxide such as bayerite [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), 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.), silicic acid Aluminum calcium (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], zirconium carbonate _{[Zr (CO 3) 2]} , hydrogen to correct electric charge as various zeolites Crystalline aluminosilicate, or the like can be used including alkali metal or alkaline earth metal. Further, it is preferable that M ¹ in the general formula (VII) is at least one selected from aluminum metal, aluminum oxide or hydroxide, and hydrates thereof, or aluminum carbonate.
These inorganic fillers represented by the above formula may be used alone or in combination of two or more.
(F) It is preferable to mix | blend 5-30 mass parts of inorganic filler with respect to 100 mass parts of rubber components, and it is more preferable to mix | blend 10-25 mass parts.

The rubber composition of the present invention contains (C) a resin for the purpose of improving grip properties. Examples of resins that can be used include thermoplastic resins having molecular weights of several hundred to several thousand, and resins that impart tackiness by blending with natural rubber or synthetic rubber. Use various natural resins and synthetic resins. Can do.
Specifically, natural resins such as rosin resins and terpene resins, synthetic resins such as petroleum resins, phenol resins, coal resins, and xylene resins can be used.

Examples of rosin resins include gum rosin, tall oil rosin, wood rosin, hydrogenated rosin, disproportionated rosin, polymerized rosin, modified rosin glycerin, pentaerythritol ester, etc., and terpene resins include α-pinene, Examples thereof include terpene resins such as β-pinene and dipentene, aromatic modified terpene resins, terpene phenol resins, and hydrogenated terpene resins.
Among these natural resins, a polymerized rosin, a terpene phenol resin, and a hydrogenated terpene resin are preferable from the viewpoint of the wear resistance and grip characteristics of the blended rubber composition.

Petroleum-based resin is a mixture of cracked oil fractions containing unsaturated hydrocarbons such as olefins and diolefins by-produced along with petrochemical basic raw materials such as ethylene and propylene, for example, by thermal decomposition of naphtha in the petrochemical industry. It is obtained by polymerization with a Del Crafts type catalyst.
The petroleum-based resin, C ₅ fraction (co) polymer obtained by aliphatic petroleum resin, a C ₉ fraction obtained by thermal cracking of naphtha (co) polymerization obtained by thermal cracking of naphtha aromatic petroleum resin obtained Te, the C ₅ fraction and C ₉ fraction copolymerized copolymerization petroleum resin obtained, hydrogenation system, dicyclopentadiene-based such as alicyclic compound-based petroleum resins, Examples thereof include petroleum resins such as styrene resins such as styrene, substituted styrene, and copolymers of styrene and other monomers.

The _{C 5} fraction obtained by thermal cracking of naphtha, usually 1-pentene, 2-pentene, 2-methyl-1-butene, 2-methyl-2-butene, 3-methyl-1-olefin such as butene Examples include hydrocarbons, diolefinic hydrocarbons such as 2-methyl-1,3-butadiene, 1,2-pentadiene, 1,3-pentadiene, and 3-methyl-1,2-butadiene.
Also, the C ₉ fraction (co) polymerized aromatic petroleum resin obtained, a vinyl toluene, a resin obtained by polymerizing an aromatic carbon atoms 9, indene major monomer, the thermal decomposition of naphtha Specific examples of the C ₉ fraction obtained by styrene include styrene homologues such as α-methylstyrene, β-methylstyrene, and γ-methylstyrene, and indene homologues such as indene and coumarone.
Trade names include Petrogin manufactured by Mitsui Chemicals, Petlite manufactured by Mikuni Chemical, Neopolymer manufactured by JX Nippon Oil & Energy, Petcoal manufactured by Tosoh.

Furthermore, modified petroleum resin modified petroleum resin comprising the C ₉ fraction, as a resin that allows both the grip and factory workability, the present invention is suitably used.
The modified petroleum resins, include C ₉ petroleum resins modified with an unsaturated alicyclic compound, C ₉ petroleum resins modified with a compound having a hydroxyl group, C ₉ petroleum resins modified with unsaturated carboxylic acid compounds and the like It is done.

Preferred unsaturated cycloaliphatic compounds include cyclopentadiene, methylcyclopentadiene, and the like, and Dielspenter reaction products of alkylcyclopentadiene include dicyclopentadiene, cyclopentadiene / methylcyclopentadiene co-dimer, tricyclopentadiene, etc. And dicyclopentadiene is particularly preferable.
Dicyclopentadiene-modified C ₉ petroleum resin in the presence of dicyclopentadiene and C ₉ fraction both can be obtained by thermal polymerization or the like.
The dicyclopentadiene-modified C ₉ petroleum resin include, for example, JX Nippon Oil & Energy Ltd. Neo polymer 130S.

Examples of the compound having a hydroxyl group include alcohol compounds and phenol compounds.
Specific examples of the alcohol compound include alcohol compounds having a double bond such as allyl alcohol and 2-butene-1,4 diol.
As the phenol compound, alkylphenols such as phenol, cresol, xylenol, pt-butylphenol, p-octylphenol, and p-nonylphenol can be used.
These hydroxyl group-containing compounds may be used alone or in combination of two or more.

Hydroxyl group-containing C ₉ petroleum resin, after introducing the ester group in the petroleum resin by thermal polymerization with petroleum distillate (meth) acrylic acid alkyl ester, a method of reducing the ester group, in the petroleum resin two It can also be produced by a method of hydrating the double bond after remaining or introducing the heavy bond.
In the present invention, as the hydroxyl group-containing C ₉ petroleum resin, can be used those obtained by the various methods as, Performance, viewed from the manufacturing aspect, it is preferred to use a phenol-modified petroleum resins, phenol-modified petroleum resins, obtained by cationic polymerization of the C ₉ fraction in the presence of phenol, modified is easy and low cost.
The phenol-modified _{C 9} petroleum resin, for example, JX Nippon Oil & Energy Ltd. Neo polymer -E-130 and the like.

Further, as a modified C ₉ petroleum resin with an unsaturated carboxylic acid compound, it is possible to use those obtained by modifying the C ₉ petroleum resin in an ethylenically unsaturated carboxylic acid.
Typical examples of such ethylenically unsaturated carboxylic acids include (anhydrous) maleic acid, fumaric acid, itaconic acid, tetrahydro (anhydrous) phthalic acid, (meth) acrylic acid or citraconic acid.
Unsaturated carboxylic acid-modified C ₉ petroleum resin can be obtained by thermally polymerizing C ₉ petroleum resin and ethylenically unsaturated carboxylic acid.
In the present invention, maleic acid-modified C ₉ petroleum resin is preferable.
Examples of the unsaturated carboxylic acid-modified C ₉ petroleum resin, for example, JX Nippon Oil & Energy Ltd. Neo polymer 160 and the like.

Further, in the present invention can be suitably used C ₅ fraction and C ₉ fraction copolymer resin obtained by thermal cracking of naphtha.
Examples of the C ₉ fraction is not particularly limited, it is preferably a C ₉ fraction obtained by thermal cracking of naphtha.
Specific examples include Struktol series TS30, TS30-DL, TS35, TS35-DL manufactured by SCHILL & SEILACHER.

  Examples of the phenolic resins include alkylphenol formaldehyde resins and rosin-modified products thereof, alkylphenol acetylene resins, modified alkylphenol resins, terpene phenol resins, and the like. Examples include HITanol 1502 and a trade name BASF CORRECIN, which is a pt-butylphenol acetylene resin.

Coal-based resins include coumarone indene resins and the like, and xylene-based resins include xylene formaldehyde resins and the like.
Other polybutenes can also be used as a resin having tackiness.
Among these synthetic resins, from the viewpoint of abrasion resistance and grip performance of formulated rubber composition, C ₅ fraction and C ₉ fraction copolymer resin, a C ₉ fraction (co) polymerized The obtained aromatic petroleum resin, phenolic resin and coumarone indene resin are preferred.

The resin of component (B) preferably has a softening point of 200 ° C. or less (measurement method: ASTM E28-58-T) or less, and more preferably in the range of 80 to 150 ° C.
When the softening point exceeds 200 ° C., the temperature dependence of the hysteresis loss characteristic may become too high, and the workability may be deteriorated. Moreover, if it is less than 80 degreeC, grip performance may be inferior.
From these viewpoints, the softening point is more preferably in the range of 90 to 120 ° C.
The above resins may be used alone or in combination of two or more.
(C) 5-60 mass parts with respect to 100 mass parts of rubber components, Preferably 10-20 mass parts is mix | blended.

  The rubber composition of the present invention may contain (D) a softening agent such as process oil for the purpose of improving physical properties. Examples of oils that can be used include paraffinic, naphthenic and aromatic oils. Aromatics are used for applications that emphasize tensile strength and wear resistance, and naphthenic or paraffinic systems are used for applications that emphasize hysteresis loss and low-temperature characteristics. The amount used is preferably 10 to 135 parts by mass with respect to 100 parts by mass of the rubber component, and if it is 10 parts by mass or more, the tensile strength and low heat build-up of the vulcanized rubber will be good.

In the rubber composition of the present invention, various chemicals usually used in the rubber industry as desired, for example, a vulcanizing agent, a vulcanization accelerator, an anti-aging agent, an anti-scorch agent, as long as the object of the present invention is not impaired. Zinc white, stearic acid and the like can be contained.
Sulfur etc. are mentioned as a vulcanizing agent, The usage-amount is 0.1-10.0 mass parts as a sulfur content with respect to 100 mass parts of rubber components, 0.5-5.0 mass parts is preferable. More preferred.
The vulcanization accelerator is not particularly limited. For example, M (2-mercaptobenzothiazole), DM (dibenzothiazyl disulfide), CZ (N-cyclohexyl-2-benzothiazylsulfenamide), etc. And guanidine-based vulcanization accelerators such as DPG (diphenylguanidine) can be used, and the amount used is preferably 0.1 to 5.0 parts by mass with respect to 100 parts by mass of the rubber component. More preferably, it is 0.2 to 3.0 parts by mass.

  The rubber composition of the present invention is obtained by kneading a rubber component and a resin, and other components appropriately selected as necessary, using a kneading machine such as a Banbury mixer, a roll, an internal mixer, and the like. After that, it is vulcanized and used as a tire tread for tire use. As vulcanization conditions, the temperature is about 100 to 190 ° C.

  The pneumatic tire of the present invention is produced by a usual method using the above rubber composition as a tread. That is, if necessary, the rubber composition of the present invention containing various chemicals as described above is processed into a tire tread at an unvulcanized stage, and pasted and molded by a normal method on a tire molding machine, A green tire is formed. The green tire is heated and pressed in a vulcanizer to obtain a tire. The pneumatic tire thus obtained has excellent grip performance and excellent wear resistance, and is suitable as an all-season tire or the like.

EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited at all by these examples.
The physical properties of the vulcanized rubber of the rubber composition obtained in each example were measured according to the following methods.

(1) Abrasion resistance The pneumatic tire according to the comparative example and the example was mounted on a vehicle, and the amount of wear was calculated from the measurement of the remaining groove after traveling 100,000 km. The result was calculated as travel distance / (groove depth before travel−groove depth after travel), and the result of Comparative Example 1 was taken as 100 and displayed as an index. It shows that it is excellent in abrasion resistance, so that a numerical value is large.

(2) Limit grip Pneumatic tires according to comparative examples and examples were mounted on a vehicle, and the lap time was measured on a test course. The result was expressed as an index with the result of Comparative Example 1 being 100. The larger the value, the better the grip.

Production Example 1
Manufacture of modified polybutadiene (modified BR) (1) Preparation of catalyst 7.11 g of cyclohexane solution of butadiene (15.2% by weight) in the following order in a glass bottle with a volume of about 100 ml with a rubber stopper that was dried and nitrogen-substituted. , 0.59 ml of a neodymium neodecanoate cyclohexane solution (0.56M), 10.32 ml of a toluene solution of aluminum aluminoxane MAO (PMAO manufactured by Tosoh Akzo) (aluminum concentration: 3.23M), diisobutylaluminum hydride (manufactured by Kanto Chemical) ) In hexane solution (0.90M) was added and aged at room temperature for 2 minutes, and then 1.45 ml of hexane solution (0.95M) in chlorinated diethylaluminum (manufactured by Kanto Chemical) was added at room temperature. Aged for 15 minutes with occasional stirring. The concentration of neodymium in the catalyst solution thus obtained was 0.011 M (mol / liter).

(2) Production of intermediate polymer Into a glass bottle with a volume of about 900 ml with a rubber stopper, which was dried and nitrogen-substituted, a dry-purified 1,3-butadiene cyclohexane solution and dry cyclohexane were charged, respectively. 400 g of a 12.5% by mass cyclohexane solution was charged. Next, 2.28 ml (0.025 mmol in terms of neodymium) of the catalyst solution prepared in (1) was added, and polymerization was performed in a 50 ° C. warm water bath for 1.0 hour to produce an intermediate polymer. The resulting polymer had a microstructure of cis-1,4-bond 95.5%, trans-1,4-bond content 3.9% and vinyl bond content 0.6%. These microstructures were determined by Fourier transform infrared spectroscopy (FT-IR).

(3) Primary denaturation treatment As the primary denaturing agent, GPMOS becomes 23.5 molar equivalents to neodymium as a hexane solution (1.0 M) of 3-glycidoxypropyltrimethoxysilane (GPMOS). The first modification was carried out by charging the polymer solution obtained in (2) and treating at 50 ° C. for 60 minutes.

(4) Treatment after secondary modification Subsequently, 1.76 ml (equivalent to 70.5 eq / Nd) of a cyclohexane solution (1.01 M) of bis (2-ethylhexanoate) tin (BEHAS) as a condensation accelerator. ) And 32 μl of ion-exchanged water (equivalent to 70.5 eq / Nd) were added and treated in a hot water bath at 50 ° C. for 1.0 hour. Thereafter, 2 ml of an isopropanol 5% solution of the antioxidant 2,2-methylene-bis (4-ethyl-6-tert-butylphenol) (NS-5) was added to the polymerization system to stop the reaction, and a trace amount of NS The modified BR was obtained by reprecipitation in isopropanol containing -5 and drum drying. It was 93 when Mooney viscosity ML1 _{+ 4} (100 degreeC) of obtained BR was measured at 100 degreeC using the RLM-01 type | mold tester by Toyo Seiki Seisakusho. The microstructure after modification was similar to that of the intermediate polymer.

Examples 1-13 and Comparative Examples 1-16
A rubber composition having the composition shown in Table 1 was prepared, and each rubber composition was disposed on a tread of a pneumatic tire for a passenger car having a tire size of 195 / 60R15, and a tire was manufactured as a trial. The performance evaluation results of each tire are shown in Tables 1-3.

Note (Tables 1-3)
1) Natural rubber 2) Styrene-butadiene copolymer rubber: “SBR 1500” manufactured by JSR Corporation
3) Polybutadiene rubber: “BR01” manufactured by JSR Corporation
4) Modified polybutadiene of Production Example 1 5) “A / OMIX” manufactured by Sankyo Oil Chemical Co., Ltd.
6) Resin: “ECR-213” manufactured by Tonen Chemical Co., Ltd.
7) “AQ” manufactured by Tosoh Silica Corporation
8) "Seast 6" made by ISAF (N220), Tokai Carbon Co., Ltd.
9) Degussa “Si69”
10) Wax: “Sangite” by Seiko Kagaku
11) N- (1,3-dimethylbutyl) -N′-phenyl-p-phenylenediamine: “NOCRACK 6C” manufactured by Ouchi Shinsei Chemical Co., Ltd.
12) Diphenylguanidine: "Noxeller D" manufactured by Ouchi Shinsei Chemical Co., Ltd.
13) N-cyclohexyl-2-benzothiazylsulfenamide: “Noxeller CZ” manufactured by Ouchi Shinsei Chemical Co., Ltd.
14) Dibenzothiazyl disulfide: “Noxeller DM” manufactured by Ouchi Shinsei Chemical Industry Co., Ltd.

  As can be seen from Tables 1 to 3, the compositions of the examples are more resistant to abrasion than those using no modified BR, those using BR instead of the modified BR, and those obtained by replacing the resin with oil. The properties and grip performance are better in balance than the composition of the comparative example. Further, the composition of Example 2 is an example in which the modified BR is reduced and the SBR is large, and although the wear resistance is lowered, the grip performance is greatly improved. Examples 3 to 5 are compositions prepared by changing the resin instead of oil, but it is understood that these all have high wear resistance and grip performance. Examples 6-8 Although the amount of resin and oil was changed, wear resistance and grip performance were improved in a well-balanced manner when the resin was used compared to the comparative example. Examples 10 to 13 are cases in which natural rubber is not included, but both wear resistance and grip performance are greatly improved by using resins and fillers within the scope of the present invention.

  The rubber composition for a tire tread of the present invention has excellent grip performance and wear resistance, and is suitably used for, for example, all-season tires.

Claims (14)

  (A) (A-1) Modified conjugated diene polymer 5 obtained by modifying the active terminal of a conjugated diene polymer having a cis-1,4-bond content of 75 mol% or more with at least a hydrocarbyloxysilane compound To (B-2) (B-1) 50 to 95 mass% and (B-2) (B-2) silica component and 100 mass parts of rubber component containing (A-2) natural rubber and / or diene synthetic rubber B-2) A rubber composition for a tire tread comprising 60 to 140 parts by mass of a reinforcing filler composed of 50 to 5% by mass of carbon black and (C) 5 to 60 parts by mass of a resin.   The rubber composition for a tire tread according to claim 1, wherein 10 parts by weight of (D) oil is further added to 100 parts by weight of the rubber component (A).   The rubber composition for tire treads according to claim 1 or 2, comprising (E) a silane coupling agent in a proportion of 5 to 20% by mass relative to silica of component (B-1).   (A) The rubber composition for tire treads in any one of Claims 1-3 containing 5-30 mass parts of inorganic fillers with respect to 100 mass parts of rubber components.   The modified conjugated diene polymer of component (A-1) is obtained by subjecting the active end to primary modification with a hydrocarbyloxysilane compound and then secondary modification with a hydrocarbyloxysilane compound in the presence of a condensation accelerator. The rubber composition for a tire tread according to any one of claims 1 to 4.   The modified conjugated diene polymer of component (A-1) is obtained by first reacting the active terminal with a hydrocarbyloxysilane compound and then further reacting with a carboxylic acid partial ester of a polyhydric alcohol. 5. The rubber composition for a tire tread according to any one of 4 above.   The modified conjugated diene polymer of the component (A-1) has a hydrocarbyloxysilane compound residue which is introduced into the terminal after the primary modification of the active terminal with the hydrocarbyloxysilane compound and further in the presence of a condensation accelerator. The rubber composition for a tire tread according to any one of claims 1 to 4, wherein the rubber composition is formed by a condensation reaction with a reactive hydrocarbyloxysilane compound.   The rubber composition for a tire tread according to claim 5, wherein the modified conjugated diene polymer of the component (A-1) is further reacted with a carboxylic acid partial ester of a polyhydric alcohol after the secondary modification. .   The rubber composition for a tire tread according to claim 7, wherein the modified conjugated diene polymer of the component (A-1) is further reacted with a carboxylic acid partial ester of a polyhydric alcohol after the condensation reaction. The hydrocarbyloxysilane compound is at least one compound selected from compounds represented by the following general formulas (I), (II), and (III) and partial condensates thereof: Rubber composition for tire tread.
Formula (I)

[Wherein A ¹ is (thio) epoxy, (thio) isocyanate, (thio) ketone, (thio) aldehyde, imine, amide, isocyanuric acid trihydrocarbyl ester, (thio) carboxylic acid ester, (thio) carboxylic acid A monovalent group having at least one functional group selected from a metal salt, a carboxylic acid anhydride, a carboxylic acid halide, and a dihydrocarbyl carbonate ester, R ¹ is a single bond or a divalent inert hydrocarbon group , R ² and R ³ each independently represent a monovalent aliphatic hydrocarbon group having 1 to 20 carbon atoms or a monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms, and n is an integer of 0 to 2 , and the case where R ² is plural, R ² may be the same or different, if the OR ³ there are a plurality, the plurality of OR ³ may be the same or different, and in the molecule active Proton and onium salt are not included]
Formula (II)

Wherein, A ² is a cyclic tertiary amine, acyclic tertiary amine, pyridine, monovalent group having at least one functional group selected from among sulfides and multi sulfide, R ⁴ is an aliphatic hydrocarbon Group or aromatic hydrocarbon group, R ⁵ and R ⁶ 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, m is an integer of 0 to 2, if R ⁵ there are a plurality, the plurality of R ⁵ may be the same or different, if OR ⁶ there are plural, a plurality of OR ⁶ may be the same or different, The molecule does not contain active protons and onium salts. ]
Formula (III)

[Wherein A ³ represents alcohol, thiol, primary amine and onium salt thereof, cyclic secondary amine and onium salt thereof, acyclic secondary amine and onium salt thereof, onium salt of cyclic tertiary amine, acyclic tertiary amine An onium salt of an amine, a group having an aryl or arylalkyl Sn bond, a monovalent group having at least one functional group selected from sulfonyl, sulfinyl and nitrile, R ⁷ is an aliphatic hydrocarbon group or an aromatic hydrocarbon group , R ⁸ and R ⁹ each independently represent a monovalent aliphatic hydrocarbon group having 1 to 20 carbon atoms or a monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms, q is an integer of 0 to 2 , and the case where R ⁸ is plural, R ⁸ may be the same or different, if the OR ⁹ there are a plurality, the plurality of OR ⁹ may be the same or different. ]   The rubber composition for a tire tread according to any one of claims 6, 8 and 9, wherein the carboxylic acid partial ester of the polyhydric alcohol is a monoester, diester or triester of sorbitan fatty acid. The condensation accelerator comprises at least one selected from compounds represented by the following general formula (IV), general formula (V) and general formula (VI) and water: The rubber composition for a tire tread as described.
Formula (IV)
Sn (OCOR ¹⁰ ) ₂ .... (IV)
[Wherein R ¹⁰ is an alkyl group having 2 to 19 carbon atoms, and when there are a plurality of them, they may be the same or different.]
A carboxylate having 3 to 20 carbon atoms of tin having an oxidation number of 2 represented by:
General formula (V)
R ¹¹ _r SnA ⁴ _t B ¹ _(4- tr ₎ (V)
[Wherein, r is an integer of 1 to 3, t is an integer of 1 or 2, and t + r is an integer of 3 or 4. R ¹¹ is an aliphatic hydrocarbon group having 1 to 30 carbon atoms, and B ¹ is a hydroxyl group or a halogen. A ⁴ represents (a) an aliphatic carboxylic acid residue having 2 to 30 carbon atoms, (b) a 1,3-dicarbonyl-containing group having 5 to 30 carbon atoms, and (c) a hydrocarbyloxy group having 3 to 30 carbon atoms. And (d) a group selected from a siloxy group having a total of three substitutions (which may be the same or different) with a hydrocarbyl group having 1 to 20 carbon atoms and / or a hydrocarbyloxy group having 1 to 20 carbon atoms, and R ¹¹ may if there are multiple the same or different, may be the same or different if A ⁴ is more]
A tin compound with an oxidation number of 4 represented by:
Formula (VI)
A ⁵ _x TiB ² _(4-x) (VI)
[Wherein x is an integer of 2 or 4. A ⁵ is (1) a C 3-30 hydrocarbyloxy group, (2) a C 1-30 alkyl group and / or a C 1-20 hydrocarbyloxy group, which is a total of three substituted siloxy groups, If the A ⁵ there are a plurality may be the same or different. B ² is a 1,3-dicarbonyl-containing group having 5 to 30 carbon atoms, and when there are a plurality of B ² , they may be the same or different.
The titanium compound of oxidation number 4 represented by these.   The rubber composition for a tire tread according to any one of claims 1 to 12, wherein the modified conjugated diene polymer of the component (A-1) is a modified polybutadiene.   The pneumatic tire which used the rubber composition for tire treads in any one of Claims 1-13 for tread rubber.