JP2011099026A - Rubber composition and tire using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rubber composition capable of enhancing wear resistance and wet grip performance while reducing rolling resistance. <P>SOLUTION: The rubber composition is selected from an aromatic vinyl compound-conjugated diene compound copolymer and a rubber component such as a natural rubber. The aromatic vinyl compound-conjugated diene compound copolymer is obtained by addition polymerization of an aromatic vinyl compound and a conjugated compound in the presence of a polymerization catalyst composition containing at least one specified metallocene complex selected from a metallocene complex and the like represented by general formula (I) (wherein, M denotes a lanthanoid element, scandium or yttrium, Cp<SP>R</SP>s each independently denotes a non-substituted or substituted indenyl, R<SP>a</SP>to R<SP>f</SP>each independently denotes a 1C-3C alkyl group, L denotes a neutral Lewis base and w denotes an integer of 0 to 3) and has ≥80% cis-1,4 bonding amount in a conjugated diene compound part. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a rubber composition and a tire using the same, and more particularly to a rubber composition that can be used for a tire member to improve wear resistance and wet grip performance while reducing rolling resistance. Is.

  Recently, in order to improve the safety of a vehicle on a wet road surface, it is required to improve the wet grip performance of a tire. In response to this demand, tires have so far been (1) a rubber composition containing silica instead of carbon black, which is widely used as a reinforcing filler, and (2) a rubber composition containing butyl rubber as a rubber component. The method used for a tread member has been taken.

  However, (1) when using a rubber composition containing silica, there is a problem of shrinkage of unvulcanized rubber, so the processability is poor, and silica is poor in dispersibility compared to carbon black, When the tread member is used, there is a problem that the wear resistance of the tread is lowered. Moreover, when the rubber composition containing (2) butyl rubber is used, the compatibility is deteriorated and bleed is generated, so that the function of the tread is lowered.

  On the other hand, conjugated diene compound polymers such as natural rubber, polyisoprene rubber and polybutadiene rubber have excellent physical properties and are widely used as rubber components for tire members, but generally have a low glass transition temperature. It is known that a rubber composition containing a rubber component as a main component has a low tan δ at 0 ° C., and when used for a tread member of a tire, the wet grip performance of the tire is lowered.

  An aromatic vinyl compound-conjugated diene compound copolymer such as a styrene-butadiene copolymer is also widely used as a rubber component of a tire member because it is excellent in wear resistance and the like, but the isomeric structure of the conjugated diene compound portion. However, it is difficult to control the structure other than the vinyl bond amount, and a technique for controlling the stereoregularity of the conjugated diene compound portion is required in order to impart more excellent performance to the tire.

  On the other hand, in order to control the stereoregularity of the conjugated diene compound portion, for example, the content of the cis-1,4 structure, an aromatic vinyl compound-conjugated using a metal catalyst composed of a ligand and a metal atom. A technique for producing a diene compound copolymer is known (for example, see Patent Documents 1 to 3). However, the aromatic vinyl compound-conjugated diene compound copolymer obtained by this method sometimes involves problems such as blocking of the aromatic vinyl compound portion and lowering of the molecular weight.

Japanese Patent No. 3207502 JP 2006-137897 A Japanese Patent No. 3738315

  Under such circumstances, the present inventors examined the stereoregularity of the conjugated diene compound portion of the aromatic vinyl compound-conjugated diene compound copolymer. As a result, the conjugated diene compound portion has a high cis-1,4 bond content. It can be seen that the aromatic vinyl compound-conjugated diene compound copolymer tends to impart more wear resistance and wet grip performance to the tire than the aromatic vinyl compound-conjugated diene compound copolymer containing a lot of other microstructures. It was.

  Accordingly, an object of the present invention is to solve the above-mentioned problems of the prior art, and to use for a tire member, a rubber composition capable of improving wear resistance and wet grip performance while reducing rolling resistance, and The object is to provide a tire using the rubber composition.

  As a result of intensive studies to achieve the above object, the present inventor has carried out addition polymerization of an aromatic vinyl compound and a conjugated diene compound in the presence of a polymerization catalyst composition containing a specific metallocene complex, thereby producing a conjugated diene compound moiety. An aromatic vinyl compound-conjugated diene compound copolymer having a cis-1,4 bond content of 80% or more is obtained, and the aromatic vinyl compound-conjugated diene compound copolymer is converted into natural rubber, polyisoprene rubber and polybutadiene. It has been found that by applying a rubber composition in combination with at least one selected from the group consisting of rubber to tire members, the wear resistance and wet grip performance can be significantly improved while reducing rolling resistance. The invention has been completed.

（式中、Ｍは、ランタノイド元素、スカンジウム又はイットリウムを示し、Ｃｐ^Rは、それぞれ独立して無置換もしくは置換インデニルを示し、Ｒ^a〜Ｒ^fは、それぞれ独立して炭素数１〜３のアルキル基を示し、Ｌは、中性ルイス塩基を示し、ｗは、０〜３の整数を示す）で表されるメタロセン錯体、及び下記一般式(II)：

（式中、Ｍは、ランタノイド元素、スカンジウム又はイットリウムを示し、Ｃｐ^Rは、それぞれ独立して無置換もしくは置換インデニルを示し、Ｘ'は、水素原子、ハロゲン原子、アルコキシド基、チオラート基、アミド基、シリル基又は炭素数１〜２０の炭化水素基を示し、Ｌは、中性ルイス塩基を示し、ｗは、０〜３の整数を示す）で表されるメタロセン錯体、並びに下記一般式(III)：

（式中、Ｍは、ランタノイド元素、スカンジウム又はイットリウムを示し、Ｃｐ^R'は、無置換もしくは置換シクロペンタジエニル、インデニル又はフルオレニルを示し、Ｘは、水素原子、ハロゲン原子、アルコキシド基、チオラート基、アミド基、シリル基又は炭素数１〜２０の炭化水素基を示し、Ｌは、中性ルイス塩基を示し、ｗは、０〜３の整数を示し、[Ｂ]⁻は、非配位性アニオンを示す）で表されるハーフメタロセンカチオン錯体からなる群より選択される少なくとも１種類の錯体を含む重合触媒組成物の存在下、芳香族ビニル化合物及び共役ジエン化合物を付加重合して得られた、共役ジエン化合物部分のシス-１,４結合量が80％以上の芳香族ビニル化合物−共役ジエン化合物共重合体と、天然ゴム、ポリイソプレンゴム及びポリブタジエンゴムからなる群から選択される少なくとも１種類とをゴム成分として含むことを特徴とする。 That is, the rubber composition of the present invention has the following general formula (I):

(In the formula, M represents a lanthanoid element, scandium or yttrium, Cp ^R independently represents unsubstituted or substituted indenyl, and R ^{a to} R ^f each independently represents an alkyl having 1 to 3 carbon atoms. And L represents a neutral Lewis base, and w represents an integer of 0 to 3), and the following general formula (II):

(In the formula, M represents a lanthanoid element, scandium or yttrium, Cp ^R each independently represents an unsubstituted or substituted indenyl group, and X ′ represents a hydrogen atom, a halogen atom, an alkoxide group, a thiolate group, an amide group. , A silyl group or a hydrocarbon group having 1 to 20 carbon atoms, L represents a neutral Lewis base, w represents an integer of 0 to 3, and the following general formula (III ):

(In the formula, M represents a lanthanoid element, scandium or yttrium, Cp ^R ′ represents an unsubstituted or substituted cyclopentadienyl, indenyl or fluorenyl, and X represents a hydrogen atom, a halogen atom, an alkoxide group or a thiolate group. represents an amide group, a silyl group or a hydrocarbon group having a carbon number of 1 to 20, L is a neutral Lewis base, w is, an integer of 0 to 3, [B] ^- is a non-coordinating Obtained by addition polymerization of an aromatic vinyl compound and a conjugated diene compound in the presence of a polymerization catalyst composition containing at least one complex selected from the group consisting of a half metallocene cation complex represented by , Aromatic vinyl compound-conjugated diene compound copolymer having a cis-1,4 bond amount of 80% or more in the conjugated diene compound portion, natural rubber, polyisoprene rubber and poly And at least one selected from the group consisting of Tajiengomu, characterized in that it comprises as a rubber component.

  Here, the metallocene complex is a complex compound in which one or more cyclopentadienyl or a derivative thereof is bonded to a central metal, and in particular, one cyclopentadienyl or a derivative thereof bonded to the central metal. A certain metallocene complex may be called a half metallocene complex.

  In a preferred example of the rubber composition of the present invention, the hydrogenated resin is further contained in an amount of 0.5 to 100 parts by mass with respect to 100 parts by mass of the rubber component.

  Here, the difference in SP value between the rubber component and the hydrogenated resin is preferably 1.5 or less. The SP value of the rubber component and the (hydrogenated) resin can be calculated according to the Fedors method.

  In the rubber composition of the present invention, the hydrogenated resin is preferably a resin obtained by hydrogenating a petroleum resin or a natural resin, and more preferably a hydrogenated terpene resin obtained by hydrogenating a terpene resin. Here, the hydrogenated terpene resin preferably has a softening point of 80 to 180 ° C.

  In another preferred embodiment of the rubber composition of the present invention, the total content of natural rubber, polyisoprene rubber and polybutadiene rubber in the rubber component is 50% by mass or more.

  In the rubber composition of the present invention, the amount of vinyl bonds in the conjugated diene compound portion is preferably 10% or less.

  In the rubber composition of the present invention, the aromatic vinyl compound-conjugated diene compound copolymer has a block amount in the NMR measurement of the repeating unit of the aromatic vinyl compound portion of 10% or less of the total aromatic vinyl compound portion. Preferably there is.

  In the rubber composition of the present invention, the aromatic vinyl compound-conjugated diene compound copolymer preferably has a melting point (Tm) in DSC measurement.

  In another preferred embodiment of the rubber composition of the present invention, the aromatic vinyl compound-conjugated diene compound copolymer is a styrene-butadiene copolymer.

  The tire of the present invention is characterized by using the above rubber composition in any of tire members, and the tire member is preferably a tread.

  The method for producing the aromatic vinyl compound-conjugated diene compound copolymer includes the metallocene complex represented by the general formula (I) and the general formula (II), and the half represented by the general formula (III). It includes a step of subjecting an aromatic vinyl compound and a conjugated diene compound to addition polymerization in the presence of a polymerization catalyst composition containing at least one complex selected from the group consisting of metallocene cation complexes.

  According to the present invention, the amount of cis-1,4 bonds in the conjugated diene compound portion obtained by addition polymerization of an aromatic vinyl compound and a conjugated diene compound in the presence of a polymerization catalyst composition containing a specific metallocene complex is 80. % Or more of the aromatic vinyl compound-conjugated diene compound copolymer is combined with at least one selected from the group consisting of natural rubber, polyisoprene rubber and polybutadiene rubber. It is possible to provide a rubber composition capable of improving wear resistance and wet grip performance while lowering, and a tire using the rubber composition.

  The present invention is described in detail below. The rubber composition of the present invention is selected from the group consisting of the metallocene complexes represented by the above general formula (I) and the above general formula (II) and the half metallocene cation complex represented by the above general formula (III). Fragrance having 80% or more of cis-1,4 bonds in the conjugated diene compound portion obtained by addition polymerization of an aromatic vinyl compound and a conjugated diene compound in the presence of a polymerization catalyst composition containing at least one complex. The rubber component includes a vinyl group-conjugated diene compound copolymer and at least one selected from the group consisting of natural rubber, polyisoprene rubber and polybutadiene rubber.

The aromatic vinyl compound-conjugated diene compound copolymer used as the rubber component of the rubber composition of the present invention has a very high cis-1,4 bond amount in the conjugated diene compound portion, and the aromatic vinyl compound-conjugated diene compound. A rubber composition using a copolymer as a rubber component includes a rubber composition using a conventional aromatic vinyl compound-conjugated diene compound copolymer obtained by anionic polymerization, and a conventional aromatic vinyl compound-conjugated. Abrasion resistance while maintaining high wet grip performance compared to rubber compositions using a blend of a diene compound copolymer and a homopolymer of a conjugated diene compound having a high cis-1,4 bond content. Can be improved. The reason for this is not necessarily clear, but it seems to be due to the effect of improving the wear resistance due to the crystallinity derived from the amount of cis-1,4 bonds in the conjugated diene compound portion. Here, the amount of cis-1,4 bonds in the conjugated diene compound portion needs to be 80% or more, and preferably 90% or more. When the amount of cis-1,4 bonds in the conjugated diene compound portion is less than 80%, the cis chain is insufficient, so the melting point (Tm) is not measured, and the wear resistance decreases. The amount of cis-1,4 bonds in the conjugated diene compound portion can be determined from the integration ratio of ¹ H-NMR spectrum and ¹³ C-NMR spectrum, and the specific method is disclosed in JP-A-2004-27179. It is disclosed.

  In the aromatic vinyl compound-conjugated diene compound copolymer, the vinyl bond content of the conjugated diene compound portion is preferably 10% or less, and more preferably 5% or less. When the vinyl bond amount in the conjugated diene compound portion exceeds 10%, the cis-1,4 bond amount is lowered and the effect of improving the wear resistance cannot be sufficiently obtained.

  The aromatic vinyl compound-conjugated diene compound copolymer is not particularly limited except that a polymerization catalyst composition described in detail later is used. For example, a method for producing an addition polymer using a normal coordination ion polymerization catalyst In the same manner as above, a mixture of a monomeric aromatic vinyl compound and a conjugated diene compound can be copolymerized. As a polymerization method, any method such as a solution polymerization method, a suspension polymerization method, a liquid phase bulk polymerization method, an emulsion polymerization method, a gas phase polymerization method, and a solid phase polymerization method can be used. When a solvent is used for the polymerization reaction, the solvent used may be inactive in the polymerization reaction, and the amount of the solvent used is arbitrary, but the concentration of the complex contained in the polymerization catalyst composition is 0.1 to 0.0001 mol. The amount is preferably / l. Here, examples of the aromatic vinyl compound include styrene, p-methylstyrene, m-methylstyrene, p-tert-butylstyrene, α-methylstyrene, chloromethylstyrene, vinyltoluene and the like. Among these, styrene Is preferred. On the other hand, examples of the conjugated diene compound include 1,3-butadiene, isoprene, 1,3-pentadiene, 2,3-dimethylbutadiene, and among these, 1,3-butadiene is preferable. Accordingly, a styrene-butadiene copolymer is particularly preferable as the aromatic vinyl compound-conjugated diene compound copolymer.

  The polymerization catalyst composition used for the synthesis of the aromatic vinyl compound-conjugated diene compound copolymer is represented by the metallocene complex represented by the general formulas (I) and (II), and the general formula (III). It is necessary to contain at least one complex selected from the group consisting of half metallocene cation complexes, and further contain other components such as a cocatalyst contained in a polymerization catalyst composition containing a normal metallocene complex. Is preferred.

In the metallocene complexes represented by the above general formulas (I) and (II), Cp ^R in the formula is unsubstituted indenyl or substituted indenyl. Cp ^R having an indenyl ring as a basic skeleton can be represented by C ₉ H _7-X R _X or C ₉ H _11-X R _X. Here, X is an integer of 0-7 or 0-11. In addition, each R is preferably independently a hydrocarbyl group or a metalloid group. The hydrocarbyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, and still more preferably 1 to 8 carbon atoms. Specific examples of the hydrocarbyl group include a methyl group, an ethyl group, a phenyl group, and a benzyl group. On the other hand, examples of metalloid group metalloids include germyl Ge, stannyl Sn, and silyl Si, and the metalloid group preferably has a hydrocarbyl group, and the hydrocarbyl group that the metalloid group has is the same as the above hydrocarbyl group. is there. Specific examples of the metalloid group include a trimethylsilyl group. Specific examples of the substituted indenyl include 2-phenylindenyl, 2-methylindenyl and the like. In addition, two Cp ^R in the general formula (I) and the formula (II) may be the same or different from each other.

（式中、Ｒは水素原子、メチル基又はエチル基を示す。） In the half metallocene cation complex represented by the general formula (III), Cp ^R ′ in the formula is unsubstituted or substituted cyclopentadienyl, indenyl or fluorenyl, and among these, unsubstituted or substituted indenyl It is preferable that Cp ^R ′ having a cyclopentadienyl ring as a basic skeleton is represented by C ₅ H _5-X R _X. Here, X is an integer of 0-5. Moreover, it is preferable that R is respectively independently a hydrocarbyl group; metalloid group. The hydrocarbyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, and still more preferably 1 to 8 carbon atoms. Specific examples of the hydrocarbyl group include a methyl group, an ethyl group, a phenyl group, and a benzyl group. On the other hand, examples of metalloid group metalloids include germyl Ge, stannyl Sn, and silyl Si, and the metalloid group preferably has a hydrocarbyl group, and the hydrocarbyl group that the metalloid group has is the same as the above hydrocarbyl group. is there. Specific examples of the metalloid group include a trimethylsilyl group. Specific examples of Cp ^R 'having a cyclopentadienyl ring as a basic skeleton include the following.

(In the formula, R represents a hydrogen atom, a methyl group or an ethyl group.)

In the general formula (III), Cp ^R ′ having the indenyl ring as a basic skeleton is defined in the same manner as Cp ^{R in the} general formula (I), and preferred examples thereof are also the same.

In the general formula (III), Cp ^R ′ having the fluorenyl ring as a basic skeleton can be represented by C ₁₃ H _9-X R _X or C ₁₃ H _17-X R _X. Here, X is an integer of 0-9 or 0-17. Moreover, it is preferable that R is respectively independently a hydrocarbyl group; metalloid group. The hydrocarbyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, and still more preferably 1 to 8 carbon atoms. Specific examples of the hydrocarbyl group include a methyl group, an ethyl group, a phenyl group, and a benzyl group. On the other hand, examples of metalloid group metalloids include germyl Ge, stannyl Sn, and silyl Si, and the metalloid group preferably has a hydrocarbyl group, and the hydrocarbyl group that the metalloid group has is the same as the above hydrocarbyl group. is there. Specific examples of the metalloid group include a trimethylsilyl group.

  The central metal M in the general formula (I), formula (II) and formula (III) is a lanthanoid element, scandium or yttrium. The lanthanoid elements include 15 elements having atomic numbers 57 to 71, and any of these may be used. Preferred examples of the central metal M include samarium Sm, neodymium Nd, praseodymium Pr, gadolinium Gd, cerium Ce, holmium Ho, scandium Sc, and yttrium Y.

The metallocene complex represented by the general formula (I) contains a bistrialkylsilylamide ligand [—N (SiR ₃ ) ₂ ]. The alkyl groups R (R ^{a to} R ^f in the general formula (I)) contained in the bistrialkylsilylamide are each independently an alkyl group having 1 to 3 carbon atoms, and is preferably a methyl group.

The metallocene complex represented by the general formula (II) contains a silyl ligand [—SiX ′ ₃ ]. X ′ contained in the silyl ligand [—SiX ′ ₃ ] is a group defined in the same manner as X in the general formula (III) described below, and preferred groups are also the same.

  In the general formula (III), X is a group selected from the group consisting of a hydrogen atom, a halogen atom, an alkoxide group, a thiolate group, an amide group, a silyl group, and a hydrocarbon group having 1 to 20 carbon atoms. Here, examples of the alkoxide group include aliphatic alkoxy groups such as methoxy group, ethoxy group, propoxy group, n-butoxy group, isobutoxy group, sec-butoxy group and tert-butoxy group; phenoxy group and 2,6-di- -tert-butylphenoxy group, 2,6-diisopropylphenoxy group, 2,6-dineopentylphenoxy group, 2-tert-butyl-6-isopropylphenoxy group, 2-tert-butyl-6-neopentylphenoxy group, Examples include aryloxide groups such as 2-isopropyl-6-neopentylphenoxy group, and among these, 2,6-di-tert-butylphenoxy group is preferable.

  In the general formula (III), the thiolate group represented by X includes a thiomethoxy group, a thioethoxy group, a thiopropoxy group, a thio n-butoxy group, a thioisobutoxy group, a thio sec-butoxy group, a thio tert-butoxy group and the like Group thiolate group; thiophenoxy group, 2,6-di-tert-butylthiophenoxy group, 2,6-diisopropylthiophenoxy group, 2,6-dineopentylthiophenoxy group, 2-tert-butyl-6-isopropyl Arylthiolate groups such as thiophenoxy group, 2-tert-butyl-6-thioneopentylphenoxy group, 2-isopropyl-6-thioneopentylphenoxy group, 2,4,6-triisopropylthiophenoxy group, etc. Among these, 2,4,6-triisopropylthiophenoxy group is preferable.

  In the general formula (III), the amide group represented by X includes aliphatic amide groups such as dimethylamide group, diethylamide group and diisopropylamide group; phenylamide group, 2,6-di-tert-butylphenylamide group, 2 2,6-diisopropylphenylamide group, 2,6-dineopentylphenylamide group, 2-tert-butyl-6-isopropylphenylamide group, 2-tert-butyl-6-neopentylphenylamide group, 2-isopropyl- Arylamide groups such as 6-neopentylphenylamide group, 2,4,6-tert-butylphenylamide group; and bistrialkylsilylamide groups such as bistrimethylsilylamide group. Among these, bistrimethylsilylamide group is preferable.

  In the general formula (III), examples of the silyl group represented by X include trimethylsilyl group, tris (trimethylsilyl) silyl group, bis (trimethylsilyl) methylsilyl group, trimethylsilyl (dimethyl) silyl group, triisopropylsilyl (bistrimethylsilyl) silyl group, and the like. Among these, a tris (trimethylsilyl) silyl group is preferable.

  In the general formula (III), the halogen atom represented by X may be a fluorine atom, a chlorine atom, a bromine atom or an iodine atom, but a chlorine atom or a bromine atom is preferred. Specific examples of the hydrocarbon group having 1 to 20 carbon atoms represented by X include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert- Linear or branched aliphatic hydrocarbon groups such as butyl group, neopentyl group, hexyl group, octyl group; aromatic hydrocarbon groups such as phenyl group, tolyl group, naphthyl group; aralkyl groups such as benzyl group, etc. Others: Examples include hydrocarbon groups containing silicon atoms such as trimethylsilylmethyl group and bistrimethylsilylmethyl group. Among these, methyl group, ethyl group, isobutyl group, trimethylsilylmethyl group and the like are preferable.

  In the general formula (III), X is preferably a bistrimethylsilylamide group or a hydrocarbon group having 1 to 20 carbon atoms.

In the general formula (III), [B] ^- The non-coordinating anion represented by, for example, a tetravalent boron anion. Specific examples of the tetravalent boron anion include tetraphenylborate, tetrakis (monofluorophenyl) borate, tetrakis (difluorophenyl) borate, tetrakis (trifluorophenyl) borate, tetrakis (tetrafluorophenyl) borate, tetrakis ( Pentafluorophenyl) borate, tetrakis (tetrafluoromethylphenyl) borate, tetra (tolyl) borate, tetra (xylyl) borate, (triphenyl, pentafluorophenyl) borate, [tris (pentafluorophenyl), phenyl] borate, tri Decahydride-7,8-dicarbaoundecaborate is exemplified, and among these, tetrakis (pentafluorophenyl) borate is preferable.

  The metallocene complex represented by the above general formulas (I) and (II) and the half metallocene cation complex represented by the above general formula (III) are further 0 to 3, preferably 0 to 1 neutral. Contains Lewis base L. Here, examples of the neutral Lewis base L include tetrahydrofuran, diethyl ether, dimethylaniline, trimethylphosphine, lithium chloride, neutral olefins, neutral diolefins, and the like. Here, when the complex includes a plurality of neutral Lewis bases L, the neutral Lewis bases L may be the same or different.

  Further, the metallocene complex represented by the general formula (I) and the formula (II) and the half metallocene cation complex represented by the general formula (III) may exist as a monomer, It may exist as a body or higher multimer.

（式中、Ｘ''はハライドを示す。） The metallocene complex represented by the general formula (I) includes, for example, a lanthanoid trishalide, scandium trishalide, or yttrium trishalide in a solvent, an indenyl salt (for example, potassium salt or lithium salt) and bis (trialkylsilyl). It can be obtained by reacting with an amide salt (for example, potassium salt or lithium salt). In addition, since reaction temperature should just be about room temperature, it can manufacture on mild conditions. The reaction time is arbitrary, but is about several hours to several tens of hours. The reaction solvent is not particularly limited, but is preferably a solvent that dissolves the raw material and the product. For example, toluene may be used. The reaction examples for obtaining the metallocene complex represented by the general formula (I) are shown below.

(In the formula, X ″ represents a halide.)

（式中、Ｘ''はハライドを示す。） The metallocene complex represented by the general formula (II) includes, for example, a lanthanoid trishalide, scandium trishalide or yttrium trishalide in a solvent, an indenyl salt (for example, potassium salt or lithium salt) and a silyl salt (for example, potassium). Salt or lithium salt). In addition, since reaction temperature should just be about room temperature, it can manufacture on mild conditions. The reaction time is arbitrary, but is about several hours to several tens of hours. The reaction solvent is not particularly limited, but is preferably a solvent that dissolves the raw material and the product. For example, toluene may be used. The reaction examples for obtaining the metallocene complex represented by the general formula (II) are shown below.

(In the formula, X ″ represents a halide.)

The half metallocene cation complex represented by the general formula (III) can be obtained, for example, by the following reaction.

Here, in the compound represented by the general formula (IV), M represents a lanthanoid element, scandium or yttrium, and Cp ^R ′ independently represents unsubstituted or substituted cyclopentadienyl, indenyl or fluorenyl. , X represents a hydrogen atom, a halogen atom, an alkoxide group, a thiolate group, an amide group, a silyl group, or a hydrocarbon group having 1 to 20 carbon atoms, L represents a neutral Lewis base, and w represents 0 to 3 Indicates an integer. In the ionic compound represented by the general formula [A] ⁺ [B] ⁻ , [A] ⁺ represents a cation, and [B] ⁻ represents a non-coordinating anion.

Examples of the cation represented by [A] ⁺ include a carbonium cation, an oxonium cation, an amine cation, a phosphonium cation, a cycloheptatrienyl cation, and a ferrocenium cation having a transition metal. Examples of the carbonium cation include trisubstituted carbonium cations such as triphenylcarbonium cation and tri (substituted phenyl) carbonium cation. Examples of the tri (substituted phenyl) carbonyl cation include tri (methylphenyl). ) Carbonium cation and the like. Examples of amine cations include trialkylammonium cations such as trimethylammonium cation, triethylammonium cation, tripropylammonium cation, and tributylammonium cation; N, N-dimethylanilinium cation, N, N-diethylanilinium cation, N, N- N, N-dialkylanilinium cations such as 2,4,6-pentamethylanilinium cation; dialkylammonium cations such as diisopropylammonium cation and dicyclohexylammonium cation. Examples of the phosphonium cation include triarylphosphonium cations such as triphenylphosphonium cation, tri (methylphenyl) phosphonium cation, and tri (dimethylphenyl) phosphonium cation. Among these cations, N, N-dialkylanilinium cation or carbonium cation is preferable, and N, N-dialkylanilinium cation is particularly preferable.

The ionic compound represented by the general formula [A] ⁺ [B] ⁻ used in the above reaction is a compound selected and combined from the above non-coordinating anions and cations, and is an N, N-dimethylaniline. Nitrotetrakis (pentafluorophenyl) borate, triphenylcarbonium tetrakis (pentafluorophenyl) borate and the like are preferable. In general formula [A] ⁺ [B] ^- ionic compounds represented by is preferably added from 0.1 to 10 mol per mol of the metallocene complex, more preferably it added about 1 molar. When the half metallocene cation complex represented by the general formula (III) is used for the polymerization reaction, the half metallocene cation complex represented by the general formula (III) may be provided as it is in the polymerization reaction system, or the compound represented by the general formula (IV) and the general formula used in the reaction [a] ⁺ [B] ^- provides an ionic compound represented separately into the polymerization reaction system, the general formula in the reaction system (III You may form the half metallocene cation complex represented by this. Further, by using a combination of a metallocene complex represented by the general formula (I) or the formula (II) and an ionic compound represented by the general formula [A] ⁺ [B] ⁻ , A half metallocene cation complex represented by the formula (III) can also be formed.

  The structures of the metallocene complexes represented by the general formulas (I) and (II) and the half metallocene cation complex represented by the above general formula (III) are preferably determined by X-ray structural analysis.

  The co-catalyst that can be used in the polymerization catalyst composition can be arbitrarily selected from components used as a co-catalyst for a polymerization catalyst composition containing a normal metallocene complex. Suitable examples of the cocatalyst include aluminoxanes, organoaluminum compounds, and the above ionic compounds. These promoters may be used alone or in combination of two or more.

  The aluminoxane is preferably an alkylaluminoxane, and examples thereof include methylaluminoxane (MAO) and modified methylaluminoxane. As the modified methylaluminoxane, MMAO-3A (manufactured by Tosoh Finechem Co., Ltd.) and the like are preferable. The content of aluminoxane in the polymerization catalyst composition is such that the element ratio Al / M between the central metal M of the metallocene complex and the aluminum element Al of the aluminoxane is about 10 to 1000, preferably about 100. It is preferable.

  On the other hand, examples of the organoaluminum compound include trialkylaluminum, dialkylaluminum chloride, alkylaluminum dichloride, and dialkylaluminum hydride. Among these, trialkylaluminum is preferable. Examples of the trialkylaluminum include triethylaluminum and triisobutylaluminum. In addition, the content of the organoaluminum compound in the polymerization catalyst composition is preferably 1 to 50 times mol, more preferably about 10 times mol for the metallocene complex.

  Furthermore, in the polymerization catalyst composition, each of the metallocene complex represented by the general formula (I) and the formula (II) and the half metallocene cation complex represented by the general formula (III) is used as an appropriate promoter. By combining them, the amount of cis-1,4 bonds and the molecular weight of the resulting copolymer can be increased.

  The method for producing the aromatic vinyl compound-conjugated diene compound copolymer includes the metallocene complex represented by the general formula (I) and the general formula (II), and the half metallocene cation represented by the general formula (III). It includes a step of addition polymerization of an aromatic vinyl compound and a conjugated diene compound in the presence of a polymerization catalyst composition containing at least one kind of complex selected from the group consisting of complexes. Moreover, the said manufacturing method can be made to be the same as that of the manufacturing method of the addition polymer by the addition polymerization reaction using the conventional coordination ion polymerization catalyst except using the polymerization catalyst composition mentioned above as a polymerization catalyst. Here, the production method includes, for example, (1) separately providing the components of the polymerization catalyst composition in a polymerization reaction system containing an aromatic vinyl compound and a conjugated diene compound as monomers, May be a polymerization catalyst composition, or (2) a previously prepared polymerization catalyst composition may be provided in the polymerization reaction system. Moreover, (2) includes providing a metallocene complex (active species) activated by a cocatalyst. In addition, the usage-amount of the metallocene complex contained in a polymerization catalyst composition has the preferable range of 1 / 10000-1 / 100 times mole with respect to a monomer.

  Further, the number average molecular weight (Mn) of the obtained copolymer of the present invention is not particularly limited, and the problem of lowering the molecular weight does not occur. Furthermore, the molecular weight distribution (Mw / Mn) represented by the ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is preferably 3 or less, and more preferably 2 or less. Here, the average molecular weight and the molecular weight distribution can be determined using polystyrene as a standard substance by gel permeation chromatography (GPC).

  The addition polymerization reaction is preferably performed in an atmosphere of an inert gas, preferably nitrogen gas or argon gas.

  The polymerization temperature of the addition polymerization reaction is not particularly limited, but is preferably in the range of −100 ° C. to 200 ° C., for example, and can be about room temperature. When the polymerization temperature is raised, the cis-1,4 selectivity of the polymerization reaction may be lowered. On the other hand, the reaction time of the above addition polymerization reaction is not particularly limited, and is preferably in the range of, for example, 1 second to 10 days, but may be appropriately selected depending on conditions such as the type of monomer to be polymerized, the type of catalyst, and the polymerization temperature. Can do.

In the aromatic vinyl compound-conjugated diene compound copolymer, the block amount in the NMR measurement of the repeating unit of the aromatic vinyl compound portion is preferably 10% or less of the total aromatic vinyl compound portion, % Or less is more preferable, and 0% is particularly preferable. The copolymer obtained using the polymerization catalyst composition tends to polymerize the aromatic vinyl compound at random, and can block the aromatic vinyl compound. Here, the term “random” means that the amount of block in the NMR measurement of the repeating unit of the aromatic vinyl compound portion (hereinafter sometimes referred to as the block aromatic vinyl compound content) is 10% or less of the total aromatic vinyl compound portion. The block refers to an aromatic vinyl compound portion having an aromatic vinyl compound-aromatic vinyl compound bond. If the block aromatic vinyl compound content exceeds 10%, the behavior of the aromatic vinyl compound as a homopolymer appears, the glass transition temperature increases, and the wear resistance may decrease. In addition, a block aromatic vinyl compound content rate can be calculated | required from the integral ratio of a < ¹ > H-NMR spectrum.

  Furthermore, the aromatic vinyl compound-conjugated diene compound copolymer exhibits a melting point (Tm) in DSC measurement (differential scanning calorimetry). Here, the melting point (Tm) in DSC measurement refers to the melting point of a static crystal derived from a chain of conjugated diene compound portions.

  The rubber composition of the present invention further contains at least one selected from the group consisting of natural rubber, polyisoprene rubber and polybutadiene rubber as a rubber component. As described above, conjugated diene compound polymers such as natural rubber, polyisoprene rubber and polybutadiene rubber have excellent physical properties, but generally tend to lower the tan δ at 0 ° C. of the rubber composition, resulting in wet tires. Grip performance may be reduced. However, in the rubber composition of the present invention, the conjugated diene compound polymer is rolled by combining it with an aromatic vinyl compound-conjugated diene compound copolymer having a high cis-1,4 bond amount in the conjugated diene compound portion. It is possible to improve wet grip performance without deteriorating other performance such as resistance.

  Further, the rubber component of the rubber composition of the present invention includes the aromatic vinyl compound-conjugated diene compound copolymer, natural rubber (NR), polyisoprene rubber (IR) and polybutadiene rubber (BR) as necessary. In addition, other synthetic rubbers may be included. Examples of other synthetic rubbers include styrene-butadiene copolymer rubber (SBR) [excluding the above aromatic vinyl compound-conjugated diene compound copolymer], ethylene-propylene-diene rubber. (EPDM), chloroprene rubber (CR), butyl rubber (IIR), halogenated butyl rubber, acrylonitrile-butadiene rubber (NBR) and the like. These rubber components may be used alone or in a blend of two or more.

  Furthermore, the rubber composition of the present invention preferably contains 0.5 parts by mass or more and less than 100 parts by mass of a hydrogenated resin with respect to 100 parts by mass of the rubber component, and if necessary, contains other compounding agents. Can do.

  Generally, by blending a resin, tan δ (loss tangent) near 0 ° C. can be improved and wet grip performance can be improved, but tan δ other than near 0 ° C. also increases at the same time, for example, 50 The tan δ around ℃ also increases. Here, tan δ around 50 ° C is considered as one index of tire rolling resistance. Generally, by using a rubber composition having a high tan δ around 50 ° C as a tread member, the tire rolling resistance increases. End up.

  On the other hand, since the SP value decreases when the resin is hydrogenated, the difference in SP value between the hydrogenated resin and rubber components such as natural rubber, polyisoprene rubber and polybutadiene rubber is higher than that of the resin not hydrogenated. Small. Therefore, the hydrogenated resin is highly compatible with natural rubber, polyisoprene rubber, polybutadiene rubber, and the like. As a result, when hydrogenated resin is compounded, the peak of tanδ becomes sharp, tanδ other than near 0 ° C increases specifically, and tanδ other than near 0 ° C does not increase so much. By using a thing for a tread member of a tire, it becomes possible to further improve wet grip performance, without deteriorating other performances, such as rolling resistance.

  If the amount of hydrogenated resin is less than 0.5 parts by mass with respect to 100 parts by mass of the rubber component, the effect of improving tan δ at 0 ° C is small. On the other hand, at 100 parts by mass or more, since the solubility of the hydrogenated resin in the rubber component is exceeded, the improvement in tan δ at 0 ° C. is small, and the tan δ at 50 ° C. is high. It is because it ends. From these viewpoints, the blending amount of the hydrogenated resin is preferably in the range of 1 to 50 parts by mass with respect to 100 parts by mass of the rubber component.

  In addition, the styrene-butadiene copolymer rubber (SBR) often used in the rubber composition for treads has a difference in SP value from that of the hydrogenated resin, which is not as small as that of natural rubber, polyisoprene rubber and polybutadiene rubber. In the rubber composition whose component is SBR as a main component, the blending effect of the hydrogenated resin is small. Therefore, the rubber composition of the present invention preferably has a total content of natural rubber, polyisoprene rubber and polybutadiene rubber in the rubber component of 50% by mass or more.

  The hydrogenated resin that can be used in the rubber composition of the present invention is a resin obtained by hydrogenating a resin, and preferably a resin obtained by hydrogenating a petroleum resin or a natural resin. Here, the hydrogenation of the resin can be performed by a known method, and a commercially available hydrogenated resin can also be used in the present invention.

  The petroleum resin used as the raw material of the hydrogenated resin is, for example, a cracked oil containing unsaturated hydrocarbons such as olefins and diolefins by-produced together with petrochemical basic raw materials such as ethylene and propylene by thermal decomposition of naphtha of petrochemical industry It is obtained by polymerizing a fraction with a Friedel-Crafts catalyst as a mixture. The petroleum resin is obtained by (co) polymerizing an aliphatic petroleum resin obtained by (co) polymerization of a C5 fraction obtained by thermal decomposition of naphtha, or a C9 fraction obtained by thermal decomposition of naphtha. Aromatic petroleum resins, copolymer petroleum resins obtained by copolymerizing the C5 fraction and C9 fraction, alicyclic compound petroleum resins such as dicyclopentadiene, styrene, substituted styrene, styrene and other Examples thereof include styrene resins such as copolymers with monomers.

  Examples of the natural resin used as the raw material for the hydrogenated resin include terpene resins such as α-pinene-based, β-pinene-based, and dipentene-based terpene resins, aromatic modified terpene resins, and terpene phenol resins.

  As the hydrogenated resin, specifically, Idemitsu Kosan Imabu S100 (trade name, softening point 100 ° C.), Idemitsu Kosan Imabu S110 (trade name, softening point 110 ° C.), Idemitsu Kosan Imabu Y100 (trade name, Imabu Y135 (trade name, softening point 135 ° C), Idemitsu Kosan Imabe P90 (trade name, softening point 90 ° C), Idemitsu Kosan Imabu P100 (trade name, softening point 100 ° C) Idemitsu Kosan Imabu P125 (trade name, softening point 125 ° C), Idemitsu Kosan Imabu P140 (trade name, softening point 140 ° C), Arakawa Chemical Co., Ltd. Alcon P70 (trade name, softening point 70 ° C), Arakawa Chemical Co., Ltd. Alcon P90 (trade name, softening point 90 ° C), Alcon P100 (trade name, softening point 100 ° C), Arakawa Chemical Co., Ltd. Alcon P115 (trade name, softening point 115 ° C), Arakawa Chemical Con P125 (trade name, softening point 125 ° C), Alcon P140 (trade name, softening point 140 ° C) manufactured by Arakawa Chemical Co., Ltd. Alcon SP10 (trade name, softening point 100 ° C) manufactured by Arakawa Chemical Co., Ltd. Alcon M90 manufactured by Arakawa Chemical Co., Ltd. (Trade name, softening point 90 ° C), Arakawa Chemical Co., Ltd. Alcon M100 (trade name, softening point 100 ° C), Arakawa Chemical Co., Ltd. Alcon M115 (trade name, softening point 115 ° C), Arakawa Chemical Co., Ltd. Alcon M135 (product) Name, softening point 135 ° C), Alcon SM10 manufactured by Arakawa Chemical Co., Ltd. (trade name, softening point 100 ° C), KR1840 manufactured by Arakawa Chemical Co., Ltd. (trade name, softening point 100 ° C), KR1842 manufactured by Arakawa Chemical Co., Ltd. (trade name, softening point) 120 ° C), Maruzaltz H505 (trade name, softening point 105 ° C) by Maruzen Petrochemical, Marcarez H90 (trade name, softening point 90 ° C) by Maruzen Petrochemical, Marukaretsu 700F (trade name, softening point 95 ° C) by Maruzen Petrochemical ), Marukaretsu H925 (trade name, softening point 123 ° C) manufactured by Zenzen Petrochemical Co., Ltd. Marcarez H970 (trade name, softening point 175 ° C) manufactured by Maruzen Petrochemical Co., Ltd. (Trade name, softening point 115 ° C), Yasuhara Chemical Clearon P125 (trade name, softening point 125 ° C), Yashara Chemical Clearon P135 (trade name, softening point 135 ° C), Yashara Chemical Clearon P150 (trade name, softening point 152 ° C) ), Clearon M105 from Yashara Chemical (trade name, softening point 105 ° C), Clearon M115 from Yashara Chemical (trade name, softening point 115 ° C), Clearon K100 from Yashara Chemical (trade name, softening point 100 ° C), Clearon K110 from Yashara Chemical (product) Name, softening point 110 ℃), Yasuhara Chemi Examples include Cal Clearon K4100 (trade name, softening point 100 ° C.), Yashara Chemical's Clearon K 4090 (trade name, softening point 90 ° C.), and the like. These hydrogenated resins may be used individually by 1 type, and may be used in combination of 2 or more type.

  In the rubber composition of the present invention, the hydrogenated resin is more preferably a hydrogenated terpene resin obtained by hydrogenating a terpene resin, particularly preferably a hydrogenated terpene resin having a softening point of 80 to 180 ° C. Since the hydrogenated terpene resin originally hydrogenates a terpene resin having a low SP value, the SP value is particularly low. Therefore, the hydrogenated terpene resin has a particularly small difference in SP value from rubber components such as natural rubber, polyisoprene rubber, and polybutadiene rubber, and the effect obtained by the hydrogenated resin is remarkable. When a hydrogenated terpene resin having a softening point of less than 80 ° C is used, steering stability tends to deteriorate. On the other hand, when a softened point exceeds 180 ° C, a hydrogenated terpene resin is used at 0 ° C. The effect of improving the tan δ is small, and the tan δ at 50 ° C. becomes high.

  In the rubber composition of the present invention, the difference in SP value between the rubber component and the hydrogenated resin is preferably 1.5 or less. When the difference in SP value between the rubber component and the hydrogenated resin is 1.5 or less, the compatibility between the rubber component and the hydrogenated resin is particularly good, so that the effect obtained by the hydrogenated resin appears significantly, such as rolling resistance. The wet grip performance can be greatly improved without deteriorating other performance.

  The rubber composition of the present invention preferably further contains a filler. Here, the blending amount of the filler is not particularly limited, but is preferably in the range of 10 to 200 parts by mass with respect to 100 parts by mass of the rubber component. If the blending amount of the filler is less than 10 parts by mass, sufficient reinforcement may not be obtained, and if it exceeds 200 parts by mass, the workability may be deteriorated. Here, as the filler, carbon black, silica, alumina, aluminum hydroxide, calcium carbonate, titanium oxide and the like are preferable, and among these, carbon black and / or silica are particularly preferable. The carbon black is preferably GPF, FEF, SRF, HAF, ISAF or SAF grade, more preferably HAF, ISAF or SAF grade. On the other hand, as silica, wet silica and dry silica are preferable, and wet silica is more preferable. These reinforcing fillers may be used alone or in a combination of two or more.

  Further, the rubber composition of the present invention includes, in addition to the rubber component, hydrogenated resin, and reinforcing filler, compounding agents usually used in the rubber industry, such as softeners, anti-aging agents, and coupling agents. A vulcanization accelerator, a vulcanization acceleration aid, a vulcanization agent, and the like can be appropriately selected within a range that does not impair the object of the present invention, and can be blended within a range of a normal blending amount. As these compounding agents, commercially available products can be suitably used. In addition, the rubber composition of this invention can be manufactured by mix | blending the rubber component with the various compounding agents selected suitably as needed, and knead | mixing, heating, and extruding.

  The tire according to the present invention is characterized in that the rubber composition described above is used in any of tire members, and the tire member is preferably a tread. In addition, since the above-described rubber composition is used for the tire of the present invention, the tire of the present invention has sufficient other performance such as rolling resistance, as well as wear resistance and wet grip performance. Especially good. In addition, the tire of this invention can be manufactured by shape | molding a raw tire using the above-mentioned rubber composition in any of a tire member, and vulcanizing | cure a raw tire according to a conventional method. Moreover, as gas with which the tire of the present invention is filled, an inert gas such as nitrogen, argon, helium, etc. can be used in addition to normal or air having an adjusted oxygen partial pressure.

  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.

First, in the production of the polymer B used in Examples 1 and 2, the half metallocene cation complex represented by the general formula (III) used in common was synthesized, and the structure was analyzed by ¹ H-NMR and X-ray crystal. It was confirmed by structural analysis. ¹ H-NMR was measured at room temperature using THF-d8 as a solvent. X-ray crystal structure analysis was performed using RAXIS CS (Rigaku).

<Synthesis Example of [(2-MeC ₉ H ₆ ) GdN (SiMe ₃ ) ₂ (THF) ₃ ] [B (C ₆ F ₅ ) ₄ ]>
Under a nitrogen atmosphere, triethylanilinium tetrakisphenylborate (Et ₃ NHB (C ₆ H ₆ ) ₄ ) was added to 5 mL of a solution of (2-MeC ₉ H ₆ ) ₂ GdN (SiMe ₃ ) ₂ (0.150 g, 0.260 mmol) in THF. (0.110 g, 0.260 mmol) was added and stirred at room temperature for 12 hours. Thereafter, THF was distilled off under reduced pressure, and the resulting residue was washed three times with hexane to obtain an oily compound. The residue was recrystallized with a THF / hexane mixed solvent to produce [(2-MeC ₉ H ₆ ) GdN (SiMe ₃ ) ₂ (THF) ₃ ] [B (C ₆ F ₅ ) ₄ ] (150 mg as white crystals). 59%). The structure was confirmed by X-ray crystal analysis.

<Production example of polymer B>
In a glove box under a nitrogen atmosphere, 104 g (1 mol) of styrene and 50 g of toluene were added to a well-dried 1 L pressure-resistant glass bottle, and the bottle was stoppered. Thereafter, the bottle was taken out from the glove box, and 54 g (1 mol) of 1,3-butadiene was charged to obtain a monomer solution. On the other hand, in a glove box under a nitrogen atmosphere, 40 μmol of bis (2-methylindenyl) gadolinium (trimethylsilylamide) [(2-MeC ₉ H ₆ ) ₂ GdN (SiMe ₃ ) ₂ ] was added to a glass container. ₄₀ μmol of phenylcarbonium tetrakis (pentafluorophenyl) borate (Ph ₃ CB (C ₆ F ₅ ) ₄ ) and 1 mmol of diisobutylaluminum halide were charged and dissolved in 10 ml of toluene to obtain a catalyst solution. Thereafter, the catalyst solution was taken out from the glove box, added to the monomer solution, and polymerized at 70 ° C. for 30 minutes. After the polymerization, the reaction was stopped by adding 10 ml of a 10 mass% methanol solution of 2,6-bis (t-butyl) -4-methylphenol (BHT), and the polymer was separated with a large amount of methanol / hydrochloric acid mixed solvent. And dried in vacuum at 60 ° C. The yield of the obtained polymer was 47 g.

  Regarding the polymer B produced as described above, the number average molecular weight (Mn), molecular weight distribution (Mw / Mn), microstructure, bound styrene content, block styrene content, glass transition point (Tg), melting point (Tm) Was measured by the following method. The results are shown in Table 1. In addition, it shows in Table 1 similarly about the physical property of the polymer A used for Comparative Examples 1-2.

(1) Number average molecular weight (Mn) and molecular weight distribution (Mw / Mn)
Gel permeation chromatography [GPC: Tosoh HLC-8020, column: Tosoh GMH-XL (two in series), detector: differential refractometer (RI)], based on monodisperse polystyrene, The number average molecular weight (Mn) and molecular weight distribution (Mw / Mn) in terms of polystyrene were determined.
(2) Microstructure and amount of bound styrene The microstructure of the polymer was determined from the integration ratio of ¹ H-NMR spectrum and ¹³ C-NMR spectrum, and the amount of bound styrene of the polymer was determined from the integration ratio of ¹ H-NMR spectrum. ¹ HNMR and ¹³ C-NMR were measured at 120 ° C. using 1,1,2,2-tetrachloroethane as a solvent.
(3) Block Styrene Content The ratio of the block amount (block styrene content) in the NMR measurement of the repeating unit of the styrene portion to the total styrene portion was determined from the integration ratio of the ¹ H-NMR spectrum.
(4) Glass transition point (Tg) (° C) and melting point (Tm) (° C)
After weighing 10mg ± 0.5mg of sample, putting it in an aluminum measuring pan and covering it with a DSC device (TA Instruments) from room temperature to 50 ° C and stabilizing for 10 minutes The glass transition point (Tg) and the melting point (Tm) were measured while the temperature was raised to 50 ° C. at a rate of temperature increase of 10 ° C./min.

  From the detailed NMR data of the sample, no styrene-styrene bond was particularly confirmed.

* 1 Styrene-butadiene copolymer, manufactured by Asahi Kasei Kogyo Co., Ltd., trade name: Toughden 2000
* 2 Polymer B obtained in the above production example

<Preparation and evaluation of rubber composition>
According to the formulation shown in Table 2, a rubber composition for tires was prepared by kneading and compounding using a Banbury mixer. The obtained tire rubber composition was vulcanized at 145 ° C. for 45 minutes, and then subjected to various measurements shown below. The results are shown in Table 2.

(5) Abrasion resistance The amount of wear was measured at room temperature using a Ramborn type wear tester, the reciprocal of the amount of wear was calculated, and Comparative Example 1 was taken as 100, and displayed as an index. The larger the index value, the smaller the amount of wear and the better the wear resistance.

<Production and evaluation of tire>
Furthermore, a pneumatic tire (tread: single layer structure) having a size of 185 / 70R14 was produced using the rubber composition as a tread rubber, and wet grip performance and rolling resistance performance were evaluated by the following methods. The results are shown in Table 1.

(6) Wet performance test (tire)
Wear the above tires on the axle, measure the distance from when the brakes are applied while driving on a wet surface with a depth of 1 cm at a speed of 60 km / h until the vehicle stops completely. displayed. The larger the index value, the shorter the distance to stop and the better the wet grip property.
(7) Rolling resistance performance Based on SAE J2452, the rolling resistance of each prototype tire was measured, and the rolling resistance of the tire of Comparative Example 1 was set to 100, and the index was expressed by the following formula. It shows that rolling resistance is so small that index value is large.
Rolling resistance performance (index) = (Rolling resistance of tire of Comparative Example 1 / Rolling resistance of test tire) × 100

* 3 Carbon Black N220 (Tokai Carbon Co., Ltd. Seest 6)
* 4 Terpene resin, YS resin PX1000 (manufactured by Yashara Chemical, softening point 100 ° C)
* 5 Hydrogenated terpene resin, Clearon P105 (manufactured by Yashara Chemical, softening point 105 ° C)
* 6 N- (1,3-Dimethylbutyl) -N'-phenyl-p-phenylenediamine
* 7 N, N'-Dicyclohexyl-2-benzothiazolylsulfenamide

  From the results of Table 2, Examples using rubber compositions comprising a combination of an aromatic vinyl compound-conjugated diene compound copolymer having a cis-1,4 bond content of 80% or more in the conjugated diene compound portion and natural rubber. It can be seen that the tires 1 and 2 are more excellent in wear resistance, wet grip performance and rolling resistance performance than the tires of Comparative Examples 1 and 2.

Claims (13)

The following general formula (I):

(In the formula, M represents a lanthanoid element, scandium or yttrium, Cp ^R independently represents unsubstituted or substituted indenyl, and R ^{a to} R ^f each independently represents an alkyl having 1 to 3 carbon atoms. And L represents a neutral Lewis base, and w represents an integer of 0 to 3), and the following general formula (II):

(In the formula, M represents a lanthanoid element, scandium or yttrium, Cp ^R each independently represents an unsubstituted or substituted indenyl group, and X ′ represents a hydrogen atom, a halogen atom, an alkoxide group, a thiolate group, an amide group. , A silyl group or a hydrocarbon group having 1 to 20 carbon atoms, L represents a neutral Lewis base, w represents an integer of 0 to 3, and the following general formula (III ):

(In the formula, M represents a lanthanoid element, scandium or yttrium, Cp ^R ′ represents an unsubstituted or substituted cyclopentadienyl, indenyl or fluorenyl, and X represents a hydrogen atom, a halogen atom, an alkoxide group or a thiolate group. represents an amide group, a silyl group or a hydrocarbon group having a carbon number of 1 to 20, L is a neutral Lewis base, w is, an integer of 0 to 3, [B] ^- is a non-coordinating Obtained by addition polymerization of an aromatic vinyl compound and a conjugated diene compound in the presence of a polymerization catalyst composition containing at least one complex selected from the group consisting of a half metallocene cation complex represented by , Aromatic vinyl compound-conjugated diene compound copolymer having a cis-1,4 bond amount of 80% or more in the conjugated diene compound portion, natural rubber, polyisoprene rubber and poly Rubber composition characterized in that the at least one selected from the group consisting of Tajiengomu comprising as a rubber component.   The rubber composition according to claim 1, further comprising 0.5 parts by mass or more and less than 100 parts by mass of a hydrogenated resin with respect to 100 parts by mass of the rubber component.   The rubber composition according to claim 2, wherein a difference in SP value between the rubber component and the hydrogenated resin is 1.5 or less.   The rubber composition according to claim 2, wherein the hydrogenated resin is a resin obtained by hydrogenating a petroleum resin or a natural resin.   The rubber composition according to claim 4, wherein the hydrogenated resin is a hydrogenated terpene resin obtained by hydrogenating a terpene resin.   The rubber composition according to claim 5, wherein the hydrogenated terpene resin has a softening point of 80 to 180 ° C.   The rubber composition according to claim 1 or 2, wherein the total content of natural rubber, polyisoprene rubber and polybutadiene rubber in the rubber component is 50% by mass or more.   The rubber composition according to claim 1 or 2, wherein a vinyl bond amount of the conjugated diene compound portion is 10% or less.   The aromatic vinyl compound-conjugated diene compound copolymer is characterized in that the block amount in the NMR measurement of the repeating unit of the aromatic vinyl compound portion is 10% or less of the total aromatic vinyl compound portion. The rubber composition according to 1 or 2.   The rubber composition according to claim 1 or 2, wherein the aromatic vinyl compound-conjugated diene compound copolymer has a melting point (Tm) in DSC measurement.   The rubber composition according to claim 1, wherein the aromatic vinyl compound-conjugated diene compound copolymer is a styrene-butadiene copolymer.   A tire comprising the rubber composition according to any one of claims 1 to 11 for any tire member.   The tire according to claim 12, wherein the tire member is a tread.