TW201839042A - Crosslinked rubber and tire - Google Patents

Abstract

A crosslinked rubber obtained by crosslinking a rubber composition, wherein the rubber composition contains: (A) a conjugated diene polymer having a weight-average molecular weight of 1.0 * 105 to 2.0 * 106 in terms of polystyrene by gel permeation chromatography, the hydrogenation rate of structural units derived from butadiene being 60-90%; (B) a hydrogenated or un-hydrogenated conjugated diene polymer having structural units derived from butadiene and having a different hydrogenation rate than does component (A); (C) silica; and (D) a crosslinking agent, the co-vulcanization parameter represented by numerical formula (1) in the rubber composition being 0.85 or higher. (1): Co-vulcanization parameter = X/(Y * [alpha] + Z * [beta]).

Description

Cross-linked rubber and tires

The present application is based on Japanese Patent Application No. 2017-90717, filed on Apr.

This disclosure relates to a crosslinked rubber and tire.

The conjugated diene polymer obtained by polymerization using a conjugated diene compound is widely used for pneumatic tires because of various properties such as heat resistance, abrasion resistance, mechanical strength, and moldability. ) or anti-vibration rubber, hose and other industrial products.

For example, as a rubber composition for producing a tread or a side wall of a pneumatic tire, in order to improve the durability or wear resistance of the tire, it is known to contain a conjugated diene system together. A reinforcing agent such as a polymer, carbon black or cerium oxide. Among them, cerium oxide is effective in terms of both wet grip performance and low rolling resistance of tires, and is improved in durability and wear resistance, and has been actively used in recent years.

A hydrogenated conjugated diene polymer obtained by hydrogenating a butadiene portion using a conjugated diene polymer has been proposed as a polymer component of a rubber composition for a tire (see, for example, Patent Documents 1 to 5) ). Patent Document 1 discloses a rubber composition comprising a styrene-butadiene copolymer having a specific microstructure and a hydrogenated styrene-butadiene copolymer having a specific microstructure in a specific compounding ratio. Further, Patent Document 2 discloses a rubber composition containing a hydrogenated conjugated diene polymer, cerium oxide, an organic decane coupling agent, and a vulcanizing agent.

Patent Document 3 describes a rubber composition containing (A) a halogenated butyl rubber or a halide of a copolymer of isobutylene and p-methylstyrene, and (B) a styrene-butyl group having a specific microstructure. a diene copolymer, (C) a hydrogenated product of a low molecular weight styrene-butadiene copolymer having a specific microstructure, (D) cerium oxide, (E) a softening agent, and (F) a decane coupling agent. Patent Document 4 describes a rubber composition comprising a hydrogenated conjugated diene polymer modified with a compound having an ester group and/or a carboxyl group, and a hydrogenation modified by a compound having a nitrogen-containing heterocyclic group. A conjugated diene polymer and cerium oxide.

Further, Patent Document 5 discloses a hydride of a modified conjugated diene polymer having a functional group such as an amine group or an alkoxyalkyl group at a single terminal or both ends to obtain a high strength and low abrasion tire member. . In the examples of Patent Document 5, an example in which a modified hydrogenated conjugated diene polymer having a hydrogenation ratio of 60% or more is blended in a rubber composition is disclosed, and it is clear that compared with Comparative Example 1 in which hydrogenation is not performed. The strength and wear resistance of the vulcanized rubber are improved. [Prior Art Document] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2000-129037 [Patent Document 2] International Publication No. 1996/005250 [Patent Document 3] Japanese Patent Laid-Open Publication No. 2005-290139 [Patent Document 4] Japanese Patent Laid-Open Publication No. 2013 -144743 [Patent Document 5] International Publication No. 2014/133097

[Problems to be Solved by the Invention] A conjugated diene polymer having a high hydrogenation ratio is expensive, and it is considered to be a practical disadvantage in terms of cost in terms of production of a rubber product having excellent strength. Therefore, there is a need to develop a material which can suppress the cost of raw materials and obtain a rubber product excellent in strength.

The present disclosure has been made in view of the above problems, and an object thereof is to provide a crosslinked rubber which is produced at a high strength and at a low price. [Means for solving the problem]

According to the present disclosure, the following crosslinked rubber and tire are provided.

[1] A crosslinked rubber which is a crosslinked rubber obtained by crosslinking a rubber composition, and the rubber composition contains the following (A) to (D): (A) a hydrogenated conjugated diene polymer a polystyrene-equivalent weight average molecular weight of Gel Permeation Chromatography (GPC) of 1.0×10 ⁵ to 2.0×10 ⁶ , having a structural unit derived from butadiene, and when The structural unit represented by the following formula (2), the structural unit represented by the following formula (3), the structural unit represented by the following formula (4), and the structural unit represented by the following formula (5) When the ratio is set to p, q, r, and s, the following equation (6) is satisfied; 0.60 ≦ (p + r) / (p + q + r + s) ≦ 0.90 (6) [Chemical 1] (B) a hydrogenated or unhydrogenated conjugated diene polymer having a structural unit derived from butadiene and having a hydrogenation ratio different from that of the component (A); (C) cerium oxide; and (D) crosslinking The co-vulcanization parameter represented by the following formula (1) in the rubber composition is 0.85 or more. Co-vulcanization parameter=X/(Y×α+Z×β) (1) (In the formula (1), α is relative to the (A) component and the (B) in the rubber composition The content ratio of the component (A) in terms of the total amount of the components, and β is the total amount of the component (A) and the component (B) in the rubber composition. B) The content ratio of the component satisfies the relationship of α + β = 1. X is a condition in which the rubber composition is used as a sample at a cross-linking temperature and an amplitude angle of ±1° and a torsional vibration number of 100 cpm. The torque difference obtained by subtracting the minimum torque from the maximum torque within 30 minutes measured by a vibrating vulcanization tester is used, and Y is used to replace the component (B) in the rubber composition with The torque difference when the component (A) is used as a sample, and Z is a sample obtained by replacing the component (A) in the rubber composition with the component (B). The torque difference at the time) [2] A tire having at least a tread or a sidewall formed by the crosslinked rubber of [1]. [Effects of the Invention]

In the rubber composition containing at least a hydride as a conjugated diene polymer, a part of the conjugated diene polymer in the rubber composition is a polymer having a low hydrogenation rate. In this case, a high-strength crosslinked rubber excellent in tensile strength and elongation at break can also be obtained. Therefore, high-strength rubber products can be manufactured at a low price.

The crosslinked rubber of the present invention is a crosslinked rubber obtained by crosslinking a rubber composition, and the rubber composition contains the following (A) to (D): (A) a conjugated diene polymer by coagulation The polystyrene-equivalent weight average molecular weight of the gel permeation chromatography is 1.0×10 ⁵ to 2.0×10 ⁶ , and the hydrogenation rate of the structural unit derived from butadiene is 60% to 90%; (B) Conjugation II An olefin polymer (excluding the component (A)); (C) cerium oxide; and (D) a crosslinking agent, and the co-vulcanization parameter represented by the formula (1) is 0.85 or more . Hereinafter, each component contained in the rubber composition used for the production of the crosslinked rubber of the present invention will be described in detail.

<Component (A)> The conjugated diene polymer (hereinafter also referred to as "polymer (A)") of the component (A) is obtained by hydrogenating a polymer having a structural unit derived from a conjugated diene compound. Hydride. The polymer (A) can be produced by a method comprising the following polymerization step and hydrogenation step.

(Polymerization step) This step is a step of obtaining a conjugated diene polymer having an active terminal by polymerizing a monomer containing a conjugated diene compound. The conjugated diene compound used for the polymerization may be 1,3-butadiene alone or a conjugated diene compound other than 1,3-butadiene (hereinafter also referred to as "other conjugated diene compound"). ). Examples of the other conjugated diene compound include isoprene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, and 1,3-hexane. Alkene, 1,3-heptadiene, 2-phenyl-1,3-butadiene, 3-methyl-1,3-pentadiene, 2-chloro-1,3-butadiene, and the like. Among these, isoprene and 2,3-dimethyl-1,3-butadiene are preferred.

At the time of the polymerization, only the conjugated diene compound may be used, but from the viewpoint of improving the strength of the obtained crosslinked rubber, the polymer (A) is preferably a conjugated diene compound and an aromatic vinyl compound. Copolymer. Examples of the aromatic vinyl compound used in the polymerization include styrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, α-methylstyrene, and 2,4. -dimethylstyrene, 2,4-diisopropylstyrene, 4-tert-butylstyrene, 5-t-butyl-2-methylstyrene, vinylethylbenzene, divinyl Benzene, trivinylbenzene, divinylnaphthalene, tert-butoxystyrene, vinylbenzyldimethylamine, (4-vinylbenzyl)dimethylaminoethyl ether, N,N- Dimethylaminoethylstyrene, N,N-dimethylaminomethylstyrene, 2-ethylstyrene, 3-ethylstyrene, 4-ethylstyrene, 2-third Styrene, 3-tert-butylstyrene, 4-tert-butylstyrene, vinylxylene, vinylnaphthalene, vinylpyridine, diphenylethylene, diphenylethylene containing tertiary amine groups (e.g., 1-(4-N,N-dimethylaminophenyl)-1-phenylethene, etc.) and the like. Among these, an aromatic vinyl compound is preferably styrene or α-methylstyrene.

When the conjugated diene polymer in the present disclosure is a copolymer of a conjugated diene compound and an aromatic vinyl compound, it is preferably a single one in terms of high activity in anionic polymerization. A polymer comprising 1,3-butadiene and styrene is included in the bulk composition. The copolymer is preferably a random copolymerized portion having an irregular distribution of a conjugated diene compound and an aromatic vinyl compound. The copolymer may further have a block portion comprising a conjugated diene compound or an aromatic vinyl compound.

When the conjugated diene polymer is a copolymer of a conjugated diene compound and an aromatic vinyl compound, the balance between low hysteresis loss characteristics and wet skid resistance of the obtained crosslinked rubber is good. In the total amount of the conjugated diene compound and the aromatic vinyl compound used in the polymerization, the use ratio of the aromatic vinyl compound is preferably 3% by mass to 55% by mass, more preferably It is 5 mass% to 50 mass%. Further, the content ratio of the structural unit derived from the aromatic vinyl compound in the polymer is a value measured by ¹ H-nuclear magnetic resonance (NMR). The conjugated diene compound and the aromatic vinyl compound may be used alone or in combination of two or more.

At the time of the polymerization, a compound other than the conjugated diene compound and the aromatic vinyl compound (hereinafter also referred to as "other monomer") may be used as the monomer. Examples of the other monomer include acrylonitrile, methyl (meth)acrylate, and ethyl (meth)acrylate. The use ratio of the other monomer is preferably 10% by mass or less, and more preferably 5% by mass or less based on the total amount of the monomers used in the polymerization.

As the polymerization method to be used, any of a solution polymerization method, a gas phase polymerization method, and a bulk polymerization method can be used, but a solution polymerization method is particularly preferred. Further, as the polymerization form, any of a batch type and a continuous type can be used. In the case of using the solution polymerization method, an example of a specific polymerization method is exemplified in the presence of a polymerization initiator and a randomizer used as needed in an organic solvent. A method of polymerizing a monomer of a diene compound.

As the polymerization initiator, at least one of an alkali metal compound and an alkaline earth metal compound can be used. Specific examples of such examples include alkyl lithium such as methyl lithium, ethyl lithium, n-propyl lithium, n-butyl lithium, second butyl lithium, and third butyl lithium, and 1,4-arylene. Lithium dilithium (1,4-dilithiobutane), phenyl lithium, lithium stilbene, naphthyl lithium, 1,3-bis(1-litho-1,3-dimethylpentyl)benzene, 1,3 - phenyl bis(3-methyl-1-phenylpentylene) dilithium, sodium naphthalenyl, potassium naphthyl, di-n-butyl magnesium, di-n-hexyl magnesium, potassium ethoxide, stearic acid Calcium acid and the like. Among these, a lithium compound is preferred. The total amount of the polymerization initiator to be used is preferably from 0.2 mmol to 20 mmol based on 100 g of the monomer used in the polymerization.

The polymerization reaction can be carried out using a mixture of at least one of an alkali metal compound and an alkaline earth metal compound and a compound having a functional group that interacts with cerium oxide as a polymerization initiator. By carrying out the polymerization in the presence of the mixture, the polymerization starting end of the conjugated diene polymer can be modified by a functional group that interacts with cerium oxide. In the present specification, the "functional group that interacts with cerium oxide" means a group having an element that interacts with cerium oxide such as nitrogen, sulfur, phosphorus, or oxygen. The term "interaction" refers to the formation of covalent bonds between molecules or the formation of intermolecular forces weaker than covalent bonds (eg ion-dipole interactions, dipole-dipole interactions, hydrogen bonds, van der Waals forces) (Van der Waals force) is equal to the electromagnetic force acting between molecules).

Among them, a compound having a functional group that interacts with cerium oxide used in the modification of the polymerization initiation end is preferably a nitrogen-containing compound such as a secondary amine compound. Specific examples of the nitrogen-containing compound include dimethylamine, diethylamine, dipropylamine, dibutylamine, dodecamethyleneimine, and N,N'-dimethyl- N'-trimethyldecyl-1,6-diaminohexane, piperidine, pyrrolidine, hexamethyleneimine, heptamethyleneimine, dicyclohexylamine, N-methylbenzyl Amine, bis-(2-ethylhexyl)amine, diallylamine, morpholine, N-(trimethyldecyl)piperazine, N-(t-butyldimethylmethylalkyl)piperazine, 1,3-Di-trimethyldecyl-1,3,5-triazacyclohexane, and the like.

Further, at the time of the polymerization, at least one of an alkali metal compound and an alkaline earth metal compound, and a compound having a functional group that interacts with cerium oxide may be mixed in advance, and the mixture may be added to the polymerization. Aggregation is performed in the system. Alternatively, at least one of an alkali metal compound and an alkaline earth metal compound and a compound having a functional group that interacts with cerium oxide may be added to the polymerization system, and the two may be mixed in a polymerization system. polymerization.

The randomizer can be used for the purpose of adjusting the content of the vinyl bond indicating the content of the vinyl bond in the polymer. Examples of the randomizer include dimethoxybenzene, tetrahydrofuran, dimethoxyethane, diethylene glycol dibutyl ether, diethylene glycol dimethyl ether, and 2,2-di(tetrahydrofuranyl). ) Propane, 2-(2-ethoxyethoxy)-2-methylpropane, triethylamine, pyridine, N-methylmorpholine, tetramethylethylenediamine, and the like. These may be used alone or in combination of two or more.

The organic solvent to be used in the polymerization may be an organic solvent which is inert during the reaction, and for example, an aliphatic hydrocarbon, an alicyclic hydrocarbon or an aromatic hydrocarbon can be used. Among them, a hydrocarbon having 3 to 8 carbon atoms is preferable, and specific examples thereof include propane, n-butane, isobutane, n-pentane, isopentane, n-hexane, cyclohexane, and propylene. -butene, isobutylene, trans-2-butene, cis-2-butene, 1-pentyne, 2-pentyne, 1-hexene, 2-hexene, benzene, toluene, xylene, B Alkylbenzene, heptane, cyclopentane, methylcyclopentane, methylcyclohexane, 1-pentene, 2-pentene, cyclohexene, and the like. Further, as the organic solvent, one type may be used alone or two or more types may be used in combination.

In the case of the solution polymerization, the monomer concentration in the reaction solvent is preferably from 5% by mass to 50% by mass, more preferably 10% by mass, from the viewpoint of maintaining the balance between productivity and ease of polymerization control. ～30% by mass. The temperature of the polymerization reaction is preferably from -20 ° C to 150 ° C, more preferably from 0 ° C to 120 ° C. Further, the polymerization reaction is preferably carried out under a sufficient pressure to substantially maintain the monomer in a liquid phase. Such a pressure can be obtained by pressurizing the inside of the reactor by a gas inert to the polymerization reaction or the like.

By such a polymerization reaction, a conjugated diene polymer having an active terminal can be obtained. With respect to the obtained conjugated diene polymer, the content of the vinyl bond in the butadiene unit is preferably 20% by mass to 70% by mass, more preferably 23% by mass to 68% by mass, and still more preferably 25% by mass. ~65 mass%. When the content of the vinyl bond is less than 20% by mass, the gripping property tends to be low, and when the content of the vinyl bond exceeds 70% by mass, the abrasion resistance of the obtained vulcanized rubber tends to decrease. In the present specification, the "vinyl bond content" is a content ratio of a structural unit having a 1,2-bond with respect to all structural units of butadiene in the conjugated diene polymer. The value is a value measured by ¹ H-NMR.

(Hydrogenation step) In this step, the conjugated diene polymer obtained by the polymerization step is hydrogenated. The method and conditions for hydrogenation are not particularly limited as long as a polymer having a desired hydrogenation ratio can be obtained. As an example of the hydrogenation method, there is a method in which a catalyst containing an organometallic compound of titanium as a main component is used as a hydrogenation catalyst; and a catalyst containing an organic compound of iron, nickel or cobalt and an organometallic compound such as an aluminum alkyl is used. Method; a method of using an organic complex of an organometallic compound such as ruthenium or osmium; or a method of supporting a catalyst such as palladium, platinum, rhodium, cobalt or nickel on a carrier such as carbon, cerium oxide or alumina . In various methods, an organometallic compound of titanium alone or a homogeneous catalyst of an organometallic compound containing titanium and an organometallic compound of lithium, magnesium, or aluminum is used (Japanese Patent Publication No. Sho 63-4841, Japanese Patent Special Fair 1) -37970) The method of hydrogenating under mild conditions of low pressure and low temperature is industrially preferable, and the hydrogenation selectivity of the double bond derived from butadiene is also high, which is suitable for the purpose of the present disclosure.

Hydrogenation can be carried out in a solvent which is inert to the catalyst and which can dissolve the conjugated diene polymer. Preferred solvents are aliphatic hydrocarbons such as n-pentane, n-hexane and n-octane, alicyclic hydrocarbons such as cyclohexane and cycloheptane, and aromatic hydrocarbons such as benzene and toluene. A single type of ether such as diethyl ether or tetrahydrofuran, or a mixture of these main components.

The hydrogenation reaction is generally carried out by maintaining the polymer at a predetermined temperature under hydrogen or an inert atmosphere, adding a hydrogenation catalyst with or without stirring, and then introducing hydrogen gas to be pressurized to a predetermined pressure. By inert environment is meant an environment that does not react with any of the participants of the hydrogenation reaction, such as by hydrazine, hydrazine, argon, and the like. The hydrogenation reaction process for obtaining a hydrogenated conjugated diene polymer can be carried out using any of a batch process, a continuous process, and a combination of these. The amount of the hydrogenation catalyst added is preferably from 0.02 mmol to 20 mmol per 100 g of the conjugated diene polymer before hydrogenation.

In the polymer (A), the hydrogenation rate of the butadiene-derived structural unit of the polymer (A) is in the range of 60% to 90%. When the hydrogenation ratio of the polymer (A) is 60% or more, a crosslinked rubber having sufficiently high mechanical strength (tensile strength) and elongation at break can be obtained. In terms of sufficiently improving the tensile strength of the obtained crosslinked rubber, the lower limit of the hydrogenation ratio is preferably 63% or more, more preferably 65% or more, and still more preferably 68% or more. In addition, the upper limit of the hydrogenation rate is 90% or less, preferably 85% or less, from the viewpoint of suppressing the decrease in the production efficiency and sufficiently securing the tensile strength of the crosslinked rubber and achieving a low price. Further, it is preferably set to 80% or less. Further, the hydrogenation ratio is a value measured by ¹ H-NMR. The hydrogenation rate can be arbitrarily selected by changing the amount of the hydrogenation catalyst, the hydrogen pressure at the time of the hydrogenation reaction, and the reaction time.

The hydrogenated conjugated diene polymer of the present disclosure can be obtained by removing a solvent from the solution obtained and separating the polymer. In order to separate the polymer, for example, it can be carried out by a known desolvation method such as steam stripping or a drying operation such as heat treatment.

The polymer (A) may be an unmodified conjugated diene polymer, but in terms of improving the dispersibility of cerium oxide and improving low hysteresis loss characteristics, it is preferably selected from an amine group. One or more functional groups (hereinafter also referred to as "specific functional groups") in a group consisting of a group containing a carbon-nitrogen double bond, a nitrogen-containing heterocyclic group, a phosphino group, a thiol group, and a hydrocarbyloxyalkyl group Modified polymer. The method of the modification is not particularly limited, and examples thereof include: [1] a method of using a mixture of at least one of an alkali metal compound and an alkaline earth metal compound and a compound having a specific functional group as a polymerization initiator; A method of reacting a conjugated diene polymer having an active terminal obtained by the polymerization step, a compound having a specific functional group, or the like. Among them, it is preferred to use the method [2] alone or in combination with the method [1] and the method [2]. In this case, the polymer (A) preferably hydrogenates the reaction product of the active terminal of the conjugated diene polymer and the compound having a specific functional group and reacting with the active terminal of the conjugated diene polymer. A hydrogenated conjugated diene polymer.

(End Modification Step) In the method [2], a compound which reacts with a polymer having an active terminal, as long as it has a specific functional group and can react with the active terminal of the conjugated diene polymer The compound (hereinafter also referred to as "compound (C)") is not particularly limited. Preferable specific examples of the compound (C) include the following (I) to (III).

(I) the compound (C-1) represented by the following formula (2); [Chemical Formula 1] (In the formula (2), A ¹ is at least one atom selected from the group consisting of a nitrogen atom, a phosphorus atom and a sulfur atom, does not have an active hydrogen, and utilizes a nitrogen atom, a phosphorus atom or a sulfur atom with R ⁵ is a monovalent functional group to be bonded. R ³ and R ⁴ are a hydrocarbon group, R ⁵ is a hydrocarbon group, and n is an integer of 0 to 2. In the case where a plurality of R ³ and R ⁴ are present, a plurality of R ³ and R ⁴ may be the same or different)

(II) a compound (C-2) having one or more functional groups G ¹ and a group G ² in the molecule, the functional group G ¹ being selected from the group consisting of a cyclic ether group, a (thio)carbonyl group and a different ( groups of at least one thio) cyanate group consisting of the group G ² having a nitrogen atom selected from the group consisting of, at least one atom (wherein a nitrogen group consisting of a phosphorus atom, an oxygen atom and a sulfur atom At least any one of an atom, a phosphorus atom and a sulfur atom may also be protected by a 3-substituted hydrocarbyl decyl group, and has no active hydrogen and is different from the functional group G ¹ ; (III) has two in the molecule The above iso(thio)cyanate group-containing compound (C-3);

Further, in the present specification, the (thio)carbonyl group means a carbonyl group and a thiocarbonyl group, and the iso(thio)cyanate group means an isocyanate group and an isothiocyanate group. As the compound (C), one type of the above may be used alone or two or more types may be used in combination.

In the above formula (2), the hydrocarbon group of R ³ and R ⁴ is preferably a linear or branched alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms or a carbon number of 6 to 20 carbon atoms. Aryl. R ^{5 is} preferably a linear or branched alkanediyl group having 1 to 20 carbon atoms, a cycloalkylene group having 3 to 20 carbon atoms or an extended aryl group having 6 to 20 carbon atoms. From the viewpoint of improving the reactivity with the conjugated diene polymer, n is preferably 0 or 1. A ¹ has at least one atom selected from the group consisting of a nitrogen atom, a phosphorus atom and a sulfur atom, and is bonded to R ⁵ using a nitrogen atom, a phosphorus atom or a sulfur atom. The nitrogen atom, the phosphorus atom and the sulfur atom in A ¹ are not bonded to the active hydrogen, and may also be protected by a protecting group.

In the present specification, the term "active hydrogen" means a hydrogen atom bonded to an atom other than a carbon atom, and preferably means a carbon-hydrogen bond having a bonding energy lower than that of a polymethylene group. The "protecting group" is a functional group which converts A ¹ into a functional group which is inert with respect to the polymerization active terminal, and examples thereof include a 3-substituted hydrocarbon decyl group.

Among them, A ^{1 is} preferably a group which becomes a cerium ion by a cerium salt generating agent. When the compound (C) has such a group (A ¹ ), the obtained hydrogenated conjugated diene polymer has excellent shape retention. Specific examples of A ¹ include, for example, a nitrogen-containing group in which two hydrogen atoms of a primary amino group are substituted by two protecting groups, and a hydrogen atom of a secondary amino group is substituted with a protecting group. a phosphorus group, a secondary phosphine, wherein a nitrogen group, a tertiary amino group, a group having a carbon-nitrogen double bond, a nitrogen-containing heterocyclic group, and a hydrogen atom of a primary phosphino group are substituted by two protecting groups. A sulfur-containing group in which a hydrogen atom of a group is substituted with a protecting group, a phosphorus group, a tertiary phosphino group, and a hydrogen atom of a thiol group, which are substituted with a protecting group. Among these, from the viewpoint of good affinity with cerium oxide, a group having a nitrogen atom is preferred. The protective group is not particularly limited, and examples thereof include a 3-substituted hydrocarbon alkylene group and the like.

As a specific example of the compound (C-1), a hydrogen atom having a hydrogen atom of a primary amino group substituted by two protecting groups and a hydrogen atom of a secondary amine group substituted by a protecting group Examples of the nitrogen-containing group or the tertiary amino group and the alkoxyalkylalkyl group include N,N-bis(trimethyldecyl)aminopropyltrimethoxydecane, and N,N-bis(III). Methyl decyl)aminopropylmethyldiethoxy decane, N,N',N'-tris(trimethyldecyl)-N-(2-aminoethyl)-3-aminopropyl Triethoxy decane, 3-(4-trimethyldecyl-1-piperazinyl)propylmethyldimethoxydecane, and the alkyl and alkanediyl groups in the compounds are respectively substituted A compound having an alkyl group having 1 to 6 carbon atoms or an alkyl 2 group having 1 to 6 carbon atoms.

As a compound having a group containing a carbon-nitrogen double bond or a nitrogen-containing heterocyclic group and an alkoxyalkyl group, for example, N-(1,3-dimethylbutylene)-3-(triethyl) Oxidylalkyl)-1-propanamine, N-(1-methylpropylene)-3-(triethoxydecyl)-1-propanamine, N-(4-N,N-dimethyl Aminobenzylidene)-3-(triethoxydecyl)-1-propanamine, N-(cyclohexylene)-3-(triethoxydecyl)-1-propanamine, N- (3-trimethoxydecylpropyl)-4,5-dihydroimidazole, N-(3-trimethoxydecylpropyl)imidazole, 3-hexamethyleneiminopropyltrimethoxydecane , 3-hexamethyleneiminopropylmethyldimethoxydecane, 3-(1-piperidinyl)propyltrimethoxydecane, 3-(1-hexamethyleneimido)propane Tris-methoxydecane, 3-(1-piperazinyl)propyltrimethoxydecane, 3-morpholinylpropyltrimethoxydecane, and the alkyl and alkanediyl groups in the compounds are respectively substituted A compound having an alkyl group having 1 to 6 carbon atoms or an alkyl 2 group having 1 to 6 carbon atoms.

a phosphorus-containing group having a phosphorus atom group substituted with two protecting groups, a phosphorus-containing group substituted with two protecting groups, a hydrogen atom of a second phosphino group substituted by a protecting group, a tertiary phosphorus group, Or a compound containing a sulfur group and alkoxyalkylene group in which one hydrogen atom of a thiol group is substituted by a protecting group, for example, P,P-bis(trimethyldecyl)phosphinylpropyl group Methyldimethoxydecane, P,P-bis(trimethyldecyl)phosphinopropyltrimethoxydecane, 3-dimethylphosphinopropyltrimethoxydecane, 3-dimethylphosphino Propylmethyldimethoxydecane, 3-diphenylphosphinopropyltrimethoxydecane, 3-diphenylphosphinopropylmethyldimethoxydecane, S-trimethyldecylalkylthiopropane a methyl dimethoxy decane, an S-trimethyl decyl decyl propyl trimethoxy decane, and an alkyl group or an alkyl di group in the above compounds, respectively substituted with an alkyl group having 1 to 6 carbon atoms, carbon A compound obtained by using an alkanediyl group of 1 to 6 or the like. Examples of the compound having an iso(thio)cyanate group include 3-isocyanatopropyltrimethoxydecane, 3-isocyanatopropyltriethoxydecane, and the like.

The compound (C-2) is preferably such that the group G ² is a group containing a nitrogen atom which is not bonded to an active hydrogen. Specific examples of the compound (C-2) in this case include an epoxy group compound such as tetraglycidyl-1,3-diaminomethylcyclohexane, and the like; Examples of the compound having a (thio)carbonyl group include 4-aminoacetophenone such as 4-N,N-dimethylaminobenzophenone; 1,7-bis(methylethylamino)-4. - bis(dihydrocarbylaminoalkyl) ketone such as heptanone; dialkylaminoalkyl (meth) acrylate such as 2-dimethylaminoethyl acrylate; 1,3-dimethyl-2- Hydrocarbyl imidazolidinone such as imidazolidinone; N-hydrocarbyl pyrrolidone such as 1-phenyl-2-pyrrolidone; N-hydrocarbyl caprolactam such as N-methyl-ε-caprolactam; N, N N-dihydrocarbylcarbendazim such as diethylformamide; N,N-dihydrocarbylacetamide such as N,N-dimethylacetamide; N,N-dimethylpropenamide, etc. Examples of the compound having an iso(thio)cyanate group include 3-isocyanatopropyltrimethoxydecane.

Examples of the compound (C-3) include 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, diphenylmethane diisocyanate, naphthalene diisocyanate, triphenylmethane triisocyanate, and p-phenylene diisocyanate. , tris(isocyanatophenyl)phosphorothioate, xylene diisocyanate, benzene-1,2,4-triisocyanate, naphthalene-1,2,5,7-tetraisocyanate, 1,4-benzene Diisoisothioisocyanate and the like.

As the compound (C), the compound (C-1) is particularly preferably used in terms of affinity with cerium oxide. Further, in the case of using the compound (C-1), for the purpose of adjusting the Mona viscosity of the modified conjugated diene polymer, it is also possible to use ruthenium tetrachloride in combination with the compound (C-1). A coupling agent such as an epoxy group-containing compound (for example, tetraglycidyl-1,3-diaminomethylcyclohexane or the like). As the compound (C), one type of these may be used alone or two or more types may be used in combination.

The reaction of the polymer having an active terminal with the compound (C) can be carried out, for example, in the form of a solution reaction. The solution reaction can be carried out by using a solution containing an unreacted monomer after the completion of the polymerization reaction, or the conjugated diene polymer contained in the solution can be separated and dissolved in a suitable solvent such as cyclohexane. . Further, the reaction can also be carried out using any of a batch type and a continuous type. In this case, the method of adding the compound (C) is not particularly limited, and examples thereof include a method of adding one time, a method of separately adding, a method of continuously adding, and the like. The terminal modification reaction is preferably carried out before the hydrogenation step.

In the reaction, the proportion of the compound (C) to be used may be appropriately set according to the kind of the compound (C), but it is preferably 0.1 mol with respect to the metal atom participating in the polymerization reaction of the polymerization initiator. The equivalent weight or more is more preferably 0.3 mole equivalent or more. By setting the amount to 0.1 mol equivalent or more, the reaction can be sufficiently carried out, and the dispersibility of cerium oxide can be preferably improved. Further, in terms of reducing the amount of unreacted materials in the solution after the reforming reaction, it is preferred to set the ratio of the use of the compound (C) to the metal atom participating in the polymerization reaction of the polymerization initiator. It is 1.2 molar equivalents, more preferably less than 1.0 molar equivalent. The temperature of the reaction is usually the same as the temperature of the polymerization reaction, and is preferably -20 ° C to 150 ° C, more preferably 0 ° C to 120 ° C, and particularly preferably 20 ° C to 100 ° C. When the reaction temperature is low, the viscosity of the modified conjugated diene polymer tends to increase. On the other hand, when the reaction temperature is high, the polymerization active terminal is easily deactivated. The reaction time is preferably from 1 minute to 5 hours, more preferably from 2 minutes to 1 hour.

In order to obtain the polymer (A) having a desired molecular weight, a coupling agent may also be reacted with the polymer having an active terminal obtained in the polymerization step. The coupling agent is not particularly limited, and examples thereof include succinimide, phthalimide, benzhydrylpyridine, dibutylphosphonium chloride, methyltrichloride, and methyldichloride. Antimony, Tetrachlorosilicon, antimony tetrabromide, antimony tetraiodide, trichloromethoxydecane, tribromomethoxydecane, trimethoxydecane, methyltriethoxydecane, tetramethyl Oxydecane, tetraethoxydecane, dimethyl adipate, dimethyl terephthalate, tin tetrachloride, tetrabromo tin, butyltin trichloride, methyltin trichloride , ethyl tin trichloride, phenyl tin trichloride, octyl tin trichloride, butyl tin trioctylate, dibutyl tin bislaurate, ethylene glycol diglycidyl ether, phosphorus trichloride, pyromellitic anhydride , divinylbenzene, trichloropropane, etc. Further, the coupling agent may be used alone or in combination of two or more.

The polymerization active end and the reaction with the coupling agent can be carried out, for example, in the form of a solution reaction. In the case of the reaction, the amount of the coupling agent to be used is preferably 0.1 mol equivalent or more, more preferably 0.3, based on the metal atom participating in the polymerization reaction of the polymerization initiator. More than the molar equivalent. Further, in terms of suppressing the molecular weight from becoming excessively large, the use ratio of the coupling agent is preferably set to less than 1.2 mol equivalents, more preferably set to the metal atom participating in the polymerization reaction of the polymerization initiator. It is less than 1.0 molar equivalent.

Gel permeation chromatography (GPC) of polymer (A) in terms of tensile strength, low fuel efficiency performance, and attrition resistance of the obtained crosslinked rubber, and processability of the rubber composition The polystyrene-equivalent weight average molecular weight (Mw) is 1.0 × 10 ⁵ to 2.0 × 10 ⁶ . When the Mw is less than 1.0 × 10 ⁵ , the obtained crosslinked rubber has poor tensile strength, low fuel efficiency performance, and abrasion resistance. When Mw is more than 2.0 × 10 ⁶ , the workability of the rubber composition is poor. More preferably, it is 1.3 × 10 ⁵ - 1.5 × 10 ⁶ , and further preferably 1.5 × 10 ⁵ - 1.0 × 10 ⁶ . The method of obtaining the polymer (A) having a weight average molecular weight within a range of the above-mentioned range, for example, a method of appropriately changing the amount of the polymerization initiator relative to the amount of the monomer used, or a method using a coupling agent, But it is not limited to these.

The polymer (A) obtained in the above manner is a hydrogenated conjugated diene polymer having a structural unit derived from a conjugated diene compound, when the structural unit represented by the formula (2), the formula (3) When the structural ratios of the structural unit, the structural unit represented by the formula (4), and the structural unit represented by the formula (5) are p, q, r, and s, respectively, The formula (6) is described. 0.60≦(p+r)/(p+q+r+s)≦0.90 (6) Further, the formula (6) indicates that the hydrogenation rate of the structural unit derived from butadiene is 60% or more. And less than 90%".

<Component (B)> The conjugated diene polymer (hereinafter also referred to as "polymer (B)") as the component (B) has a structural unit derived from butadiene and has a hydrogenation ratio and (A) A hydrogenated or unhydrogenated polymer having a different composition. Specifically, the polymer (B) is preferably a conjugated diene polymer (hereinafter also referred to as "polymer (b-1)") which is not hydrogenated, that is, a hydrogenation rate of 0%, and is derived from The hydrogenation rate of the structural unit of the diene is lower than at least one of the hydrogenated conjugated diene polymer (hereinafter also referred to as "polymer (b-2)") of the polymer (A). In this case, the polymer (B) is preferably hydrogenated or not satisfying the following formula (7) when (p+r)/(p+q+r+s) of the polymer (A) is θ. A hydrogenated conjugated diene polymer. 0≦(p+r)/(p+q+r+s)<θ (7) As the polymer (B), it is preferably polymerized in terms of being able to manufacture a high-strength article at a lower cost. (b-1). The polymer (B) is particularly preferably a copolymer of a conjugated diene compound and an aromatic vinyl compound.

The polymer (b-1) can be produced by a method comprising the same polymerization step as the polymer (A). Further, the polymer (b-2) can be produced by a method comprising the same polymerization step and hydrogenation step as the polymer (A). The polymer (B) may be either modified or non-modified, but in terms of further improving the dispersibility of the cerium oxide, it is preferred to have a single terminal or both ends of the polymer selected from the group consisting of One or more functional groups (specific functional groups) of the group consisting of an amine group, a group containing a carbon-nitrogen double bond, a nitrogen-containing heterocyclic group, a phosphino group, a thiol group, and a hydrocarbyloxyalkyl group. The polymerization of the polymer (A) can be applied to the details of the reaction conditions in the polymerization step and the terminal upgrading step to obtain the polymer (B), the kind and amount of the compound to be used, preferred examples, and the like. Description of the steps and end modification steps.

With regard to the hydrogenation step for obtaining the polymer (b-2), in terms of the crosslinking with the polymer (A) being sufficiently carried out to obtain a high-strength crosslinked rubber, and the production being made at a lower cost, The hydrogenation rate of the polymer (b-2) is preferably more than 0% and less than 55%, more preferably from 1% to 50%, still more preferably from 1% to 20%. Regarding the details of the method and conditions for hydrogenation, the description of the hydrogenation step of the polymer (A) can be applied. The difference in hydrogenation rate between the polymer (A) and the polymer (B) is preferably 20% or more, more preferably 50% or more, and still more preferably 70% or more.

The polymer (B) preferably has a weight average molecular weight in terms of polystyrene by GPC of 1.0 × 10 ⁵ to 2.0 × 10 ⁶ . When it is 1.0×10 ⁵ or more, the tensile strength of the obtained crosslinked rubber can be sufficiently improved, and when it is 2.0×10 ⁶ or less, it is preferable in terms of good workability. The lower limit of the weight average molecular weight of the polymer (B) is preferably 1.0 × 10 ⁵ or more, more preferably 1.5 × 10 ⁵ or more. Further, the upper limit is preferably 1.5 × 10 ⁶ or less, more preferably 1.0 × 10 ⁶ or less. Further, the polymer (B) may be used alone or in combination of two or more.

The content ratio of the polymer (A) and the polymer (B) in the rubber composition of the present invention is preferably such that the polymer (A) is contained in an amount of 100 parts by mass based on the polymer (B). The ratio is an amount of 5 parts by mass to 500 parts by mass. When the content ratio is less than 5 parts by mass, the tensile strength of the obtained crosslinked rubber tends to be low, and if it is more than 500 parts by mass, the product may not be sufficiently reduced in cost. The content ratio of the polymer (A) is preferably from 10 parts by mass to 450 parts by mass, more preferably from 15 parts by mass to 400 parts by mass, per 100 parts by mass of the polymer (B). When the co-vulcanization parameter has a ratio within the above range, the co-vulcanization parameter is not particularly limited, and the high tensile strength and the low cost can be uniformly exhibited. In terms of the ratio, when the total amount of the polymer (A) and the polymer (B) is 1, it is preferred to set the polymer (A): the polymer (B) (that is, α: β). 0.1 to 0.9: 0.9 to 0.1. α: β is more preferably 0.2 to 0.8: 0.8 to 0.2, and further preferably 0.4 to 0.6: 0.6 to 0.4. The total amount of the polymer (A) and the polymer (B) in the rubber composition is preferably 20% by mass to 70% by mass, and more preferably 30% by mass to 65% by mass based on the total amount of the rubber composition. quality%.

<Component (C)> As the cerium oxide to be blended in the rubber composition, for example, wet cerium oxide (aqueous ceric acid), dry cerium oxide (ceric anhydride), colloidal cerium oxide, precipitation Ceria, calcium citrate, aluminum citrate, etc. Among these, wet cerium oxide is particularly preferable from the viewpoint of the effect of improving the fracture resistance characteristics or the effect of both the wet grip and the low rolling resistance. Further, from the viewpoint of improving the dispersibility in the polymer composition and improving physical properties and workability, it is also preferred to use a high dispersible type of cerium oxide. The cerium oxide may be used alone or in combination of two or more.

The amount of cerium oxide in the rubber composition is preferably from 1 part by mass to 100 parts by mass per 100 parts by mass of the total amount of the polymer component, and if it is less than 1 part by mass, it is difficult to obtain cerium oxide. When the effect of improving the damage resistance is more than 100 parts by mass, the workability and the elongation at break tend to be lowered. The proportion of the cerium oxide is more preferably from 5 parts by mass to 95 parts by mass, even more preferably from 10 parts by mass to 90 parts by mass.

<Component (D)> A crosslinking agent is prepared in the rubber composition. Examples of the crosslinking agent include sulfur, sulfur halide, organic peroxide, anthraquinone, an organic polyamine compound, and an alkylphenol resin having a methylol group. Sulfur is usually used. In terms of obtaining a crosslinked rubber having various properties such as elasticity and tensile strength, the blending ratio of sulfur is preferably 0.1 part by mass based on 100 parts by mass of the total of the polymer components contained in the rubber composition. 5 parts by mass, more preferably 0.3 parts by mass to 3 parts by mass.

<Other Components> The rubber composition of the present invention may contain other components than the polymer (A), the polymer (B), the cerium oxide, and the crosslinking agent. For example, in the rubber composition, in addition to the polymer (A) and the polymer (B) obtained, other rubber components may be blended. The type of the rubber component is not particularly limited, and examples thereof include natural rubber (NR), isoprene rubber (IR), and styrene isoprene copolymer rubber. The blending ratio of the other rubber component is preferably 30 parts by mass or less, and more preferably 10 parts by mass or less, based on 100 parts by mass of the total of the polymer components contained in the rubber composition.

A reinforcing filler other than cerium oxide may be formulated in the rubber composition. Examples of such a reinforcing filler include carbon black, clay, and calcium carbonate. The reinforcing filler formulated in the rubber composition of the present disclosure is preferably cerium oxide alone or in combination with carbon black and cerium oxide. In the case where the carbon black is used in combination, the blending ratio of the carbon black to the total amount of the cerium oxide and the carbon black in the rubber composition is preferably 20% by mass or less, more preferably 10% by mass. the following.

Further, in the rubber composition, in order to oil-fill the elastomer, a generally used process oil may be blended as an oil for oil-filling. The process oil can be formulated into the rubber composition, for example, by directly adding the oil to the rubber formulation. Examples of preferred process oils include various oils known in the art, and examples thereof include aromatic oils, paraffin oils, naphthenic oils, vegetable oils, and oils having a low content of polycyclic aromatic compounds (lowly a polycyclic aromatics (PCA) oil, for example, a mild extraction solvent (MES: mild extraction solvate), an oil obtained by treating an aromatic extract from distilled oil (TDAE: treated distillate aromatic extract), An aromatic special extract (SRAE: residual residual aromatic extract) and a heavy naphthenic oil derived from the remaining oil. Examples of commercially available MES, TDAE, and SRAE include Catenex SNR (heavy paraffin wax obtained by dewaxing a distillation oil by a solvent) manufactured by Shell of MES, as TDAE. Vivatec 500 manufactured by H&R Wasag AG and NC140 manufactured by Japan Energy Corp. of SRAE. The blending amount of the process oil is preferably from 10 parts by mass to 100 parts by mass based on 100 parts by mass of the total of the polymer components contained in the rubber composition.

In the rubber composition, in addition to the components, for example, an anti-aging agent, a zinc oxide, a stearic acid, a softener, a vulcanization accelerator, a decane coupling agent, a compatibilizer, a vulcanization aid, a processing aid, or the like may be formulated. Filler oils and scorch inhibitors are equivalent to the various additives generally used in rubber compositions. These blending ratios can be appropriately selected depending on various components within a range that does not impair the effects of the present disclosure.

The co-vulcanization parameter represented by the above formula (1) for obtaining the rubber composition of the crosslinked rubber of the present invention is 0.85 or more. By using a rubber composition having a co-vulcanization parameter of 0.85 or more, a high-strength crosslinked rubber which exhibits good tensile strength and good elongation at break in a balanced manner can be obtained. Further, in the rubber composition in which two polymers are blended, it can be said that the larger the value of the co-vulcanization parameter, the more excellent the co-vulcanizability of the two polymers. When the co-vulcanization parameter is less than 0.85, the obtained crosslinked rubber is inferior in tensile strength or insufficient elongation at break. The co-vulcanization parameter is preferably 0.86 or more. In addition, the upper limit of the co-vulcanization parameter is not particularly limited, and is preferably 1.20 or less, and more preferably 1.10 or less, from the viewpoint of suppressing the decrease in the elongation at break or achieving a sufficient cost reduction. Furthermore, in the present specification, the X and Y (torque difference) of the co-vulcanization parameter are based on Japanese Industrial Standards (JIS)-K6300-2, and the vibrating vulcanization tester is used to make the rubber composition The obtained temperature was measured under the conditions of an amplitude angle of ±1° and a torsional vibration number of 100 cpm.

The method for obtaining the rubber composition having the co-vulcanization property is not particularly limited, and for example, the blending ratio of the polymer (A) to the polymer (B) (α, β) is appropriately changed in the preparation of the rubber composition. And a temperature condition at the time of crosslinking of the rubber composition, a method of changing the hydrogenation rate of the polymer (A) and the polymer (B), or a method of combining two or more of these. Further, it is presumed that the crosslinking between the polymer (A) and the polymer (B) is sufficiently performed by the co-vulcanization parameter of 0.85 or more, and the weight average molecular weight of the polymer (A) is sufficiently high to be 1.0. × 10 ⁵ ~ 2.0 × 10 ⁶ and a sufficiently high hydrogenation rate of 60% or more, the use of the rubber composition and a crosslinked rubber obtained by equalization may exhibit good tensile strength and good elongation at break.

<Crosslinked Rubber and Tire> The crosslinked rubber of the present disclosure can be produced by kneading and crosslinking the rubber composition. That is, in addition to the polymer (A), the polymer (B), the ceria, and the crosslinking agent, the rubber composition also uses an open kneader (for example, a roll) or a closed kneader (for example, Bamburi kneading). A mixing machine such as a banbury mixer is used to knead the components to be blended as needed, and after cross-linking (vulcanization) at a temperature of, for example, 120 ° C to 180 ° C after the forming process, it can be applied as a crosslinked rubber. Various rubber products. Specifically, the crosslinked rubber of the present disclosure can be applied, for example, to a tire tread, an under tread, a carcass, a sidewall, a bead part, and the like; Sealing materials such as gaskets, gaskets, weather strips, O-rings, etc.; interior and exterior packaging materials for automobiles, ships, airplanes, railways, etc.; construction materials; anti-vibration for industrial machinery or equipment Rubber; diaphragm, roller, radiator hose, air hose, etc. hoses and hose covers; power transmission belts, etc.; lining ; dust boot; medical machine material; fender; wire insulation; other industrial products. In particular, the crosslinked rubber obtained by using the rubber composition is excellent in wet skid resistance, low hysteresis loss characteristics, tensile strength, and abrasion resistance, and can be preferably used as a tread and a side wall of a tire. material.

The manufacture of the tire can be carried out according to a conventional method. For example, a rubber composition is mixed by a kneading machine, and each formed into a sheet shape is placed at a predetermined position by a conventional method and vulcanized and formed, thereby forming a tread rubber or a side rubber, thereby obtaining a pneumatic tire. [Examples]

Hereinafter, the present invention will be specifically described based on examples, but the present invention is not limited to the examples. In addition, "part" and "%" in an Example and a comparative example are a mass basis unless it demonstrates especially. Moreover, the measuring method of various physical property values is shown below.

[Bonding styrene content (%)]: It was determined by ¹ H-NMR measurement at 500 MHz. [weight-average molecular weight after reforming]: apex of the maximum peak of the GPC curve obtained by using gel permeation chromatography (HLC-8120GPC (trade name (manufactured by Tosoh))) The equivalent holding time is obtained by conversion of polystyrene. (GPC conditions) Column: The product name "GMHXL" (manufactured by Tosoh) Two columns Temperature: 40 ° C Mobile phase: Tetrahydrofuran flow rate: 1.0 ml / min Sample concentration: 10 mg / 20 ml [Hydrogenation Rate (%)]: The hydrogenation rate of the butadiene unit was determined by ¹ H-NMR at 500 MHz.

<Synthesis of Polymer> [Synthesis Example 1] In an autoclave reactor having an internal volume of 50 liters substituted with nitrogen, 25800 g of cyclohexane, 201 g of tetrahydrofuran, 1,462 g of styrene, and 1,3-butyl were charged. Alkene 2193 g. After the temperature of the reactor contents was adjusted to 40 ° C, a cyclohexane solution containing 2.84 g of n-butyllithium was added to initiate polymerization. The polymerization is carried out under heat insulation conditions. When the temperature of the reactor contents reached 65 ° C, 645 g of butadiene was added in 15 minutes, and after further polymerization for 3 minutes, 0.58 g of ruthenium tetrachloride was added. After 5 minutes, 6.8 g of [N,N-bis(trimethyldecyl)aminopropyl]methyldiethoxydecane was added and reacted for 15 minutes. The reaction solution was set to 80 ° C or higher, and hydrogen was introduced into the system, after which, [bis(η5-cyclopentadienyl)titanium (fluorenyloxy) chloride] 2.76 g, diethyl chloride was added. 2.83 g of aluminum and 1.18 g of n-butyllithium were reacted so that the hydrogen pressure was 0.7 MPa or more until the hydrogenation rate became 50%. After reaching the flow rate of the predetermined amount of hydrogen, the reaction solution was returned to normal temperature and normal pressure, and extracted from the reaction vessel to obtain a polymer solution. The weight average molecular weight of the polymer was measured by GPC and found to be 200,000. Then, the solvent was removed by steam stripping (steam temperature: 190 ° C) for 2 hours at a temperature of the liquid phase of the desolventizing tank at 95 ° C, and dried by a hot roll adjusted to 110 ° C. Thus, a conjugated diene polymer P having a hydrogenation ratio of 50% was obtained. The polymerization formula of the conjugated diene polymer P and the properties of the obtained hydrogenated conjugated diene polymer P are shown in Table 1 below.

[Synthesis Example 2 to Synthesis Example 6] The hydrogenated conjugated diene polymer Q to polymer was obtained in the same manner as in the above Synthesis Example except that the hydrogenation ratio was changed as described in the following Table 1. U. The properties of the obtained conjugated diene polymer Q to polymer U are shown together in Table 1 below.

[Synthesis Example 7] Polymerization of styrene and 1,3-butadiene was carried out by the same operation as in Synthesis Example 1, and [N,N-bis(trimethyldecyl)aminopropyl]- The terminal modification of bis-ethoxy decane. Then, the solvent was removed by steam stripping (steam temperature: 190 ° C) for 2 hours at a temperature of the liquid phase of the desolventizing tank at 95 ° C, and dried by a hot roll adjusted to 110 ° C. This obtained a conjugated diene polymer V. The weight average molecular weight of the polymer was measured by GPC and found to be 200,000. The polymerization formulation of the conjugated diene polymer V and the properties of the obtained conjugated diene polymer V are shown in Table 1 below.

[Synthesis Example 8] The amount of n-butyllithium used was changed to 11.35 g, the amount of ruthenium tetrachloride used was changed to 2.32 g, and [N,N-bis(trimethyldecyl)aminopropyl group was added. Polymerization and terminal modification were carried out by the same procedure as in Synthesis Example 1, except that the amount of methyldiethoxydecane used was changed to 27.4 g. The reaction solution was set to 80 ° C or higher, and hydrogen was introduced into the system, after which, [bis(η5-cyclopentadienyl)titanium (fluorenyloxy) chloride] 2.76 g, diethyl chloride was added. 2.83 g of aluminum and 0.97 g of ruthenium tetrachloride were reacted so that the hydrogen pressure was 0.7 MPa or more until the hydrogenation rate became 70%. After reaching the flow rate of the predetermined amount of hydrogen, the reaction solution was returned to normal temperature and normal pressure, and extracted from the reaction vessel to obtain a polymer solution. The weight average molecular weight of the polymer was measured by GPC and found to be 50,000. Then, the solvent was removed by steam stripping (steam temperature: 190 ° C) for 2 hours at a temperature of the liquid phase of the desolventizing tank at a temperature of 95 ° C, and dried at 110 ° C, thereby obtaining a low molecular weight (5). The conjugated diene polymer W having a hydrogenation rate of 70%. The polymerization formula of the conjugated diene polymer W and the properties of the obtained conjugated diene polymer W are shown in Table 1 below.

[Synthesis Example 9 and Synthesis Example 10] The hydrogenated conjugated diene polymer X was obtained in the same manner as in the above Synthesis Example 1, except that the polymerization formula was changed as described in the following Table 1. Ytene-based polymer Y. The properties of the obtained conjugated diene polymer X and conjugated diene polymer Y are shown together in Table 1 below.

[Table 1]

In Table 1, the terminating modifier is abbreviated as follows. "-" means that the compound in this column is not used. Decane compound A: [N,N-bis(trimethyldecyl)aminopropyl]methyldiethoxydecane decane compound B: 1-[3-(triethoxydecyl)propyl]- 4-methylpiperazine

[Example 1] (1) Production of a rubber composition and a crosslinked rubber A conjugated diene polymer Q having a hydrogenation ratio of 60% obtained in the above Synthesis Example 2 was used as a polymer ( A) and the conjugated diene polymer V having a hydrogenation ratio of 0% obtained in the above Synthesis Example 7 as the polymer (B), each component was prepared by the formulation shown in Table 2 below. The compounding was carried out and kneaded to thereby produce a rubber composition. The following methods are used for kneading. A plastomill with a temperature control device (content: 250 ml) was used as the first stage of mixing (A training), and the polymer was formulated at a filling rate of 72% and a rotation speed of 60 rpm. (A), polymer (B), cerium oxide, decane coupling agent, extender oil, stearic acid, zinc oxide, and an anti-aging agent are kneaded. Then, as the second stage of kneading (B training), after the obtained preparation was cooled to room temperature, a vulcanization accelerator and sulfur were blended and kneaded. This was molded, and vulcanization molding was carried out at 160 ° C (crosslinking temperature) by a vulcanizing press for a predetermined period of time to obtain a crosslinked rubber.

(2) Evaluation of co-vulcanization property The rubber composition produced in the above (1) was used as a sample for measurement, and a co-vulcanization test was carried out to evaluate the co-vulcanizability of the polymer component in the rubber composition. The co-vulcanization test was carried out using a firmlastometer 7 (trade name) manufactured by JSR trading. First, after heating the die to 160 ° C, 6 g of the sample for measurement was placed in a mold, and the temperature was set to 160 ° C, the pressure was 490 kPa, the amplitude angle was ±1°, the torsional vibration number was 100 cpm, and the vulcanization time was 30. The minimum torque ML [dN-m] and the maximum torque MH [dN-m] are obtained from the vulcanization hardening curve at the minute, and the torque difference MH-MLΔ [dN- obtained by subtracting the minimum torque ML from the maximum torque MH is obtained. m]. In the sample, ML = 3.2, MH = 18.3, and MH - ML Δ = 15.1 (refer to Table 2 below). In addition, a rubber composition was produced in the same manner as in the above (1) except that the blending component of the polymer V was replaced with the polymer Q (all of the polymer components were the polymer Q). The rubber composition was subjected to a co-vulcanization test in the same manner as in the above (2). As a result, in the sample in which the polymer component was individually used as the polymer Q, ML = 3.2, MH = 20.5, and MH - ML Δ = 17.3 (refer to Table 4 below and Reference Example 1). In the same manner, a rubber composition was produced in the same manner as in the above (1), except that the blending component of the polymer Q was replaced with the polymer V (all of the polymer components were the polymer V). The rubber composition was subjected to a co-vulcanization test in the same manner as in the above (2). As a result, in the sample in which the polymer component was individually used as the polymer V, ML = 3.1, MH = 17.4, and MH - ML Δ = 14.3 (see Table 4 below and Reference Example 5). Using these data, the value of the co-vulcanization parameter was calculated by the above formula (1), and as a result, it was 0.97 in this example. Co-vulcanization parameter=15.1/(17.3×0.4+14.3×0.6)=0.97

(3) Evaluation of tensile strength The obtained crosslinked rubber was used as a sample for measurement, and tensile strength (TB (tensile strength) [MPa]) and elongation at break (EB) at break were measured in accordance with JIS K6251:2010. (elongation at break) [%]). The measurement results show that the larger the value of TB, the more difficult it is to break and the higher the mechanical strength, and the larger the value of EB, the larger the elongation (viscoelasticity) and the better. The results are shown in Table 2 below.

[Examples 2 to 13 and Comparative Examples 1 to 3 and Comparative Example 5] In the same manner as in the above-described Example 1, except that the formulation was changed as described in Tables 2 and 3 below. A rubber composition is produced and subjected to a crosslinking treatment to produce a crosslinked rubber. Further, the obtained rubber composition and crosslinked rubber were used, and physical properties were evaluated in the same manner as in Example 1. The results of these are shown in Tables 2 and 3 below. [Comparative Example 4] A rubber composition was produced in the same manner as in Example 1 except that the formulation was changed as described in the following Table 3. The crosslinking treatment was carried out at 200 ° C to produce cross-linking. rubber. Further, the obtained rubber composition and crosslinked rubber were used, and physical properties were evaluated in the same manner as in Example 1. Further, the measurement temperature of the co-sulfidability test was set to 200 °C. The results of these are shown in Table 3 below.

[Table 2]

[table 3]

In Tables 2 and 3, the product names used for each component are as follows (the same applies to Tables 4 and 5 below). "-" means a compound that does not use this column. *1: ZEOSIL 1165MP manufactured by Rhodia, *2: Si75, *3 manufactured by Evonik: NXT Z45, *4 manufactured by Momentive :Seast KH*5 manufactured by Tokai Carbon: T-DAE (Treated Distillate Aromatic Extract) manufactured by JX Nippon Mining & Energy Co., Ltd., *6: Ozono manufactured by Seiko Chemical Co., Ltd. (Ozonone) 6C, *7: Nocceler CZ, *8 manufactured by Ouchi Shinko Chemical Industry Co., Ltd.: Nocceler CZ-G, *9 manufactured by Ouchi Shinko Chemical Industry Co., Ltd.: Nocceler D, *10 manufactured by Ouchi Shinko Chemical Industry Co., Ltd.: Axell LUR manufactured by Kawaguchi Chemical Industry Co., Ltd.

According to the results of Tables 2 and 3, the rubber compositions of the two conjugated diene polymers having different hydrogenation rates were used, and Examples 1 to 13 and Comparative Examples 1 to 5 were used. In comparison, a good tensile strength (TB) and elongation at break (EB) are exhibited in a balanced manner, so that a high-strength crosslinked rubber can be obtained. From the results of these, it can be said that the rubber composition of the embodiment can produce a high-strength rubber at a low price.

[Reference Example 1 to Reference Example 19] A rubber composition was produced in the same manner as in Example 1 except that the formulation was changed as shown in Tables 4 and 5 below, and the crosslinking treatment was performed. Manufacture of crosslinked rubber. Further, physical properties were evaluated in the same manner as in Example 1 except that the obtained rubber composition and crosslinked rubber were used. In Reference Example 15 and Reference Example 16, the production temperature (crosslinking temperature) of the crosslinked rubber and the measurement temperature of the co-sulfidability test were set to 200 °C. The results of these are shown in Tables 4 and 5 below.

[Table 4]

[table 5]

no

no

Claims (5)

A crosslinked rubber which is a crosslinked rubber obtained by crosslinking a rubber composition, the rubber composition comprising: (A) a hydrogenated conjugated diene polymer which is polymerized by gel permeation chromatography The weight average molecular weight in terms of styrene is 1.0 × 10 ⁵ to 2.0 × 10 ⁶ , and has a structural unit derived from butadiene, and is a structural unit represented by the following formula (2), and the following formula (3) When the structural ratios of the structural unit, the structural unit represented by the following formula (4), and the structural unit represented by the following formula (5) are p, q, r, and s, respectively, the following formula is satisfied ( 6); 0.60≦(p+r)/(p+q+r+s)≦0.90 (6) (B) a hydrogenated or unhydrogenated conjugated diene polymer having a structural unit derived from butadiene and having a hydrogenation ratio different from that of the component (A); (C) cerium oxide; and (D) crosslinking a co-vulcanization parameter represented by the following formula (1) in the rubber composition is 0.85 or more; co-vulcanization parameter=X/(Y×α+Z×β) (1) In 1), α is a content ratio of the component (A) relative to the total amount of the component (A) and the component (B) in the rubber composition, and β is relative to the The content ratio of the component (B) in the total amount of the component (A) and the component (B) in the rubber composition satisfies the relationship of α + β = 1; X is the rubber from the rubber The composition was used as a sample, and the minimum torque was subtracted from the maximum torque measured within 30 minutes by the vibration type vulcanization tester at a cross-linking temperature and an amplitude angle of ±1° and a torsional vibration number of 100 cpm. The obtained torque difference, Y, is obtained by replacing the component (B) in the rubber composition with the component (A) as a sample. The torque difference, Z, is the torque difference when the component (A) in the rubber composition is replaced with the component (B) as a sample. The crosslinked rubber according to claim 1, wherein the component (B) is such that (p+r)/(p+q+r+s) of the component (A) is θ. A hydrogenated or unhydrogenated conjugated diene polymer satisfying the following formula (7); 0 ≦ (p + r) / (p + q + r + s) < θ (7). The crosslinked rubber according to claim 1, wherein at least one of the component (A) and the component (B) has a group selected from an amine group at both ends or both ends of the polymer. One or more functional groups in the group consisting of a carbon-nitrogen double bond group, a nitrogen-containing heterocyclic group, a phosphino group, a thiol group, and a hydrocarbyloxyalkyl group. The crosslinked rubber according to the first aspect of the invention, wherein the (B) component has a polystyrene-equivalent weight average molecular weight by gel permeation chromatography of 1.0 × 10 ⁵ to 2.0 × 10 ⁶ . A tire having at least a tread or a sidewall formed by the crosslinked rubber according to any one of claims 1 to 4.