WO2017086208A1

WO2017086208A1 - Production method for hydrogenated conjugated diene polymer, hydrogenated conjugated diene polymer, polymer composition, crosslinked polymer, and tire

Info

Publication number: WO2017086208A1
Application number: PCT/JP2016/083088
Authority: WO
Inventors: 拓海足立; 寛文千賀; 貴臣松本; 了司田中; 郁宏豊川; 直矢野坂
Original assignee: Jsr株式会社
Priority date: 2015-11-17
Filing date: 2016-11-08
Publication date: 2017-05-26

Abstract

A hydrogenated conjugated diene polymer produced by a method comprising the steps of: polymerizing, in the presence of an alkali metal compound or the like, monomers including butadiene to obtain a conjugated diene polymer having an active terminal; reacting the conjugated diene polymer having an active terminal with a compound represented by formula (1); and performing hydrogenation such that the degree of hydrogenation of the butadiene-derived structural unit in the conjugated diene polymer is 80-99%. In formula (1), X¹ is a silicon atom or a nitrogen atom, R¹ is a single bond or an alkanediyl group, R² is an alkanediyl group, R³ is a hydrocarbyl group, A¹ is a hydrocarbyl group or a group represented by "-R⁴-A²", and B¹ is a substituted or unsubstituted hydrocarbyl group or the like.

Description

Method for producing hydrogenated conjugated diene polymer, hydrogenated conjugated diene polymer, polymer composition, crosslinked polymer and tire

The present disclosure relates to a method for producing a hydrogenated conjugated diene polymer, a hydrogenated conjugated diene polymer, a polymer composition, a crosslinked polymer, and a tire.

A conjugated diene polymer obtained by polymerization using a conjugated diene compound has good properties such as heat resistance, wear resistance, mechanical strength, and moldability, so that a pneumatic tire, a vibration-proof rubber, Widely used in various industrial products such as hoses.

For example, rubber compositions used for pneumatic tire treads and sidewalls should contain a reinforcing agent such as carbon black or silica together with a conjugated diene polymer in order to improve the durability and wear resistance of the tire. Is known (see, for example, Patent Document 1). Conventionally, a conjugated diene polymer obtained by modifying the terminal of a conjugated diene polymer with a functional group is blended in a rubber composition. End-modified conjugated diene polymers have better compatibility with reinforcing agents such as carbon black and silica compared to unmodified conjugated diene rubbers. Can be improved. In recent years, it has been proposed to obtain a tire member having high strength and low wear by using a hydrogenated product of a modified conjugated diene polymer having a specific functional group at one or both ends (Patent Document 2). reference).

Japanese Patent Laid-Open No. 2004-18795 International Publication No. 2014/133097

In recent years, rubber materials have a high fracture strength, low hysteresis loss characteristics, wet characteristics due to environmental conditions such as global warming due to carbon dioxide emissions, increased awareness of resource and energy savings, and economic conditions such as rising gasoline prices. Further improvement of various characteristics such as grip characteristics and wear resistance is required.

The present disclosure has been made in view of the above problems, and provides a hydrogenated conjugated diene polymer capable of obtaining a rubber material having improved fracture strength, low hysteresis loss characteristics, wet grip characteristics, and wear resistance in a well-balanced manner. One purpose is to do.

According to the present disclosure, the following method for producing a hydrogenated conjugated diene polymer, a hydrogenated conjugated diene polymer, a polymer composition, a crosslinked polymer, and a tire are provided.

[1] A method for producing a hydrogenated conjugated diene polymer, which is a hydrogenated product of a conjugated diene polymer having a structural unit derived from butadiene, comprising at least one of an alkali metal compound and an alkaline earth metal compound The step of polymerizing the monomer containing butadiene in the presence to obtain the conjugated diene polymer having an active end, the conjugated diene polymer having the active end, and the following formula (1) A hydrogenated conjugated diene system comprising: a step of reacting with a compound; and a hydrogenation step so that a hydrogenation rate of the structural unit derived from the butadiene of the conjugated diene polymer is 80 to 99%. A method for producing a polymer.

(In Formula (1), X ¹ is a silicon atom or a nitrogen atom, R ¹ is a single bond or an alkanediyl group, R ² is an alkanediyl group, and R ³ is a hydrocarbyl group. ¹ is a hydrocarbyl group or a group represented by “—R ⁴ -A ² ”, provided that when k = 0, A ¹ is a group having a hydrocarbyloxysilyl group, and B ¹ is X ¹ In the case of a silicon atom, the ring has a hydrocarbyl group, a group represented by “—R ⁴ —A ² ”, or at least one atom selected from the group consisting of nitrogen, phosphorus, oxygen and sulfur, and A monovalent cyclic group having no active hydrogen, and when X ¹ is a nitrogen atom, a hydrocarbyl group, a group represented by “—R ⁴ -A ² ”, a trihydrocarbylsilyl group, or nitrogen, phosphorus Selected from the group consisting of oxygen and sulfur At least have one atom in the ring that, and a monovalent cyclic group having no active hydrogen .R ⁴ is a hydrocarbylene group, A ² is nitrogen, oxygen, phosphorus, sulfur and silicon A monovalent functional group having at least one atom selected from the group consisting of, having no active hydrogen, and bonded to R ⁴ with nitrogen, oxygen, phosphorus, sulfur or silicon, wherein R ³ , When a plurality of R ⁴ and A ² are present, they may be the same or different from each other, j and k are integers, provided that when X ¹ is a silicon atom, k is 1 or 2, and j + k = 2 and when X ¹ is a nitrogen atom, j = 1 and k = 0.)
[2] A hydrogenated conjugated diene polymer, which is a hydrogenated product of a conjugated diene polymer having a structural unit derived from butadiene, having a structural unit derived from the butadiene and having an alkali at the end of the polymer A reaction product of a conjugated diene polymer having a metal or an alkaline earth metal and the compound represented by the above formula (1), and a structural unit derived from the butadiene of the conjugated diene polymer. A hydrogenated conjugated diene polymer having a hydrogenation rate of 80 to 99%.
[3] A polymer composition comprising the hydrogenated conjugated diene polymer obtained by the production method of [1] or the hydrogenated conjugated diene polymer of [2], silica, and a crosslinking agent.
[4] A crosslinked polymer obtained by crosslinking the polymer composition of [3].
[5] A tire using the cross-linked polymer of [4] above as at least a tread or sidewall material.

According to the present disclosure, it is possible to obtain a rubber material having improved fracture strength, low hysteresis loss characteristics, wet grip characteristics, and wear resistance in a well-balanced manner.

The hydrogenated conjugated diene polymer of the present disclosure is a hydrogenated product of a conjugated diene polymer having a structural unit of a conjugated diene compound. The hydrogenated conjugated diene polymer is produced by a method including the following polymerization step, modification step and hydrogenation step. Hereinafter, matters related to aspects of the present disclosure will be described in detail.

<Polymerization process>
This step is a step of polymerizing a monomer containing butadiene to obtain a conjugated diene polymer having an active end. 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”) may be used in combination. Examples of other conjugated diene compounds include isoprene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 1,3-hexadiene, 1,3-heptadiene, and 2-phenyl-1,3-butadiene. , 3-methyl-1,3-pentadiene, 2-chloro-1,3-butadiene and the like. Of these, isoprene and 2,3-dimethyl-1,3-butadiene are preferred.

The conjugated diene polymer in the present disclosure may be a homopolymer using a conjugated diene compound, but is a copolymer of a conjugated diene compound and an aromatic vinyl compound from the viewpoint of increasing rubber strength. Is preferred. Examples of the aromatic vinyl compound used for polymerization include styrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, α-methylstyrene, 2,4-dimethylstyrene, 2,4-diisopropylstyrene, 4 -T-butylstyrene, 5-t-butyl-2-methylstyrene, vinylethylbenzene, divinylbenzene, trivinylbenzene, divinylnaphthalene, t-butoxystyrene, vinylbenzyldimethylamine, (4-vinylbenzyl) dimethylaminoethyl ether N, N-dimethylaminoethylstyrene, N, N-dimethylaminomethylstyrene, 2-ethylstyrene, 3-ethylstyrene, 4-ethylstyrene, 2-t-butylstyrene, 3-t-butylstyrene, 4- t-butyl styrene, vinyl xylene, Sulfonyl naphthalene, vinyl pyridine, diphenylethylene, tertiary amino group-containing diphenylethylene (e.g., 1- (4-N, N- dimethylaminophenyl) -1-phenylethylene, etc.) and the like. Of these, styrene and α-methylstyrene are preferable as the aromatic vinyl compound.

When the conjugated diene polymer in the present disclosure is a copolymer of a conjugated diene compound and an aromatic vinyl compound, 1,3-butadiene and styrene are included in the monomer composition in terms of high living property in anionic polymerization. A polymer is preferred. The copolymer preferably has a random copolymer portion in which the distribution of the conjugated diene compound and the aromatic vinyl compound is irregular, and further has a block portion made of the conjugated diene compound or the aromatic vinyl compound. It may be.

When the conjugated diene polymer is a copolymer of a conjugated diene compound and an aromatic vinyl compound, the proportion of the aromatic vinyl compound used is a balance between the low hysteresis loss characteristics and wet grip characteristics of the resulting crosslinked polymer. From this point of view, it is preferably 3 to 55% by mass, more preferably 5 to 50% by mass, based on the total amount of the conjugated diene compound and the aromatic vinyl compound used in the polymerization. The content ratio of the structural unit derived from the aromatic vinyl compound in the polymer is a value measured by ¹ H-NMR. A conjugated diene compound and an aromatic vinyl compound may be used individually by 1 type, respectively, and may be used in combination of 2 or more type.

In 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 other monomers include acrylonitrile, methyl (meth) acrylate, ethyl (meth) acrylate, and the like. The proportion of other monomers used is preferably 25% by mass or less, more preferably 15% by mass or less, and more preferably 10% by mass or less, based on the total amount of monomers used for polymerization. preferable.

As the polymerization method to be used, any of solution polymerization method, gas phase polymerization method and bulk polymerization method may be used, but the solution polymerization method is particularly preferable. Moreover, as a polymerization form, you may use any of a batch type and a continuous type. When using the solution polymerization method, as an example of a specific polymerization method, a monomer containing a conjugated diene compound is polymerized in an organic solvent in the presence of a polymerization initiator and a randomizer used as necessary. The method of doing is mentioned.

As the polymerization initiator, at least one of an alkali metal compound and an alkaline earth metal compound can be used. Specific examples thereof include, for example, methyllithium, ethyllithium, n-propyllithium, n-butyllithium, sec-butyllithium, alkyllithium such as t-butyllithium, 1,4-dilithiobutane, phenyllithium, stilbenelithium, Naphthyl lithium, 1,3-bis (1-lithio-1,3-dimethylpentyl) benzene, 1,3-phenylenebis (3-methyl-1-phenylpentylidene) dilithium, naphthyl sodium, naphthyl potassium, di-n -At least one of butyl magnesium, di-n-hexyl magnesium, ethoxy potassium, calcium stearate, alkali metal compound and alkaline earth metal compound and a compound having a functional group that interacts with silica (modifier) Compound obtained Etc. The. As the polymerization initiator, lithium compounds are particularly preferable. The total amount of the polymerization initiator used is preferably 0.2 to 20 mmol with respect to 100 g of the monomer used for the polymerization.

In the polymerization reaction, by performing polymerization in the presence of a compound obtained by mixing at least one of an alkali metal compound and an alkaline earth metal compound with a compound having a functional group that interacts with silica (modifier). The polymerization initiation terminal of the conjugated diene polymer can be modified with a functional group that interacts with silica. In the present specification, the “functional group that interacts with silica” means a group having an element that interacts with silica, such as nitrogen, sulfur, phosphorus, and oxygen. “Interaction” refers to an intermolecular force that forms a covalent bond between molecules or is weaker than a covalent bond (eg, ion-dipole interaction, dipole-dipole interaction, hydrogen bond, van der Waals This means that an electromagnetic force between molecules such as force is formed.

Among them, nitrogen-containing compounds such as secondary amine compounds are preferable as the modifier used for modification of the polymerization initiation terminal. Specific examples of the nitrogen-containing compound include, for example, dimethylamine, diethylamine, dipropylamine, dibutylamine, dodecamethyleneimine, N, N′-dimethyl-N′-trimethylsilyl-1,6-diaminohexane, piperidine, pyrrolidine, Hexamethyleneimine, heptamethyleneimine, dicyclohexylamine, N-methylbenzylamine, di- (2-ethylhexyl) amine, diallylamine, morpholine, N- (trimethylsilyl) piperazine, N- (tert-butyldimethylsilyl) piperazine, 1, Examples include 3-ditrimethylsilyl-1,3,5-triazinane.

When modifying the starting terminal, at least one of an alkali metal compound and an alkaline earth metal compound and a compound having a functional group that interacts with silica are mixed in advance, and the mixture is added to the polymerization system. Polymerization may be performed. 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 silica may be added to the polymerization system, and polymerization may be performed by mixing both in the polymerization system. Good.

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

The organic solvent used for the polymerization may be an organic solvent inert to the reaction, and for example, aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons and the like can be used. Among these, hydrocarbons having 3 to 8 carbon atoms are preferable, and specific examples thereof include, for example, propane, n-butane, isobutane, n-pentane, isopentane, n-hexane, cyclohexane, propene, 1-butene and isobutene. , Trans-2-butene, cis-2-butene, 1-pentyne, 2-pentyne, 1-hexene, 2-hexene, benzene, toluene, xylene, ethylbenzene, heptane, cyclopentane, methylcyclopentane, methylcyclohexane, 1 -Pentene, 2-pentene, cyclohexene and the like. In addition, as an organic solvent, 1 type can be used individually or in combination of 2 or more types.

In the case of solution polymerization, the monomer concentration in the reaction solvent is preferably 5 to 50% by mass, and preferably 10 to 30% by mass from the viewpoint of maintaining a balance between productivity and ease of polymerization control. More preferred. The temperature of the polymerization reaction is preferably −20 ° C. to 150 ° C., more preferably 0 to 120 ° C. The polymerization reaction is preferably performed under a pressure sufficient to keep the monomer in a substantially liquid phase. Such a pressure can be obtained by a method such as pressurizing the inside of the reactor with a gas inert to the polymerization reaction.

By such a polymerization reaction, a conjugated diene polymer having an active end can be obtained. The weight average molecular weight (Mw) in terms of polystyrene by gel permeation chromatography (GPC) of the resulting conjugated diene polymer is preferably 1.0 × 10 ⁵ to 2.0 × 10 ⁶ . If the Mw is smaller than 1.0 × 10 ⁵ , the resulting vulcanized rubber tends to be reduced in tensile strength, fuel efficiency and wear resistance, and if larger than 2.0 × 10 ⁶ , the polymer The processability of the composition tends to decrease. More preferably, it is 1.2 × 10 ⁵ to 1.5 × 10 ⁶ , and still more preferably 1.5 × 10 ⁵ to 1.0 × 10 ⁶ .

With respect to the conjugated diene polymer having an active terminal, the vinyl bond content in the structural unit derived from butadiene is preferably 30 to 70% by mass, more preferably 33 to 67% by mass, and 35 to 65% by mass. % Is more preferable. If the vinyl bond content is less than 30 mol%, the grip characteristics tend to be low, and if it exceeds 70 mass%, the wear resistance of the resulting vulcanized rubber tends to decrease. Incidentally, "vinyl bond content" as used herein, the conjugated diene polymer, relative to the total structural units derived from butadiene, a value indicating the content of the structural unit having 1,2-coupled, ¹ H -Value measured by NMR.

<Modification process>
In this step, the active terminal of the conjugated diene polymer obtained above is reacted with the compound represented by the above formula (1) (hereinafter also referred to as “specific modifier”). By this reaction, a conjugated diene polymer that is end-modified with a specific modifier is obtained.

In the above formula (1), the alkanediyl group of R ¹ and R ² preferably has 1 to 3 carbon atoms, and more preferably 1 or 2 carbon atoms. Examples of the hydrocarbyl group of A ¹ , B ¹ , R ³ include, for example, a linear or branched alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, And an aralkyl group having 7 to 20 carbon atoms. R ³ is preferably an alkyl group. When k is 2, the plurality of R ³ may be the same as or different from each other.

A ¹ and B ¹ may be a substituted hydrocarbyl group in which a part of the hydrocarbyl group is substituted with a functional group having at least one atom selected from the group consisting of nitrogen, oxygen, phosphorus, sulfur and silicon. In the substituted hydrocarbyl group, examples of the functional group having at least one atom selected from the group consisting of nitrogen, oxygen, phosphorus, sulfur and silicon include —NR ⁵ R ⁶ , —PR ⁵ R ⁶ , —NR ⁵ —, — PR ⁵ — (wherein R ⁵ and R ⁶ are each independently a hydrocarbyl group having 1 to 10 carbon atoms), —O—, —S—, —S—S—, hydrocarbylsilyl group, hydrocarbyloxysilyl Groups and the like. Specific examples of the substituted hydrocarbyl group include a group represented by “—R ⁴ —A ² ” and an active hydrogen having at least one atom selected from the group consisting of nitrogen, phosphorus, oxygen and sulfur in the ring. And monovalent cyclic groups that do not have any. A group represented by “—R ⁴ -A ² ” is preferable.

R ⁴ 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 arylene group having 6 to 20 carbon atoms, more preferably an alkanediyl group. preferable.
As A ² , for example, a nitrogen-containing group in which two hydrogen atoms of a primary amino group are substituted with two protecting groups, a nitrogen-containing group in which one hydrogen atom of a secondary amino group is substituted with one protecting group Group, tertiary amino group, group having carbon-nitrogen double bond, nitrogen-containing heterocyclic group, phosphorus-containing group in which two hydrogen atoms of primary phosphino group are substituted by two protecting groups, secondary phosphino group A phosphorus-containing group in which one hydrogen atom is substituted with one protecting group, a tertiary phosphino group, and a sulfur-containing group in which one hydrogen atom of a thiol group is substituted with one protecting group, “—Si” (R ⁵ ) _m (OR ⁶ ) _3-m ”(wherein R ⁵ and R ⁶ are each independently a hydrocarbyl group, and m is an integer of 0 to 2). It is done. From the viewpoint of good affinity with silica, a group having a silicon atom or a nitrogen atom is particularly preferable. The protecting group is not particularly limited, and examples thereof include a trisubstituted hydrocarbylsilyl group. In the case where in the formula ^R 4, ^{A 2} there are a plurality, the plurality of ^R 4, ^{A 2} may be the same or different from each other.

When the substituted hydrocarbyl group is the above monovalent cyclic group, for example, one hydrogen atom from the ring portion of the heteroaromatic compound having at least one atom selected from the group consisting of nitrogen, phosphorus, oxygen and sulfur The removed group is mentioned. Examples of the heteroaromatic compound include pyridine, pyrimidine, pyrazine, thiophene, and furan.
Examples of the trihydrocarbylsilyl group for B ¹ include a trimethylsilyl group, a triethylsilyl group, a triisopropylsilyl group, a tert-butyldimethylsilyl group, and the like.

Preferable specific examples of the specific modifier include a compound represented by the following formula (1-1) and a compound represented by the following formula (1-2).

(In the formula (1-1), A ¹¹ is a hydrocarbyl group, B ¹¹ is a hydrocarbyl group or a group represented by “—R ⁴ -A ² ”, and n is 1 or 2. R ² , R ³ , R ⁴ and A ² have the same meanings as in the above formula (1).
In Formula (1-2), R ¹¹ is an alkanediyl group, A ¹² is a group represented by “—R ⁴ —Si (R ⁵ ) _m (OR ⁶ ) _3-m ”, and B ¹² is , A hydrocarbyl group, a group represented by “—R ⁴ -A ² ”, or a trihydrocarbylsilyl group. R ⁵ and R ⁶ are each independently a hydrocarbyl group, and m is an integer of 0-2. R ² , R ⁴ and A ² have the same meaning as in the above formula (1). )

In the above formulas (1-1) and (1-2), the description of the corresponding part of A ¹ is applied to A ¹¹ and A ¹² , and the corresponding part of B ¹ is applied to B ¹¹ and B ^12. The explanation of the part to be applied applies.
B ¹¹ is preferably a group represented by “—R ⁴ -A ² ” from the viewpoint of breaking strength and wet grip characteristics of the resulting crosslinked polymer, and A ² has a nitrogen atom or a silicon atom. A group is more preferable, and a group having a nitrogen atom is more preferable.
n is preferably 2.

Specific examples of the specific modifier include, for example, 2- (2,2-dimethoxy-1,2-azasilolidin-1-yl) -N, N-diethylethane as the compound represented by the above formula (1-1). -1-amine, 2- (2,2-diethoxy-1,2-azacylolidine-1-yl) -N, N-diethylethane-1-amine, 2- (2,2-dimethoxy-1,2-azacylolidine -1-yl) -N, N-dimethylethane-1-amine, 3- (2,2-dimethoxy-1,2-azasilolidin-1-yl) -N, N-diethylpropan-1-amine, 2, 2-dimethoxy-1- (3-trimethoxysilylpropyl) -1,2-azasilolidine, 2,2-diethoxy-1- (3-trimethoxysilylpropyl) -1,2-azasilolidine, 2,2-dimethoxy- 1- (3- Liethoxysilylpropyl) -1,2-azasilolidine, 2-methoxy-2-methyl-1- (3-trimethoxysilylpropyl) -1,2-azasilolidine, 2,2-dimethoxy-1-phenyl-1,2 -Azasilolidine etc .;
Examples of the compound represented by the above formula (1-2) include 1- [3- (triethoxysilyl) propyl] -4-trimethylsilylpiperazine, 1- [3- (trimethoxysilyl) propyl] -4-trimethylsilylpiperazine. 1,4-bis [3- (triethoxysilyl) propyl] piperazine, 1,4-bis [3- (trimethoxysilyl) propyl] piperazine, 1,3-bis [3- (triethoxysilyl) propyl] Imidazolidine, 1,3-bis [3- (triethoxysilyl) propyl] hexahydropyrimidine, 1,3-bis [3- (trimethoxysilyl) propyl] -1,2,3,4-tetrahydropyrimidine, etc. , Can be mentioned respectively. In addition, a specific modifier may be used individually by 1 type, and 2 or more types may be mixed and used for it.

In terminal modification of the conjugated diene polymer, only the specific modifier may be used, but other modifiers may be used together with the specific modifier. The other modifier is not particularly limited as long as it is a compound that can react with the active terminal of the polymer, and a known compound can be used as the modifier, and specifically, for example, a functional group that interacts with silica. And the like, coupling agents and the like. When using other modifiers, the proportion of use is 20 with respect to the total amount of the specific modifier and the other modifier from the viewpoint of sufficiently proceeding the reaction between the conjugated diene polymer and the specific modifier. It is preferable to set it as mol% or less, and it is more preferable to set it as 10 mol% or less.

The reaction between the conjugated diene polymer having an active terminal and the specific modifier can be performed as a solution reaction, for example. This solution reaction may be carried out using a solution containing unreacted monomers after the completion of the polymerization reaction. The conjugated diene polymer contained in the solution is isolated and dissolved in a suitable solvent such as cyclohexane. You may go. Further, the denaturation reaction may be performed using either a batch system or a continuous system. At this time, the addition method of the modifier is not particularly limited, and examples thereof include a batch addition method, a division addition method, and a continuous addition method.

The use ratio of the specific modifier (the total amount when two or more are used) is preferably 0.2 mol or more with respect to 1 mol of the metal atom involved in the polymerization reaction of the polymerization initiator, More preferably, it is 0.4 mol or more. By setting it as 0.2 mol or more, the modification reaction by the specific modifier progresses sufficiently, and the effect of improving the dispersibility of the filler can be sufficiently enhanced. Moreover, the upper limit of the usage rate of a specific modifier is 1.5 with respect to 1 mol of metal atoms which a polymerization initiator has in terms of reducing unreacted substances in the solution after the modification reaction. The amount is preferably less than mol, and more preferably less than 1.2 mol.

The temperature of the modification reaction is usually the same as the temperature of the polymerization reaction, preferably −20 ° C. to 150 ° C., more preferably 0 to 120 ° C. When the temperature of the modification reaction is low, the viscosity of the conjugated diene polymer after modification tends to increase. On the other hand, when the temperature of the modification reaction is high, the polymerization active terminal tends to be deactivated. The reaction time of the denaturation reaction is preferably 1 minute to 5 hours, more preferably 2 minutes to 1 hour.

<Hydrogenation process>
In this step, the butadiene portion of the conjugated diene polymer obtained by the modification reaction is hydrogenated (hydrogenated). As a result, a hydrogenated conjugated diene polymer that has been end-modified with a specific modifier is obtained.

As the hydrogenation method and conditions, any method and conditions can be used as long as a polymer having a desired hydrogenation rate can be obtained. Examples of such hydrogenation methods include a method in which a catalyst mainly composed of an organometallic compound of titanium is used as a hydrogenation catalyst, and a catalyst comprising an organometallic compound of iron, nickel, cobalt and an organometallic compound such as alkylaluminum. Method of using, method of using an organic complex of an organometallic compound such as ruthenium, rhodium, method of using a catalyst in which a metal such as palladium, platinum, ruthenium, cobalt or nickel is supported on a carrier such as carbon, silica or alumina and so on. Among various methods, a homogeneous catalyst composed of an organometallic compound of titanium alone or an organometallic compound of lithium, magnesium, and aluminum (Japanese Patent Publication No. 63-4841 and Japanese Patent Publication No. 1-337970) is used. The hydrogenation method under mild conditions of low pressure and low temperature is industrially preferable, and the hydrogenation selectivity to the double bond derived from butadiene is high, which is suitable for the purpose of the present disclosure.

Hydrogenation is carried out in a solvent that is inert to the catalyst and in which the conjugated diene polymer is soluble. Preferred solvents include aliphatic hydrocarbons such as n-pentane, n-hexane and n-octane, alicyclic hydrocarbons such as cyclohexane and cycloheptane, aromatic hydrocarbons such as benzene and toluene, diethyl ether , Ethers such as tetrahydrofuran alone or a mixture containing them as a main component.

In the hydrogenation reaction, the polymer is generally held at a predetermined temperature in hydrogen or an inert atmosphere, a hydrogenation catalyst is added with stirring or under stirring, and hydrogen gas is then introduced to increase the pressure. It is carried out by pressing. The inert atmosphere means an atmosphere that does not react with a participant in the hydrogenation reaction, and is formed of helium, neon, argon, or the like. Air or oxygen is not preferable because it oxidizes the catalyst and deactivates the catalyst. Nitrogen is not preferred because it acts as a catalyst poison during the hydrogenation reaction and reduces the hydrogenation activity. In particular, the hydrogenation reactor preferably has an atmosphere of hydrogen gas alone. As a hydrogenation reaction process for obtaining a hydrogenated conjugated diene polymer, any of a batch process, a continuous process, and a combination thereof may be used. The addition amount of the hydrogenation catalyst is preferably 0.02 to 20 mmol per 100 g of the conjugated diene polymer before hydrogenation.

The hydrogenation rate of the hydrogenated conjugated diene polymer of the present disclosure is in the range of 80 to 99%. By setting the hydrogenation rate to 80% or more, it is possible to obtain a rubber having a sufficiently high effect of improving the breaking strength and the abrasion resistance when the crosslinked polymer is used. The hydrogenation rate is more preferably 85% or more, further preferably 90% or more, and particularly preferably 92% or more. Further, the upper limit of the hydrogenation rate is 99% or less, preferably 98% or less, more preferably 97% or less, from the viewpoint of reducing the production efficiency. The hydrogenation rate is a value measured by ¹ H-NMR. The hydrogenation rate can be selected as desired by changing the amount of the hydrogenation catalyst, the hydrogen pressure during the hydrogenation reaction, and the reaction time.

The hydrogenated conjugated diene polymer of the present disclosure includes a structural unit represented by the following formula (3), a structural unit represented by the following formula (4), a structural unit represented by the following formula (5), and the following: When the constitutional ratio of the structural unit represented by the formula (6) is p, q, r, and s, the polymer satisfies the following formula (A).
0.80 ≦ (p + r) / (p + q + r + s) ≦ 0.99 (A)

The above formula (A) represents that “the hydrogenation rate of the structural unit derived from butadiene is 80 to 99%”. The vinyl bond content (%) of the hydrogenated conjugated diene polymer of the present disclosure is represented by “[(p + q) / (p + q + r + s)] × 100”.

A preferred method for obtaining the hydrogenated conjugated diene-based polymer of the present disclosure is a solution polymerization of a monomer containing butadiene in the presence of an alkali metal compound, a modification step is performed using the obtained polymer solution as it is, and then It is used for the hydrogenation process and is industrially useful. The hydrogenated conjugated diene polymer of the present disclosure can be obtained by removing the solvent from the solution obtained above and isolating the polymer. The polymer can be isolated by a known desolvation method such as steam stripping and a drying operation such as heat treatment. The weight average molecular weight (Mw) in terms of polystyrene by GPC of the resulting hydrogenated conjugated diene polymer is preferably 1.0 × 10 ⁵ to 2.0 × 10 ⁶ , more preferably 1.2 × 10 6. ⁵ to 1.5 × 10 ⁶ , more preferably 1.5 × 10 ⁵ to 1.0 × 10 ⁶ .

<Polymer composition>
The polymer composition of the present disclosure contains the hydrogenated conjugated diene polymer, silica, and a crosslinking agent. The content ratio of the hydrogenated conjugated diene polymer in the polymer composition is preferably 20% by mass or more, more preferably 30% by mass or more with respect to the total amount of the polymer composition. More preferably, it is 40% by mass or more.

Examples of silica include wet silica (hydrous silicic acid), dry silica (anhydrous silicic acid), colloidal silica, precipitated silica, calcium silicate, and aluminum silicate. Of these, wet silica is particularly preferred from the viewpoint of the effect of improving the fracture resistance and the effect of achieving both wet grip properties and low rolling resistance. It is also preferable to use high dispersible type silica from the viewpoint of improving dispersibility in the polymer composition and improving physical properties and processability. In addition, a silica can be used individually by 1 type or in combination of 2 or more types.

The polymer composition may contain various reinforcing fillers such as carbon black, clay and calcium carbonate in addition to silica as a filler. Preferably, silica or a combination of carbon black and silica is used. The total amount of silica and carbon black in the polymer composition is preferably 20 to 130 parts by mass, more preferably 25 to 110 parts per 100 parts by mass of the total amount of polymer components contained in the polymer composition. Part by mass.

Examples of the crosslinking agent include sulfur, sulfur halides, organic peroxides, quinonedioximes, organic polyvalent amine compounds, alkylphenol resins having a methylol group, and sulfur is usually used. The amount of sulfur is preferably 0.1 to 5 parts by mass, more preferably 0.5 to 3 parts by mass with respect to 100 parts by mass of the total amount of polymer components contained in the polymer composition.

The polymer composition of the present disclosure may contain other rubber components in addition to the hydrogenated conjugated diene polymer. The type of the rubber component is not particularly limited, but butadiene rubber (BR, such as high cis BR having 90% or more of cis-1,4 bond, BR containing syndiotactic-1,2-polybutadiene (SPB), etc.), styrene Examples thereof include butadiene rubber (SBR), natural rubber (NR), isoprene rubber (IR), styrene isoprene copolymer rubber, and butadiene isoprene copolymer rubber, and BR and SBR are more preferable.

In the polymer composition, in addition to the above-described components, for example, anti-aging agent, zinc white, stearic acid, softener, sulfur, vulcanization accelerator, silane coupling agent, compatibilizing agent, vulcanization aid, Various additives generally used in rubber compositions for tires, such as processing aids, process oils, and scorch inhibitors, can be blended. These blending ratios can be appropriately selected according to various components within a range not impairing the effects of the present disclosure.

In the polymer composition of the present disclosure, in addition to the polymer component and the cross-linking agent, components to be blended as necessary may be an open kneader (for example, a roll), a closed kneader (for example, a Banbury mixer), or the like. It can be applied to various rubber products as a crosslinked polymer by being kneaded using a kneader and crosslinked (vulcanized) after molding. Specifically, for example, tire applications such as tire treads, under treads, carcass, sidewalls, and bead parts; seal materials such as packings, gaskets, weather strips, O-rings; various vehicles such as automobiles, ships, aircraft, and railways Interior and exterior skin materials for building; building materials; anti-vibration rubber for industrial machinery and equipment; various hoses and hose covers such as diaphragms, rolls, radiator hoses and air hoses; belts such as power transmission belts; Dust boots; Medical equipment materials; Fenders; Wire insulation materials; Other industrial products. In particular, the vulcanized rubber obtained using the hydrogenated conjugated diene polymer of the present disclosure is excellent in wet skid resistance, low hysteresis loss characteristics, and wear resistance, and is used as a material for tire treads and sidewalls. It can be used suitably.

The tire can be manufactured according to a conventional method. For example, the above polymer composition is mixed with a kneader and formed into a sheet, and is placed in a predetermined position according to a conventional method and vulcanized to form a tread rubber or sidewall rubber. can get.

Hereinafter, although concretely described based on examples, the present disclosure is not limited to these examples. In the examples and comparative examples, “parts” and “%” are based on mass unless otherwise specified. Moreover, the measuring method of various physical-property values is shown below.

[Bound styrene content (%)]: Determined by ¹ H-NMR measurement at 500 MHz.
[Vinyl bond content (%)]: The content of 1,2-vinyl bond in the polymer was determined by ¹ H-NMR at 500 MHz.
[Glass transition temperature (° C.)]: Measured according to ASTM D3418.
[Weight average molecular weight]: From the retention time corresponding to the peak of the maximum peak of the GPC curve obtained by using gel permeation chromatography (GPC) (HLC-8120GPC (trade name, manufactured by Tosoh Corporation)), polystyrene Calculated by conversion.
(GPC conditions)
Column; two brand names “GMHXL” (manufactured by Tosoh Corporation) Column temperature: 40 ° C.
Mobile phase; tetrahydrofuran flow rate; 1.0 ml / min sample concentration; 10 mg / 20 ml
[Mooney viscosity (ML1 + 4, 100 ° C.)]: Measured according to JIS K6300-1 using an L rotor under conditions of preheating for 1 minute, rotor operating time of 4 minutes, and temperature of 100 ° C.
[Hydrogenation rate (%)]: The hydrogenation rate of the structural unit derived from butadiene was determined by ¹ H-NMR at 500 MHz.

[Example 1]
<Synthesis and Evaluation of Hydrogenated Conjugated Diene Polymer A>
An autoclave reactor with an internal volume of 10 liters purged with nitrogen was charged with 5,000 g of cyclohexane, 70 g of tetrahydrofuran, 250 g of styrene and 730 g of 1,3-butadiene. After adjusting the temperature of the reactor contents to 10 ° C., a cyclohexane solution containing n-butyllithium (11.6 mmol) as a polymerization initiator was added to initiate polymerization. The polymerization was carried out under adiabatic conditions and the maximum temperature reached 85 ° C. When the polymerization conversion rate reached 99%, 20 g of 1,3-butadiene was added, and polymerization was further performed for 5 minutes to obtain a reaction liquid containing a polymer. Thereafter, 8.5 mmol of 2- (2,2-dimethoxy-1,2-azasilolidin-1-yl) -N, N-diethylethane-1-amine was added to the reaction solution and reacted for 30 minutes.
Next, the reaction solution was heated to 80 ° C. or higher to introduce hydrogen into the system. Next, 0.73 g of [bis (η5-cyclopentadienyl) titanium (furfuryloxy) chloride], 1.16 g of diethylaluminum chloride, and 0.27 g of n-butyllithium are added to maintain a hydrogen pressure of 1.0 MPa. For 1 hour. After the reaction, the reaction solution was returned to room temperature and normal pressure and extracted from the reaction vessel to obtain a polymer solution.
Next, 4.4 g of 2,6-di-tert-butyl-p-cresol is added to the obtained polymer solution, and the pH is 8.5 with ammonia (pH at 80 ° C. according to the glass electrode method, the same applies hereinafter). The aqueous solution (temperature: 80 ° C.) adjusted to 1 is put into a desolvation tank, and the above polymer solution is added (ratio of 200 parts by mass of the aqueous solution to 100 parts by mass of the polymer solution), and the liquid phase of the desolvation tank The solvent was removed by steam stripping (steam temperature: 190 ° C.) for 2 hours at a temperature of 95 ° C., and dried with a hot roll adjusted to 110 ° C. to obtain a hydrogenated conjugated diene polymer A. It was. The polymerization formulation of the hydrogenated conjugated diene polymer A is shown in Table 1 below, and the properties of the obtained hydrogenated conjugated diene polymer A are shown in Table 2 below.

<Production of polymer composition and crosslinked polymer, and evaluation of physical properties>
Using the hydrogenated conjugated diene polymer A obtained above, each component was blended according to the blending formulation shown in Table 3 below and kneaded to prepare a polymer composition. The kneading was performed by the following method. Using a plastmill (internal volume: 250 ml) with a temperature control device, as a first stage kneading, under conditions of a filling rate of 72% and a rotation speed of 60 rpm, hydrogenated conjugated diene polymer A, extending oil, silica, Carbon black, silane coupling agent, stearic acid, anti-aging agent and zinc oxide were blended and kneaded. Next, as the second stage kneading, the blend obtained above was cooled to room temperature, and then sulfur and a vulcanization accelerator were blended and kneaded. This was molded and vulcanized with a vulcanizing press at 160 ° C. for a predetermined time to obtain a crosslinked polymer. Using the obtained crosslinked polymer, physical property evaluations (1) to (4) representing the following tire performances were performed. The results are shown in Table 4 below.

(1) Tensile strength (breaking strength)
According to JISK6251: 2010, 100% modulus (M100), 300% modulus (M300) and tensile strength (TB) at the time of cutting were measured. A measurement result is shown by the index | exponent which set the following comparative examples 1 as 100, and shows that tensile strength (breaking strength) is so high that a numerical value is large, and it is favorable.
(2) 0 ° C. tan δ
ARES-RDA (manufactured by TA Instruments) was used, and measurement was performed under the conditions of a shear strain of 1.0%, an angular velocity of 100 radians per second, and 0 ° C. A measurement result is shown by the index | exponent which set the comparative example 1 to 100, and shows that a wet grip characteristic is so favorable that a numerical value is large.
(3) 50 ° C. tan δ
ARES-RDA (manufactured by TA Instruments) was used, and measurement was performed under the conditions of shear strain 1.0%, angular velocity 100 radians per second, and 50 ° C. The measurement results are shown as an index with Comparative Example 1 being 100, and the larger the value, the smaller the energy loss and the better the low hysteresis loss characteristic.
(4) Abrasion resistance A DIN abrasion tester (manufactured by Toyo Seiki Co., Ltd.) was used, and measurement was performed at 25 ° C. under a load of 10 N in accordance with JIS K 6264. The measurement results are shown as an index with Comparative Example 1 being 100, and the larger the value, the better the wear resistance.

[Examples 2 and 3]
By carrying out polymerization in the same manner as in Example 1 except that 8.4 mmol of piperidine was charged into an autoclave reactor with 5,000 g of cyclohexane, 70 g of tetrahydrofuran, 250 g of styrene and 730 g of 1,3-butadiene, and then hydrogenated. Hydrogenated conjugated diene polymers B and C were obtained (Table 1). In Example 3, the hydrogenation rate was lower than that in Example 1 (84%). The properties of the obtained hydrogenated conjugated diene polymers B and C are shown in Table 2 below. Further, each of hydrogenated conjugated diene polymers B and C was used to produce a polymer composition in the same manner as in Example 1 with the formulation shown in Table 3 below, and vulcanized to obtain a crosslinked polymer. The physical properties were evaluated. The results are shown in Table 4 below.

[Examples 4 to 6]
Polymerization was carried out in the same manner as in Example 1 except that the specific modifier used was changed to that shown in Table 1 below, followed by hydrogenation to obtain hydrogenated conjugated diene polymers D to F, respectively. It was. The properties of the resulting hydrogenated conjugated diene polymers D to F are shown in Table 2 below. Further, using each of the hydrogenated conjugated diene polymers D to F, a polymer composition was produced in the same manner as in Example 1 with the formulation shown in Table 3 below, and vulcanized to obtain a crosslinked polymer. The physical properties were evaluated. The results are shown in Table 4 below.

Comparative Example 1 [Synthesis of hydrogenated conjugated diene polymer R and evaluation thereof]
Polymerization was conducted in the same manner as in Example 1 except that 8.5 mmol of N, N-diethyl-3- (trimethoxysilyl) propan-1-amine was used as the other modifier in place of the specific modifier. Subsequently, hydrogenation was performed to obtain a hydrogenated conjugated diene polymer R (Table 1). The properties of the resulting hydrogenated conjugated diene polymer R are shown in Table 2 below. Further, using the hydrogenated conjugated diene polymer R, a polymer composition was produced in the same manner as in Example 1 with the formulation shown in Table 3 below, and vulcanized to obtain a crosslinked polymer to evaluate physical properties. Went. The results are shown in Table 4 below.

[Comparative Example 2 [Synthesis of hydrogenated conjugated diene polymer S and its evaluation]]
A hydrogenated conjugated diene polymer S was obtained by performing the same operation as in Example 1 except that the hydrogenation rate was set to 70%. The properties of the obtained hydrogenated conjugated diene polymer S are shown in Table 2 below. Further, using the hydrogenated conjugated diene polymer S, a polymer composition was produced in the same manner as in Example 1 with the formulation shown in Table 3 below, and vulcanized to obtain a crosslinked polymer to evaluate physical properties. Went. The results are shown in Table 4 below.

In Table 1, abbreviations of specific modifiers and other modifiers are as follows.
Modifier 1: 2- (2,2-dimethoxy-1,2-azasilolidin-1-yl) -N, N-diethylethane-1-amine Modifier 2: 2,2-dimethoxy-1- (3-tri Methoxysilylpropyl) -1,2-azasilolidine modifier 3: 2,2-dimethoxy-1-phenyl-1,2-azasilolidine modifier 4: 1- [3- (triethoxysilyl) propyl] -4-trimethylsilylpiperazine Modifier 5: N, N-diethyl-3- (trimethoxysilyl) propan-1-amine

(In the formula, “TMS” represents a trimethylsilyl group.)

In Table 3, the trade names used for each component are as follows.
* 1: JOMO process NC-140 manufactured by Japan Energy, * 2: ZEOSIL 1165MP manufactured by Rhodia, * 3: Diablack N339 manufactured by Mitsubishi Chemical, * 4: Si75 manufactured by Evonik, * 5: Ozonon 6C manufactured by Seiko Chemical * 6: Nouchira CZ * 7: Ouchi Shinsei Chemical Co., Ltd. Noxeller D

From the results in Table 4, a hydrogenated conjugated diene polymer having a hydrogenation rate of 80% or more using the compound represented by the above formula (1) (specific modifier) as a modifier at the end of polymerization (implementation) Examples 1 to 6) are compared with a hydrogenated conjugated diene polymer (Comparative Example 1) in which the compound represented by the above formula (1) was not used. It was found that various characteristics such as grip characteristics and low hysteresis loss characteristics are expressed in a well-balanced manner. In addition, the hydrogenated conjugated diene polymer of Comparative Example 2 in which the polymerization termination terminal was modified with a specific modifier but the hydrogenation rate was 70% was inferior to those of the Examples in breaking strength and abrasion resistance. .

Claims

A method for producing a hydrogenated conjugated diene polymer, which is a hydrogenated product of a conjugated diene polymer having a structural unit derived from butadiene,
A step of polymerizing a monomer containing butadiene in the presence of at least one of an alkali metal compound and an alkaline earth metal compound to obtain a conjugated diene polymer having an active end;
A step of reacting the conjugated diene polymer having an active terminal with a compound represented by the following formula (1);
And hydrogenating the hydrogenation rate of the structural unit derived from the butadiene of the conjugated diene polymer so as to be 80 to 99%.

(In Formula (1), X 1 is a silicon atom or a nitrogen atom, R 1 is a single bond or an alkanediyl group, R 2 is an alkanediyl group, and R 3 is a hydrocarbyl group. 1 is a hydrocarbyl group or a group represented by “—R 4 -A 2 ”, provided that when k = 0, A 1 is a group having a hydrocarbyloxysilyl group, and B 1 is X 1 In the case of a silicon atom, it has a hydrocarbyl group, a group represented by “—R 4 -A 2 ”, or at least one atom selected from the group consisting of nitrogen, phosphorus, oxygen and sulfur in the ring and is active A monovalent cyclic group having no hydrogen, and when X 1 is a nitrogen atom, a hydrocarbyl group, a group represented by “—R 4 -A 2 ”, a trihydrocarbylsilyl group, or nitrogen, phosphorus, Selected from the group consisting of oxygen and sulfur A monovalent cyclic group having no have and active hydrogen at least one atom in the ring .R 4 is a hydrocarbylene group, A 2 is the group consisting of nitrogen, oxygen, phosphorus, sulfur and silicon A monovalent functional group having at least one atom selected from the above, having no active hydrogen, and bonded to R 4 with nitrogen, oxygen, phosphorus, sulfur, or silicon, wherein R 3 , R 4 , A 2 may be the same or different from each other, j and k are integers, provided that when X 1 is a silicon atom, k is 1 or 2 and j + k = 2 And when X 1 is a nitrogen atom, j = 1 and k = 0.)
The compound represented by the formula (1) is at least one selected from the group consisting of a compound represented by the following formula (1-1) and a compound represented by the following formula (1-2). 2. A process for producing a hydrogenated conjugated diene polymer according to 1.

(In the formula (1-1), A 11 is a hydrocarbyl group, B 11 is a hydrocarbyl group or a group represented by “—R 4 -A 2 ”, and n is 1 or 2. R 2 , R 3 , R 4 and A 2 have the same meanings as in the above formula (1).
In Formula (1-2), R 11 is an alkanediyl group, A 12 is a group represented by “—R 4 —Si (R 5 ) m (OR 6 ) 3-m ”, and B 12 is , A hydrocarbyl group, a group represented by “—R 4 -A 2 ”, or a trihydrocarbylsilyl group. R 5 and R 6 are each independently a hydrocarbyl group, and m is an integer of 0-2. R 2 , R 4 and A 2 have the same meaning as in the above formula (1). )
A hydrogenated conjugated diene polymer that is a hydrogenated product of a conjugated diene polymer having a structural unit derived from butadiene,
It is a reaction product of a conjugated diene polymer having a structural unit derived from butadiene and having an alkali metal or an alkaline earth metal at the polymer terminal, and a compound represented by the following formula (1): In addition, a hydrogenated conjugated diene polymer, wherein a hydrogenation rate of a structural unit derived from the butadiene of the conjugated diene polymer is 80 to 99%.

(In Formula (1), X 1 is a silicon atom or a nitrogen atom, R 1 is a single bond or an alkanediyl group, R 2 is an alkanediyl group, and R 3 is a hydrocarbyl group. 1 is a hydrocarbyl group or a group represented by “—R 4 -A 2 ”, provided that when k = 0, A 1 is a group having a hydrocarbyloxysilyl group, and B 1 is X 1 In the case of a silicon atom, the ring has a hydrocarbyl group, a group represented by “—R 4 —A 2 ”, or at least one atom selected from the group consisting of nitrogen, phosphorus, oxygen and sulfur, and A monovalent cyclic group having no active hydrogen, and when X 1 is a nitrogen atom, a hydrocarbyl group, a group represented by “—R 4 -A 2 ”, a trihydrocarbylsilyl group, or nitrogen, phosphorus Selected from the group consisting of oxygen and sulfur At least have one atom in the ring that, and a monovalent cyclic group having no active hydrogen .R 4 is a hydrocarbylene group, A 2 is nitrogen, oxygen, phosphorus, sulfur and silicon A monovalent functional group having at least one atom selected from the group consisting of, having no active hydrogen, and bonded to R 4 with nitrogen, oxygen, phosphorus, sulfur or silicon, wherein R 3 , When a plurality of R 4 and A 2 are present, they may be the same or different from each other, j and k are integers, provided that when X 1 is a silicon atom, k is 1 or 2, and j + k = 2 and when X 1 is a nitrogen atom, j = 1 and k = 0.)
A polymer composition comprising the hydrogenated conjugated diene polymer obtained by the production method according to claim 1 or 2, or the hydrogenated conjugated diene polymer according to claim 3, silica, and a crosslinking agent. .
A crosslinked polymer obtained by crosslinking the polymer composition according to claim 4.
A tire using the crosslinked polymer according to claim 5 as at least a tread or sidewall material.