KR20210075015A - Method for producing branched conjugated diene polymer, branched conjugated diene polymer, method for producing rubber composition, and method for producing tire - Google Patents

Abstract

Provided is a method for producing a branched conjugated diene-based polymer having excellent fuel efficiency, abrasion resistance, wet skid resistance and breaking strength. The method for producing the branched conjugated diene-based polymer comprises: a polymerization step of obtaining a conjugated diene-based polymer having an active terminal by polymerizing or copolymerizing a conjugated diene compound or a conjugated diene compound and an aromatic vinyl compound by using an alkali metal compound or an alkaline earth metal compound as a polymerization initiator; and a branching step of introducing a branched structure by reacting a styrene derivative as a branching agent to the active end of the conjugated diene polymer.

Description

A method for producing a branched conjugated diene-based polymer, a method for producing a branched conjugated diene-based polymer, a method for producing a rubber composition, and a method for producing a tire TECHNICAL FIELD PRODUCING TIRE}

The present invention relates to a method for producing a branched conjugated diene-based polymer, a branched conjugated diene-based polymer, a method for producing a rubber composition, and a method for producing a tire.

BACKGROUND ART Conventionally, from the viewpoint of environmental load, there has been an increasing demand for fuel economy reduction in automobiles. In particular, with respect to automobile tires, improvement of low fuel efficiency is required for materials used for tread portions in direct contact with the ground.

In recent years, the development of a material having a low rolling resistance, that is, a low hysteresis loss property, has been demanded.

At the same time, there is a trend of tire weight reduction, and for that purpose, it is necessary to reduce the thickness of the tire tread, and at the same time, a material with high wear resistance is required for the tire tread.

On the other hand, from the viewpoint of safety, the material used for the tire tread portion is required to be excellent in wet skid resistance and to have practically sufficient breaking properties.

As a material satisfying various requirements as described above, a rubber material containing a rubbery polymer and a reinforcing filler such as carbon black or silica can be mentioned.

If the rubber material containing silica is used, the balance between low hysteresis loss property (index of low fuel efficiency) and wet skid resistance can be improved. In addition, by introducing a functional group having affinity or reactivity with silica into the molecular terminal portion of the rubber-like polymer with high mobility, the dispersibility of silica in the rubber material is improved, and furthermore, the rubber-like polymer is bonded to silica particles. By reducing the mobility of the molecular terminal portion of the polymer, it is possible to reduce the hysteresis loss.

On the other hand, as a method of improving abrasion resistance, the method of increasing the molecular weight of a rubber-like polymer is mentioned. However, when the molecular weight is increased, the processability at the time of kneading the rubbery polymer and the reinforcing filler tends to deteriorate.

In view of such circumstances, an attempt has been made to introduce a branched structure into the rubbery polymer in order to increase the molecular weight without impairing workability.

For example, conventionally, a resin composition of a modified conjugated diene polymer obtained by reacting an amino group-containing alkoxysilane with an active terminal of a conjugated diene polymer and silica has been proposed.

Further, there has been proposed a modified conjugated diene-based polymer in which a branched structure obtained by a coupling reaction between an active end of a polymer and a polyfunctional silane compound is introduced (for example, refer to Patent Documents 1 and 2).

International Publication No. 2007/114203 pamphlet International Publication No. 2016/133154 pamphlet

However, in the method of introducing a branched structure into a conjugated diene-based polymer in which the active end of the polymer and the polyfunctional silane compound are subjected to a coupling reaction, the degree of branching of the modified conjugated diene-based polymer obtained thereby is determined by the active end of the polymer possessed by the polyfunctional silane compound. It largely depends on the number of reactive groups with and does not become more than reactive groups. From the viewpoint of synthesis possibility, since there is a limit to the number of reactive groups that can be provided to one polyfunctional silane, there is a problem that the degree of branching of the obtained modified conjugated diene-based polymer is also limited.

Therefore, in the present invention, by introducing a branching point into the main chain, a conjugated diene-based polymer having a higher degree of branching can be produced than when a branched structure is introduced into the conjugated diene-based polymer using only a modifier or a coupling agent, and It is intended to provide a method for producing a branched conjugated diene-based polymer with a high degree of freedom in polymer design, in which the length of the main chain or side chain can be adjusted, thereby providing a branched conjugate excellent in low fuel consumption, abrasion resistance, wet skid resistance and breaking strength. An object of the present invention is to provide a method for producing a diene-based polymer.

As a result of intensive research and examination in order to solve the problems of the prior art described above, the present inventors reacted a conjugated diene-based polymer having an active terminal with a specific styrene derivative as a branching agent to introduce branching points into the main chain. The manufacturing method of a conjugated diene type polymer was discovered, and it came to complete this invention.

That is, the present invention is as follows.

〔One〕

A polymerization step of obtaining a conjugated diene polymer having an active terminal by polymerizing or copolymerizing a conjugated diene compound or a conjugated diene compound and an aromatic vinyl compound using an alkali metal compound or an alkaline earth metal compound as a polymerization initiator;

A branching process of introducing a branched structure by reacting a styrene derivative as a branching agent to the active end of the conjugated diene-based polymer

A method for producing a branched conjugated diene-based polymer having a.

〔2〕

The method for producing a branched conjugated diene-based polymer according to [1], further comprising a step of adding a conjugated diene compound and/or an aromatic vinyl compound to the reaction system during and/or after the branching step.

[3]

The method for producing a branched conjugated diene-based polymer according to the above [1] or [2], further comprising a reaction step of reacting a coupling agent or a polymerization terminator with the active terminal of the conjugated diene-based polymer obtained in the branching step.

〔4〕

The method for producing a branched conjugated diene-based polymer according to [3], wherein the coupling agent has a nitrogen atom-containing group.

[5]

The method for producing a branched conjugated diene-based polymer according to [3], wherein the polymerization terminator has a nitrogen atom-containing group.

[6]

The method for producing a branched conjugated diene-based polymer according to [3] or [5], wherein the polymerization terminator is an alkoxy compound having a nitrogen atom-containing group.

[7]

The method for producing a branched conjugated diene-based polymer according to [4], wherein the coupling agent is represented by the following formula (a).

(In formula (a), R ¹ to R ⁴ each independently represent an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and R ⁵ to R ⁶ are each independently, each independently having 1 to 20 carbon atoms represents an alkylene group.

m and n are integers of 1 to 3, and in formula (a), a plurality of R ¹ to R ⁶ , m, and n may be the same or different.

In the formula (a), X is represented by any of the following general formulas (b) to (e).)

(In formula (b), R ⁷ represents a hydrocarbon group having 1 to 20 carbon atoms, and the hydrocarbon group may have a partially branched structure or a cyclic structure. R ⁸ is a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms. and may have a partially branched structure or a cyclic structure in the case of a hydrocarbon group.)

(In formula (c), R ⁹ represents a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and in the case of a hydrocarbon group, it may have a partially branched structure or a cyclic structure.)

(In formula (d), R ¹⁰ represents a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and in the case of a hydrocarbon group, it may have a partially branched structure or a cyclic structure.)

(In formula (e), R ¹¹ to R ¹⁴ each independently represents an alkylene group having 1 to 20 carbon atoms. R ¹⁵ to R ¹⁸ are each independently an alkyl group having 1 to 20 carbon atoms or an alkyl group having 6 to 20 carbon atoms. an aryl group, l and o each independently represent an integer of 1 to 3, and R ¹⁵ to R ¹⁸ in the case of two or more are each independent.)

〔8〕

The method for producing a branched conjugated diene polymer according to any one of [1] to [7], wherein the styrene derivative is a compound represented by the following formulas (1) and/or (2).

(In formulas (1) and (2), R ¹ represents any selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, and an aryl group having 6 to 20 carbon atoms, and may have a branched structure in a part thereof. .

X ¹ , X ² , and X ³ are a single bond or an organic group containing any one selected from the group consisting of carbon, hydrogen, nitrogen, sulfur and oxygen.

Y ¹ , Y ² , and Y ³ represent any selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, and a halogen atom. Each is independent and may be the same or different.)

[9]

In the formula (1), R ¹ is a hydrogen atom, Y ¹ is any one selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, and a halogen atom. A method for producing a branched conjugated diene-based polymer.

[10]

In the formula (2), Y ² is any one selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, and a halogen atom. manufacturing method.

[11]

In the formula (1), R ¹ is a hydrogen atom and Y ¹ is an alkoxy group having 1 to 20 carbon atoms or a halogen atom, the method for producing a branched conjugated diene polymer according to the above [8].

[12]

In the formula (2), Y ² is an alkoxy group having 1 to 20 carbon atoms or a halogen atom, and Y ³ is an alkoxy group having 1 to 20 carbon atoms or a halogen atom, the branched conjugate according to [8] above. Method for producing a diene-based polymer.

[13]

In the formula (1), R ¹ is a hydrogen atom and Y ¹ is an alkoxy group having 1 to 20 carbon atoms, the method for producing a branched conjugated diene-based polymer according to [8].

[14]

In the formula (1), R ¹ is a hydrogen atom, X ¹ is a single bond, and Y ¹ is an alkoxy group having 1 to 20 carbon atoms, the method for producing a branched conjugated diene-based polymer according to [8].

[15]

In the formula (2), X ² is a single bond, Y ² is an alkoxy group having 1 to 20 carbon atoms or a halogen atom, X ³ is a single bond, Y ³ is an alkoxy group having 1 to 20 carbon atoms, or a halogen atom, the method for producing a branched conjugated diene-based polymer according to [8].

[16]

A conjugated diene-based polymer having an active end having a branched structure, and

A compound represented by the following formula (a)

A branched conjugated diene polymer that is the reaction product of

(In formula (a), R ¹ to R ⁴ each independently represent an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and R ⁵ to R ⁶ are each independently, each independently having 1 to 20 carbon atoms represents an alkylene group.

m and n are integers of 1 to 3, and in formula (a), a plurality of R ¹ to R ⁶ , m, and n may be the same or different.

In the formula (a), X is represented by any of the following general formulas (b) to (e).)

(In formula (b), R ⁷ represents a hydrocarbon group having 1 to 20 carbon atoms, and the hydrocarbon group may have a partially branched structure or a cyclic structure. R ⁸ is a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms. and may have a partially branched structure or a cyclic structure in the case of a hydrocarbon group.)

(In formula (c), R ⁹ represents a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and in the case of a hydrocarbon group, it may have a partially branched structure or a cyclic structure.)

(In formula (d), R ¹⁰ represents a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and in the case of a hydrocarbon group, it may have a partially branched structure or a cyclic structure.)

(In formula (e), R ¹¹ to R ¹⁴ each independently represents an alkylene group having 1 to 20 carbon atoms. R ¹⁵ to R ¹⁸ are each independently an alkyl group having 1 to 20 carbon atoms or an alkyl group having 6 to 20 carbon atoms. an aryl group, l and o each independently represent an integer of 1 to 3, and R ¹⁵ to R ¹⁸ in the case of two or more are each independent.)

[17]

The branched conjugated diene polymer according to [16], wherein ^{OR 1} and/or OR ³ of the compound represented by the formula (a) has a branched structure.

[18]

A rubber component comprising 10% by mass or more of the branched conjugated diene-based polymer according to [16] or [17];

The rubber composition which contains 5.0 mass parts or more and 150 mass parts or less of a filler with respect to 100 mass parts of said rubber components.

[19]

A step of obtaining a branched conjugated diene-based polymer by the production method according to any one of [1] to [15];

A step of obtaining a rubber component containing 10% by mass or more of the branched conjugated diene-based polymer;

The process of obtaining a rubber composition by containing 5.0 mass parts or more and 150 mass parts or less of a filler with respect to 100 mass parts of said rubber components

A method for producing a rubber composition having a.

[20]

A step of obtaining a rubber composition by the method for producing the rubber composition described in [19] above;

A step of molding the rubber composition to obtain a tire

A method of manufacturing a tire having

According to the present invention, by introducing a branching point into the main chain, a branched conjugated diene-based polymer having a higher degree of branching than when only a coupling agent or a modifier is used can be produced, and the length of the main chain or side chain can be adjusted. It is possible to provide a method for producing a branched conjugated diene-based polymer having a high degree of freedom, thereby providing a method for producing a branched conjugated diene-based polymer having excellent low fuel consumption, abrasion resistance, wet skid resistance and breaking strength.

EMBODIMENT OF THE INVENTION Hereinafter, the form for implementing this invention (henceforth "this embodiment" is called.) is demonstrated in detail.

In addition, the following this embodiment is an illustration for demonstrating this invention, and this invention is not limited to the following embodiment. The present invention can be implemented with appropriate modifications within the scope of the gist.

[Method for Producing Branched Conjugated Diene-Based Polymer]

The manufacturing method of the branched conjugated diene-type polymer of this embodiment,

A polymerization step of obtaining a conjugated diene polymer having an active terminal by polymerizing or copolymerizing a conjugated diene compound or a conjugated diene compound and an aromatic vinyl compound using an alkali metal compound or an alkaline earth metal compound as a polymerization initiator;

It has a branching step of introducing a branched structure by reacting a styrene derivative as a branching agent to the active end of the conjugated diene-based polymer.

The conjugated diene polymer constituting the branched conjugated diene polymer is a homopolymer of a single conjugated diene compound, a polymer of another type of conjugated diene compound, that is, a copolymer, a copolymer of a conjugated diene compound and an aromatic vinyl compound. okay

According to the production method of the branched conjugated diene-based polymer of the present embodiment, by introducing a branching point into the main chain, a conjugated diene-based polymer having a higher degree of branching than when a branched structure is introduced into the conjugated diene-based polymer using only a coupling agent. can be prepared, and the length of the main chain or side chain can be adjusted.

(Polymerization process)

In the polymerization step in the method for producing a branched conjugated diene-based polymer of the present embodiment, a conjugated diene compound or a conjugated diene compound and an aromatic vinyl compound are polymerized using an alkali metal compound or an alkaline earth metal compound as a polymerization initiator. Alternatively, by copolymerizing, a conjugated diene-based polymer having an active terminal is obtained.

In a polymerization process, it is preferable to superpose|polymerize by the growth reaction by a living anionic polymerization reaction, and by this, the conjugated diene polymer which has an active terminal can be obtained.

<Polymerization Initiator>

As the polymerization initiator, an alkali metal compound or an alkaline earth metal compound is used.

It is preferable to use an organolithium compound, and, as for a polymerization initiator, it is more preferable to use an organic monolithium compound.

Although it is not limited to the following as an organic monolithium compound, For example, the organic monolithium compound of a low molecular compound and the organic monolithium compound of the solubilized oligomer are mentioned.

In addition, the organic monolithium compound can be used, for example, in the bonding mode between the organic group and the lithium, a compound having a carbon-lithium bond, a compound having a nitrogen-lithium bond, and a compound having a tin-lithium bond.

It is preferable to determine the usage-amount of a polymerization initiator according to the molecular weight of the target conjugated diene type polymer.

The usage-amount of monomers, such as a conjugated diene compound with respect to the usage-amount of a polymerization initiator, is related with the polymerization degree of the target conjugated diene type polymer. That is, it tends to relate to a number average molecular weight and/or a weight average molecular weight.

Therefore, in order to increase the molecular weight of the conjugated diene-based polymer, the polymerization initiator may be adjusted in the direction of decreasing it, and in order to decrease the molecular weight, the amount of the polymerization initiator may be adjusted in the direction of increasing it.

The organic monolithium compound is preferably an alkyllithium compound having a substituted amino group or dialkylaminolithium from the viewpoint of being used as one method of introducing a nitrogen atom into the conjugated diene-based polymer.

In this case, a conjugated diene-based polymer having a nitrogen atom containing an amino group at the polymerization initiating terminal is obtained.

The substituted amino group is an amino group having no active hydrogen or having a structure in which active hydrogen is protected.

Examples of the alkyllithium compound having an amino group having no active hydrogen include, but are not limited to, 3-dimethylaminopropyllithium, 3-diethylaminopropyllithium, 4-(methylpropylamino)butyllithium and 4-(methylpropylamino)butyllithium. and hexamethyleneiminobutyllithium.

Although it is not limited to the following as an alkyllithium compound which has an amino group of the structure which protected active hydrogen, For example, 3-bistrimethylsilylaminopropyl lithium and 4-trimethylsilyl methylamino butyl lithium are mentioned.

Examples of dialkylaminolithium include, but are not limited to, lithium dimethylamide, lithium diethylamide, lithium dipropylamide, lithium dibutylamide, lithium di-n-hexylamide, lithium diheptylamide, lithium di Isopropylamide, lithium dioctylamide, lithium-di-2-ethylhexylamide, lithium didecylamide, lithium ethylpropylamide, lithium ethylbutylamide, lithium ethylbenzylamide, lithium methylphenethylamide, lithium hexamethyleneimide , lithium pyrrolidide, lithium piperidide, lithium heptamethyleneimide, lithium morpholide, 1-lithioazacyclooctane, 6-lithio-1,3,3-trimethyl-6-azabicyclo[3.2. 1]octane and 1-lithio-1,2,3,6-tetrahydropyridine.

The organic monolithium compound having these substituted amino groups is an oligomeric organic monolithium compound obtained by reacting a small amount of a polymerizable monomer, for example, a monomer such as 1,3-butadiene, isoprene, or styrene, and solubilizing it with normal hexane or cyclohexane. can also be used.

The organic monolithium compound is preferably an alkyllithium compound from the viewpoints of industrial availability and control of polymerization reaction. In this case, the conjugated diene polymer which has an alkyl group at the polymerization initiation terminal is obtained.

Examples of the alkyllithium compound include, but are not limited to, n-butyllithium, sec-butyllithium, tert-butyllithium, n-hexyllithium, benzyllithium, phenyllithium, and stilbenelithium.

As the alkyllithium compound, n-butyllithium and sec-butyllithium are preferable from the viewpoint of easy industrial availability and control of polymerization reaction.

These organic monolithium compounds may be used individually by 1 type, and may use 2 or more types together. Moreover, you may use together with another organometallic compound.

As said other organometallic compound, an alkaline-earth metal compound, another alkali metal compound, and another organometallic compound are mentioned, for example.

Although not limited to the following as an alkaline-earth metal compound, For example, an organomagnesium compound, an organocalcium compound, and an organostrontium compound are mentioned. Moreover, the compound of the alkoxide of an alkaline-earth metal, a sulfonate, a carbonate, and an amide is also mentioned.

Examples of the organomagnesium compound include dibutylmagnesium and ethylbutylmagnesium.

As another organometallic compound, an organoaluminum compound is mentioned, for example.

Polymerization process WHEREIN: Although it is not limited to the following as a polymerization reaction mode, For example, the polymerization reaction mode of a batch type (it is also called "batch type") and a continuous type is mentioned.

In continuous mode, one or two or more connected reactors may be used. The continuous type reactor is, for example, a tank type having a stirrer or a tubular type reactor. In the continuous mode, preferably, a monomer, an inert solvent and a polymerization initiator are continuously fed to the reactor, a polymer solution containing a polymer is obtained in the reactor, and the polymer solution is continuously discharged.

As the batch type reactor, for example, a tank type reactor having a stirrer is used. In the batch method, preferably a monomer, an inert solvent and a polymerization initiator are fed, and if necessary, the monomer is added continuously or intermittently during polymerization to obtain a polymer solution containing the polymer in the reactor, and after the polymerization is completed, the polymer The solution is drained.

In the method for producing a branched conjugated diene-based polymer of the present embodiment, in the polymerization step, in order to obtain a conjugated diene-based polymer having a high ratio of active ends, the polymer is continuously discharged and subjected to the following reaction in a short time Where possible, continuous is preferred. In the continuous type, the number of reactors is not particularly limited, and one or two or more connected reactors can be used. As for the reactor, it is preferable to sufficiently contact the monomer and the polymerization initiator in a solution, and a tank type having a stirrer, a tube type, or the like is used. Although the number of reactors can be selected suitably, from a viewpoint of space saving of a manufacturing facility, one is preferable, and from a viewpoint of productivity improvement, two or more are preferable. When using two or more reactors, it is more preferable to add the branching agent mentioned later after the second stage.

The polymerization step of the conjugated diene-based polymer is preferably performed in an inert solvent.

Examples of the inert solvent include hydrocarbon solvents such as saturated hydrocarbons and aromatic hydrocarbons. Examples of the hydrocarbon-based solvent include, but are not limited to, aliphatic hydrocarbons such as butane, pentane, hexane and heptane; alicyclic hydrocarbons such as cyclopentane, cyclohexane, methylcyclopentane and methylcyclohexane; and hydrocarbons including aromatic hydrocarbons such as benzene, toluene, and xylene, and mixtures thereof.

By treating impurities such as allenes and acetylenes with an organometallic compound before being subjected to polymerization, a conjugated diene polymer having a high concentration of active ends tends to be obtained, and a modified conjugated diene polymer having a high modification rate tends to be obtained It is preferable because there is

In the polymerization step, a polar compound may be added. Thereby, an aromatic vinyl compound can be copolymerized at random with a conjugated diene compound. Moreover, there exists a tendency for a polar compound to be usable also as a vinylating agent for controlling the microstructure of a conjugated diene part. Moreover, there exists a tendency which is effective also in acceleration|stimulation of a polymerization reaction, etc.

Although it is not limited to the following as a polar compound, For example, tetrahydrofuran, diethyl ether, dioxane, ethylene glycol dimethyl ether, ethylene glycol dibutyl ether, diethylene glycol dimethyl ether, diethylene glycol dibutyl ether, dimer ethers such as oxybenzene and 2,2-bis(2-oxolanyl)propane; tertiary amine compounds such as tetramethylethylenediamine, dipiperidinoethane, trimethylamine, triethylamine, pyridine, and quinuclidine; alkali metal alkoxide compounds such as potassium-tert-amylate, potassium-tert-butyrate, sodium-tert-butyrate, and sodium amylate; Phosphine compounds, such as triphenylphosphine, etc. can be used.

These polar compounds may be used individually by 1 type, and may use 2 or more types together.

The usage-amount of a polar compound is not specifically limited, Although it can select according to the objective etc., It is preferable that they are 0.01 mol or more and 100 mol or less with respect to 1 mol of polymerization initiator.

Such a polar compound (vinylating agent) can be used in an appropriate amount according to the desired amount of vinyl bonds as a modifier for the microstructure of the conjugated diene moiety of the conjugated diene polymer.

Most of the polar compounds have an effective randomizing effect in the copolymerization of the conjugated diene compound and the aromatic vinyl compound at the same time, and tend to be usable as an aromatic vinyl compound distribution regulator and also as a styrene block amount regulator.

As a method of randomizing the conjugated diene compound and the aromatic vinyl compound, for example, as described in Japanese Unexamined Patent Application Publication No. 59-140211, a copolymerization reaction is started with the whole amount of styrene and a part of 1,3-butadiene. A method in which the remaining 1,3-butadiene is intermittently added during the copolymerization reaction may be used.

It is preferable that it is the temperature at which living anionic polymerization advances, and, as for the polymerization temperature in a polymerization process, it is more preferable that they are 0 degreeC or more and 120 degrees C or less from a viewpoint of productivity.

By being in such a range, there exists a tendency that the reaction amount of a branching agent and a coupling agent with respect to the active terminal after completion|finish of polymerization can fully be ensured. More preferably, it is 50 degreeC or more and 100 degrees C or less.

(branching process)

In the method for producing a branched conjugated diene-based polymer of the present embodiment, a branching step of reacting a styrene derivative as a branching agent to the active terminal of the conjugated diene-based polymer obtained in the polymerization step is performed.

While the branching agent maintains polymerization activity and polymerizes with the monomer, the active end of the other polymer chain reacts with the functional group of the branching agent, thereby forming a branched structure in the polymer. It is also possible to form a further branched structure by polymerizing and reacting the branched conjugated diene-based polymer introduced with a branched structure with a monomer and a branching agent, and reacting with a modifier having a functional group to obtain a modified conjugated diene-based polymer, or a couple It is also possible to further extend a polymer chain by ring reaction. As described above, the target branched conjugated diene polymer is obtained by using a styrene derivative in which a functional group reacts with the active terminal of the polymer as a branching agent while continuing the polymerization reaction as an aromatic vinyl compound.

<Branching agent>

The styrene derivative as a branching agent used in the branching process needs to be a main skeleton with only one active end remaining at the branching site after the branching reaction from the viewpoint of continuity of polymerization and prevention of gelation. It is necessary for the styrene derivative moiety formed after the reaction to have sufficient reactivity to react with other polymerization active terminals.

More specifically, the styrene derivative is preferably a compound having a vinyl group on the benzene ring and a functional group that quantitatively reacts with the polymerization active terminal of the living anionic polymerization. A branched structure is formed in the polymer by a one-to-one reaction between the functional group of the styrene derivative and the polymerization active terminal, and the vinyl group polymerization-reacts with other monomers in the reactor while the functional group is detached to form a single bond. Functional groups other than the vinyl group of the styrene derivative are groups that are removed by a nucleophilic substitution reaction with the polymerization active terminal of the living anionic polymerization, for example, an alkoxy group, a halogen, an ester group, a formyl group, a ketone group, an amide group. , an acid chloride group, an acid anhydride group, and an epoxy group.

By having such a structure, a styrene derivative is introduced into the main chain while the styrene derivative maintains its polymerization activity as styrene, and the polymer chain is further extended by polymerization of another monomer at the terminal where the activity is maintained. Furthermore, the active terminal of another polymer chain reacts with the functional group of the introduced styrene derivative, and a branched structure arises by forming a bond. As this reaction occurs repeatedly, branching of the polymer chain increases, the polymer structure becomes more complex, and the molecular weight becomes larger.

From the viewpoint of continuity of polymerization and controllability of the polymer structure, it is also necessary that the functional group detached after the styrene derivative moiety reacts with the active end of another polymer chain has less inhibitory effect on polymerization. Here, "there is little inhibitory effect on polymerization" means that there are few side reactions of anionic polymerization, such as chain transfer reaction, inactivation during polymerization, and decrease in activity due to an increase in the degree of association of the polymer.

The functional group of the styrene derivative needs not to excessively improve polymerization activity, and also needs to not deactivate polymerization activity. When polymerizing a polymer by living anionic polymerization, it is important that it does not have a hydrogen atom as a functional group that does not inactivate the active end, and that it is a hard base as stated in the definition based on Pearson's HASB law, and more specifically, an alkoxy group or A halogen group is mentioned. Among these, the structure of the styrene derivative as a branching agent used in the production method of the present embodiment can be selected from the viewpoint that the removed functional group does not inhibit polymerization in addition to reactivity with the active terminal.

More specifically, the use of a branching agent represented by the following formula (1) having a styrene skeleton as the main skeleton or formula (2) having a diphenylethylene skeleton as the main skeleton is effective in inhibiting chain transfer reaction and reducing the active end. It is preferable from a viewpoint of deactivation suppression and gelation prevention.

(In formulas (1) and (2), R ¹ represents any selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, and an aryl group having 6 to 20 carbon atoms, and may have a branched structure in a part thereof. .

X ¹ , X ² , and X ³ are a single bond or an organic group containing any one selected from the group consisting of carbon, hydrogen, nitrogen, sulfur and oxygen.

Y ¹ , Y ² , and Y ³ represent any selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, and a halogen atom. Each is independent and may be the same or different.)

In the styrene derivative used in the branching step, which is a branching agent, from the viewpoint of improving the degree of branching of polymerization, in the formula (1), R ¹ is a hydrogen atom, Y ¹ is an alkyl group having 1 to 20 carbon atoms, and 1 carbon number. Any one selected from the group consisting of an alkoxy group of 20 to 20 and a halogen atom is preferable.

In the present embodiment, the styrene derivative as a branching agent used in the branching step is, from the viewpoint of improving the branching degree, in the formula (2), Y ² is an alkyl group having 1 to 20 carbon atoms, 1 to carbon atoms. Any one selected from the group consisting of an alkoxy group of 20 and a halogen atom is preferable.

In addition, in the present embodiment, in the styrene derivative used in the branching step, which is a branching agent, in the above formula (1), R ¹ is a hydrogen atom, and Y ¹ is from the viewpoint of continuity of polymerization and improvement of branching degree. , an alkoxy group having 1 to 20 carbon atoms, or a halogen atom is more preferable.

Further, in terms of In,, branching agent is a styrene derivative is used in a branching process, improved continuity and minutes of the polymerization leading to the present embodiment, the formula (2):, Y ² is an alkoxy group, or a halogen atom and Y ³ is more preferably an alkoxy group having 1 to 20 carbon atoms or a halogen atom.

In addition, in the present embodiment, in the styrene derivative used in the branching step, which is a branching agent, from the viewpoint of continuity of polymerization, improvement of branching degree, and improvement of denaturation rate, R ¹ is a hydrogen atom, , Y ¹ is more preferably an alkoxy group having 1 to 20 carbon atoms.

In addition, in the present embodiment, the styrene derivative used in the branching step, which is a branching agent, is from the viewpoint of improving the continuity of polymerization and the degree of branching, and further improving the rate of denaturation, in the formula (1), R ¹ is More preferably, it is a hydrogen atom, X ¹ is a single bond, and Y ¹ is an alkoxy group having 1 to 20 carbon atoms.

In addition, in the present embodiment, the styrene derivative used in the branching step, which is a branching agent, is from the viewpoint of improving the continuity of polymerization and the degree of branching, and further improving the rate of denaturation, in the above formula (2), X ² is It is more preferable that it is a single bond, Y ² is an alkoxy group having 1 to 20 carbon atoms or a halogen atom, X ³ is a single bond, and Y ³ is an alkoxy group having 1 to 20 carbon atoms or a halogen atom.

Although not limited to the following as a branching agent represented by said Formula (1), For example, trimethoxy (4-vinylphenyl) silane, triethoxy (4-vinylphenyl) silane, tripropoxy (4- Vinylphenyl)silane, tributoxy(4-vinylphenyl)silane, triisopropoxy(4-vinylphenyl)silane, trimethoxy(3-vinylphenyl)silane, triethoxy(3-vinylphenyl)silane, Tripropoxy (3-vinylphenyl) silane, tributoxy (3-vinylphenyl) silane, triisopropoxy (3-vinylphenyl) silane, trimethoxy (2-vinylphenyl) silane, triethoxy (2 -Vinylphenyl)silane, tripropoxy(2-vinylphenyl)silane, tributoxy(2-vinylphenyl)silane, triisopropoxy(2-vinylphenyl)silane, dimethoxymethyl(4-vinylphenyl)silane , diethoxymethyl (4-vinylphenyl) silane, dipropoxymethyl (4-vinylphenyl) silane, dibutoxymethyl (4-vinylphenyl) silane, diisopropoxymethyl (4-vinylphenyl) silane, dimethoxy Methyl (3-vinylphenyl) silane, diethoxymethyl (3-vinylphenyl) silane, dipropoxymethyl (3-vinylphenyl) silane, dibutoxymethyl (3-vinylphenyl) silane, diisopropoxymethyl (3) -Vinylphenyl)silane, dimethoxymethyl(2-vinylphenyl)silane, diethoxymethyl(2-vinylphenyl)silane, dipropoxymethyl(2-vinylphenyl)silane, dibutoxymethyl(2-vinylphenyl)silane , diisopropoxymethyl(2-vinylphenyl)silane, dimethylmethoxy(4-vinylphenyl)silane, dimethylethoxy(4-vinylphenyl)silane, dimethylpropoxy(4-vinylphenyl)silane, dimethylbutoxy (4-vinylphenyl)silane, dimethylisopropoxy(4-vinylphenyl)silane, dimethylmethoxy(3-vinylphenyl)silane, dimethylethoxy(3-vinylphenyl)silane, dimethylpropoxy(3-vinylphenyl)silane )silane, dimethylbutoxy(3-vinylphenyl)silane, dimethylisopropoxy(3-vinylphenyl)silane, dimethylmethoxy(2-vinylphenyl)silane, dimethylethoxy(2-vinylphenyl)silane, dimethylpropane Foxy(2-vinylphenyl)silane, dimethylbutoxy(2-vinylphenyl)silane, dimethylisopropoxy(2-vinylphenyl)silane, trimethoxy(4-isopropenylphenyl)silane, triethoxy(4 -Isopropenylphenyl)silane, tripropoxy(4-isopropenylphenyl)silane, tributoxy(4-isopropenylphenyl)silane, triisopropoxy(4-isopropenylphenyl)silane, trime Toxy (3-isopropene Nylphenyl) silane, triethoxy (3-isopropenylphenyl) silane, tripropoxy (3-isopropenylphenyl) silane, tributoxy (3-isopropenylphenyl) silane, triisopropoxy (3 -Isopropenylphenyl)silane, trimethoxy(2-isopropenylphenyl)silane, triethoxy(2-isopropenylphenyl)silane, tripropoxy(2-isopropenylphenyl)silane, tributoxy (2-isopropenylphenyl)silane, triisopropoxy (2-isopropenylphenyl)silane, dimethoxymethyl (4-isopropenylphenyl)silane, diethoxymethyl (4-isopropenylphenyl)silane, Dipropoxymethyl (4-isopropenylphenyl) silane, dibutoxymethyl (4-isopropenylphenyl) silane, diisopropoxymethyl (4-isopropenylphenyl) silane, dimethoxymethyl (3-isopro Phenylphenyl)silane, diethoxymethyl (3-isopropenylphenyl)silane, dipropoxymethyl (3-isopropenylphenyl)silane, dibutoxymethyl (3-isopropenylphenyl)silane, diisopropoxymethyl (3-isopropenylphenyl)silane, dimethoxymethyl (2-isopropenylphenyl)silane, diethoxymethyl (2-isopropenylphenyl)silane, dipropoxymethyl (2-isopropenylphenyl)silane, Dibutoxymethyl (2-isopropenylphenyl) silane, diisopropoxymethyl (2-isopropenylphenyl) silane, dimethylmethoxy (4-isopropenylphenyl) silane, dimethylethoxy (4-isopropenyl) Phenyl)silane, dimethylpropoxy(4-isopropenylphenyl)silane, dimethylbutoxy(4-isopropenylphenyl)silane, dimethylisopropoxy(4-isopropenylphenyl)silane, dimethylmethoxy(3- Isopropenylphenyl)silane, dimethylethoxy(3-isopropenylphenyl)silane, dimethylpropoxy(3-isopropenylphenyl)silane, dimethylbutoxy(3-isopropenylphenyl)silane, dimethylisopropoxy (3-isopropenylphenyl)silane, dimethylmethoxy(2-isopropenylphenyl)silane, dimethylethoxy(2-isopropenylphenyl)silane, dimethylpropoxy(2-isopropenylphenyl)silane, dimethyl Butoxy (2-isopropenylphenyl) silane, dimethyl isopropoxy (2-isopropenylphenyl) silane, trichloro (4-vinylphenyl) silane, trichloro (3-vinylphenyl) silane, trichloro (2) -Vinylphenyl)silane, tribromo(4-vinylphenyl)silane, tribromo(3-vinylphenyl)silane, tribromo(2-vinylphenyl)silane, dichloromethyl (4- Vinylphenyl) silane, dichloromethyl (3-vinylphenyl) silane, dichloromethyl (2-vinylphenyl) silane, dibromomethyl (4-vinylphenyl) silane, dibromomethyl (3-vinylphenyl) silane, dibromomethyl (3-vinylphenyl) silane Bromomethyl(2-vinylphenyl)silane, dimethylchloro(4-vinylphenyl)silane, dimethylchloro(3-vinylphenyl)silane, dimethylchloro(2-vinylphenyl)silane, dimethylbromo(4-vinylphenyl) Silane, dimethylbromo(3-vinylphenyl)silane, dimethylbromo(2-vinylphenyl)silane, trimethoxy(4-vinylbenzyl)silane, triethoxy(4-vinylbenzyl)silane, tripropoxy( 4-vinylbenzyl)silane.

Among these, trimethoxy (4-vinylphenyl) silane, triethoxy (4-vinylphenyl) silane, tripropoxy (4-vinylphenyl) silane, tributoxy (4-vinylphenyl) silane and triisopro Foxy(4-vinylphenyl)silane, trimethoxy(3-vinylphenyl)silane, triethoxy(3-vinylphenyl)silane, tripropoxy(3-vinylphenyl)silane, tributoxy(3-vinylphenyl) ) silane, triisopropoxy (3-vinylphenyl) silane, trichloro (4-vinylphenyl) silane is preferable, trimethoxy (4-vinylphenyl) silane, triethoxy (4-vinylphenyl) silane, Tripropoxy (4-vinylphenyl) silane, tributoxy (4-vinylphenyl) silane, triisopropoxy (4-vinylphenyl) silane, trimethoxy (4-vinylbenzyl) silane, triethoxy (4- Vinylbenzyl)silane is more preferable, and trimethoxy(4-vinylphenyl)silane and triethoxy(4-vinylphenyl)silane are still more preferable.

Although not limited to the following as a branching agent represented by said Formula (2), For example, 1-bis(4-trimethoxysilylphenyl)ethylene, 1, 1-bis(4-triethoxysilylphenyl) Ethylene, 1,1-bis(4-tripropoxysilylphenyl)ethylene, 1,1-bis(4-tripentoxysilylphenyl)ethylene, 1,1-bis(4-triisopropoxysilylphenyl)ethylene , 1,1-bis(3-trimethoxysilylphenyl)ethylene, 1,1-bis(3-triethoxysilylphenyl)ethylene, 1,1-bis(3-tripropoxysilylphenyl)ethylene, 1 ,1-bis(3-tripentoxysilylphenyl)ethylene, 1,1-bis(3-triisopropoxysilylphenyl)ethylene, 1,1-bis(2-trimethoxysilylphenyl)ethylene, 1, 1-bis(2-triethoxysilylphenyl)ethylene, 1,1-bis(3-tripropoxysilylphenyl)ethylene, 1,1-bis(2-tripentoxysilylphenyl)ethylene, 1,1- bis(2-triisopropoxysilylphenyl)ethylene, 1,1-bis(4-(dimethylmethoxysilyl)phenyl)ethylene, 1,1-bis(4-(diethylmethoxysilyl)phenyl)ethylene; 1,1-bis(4-(dipropylmethoxysilyl)phenyl)ethylene, 1,1-bis(4-(dimethylethoxysilyl)phenyl)ethylene, 1,1-bis(4-(diethylethoxy) Silyl)phenyl)ethylene, 1,1-bis(4-(dipropylethoxysilyl)phenyl)ethylene, 1,1-bis(4-trimethoxysilylbenzyl)ethylene, 1,1-bis(4-tri and ethoxysilylbenzyl)ethylene, 1,1-bis(4-tripropoxysilylbenzyl)ethylene, and 1,1-bis(4-tripentoxysilylbenzyl)ethylene.

Among these, 1,1-bis(4-trimethoxysilylphenyl)ethylene, 1,1-bis(4-triethoxysilylphenyl)ethylene, 1,1-bis(4-tripropoxysilylphenyl) Ethylene, 1,1-bis(4-tripentoxysilylphenyl)ethylene and 1,1-bis(4-triisopropoxysilylphenyl)ethylene are preferable, and 1,1-bis(4-trimethoxysilyl) Phenyl)ethylene is more preferred.

By using the branching agent represented by the formulas (1) and (2), the branching index is improved, and the effect of improving abrasion resistance and workability is obtained.

The timing for adding the branching agent is not particularly limited and can be selected depending on the purpose, but from the viewpoint of improving the absolute molecular weight of the branched conjugated diene-based polymer and improving the coupling rate, after the polymerization initiator is added, the raw material conversion ratio is 20% or more The timing is preferable, more preferably 40% or more, still more preferably 50% or more, still more preferably 65% or more, and even more preferably 75% or more.

Further, during and/or after the branching step, a monomer as a desired raw material may be further added, and the polymerization step may be continued after the branching step, and the contents described above may be repeated.

In addition, it is assumed that after a branching process is after adding a branching agent.

Although the monomer to be added is not specifically limited, It is preferable that it is a conjugated diene compound and/or an aromatic vinyl compound, Especially when adding a monomer in the case of a branching process, steric hindrance relief at the branching point of a conjugated diene type polymer. From the viewpoint of improving the rate of modification by , the total amount of the conjugated diene-based monomer used in the polymerization step, for example, is preferably 5% or more of the total amount of butadiene, more preferably 10% or more, still more preferably 15% or more, 20 % or more is still more preferable, and it is particularly more preferable that it is 25% or more. In this case, in particular, in the branching process using a continuous polymerization process, adding the monomer in an amount of 5% or more of the total amount of the conjugated diene-based monomer used in the polymerization process, for example, the total amount of butadiene is from the viewpoint of improving the denaturation rate. preferred in

Depending on the timing of adding the branching agent and the amount of the monomer to be added, the length of the main chain or side chain can be adjusted, so the degree of freedom in polymer design is high.

The branched structure of the branched conjugated diene polymer obtained in the branching step in the method for producing the branched conjugated diene polymer of the present embodiment is preferably 3 branches or more and 24 branches or less, more preferably 4 branches or more. They are 20 or less branches, and more preferably 5 or more and 18 or less branches.

By having 24 branches or less, it tends to be easy to react with a modifier having a functional group to obtain a modified conjugated diene polymer, or to further extend the polymer chain by a coupling reaction. It tends to be excellent in abrasion resistance.

The addition amount of the branching agent is not particularly limited, and the addition amount can be selected depending on the purpose, etc., but from the viewpoint of improving the terminal stop reaction rate of the conjugated diene-based polymer, improving the coupling rate, and continuity of polymerization after branching, the amount of active polymerization initiator , the molar ratio of the branching agent is 1/2 or less and preferably 1/100 or more, more preferably 1/3 or less and 1/50 or more, and 1/4 or less and 1/30 or more It is still more preferable, and it is still more preferably 1/6 or less and 1/25 or more, and even more preferably 1/8 or less and 1/12 or more.

In addition, as described above, during and/or after the branching step, a monomer may be further added, and the polymerization step may be continued after branching, and a branching agent is added again after the additional monomer is added, and the monomer is added again. may be repeated.

By adding the monomer, effects such as improvement of continuity of polymerization and improvement of coupling rate and denaturation rate are obtained by relaxation of steric hindrance around the branch point. Thereby, a branched structure can be formed at a desired position while increasing the molecular weight of the polymer.

The monomer to be added may be an aromatic vinyl such as styrene, a conjugated diene compound such as butadiene, or a mixture thereof, and may be the same as or different from the type and ratio of the monomer to be initially polymerized. Diene compounds are preferred. It is preferable to add an aromatic vinyl compound from a viewpoint of improving the heat resistance of a polymer.

The branched conjugated diene-based polymer obtained in the branching step in the production method of the present embodiment preferably has a Mooney viscosity measured at 110°C of 10 or more and 150 or less, more preferably 15 or more and 140 or less, and further Preferably it is 20 or more and 130 or less. More preferably, it is 30 or more and 100 or less.

If the Mooney viscosity is within the above range, the branched conjugated diene polymer obtained by the production method of the present embodiment tends to be excellent in workability and abrasion resistance.

The weight average molecular weight of the branched conjugated diene-based polymer obtained in the branching step in the production method of the present embodiment is preferably 10000 or more and 1500000 or less, more preferably 100000 or more and 1000000 or less, and more preferably 200000 or more and 900000 or less. desirable.

If the weight average molecular weight is within the above range, the branched conjugated diene-based polymer obtained by the production method of the present embodiment tends to be excellent in workability, abrasion resistance, and balance of these properties.

In the case of producing a branched conjugated diene-based polymer, in order for the weight average molecular weight to reach 100000 or more and 1000000 or less, the addition amount of the branching agent to the polymerization initiator in a molar ratio is 1/3 or less and 1/5 or more. By controlling, it is necessary to make the number of functional groups of the coupling agent more than bifunctional while forming branches and preventing the polymerization initiator from being completely consumed before the coupling step. In order for the weight average molecular weight range to reach 200000 or more and 900000 or less, the number of functional groups in the coupling agent is trifunctional while controlling the addition amount of the branching agent in a molar ratio of 1/3 or less to the polymerization initiator and in the range of 1/50 or more. It is necessary to do more than

In the case of producing the modified branched conjugated diene-based polymer, in order to reach a weight average molecular weight of 100000 or more and 1000000 or less, the addition amount of the branching agent to the polymerization initiator in a molar ratio is 1/3 or less and 1/50 or more By controlling in the range, while forming a branch and preventing the polymerization initiator from being consumed before the coupling process, it is necessary to make the number of functional groups of the coupling agent bifunctional or more, and the range of the weight average molecular weight reaches 200000 or more and 900000 or less In order to do this, it is necessary to make the number of functional groups of the coupling agent trifunctional or more, while controlling the addition amount of the branching agent in a molar ratio of 1/3 or less to the polymerization initiator in the range of 1/50 or more.

The branched conjugated diene polymer obtained by the production method of the present embodiment may be a polymer of a conjugated diene monomer and a branching agent, or may be a copolymer of a conjugated diene monomer, a branching agent, and other monomers.

For example, when the conjugated diene monomer is butadiene or isoprene, and this and a branching agent containing an aromatic vinyl moiety are polymerized, the polymerized chain is so-called polybutadiene or polyisoprene, the branched moiety containing an aromatic vinyl-derived structure. become a polymer. By having such a structure, the improvement of the linearity per one polymer chain and the improvement of the crosslinking density after vulcanization are possible, thereby exhibiting the effect of the improvement of the abrasion resistance of a polymer. Therefore, it is suitable for uses, such as a tire, resin modification, the interior and exterior of an automobile, vibration-proof rubber, and shoes.

When the conjugated diene-based polymer is provided for use as a tread of a tire, a copolymer of a conjugated diene monomer, an aromatic vinyl monomer, and a branching agent is suitable, and the amount of bonded conjugated diene in the copolymer for this use is 40% by mass or more and 100% by mass. It is preferable that they are below, and it is more preferable that they are 55 mass % or more and 80 mass % or less.

In addition, the amount of bonded aromatic vinyl in the branched conjugated diene-based polymer obtained by the production method of the present embodiment is not particularly limited, but is preferably 0% by mass or more and 60% by mass or less, more preferably 20% by mass or more and 45% by mass or less desirable.

When the amount of bonded conjugated diene and the amount of bonded aromatic vinyl are within the above ranges, the balance between low hysteresis loss and wet skid resistance, abrasion resistance, and fracture characteristics in the case of a vulcanized product tend to be more excellent.

Here, the amount of bonded aromatic vinyl can be measured by ultraviolet absorption of the phenyl group, and the amount of bonded conjugated diene can also be determined here. Specifically, it can measure according to the method described in the Example mentioned later.

In the branched conjugated diene-based polymer obtained by the production method of the present embodiment, the amount of vinyl bonds in the conjugated diene bonding unit is not particularly limited, but is preferably 10 mol% or more and 75 mol% or less, and 20 mol% or more and 65 mol% or more. It is more preferable that it is mol% or less.

When the amount of vinyl bonds is within the above range, the balance between low hysteresis loss and wet skid resistance, abrasion resistance, and breaking strength in the case of a vulcanized product tends to be more excellent.

Here, when the branched conjugated diene-based polymer is a copolymer of butadiene and styrene, the amount of vinyl bonds in the butadiene bonding unit (1,2) according to the Hampton method (RR Hampton, Analytical Chemistry, 21, 923 (1949)) -binding amount) can be obtained. Specifically, it can measure by the method described in the Example mentioned later.

Regarding the microstructure of the branched conjugated diene polymer, the amount of each bond in the branched conjugated diene polymer obtained by the production method of the present embodiment is within the above-mentioned numerical range, and the glass transition temperature of the branched conjugated diene polymer When is in the range of -80°C or more and -15°C or less, there is a tendency that a vulcanized product having a much better balance between low hysteresis loss and wet skid resistance can be obtained.

As for the glass transition temperature, according to ISO 22768: 2006, the DSC curve is recorded while the temperature is raised in a predetermined temperature range, and the peak top of the DSC differential curve is called the glass transition temperature.

When the branched conjugated diene-based polymer obtained by the production method of the present embodiment is a conjugated diene-aromatic vinyl copolymer, the branched conjugated diene-based polymer has a small number of blocks in which 30 or more aromatic vinyl units are chained, or Or it is preferred that there is none. More specifically, when the branched conjugated diene-based polymer obtained by the production method of the present embodiment is a butadiene-styrene copolymer, the method of Kolthoff (IM KOLTHOFF, et al., J. Polym. Sci. 1, 429 (1946) In the known method of decomposing the polymer by the method described in )) and analyzing the amount of polystyrene insoluble in methanol, the block in which 30 or more aromatic vinyl units are chained is based on the total amount of the branched conjugated diene-based polymer, Preferably it is 5.0 mass % or less, More preferably, it is 3.0 mass % or less.

When the branched conjugated diene-based polymer obtained by the production method of the present embodiment is a conjugated diene-aromatic vinyl copolymer, from the viewpoint of improving fuel economy performance, it is preferable that the ratio in which the aromatic vinyl unit exists alone is higher.

Specifically, when the branched conjugated diene-based polymer obtained by the production method of the present embodiment is a butadiene-styrene copolymer, it is a method by ozone decomposition known as the method by Tanaka et al. (Polymer, 22, 1721 (1981)). , When the branched conjugated diene polymer is decomposed and the styrene chain distribution is analyzed by GPC, the amount of isolated styrene is 40 mass% or more with respect to the total amount of combined styrene, and the chain styrene structure in which the styrene chain is 8 or more It is preferable that it is 5.0 mass % or less.

In this case, the obtained vulcanized rubber tends to have excellent performance with particularly low hysteresis loss.

(reaction process)

In the method for producing the branched conjugated diene-based polymer of the present embodiment, a coupling agent, for example, a trifunctional or higher reactive compound is used with respect to the active end of the conjugated diene-based polymer obtained through the polymerization step and branching step described above. It is preferable to carry out the step of performing the coupling or the step of reacting the active end of the conjugated diene-based polymer using a polymerization terminator, for example, a reactive compound having a bifunctional or lower function.

Hereinafter, the process of reacting a coupling agent (coupling process) or the process of making polymerization stop reacting (polymerization stop process) are all called a reaction process.

In the reaction step, one end of the active terminal of the conjugated diene-based polymer is reacted with a coupling agent or a polymerization terminator.

<Coupling process>

In the manufacturing method of the conjugated diene type polymer of this embodiment, it is preferable to have the coupling process of coupling the conjugated diene type polymer obtained through the polymerization and branching process mentioned above with a coupling agent. By a coupling process, a molecular chain can be lengthened efficiently and a branch can also be introduce|transduced into a polymer by employ|adopting a trifunctional or more than trifunctional coupling agent. The function of forming a branch is common to the process using a branching agent, but by performing in the coupling process, a well-known coupling agent can be used to form a branch while introducing desired elements, such as nitrogen, sulfur, and silicon. preferred in

As the coupling step, for example, a coupling step performed using a trifunctional or higher reactive compound with respect to the active terminal of the conjugated diene polymer, or a coupling agent having a nitrogen atom-containing group (hereinafter referred to as “coupling agent” together) The coupling process performed using the coupling process performed using the following formula (a) is preferable, and the coupling process performed using the coupling agent represented by a following formula (a) is more preferable.

In the coupling step, for example, with respect to one end of the active terminal of the conjugated diene-based polymer, a reactive compound having a trifunctional or higher function, a coupling agent having a nitrogen atom-containing group, or a coupling agent represented by the following formula (a) is used for a coupling reaction. Thus, a branched conjugated diene-based polymer can be obtained.

[More than trifunctional reactive compound]

In the method for producing the branched conjugated diene-based polymer of the present embodiment, the trifunctional or higher reactive compound used in the coupling step is preferably a trifunctional or higher reactive compound having a silicon atom.

Although not limited to the following as a trifunctional or more than trifunctional reactive compound which has a silicon atom, For example, a halogenated silane compound, an epoxidized silane compound, a vinylated silane compound, an alkoxysilane compound, etc. are mentioned.

Although not limited to the following as a halogenated silane compound which is a coupling agent, For example, methyltrichlorosilane, tetrachlorosilane, tris(trimethylsiloxy)chlorosilane, tris(dimethylamino)chlorosilane, hexachlorodisilane, bis (trichlorosilyl)methane, 1,2-bis(trichlorosilyl)ethane, 1,2-bis(methyldichlorosilyl)ethane, 1,4-bis(trichlorosilyl)butane, 1,4-bis(methyl dichlorosilyl) butane and the like.

Although not limited to the following as an epoxidation silane compound which is a coupling agent, For example, 3-glycidoxy propyl trimethoxysilane, 3-glycidoxy propyl triethoxy silane, 3-glycidoxy propyl methyl diethoxy silane , epoxy-modified silicone, and the like.

Although not limited to the following as an alkoxysilane compound which is a coupling agent, For example, tetramethoxysilane, tetraethoxysilane, triphenoxymethylsilane, 1,2-bis(triethoxysilyl)ethane, methoxy substitution Polyorganosiloxane etc. are mentioned.

[Coupling agent having a nitrogen atom-containing group]

The coupling agent having a nitrogen atom-containing group is not limited to the following, but for example, an isocyanate compound, an isothiocyanate compound, an isocyanuric acid derivative, a carbonyl compound having a nitrogen atom-containing group, and a vinyl compound having a nitrogen atom-containing group. , an epoxy compound having a nitrogen atom-containing group, an alkoxysilane compound having a nitrogen atom-containing group, a protective amine compound having a nitrogen atom-containing group and capable of forming primary or secondary amines, and the like.

In the coupling agent having a nitrogen atom-containing group, the nitrogen atom-containing functional group preferably includes a functional group derived from an amine compound having no active hydrogen, and the amine compound is, for example, a tertiary amine compound. , and a protected amine compound in which the active hydrogen described above is substituted with a protecting group. Examples of the compound capable of forming another nitrogen atom-containing functional group include an imine compound represented by the general formula -N=C and an alkoxysilane compound bonded to the nitrogen atom-containing group.

Although not limited to the following as an isocyanate compound which is a coupling agent which has a nitrogen atom containing group, For example, 2, 4- tolylene diisocyanate, 2, 6-tolylene diisocyanate, diphenylmethane diisocyanate, Polymeric type diphenyl Methane diisocyanate (C-MDI), phenyl isocyanate, isophorone diisocyanate, hexamethylene diisocyanate, butyl isocyanate, 1,3,5-benzene triisocyanate, etc. are mentioned.

Although not limited to the following as an isocyanuric acid derivative which is a coupling agent which has a nitrogen atom containing group, For example, 1,3,5-tris(3-trimethoxysilylpropyl)isocyanurate, 1,3, 5-tris(3-triethoxysilylpropyl)isocyanurate, 1,3,5-tri(oxiran-2-yl)-1,3,5-triazinane-2,4,6-trione , 1,3,5-tris(isocyanatomethyl)-1,3,5-triazinane-2,4,6-trione, 1,3,5-trivinyl-1,3,5-triazinane -2,4,6-trione etc. are mentioned.

Although not limited to the following as a carbonyl compound which is a coupling agent which has a nitrogen atom containing group, For example, 1, 3- dimethyl- 2-imidazolidinone, 1-methyl-3-ethyl-2- imidazolidinone, , 1-methyl-3- (2-methoxyethyl) -2-imidazolidinone, N-methyl-2-pyrrolidone, N-methyl-2-piperidone, N-methyl-2-quinolone, 4 , 4'-bis (diethylamino) benzophenone, 4,4'-bis (dimethylamino) benzophenone, methyl-2-pyridyl ketone, methyl-4-pyridyl ketone, propyl-2-pyridyl ketone, Di-4-pyridylketone, 2-benzoylpyridine, N,N,N',N'-tetramethyl urea, N,N-dimethyl-N',N'-diphenyl urea, N,N-diethyl methyl bamate, N,N-diethylacetamide, N,N-dimethyl-N',N'-dimethylaminoacetamide, N,N-dimethylpicolinic acid amide, N,N-dimethylisonicotinic acid amide, etc. can

Although not limited to the following as a vinyl compound which is a coupling agent which has a nitrogen atom containing group, For example, N,N- dimethyl acrylamide, N,N- dimethyl methacrylamide, N-methylmaleimide, N-methylphthal Mead, N,N-bistrimethylsilylacrylamide, morpholinoacrylamide, 3-(2-dimethylaminoethyl)styrene, (dimethylamino)dimethyl-4-vinylphenylsilane, 4,4'-vinylidenebis( N,N-dimethylaniline), 4,4'-vinylidenebis(N,N-diethylaniline), 1,1-bis(4-morpholinophenyl)ethylene, 1-phenyl-1-(4- N,N-dimethylaminophenyl)ethylene etc. are mentioned.

Examples of the epoxy compound as a coupling agent having a nitrogen atom-containing group include, but are not limited to, an epoxy group-containing hydrocarbon compound bonded to an amino group, and an epoxy group-containing hydrocarbon compound bonded to an ether group.

Although not limited to the following as such an epoxy compound, For example, the epoxy compound represented by General formula (i) is mentioned.

In the formula (i), R is a divalent or higher hydrocarbon group, or a polar group having oxygen such as ether, epoxy or ketone, a polar group having sulfur such as thioether or thioketone, a tertiary amino group, or nitrogen such as an imino group It is a divalent or more organic group which has at least 1 type of polar group selected from the group which consists of a polar group which has.

The divalent or higher hydrocarbon group is a saturated or unsaturated linear, branched or cyclic hydrocarbon group, and includes an alkylene group, an alkenylene group, a phenylene group, and the like. Preferably, it is a C1-C20 hydrocarbon group. For example, methylene, ethylene, butylene, cyclohexylene, 1,3-bis(methylene)-cyclohexane, 1,3-bis(ethylene)-cyclohexane, o-, m-, p-phenylene, m-, p-xylene, bis(phenylene)-methane, etc. are mentioned.

In the formula (i), R ¹ and R ⁴ are a hydrocarbon group having 1 to 10 carbon atoms, and R ¹ and R ⁴ may be the same as or different from each other.

In the formula (i), R ² and R ⁵ are hydrogen or a hydrocarbon group having 1 to 10 carbon atoms, and R ² and R ⁵ may be the same as or different from each other.

In said formula (i), R<^3> is a C1-C10 hydrocarbon group, or a structure of following formula (ii).

R ¹ , R ² , and R ³ may be a cyclic structure bonded to each other.

In addition, when R ³ is a hydrocarbon group, or may be an annular structure bonded to each other and R. In the case of the above-described cyclic structure, the form in which N and R bonded to ^{R 3 are directly bonded may be used.}

In the formula (i) above, n is an integer of 1 or more, and m is 0 or an integer of 1 or more.

In the formula (ii), R ^1, R ² is defined as with R ^1, R ² of formula (i), R ^1, R ² will be the same or different from each other.

As an epoxy compound which is a coupling agent which has a nitrogen atom containing group, it is preferable to have an epoxy group containing hydrocarbon group, More preferably, it has a glycidyl group containing hydrocarbon group.

Although it does not specifically limit as an epoxy-group containing hydrocarbon group couple|bonded with an amino group or an ether group, For example, a glycidylamino group, a diglycidylamino group, or a glycidoxy group is mentioned. A more preferable molecular structure is an epoxy group-containing compound each having a glycidylamino group or a diglycidylamino group and a glycidoxy group, and a compound represented by the following general formula (iii) is exemplified.

In said formula (iii), R is defined similarly to R of said formula (i), and R<^6> is a C1-C10 hydrocarbon group or a structure of following formula (iv).

When R ⁶ is a hydrocarbon group, it may have a cyclic structure when it is mutually bonded to R, and in that case, N and R bonded to ^{R 6 may be directly bonded.}

In formula (iii), n is an integer of 1 or more, and m is 0 or an integer of 1 or more.

As an epoxy compound which is a coupling agent which has a nitrogen atom containing group, Especially preferably, it is a compound which has one or more diglycidylamino groups and one or more glycidoxy groups in a molecule|numerator.

Although it is not limited to the following as an epoxy compound used as a coupling agent which has a nitrogen atom containing group, For example, N,N- diglycidyl-4-glycidoxyaniline, 1-N,N- diglycidyl Aminomethyl-4-glycidoxy-cyclohexane, 4-(4-glycidoxyphenyl)-(N,N-diglycidyl)aniline, 4-(4-glycidoxyphenoxy)-(N, N-diglycidyl)aniline, 4-(4-glycidoxybenzyl)-(N,N-diglycidyl)aniline, 4-(N,N'-diglycidyl-2-piperazinyl) )-Glycidoxybenzene, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, N,N,N',N'-tetraglycidyl-m-xylenediamine, 4,4 -Methylene-bis(N,N-diglycidylaniline), 1,4-bis(N,N-diglycidylamino)cyclohexane, N,N,N',N'-tetraglycidyl- p-phenylenediamine, 4,4'-bis(diglycidylamino)benzophenone, 4-(4-glycidylpiperazinyl)-(N,N-diglycidyl)aniline, 2-[2 -(N,N-diglycidylamino)ethyl]-1-glycidylpyrrolidine, N,N-diglycidylaniline, 4,4'-diglycidyl-dibenzylmethylamine, N, N-diglycidylaniline, N,N-diglycidylorthotoluidine, N,N-diglycidylaminomethylcyclohexane, etc. are mentioned. Among these, N,N-diglycidyl-4-glycidoxyaniline and 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane are mentioned as especially preferable.

Although it is not limited to the following as an alkoxysilane compound which is a coupling agent which has a nitrogen atom containing group, For example, 3-dimethylaminopropyl trimethoxysilane, 3-dimethylamino propylmethyl dimethoxysilane, 3-diethylamino propyl tri Ethoxysilane, 3-morpholinopropyltrimethoxysilane, 3-piperidinopropyltriethoxysilane, 3-hexamethyleneiminopropylmethyldiethoxysilane, 3-(4-methyl-1-piperazino ) propyltriethoxysilane, 1-[3-(triethoxysilyl)-propyl]-3-methylhexahydropyrimidine, 3-(4-trimethylsilyl-1-piperazino)propyltriethoxysilane, 3-(3-triethylsilyl-1-imidazolidinyl)propylmethyldiethoxysilane, 3-(3-trimethylsilyl-1-hexahydropyrimidinyl)propyltrimethoxysilane, 3-dimethylamino-2 -(dimethylaminomethyl)propyltrimethoxysilane, bis(3-dimethoxymethylsilylpropyl)-N-methylamine, bis(3-trimethoxysilylpropyl)-N-methylamine, bis(3-trie Toxysilylpropyl)methylamine, tris(trimethoxysilyl)amine, tris(3-trimethoxysilylpropyl)amine, N,N,N',N'-tetra(3-trimethoxysilylpropyl)ethylenediamine , 3-isocyanatopropyltrimethoxysilane, 3-cyanopropyltrimethoxysilane, 2,2-dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza-2-silacyclopentane , 2,2-diethoxy-1-(3-triethoxysilylpropyl)-1-aza-2-silacyclopentane, 2,2-dimethoxy-1-(4-trimethoxysilylbutyl)-1 -aza-2-silacyclohexane, 2,2-dimethoxy-1-(3-dimethoxymethylsilylpropyl)-1-aza-2-silacyclopentane, 2,2-dimethoxy-1-phenyl-1 -aza-2-silacyclopentane, 2,2-diethoxy-1-butyl-1-aza-2-silacyclopentane, 2,2-dimethoxy-1-methyl-1-aza-2-silacyclopentane , 2,2-dimethoxy-8-(4-methylpiperazinyl)methyl-1,6-dioxa-2-silacyclooctane, 2,2-dimethoxy-8-(N,N-diethylamino ) methyl-1,6-dioxa-2-silacyclooctane and the like.

As a protective amine compound that is a coupling agent having a nitrogen atom-containing group and can form primary or secondary amine, the compound having an unsaturated bond and a protective amine in its molecule is not limited to the following, but for example, 4,4'-vinylidenebis[N,N-bis(trimethylsilyl)aniline], 4,4'-vinylidenebis[N,N-bis(triethylsilyl)aniline], 4,4'-vinylidene bis[N,N-bis(t-butyldimethylsilyl)aniline], 4,4'-vinylidenebis[N-methyl-N-(trimethylsilyl)aniline], 4,4'-vinylidenebis[N- ethyl-N-(trimethylsilyl)aniline], 4,4'-vinylidenebis[N-methyl-N-(triethylsilyl)aniline], 4,4'-vinylidenebis[N-ethyl-N-( triethylsilyl)aniline], 4,4'-vinylidenebis[N-methyl-N-(t-butyldimethylsilyl)aniline], 4,4'-vinylidenebis[N-ethyl-N-(t-) butyldimethylsilyl)aniline], 1-[4-N,N-bis(trimethylsilyl)aminophenyl]-1-[4-N-methyl-N-(trimethylsilyl)aminophenyl]ethylene, 1-[4- N,N-bis(trimethylsilyl)aminophenyl]-1-[4-N,N-dimethylaminophenyl]ethylene; and the like.

A coupling agent having a nitrogen atom-containing group, a protected amine compound capable of forming a primary or secondary amine, and a compound having an alkoxysilane and a protected amine in the molecule, is not limited to the following, for example, N,N-bis(trimethylsilyl)aminopropyltrimethoxysilane, N,N-bis(trimethylsilyl)aminopropylmethyldimethoxysilane, N,N-bis(trimethylsilyl)aminopropyltriethoxysilane, N, N-bis(trimethylsilyl)aminopropylmethyldiethoxysilane, N,N-bis(trimethylsilyl)aminoethyltrimethoxysilane, N,N-bis(trimethylsilyl)aminoethylmethyldiethoxysilane, N,N- Bis(triethylsilyl)aminopropylmethyldiethoxysilane, 3-(4-trimethylsilyl-1-piperazino)propyltriethoxysilane, 3-(3-triethylsilyl-1-imidazolidinyl)propyl Methyldiethoxysilane, 3-(3-trimethylsilyl-1-hexahydropyrimidinyl)propyltrimethoxysilane, 2,2-dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza- 2-Silacyclopentane, 2,2-diethoxy-1-(3-triethoxysilylpropyl)-1-aza-2-silacyclopentane, 2,2-dimethoxy-1-(4-trimethoxy Silylbutyl)-1-aza-2-silacyclohexane, 2,2-dimethoxy-1-(3-dimethoxymethylsilylpropyl)-1-aza-2-silacyclopentane, 2,2-dimethoxy- 1-phenyl-1-aza-2-silacyclopentane, 2,2-diethoxy-1-butyl-1-aza-2-silacyclopentane, 2,2-dimethoxy-1-methyl-1-aza- 2-Silacyclopentane, N-(1,3-dimethylbutylidene)-3-(triethoxysilyl)-1-propanamine, N-(1-methylethylidene)-3-(triethoxy Silyl)-1-propanamine, N-ethylidene-3-(triethoxysilyl)-1-propanamine, N-(1-methylpropylidene)-3-(triethoxysilyl)-1-propanamine , N-(4-N,N-dimethylaminobenzylidene)-3-(triethoxysilyl)-1-propanamine, and the like, and N-(1-methylpropylidene)-3-(trie). Toxysilyl)-1-propanamine, N-(1,3-dimethylbutylidene)-3-(triethoxysilyl)-1-propanamine, 3-(benzylideneamino)propyltrimethoxysilane, 3 -(benzylideneamino)propyltrimethoxysilane, 3-(benzylideneamino)propylt and ethoxysilane and 3-(benzylideneamino)propyltripropylsilane.

Particularly preferably, the alkoxysilane compound as a coupling agent having a nitrogen atom-containing group is not limited to the following, for example, tris(3-trimethoxysilylpropyl)amine, tris(3-triethoxysilylpropyl) amine, tris(3-tripropoxysilylpropyl)amine, bis(3-trimethoxysilylpropyl)-[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]amine; Tetrakis(3-trimethoxysilylpropyl)-1,3-propanediamine, tris(3-trimethoxysilylpropyl)-[3-(1-methoxy-2-trimethylsilyl-1-sila-2- Azacyclopentane)propyl]-1,3-propanediamine, tris(3-trimethoxysilylpropyl)-[3-(1-methoxy-2-methyl-1-sila-2-azacyclopentane)propyl] -1,3-propanediamine, bis(3-triethoxysilylpropyl)-[3-(2,2-diethoxy-1-aza-2-silacyclopentane)propyl]-[3-(1-e Toxy-2-trimethylsilyl-1-sila-2-azacyclopentane)propyl]-1,3-propanediamine, tetrakis(3-trimethoxysilylpropyl)-1,3-bisaminomethylcyclohexane, tris (3-trimethoxysilylpropyl)-[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]-1,3-bisaminomethylcyclohexane, tetrakis(3-tri Methoxysilylpropyl)-1,6-hexamethylenediamine, pentakis(3-trimethoxysilylpropyl)-diethylenetriamine, tris(3-trimethoxysilylpropyl)-methyl-1,3-propanediamine , tetrakis[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]silane, bis(3-trimethoxysilylpropyl)-bis[3-(2,2-dimethoxy -1-aza-2-silacyclopentane)propyl]silane, tris[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]-(3-trimethoxysilylpropyl)silane , tris[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]-[3-(1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) Propyl]silane, 3-tris[2-(2,2-dimethoxy-1-aza-2-silacyclopentane)ethoxy]silyl-1-trimethoxysilylpropane, 1-[3-(1-methyl Toxy-2-trimethylsilyl-1-sila-2-azacyclopentane)propyl]-3,4,5-tris(3-trimethoxysilylpropyl )-Cyclohexane, 1-[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]-3,4,5-tris(3-trimethoxysilylpropyl)-cyclohexane , 3,4,5-tris(3-trimethoxysilylpropyl)-cyclohexyl-[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]ether, (3-tri Methoxysilylpropyl)phosphate, bis(3-trimethoxysilylpropyl)-[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]phosphate, bis[3-(2, 2-dimethoxy-1-aza-2-silacyclopentane)propyl]-(3-trimethoxysilylpropyl)phosphate and tris[3-(2,2-dimethoxy-1-aza-2-silacyclopentane) ) propyl] phosphate.

[Coupling agent represented by formula (a)]

In the method for producing the branched conjugated diene-based polymer of the present embodiment, the active terminal of the conjugated diene-based polymer having a branched structure introduced therein, obtained through the polymerization step and branching step described above, is expressed by the following formula (a) It is preferable to carry out the reaction step of reacting the compound [A] to be used.

A compound [A] is a compound which has a total of 2 or more alkoxysilyl groups containing a nitrogen atom, The structure represented by X in Formula (a) is a structure represented by said Formula (b) - (e).

By performing the reaction step using the coupling agent represented by the formula (a), it is possible to obtain a branched conjugated diene-based polymer having a high branching index of the polymer chain and modified by a group interacting with silica.

In formula (a), R ¹ to R ⁴ , each independently represent an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and R ⁵ to R ⁶ are each independently alkylene having 1 to 20 carbon atoms. represents the group.

m and n are integers of 1 to 3, and in formula (a), a plurality of R ¹ to R ⁶ , m, and n may be the same or different.

In the formula (a), X is represented by any of the following general formulas (b) to (e).

In the formula (b), R ⁷ represents a hydrocarbon group having 1 to 20 carbon atoms, and the hydrocarbon group may have a partially branched structure or a cyclic structure. R ⁸ represents a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and in the case of a hydrocarbon group, it may have a partially branched structure or a cyclic structure.

In formula (c), R ⁹ represents a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and in the case of a hydrocarbon group, it may have a partially branched structure or a cyclic structure.

In the formula (d), R ¹⁰ represents a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and in the case of a hydrocarbon group, it may have a partially branched structure or a cyclic structure.

In formula (e), R ¹¹ to R ¹⁴ each independently represent an alkylene group having 1 to 20 carbon atoms.

R ¹⁵ to R ¹⁸ each independently represent an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, l and o each independently represent an integer of 1 to 3, R ^{15 when there is a plurality of them} to R ¹⁸ are each independent.

Although not limited to the following as compound [A] used in a denaturation process, ie, reaction process, For example, the compound etc. which are represented by each of following formula (A-1) - Formula (A-16) are mentioned. .

In addition, a compound [A] may be used individually by 1 type, and may be used in combination of 2 or more type.

<Compound [A] used in the modification step: Formulas (A-1) to (A-16)>

In the formulas (A-1) to (A-16), Et is an ethyl group, and Me is a methyl group.

The reaction of the conjugated diene polymer having an active terminal obtained in the branching step and the compound [A] represented by the formula (a) can be carried out, for example, as a solution reaction.

From the viewpoint of sufficiently advancing the coupling reaction, the usage ratio of compound [A] (in the case of using two or more types) is 0.01 mol or more with respect to 1 mol of the metal atom involved in the polymerization of the polymerization initiator. It is preferable, and it is more preferable to set it as 0.05 mol or more. Moreover, about an upper limit, in order to avoid excess addition, it is preferable to set it as less than 2.0 mol with respect to 1 mol of the metal atom which is involved in polymerization which a polymerization initiator has, and it is more preferable to set it as less than 1.5 mol.

The temperature of the coupling reaction using the compound [A] represented by the formula (a) is usually the same as that of the polymerization reaction, preferably -20°C to 150°C, and more preferably 0 to 120°C. Do. When the reaction temperature is low, the viscosity of the polymer after the coupling reaction tends to increase, and when the reaction temperature is high, the polymerization active terminal is easily deactivated. The reaction time is preferably 1 minute to 5 hours, and more preferably 2 minutes to 1 hour.

In the reaction of the conjugated diene polymer having an active terminal obtained in the branching step and the compound [A] represented by the formula (a), other modifiers or coupling agents may be used together with the compound [A].

The other modifier or coupling agent is not particularly limited as long as it is a compound capable of reacting with the active terminal of the conjugated diene polymer obtained by the polymerization step and the branching step, and a compound known as a modifier or coupling agent for the conjugated diene polymer. can be used

When using another modifier or coupling agent, it is preferable to set it as 10 mol% or less, and, as for the usage ratio, it is more preferable to set it as 5 mol% or less.

<Branched conjugated diene-based polymer obtained through polymerization process, branching process, and reaction process>

The branched conjugated diene-based polymer obtained through the above-described reaction step, particularly, the step of reacting a coupling agent in the method for producing a branched conjugated diene-based polymer of the present embodiment, has the following general formula (i) or general formula It is preferable to include the structure derived from the compound which has a nitrogen-atom containing group represented by any of (A)-(C).

In the formula (i), R is a divalent or higher hydrocarbon group, or a polar group having oxygen such as ether, epoxy or ketone, a polar group having sulfur such as thioether or thioketone, a tertiary amino group, or nitrogen such as an imino group It is a divalent or more organic group which has at least 1 sort(s) of polar group selected from the polar group which has.

The divalent or higher hydrocarbon group is a saturated or unsaturated linear, branched, or cyclic hydrocarbon group, and includes an alkylene group, an alkenylene group, a phenylene group, and the like. Preferably, it is a C1-C20 hydrocarbon group. For example, methylene, ethylene, butylene, cyclohexylene, 1,3-bis(methylene)-cyclohexane, 1,3-bis(ethylene)-cyclohexane, o-, m-, p-phenylene, m-, p-xylene, bis(phenylene)-methane, etc. are mentioned.

In the formula (i), R ¹ and R ⁴ are a hydrocarbon group having 1 to 10 carbon atoms, and R ¹ and R ⁴ may be the same as or different from each other.

In the formula (i), R ² and R ⁵ are hydrogen or a hydrocarbon group having 1 to 10 carbon atoms, and R ² and R ⁵ may be the same as or different from each other.

In said formula (i), R<^3> is a C1-C10 hydrocarbon group, or a structure of following formula (ii).

R ¹ , R ² , and R ³ may be a cyclic structure bonded to each other.

In addition, when R ³ is a hydrocarbon group, or may be an annular structure bonded to each other and R. In the case of the above-described cyclic structure, the form in which N and R bonded to ^{R 3 are directly bonded may be used.}

In the formula (i) above, n is an integer of 1 or more, and m is 0 or an integer of 1 or more.

In the formula (ii), R ^1, R ² is defined as with R ^1, R ² of formula (i), R ^1, R ² will be the same or different from each other.

(In formula (A), R ¹ to R ⁴ each independently represent an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, R ⁵ represents an alkylene group having 1 to 10 carbon atoms, R ⁶ represents a C1-C20 alkylene group.

m represents the integer of 1 or 2, n represents the integer of 2 or 3, and (m+n) represents the integer of 4 or more. In the case of two or more, R ¹ to R ⁴ are each independent.)

(In formula (B), R ¹ to R ⁶ each independently represent an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and R ⁷ to R ⁹ are each independently, each independently having 1 to 20 carbon atoms represents an alkylene group.

m, n, and 1 each independently represent the integer of 1-3, and (m+n+1) represents the integer of 4 or more. In the case of two or more, R ¹ to R ⁶ are each independent.)

(In the formula (C), R ¹² to R ¹⁴ each independently represent a single bond or an alkylene group having 1 to 20 carbon atoms, and R ¹⁵ to R ¹⁸ and R ²⁰ are each independently each independently a single bond or an alkylene group having 1 to 20 carbon atoms. represents an alkyl group, R ¹⁹ and R ²² each independently represent an alkylene group ^{having 1 to 20 carbon atoms, and R 21} represents an alkyl group or trialkylsilyl group having 1 to 20 carbon atoms.

m represents the integer of 1-3, and p represents 1 or 2.

Each of R ¹² to R ²² , m and p in the case of two or more are independent and may be the same or different.

i represents the integer of 0-6, j represents the integer of 0-6, k represents the integer of 0-6, (i+j+k) is the integer of 4-10.

A represents a hydrocarbon group having 1 to 20 carbon atoms, or an organic group having at least one atom selected from the group consisting of an oxygen atom, a nitrogen atom, a silicon atom, a sulfur atom and a phosphorus atom, and having no active hydrogen.)

The coupling agent having a nitrogen atom-containing group represented by the formula (A) is not limited to the following, for example, 2,2-dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza- 2-Silacyclopentane, 2,2-diethoxy-1-(3-triethoxysilylpropyl)-1-aza-2-silacyclopentane, 2,2-dimethoxy-1-(4-trimethoxy Silylbutyl)-1-aza-2-silacyclohexane, 2,2-dimethoxy-1-(5-trimethoxysilylpentyl)-1-aza-2-silacycloheptane, 2,2-dimethoxy- 1-(3-dimethoxymethylsilylpropyl)-1-aza-2-silacyclopentane, 2,2-diethoxy-1-(3-diethoxyethylsilylpropyl)-1-aza-2-silacyclopentane , 2-Methoxy, 2-methyl-1- (3-trimethoxysilylpropyl) -1-aza-2-silacyclopentane, 2-ethoxy, 2-ethyl-1- (3-triethoxysilyl Propyl)-1-aza-2-silacyclopentane, 2-methoxy, 2-methyl-1-(3-dimethoxymethylsilylpropyl)-1-aza-2-silacyclopentane and 2-ethoxy, 2 -ethyl-1-(3-diethoxyethylsilylpropyl)-1-aza-2-silacyclopentane.

Among these, it is preferable that m represents 2 and n represents 3 from a viewpoint of the reactivity and interaction of the functional group of the coupling agent which has a nitrogen atom containing group, and inorganic fillers, such as silica, and workability. Specifically, 2,2-dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza-2-silacyclopentane and 2,2-diethoxy-1-(3-triethoxysilylpropyl) )-1-aza-2-silacyclopentane is preferred.

Although it does not specifically limit about the reaction temperature, reaction time, etc. at the time of making the coupling agent which has a nitrogen-atom containing group represented by said formula (A) react with polymerization active terminal, At 0 degreeC or more and 120 degrees C or less, 30 second or more It is preferable to react.

The total number of moles of alkoxy groups bonded to silyl groups in the compound of the coupling agent having a nitrogen atom-containing group represented by the formula (A) is 0.6 times or more and 3.0 times the number of moles added to the alkali metal compound and/or alkaline earth metal compound of the polymerization initiator. It is preferable that it is the range used as below, it is more preferable that it is the range used as 0.8 times or more and 2.5 times or less, It is more preferable that it is the range used as 0.8 times or more and 2.0 times or less. From the viewpoint of obtaining a sufficient denaturation rate and molecular weight and branching structure of the obtained branched conjugated diene-based polymer, it is preferable to set it to 0.6 times or more, and to improve processability, the polymer ends are coupled to each other to obtain a branched conjugated diene-based polymer component In addition to being preferable to obtain, it is preferable to set it as 3.0 times or less from a viewpoint of coupling agent cost.

The number of moles of the polymerization initiator is preferably 3.0 moles or more, and more preferably 4.0 times moles or more with respect to the number of moles of the coupling agent having a nitrogen atom-containing group represented by the formula (A).

Examples of the coupling agent having a nitrogen atom-containing group represented by the formula (B) include, but are not limited to, tris(3-trimethoxysilylpropyl)amine and tris(3-methyldimethoxysilylpropyl)amine. , tris(3-triethoxysilylpropyl)amine, tris(3-methyldiethoxysilylpropyl)amine, tris(trimethoxysilylmethyl)amine, tris(2-trimethoxysilylethyl)amine and tris(4 -trimethoxysilylbutyl)amine is mentioned.

Among these, it is preferable that n, m, and 1 all represent 3 in said Formula (B) from a viewpoint of the reactivity and interaction of the functional group of a coupling agent, and inorganic fillers, such as silica, and a viewpoint of processability. Preferred specific examples include tris(3-trimethoxysilylpropyl)amine and tris(3-triethoxysilylpropyl)amine.

When the coupling agent having a nitrogen atom-containing group represented by the formula (B) is reacted with the active terminal of the conjugated diene-based polymer obtained in the branching step, the reaction temperature, reaction time, etc. are not particularly limited, but 0 It is preferable to make it react for 30 second or more at °C or more and 120 °C or less.

It is preferable that the total number of moles of alkoxy groups bonded to silyl groups in the compound of the coupling agent represented by the formula (B) is in the range of 0.6 times or more and 3.0 times or less of the moles of lithium constituting the polymerization initiator, 0.8 times or more. It is more preferable that it is the range used as 2.5 times or less, and it is still more preferable that it is the range used as 0.8 times or more and 2.0 times or less. In the branched conjugated diene-based polymer obtained by the production method of the present embodiment, from the viewpoint of obtaining a sufficient modification rate, molecular weight, and branched structure, it is preferable to set it to 0.6 times or more, and the polymer ends are coupled to each other to improve workability. In addition to being preferable to obtain a branched conjugated diene polymer component, it is preferable to set it as 3.0 times or less from a viewpoint of coupling agent cost.

Preferably the number of moles of a polymerization initiator is 4.0 times mole or more, More preferably, it is 5.0 times mole or more with respect to the mole number of the coupling agent which has a nitrogen-atom containing group represented by said Formula (B).

In the formula (C), A is preferably represented by any of the following general formulas (II) to (V).

(In formula (II), B ¹ represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, and a represents an integer of 1 to 10. B ¹ in the presence of two or more is each independent.)

(In the formula (III), B ² represents a single bond or a hydrocarbon group ^{having 1 to 20 carbon atoms, B 3} represents an alkyl group having 1 to 20 carbon atoms, and a represents an integer of 1 to 10. There are a plurality of each. B ² and B ^{3 in this case} are each independent.)

(In formula (IV), B ⁴ represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, and a represents an integer of 1 to 10. B ⁴ in the presence of two or more is each independent.)

(In formula (V), B ⁵ represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, and a represents an integer of 1 to 10. B ⁵ in the presence of two or more is each independent.)

In the formula (C), the coupling agent having a nitrogen atom-containing group in the case where A is represented by the formula (II) is not limited to the following, for example, tris(3-trimethoxysilylpropyl)amine; Bis(3-trimethoxysilylpropyl)-[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]amine, bis[3-(2,2-dimethoxy-1- Aza-2-silacyclopentane)propyl]-(3-trimethoxysilylpropyl)amine, tris[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]amine, tris( 3-ethoxysilylpropyl)amine, bis(3-triethoxysilylpropyl)-[3-(2,2-diethoxy-1-aza-2-silacyclopentane)propyl]amine, bis[3-( 2,2-diethoxy-1-aza-2-silacyclopentane)propyl]-(3-triethoxysilylpropyl)amine, tris[3-(2,2-diethoxy-1-aza-2-sila) Cyclopentane)propyl]amine, tetrakis(3-trimethoxysilylpropyl)-1,3-propanediamine, tris(3-trimethoxysilylpropyl)-[3-(2,2-dimethoxy-1- Aza-2-silacyclopentane)propyl]-1,3-propanediamine, bis(3-trimethoxysilylpropyl)-bis[3-(2,2-dimethoxy-1-aza-2-silacyclopentane) )propyl]-1,3-propanediamine, tris[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]-(3-trimethoxysilylpropyl)-1,3- Propanediamine, tetrakis[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]-1,3-propanediamine, tris(3-trimethoxysilylpropyl)-[3- (1-Methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane)propyl]-1,3-propanediamine, bis(3-trimethoxysilylpropyl)-[3-(2,2-) dimethoxy-1-aza-2-silacyclopentane)propyl]-[3-(1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane)propyl]-1,3-propanediamine; Bis[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]-(3-trimethoxysilylpropyl)-[3-(1-methoxy-2-trimethylsilyl-1) -Sila-2-azacyclopentane)propyl]-1,3-propanediamine, tris[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]-[3-(1- methoxy- 2-trimethylsilyl-1-sila-2-azacyclopentane)propyl]-1,3-propanediamine, tetrakis(3-triethoxysilylpropyl)-1,3-propanediamine, tris(3-trie Toxysilylpropyl)-[3-(2,2-diethoxy-1-aza-2-silacyclopentane)propyl]-1,3-propanediamine, bis(3-triethoxysilylpropyl)-bis[3 -(2,2-diethoxy-1-aza-2-silacyclopentane)propyl]-1,3-propanediamine, tris[3-(2,2-diethoxy-1-aza-2-silacyclopentane) )propyl]-(3-triethoxysilylpropyl)-1,3-propanediamine, tetrakis[3-(2,2-diethoxy-1-aza-2-silacyclopentane)propyl]-1,3 -Propanediamine, tris(3-triethoxysilylpropyl)-[3-(1-ethoxy-2-trimethylsilyl-1-sila-2-azacyclopentane)propyl]-1,3-propanediamine, bis (3-triethoxysilylpropyl)-[3-(2,2-diethoxy-1-aza-2-silacyclopentane)propyl]-[3-(1-ethoxy-2-trimethylsilyl-1- Sila-2-azacyclopentane)propyl]-1,3-propanediamine, bis[3-(2,2-diethoxy-1-aza-2-silacyclopentane)propyl]-(3-triethoxysilyl Propyl)-[3-(1-ethoxy-2-trimethylsilyl-1-sila-2-azacyclopentane)propyl]-1,3-propanediamine, tris[3-(2,2-diethoxy-1) -aza-2-silacyclopentane)propyl]-[3-(1-ethoxy-2-trimethylsilyl-1-sila-2-azacyclopentane)propyl]-1,3-propanediamine, tetrakis (3 -trimethoxysilylpropyl)-1,3-bisaminomethylcyclohexane, tris(3-trimethoxysilylpropyl)-[3-(2,2-dimethoxy-1-aza-2-silacyclopentane) Propyl]-1,3-bisaminomethylcyclohexane, bis(3-trimethoxysilylpropyl)-bis[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]-1 ,3-bisaminomethylcyclohexane, tris[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]-(3-trimethoxysilylpropyl)-1,3-bisamino Methylcyclohexane, tetrakis[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]-1,3-propanediamine, tris(3-trimethoxysilylpropyl)-[3 -(1-methoxy-2-trime Tylsilyl-1-sila-2-azacyclopentane)propyl]-1,3-bisaminomethylcyclohexane, bis(3-trimethoxysilylpropyl)-[3-(2,2-dimethoxy-1- Aza-2-silacyclopentane)propyl]-[3-(1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane)propyl]-1,3-bisaminomethylcyclohexane, bis[ 3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]-(3-trimethoxysilylpropyl)-[3-(1-methoxy-2-trimethylsilyl-1-sila) -2-azacyclopentane)propyl]-1,3-bisaminomethylcyclohexane, tris[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]-[3-(1 -Methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane)propyl]-1,3-bisaminomethylcyclohexane, tetrakis(3-triethoxysilylpropyl)-1,3-propanediamine , tris(3-triethoxysilylpropyl)-[3-(2,2-diethoxy-1-aza-2-silacyclopentane)propyl]-1,3-bisaminomethylcyclohexane, bis(3- Triethoxysilylpropyl)-bis[3-(2,2-diethoxy-1-aza-2-silacyclopentane)propyl]-1,3-bisaminomethylcyclohexane, tris[3-(2,2) -diethoxy-1-aza-2-silacyclopentane)propyl]-(3-triethoxysilylpropyl)-1,3-propanediamine, tetrakis[3-(2,2-diethoxy-1-aza) -2-Silacyclopentane)propyl]-1,3-propanediamine, tris(3-triethoxysilylpropyl)-[3-(1-ethoxy-2-trimethylsilyl-1-sila-2-azacyclo) Pentane)propyl]-1,3-bisaminomethylcyclohexane, bis(3-triethoxysilylpropyl)-[3-(2,2-diethoxy-1-aza-2-silacyclopentane)propyl]- [3-(1-Ethoxy-2-trimethylsilyl-1-sila-2-azacyclopentane)propyl]-1,3-bisaminomethylcyclohexane, bis[3-(2,2-diethoxy-1) -aza-2-silacyclopentane)propyl]-(3-triethoxysilylpropyl)-[3-(1-ethoxy-2-trimethylsilyl-1-sila-2-azacyclopentane)propyl]-1 ,3-Bisaminomethylcyclohexane, tris[3-(2,2-diethoxy-1-aza-2-silacyclopentane)propyl]-[3-(1-ethoxy-2-trimethylsilyl-1- sila-2-azacyclopentane)propyl]-1,3 -bisaminomethylcyclohexane, tetrakis(3-trimethoxysilylpropyl)-1,6-hexamethylenediamine, and pentakis(3-trimethoxysilylpropyl)-diethylenetriamine are mentioned.

In the formula (C), the coupling agent having a nitrogen atom-containing group in the case where A is represented by the formula (III) is not limited to the following, for example, tris(3-trimethoxysilylpropyl)-methyl -1,3-propanediamine, bis(2-trimethoxysilylpropyl)-[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]-methyl-1,3-propane Diamine, bis[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]-(3-trimethoxysilylpropyl)-methyl-1,3-propanediamine, tris(3- Triethoxysilylpropyl)-methyl-1,3-propanediamine, bis(2-triethoxysilylpropyl)-[3-(2,2-diethoxy-1-aza-2-silacyclopentane)propyl] -Methyl-1,3-propanediamine, bis[3-(2,2-diethoxy-1-aza-2-silacyclopentane)propyl]-(3-triethoxysilylpropyl)-methyl-1,3 -propanediamine, N1,N1'-(propane-1,3-diyl)bis(N1-methyl-N3,N3-bis(3-(trimethoxysilyl)propyl)-1,3-propanediamine) and N1 -(3-(bis(3-(trimethoxysilyl)propyl)amino)propyl)-N1-methyl-N3-(3-(methyl(3-(trimethoxysilyl)propyl)amino)propyl)-N3 -(3-(trimethoxysilyl)propyl)-1,3-propanediamine is mentioned.

In the formula (C), the coupling agent having a nitrogen atom-containing group in the case where A is represented by the formula (IV) is not limited to the following, for example, tetrakis[3-(2,2-dimethoxy) -1-aza-2-silacyclopentane)propyl]silane, tris[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]-(3-trimethoxysilylpropyl)silane , tris[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]-[3-(1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) Propyl]silane, bis(3-trimethoxysilylpropyl)-bis[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]silane, (3-trimethoxysilyl)- [3-(1-Methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane)-bis[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]silane , bis[3-(1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane)-bis[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl ]silane, tris(3-trimethoxysilylpropyl)-[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]silane, bis(3-trimethoxysilylpropyl)- [3-(1-Methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane)propyl]-[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl] Silane, bis[3-(1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane)propyl]-bis(3-trimethoxysilylpropyl)silane and bis(3-trimethoxysilyl propyl)-bis[3-(1-methoxy-2-methyl-1-sila-2-azacyclopentane)propyl]silane.

In the formula (C), the coupling agent having a nitrogen atom-containing group in the case where A is represented by the formula (V) is not limited to the following, for example, 3-tris[2-(2,2-dimethy) Toxy-1-aza-2-silacyclopentane)ethoxy]silyl-1-(2,2-dimethoxy-1-aza-2-silacyclopentane)propane and 3-tris[2-(2,2-) dimethoxy-1-aza-2-silacyclopentane)ethoxy]silyl-1-trimethoxysilylpropane.

In the formula (C), A is preferably represented by a formula (II) or a formula (III), and k represents 0.

The coupling agent having such a nitrogen atom-containing group tends to be easily available, and the abrasion resistance and low hysteresis loss performance when the branched conjugated diene-based polymer obtained by the production method of the present embodiment is used as a vulcanized product is further tends to be superior. The coupling agent having such a nitrogen atom-containing group is not limited to the following, for example, bis(3-trimethoxysilylpropyl)-[3-(2,2-dimethoxy-1-aza-2-silacyclo) Pentane)propyl]amine, tris(3-trimethoxysilylpropyl)amine, tris(3-triethoxysilylpropyl)amine, tris(3-trimethoxysilylpropyl)-[3-(2,2-dimethy oxy-1-aza-2-silacyclopentane)propyl]-1,3-propanediamine, tetrakis[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]-1, 3-propanediamine, tetrakis(3-trimethoxysilylpropyl)-1,3-propanediamine, tetrakis(3-trimethoxysilylpropyl)-1,3-bisaminomethylcyclohexane, tris(3- Trimethoxysilylpropyl)-methyl-1,3-propanediamine and bis[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]-(3-trismethoxysilylpropyl) -methyl-1,3-propanediamine is mentioned.

In the formula (C), A is more preferably represented by formula (II) or formula (III), k represents 0, and in formula (II) or formula (III), a is 2 An integer of -10 is represented.

Thereby, there exists a tendency which becomes more excellent in abrasion resistance and low hysteresis loss performance at the time of vulcanization|vulcanization.

The coupling agent having such a nitrogen atom-containing group is not limited to the following, for example, tetrakis[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]-1,3- Propanediamine, tetrakis(3-trimethoxysilylpropyl)-1,3-propanediamine, tetrakis(3-trimethoxysilylpropyl)-1,3-bisaminomethylcyclohexane and N ₁ -(3- (bis(3-(trimethoxysilyl)propyl)amino)propyl)-N ₁ -methyl-N ₃ -(3-(methyl(3-(trimethoxysilyl)propyl)amino)propyl)-N ₃ - (3-(trimethoxysilyl)propyl)-1,3-propanediamine.

The addition amount of the compound represented by the above formula (C) as a coupling agent having a nitrogen atom-containing group can be adjusted so that the number of moles of the conjugated diene-based polymer to the number of moles of the coupling agent is reacted in a desired stoichiometric ratio, whereby the desired Star-shaped hyperbranched structures tend to be achieved.

Preferably the number of moles of a polymerization initiator is 5.0 times mole or more, More preferably, it is 6.0 times mole or more with respect to the mole number of the coupling agent which has a nitrogen-atom containing group represented by the said formula (C).

In this case, in Formula (C), it is preferable that it is an integer of 5-10, and, as for the functional group number ((m-1)xi+pxj+k) of a coupling agent, it is more preferable that it is an integer of 6-10.

As for the branched conjugated diene polymer obtained by the manufacturing method of this embodiment, the ratio of the polymer which has a nitrogen-atom containing group in the polymer is expressed by a modification rate.

The modification rate is preferably 60% by mass or more, more preferably 65% by mass or more, still more preferably 70% by mass or more, still more preferably 75% by mass or more, still more preferably 80% by mass or more, Especially preferably, it is 82 mass % or more.

When the modification rate is 60% by mass or more, the vulcanized product tends to be excellent in workability, and the vulcanized product tends to be more excellent in wear resistance and low hysteresis loss performance.

<A branched conjugated diene-based polymer obtained through the above reaction step when the compound represented by the formula (a) is used as the coupling agent>

A preferred embodiment of the branched conjugated diene polymer of the present embodiment is a reaction product of a conjugated diene polymer having an active terminal having a branched structure and a compound represented by the following formula (a).

In formula (a), R ¹ to R ⁴ each independently represent an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and R ⁵ to R ⁶ are each independently an alkyl group having 1 to 20 carbon atoms. Represents a rengi.

m and n are integers of 1 to 3, and in formula (a), a plurality of R ¹ to R ⁶ , m, and n may be the same or different.

In the formula (a), X is represented by any of the following general formulas (b) to (e).

In the formula (b), R ⁷ represents a hydrocarbon group having 1 to 20 carbon atoms, and the hydrocarbon group may have a partially branched structure or a cyclic structure. R ⁸ represents a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and in the case of a hydrocarbon group, it may have a partially branched structure or a cyclic structure.

In formula (c), R ⁹ represents a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and in the case of a hydrocarbon group, it may have a partially branched structure or a cyclic structure.

In the formula (d), R ¹⁰ represents a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and in the case of a hydrocarbon group, it may have a partially branched structure or a cyclic structure.

In formula (e), R ¹¹ to R ¹⁴ each independently represent an alkylene group having 1 to 20 carbon atoms.

R ¹⁵ to R ¹⁸ each independently represent an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, l and o each independently represent an integer of 1 to 3, R ^{15 when there is a plurality of them} to R ¹⁸ are each independent.

In the modified conjugated diene-based polymer of the present embodiment, it is preferable that at least one ^{of OR 1} and OR ^{3 of the compound represented by the formula (a) has a branched structure.}

The branched conjugated diene-based polymer of the present embodiment is a conjugated diene-based polymer having an active terminal having an active terminal having a branched structure obtained through a branching step from the viewpoint of fuel economy saving performance, workability, and abrasion resistance balance, and the formula (a) The reaction product of the compound represented is mentioned as a preferable form.

In general, a modified conjugated diene polymer having a branched structure has a branching point derived from a coupling agent or a modifier, and as the branching index increases, the reactivity with silica decreases when a rubber composition is constituted. In addition, in the case of a polymer having a low degree of branching, as the content and molecular weight of the coupling agent or modifier increase, the viscosity of the blend increases and the workability tends to deteriorate. Therefore, it is difficult to improve the balance between fuel economy performance and workability and wear resistance.

On the other hand, the preferred form of the branched conjugated diene-based polymer of the present embodiment is a conjugated diene-based polymer in which ^{at least one of OR 1} and OR ³ of the compound represented by the formula (a) has a branched structure. , by alleviating steric hindrance around the modifier, the branching index and molecular weight can be improved without impairing the reactivity between the branched conjugated diene-based polymer and silica.

^{Therefore, it is preferable that the modified conjugated diene-based polymer in which at least one of OR 1} and OR ³ of the compound represented by the formula (a) has a branched structure has an asymmetric structure, that is, centering on the coupling agent, on one side It is preferable that a skeleton having a branched main chain structure and a skeleton in which main chain branches are not introduced are formed on the opposite side, and the branching point of the conjugated diene polymer obtained through the branching step and the branching point formed by the modifier are molecular weight It is more preferable that it isolate|separated by 10,000 or more molecular chains.

<Polymerization terminator process>

In the production method of the branched conjugated diene-based polymer of the present embodiment, a reaction step of reacting the above-described coupling agent or polymerization terminator with the active terminal of the conjugated diene-based polymer obtained through the above-described polymerization step and branching step can be carried out.

As the polymerization termination step, for example, a polymerization termination step in which a bifunctional reactive compound is used for the active terminal of the conjugated diene-based polymer, or a polymerization terminator having a nitrogen atom-containing group (hereinafter collectively referred to as “polymerization terminator”). It may be described.), the polymerization termination step is preferred.

In the polymerization termination step, for example, the active terminal of the polymer obtained in the above-described branching step is subjected to a polymerization termination reaction with a bifunctional reactive compound or a polymerization terminator having a nitrogen atom-containing group, and a target branching conjugate is used. A diene-based polymer can be obtained.

[Bifunctional Reactive Compound]

In the method for producing the branched conjugated diene-based polymer of the present embodiment, the bifunctional reactive compound used in the polymerization terminating step may have any structure, but is preferably a bifunctional reactive compound having a silicon atom. desirable.

[Polymerization terminator having a nitrogen atom-containing group]

In the method for producing the branched conjugated diene-based polymer of the present embodiment, the polymerization terminator having a nitrogen atom-containing group used in the polymerization termination step may have any structure, but preferably a functional group that reacts with the conjugated diene-based polymer. It is preferable to have

As the polymerization terminator having a nitrogen atom-containing group, an alkoxy compound having a nitrogen atom-containing group is preferable from the viewpoint of improving fuel economy performance.

Examples of the polymerization terminator having a nitrogen atom-containing group include 3-(N,N-dimethylaminopropyl)dimethoxymethylsilane, 3-(N,N-diethylaminopropyl)dimethoxymethylsilane, 3-(N ,N-dipropylaminopropyl)dimethoxymethylsilane, 3-(N,N-dimethylaminopropyl)diethoxymethylsilane, 3-(N,N-diethylaminopropyl)diethoxymethylsilane, 3-(N ,N-dipropylaminopropyl)diethoxymethylsilane, 3-(N,N-dimethylaminopropyl)dimethoxyethylsilane, 3-(N,N-diethylaminopropyl)dimethoxyethylsilane, 3-(N ,N-dipropylaminopropyl)dimethoxyethylsilane, 3-(N,N-dimethylaminopropyl)diethoxyethylsilane, 3-(N,N-diethylaminopropyl)diethoxyethylsilane, 3-(N ,N-dipropylaminopropyl)diethoxyethylsilane, etc. are mentioned.

The branched structure of the branched conjugated diene-based polymer obtained through the polymerization step, branching step and reaction step described above by the production method of the present embodiment is more preferably 6 branches or more and 36 branches or less, 8 branches or more and 36 branches or less. It is preferably branched or less, more preferably 8 branches or more and 24 branches or less, 10 branches or more and 24 branches or less, 10 branches or more and 22 branches or less, and more preferably 12 branches or more and 20 branches or less.

Two or more places are preferable, as for the total number of branch points in the branched conjugated diene polymer obtained by the manufacturing method of this embodiment, 3 or more places are more preferable, 4 or more places are still more preferable, 5 or more places are especially more preferably.

If the branch structure and the total number of branching points are within the above-mentioned ranges, there is a tendency for excellent workability, fuel economy, and abrasion resistance.

In order to construct a branched conjugated diene-based polymer having a branching structure of 8 to 36 branches, and in the case of a modified polymer, the total number of branching points is 2 or more and 15 or less, the molar ratio of the branching agent is 2 minutes of the polymerization initiator. It is 1 or less and 1/100 or more, and it is necessary to use 3 or more functional groups in the number of functional groups of the coupling agent. In the case of a polymer which does not require modification, one or more branch points may be sufficient.

In order to construct a branching structure having 8 or more branches and 36 or less branches and the total number of branching points is 3 or more and 12 or less, the molar ratio of the branching agent is 1/3 or less of the polymerization initiator and 1/50 or more, and the coupling agent It is preferable to use the functional group number of tetrafunctional or more.

In order to establish a branching structure of 10 or more and 24 or less branches, and the total number of branching points is 4 or more and 10 or less, the molar ratio of the branching agent is 1/6 or less of the polymerization initiator and 1/25 or more, and the coupling agent It is preferable to use a functional group number of 5 or more.

In order to construct a branching structure having 12 or more branches and 20 or less branches and the total number of branching points is 5 or more and 9 or less, the molar ratio of the branching agent is 1/8 or less and 1/12 or more of the polymerization initiator, and the coupling agent It is preferable to use a functional group number of 6 or more.

(Condensation reaction process)

In the manufacturing method of the branched conjugated diene polymer of this embodiment, you may perform the condensation reaction process of carrying out a condensation reaction in presence of a condensation accelerator after the above-mentioned coupling process or before a coupling process.

(hydrogenation process)

In the manufacturing method of the branched conjugated diene type polymer of this embodiment, you may implement the hydrogenation process of hydrogenating the conjugated diene part.

The method of hydrogenating the conjugated diene part of a conjugated diene type polymer is not specifically limited, A well-known method can be used.

As a suitable hydrogenation method, the method of hydrogenation by the method of blowing gaseous hydrogen into a polymer solution in presence of a catalyst is mentioned. Although it does not specifically limit as a catalyst, For example, Heterogeneous catalysts, such as a catalyst which supported the noble metal on the porous inorganic substance; Homogeneous catalysts, such as a catalyst made to solubilize salts, such as nickel and cobalt, and reacted with organoaluminum etc., and a catalyst using metallocenes, such as titanocene, are mentioned. Among these, a titanocene catalyst is preferable from a viewpoint of being able to select mild hydrogenation conditions. In addition, hydrogenation of an aromatic group can be performed by using the supported catalyst of a noble metal.

Examples of the hydrogenation catalyst include, but are not limited to, (1) a supported heterogeneous hydrogenation catalyst in which a metal such as Ni, Pt, Pd, and Ru is supported on carbon, silica, alumina, diatomaceous earth, or the like, (2) Ni , a so-called Ziegler type hydrogenation catalyst using an organic acid salt such as Co, Fe, Cr, or a transition metal salt such as an acetylacetone salt and a reducing agent such as organoaluminum; (3) an organometallic compound such as Ti, Ru, Rh, Zr So-called organometallic complexes, such as these, etc. are mentioned. Moreover, although it does not specifically limit as a hydrogenation catalyst, For example, Japanese Patent Publication No. 42-8704, Japanese Patent Publication No. 43-6636, Japanese Patent Publication No. 63-4841, Japanese Patent Publication Hei 1- The well-known hydrogenation catalysts described in Unexamined-Japanese-Patent No. 37970, Unexamined-Japanese-Patent No. 1-53851, Unexamined-Japanese-Patent No. 2-9041, and Unexamined-Japanese-Patent No. 8-109219 are also mentioned. As a preferable hydrogenation catalyst, the reaction mixture of a titanocene compound and a reducing organometallic compound is mentioned.

(addition process of deactivator and neutralizing agent)

In the manufacturing method of the branched conjugated diene polymer of this embodiment, you may add a deactivator, a neutralizing agent, etc. to a polymer solution after the above-mentioned coupling process as needed.

Although it does not restrict to the following as a deactivator, For example, Water; Alcohol, such as methanol, ethanol, and isopropanol, etc. are mentioned.

Examples of the neutralizing agent include, but are not limited to, carboxylic acids such as stearic acid, oleic acid, and versatic acid (a carboxylic acid mixture having 9 to 11 carbon atoms and having 10 carbon atoms and having many branches); The aqueous solution of an inorganic acid and carbon dioxide gas are mentioned.

(Addition process of stabilizer for rubber)

In the method for producing the branched conjugated diene-based polymer of the present embodiment, it is preferable to add a stabilizer for rubber from the viewpoint of preventing gel formation after polymerization and improving stability during processing.

As a stabilizer for rubber, it is not limited to the following, Although a well-known thing can be used, For example, 2, 6- di-tert- butyl-4-hydroxytoluene (it is also described as "BHT" hereafter), n- Antioxidants such as octadecyl-3-(4'-hydroxy-3',5'-di-tert-butylphenol)propinate and 2-methyl-4,6-bis[(octylthio)methyl]phenol desirable.

(Addition process of softener for rubber)

In the method for producing the branched conjugated diene-based polymer of the present embodiment, from the viewpoint of further improving the productivity of the branched conjugated diene-based polymer and processability when a resin composition is prepared by blending a filler, etc., if necessary, A soft softener may be added.

Although it does not specifically limit as a softener for rubber, For example, extender oil, liquid rubber, resin etc. are mentioned.

The method for adding the rubber softener to the branched conjugated diene polymer is not limited to the following, but the rubber softener is added to the branched conjugated diene polymer solution and mixed to obtain a polymer solution containing the rubber softener. A method of desolvation is preferred.

Preferred extender oils include, for example, aroma oil, naphthenic oil, and paraffin oil. Among these, the aromatic replacement oil whose polycyclic aromatic (PCA) component by IP346 method is 3 mass % or less is preferable from a viewpoint of environmental safety, and oil bleed prevention and a viewpoint of a wet grip characteristic. As an aroma substitute oil, in addition to TDAE (Treated Distillate Aromatic Extracts), MES (Mild Extraction Solvate), etc. shown in Kautschuk Gummi Kunststoffe 52 (12) 799 (1999), RAE (Residual Aromatic Extracts) is mentioned.

Although it is not limited to the following as a preferable liquid rubber, For example, liquid polybutadiene, liquid, styrene-butadiene rubber, etc. are mentioned.

As an effect of adding liquid rubber, in addition to being able to improve workability when a resin composition containing a branched conjugated diene polymer and a filler, etc. is prepared, the glass transition temperature of the resin composition can be shifted to the low temperature side. As a result, there is a tendency that the abrasion resistance, low hysteresis loss, and low-temperature characteristics in the case of a vulcanized product can be improved.

Examples of the resin as the rubber softener include, but are not limited to, aromatic petroleum resins, coumarone-indene resins, terpene-based resins, rosin derivatives (including tung oil resin), tall oil, derivatives of tall oil, and rosin esters. Resins, natural and synthetic terpene resins, aliphatic hydrocarbon resins, aromatic hydrocarbon resins, mixed aliphatic-aromatic hydrocarbon resins, coumarin-indene resins, phenolic resins, p-tert-butylphenol-acetylene resins, phenol-formaldehyde resins, xylene- Formaldehyde resin, monoolefin oligomer, diolefin oligomer, aromatic hydrocarbon resin, aromatic petroleum resin, hydrogenated aromatic hydrocarbon resin, cyclic aliphatic hydrocarbon resin, hydrogenated hydrocarbon resin, hydrocarbon resin, hydrogenated copper oil resin, hydrogenated oil resin, hydrogenated oil Ester of resin and monofunctional or polyfunctional alcohol, etc. are mentioned. These resins may be used by 1 type, and may use 2 or more types together. When hydrogenating, all unsaturated groups may be hydrogenated and some may remain.

As an effect of adding a resin as a softener for rubber, in addition to being able to improve workability when a resin composition containing a branched conjugated diene-based polymer and a filler, etc. is prepared, the breaking strength in the case of a vulcanized product is increased. The thing which exists in the tendency which can be improved, and the thing which can improve the wet skid resistance by being able to shift the glass transition temperature of a resin composition to a high temperature side is mentioned.

As the rubber softener, the amount of extender oil, liquid rubber, or resin to be added is not particularly limited, but is preferably 1 part by mass or more with respect to 100 parts by mass of the branched conjugated diene-based polymer obtained by the production method of the present embodiment. 60 mass parts or less, More preferably, they are 5 mass parts or more and 50 mass parts or less, More preferably, they are 10 mass parts or more and 37.5 mass parts or less.

When the rubber softener is added within the above range, the workability when a resin composition obtained by blending the branched conjugated diene-based polymer obtained by the production method of the present embodiment and a filler, etc. is improved, and when a vulcanized product Breaking strength and abrasion resistance tend to be good.

(Desolvation process)

In the manufacturing method of the branched conjugated diene type polymer of this embodiment, a well-known method can be used as a method of acquiring the obtained branched conjugated diene type polymer from a polymer solution. Although it does not specifically limit as the method, For example, after isolating a solvent by steam stripping etc., the polymer is separated by filtration, and also a method of dehydrating and drying it to obtain a polymer, a method of concentrating in a flushing tank, and furthermore, a vent extruder, etc. The method of devolatilization with a devolatilization method, the method of devolatilization directly with a drum dryer, etc. are mentioned.

[Rubber composition and manufacturing method of rubber composition]

The rubber composition of this embodiment contains 5.0 mass parts or more with respect to the rubber component containing 10 mass % or more of the branched conjugated diene-type polymer manufactured by the manufacturing method of this embodiment mentioned above, and 100 mass parts of said rubber components. 150 mass parts or less of filler is contained.

The manufacturing method of the rubber composition of this embodiment includes the process of obtaining a branched conjugated diene polymer by the manufacturing method mentioned above, the process of obtaining the rubber component containing 10 mass % or more of the said branched conjugated diene polymer, The said The process of containing 5.0 mass parts or more and 150 mass parts or less of a filler with respect to 100 mass parts of rubber components is included.

Moreover, 10 mass % of the branched conjugated diene-type polymer obtained by the manufacturing method of this embodiment is included in the said rubber component, from a viewpoint of fuel economy saving performance, workability, and abrasion resistance improvement.

It is preferable that a filler contains a silica-type inorganic filler.

The rubber composition, by dispersing the silica-based inorganic filler as a filler, tends to be more excellent in workability when used as a vulcanized product, and has a balance of abrasion resistance, breaking strength and low hysteresis loss and wet skid resistance in the case of a vulcanized product. tends to be better.

Even when the rubber composition is used for automobile parts such as tires and anti-vibration rubber, and vulcanized rubber such as shoes, it is preferable to include a silica-based inorganic filler.

The rubber composition of this embodiment is obtained by mixing the rubber component containing 10 mass % or more of the branched conjugated diene type polymer obtained by the manufacturing method mentioned above with the said filler.

The rubber component may contain rubbery polymers other than the branched conjugated diene-based polymers (hereinafter, simply referred to as “rubber-like polymers”).

Although not limited to the following as such a rubbery polymer, For example, a conjugated diene type polymer or its hydrogenated substance, a random copolymer of a conjugated diene type compound and a vinyl aromatic compound, or its hydrogenated substance, a conjugated diene type compound, and a vinyl aromatic compound of block copolymers or hydrogenated substances thereof, and other examples include non-diene polymers and natural rubbers.

The rubbery polymer is not limited to the following, but for example, butadiene rubber or its hydrogenated product, isoprene rubber or its hydrogenated product, styrene-butadiene rubber or its hydrogenated product, styrene-butadiene block copolymer or its hydrogenated product, styrene -Styrenic elastomer, such as an isoprene block copolymer or its hydrogenated substance, acrylonitrile-butadiene rubber, or its hydrogenated substance is mentioned.

Examples of the non-diene polymer include, but are not limited to, ethylene-propylene rubber, ethylene-propylene-diene rubber, ethylene-butene-diene rubber, ethylene-butene rubber, ethylene-hexene rubber, ethylene-octene rubber, and the like. of olefinic elastomers, butyl rubber, brominated butyl rubber, acrylic rubber, fluororubber, silicone rubber, chlorinated polyethylene rubber, epichlorohydrin rubber, α,β-unsaturated nitrile-acrylic acid ester-conjugated diene copolymer rubber, urethane rubber and and sulfurized rubber.

Although it does not restrict to the following as a natural rubber, For example, RSS3-5 which are smoke sheets, SMR, and an epoxidized natural rubber are mentioned.

The various rubbery polymers mentioned above may be modified rubbers to which a functional group having a polarity, such as a hydroxyl group or an amino group, is provided. When used for tires, butadiene rubber, isoprene rubber, styrene-butadiene rubber, natural rubber and butyl rubber are preferably used.

It is preferable that they are 2000 or more and 2000000 or less, and, as for the weight average molecular weight of a rubber-like polymer, it is more preferable that they are 5000 or more and 1500000 or less from a viewpoint of the balance of the various performance of a resin composition, and processing characteristic. It is also possible to use a low molecular weight rubbery polymer, so-called liquid rubber.

These rubbery polymers may be used individually by 1 type, and may use 2 or more types together.

In the case where the rubber composition using the branched conjugated diene-based polymer obtained by the production method of the present embodiment is a rubber composition containing the above-mentioned rubbery polymer, the above-mentioned branched conjugated diene-based polymer with respect to the rubbery polymer The content ratio (mass ratio) is (above-mentioned branched conjugated diene polymer/rubber polymer), preferably 10/90 or more and 100/0 or less, more preferably 20/80 or more and 90/10 or less, and 50/ 50 or more and 80/20 or less are more preferable.

Therefore, the rubber component preferably contains 10% by mass or more and 100% by mass or less of the branched conjugated diene-based polymer described above with respect to the total amount (100% by mass) of the rubber component, more preferably 20% by mass. 90 mass % or more is included, More preferably, 50 mass % or more and 80 mass % or less are included.

If the content ratio of (branched conjugated diene-based polymer/rubber polymer) is within the above range, the vulcanized product has excellent abrasion resistance and fracture strength, and the balance between low hysteresis loss and wet skid resistance tends to be good. have.

Although it is not limited to the following as a filler contained in a rubber composition, For example, carbon black, a metal oxide, and a metal hydroxide other than the said silica-type inorganic filler are mentioned. Among these, silica-based inorganic fillers are preferable.

A filler may be used individually by 1 type, and may use 2 or more types together.

Content of the filler in a rubber composition is 5.0 mass parts or more and 150 mass parts with respect to 100 mass parts of rubber components containing the above-mentioned branched conjugated diene polymer, 20 mass parts or more and 100 mass parts or less are preferable, 30 mass parts A part or more and 90 mass parts or less are more preferable.

In the rubber composition, the content of the filler is 5.0 parts by mass or more with respect to 100 parts by mass of the rubber component from the viewpoint of exhibiting the effect of adding the filler, the filler is sufficiently dispersed, and the processability and mechanical strength of the rubber composition are practically sufficient. It is 150 mass parts or less with respect to 100 mass parts of rubber components from a viewpoint of setting it as a thing.

The silica-based inorganic filler is not particularly limited, and a known one can be used, but _{solid particles containing SiO 2} or Si ₃ Al as a structural unit are preferable, and SiO ₂ or Si ₃ Al as a main component of the structural unit. Solid particles are more preferable. Here, a main component is 50 mass % or more in a silica-type inorganic filler, Preferably it is 70 mass % or more, More preferably, 80 mass % or more means the component contained.

Examples of the silica-based inorganic filler include, but are not limited to, inorganic fibrous substances such as silica, clay, talc, mica, diatomaceous earth, wollastonite, montmorillonite, zeolite, and glass fiber. Moreover, the mixture of the silica-type inorganic filler which made the surface hydrophobic, the silica-type inorganic filler, and inorganic fillers other than the silica type is also mentioned.

Among these, from viewpoints, such as intensity|strength and abrasion resistance, a silica and glass fiber are preferable, and a silica is more preferable.

Examples of the silica include fumed silica, wet silica, and synthetic silicate silica. Among these silicas, wet silica is preferable from the viewpoint of excellent balance of the breaking strength improvement effect and wet skid resistance.

From the viewpoint of obtaining practically good abrasion resistance and breaking strength in the rubber composition, the nitrogen adsorption specific surface area obtained by the BET adsorption method of the silica-based inorganic filler is preferably 100 m 2 /g or more and 300 m 2 /g or less, and 170 m 2 /g It is more preferable that it is more than 250 m<2>/g.

In addition, if necessary, a silica-based inorganic filler having a relatively small specific surface area (eg, less than 200 m 2 /g) and a silica-based inorganic filler having a relatively large specific surface area (eg, 200 m 2 /g or more) can be used in combination.

In particular, in the case of using a silica-based inorganic filler with a relatively large specific surface area (for example, 200 m 2 /g or more), the rubber composition comprising the above-described branched conjugated diene-based polymer improves the dispersibility of silica, In particular, it is effective in improving wear resistance, and tends to be able to highly balance good breaking strength and low hysteresis loss properties.

As for content of the silica-type inorganic filler in a rubber composition, 5.0 mass parts or more and 150 mass parts are preferable with respect to 100 mass parts of rubber components containing the branched conjugated diene-type polymer obtained by the manufacturing method of this embodiment, 20 mass parts More than 100 parts by mass or less is more preferable. In the rubber composition, the content of the silica-based inorganic filler is preferably 5.0 parts by mass or more with respect to 100 parts by mass of the rubber component from the viewpoint of exhibiting the effect of adding the silica-based inorganic filler, and the silica-based inorganic filler is sufficiently dispersed. , 150 parts by mass or less is preferable with respect to 100 parts by mass of the rubber component from the viewpoint of making the workability and mechanical strength of the rubber composition practically sufficient.

Examples of carbon black include, but are not limited to, carbon black of each class such as SRF, FEF, HAF, ISAF, and SAF. Among these, carbon black having a nitrogen adsorption specific surface area of 50 m 2 /g or more and a dibutyl phthalate (DBP) oil absorption of 80 mL/100 g or less is preferable.

In the rubber composition, the content of carbon black is preferably 0.5 parts by mass or more and 100 parts by mass or less with respect to 100 parts by mass of the rubber component containing the branched conjugated diene-based polymer obtained by the production method of the present embodiment, and 3.0 100 mass parts or less are more preferable, and 5.0 mass parts or more and 50 mass parts or less are still more preferable. In the rubber composition, the content of carbon black is preferably 0.5 parts by mass or more with respect to 100 parts by mass of the rubber component from the viewpoint of expressing the performance required for applications such as tires, such as dry grip performance and conductivity, and dispersed It is preferable to set it as 100 mass parts or less with respect to 100 mass parts of rubber components from a viewpoint of property.

The metal oxide refers to solid particles having the chemical formula MxOy (M represents a metal atom, and x and y each independently represent an integer of 1 to 6) as a main component of a structural unit.

Although it is not limited to the following as a metal oxide, For example, alumina, titanium oxide, magnesium oxide, and zinc oxide are mentioned.

Although it is not limited to the following as a metal hydroxide, For example, aluminum hydroxide, magnesium hydroxide, and zirconium hydroxide are mentioned.

In the manufacturing method of the rubber composition of this embodiment, you may make it contain a silane coupling agent.

The silane coupling agent has a function of intimately interacting between the rubber component and the inorganic filler, has an affinity or binding group for each of the rubber component and the silica-based inorganic filler, and has a sulfur bonding moiety and an alkoxysilyl group or A compound having a silanol group moiety in one molecule is preferable. Although it does not specifically limit as such a compound, For example, bis-[3-(triethoxysilyl)-propyl]-tetrasulfide, bis-[3-(triethoxysilyl)-propyl]-disulfide, bis -[2-(triethoxysilyl)-ethyl]-tetrasulfide is mentioned.

In the rubber composition, the content of the silane coupling agent is preferably 0.1 parts by mass or more and 30 parts by mass or less, more preferably 0.5 parts by mass or more and 20 parts by mass or less, and 1.0 parts by mass with respect to 100 parts by mass of the above-mentioned inorganic filler. More than 15 parts by mass or less is more preferable. There exists a tendency which can make the said addition effect by a silane coupling agent into a more remarkable thing that content of a silane coupling agent is the said range.

A rubber composition may also contain the softening agent for rubber|gum from a viewpoint of aiming at the improvement of the processability.

The amount of the softener for rubber added is to 100 parts by mass of the rubber component containing the branched conjugated diene polymer obtained by the production method of the present embodiment described above, to the branched conjugated diene polymer or other rubbery polymer described above. It is expressed by the amount including the softener for rubber contained and the total amount of the softener for rubber added when preparing the rubber composition.

As the softener for rubber, mineral oil or a liquid or low molecular weight synthetic softener is suitable.

A softener for mineral oil-based rubber called process oil or extender oil, which is used for softening, thickening, and improving processability of rubber, is a mixture of aromatic rings, naphthenic rings and paraffin chains, and the number of carbon atoms in the paraffin chain is out of the total carbon. What occupies 50% or more is called a paraffinic system, what occupies 30% or more and 45% or less of the total carbon is called a naphthenic system, and what occupies more than 30% of the total carbon is called an aromatic system. When the conjugated diene-based polymer of the present embodiment is a copolymer of a conjugated diene compound and a vinyl aromatic compound, the rubber softener to be used is preferably one having an appropriate aromatic content because affinity with the copolymer tends to be good.

In the rubber composition, the content of the softener for rubber is preferably 0 parts by mass or more and 100 parts by mass or less, more preferably 10 parts by mass or more and 90 parts by mass or less, 30 parts by mass or more and 90 parts by mass relative to 100 parts by mass of the rubber component. Parts by mass or less are more preferable. When content of the softener for rubber is 100 mass parts or less with respect to 100 mass parts of rubber components, it exists in the tendency for bleed-out to be suppressed and to suppress the stickiness of the rubber composition surface.

About the method of mixing the branched conjugated diene-based polymer obtained by the production method of the present embodiment with other rubbery polymers, silica-based inorganic fillers, carbon black or other fillers, silane coupling agents, rubber softeners, etc. , Although not limited to the following, for example, a melt-kneading method using a general mixer such as an open roll, a Banbury mixer, a kneader, a single screw extruder, a twin screw extruder, and a multi screw extruder, after dissolving and mixing each component, the solvent The method of heating and removing is mentioned.

Among these, the melt-kneading method by a roll, a Banbury mixer, a kneader, and an extruder is preferable from a viewpoint of productivity and favorable kneading|mixing property. In addition, a method of kneading a rubber component and other fillers, a silane coupling agent, and an additive at once, and a method of mixing the rubber component with a plurality of times are applicable.

The rubber composition may be a vulcanized composition that has been vulcanized with a vulcanizing agent. Examples of the vulcanizing agent include, but are not limited to, radical generators such as organic peroxides and azo compounds, oxime compounds, nitroso compounds, polyamine compounds, sulfur, and sulfur compounds. The sulfur compounds include sulfur monochloride, sulfur dichloride, disulfide compounds, high molecular weight polysulfur compounds, and the like.

Rubber composition WHEREIN: 0.01 mass part or more and 20 mass parts or less are preferable with respect to 100 mass parts of rubber components, and, as for content of a vulcanizing agent, 0.1 mass part or more and 15 mass parts or less are more preferable. As the vulcanization method, a conventionally known method can be applied, and the vulcanization temperature is preferably 120°C or more and 200°C or less, and more preferably 140°C or more and 180°C or less.

In the case of vulcanization, you may use a vulcanization accelerator as needed. As the vulcanization accelerator, a conventionally known material can be used, and although it is not limited to the following, for example, a sulfenamide-based, guanidine-based, thiuram-based, aldehyde-amine-based, aldehyde-ammonia-based, thiazole-based, thiourea-based agent and dithiocarbamate-based vulcanization accelerators. Moreover, as a vulcanization adjuvant, Although it is although it does not restrict to the following, For example, zinc oxide and stearic acid are mentioned. 0.01 mass part or more and 20 mass parts or less are preferable with respect to 100 mass parts of rubber components, and, as for content of a vulcanization accelerator, 0.1 mass part or more and 15 mass parts or less are more preferable.

Various additives such as softeners and fillers other than those described above, heat-resistant stabilizers, antistatic agents, weather-resistance stabilizers, anti-aging agents, colorants, lubricants, etc. may be used in the rubber composition within the scope not impairing the purpose of the present embodiment. do.

As other softeners, a well-known softening agent can be used.

Although it does not specifically limit as another filler, For example, calcium carbonate, magnesium carbonate, aluminum sulfate, and barium sulfate are mentioned. As the above-described heat-resistant stabilizer, antistatic agent, weather-resistant stabilizer, anti-aging agent, colorant, and lubricant, each known material can be used.

[Tire and tire manufacturing method]

The tire of this embodiment contains the rubber composition of this embodiment mentioned above.

The manufacturing method of the tire of this embodiment comprises the process of obtaining a branched conjugated diene polymer by the manufacturing method of this embodiment, the process of obtaining the rubber composition containing the said branched conjugated diene polymer, The said rubber composition It has a shaping|molding process.

The rubber composition containing the branched conjugated diene polymer obtained by the manufacturing method of this embodiment mentioned above is used suitably as a rubber composition for tires.

The rubber composition for a tire is not limited to the following, but for example, various tires such as fuel economy tires, all-season tires, high performance tires, and studless tires: Tire parts such as tread, carcass, sidewall, bead, etc. is available for use. In particular, the rubber composition for tires has excellent balance of abrasion resistance, breaking strength, low hysteresis loss, and wet skid resistance when used as a vulcanized product, and therefore is suitably used as a tread for fuel economy tires and high-performance tires.

[Example]

Hereinafter, although a specific Example and a comparative example are given and this embodiment is demonstrated in more detail, this embodiment is not limited at all by the following Example and a comparative example.

[First embodiment]

Hereinafter, various physical properties in Examples and Comparative Examples of [Example 1] were measured by the methods shown below.

In the following, the conjugated diene-based polymer coupled with the nitrogen atom-containing modifier is described as a “coupling conjugated diene-based polymer”.

In addition, the conjugated diene-type polymer of an unmodified state is described as "unmodified conjugated diene-type polymer."

In addition, the conjugated diene-type polymer which has a branched structure is described as "branched conjugated diene-type polymer."

(Physical Properties 1) Polymer Mooney Viscosity

Using an unmodified conjugated diene-based polymer or a conjugated diene-based polymer coupled with a nitrogen atom-containing modifier (hereinafter also referred to as “coupling conjugated diene-based polymer”) as a sample, a Mooney viscometer (manufactured by Uejima Seisakusho Co., Ltd.) was used as a sample. Based on ISO 289 using the brand name "VR ¹ 132"), the Mooney viscosity was measured using the L-type rotor.

The measurement temperature was made into 110 degreeC when making an unmodified conjugated diene-type polymer into a sample, and made into 100 degreeC when using a coupling conjugated diene-type polymer as a sample.

First, after preheating a sample at the test temperature for 1 minute, the rotor was rotated at 2 rpm, the torque after 4 minutes was measured, and it was set as Mooney viscosity (ML ₍₁₊₄₎ ).

(Physical property 2) Mooney relaxation rate

After using a coupling conjugated diene polymer as a sample and using a Mooney viscometer (trade name "VR ¹ 132" manufactured by Uejima Seisakusho Co., Ltd.), according to ISO 289, using an L-type rotor to measure the Mooney viscosity , immediately stop the rotation of the rotor, record the torque every 0.1 seconds for 1.6 seconds to 5 seconds after stopping, in Mooney units, find the slope of the straight line when the torque and time (seconds) are plotted as positive logarithms, and the absolute value This is called the Mooney relaxation rate (MSR).

(Physical property 3) Branching degree (Bn)

The degree of branching (Bn) of the coupling conjugated diene polymer was measured as follows by a GPC-light scattering method having a viscosity detector.

Light scattering using a gel permeation chromatography (GPC) measuring apparatus (trade name "GPCmax VE-2001" manufactured by Malvern) in which three columns using a coupling conjugated diene-based polymer as a sample and polystyrene-based gel as a filler were connected A detector, an RI detector, and a viscosity detector (trade name "TDA305" manufactured by Malvern) were used for measurement using three detectors connected in this order, and based on standard polystyrene, the absolute molecular weight was determined from the results of the light scattering detector and the RI detector, RI The intrinsic viscosity was calculated|required from the result of a detector and a viscosity detector.

A linear polymer, the intrinsic viscosity [η] = - use as according to 3.883M ^0.771, the shrinkage factor was calculated (g ') as the intrinsic viscosity ratio corresponding to the molecular weight. In addition, in formula, M represents an absolute molecular weight.

Then, the degree of branching (Bn) defined as g'=6Bn/{(Bn+1)(Bn+2)} was calculated using the obtained shrinkage factor g'.

As the eluent, 5 mmol/L of triethylamine-containing tetrahydrofuran (hereinafter also referred to as “THF”) was used.

The column was used by connecting the brand names "TSKgel G4000HXL", "TSKgel G5000HXL" and "TSKgel G6000HXL" manufactured by Tosoh Corporation.

20 mg of the sample for measurement was dissolved in 10 mL of THF to prepare a measurement solution, 100 µL of the measurement solution was poured into a GPC measuring apparatus, and the measurement was performed under the conditions of an oven temperature of 40°C and a THF flow rate of 1 mL/min.

(Physical Properties 4) Molecular Weight

<Measurement condition 1>:

Using an unmodified conjugated diene-based polymer or a coupling conjugated diene-based polymer as a sample, and a GPC measuring device (trade name "HLC-8320GPC" manufactured by Tosoh Corporation) in which three columns using polystyrene gel as a filler are connected, The chromatogram was measured using an RI detector (trade name "HLC8020" manufactured by Tosoh Corporation), and based on a calibration curve obtained using standard polystyrene, the weight average molecular weight (Mw), the number average molecular weight (Mn), and the molecular weight distribution (Mw/ Mn) was found.

As the eluent, 5 mmol/L of triethylamine-containing THF (tetrahydrofuran) was used. The column was used by connecting three trade names "TSKgel SuperMultiporeHZ-H" manufactured by Tosoh Corporation, and connecting the trade name "TSKguardcolumn SuperMP(HZ)-H" manufactured by Tosoh Corporation to the preceding stage as a guard column.

10 mg of the sample for measurement was dissolved in 10 mL of THF to obtain a measurement solution, 10 µL of the measurement solution was poured into a GPC measuring apparatus, and the measurement was performed under the conditions of an oven temperature of 40°C and a THF flow rate of 0.35 mL/min.

Among the various samples measured under the measurement condition 1 described above, the sample having a molecular weight distribution (Mw/Mn) of less than 1.6 was further measured under the measurement condition 2 below. It was measured on the measurement condition 1, and about the sample whose molecular weight distribution value was 1.6 or more, the measurement value measured by the measurement condition 1 was employ|adopted.

<Measurement condition 2>:

Using an unmodified conjugated diene-based polymer or a coupling conjugated diene-based polymer as a sample, the chromatogram was measured using a GPC measuring device in which three columns using polystyrene gel as a filler were connected, and a calibration curve using standard polystyrene Based on this, the weight average molecular weight (Mw) and the number average molecular weight (Mn) were calculated|required.

As the eluent, 5 mmol/L of triethylamine-containing THF was used. As the column, guard column: Tosoh Corporation brand name "TSKguardcolumn SuperH-H", Column: Tosoh Corporation brand name "TSKgel SuperH5000", "TSKgel SuperH6000", and "TSKgel SuperH7000" were used.

An RI detector (trade name "HLC8020" manufactured by Tosoh Corporation) was used under the conditions of an oven temperature of 40°C and a THF flow rate of 0.6 mL/min. 10 mg of the sample for a measurement was melt|dissolved in 20 mL of THF, it was set as the measurement solution, 20 microliters of the measurement solutions were poured into the GPC measuring apparatus, and it measured.

It measured on the measurement condition 1, and about the sample whose molecular weight distribution value was less than 1.6, it measured on the measurement condition 2.

(physical property 5) rate of denaturation

The rate of modification of the coupling conjugated diene polymer was measured by column adsorption GPC method as follows.

It was measured by applying the characteristic which the modified|denatured basic polymer component adsorb|sucks to the GPC column which used a coupling conjugated diene type polymer as a sample and used silica gel as a filler.

The amount of adsorption to the silica column was measured from the difference between the chromatogram measured by the polystyrene column and the chromatogram measured by the silica column for the sample solution and the sample solution containing the low molecular weight internal standard polystyrene to determine the denaturation rate. .

Specifically, it is as showing below.

In addition, it measured on the measurement condition 1 of the above-mentioned (physical property 4), and about the sample whose molecular weight distribution value was 1.6 or more, it measured on the measurement condition 3 below. It was measured under the measurement condition 1 of the said (physical property 4), and about the sample whose molecular weight distribution value was less than 1.6, it measured under the measurement condition 4 below.

<Preparation of sample solution>:

10 mg of the sample and 5 mg of standard polystyrene were dissolved in 20 mL of THF to prepare a sample solution.

<Measurement condition 3>:

GPC measurement conditions using a polystyrene-based column:

Using the trade name "HLC-8320GPC" manufactured by Tosoh Corporation, using 5 mmol/L of triethylamine-containing THF as the eluent, 10 μL of the sample solution was injected into the device, and the column oven temperature was 40° C., and the THF flow rate was 0.35 mL/min. Under the conditions, chromatograms were obtained using an RI detector.

The column was used by connecting three trade names "TSKgel SuperMultiporeHZ-H" manufactured by Tosoh Corporation, and connecting the trade name "TSKguardcolumn SuperMP(HZ)-H" manufactured by Tosoh Corporation to the preceding stage as a guard column.

<Measurement condition 4>:

THF containing 5 mmol/L of triethylamine was used as the eluent, and 20 μL of the sample solution was injected into the device for measurement.

As the column, guard column: Tosoh Corporation brand name "TSKguardcolumn SuperH-H", Column: Tosoh Corporation brand name "TSKgel SuperH5000", "TSKgel SuperH6000", and "TSKgel SuperH7000" were used. It measured using the RI detector (HLC8020 by Tosoh Corporation) on the conditions of the column oven temperature of 40 degreeC and the THF flow volume of 0.6 mL/min, and obtained the chromatogram.

GPC measurement conditions using a silica-based column: Using the trade name "HLC-8320GPC" manufactured by Tosoh Corporation, using THF as the eluent, 50 µL of the sample solution was injected into the apparatus, the column oven temperature was 40°C, and the THF flow rate was 0.5 ml/min. Under the conditions of , a chromatogram was obtained using an RI detector. The column was used by connecting trade names "Zorbax PSM-1000S", "PSM-300S", and "PSM-60S", and connecting and using the trade name "DIOL 4.6 x 12.5 mm 5micron" as a guard column in the preceding stage.

To calculate the rate of denaturation:

The total peak area of the chromatogram using the polystyrene column is 100, the peak area of the sample is P1, the peak area of the standard polystyrene is P2, and the total of the peak area of the chromatogram using the silica column is 100, and the sample The denaturation rate (%) was calculated|required from the following formula, making the peak area of P3 and the peak area of standard polystyrene P4.

Denaturation rate (%) = [1-(P2×P3)/(P1×P4)]×100

(However, P1+P2=P3+P4=100)

(Physical property 6) Amount of bound styrene

A coupling conjugated diene-based polymer containing no softener for rubber was used as a sample, and 100 mg of the sample was weighed up to 100 mL with chloroform and dissolved to obtain a measurement sample.

The amount (mass %) of bound styrene with respect to 100 mass % of the coupling conjugated diene polymer which is a sample was measured based on the absorption amount of the ultraviolet absorption wavelength (254 nm vicinity) by the phenyl group of styrene (measuring apparatus: Shimadzu Corporation make. of the spectrophotometer "UV-2450").

(Physical property 7) Microstructure of butadiene moiety (1,2-vinyl bond amount)

A coupling conjugated diene-based polymer containing no softener for rubber was used as a sample, and 50 mg of the sample was dissolved in 10 mL of carbon disulfide to obtain a measurement sample.

Using a solution cell, the infrared spectrum ^{was measured in the range of 600 to 1000 cm -1} , and the absorbance at a predetermined wavenumber was determined by Hampton's method (method described in RR Hampton, Analytical Chemistry 21, 923 (1949)). The microstructure of the butadiene moiety, that is, the amount of 1,2-vinyl bonds (mol%) was determined according to the formula of (Measuring device: Fourier transform infrared spectrophotometer "FT-IR230" manufactured by Nippon Bunko Corporation).

(Physical property 8) Molecular weight (absolute molecular weight) by GPC-light scattering method measurement

Using a coupling conjugated diene-based polymer as a sample and using a GPC-light scattering measuring device in which three columns with polystyrene gel as a filler are connected, the chromatogram is measured, and the weight average molecular weight is based on the solution viscosity and the light scattering method. (Mw-i) was obtained (also referred to as "absolute molecular weight").

A mixed solution of tetrahydrofuran and triethylamine (THF in TEA: 5 mL of triethylamine was mixed with 1 L of tetrahydrofuran to prepare the eluent) was used.

The column was used by connecting a guard column: "TSKguardcolumn HHR-H" manufactured by Tosoh Corporation, and a column: "TSKgel G6000HHR", "TSKgel G5000HHR", "TSKgel G4000HHR" manufactured by Tosoh Corporation.

On the conditions of an oven temperature of 40 degreeC, and THF flow volume 1.0 mL/min, the GPC-light scattering measuring apparatus (trade name "Viscotek TDAmax" manufactured by Malvern Corporation) was used.

10 mg of the sample for a measurement was melt|dissolved in 20 mL of THF, it was set as the measurement solution, 200 microliters of the measurement solutions were injected into the GPC measuring apparatus, and it measured.

[Branched Conjugated Diene-Based Polymer]

(Example 1-1) Coupling conjugated diene-based polymer (Sample 1-1)

The inner volume is 10L, the ratio (L/D) of the inner height (L) to the diameter (D) is 4.0, has an inlet at the bottom, an outlet at the top, and a stirrer, which is a tank reactor having a stirrer, and a jacket for temperature control The tank pressure vessel which had was made into a polymerization reactor, and two groups were connected.

1,3-butadiene, which had been previously dehydrated, was mixed under the conditions of 18.6 g/min, styrene at 10.0 g/min, and n-hexane at 175.2 g/min. In a static mixer provided in the middle of a pipe for supplying this mixed solution to the inlet of the reactor, n-butyllithium for inert treatment of residual impurities was added and mixed at 0.103 mmol/min, and then continuously supplied to the bottom of the reactor. In addition, 2,2-bis(2-oxolanyl)propane as a polar material at a rate of 0.081 mmol/min and n-butyllithium as a polymerization initiator at a rate of 0.143 mmol/min were vigorously mixed with a stirrer. The first stage was supplied to the bottom of the reactor, and the temperature inside the reactor was maintained at 67°C.

The polymer solution was continuously withdrawn from the top of the reactor in the first stage, continuously fed to the bottom of the reactor in the second stage to continue the reaction at 70° C., and further fed to a static mixer from the top of the second stage. In the place where polymerization is sufficiently stable, while copolymerizing 1,3-butadiene and styrene, from the bottom of the second reactor, trimethoxy(4-vinylphenyl)silane as a branching agent (in the table, "BS-1" is reduced) .) was added at a rate of 0.0190 mmol/min to conduct a polymerization reaction and branching reaction to obtain a conjugated diene-based polymer having a branched main chain structure.

In addition, in a place where the polymerization reaction and branching reaction are stable, a small amount of the conjugated diene-based polymer solution before addition of the coupling agent is extracted, and after adding the antioxidant (BHT) so that it becomes 0.2 g per 100 g of the polymer, the solvent is removed, and the Mooney viscosity and various molecular weights were measured. The physical properties are shown in Table 1.

Then, to the polymer solution flowing out from the outlet of the reactor, tetraethoxysilane (abbreviated as "A" in the table) as a coupling agent was continuously added at a rate of 0.0480 mmol/min, and mixed using a static mixer. and a coupling reaction was carried out. At this time, the time until the coupling agent is added to the polymer solution flowing out from the outlet of the reactor is 4.8 minutes, the temperature is 68°C, and the difference between the temperature in the polymerization step and the temperature until the coupling agent is added is 2 ℃ was. After the coupling reaction, a small amount of the conjugated diene-based polymer solution is extracted, an antioxidant (BHT) is added so that 0.2 g per 100 g of the polymer, and the solvent is removed, and the amount of bound styrene (physical property 6) and the microstructure of the butadiene portion (1 ,2-vinyl bond amount: Physical property 7) was measured. Table 1 shows the measurement results.

Next, to the polymer solution subjected to the coupling reaction, an antioxidant (BHT) was continuously added at a rate of 0.055 g/min (n-hexane solution) to 0.2 g per 100 g of the polymer, and the coupling reaction was terminated. Simultaneously with the antioxidant, as a softener for rubber, SRAE oil (JOMO Process NC140 manufactured by JX Nikko Niseki Energy Co., Ltd.) was continuously added to 25.0 g with respect to 100 g of the polymer, and mixed with a static mixer. The solvent is removed by steam stripping, and it has a four-branched structure derived from a branching agent (hereinafter also referred to as "branching agent structure (1)") which is a compound represented by the following formula (1) in a part of the main chain, and a coupling agent A coupling conjugated diene-based polymer (Sample 1-1) having an derived three-branched star polymer structure was obtained.

Table 1 shows the physical properties of Sample 1-1.

In addition, with respect to the polymer before the addition of the branching agent, the polymer after the addition of the branching agent, and the polymer in each step after the addition of the coupling agent, the molecular weight by GPC measurement and the degree of branching by GPC measurement with a viscometer are compared by comparison of coupling The structure of the conjugated diene-based polymer was identified. Hereinafter, the structure of each sample was similarly identified.

(In Formula (1), R<^1> represents any selected from the group which consists of a hydrogen atom, a C1-C20 alkyl group, and a C6-C20 aryl group, and may have a branched structure in the part.

X ¹ is a single bond or an organic group containing any one selected from the group consisting of carbon, hydrogen, nitrogen, sulfur and oxygen.

Y ¹ represents any selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, and a halogen atom. Each is independent and may be the same or different.)

(Example 1-2) Coupling conjugated diene-based polymer (Sample 1-2)

Example 1 except that the coupling agent was changed from tetraethoxysilane to 1,2-bis(triethoxysilyl)ethane (abbreviated as "B" in the table), and the addition amount was changed to 0.0360 mmol/min. In the same manner as -1, a coupling conjugated diene-based polymer (Sample 1-2) having a four-branched structure derived from the branching agent structure (1) in a part of the main chain and having a four-branched star polymer structure derived from the coupling agent was obtained. Table 1 shows the physical properties of Sample 1-2.

(Example 1-3) Coupling conjugated diene-based polymer (Sample 1-3)

The coupling agent was changed from tetraethoxysilane to 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane (in the table, abbreviated as "C"), and the amount added was changed to 0.0360 mmol/min. Except that, in the same manner as in Example 1-1, a coupling conjugated diene polymer having a four-branched structure derived from the branching agent structure (1) in a part of the main chain and a four-branched star polymer structure derived from the coupling agent (sample) 1-3) were obtained. Table 1 shows the physical properties of Samples 1-3.

(Example 1-4) Coupling conjugated diene-based polymer (Sample 1-4)

The coupling agent is changed from tetraethoxysilane to 2,2-dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza-2-silacyclopentane (abbreviated as “D” in the table), In the same manner as in Example 1-1, except that the addition amount was changed to 0.0360 mmol/min, some main chains had a four-branched structure derived from the branching agent structure (1), and a four-branched star polymer structure derived from the coupling agent was obtained. A coupling-conjugated diene-based polymer (Sample 1-4) was obtained. Table 1 shows the physical properties of Samples 1-4.

(Example 1-5) Coupling conjugated diene-based polymer (Sample 1-5)

Example 1- Except that the coupling agent was changed from tetraethoxysilane to tris(3-trimethoxysilylpropyl)amine (abbreviated as "E" in the table), and the addition amount was changed to 0.0250 mmol/min. In the same manner as in 1, a coupling conjugated diene-based polymer (Sample 1-5) having a four-branched structure derived from the branching agent structure (1) in a part of the main chain and having a six-branched star-shaped polymer structure derived from the coupling agent was obtained. Table 1 shows the physical properties of Samples 1-5.

(Example 1-6) Coupling conjugated diene-based polymer (Sample 1-6)

The coupling agent was changed from tetraethoxysilane to tetrakis(3-trimethoxysilylpropyl)-1,3-propanediamine (in the table, abbreviated as "F"), and the amount added was changed to 0.0190 mmol/min. Except that, in the same manner as in Example 1-1, a coupling conjugated diene-based polymer having a four-branched structure derived from the branching agent structure (1) in a part of the main chain and an eight-branched star polymer structure derived from the coupling agent (Sample 1) -6) was obtained. Table 1 shows the physical properties of Samples 1-6.

(Example 1-7) Coupling conjugated diene-based polymer (Sample 1-7)

The coupling agent was changed from tetraethoxysilane to tetrakis(3-trimethoxysilylpropyl)-1,3-propanediamine (in the table, abbreviated as “F”), and the amount added was changed to 0.0160 mmol/min. Except that, in the same manner as in Example 1-1, a coupling conjugated diene-based polymer having a four-branched structure derived from the branching agent structure (1) in a part of the main chain and an eight-branched star polymer structure derived from the coupling agent (Sample 1) -7) was obtained. Table 1 shows the physical properties of Samples 1-7.

(Example 1-8) Coupling conjugated diene-based polymer (Sample 1-8)

The addition rate of 1,3-butadiene was changed from 18.6 g/min to 24.3 g/min, the addition rate of styrene was changed from 10.0 g/min to 4.3 g/min, and 2,2-bis(2- The rate of addition of oxolanyl)propane was changed from 0.081 mmol/min to 0.044 mmol/min, and the coupling agent was changed from tetraethoxysilane to tetrakis(3-trimethoxysilylpropyl)-1,3-propanediamine (Table In the same manner as in Example 1-1, except that the addition amount was changed to 0.0160 mmol/min.), a four-branched structure derived from the branching agent structure (1) was added to a part of the main chain in the same manner as in Example 1-1. and a coupling conjugated diene-based polymer (Sample 1-8) having an 8-branched star-shaped polymer structure derived from a coupling agent was obtained. Table 1 shows the physical properties of Samples 1-8.

(Example 1-9) Coupling conjugated diene-based polymer (Sample 1-9)

The addition rate of 1,3-butadiene was changed from 18.6 g/min to 17.1 g/min, the addition rate of styrene was changed from 10.0 g/min to 11.5 g/min, and 2,2-bis(2- The rate of addition of oxolanyl)propane was changed from 0.081 mmol/min to 0.089 mmol/min, and the coupling agent was changed from tetraethoxysilane to tetrakis(3-trimethoxysilylpropyl)-1,3-propanediamine (Table In the same manner as in Example 1-1, except that the addition amount was changed to 0.0160 mmol/min.), a four-branched structure derived from the branching agent structure (1) was added to a part of the main chain in the same manner as in Example 1-1. and a coupling conjugated diene-based polymer (Sample 1-9) having an eight-branched star-shaped polymer structure derived from a coupling agent was obtained. Table 2 shows the physical properties of Samples 1-9.

(Example 1-10) Coupling conjugated diene-based polymer (Sample 1-10)

The rate of addition of 2,2-bis(2-oxolanyl)propane of the polar material was changed from 0.081 mmol/min to 0.200 mmol/min, and the coupling agent was changed from tetraethoxysilane to tetrakis(3-trimethoxysilyl). Propyl)-1,3-propanediamine (in the table, it is abbreviated as "F"), except that the addition amount was changed to 0.0160 mmol/min, it was carried out in the same manner as in Example 1-1, and branched to a part of the main chain. A coupling conjugated diene-based polymer (Sample 1-10) having a four-branched structure derived from the topical structure (1) and an eight-branched star polymer structure derived from a coupling agent was obtained. Table 2 shows the physical properties of Samples 1-10.

(Example 1-11) Coupling conjugated diene-based polymer (Sample 1-11)

The branching agent is changed from trimethoxy (4-vinylphenyl) silane to dimethyl methoxy (4-vinylphenyl) silane (in the table, abbreviated as "BS-2"), the amount added is changed to 0.0350 mmol/min, Example 1- Except that the ring agent was changed from tetraethoxysilane to 1,2-bis(triethoxysilyl)ethane (abbreviated as "B" in the table), and the addition amount was changed to 0.0360 mmol/min. In the same manner as in 1, a coupling conjugated diene-based polymer (Sample 1-11) having a two-branched structure derived from the branching agent structure (1) in a part of the main chain and having a four-branched star polymer structure derived from the coupling agent was obtained. Table 2 shows the physical properties of Samples 1-11.

(Example 1-12) Coupling conjugated diene-based polymer (Sample 1-12)

The branching agent is changed from trimethoxy (4-vinylphenyl) silane to dimethyl methoxy (4-vinylphenyl) silane (in the table, abbreviated as "BS-2"), the amount added is changed to 0.0350 mmol/min, The ring agent was changed from tetraethoxysilane to 2,2-dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza-2-silacyclopentane (abbreviated as “D” in the table), and the In the same manner as in Example 1-1, except that the addition amount was changed to 0.0360 mmol/min, a part of the main chain had a two-branched structure derived from the branching agent structure (1), and had a four-branched star polymer structure derived from a coupling agent. A coupling conjugated diene-based polymer (Sample 1-12) was obtained. Table 2 shows the physical properties of Samples 1-12.

(Example 1-13) Coupling conjugated diene-based polymer (Sample 1-13)

The branching agent is changed from trimethoxy (4-vinylphenyl) silane to dimethyl methoxy (4-vinylphenyl) silane (in the table, abbreviated as "BS-2"), the amount added is changed to 0.0350 mmol/min, Except that the ring agent was changed from tetraethoxysilane to tetrakis(3-trimethoxysilylpropyl)-1,3-propanediamine (abbreviated as "F" in the table), and the addition amount was changed to 0.0160 mmol/min. In the same manner as in Example 1-1, a coupling conjugated diene-based polymer having a two-branched structure derived from the branching agent structure (1) in a part of the main chain and an eight-branched star polymer structure derived from the coupling agent (Sample 1- 13) was obtained. Table 2 shows the physical properties of Samples 1-13.

(Example 1-14) Coupling conjugated diene-based polymer (Sample 1-14)

The branching agent was changed from trimethoxy(4-vinylphenyl)silane to 1,1-bis(4-(dimethylmethoxysilyl)phenyl)ethylene (in the table, abbreviated as "BS-3"), and the amount added was 0.0120 mmol/min, the coupling agent is changed from tetraethoxysilane to 1,2-bis(triethoxysilyl)ethane (abbreviated as "B" in the table), and the addition amount is changed to 0.0360 mmol/min Other than that, in the same manner as in Example 1-1, it has a three-branched structure derived from a branching agent (hereinafter also referred to as "branching agent structure (2)") which is a compound represented by the following formula (2) in a part of the main chain. , A coupling conjugated diene-based polymer (Sample 1-14) having a four-branched star polymer structure derived from a coupling agent was obtained. Table 2 shows the physical properties of Samples 1-14.

(In formula (2), X ² , X ³ is a single bond or an organic group containing any one selected from the group consisting of carbon, hydrogen, nitrogen, sulfur, and oxygen.

Y ² and Y ³ represent any selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, and a halogen atom. Each is independent and may be the same or different.)

(Example 1-15) Coupling conjugated diene-based polymer (Sample 1-15)

The branching agent was changed from trimethoxy(4-vinylphenyl)silane to 1,1-bis(4-(dimethylmethoxysilyl)phenyl)ethylene (in the table, abbreviated as "BS-3"), and the amount added was 0.0120 mmol/min, and the coupling agent is changed from tetraethoxysilane to 2,2-dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza-2-silacyclopentane (referred to as “D” in the table) In the same manner as in Example 1-1, except that the addition amount was changed to 0.0360 mmol/min, a part of the main chain has a three-branched structure derived from the branching agent structure (2), and the coupling agent-derived A coupling conjugated diene-based polymer (Sample 1-15) having a four-branched star polymer structure was obtained. Table 2 shows the physical properties of Samples 1-15.

(Example 1-16) Coupling conjugated diene-based polymer (Sample 1-16)

The branching agent was changed from trimethoxy(4-vinylphenyl)silane to 1,1-bis(4-(dimethylmethoxysilyl)phenyl)ethylene (in the table, abbreviated as "BS-3"), and the amount added was 0.0120 mmol/min, the coupling agent is changed from tetraethoxysilane to tetrakis(3-trimethoxysilylpropyl)-1,3-propanediamine (abbreviated as "F" in the table), and the amount added is 0.0160 A coupling conjugate having a three-branched structure derived from the branching agent structure (2) in a part of the main chain and an eight-branched star polymer structure derived from the coupling agent was carried out in the same manner as in Example 1-1 except that it was changed to mmol/min. A diene-based polymer (Sample 1-16) was obtained. Table 2 shows the physical properties of Samples 1-16.

(Example 1-17) Coupling conjugated diene-based polymer (Sample 1-17)

The branching agent was changed from trimethoxy(4-vinylphenyl)silane to 1,1-bis(4-trimethoxysilylphenyl)ethylene (in the table, abbreviated as "BS-4"), and the amount added was 0.0210 mmol/ Min, except that the coupling agent was changed from tetraethoxysilane to 1,2-bis(triethoxysilyl)ethane (abbreviated as "B" in the table), and the addition amount was changed to 0.0360 mmol/min. , In the same manner as in Example 1-1, a coupling conjugated diene-based polymer having a seven-branched structure derived from the branching agent structure (2) in a part of the main chain and a four-branched star polymer structure derived from the coupling agent (Sample 1-17) ) was obtained. Table 3 shows the physical properties of Samples 1-17.

(Example 1-18) Coupling conjugated diene-based polymer (Sample 1-18)

The branching agent was changed from trimethoxy(4-vinylphenyl)silane to 1,1-bis(4-trimethoxysilylphenyl)ethylene (in the table, abbreviated as "BS-4"), and the amount added was 0.0210 mmol/ minutes, and the coupling agent is abbreviated as "D" in the table from tetraethoxysilane to 2,2-dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza-2-silacyclopentane. ) and having a 7 branched structure derived from the branching agent structure (2) in a part of the main chain in the same manner as in Example 1-1 except that the addition amount was changed to 0.0360 mmol/min, and 4 branches derived from the coupling agent A coupling conjugated diene-based polymer (Sample 1-18) having a star-shaped polymer structure was obtained. Table 3 shows the physical properties of Samples 1-18.

(Example 1-19) Coupling conjugated diene-based polymer (Sample 1-19)

The branching agent was changed from trimethoxy(4-vinylphenyl)silane to 1,1-bis(4-trimethoxysilylphenyl)ethylene (in the table, abbreviated as "BS-4"), and the amount added was 0.0210 mmol/ minutes, and the coupling agent is changed from tetraethoxysilane to tetrakis(3-trimethoxysilylpropyl)-1,3-propanediamine (in the table, abbreviated as "F"), and the amount added is 0.0160 mmol/ A coupling conjugated diene system having a 7-branched structure derived from the branching agent structure (2) in a part of the main chain and an 8-branched star polymer structure derived from the coupling agent in the same manner as in Example 1-1 except that it was changed to A polymer (Sample 1-19) was obtained. Table 3 shows the physical properties of Samples 1-19.

(Example 1-20) Coupling conjugated diene-based polymer (Sample 1-20)

The branching agent is changed from trimethoxy (4-vinylphenyl) silane to trichloro (4-vinylphenyl) silane (in the table, abbreviated as "BS-5"), the amount added is changed to 0.0190 mmol/min, and the coupling agent Example 1-1 except that tetraethoxysilane was changed to 1,2-bis(triethoxysilyl)ethane (abbreviated as "B" in the table), and the amount added was changed to 0.0360 mmol/min. In the same manner as described above, a coupling conjugated diene-based polymer (Sample 1-20) having a four-branched structure derived from the branching agent structure (1) in a part of the main chain and an eight-branched star polymer structure derived from the coupling agent was obtained. Table 3 shows the physical properties of Samples 1-20.

(Example 1-21) Coupling conjugated diene-based polymer (Sample 1-21)

The branching agent is changed from trimethoxy (4-vinylphenyl) silane to trichloro (4-vinylphenyl) silane (in the table, abbreviated as "BS-5"), the amount added is changed to 0.0190 mmol/min, and the coupling agent is changed from tetraethoxysilane to 2,2-dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza-2-silacyclopentane (abbreviated as “D” in the table), and the amount added A couple having a four-branched structure derived from the branching agent structure (1) in a part of the main chain and an eight-branched star polymer structure derived from a coupling agent in the same manner as in Example 1-1 except that 0.0360 mmol/min was changed. A ring conjugated diene-based polymer (Sample 1-21) was obtained. Table 3 shows the physical properties of Sample 1-21.

(Example 1-22) Coupling conjugated diene-based polymer (Sample 1-22)

The branching agent is changed from trimethoxy (4-vinylphenyl) silane to trichloro (4-vinylphenyl) silane (in the table, abbreviated as "BS-5"), the amount added is changed to 0.0190 mmol/min, and the coupling agent was changed from tetraethoxysilane to tetrakis(3-trimethoxysilylpropyl)-1,3-propanediamine (in the table, abbreviated as "F"), and the addition amount was changed to 0.0160 mmol/min. , In the same manner as in Example 1-1, a coupling conjugated diene-based polymer having a four-branched structure derived from the branching agent structure (1) in a part of the main chain and an eight-branched star polymer structure derived from the coupling agent (Sample 1-22) ) was obtained. Table 3 shows the physical properties of Sample 1-22.

(Example 1-23) Coupling conjugated diene-based polymer (Sample 1-23)

The addition amount of trimethoxy(4-vinylphenyl)silane (in the table, abbreviated as "BS-1") of the branching agent was changed from 0.0190 mmol/min to 0.0100 mmol/min, and the coupling agent was changed from tetraethoxysilane to tetrakis. (3-trimethoxysilylpropyl)-1,3-propanediamine (in the table, abbreviated as "F"), except that the addition amount was changed to 0.0190 mmol/min, similarly to Example 1-1 Thus, a coupling conjugated diene-based polymer (Sample 1-23) having a four-branched structure derived from the branching agent structure (1) in a part of the main chain and an eight-branched star polymer structure derived from the coupling agent was obtained. Table 3 shows the physical properties of Sample 1-23.

(Example 1-24) Coupling conjugated diene-based polymer (Sample 1-24)

The addition amount of trimethoxy (4-vinylphenyl) silane (in the table, abbreviated as "BS-1" in the table) of the branching agent was changed from 0.0190 mmol/min to 0.0250 mmol/min, and the coupling agent was changed from tetraethoxysilane to tetrakis (3-trimethoxysilylpropyl)-1,3-propanediamine (in the table, abbreviated as "F"), except that the addition amount was changed to 0.0190 mmol/min, similarly to Example 1-1 Thus, a coupling conjugated diene-based polymer (Sample 1-24) having a four-branched structure derived from the branching agent structure (1) in a part of the main chain and an eight-branched star polymer structure derived from the coupling agent was obtained. Table 4 shows the physical properties of Sample 1-24.

(Example 1-25) Coupling conjugated diene-based polymer (Sample 1-25)

The addition amount of trimethoxy(4-vinylphenyl)silane (in the table, abbreviated as "BS-1" in the table) of the branching agent was changed from 0.0190 mmol/min to 0.0350 mmol/min, and the coupling agent was changed from tetraethoxysilane to tetrakis. (3-trimethoxysilylpropyl)-1,3-propanediamine (in the table, abbreviated as "F"), except that the addition amount was changed to 0.0190 mmol/min, similarly to Example 1-1 Thus, a coupling conjugated diene-based polymer (Sample 1-25) having a four-branched structure derived from the branching agent structure (1) in a part of the main chain and an eight-branched star polymer structure derived from the coupling agent was obtained. Table 4 shows the physical properties of Samples 1-25.

(Example 1-26) Coupling conjugated diene-based polymer (Sample 1-26)

The coupling agent is changed from tetraethoxysilane to tetrakis(3-trimethoxysilylpropyl)-1,3-propanediamine (in the table, abbreviated as "F"), and the addition amount is changed to 0.0190 mmol/min, In the same manner as in Example 1-1, except for changing to SRAE oil added as a rubber softener and changing to liquid rubber (liquid polybutadiene LBR-302 manufactured by Kuraray Co., Ltd.), a branching agent structure (1) was derived in a part of the main chain A coupling conjugated diene-based polymer (Sample 1-26) having a four-branched structure and an eight-branched star-shaped polymer structure derived from a coupling agent was obtained. Table 4 shows the physical properties of Sample 1-26.

(Example 1-27) Coupling conjugated diene-based polymer (Sample 1-27)

The coupling agent is changed from tetraethoxysilane to tetrakis(3-trimethoxysilylpropyl)-1,3-propanediamine (in the table, abbreviated as "F"), and the addition amount is changed to 0.0190 mmol/min, In the same manner as in Example 1-1, except that the SRAE oil added as a rubber softener was changed to a resin (terpene resin YS resin PX1250 manufactured by Yasuhara Chemical Co., Ltd.), some of the main chains of the branching agent structure (1) were A coupling conjugated diene-based polymer (Sample 1-27) having a 4-branched structure and an 8-branched star-shaped polymer structure derived from a coupling agent was obtained. Table 4 shows the physical properties of Sample 1-27.

(Example 1-28) Coupling conjugated diene-based polymer (Sample 1-28)

The coupling agent is changed from tetraethoxysilane to tetrakis(3-trimethoxysilylpropyl)-1,3-propanediamine (in the table, abbreviated as "F"), and the addition amount is changed to 0.0190 mmol/min, 4 derived from the branching agent structure (1) in some main chains in the same manner as in Example 1-1 except that the SRAE oil added as a softener for rubber was changed to naphthenic oil (naphthenic oil Nytex810 manufactured by Nynas) A coupling conjugated diene-based polymer (Sample 1-28) having a branched structure and an eight-branched star-shaped polymer structure derived from a coupling agent was obtained. Table 4 shows the physical properties of Sample 1-28.

(Example 1-29) Coupling conjugated diene-based polymer (Sample 1-29)

The coupling agent is changed from tetraethoxysilane to tetrakis(3-trimethoxysilylpropyl)-1,3-propanediamine (in the table, abbreviated as "F"), and the addition amount is changed to 0.0190 mmol/min, A couple having a four-branched structure derived from the branching agent structure (1) in a part of the main chain and an eight-branched star polymer structure derived from a coupling agent in the same manner as in Example 1-1 except that a softener for rubber was not added A ring conjugated diene-based polymer (Sample 1-29) was obtained. Table 4 shows the physical properties of Sample 1-29.

(Example 1-30) Coupling conjugated diene-based polymer (Sample 1-30)

The coupling agent is changed from tetraethoxysilane to tetrakis(3-trimethoxysilylpropyl)-1,3-propanediamine (in the table, abbreviated as "F"), and the addition amount is changed to 0.0190 mmol/min, In the same manner as in Example 1-1, except that the amount of SRAE oil added as a softener for rubber was changed from 25.0 g to 37.5 g with respect to 100 g of polymer, 4 branches derived from the branching agent structure (1) in a part of the main chain A coupling conjugated diene polymer (Sample 1-30) having a structure and an 8-branched star polymer structure derived from a coupling agent was obtained. Table 4 shows the physical properties of Samples 1-30.

(Example 1-31) Conjugated diene-based polymer (Sample 1-31)

In a place where polymerization is sufficiently stable, trimethoxy(4-vinylphenyl)silane (abbreviated as “BS-1” in the table) as a branching agent is added from the bottom of the second reactor at a rate of 0.0190 mmol/min. In the same manner as in Example 1-1, except that no coupling agent was added, a part of the main chain has a four-branched structure derived from the branching agent structure (1), and does not exhibit a star coupling structure derived from a coupling agent. , a conjugated diene-based polymer (Sample 1-31) was obtained. Table 5 shows the physical properties of Sample 1-31.

(Example 1-32) Coupling conjugated diene-based polymer (Sample 1-32)

In a place where polymerization is sufficiently stable, trimethoxy(4-vinylphenyl)silane (abbreviated as “BS-1” in the table) as a branching agent is added from the bottom of the second reactor at a rate of 0.0190 mmol/min. and, as a coupling agent, tetraethoxysilane (abbreviated as "A" in the table) was changed from 0.0480 mmol/min to 0.0120 mmol/min. A coupling conjugated diene-based polymer (Sample 1-32) having a four-branched structure derived from the branching agent structure (1) in the main chain and a partially three-branched star polymer structure derived from the coupling agent was obtained. Table 5 shows the physical properties of Samples 1-32.

(Example 1-33) Coupling conjugated diene-based polymer (Sample 1-33)

In a place where polymerization is sufficiently stable, trimethoxy(4-vinylphenyl)silane (abbreviated as “BS-1” in the table) as a branching agent is added from the bottom of the second reactor at a rate of 0.0190 mmol/min. and, as a coupling agent, from tetraethoxysilane to tetrakis(3-trimethoxysilylpropyl)-1,3-propanediamine (in the table, abbreviated as "F"), and the amount added was 0.0038 mmol/min. A coupling conjugated diene system having a four-branched structure derived from the branching agent structure (1) in a part of the main chain and a partially eight-branched star polymer structure derived from the coupling agent in the same manner as in Example 1-1 except that it was changed to A polymer (Sample 1-33) was obtained. Table 5 shows the physical properties of Samples 1-33.

(Example 1-34) Coupling conjugated diene-based polymer (Sample 1-34)

In the place where the polymerization is sufficiently stable, from the bottom of the second reactor, dimethylmethoxy(4-vinylphenyl)silane (abbreviated as “BS-2” in the table) as a branching agent is added at a rate of 0.0350 mmol/min. and changing the tetraethoxysilane addition amount of the coupling agent from 0.0480 mmol/min to 0.0120 mmol/min, in the same manner as in Example 1-1, a two branched structure derived from the branching agent structure (1) in some main chains and a coupling conjugated diene-based polymer (Sample 1-34) having a partially three-branched star-shaped polymer structure derived from a coupling agent was obtained. Table 5 shows the physical properties of Samples 1-34.

(Example 1-35) Coupling conjugated diene-based polymer (Sample 1-35)

In a place where polymerization is sufficiently stable, 0.0120 mmol of 1,1-bis(4-(dimethylmethoxysilyl)phenyl)ethylene (abbreviated as “BS-3” in the table) as a branching agent is added from the bottom of the reactor of the second stage. A branching agent structure (2) was added to a part of the main chain in the same manner as in Example 1-1 except that it was added at a rate of /min and the amount of tetraethoxysilane added of the coupling agent was changed from 0.0480 mmol/min to 0.0120 mmol/min. ), a coupling conjugated diene-based polymer (Sample 1-35) having a three-branched structure derived from a coupling agent and having a partially three-branched star polymer structure derived from a coupling agent was obtained. Table 5 shows the physical properties of Samples 1-35.

(Example 1-36) Coupling conjugated diene-based polymer (Sample 1-36)

Example 1 except that the coupling agent was changed from tetraethoxysilane to 3-(benzylideneamino)propyltriethoxysilane (abbreviated as "G" in the table), and the addition amount was changed to 0.0620 mmol/min. In the same manner as -1, a coupling conjugated diene-based polymer (Sample 1-36) having a four-branched structure derived from the branching agent structure (1) in a part of the main chain and a two-branched star polymer structure derived from the coupling agent was obtained. . Table 5 shows the physical properties of Samples 1-36.

(Example 1-37) Coupling conjugated diene-based polymer (Sample 1-37)

1,3-butadiene added to the reactor of the first stage was changed from 18.6 g/min to 13.95 g/min, and from the bottom of the reactor of the second stage, 4.65 g/min of 1,3-butadiene was added simultaneously with the branching agent Except that, in the same manner as in Example 1-1, a coupling conjugated diene polymer having a four-branched structure derived from the branching agent structure (1) in a part of the main chain and a four-branched star polymer structure derived from the coupling agent (sample) 1-37) was obtained. Table 5 shows the physical properties of Samples 1-37.

(Comparative Example 1-1) Coupling conjugated diene-based polymer (Sample 1-38)

The inner volume is 10L, the ratio (L/D) of the inner height (L) to the diameter (D) is 4.0, has an inlet at the bottom, an outlet at the top, and a stirrer, which is a tank reactor having a stirrer, and a jacket for temperature control The tank pressure vessel which had was made into a polymerization reactor, and two groups were connected.

1,3-butadiene, which had been previously dehydrated, was mixed under conditions of 18.6 g/min, styrene at 10.0 g/min, and n-hexane at 175.2 g/min. In a static mixer provided in the middle of a pipe for supplying this mixed solution to the inlet of the reactor, n-butyllithium for inert treatment of residual impurities was added and mixed at 0.103 mmol/min, and then continuously supplied to the bottom of the reactor. In addition, 2,2-bis(2-oxolanyl)propane as a polar material at a rate of 0.081 mmol/min and n-butyllithium as a polymerization initiator at a rate of 0.143 mmol/min were vigorously mixed with a stirrer. The first stage was supplied to the bottom of the reactor, and the internal temperature of the reactor was maintained at 67°C.

The polymer solution was continuously withdrawn from the top of the reactor in the first stage, continuously fed to the bottom of the reactor in the second stage, and the reaction was continued at 70° C., and further fed to the static mixer from the top of the second stage. In a place where polymerization was sufficiently stable, a small amount of the polymer solution before addition of the coupling agent was extracted, and after adding antioxidant (BHT) to 0.2 g per 100 g of polymer, the solvent was removed, and Mooney viscosity at 110 ° C. and various molecular weights were measured. . The physical properties are shown in Table 6.

Then, to the polymer solution flowing out from the outlet of the reactor, as a coupling agent, tetraethoxysilane (abbreviated as "A" in the table) was continuously added at a rate of 0.0480 mmol/min, and mixed using a static mixer. and a coupling reaction was carried out. At this time, the time until the coupling agent is added to the polymer solution flowing out from the outlet of the reactor is 4.8 minutes, the temperature is 68°C, and the difference between the temperature in the polymerization step and the temperature until the coupling agent is added is 2 ℃ was. A small amount of the conjugated diene-based polymer solution after the coupling reaction is extracted, an antioxidant (BHT) is added so that 0.2 g per 100 g of the polymer, and the solvent is removed. ,2-vinyl bond amount: Physical property 7) was measured. Table 6 shows the measurement results.

Next, to the polymer solution subjected to the coupling reaction, an antioxidant (BHT) was continuously added at a rate of 0.055 g/min (n-hexane solution) to 0.2 g per 100 g of the polymer, and the coupling reaction was terminated. Simultaneously with the antioxidant, as a softener for rubber, SRAE oil (JOMO Process NC140 manufactured by JX Nikko Niseki Energy Co., Ltd.) was continuously added to 25.0 g with respect to 100 g of the polymer, and mixed with a static mixer. The solvent was removed by steam stripping to obtain a coupling conjugated diene-based polymer (Sample 1-38) having no branching agent-derived main chain branch and having a three-branched star polymer structure derived from the coupling agent. Table 6 shows the physical properties of Samples 1-38.

(Comparative Example 1-2) Coupling conjugated diene-based polymer (Sample 1-39)

The coupling agent is changed from tetraethoxysilane to 2,2-dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza-2-silacyclopentane (abbreviated as “D” in the table), A coupling conjugated diene polymer (sample) having no main chain branching derived from a branching agent and having a four-branched star polymer structure derived from a coupling agent was carried out in the same manner as in Comparative Example 1-1 except that the addition amount was changed to 0.0360 mmol/min. 1-39) were obtained. Table 6 shows the physical properties of Samples 1-39.

(Comparative Example 1-3) Coupling conjugated diene-based polymer (Sample 1-40)

The coupling agent was changed from tetraethoxysilane to tetrakis(3-trimethoxysilylpropyl)-1,3-propanediamine (in the table, abbreviated as "F"), and the amount added was changed to 0.0190 mmol/min. Except that, in the same manner as in Comparative Example 1-1, a coupling conjugated diene-based polymer (Sample 1-40) having no main chain branching derived from a branching agent and having an 8-branched star-shaped polymer structure derived from a coupling agent was obtained. Table 6 shows the physical properties of Samples 1-40.

(Examples 1-38 to 1-74 and Comparative Examples 1-4 to 1-6)

Samples 1-1 to 1-40 shown in Tables 1 to 6 were used as raw rubber, and rubber compositions containing each raw rubber were obtained according to the formulations shown below.

(rubber component)

· Branched conjugated diene-based polymer and coupling conjugated diene-based polymer (Samples 1-1 to 1-40)

: 80 parts by mass (parts by mass excluding the rubber softener)

· Hysis polybutadiene (trade name "UBEPOL BR150" manufactured by Ube Kosan Corporation)

: 20 parts by mass

(Formulation conditions)

The addition amount of each compounding agent was expressed by mass parts with respect to 100 mass parts of rubber components which do not contain the softener for rubber|gum.

· Silica 1 (trade name "Ultrasil 7000GR" manufactured by Evonik Degussa)

Nitrogen adsorption specific surface area 170 m 2 /g): 50.0 parts by mass

· Silica 2 (trade name "Zeosil Premium 200MP" manufactured by Rhodia Corporation)

Nitrogen adsorption specific surface area 220 m 2 /g): 25.0 parts by mass

・ Carbon black (trade name "Sist KH (N339)" manufactured by Tokai Carbon Corporation)

: 5.0 parts by mass

· Silane coupling agent (trade name "Si75" manufactured by Evonik Degus Corporation, bis(triethoxysilylpropyl)disulfide): 6.0 parts by mass

· SRAE oil (trade name "Process NC140" manufactured by JX Nikko Niseki Energy Corporation)

: 42.0 parts by mass

(Including the amount previously added as a softener for rubber contained in Samples 1-1 to 1-40)

· Zincization: 2.5 parts by mass

· Stearic acid: 1.0 part by mass

· Anti-aging agent (N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine): 2.0 parts by mass

· Sulfur: 2.2 parts by mass

Vulcanization accelerator 1 (N-cyclohexyl-2-benzothiazylsulfinamide)

: 1.7 parts by mass

Vulcanization accelerator 2 (diphenylguanidine): 2.0 parts by mass

· Total: 239.4 parts by mass

(Kneading method)

The above materials were kneaded by the following method to obtain a rubber composition. Using a sealed kneader (content 0.3L) equipped with a temperature control device, the raw rubber (Samples 1-1 to 1-40) was kneaded in the first stage under the conditions of a filling rate of 65% and a rotor rotation speed of 30 to 50 rpm. ), fillers (silica 1, silica 2, carbon black), silane coupling agent, SRAE oil, zinc oxide and stearic acid were kneaded. At this time, the temperature of the hermetic mixer was controlled to obtain each rubber composition (formulation) at a discharge temperature of 155 to 160°C.

Then, as a second stage of kneading, the blend obtained above was cooled to room temperature, an antioxidant was added, and kneaded again to improve the dispersion of silica. Also in this case, the discharge temperature of the compound was adjusted to 155 to 160°C by temperature control of the mixer.

After cooling, as kneading in the third stage, sulfur and vulcanization accelerators 1 and 2 were added and kneaded in an open roll set at 70°C.

Then, it shape|molded and it vulcanized|vulcanized by the vulcanization press for 20 minutes at 160 degreeC.

The rubber composition before vulcanization and the rubber composition after vulcanization were evaluated. Specifically, it evaluated by the following method. The results are shown in Tables 7 to 12.

[Evaluation of characteristics]

(Evaluation 1) formulation Mooney viscosity

After kneading in the second stage obtained above and before kneading in the third stage as a sample, using a Mooney viscometer, in accordance with ISO 289, after preheating at 130° C. for 1 minute, the rotor is rotated at 2 per minute The viscosity after rotating by rotation for 4 minutes was measured. The result of Comparative Example 1-4 was made into 100, and it was indexed. It shows that workability is so good that an index|index is small.

(Evaluation 2) Tensile strength and tensile elongation

Based on the tensile test method of JIS K6251, tensile strength and tensile elongation were measured, and the result of Comparative Example 1-4 was made into 100, and it was indexed. It shows that the tensile strength and tensile elongation (breaking strength) are so good that an index|index is large.

(Evaluation 3) Wear resistance

Using an Akron abrasion tester (manufactured by Yasuda Seiki Seisakusho Co., Ltd.), in accordance with JIS K6264-2, the amount of wear at a load of 44.4 N and 1000 rotations was measured, and the result of Comparative Example 1-4 was set to 100 and indexed. It shows that abrasion resistance is so good that an index|index is large.

(Evaluation 4) Viscoelastic parameters

Viscoelasticity parameters were measured in torsion mode using the viscoelasticity tester "ARES" manufactured by Rheometrics Scientific. Each measured value was indexed by taking the result for the rubber composition of Comparative Example 1-4 as 100.

In 0 degreeC, tan-delta measured with the frequency of 10 Hz and strain 1% was made into the parameter|index of wet-skid property. It shows that wet-skid property is so good that an index|index is large.

In addition, in 50 degreeC, tan δ measured at a frequency of 10 Hz and a strain of 3% was used as an index of fuel efficiency. It shows that fuel economy saving property is so good that an index|index is small.

In addition, the elastic modulus (G') measured at 50 degreeC with the frequency of 10 Hz and the strain 3% was made into the parameter|index of steering stability. The larger the index, the better the steering stability.

As shown in Tables 7 to 12, Examples 1-38 to 1-74, compared with Comparative Examples 1-4 to 1-6, showed good processability due to low formulation Mooney viscosity when used as a vulcanized product, It was confirmed that the vulcanized product was excellent in abrasion resistance, handling stability and breaking strength, and was excellent in the balance between low hysteresis loss and wet skid resistance.

[Second embodiment]

Hereinafter, various physical properties of Examples and Comparative Examples in [Example 2] were measured by the methods shown below.

In the following, the conjugated diene-based polymer coupled with a nitrogen atom-containing modifier containing a predetermined compound is described as a “coupling conjugated diene-based polymer”.

In addition, the conjugated diene-type polymer of an unmodified state is described as "unmodified conjugated diene-type polymer."

In addition, the conjugated diene-type polymer which has a branched structure is described as "branched conjugated diene-type polymer."

(Physical Properties 1) Polymer Mooney Viscosity

An unmodified conjugated diene-based polymer or a conjugated diene-based polymer coupled with a nitrogen atom-containing modifier (hereinafter also referred to as “coupling conjugated diene-based polymer”) was used as a sample, and a Mooney viscometer (manufactured by Uejima Seisakusho Co., Ltd.) was used as a sample. Using the brand name "VR1132"), according to ISO 289, the Mooney viscosity was measured using the L-type rotor.

The measurement temperature was made into 110 degreeC when making an unmodified conjugated diene-type polymer into a sample, and made into 100 degreeC when using a coupling conjugated diene-type polymer as a sample.

First, after preheating a sample at the test temperature for 1 minute, the rotor was rotated at 2 rpm, the torque after 4 minutes was measured, and it was set as Mooney viscosity (ML ₍₁₊₄₎ ).

(Physical property 2) Mooney relaxation rate

Using a coupling conjugated diene polymer as a sample, using a Mooney viscometer (trade name "VR ¹ 132" manufactured by Uejima Seisakusho Co., Ltd.), according to ISO 289, after measuring the Mooney viscosity using an L-type rotor , immediately stop the rotation of the rotor, record the torque every 0.1 seconds for 1.6 seconds to 5 seconds after stopping, in Mooney units, find the slope of the straight line when the torque and time (seconds) are plotted as both logarithms, and the absolute value is the Mooney This is called the rate of relaxation (MSR).

(Physical property 3) Branching degree (Bn)

The degree of branching (Bn) of the coupling conjugated diene polymer was measured as follows by a GPC-light scattering method having a viscosity detector.

Using a coupling conjugated diene polymer as a sample and a gel permeation chromatography (GPC) measuring apparatus (trade name "GPCmax VE-2001" manufactured by Malvern) in which three columns using polystyrene gel as a filler were connected, light scattering A detector, an RI detector, and a viscosity detector (trade name "TDA305" manufactured by Malvern) are used for measurement using three detectors connected in this order, and based on standard polystyrene, the absolute molecular weight is determined from the results of the light scattering detector and the RI detector, RI The intrinsic viscosity was calculated|required from the result of a detector and a viscosity detector.

A linear polymer, the intrinsic viscosity [η] = - use conforms to the 3.883M ^0.771, the shrinkage factor was calculated (g ') as the intrinsic viscosity ratio corresponding to the molecular weight. In addition, in formula, M represents an absolute molecular weight.

Then, the degree of branching (Bn) defined as g'=6Bn/{(Bn+1)(Bn+2)} was calculated using the obtained shrinkage factor g'.

As the eluent, 5 mmol/L of triethylamine-containing tetrahydrofuran (hereinafter also referred to as “THF”) was used.

The column was used by connecting the brand names "TSKgel G4000HXL", "TSKgel G5000HXL" and "TSKgel G6000HXL" manufactured by Tosoh Corporation.

20 mg of the sample for measurement was dissolved in 10 mL of THF to prepare a measurement solution, 100 µL of the measurement solution was poured into a GPC measuring apparatus, and the measurement was performed under the conditions of an oven temperature of 40°C and a THF flow rate of 1 mL/min.

(Physical Properties 4) Molecular Weight

<Measurement condition 1>:

Using an unmodified conjugated diene-based polymer or a coupling conjugated diene-based polymer as a sample, and a GPC measuring device (trade name "HLC-8320GPC" manufactured by Tosoh Corporation) in which three columns using polystyrene gel as a filler are connected, The chromatogram was measured using an RI detector (trade name "HLC8020" manufactured by Tosoh Corporation), and based on a calibration curve obtained using standard polystyrene, the weight average molecular weight (Mw), the number average molecular weight (Mn), and the molecular weight distribution (Mw/ Mn) was found.

As the eluent, 5 mmol/L of triethylamine-containing THF (tetrahydrofuran) was used. The column was used by connecting three trade names "TSKgel SuperMultiporeHZ-H" manufactured by Tosoh Corporation, and connecting the trade name "TSKguardcolumn SuperMP(HZ)-H" manufactured by Tosoh Corporation to the preceding stage as a guard column.

10 mg of the sample for measurement was dissolved in 10 mL of THF to obtain a measurement solution, 10 µL of the measurement solution was poured into a GPC measuring apparatus, and the measurement was performed under the conditions of an oven temperature of 40°C and a THF flow rate of 0.35 mL/min.

Among the various samples measured under the measurement condition 1 described above, the sample having a molecular weight distribution (Mw/Mn) of less than 1.6 was further measured under the measurement condition 2 below. It measured on the measurement condition 1, and about the sample whose molecular weight distribution value was 1.6 or more, it measured on the measurement condition 1.

<Measurement condition 2>:

Using an unmodified conjugated diene-based polymer or a coupling conjugated diene-based polymer as a sample, the chromatogram was measured using a GPC measuring device in which three columns using polystyrene gel as a filler were connected, and a calibration curve using standard polystyrene Based on this, the weight average molecular weight (Mw) and the number average molecular weight (Mn) were calculated|required.

As the eluent, 5 mmol/L of triethylamine-containing THF was used. As the column, guard column: Tosoh Corporation brand name "TSKguardcolumn SuperH-H", Column: Tosoh Corporation brand name "TSKgel SuperH5000", "TSKgel SuperH6000", and "TSKgel SuperH7000" were used.

An RI detector (trade name "HLC8020" manufactured by Tosoh Corporation) was used under the conditions of an oven temperature of 40°C and a THF flow rate of 0.6 mL/min. 10 mg of the sample for a measurement was melt|dissolved in 20 mL of THF, it was set as the measurement solution, 20 microliters of the measurement solutions were poured into the GPC measuring apparatus, and it measured.

It measured on the measurement condition 1, and about the sample whose molecular weight distribution value was less than 1.6, it measured on the measurement condition 2.

(physical property 5) rate of denaturation

The rate of modification of the coupling conjugated diene polymer was measured by column adsorption GPC method as follows.

It measured by applying the characteristic which the modified|denatured basic polymer component adsorb|sucks to the GPC column which used a coupling conjugated diene type polymer as a sample and used silica gel as a filler.

The amount of adsorption to the silica column was measured from the difference between the chromatogram measured by the polystyrene column and the chromatogram measured by the silica column for the sample solution and the sample solution containing the low molecular weight internal standard polystyrene to determine the denaturation rate. .

Specifically, it is as showing below.

In addition, it measured on the measurement condition 1 of the above-mentioned (physical property 4), and about the sample whose molecular weight distribution value was 1.6 or more, it measured on the measurement condition 3 below. It was measured under the measurement condition 1 of the said (physical property 4), and about the sample whose molecular weight distribution value was less than 1.6, it measured under the measurement condition 4 below.

<Preparation of sample solution>:

10 mg of the sample and 5 mg of standard polystyrene were dissolved in 20 mL of THF to prepare a sample solution.

<Measurement condition 3>:

GPC measurement conditions using a polystyrene-based column:

Using the trade name "HLC-8320GPC" manufactured by Tosoh Corporation, using 5 mmol/L of triethylamine-containing THF as the eluent, 10 μL of the sample solution was injected into the apparatus, and the column oven temperature was 40° C., and the THF flow rate was 0.35 mL/min. Under the conditions, chromatograms were obtained using an RI detector.

The column was used by connecting three trade names "TSKgel SuperMultiporeHZ-H" manufactured by Tosoh Corporation, and connecting the trade name "TSKguardcolumn SuperMP(HZ)-H" manufactured by Tosoh Corporation to the preceding stage as a guard column.

<Measurement condition 4>:

Using THF with 5 mmol/L of triethylamine as the eluent, 20 μL of the sample solution was injected into the device and measured.

As the column, guard column: Tosoh Corporation brand name "TSKguardcolumn SuperH-H", Column: Tosoh Corporation brand name "TSKgel SuperH5000", "TSKgel SuperH6000", and "TSKgel SuperH7000" were used. It measured using the RI detector (HLC8020 by Tosoh Corporation) on the conditions of the column oven temperature of 40 degreeC and the THF flow volume of 0.6 mL/min, and obtained the chromatogram.

GPC measurement conditions using a silica-based column:

Using the trade name "HLC-8320GPC" manufactured by Tosoh Corporation, using THF as the eluent, 50 µL of the sample solution was injected into the device, and the RI detector was used at a column oven temperature of 40° C. and a THF flow rate of 0.5 mL/min. A chromatogram was obtained. The column was used by connecting trade names "Zorbax PSA-1000S", "PSA-300S", and "PSA-60S", and connecting and using the trade name "DIOL 4.6 x 12.5 mm 5micron" as a guard column in the preceding stage.

To calculate the rate of denaturation:

The total peak area of the chromatogram using the polystyrene column is 100, the peak area of the sample is P1, the peak area of the standard polystyrene is P2, and the total of the peak area of the chromatogram using the silica column is 100, and the sample The denaturation rate (%) was calculated|required from the following formula, making the peak area of P3 and the peak area of standard polystyrene P4.

Modification rate (%) = [1-(P2×P3)/(P1×P4)]×100

(However, P1+P2=P3+P4=100)

(Physical property 6) Amount of bound styrene

A coupling conjugated diene-based polymer containing no softener for rubber was used as a sample, and 100 mg of the sample was weighed up to 100 mL with chloroform and dissolved to obtain a measurement sample.

The amount (mass %) of bound styrene with respect to 100 mass % of the coupling conjugated diene polymer which is a sample was measured based on the absorption amount of the ultraviolet absorption wavelength (254 nm vicinity) by the phenyl group of styrene (measuring apparatus: Shimadzu Corporation make. of the spectrophotometer "UV-2450").

(Physical property 7) Microstructure of butadiene moiety (1,2-vinyl bond amount)

A coupling conjugated diene-based polymer containing no softener for rubber was used as a sample, and 50 mg of the sample was dissolved in 10 mL of carbon disulfide to obtain a measurement sample.

Using a solution cell, the infrared spectrum ^{was measured in the range of 600 to 1000 cm -1} , and the absorbance at a predetermined wavenumber was determined by Hampton's method (method described in RR Hampton, Analytical Chemistry 21, 923 (1949)). The microstructure of the butadiene moiety, that is, the amount of 1,2-vinyl bonds (mol%) was determined according to the formula of (Measuring device: Fourier transform infrared spectrophotometer "FT-IR230" manufactured by Nippon Bunko Corporation).

(Physical property 8) Molecular weight by GPC-light scattering method measurement (absolute molecular weight Mw-i)

Using a coupling conjugated diene polymer as a sample and a GPC-light scattering measuring device in which three columns with polystyrene gel as a filler are connected, the chromatogram is measured, and the weight average molecular weight is based on the solution viscosity and the light scattering method. (Mw-i) was calculated|required (it is also called "absolute molecular weight".).

As the eluent, a mixed solution of tetrahydrofuran and triethylamine (THF in TEA: 5 mL of triethylamine was mixed with 1 L of tetrahydrofuran and prepared.).

The column was used by connecting a guard column: "TSKguardcolumn HHR-H" manufactured by Tosoh Corporation, and a column: "TSKgel G6000HHR", "TSKgel G5000HHR", "TSKgel G4000HHR" manufactured by Tosoh Corporation.

On the conditions of an oven temperature of 40 degreeC, and THF flow volume 1.0 mL/min, the GPC-light scattering measuring apparatus (trade name "Viscotek TDAmax" manufactured by Malvern Corporation) was used.

10 mg of the sample for a measurement was melt|dissolved in 20 mL of THF, it was set as the measurement solution, 200 microliters of the measurement solutions were injected into the GPC measuring apparatus, and it measured.

(Evaluation 9) Change over time (Money viscosity increase after 1 month)

The coupling conjugated diene-based polymer was stored at room temperature and pressure for 1 month, and the Mooney viscosity after storage was measured, and the difference from the Mooney viscosity measured immediately after polymerization was calculated.

In a table|surface, it shows as "delta ML Mooney viscosity".

It shows that there are few changes with time, and it is excellent in quality stability, so that a value is small.

[Branched Conjugated Diene-Based Polymer]

(Example 2-1) Branched conjugated diene-based polymer (Sample 2-1)

The inner volume is 10L, the ratio (L/D) of the inner height (L) to the diameter (D) is 4.0, has an inlet at the bottom, an outlet at the top, and a stirrer, which is a tank reactor having a stirrer, and a jacket for temperature control The tank pressure vessel which had was made into a polymerization reactor, and two groups were connected.

1,3-butadiene, which had been previously dehydrated, was mixed under the conditions of 18.6 g/min, styrene at 10.0 g/min, and n-hexane at 175.2 g/min. In a static mixer provided in the middle of a pipe for supplying this mixed solution to the inlet of the reactor, n-butyllithium for inert treatment of residual impurities was added and mixed at 0.103 mmol/min, and then continuously supplied to the bottom of the reactor. In addition, 2,2-bis(2-oxolanyl)propane as a polar material at a rate of 0.081 mmol/min and n-butyllithium as a polymerization initiator at a rate of 0.143 mmol/min were vigorously mixed with a stirrer. The first stage was supplied to the bottom of the reactor, and the internal temperature of the reactor was maintained at 67°C.

The polymer solution was continuously withdrawn from the top of the reactor in the first stage, continuously fed to the bottom of the reactor in the second stage to continue the reaction at 70° C., and further fed to a static mixer from the top of the second stage. In the place where polymerization is sufficiently stable, while copolymerizing 1,3-butadiene and styrene, from the bottom of the second reactor, trimethoxy(4-vinylphenyl)silane as a branching agent (in the table, "BS-1" is shortened) .) was added at a rate of 0.0190 mmol/min, and a polymerization reaction and branching reaction were performed to obtain a conjugated diene-based polymer having a branched main chain structure.

In addition, in a place where the polymerization reaction and branching reaction are stable, a small amount of the conjugated diene-based polymer solution before the addition of the modifier is extracted, and after adding the antioxidant (BHT) so that it becomes 0.2 g per 100 g of the polymer, the solvent is removed, and the solvent is removed at 110 ° C. Viscosity and various molecular weights were measured. The physical properties are shown in Table 13.

Next, to the polymer solution flowing out from the outlet of the reactor, as a coupling agent, compound A-1 (a compound shown in (A-1) among the <compound [A] used in the above-mentioned <modification step]>). In the table, "A -1") was continuously added at a rate of 0.0360 mmol/min, mixed using a static mixer, and a coupling reaction was carried out. At this time, the time until the modifier was added to the polymer solution flowing out from the outlet of the reactor was 4.8 minutes, the temperature was 68°C, and the difference between the temperature in the polymerization step and the temperature until the modifier was added was 2°C. .

After the coupling reaction, a small amount of the conjugated diene-based polymer solution is extracted, an antioxidant (BHT) is added so that 0.2 g per 100 g of the polymer, and the solvent is removed, and the amount of bound styrene (physical property 6) and the microstructure of the butadiene portion (1 ,2-vinyl bond amount: Physical property 7) was measured. Table 13 shows the measurement results.

Next, to the polymer solution subjected to the coupling reaction, an antioxidant (BHT) was continuously added at a rate of 0.055 g/min (n-hexane solution) to 0.2 g per 100 g of the polymer, and the coupling reaction was terminated. Simultaneously with the antioxidant, as a softener for rubber, SRAE oil (JOMO Process NC140 manufactured by JX Nikko Niseki Energy Co., Ltd.) was continuously added to 25.0 g with respect to 100 g of the polymer, and mixed with a static mixer. The solvent was removed by steam stripping to obtain a branched conjugated diene-based polymer (Sample 2-1).

Table 13 shows the physical properties of Sample 2-1.

In addition, with respect to the polymer before the addition of the branching agent, the polymer after the addition of the branching agent, and the polymer in each step after the addition of the coupling agent, the molecular weight by GPC measurement and the degree of branching by GPC measurement with a viscometer are compared by comparison of branching. The structure of the conjugated diene-based polymer was identified. Hereinafter, the structure of each sample was similarly identified.

(Example 2-2) Branched conjugated diene-based polymer (Sample 2-2)

The coupling agent is a compound represented by (A-2) in the <Compound [A]> used in the above <modification step> from the compound A-1 to the compound A-2. In the table, it is abbreviated as "A-2". A branched conjugated diene-based polymer (Sample 2-2) was obtained in the same manner as in Example 2-1 except for changing to .

Table 13 shows the physical properties of Sample 2-2.

(Example 2-3) Branched conjugated diene-based polymer (Sample 2-3)

The coupling agent is a compound represented by (A-4) in the <Compound [A]> used in the above <modification step> from the compound A-1 to the compound A-4. In the table, it is abbreviated as "A-4". A branched conjugated diene-based polymer (Sample 2-3) was obtained in the same manner as in Example 2-1 except that the amount was changed to 0.0720 mmol/min.

Table 13 shows the physical properties of Sample 2-3.

(Example 2-4) Branched conjugated diene-based polymer (Sample 2-4)

A coupling agent is a compound represented by (A-6) in the <Compound [A]> used in the said <modification process> from compound A-1 to compound A-6. In the table|surface, abbreviation "A-6".) A branched conjugated diene-based polymer (Sample 2-4) was obtained in the same manner as in Example 2-1 except for changing to .

Table 13 shows the physical properties of Samples 2-4.

(Example 2-5) Branched conjugated diene-based polymer (Sample 2-5)

A coupling agent is a compound represented by (A-8) in the <Compound [A]> used in the said <modification process> from compound A-1 to compound A-8. In the table|surface, it abbreviates to "A-8".) A branched conjugated diene-based polymer (Sample 2-5) was obtained in the same manner as in Example 2-1 except that the addition amount was changed to 0.0720 mmol/min.

Table 13 shows the physical properties of Samples 2-5.

(Example 2-6) Branched conjugated diene-based polymer (Sample 2-6)

A coupling agent is a compound represented by (A-9) in the <Compound [A]> used in the said <modification step> from compound A-1 to compound A-9. In the table|surface, abbreviation "A-9".) A branched conjugated diene-based polymer (Sample 2-6) was obtained in the same manner as in Example 2-1 except for changing to .

Table 13 shows the physical properties of Samples 2-6.

(Example 2-7) Branched conjugated diene-based polymer (Sample 2-7)

A coupling agent is a compound represented by (A-10) in the <Compound [A]> used in the said <modification step> from compound A-1 to compound A-10. In the table|surface, it abbreviates as "A-10." A branched conjugated diene-based polymer (Sample 2-7) was obtained in the same manner as in Example 2-1 except for changing to .

Table 13 shows the physical properties of Samples 2-7.

(Example 2-8) Branched conjugated diene-based polymer (Sample 2-8)

A coupling agent is a compound represented by (A-12) in the <Compound [A]> used in the said <modification process> from compound A-1 to compound A-12. In the table|surface, it is abbreviated as "A-12." A branched conjugated diene-based polymer (Sample 2-8) was obtained in the same manner as in Example 2-1 except that the amount was changed to 0.0720 mmol/min.

Table 13 shows the physical properties of Samples 2-8.

(Example 2-9) Branched conjugated diene-based polymer (Sample 2-9)

A coupling agent is a compound represented by (A-13) in the <compound [A]> used in the said <denaturation process> from compound A-1 to compound A-13. In the table|surface, it abbreviates as "A-13." A branched conjugated diene-based polymer (Sample 2-9) was obtained in the same manner as in Example 2-1 except that the addition amount was changed to 0.0160 mmol/min.

Table 13 shows the physical properties of Samples 2-9.

(Example 2-10) Branched conjugated diene-based polymer (Sample 2-10)

A coupling agent is a compound represented by (A-14) in the <Compound [A]> used in the said <denaturation step> from compound A-1 to compound A-14. In the table|surface, abbreviation "A-14".) A branched conjugated diene-based polymer (Sample 2-10) was obtained in the same manner as in Example 2-1 except that the amount was changed to 0.0160 mmol/min.

Table 13 shows the physical properties of Samples 2-10.

(Example 2-11) Branched conjugated diene-based polymer (Sample 2-11)

The coupling agent is a compound represented by (A-15) in the <Compound [A]> used in the aforementioned <modification step> from the compound A-1 to the compound A-15. In the table, it is abbreviated as "A-15". A branched conjugated diene-based polymer (Sample 2-11) was obtained in the same manner as in Example 2-1 except that the amount was changed to 0.0360 mmol/min.

Table 13 shows the physical properties of Samples 2-11.

(Example 2-12) Branched conjugated diene-based polymer (Sample 2-12)

The branching agent was changed from trimethoxy (4-vinylphenyl) silane to dimethyl methoxy (4-vinylphenyl) silane (in the table, abbreviated as "BS-2"), and the addition amount was changed to 0.0350 mmol/min. was carried out in the same manner as in Example 2-1 to obtain a branched conjugated diene-based polymer (Sample 2-12).

Table 14 shows the physical properties of Samples 2-12.

(Example 2-13) Branched conjugated diene-based polymer (Sample 2-13)

The branching agent is changed from trimethoxy (4-vinylphenyl) silane to dimethyl methoxy (4-vinylphenyl) silane (in the table, abbreviated as "BS-2"), the amount added is changed to 0.0350 mmol/min, Ring agent from compound A-1 to compound A-2 (a compound represented by (A-2) in the <compound [A]> used in the above-mentioned <modification step. In the table, it is abbreviated as "A-2".) Except having changed, it carried out similarly to Example 2-1, and obtained the branched conjugated diene type polymer (Sample 2-13).

Table 14 shows the physical properties of Samples 2-13.

(Example 2-14) Branched conjugated diene-based polymer (Sample 2-14)

The branching agent is changed from trimethoxy (4-vinylphenyl) silane to dimethyl methoxy (4-vinylphenyl) silane (in the table, abbreviated as "BS-2"), the amount added is changed to 0.0350 mmol/min, The ring agent is changed from compound A-1 to compound A-14 (a compound represented by (A-14) in the above <compound [A]> used in the modification step. In the table, it is abbreviated as “A-14”.) , A branched conjugated diene-based polymer (Sample 2-14) was obtained in the same manner as in Example 2-1 except that the addition amount was changed to 0.0160 mmol/min.

Table 14 shows the physical properties of Samples 2-14.

(Example 2-15) Branched conjugated diene-based polymer (Sample 2-15)

The branching agent was changed from trimethoxy(4-vinylphenyl)silane to 1,1-bis(4-(dimethylmethoxysilyl)phenyl)ethylene (in the table, abbreviated as "BS-3"), and the amount added was 0.0120 A branched conjugated diene-based polymer (Sample 2-15) was obtained in the same manner as in Example 2-1 except that it was changed to mmol/min.

Table 14 shows the physical properties of Samples 2-15.

(Example 2-16) Branched conjugated diene-based polymer (Sample 2-16)

The branching agent was changed from trimethoxy(4-vinylphenyl)silane to 1,1-bis(4-(dimethylmethoxysilyl)phenyl)ethylene (in the table, abbreviated as "BS-3"), and the amount added was 0.0120 mmol/min, and the coupling agent is changed from compound A-1 (in the table, abbreviated as "A-1") to compound A-2 (compound [A] used in the above <denaturation step]>, (A-2 ), which is abbreviated as "A-2" in the table), except that the addition amount was changed to 0.0360 mmol/min. In the same manner as in Example 2-1, the branched conjugated diene polymer ( Samples 2-16) were obtained.

Table 14 shows the physical properties of Samples 2-16.

(Example 2-17) Branched conjugated diene-based polymer (Sample 2-17)

The branching agent was changed from trimethoxy(4-vinylphenyl)silane to 1,1-bis(4-(dimethylmethoxysilyl)phenyl)ethylene (in the table, abbreviated as "BS-3"), and the amount added was 0.0120 mmol/min, and the coupling agent is changed from compound A-1 (in the table, abbreviated as "A-1") to compound A-14 (in the <compound [A] used in the above-mentioned <denaturation step]>, (A-14 ), which is abbreviated as "A-14" in the table), except that the addition amount was changed to 0.0160 mmol/min. In the same manner as in Example 2-1, the branched conjugated diene polymer ( Samples 2-17) were obtained.

Table 14 shows the physical properties of Samples 2-17.

(Example 2-18) Branched conjugated diene-based polymer (Sample 2-18)

The branching agent was changed from trimethoxy(4-vinylphenyl)silane to 1,1-bis(4-trimethoxysilylphenyl)ethylene (in the table, abbreviated as "BS-4"), and the amount added was 0.0210 mmol/ A branched conjugated diene-based polymer (Sample 2-18) was obtained in the same manner as in Example 2-1 except that it was changed to minutes.

Table 14 shows the physical properties of Samples 2-18.

(Example 2-19) Branched conjugated diene-based polymer (Sample 2-19)

The branching agent was changed from trimethoxy(4-vinylphenyl)silane to 1,1-bis(4-trimethoxysilylphenyl)ethylene (in the table, abbreviated as "BS-4"), and the amount added was 0.0210 mmol/ minutes, and the coupling agent is changed from compound A-1 (in the table, abbreviated as "A-1") to compound A-2 (in the <compound [A] used in the above-mentioned <denaturation step]>, to (A-2) A branched conjugated diene-based polymer (Sample 2) in the same manner as in Example 2-1, except that it was changed to “A-2” in the table and the amount added was changed to 0.0360 mmol/min. -19) was obtained.

Table 14 shows the physical properties of Samples 2-19.

(Example 2-20) Branched conjugated diene-based polymer (Sample 2-20)

The branching agent was changed from trimethoxy (4-vinylphenyl) silane to 1,1-bis (4-trimethoxysilylphenyl) ethylene (in the table, abbreviated as "BS-4"), and the coupling agent was changed to Compound A- 1 (in the table, abbreviated as "A-1") to compound A-14 (a compound shown in (A-14) among the <compound [A] used in the above-mentioned modification step>>). In the table, "A- 14"), except that the addition amount was changed to 0.0160 mmol/min, it carried out similarly to Example 2-1, and obtained the branched conjugated diene type polymer (Sample 2-20).

Table 14 shows the physical properties of Samples 2-20.

(Example 2-21) Branched conjugated diene-based polymer (Sample 2-21)

Except that the branching agent was changed from trimethoxy(4-vinylphenyl)silane to trichloro(4-vinylphenyl)silane (abbreviated as "BS-5" in the table) and the amount added was changed to 0.0190 mmol/min. , A branched conjugated diene-based polymer (Sample 2-21) was obtained in the same manner as in Example 2-1.

Table 14 shows the physical properties of Sample 2-21.

(Example 2-22) Branched conjugated diene-based polymer (Sample 2-22)

The branching agent is changed from trimethoxy (4-vinylphenyl) silane to trichloro (4-vinylphenyl) silane (in the table, abbreviated as "BS-5"), the amount added is changed to 0.0190 mmol/min, and the coupling agent is a compound shown in (A-2) from compound A-1 (in the table, abbreviated as "A-1") to compound A-2 (in the <compound [A] used in the modification step>> above. , abbreviated as "A-2."), except that the addition amount was changed to 0.0360 mmol/min, a branched conjugated diene-based polymer (Sample 2-22) was obtained in the same manner as in Example 2-1.

Table 14 shows the physical properties of Sample 2-22.

(Example 2-23) Branched conjugated diene-based polymer (Sample 2-23)

The branching agent is changed from trimethoxy (4-vinylphenyl) silane to trichloro (4-vinylphenyl) silane (in the table, abbreviated as "BS-5"), the amount added is changed to 0.0190 mmol/min, and the coupling agent from compound A-1 (in the table, abbreviated as "A-1") to compound A-14 (a compound represented by (A-14) in the <compound [A] used in the modification step>> above. , abbreviated as "A-14.") and the addition amount was changed to 0.0160 mmol/min, in the same manner as in Example 2-1 to obtain a branched conjugated diene-based polymer (Sample 2-23).

Table 14 shows the physical properties of Sample 2-23.

(Example A-1) Branched conjugated diene-based polymer (Sample A-1)

The inner volume is 10L, the ratio (L/D) of the inner height (L) to the diameter (D) is 4.0, has an inlet at the bottom, an outlet at the top, and a stirrer, which is a tank reactor having a stirrer, and a jacket for temperature control The tank pressure vessel which had was made into a polymerization reactor, and two groups were connected.

1,3-butadiene, which had been previously dehydrated, was mixed under the conditions of 14.0 g/min, styrene at 10.0 g/min, and n-hexane at 175.2 g/min. In a static mixer provided in the middle of a pipe for supplying this mixed solution to the inlet of the reactor, n-butyllithium for inert treatment of residual impurities was added and mixed at 0.103 mmol/min, and then continuously supplied to the bottom of the reactor. In addition, 2,2-bis(2-oxolanyl)propane as a polar material at a rate of 0.081 mmol/min and n-butyllithium as a polymerization initiator at a rate of 0.143 mmol/min were vigorously mixed with a stirrer. The first stage was supplied to the bottom of the reactor, and the internal temperature of the reactor was maintained at 67°C.

The polymer solution was continuously withdrawn from the top of the reactor in the first stage, continuously fed to the bottom of the reactor in the second stage to continue the reaction at 70° C., and further fed to a static mixer from the top of the second stage. In the place where polymerization is sufficiently stable, while copolymerizing 1,3-butadiene and styrene, from the bottom of the second reactor, trimethoxy(4-vinylphenyl)silane as a branching agent (in the table, “BS-1” is reduced) .) was added at a rate of 0.0190 mmol/min and concurrently with 1,3-butadiene at 4.6 g/min, and polymerization reaction and branching reaction were performed to obtain a conjugated diene-based polymer having a branched main chain structure.

In addition, in a place where the polymerization reaction and branching reaction are stable, a small amount of the conjugated diene-based polymer solution before addition of the coupling agent is extracted, and after adding the antioxidant (BHT) so that it becomes 0.2 g per 100 g of the polymer, the solvent is removed, and the Mooney viscosity and various molecular weights were measured. The physical properties are shown in Table 15.

Next, to the polymer solution flowing out from the outlet of the reactor, as a coupling agent, from compound A-1 to compound A-9 (a compound represented by (A-9) among the <compound [A] used in the above-mentioned <denaturation step]> In the table, it is abbreviated as "A-9."), the addition amount was continuously added at 0.0360 mmol/min, mixed using a static mixer, and coupling reaction was carried out.

At this time, the time until the coupling agent is added to the polymer solution flowing out from the outlet of the reactor is 4.8 minutes, the temperature is 68°C, and the difference between the temperature in the polymerization step and the temperature until the coupling agent is added is 2 ℃ was.

After the coupling reaction, a small amount of the conjugated diene-based polymer solution is extracted, an antioxidant (BHT) is added so that 0.2 g per 100 g of the polymer, and the solvent is removed, and the amount of bound styrene (physical property 6) and the microstructure of the butadiene portion (1 ,2-vinyl bond amount: Physical property 7) was measured. Table 15 shows the measurement results.

Next, to the polymer solution subjected to the coupling reaction, an antioxidant (BHT) was continuously added at a rate of 0.055 g/min (n-hexane solution) to 0.2 g per 100 g of the polymer, and the coupling reaction was terminated.

Simultaneously with the antioxidant, as a softener for rubber, SRAE oil (JOMO Process NC140 manufactured by JX Nikko Niseki Energy Co., Ltd.) was continuously added to 25.0 g with respect to 100 g of the polymer, and mixed with a static mixer.

The solvent was removed by steam stripping, and a branched conjugated diene-based polymer (Sample A-1) having a four-branched structure derived from a branching agent in a part of the main chain and a four-branched star polymer structure derived from a coupling agent was obtained.

Table 15 shows the physical properties of Sample A-1.

In addition, for the polymer before the addition of the branching agent, the polymer after the addition of the branching agent, and the polymer in each step after the addition of the coupling agent, the molecular weight by GPC measurement and the degree of branching by GPC measurement with a viscometer by comparison of the polymer structure was identified.

(Example A-2) Branched conjugated diene-based polymer (Sample A-2)

The inner volume is 10L, the ratio (L/D) of the inner height (L) to the diameter (D) is 4.0, has an inlet at the bottom, an outlet at the top, and a stirrer, which is a tank reactor having a stirrer, and a jacket for temperature control The tank pressure vessel which had was made into a polymerization reactor, and two groups were connected.

1,3-butadiene, which had been previously dehydrated, was mixed under conditions of 14.0 g/min, styrene at 8.0 g/min, and n-hexane at 175.2 g/min. In a static mixer provided in the middle of a pipe for supplying this mixed solution to the inlet of the reactor, n-butyllithium for inert treatment of residual impurities was added and mixed at 0.103 mmol/min, and then continuously supplied to the bottom of the reactor. In addition, 2,2-bis(2-oxolanyl)propane as a polar material at a rate of 0.081 mmol/min and n-butyllithium as a polymerization initiator at a rate of 0.143 mmol/min were vigorously mixed with a stirrer. The first stage was supplied to the bottom of the reactor, and the internal temperature of the reactor was maintained at 67°C.

The polymer solution was continuously withdrawn from the top of the reactor in the first stage, continuously fed to the bottom of the reactor in the second stage to continue the reaction at 70° C., and further fed to a static mixer from the top of the second stage. In the place where polymerization is sufficiently stable, while copolymerizing 1,3-butadiene and styrene, from the bottom of the second reactor, trimethoxy(4-vinylphenyl)silane as a branching agent (in the table, “BS-1” is reduced) .) at a rate of 0.0190 mmol/min, also simultaneously adding 1,3-butadiene at 4.6 g/min and styrene at 2.0 g/min, polymerization reaction and branching to obtain a conjugated diene-based polymer having a main chain branching structure reaction was carried out.

In addition, in a place where the polymerization reaction and branching reaction are stable, a small amount of the conjugated diene-based polymer solution before addition of the coupling agent is extracted, and after adding the antioxidant (BHT) so that it becomes 0.2 g per 100 g of the polymer, the solvent is removed, and the Mooney viscosity and various molecular weights were measured. The physical properties are shown in Table 15.

Next, to the polymer solution flowing out from the outlet of the reactor, from compound A-1 as a coupling agent to compound A-9 (a compound represented by (A-9) in the <compound [A] used in the above-mentioned <denaturation step]>). In the table, it is abbreviated as "A-9".), the addition amount was continuously added at 0.0360 mmol/min, mixed using a static mixer, and coupling reaction was carried out.

At this time, the time until the coupling agent is added to the polymer solution flowing out from the outlet of the reactor is 4.8 minutes, the temperature is 68°C, and the difference between the temperature in the polymerization step and the temperature until the coupling agent is added is 2 ℃ was.

After the coupling reaction, a small amount of the conjugated diene-based polymer solution is extracted, an antioxidant (BHT) is added so that 0.2 g per 100 g of the polymer, and the solvent is removed, and the amount of bound styrene (physical property 6) and the microstructure of the butadiene portion (1 ,2-vinyl bond amount: Physical property 7) was measured. Table 15 shows the measurement results.

Next, to the polymer solution subjected to the coupling reaction, an antioxidant (BHT) was continuously added at a rate of 0.055 g/min (n-hexane solution) to 0.2 g per 100 g of the polymer, and the coupling reaction was terminated. Simultaneously with the antioxidant, as a softener for rubber, SRAE oil (JOMO Process NC140 manufactured by JX Nikko Niseki Energy Co., Ltd.) was continuously added to 25.0 g with respect to 100 g of the polymer, and mixed with a static mixer.

The solvent was removed by steam stripping to obtain a branched conjugated diene-based polymer (Sample A-2) having a four-branched structure derived from a branching agent and a four-branched star polymer structure derived from a coupling agent.

Table 15 shows the physical properties of Sample A-2.

In addition, for the polymer before the addition of the branching agent, the polymer after the addition of the branching agent, and the polymer in each step after the addition of the coupling agent, the molecular weight by GPC measurement and the degree of branching by GPC measurement with a viscometer by comparison of the polymer structure was identified.

(Comparative Example 2-1) Coupling conjugated diene-based polymer (Sample 2-24)

The inner volume is 10L, the ratio (L/D) of the inner height (L) to the diameter (D) is 4.0, has an inlet at the bottom, an outlet at the top, and a stirrer, which is a tank reactor having a stirrer, and a jacket for temperature control The tank pressure vessel which had was made into a polymerization reactor, and two groups were connected.

1,3-butadiene, which had been previously dehydrated, was mixed under the conditions of 18.6 g/min, styrene at 10.0 g/min, and n-hexane at 175.2 g/min. In a static mixer provided in the middle of a pipe for supplying this mixed solution to the inlet of the reactor, n-butyllithium for inert treatment of residual impurities was added and mixed at 0.103 mmol/min, and then continuously supplied to the bottom of the reactor. In addition, 2,2-bis(2-oxolanyl)propane as a polar material at a rate of 0.081 mmol/min and n-butyllithium as a polymerization initiator at a rate of 0.143 mmol/min were vigorously mixed with a stirrer. The first stage was supplied to the bottom of the reactor, and the internal temperature of the reactor was maintained at 67°C.

The polymer solution was continuously withdrawn from the top of the reactor in the first stage, continuously fed to the bottom of the reactor in the second stage to continue the reaction at 70° C., and further fed to a static mixer from the top of the second stage. In a place where the polymerization was sufficiently stable, a small amount of the polymer solution before the addition of the modifier was extracted, and after adding the antioxidant (BHT) to 0.2 g per 100 g of the polymer, the solvent was removed, and the Mooney viscosity and various molecular weights at 110° C. were measured. The physical properties are shown in Table 16.

Next, to the polymer solution flowing out from the outlet of the reactor, as a coupling agent, compound A-1 (a compound shown in (A-1) among the <compound [A] used in the above-mentioned <modification step]>). In the table, "A -1") was continuously added at a rate of 0.0360 mmol/min, mixed using a static mixer, and a coupling reaction was carried out.

At this time, the time until the modifier was added to the polymer solution flowing out from the outlet of the reactor was 4.8 minutes, the temperature was 68°C, and the difference between the temperature in the polymerization step and the temperature until the modifier was added was 2°C. .

After the coupling reaction, a small amount of the conjugated diene-based polymer solution is extracted, an antioxidant (BHT) is added so that 0.2 g per 100 g of the polymer, and the solvent is removed, and the amount of bound styrene (physical property 6) and the microstructure of the butadiene portion (1 ,2-vinyl bond amount: Physical property 7) was measured. Table 16 shows the measurement results.

Next, to the polymer solution subjected to the coupling reaction, an antioxidant (BHT) was continuously added at a rate of 0.055 g/min (n-hexane solution) to 0.2 g per 100 g of the polymer, and the coupling reaction was terminated. Simultaneously with the antioxidant, as a softener for rubber, SRAE oil (JOMO Process NC140 manufactured by JX Nikko Niseki Energy Co., Ltd.) was continuously added to 25.0 g with respect to 100 g of the polymer, and mixed with a static mixer. The solvent was removed by steam stripping to obtain a coupling conjugated diene-based polymer (Sample 2-24). Table 16 shows the physical properties of Sample 2-24.

(Comparative Example 2-2) Coupling conjugated diene-based polymer (Sample 2-25)

The coupling agent is compound A-1 (in the table, abbreviated as "A-1") to compound A-2 (a compound represented by (A-2) in the <compound [A] used in the above-mentioned <modification step]>; In the table, it is abbreviated as "A-2".) Except having changed to the comparative example 1, it carried out similarly to the coupling-conjugated diene type polymer (Sample 2-25).

Table 16 shows the physical properties of Samples 2-25.

(Comparative Example 2-3) Coupling conjugated diene-based polymer (Sample 2-26)

The coupling agent is compound A-1 (in the table, abbreviated as "A-1") to compound A-3 (a compound represented by (A-3) in the <compound [A] used in the above-mentioned <modification step]>; In the table, it is abbreviated as "A-3"), except that the addition amount was changed to 0.0720 mmol/min, in the same manner as in Comparative Example 2-1 to obtain a coupling conjugated diene-based polymer (Sample 2-26). .

Table 16 shows the physical properties of Sample 2-26.

(Comparative Example 2-4) Coupling conjugated diene-based polymer (Sample 2-27)

The coupling agent is changed from compound A-1 to compound A-6 (abbreviated as "A-6" in the table, the compound shown in (A-6) among the <compound [A]> used in the above-mentioned <denaturation step]>). Except having changed, it carried out similarly to Comparative Example 2-1, and obtained the coupling conjugated diene type polymer (Sample 2-27).

Table 16 shows the physical properties of Sample 2-27.

(Comparative Example 2-5) Coupling conjugated diene-based polymer (Sample 2-28)

The coupling agent is changed from compound A-1 to compound A-8 (abbreviated as "A-8" in the table, the compound shown in (A-8) in the <compound [A]> used in the above-mentioned <denaturation step>). A coupling conjugated diene-based polymer (Sample 2-28) was obtained in the same manner as in Comparative Example 2-1 except that the amount was changed to 0.0720 mmol/min.

Table 16 shows the physical properties of Sample 2-28.

(Comparative Example 2-6) Coupling conjugated diene-based polymer (Sample 2-29)

Coupling agent from compound A-1 to compound A-9 (abbreviated as "A-9" in the table, in the compound shown in (A-9) in the <compound [A]> used in the above-mentioned <denaturation step]>) Except having changed, it carried out similarly to Comparative Example 2-1, and obtained the coupling conjugated diene type polymer (Sample 2-29).

Table 16 shows the physical properties of Sample 2-29.

(Comparative Example 2-7) Coupling conjugated diene-based polymer (Sample 2-30)

The coupling agent is changed from compound A-1 to compound A-10 (in the <Compound [A]> used in the modification step, the compound shown in (A-10), in the table, it is abbreviated as “A-10”). Except having changed, it carried out similarly to Comparative Example 2-1, and obtained the coupling conjugated diene type polymer (Sample 2-30).

Table 16 shows the physical properties of Samples 2-30.

(Comparative Example 2-8) Coupling conjugated diene-based polymer (Sample 2-31)

Coupling agent from compound A-1 to compound A-12 (abbreviated as "A-12" in the table, the compound shown in (A-12) in the <compound [A]> used in the above-mentioned <denaturation step]>) A coupling conjugated diene-based polymer (Sample 2-31) was obtained in the same manner as in Comparative Example 2-1 except that the amount was changed to 0.0720 mmol/min.

Table 16 shows the physical properties of Sample 2-31.

(Comparative Example 2-9) Coupling conjugated diene-based polymer (Sample 2-32)

Coupling agent from compound A-1 to compound A-13 (abbreviated as "A-13" in the table, in the compound shown in (A-13) in the <compound [A]> used in the above-mentioned <denaturation step]>) A coupling conjugated diene-based polymer (Sample 2-32) was obtained in the same manner as in Comparative Example 2-1 except that the amount was changed to 0.0160 mmol/min.

Table 16 shows the physical properties of Sample 2-32.

(Comparative Example 2-10) Coupling conjugated diene-based polymer (Sample 2-33)

The coupling agent is changed from compound A-1 to compound A-14 (abbreviated as "A-14" in the table, the compound shown in (A-14) in the <compound [A]> used in the above-mentioned <modification step]>) A coupling conjugated diene-based polymer (Sample 2-33) was obtained in the same manner as in Comparative Example 2-1 except that the amount was changed to 0.0160 mmol/min.

Table 16 shows the physical properties of the sample 33.

(Comparative Example 2-11) Coupling conjugated diene-based polymer (Sample 2-34)

The coupling agent is changed from compound A-1 to compound A-15 (in the <Compound [A]> used in the modification step, the compound shown in (A-15), in the table, abbreviated as “A-15”). A coupling conjugated diene-based polymer (Sample 2-34) was obtained in the same manner as in Comparative Example 2-1 except that the amount was changed to 0.0360 mmol/min.

Table 16 shows the physical properties of Sample 2-34.

(Comparative Example B-1) Coupling conjugated diene polymer (Sample B-1)

The inner volume is 10L, the ratio (L/D) of the inner height (L) to the diameter (D) is 4.0, has an inlet at the bottom, an outlet at the top, and a stirrer, which is a tank reactor having a stirrer, and a jacket for temperature control The tank pressure vessel which had was made into a polymerization reactor, and two groups were connected.

1,3-butadiene, which had been previously dehydrated, was mixed under the conditions of 18.6 g/min, styrene at 10.0 g/min, and n-hexane at 175.2 g/min. In a static mixer provided in the middle of a pipe for supplying this mixed solution to the inlet of the reactor, n-butyllithium for inert treatment of residual impurities was added and mixed at 0.103 mmol/min, and then continuously supplied to the bottom of the reactor. In addition, 2,2-bis(2-oxolanyl)propane as a polar material at a rate of 0.081 mmol/min and n-butyllithium as a polymerization initiator at a rate of 0.143 mmol/min were vigorously mixed with a stirrer. The first stage was supplied to the bottom of the reactor, and the internal temperature of the reactor was maintained at 67°C.

The polymer solution was continuously withdrawn from the top of the reactor in the first stage, continuously fed to the bottom of the reactor in the second stage to continue the reaction at 70° C., and further fed to a static mixer from the top of the second stage.

In addition, in a place where the polymerization reaction is stable, a small amount of the conjugated diene-based polymer solution before addition of the coupling agent is extracted, an antioxidant (BHT) is added so that 0.2 g per 100 g of the polymer, the solvent is removed, and the Mooney viscosity of 110° C. and various The molecular weight was measured. The physical properties are shown in Table 15.

Next, trimethoxy(4-vinylphenyl)silane (abbreviated as "BS-1" in the table) was added to the polymer solution flowing out from the outlet of the reactor at a rate of 0.0190 mmol/min, and at the same time tetraethoxy Silane (in the table, abbreviated as "A") was continuously added at a rate of 0.0480 mmol/min, mixed using a static mixer, and a coupling reaction was carried out.

In Table 15, although "BS-1" of Comparative Example B-1 was described in the column of "Branching agent", since the said "BS-1" and "A" were simultaneously added, a branched main chain structure was formed could not, and did not function as a branching agent.

At this time, the time until the coupling agent is added to the polymer solution flowing out from the outlet of the reactor is 4.8 minutes, the temperature is 68°C, and the difference between the temperature in the polymerization step and the temperature until the coupling agent is added is 2 ℃ was.

After the coupling reaction, a small amount of the conjugated diene-based polymer solution is extracted, an antioxidant (BHT) is added so that 0.2 g per 100 g of the polymer, and the solvent is removed, and the amount of bound styrene (physical property 6) and the microstructure of the butadiene portion (1 ,2-vinyl bond amount: Physical property 7) was measured. Table 15 shows the measurement results.

Next, to the polymer solution subjected to the coupling reaction, an antioxidant (BHT) was continuously added at a rate of 0.055 g/min (n-hexane solution) to 0.2 g per 100 g of the polymer, and the coupling reaction was terminated.

Simultaneously with the antioxidant, as a softener for rubber, SRAE oil (JOMO Process NC140 manufactured by JX Nikko Niseki Energy Co., Ltd.) was continuously added to 25.0 g with respect to 100 g of the polymer, and mixed with a static mixer. The solvent was removed by steam stripping to obtain a coupling conjugated diene-based polymer (Sample B-1).

Table 15 shows the physical properties of Sample B-1.

In addition, for the polymer before the addition of the branching agent, the polymer after the addition of the branching agent, and the polymer in each step after the addition of the coupling agent, the molecular weight by GPC measurement and the degree of branching by GPC measurement with a viscometer by comparison of the polymer structure was identified.

(Comparative Example B-2) Coupling conjugated diene-based polymer (Sample B-2)

As a coupling agent, the coupling agent (it abbreviates to "Z-1" in a table|surface) represented by the following (Z-1) was used, and the addition amount was 0.0360 mmol/min. Other conditions were the same as in Comparative Example 2-1, to obtain a coupling conjugated diene polymer (Sample B-2) having no branching agent-derived main chain branch and having a 10-branched star polymer structure derived from a coupling agent.

Table 15 shows the physical properties of Sample B-2.

(Examples 2-24 to 2-46, Examples a-1 to 2 and Comparative Examples 2-12 to 2-22, Comparative Examples b-1 to 2)

[Rubber composition]

Samples 2-1 to 2-34, Samples A-1 to 2, and Samples B-1 to 2 shown in Tables 13 to 16 were used as raw rubber, and each raw rubber was contained according to the formulation shown below. A rubber composition was obtained.

(rubber component)

Branched conjugated diene-based polymer, coupling conjugated diene-based polymer (Samples 2-1 to 2-34, Samples A-1 to 2, Samples B-1 to 2)

: 80 parts by mass (parts by mass excluding the rubber softener)

· Hysis polybutadiene (trade name "UBEPOL BR150" manufactured by Ube Kosan Corporation)

: 20 parts by mass

(Formulation conditions)

The addition amount of each compounding agent was expressed by mass parts with respect to 100 mass parts of rubber components which do not contain the softener for rubber|gum.

· Silica 1 (trade name "Ultrasil 7000GR" manufactured by Evonik Degussa)

Nitrogen adsorption specific surface area 170 m 2 /g): 50.0 parts by mass

· Silica 2 (trade name "Zeosil Premium 200MP" manufactured by Rhodia Corporation)

Nitrogen adsorption specific surface area 220 m 2 /g): 25.0 parts by mass

・ Carbon black (trade name "Sist KH (N339)" manufactured by Tokai Carbon Corporation)

: 5.0 parts by mass

· Silane modifier (trade name "Si75" manufactured by Evonik Degussa, bis(triethoxysilylpropyl)disulfide): 6.0 parts by mass

· SRAE oil (trade name "Process NC140" manufactured by JX Nikko Niseki Energy Corporation)

: 42.0 parts by mass

(Including the amount previously added as a softener for rubber contained in Samples 2-1 to 2-34, Samples A-1 to 2, and Samples B-1 to 2)

· Zincization: 2.5 parts by mass

· Stearic acid: 1.0 part by mass

· Anti-aging agent (N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine): 2.0 parts by mass

· Sulfur: 2.2 parts by mass

Vulcanization accelerator 1 (N-cyclohexyl-2-benzothiazylsulfinamide)

: 1.7 parts by mass

Vulcanization accelerator 2 (diphenylguanidine): 2.0 parts by mass

· Total: 239.4 parts by mass

(Kneading method)

The above materials were kneaded by the following method to obtain a rubber composition. Using a closed kneader (content 0.3L) equipped with a temperature control device, the raw rubber (Samples 2-1 to 2-34) was kneaded in the first stage under the conditions of a filling rate of 65% and a rotor rotation speed of 30 to 50 rpm , Samples A-1 to 2, Samples B-1 to 2), fillers (silica 1, silica 2, carbon black), silane modifier, SRAE oil, zinc oxide and stearic acid were kneaded. At this time, the temperature of the hermetic mixer was controlled to obtain each rubber composition (formulation) at a discharge temperature of 155 to 160°C.

Then, as a second stage of kneading, the blend obtained above was cooled to room temperature, an antioxidant was added, and kneaded again to improve the dispersion of silica. Also in this case, the discharge temperature of the compound was adjusted to 155 to 160°C by temperature control of the mixer.

After cooling, as kneading in the third stage, sulfur and vulcanization accelerators 1 and 2 were added and kneaded with an open roll set at 70°C.

Then, it shape|molded and it vulcanized|vulcanized by the vulcanization press for 20 minutes at 160 degreeC.

The rubber composition before vulcanization and the rubber composition after vulcanization were evaluated. Specifically, it evaluated by the following method.

The results are shown in Tables 17 to 20.

[Evaluation of characteristics]

(Evaluation 1) formulation Mooney viscosity

After kneading in the second stage obtained above and before kneading in the third stage as a sample, using a Mooney viscometer, in accordance with ISO 289, after preheating at 130° C. for 1 minute, the rotor is rotated at 2 per minute The viscosity after rotating by rotation for 4 minutes was measured. The result of Comparative Example 2-12 was set to 100, and it was indexed. It shows that workability is so good that an index|index is small.

(Evaluation 2) Tensile strength and tensile elongation

Based on the tensile test method of JIS K6251, tensile strength and tensile elongation were measured, and the result of Comparative Example 2-12 was made into 100, and it was indexed. It shows that the tensile strength and tensile elongation (breaking strength) are so good that an index|index is large.

(Evaluation 3) Wear resistance

Using an Akron abrasion tester (manufactured by Yasuda Seiki Seisakusho Co., Ltd.), in accordance with JIS K6264-2, the amount of wear at a load of 44.4 N and 1000 rotations was measured, and the result of Comparative Example 2-12 was set to 100 and indexed. It shows that abrasion resistance is so good that an index|index is large.

(Evaluation 4) Viscoelastic parameters

Viscoelasticity parameters were measured in torsion mode using the viscoelasticity tester "ARES" manufactured by Rheometrics Scientific. Each measurement value was indexed by taking the result for the rubber composition of Comparative Example 2-12 as 100.

In 0 degreeC, tan δ measured at a frequency of 10 Hz and a strain of 1% was used as an index of wet-skid properties. It shows that wet-skid property is so good that an index|index is large.

In addition, in 50 degreeC, tan δ measured at a frequency of 10 Hz and a strain of 3% was used as an index of fuel efficiency. It shows that fuel economy saving property is so good that an index|index is small.

In addition, in 50 degreeC, the elastic modulus (G') measured at a frequency of 10 Hz and a strain of 3% was made into the parameter|index of steering stability. The larger the index, the better the steering stability.

As shown in Tables 17 to 20, Examples 2-24 to 2-46 and Examples a-1 to 2 were compared with Comparative Examples 2-12 to 2-22 and Comparative Examples b-1 to 2, It was confirmed that the mixture exhibited good processability due to low Mooney viscosity when used as a vulcanized product, excellent in abrasion resistance, handling stability and breaking strength when used as a vulcanized product, and excellent balance between low hysteresis loss and wet skid resistance.

The modified conjugated diene-based polymer obtained by the production method of the present invention has industrial applicability in fields such as tire treads, automobile interior and exterior products, vibration-proof rubber, belts, shoes, foams, and various industrial products.

Claims (20)

A polymerization step of obtaining a conjugated diene polymer having an active terminal by polymerizing or copolymerizing a conjugated diene compound or a conjugated diene compound and an aromatic vinyl compound using an alkali metal compound or an alkaline earth metal compound as a polymerization initiator;
A branching process of introducing a branched structure by reacting a styrene derivative as a branching agent to the active end of the conjugated diene-based polymer
Having, a method for producing a branched conjugated diene-based polymer. The method according to claim 1, further comprising a step of adding a conjugated diene compound and/or an aromatic vinyl compound to the reaction system during and/or after the branching step,
A method for producing a branched conjugated diene-based polymer. The reaction step according to claim 1 or 2, wherein a coupling agent or a polymerization terminator is reacted with the active terminal of the conjugated diene-based polymer obtained in the branching step.
having more,
A method for producing a branched conjugated diene-based polymer. The method for producing a branched conjugated diene-based polymer according to claim 3, wherein the coupling agent has a nitrogen atom-containing group. The method for producing a branched conjugated diene-based polymer according to claim 3, wherein the polymerization terminator has a nitrogen atom-containing group. The method for producing a branched conjugated diene-based polymer according to claim 3, wherein the polymerization terminator is an alkoxy compound having a nitrogen atom-containing group. The method for producing a branched conjugated diene-based polymer according to claim 4, wherein the coupling agent is represented by the following formula (a).

(In formula (a), R ¹ to R ⁴ each independently represent an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and R ⁵ to R ⁶ are each independently, each independently having 1 to 20 carbon atoms represents an alkylene group.
m and n are integers of 1 to 3, and in formula (a), a plurality of R ¹ to R ⁶ , m, and n may be the same or different.
In the formula (a), X is represented by any of the following general formulas (b) to (e).)

(In formula (b), R ⁷ represents a hydrocarbon group having 1 to 20 carbon atoms, and the hydrocarbon group may have a partially branched structure or a cyclic structure. R ⁸ is a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms. and may have a partially branched structure or a cyclic structure in the case of a hydrocarbon group.)

(In formula (c), R ⁹ represents a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and in the case of a hydrocarbon group, it may have a partially branched structure or a cyclic structure.)

(In formula (d), R ¹⁰ represents a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and in the case of a hydrocarbon group, it may have a partially branched structure or a cyclic structure.)

(In formula (e), R ¹¹ to R ¹⁴ each independently represents an alkylene group having 1 to 20 carbon atoms. R ¹⁵ to R ¹⁸ are each independently an alkyl group having 1 to 20 carbon atoms or an alkyl group having 6 to 20 carbon atoms. an aryl group, l and o each independently represent an integer of 1 to 3, and R ¹⁵ to R ¹⁸ in the case of two or more are each independent.) The said styrene derivative is a compound represented by following formula (1) and/or following formula (2) according to claim 1 or 2,
A method for producing a branched conjugated diene-based polymer.

(In formulas (1) and (2), R ¹ represents any selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, and an aryl group having 6 to 20 carbon atoms, and may have a branched structure in a part thereof. .
X ¹ , X ² , and X ³ are a single bond or an organic group containing any one selected from the group consisting of carbon, hydrogen, nitrogen, sulfur and oxygen.
Y ¹ , Y ² , and Y ³ represent any selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, and a halogen atom. Each is independent and may be the same or different.) The method according to claim 8, wherein in the formula (1), R ¹ is a hydrogen atom, Y ¹ is any one selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, and a halogen atom, A method for producing a branched conjugated diene-based polymer. The branched conjugated diene-based polymer according to claim 8, wherein in Formula (2), Y ² is any one selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, and a halogen atom. manufacturing method. The method for producing a branched conjugated diene-based polymer according to claim 8, wherein in the formula (1), R ¹ is a hydrogen atom and Y ¹ is an alkoxy group having 1 to 20 carbon atoms or a halogen atom. The branched conjugate according to claim 8, wherein in the formula (2), Y ² is an alkoxy group having 1 to 20 carbon atoms or a halogen atom, and Y ³ is an alkoxy group having 1 to 20 carbon atoms or a halogen atom. Method for producing a diene-based polymer. The method for producing a branched conjugated diene-based polymer according to claim 8, wherein in the formula (1), R ¹ is a hydrogen atom and Y ¹ is an alkoxy group having 1 to 20 carbon atoms. The method for producing a branched conjugated diene-based polymer according to claim 8, wherein in Formula (1), R ¹ is a hydrogen atom, X ¹ is a single bond, and Y ¹ is an alkoxy group having 1 to 20 carbon atoms. The method according to claim 8, wherein in the formula (2), X ² is a single bond, Y ² is an alkoxy group having 1 to 20 carbon atoms or a halogen atom, X ³ is a single bond, and Y ³ is a carbon number 1 to 20 alkoxy groups, or halogen atoms, a method for producing a branched conjugated diene-based polymer. A conjugated diene-based polymer having an active end having a branched structure, and
A compound represented by the following formula (a)
A branched conjugated diene polymer that is the reaction product of

(In formula (a), R ¹ to R ⁴ each independently represent an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and R ⁵ to R ⁶ are each independently, each independently having 1 to 20 carbon atoms represents an alkylene group.
m and n are integers of 1 to 3, and in formula (a), a plurality of R ¹ to R ⁶ , m, and n may be the same or different.
In the formula (a), X is represented by any of the following general formulas (b) to (e).)

(In formula (b), R ⁷ represents a hydrocarbon group having 1 to 20 carbon atoms, and the hydrocarbon group may have a partially branched structure or a cyclic structure. R ⁸ is a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms. and may have a partially branched structure or a cyclic structure in the case of a hydrocarbon group.)

(In formula (c), R ⁹ represents a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and in the case of a hydrocarbon group, it may have a partially branched structure or a cyclic structure.)

(In formula (d), R ¹⁰ represents a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and in the case of a hydrocarbon group, it may have a partially branched structure or a cyclic structure.)

(In formula (e), R ¹¹ to R ¹⁴ each independently represents an alkylene group having 1 to 20 carbon atoms. R ¹⁵ to R ¹⁸ are each independently an alkyl group having 1 to 20 carbon atoms or an alkyl group having 6 to 20 carbon atoms. an aryl group, l and o each independently represent an integer of 1 to 3, and R ¹⁵ to R ¹⁸ in the case of two or more are each independent.) The branched conjugated diene-based polymer ^{according to claim 16, wherein OR 1} and/or OR ³ of the compound represented by the formula (a) has a branched structure. A rubber component comprising 10% by mass or more of the branched conjugated diene-based polymer according to claim 16 or 17;
The rubber composition which contains 5.0 mass parts or more and 150 mass parts or less of a filler with respect to 100 mass parts of said rubber components. A step of obtaining a branched conjugated diene-based polymer by the production method according to claim 1 or 2;
A step of obtaining a rubber component containing 10% by mass or more of the branched conjugated diene-based polymer;
The process of obtaining a rubber composition by containing 5.0 mass parts or more and 150 mass parts or less of a filler with respect to 100 mass parts of said rubber components
Having, a method for producing a rubber composition. A step of obtaining a rubber composition by the method for producing the rubber composition according to claim 19;
A step of molding the rubber composition to obtain a tire
having, a method of manufacturing a tire.