JP7161883B2 - Modified conjugated diene-based polymer, method for producing the same, modified conjugated diene-based composition, and tire - Google Patents

Description

TECHNICAL FIELD The present invention relates to a modified conjugated diene polymer, a method for producing the same, a modified conjugated diene polymer composition, and a tire.

BACKGROUND ART In recent years, from the viewpoint of resource saving and environmental measures, the demand for low fuel consumption of tires has increased, and low heat generation and low fuel consumption (low hysteresis) of tires have come to be emphasized.
In order to improve low hysteresis, it is common to use a rubber composition with low heat build-up to reduce rolling resistance.
As a rubber composition that meets these demands, there is a rubber composition containing silica as a reinforcing filler, which has an excellent balance between low heat build-up and braking performance on wet roads (wet skid resistance). known as a thing.

However, silica, which has a hydrophilic surface, has the problem that in a composition obtained by blending it with a highly hydrophobic conjugated diene rubber, the particles agglomerate and the dispersibility is not good. is doing. Therefore, by introducing a functional group that interacts with the surface of silica into the conjugated diene rubber, the affinity with the surface of silica is increased, the dispersibility of silica in the rubber composition is improved, and low hysteresis is achieved. Attempts are being made to make it better.
For example, Patent Documents 1 and 2 disclose a modified conjugated diene rubber obtained by reacting an amino group-containing alkoxysilane with a polymer terminal, and a composition of the modified conjugated diene rubber and silica. ing.
Further, Patent Document 3 discloses a modified conjugated diene-based rubber obtained by initiating polymerization using a polymerization initiator containing an amino group and reacting an alkoxysilane containing an amino group with the terminal of the polymer. ing.

JP 2004-18795 A Korean Patent Publication No. 2016-0063227 U.S. Patent Application Publication No. 2016/0159957

However, a rubber material in which a functional group highly reactive with silica is introduced at the molecular end of a conjugated diene rubber undergoes a rapid reaction with silica particles during the kneading process, causing the silica particles to agglomerate to form a composition. There is a problem that the viscosity increases, the torque rises, and the extrusion workability deteriorates.
In order to solve the problem of agglomeration of silica particles caused by compounding silica in a rubber composition, the inventors of the present application have optimized the structure of the functional groups to be introduced at the molecular ends of the rubber and the total amount to be introduced. It was investigated. Then, although it is possible to improve the processability, the breaking strength of the obtained rubber composition is still insufficient, and it has been found that there is room for further improvement.

Therefore, in the present invention, in view of the above-mentioned problems of the conventional technology, a modified conjugate suitable for a fuel-saving tire composition having excellent processability, especially extrusion processability when silica is blended as a filler, and excellent breaking strength An object of the present invention is to provide a diene polymer.

As a result of intensive studies by the present inventors in order to solve the above-described problems of the prior art, the modification rate is a predetermined value or less, the weight average molecular weight is within a predetermined range, and the molecular weight distribution is within a predetermined range. As a result, the inventors have found that a modified conjugated diene-based polymer modified at both ends with a predetermined functional group can provide a composition having excellent workability and breaking strength, and have completed the present invention.
That is, the present invention is as follows.

[1]
A modification rate of 84% by mass or less, a weight average molecular weight (Mw) of 200,000 or more and 3,000,000 or less, and a molecular weight distribution (Mw/Mn) represented by the ratio of Mw to the number average molecular weight (Mn) of 1.0. 5 or more and 3.5 or less, Mooney viscosity at 110 ° C. is 105 or more,
Having a functional group represented by the following general formula (1) at the terminal, and containing an alkoxysilyl group and an amino group in a portion different from the terminal having the functional group represented by the following general formula (1) A modified conjugated diene-based polymer having a modifying group.

(In Formula (1), R ₁ and R ₂ are each independently a group consisting of an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, and an aralkyl group having 6 to 20 carbon atoms. represents at least one selected from the group consisting of a part of which may have an unsaturated bond or a branched structure, and R ₁ and R ₂ may combine to form a ring structure together with the adjacent nitrogen atoms. , R ₁ and R ₂ in that case represent an alkyl group having 5 to 12 carbon atoms.)

[2]
The modified conjugated diene-based polymer according to [1] above, represented by the following general formula (A) or (B).

(In formula (A), R ²¹ to R ²⁴ each independently represent an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and R ²⁵ and R ²⁶ each independently , represents an alkylene group having 1 to 20 carbon atoms, and R ²⁷ represents a hydrogen atom, a silyl group substituted with a hydrocarbon, an alkyl group having 1 to 20 carbon atoms, or an aryl group having 6 to 20 carbon atoms. , b, c and d are each independently integers of 1 or 2 and b and d are integers of 0 or 1, as long as (a + b) and (c + d) are each independently integers of 2 or less (Polym) represents a conjugated diene polymer, at least one end of which has a functional group represented by the general formula (1), and the functional group at the end has the following general formula (2) A functional group represented by any one of (5), wherein R ²¹ and R ²³ when there are more than one and (Polym) when there are more than one are each independent.)

(In formula (B), R ²⁸ to R ³³ each independently represent an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and R ³⁴ to R ³⁶ each independently , represents an alkylene group having 1 to 20 carbon atoms, and a, b, c, d, e, and f are (a+b), (c+d), and (e+f) each independently representing an integer of 2 or less, a, c and e each independently represent an integer of 1 or 2, b, d and f each independently represent an integer of 0 or 1. (Polym) represents a conjugated diene-based polymer, at least one terminal thereof and the terminal functional group having the functional group represented by the general formula (1) is a functional group represented by any one of the following general formulas (2) to (5). of R ²⁸ , R ³⁰ and R ³² , and plural (Polym) are each independent.)

(In formula (2), R ¹⁰ and R ¹¹ are each independently a group consisting of an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, and an aralkyl group having 6 to 20 carbon atoms. may have an unsaturated bond or a branched structure in part thereof, and R ¹⁰ and R ¹¹ may combine to form a ring structure together with the adjacent nitrogen atom. , R ¹⁰ and R ¹¹ in that case represent an alkyl group having 5 to 12 carbon atoms. )

(In formula (3), R ¹² and R ¹³ are each independently a group consisting of an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, and an aralkyl group having 6 to 20 carbon atoms. may have an unsaturated bond or a branched structure in part thereof, and R ¹² and R ¹³ may combine to form a cyclic structure together with the adjacent nitrogen atom. , R ¹² and R ¹³ in that case represent an alkyl group having 5 to 12 carbon atoms, R ¹⁴ is an alkylene group having 1 to 30 carbon atoms which may have an aliphatic or aromatic substituent, or Indicates a conjugated diene polymer having 1 to 20 carbon atoms.)

(In formula (4), R ¹⁵ and R ¹⁶ each independently consist of an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, and an aryl group having 6 to 20 carbon atoms. represents at least one selected from the group, and may partially have an unsaturated bond or a branched structure, and R ¹⁵ and R ¹⁶ may combine to form a ring structure together with the adjacent nitrogen atoms. Well, R ¹⁵ and R ¹⁶ in that case represent an alkyl group having 5 to 12 carbon atoms. )

(In formula (5), R ¹⁷ represents a hydrocarbon group having 2 to 10 carbon atoms, and may partially have an unsaturated bond or branched structure. R ¹⁸ represents a hydrocarbon group having 1 to 12 carbon atoms. and may have a branched structure in part thereof . )

[3]
The modified conjugated diene polymer according to the above [1] or [2], which contains both terminal modifying components in the range of 5% or more and 100% or less relative to the total amount of the conjugated diene polymer.
[4]
The modified conjugated diene polymer according to any one of the above [1] to [3], which contains both terminal modifying components in a range of 5% or more and 50% or less relative to the total amount of the conjugated diene polymer.
[5]
A method for producing a modified conjugated diene-based polymer according to any one of [1] to [4],
a polymerization step of obtaining a conjugated diene-based polymer by polymerizing a conjugated diene compound and an aromatic vinyl compound using an organic lithium compound having at least one nitrogen atom in the molecule as an anionic polymerization initiator;
The conjugated diene-based polymer has 4 or more alkoxy groups bonded to silyl groups in one molecule and 3
a modifying step of modifying with a modifying agent having a class amino group;
A method for producing a modified conjugated diene polymer.
[6]
In the polymerization step, an amine compound and an alkyllithium are mixed with an NH/Li molar ratio of 0.1 to 0.75 using an organolithium compound prepared as an anionic polymerization initiator to form a conjugated diene compound and an aromatic vinyl. The method for producing a modified conjugated diene-based polymer according to [5] above, wherein the compound is polymerized.
[7]
The organolithium compound is
Including an organolithium compound represented by any one of the following general formulas (6) to (9),
The method for producing the modified conjugated diene-based polymer according to [5] or [6].

(In formula (6), R ₁₀ and R ₁₁ are each independently a group consisting of an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, and an aralkyl group having 6 to 20 carbon atoms. It represents at least one selected from the above, and may have an unsaturated bond or branched structure in its part.
R ₁₀ and R ₁₁ may combine to form a ring structure together with the adjacent nitrogen atoms, in which case R ₁₀ and R ₁₁ represent an alkyl group having 5 to 12 carbon atoms. )

(In formula (7), R ₁₂ and R ₁₃ are each independently a group consisting of an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, and an aralkyl group having 6 to 20 carbon atoms. It represents at least one selected from the above, and may have an unsaturated bond or branched structure in its part.
R ₁₂ and R ₁₃ may combine to form a ring structure together with the adjacent nitrogen atoms, in which case R ₁₂ and R ₁₃ represent an alkyl group having 5 to 12 carbon atoms. R ₁₄ represents an alkylene group having 1 to 20 carbon atoms or a conjugated diene polymer having 1 to 20 carbon atoms. )

(In formula (8), R ₁₅ and R ₁₆ are each independently a group consisting of an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, and an aryl group having 6 to 20 carbon atoms. It represents at least one selected from the above, and may have an unsaturated bond or branched structure in its part.
R ₁₅ and R ₁₆ may combine to form a ring structure together with the adjacent nitrogen atoms, in which case R ₁₅ and R ₁₆ represent an alkyl group having 5 to 12 carbon atoms. )

(In formula (9), R ₁₇ represents a hydrocarbon group having 2 to 10 carbon atoms, and may partially have an unsaturated bond or a branched structure. R ₁₈ represents a hydrocarbon group having 1 to 12 carbon atoms. represents an alkyl group, and may have a branched structure in its part.)

[8]
The method for producing a modified conjugated diene-based polymer according to any one of [5] to [7], wherein in the polymerization step, the polymerization system is a continuous system and the polymerization temperature is 80° C. or higher.
[9]
In any one of [5] to [8], wherein in the modifying step, the conjugated diene-based polymer is modified with a modifying agent represented by any one of the following general formulas (10) to (12). A method for producing the modified conjugated diene-based polymer described.

(In formula (10), 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 is an alkylene group having 1 to 10 carbon atoms. R ⁶ represents an alkylene group having 1 to 20 carbon atoms, m represents an integer of 1 or 2, n represents an integer of 2 or 3, and (m+n) represents an integer of 4 or more. Each of R ¹ to R ⁴ is independent when a plurality of R 1 to R 4 are present.)

(In formula (11), 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 each independently , represents an alkylene group having 1 to 20 carbon atoms, m, n, and l each independently represents an integer of 1 to 3, and (m + n + l) represents an integer of 4 or more. R ¹ to R ⁶ are each independent.)

(In formula (12), 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 and R ⁶ each independently represents an alkylene group having 1 to 20 carbon atoms, each of m and n independently represents an integer of 1 to 3, and (m+n) represents an integer of 4 or more.
R ⁷ represents an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or a silyl group substituted with a hydrocarbon group. When a plurality of R ¹ to R ⁴ are present, they are each independent. )

[10]
100 parts by mass of a rubber component;
5.0 parts by mass or more and 150 parts by mass or less of filler;
including
The rubber component contains 10% by mass or more of the modified conjugated diene-based polymer according to any one of [1] to [4] with respect to the total amount of the rubber component.
A modified conjugated diene polymer composition.
[11]
A tire comprising the modified conjugated diene polymer composition according to [10] above.

ADVANTAGE OF THE INVENTION According to this invention, the modified conjugated diene-type polymer suitable for the composition for fuel-saving tires which is excellent in processability, especially the extrusion processability when silica is compounded, and breaking strength is obtained.

EMBODIMENT OF THE INVENTION Hereinafter, the form (henceforth "this embodiment") for implementing this invention is demonstrated in detail.
The following embodiments are examples for explaining the present invention, and are not intended to limit the present invention to the following contents. The present invention can be appropriately modified and implemented within the scope of the gist thereof.

[Modified conjugated diene-based polymer]
The modified conjugated diene-based polymer of the present embodiment has a modification rate of 84% by mass or less with respect to the total amount of the conjugated diene-based polymer, a weight average molecular weight (Mw) of 200,000 or more and 3,000,000 or less, and a molecular weight distribution (weight Average molecular weight (Mw)/number average molecular weight (Mn)) is 1.5 or more and 3.5 or less,
Having a functional group represented by the following general formula (1) at the terminal, and containing an alkoxysilyl group and an amino group at the terminal different from the terminal having the functional group represented by the following general formula (1) It has a modifying group.

An alkoxysilyl group condenses with a hydroxyl group present on the surface of silica, which is a reinforcing material, to improve the dispersibility of silica in the rubber composition, thereby improving low hysteresis. Furthermore, since the amino group has an electrostatic interaction with the hydroxyl group on the silica surface, the modified conjugated diene copolymer can be brought close to the silica surface. As a result, it is possible to create an environment in which the condensation reaction between the hydroxyl groups on the silica surface and the alkoxysilyl groups proceeds more easily, and the low hysteresis property is further improved.
In addition, since the terminal of the modified conjugated diene polymer has high mobility, the terminal of the polymer has the modifying group containing the alkoxysilyl group and the amino group, so that the hydroxyl group on the silica surface and the alkoxysilyl group becomes more accessible, and an environment in which the condensation reaction proceeds more easily can be created.

In the present specification, "having a modifying group containing an alkoxysilyl group and an amino group at the terminal" means a state in which the polymerization active terminal of the polymer is combined with a compound containing both functional groups. show.
Therefore, a plurality of polymer chains are bonded to a compound containing both functional groups to form a branched polymer, and an alkoxysilyl group and an amino group are contained in the center of the branch instead of the terminal as the polymer. It also includes the state of
Both functional groups may be directly bonded or may be bonded via an alkyl group. Although the length of the alkyl group in that case is not particularly limited, it preferably has 1 to 10 carbon atoms. By controlling the number of carbon atoms within this range, the hydroxyl groups on the silica surface and the alkoxysilyl groups are more likely to approach each other, and an environment in which the condensation reaction proceeds more easily can be created.

In formula (1), R ₁ and R ₂ are each independently selected from the group consisting of an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, and an aralkyl group having 6 to 20 carbon atoms. It represents at least one selected type and may have an unsaturated bond or a branched structure in its part.
R ₁ and R ₂ may combine to form a ring structure together with adjacent nitrogen atoms, in which case R ₁ and R ₂ represent alkyl groups having 5 to 12 carbon atoms.
When the carbon number of R ₁ and R ₂ is within the above range, it is possible to prevent the nitrogen atoms from becoming difficult to approach the silica surface due to steric hindrance, and the silica dispersibility in the rubber composition can be improved. Low hysteresis is obtained.

<Modification rate>
The modified conjugated diene-based polymer of the present embodiment has a modification rate of 84% by mass or less from the viewpoint of processability, particularly extrusion processability when silica is blended.
Modification rate means the ratio of the polymer having a functional group component (the polymer modified at least one terminal) to the total amount of the conjugated diene polymer.
The modified conjugated diene-based polymer of the present embodiment has a functional group represented by the general formula (1) at the starting terminal, and a modifying group containing an alkoxysilyl group and an amino group at a terminal different from the starting terminal. have.
The modification rate indicates the proportion of the polymer modified at least one of the starting terminal and the terminal terminal relative to the total amount of the conjugated diene-based polymer.

The functional group contained in the modifying component is not particularly limited, and is preferably a functional group that interacts with the filler surface in the rubber material.
Examples thereof include functional groups containing elements such as nitrogen, oxygen, phosphorus, and tin in their molecules. These elements may contain only 1 type, and may contain 2 or more types.

The modification rate of the modified conjugated diene-based polymer of the present embodiment can be measured by chromatography capable of separating functional group-containing modified components and non-modified components.
As a method using this chromatography, a column for gel permeation chromatography filled with a polar substance such as silica that adsorbs a specific functional group is used, and the internal standard of the non-adsorbed component is used for comparison and quantification. method.
More specifically, the modification rate by a nitrogen-containing modifier is the difference between the chromatogram of a sample solution containing a sample and a low-molecular-weight internal standard polystyrene measured with a polystyrene-based gel column and a chromatogram measured with a silica-based column. Then, the amount of adsorption to the silica column is measured. Since the amount adsorbed to the silica column corresponds to the polymer having the functional group component, the modification ratio can be obtained by measuring this ratio. More specifically, the denaturation rate can be measured by the method described in Examples.
The modified conjugated diene-based polymer of the present embodiment has a functional group represented by the general formula (1) at the starting terminal, and further contains an alkoxysilyl group and an amino group at a terminal different from the starting terminal. Although it has a modifying group, the modification rate obtained by the method described in the Examples is the ratio of the total amount of the polymer modified at either the starting end or the ending end and the polymer modified at both. show.

As a conjugated diene-based polymer for fuel-efficient tires, a modifier that imparts affinity with silica is used for the purpose of improving affinity with silica compounded in tires, so adsorption to silica columns is reduced. The method of measuring the denaturation rate used is preferably used. In the case of modifiers used for other purposes, it is assumed that they do not show affinity with silica.

The modification rate of the modified conjugated diene-based polymer of the present embodiment is 84% by mass or less, preferably 80% by mass or less, more preferably 75% by mass or less.
A modified conjugated diene-based polymer having a modification rate within this range tends to be excellent in processability, particularly in extrusion processability when silica is blended.
Methods for controlling the modification ratio to 84% by mass or less tend to be controllable by adjusting the amount of modifier added, the polymerization temperature in the polymerization step, and the preparation method of the organolithium catalyst in the polymerization step.

<Ratio of modified components at both ends>
After obtaining a conjugated diene-based polymer using an organolithium having at least one nitrogen atom in the molecule as a polymerization initiator, a modified conjugate obtained by reacting a compound containing a nitrogen atom and an alkoxysilane at the polymerization end A diene-based polymer is modified at both ends.
The ratio of modified components at both ends indicates the ratio of the components modified at both ends to the total amount of the conjugated diene polymer.
The ratio of modified components at both ends is calculated from the following formula, where A is the molar ratio of the amine compound to the alkyl lithium when preparing the polymerization initiator x 100 ((NH/Li) x 100), and R is the modification rate. can be done.
Modified components at both ends (%) = A × (100-(RA)) / (100-(RA) + 100-R)

The modified conjugated diene-based polymer of the present embodiment preferably contains both end-modified components in the range of 5% or more and 100% or less. That is, it is preferable that the both-terminal modified component ratio obtained from the above formula is 5% or more and 100% or less.
A modified conjugated diene polymer with a modified component ratio at both ends within this range has more bonding points between silica, which is a reinforcing filler in the vulcanizate, and the modified conjugated diene polymer, resulting in a stronger bond between the silica and the modified conjugated diene polymer. Since it can be formed between the conjugated diene polymer, it tends to be excellent in constant strain fatigue resistance.
Moreover, from the viewpoint of the state of the dough of the compound after kneading, the ratio of modified components at both ends is more preferably 50% or less, more preferably 20% or less. When silica and a modified conjugated diene-based polymer with an excessively high ratio of modified components at both ends in the polymer are kneaded, the crosslink density between silica and polymer becomes too high, causing shrinkage of the blend and deterioration of the fabric. If it gets worse, the processability may deteriorate. On the other hand, a modified conjugated diene-based polymer having a modified component ratio at both ends within this range makes it possible to control the crosslink density due to the bonding between the silica and the polymer after kneading with silica, resulting in shrinkage of the compound. is suppressed, and the condition of the fabric is improved.

Examples of methods for controlling the ratio of modified components at both ends include a method of adjusting the amount of modifier added, a method of adjusting the polymerization temperature in the polymerization step, and a method of adjusting the production method of the organolithium catalyst in the polymerization step.
Specifically, when the organolithium catalyst and the nitrogen atom-containing compound are mixed, increasing the ratio of the nitrogen atom-containing compound tends to increase the modification rate.
Alternatively, by separately synthesizing modified conjugated diene-based polymers having different both-terminal modified component ratios and blending the obtained polymers, it is possible to control the desired both-terminal modified component ratio.

<Weight average molecular weight>
The modified conjugated diene-based polymer of the present embodiment has a weight average molecular weight of 20×10 ⁴ or more and 300×10 ⁴ or less.
When the weight average molecular weight is 20×10 ⁴ or more, the vulcanizate tends to have excellent breaking strength. When the weight-average molecular weight is 300×10 ⁴ or less, the Mooney viscosity of the vulcanized product tends to be low and the workability tends to be excellent.
The weight average molecular weight of the modified conjugated diene polymer is preferably 50×10 ⁴ or more, more preferably 60×10 ⁴ or more. Also, the weight average molecular weight is preferably 200×10 ⁴ or less, more preferably 100×10 ⁴ or less.
The weight average molecular weight of the modified conjugated diene-based polymer and the conjugated diene-based polymer before modification described later is measured using a GPC measuring device, the chromatogram is measured with an RI detector, and the calibration curve obtained using standard polystyrene. can be measured based on Specifically, it can be measured by the method described in Examples described later.
The weight-average molecular weight of the modified conjugated diene-based polymer is controlled by the molecular weight of the conjugated diene-based polymer chain, which is controlled by the ratio between the amount of polymerization initiator used and the amount of monomer used, and the type and amount of modifier used. be able to.

<Molecular weight distribution>
The modified conjugated diene-based polymer of the present embodiment has a molecular weight distribution (Mw/Mn) of 1.5 or more and 3.5 or less from the viewpoint of breaking strength and workability when vulcanized.
The molecular weight distribution is preferably 1.7 or more and 3.3 or less, more preferably 1.8 or more and 3.0 or less.
The molecular weight distribution is controlled by the ratio of the amount of polymerization initiator used and the amount of monomer used. can be controlled to

<Preferred embodiment of modified conjugated diene-based polymer>
The modified conjugated diene-based polymer of the present embodiment is preferably a modified conjugated diene-based polymer represented by the following general formula (A) or (B). As a result, the vulcanizate has an excellent balance between low hysteresis and wet skid resistance.

In general formula (A), R ²¹ to R ²⁴ each independently represent an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and R ²⁵ and R ²⁶ each independently , represents an alkylene group having 1 to 20 carbon atoms, and R ²⁷ represents a hydrogen atom, a silyl group substituted with a hydrocarbon, an alkyl group having 1 to 20 carbon atoms, or an aryl group having 6 to 20 carbon atoms.
a, b, c and d are each independently an integer of 1 or 2 and b and d are 0 or 1, as long as (a+b) and (c+d) are each independently an integer of 2 or less. Indicates an integer.
(Polym) represents a conjugated diene-based polymer, and at least one terminal thereof represents a functional group represented by the following general formulas (2) to (5).
R ²¹ and R ²³ when there are more than one and (Polym) when there are more than one are each independently and may be the same or different.

The modified conjugated diene-based polymer of this embodiment can have a star polymer structure. As the star-shaped polymer structure, for example, in the modified conjugated diene polymer represented by the formula (A), the Si atom bonded to R ²⁵ is a branch point, and the branch point is a linear Structures bound to molecular chains (arms) R ²⁵ , (OR ²¹ ) _3-ab , R ²² _b , and (Polym) _a are exemplified.

In general formula (B), R ²⁸ to R ³³ each independently represent an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and R ³⁴ to R ³⁶ each independently , represents an alkylene group having 1 to 20 carbon atoms.
a, b, c, d, e and f are each independently 1 or 2 as long as (a+b), (c+d) and (e+f) each independently represents an integer of 2 or less and each of b, d and f independently represents an integer of 0 or 1.
(Polym) represents a conjugated diene-based polymer, and at least one terminal thereof represents a functional group represented by any one of the following general formulas (2) to (5).
R ²⁸ , R ³⁰ and R ³² when there are more than one and (Polym) when there are more than one are each independently and may be the same or different.

The modified conjugated diene-based polymer of this embodiment can have a star polymer structure.
As the star-shaped polymer structure, for example, in the modified conjugated diene-based polymer represented by the general formula (B), the Si atom bonded to R ³⁴ is a branch point, and the branch point is a linear molecule Structures bound to chains (arms) R ³⁴ , (OR ²⁸ ) _3-ab , R ²⁹ _b , and (Polym) _a are included.

In general formula (2), R ₁₀ and R ₁₁ are each independently selected from an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, an aralkyl group having 6 to 20 carbon atoms, and a protecting group. represents at least one selected from the group consisting of a portion thereof which may have an unsaturated bond or a branched bond;
R ₁₀ and R ₁₁ may combine to form a ring structure together with the adjacent nitrogen atoms, in which case R ₁₀ and R ₁₁ represent an alkyl group having 5 to 12 carbon atoms. The protective group is an alkyl-substituted silyl group.

In general formula (3), R ₁₂ and R ₁₃ are each independently selected from an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, an aralkyl group having 6 to 20 carbon atoms, and a protecting group. It may represent at least one selected from the group consisting of and partially have an unsaturated bond or a branched structure.
R ₁₂ and R ₁₃ may combine to form a ring structure together with the adjacent nitrogen atoms, in which case R ₁₂ and R ₁₃ represent an alkyl group having 5 to 12 carbon atoms.
The protective group is an alkyl-substituted silyl group.
R ₁₄ represents an alkylene group optionally having an aliphatic or aromatic substituent having 1 to 30 carbon atoms or a conjugated diene polymer having 1 to 20 carbon atoms.

In general formula (4), R ₁₅ and R ₁₆ are each independently selected from an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, an aryl group having 6 to 20 carbon atoms, and a protecting group. It may represent at least one selected from the group consisting of and partially have an unsaturated bond or a branched structure.
R ₁₅ and R ₁₆ may combine to form a ring structure together with the adjacent nitrogen atoms, in which case R ₁₅ and R ₁₆ represent an alkyl group having 5 to 12 carbon atoms. The protective group is an alkyl-substituted silyl group.

In general formula (5), R ₁₇ represents a hydrocarbon group having 2 to 10 carbon atoms, which may partially have an unsaturated bond or a branched structure.
R ₁₈ represents an alkyl group having 1 to 12 carbon atoms or a protective group, and may partially have a branched structure. The protective group is an alkyl-substituted silyl group.

In general formula (A), R ²¹ to R ²⁴ preferably each independently represent an alkyl group having 1 to 8 carbon atoms, more preferably an alkyl group having 1 to 4 carbon atoms.
Each of R ²⁵ and R ²⁶ independently represents preferably an alkylene group having 1 to 8 carbon atoms, more preferably an alkylene group having 2 to 4 carbon atoms.
R ²⁷ preferably represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, more preferably a hydrogen atom.
Further, the groups represented by R ²¹ to R ²⁴ are not limited to the following, but examples thereof include methyl group, ethyl group, propyl group, butyl group and isobutyl group, preferably methyl group and ethyl group. .
Examples of R ²⁵ and R ²⁶ include methylene group, ethylene group, propylene group, butylene group and pentylene group, preferably ethylene group, propylene group and butylene group.
R ²⁷ represents a hydrogen atom, a methyl group, an ethyl group, a propyl group, a butyl group and an isobutyl group, preferably a hydrogen atom, a methyl group and an ethyl group.
In general formula (A), the number average molecular weight of (Polym) is not particularly limited, but is preferably 250,000 or more and 1,500,000 or less, more preferably 350,000 or more and 900,000 or less. preferable.

In general formula (B), R ²⁸ to R ³³ preferably each independently represent an alkyl group having 1 to 8 carbon atoms, more preferably an alkyl group having 1 to 4 carbon atoms.
R ³⁴ and R ³⁵ each independently preferably represents an alkylene group having 1 to 8 carbon atoms, more preferably an alkylene group having 2 to 4 carbon atoms.
Examples of groups represented by R ²⁸ to R ³³ include methyl group, ethyl group, propyl group, butyl group and isobutyl group, preferably methyl group and ethyl group.
Examples of groups represented by R ³⁴ to R ³⁶ include methylene group, ethylene group, propylene group, butylene group and pentylene group, preferably ethylene group, propylene group and butylene group.
In general formula (B), the number average molecular weight of (Polym) is not particularly limited, but is preferably 250,000 or more and 1,500,000 or less, more preferably 350,000 or more and 900,000 or less. preferable.

In formula (2), when R ₁₀ and R ₁₁ represent alkyl groups, R ¹⁰ and R ₁₁ preferably represent C 1-6 alkyl groups.
When R ₁₀ and R ₁₁ represent a cycloalkyl group, R ₁₀ and R ₁₁ preferably represent a cycloalkyl group having 5 to 7 carbon atoms.
When R ₁₀ and R ₁₁ represent an aralkyl group, R ₁₀ and R ₁₁ preferably represent an aralkyl group having 6 to 8 carbon atoms.
When R ₁₀ and R ₁₁ combine to form a cyclic structure together with adjacent nitrogen atoms, R ₁₀ and R ₁₁ preferably represent an alkyl group having 5 to 7 carbon atoms.
Examples of R ₁₀ and R ₁₁ are not limited to the following, but include, for example, methyl group, ethyl group, propyl group, butyl group and isobutyl group, preferably butyl group and isobutyl group. .
When R ₁₀ and R ₁₁ are bonded together to form a cyclic structure together with the adjacent nitrogen atoms, the representations of R ₁₀ and R ₁₁ are not limited to the following, but examples include methylene group, ethylene group, propylene group, butylene group, pentylene group and hexylene group, preferably butylene group, pentylene group and hexylene group.

In general formula (3), R ₁₂ and R ₁₃ may combine to form a cyclic structure together with the adjacent nitrogen atoms, in which case R ₁₂ and R ₁₃ are C 5-12 alkyl groups indicates
Further, the groups represented by R ₁₂ and R ₁₃ are not limited to the following, and examples thereof include methyl group, ethyl group, propyl group, butyl group and isobutyl group, preferably butyl group and isobutyl group. be.
When R ₁₂ and R ₁₃ are combined to form a cyclic structure together with the adjacent nitrogen atoms, what R ₁₂ and R ₁₃ represent is not limited to the following, but examples include methylene group, ethylene group, propylene group, butylene group, pentylene group and hexylene group, preferably butylene group, pentylene group and hexylene group.
In general formula (3), R ₁₄ preferably represents an alkylene group having 1 to 8 carbon atoms. Examples of R ₁₄ include, but are not limited to, methylene group, ethylene group, propylene group, butylene group, pentylene group and hexylene group, preferably ethylene group and propylene group. , is a butylene group.

In general formula (4), R ₁₅ and R ₁₆ represent, but are not limited to, methyl, ethyl, propyl, butyl and isobutyl groups, preferably methyl group, ethyl group.

In general formula (5), R ₁₇ preferably represents an alkyl group having a total of 4-6 carbon atoms.
R ₁₈ preferably represents an alkyl group having 1 to 4 carbon atoms.
Examples of groups represented by R ₁₇ include, but are not limited to, butylene, pentylene and hexylene groups, preferably pentylene and hexylene groups.
Examples of what R ₁₈ represents include, but are not limited to, methyl group, ethyl group, propyl group, butyl group and isobutyl group, preferably methyl group and ethyl group.

[Method for producing modified conjugated diene-based polymer]
As a method for producing the modified conjugated diene-based polymer of the present embodiment, an organic lithium compound having at least one nitrogen atom in the molecule is used as an anionic polymerization initiator, at least a conjugated diene compound, and if necessary, other monomers. a polymerization step of polymerizing a monomer to obtain a conjugated diene-based polymer; and a denaturing step of denaturing.
The conjugated diene-based polymer constituting the modified conjugated diene-based polymer is a homopolymer of a single conjugated diene compound, a polymer of different types of conjugated diene compounds, that is, a copolymer, or a conjugated diene compound and an aromatic vinyl compound. It is a copolymer with

(Polymerization process)
In the polymerization step, it is preferable to use an organic lithium compound having at least one nitrogen atom in the molecule as the polymerization initiator.

<Polymerization initiator>
As the polymerization initiator, a polymerization initiator system containing an organic lithium compound can be used.
The polymerization initiator system preferably has at least one nitrogen atom in the molecule from the viewpoint of excellent low hysteresis loss property when vulcanized.
In the polymerization initiator system, an organic lithium compound having at least one nitrogen atom in the molecule may be prepared in advance in a predetermined reactor, or may be added in a reactor for performing polymerization or copolymerization described later. The organic lithium may be reacted with a compound having at least one nitrogen atom in the molecule at the same time as or before the polymerization or copolymerization.

As compounds having at least one nitrogen atom in the molecule, compounds represented by the following general formulas (13) to (15) can be used.
These compounds are reactive with organolithium compounds, and the obtained organolithium compounds can be used in polymerization initiator systems for anionic polymerization.
In addition, by having at least one nitrogen atom in the molecule, it is possible to fix the end of the polymer to silica by interacting the nitrogen atom with silica as a reinforcing material when vulcanized, which is excellent. A low hysteresis loss property can be obtained.

In general formula (13), R ₁₀ and R ₁₁ each independently represent a group consisting of an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, and an aralkyl group having 6 to 20 carbon atoms. It represents at least one selected from the above, and may have an unsaturated bond or branched structure in its part.
R ₁₀ and R ₁₁ may combine to form a ring structure together with the adjacent nitrogen atoms, in which case R ₁₀ and R ₁₁ represent an alkyl group having 5 to 12 carbon atoms.

In general formula (14), R ₁₂ and R ₁₃ each independently represent a group consisting of an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, and an aralkyl group having 6 to 20 carbon atoms. It represents at least one selected from the above, and may have an unsaturated bond or branched structure in its part.
R ₁₂ and R ₁₃ may combine to form a ring structure together with the adjacent nitrogen atoms, in which case R ₁₂ and R ₁₃ represent an alkyl group having 5 to 12 carbon atoms.
R ₁₄ represents an alkylene group having 1 to 20 carbon atoms or a conjugated diene polymer having 1 to 20 carbon atoms.
X represents a Cl atom, Br atom, I atom, or hydrogen atom.

In general formula (15), R ₁₅ and R ₁₆ are each independently a group consisting of an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, and an aryl group having 6 to 20 carbon atoms. It represents at least one selected from the above, and may have an unsaturated bond or branched structure in its part.
R ₁₅ and R ₁₆ may combine to form a ring structure together with the adjacent nitrogen atoms, in which case R ₁₅ and R ₁₆ represent an alkyl group having 5 to 12 carbon atoms.

In general formula (13), R ₁₀ and R ₁₁ represent, but are not limited to, the following, for example, methyl group, ethyl group, propyl group, butyl group, octyl group, cyclopropyl group, cyclohexyl group, 3-phenyl-1-propyl group, isobutyl group, decyl group, heptyl group and phenyl group.
Examples of the compound represented by formula (13) include, but are not limited to, dimethylamine, diethylamine, dibutylamine, dipropylamine, diheptylamine, dihexylamine, dioctylamine, di-2- Ethylhexylamine, didecylamine, ethylpropylamine, ethylbutylamine, ethylbenzylamine, methylphenethylamine and the like.
The compounds represented by the general formula (13) are not limited to these, and analogues thereof are included as long as R ₁₀ and R ₁₁ satisfy the above conditions.
The compound represented by the general formula (13) reduces the hysteresis loss of the modified conjugated diene-based polymer composition of the present embodiment, which will be described later, from the viewpoint of reducing the unpleasant odor of the modified conjugated diene-based polymer of the present embodiment, and From the viewpoint of chain transfer reaction control, which will be described later, dibutylamine and dihexylamine are preferred, and dibutylamine is more preferred.
When R ₁₀ and R ₁₁ combine to form a cyclic structure together with the adjacent nitrogen atoms, the compound represented by general formula (13) includes, for example, piperidine, hexamethyleneimine, azacyclooctane, 1 , 3,3-trimethyl-6-azabicyclo[3.2.1]octane, 1,2,3,6-tetrahydropyridine.
The compounds represented by the general formula (13) are not limited to these, and analogues thereof are included as long as the above conditions are satisfied.
The compound represented by the general formula (13) reduces the hysteresis loss of the modified conjugated diene-based polymer composition of the present embodiment, which will be described later, from the viewpoint of reducing the unpleasant odor of the modified conjugated diene-based polymer of the present embodiment, and From the viewpoint of chain transfer reaction control described later, piperidine, hexamethyleneimine, azacyclooctane, 1,3,3-trimethyl-6-azabicyclo[3.2.1]octane are preferred, more preferably piperidine and hexamethyleneimine. and more preferably piperidine.

In the general formula (14), from the viewpoint of reactivity and interaction with inorganic fillers such as carbon and silica, R ₁₄ preferably represents an alkyl group having 2 to 16 carbon atoms, more preferably It is to represent 3 to 10 alkyl groups.
Examples of the compound represented by the general formula (14) include, but are not limited to, 3-chloro-dimethylpropan-1-amine, 3-chloro-diethylpropan-1-amine, 3-chloro-dibutylpropane- 1-amine, 3-chloro-dipropylpropan-1-amine, 3-chloro-diheptylpropan-1-amine, 3-chloro-dihexylpropan-1-amine, 3-chloropropyl-ethylhexane-1-amine Amine, 3-chloro-didecylpropan-1-amine, 3-chloro-ethylpropan-1-amine, 3-chloro-ethylbutan-1-amine, 3-chloro-ethylpropan-1-amine, benzyl-3- Chloro-ethylpropan-1-amine, 3-chloro-ethylphenethylpropan-1-amine, 3-chloro-methylphenethylpropan-1-amine, 1-(3-chloropropyl)piperidine, 1-(3-chloropropyl ) hexamethyleneimine, 1-(3-chloropropyl)azacyclooctane, 6-(3-chloropropyl)-1,3,3-trimethyl-6-azabicyclo[3.2.1]octane, 1-(3 -chloropropyl)-1,2,3,6-tetrahydropyridine, 1-(3-bromopropyl)hexamethyleneimine, 1-(3-iodopropyl)hexamethyleneimine, 1-(3-chlorobutyl)hexamethyleneimine , 1-(3-chloropentyl)hexamethyleneimine, 1-(3-chlorohexyl)hexamethyleneimine, and 1-(3-chlorodecyl)hexamethyleneimine.
The compounds represented by the general formula (14) are not limited to these, and analogues thereof are included as long as the above conditions are satisfied.
From the viewpoint of reactivity and interaction with inorganic fillers such as carbon and silica, the compound represented by the general formula (14) is 3-chloro-dibutylpropan-1-amine, 1-(3-chloropropyl ) hexamethyleneimine, more preferably 1-(3-chloropropyl)hexamethyleneimine.

In general formula (14), when R ₁₄ represents a conjugated diene-based polymer having any one repeating unit of the following formulas (16) to (18), X represents a hydrogen atom.

When X represents a hydrogen atom, the compound represented by the general formula (14) is not limited to the following, but examples include N,N-dimethyl-2-butenyl-1-amine, N,N-diethyl -2-butenyl-1-amine, N,N-dibutyl-2-butenyl-1-amine, N,N-dipropyl-2-butenyl-1-amine, N,N-diheptyl-2-butenyl-1 -amine, N,N-dihexyl-2-butenyl-1-amine, N,N-dioctyl-2-butenyl-1-amine, N,N-(di-2-ethylhexyl)-2-butenyl -1-amine, N,N-didecyl-2-butenyl-1-amine, N,N-ethylpropyl-2-butenyl-1-amine, N,N-ethylbutyl-2-butenyl-1-amine, N, N-ethylbenzyl-2-butenyl-1-amine, N,N-methylphenethyl-2-butenyl-1-amine, N,N-dimethyl-2-methyl-2-butenyl-1-amine, N,N- diethyl-2-methyl-2-butenyl-1-amine, N,N-dibutyl-2-methyl-2-butenyl-1-amine, N,N-dipropyl-2-methyl-2-butenyl-1-amine, (N,N-diheptyl-2-methyl-2-butenyl-1-amine, N,N-dihexyl-2-methyl-2-butenyl-1-amine, N,N-dimethyl-3-methyl -2-butenyl-1-amine, N,N-diethyl-3-methyl-2-butenyl-1-amine, N,N-dibutyl-3-methyl-2-butenyl-1-amine, N,N-dipropyl -3-methyl-2-butenyl-1-amine, N,N-diheptyl-3-methyl-2-butenyl-1-amine, N,N-dihexyl-3-methyl-2-butenyl-1 -amine, 1-(2-butenyl)piperidine, 1-(2-butenyl)hexamethyleneimine, 1-(2-butenyl)azacyclooctane, 6-(2-butenyl)1,3,3-trimethyl-6 -azabicyclo[3.2.1]octane, 1-(2-butenyl)-1,2,3,6-tetrahydropyridine, (2-methyl-2-butenyl)hexamethyleneimine, (3-methyl-2- butenyl)hexamethyleneimine.
The compounds represented by the general formula (14) are not limited to these, and analogues thereof are included as long as the above conditions are satisfied.
From the viewpoint of reducing the hysteresis loss of the modified conjugated diene polymer composition of the present embodiment described later, the compound represented by the general formula (14) is N,N-dibutyl-2-butenyl 1-amine, 1-( 2-butenyl)hexamethyleneimine is preferred, more preferably 1-(2-butenyl)piperidine, 1-(2-butenyl)hexamethyleneimine, and still more preferably 1-(2-butenyl)piperidine.

In the polymerization initiator, the compound represented by the general formula (15) is not limited to the following, but examples include N,N-dimethyl-o-toluidine, N,N-dimethyl-m-toluidine, N, N-dimethyl-p-toluidine, N,N-diethyl-o-toluidine, N,N-diethyl-m-toluidine, N,N-diethyl-p-toluidine, N,N-dipropyl-o-toluidine, N, N-dipropyl-m-toluidine, N,N-dipropyl-p-toluidine, N,N-dibutyl-o-toluidine, N,N-dibutyl-m-toluidine, N,N-dibutyl-p-toluidine, o- piperidinotoluene, p-piperidinotoluene, o-pyrrolidinotoluene, p-pyrrolidinotoluene, N,N,N',N'-tetramethyltoluylenediamine, N,N,N',N'- Tetraethyltoluylenediamine, N,N,N',N'-tetrapropyltoluylenediamine, N,N-dimethylxylidine, N,N-diethylxylidine, N,N-dipropylxylidine, N,N- Dimethylmethidine, N,N-diethylmethidine, (N,N-dimethylamino)toluylphenylmethylamine, 1-(N,N-dimethylamino)-2-methylnaphthalene, 1-(N,N-dimethylamino )-2-methylanthracene.
The compounds represented by the general formula (15) are not limited to these, and analogues thereof are included as long as the above conditions are satisfied.
The compound represented by the general formula (15) is preferably N,N-dimethyl-o-toluidine from the viewpoint of reducing the hysteresis loss of the modified conjugated diene polymer composition described later.

Examples of organic lithium compounds used as polymerization initiators include, but are not limited to, n-butyllithium, sec-butyllithium, tert-butyllithium, n-propyllithium and iso-propyllithium.
The organic lithium compound used as the polymerization initiator preferably has at least one nitrogen atom in the molecule and can be used as a polymerization initiator for anionic polymerization, from the viewpoint of improving the modification rate and improving fuel efficiency. , preferably contains an organolithium compound represented by any one of the following general formulas (6) to (9).

In order to make the modification rate of the modified conjugated diene-based polymer of the present embodiment 84% by mass or less, the organolithium compound as the polymerization initiator contains an amine compound and an alkyllithium in an NH/Li molar ratio of 0.1 to 0. It is preferred to use one prepared at 0.75.

With respect to the denaturation rate, a molecular chain that is denatured at either the start end or the end end is defined as denatured.
Assuming the process of polymerizing a conjugated diene polymer by lithium anion polymerization, there is no change in the modification rate whether or not the molecular chain having a functional group at the start end is bound to the modifier at the end end. If a molecular chain having no functional group at its end is bound to the modifier at the terminal end, the modification rate increases.
Since it is not possible to control which of the molecular chains having a functional group at the starting end and the molecular chain not having a functional group binds to the modifying agent at the end end side, the modification rate is set to 84% by mass or less. , the target denaturation rate is set at the start end and the end end. Therefore, assuming that both the starting end and the ending end are denatured, the modification rate of the starting end is set lower than the upper limit of the overall modification rate of 84% by mass. Specifically, the starting terminal modification rate is preferably 70% by mass or less, and more preferably 50% by mass or less, assuming that the modification rate on the terminal terminal side is increased to some extent.
For example, when the polymerization initiator is prepared with dimethylamine and n-butyllithium, if the molar ratio of dimethylamine/n-butyllithium is 0.6, about 60% of the resulting polymer has a modified starting end. and 40% will not be denatured.
Thus, the NH/Li ratio of the polymerization initiator influences the initiation terminal modification rate.
The NH/Li molar ratio is preferably 0.7 or less in order to make the starting terminal modification rate 70% by mass or less, and it is preferably 0.5 or less in order to make the starting terminal modification rate 50% by mass or less. A preferable lower limit of the starting terminal modification rate is 5% by mass, and in order to achieve this, it is preferable to set the NH/Li ratio to 0.05 or more.
When the starting terminal side is modified with an amino group, the terminal terminal side is modified with a modifying agent containing an alkoxysilyl group and an amino group.
Although the lower limit of the modification rate by the modifying agent containing an alkoxysilyl group and an amino group is not limited, it is preferably 30% by mass or more, more preferably 35% by mass or more, from the viewpoint of fuel efficiency. Although it depends on the modification rate on the starting end side, in order to make the overall modification rate 84% by mass or less, the amount of modifier added is such that the (target) modification rate on the ending terminal side is 80% by mass or less. is preferably set, and is more preferably 70% by mass or less.

In general formula (6), R ₁₀ and R ₁₁ are each independently selected from the group consisting of an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, and an aralkyl group having 6 to 20 carbon atoms. It represents at least one selected type and may have an unsaturated bond or a branched bond in its part.
R ₁₀ and R ₁₁ may combine to form a ring structure together with the adjacent nitrogen atoms, in which case R ₁₀ and R ₁₁ represent an alkyl group having 5 to 12 carbon atoms.

In general formula (7), R ₁₂ and R ₁₃ are each independently selected from the group consisting of an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, and an aralkyl group having 6 to 20 carbon atoms. It represents at least one selected type and may have an unsaturated bond or a branched structure in its part.
R ₁₂ and R ₁₃ may combine to form a ring structure together with the adjacent nitrogen atoms, in which case R ₁₂ and R ₁₃ represent an alkyl group having 5 to 12 carbon atoms.
R ₁₄ represents an alkylene group having 1 to 20 carbon atoms or a conjugated diene polymer having 1 to 20 carbon atoms.

In general formula (8), R ₁₅ and R ₁₆ are each independently selected from the group consisting of an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, and an aryl group having 6 to 20 carbon atoms. It represents at least one selected type and may have an unsaturated bond or a branched structure in its part.
R ₁₅ and R ₁₆ may combine to form a ring structure together with the adjacent nitrogen atoms, in which case R ₁₅ and R ₁₆ represent an alkyl group having 5 to 12 carbon atoms.

In general formula (9), R ₁₇ represents a hydrocarbon group having 2 to 10 carbon atoms, which may partially have an unsaturated bond or a branched structure. R ₁₈ represents an alkyl group having 1 to 12 carbon atoms and may partially have a branched structure.

Examples of R ¹⁰ and R ¹¹ in general formula (6) include methyl group, ethyl group, propyl group, butyl group, octyl group, sililithium group, ethylpropylaminolithium group, ethylbutylaminolithium group, Examples include an ethylbenzylaminolithium group and a methylphenethylaminolithium group.
R ¹⁰ and R ¹¹ are not limited to these, and include analogues thereof provided that the above conditions are satisfied.
A dibutylaminolithium group and a dihexylaminolithium group are preferable from the viewpoints of solubility in a solvent, reduction of hysteresis loss of the modified conjugated diene polymer composition of the present embodiment described later, and chain transfer reaction control described later. , and more preferably a dibutylamine group.
In general formula (6), when R ₁₀ and R ₁₁ are combined to form a cyclic structure together with the adjacent nitrogen atoms, the organic lithium compound represented by general formula (12) is not limited to the following: are, for example, piperidinolithium, hexamethyleneiminolithium, lithium azacyclooctane, lithium-1,3,3-trimethyl-6-azabicyclo[3.2.1]octane, 1,2,3,6-tetrahydro and pyridinolithium.
Organolithium compounds include, but are not limited to, analogues thereof provided that the above conditions are met. From the viewpoint of the solubility of the polymerization initiator in the solvent, the reduction of the unpleasant odor of the modified conjugated diene-based polymer of the present embodiment, and the suppression of the chain transfer reaction, piperidinolithium, hexamethyleneiminolithium, lithium azacyclo Octane, lithium-1,3,3-trimethyl-6-azabicyclo[3.2.1]octane is preferred, piperidinolithium or hexamethyleneiminolithium is more preferred, and piperidinolithium is even more preferred. .

In general formula (7), R ₁₄ represents an alkylene group having 1 to 20 carbon atoms or a conjugated diene polymer having 1 to 20 carbon atoms.
The conjugated diene-based polymer is preferably a conjugated diene-based polymer having a repeating unit represented by any one of the following formulas (16) to (18).

In the general formula (7), when R ₁₄ represents an alkylene group having 1 to 20 carbon atoms, from the viewpoint of reactivity and interaction with inorganic fillers such as carbon and silica, R ₁₄ has 2 to 2 carbon atoms. An alkylene group having 16 carbon atoms is preferred, and an alkylene group having 3 to 10 carbon atoms is more preferred.
Further, when R ₁₄ represents an alkylene group having 1 to 20 carbon atoms, the organolithium compound represented by formula (7) is not limited to the following, but for example, (3-(dimethylamino)-propyl)lithium , (3-(diethylamino)-propyl)lithium, (3-(dipropylamino)-propyl)lithium, (3-(dibutylamino)-propyl)lithium, (3-(dipentylamino)-propyl)lithium, ( 3-(dihexylamino)-propyl)lithium, (3-(dioctylamino)-propyl)lithium, (3-(ethylhexylamino)-propyl)lithium, (3-(didecylamino)-propyl)lithium, (3- (Ethylpropylamino-propyl)lithium, (3-(ethylbutylamino-propyl)lithium, (3-(ethylbenzylamino)-propyl)lithium, (3-(methylphenethylamino)-propyl)lithium, (4- (Dibutylamino)-butyl)lithium, (5-(dibutylamino)-pentyl)lithium, (6-(dibutylamino)-hexyl)lithium, (10-(dibutylamino)-decyl)lithium.
Organolithium compounds include, but are not limited to, analogues thereof provided that the above conditions are met. From the viewpoint of reactivity and interaction with inorganic fillers such as carbon and silica, (3-(dibutylamino)-propyl)lithium is more preferred.

In the general formula (7), when R ₁₄ represents a conjugated diene-based polymer having repeating units represented by the above formulas (16) to (18), the organolithium compound represented by the general formula (7) is , for example but not limited to (4-(dimethylamino)-2-butenyl)lithium, (4-(diethylamino)-2-butenyl)lithium, (4-(dibutylamino)-2-butenyl)lithium, (4-(dipropylamino)-2-butenyl)lithium, (4-(diheptylamino)-2-butenyl)lithium, (4-(dihexylamino)-2-butenyl)lithium, (4-(dioctyl) amino)-2-butenyl)lithium, (4-(di-2-ethylhexylamino)-2-butenyl)lithium, (4-(didecylamino)-2-butenyl)lithium, (4-(ethylpropylamino)- 2-butenyl)lithium, (4-(ethylbutylamino)-2-butenyl)lithium, (4-(ethylbenzylamino)-2-butenyl)lithium, (4-(methylphenethylamino)-2-butenyl)lithium , (4-(dimethylamino)-2-methyl-2-butenyl)lithium, (4-(diethylamino)-2-methyl-2-butenyl)lithium, (4-(dibutylamino)-2-methyl-2- butenyl)lithium, (4-(dipropylamino)-2-methyl-2-butenyl)lithium, (4-(diheptylamino)-2-methyl-2-butenyl)lithium, (4-(dihexylamino) -2-methyl-2-butenyl)lithium, (4-(dimethylamino)-3-methyl-2-butenyl)lithium, (4-(diethylamino)-3-methyl-2-butenyl)lithium, (4-( Dibutylamino)-3-methyl-2-butenyl)lithium, (4-(dipropylamino)-3-methyl-2-butenyl)lithium, (4-(diheptylamino)-3-methyl-2-butenyl) lithium, (4-(dihexylamino)-3-methyl-2-butenyl)lithium;
Organolithium compounds include, but are not limited to, analogues thereof provided that the above conditions are met. From the viewpoint of reactivity as a polymerization initiator and from the viewpoint of chain transfer reaction control described later, 4-(dimethylamino)-2-butenyl)lithium, (4-(diethylamino)-2-butenyl)lithium, (4- (Dibutylamino)-2-butenyl)lithium is preferred, and (4-(dibutylamino)-2-butenyl)lithium is more preferred.

In the general formula (7), when R ₁₂ and R ₁₃ are combined to form a cyclic structure together with the adjacent nitrogen atoms, the organolithium compound represented by the general formula (7) includes, for example, (3 -(piperidinyl)propyl)lithium, (3-(hexamethineleniminyl)propyl)lithium, (3-(heptamethyleneiminyl)propyl)lithium, (3-(octamethyleneiminyl)propyl)lithium, (3 -(1,3,3-trimethyl-6-azabicyclo[3.2.1]octanyl)propyl)lithium, (3-(1,2,3,6-tetrahydropyridinyl)propyl)lithium, (2- (Hexamethineleniminyl)ethyl)lithium, (4-(hexamethineleniminyl)butyl)lithium, (5-(hexamethineleniminyl)pentyl)lithium, (6-(hexamethineleniminyl)hexyl ) lithium, (10-(hexamethineleniminyl)decyl)lithium, (4-(piperidinyl)-2-butenyl)lithium, (4-(hexamethineleniminyl)-2-butenyl)lithium, (4- (heptamethyleneiminyl)-2-butenyl)lithium, (4-(octamethyleneiminyl)-2-butenyl)lithium, (4-(1,3,3-trimethyl-6-azabicyclo[3.2.1 ] Octanyl)-2-butenyl)lithium, (4-(1,2,3,6-tetrahydropyridinyl)-2-butenyl)lithium, (4-(hexamethineleniminyl)-2-methyl-2 -butenyl)lithium, (4-(hexamethineleniminyl)-3-methyl-2-butenyl)lithium.
Organolithium compounds include, but are not limited to, analogues thereof provided that the above conditions are met. From the viewpoint of reactivity and interaction with inorganic fillers such as carbon and silica, and from the viewpoint of chain transfer reaction control described later, (3-(piperidinyl)propyl)lithium, (3-(hexamethineleniminyl)propyl ) lithium, (3-(1,2,3,6-tetrahydropyridinyl)propyl)lithium, (4-(piperidinyl)-2-butenyl)lithium, (4-(hexamethineleniminyl)-2- butenyl)lithium is preferred, more preferably (3-(hexamethineleniminyl)propyl)lithium, (4-(piperidinyl)-2-butenyl)lithium, (4-(hexamethineleniminyl)-2-butenyl ) lithium, more preferably (4-(piperidinyl)-2-butenyl)lithium.

Examples of the organic lithium compound represented by the general formula (8) include, but are not limited to, N,N-dimethyl-o-toluidinolithium, N,N-dimethyl-m-toluidinolithium, N , N-dimethyl-p-toluidinolithium, N,N-diethyl-o-toluidinolithium, N,N-diethyl-m-toluidinolithium, N,N-diethyl-p-toluidinolithium , N,N-dipropyl-o-toluidinolithium, N,N-dipropyl-m-toluidinolithium, N,N-dipropyl-p-toluidinolithium, N,N-dibutyl-o-toluidinium Nolithium, N,N-dibutyl-m-toluidinolithium, N,N-dibutyl-p-toluidinolithium, o-piperidinotoluenolithium, p-piperidinotoluenolithium, o-pyrrolidinolithium enolithium, p-pyrrolidinotoluene, N,N,N',N'-tetramethyltoluylenediaminolithium, N,N,N',N'-tetraethyltoluylenediaminolithium, N,N,N',N ′-tetrapropyltoluylenediaminolithium, N,N-dimethylxyridinolithium, N,N-diethylxyridinolithium, N,N-dipropylxyridinolithium, N,N-dimethylmesidinolithium, N,N- Diethylmesidinolithium, (N,N-dimethylamino)toluylphenylmethylaminolithium, 1-(N,N-dimethylamino)-2-methylnaphthalenolithium, 1-(N,N-dimethylamino)-2- and methylanthracenolithium.
Organolithium compounds include, but are not limited to, analogues thereof provided that the above conditions are met. From the viewpoint of polymerization activity, N,N-dimethyl-o-toluidinolithium is more preferable.

Examples of the organic lithium compound represented by the general formula (9) include, but are not limited to, 2-(2-methylpiperidinyl)-1-ethyllithium (for example, trade name "AI- 250").
Organolithium compounds include, but are not limited to, analogues thereof provided that the above conditions are met.

An organolithium compound having at least one nitrogen atom in the molecule may be prepared in advance before the polymerization step, and any known method can be employed for the preparation.

The organic lithium compound having at least one nitrogen atom in the molecule represented by the general formula (6) is obtained by, for example, reacting the compound represented by the formula (13) with the organic lithium compound in a hydrocarbon solvent. obtained by
As the hydrocarbon solvent, an appropriate solvent such as hexane, cyclohexane, benzene, etc. may be selected. Although the polymerization temperature is not particularly limited, it is preferably 80° C. or higher, more preferably 82° C. or higher, and even more preferably 85° C. or higher from the viewpoint of productivity. Moreover, from the viewpoint of the denaturation rate, the temperature is preferably 95°C or less.

Organolithium compounds having at least one nitrogen atom in the molecule represented by the general formula (7) are represented by, for example, the formula (14) when R ₁₄ represents an alkylene group having 1 to 20 carbon atoms. A compound and an organic lithium compound are reacted in a hydrocarbon solvent to prepare a lithium amide compound, which is reacted with an alkyl dihalide represented by the following general formula (C), and further reacted with an organic lithium compound. is obtained by

In general formula (C), X ¹ and X ² each independently represent an I atom, a Br atom, or a Cl atom, and R ^3a is an alkylene group having 1 to 20 carbon atoms, preferably 2 to 2 carbon atoms. 16 alkylene groups, more preferably an alkylene group having 3 to 10 carbon atoms.
Examples of the compound represented by the general formula (C) include, but are not limited to, 1-bromo-3-chloropropane, 1-bromo-4-chlorobutane, 1-bromo-5-chloropentane, 1-bromo- 6-chlorohexane, 1-bromo-10-chlorodecane, 1-bromo-3-iodopropane, 1-bromo-4-iodobutane, 1-bromo-5-iodopentane, 1-bromo-6-iodohexane, 1- Bromo-10-iododecane, 1-chloro-3-iodopropane, 1-chloro-4-iodobutane, 1-chloro-5-iodopentane, 1-chloro-6-iodohexane, 1-chloro-10-iododecane be done.
From the viewpoint of reactivity and safety, the compounds represented by the general formula (C) are 1-bromo-3-chloropropane, 1-bromo-4-chlorobutane, 1-bromo-5-chloropentane, 1-bromo- 6-chlorohexane and 1-bromo-10-chlorodecane are preferred, and 1-bromo-3-chloropropane, 1-bromo-4-chlorobutane and 1-bromo-6-chlorohexane are more preferred.

<Polar compound>
A polar compound may be added to the system during the preparation of the organolithium compound described above. This tends to promote production and facilitate solubilization in hydrocarbon solvents. Examples of polar compounds include, but are not limited to, tertiary monoamines, tertiary diamines, linear or cyclic ethers.

Examples of tertiary monoamines include, but are not limited to, trimethylamine, triethylamine, methyldiethylamine, 1,1-dimethoxytrimethylamine, 1,1-diethoxytrimethylamine, 1,1-diethoxytriethylamine, N,N-dimethylformamide. diisopropyl acetal, N,N-dimethylformamide dicyclohexyl acetal.

Examples of tertiary diamines include, but are not limited to, N,N,N',N'-tetramethyldiaminomethane, N,N,N',N'-tetramethylethylenediamine, N,N,N', N'-tetramethylpropanediamine, N,N,N',N'-tetramethyldiaminobutane, N,N,N',N'-tetramethyldiaminopentane, N,N,N',N'-tetramethyl Hexanediamine, dipiperidinopentane, dipiperidinoethane.

Examples of chain ethers include, but are not limited to, dimethyl ether, diethyl ether, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, and tetraethylene dimethyl ether.

Cyclic ethers include, but are not limited to, tetrahydrofuran, bis(2-oxolanyl)ethane, 2,2-bis(2-oxolanyl)propane, 1,1-bis(2-oxolanyl)ethane, 2,2 -bis(2-oxolanyl)butane, 2,2-bis(5-methyl-2-oxolanyl)propane and 2,2-bis(3,4,5-trimethyl-2-oxolanyl)propane.

Among the polar compounds, tertiary monoamines trimethylamine, triethylamine; tertiary diamines N,N,N',N'-tetramethylethylenediamine; cyclic ethers tetrahydrofuran, 2,2-bis(2-oxolanyl)propane is preferred. A polar compound may be used individually by 1 type, and may be used in combination of 2 or more type.

When a polar compound is added when preparing the organolithium compound described above, it is preferably added in the range of 30 mass ppm or more and 50,000 mass ppm to the solvent used when preparing, and 200 mass ppm or more. It is more preferable to add within the range of 20,000 ppm by mass or less.
In order to sufficiently express the effects of accelerating the reaction and solubilizing in the solvent, it is preferable to add 30 ppm by mass or more, and to ensure the degree of freedom of microstructure adjustment in the subsequent polymerization process and to remove the solvent after polymerization. Considering the separation from the polymerization solvent in the steps of recovery and purification, it is preferably added at 50,000 ppm by mass or less.

The conjugated diene-based polymer before modification is conjugated using a polymerization initiator system containing an organolithium compound having at least one nitrogen atom in the molecule described above, or a compound having at least one nitrogen atom and an organolithium compound. It can be obtained by polymerizing using a diene compound or by copolymerizing a conjugated diene compound and an aromatic vinyl compound.

When producing a conjugated diene-based polymer containing nitrogen atoms, in the polymerization step, an organic lithium compound having at least one nitrogen atom in the molecule is prepared in advance in a predetermined reactor, and the conjugated diene compound is polymerized. Alternatively, the conjugated diene compound and the aromatic vinyl compound may be supplied to a reactor for copolymerization and the polymerization reaction may be performed, or the above-mentioned compound having at least one nitrogen atom in the molecule and the organolithium compound may be mixed statically. A mixer or an in-line mixer may be used to mix and prepare.
The polymerization initiator system may be one type or a mixture of two or more types when using the above-described organolithium compound having at least one nitrogen atom in the molecule.

The conjugated diene-based polymer before modification is polymerized using a conjugated diene compound using a polymerization initiator system containing a compound having at least one nitrogen atom in the molecule and an organic lithium compound, or a conjugated diene compound obtained by a polymerization step of copolymerizing with an aromatic vinyl compound.

In the polymerization step, the polymerization may be performed by either a batch system or a continuous system, but from the viewpoint of stably producing the polymer, the continuous system is preferable. It is more preferable to carry out the polymerization in a continuous manner in the above connected reactors.

The polymerization process of the organolithium compound may be continuous or batchwise. From the viewpoint of production efficiency, the monomer containing the conjugated diene compound and the polymerization initiator are continuously supplied to A continuous mode of polymerization is preferred. In the case of continuous polymerization, the monomers, solvent, and polymerization initiator used for polymerization may be separately fed to the polymerization vessel, or a method using a mixing vessel equipped with a stirrer, or a static mixer or line mixer in the piping. It may be a method of continuously mixing using.

The polymerization temperature is not particularly limited as long as the anionic polymerization proceeds, the chain transfer reaction is controlled, and the number of blocks in which 30 or more aromatic vinyl compound units are chained is small or absent, but from the viewpoint of productivity. Therefore, the temperature is preferably 45°C or higher, and more preferably 100°C or lower, more preferably 70°C, from the viewpoint of controlling the chain transfer reaction and ensuring a sufficient reaction amount of the modifier with respect to the active terminal after the polymerization. 95° C. or less is more preferable, and 80° C. or more and 90° C. or less is even more preferable.

In the polymerization process, from the viewpoint of controlling the chain transfer reaction described above, solid The content (also referred to as "monomer concentration") is preferably 16% by mass or less, more preferably 15% by mass or less, and even more preferably 14% by mass or less. Although the lower limit of the solid content is not particularly limited, it is preferably 12.5% by mass or more.

<Conjugated diene polymer>
The conjugated diene-based polymer before modification of the modified conjugated diene-based polymer of the present embodiment is obtained by polymerizing at least a conjugated diene compound in a hydrocarbon solvent, and copolymerizes a conjugated diene compound and an aromatic vinyl compound. you can get it.
The conjugated diene-based polymer is preferably obtained by growing an anionic polymerization reaction using a continuous polymerization method using an organic lithium compound having at least one nitrogen atom in the molecule as a polymerization initiator. In particular, the conjugated diene-based polymer is more preferably a polymer having an active terminal obtained by a growth reaction by living anionic polymerization. This makes it possible to obtain a modified conjugated diene-based polymer with a high degree of modification.

<Conjugated diene compound>
The conjugated diene compound is not limited to the following as long as it is a polymerizable monomer. Examples include 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, -methyl-1,3-pentadiene, 1,3-heptadiene, 1,3-hexadiene. Among these, 1,3-butadiene and isoprene are preferred from the viewpoint of industrial availability. These may be used alone or in combination of two or more.

<Aromatic vinyl compound>
The aromatic vinyl compound is not limited to the following as long as it is a monomer copolymerizable with the conjugated diene compound. Examples include styrene, p-methylstyrene, α-methylstyrene, vinylethylbenzene, vinylxylene, vinylnaphthalene, Diphenylethylene is mentioned. Among these, styrene is preferable from the viewpoint of industrial availability. These may be used alone or in combination of two or more.

<Solvent>
It is preferable that the polymerization step is performed in a solvent. Examples of the solvent include hydrocarbon solvents such as saturated hydrocarbons and aromatic hydrocarbons. Examples of specific hydrocarbon solvents include, but are not limited to, aliphatic hydrocarbons such as butane, pentane, hexane, and heptane; alicyclic hydrocarbons such as cyclopentane, cyclohexane, methylcyclopentane, and methylcyclohexane; Aromatic hydrocarbons such as benzene, toluene, and xylene, and hydrocarbons consisting of mixtures thereof can be mentioned.

The amount of bonded conjugated diene in the modified conjugated diene polymer of the present embodiment before modification is not particularly limited, but is preferably 50% by mass or more and 100% by mass or less, and 60% by mass or more. It is more preferably 80% by mass or less.
In addition, although the amount of bound aromatic vinyl in the conjugated diene-based polymer before modification of the modified conjugated diene-based polymer of the present embodiment is not particularly limited, it is preferably 30% by mass or more and 50% by mass or less. It is more preferable that it is not less than 40% by mass and not more than 40% by mass. When the amount of bound conjugated diene and the amount of bound aromatic vinyl are within the above ranges, it is possible to obtain a vulcanizate having a better balance between low hysteresis loss and wet skid resistance, as well as more satisfactory abrasion resistance and breaking strength. tend to be able. Here, the amount of bound aromatic vinyl can be measured by ultraviolet absorption of the phenyl group, and the amount of bound conjugated diene can also be obtained from this. Specifically, it can be measured according to the method described in the examples below.
Here, when the modified conjugated diene-based polymer is a copolymer of butadiene and styrene, the butadiene bond unit is The vinyl bond content (1,2-bond content) of can be determined. Specifically, it is measured by the method described in the examples below.

The conjugated diene-based polymer may be a random copolymer or a block copolymer. Examples of random copolymers include, but are not limited to, butadiene-isoprene random copolymers, butadiene-styrene random copolymers, isoprene-styrene random copolymers, and butadiene-isoprene-styrene random copolymers. be done. The composition distribution of each monomer in the copolymer chain is not particularly limited. A copolymer is mentioned. The bonding mode of the conjugated diene, ie, the composition of 1,4-bonds, 1,2-bonds, etc., may be uniform or may be distributed.

Examples of block copolymers include, but are not limited to, type 2 block copolymers consisting of 2 blocks, type 3 block copolymers consisting of 3 blocks, and type 4 block copolymers consisting of 4 blocks. mentioned. For example, S represents a block composed of an aromatic vinyl compound such as styrene, and B represents a block composed of a conjugated diene compound such as butadiene or isoprene and/or a block composed of a copolymer of an aromatic vinyl compound and a conjugated diene compound. When expressed, it is represented by an S-B2 type block copolymer, an S-B-S3 type block copolymer, an S-B-S-B4 type block copolymer, and the like.

In each of the above formulas, the boundaries of each block do not necessarily need to be clearly distinguished. For example, when block B is a copolymer of an aromatic vinyl compound and a conjugated diene compound, the aromatic vinyl compound in block B may be uniformly distributed or tapered. Moreover, in the block B, a plurality of portions in which the aromatic vinyl compound is uniformly distributed and/or portions in which the aromatic vinyl compound is distributed in a tapered manner may coexist. Furthermore, in block B, a plurality of segments having different aromatic vinyl compound contents may coexist. When multiple blocks S and multiple blocks B are present in the copolymer, their structures such as molecular weights and compositions may be the same or different.

In the present embodiment, the conjugated diene-based polymer obtained by the production method described above is further hydrogenated in an inert solvent to convert all or part of the double bonds into saturated hydrocarbons. can. In that case, the heat resistance and weather resistance tend to be improved, and the deterioration of the product when processed at high temperatures can be prevented. As a result, it exhibits even better performance in various applications such as automobile applications.

The degree of hydrogenation of unsaturated double bonds based on the conjugated diene compound (simply referred to as “hydrogenation rate”) can be arbitrarily selected according to the purpose and is not particularly limited. When used as a vulcanized rubber, it is preferable that the double bonds of the conjugated diene part remain partially. From this point of view, the hydrogenation rate of the conjugated diene part in the polymer is preferably 3.0% or more and 70% or less, more preferably 5.0% or more and 65% or less, and 10% or more and 60%. More preferably: Further, the hydrogenation rate of the aromatic double bond based on the aromatic vinyl compound in the copolymer of the conjugated diene compound and the aromatic vinyl compound is not particularly limited, but is preferably 50% or less. % or less, more preferably 20% or less. The hydrogenation rate can be determined by a nuclear magnetic resonance spectrometer (NMR).

The hydrogenation method is not particularly limited, and known methods can be used. A suitable hydrogenation method includes a method of hydrogenating by blowing gaseous hydrogen into a polymer solution in the presence of a catalyst. Examples of catalysts include heterogeneous catalysts such as catalysts in which noble metals are supported on porous inorganic substances; catalysts in which salts such as nickel and cobalt are solubilized and reacted with organic aluminum and the like; and metallocenes such as titanocene are used. Homogeneous catalysts such as catalysts can be mentioned. Among these, a titanocene catalyst is preferable from the viewpoint that particularly mild hydrogenation conditions can be selected. Hydrogenation of aromatic groups can also be carried out by using a noble metal-supported catalyst.

Specific examples of the hydrogenation catalyst are not limited to the following, but for example: (1) Supported heterogeneous catalysts in which metals such as Ni, Pt, Pd, and Ru are supported on carbon, silica, alumina, diatomaceous earth, etc. (2) a so-called Ziegler-type hydrogenation catalyst using an organic acid salt such as Ni, Co, Fe, Cr or a transition metal salt such as acetylacetone salt and a reducing agent such as organic aluminum; (3) Ti , Ru, Rh, Zr and other so-called organometallic complexes. Furthermore, as a hydrogenation catalyst, for example, Hydrogenation catalysts described in JP-A-2-9041 and JP-A-8-109219 are also included. Preferred hydrogenation catalysts include reaction mixtures of titanocene compounds and reducing organometallic compounds.

If allenes, acetylenes and the like are contained as impurities in the conjugated diene compound, there is a risk of inhibiting the modification reaction described below. Therefore, the total content concentration (mass) of these impurities is preferably 200 mass ppm or less, more preferably 100 mass ppm or less, and 50 mass ppm or less with respect to the total amount of the conjugated diene compound. is more preferable. Allenes include, for example, propadiene and 1,2-butadiene. Acetylenes include, for example, ethylacetylene and vinylacetylene.

Low hysteresis loss when the microstructure (the amount of each bond in the modified conjugated diene copolymer) is in the above range and the glass transition temperature of the copolymer is in the range of −45° C. or more and −15° C. or less A better vulcanizate can be obtained with a better balance of toughness and wet skid resistance.

Regarding the glass transition temperature, according to ISO22768:2006, a DSC curve is recorded while increasing the temperature in a predetermined temperature range, and the peak top (Inflection point) of the DSC differential curve is taken as the glass transition temperature. Specifically, it is measured by the method described in the examples below.

When the conjugated diene-based polymer before modification of the modified conjugated diene-based polymer of the present embodiment is a copolymer of a conjugated diene compound and an aromatic vinyl compound, a block in which 30 or more aromatic vinyl units are chained Few or none are preferred. Specifically, when the copolymer is a butadiene-styrene copolymer, the Kolthoff method (the method described in IM KOLTHOFF, et al., J. Polym. Sci. 1, 429 (1946)) In a known method of decomposing a polymer and analyzing the amount of polystyrene insoluble in methanol, the block having 30 or more aromatic vinyl units linked is preferably 5.0% by mass or less with respect to the total amount of the polymer, More preferably, it is 3.0% by mass or less.

(denaturation step)
In the modified conjugated diene-based polymerization production method of the present embodiment, a conjugated diene-based polymer is modified with a modifier having four or more alkoxy groups bonded to silyl groups in one molecule and a tertiary amino group. Includes a denaturation step.

<Modifier>
Modifiers include, but are not limited to, 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 -(5-trimethoxysilylpentyl)-1-aza-2-silacycloheptane tris(3-trimethoxysilylpropyl)amine, tris(3-methyldimethoxysilylpropyl)amine, tris(3-triethoxysilylpropyl) Amines, tris(3-methyldiethoxysilylpropyl)amine.

From the viewpoint of fuel-saving performance, the modifier preferably contains a modifier represented by any one of the following general formulas (10) to (12).

In general formula (10), 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 is an alkylene group having 1 to 10 carbon atoms. and R ⁶ represents an alkylene group having 1 to 20 carbon atoms. m represents an integer of 1 or 2; n represents an integer of 2 or 3; (m+n) is an integer of 4 or more. When a plurality of R ¹ to R ⁴ are present, they are each independent and may be the same or different.

In general formula (11), 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 each independently represent a carbon represents an alkylene group of numbers 1 to 20; m, n, and l each independently represent an integer of 1 to 3, and (m+n+l) represents an integer of 4 or more. When a plurality of R ¹ to R ⁶ are present, they are each independent and may be the same or different.

In general formula (12), 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 and R ⁶ each independently represent a carbon represents an alkylene group of numbers 1 to 20; m and n each independently represent an integer of 1 to 3, (m+n) represents an integer of 4 or more, R ⁷ is an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or represents a silyl group substituted with a hydrocarbon group. When a plurality of R ¹ to R ⁴ are present, they are each independent and may be the same or different.

Examples of modifiers represented by formula (10) include, but are not limited to, 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-sila Cyclohexane, 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-trimethoxysilyl propyl)-1-aza-2-silacyclopentane, 2-ethoxy, 2-ethyl-1-(3-triethoxysilylpropyl)-1-aza-2-silacyclopentane, 2-methoxy, 2-methyl- 1-(3-dimethoxymethylsilylpropyl)-1-aza-2-silacyclopentane, 2-ethoxy,2-ethyl-1-(3-diethoxyethylsilylpropyl)-1-aza-2-silacyclopentane is mentioned.

Among these, those in which m is 2 and n is 3 are preferable from the viewpoint of reactivity and interaction between the functional group of the modifier and the inorganic filler such as silica, and from the viewpoint of workability. Specifically, 2,2-dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza-2-silacyclopentane, 2,2-diethoxy-1-(3-triethoxysilylpropyl)-1 -aza-2-silacyclopentane is preferred.

There are no particular restrictions on the reaction temperature, reaction time, etc. when the modifying agent of general formula (10) is reacted with the polymerization active terminal, but the reaction is preferably carried out at 0° C. or higher and 120° C. or lower for 30 seconds or longer.
The total number of moles of the alkoxy groups bonded to the silyl groups in the modifier compound represented by the general formula (10) is 0.0. It is preferably in the range of 6 to 3.0 times, more preferably in the range of 0.8 to 2.5 times, and in the range of 0.8 to 2.0 times It is even more preferable to have From the viewpoint of obtaining a sufficient modification rate, molecular weight and branched structure of the resulting modified conjugated diene-based polymer, it is preferably 0.6 times or more. In addition to the fact that it is preferable to obtain the polymer component, it is preferable to set the ratio to 3.0 times or less from the viewpoint of the cost of the modifier.

Modifiers represented by general formula (11) include, but are not limited to, tris(3-trimethoxysilylpropyl)amine, tris(3-methyldimethoxysilylpropyl)amine, tris(3-triethoxy silylpropyl)amine, tris(3-methyldiethoxysilylpropyl)amine, tris(trimethoxysilylmethyl)amine, tris(2-trimethoxysilylethyl)amine, tris(4-trimethoxysilylbutyl)amine. .
Among these, it is preferable that n, m, and l all represent 3 from the viewpoint of reactivity and interaction between the functional group of the modifier and the inorganic filler such as silica, and from the viewpoint of workability. . Preferred specific examples include tris(3-trimethoxysilylpropyl)amine and tris(3-triethoxysilylpropyl)amine.

There are no particular restrictions on the reaction temperature, reaction time, etc. when the modifying agent represented by the general formula (11) is reacted with the polymerization active terminal, but the reaction should be carried out at 0° C. or higher and 120° C. or lower for 30 seconds or longer. is preferred.
The total number of moles of alkoxy groups bonded to silyl groups in the modifier compound represented by the general formula (11) is 0.6 times or more the number of moles of lithium constituting the polymerization initiator system described above, and 3.0. It is preferably in the range of 0.8 times or more and 2.5 times or less, more preferably in the range of 0.8 times or more and 2.0 times or less. . From the viewpoint of obtaining a sufficient modification rate, molecular weight, and branched structure in the modified conjugated diene-based polymer, it is preferably 0.6 times or more. In addition to the fact that it is preferable to obtain the component, from the viewpoint of modifier cost, it is preferable to make it 3.0 times or less.

Modifiers represented by general formula (12) include, but are not limited to, bis(3-(methylamino)propyl)trimethoxysilane, bis(3-(ethylamino)propyl)trimethoxysilane, bis(3-(propylamino)propyl)trimethoxysilane and bis(3-(butylamino)propyl)trimethoxysilane. Among these, n, m, and l are all preferably 3 from the viewpoint of reactivity and interaction between the functional group of the modifier and the inorganic filler such as silica, and from the viewpoint of workability. Preferred specific examples include su(3-(methylamino)propyl)trimethoxysilane and bis(3-(ethylamino)propyl)trimethoxysilane.

There are no particular restrictions on the reaction temperature, reaction time, etc. when the modifying agent represented by the general formula (12) is reacted with the polymerization active terminal, but the reaction should be carried out at 0° C. or higher and 120° C. or lower for 30 seconds or longer. is preferred.

The modifier includes a modifier represented by the general formula (10) from the viewpoint of obtaining a modified conjugated diene-based polymer having an excellent balance between fuel economy performance and wet grip performance when vulcanized, and m is 2 and n is 3 in general formula (10), or a modifier represented by general formula (11) is included, and m, n, and l in general formula (11) are all Modifiers that are 3 are preferred.

The total number of moles of the alkoxy groups bonded to the silyl groups in the modifier compound represented by the general formula (12) is 0.0 to the number of added moles of the alkali metal compound and/or alkaline earth metal compound of the polymerization initiator. It is preferably in the range of 6 times or more and 4.0 times or less, more preferably in the range of 0.8 times or more and 3.5 times or less, and in the range of 0.8 times or more and 3.0 times or less. is more preferable.
From the viewpoint of sufficiently increasing the modification rate of the resulting modified conjugated diene polymer and improving the low hysteresis property of the polymer, it is preferably 0.6 times or more. is preferably coupled to obtain a branched polymer component, and from the viewpoint of modifier cost, it is preferably 4.0 times or less.

In the method for producing a modified conjugated diene-based polymer of the present embodiment, after the modification reaction, a deactivator, a neutralizer, or the like may be added to the copolymer solution, if necessary. Examples of quenching agents include, but are not limited to, water; alcohols such as methanol, ethanol, and isopropanol. Examples of neutralizing agents include, but are not limited to, carboxylic acids such as stearic acid, oleic acid and versatic acid; aqueous solutions of inorganic acids; and carbon dioxide gas.

A rubber stabilizer is preferably added to the modified conjugated diene-based polymer of the present embodiment from the viewpoint of preventing gel formation after polymerization and improving the stability during processing. The rubber stabilizer is not limited to the following ones, and known ones can be used. Antioxidants such as -(4'-hydroxy-3',5'-di-tert-butylphenol) propinate and 2-methyl-4,6-bis[(octylthio)methyl]phenol are preferred.

In order to improve the processability of the modified conjugated diene-based polymer of the present embodiment, extender oil can be added to the modified conjugated diene-based copolymer, if necessary. The method of adding the extender oil to the modified conjugated diene-based polymer is not limited to the following, but the extender oil is added to the polymer solution and mixed to form an oil-extended copolymer solution, which is desolvated. A method is preferred. Extender oils include, for example, aromatic oils, naphthenic oils, and paraffin oils. Among these, from the viewpoints of environmental safety, prevention of oil bleed and wet grip properties, aromatic alternative oils containing 3% by mass or less of polycyclic aromatic (PCA) components according to the IP346 method are preferred. Examples of aromatic alternative oils include TDAE (Treated Distillate Aromatic Extracts) and MES (Mild Extraction Solvate) shown in Kautschuk Gummi Kunststoffe 52 (12) 799 (1999), as well as RAE (Residual Aromatic Extracts). The amount of the extender oil added is not particularly limited, but is preferably 10 parts by mass or more and 60 parts by mass or less, more preferably 15 parts by mass or more and 40 parts by mass or less, relative to 100 parts by mass of the modified conjugated diene polymer.

(Desolvation step)
A known method can be used as a method for obtaining the modified conjugated diene-based polymer of the present embodiment from a polymer solution. For example, after separating the solvent by steam stripping or the like, the polymer is separated by filtration, dehydrated and dried to obtain the polymer, concentrated in a flushing tank, and further vented extruder. and a method of directly devolatilizing with a drum dryer or the like.

[Modified conjugated diene polymer composition]
The modified conjugated diene-based polymer of this embodiment is suitably used as a vulcanizate.
The vulcanizate is, for example, the modified conjugated diene-based polymer of the present embodiment, and optionally inorganic fillers such as silica-based inorganic fillers and carbon black, and modified conjugated diene-based polymers other than the modified conjugated diene-based polymer of the present embodiment. A rubber-like polymer, a silane coupling agent, a rubber softener, wax, a vulcanizing agent, a vulcanization accelerator, a vulcanization aid, etc. are mixed to form a modified conjugated diene polymer composition, which is then heated. It can be obtained by vulcanizing with
The modified conjugated diene polymer composition of the present embodiment contains a rubber component and a filler of 5.0 parts by mass or more and 150 parts by mass or less per 100 parts by mass of the rubber component, and the rubber component is the It is preferable that the modified conjugated diene-based polymer of the present embodiment is contained in an amount of 10% by mass or more based on the total amount of the rubber component.

(rubber component)
As the rubber component used in the modified conjugated diene-based polymer composition, a rubber-like polymer other than the modified conjugated diene-based polymer of the present embodiment can be used in combination with the modified conjugated diene-based polymer of the present embodiment.
Examples of such rubber-like polymers include, but are not limited to, conjugated diene polymers or hydrogenated products thereof, random copolymers of conjugated diene compounds and vinyl aromatic compounds or hydrogenated products thereof, Examples include block copolymers of conjugated diene compounds and vinyl aromatic compounds or hydrogenated products thereof, non-diene polymers, and natural rubber.
More specific rubber-like polymers include, for example, butadiene rubber or hydrogenated products thereof, isoprene rubber or hydrogenated products thereof, styrene-butadiene rubber or hydrogenated products thereof, styrene-butadiene block copolymers or hydrogenated products thereof. styrene-based elastomers such as styrene-isoprene block copolymers or hydrogenated products thereof, acrylonitrile-butadiene rubbers or hydrogenated products thereof.

Rubber-like polymers of non-diene polymers 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. olefinic elastomer; butyl rubber, brominated butyl rubber, acrylic rubber, fluororubber, silicone rubber, chlorinated polyethylene rubber, epichlorohydrin rubber, α, β-unsaturated nitrile-acrylate-conjugated diene copolymer rubber, urethane rubber, poly Sulfurized rubber is mentioned.

The various rubber-like polymers described above may be modified rubbers to which polar functional groups such as hydroxyl groups and amino groups have been added. In addition, the weight average molecular weight is preferably 2,000 or more and 2,000,000 or less, more preferably 5,000 or more and 1,500,000 or less, from the viewpoint of the balance between performance and processing characteristics. preferable. The weight average molecular weight can be measured by a method similar to the method for measuring the modified conjugated diene polymer described in Examples. A so-called liquid rubber having a low molecular weight can also be used as the rubber-like polymer. These rubber-like polymers may be used alone or in combination of two or more.

The modified conjugated diene-based polymer composition of the present embodiment contains a rubber component and a filler of 5.0 parts by mass or more and 150 parts by mass or less per 100 parts by mass of the rubber component.
In particular, it is more preferable to contain 100 parts by mass of a rubber component containing 20% by mass or more of the above modified conjugated diene-based polymer and 0.5 parts by mass or more and 150 parts by mass or less of a silica-based inorganic filler.
By dispersing the silica-based inorganic filler in the modified conjugated diene-based polymer of the present embodiment, the vulcanized product has an excellent balance between low hysteresis loss and wet skid resistance, and is practically sufficient. It has excellent wear resistance and breaking strength, and tends to impart excellent workability when formed into a vulcanizate.

When the modified conjugated diene-based polymer composition of the present embodiment is used for vulcanized rubber applications such as automobile parts such as tires and anti-vibration rubber, and shoes and the like, it preferably contains a silica-based inorganic filler.
The silica-based inorganic filler is not particularly limited, and known ones can be used. Solid particles containing SiO ₂ or Si ₃ Al as a structural unit _are preferable _, and It is more preferable to use it as a component. Here, the main component means a component contained in the silica-based inorganic filler in an amount of 50% by mass or more, preferably 70% by mass or more, more preferably 80% by mass or more.

Examples of silica-based inorganic fillers include, but are not limited to, inorganic fibrous substances such as silica, clay, talc, mica, diatomaceous earth, wollastonite, montmorillonite, zeolite, and glass fiber. Commercially available products of silica include, for example, the trade name “Ultrasil 7000GR” manufactured by Evonik Degussa. In addition, a silica-based inorganic filler having a hydrophobized surface, and a mixture of a silica-based inorganic filler and a non-silica-based inorganic filler may also be used. Among these, from the viewpoint of strength and abrasion resistance, silica and glass fiber are preferred, and silica is more preferred. Examples of silica include dry silica, wet silica, and synthetic silicate silica. Among these, wet silica is more preferable from the viewpoint of an excellent balance between the effect of improving fracture properties and wet skid resistance. In the modified conjugated diene-based polymer composition, from the viewpoint of obtaining practically good wear resistance and fracture characteristics, the nitrogen adsorption specific surface area of the silica-based inorganic filler obtained by the BET adsorption method is 100 m ² /g or more and 300 m ² . /g or less, more preferably 170 m ² /g or more and 250 m ² /g or less. In addition, if necessary, a silica-based inorganic filler having a relatively small specific surface area (for example, a silica-based inorganic filler having a specific surface area of 200 m ² /g or less) and a silica-based inorganic filler having a specific surface area of 200 m ² /g or more can be used. system inorganic filler) and can be used in combination. This makes it possible to achieve a high balance between good wear resistance and fracture properties and low hysteresis loss.

As described above, the blending amount of the silica-based inorganic filler in the modified conjugated diene-based polymer composition is such that the inorganic filler is sufficiently dispersed and the workability and mechanical strength of the composition are practically sufficient. from the viewpoint of the rubber component containing the modified conjugated diene polymer of the present embodiment, it is preferably 0.5 parts by mass or more and 150 parts by mass or less, and 5.0 parts by mass or more and 100 parts by mass or less. is more preferable, and 20 parts by mass or more and 100 parts by mass or less is even more preferable.

The modified conjugated diene polymer composition of the present embodiment may contain carbon black. Examples of carbon black include, but are not limited to, each class of carbon black such as SRF, FEF, HAF, ISAF, and SAF. Commercially available products include, for example, Tokai Carbon Co., Ltd.'s trade name " ^SEAST KH (N339)". of carbon black is preferred.

The amount of carbon black compounded is preferably 0.5 parts by mass or more and 100 parts by mass or less, and 3.0 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 modified conjugated diene polymer of the present embodiment. is more preferable, and 5.0 parts by mass or more and 50 parts by mass or less is even more preferable. The amount of carbon black compounded is preferably 0.5 parts by mass or more from the viewpoint of expressing the performance required for tires such as dry grip performance and conductivity, and 100 parts by mass from the viewpoint of dispersibility. It is preferable to:

The modified conjugated diene polymer composition of the present embodiment may contain a metal oxide or metal hydroxide in addition to the silica-based inorganic filler or carbon black. The metal oxide refers to a solid particle having the chemical formula MxOy (M represents a metal atom, and x and y each represent an integer of 1 to 6) as a main component of a structural unit. For example, alumina , titanium oxide, magnesium oxide, and zinc oxide can be used. Mixtures of metal oxides and inorganic fillers other than metal oxides can also be used. Examples of metal hydroxides include, but are not limited to, aluminum hydroxide, magnesium hydroxide, and zirconium hydroxide.

The modified conjugated diene polymer composition of the present embodiment may contain a silane coupling agent. The silane coupling agent has the function of enhancing the interaction between the rubber component and the silica-based inorganic filler, and has groups that have affinity or bonding to the rubber component and the silica-based inorganic filler, respectively. A compound having a sulfur-bonding portion, an alkoxysilyl group, and a silanol group portion in one molecule is generally used. For example, bis-[3-(triethoxysilyl)-propyl]-tetrasulfide, bis-[3-(triethoxysilyl)-propyl]-disulfide, bis-[2-(triethoxysilyl)-ethyl]-tetra sulfides, and commercially available products include, for example, the product name "Si75" manufactured by Evonik Degussa.

The amount 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, relative to 100 parts by mass of the silica-based inorganic filler. 1.0 parts by mass or more and 15 parts by mass or less is more preferable. When the blending amount of the silane coupling agent is within the above range, there is a tendency that the above addition effect of the silane coupling agent can be made more remarkable.

The modified conjugated diene polymer composition of the present embodiment may contain a softening agent for rubber in order to improve workability. Suitable rubber softeners are mineral oils or liquid or low molecular weight synthetic softeners. Mineral oil-based rubber softeners called process oils or extender oils used for softening, increasing volume, and improving workability of rubber are mixtures of aromatic rings, naphthenic rings, and paraffin chains, A paraffinic chain having 50% or more carbon atoms in the total carbon is called a paraffinic chain, a naphthenic chain having a naphthenic ring carbon number of 30% or more and 45% or less, and an aromatic carbon number exceeding 30%. They are called aromatic systems. Commercially available products include, for example, S-RAE oil, trade name “JOMO Process NC140” manufactured by Japan Energy Co., Ltd. As the rubber softening agent to be used together with the modified conjugated diene-aromatic vinyl copolymer of the present embodiment, those having an appropriate aromatic content tend to have good compatibility with the copolymer, and are therefore preferred.

The amount of the rubber softener to be blended is preferably 0 parts by mass or more and 100 parts by mass or less, and 10 parts by mass or more and 90 parts by mass or less with respect to 100 parts by mass of the rubber component containing the modified conjugated diene polymer of the present embodiment. is more preferable, and 30 parts by mass or more and 90 parts by mass or less is even more preferable. When the amount of the rubber softener to be blended is 100 parts by mass or less with respect to 100 parts by mass of the rubber component, bleed out and stickiness of the composition surface tend to be suppressed.

About the method of mixing the modified conjugated diene-based polymer of the present embodiment with other rubber-like polymers, silica-based inorganic fillers, carbon black and other fillers, silane coupling agents, additives such as rubber softeners is not particularly limited. As a method, for example, a melt-kneading method using a general kneader such as an open roll, a Banbury mixer, a kneader, a single-screw extruder, a twin-screw extruder, a multi-screw extruder, etc., each component is dissolved and mixed After that, a method of removing the solvent by heating can be mentioned. Among these, melt-kneading methods using rolls, Banbury mixers, kneaders, and extruders are preferred from the viewpoint of productivity and good kneading properties. In addition, both a method of kneading the modified conjugated diene-based polymer and various compounding agents at once and a method of mixing the mixture in multiple batches can be applied.

The modified conjugated diene-based polymer composition may be a vulcanized composition that has been vulcanized with a vulcanizing agent. Examples of vulcanizing agents 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. Sulfur compounds include sulfur monochloride, sulfur dichloride, disulfide compounds, polymeric polysulfur compounds, and the like. The amount of the vulcanizing agent used is preferably 0.01 parts by mass or more and 20 parts by mass or less, and 0.1 parts by mass or more and 15 parts by mass with respect to 100 parts by mass of the rubber component containing the modified conjugated diene polymer of the present embodiment. Part or less is more preferable. As the vulcanization method, a conventionally known method can be applied, and the vulcanization temperature is preferably 120° C. or higher and 200° C. or lower, more preferably 140° C. or higher and 180° C. or lower.

In the vulcanization, a vulcanization accelerator and a vulcanization aid may be used as necessary. As the vulcanization accelerator, conventionally known materials can be used, for example, sulfenamide, guanidine, thiuram, aldehyde-amine, aldehyde-ammonia, thiazole, thiourea, dithiocarbamate and other vulcanization accelerators. Specific compounds include, for example, N-cyclohexyl-2-benzothiazylsulfinamide and diphenylguanidine. Examples of vulcanizing aids include, but are not limited to, zinc white and stearic acid. The amount of the vulcanization accelerator used is preferably 0.01 parts by mass or more and 20 parts by mass or less, and 0.1 parts by mass or more with respect to 100 parts by mass of the rubber component containing the modified conjugated diene polymer of the present embodiment. 15 parts by mass or less is more preferable.

The modified conjugated diene-based polymer composition of the present embodiment may contain other softening agents and fillers other than those described above, as long as the purpose of the present embodiment is not impaired, and may also contain a product name manufactured by Ouchi Shinko Chemical Co., Ltd. Various additives such as waxes such as "Sannok N", heat stabilizers, antistatic agents, weather stabilizers, anti-aging agents such as N-isopropyl-N'-phenyl-p-phenylenediamine, colorants, and lubricants are used. may As other softening agents, known softening agents can be used. Other fillers include, for example, calcium carbonate, magnesium carbonate, aluminum sulfate and barium sulfate. Known materials can be used as the heat stabilizer, antistatic agent, weather stabilizer, anti-aging agent, colorant, and lubricant.

The modified conjugated diene-based polymer composition of the present embodiment can be crosslinked by adding a vulcanizing agent, a vulcanization accelerator, various additives, etc., and used as a rubber composition for producing a desired rubber product.
The rubber composition obtained by cross-linking the modified conjugated diene-based polymer composition can be used for tires, anti-vibration rubber, and various industrial products.

Hereinafter, the present embodiment will be described in more detail with specific examples and comparative examples, but the present embodiment is not limited by the following examples and comparative examples as long as the gist thereof is not exceeded. .
Various physical properties in Examples and Comparative Examples were measured by the methods described below.

((Physical property 1) Bound styrene content)
Using a modified conjugated diene polymer as a sample, 100 mg of the sample was diluted to 100 mL with chloroform and dissolved to obtain a measurement sample.
The amount of bound styrene (% by mass) with respect to 100% by mass of the modified conjugated diene-based polymer as a sample was measured from the amount of absorption at the ultraviolet absorption wavelength (around 254 nm) by the phenyl group of styrene (trade name "UV -2450").

((Physical property 2) Microstructure of butadiene portion (1,2-vinyl bond amount))
Using a modified conjugated diene polymer as a sample, 50 mg of the sample was dissolved in 10 mL of carbon disulfide to prepare a measurement sample.
Using a solution cell, the infrared spectrum is measured in the range of 600 to 1000 cm ^-1 , and the absorbance at a given wavenumber is used to determine the microstructure of the butadiene moiety, that is, the amount of 1,2-vinyl bonds ( mol %) was determined (trade name “FT-IR230” manufactured by JASCO Corporation).

((Physical property 3) Mooney viscosity of the polymer)
Using a conjugated diene polymer before addition of a modifier or a modified conjugated diene polymer as a sample, using a Mooney viscometer (manufactured by Ueshima Seisakusho Co., Ltd., trade name "VR1132"), JIS K6300 (ISO289-1) and ISO289- 4, the Mooney viscosity was measured.
The measurement temperature was 110°C.
First, after preheating the sample for 1 minute, the rotor was rotated at 2 rpm, and the torque after 4 minutes was measured as the Mooney viscosity (ML ₍₁₊₄₎ ).

((Physical property 4) Modification rate)
Using a modified conjugated diene-based polymer as a sample, it was measured by applying the characteristics of adsorption of modified components to a GPC column with a silica-based gel as a packing material.
A sample solution containing a sample and a low-molecular-weight internal standard polystyrene was measured with a polystyrene gel column, and the difference between the chromatogram measured with a silica column was used to measure the amount of adsorption to the silica column, and the modification rate was obtained. .
Specifically, it is as shown below.
Sample preparation: 10 mg of sample and 5 mg of standard polystyrene were dissolved in 20 mL of tetrahydrofuran (THF).
Polystyrene column GPC measurement conditions: THF was used as an eluent, and 200 μL of sample was injected into the apparatus for measurement.
As columns, a guard column (trade name: "TSKguardcolumn HHR-H" manufactured by Tosoh Corporation) and three columns (trade name: "TSKgel Super Multipore HZ-H" manufactured by Tosoh Corporation) were connected and used.
Column oven temperature: 40° C., THF in TEA solution flow rate: 1.0 mL/min, measurement was performed using an RI detector (trade name “HLC8020” manufactured by Tosoh Corporation) to obtain a chromatogram.
Silica-based column GPC measurement conditions: THF was used as an eluent, and 200 μL of sample was injected into the apparatus for measurement.
The column used was a trade name “Zorbax” manufactured by DuPont. A chromatogram was obtained by measurement using an RI detector (trade name “HLC8020” manufactured by Tosoh Corporation) under conditions of a column oven temperature of 40° C. and a THF flow rate of 0.5 mL/min.
Modification rate calculation method: The total peak area of the chromatogram using a polystyrene column is set to 100, the peak area of the sample is P1, the peak area of standard polystyrene is P2, and the peak area of the chromatogram using a silica column is Assuming that the total is 100, the area of the sample is P3, and the peak area of the standard polystyrene is P4, the modification rate (% by mass) was obtained from the following formula.
Modification rate (mass%) = [1-(P2 × P3) / (P1 × P4)] × 100
(However, P1+P2=P3+P4=100)

((Physical property 5) weight average molecular weight, number average molecular weight)
Using a modified conjugated diene-based polymer or a conjugated diene-based polymer before the addition of a modifier as a sample, using a GPC measurement device in which three columns filled with polystyrene gel are connected, a chromatogram is measured, Weight average molecular weight (Mw) and number average molecular weight (Mn) were determined based on a calibration curve obtained using standard polystyrene.
Tetrahydrofuran (THF) was used as the eluent.
The column was used by connecting three guard columns: trade name "TSKguardcolumn HHR-H" manufactured by Tosoh Corporation, and columns: trade name "TSKgel SuperMultipore HZ-H" manufactured by Tosoh Corporation. An RI detector (trade name “HLC8020” manufactured by Tosoh Corporation) was used under conditions of an oven temperature of 40° C. and a THF in TEA flow rate of 1.0 mL/min. 10 mg of a sample for measurement was dissolved in 20 mL of THF to prepare a measurement solution, and 200 μL of the measurement solution was injected into a GPC measurement device for measurement.

(Ratio of modified components at both ends)
The ratio of modified components at both ends indicates the ratio of the components modified at both ends to the total amount of the conjugated diene polymer.
The ratio of modified components at both ends is calculated from the following formula, where A is the molar ratio of the amine compound to the alkyl lithium when preparing the polymerization initiator x 100 ((NH/Li) x 100), and R is the modification rate. can be done.
Modified components at both ends (%) = A × (100-(RA)) / (100-(RA) + 100-R)

[Example 1] Modified conjugated diene polymer (Sample 1)
The internal volume is 10 L, the ratio (L/D) of the internal height (L) to the diameter (D) is 4.0, the inlet is at the bottom, the outlet is at the top, and a stirrer and Two autoclaves having jackets for temperature control were connected.
Furthermore, 29.0 g/min of 1,3-butadiene, 18.9 g/min of styrene, and 18.9 g/min of styrene, n-hexane from which impurities such as moisture were removed in advance, were connected to one static mixer downstream of the outlet of the second reactor. were mixed at 180.2 g/min to obtain a mixed solution.
Immediately before this mixed solution enters the first reactor, n-butyllithium for impurity deactivation treatment is supplied at 0.087 mmol / min and mixed with a static mixer, and then the bottom of the first reactor was continuously supplied to
Further, 2,2-bis(2-oxolanyl)propane was added as a polar substance at a rate of 0.018 g/min, and as a polymerization initiator, piperidinolithium (also referred to as “1-lithiopiperidine”) was used as a lithium amide prepared in advance. ) and n-butyllithium (the molar ratio of piperidinolithium and n-butyllithium was piperidinolithium:n-butyllithium=0.75:0.25) was added to 0.180 mmol. /min to the bottom of the first reactor, and the internal temperature of the reactor was kept at 70°C.
The polymer solution was continuously withdrawn from the top of the first reactor, continuously supplied to the bottom of the second reactor, the reaction was continued at 80°C, and further supplied to the static mixer from the top of the second reactor. From the outlet of the second reactor, a small amount of the copolymer solution before the addition of the modifier was extracted, an antioxidant (BHT) was added to 0.2 g per 100 g of the polymer, the solvent was removed, and the temperature was increased to 110 ° C. The measured Mooney viscosity was 51.3.
Next, 0.038 mmol of 2,2-dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza-2-silacyclopentane as a modifier was added to the copolymer solution continuously flowing in the static mixer. /min to carry out the denaturation reaction.
An antioxidant (BHT) was continuously added to the polymer solution flowing out from the static mixer so as to be 0.2 g per 100 g of the polymer to complete the modification reaction. A coalescence (Sample 1) was obtained.
As a result of analysis of sample 1, the Mooney viscosity at 110° C. was 118, the amount of bound styrene was 37% by mass, the amount of vinyl bonds (1,2-bonds) in the butadiene unit was 39.0 mol%, and the modification rate was 83. %Met. Other physical properties of Sample 1 are also shown in Table 1.

[Example 2] Modified conjugated diene polymer (Sample 2)
A modified conjugated diene polymer (Sample 2) was obtained in the same manner as in Example 1, except that the molar ratio of lithium amide and n-butyllithium was changed to 0.55:0.45.

[Example 3] Modified conjugated diene polymer (Sample 3)
A modified conjugated diene polymer (Sample 3 ).

[ Reference Example 4] Modified conjugated diene polymer (Sample 4)
The supply of the mixed solution of lithium amide and n-butyllithium was changed to a rate of 0.36 mmol/min, the addition of the polar substance 2,2-bis(2-oxolanyl)propane was changed to a rate of 0.036 g/min, and the modification agent 2,2-dimethoxy-1-(3-trimethoxysilylpropyl)-
A modified conjugated diene polymer (Sample 4) was obtained in the same manner as in Example 1, except that the addition rate of 1-aza-2-silacyclopentane was changed to 0.14 mmol/min.

[Example 5] Modified conjugated diene polymer (Sample 5)
The supply of the mixed solution of lithium amide and n-butyllithium was changed to a rate of 0.108 mmol/min, the addition of the polar substance 2,2-bis(2-oxolanyl)propane was changed to a rate of 0.0108 g/min, and the modification In the same manner as in Example 1, except that the addition of the agent 2,2-dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza-2-silacyclopentane was changed to a rate of 0.023 mmol/min. , to obtain a modified conjugated diene polymer (Sample 5).

[Example 6] Modified conjugated diene polymer (Sample 6)
A modified conjugated diene polymer (Sample 6) was obtained in the same manner as in Example 1, except that the molar ratio of lithium amide and n-butyllithium was changed to 0.09:0.91.

[Example 7] Modified conjugated diene polymer (Sample 7)
A modified conjugated diene polymer was prepared in the same manner as in Example 1, except that the temperature of the second reactor was changed to 87° C. and the molar ratio of lithium amide and n-butyllithium was changed to 0.09:0.91. A coalescence (Sample 7) was obtained.

[Example 8] Modified conjugated diene polymer (Sample 8)
A modified conjugated diene polymer (Sample 8) was obtained in the same manner as in Example 1, except that the molar ratio of lithium amide and n-butyllithium was changed to 0.05:0.95.

[Example 9] Modified conjugated diene polymer (Sample 9)
Same as Example 1, except that 2,2-dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza-2-silacyclopentane was changed to 1,2-bis(3-triethoxysilyl)ethane. Sample 9 was obtained in the same manner.

[Example 10] Modified conjugated diene polymer (Sample 10)
Same as Example 1, except that 2,2-dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza-2-silacyclopentane was changed to bis(3-(methylamino)propyl)trimethoxysilane. Sample 10 was obtained in the same manner.

[Example 11] Modified conjugated diene polymer (Sample 11)
A modified conjugated diene polymer was prepared in the same manner as in Example 1, except that the temperature of the second reactor was changed to 90° C. and the molar ratio of lithium amide and n-butyllithium was changed to 0.28:0.73. A coalescence (Sample 11) was obtained.

[Example 12] Modified conjugated diene polymer (Sample 12)
The polymerization solution obtained in Example 1 and the polymerization solution obtained in Comparative Example 5 described later were blended so that the mass ratio was Example 1: Comparative Example 5 = 3: 1, and then the solvent was added. It was removed to obtain a modified conjugated diene polymer (Sample 12).

[Example 13] Modified conjugated diene polymer (Sample 13)
The polymerization solution obtained in Example 1 and the polymerization solution obtained in Comparative Example 5 described later were blended so that the mass ratio was Example 1: Comparative Example 5 = 9: 1, and then the solvent was added. It was removed to obtain a modified conjugated diene polymer (Sample 13).

[Comparative Example 1] Modified conjugated diene polymer (Sample 14)
A sample 14 was obtained in the same manner as in Example 1, except that the temperature of the second reactor was changed to 70°C.

[Comparative Example 2] Modified conjugated diene polymer (Sample 15)
The supply of the mixed solution of lithium amide and n-butyllithium was changed to a rate of 0.4 mmol/min, the addition of the polar substance 2,2-bis(2-oxolanyl)propane was changed to a rate of 0.04 g/min, and the modification In the same manner as in Example 1, except that the addition of the agent 2,2-dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza-2-silacyclopentane was changed to a rate of 0.084 mmol/min. , to obtain a modified conjugated diene polymer (Sample 15).

[Comparative Example 3] Modified conjugated diene polymer (Sample 16)
The supply of the mixed solution of lithium amide and n-butyllithium was changed to a rate of 0.04 mmol/min, the addition of the polar substance 2,2-bis(2-oxolanyl)propane was changed to a rate of 0.0018 g/min, and the modification In the same manner as in Example 1, except that the rate of addition of the agent 2,2-dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza-2-silacyclopentane was changed to 0.0038 mmol/min. , to obtain a modified conjugated diene polymer (Sample 16).

[Comparative Example 4] Modified conjugated diene polymer (Sample 17)
A modified conjugated diene polymer (Sample 17) was obtained in the same manner as in Example 1, except that the molar ratio of lithium amide and n-butyllithium was changed to 0.89:0.11.

[Comparative Example 5] Modified conjugated diene polymer (Sample 18)
A modified conjugated diene polymer (Sample 18) was obtained in the same manner as in Example 1, except that the molar ratio of piperidinolithium and n-butyllithium was changed to 0:1.

[Comparative Example 6] Modified conjugated diene polymer (Sample 19)
An autoclave with a stirring device and a jacket having an internal volume of 10 L was washed and dried, and after purging with nitrogen, 592 g of 1,3-butadiene, 208 g of styrene, and 5 kg of cyclohexane from which impurities such as moisture had been removed in advance were added. -Add 1.47 g of bis(2-oxolanyl)propane, and prepare a mixed solution of piperidinolithium and n-butyllithium as lithium amide prepared in advance (the molar ratio of piperidinolithium and n-butyllithium is 2.5 mmol of pipenodinolithium:n-butyllithium=0.75:0.25) was added to initiate polymerization at 52°C. The polymerization was carried out in an adiabatic manner and reached a maximum temperature of 70°C. After the polymerization was continued for 5 minutes after reaching the maximum temperature, the obtained reaction solution, that is, the polymer solution containing the conjugated diene-based polymer composed of the conjugated diene compound and the aromatic vinyl compound was sampled, and the solvent was removed. analysis was performed.
Then, a cyclohexane solution containing 1.3 mmol of 2-dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza-2-silacyclopentane was added to the polymerized solution after sampling and allowed to react for 15 minutes. After that, 2 g of an antioxidant (BHT) was added to the obtained polymer solution, and then the solvent was removed to obtain a modified conjugated diene polymer (Sample 19).

[Examples 14 to 16, Reference Example 17, Examples 18 to 26, Comparative Examples 7 to 12] Rubber Compositions The samples shown in Tables 1 and 2 (Samples 1 to 19) were used as starting rubbers, and the formulations shown below were used. ,
A rubber composition containing each raw rubber was obtained.
Raw material rubber (modified conjugated diene-based polymer (samples 1 to 19)): 100.0 parts by mass Filler 1 (silica (manufactured by Evonik Degussa under the trade name "Ultrasil 7000G
r")): 75.0 parts by mass Filler 2 (carbon black (trade name "Seist KH (N339) manufactured by Tokai Carbon Co., Ltd.
)): 5.0 parts by mass Silane coupling agent ((trade name “Si75” manufactured by Evonik Degussa): 6.0 parts by mass Process oil (S-RAE oil (trade name “JOMO process” manufactured by Japan Energy Co., Ltd.): 6.0 parts by mass NC140")): 30.0 parts by mass Wax (trade name "Sannok N" manufactured by Ouchi Shinko Kagaku Co., Ltd.): 1.5 parts by mass Zinc white: 2.5 parts by mass Stearic acid: 2.0 parts by mass Antiaging Agent (N-isopropyl-N'-phenyl-p-phenylenediamine): 2.0
Parts by mass Sulfur: 1.8 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: 229.5 parts by mass

The above materials were kneaded by the following method to obtain a rubber composition.
Raw material rubber (Samples 1 to 19) was kneaded in a closed kneader (contents 0.3 L) equipped with a temperature control device under conditions of a filling rate of 65% and a rotor speed of 50/57 rpm as the first kneading. , fillers 1 and 2 (silica, carbon black), silane coupling agent, process oil, wax, zinc oxide, and stearic acid were kneaded. At this time, the temperature of the closed mixer was controlled, and each rubber composition was obtained at a discharge temperature (compound) of 155 to 160°C.
Next, as the second step of kneading, after cooling the mixture obtained above to room temperature, an anti-aging agent was added, and kneading was performed again in order to improve dispersion of silica. In this case as well, the discharge temperature (formulation) was adjusted to 155-160° C. by controlling the temperature of the mixer.
After cooling, sulfur and vulcanization accelerators 1 and 2 were added and kneaded with an open roll set at 70° C. as the third stage of kneading.
After that, it was molded and vulcanized with a vulcanizing press at 160° C. for 20 minutes.
A rubber composition before vulcanization and a rubber composition after vulcanization were evaluated.
Specifically, it was evaluated by the following method. The results are shown in Tables 3 and 4.

((Evaluation 1) formulation Mooney viscosity)
After the second stage kneading and before the third stage kneading, the mixture obtained above is used as a sample and preheated at 130° C. for 1 minute according to JIS K6300-1 using a Mooney viscometer. After that, the viscosity was measured after rotating the rotor at 2 revolutions per minute for 4 minutes.
In Tables 3 and 4, evaluation was made with an index based on Comparative Example 11 being 100.
The smaller the value, the lower the viscosity of the compound and the better the extrusion processability.

((Evaluation 2) viscoelasticity parameter)
A viscoelasticity tester "ARES" manufactured by TA Instruments Japan was used to measure viscoelasticity parameters in a torsion mode.
In Tables 3 and 4, each measured value was evaluated by an index with Comparative Example 11 being 100.
Tan δ measured at 0° C. with a frequency of 10 Hz and a strain of 1% was used as an index of wet grip properties. A larger index indicates better wet grip.
Also, tan δ measured at 50° C. with a frequency of 10 Hz and a strain of 3% was used as an index of low hysteresis loss. A smaller index indicates better low hysteresis loss.

((Evaluation 3) breaking strength, tensile elongation)
According to JIS K 6251 "Vulcanized rubber and thermoplastic rubber-Determination of tensile properties", using a No. 3 dumbbell-shaped test piece made of a rubber composition sheet, breaking strength and tensile elongation were measured. Both were indexed with the result of Comparative Example 11 as 100. A larger value indicates better fracture resistance.

((Evaluation 4) wear resistance)
Using an Akron abrasion tester (manufactured by Yasuda Seiki Seisakusho), the amount of abrasion at a load of 44.4 N and 1000 rotations was measured in accordance with JIS K6264-2. Evaluated with an index. A larger index indicates better wear resistance.

((Evaluation 5) State of kneaded dough)
Five panelists visually observed the rubber skin (surface shape) after passing through the rolls of the unvulcanized rubber composition produced by the methods shown in the above-described Examples and Comparative Examples. Evaluated on a perfect score.
A higher score indicates a better state of the kneaded dough.

((Evaluation 6) constant strain fatigue test)
Samples for fatigue tests were prepared from the vulcanized rubber produced by the methods shown in the above-described Examples and Comparative Examples using a No. 3 dumbbell specified in JIS K6251.
A repeated elongation strain of 40% was applied to this dumbbell-shaped sample at room temperature at a rate of 400 times per minute, and the number of times until the sample broke was measured.
The results were indexed with the value of Comparative Example 11 as 100. A larger value indicates better constant strain fatigue resistance.

The modified conjugated diene-based polymer according to the present invention has industrial applicability in fields such as tire treads, automobile interior and exterior parts, anti-vibration rubber, belts, footwear, foams, and various industrial products.

Claims (11)

A modification rate of 84% by mass or less, a weight average molecular weight (Mw) of 200,000 or more and 3,000,000 or less, and a molecular weight distribution (Mw/Mn) represented by the ratio of Mw to the number average molecular weight (Mn) of 1.0. 5 or more and 3.5 or less, Mooney viscosity at 110 ° C. is 105 or more,
Having a functional group represented by the following general formula (1) at the terminal, and containing an alkoxysilyl group and an amino group in a portion different from the terminal having the functional group represented by the following general formula (1) A modified conjugated diene-based polymer having a modifying group.

(In Formula (1), R ₁ and R ₂ are each independently a group consisting of an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, and an aralkyl group having 6 to 20 carbon atoms. represents at least one selected from the group consisting of a part of which may have an unsaturated bond or a branched structure, and R ₁ and R ₂ may combine to form a ring structure together with the adjacent nitrogen atoms. , R ₁ and R ₂ in that case represent an alkyl group having 5 to 12 carbon atoms.) 2. The modified conjugated diene polymer according to claim 1, represented by the following general formula (A) or (B).

(In formula (A), R ²¹ to R ²⁴ each independently represent an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and R ²⁵ and R ²⁶ each independently , represents an alkylene group having 1 to 20 carbon atoms, and R ²⁷ represents a hydrogen atom, a silyl group substituted with a hydrocarbon, an alkyl group having 1 to 20 carbon atoms, or an aryl group having 6 to 20 carbon atoms. , b, c and d are each independently integers of 1 or 2 and b and d are integers of 0 or 1, as long as (a + b) and (c + d) are each independently integers of 2 or less (Polym) represents a conjugated diene polymer, at least one end of which has a functional group represented by the general formula (1), and the functional group at the end has the following general formula (2) A functional group represented by any one of (5), wherein R ²¹ and R ²³ when there are more than one and (Polym) when there are more than one are each independent.)

(In formula (B), R ²⁸ to R ³³ each independently represent an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and R ³⁴ to R ³⁶ each independently , represents an alkylene group having 1 to 20 carbon atoms, and a, b, c, d, e, and f are (a+b), (c+d), and (e+f) each independently representing an integer of 2 or less, a, c and e each independently represent an integer of 1 or 2, b, d and f each independently represent an integer of 0 or 1. (Polym) represents a conjugated diene-based polymer, at least one terminal thereof and the terminal functional group having the functional group represented by the general formula (1) is a functional group represented by any one of the following general formulas (2) to (5). of R ²⁸ , R ³⁰ and R ³² , and plural (Polym) are each independent.)

(In formula (2), R ¹⁰ and R ¹¹ are each independently a group consisting of an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, and an aralkyl group having 6 to 20 carbon atoms. may have an unsaturated bond or a branched structure in part thereof, and R ¹⁰ and R ¹¹ may combine to form a ring structure together with the adjacent nitrogen atom. , R ¹⁰ and R ¹¹ in that case represent an alkyl group having 5 to 12 carbon atoms. )

(In formula (3), R ¹² and R ¹³ are each independently a group consisting of an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, and an aralkyl group having 6 to 20 carbon atoms. may have an unsaturated bond or a branched structure in part thereof, and R ¹² and R ¹³ may combine to form a cyclic structure together with the adjacent nitrogen atom. , R ¹² and R ¹³ in that case represent an alkyl group having 5 to 12 carbon atoms, R ¹⁴ is an alkylene group having 1 to 30 carbon atoms which may have an aliphatic or aromatic substituent, or Indicates a conjugated diene polymer having 1 to 20 carbon atoms.)

(In formula (4), R ¹⁵ and R ¹⁶ each independently consist of an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, and an aryl group having 6 to 20 carbon atoms. represents at least one selected from the group, and may partially have an unsaturated bond or a branched structure, and R ¹⁵ and R ¹⁶ may combine to form a ring structure together with the adjacent nitrogen atoms. Well, R ¹⁵ and R ¹⁶ in that case represent an alkyl group having 5 to 12 carbon atoms. )

(In formula (5), R ¹⁷ represents a hydrocarbon group having 2 to 10 carbon atoms, and may partially have an unsaturated bond or branched structure. R ¹⁸ represents a hydrocarbon group having 1 to 12 carbon atoms. and may have a branched structure in part thereof . ) 3. The modified conjugated diene polymer according to claim 1 or 2, which contains both terminal modifying components in a range of 5% or more and 100% or less based on the total amount of said conjugated diene polymer. 4. The modified conjugated diene-based polymer according to any one of claims 1 to 3, comprising both terminal-modified components in a range of 5% or more and 50% or less based on the total amount of said conjugated diene-based polymer. A method for producing the modified conjugated diene-based polymer according to any one of claims 1 to 4,
a polymerization step of obtaining a conjugated diene-based polymer by polymerizing a conjugated diene compound and an aromatic vinyl compound using an organic lithium compound having at least one nitrogen atom in the molecule as an anionic polymerization initiator;
a modifying step of modifying the conjugated diene-based polymer with a modifying agent having four or more alkoxy groups bonded to silyl groups and a tertiary amino group in one molecule;
A method for producing a modified conjugated diene polymer. In the polymerization step, an amine compound and an alkyllithium are mixed with an NH/Li molar ratio of 0.1 to 0.75 using an organolithium compound prepared as an anionic polymerization initiator to form a conjugated diene compound and an aromatic vinyl. polymerize the compound with
The method for producing the modified conjugated diene-based polymer according to claim 5. The organolithium compound is
Including an organolithium compound represented by any one of the following general formulas (6) to (9),
A method for producing the modified conjugated diene-based polymer according to claim 5 or 6.

(In formula (6), R ₁₀ and R ₁₁ are each independently a group consisting of an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, and an aralkyl group having 6 to 20 carbon atoms. It represents at least one selected from the above, and may have an unsaturated bond or branched structure in its part.
R ₁₀ and R ₁₁ may combine to form a ring structure together with the adjacent nitrogen atoms, in which case R ₁₀ and R ₁₁ represent an alkyl group having 5 to 12 carbon atoms. )

(In formula (7), R ₁₂ and R ₁₃ are each independently a group consisting of an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, and an aralkyl group having 6 to 20 carbon atoms. It represents at least one selected from the above, and may have an unsaturated bond or branched structure in its part.
R ₁₂ and R ₁₃ may combine to form a ring structure together with the adjacent nitrogen atoms, in which case R ₁₂ and R ₁₃ represent an alkyl group having 5 to 12 carbon atoms. R ₁₄ represents an alkylene group having 1 to 20 carbon atoms or a conjugated diene polymer having 1 to 20 carbon atoms. )

(In formula (8), R ₁₅ and R ₁₆ are each independently a group consisting of an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, and an aryl group having 6 to 20 carbon atoms. It represents at least one selected from the above, and may have an unsaturated bond or branched structure in its part.
R ₁₅ and R ₁₆ may combine to form a ring structure together with the adjacent nitrogen atoms, in which case R ₁₅ and R ₁₆ represent an alkyl group having 5 to 12 carbon atoms. )

(In formula (9), R ₁₇ represents a hydrocarbon group having 2 to 10 carbon atoms, and may partially have an unsaturated bond or a branched structure. R ₁₈ represents a hydrocarbon group having 1 to 12 carbon atoms. represents an alkyl group, and may have a branched structure in its part.) The method for producing a modified conjugated diene-based polymer according to any one of claims 5 to 7, wherein in the polymerization step, the polymerization system is a continuous system and the polymerization temperature is 80°C or higher. The conjugated diene-based polymer according to any one of claims 5 to 8, wherein in the modifying step, the conjugated diene-based polymer is modified with a modifying agent represented by any one of the following general formulas (10) to (12). A method for producing a modified conjugated diene polymer.

(In formula (10), 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 is an alkylene group having 1 to 10 carbon atoms. R ⁶ represents an alkylene group having 1 to 20 carbon atoms, m represents an integer of 1 or 2, n represents an integer of 2 or 3, and (m+n) represents an integer of 4 or more. Each of R ¹ to R ⁴ is independent when a plurality of R 1 to R 4 are present.)

(In formula (11), 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 each independently , represents an alkylene group having 1 to 20 carbon atoms, m, n, and l each independently represents an integer of 1 to 3, and (m + n + l) represents an integer of 4 or more. R ¹ to R ⁶ are each independent.)

(In formula (12), 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 and R ⁶ each independently represents an alkylene group having 1 to 20 carbon atoms, each of m and n independently represents an integer of 1 to 3, and (m+n) represents an integer of 4 or more.
R ⁷ represents an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or a silyl group substituted with a hydrocarbon group. When a plurality of R ¹ to R ⁴ are present, they are each independent. ) 100 parts by mass of a rubber component;
5.0 parts by mass or more and 150 parts by mass or less of filler;
including
The rubber component contains 10% by mass or more of the modified conjugated diene-based polymer according to any one of claims 1 to 4 with respect to the total amount of the rubber component.
A modified conjugated diene polymer composition. A tire comprising the modified conjugated diene polymer composition according to claim 10 .