JP6777454B2 - Modified conjugated diene polymer composition, rubber composition for tread, and tire - Google Patents

Description

The present invention relates to a modified conjugated diene polymer composition, a rubber composition for tread, and a tire.

In recent years, consideration for the environment, such as reduction of carbon dioxide emissions, has become a social demand, and there is an increasing demand for fuel efficiency of automobiles. Since the hysteresis loss of the tread portion where the tire is in contact with the ground accounts for 50 to 60% of the rolling resistance of the entire tire, a rubber material capable of reducing the hysteresis loss of the tread portion has been conventionally developed. There is.
Rubber-like polymers, carbon black, silica, etc. used for such rubber materials have been developed, and the hysteresis loss of the tread portion has been greatly reduced due to improvements in compounding technology including these, and tires. Rolling resistance is also being greatly reduced.

However, in order to further reduce the rolling resistance of the tire, when trying to reduce the hysteresis loss in the tread part, we are looking for a method to reduce other performance such as wear resistance and grip performance on wet road surface. .. Therefore, it has also been proposed to reduce the hysteresis loss of the tread portion to reduce the rolling resistance of the tire.
As a technique for reducing rolling resistance in a tire tread, there is a technique for reducing the amount of a reinforcing material such as silica. However, at the same time, the running stability and the like are lowered, so that there is a demand for a method of reducing the rolling resistance characteristics and improving the grip performance and the running stability on a wet road surface. For the purpose of improving grip performance and running stability on a wet road surface, it is common to use a rubber composition containing a conjugated diene polymer such as butadiene rubber.

For example, Patent Document 1 describes a conjugated diene-based polymer obtained by polymerizing a conjugated diene compound using (A) an anionic polymerization initiator, or by copolymerizing a conjugated diene compound and an aromatic vinyl compound. Contains 20% by mass or more of a modified conjugated diene-based polymer obtained by reacting a compound having 4 or more alkoxy groups bonded to silyl groups and having 1 or more nitrogen atoms at the polymerization active terminal of the above. A rubber composition consisting of 30 to 70 parts by mass of a rubber component, (B) 70 to 30 parts by mass of a rubber-like polymer selected from natural rubber, high-cis polybutadiene rubber, and polyisoprene, and (C) silica. It is described that the rubber composition for tread containing a based inorganic filler is excellent in rolling resistance characteristics, processability, and running stability.

Further, Patent Document 2 mainly contains natural rubber and / or diene rubber containing isoprene rubber and butadiene rubber, a specific silane coupling agent having a mercapto group, silica, carbon black, process oil and C9 aromatic resin. A method of blending a mixture of petroleum resin and kumaron inden resin as components, a method of blending a copolymer resin of C5 distillate obtained by thermal decomposition of naphtha with diene rubber and styrene or vinyl toluene, isoprene As disclosed as a method of blending rubber and a low freezing point plasticizer, a method of blending a large amount of natural resin / synthetic resin or the like has been attempted. However, even with these methods, the grip performance on a wet road surface cannot be sufficiently improved, and there is still room for improvement. Further, Cited Document 2 describes that the rubber composition for tread can reduce rolling resistance while maintaining good running stability and grip performance on a wet road surface.

Japanese Unexamined Patent Publication No. 2013-87219 Japanese Unexamined Patent Publication No. 2012-229330

Compared to carbon black, which has a hydrophobic surface, silica has a drawback that it has a hydrophilic surface and has a low affinity with conjugated diene rubber, resulting in poor dispersibility compared to carbon black. Have. Therefore, in order to improve the dispersibility by interacting silica and rubber in the material containing silica, it is necessary to separately contain a silane coupling agent or the like. Further, when a material having a functional group having a high reactivity with silica introduced at the molecular terminal of rubber is mixed with silica particles to form a composition, the reaction with the silica particles proceeds during the kneading step, and the composition is such. The viscosity of an object increases. Due to the increase in viscosity, the composition tends to be difficult to knead, or the processability tends to be deteriorated, such as rough skin or easy sheet breakage when forming a sheet after kneading. In addition, when the above materials are vulcanized products, especially when vulcanized products containing inorganic fillers such as silica, rolling resistance characteristics, running stability, and grip performance on wet road surfaces are improved. Not enough.

Therefore, even in the rubber composition for tread described in the above document, both workability, running stability, and grip performance on a wet road surface are insufficiently compatible, and there is room for further improvement.
The present invention has been made in view of the above, and a modified conjugated diene polymer composition having good workability and excellent rolling resistance characteristics, running stability and braking performance when used in a tire is provided. The challenge is to provide.

As a result of intensive studies to solve the above problems, the present inventors have made a modified conjugated diene polymer composition containing a specific modified conjugated diene polymer, a silica-based inorganic filler, and a tack fire. However, they have found that they are excellent in workability and, when used in tires, excellent in rolling resistance characteristics, running stability and braking performance, and have completed the present invention. That is, the present invention is as follows.

[1]
100 parts by mass of a modified conjugated diene polymer having a weight average molecular weight of 20 × 10 ⁴ or more and 300 × 10 ⁴ or less and a shrinkage factor (g') of less than 0.64.
20 to 300 parts by mass of silica-based inorganic filler, and
A modified conjugated diene-based polymer composition containing 0.5 to 30 parts by mass of a tack fire.
The modified conjugated diene polymer, based on the total amount of the modified conjugated diene polymer, molecular weight of 200 × 10 ⁴ or more 500 × 10 ⁴ or less modified conjugated diene-based polymer, 0.25 wt% Including 30% by mass or more,
The modified conjugated diene polymer composition.
[2]
The modified conjugated diene-based polymer composition according to [1], further containing 0 to 70 parts by mass of at least one rubber-like polymer selected from the group consisting of natural rubber, high-cis polybutadiene rubber, and polyisoprene.
[3]
The modified conjugated diene polymer, a molecular weight of 200 × 10 ⁴ or more 500 × 10 ⁴ or less modified conjugated diene-based polymer, based on the total amount of the modified conjugated diene polymer, 1.0 wt% The modified conjugated diene-based polymer composition according to [1] or [2], which comprises 30% by mass or more.
[4]
The modified conjugated diene polymer composition according to any one of [1] to [3], wherein the modified conjugated diene polymer is represented by the following general formula (I).
In the formula (I), D ¹ represents a diene polymer chain, R ^{1 to} R ³ each independently represent a single bond or an alkylene group having 1 to 20 carbon atoms, and R ⁴ and R ⁷ are. , Each independently represent an alkyl group having 1 to 20 carbon atoms, and R ⁵ , R ⁸ and R ⁹ independently represent a hydrogen atom or an alkyl group having 1 to 20 carbon atoms, and R ⁶ and R ^{10 respectively.} Independently represent an alkylene group having 1 to 20 carbon atoms, R ¹¹ represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms, and m and x each independently represent an integer of 1 to 3 carbon atoms. Shown, x≤m, p indicates 1 or 2, y indicates an integer of 1 to 3, y≤ (p + 1), and z indicates an integer of 1 or 2. D ¹ , R ^{1 to} R ¹¹ , m, p, x, y, and z are independent of each other and may be the same or different. I is an integer of 0 to 6. Indicated, j indicates an integer of 0 to 6, k indicates an integer of 0 to 6, (i + j + k) is an integer of 3 to 10, and ((x × i) + (y × j) + (Z × k)) is an integer of 5 to 30. A is a hydrocarbon group having 1 to 20 carbon atoms or a group consisting of an oxygen atom, a nitrogen atom, a silicon atom, a sulfur atom, and a phosphorus atom. Indicates an organic group having at least one selected atom and having no active hydrogen.)
[5]
The modified conjugated diene polymer according to [4], wherein A in the formula (I) is represented by any of the following general formulas (II) to (V).
(In formula (II), B ¹ represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, a represents an integer of 1 to 10, and B ¹ represents a plurality of B ¹ independently. There.)
(In formula (III), B ² represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, B ³ represents an alkyl group having 1 to 20 carbon atoms, and a represents an integer of 1 to 10 carbon atoms. Shown. If there are multiple B ² and B ³ , they are independent of each other.)
(In formula (IV), B ⁴ represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, a represents an integer of 1 to 10. B ⁴ represents an integer of 1 to 10; and B ⁴ is independent of each other when there are a plurality of them. There.)
(In the formula (V), B ⁵ represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, a represents an integer of 1 to 10. If there are a plurality of B ^{5, they} are independent of each other. There.)
[6]
The modified conjugated diene polymer composition according to any one of [1] to [5], which is a rubber composition for a tire tread.
[7]
A tire containing a crosslinked product of the modified conjugated diene polymer composition according to any one of [1] to [6].

The modified conjugated diene polymer composition of the present invention can provide a modified conjugated diene polymer composition having good processability and excellent running stability and braking performance when used in a tire.

Hereinafter, embodiments for carrying out the present invention (hereinafter, referred to as “the present embodiment”) will be described in detail. The present invention is not limited to the following embodiments, and can be variously modified and implemented within the scope of the gist thereof.

The modified conjugated diene-based polymer composition of the present embodiment has a weight average molecular weight of 20 × 10 ⁴ or more and 300 × 10 ⁴ or less, and a contraction factor (g') of less than 0.64. It contains 100 parts by weight of the based polymer, 20 to 300 parts by mass of the silica-based inorganic filler, and 0.5 to 30 parts by weight of the tack fire. Furthermore, the modified conjugated diene-based polymer in the modified conjugated diene polymer composition of the present embodiment, the total amount of the modified conjugated diene polymer, the molecular weight is 200 × 10 ⁴ or more 500 × 10 ⁴ or less The modified conjugated diene polymer is contained in an amount of 0.25% by mass or more and 30% by mass or less.
The embodiment of the present embodiment is excellent in workability, and is excellent in the balance of rolling resistance characteristics, workability, and grip performance on a wet road surface.
Hereinafter, each component will be described.

[Modified conjugated diene polymer]
The modified conjugated diene polymer in this embodiment is
The weight average molecular weight Mw by gel permeation chromatography (GPC) is 20 × 10 ⁴ or more and 300 × 10 ⁴ or less.
Wherein the total amount of the modified conjugated diene polymer, a molecular weight of 200 × 10 ⁴ or more 500 × 10 ⁴ or less modified conjugated diene-based polymer, comprising 0.25% by weight to 30% by weight,
The contraction factor (g') is less than 0.64.

In general, a polymer having a branch tends to have a smaller molecular size when compared with a linear polymer having the same absolute molecular weight. The shrinkage factor (g') in the present embodiment is an index of the ratio of the size occupied by the branched polymer to the polymer assuming a linear polymer having the same absolute molecular weight. That is, as the degree of branching of the polymer increases, the size of the polymer molecule having branching becomes smaller than that of a polymer assuming a linear polymer having the same absolute molecular weight, and the shrinkage factor (g') ) Tends to be smaller.
Here, the "branch" is formed by directly or indirectly bonding one polymer with another polymer. Further, the "branch degree" is the number of polymers directly or indirectly bonded to each other with respect to one branch. For example, when the five conjugated diene polymer chains described below are indirectly bound to each other via a residue of a coupling agent described later (hereinafter, also referred to as a coupling residue), the degree of branching Is 5.

In this embodiment, the intrinsic viscosity is used as an index of the size of the molecule. The intrinsic viscosity of the linear polymer shall follow the relational expression of intrinsic viscosity [η] = -3.883M ^0.771 . 'Calculates a contraction factor when the absolute molecular weight of ^{100 × 10 4 ~200 × 10 4} (g shrinkage factor in the absolute molecular weight of the modified conjugated diene polymer according to the present embodiment (g)' an average value of) , The contractile factor (g') of the modified conjugated diene polymer.

The contractile factor (g') is less than 0.64, preferably 0.63 or less, more preferably 0.60 or less, still more preferably 0.59 or less, and particularly preferably 0.57 or less. It is as follows. The lower limit of the contraction factor (g') is not particularly limited and may be not more than the detection limit value, but is preferably 0.30 or more, more preferably 0.33 or more, and further preferably 0. It is .35 or more, and particularly preferably 0.45 or more. Modified conjugated diene-based polymers in which the shrinkage factor (g') is in the above range tend to be excellent in processability when made into a vulcanized product.
Since the contraction factor (g') tends to depend on the degree of branching, for example, the contraction factor (g') can be controlled using the degree of branching as an index. Specifically, when the modified conjugated diene polymer is a modified conjugated diene polymer having a branching degree of 6, the contractile factor (g') tends to be 0.59 or more and 0.63 or less. When the modified conjugated diene polymer is a modified conjugated diene polymer having a branching degree of 8, the contractile factor (g') tends to be 0.45 or more and 0.59 or less. The contraction factor (g') is measured by the method described in Examples described later.

The conjugated diene polymer chain in the present embodiment is a constituent unit of the modified conjugated diene polymer, and is, for example, a conjugated diene polymer produced by reacting a conjugated diene polymer described later with a coupling agent. It is a structural unit of origin. The conjugated diene polymer chain of the present embodiment is preferably bound to one of the coupling residues described later.
The coupling residue is a structural unit of a modified conjugated diene polymer that binds to a conjugated diene polymer chain, and is generated, for example, by reacting a conjugated diene polymer described later with a coupling agent. It is a structural unit derived from a coupling agent.

The modified conjugated diene polymer preferably has a branch and has a degree of branching of 5 or more. Further, the modified conjugated diene-based polymer has one or more coupling residues and a conjugated diene-based polymer chain that binds to the coupling residue, and the branching is the cup of 1. It is more preferable to include a branch in which 5 or more of the conjugated diene-based polymer chains are bonded to the ring residue. The structure of a modified conjugated diene polymer, which comprises a branching degree of 5 or more and a branch in which 5 or more conjugated diene polymer chains are bonded to 1 coupling residue. By doing so, the contractile factor (g') can be more reliably reduced to less than 0.64.

The degree of branching of the modified conjugated diene polymer is more preferably 6 or more. The modified conjugated diene-based polymer has one or more coupling residues and a conjugated diene-based polymer chain that binds to the coupling residues, and further, the branching remains the coupling of 1. It is more preferable to include a branch in which 6 or more of the conjugated diene polymer chains are bonded to the group. The structure of a modified conjugated diene polymer, which comprises a branching degree of 6 or more and a branch in which 6 or more conjugated diene polymer chains are bonded to 1 coupling residue. By doing so, the contractile factor (g') can be reduced to 0.63 or less.

The degree of branching of the modified conjugated diene polymer is more preferably 7 or more, and even more preferably 8 or more. The upper limit of the degree of branching is not particularly limited, but is preferably 18 or less from the viewpoint of ease of manufacture. Further, the modified conjugated diene-based polymer has one or more coupling residues and a conjugated diene-based polymer chain that binds to the coupling residues, and further, the said cup having the branch of 1. It is more preferable to include a branch in which 7 or more of the conjugated diene polymer chains are bonded to the ring residue, and 8 or more of the conjugated diene polymer chains are bound to 1 of the coupling residue. It is even more preferred to include a branch to which the is attached. The number of conjugated diene-based polymer chains bound to one coupling residue can be confirmed from the value of the contractile factor (g'). The structure of a modified conjugated diene polymer, which comprises a branching degree of 8 or more and a branch in which 8 or more conjugated diene polymer chains are bonded to 1 coupling residue. By doing so, the contractile factor (g') can be reduced to 0.59 or less.

Further, the modified conjugated diene polymer preferably has a nitrogen atom and a silicon atom. As a result, the processability of the vulcanized product tends to be superior, and the low hysteresis loss property of the vulcanized product, running stability, and grip performance on a wet road surface tend to be excellent. The fact that the modified conjugated diene polymer has a nitrogen atom can be confirmed by the presence or absence of adsorption on a specific column as described in Examples. Further, it can be confirmed by metal analysis that the modified conjugated diene polymer has a silicon atom as described in Examples.

It is more preferable that at least one silicon atom contained in the modified conjugated diene polymer constitutes an alkoxysilyl group or silanol group having 1 to 20 carbon atoms. As a result, the silica dispersibility becomes excellent. Further, from the viewpoint that hydrogen halide can be generated by reacting with air, the modified conjugated diene polymer preferably does not have a halogen.

It is preferable that at least one end of the 5 or more conjugated diene-based polymer chains is bonded to the silicon atom of the coupling residue. As a result, the silica dispersibility becomes better. In this case, the ends of the plurality of conjugated diene-based polymer chains may be bonded to one silicon atom. Further, the terminal of the conjugated diene polymer chain and an alkoxy group or a hydroxyl group having 1 to 20 carbon atoms are bonded to one silicon atom, and as a result, the one silicon atom is an alkoxysilyl having 1 to 20 carbon atoms. It may constitute a group or a silanol group. The coupling residue preferably has no halogen from the viewpoint that it can react with air to generate hydrogen halide.

The modified conjugated diene polymer or the conjugated diene polymer described later improves heat resistance and weather resistance, and prevents deterioration when processed at a high temperature and deterioration when a hydrocarbon compound is used. Further hydrogenation in an inert solvent can convert all or part of the double bond to saturated hydrocarbons. As a result, the modified conjugated diene polymer of the present embodiment exhibits more excellent performance in various applications such as automobile applications. More specifically, the hydrogenation rate of the unsaturated double bond based on the conjugated diene compound can be arbitrarily selected depending on the intended purpose and is not particularly limited. When used as a vulcanized product, it is preferable that the double bond of the conjugated diene portion remains partially. From the above viewpoint, the hydrogenation ratio of the conjugated diene portion in the conjugated diene polymer is preferably 3.0% or more and 70% or less, more preferably 5.0 or more and 65% or less, and 10%. It is more preferably 60% or more. In particular, selective hydrogenation of vinyl groups tends to improve heat resistance and weather resistance. The hydrogenation rate can be determined by a nuclear magnetic resonance apparatus (NMR).

The modified conjugated diene-based copolymer may be an oil-extended polymer containing a spreading oil. The modified conjugated diene-based copolymer, whether non-oil-extended or oil-extended, has workability when it is made into a rubber vulcanized product and grip performance on a wet road surface when it is made into a vulcanized product. From the above viewpoint, the Mooney viscosity measured at 100 ° C. is preferably 20 or more and 100 or less, and more preferably 30 or more and 80 or less. The Mooney viscosity is measured by the method described in Examples described below.

The weight average molecular weight Mw by gel permeation chromatography (GPC) of the modified conjugated diene polymer is a 20 × 10 ⁴ or more, preferably 50 × 10 ⁴ or more, more preferably 64 × 10 ⁴ or more, still more preferably 80 × 10 ⁴ or more. By weight average molecular weight Mw is 20 × 10 ⁴ or more, excellent grip performance of at rolling resistance and wet road surface upon the vulcanizates.
Further, the weight average molecular weight Mw is a 300 × 10 ⁴ or less, preferably 250 × 10 ⁴ or less, preferably 180 × 10 ⁴ or less, more preferably 0.99 × 10 ⁴ or less. By weight average molecular weight Mw is 300 × 10 ⁴ or less, excellent workability at the time of the vulcanizate.
The weight average molecular weight Mw of the modified conjugated diene polymer and the conjugated diene polymer described later is measured by the method described in Examples described later.

Modified conjugated diene polymer, based on the total amount of the modified conjugated diene polymer (100 mass%), the modified conjugated diene polymer molecular weight of 200 × 10 ⁴ or more 500 × 10 ⁴ or less (hereinafter, Also referred to as "specific high molecular weight component") is contained in an amount of 0.25% by mass or more and 30% by mass or less. As a result, it is excellent in rolling resistance characteristics when made into a vulcanized product and grip performance on a wet road surface. The modified conjugated diene polymer contains a specific high molecular weight component, preferably 1.0% by mass or more, more preferably 1.75% by mass or more, still more preferably 2.0% by mass or more, and even more. It preferably contains 2.15% by mass or more, and even more preferably 2.5% by mass or more. Further, the modified conjugated diene polymer contains a specific high molecular weight component, preferably 28% by mass or less, more preferably 25% by mass or less, still more preferably 20% by mass or less, still more preferably 18% by mass. Including the following.

Further, "molecular weight" in the "modified conjugated diene-based polymer molecular weight of 200 × 10 ⁴ or more 500 × 10 ⁴ or less", obtained by GPC (gel permeation chromatography), is the standard polystyrene molecular weight .. In order to obtain a modified conjugated diene-based polymer in which the content of a specific high molecular weight component is in the range of 0.25% by mass or more and 30% by mass or less, the reaction conditions in the polymerization step and the reaction step described later must be controlled. Is preferable. For example, control of the reaction conditions in the polymerization step includes adjusting the amount of the organic monolithium compound used as a polymerization initiator, which will be described later. Further, as the control of the reaction conditions in the polymerization step, a method having a residence time distribution, that is, a method of expanding the time distribution of the growth reaction is used in both the continuous type and the batch type polymerization modes in the polymerization step described later. Suitable.

As a specific method in the continuous polymerization mode, for example, a tank reactor with a stirrer is preferably used as a backmix reactor in which the reactor is vigorously mixed, and more preferably as a complete mixing reactor. , A method of partially recirculating a tubular reactor; a method of providing a polymerization initiator feed location in the middle of the polymerizer in addition to the monomer inlet or its vicinity; and a tank type And a method of combining the tubular type; etc. These methods are methods in which the residence time distribution is increased and a polymer component having a long residence time is used as a high molecular weight component.

Further, as a specific method in the batch type polymerization mode, for example, a method of continuously or intermittently feeding the polymerization initiator from the start of the polymerization to the middle of the polymerization, or at the start of the polymerization and / or during the polymerization. A method of continuously or intermittently feeding is preferably mentioned. In these methods, the polymer polymerized from the start of polymerization in which the polymerization initiator is first fed becomes a high molecular weight component, and a difference in molecular weight is generated between the polymer and the polymer started later. More specifically, if the amount of the polymerization initiator corresponding to the target molecular weight is continuously fed to the monomer from, for example, a conversion rate of 0% to 95%, the monomer has an expanded molecular weight distribution. It tends to be a polymer. By using the above-mentioned method, the active ratio of the living end of the conjugated diene polymer before the reaction step tends to be high, and the coupling rate after coupling, that is, the modified conjugated diene polymer having a high modification rate There is also a tendency to obtain. Among these methods, a tank-type reactor with a stirrer is more preferable, and a backmix reactor of a type in which the reactor is vigorously mixed with the stirrer is used. The temperature change from the polymerization step to the addition of the coupling agent is preferably 10 ° C. or lower, more preferably 5 ° C. or lower.

In addition to the control of the reaction conditions in the above-mentioned polymerization step, the control of the reaction conditions in the modification step is, for example, from the viewpoint of obtaining a modified conjugated diene polymer containing 1.0% by mass or more of a specific high molecular weight component, for example. The reaction time is preferably 10 seconds or longer, more preferably 30 seconds or longer. The time from the end of the polymerization step to the start time of the reaction step is preferably shorter, but more preferably 5 minutes or less. By doing so, a high coupling rate and a high modification rate are likely to be obtained, and a high molecular weight component tends to be easily obtained. Further, as the number of functional groups of the coupling agent increases, the degree of branching in the obtained modified conjugated diene polymer deviates from the desired value when the amount of the coupling agent added cannot be controlled within a desired range in the reaction step. It will be easier. Therefore, in order to generate a predetermined amount of a specific high molecular weight component, it is preferable to appropriately control the amount of the coupling agent added. In order to appropriately control the amount of the coupling agent added, for example, a method of diluting the coupling agent and then adding the coupling agent is preferable. The dilution concentration at that time is preferably 0.1 mmol / L to 1.1 mol / L, and more preferably 1 mmol / L to 0.75 mol / L. When the deviation of the addition amount is the same, the deviation between the number of moles of the conjugated diene polymer and the number of moles of the coupling agent tends to be smaller when diluted. Further, the water content of the solvent to be diluted is preferably 100 mass ppm or less, more preferably 50 mass ppm or less, still more preferably 30 mass ppm or less, still more preferably 10 mass ppm or less. When the water content of the solvent to be diluted is 100% by mass or less, the coupling agent reacts with water and the functional groups in the coupling agent are reduced, so that the molar amount of the conjugated diene polymer is reduced. The deviation between the number and the number of moles of the coupling agent can be suppressed, and a high molecular weight component tends to be easily obtained.

In the modified conjugated diene polymer, the molecular weight distribution (Mw / Mn) represented by the ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is preferably 1.6 or more and 3.0 or less. Modified conjugated diene-based polymers having a molecular weight distribution in this range tend to be more excellent in processability when made into a vulcanized product, and tend to be more excellent in grip performance on a wet road surface when made into a vulcanized product.
The number average molecular weight Mn, the weight average molecular weight Mw, the molecular weight distribution, and the content of a specific high molecular weight component with respect to the modified conjugated diene polymer and the conjugated diene polymer described later are measured by the methods described in Examples described later. ..

The modified conjugated diene polymer in the present embodiment is preferably represented by the following general formula (I).

In the formula (I), D ¹ represents a diene-based polymer chain, and the weight average molecular weight of the diene-based polymer chain is preferably 10 × 10 ^{4 to} 100 × 10 ⁴ . R ^{1 to} R ³ each independently represent a single bond or an alkylene group having 1 to 20 carbon atoms, and R ⁴ and R ⁷ each independently represent an alkyl group having 1 to 20 carbon atoms, and R ⁵ ,. R ⁸ and R ⁹ each independently represent a hydrogen atom or an alkyl group having 1 to 20 carbon atoms, and R ⁶ and R ¹⁰ each independently represent an alkylene group having 1 to 20 carbon atoms, and R ¹¹ Indicates a hydrogen atom or an alkyl group having 1 to 20 carbon atoms. m and x represent integers 1-3, x ≦ m, p represents 1 or 2, y represents an integer 1-3, y ≦ (p + 1), z is 1 Or an integer of 2. When there are a plurality of D ¹ , R ^{1 to} R ¹¹ , m, p, x, y, and z are independent of each other and may be the same or different. i indicates an integer of 0 to 6, j indicates an integer of 0 to 6, k indicates an integer of 0 to 6, (i + j + k) is an integer of 3 to 10, and ((xxi) + ( y × j) + (z × k)) is an integer of 5 to 30. A has a hydrocarbon group having 1 to 20 carbon atoms or at least one atom selected from the group consisting of an oxygen atom, a nitrogen atom, a silicon atom, a sulfur atom, and a phosphorus atom, and has active hydrogen. Indicates an organic group that does not have.

The hydrocarbon groups indicated by A include saturated, unsaturated, aliphatic, and aromatic hydrocarbon groups. The organic group having no active hydrogen is an organic group that inactivates the active terminal of the conjugated diene polymer. Examples of such an organic group include a functional group having an active hydrogen such as a hydroxyl group (-OH), a secondary amino group (> NH), a primary amino group (-NH ₂ ), and a sulfhydryl group (-SH). It is an organic group that does not have a group. The modified conjugated diene polymer represented by the formula (I) tends to be superior in processability when it is made into a vulcanized product, and it depends on the rolling resistance characteristics when it is made into a vulcanized product and the grip performance on a wet road surface. It tends to be excellent.

In the formula (I) of the modified conjugated diene polymer in the present embodiment, A is preferably represented by any of the following general formulas (II) to (V).

In formula (II), B ¹ represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, and a represents an integer of 1 to 10. When there are a plurality of B ¹ , they are independent of each other.

In formula (III), B ² represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, B ³ represents an alkyl group having 1 to 20 carbon atoms, and a represents an integer of 1 to 10 carbon atoms. .. When there are a plurality of B ² and B ³ , they are independent of each other.

In formula (IV), B ⁴ represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, and a represents an integer of 1 to 10. When there are a plurality of B ⁴ , they are independent of each other.

In formula (V), B ⁵ represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, and a represents an integer of 1 to 10. B ^5, when there are a plurality, they are each independently.

When A is represented by any of the formulas (II) to (V), it tends to be more excellent in processability when it is made into a vulcanized product, which is the effect of this embodiment, and when it is made into a vulcanized product It tends to be superior in rolling resistance characteristics and grip performance on wet road surfaces. In addition, it tends to be easily available in practice.

[Method for producing modified conjugated diene polymer]
The method for producing a modified conjugated diene polymer is a polymerization step in which an organic monolithium compound is used as a polymerization initiator and at least the conjugated diene compound is polymerized to obtain a conjugated diene polymer, and an active terminal of the conjugated diene polymer. It has a reaction step of reacting a reactive compound having five or more functionalities (hereinafter, also referred to as “coupling agent”). As the coupling agent, it is preferable to react a reactive compound having five or more functionalities having a nitrogen atom and a silicon atom. The reaction step is preferably a reaction step in which the compound represented by the following general formula (VI) is reacted with the active terminal of the conjugated diene polymer.

In formula (VI), R ^{12 to} R ¹⁴ each independently represent a single bond or an alkylene group having 1 to 20 carbon atoms, and R ^{15 to} R ¹⁸ and R ²⁰ each independently represent 1 to 1 carbon atoms. 20 alkyl groups are shown, R ¹⁹ and R ²² each independently represent an alkylene group having 1 to 20 carbon atoms, and R ²¹ represents an alkyl group having 1 to 20 carbon atoms or a trialkylsilyl group. m represents an integer of 1 to 3 and p represents 1 or 2. R ^{12 to} R ²² , m, and p when there are a plurality of them are independent of each other and may be the same or different. i indicates an integer of 0 to 6, j indicates an integer of 0 to 6, k indicates an integer of 0 to 6, and (i + j + k) is an integer of 3 to 10. A has a hydrocarbon group having 1 to 20 carbon atoms or at least one atom selected from the group consisting of an oxygen atom, a nitrogen atom, a silicon atom, a sulfur atom, and a phosphorus atom, and has no active hydrogen. Indicates an organic group.

The hydrocarbon groups indicated by A include saturated, unsaturated, aliphatic, and aromatic hydrocarbon groups. The organic group having no active hydrogen is an organic group that inactivates the active terminal of the conjugated diene polymer. Examples of such an organic group include a functional group having an active hydrogen such as a hydroxyl group (-OH), a secondary amino group (> NH), a primary amino group (-NH ₂ ), and a sulfhydryl group (-SH). It is an organic group that does not have a group.

[Polymerization process]
The polymerization step is a step of polymerizing at least a conjugated diene compound using an organic monolithium compound as a polymerization initiator to obtain a conjugated diene-based polymer. In the polymerization step, polymerization is preferably carried out by a growth reaction by a living anionic polymerization reaction, whereby a conjugated diene-based polymer having an active terminal can be obtained, and a modified diene-based polymer having a high modification rate can be obtained. There is a tendency.

The conjugated diene-based polymer is obtained by polymerizing at least a conjugated diene compound, and is obtained by copolymerizing both a conjugated diene compound and a vinyl-substituted aromatic compound, if necessary. The conjugated diene compound is not particularly limited as long as it is a polymerizable monomer, and for example, 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 3-. Examples include methyl-1,3-pentadiene, 1,3-hexadiene, and 1,3-heptadiene. Among these, 1,3-butadiene and isoprene are preferable from the viewpoint of easy industrial availability. These may be used alone or in combination of two or more.

The vinyl-substituted aromatic compound is not particularly limited as long as it is a monomer copolymerizable with the conjugated diene compound, but a monovinyl aromatic compound is preferable. Monovinyl aromatic compounds include, but are not limited to, styrene, p-methylstyrene, α-methylstyrene, vinylethylbenzene, vinylxylene, vinylnaphthalene, and diphenylethylene. Among these, styrene is preferable from the viewpoint of easy industrial availability. These may be used alone or in combination of two or more.

If allenes, acetylenes, etc. are contained as impurities in the conjugated diene compound and / or the vinyl-substituted aromatic compound, the reaction in the reaction step described later may be hindered. Therefore, the above impurities can be reacted with the organometallic compound before the polymerization reaction in advance in a mixed solution with a hydrocarbon solvent such as saturated hydrocarbons and aromatic saturated hydrocarbons. Examples of allenes include propadiene and 1,2-butadiene. Examples of acetylenes include ethylacetylene and vinylacetylene.

The conjugated diene-based polymer may be a random copolymer or a block copolymer. In order to make the conjugated diene polymer into a rubber-like polymer, it is preferable to use 40% by mass or more of the conjugated diene compound, and 55% by mass or more, based on the entire monomer of the conjugated diene polymer. More preferred.

The random copolymer is not limited to the following, but is, for example, a random copolymer composed of two or more kinds of conjugated diene compounds such as a butadiene-isoprene random copolymer, a butadiene-styrene random copolymer, and an isoprene-. Examples thereof include a styrene random copolymer and a random copolymer composed of a conjugated diene of a butadiene-isoprene-styrene random copolymer and a vinyl-substituted aromatic compound. The composition distribution of each monomer in the copolymer chain is not particularly limited, for example, a completely random copolymer having a composition close to a statistically random composition, and a tapered (gradient) random composition in which the composition is distributed in a tapered shape. Copolymers can be mentioned. The bonding mode of the conjugated diene, that is, the composition such as 1,4-bonding and 1,2-bonding, may be uniform or may be distributed.

The block copolymer is not limited to the following, but for example, a type 2 block copolymer composed of two blocks (diblock), a type 3 block copolymer composed of three blocks (triblock), and the like. Examples thereof include a 4-type block copolymer (tetrablock) composed of four pieces. The polymer constituting one block may be a polymer composed of one kind of monomer or a copolymer composed of two or more kinds of monomers. For example, a polymer block composed of 1,3-butadiene is represented by "B", a polymer of 1,3-butadiene and isoprene is represented by "B / I", and a polymer of 1,3-butadiene and styrene. Is represented by "B / S", and a polymer block made of styrene is represented by "S". A BB / I2 type block copolymer, a BB / S2 type block copolymer, and an SB2 type block. It is represented by a copolymer, a BB / SS3 type block copolymer, an SBS3 type block copolymer, an SBSB4 type block copolymer and the like.

In the above equation, the boundaries of each block do not necessarily have to be clearly distinguished. Further, when one polymer block is a copolymer composed of two types of monomers A and B, A and B in the block may be uniformly distributed or may be distributed in a tapered shape. Good.

At least an organic monolithium compound is used as the polymerization initiator. The organic monolithium compound is not limited to the following, and examples thereof include low molecular weight compounds and organic monolithium compounds of solubilized oligomers. In addition, examples of the organic monolithium compound include a compound having a carbon-lithium bond, a compound having a nitrogen-lithium bond, and a compound having a tin-lithium bond in the bonding mode of the organic group and the lithium thereof.

The amount of the organic monolithium compound used as the polymerization initiator is preferably determined by the molecular weight of the target conjugated diene polymer or modified conjugated diene polymer. The amount of a monomer such as a conjugated diene compound used with respect to the amount of the polymerization initiator used tends to be related to the degree of polymerization, that is, the number average molecular weight and / or the weight average molecular weight. Therefore, in order to increase the molecular weight, it is preferable to adjust to reduce the amount of the polymerization initiator, and in order to decrease the molecular weight, it is preferable to adjust to increase the amount of the polymerization initiator.

The organic monolithium compound is preferably an alkyllithium compound having a substituted amino group or dialkylaminolithium from the viewpoint of being used in one method of introducing a nitrogen atom into a conjugated diene polymer. In this case, a conjugated diene polymer having a nitrogen atom composed of an amino group at the polymerization initiation terminal can be obtained.
The substituted amino group is an amino group having no active hydrogen or having a structure in which active hydrogen is protected. The alkyllithium compound having an amino group having no active hydrogen is not limited to the following, and for example, 3-dimethylaminopropyl lithium, 3-diethylaminopropyl lithium, 4- (methylpropylamino) butyl lithium, and 4 -Hexamethylene iminobutyl lithium and the like can be mentioned. The alkyllithium compound having an amino group having a structure in which active hydrogen is protected is not limited to the following, and examples thereof include 3-bistrimethylsilylaminopropyllithium and 4-trimethylsilylmethylaminobutyllithium.

The dialkylaminolithium is not limited to the following, and includes, for example, lithium dimethylamide, lithium diethylamide, lithium dipropylamide, lithium dibutylamide, lithium di (n-hexylamide), lithium diheptylamide, lithium diisopropylamide, and lithium dioctyl. Amide, Lithiumdi (2-ethylhexylamide), Lithiumdidecylamide, Lithiumethylpropylamide, Lithiumethylbutylamide, Lithiumethylbenzylamide, Lithiummethylphenethylamide, Lithiumhexamethyleneimide, Lithiumpyrrolidide, Lithiumpiperidide, Lithium heptamethyleneimide, lithium morpholide, 1-lithioazacyclooctane, 6-lithio-1,3,3-trimethyl-6-azabicyclo [3.2.1] octane, and 1-lithio-1,2, Examples thereof include 3,6-tetrahydropyridine.

The organic monolithium compound having these substituted amino groups is an oligomer of organic monolithium solubilized by reacting a small amount of a polymerizable monomer such as 1,3-butadiene, isoprene, or styrene. It can also be used as a compound.
The organic monolithium compound is preferably an alkyllithium compound from the viewpoint of easy industrial availability and easy control of the polymerization reaction. In this case, a conjugated diene-based polymer having an alkyl group at the polymerization initiation terminal can be obtained. Alkyllithium compounds include, but are not limited to, n-butyllithium, sec-butyllithium, tert-butyllithium, n-hexyllithium, benzyllithium, phenyllithium, and stillbenlithium. As the alkyllithium compound, n-butyllithium and sec-butyllithium are preferable from the viewpoint of easy industrial availability and easy control of the polymerization reaction.

These organic monolithium compounds may be used alone or in combination of two or more. In addition, it may be used in combination with other organometallic compounds. Examples of the organometallic compound include alkaline earth metal compounds, other alkali metal compounds, and other organometallic compounds. The alkaline earth metal compound is not limited to the following, and examples thereof include an organic magnesium compound, an organic calcium compound, and an organic strontium compound. Also included are compounds of alkaline earth metals alcoxides, sulfonates, carbonates, and amides. Examples of the organic magnesium compound include dibutylmagnesium and ethylbutylmagnesium. Examples of other organometallic compounds include organoaluminum compounds.

In the polymerization step, the polymerization reaction mode is not limited to the following, and examples thereof include a batch type (also referred to as “batch type”) and a continuous type polymerization reaction mode. In the continuous polymerization reaction mode, one or two or more linked reactors can be used. As the continuous reactor, for example, a tank type or tube type reactor with a stirrer is used. In the continuous system, preferably, the monomer, the inert solvent, and the polymerization initiator are continuously fed to the reactor to obtain a polymer solution containing the polymer in the reactor, and the polymer solution is continuously weighted. The coalesced solution is drained. As the batch reactor, for example, a tank type reactor with a stirrer is used. In the batch polymerization reaction mode, preferably, the monomer, the inert solvent, and the polymerization initiator are fed, and if necessary, the monomer is continuously or intermittently added during the polymerization in the reactor. A polymer solution containing the polymer is obtained, and the polymer solution is discharged after the completion of the polymerization. In the present embodiment, in order to obtain a conjugated diene-based polymer having an active terminal at a high ratio, the polymer can be continuously discharged and subjected to the next reaction in a short time, which is a continuous polymerization reaction mode. Is preferable.

The polymerization step is preferably carried out in an inert solvent. Examples of the solvent include hydrocarbon solvents such as saturated hydrocarbons and aromatic hydrocarbons. Specific hydrocarbon solvents are not limited to the following, but are, for example, aliphatic hydrocarbons such as butane, pentane, hexane and heptane; alicyclic groups such as cyclopentane, cyclohexane, methylcyclopentane and methylcyclohexane. Hydrocarbons; examples include hydrocarbons composed of aromatic hydrocarbons such as benzene, toluene and xylene and mixtures thereof. By treating impurities such as allenes and acetylenes with an organometallic compound before subjecting them to a polymerization reaction, a conjugated diene-based polymer having a high concentration of active terminals tends to be obtained, and modification with a high modification rate. It is preferable because the conjugated diene polymer (a1) tends to be obtained.

In the polymerization step, a polar compound may be added. The aromatic vinyl compound can be randomly copolymerized with the conjugated diene compound, and tends to be used as a vinylizing agent for controlling the microstructure of the conjugated diene portion. It also tends to be effective in promoting the polymerization reaction.
Polar compounds are not limited to the following, but are not limited to, for example, tetrahydrofuran, diethyl ether, dioxane, ethylene glycol dimethyl ether, ethylene glycol dibutyl ether, diethylene glycol dimethyl ether, diethylene glycol dibutyl ether, dimethoxybenzene, 2,2-bis (2-oxolanyl). ) Ethers such as propane; tertiary amine compounds such as tetramethylethylenediamine, dipiperidinoethane, trimethylamine, triethylamine, pyridine, quinuclidine; potassium-tert-amylate, potassium-tert-butyrate, sodium-tert-butyrate, Alkali metal alkoxide compounds such as sodium amylate; phosphine compounds such as triphenylphosphine can be used. These polar compounds may be used alone or in combination of two or more.

The amount of the polar compound used is not particularly limited and can be selected depending on the intended purpose and the like, but is preferably 0.01 mol or more and 100 mol or less with respect to 1 mol of the polymerization initiator. Such a polar compound (vinyl agent) can be used in an appropriate amount as a regulator of the microstructure of the polymer-conjugated diene moiety, depending on the desired amount of vinyl bond. Many polar compounds have a randomizing effect that is effective in the copolymerization of the conjugated diene compound and the aromatic vinyl compound at the same time, and tend to be used as an agent for adjusting the distribution of the aromatic vinyl compound and the amount of styrene block. It is in. As a method for randomizing the conjugated diene compound and the aromatic vinyl compound, for example, as described in JP-A-59-140211, the total amount of styrene and a part of 1,3-butadiene are copolymerized. A method of initiating the polymerization reaction and intermittently adding the remaining 1,3-butadiene during the copolymerization reaction may be used.

In the polymerization step, the polymerization temperature is preferably a temperature at which living anionic polymerization proceeds, more preferably 0 ° C. or higher, and even more preferably 120 ° C. or lower, from the viewpoint of productivity. Within such a range, the amount of reaction of the coupling agent to the active terminal after the completion of polymerization tends to be sufficiently secured. Even more preferably, it is 50 ° C. or higher and 100 ° C. or lower.

The conjugated diene-based polymer (hereinafter, also simply referred to as “conjugated diene-based polymer”) obtained in the polymerization step before the reaction step preferably has a Mooney viscosity of 10 or more and 90 or less measured at 110 ° C., and more. It is preferably 15 or more and 85 or less, and more preferably 20 or more and 60 or less. Within this range, the modified conjugated diene polymer used in the present embodiment tends to be excellent in processability and grip performance on a wet road surface.

The amount of bound conjugated diene in the conjugated diene polymer or the modified conjugated diene polymer is not particularly limited, but is preferably 40% by mass or more and 100% by mass or less, and 55% by mass or more and 80% by mass or less. Is more preferable. The amount of bound aromatic vinyl in the conjugated diene polymer or modified conjugated diene polymer used in the present embodiment is not particularly limited, but is 0% by mass or more and 60% by mass or less from the viewpoint of rolling resistance. It is preferably 20% by mass or more and 45% by mass or less. When the amount of the bonded conjugated diene and the amount of the bonded aromatic vinyl are in the above ranges, the rolling resistance characteristics and the grip performance on a wet road surface tend to be superior when the modified conjugated diene polymer composition is used as a vulcanized product. Here, the amount of bound aromatic vinyl can be measured by the ultraviolet absorption of the phenyl group, and the amount of bound conjugated diene can also be determined from this. Specifically, the measurement is performed according to the method described in Examples described later.

The amount of vinyl bond in the conjugated diene bond unit in the modified conjugated diene polymer is not particularly limited, but is preferably 10 mol% or more and 75 mol% or less, and more preferably 20 mol% or more and 65 mol% or less. preferable. When the vinyl bond amount is in the above range, the rolling resistance characteristics and the grip performance on a wet road surface tend to be excellent when the modified conjugated diene polymer composition is used as a vulcanized product. Here, when the modified diene polymer is a copolymer of butadiene and styrene, the amount of vinyl bond in the butadiene bond unit is determined by the Hampton method (RR Hampton, Analytical Chemistry, 21, 923 (1949)). (1,2-bonding amount) can be obtained. Specifically, the measurement is performed by the method described in Examples described later.

Regarding the microstructure of the modified conjugated diene polymer, the amount of each bond in the modified conjugated diene polymer is within the above range, and the glass transition temperature of the modified conjugated diene polymer is −45 ° C. or higher and −15 ° C. or higher. When it is in the following range, it tends to be possible to obtain a pulverized product having more excellent rolling resistance characteristics. Regarding the glass transition temperature, according to ISO 22768: 2006, the DSC curve is recorded while raising the temperature in a predetermined temperature range, and the peak top (Inflection point) of the DSC differential curve is defined as the glass transition temperature. Specifically, the measurement is performed by the method described in Examples described later.

When the modified conjugated diene-based polymer is a conjugated diene-aromatic vinyl copolymer, it is preferable that the number of blocks in which 30 or more aromatic vinyl units are linked is small or absent. More specifically, when the copolymer is a butadiene-styrene copolymer, the copolymer weight is increased by the method of Kolthoff (the method described in IM KOLTHOFF, et al., J. Polym. Sci. 1, 429 (1946)). In a known method of decomposing a coalescence and analyzing the amount of polystyrene insoluble in methanol, blocks in which 30 or more aromatic vinyl units are linked are preferably 5.0% by mass or less based on the total amount of the copolymer. , More preferably 3.0% by mass or less.

When the conjugated diene-based polymer is a conjugated diene-aromatic vinyl copolymer, it is preferable that the aromatic vinyl unit is present alone in a large proportion. Specifically, when the copolymer is a butadiene-styrene copolymer, the copolymer is decomposed by a method by ozone decomposition known as the method of Tanaka et al. (Polymer, 22, 1721 (1981)). When the styrene chain distribution was analyzed by GPC, the amount of isolated styrene was 40% by mass or more and the number of chained styrene structures having 8 or more styrene chains was 5.0% by mass or less with respect to the total amount of bound styrene. Is desirable. In this case, the obtained vulcanized rubber has particularly excellent rolling resistance characteristics.

[Reaction process]
In the reaction step, a reactive compound having five or more functions (hereinafter, also referred to as “coupling agent”) is reacted with the active terminal of the conjugated diene polymer, and the coupling residue is reacted with five or more molecules of conjugated diene. The modified conjugated diene-based polymer in the present embodiment in which the system polymer is bonded can be obtained. It is preferable to react a reactive compound having five or more functionalities having a nitrogen atom and a silicon atom.

The coupling agent used in the reaction step may have any structure as long as it is a reactive compound having five or more functionalities, but preferably a reactive compound having five or more functionalities having a nitrogen atom and a silicon atom is preferable. It preferably has three silicon-containing functional groups. A more preferable coupling agent is one in which at least one silicon atom constitutes an alkoxysilyl group or silanol group having 1 to 20 carbon atoms, and more preferably the coupling agent is represented by the above formula (VI). It is a compound.

The alkoxysilyl group contained in the coupling agent reacts with, for example, the active terminal of the conjugated diene polymer to dissociate alkoxylithium, and the terminal of the conjugated diene polymer chain and the silicon of the coupling residue are bonded. Tends to form. The value obtained by subtracting the number of SiORs reduced by the reaction from the total number of SiORs contained in one molecule of the coupling agent is the number of alkoxysilyl groups contained in the coupling residue. Further, the azasila cycle group contained in the coupling agent forms a> N-Li bond and a bond between the terminal of the conjugated diene polymer and the silicon of the coupling residue. The> N-Li bond tends to be> NH and LiOH easily due to water or the like at the time of finishing. Further, in the coupling agent, the alkoxysilyl group remaining unreacted tends to easily become silanol (Si-OH group) due to water or the like at the time of finishing.

In the reaction step, when one silicon atom has three alkoxy groups, that is, one mol of trialkoxysilane group is reacted with the active end of 3 mol of conjugated diene polymer, up to 2 mol of conjugate is used. Reactions with diene-based polymers occur, but 1 mol of alkoxy group tends to remain unreacted, which means that 1 mol of conjugated diene-based polymer remains unreacted as an unreacted polymer. It can be confirmed by doing. By reacting a large number of alkoxy groups, it tends to be possible to suppress a large change in polymer viscosity due to a condensation reaction occurring during finishing and storage. In particular, 1 mol of the trialkoxysilane group reacted with 2 mol of the conjugated diene copolymer in the modified conjugated diene copolymer having 3 or more, that is, a degree of branching of 6 or more, and other reactions. Condensation reactions tend to be suppressed when possible alkoxy groups are not present in the modified conjugated diene copolymer.

Coupling agents are not limited to the following, but are, for example, tris (3-trimethoxysilylpropyl) amine, tris (3-triethoxysilylpropyl) amine, tris (3-tripropoxysilylpropyl) amine, and bis. (3-Trimethoxysilylpropyl)-[3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl] amine, tetrax (3-trimethoxysilylpropyl) -1,3-propanediamine, Tris (3-trimethoxysilylpropyl)-[3- (1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl] -1,3-propanediamine, tris (3-trimethoxysilylpropyl) )-[3- (1-Methoxy-2-methyl-1-sila-2-azacyclopentane) propyl] -1,3-propanediamine, bis (3-triethoxysilylpropyl)-[3- (2,2) 2-Diethoxy-1-aza-2-silacyclopentane) propyl]-[3- (1-ethoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl] -1,3-propanediamine, tetrakis (3-Trimethoxysilylpropyl) -1,3-bisaminomethylcyclohexane, Tris (3-trimethoxysilylpropyl)-[3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl] -1,3-bisaminomethylcyclohexane, tetrax (3-trimethoxysilylpropyl) -1,6-hexamethylenediamine, pentax (3-trimethoxysilylpropyl) -diethylenetriamine, tris (3-trimethoxysilylpropyl)- Methyl-1,3-propanediamine, tetrax [3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl] silane, bis (3-trimethoxysilylpropyl) -bis [3- (2) , 2-Dimethoxy-1-aza-2-silacyclopentane) propyl] Silane, Tris [3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl]-(3-trimethoxysilylpropyl) ) Silane, Tris [3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl]-[3- (1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl ] Silane, 3-Tris [2- (2,2-dimethoxy-1-aza-2-silacyclopentane) ethoxy] Cyril- 1-trimethoxysilylpropane, 1- [3- (1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl] -3,4,5-tris (3-trimethoxysilylpropyl)- Cyclohexane, 1- [3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl] -3,4,5-tris (3-trimethoxysilylpropyl) -cyclohexane, 3,4,5 -Tris (3-trimethoxysilylpropyl) -cyclohexyl- [3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl] ether, (3-trimethoxysilylpropyl) phosphate, bis (3) -Trimethoxysilylpropyl)-[3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl] phosphate, bis [3- (2,2-dimethoxy-1-aza-2-silacyclo) Examples thereof include pentane) propyl]-(3-trimethoxysilylpropyl) phosphate and tris [3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl] phosphate.

The reaction temperature in the reaction step is preferably the same temperature as the polymerization temperature of the conjugated diene polymer, more preferably 0 ° C. or higher and 120 ° C. or lower, and further preferably 50 ° C. or higher and 100 ° C. or lower. The temperature change from the polymerization step to the addition of the coupling agent is preferably 10 ° C. or lower, more preferably 5 ° C. or lower.
The reaction time in the reaction step is preferably 10 seconds or longer, more preferably 30 seconds or longer. The time from the end of the polymerization step to the start of the reaction step is preferably shorter, but more preferably within 5 minutes. By doing so, a high coupling rate and a high denaturation rate tend to be obtained.

The mixing in the reaction step may be either mechanical stirring, stirring with a static mixer, or the like. When the polymerization step is a continuous type, it is preferable that the reaction step is also a continuous type. As the reactor in the reaction step, for example, a tank type or tube type reactor with a stirrer is used. The coupling agent may be diluted with an inert solvent and continuously supplied to the reactor. When the polymerization step is a batch type, the reaction step may be carried out by charging the coupling agent into the polymerization reactor or by transferring the coupling agent to another reactor.

A in the formula (VI) is preferably represented by any of the following general formulas (II) to (V).

In formula (II), B ¹ represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, and a represents an integer of 1 to 10. When there are a plurality of B ¹ , they are independent of each other.

In formula (III), B ² represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, B ³ represents an alkyl group having 1 to 20 carbon atoms, and a represents an integer of 1 to 10 carbon atoms. .. When there are a plurality of B ² and B ³ , they are independent of each other.

In formula (IV), B ⁴ represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, and a represents an integer of 1 to 10. When there are a plurality of B ⁴ , they are independent of each other.

In formula (V), B ⁵ represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, and a represents an integer of 1 to 10. B ^5, when there are a plurality, they are each independently.

When A in formula (VI) is represented by formula (II), the coupling agent is not limited to the following, but for example, tris (3-trimethoxysilylpropyl) amine and bis (3-trimethoxy). Cyrilpropyl)-[3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl] amine, bis [3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl ]-(3-Trimethoxysilylpropyl) amine, tris [3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl] amine, tris (3-ethoxysilylpropyl) amine, bis (3) -Triethoxysilylpropyl)-[3- (2,2-diethoxy-1-aza-2-silacyclopentane) propyl] amine, bis [3- (2,2-diethoxy-1-aza-2-silacyclo) Pentan) propyl]-(3-triethoxysilylpropyl) amine, tris [3- (2,2-diethoxy-1-aza-2-silacyclopentane) propyl] amine, tetrakis (3-trimethoxysilylpropyl)- 1,3-Propanediamine, tris (3-trimethoxysilylpropyl)-[3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl] -1,3-propanediamine, bis (3) -Trimethoxysilylpropyl) -bis [3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl] -1,3-propanediamine, tris [3- (2,2-dimethoxy-1) -Aza-2-silacyclopentane) propyl]-(3-trimethoxysilylpropyl) -1,3-propanediamine, tetrakis [3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl ] -1,3-Propanediamine, tris (3-trimethoxysilylpropyl)-[3- (1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl] -1,3-propanediamine , Bis (3-trimethoxysilylpropyl)-[3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl]-[3- (1-methoxy-2-trimethylsilyl-1-sila-) 2-Azacyclopentane) propyl] -1,3-propanediamine, bis [3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl]-(3-trimethoxysilylpropyl)-[ 3- (1-Methoxy-2-trimethyl Cyril-1-sila-2-azacyclopentane) propyl] -1,3-propanediamine, tris [3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl]-[3-( 1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl] -1,3-propanediamine, tetrakis (3-triethoxysilylpropyl) -1,3-propanediamine, tris (3-tri) Ethoxysilylpropyl)-[3- (2,2-diethoxy-1-aza-2-silacyclopentane) propyl] -1,3-propanediamine, bis (3-triethoxysilylpropyl) -bis [3- ( 2,2-diethoxy-1-aza-2-silacyclopentane) propyl] -1,3-propanediamine, tris [3- (2,2-diethoxy-1-aza-2-silacyclopentane) propyl]- (3-Triethoxysilylpropyl) -1,3-propanediamine, tetrakis [3- (2,2-diethoxy-1-aza-2-silacyclopentane) propyl] -1,3-propanediamine, tris (3) -Triethoxysilylpropyl)-[3- (1-ethoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl] -1,3-propanediamine, bis (3-triethoxysilylpropyl)-[ 3- (2,2-diethoxy-1-aza-2-silacyclopentane) propyl]-[3- (1-ethoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl] -1,3 -Propyldiamine, bis [3- (2,2-diethoxy-1-aza-2-silacyclopentane) propyl]-(3-triethoxysilylpropyl)-[3- (1-ethoxy-2-trimethylsilyl-1) -Sila-2-azacyclopentane) propyl] -1,3-propanediamine, tris [3- (2,2-diethoxy-1-aza-2-silacyclopentane) propyl]-[3- (1-ethoxy) -2-trimethylsilyl-1-sila-2-azacyclopentane) propyl] -1,3-propanediamine, tetrakis (3-trimethoxysilylpropyl) -1,3-bisaminomethylcyclohexane, tris (3-trimethoxy) Cyrilpropyl)-[3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl] -1,3-bisaminomethylcyclohexane, bis (3-trimethoxysilylpropyl) -bis [3- (2,2 -Dimethoxy-1-aza-2-silacyclopentane) propyl] -1,3-bisaminomethylcyclohexane, tris [3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl]-( 3-Trimethoxysilylpropyl) -1,3-bisaminomethylcyclohexane, tetrakis [3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl] -1,3-propanediamine, tris ( 3-Trimethoxysilylpropyl)-[3- (1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl] -1,3-bisaminomethylcyclohexane, bis (3-trimethoxysilylpropyl) )-[3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl]-[3- (1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl]- 1,3-bisaminomethylcyclohexane, bis [3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl]-(3-trimethoxysilylpropyl)-[3- (1-methoxy-) 2-trimethylsilyl-1-sila-2-azacyclopentane) propyl] -1,3-bisaminomethylcyclohexane, tris [3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl]- [3- (1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl] -1,3-bisaminomethylcyclohexane, tetrakis (3-triethoxysilylpropyl) -1,3-propanediamine , Tris (3-triethoxysilylpropyl)-[3- (2,2-diethoxy-1-aza-2-silacyclopentane) propyl] -1,3-bisaminomethylcyclohexane, bis (3-triethoxysilyl) Propyl) -bis [3- (2,2-diethoxy-1-aza-2-silacyclopentane) propyl] -1,3-bisaminomethylcyclohexane, tris [3- (2,2-diethoxy-1-aza) -2-Silacyclopentane) propyl]-(3-triethoxysilylpropyl) -1,3-propanediamine, tetrakis [3- (2,2-diethoxy-1-aza-2-silacyclopentane) propyl]- 1,3-Propyldiamine, Tris (3-triethoxysilylpropyl)-[3- (1-ethoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propi Le] -1,3-bisaminomethylcyclohexane, bis (3-triethoxysilylpropyl)-[3- (2,2-diethoxy-1-aza-2-silacyclopentane) propyl]-[3- (1) -Ethoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl] -1,3-bisaminomethylcyclohexane, bis [3- (2,2-diethoxy-1-aza-2-silacyclopentane) Propyl]-(3-Triethoxysilylpropyl)-[3- (1-ethoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl] -1,3-bisaminomethylcyclohexane, tris [3- (2,2-diethoxy-1-aza-2-silacyclopentane) propyl]-[3- (1-ethoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl] -1,3-bis Examples thereof include aminomethylcyclohexane, tetrax (3-trimethoxysilylpropyl) -1,6-hexamethylenediamine, and pentax (3-trimethoxysilylpropyl) -diethylenetriamine.

When A in formula (VI) is represented by formula (III), the coupling agent is not limited to the following, but for example, tris (3-trimethoxysilylpropyl) -methyl-1,3-propane. Diamine, bis (2-trimethoxysilylpropyl)-[3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl] -methyl-1,3-propanediamine, bis [3- (2) , 2-Dimethoxy-1-aza-2-silacyclopentane) propyl]-(3-trimethoxysilylpropyl) -methyl-1,3-propanediamine, tris (3-triethoxysilylpropyl) -methyl-1, 3-Propyldiamine, bis (2-triethoxysilylpropyl)-[3- (2,2-diethoxy-1-aza-2-silacyclopentane) propyl] -methyl-1,3-propanediamine, bis [3 -(2,2-diethoxy-1-aza-2-silacyclopentane) propyl]-(3-triethoxysilylpropyl) -methyl-1,3-propanediamine, N ¹ , N ¹ '-(propane-1) , 3-Diyl) bis (N ¹ -methyl-N ³ , N ³ -bis (3- (trimethoxysilyl) propyl) -1,3-propanediamine), and N ^1- (3- (bis (3-) bis (3-) (trimethoxysilyl) propyl) amino) propyl) -N ¹ - methyl -N ³ - (3- (methyl (3- (trimethoxysilyl) propyl) amino) propyl) -N ³ - (3- (trimethoxysilyl ) Propyl) -1,3-propanediamine.

When A in formula (VI) is represented by formula (IV), the coupling agent is not limited to the following, but for example, tetrakis [3- (2,2-dimethoxy-1-aza-2-). Silacyclopentane) propyl] silane, tris [3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl]-(3-trimethoxysilylpropyl) silane, tris [3- (2,2) -Dimethoxy-1-aza-2-silacyclopentane) propyl]-[3- (1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl] silane, bis (3-trimethoxysilylpropyl) )-Bis [3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl] silane, (3-trimethoxysilyl)-[3- (1-methoxy-2-trimethylsilyl-1-sila) -2-azacyclopentane) -bis [3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl] silane, bis [3- (1-methoxy-2-trimethylsilyl-1-sila-) 2-Azacyclopentane) -bis [3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl] silane, tris (3-trimethoxysilylpropyl)-[3- (2,2-) Dimethoxy-1-aza-2-silacyclopentane) propyl] silane, bis (3-trimethoxysilylpropyl)-[3- (1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl] -[3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl] silane, bis [3- (1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl] -Bis (3-trimethoxysilylpropyl) silane and bis (3-trimethoxysilylpropyl) -bis [3- (1-methoxy-2-methyl-1-sila-2-azacyclopentane) propyl] silane Can be mentioned.
When A is represented by the formula (IV) in the formula (VI), the coupling agent is not limited to the following, but for example, 3-tris [2- (2,2-dimethoxy-1-aza-). 2-Silacyclopentane) ethoxy] Cyril-1- (2,2-dimethoxy-1-aza-2-silacyclopentane) propane, and 3-tris [2- (2,2-dimethoxy-1-aza-2) -Silacyclopentane) ethoxy] silyl-1-trimethoxysilylpropane.

A coupling agent in which A in the formula (VI) is preferably represented by the formula (II) or the formula (III) and k represents 0 is preferable. Such coupling agents tend to be easily available, and have better grip performance and rolling resistance characteristics on wet road surfaces when the modified conjugated diene polymer composition is used as a vulcanized product. It tends to be. Such coupling agents are not limited to the following, but for example, bis (3-trimethoxysilylpropyl)-[3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl. ] Amin, Tris (3-trimethoxysilylpropyl) amine, Tris (3-triethoxysilylpropyl) amine, Tris (3-trimethoxysilylpropyl)-[3- (2,2-dimethoxy-1-aza-2) -Silacyclopentane) propyl] -1,3-propanediamine, tetrax [3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl] -1,3-propanediamine, tetrakis (3-) Trimethoxysilylpropyl) -1,3-propanediamine, tetrax (3-trimethoxysilylpropyl) -1,3-bisaminomethylcyclohexane, tris (3-trimethoxysilylpropyl) -methyl-1,3-propanediamine , And bis [3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl]-(3-trismethoxysilylpropyl) -methyl-1,3-propanediamine.

A coupling agent in which A in formula (VI) is represented by formula (II) or formula (III), k represents 0, and a in formula (II) or formula (III) represents an integer of 2 to 10. Is more preferable. As a result, the grip performance and rolling resistance characteristics on a wet road surface when the modified conjugated diene polymer composition is vulcanized tend to be more excellent. Such coupling agents are not limited to, but for example, tetrakis [3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl] -1,3-propanediamine. Tetrax (3-trimethoxysilylpropyl) -1,3-propanediamine, tetrakis (3-trimethoxysilylpropyl) -1,3-bisaminomethylcyclohexane, and N ^1- (3- (bis (3- (tri)) trimethoxysilyl) propyl) amino) propyl) -N ¹ - methyl -N ³ - (3- (methyl (3- (trimethoxysilyl) propyl) amino) propyl) -N ³ - (3- (trimethoxysilyl) propyl )-1,3-Propyldiamine.

The amount of the compound represented by the formula (VI) as the coupling agent is adjusted so that the number of moles of the conjugated diene polymer and the number of moles of the coupling agent react at a desired stoichiometric ratio. This tends to achieve the desired degree of branching. The specific number of moles of the polymerization initiator is preferably 5.0 times or more, more preferably 6.0 times or more, based on the number of moles of the coupling agent. In this case, in the formula (VI), the number of functional groups ((m-1) × i + p × j + k) of the coupling agent is preferably an integer of 5 to 10, and more preferably an integer of 6 to 10. ..

The larger the number of functional groups of the compound represented by the formula (VI), the more the degree of branching in the obtained modified conjugated diene polymer is desired when the amount of the coupling agent added cannot be controlled within the desired range in the reaction step. It becomes easy to deviate from the value of. Therefore, it is preferable to appropriately control the amount of the coupling agent added. In order to appropriately control the amount of the coupling agent added, for example, a method of diluting the coupling agent and then adding the coupling agent is preferable. When the deviation of the addition amount is the same, the deviation between the number of moles of the conjugated diene polymer and the number of moles of the coupling agent tends to be smaller when diluted. Further, the water content of the solvent to be diluted is preferably 100 mass ppm or less, more preferably 50 mass ppm or less, still more preferably 30 mass ppm or less, still more preferably 10 mass ppm or less. When the water content of the solvent to be diluted is 100 mass ppm or less, the coupling agent reacts with water and the functional groups in the coupling agent are reduced, so that the molar amount of the conjugated diene polymer is reduced. There is a tendency to suppress the deviation between the number and the number of moles of the coupling agent.

In order for the modified conjugated diene polymer in the present embodiment to have a specific polymer component, the molecular weight distribution (Mw / Mn) of the conjugated diene polymer is preferably 1.5 or more and 2.5 or less. , More preferably 1.8 or more and 2.2 or less. Further, in the obtained modified conjugated diene polymer, it is preferable that a peak is detected in the molecular weight curve by GPC. In this case, the workability and the grip performance on a wet road surface tend to be more excellent.

Modified conjugated Mp ₁ the peak molecular weight by GPC of diene polymer, when the peak molecular weight of the conjugated diene polymer and Mp _2, Mp ₁ and Mp ₂ are preferably the following equation holds.

_{(Mp 1 / Mp 2) <} 1.8 × 10-12 × (Mp 2 -120 × 10 4) 2 + 2

It is more preferable that Mp ₂ is 20 × 10 ⁴ or more and 80 × 10 ⁴ , and Mp ₁ is 30 × 10 ⁴ or more and 150 × 10 ⁴ or less. Mp ₁ and Mp ₂ are determined by the method described in Examples described later.

The ratio of the coupling polymer in the modified conjugated diene polymer in the present embodiment is represented by the modification rate. The modification rate is preferably 30% by mass or more, more preferably 50% by mass or more, and further preferably 70% by mass or more. When the modification rate is 30% by mass or more, the processability of the vulcanized product tends to be excellent, and the grip performance and rolling resistance characteristics of the vulcanized product on a wet road surface tend to be excellent. The ratio of the coupling polymer is synonymous with the modification rate when the coupling residue has a functional group composed of nitrogen and silicon. The denaturation rate is measured by the method described in Examples described later.

In the method for producing a modified diene polymer, a condensation reaction step of carrying out a condensation reaction in the presence of a condensation accelerator may be provided after the reaction step or before the reaction step.

When the conjugated diene portion of the modified conjugated diene polymer is hydrogenated, the method for hydrogenating is not particularly limited, and a known method can be used. As a suitable hydrogenation method, a method of hydrogenating by blowing gaseous hydrogen into the polymer solution in the presence of a catalyst can be mentioned. As the catalyst, for example, a heterogeneous catalyst such as a catalyst in which a noble metal was supported on a porous inorganic substance; a catalyst in which salts such as nickel and cobalt were solubilized and reacted with organic aluminum and the like, and metallocene such as titanosen was used. Examples include homogeneous catalysts such as catalysts. Among these, the titanocene catalyst is preferable from the viewpoint that mild hydrogenation conditions can be selected. Further, hydrogenation of the aromatic group can be carried out by using a supported catalyst of a noble metal.

Specific examples of the hydrogenation catalyst are not limited to the following, but for example, (1) a support type non-uniformity in which a metal such as Ni, Pt, Pd, Ru is supported on carbon, silica, alumina, silica soil or the like. A system hydrogenation catalyst, (2) a so-called Cheegler type hydrogenation catalyst using an organic acid salt such as Ni, Co, Fe, Cr or a transition metal salt such as an acetylacetone salt and a reducing agent such as organic aluminum, (3) Ti. , So-called organometallic complexes such as organometallic compounds such as Ru, Rh, Zr and the like. Further, as hydrogenation catalysts, for example, Japanese Patent Publication No. 42-8704, Japanese Patent Publication No. 43-6636, Japanese Patent Publication No. 63-4841, Japanese Square Root No. 1-377970, Japanese Square Root No. 1-33851 Also mentioned are known hydrogenation catalysts described in JP-A-2-9041 and JP-A-8-109219. Preferred hydrogenation catalysts include reaction mixtures of titanosen compounds and reducing organometallic compounds.

In the method for producing a modified conjugated diene-based polymer, a deactivating agent, a neutralizing agent, or the like may be added to the copolymer solution after the reaction step, if necessary. The inactivating agent is not limited to the following, and examples thereof include water; alcohols such as methanol, ethanol, and isopropanol. The neutralizing agent is not limited to the following, but is, for example, a carboxylic acid such as stearic acid, oleic acid, and versatic acid (a carboxylic acid mixture having 9 to 11 carbon atoms and mainly 10 branches). Acid: An aqueous solution of an inorganic acid, carbon dioxide, and the like.

For the modified conjugated diene polymer, it is preferable to add a stabilizer for rubber from the viewpoint of preventing gel formation after polymerization and improving the stability during processing. The stabilizer for rubber is not limited to the following, and known ones can be used. For example, 2,6-di-tert-butyl-4-hydroxytoluene (BHT), n-octadecyl-3. Antioxidants such as-(4'-hydroxy-3', 5'-di-tert-butylphenol) propinate, 2-methyl-4,6-bis [(octylthio) methyl] phenol are preferred.

In order to further improve the processability of the modified conjugated diene-based polymer, extender oil can be added to the modified conjugated diene-based copolymer, if necessary. The method of adding the spreading oil to the modified conjugated diene-based polymer is not limited to the following, but the spreading oil is added to the polymer solution and mixed to obtain an oil-extended copolymer solution, and the solvent is removed. The method is preferable. Examples of the spreading oil include aroma oil, naphthenic oil, paraffin oil and the like. Among these, an aroma substitute oil having a polycyclic aromatic (PCA) component of 3% by mass or less according to the IP346 method is preferable from the viewpoint of environmental safety, prevention of oil bleeding, and wet grip characteristics. Examples of the aroma substitute oil 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 spreading oil added is not particularly limited, but is preferably 10 parts by mass or more and 60 parts by mass or less, and more preferably 20 parts by mass or more and 37.5 parts by mass or less with respect to 100 parts by mass of the modified conjugated diene polymer.

A known method can be used as a method for obtaining the modified conjugated diene-based polymer from the polymer solution. As the method, for example, after separating the solvent by steam stripping or the like, the polymer is filtered off, and further dehydrated and dried to obtain the polymer, concentrated in a flushing tank, and further bent extruder or the like. Examples include a method of devolatile with a drum dryer and a method of directly devolatile with a drum dryer or the like.

The modified conjugated diene-based polymer composition of the present embodiment may contain a rubber-like component (hereinafter, also referred to as “another rubber-like polymer”) other than the above-mentioned modified conjugated diene-based polymer. The other rubber-like component is not particularly limited, but for example, from the viewpoint of grip performance on a wet road surface, the ratio (Mw / Mn) of the weight average molecular weight Mw to the number average molecular weight Mn by gel permeation chromatography is 1. Other modified rubber-like polymers and / or other non-modified rubber-like polymers (including diene-based polymers and non-diene-based polymers) having a value of .9 or more can be mentioned, from the viewpoint of rolling resistance characteristics. , Other modified rubbery polymers having a ratio (Mw / Mn) of weight average molecular weight Mw to number average molecular weight Mn of 1.9 or more by gel permeation chromatography are preferable.

The other rubber-like polymer is not particularly limited, and for example, at least one rubber-like polymer selected from the modified conjugated diene-based polymer and the natural rubber, high-cis polybutadiene rubber, and polyisoprene rubber described later. Non-polymers, conjugated diene-based polymers or hydrogenated products thereof, random copolymers of conjugated diene-based compounds and vinyl aromatic compounds or hydrogenated products thereof, blocks of conjugated diene-based compounds and vinyl aromatic compounds Examples thereof include a polymer or a hydrogenated product thereof, a non-diene polymer, and the like.

Specific examples of the other rubber-like polymer include styrene-butadiene rubber or a hydrogenated product thereof, a styrene-butadiene block copolymer or a hydrogenated product thereof, a styrene-isoprene block copolymer or a hydrogenated product thereof. Such as styrene-based elastomer, acrylonitrile-butadiene rubber, or a hydrogenated product thereof.
Further, the other rubber-like polymer may be a non-diene polymer, and examples of the non-diene polymer include ethylene-propylene rubber, ethylene-propylene-diene rubber, and ethylene-butene-diene rubber. Olefin-based elastomers such as ethylene-butene rubber, ethylene-hexene rubber, ethylene-octene rubber, butyl rubber, brominated butyl rubber, acrylic rubber, fluororubber, silicone rubber, chlorinated polyethylene rubber, epichlorohydrin rubber, α, β-unsaturated nitrile-acrylic acid Examples thereof include ester-conjugated diene copolymer rubber, urethane rubber, and polysulfide rubber.

The weight average molecular weight Mw of the various rubber-like polymers described above is preferably 2,000 to 2,000,000, preferably 5,000 to 1,500,000 from the viewpoint of the balance between performance and processing characteristics. More preferably.

[Rubber polymer]
The modified conjugated diene polymer composition of the present embodiment preferably further contains 0 to 70 parts by mass of at least one rubber-like polymer selected from natural rubber, high-cis polybutadiene rubber, and polyisoprene rubber. ..
The modified conjugated diene-based polymer composition in the present embodiment is at least one rubber-like polymer selected from natural rubber, high-cis polybutadiene rubber, and polyisoprene rubber, and / or the other rubber-like weight. When a coalescence is included, the total of the modified conjugated diene-based polymer in the present embodiment and these rubber-like polymers is 100 parts by mass.

The natural rubber is a substance containing cis-type polyisoprene contained in the sap of rubber tree as a main component, and is produced by addition polymerization in a living body. It is graded and sorted by visual inspection into the international standard RSS1 to RSS5.
The polyisoprene rubber is a kind of synthetic rubber which is a polyisoprene obtained by chemically polymerizing isoprene. There are some structural differences between polyisoprene rubber and natural rubber polyisoprene. First, with the synthetic polyisoprene contained in the polyisoprene rubber, it is not possible to obtain a 100% cis form at present, and a small amount of trans form is contained. In addition to polyisoprene, natural rubber contains trace amounts of proteins and fatty acids, but synthetic polyisoprene does not have such impurities. Examples of the polyisoprene rubber include JSR IR1220 manufactured by JSR Corporation (trade name).
The high cis polybutadiene rubber is, for example, among polybutadienes produced by solution polymerization using a Ziegler-Natta type coordination catalyst based on titanium, cobalt, and nickel, or in the presence of an alkyllithium compound. Polybutadiene having a high 1,4-cis bond amount, and examples thereof include UBEPOL (registered trademark) BR manufactured by Ube Kosan Co., Ltd.

When the modified conjugated diene-based polymer composition in the present embodiment contains a rubber-like polymer, when the rubber-like polymer is 0 to 70 parts by mass, processing characteristics, running stability, and grip performance on a wet road surface are performed. The sex is further improved. From the viewpoint of the balance between rolling resistance characteristics, processability, running stability, and grip performance on a wet road surface, the blending amounts of the modified conjugated diene polymer composition and the rubber-like polymer are preferably 40 to 60, respectively. It is preferably parts by mass and 60 to 40 parts by mass.

[Silica-based inorganic filler]
The modified conjugated diene polymer composition of the present embodiment contains a silica-based inorganic filler.
From the viewpoint of expressing rolling resistance characteristics, processability, running stability, and grip performance on a wet road surface being practically sufficient, the blending amount of the silica-based inorganic filler is modified in the present embodiment. When the conjugated diene polymer is 100 parts by mass, or contains at least one rubber-like polymer selected from natural rubber, high-cis polybutadiene rubber, and polyisoprene rubber and / or the other rubber-like polymer. The total of the modified conjugated diene polymer and these rubber-like polymers in the present embodiment is 100 parts by mass, which is 20 to 300 parts by mass, preferably 20 to 200 parts by mass, and 20 to 100 parts by mass. Is more preferable.

The silica-based inorganic filler is not particularly limited, but may be a known, solid particles preferably comprise SiO ₂ or Si ₃ Al as a constituent unit, the main structural units of SiO ₂ or Si ₃ Al It is more preferable to use it as an ingredient. Here, "mainly composed" means that the target component is contained in the silica-based inorganic filler in an amount of 50% by mass or more. The silica-based inorganic filler preferably contains SiO ₂ or Si ₃ Al in an amount of 70% by mass or more, more preferably 80% by mass or more.

Specific examples of the silica-based inorganic filler include inorganic fibrous substances such as silica, clay, talc, mica, diatomaceous earth, wollastonite, montmorillonite, zeolite, and glass fiber. Further, a silica-based inorganic filler having a hydrophobic surface or a mixture of a silica-based inorganic filler and a non-silica-based inorganic filler can also be used. Among these, silica and glass fiber are preferable, and silica is more preferable, from the viewpoint of strength, abrasion resistance and the like. Examples of silica include dry silica, wet silica, and synthetic silicate silica. Of these, wet silica is preferred.
Examples of the dry silica include those obtained by reacting purified silicon tetrachloride in a high-temperature flame, having a higher purity than a wet type, fine particles, and extremely low water content. Generally, silicone rubber is used. It is widely used as a filler, a resin thickener, a reinforcing agent, a powder fluidizer, and a raw material for ceramics.
Examples of the wet silica include a light white powder that is fluffy in appearance and is obtained by using sodium silicate made from silica sand as a raw material, neutralizing the aqueous solution to precipitate silica, filtering and drying. Generally used as a reinforcing filler for synthetic rubber, powdering and solidification prevention of liquids such as pesticides, strike-through prevention of printing ink on lightweight paper, paint, thickening / dripping of ink, heat insulating material, and abrasive ..

In the modified conjugated diene polymer composition of the present embodiment, the nitrogen adsorption specific surface area required by the BET adsorption method of the silica-based inorganic filler is 100 to 300 m ² / g from the viewpoint of obtaining better rolling resistance characteristics. It is preferably 170 to 250 m ² / g, and more preferably 170 to 250 m ² / g.

[Tacky Fire (Adhesive Adhesive Resin)]
The modified conjugated diene polymer composition of the present embodiment contains a tack fire. Tacky fire is a tackifier resin.
By containing the tack fire, the processability of the modified conjugated diene polymer composition is improved, and further, the running stability of the tire and the braking performance when the modified conjugated diene polymer composition is used for the tire are improved. It can be improved. The tack fire in the present embodiment is not particularly limited as long as it can be used as a tackifier, but specifically, an aromatic petroleum resin, a kumaron-inden resin, a terpene resin, and a rosin derivative (paulownia oil resin). Includes), tall oils, tall oil derivatives, rosin ester resins, natural and synthetic terpene resins, aliphatic hydrocarbon resins, aromatic hydrocarbon resins, mixed aliphatic-aromatic hydrocarbon resins, coumarin-indene resins, phenols. Resins, p-tert-butylphenol-acetylene resin, phenol-formaldehyde resin, xylene-formaldehyde resin, monoolefin oligomer, diolefin oligomer, aromatic hydrocarbon resin, aromatic petroleum resin, hydride aromatic hydrocarbon resin , Hydrocarbonic hydrocarbon resin, hydrocarbon hydrocarbon resin, hydrocarbon resin, hydride tung oil resin, hydride oil resin, ester of hydride oil resin and monofunctional or polyfunctional alcohol and the like. These resins may be used alone or in combination of two or more. When hydrogenating, all unsaturated groups may be hydrogenated or some may be left.

Among these resins, a resin having a softening point of 50 to 160 ° C. is preferable. Further, among the above resins, a resin (oligomer) having a number average molecular weight of 100 to less than 10,000 is preferable. The number average molecular weight of the tackifier resin can be measured by the same method as the method for measuring the number average molecular weight described in Examples described later. As the tack fire to be used together with the modified conjugated diene-aromatic vinyl copolymer, one having an appropriate aromatic content tends to be compatible with the copolymer, and thus is preferable.
From the viewpoint of grip performance and running stability on wet road surfaces, the amount of tackfire compounded is 100 parts by mass of the modified conjugated diene polymer in the present embodiment, or natural rubber, high cis polybutadiene rubber, and polyisoprene. When at least one rubber-like polymer selected from rubber and / or the other rubber-like polymer is contained, the modified conjugated diene-based polymer in the present embodiment and these rubber-like polymers are combined as a total of 100 parts by mass. , 0.5 parts by mass or more, and preferably 30 parts by mass or less from the viewpoint of rolling resistance. Further, the blending amount of the tack fire is more preferably 1 to 20 parts by mass. Only one type of tack fire may be blended, or two or more kinds may be blended.

[Other ingredients]
The modified conjugated diene polymer composition of the present embodiment is, for example, carbon black, metal oxide, metal hydroxide, in addition to the modified conjugated diene polymer composition, silica-based inorganic filler, and tack fire of the present embodiment. Additives such as substances, silane coupling agents, and rubber softeners can be included.

(Carbon black)
The modified conjugated diene polymer composition of the present embodiment is at least one selected from the modified conjugated diene polymer of the present embodiment in an amount of 100 parts by mass, or natural rubber, high cis polybutadiene rubber, and polyisoprene rubber. When the rubber-like polymer and / or the other rubber-like polymer of the above is contained, the total of the modified conjugated diene-based polymer in the present embodiment and these rubber-like polymers is 100 parts by mass, and the silica-based inorganic filler In addition, it is preferable to further contain 0.5 to 100 parts by mass of carbon black from the viewpoint of reinforcement such as tensile properties.
The carbon black is not particularly limited, and for example, carbon black of each class such as SRF, FEF, HAF, ISAF, and SAF can be used. Among these, carbon black having a nitrogen adsorption specific surface area of 50 m ² / g or more and a dibutyl phthalate (DBP) oil absorption of 80 mL / 100 g or more is preferable from the viewpoint of extrusion moldability and rolling resistance characteristics.
The amount of carbon black blended is 100 parts by mass of the modified conjugated diene polymer in the present embodiment, or natural rubber or high cis polybutadiene, from the viewpoint of the balance between rolling resistance characteristics, extrusion processability, and running stability. When at least one rubber-like polymer selected from rubber and polyisoprene rubber and / or the other rubber-like polymer is contained, the modified conjugated diene-based polymer in the present embodiment and these rubber-like polymers are used. With the total as 100 parts by mass, 0.5 to 100 parts by mass is preferable, 3 to 100 parts by mass is more preferable, and 5 to 50 parts by mass is further preferable.

(Metal oxides and metal hydroxides)
The modified conjugated diene polymer composition of the present embodiment may contain a metal oxide or a metal hydroxide in addition to the silica-based inorganic filler or carbon black. A metal oxide is a solid particle whose main component is the chemical formula M _x O _y (M represents a metal atom, and x and y each independently represent an integer of 1 to 6). For example, alumina, titanium oxide, magnesium oxide, zinc oxide and the like can be mentioned. Further, a mixture of a metal oxide and an inorganic filler other than the metal oxide can also be used. The metal hydroxide is not particularly limited, and examples thereof include aluminum hydroxide, magnesium hydroxide, and zirconium hydride.

(Silane coupling agent)
The modified conjugated diene polymer composition of the present embodiment may contain a silane coupling agent. The silane coupling agent is at least one rubber-like polymer selected from modified diene-based polymers, natural rubbers, high-cis polybutadiene rubbers, and polyisoprene rubbers, other rubber-like polymers, and silica-based inorganic fillers. It has a group of affinity or binding to each of them, and has a function of closely interacting with each other. Generally, a compound having a sulfur bond moiety, an alkoxysilyl group, and a silanol group moiety in one molecule is used.
The silane coupling agent is not limited to, for example, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylethoxysilane, 2-mercaptoethyltrimethoxysilane, 2-mercaptoethyltriethoxysilane, ethoxy. (3-Mercaptopropyl) bis (3,6,9,12,15-pentaoxaoctacosan-1-yloxy) silane [Ebonic Degusa: Si363], Momentive NXT-Z30, NXT-Z45, Silane coupling agents containing mercapto groups such as NXTZ60 and NXTsilane, bis- [3- (triethoxysilyl) -propyl] -tetrasulfide, bis- [3- (triethoxysilyl) -propyl] -disulfide, bis -[2- (Triethoxysilyl) -ethyl] -tetrasulfide, bis (3-triethoxysilylpropyl) trisulfide, bis- [2- (triethoxysilyl) -ethyl] -tetrasulfide, bis (3-tri Methoxysilylpropyl) tetrasulfide, bis (2-trimethoxysilylethyl) tetrasulfide, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 2-mercaptoethyltrimethoxysilane, 2-mercaptoethyltriethoxysilane , 3-Trimethoxysilylpropyl-N, N-dimethylthiocarbamoyltetrasulfide, 3-triethoxysilylpropyl-N, N-dimethylthiocarbamoyltetrasulfide, 2-triethoxysilylethyl-N, N-dimethylthiocarbamoyltetra Sulfide, 3-trimethoxysilylpropyl benzothiazolyl tetrasulfide, 3-triethoxysilylpropyl benzolyl tetrasulfide, 3-triethoxysilylpropyl methacrylate monosulfide, 3-trimethoxysilylpropyl methacrylate monosulfide, bis (3-) Diethoxymethylsilylpropyl) tetrasulfide, 3-mercaptopropyl dimethoxymethylsilane, dimethoxymethylsilylpropyl-N, N-dimethylthiocarbamoyltetrasulfide, dimethoxymethylsilylpropylbenzothiazolyltetrasulfide, and the like. Among them, bis- [3- (triethoxysilyl) -propyl] -disulfide, ethoxy (3-mercaptopropyl) bis (3,6,9,12,15-pentaoxaoctacosane) from the viewpoint of high reinforcing effect. -1-Iloxy) silane [Ebonic Degusa: Si363], Momentive's NXT-Z30, NXT-Z45, NXTZ60, NXTsilane, and other silane coupling agents containing mercapto groups, bis- [3- ( Triethoxysilyl) -propyl] -tetrasulfide is preferred. These silane coupling agents can be used alone or in combination of two or more.

The blending amount of the silane coupling agent is 100 parts by mass of the modified conjugated diene polymer in the present embodiment, or at least one rubber-like polymer selected from natural rubber, high-cis polybutadiene rubber, and polyisoprene rubber. And / or when the other rubber-like polymer is contained, the total of the modified conjugated diene-based polymer in the present embodiment and these rubber-like polymers is 100 parts by mass, preferably 0.1 to 30 parts by mass. 0.5 to 20 parts by mass is more preferable, and 1 to 15 parts by mass is further preferable. When the blending amount of the silane coupling agent is within the above range, the above-mentioned addition effect of the silane coupling agent can be made more remarkable.

(Rubber softener)
The modified conjugated diene polymer composition of the present embodiment may contain a softening agent for rubber in order to improve processability. As the softening agent for rubber, for example, a softening agent for mineral oil-based rubber and a liquid or low molecular weight synthetic softening agent are suitable. Mineral oil-based rubber softeners are also called process oils or extender oils, and are used to soften rubber, increase its volume, and improve processability. The softening agent for mineral oil-based rubber is a mixture of an aromatic ring, a naphthen ring, and a paraffin chain, and the paraffin chain having 50% or more carbon atoms in the total carbon is called paraffin-based, and naphthen is used. Those having a ring carbon number of 30 to 45% are called naphthenic, and those having an aromatic carbon number of more than 30% are called aromatic. As the softening agent for rubber used together with the modified conjugated diene-aromatic vinyl copolymer, one having an appropriate aromatic content tends to have a good affinity with the copolymer, and is preferable.
The amount of the softening agent for rubber is 100 parts by mass of the modified conjugated diene polymer in the present embodiment, or at least one rubber-like polymer selected from natural rubber, high-cis polybutadiene rubber, and polyisoprene rubber. And / or when the other rubber-like polymer is contained, the total of the modified conjugated diene-based polymer in the present embodiment and these rubber-like polymers is 100 parts by mass, preferably 0 to 100 parts by mass, and 10 to 100 parts by mass. 90 parts by mass is more preferable, and 30 to 90 parts by mass is further preferable. If the amount of the softening agent for rubber is too large, bleed-out is likely to occur, and the surface of the composition may become sticky.

[Method for Producing Modified Conjugated Diene Polymer Composition]
In the method for producing a modified conjugated diene-based polymer composition of the present embodiment, a modified conjugated diene-based polymer, a silica-based inorganic filler, a tack fire, and optionally a rubber-like polymer, carbon black or other filler, The method of mixing additives such as a silane coupling agent and a softening agent for rubber is not particularly limited. For example, a melt-kneading method using a general mixer such as an open roll, a Banbury mixer, a kneader, a single-screw screw extruder, a twin-screw screw extruder, or a multi-screw screw extruder. Examples thereof include a method of removing by heating. Of these, a melt-kneading method using a roll, a Banbury mixer, a kneader, or an extruder is preferable from the viewpoint of productivity and good kneading. Further, either a method of kneading the modified conjugated diene polymer and various compounding agents at once or a method of mixing them in a plurality of times can be applied.

The modified conjugated diene-based polymer composition may be a vulcanized rubber composition obtained by subjecting a non-vulcanized modified conjugated diene-based polymer composition to a vulcanization treatment with a vulcanizing agent. As the sulfide agent, for example, a radical generator such as an organic peroxide and an azo compound, an oxime compound, a nitroso compound, a polyamine compound, sulfur, and a sulfur compound can be used. Specific examples of the sulfur compounds include sulfur monochloride, sulfur dichloride, disulfide compounds, and high molecular weight polysulfur compounds. The amount of the vulcanizing agent used is usually 0.01 to 20 parts by mass with respect to 100 parts by mass of the rubber component containing the modified conjugated diene polymer, from 0.1 to 15 parts by mass, from the viewpoint of reinforcing the tensile properties and the like. It is preferably parts by mass. As a vulcanization method, a known method can be applied, and the vulcanization temperature is usually 120 to 200 ° C, preferably 140 to 180 ° C.

Further, in vulcanization, a vulcanization accelerator or a vulcanization aid may be used if necessary. As the vulcanization accelerator, known materials can be used, for example, sulfenamide type, guanidine type, thiuram type, aldehyde-amine type, aldehyde-ammonia type, thiazole type, thiourea type, dithiocarbamate type and the like. The vulcanization accelerator of. As the vulcanization aid, for example, zinc oxide, stearic acid and the like can be used. The amount of the vulcanization accelerator used is usually 0.01 to 20 parts by mass, preferably 0.1 to 15 parts by mass, based on 100 parts by mass of the total of the modified diene polymer and the rubbery polymer. .. The amount of the vulcanization aid used is 0.01 to 20 parts by mass, preferably 0.1 to 15 parts by mass, based on 100 parts by mass of the rubber component.

The modified conjugated diene polymer composition of the present embodiment contains other softeners and fillers other than those described above, as well as heat-resistant stabilizers, antistatic agents, and weather resistance, as long as the object of the present embodiment is not impaired. Various additives such as stabilizers, antistatic agents, colorants, lubricants and the like may be used. As the other softener, a known softener can be used. Specific examples of other fillers include calcium carbonate, magnesium carbonate, aluminum sulfate, barium sulfate and the like. Known materials can be used as the heat-resistant stabilizer, antistatic agent, weather-resistant stabilizer, anti-aging agent, colorant, and lubricant.

A tire can be produced by a usual method using the modified conjugated diene polymer composition of the present embodiment. For example, the modified conjugated diene polymer composition of the present embodiment may be a rubber composition for tire tread. That is, a tire can be manufactured by producing, for example, a tread or the like using the modified conjugated diene-based polymer composition, laminating it together with other members, and heating and pressurizing it using a tire molding machine. The modified conjugated diene-based polymer composition of the present embodiment is preferably a crosslinked product, and a tire containing such a crosslinked product is preferable. By using the modified conjugated diene polymer composition of the present embodiment in a tire, it is possible to manufacture a tire having an excellent balance of rolling resistance characteristics, extrusion processability, and running stability, and particularly excellent rolling resistance characteristics. ..

The present embodiment will be described in more detail with reference to the following examples and comparative examples, but the present invention is not limited to the following examples. The physical properties and evaluation of the modified conjugated diene polymer of the sample were analyzed by the method shown below.

(Physical Properties 1) Amount of Bonded Styrene Using a modified conjugated diene polymer as a sample, 100 mg of the sample was made up to 100 mL with chloroform and dissolved to prepare a measurement sample. Using a spectrophotometer "UV-2450" manufactured by Shimadzu Corporation, the amount of UV absorption wavelength (around 254 nm) absorbed by the phenyl group of styrene is used to bond to 100% by mass of the modified conjugated diene polymer as a sample. The amount of styrene (% by mass) was measured.

(Physical properties 2) Microstructure of butadiene part (1,2-vinyl bond amount)
Using the 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 with a Fourier transform infrared spectrophotometer "FT-IR230" manufactured by JASCO Corporation, and the Hampton method (RR) is based on the absorbance at a predetermined wave number. The microstructure of the butadiene moiety, that is, the amount of 1,2-vinyl bond (mol%) was determined according to the calculation formula of Hampton, Analytical Chemistry 21, 923 (1949).

(Physical Properties 3) Molecular Weight Measurement Condition 1: A GPC measuring device in which three columns using a conjugated diene polymer or a modified conjugated diene polymer as a filler and a polystyrene gel as a filler are connected (trade name "Toso Co., Ltd." HLC-8320GPC ”) was used to measure the chromatogram using an RI detector (trade name“ HLC8020 ”manufactured by Toso), and the weight average molecular weight was measured based on the calibration line obtained using standard polystyrene. (Mw), number average molecular weight (Mn), molecular weight distribution (Mw / Mn), peak top molecular weight of modified conjugated diene polymer (Mp ₁ ), peak top molecular weight of conjugated diene polymer (Mp ₂ ) and their The ratio (Mp ₁ / Mp ₂ ) and the ratio having a molecular weight of 200 × 10 ⁴ or more and 500 × 10 ⁴ or less were determined. The eluent used was THF (tetrahydrofuran) containing 5 mmol / L triethylamine. As the column, three Tosoh product names "TSKgel SuperMultipore HZ-H" were connected, and a Tosoh product name "TSKguardcolum SuperMP (HZ) -H" was connected and used as a guard column in front of the column. 10 mg of the sample for measurement was dissolved in 10 mL of THF to prepare a measurement solution, and 10 μL of the measurement solution was injected into a GPC measuring device and measured under the conditions of an oven temperature of 40 ° C. and a THF flow rate of 0.35 mL / min. Among the various samples measured under the above measurement condition 1, the sample having a molecular weight distribution (Mw / Mn) value of less than 1.6 was measured again under the following measurement condition 2. Tables 1 and 2 show the results of the measurement under the measurement condition 1 for the samples measured under the measurement condition 1 and whose molecular weight distribution value was 1.6 or more.

Measurement condition 2: Using a conjugated diene polymer or a modified conjugated diene polymer as a sample, a chromatogram is measured using a GPC measuring device in which three columns using a polystyrene gel as a filler are connected, and standard polystyrene is measured. Weight average molecular weight (Mw) and number average molecular weight (Mn), peak top molecular weight of modified conjugated diene polymer (Mp ₁ ) and peak top molecular weight of conjugated diene polymer (Mp ₂ ) based on the calibration line using And its ratio (Mp ₁ / Mp ₂ ) and a ratio having a molecular weight of 200 × 10 ⁴ or more and 500 × 10 ⁴ or less. The eluent used was THF containing 5 mmol / L triethylamine. As the column, a guard column: a trade name "TSKguardcolumn SuperH-H" manufactured by Tosoh Corporation, and a column: a trade name "TSKgel SuperH5000", "TSKgel SuperH6000", and "TSKgel SuperH7000" manufactured by Tosoh Co., Ltd. were used. An RI detector (trade name "HLC8020" manufactured by Tosoh Corporation) was used under the conditions of an oven temperature of 40 ° C. and a THF flow rate of 0.6 mL / min. 10 mg of the sample for measurement was dissolved in 20 mL of THF to prepare a measurement solution, and 20 μL of the measurement solution was injected into a GPC measuring device for measurement. Tables 1 and 2 show the results of the measurement under the measurement condition 2 for the sample measured under the measurement condition 1 and the value of the molecular weight distribution was less than 1.6.

The above peak top molecular weights (Mp ₁ and Mp ₂ ) were determined as follows under both measurement conditions 1 and 2. In the GPC curve obtained by measurement, the peak detected as the component having the highest molecular weight was selected. For the selected peak, the molecular weight corresponding to the maximum value of the peak was calculated and used as the peak top molecular weight. In addition, the above ratio of molecular weight 200 × 10 ⁴ or more and 500 × 10 ⁴ or less is 200 × 10 molecular weight from the ratio of the molecular weight 500 × 10 ⁴ or less to the whole from the integrated molecular weight distribution curve under both measurement conditions 1 and 2. Calculated by subtracting the proportion of less than ⁴ .

(Physical properties 4) Contraction factor (g')
A light scattering detector using a GPC measuring device (trade name "GPCmax VE-2001" manufactured by Malvern) in which three columns using a polystyrene gel as a filler are connected using a modified conjugated diene polymer as a sample. , RI detector, and viscosity detector (trade name "TDA305" manufactured by Polymer Co., Ltd.), and three detectors connected in this order were used. Based on standard polystyrene, the absolute molecular weight was determined from the results of the light scattering detector and RI detector, and the intrinsic viscosity was determined from the results of the RI detector and viscosity detector. The linear polymer was used according to the intrinsic viscosity [η] = -3.883M ^0.771, and the shrinkage factor (g') as the ratio of the intrinsic viscosity corresponding to each molecular weight was calculated. The eluent used was 5 mmol / L triethylamine-containing THF. The column was used by connecting the trade names "TSKgel G4000HXL", "TSKgel G5000HXL", and "TSKgel G6000HXL" manufactured by Tosoh Corporation. 20 mg of the sample for measurement was dissolved in 10 mL of THF to prepare a measurement solution, and 100 μL of the measurement solution was injected into a GPC measuring device to measure under the conditions of an oven temperature of 40 ° C. and a THF flow rate of 1 mL / min.

(Physical Properties 5) Polymer Mooney Viscosity Using a conjugated diene-based polymer or a modified conjugated diene-based polymer as a sample, using a Mooney viscometer (trade name "VR1132" manufactured by Ueshima Seisakusho Co., Ltd.), conforming to JIS K6300, L-shaped Mooney viscosity was measured using a rotor. The measurement temperature was 110 ° C. when the conjugated diene polymer was used as a sample, and 100 ° C. when the modified conjugated diene polymer was used as a sample. First, the sample was preheated at the test temperature for 1 minute, the rotor was rotated at 2 rpm, and the torque after 4 minutes was measured to obtain the Mooney viscosity (ML _{(1 + 4)} ).

(Physical properties 6) Glass transition temperature (Tg)
Using a modified conjugated diene polymer as a sample, using a differential scanning calorimeter "DSC3200S" manufactured by MacScience Co., Ltd. in accordance with ISO 22768: 2006, under a flow of helium 50 mL / min, -100 ° C to 20 ° C / min. The DSC curve was recorded while raising the temperature in, and the peak top (Inflection point) of the DSC differential curve was defined as the glass transition temperature.

(Physical properties 7) Modification rate The modification rate was measured by applying the property of adsorbing the modified basic polymer component to a GPC column using a modified conjugated diene polymer as a sample and using a silica gel as a filler. .. Specifically, the sample solution containing the sample and the low molecular weight internal standard polystyrene is adsorbed on the silica-based column based on the difference in the adsorption amount between the chromatogram measured on the polystyrene-based column and the chromatogram measured on the silica-based column. The amount was measured and the modification rate was determined.
Further, for the sample measured under the measurement condition 1 of the above (physical property 3) and the value of the molecular weight distribution under the measurement condition 1 is 1.6 or more, the molecular weight under the following measurement condition 3 and measurement condition 1 For the sample whose distribution value was less than 1.6, the measurement was performed under the following measurement condition 4. The preparation of the sample solution, the measurement condition 3, the measurement condition 4, the GPC measurement condition using the silica-based column, and the calculation method of the denaturation rate are specifically as shown below.
The denaturation rates are shown in Tables 1 and 2.

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

GPC measurement condition using polystyrene column (measurement condition 3): Using the trade name "HLC-8320GPC" manufactured by Tosoh Corporation, 5 mmol / L THF containing triethylamine was used as an eluent, and 10 μL of the sample solution was used as an apparatus. The mixture was injected, and a chromatogram was obtained using an RI detector under the conditions of a column oven temperature of 40 ° C. and a THF flow rate of 0.35 mL / min. As the column, three Tosoh product names "TSKgel SuperMultipore HZ-H" were connected, and a Tosoh product name "TSKguardcolum SuperMP (HZ) -H" was connected and used as a guard column in front of the column.

Measurement conditions 4: 5 mmol / L THF containing triethylamine was used as an eluent, and 20 μL of the sample solution was injected into the apparatus for measurement. As the column, a guard column: a trade name "TSKguardcolumn SuperH-H" manufactured by Tosoh Corporation, and a column: a trade name "TSKgel SuperH5000", "TSKgel SuperH6000", and "TSKgel SuperH7000" manufactured by Tosoh Co., Ltd. were used. Chromatograms were obtained by measurement using an RI detector (HLC8020 manufactured by Tosoh Corporation) under the conditions of a column oven temperature of 40 ° C. and a THF flow rate of 0.6 mL / min.

GPC measurement conditions using a silica-based column: Using the trade name "HLC-8320 GPC" manufactured by Tosoh Corporation, using THF as an eluent, injecting 50 μL of the sample solution into the apparatus, column oven temperature 40 ° C., THF flow rate. Chromatograms were obtained using an RI detector under the condition of 0.5 ml / min. The column is used by connecting the product names "Zorbox PSM-1000S", "PSM-300S", and "PSM-60S", and the product name "DIOL 4.6 x 12.5 mm 5 micron" is used as a guard column in front of the column. Used by connecting.

Calculation method of modification rate: The peak area of the sample is P1, the peak area of standard polystyrene is P2, and the peak area of the chromatogram using the silica column is 100, assuming that the total peak area of the chromatogram using the polystyrene column is 100. The modification rate (%) was calculated from the following formula, assuming that the whole was 100, the peak area of the sample was P3, and the peak area of the standard polystyrene was P4.

Degeneration rate (%) = [1- (P2 × P3) / (P1 × P4)] × 100
(However, P1 + P2 = P3 + P4 = 100)

(Physical property 8) Presence or absence of nitrogen atom The same measurement as in (Physical property 7) was performed, and when the calculated denaturation rate was 10% or more, it was determined to have a nitrogen atom. From this, it was confirmed that the modified conjugated diene-based polymer of Production Examples 1 to 3 had a nitrogen atom and that the modified conjugated diene-based polymer of Production Examples 4 did not have a nitrogen atom.

(Physical properties 9) Presence or absence of silicon atom Using 0.5 g of modified conjugated diene polymer as a sample, an ultraviolet visible spectrophotometer (trade name "UV-" manufactured by Shimadzu Corporation) in accordance with JIS K 0101 44.3.1. It was measured using 1800 ") and quantified by the molybdenum absorptiometry. As a result, when a silicon atom was detected (detection lower limit of 10 mass ppm), it was determined to have a silicon atom. From this, it was confirmed that the modified conjugated diene-based polymer of Production Examples 1 to 4 had a silicon atom.

(Evaluation 1) Formulation Mooney Viscosity Using the formulation obtained above after the second stage kneading and before the third stage kneading as a sample, using a Mooney viscometer, in accordance with JIS K6300-1 After preheating at 100 ° C. for 1 minute, the viscosity after rotating the rotor at 2 rpm for 4 minutes was measured. The result of Comparative Example 1 was indexed as 100. The smaller the index, the better the workability.

(Evaluation 2) Rolling resistance characteristics Using a vulcanized rubber composition sheet as a measurement sample, the viscoelasticity parameters were measured in the torsion mode using a viscoelasticity tester (ARES G-2) manufactured by TA Instrument. Each measured value was indexed with Comparative Example 1 as 100. Tan δ measured at a frequency of 10 Hz and a strain of 3% at 50 ° C. was used as an index of rolling resistance characteristics (fuel efficiency). The smaller the value, the better the rolling resistance characteristics.

(Evaluation 3) Running stability Using a vulcanized rubber composition sheet as a measurement sample, a viscoelasticity parameter was measured in a torsion mode using a viscoelasticity tester (ARES G-2) manufactured by TA Instrument. Each measured value was indexed with Comparative Example 1 as 100. G'measured at a frequency of 10 Hz and a strain of 3% at 50 ° C. was used as an index of stability performance in running (running stability performance). The higher the value, the better the running stability.

(Evaluation 4) Grip performance on wet road surface Using a vulcanized rubber composition sheet as a measurement sample, using a viscoelasticity tester (ARES G-2) manufactured by TA Instrument Co., Ltd., set the viscoelasticity parameters in torsion mode. It was measured. Each measured value was indexed with Comparative Example 1 as 100. Tan δ measured at 0 ° C. at a frequency of 10 Hz and a strain of 1% was used as an index of grip performance (brake performance) on a wet road surface. The higher the value, the better the grip performance on a wet road surface.

[Manufacturing Example 1]
The internal volume is 10 L, the ratio (L / D) of the internal height (L) to the diameter (D) is 4.0, the reactor has an inlet at the bottom and an outlet at the top, and a tank reactor with a stirrer. A tank-type pressure vessel having a stirrer and a jacket for temperature control was used as a polymerization reactor. Preliminarily water-removed 1,3-butadiene was mixed at 17.9 g / min, styrene at 9.8 g / min, and n-hexane at 145.3 g / min. In a static mixer provided in the middle of the pipe for supplying this mixed solution to the inlet of the reactive group, n-butyllithium for the residual impurity inert treatment was added at 0.104 mmol / min, mixed, and then added to the bottom of the reactive group. Supplied continuously. Further, polymerization in which 2,2-bis (2-oxolanyl) propane as a polar substance is vigorously mixed with a stirrer at a rate of 0.0194 g / min and n-butyllithium as a polymerization initiator at a rate of 0.255 mmol / min. It was supplied to the bottom of the reactor and the polymerization reaction was continued continuously. The temperature was controlled so that the temperature of the polymerization solution at the outlet of the top of the reactor was 75 ° C. When the polymerization is sufficiently stable, a small amount of the polymer solution before the addition of the coupling agent is withdrawn from the outlet at the top of the reactor, and the antioxidant (BHT) is added so as to be 0.2 g per 100 g of the polymer, and then the solvent is added. After removal, the Mooney viscosity at 110 ° C. and various molecular weights were measured. Other physical properties are also shown in Table 1.

Next, bis (3-trimethoxysilylpropyl)-[3- (2,2-dimethoxy-1-aza) diluted to 2.74 mmol / L as a coupling agent was added to the polymer solution flowing out from the outlet of the reactor. -2-Silacyclopentane) Propylamine] amine (abbreviated as "A" in the table) was continuously added at a rate of 0.0425 mmol / min (n-hexane solution containing 5.2 ppm of water), and a coupling agent was added. The polymer solution to which was added was mixed by passing through a static mixer and reacted by coupling. At this time, the time until the coupling agent was added to the polymerization solution flowing out from the outlet of the reactor was 4.8 minutes, and the temperature was 68 ° C., and the temperature in the polymerization step and the temperature until the modifier was added. The difference from was 7 ° C. Antioxidant (BHT) was continuously added to the coupling-reacted polymer solution at 0.055 g / min (n-hexane solution) so as to be 0.2 g per 100 g of the polymer, and the coupling reaction was completed. did. At the same time as the antioxidant, oil (JOMO Process NC140 manufactured by JX Nippon Oil & Energy Co., Ltd.) was continuously added to 100 g of the polymer so as to be 37.5 g, and mixed with a static mixer. The solvent was removed by steam stripping to obtain a modified conjugated diene polymer (modified SBR-A). The physical properties of the modified SBR-A are shown in Table 1.

[Manufacturing Example 2]
The amount of treated n-butyllithium added was 0.117 mmol / min, the amount of polymerized n-butyllithium added was 0.242 mmol / min, and the polar substance 2,2-bis (2-oxolanyl) propane was 0.0194 g / min. Then, the coupling agent was changed from bis (3-trimethoxysilylpropyl)-[3- (2,2-dimethoxy-1-aza-2-silacyclopentane) propyl] amine to tetrakis (3-trimethoxysilylpropyl)-. Modified conjugated diene-based weight in the same manner as in Production Example 1 except that the amount of the coupling agent added was 0.0302 mmol / min instead of 1,3-propanediamine (abbreviated as "B" in the table). A coalescence (modified SBR-B) was obtained. Table 1 shows the physical properties of the modified SBR-B.

[Manufacturing Example 3]
The amount of treated n-butyllithium added was 0.114 mmol / min, the amount of polymerized n-butyllithium added was 0.248 mmol / min, and the coupling agent was bis (3-trimethoxysilylpropyl)-[3- (2). , 2-Dimethoxy-1-aza-2-silacyclopentane) propyl] amine is replaced with bis (trimethoxysilyl) ethane (abbreviated as "C" in the table), and the amount of coupling agent added is 0.0620 mmol. A modified conjugated diene polymer (modified SBR-C) was obtained in the same manner as in Production Example 1 except that the ratio was set to / min. Table 1 shows the physical properties of the modified SBR-C.

[Manufacturing Example 4]
The amount of treated n-butyllithium added was 0.114 mmol / min, the amount of polymerized n-butyllithium added was 0.248 mmol / min, and the coupling agent was bis (3-trimethoxysilylpropyl)-[3- (2). , 2-Dimethoxy-1-aza-2-silacyclopentane) propyl] amine was replaced with silicon tetrachloride (abbreviated as "K" in the table), and the amount of coupling agent added was 0.0580 mmol / min. A modified conjugated diene polymer (non-modified SBR) was obtained in the same manner as in Production Example 1 except for the above. Table 1 shows the physical properties of the non-denatured SBR.

[material]
The following materials were used in Examples , Reference Examples and Comparative Examples described later.
-Modified conjugated diene polymer (modified SBR-A)
-Modified conjugated diene polymer (modified SBR-B)
-Modified conjugated diene polymer (modified SBR-C)
-Non-denatured conjugated diene polymer (non-denatured SBR)
-Other rubber-like polymers (modified rubber-like polymer ("Toughden F3440" manufactured by Asahi Kasei Corporation. styrene content 35.5% by mass, vinyl content 40% by mass, weight average molecular weight Mw 1 million, Mw / Mn = 2. Oil (NC140 manufactured by JX Nikko Nisseki Energy Co., Ltd.) added to 100 parts by mass of 19 polymers), 100 ° C. ML viscosity 80)
・ Natural rubber (# RSS3)
・ High Sith Polybutadiene (UBEPOL BR150, manufactured by Ube Industries, Ltd.)
・ Silica (manufactured by Evonik Degussa Japan Co., Ltd., Ultrazil 7000GR, nitrogen adsorption specific surface area: 175 m ² / g)
・ Silane coupling agent (Evonik Degussa Japan Co., Ltd., Si75)
・ Carbon black (manufactured by Tokai Carbon Co., Ltd., Seest KH (N339))
・ Aromatic petroleum resin (manufactured by JX Nippon Oil & Energy Co., Ltd., Nippon Oil Neopolymer 120)
・ Terpene resin (Yasuhara Chemical Co., Ltd., YS resin PX1250)
・ Process oil (manufactured by JX Nippon Oil & Energy Co., Ltd., NC140)
・ Zinc oxide (manufactured by Sakai Chemical Industry Co., Ltd., 2 types of zinc oxide)
・ Stearic acid / wax (manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd., Sanknock)
-Anti-aging agent (N-isopropyl-N'-phenyl-p-phenylenediamine)
-Sulfur / vulcanization accelerator 1 (N-cyclohexyl-2-benzothiazil sulfinamide)
・ Vulcanization accelerator 2 (diphenylguanidine)

[ Reference example 1 ]
According to the formulation shown in Table 2 below, kneading was performed by the following method to obtain an unvulcanized rubber composition and a vulcanized rubber sheet.
First, using a kneader (content capacity 0.5 L) equipped with a temperature control device, the rubber component, silica, and silane coupling agent are used as the first-stage kneading under the conditions of a filling rate of 60% and a rotor rotation speed of 50 rpm. , Aromatic petroleum resin (tack fire) and process oil, process oil containing the process oil contained in the modified SBR-A with respect to 100 parts by mass of the total amount of rubber of the components excluding the oil of the modified SBR-A. The mixture was mixed so that the amount was 42 parts by mass, and kneaded for 4 minutes. At this time, the discharge temperature was adjusted to 155 to 160 ° C. by controlling the temperature of the kneader to obtain a compound.
Next, as the second-stage kneading, the formulation obtained above was cooled to room temperature, carbon black, zinc oxide, stearic acid, wax, and an antiaging agent were added, and the mixture was kneaded with the above kneader for 3 minutes. In this case as well, the discharge temperature was adjusted to 155 to 160 ° C. by controlling the temperature of the kneader.
The discharge temperature was controlled by measuring the temperature of each compound discharged from the kneader after kneading.
Further, after heating the unvulcanized rubber composition at 70 ° C. for 30 minutes using an oven, as a third stage kneading, sulfur and a vulcanization accelerator are added by a 10-inch φ open roll set at 70 ° C. In addition, kneading was performed to obtain an unvulcanized rubber composition. A part was taken out from this unvulcanized rubber composition, and the Mooney viscosity of the unvulcanized rubber composition was measured. Then, the other rest of the unvulcanized rubber composition was vulcanized and molded by a vulcanization press at 160 ° C. for 20 minutes to obtain a vulcanized rubber sheet. The rolling resistance characteristics, running stability, and grip performance on wet road surfaces of the vulcanized rubber sheet were evaluated.

[Example 2]
The unvulcanized rubber composition and the vulcanized rubber sheet were prepared in the same manner as in Reference Example 1 except that the blending amount of the "modified conjugated diene polymer (modified SBR-B)" was 137.5 parts by mass. It was prepared and evaluated for the Mooney viscosity of the formulation, rolling resistance characteristics, running stability, and grip performance on wet road surfaces.

[ Reference example 3 ]
The blending amounts of "modified conjugated diene polymer (modified SBR-A)" and "Hicis polybutadiene (manufactured by Ube Industries, Ltd., UBEPOL BR150)" were adjusted to 96.25 parts by mass and 30 parts by mass, respectively. Except for this, an unvulcanized rubber composition and a vulcanized rubber sheet were prepared in the same manner as in Reference Example 1, and the compound Mooney viscosity, rolling resistance characteristics, running stability, and grip performance on a wet road surface were evaluated. did.

[Example 4]
The blending amounts of "modified conjugated diene polymer (modified SBR-B)" and "HISIS polybutadiene (manufactured by Ube Industries, Ltd., UBEPOL BR150)" were adjusted to 96.25 parts by mass and 30 parts by mass, respectively. Except for this, an unvulcanized rubber composition and a vulcanized rubber sheet were prepared in the same manner as in Reference Example 1, and the compound Mooney viscosity, rolling resistance characteristics, running stability, and grip performance on a wet road surface were evaluated. did.

[ Reference example 5 ]
Except for the fact that the blending amounts of "modified conjugated diene polymer (modified SBR-A)" and "Hicis polybutadiene (manufactured by Ube Industries, Ltd., UBEPOL BR150)" were 44 parts by mass and 60 parts by mass, respectively. Made an unvulcanized rubber composition and a vulcanized rubber sheet in the same manner as in Reference Example 1 , and evaluated the compound Mooney viscosity, rolling resistance characteristics, running stability, and grip performance on a wet road surface.

[Example 6]
Except for the fact that the blending amounts of "modified conjugated diene polymer (modified SBR-B)" and "Hicis polybutadiene (manufactured by Ube Industries, Ltd., UBEPOL BR150)" were 44 parts by mass and 60 parts by mass, respectively. Made an unvulcanized rubber composition and a vulcanized rubber sheet in the same manner as in Reference Example 1 , and evaluated the compound Mooney viscosity, rolling resistance characteristics, running stability, and grip performance on a wet road surface.

[ Reference example 7 ]
"Modified conjugated diene polymer (modified SBR-A)" and other rubber-like polymers such as "modified rubber-like polymer (" Toughden F3440 "manufactured by Asahi Kasei Co., Ltd." and "Hicis Polybutadiene (Ube Kosan Co., Ltd.)" ) Ltd., the amount of UBEPOL BR150) ", 44 parts by weight, respectively, and 11 parts by weight, except that the 30 parts by weight, was used further to" natural rubber (# RSS3) "30 parts by weight, reference example 1 In the same manner, an unvulcanized rubber composition and a vulcanized rubber sheet were prepared, and the Mooney viscosity, rolling resistance characteristics, running stability, and grip performance on a wet road surface were evaluated.

[Example 8]
"Modified conjugated diene polymer (modified SBR-B)" and other rubber-like polymers such as "modified rubber-like polymer (" Toughden F3440 "manufactured by Asahi Kasei Co., Ltd." and "Hicis Polybutadiene (Ube Kosan Co., Ltd.)" ) Ltd., the amount of UBEPOL BR150) ", 44 parts by weight, respectively, and 11 parts by weight, except that the 30 parts by weight, was used further to" natural rubber (# RSS3) "30 parts by weight, reference example 1 In the same manner, an unvulcanized rubber composition and a vulcanized rubber sheet were prepared, and the Mooney viscosity, rolling resistance characteristics, running stability, and grip performance on a wet road surface were evaluated.

[ Reference example 9 ]
Except for using 44 parts by mass and 60 parts by mass of the blending amounts of "modified conjugated diene polymer (modified SBR-A)" and "Hicis polybutadiene (manufactured by Ube Industries, Ltd., UBEPOL BR150)" Made an unvulcanized rubber composition and a vulcanized rubber sheet in the same manner as in Reference Example 1 , and evaluated the compound Mooney viscosity, rolling resistance characteristics, running stability, and grip performance on a wet road surface.

[Comparative Example 1]
Except for the fact that 137.5 parts by mass of the "modified conjugated diene polymer (modified SBR-C)" prepared in Production Example 3 was used instead of the "modified conjugated diene polymer (modified SBR-A)". An unvulcanized rubber composition and a vulcanized rubber sheet were prepared in the same manner as in Reference Example 1, and the compound Mooney viscosity, rolling resistance characteristics, running stability, and grip performance on a wet road surface were evaluated.

[Comparative Example 2]
Reference example except that 137.5 parts by mass of the "non-modified conjugated diene polymer (non-modified SBR)" prepared in Production Example 3 is used instead of the "modified conjugated diene polymer (modified SBR-A)". An unvulcanized rubber composition and a vulcanized rubber sheet were prepared in the same manner as in 1, and the compound Mooney viscosity, rolling resistance characteristics, running stability, and grip performance on a wet road surface were evaluated.

[Comparative Example 3]
An unvulcanized rubber composition and a vulcanized rubber sheet were prepared in the same manner as in Reference Example 1 except that "aromatic petroleum resin (tack fire)" was not blended, and the blended Mooney viscosity and rolling resistance were prepared. The characteristics, running stability, and grip performance on wet roads were evaluated.

Table 2 shows the compounding compositions of Examples 2, 4, 6, 8, Reference Examples 1 , 3 , 5 , 7 , 9 , and Comparative Examples 1, 2, and 3. Table 3 shows the evaluation results of the compound Mooney viscosity, rolling resistance characteristics, running stability, and grip performance on a wet road surface in the same Example, Reference Example , and Comparative Example.

* In the table, Examples 1, 3, 5, 7, and 9 are reference examples.

* In the table, Examples 1, 3, 5, 7, and 9 are reference examples.

[ Reference example 10 ]
According to the formulation shown in Table 4 below, kneading was performed by the following method to obtain an unvulcanized rubber composition and a vulcanized rubber sheet.
First, using a kneader (content capacity 0.5 L) equipped with a temperature control device, the rubber component, silica, and silane coupling agent are used as the first-stage kneading under the conditions of a filling rate of 60% and a rotor rotation speed of 50 rpm. , Terpene resin (tack fire) and process oil, the amount of process oil including the process oil contained in modified SBR-A is 100 parts by mass of the total amount of rubber of the components excluding the oil of modified SBR-A. It was mixed so as to have 42 parts by mass and kneaded for 4 minutes. At this time, the discharge temperature was adjusted to 155 to 160 ° C. by controlling the temperature of the kneader to obtain a compound.
Next, as the second-stage kneading, the formulation obtained above was cooled to room temperature, carbon black, zinc oxide, stearic acid, wax, and an antiaging agent were added, and the mixture was kneaded with the above kneader for 3 minutes. In this case as well, the discharge temperature was adjusted to 155 to 160 ° C. by controlling the temperature of the kneader.
The discharge temperature was controlled by measuring the temperature of each compound discharged from the kneader after kneading.
Further, after heating the unvulcanized rubber composition at 70 ° C. for 30 minutes using an oven, as a third stage kneading, sulfur and a vulcanization accelerator are added by a 10-inch φ open roll set at 70 ° C. In addition, kneading was performed to obtain an unvulcanized rubber composition. A part was taken out from this unvulcanized rubber composition, and the Mooney viscosity of the unvulcanized rubber composition was measured. Then, the other rest of the unvulcanized rubber composition was vulcanized and molded by a vulcanization press at 160 ° C. for 20 minutes to obtain a vulcanized rubber sheet. The rolling resistance characteristics, running stability, and grip performance on wet road surfaces of the vulcanized rubber sheet were evaluated.

[Example 11]
The unvulcanized rubber composition and the vulcanized rubber sheet were prepared in the same manner as in Reference Example 10 except that the blending amount of the "modified conjugated diene polymer (modified SBR-B)" was 137.5 parts by mass. It was prepared and evaluated for the Mooney viscosity of the formulation, rolling resistance characteristics, running stability, and grip performance on wet road surfaces.

[ Reference example 12 ]
The blending amounts of "modified conjugated diene polymer (modified SBR-A)" and "Hicis polybutadiene (manufactured by Ube Industries, Ltd., UBEPOL BR150)" were adjusted to 96.25 parts by mass and 30 parts by mass, respectively. Except for this, an unvulcanized rubber composition and a vulcanized rubber sheet were prepared in the same manner as in Reference Example 10, and the compound Mooney viscosity, rolling resistance characteristics, running stability, and grip performance on a wet road surface were evaluated. did.

[Example 13]
The blending amounts of "modified conjugated diene polymer (modified SBR-B)" and "HISIS polybutadiene (manufactured by Ube Industries, Ltd., UBEPOL BR150)" were adjusted to 96.25 parts by mass and 30 parts by mass, respectively. Except for this, an unvulcanized rubber composition and a vulcanized rubber sheet were prepared in the same manner as in Reference Example 10, and the compound Mooney viscosity, rolling resistance characteristics, running stability, and grip performance on a wet road surface were evaluated. did.

[ Reference example 14 ]
Except for the fact that the blending amounts of "modified conjugated diene polymer (modified SBR-A)" and "Hicis polybutadiene (manufactured by Ube Industries, Ltd., UBEPOL BR150)" were 44 parts by mass and 60 parts by mass, respectively. Made an unvulcanized rubber composition and a vulcanized rubber sheet in the same manner as in Reference Example 10 , and evaluated the compound Mooney viscosity, rolling resistance characteristics, running stability, and grip performance on a wet road surface.

[Example 15]
Except that the blending amounts of "modified conjugated diene polymer (modified SBR-B)" and "Hicis polybutadiene (manufactured by Ube Industries, Ltd., UBEPOL BR150)" were 44 parts by mass and 60 parts by mass, respectively. Made an unvulcanized rubber composition and a vulcanized rubber sheet in the same manner as in Reference Example 10 , and evaluated the compound Mooney viscosity, rolling resistance characteristics, running stability, and grip performance on a wet road surface.

[ Reference example 16 ]
"Modified conjugated diene polymer (modified SBR-A)" and other rubber-like polymers such as "modified rubber-like polymer (" Toughden F3440 "manufactured by Asahi Kasei Co., Ltd." and "Hicis Polybutadiene (Ube Kosan Co., Ltd.)" ) Ltd., the amount of UBEPOL BR150) ", 44 parts by weight, respectively, and 11 parts by weight, except that the 30 parts by weight, was used further to" natural rubber (# RSS3) "30 parts by weight, reference example 10 In the same manner, an unvulcanized rubber composition and a vulcanized rubber sheet were prepared, and the Mooney viscosity, rolling resistance characteristics, running stability, and grip performance on a wet road surface were evaluated.

[Example 17]
"Modified conjugated diene polymer (modified SBR-B)" and other rubber-like polymers such as "modified rubber-like polymer (" Toughden F3440 "manufactured by Asahi Kasei Co., Ltd." and "Hicis Polybutadiene (Ube Kosan Co., Ltd.)" ) Ltd., the amount of UBEPOL BR150) ", 44 parts by weight, respectively, and 11 parts by weight, except that the 30 parts by weight, was used further to" natural rubber (# RSS3) "30 parts by weight, reference example 10 In the same manner, an unvulcanized rubber composition and a vulcanized rubber sheet were prepared, and the Mooney viscosity, rolling resistance characteristics, running stability, and grip performance on a wet road surface were evaluated.

[ Reference example 18 ]
Except for using 44 parts by mass and 60 parts by mass of the blending amounts of "modified conjugated diene polymer (modified SBR-A)" and "HISIS polybutadiene (manufactured by Ube Industries, Ltd., UBEPOL BR150)", respectively. Made an unvulcanized rubber composition and a vulcanized rubber sheet in the same manner as in Reference Example 10 , and evaluated the compound Mooney viscosity, rolling resistance characteristics, running stability, and grip performance on a wet road surface.

[Comparative Example 4]
Except for the fact that 137.5 parts by mass of the "modified conjugated diene polymer (modified SBR-C)" prepared in Production Example 3 was used instead of the "modified conjugated diene polymer (modified SBR-A)". An unvulcanized rubber composition and a vulcanized rubber sheet were prepared in the same manner as in Reference Example 10, and the compound Mooney viscosity, rolling resistance characteristics, running stability, and grip performance on a wet road surface were evaluated.

[Comparative Example 5]
Except for the fact that 137.5 parts by mass of the "non-modified conjugated diene polymer (non-modified SBR)" prepared in Production Example 3 was used instead of the "modified conjugated diene polymer (modified SBR-A)". An unvulcanized rubber composition and a vulcanized rubber sheet were prepared in the same manner as in Reference Example 10, and the compound Mooney viscosity, rolling resistance characteristics, running stability, and grip performance on a wet road surface were evaluated.

[Comparative Example 6]
"Unvulcanized rubber composition and vulcanized rubber sheet were prepared in the same manner as in Reference Example 10 except that the terpene resin (tack fire) was not blended, and the blended Mooney viscosity, rolling resistance characteristics, and running The stability and grip performance on a wet road surface were evaluated.

Table 4 shows the compounding compositions of Examples 11, 13 , 15, 17, Reference Examples 10 , 12 , 14 , 16, 18 and Comparative Examples 4, 5, and 6. Table 5 shows the evaluation results of the compound Mooney viscosity, rolling resistance characteristics, running stability, and grip performance on a wet road surface in the same Example, Reference Example , and Comparative Example.

* In the table, Examples 10, 12, 14, 16 and 18 are reference examples.

* In the table, Examples 10, 12, 14, 16 and 18 are reference examples.

According to the present invention, a rubber composition for a tread having an excellent balance between rolling resistance characteristics, workability, running stability and grip performance on a wet road surface can be obtained, and the rolling resistance characteristics, running stability and running stability can be obtained by using the rubber composition. It is possible to obtain a tire having excellent grip performance on a wet road surface.

Claims (7)

A weight-average molecular weight of 20 × 10 ⁴ or more 300 × 10 ⁴ or less, shrinkage factor (g ') is Ri der less than 0.64, and the degree of branching is modified conjugated diene-based polymer to 100 parts by mass of 7 or more When,
20 to 300 parts by mass of silica-based inorganic filler, and
A modified conjugated diene-based polymer composition containing 0.5 to 30 parts by mass of a tack fire.
The modified conjugated diene polymer, based on the total amount of the modified conjugated diene polymer, molecular weight of 200 × 10 ⁴ or more 500 × 10 ⁴ or less modified conjugated diene-based polymer, 0.25 wt% Including 30% by mass or more,
The modified conjugated diene polymer composition. The modified conjugated diene-based polymer composition according to claim 1, further comprising 0 to 70 parts by mass of at least one rubber-like polymer selected from the group consisting of natural rubber, high-cis polybutadiene rubber, and polyisoprene. The modified conjugated diene polymer, a molecular weight of 200 × 10 ⁴ or more 500 × 10 ⁴ or less modified conjugated diene-based polymer, based on the total amount of the modified conjugated diene polymer, 1.0 wt% The modified conjugated diene-based polymer composition according to claim 1 or 2, which comprises 30% by mass or more. The modified conjugated diene polymer composition according to any one of claims 1 to 3, wherein the modified conjugated diene polymer is represented by the following general formula (I).
(In formula (I), D ¹ represents a diene polymer chain, R ^{1 to} R ³ each independently represent a single bond or an alkylene group having 1 to 20 carbon atoms, and R ⁴ and R ⁷ are. , Each independently indicate an alkyl group having 1 to 20 carbon atoms, and R ⁵ , R ⁸ and R ⁹ independently indicate a hydrogen atom or an alkyl group having 1 to 20 carbon atoms, and R ⁶ and R ^{10 respectively.} Independently represent an alkylene group having 1 to 20 carbon atoms, R ¹¹ represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms, and m and x each independently represent an integer of 1 to 3 carbon atoms. Shown, x ≦ m, p represents 1 or 2, y represents an integer of 1 to 3, y ≦ (p + 1), and z represents an integer of 1 or 2. D ¹ , R ^{1 to} R ¹¹ , m, p, x, y, and z are independent of each other and may be the same or different. I is an integer of 0 to 6. Indicated, j indicates an integer of 0 to 6, k indicates an integer of 0 to 6, (i + j + k) is an integer of 3 to 10, and ((x × i) + (y × j) + (Z × k)) is an integer of 5 to 30. A is a hydrocarbon group having 1 to 20 carbon atoms or a group consisting of an oxygen atom, a nitrogen atom, a silicon atom, a sulfur atom, and a phosphorus atom. Indicates an organic group having at least one selected atom and having no active hydrogen.) The modified conjugated diene-based polymer composition according to claim 4, wherein A in the formula (I) is represented by any of the following general formulas (II) to (V).
(In formula (II), B ¹ represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, a represents an integer of 1 to 10, and B ¹ represents a plurality of B ¹ independently. There.)
(In formula (III), B ² represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, B ³ represents an alkyl group having 1 to 20 carbon atoms, and a represents an integer of 1 to 10 carbon atoms. Shown. If there are multiple B ² and B ³ , they are independent of each other.)
(In formula (IV), B ⁴ represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, a represents an integer of 1 to 10. B ⁴ represents an integer of 1 to 10; and B ⁴ is independent of each other when there are a plurality of them. There.)
(In the formula (V), B ⁵ represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, a represents an integer of 1 to 10. If there are a plurality of B ^{5, they} are independent of each other. There.) The modified conjugated diene-based polymer composition according to any one of claims 1 to 5, which is a rubber composition for a tire tread. A tire containing a crosslinked product of the modified conjugated diene polymer composition according to any one of claims 1 to 6.