CN109384982B

CN109384982B - Modified conjugated diene polymer composition and tire

Info

Publication number: CN109384982B
Application number: CN201810869794.3A
Authority: CN
Inventors: 齐藤齐
Original assignee: Asahi Kasei Corp
Current assignee: Asahi Kasei Corp
Priority date: 2017-08-04
Filing date: 2018-08-02
Publication date: 2020-11-17
Anticipated expiration: 2038-08-02
Also published as: CN109384982A; KR20190015125A; JP2019031659A

Abstract

The present invention relates to a modified conjugated diene polymer composition and a tire, and provides a modified conjugated diene polymer composition having an excellent balance among rolling resistance characteristics, steering stability and wet grip performance. A modified conjugated diene polymer composition comprising a rubber component and an oil (ii), wherein the rubber component contains a modified conjugated diene polymer (i) having a ratio Mw/Mn of a weight average molecular weight Mw to a number average molecular weight Mn, which is obtained by Gel Permeation Chromatography (GPC), of less than 1.5 and having adsorptivity to a silica column, and the oil (ii) has a density of more than 1.0g/cm³。

Description

Modified conjugated diene polymer composition and tire

Technical Field

The present invention relates to a modified conjugated diene polymer composition and a tire.

Background

In recent years, with the emphasis on resource conservation and environmental policy, the level of demand for tires for automobiles having excellent fuel economy has been increasing.

As a method for manufacturing a tire excellent in fuel economy, the following methods are known: the tread is formed into a 2-layer structure of a tread cap on the ground contact surface side and a tread base on the opposite surface side, and as a rubber material constituting the tread, a rubber material capable of forming a crosslinked rubber having excellent rolling resistance characteristics is used in order to reduce rolling resistance and suppress energy loss of the tire.

In view of the strong demand for the fuel economy of a tire, in order to obtain a tire having more excellent fuel economy, a technique for improving the rolling resistance characteristics of a rubber material constituting a tread has been studied.

As a method for improving the rolling resistance characteristics of a rubber material, a method using an inorganic filler such as silica is generally used.

However, it is known that the use of an inorganic filler such as silica lowers the storage modulus, fracture resistance, abrasion resistance, and the like. In order to improve this drawback, compounding of a silane coupling agent is generally carried out, but a sufficient effect has not been obtained yet.

In particular, storage modulus is an important rubber property, and for example, when rubber is used for a tread of a tire, if the storage modulus is insufficient, rigidity is reduced, which leads to a reduction in steering stability. On the other hand, rolling resistance characteristics and steering stability are becoming more and more important with the improvement of automobile performance.

As a technique for improving the balance between rolling resistance characteristics and steering stability of a rubber material containing an inorganic filler, for example, patent document 1 discloses a technique for compounding an additive containing, as active ingredients, a compound having a reactive group with respect to a rubber and an adsorptive group with respect to an inorganic filler in the same molecule, and an aliphatic amine.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2003-183445

Disclosure of Invention

Problems to be solved by the invention

However, in the production of a composition containing the predetermined additive described in patent document 1, it is necessary to add a new predetermined additive to a conventionally used material composition, and there is a problem that the production process is complicated.

In addition, the technique described in patent document 1 has the following problems: although the steering stability of the compound is improved, only the rolling resistance characteristics are maintained, and therefore, when the compound is used as a material for a tread base, sufficient characteristics are not obtained in the balance of the rolling resistance characteristics, steering stability, and wet grip, and further improvement is required.

In view of the above-mentioned problems of the prior art, an object of the present invention is to provide a modified conjugated diene polymer composition having a high balance among rolling resistance characteristics, steering stability and wet grip performance.

Means for solving the problems

The present inventors have conducted intensive studies to solve the above-mentioned problems of the prior art, and as a result, have found that a modified conjugated diene polymer composition containing: a rubber component containing a modified conjugated diene polymer having a predetermined molecular weight distribution); and an oil having a specified density.

Namely, the present invention is as follows.

[1]

A modified conjugated diene polymer composition comprising a rubber component and an oil (ii),

the rubber component contains a modified conjugated diene polymer (i) having a ratio Mw/Mn of a weight average molecular weight Mw to a number average molecular weight Mn, which is obtained by Gel Permeation Chromatography (GPC), of less than 1.5 and having an adsorbability to a silica-based column,

the density of the oil (ii) is more than 1.0g/cm³。

[2]

A modified conjugated diene polymer composition comprising a rubber component, a silica-based inorganic filler and an oil (ii),

the rubber component contains a modified conjugated diene polymer (i) having a ratio Mw/Mn of a weight average molecular weight Mw to a number average molecular weight Mn, which is obtained by Gel Permeation Chromatography (GPC), of less than 1.5 and having an adsorbability to a silica column, wherein the oil (ii) has a density of 1.0g/cm³The above.

[3]

The modified conjugated diene polymer composition according to [1] or [2], wherein the modification ratio of the modified conjugated diene polymer (i) is 60% by mass or more.

[4]

The modified conjugated diene polymer composition according to [1] or [3], wherein the composition further contains a silica-based inorganic filler.

[5]

The modified conjugated diene polymer composition according to any one of the above [1] to [4], which further contains carbon black.

[6]

The modified conjugated diene polymer composition according to any one of the above [1] to [5], wherein the composition is a composition for a base tread.

[7]

A tire comprising a tread base comprising a crosslinked product of the modified conjugated diene polymer composition according to any one of [1] to [6 ].

Effects of the invention

According to the present invention, a modified conjugated diene polymer composition having an excellent balance among rolling resistance characteristics, steering stability, and wet grip performance can be obtained.

Detailed Description

The present embodiment (hereinafter referred to as "the present embodiment") will be described in detail below. The following embodiments are illustrative of the present invention, and are not intended to limit the present invention to the following. The present invention can be implemented by being variously modified within the scope of the gist thereof.

[ modified conjugated diene Polymer composition ]

The modified conjugated diene polymer composition according to embodiment 1 contains a rubber component and has a density of more than 1.0g/cm³The rubber component (ii) contains a modified conjugated diene polymer (i) having a ratio of a weight average molecular weight Mw to a number average molecular weight Mn, Mw/Mn, obtained by Gel Permeation Chromatography (GPC), of less than 1.5, and the rubber component (i) containsThe diene polymer (i) has adsorption to the silica column.

The modified conjugated diene polymer composition of embodiment 2 contains a rubber component, a silica-based inorganic filler and a filler having a density of 1.0g/cm³And (ii) the rubber component contains a modified conjugated diene polymer (i) having an adsorption property to a silica column, wherein the ratio Mw/Mn of the weight average molecular weight Mw to the number average molecular weight Mn, which is obtained by Gel Permeation Chromatography (GPC), is less than 1.5.

(modified conjugated diene Polymer (i))

The rubber component used in the modified conjugated diene polymer composition of the present embodiment contains a modified conjugated diene copolymer (i) having an adsorption property to a silica column, and a ratio Mw/Mn of a weight average molecular weight Mw to a number average molecular weight Mn of less than 1.5 by Gel Permeation Chromatography (GPC).

When the modified conjugated diene polymer (i) has an Mw/Mn of less than 1.5, it is preferable that the modified conjugated diene polymer (i) has a smaller number of free terminal chains than the modified conjugated diene polymer having an Mw/Mn of 1.5 or more, and therefore has better rolling resistance characteristics. The modified conjugated diene polymer (i) preferably has an Mw/Mn of 1.4 or less, more preferably 1.3 or less.

The Mw/Mn of the modified conjugated diene polymer (i) can be controlled within the above numerical range by appropriately adjusting the polymerization conditions of the conjugated diene polymer.

In order to impart the modified conjugated diene polymer (i) with adsorption to the silica-based column, it is effective to adjust the functional group and molecular structure. Examples of the modified conjugated diene polymer (i) having adsorption to a silica column include: a modified conjugated diene polymer having a branched molecular structure with a nitrogen-containing epoxy substituent or a nitrogen-containing alkoxysilane substituent as a branching origin.

It is considered that the interaction between the silica particles blended in the tire and the modified conjugated diene polymer makes the silica particles well dispersed, thereby improving the rolling resistance characteristics of the tire. The present inventors have focused attention on the fact that a modified conjugated diene polymer that interacts with silica particles exhibits a property of adsorbing to silica columns, and set this property as an essential feature of a modified conjugated diene polymer composition having a good balance between rolling resistance characteristics and handling stability.

In the present specification, the "silica-based column" refers to a column packed with a porous silica gel having a diameter of several micrometers to several tens micrometers, and includes an aqueous/organic solvent-based dual-purpose GPC column in addition to an organic solvent-based GPC column used in examples described later.

The term "having adsorbability" as used herein means that the modification ratio obtained by the modification ratio measurement in examples described later satisfies 5% or more.

The modified conjugated diene polymer having a branched molecular structure with a nitrogen-containing epoxy substituent or a nitrogen-containing alkoxysilane substituent as a branching origin is obtained by: the modified conjugated diene polymer is obtained by reacting a compound having a nitrogen atom in the molecule and 2 or more epoxy groups with the polymerization active end of a conjugated diene polymer obtained by polymerizing a conjugated diene compound using, for example, an anionic polymerization initiator or copolymerizing a conjugated diene compound and an aromatic vinyl compound, or reacting a compound having a nitrogen atom in the molecule and 2 or more alkoxy groups bonded to a silyl group with the polymerization active end of a conjugated diene polymer.

The modification ratio of the modified conjugated diene polymer (i) contained in the rubber component used in the modified conjugated diene polymer composition of the present embodiment can be measured by the method described in the examples described later, and is preferably 60% by mass or more, more preferably 80% by mass or more, and further preferably 85% by mass or more, from the viewpoint of improving rolling resistance characteristics and wet grip properties.

The modification ratio of the modified conjugated diene polymer (i) can be controlled within the above numerical range by appropriately controlling the amount of the modifier to the conjugated diene polymer before modification.

The conjugated diene compound used to form the conjugated diene polymer is not particularly limited, and examples thereof include 1, 3-butadiene, isoprene, 2, 3-dimethyl-1, 3-butadiene, 1, 3-pentadiene, 3-methyl-1, 3-pentadiene, 1, 3-heptadiene, and 1, 3-hexadiene. Among these, 1, 3-butadiene and isoprene are preferable from the viewpoint of easy industrial availability. These substances may be used not only in 1 kind but also in 2 or more kinds in combination. 1, 3-butadiene is particularly preferred.

The aromatic vinyl compound is not particularly limited as long as it is a monomer copolymerizable with the conjugated diene compound, and examples thereof include styrene, p-methylstyrene, α -methylstyrene, vinylethylbenzene, vinylxylene, vinylnaphthalene, and diphenylethylene. Among these, styrene is preferred in view of easy industrial availability. These substances may be used not only in 1 kind but also in 2 or more kinds in combination.

The conjugated diene polymer may be a random copolymer or a block copolymer.

Examples of random copolymers include, but are not limited to, the following: such as butadiene-isoprene random copolymer, butadiene-styrene random copolymer, isoprene-styrene random copolymer, butadiene-isoprene-styrene random copolymer, and the like. The composition distribution of the monomers in the copolymer chain includes, but is not limited to, the following: such as completely random copolymers having close to statistically random compositions, tapered (gradient) random copolymers having a tapered composition, and the like. The composition of the bonding pattern (i.e., 1, 4-bonding, 1, 2-bonding, etc.) of the conjugated diene may be uniform or may have a distribution.

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

In the above formulae, the boundaries of the blocks do not necessarily need to be clearly distinguished. For example, in the case where the block B is a copolymer of an aromatic vinyl compound and a conjugated diene compound, the aromatic vinyl compound in the block B may be uniformly distributed or may be distributed in a tapered manner. In the block B, 2 or more of the uniformly distributed portion and/or the tapered portion of the aromatic vinyl compound may coexist. In the block B, 2 or more segments having different aromatic vinyl compound contents may coexist. When the copolymer contains 2 or more blocks S and B, the structures such as the molecular weight and the composition thereof may be the same or different.

The modified conjugated diene polymer in a state after the modification step described later may be a hydrogenated modified conjugated diene polymer in which all or a part of double bonds of the conjugated diene polymer are converted into saturated hydrocarbons after the modification.

In this case, the heat resistance and weather resistance are improved, and the deterioration of the product during processing at high temperature can be prevented. As a result, the composition can exhibit more excellent performance in various applications such as automobile applications.

More specifically, the hydrogenation ratio of the unsaturated double bonds based on the conjugated diene compound (i.e., "hydrogenation ratio") may be arbitrarily selected depending on the purpose, and is not particularly limited. When the rubber composition is used as a vulcanized rubber, it is preferable that a part of the double bonds of the conjugated diene portion remain. From this viewpoint, the hydrogenation ratio of the conjugated diene portion in the polymer is preferably 3 to 70%, more preferably 5 to 65%, and still more preferably 10 to 60%. The hydrogenation rate of the aromatic double bonds based on the aromatic vinyl compound in the copolymer of the conjugated diene compound and the aromatic vinyl compound is not particularly limited, but is preferably 50% or less, more preferably 30% or less, and still more preferably 20% or less. The hydrogenation rate can be determined by a nuclear magnetic resonance apparatus (NMR).

The amount of the bonded conjugated diene in the modified conjugated diene polymer (i) is not particularly limited, but is preferably 50 to 100% by mass, and more preferably 60 to 80% by mass when used for a base tread of a tire, for example. The amount of the bonded aromatic vinyl group in the modified conjugated diene polymer (i) is not particularly limited, but is preferably 0 to 50% by mass, more preferably 20 to 40% by mass. When the amount of the conjugated diene bonded and the amount of the aromatic vinyl bonded are within the above ranges, a sulfide excellent in the balance between low hysteresis loss and wet skid resistance and also excellent in abrasion resistance can be obtained. The amount of the bonded aromatic vinyl group can be determined by measuring the ultraviolet absorption of the phenyl group. Specifically, the measurement can be carried out by the method based on the examples described later.

The vinyl bond content in the conjugated diene bond unit is not particularly limited, but is preferably 10 to 75 mol%, more preferably 25 to 65 mol%. When the vinyl bond content is in the above range, a sulfide having an excellent balance between low hysteresis loss and wet skid resistance and also satisfying abrasion resistance can be obtained.

When the modified conjugated diene polymer (i) is a copolymer of butadiene and styrene, the vinyl bond amount (1, 2-bond amount) in the butadiene bond unit can be determined by the method of Hampton (r.r. Hampton, Analytical Chemistry,21,923 (1949)).

When the microstructure (the amount of each bonding in the modified conjugated diene copolymer (i)) is in the above range and the glass transition temperature of the copolymer is in the range of-45 to-15 ℃, a sulfide having a more excellent balance between low hysteresis loss properties and wet skid resistance can be obtained. As for the glass transition temperature, a DSC curve can be recorded while raising the temperature in a predetermined temperature range in accordance with ISO22768:2006, and the peak top (inflection point) of the DSC differential curve can be regarded as the glass transition temperature.

When the modified conjugated diene polymer (i) is a conjugated diene-aromatic vinyl copolymer, the number of blocks in which 30 or more aromatic vinyl units are linked is preferably small or none. Specifically, in the case where the copolymer is a butadiene-styrene copolymer, in a known method of decomposing a polymer by a Kolthoff method (the method described in i.m. Kolthoff, et al, j.polymer.sci.1, 429 (1946)), and analyzing the amount of polystyrene insoluble in methanol, a block segment in which 30 or more aromatic vinyl units are linked is preferably 5% by mass or less, more preferably 3% by mass or less, with respect to the total amount of the polymer.

In the present embodiment, the conjugated diene polymer (modified conjugated diene polymer) having a compound having a specific structure introduced by the reaction at the polymerization active end as a functional group can be further hydrogenated in an inert solvent to convert all or part of the double bonds into saturated hydrocarbons. The conjugated diene copolymer before modification may be hydrogenated, or the modified conjugated diene copolymer after modification may be hydrogenated. By hydrogenation, heat resistance and weather resistance can be improved, and deterioration of products during processing at high temperatures can be prevented. As a result, the composition exhibits more excellent performance in various applications such as automobile applications.

(method for producing modified conjugated diene Polymer (i))

The following describes a method for producing the modified conjugated diene polymer (i).

< polymerization step >

Preferred examples of the modified conjugated diene polymer (i) contained in the modified conjugated diene polymer composition of the present embodiment include: a modified conjugated diene polymer having a branched molecular structure with a nitrogen-containing epoxy substituent as a branching origin or a branched molecular structure with a nitrogen-containing alkoxysilane substituent as a branching origin.

In the method for producing a modified conjugated diene polymer, it is preferable that: for example, the polymerization step is carried out using a polyfunctional anionic polymerization initiator or a monofunctional anionic polymerization initiator as a polymerization initiator.

[ (a) Process for producing conjugated diene Polymer having active terminal in the case of Using polyfunctional anionic polymerization initiator ]

First, a polyfunctional anionic polymerization initiator used in the step of polymerizing the conjugated diene polymer at a stage before the polymerization active end of the conjugated diene polymer is modified with an alkoxysilane compound (modifier) described later will be described.

The polyfunctional anionic polymerization initiator used in the polymerization step of the conjugated diene polymer can be prepared by reacting a polyvinyl aromatic compound with an organolithium compound.

For example, the following methods can be mentioned: a method of reacting an organolithium compound with a polyvinyl aromatic compound in a hydrocarbon solvent; a method in which an organolithium compound is reacted with a conjugated diene compound, and then a polyvinyl aromatic compound is reacted; a method in which an organolithium compound is reacted with a monovinyl aromatic compound, and then a polyvinyl aromatic compound is reacted; and a method of reacting an organolithium compound in the presence of a conjugated diene compound and/or two or three of a monovinyl aromatic compound and a polyvinyl aromatic compound.

Particularly preferred are polyfunctional anionic polymerization initiators prepared by the following methods: a method of reacting an organolithium compound with a polyvinyl aromatic compound in a hydrocarbon solvent, a method of reacting a polyvinyl aromatic compound after reacting an organolithium compound with a conjugated diene compound, and a method of reacting a monoorganolithium compound in the presence of a conjugated diene compound and a polyvinyl compound.

In addition, in order to accelerate the generation of the polyfunctional anionic polymerization initiator and stabilize it, it is preferable to add a lewis base to the system in the preparation.

Examples of the polyvinyl aromatic compound used in the preparation of the polyfunctional anionic polymerization initiator include, but are not limited to, the following: for example, o-, m-and p-divinylbenzene, o-, m-and p-diisopropenylbenzene, 1,2, 4-trivinylbenzene, 1, 2-vinyl-3, 4-dimethylbenzene, 1, 3-divinylnaphthalene, 1,3, 5-trivinylnaphthalene, 2, 4-divinylbiphenyl, 3,5, 4' -trivinylbiphenyl, 1, 2-divinyl-3, 4-dimethylbenzene, 1,5, 6-trivinyl-3, 7-diethylnaphthalene, and the like.

These may be used alone or in combination of two or more.

Particular preference is given to divinylbenzene, diisopropenylbenzene and also mixtures of their ortho-, meta-and para-isomers.

In the preparation of the polyfunctional anionic polymerization initiator, a conjugated diene compound and/or a monoaromatic vinyl compound may be used together with the above-mentioned polyvinyl aromatic compound.

Examples of the conjugated diene compound include, but are not limited to, the following: for example, 1, 3-butadiene, isoprene, 2, 3-dimethyl-1, 3-butadiene, 1, 3-pentadiene, 3-methyl-1, 3-pentadiene, 1, 3-heptadiene, 1, 3-hexadiene and the like, and 1, 3-butadiene and isoprene are particularly preferable.

Further, examples of the monovinyl aromatic compound include, but are not limited to, the following: for example, styrene, p-methylstyrene, α -methylstyrene, vinylethylbenzene, vinylxylene, vinylnaphthalene and the like, with styrene being particularly preferred.

The conjugated diene compound and/or the monoaromatic vinyl compound are/is more preferably added so that the weight average molecular weight of the polyfunctional anionic polymerization initiator as measured by GPC is 1,000 to 10,000 in terms of polystyrene.

Examples of the organolithium compound used for the preparation of the polyfunctional anionic polymerization initiator include, but are not limited to, the following: examples of the organolithium compound include monoorganolithium compounds such as n-butyllithium, sec-butyllithium, tert-butyllithium, n-propyllithium, isopropyllithium and benzyllithium, and polyfunctional organolithium compounds such as 1, 4-dilithiobutane, 1, 5-dilithiopentane, 1, 6-dilithiohexane, 1, 10-dilithidecane, 1-dilithiophenyl, dilithiobutadiene, dilithiopolyprenyl, 1, 4-dilithiobenzene, 1, 2-dilithio-1, 2-diphenylethane, 1, 4-dilithio-2-ethylcyclohexane, 1,3, 5-trilithiobenzene and 1,3, 5-trilithio-2, 4, 6-triethylbenzene. Particularly preferred are mono-organolithium compounds such as n-butyllithium, sec-butyllithium, and tert-butyllithium.

Examples of the solvent used for the preparation of the polyfunctional anionic polymerization initiator include, but are not limited to, the following: aliphatic hydrocarbons such as butane, pentane, hexane, and heptane; alicyclic hydrocarbons such as cyclopentane and cyclohexane; aromatic hydrocarbons such as benzene, toluene, and xylene.

In addition, in the step of preparing the polyfunctional anionic polymerization initiator, it is effective to add a Lewis base into the system.

Examples of lewis bases include, but are not limited to, the following: for example, tertiary monoamines, tertiary diamines, linear ethers, cyclic ethers, and the like.

Examples of tertiary monoamines include, but are not limited to, the following: examples of the compound include trimethylamine, triethylamine, methyldiethylamine, 1-dimethoxytrimethylamine, 1-diethoxytrimethylamine, 1-diethoxytrimethylamine, N-dimethylformamide diisopropylacetal, and N, N-dimethylformamide dicyclohexylacetal.

Examples of tertiary diamines include, but are not limited to, the following: examples of the "N", N, N ', N' -tetramethyldiaminomethane ", N, N, N ', N' -tetramethylethylenediamine", N, N, N ', N' -tetramethylpropylenediamine, N, N, N ', N' -tetramethyldiaminobutane, N, N, N ', N' -tetramethyldiaminopentane, N, N, N ', N' -tetramethylhexamethylenediamine, dipiperidinoethane, and the like.

Examples of the chain ether include, but are not limited to, the following: for example, dimethyl ether, diethyl ether, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether.

Examples of the cyclic ether include, but are not limited to, the following: for example, tetrahydrofuran, bis (2-tetrahydrofuryl) ethane, 2-bis (2-tetrahydrofuryl) propane, 1-bis (2-tetrahydrofuryl) ethane, 2-bis (2-tetrahydrofuryl) butane, 2-bis (5-methyl-2-tetrahydrofuryl) propane, 2-bis (3,4, 5-trimethyl-2-tetrahydrofuryl) propane and the like.

Among the lewis bases mentioned above, trimethylamine and triethylamine as tertiary monoamines are preferable; n, N' -tetramethylethylenediamine as a tertiary diamine; and tetrahydrofuran, 2-bis (2-tetrahydrofuryl) propane, as cyclic ethers.

The lewis base may be used alone or in combination of two or more.

When the lewis base is added in the preparation of the polyfunctional anionic polymerization initiator, the lewis base is preferably added in the range of 30 to 50,000ppm, more preferably in the range of 200 to 20,000ppm, based on the solvent used in the preparation of the polymerization initiator.

The lewis base is preferably added in an amount of 30ppm or more in order to sufficiently exhibit the effect of promoting the reaction and stabilizing, and in view of ensuring the degree of freedom of microstructure adjustment in the subsequent polymerization step and the separation of the recovered solvent from the polymerization catalyst in the purification step after the polymerization, the lewis base is preferably added in an amount of 50,000ppm or less.

The polyfunctional anionic polymerization initiator used in the step of polymerizing the conjugated diene polymer is preferably adjusted so that the molar ratio of the polyvinyl aromatic compound to the organolithium is in the range of 0.01 to 1.0.

As the amount of the polyvinyl aromatic compound used relative to the organic lithium increases, the proportion of the molecular chain ends of the conjugated diene polymer to which functional groups are imparted by the modification reaction, which will be described later, increases, and the affinity and reactivity with the silica particles can be improved, so that the modified conjugated diene polymer composition of the present embodiment has a good balance between low hysteresis loss and wet skid resistance, and can also improve abrasion resistance.

On the other hand, when the amount of the polyvinyl aromatic compound used is small relative to the organic lithium compound, the processability in kneading the composition can be improved, and from this point of view, it is preferable that the amount of the polyvinyl aromatic compound is 1.0 mol or less relative to 1mol of the organic lithium compound.

In general, when the low hysteresis loss property is improved, the mooney viscosity of the composition tends to be increased and the processability tends to be deteriorated, and from the above-mentioned point of view, it is practically preferable that the amount of the polyvinyl aromatic compound to be used is not too large.

From the viewpoint of improving the balance of the above properties, the amount of the polyvinyl aromatic compound is more preferably in the range of 0.02 to 0.5 mol, and still more preferably in the range of 0.02 to 0.1 mol, based on 1mol of the organolithium compound.

The temperature for preparing the polyfunctional anionic polymerization initiator is preferably 10 ℃ or higher from the viewpoint of practical production, and is preferably 140 ℃ or lower, and more preferably in the range of 35 to 110 ℃ from the viewpoint of suppressing side effects caused by high temperature.

The reaction time for preparing the multifunctional anionic polymerization initiator is influenced by the reaction temperature and ranges from 5 minutes to 24 hours.

The conjugated diene polymer is obtained by anionic polymerization using the above-mentioned polyfunctional anionic polymerization initiator. In particular, a conjugated diene polymer having an active terminal obtained by a propagation reaction by living anionic polymerization is more preferable. Thus, the modified conjugated diene polymer (i) having a high modification ratio can be obtained by the modification step described later.

The polymerization method is not particularly limited, and a batch polymerization method, a continuous polymerization method, or the like can be used. In the continuous mode, 1 or 2 or more reactors connected to each other may be used. Any of reactors having known structures such as a tank type and a tubular type with a stirrer can be used as the reactor.

The weight average molecular weight (Mw) of the polyfunctional anionic polymerization initiator in terms of polystyrene measured by GPC is preferably in the range of 500 to 20,000, more preferably in the range of 1,000 to 10,000.

The modified conjugated diene polymer composition of the present embodiment using the conjugated diene polymer obtained using the polyfunctional anionic polymerization initiator having a molecular weight distribution in the above range has a reduced mooney viscosity, and can be a vulcanizate having an excellent balance between low hysteresis loss properties and wet skid resistance.

The conjugated diene polymer before modification to obtain the modified conjugated diene polymer (i) is obtained by copolymerizing a conjugated diene compound and an aromatic vinyl compound using the above-mentioned polyfunctional anionic polymerization initiator.

The conjugated diene polymer before modification or the modified conjugated diene polymer after modification obtained in the polymerization step may be hydrogenated as appropriate.

The hydrogenation method is not particularly limited, and a known method can be used. Particularly suitable hydrogenation methods include a method in which hydrogen gas is blown into a polymer solution in the presence of a catalyst to carry out hydrogenation.

Examples of the catalyst include heterogeneous catalysts such as a catalyst in which a noble metal is supported on a porous inorganic substance; a catalyst obtained by solubilizing a salt of nickel, cobalt or the like and reacting the solubilized salt with an organoaluminum or the like; homogeneous catalysts such as catalysts using metallocenes such as cyclopentadienyl titanium, and the like. Among these, the cyclopentadienyl titanium catalyst is preferable, in particular, from the viewpoint of enabling selection of mild hydrogenation conditions. In addition, hydrogenation of aromatic groups can be carried out by using a noble metal-supported catalyst.

Specific examples of the catalyst for hydrogenating unsaturated double bonds of the conjugated diene compound include, but are not limited to, the following: (A) a supported heterogeneous hydrogenation catalyst in which a metal such as Ni, Pt, Pd, or Ru is supported on carbon, silica, alumina, or diatomaceous earth; (B) a so-called ziegler-type hydrogenation catalyst which uses an organic acid salt such as Ni, Co, Fe, or Cr, or a transition metal salt such as an acetylacetone salt, and a reducing agent such as organoaluminum; (C) and so-called organometallic complexes such as organometallic compounds of Ti, Ru, Rh, Zr, etc. As the hydrogenation catalyst, hydrogenation catalysts described in Japanese patent publication No. 42-8704, Japanese patent publication No. 43-6636, Japanese patent publication No. 63-4841, Japanese patent publication No. 1-37970, Japanese patent publication No. 1-53851, Japanese patent publication No. 2-9041, and Japanese patent publication No. 8-109219 may be used. As a preferred hydrogenation catalyst, a reaction mixture of a cyclopentadienyl titanium compound and a reducing organometallic compound may be mentioned.

If the conjugated diene compound as the polymerization monomer contains impurities such as allenes and acetylenes, the modification reaction described later may be inhibited. Therefore, the total content concentration (mass) of these impurities is preferably 200ppm or less, more preferably 100ppm or less, and still more preferably 50ppm or less. Examples of the allenes include allene and 1, 2-butadiene. Examples of the acetylene include ethyl acetylene and vinyl acetylene.

The polymerization reaction of the conjugated diene polymer is preferably carried out in a solvent.

Examples of the solvent include, but are not limited to, the following: for example, a hydrocarbon solvent such as a saturated hydrocarbon or an aromatic hydrocarbon. Specific examples thereof include aliphatic hydrocarbons such as butane, pentane, hexane and heptane; alicyclic hydrocarbons such as cyclopentane, cyclohexane, methylcyclopentane, and methylcyclohexane; aromatic hydrocarbons such as benzene, toluene and xylene, and hydrocarbons composed of a mixture thereof.

Before the polymerization reaction, the treatment with an organic metal compound of allenes or acetylenes as impurities tends to obtain a polymer having a high concentration of active ends and further tends to achieve a high modification ratio, and therefore the treatment is preferably carried out.

In the polymerization reaction of the conjugated diene polymer, a polar compound may be added. The addition of the polar compound can cause the aromatic vinyl compound and the conjugated diene compound to undergo random copolymerization, or the polar compound can be used as a vinylating agent for controlling the microstructure of the conjugated diene portion. In addition, the polar compound is also effective in improving the polymerization rate and the like.

Examples of the polar compound include, but are not limited to, the following: ethers such as tetrahydrofuran, diethyl ether, dioxane, ethylene glycol dimethyl ether, ethylene glycol dibutyl ether, diethylene glycol dimethyl ether, diethylene glycol dibutyl ether, dimethoxybenzene, and 2, 2-bis (2-tetrahydrofuryl) propane; tertiary amine compounds such as tetramethylethylenediamine, dipiperidinoethane, trimethylamine, triethylamine, pyridine, and quinuclidine; metal alkoxide compounds such as potassium tert-butoxide, sodium tert-butoxide, and sodium pentoxide; phosphine compounds such as triphenylphosphine, and the like.

These polar compounds may be used alone or in combination of two or more.

The amount of the polar compound to be used is not particularly limited and may be selected according to the purpose. Usually, the amount of the polymerization initiator is preferably 0.01 to 100 moles based on 1 mole of the polymerization initiator. Such a polar compound (vinylating agent) can be used in an appropriate amount according to the desired vinyl bonding amount as a regulator of the microstructure of the conjugated diene portion of the conjugated diene polymer. Many polar compounds have an effective randomizing effect in the copolymerization of a conjugated diene compound and an aromatic vinyl compound at the same time, and can be used as a distribution regulator for the aromatic vinyl compound or a regulator for the styrene block amount. As a method for randomizing the conjugated diene compound and the aromatic vinyl compound, for example, a method of intermittently adding a part of 1, 3-butadiene in the middle of copolymerization as described in Japanese patent laid-open No. 59-140211 can be used.

The polymerization temperature in the polymerization step of the conjugated diene polymer is not particularly limited as long as it is a temperature at which living anionic polymerization can be carried out, and is preferably 0 ℃ or higher from the viewpoint of productivity, and is preferably 120 ℃ or lower from the viewpoint of sufficiently ensuring the reaction amount of the modifier with respect to the living terminal after termination of polymerization.

[ (b) method for producing conjugated diene Polymer having active end for polymerization Using monofunctional anionic polymerization initiator ]

Next, a method for producing a conjugated diene polymer having a polymerization active end in the case of using a monofunctional anionic polymerization initiator will be described.

As the above-mentioned monofunctional anionic polymerization initiator, preferable ones are, in particular, compounds having a carbon-lithium bond.

Examples of the compound having a carbon-lithium bond include, but are not limited to, the following: for example, n-butyllithium, sec-butyllithium, tert-butyllithium, n-hexyllithium, benzyllithium, phenyllithium, lithium stilbene, and the like. N-butyllithium and sec-butyllithium are preferable from the viewpoints of easiness of industrial availability and easiness of control of polymerization reaction.

These organic lithium compounds may be used alone or in the form of a mixture of 2 or more.

The above-mentioned monofunctional anionic polymerization initiator may be used in combination with other organic alkali metal compounds.

Examples of the other organic alkali metal compounds include, but are not limited to, the following: for example, an organic sodium compound, an organic potassium compound, an organic rubidium compound, an organic cesium compound, and the like. Specifically, sodium naphthalene, potassium naphthalene and the like can be mentioned. In addition, alkoxides, sulfonates, carbonates, and amides of lithium, sodium, potassium, and the like can be mentioned. In addition, other organometallic compounds may be used in combination.

As the above-mentioned monofunctional anionic polymerization initiator, an organic alkaline earth metal compound may also be used.

Examples of the organic alkaline earth metal compound include an organomagnesium compound, an organocalcium compound, and an organic strontium compound. In addition, compounds such as alkaline earth metal alkoxides, sulfonates, carbonates, and amides can also be used. These organic alkaline earth metal compounds may be used in combination with organic alkali metal compounds and other organometallic compounds.

In the case of production using the above-mentioned monofunctional anionic polymerization initiator, the conjugated diene polymer before modification of the modified conjugated diene polymer (i) is not particularly limited as long as it is a polymer of a conjugated diene compound or a (co) polymer with an aromatic vinyl compound, and is preferably a (co) polymer obtained by propagation through anionic polymerization.

In particular, the conjugated diene polymer is preferably a polymer having a living terminal obtained by a propagation reaction based on living anionic polymerization.

Thus, a modified conjugated diene polymer having a high modification ratio can be obtained. The polymerization method is not particularly limited, and a batch polymerization method, a continuous polymerization method, or the like can be used. In the continuous mode, 1 or 2 or more reactors connected to each other may be used. As the reactor, a tank type reactor with a stirrer, a tubular type reactor, or the like can be used.

Before being supplied to the polymerization reaction, it is preferable to treat allenes or acetylenes as impurities with an organometallic compound in the polymerization system, which treatment tends to give a polymer having a high concentration of active terminals, which tends to give a higher modification ratio.

Examples of the solvent include hydrocarbon solvents such as saturated hydrocarbons and aromatic hydrocarbons. Specific examples thereof include aliphatic hydrocarbons such as butane, pentane, hexane and heptane; alicyclic hydrocarbons such as cyclopentane, cyclohexane, methylcyclopentane, and methylcyclohexane; aromatic hydrocarbons such as benzene, toluene and xylene, and hydrocarbons composed of a mixture thereof.

As the polymerization initiator used in the polymerization step of the conjugated diene polymer, in addition to the above-mentioned polymerization initiator, "an organolithium compound having at least 1 nitrogen atom in the molecule" or "a polymerization initiator system comprising a compound having at least 1 nitrogen atom in the molecule and an organolithium compound" may be used.

The polymerization initiator system may be prepared in advance in a predetermined reactor as an organolithium compound having at least 1 nitrogen atom in the molecule, or may be supplied to a reactor for carrying out polymerization or copolymerization to be described later, and the organolithium may be reacted with the compound having at least 1 nitrogen atom in the molecule simultaneously with or before the polymerization or copolymerization.

As the "compound having at least 1 nitrogen atom in the molecule" used in the polymerization initiator system, compounds represented by the following general formulae (1) to (3) can be used.

[ CHEM 1]

In the above formula (1), R₁₀And R₁₁Each independently represents at least one selected from the group consisting of an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, and an aralkyl group having 6 to 20 carbon atoms.

R₁₀And R₁₁R in the case that R may be bonded to form a cyclic structure together with an adjacent nitrogen atom₁₀And R₁₁Represents an alkyl group having 5 to 12 carbon atoms, and may have an unsaturated bond or a branched structure in a part thereof.

[ CHEM 2]

In the above formula (2), R₁₂And R₁₃Each independently represents at least one of the group consisting of an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms and an aralkyl group having 6 to 20 carbon atoms.

R₁₂And R₁₃R in the case that R may be bonded to form a cyclic structure together with an adjacent nitrogen atom₁₂And R₁₃Represents an alkyl group having 5 to 12 carbon atoms, and may have an unsaturated bond or a branched structure in a part thereof. R₁₄Represents an alkylene group having 1 to 20 carbon atoms or a conjugated diene polymer having 1 to 20 carbon atoms. X represents a hydrogen atom, a Cl atom, a Br atom or an I atom.

[ CHEM 3]

In the above formula (3), R₁₅And R₁₆Each independently represents at least one of the group consisting of an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms and an aryl group having 6 to 20 carbon atoms.

R₁₅And R₁₆R in the case that R may be bonded to form a cyclic structure together with an adjacent nitrogen atom₁₅And R₁₆Represents an alkyl group having 5 to 12 carbon atoms, and may have a branched structure in a part thereof.

In the above formula (1), R is₁₀And R₁₁Examples of the group include, but are not limited to, methyl, ethyl, propyl, butyl, octyl, cyclopropyl, cyclohexyl, 3-phenyl-1-propyl, isobutyl, decyl, heptyl, and phenyl.

Examples of the compound represented by the formula (1) include, but are not limited to, dimethylamine, diethylamine, dibutylamine, dipropylamine, diheptylamine, dihexylamine, dioctylamine, di-2-ethylhexylamine, didecylamine, ethylpropylamine, ethylbutylamine, ethylbenzylamine, and methylphenethylamine.

The compounds represented by the above formula (1) are not limited to these, and include their analogs as long as the above conditions are satisfied.

The compound represented by the formula (1) is preferably dibutylamine or dihexylamine, and more preferably dibutylamine, from the viewpoints of reducing hysteresis loss of the modified conjugated diene polymer composition of the present embodiment, reducing an unpleasant odor of the modified conjugated diene polymer of the present embodiment, and controlling a chain transfer reaction described later.

R₁₀And R₁₁When the compound is bonded to form a cyclic structure together with an adjacent nitrogen atom, examples of the compound represented by the formula (1) include piperidine, hexamethyleneimine, azocane, 1,3, 3-trimethyl-6-azabicyclo [ 3.2.1%]Octane, 1,2,3, 6-tetrahydropyridine.

The compound represented by the above formula (1) is not limited to these, and includes analogs thereof as long as the above conditions are satisfied.

The compound represented by the formula (1) is preferably piperidine, hexamethyleneimine, azocane, 1,3, 3-trimethyl-6-azabicyclo [3.2.1] octane, more preferably piperidine, hexamethyleneimine, and still more preferably piperidine, from the viewpoints of reducing hysteresis loss of the modified conjugated diene polymer composition of the present embodiment, reducing an unpleasant odor of the modified conjugated diene polymer of the present embodiment, and controlling a chain transfer reaction described later.

In the formula (2), R is a group represented by the formula₁₄Preferably an alkyl group having 2 to 16 carbon atoms, more preferably an alkyl group having 3 to 10 carbon atoms.

Examples of the compound represented by the formula (2) include, but are not limited to, 3-chloro-dimethylpropan-1-amine, 3-chloro-diethylpropan-1-amine, 3-chloro-dibutylpropan-1-amine, 3-chloro-dipropylpropan-1-amine, 3-chloro-diheptylpropan-1-amine, 3-chloro-dihexylpropan-1-amine, 3-chloropropyl-ethylhexan-1-amine, 3-chloro-didecylpropan-1-amine, 3-chloro-ethylpropan-1-amine, 3-chloro-ethylbutan-1-amine, 3-chloro-ethylpropan-1-amine, and mixtures thereof, Benzyl-3-chloro-ethylpropan-1-amine, 3-chloro-ethylphenethylpropan-1-amine, 3-chloro-methylphenylethylpropan-1-amine, 1- (3-chloropropyl) piperidine, 1- (3-chloropropyl) hexamethyleneimine, 1- (3-chloropropyl) azocane, 6- (3-chloropropyl) -1,3, 3-trimethyl-6-azabicyclo [3.2.1] octane, 1- (3-chloropropyl) -1,2,3, 6-tetrahydropyridine, 1- (3-bromopropyl) hexamethyleneimine, 1- (3-iodopropyl) hexamethyleneimine, 1- (3-chlorobutyl) hexamethyleneimine, N-methyl-N-ethyl-1-aminotoluene-1-amine, N-methyl-3-chloropropyl-piperidine, N-methyl-3-chloropropyl-hexamethyleneimine, N-methyl-ethyl, 1- (3-chloropentyl) hexamethyleneimine, 1- (3-chlorohexyl) hexamethyleneimine, 1- (3-chlorodecyl) hexamethyleneimine.

The compound represented by the above formula (2) is not limited to these, and includes analogs thereof as long as the above conditions are satisfied.

The compound represented by the above formula (2) is preferably 3-chloro-dibutylpropane-1-amine or 1- (3-chloropropyl) hexamethyleneimine, more preferably 1- (3-chloropropyl) hexamethyleneimine, from the viewpoint of reactivity and interactivity with an inorganic filler such as carbon or silica.

In the above formula (2), R₁₄When the conjugated diene polymer has any one of the following repeating units (4) to (6), X represents a hydrogen atom.

[ CHEM 4]

[ CHEM 5]

[ CHEM 6]

When X in the above formula (2) represents a hydrogen atom, examples of the compound represented by the formula (2) include, but are not limited to, N, N-dimethyl-2-butenyl-1-amine, N, N-diethyl-2-butenyl-1-amine, N, N-dibutyl-2-butenyl-1-amine, N, N-dipropyl-2-butenyl-1-amine, N, N-diheptyl-2-butenyl-1-amine, N, N-dihexyl-2-butenyl-1-amine, N, N-dioctyl-2-butenyl-1-amine, N, N- (di-2-ethylhexyl) -2-butenyl-1-amine, N, N-tert-butyl-2-butenyl-1-amine, N, N-dimethyl-2-butenyl-1-amine, N, N-diethyl-2-butenyl-1-amine, N, N-dibutyl-2-, N, N-didecyl-2-butenyl-1-amine, N-ethylpropyl-2-butenyl-1-amine, N-ethylbutyl-2-butenyl-1-amine, N-ethylbenzyl-2-butenyl-1-amine, N-methylphenylethyl-2-butenyl-1-amine, N-dimethyl-2-methyl-2-butenyl-1-amine, N-diethyl-2-methyl-2-butenyl-1-amine, N-dibutyl-2-methyl-2-butenyl-1-amine, N, n-dipropyl-2-methyl-2-butenyl-1-amine, N-diheptyl-2-methyl-2-butenyl-1-amine, N-dihexyl-2-methyl-2-butenyl-1-amine, N-dimethyl-3-methyl-2-butenyl-1-amine, N-diethyl-3-methyl-2-butenyl-1-amine, N-dibutyl-3-methyl-2-butenyl-1-amine, N-dipropyl-2-methyl-2-butenyl-1-amine, N-di-methyl-3-butenyl-2-butenyl-1-amine, N-di-methyl-2-butenyl-, N, N-diheptyl-3-methyl-2-butenyl-1-amine, N-dihexyl-3-methyl-2-butenyl-1-amine, 1- (2-butenyl) piperidine, 1- (2-butenyl) hexamethyleneimine, 1- (2-butenyl) azocane, 6- (2-butenyl) 1,3, 3-trimethyl-6-azabicyclo [3.2.1] octane, 1- (2-butenyl) -1,2,3, 6-tetrahydropyridine, (2-methyl-2-butenyl) hexamethyleneimine, or (3-methyl-2-butenyl) hexamethyleneimine.

From the viewpoint of reducing the hysteresis loss of the modified conjugated diene polymer composition of the present embodiment, the compound represented by the formula (2) is preferably N, N-dibutyl-2-butenyl-1-amine or 1- (2-butenyl) hexamethyleneimine, more preferably 1- (2-butenyl) piperidine or 1- (2-butenyl) hexamethyleneimine, and still more preferably 1- (2-butenyl) piperidine.

Examples of the compound represented by the formula (3) include, but are not limited to, the following: for example, N, N-dimethyl-o-toluidine, N, N-dimethyl-m-toluidine, N, N-dimethyl-p-toluidine, N, N-diethyl-o-toluidine, N, N-diethyl-m-toluidine, N, N-diethyl-p-toluidine, N, N-dipropyl-o-toluidine, N, N-dipropyl-m-toluidine, N, N-dipropyl-p-toluidine, N, N-dibutyl-o-toluidine, N, N-dibutyl-m-toluidine, N, N-dibutyl-p-toluidine, o-piperidyl toluene, p-piperidyl toluene, o-pyrrolidinyl toluene, p-pyrrolidinyl toluene, N, N, N ', N' -tetramethyl-toluidine, N, N, N ', N' -tetraethyl-toluidine, N, N, N ', N' -tetrapropyl-toluidine, N, N-dimethyldimethylaniline, N-diethyldimethylaniline, N-dipropyldimethylaniline, N-dimethyltrimethylamine, N-diethyltrimethylamine, (N, N-dimethylamino) tolylphenylmethylamine, 1- (N, N-dimethylamino) -2-methylnaphthalene, 1- (N, N-dimethylamino) -2-methylanthracene.

The compound represented by the above formula (3) is not limited to these, and includes analogs thereof as long as the above conditions are satisfied.

The compound represented by the above formula (3) is preferably N, N-dimethyl-o-toluidine from the viewpoint of reducing hysteresis loss of a modified conjugated diene polymer composition described later.

In the polymerization initiator system, examples of the organic lithium compound to be combined with the compound having at least 1 nitrogen atom in the molecule include, but are not limited to, the following: for example, n-butyllithium, sec-butyllithium, tert-butyllithium, n-propyllithium, and isopropyllithium.

The organic lithium compound constituting the polymerization initiator system is an organic lithium compound having at least 1 nitrogen atom in the molecule and usable as a polymerization initiator for anionic polymerization, and preferably contains an organic lithium compound represented by any one of the following general formulae (7) to (10) from the viewpoint of improving the modification ratio and improving the fuel saving performance.

[ CHEM 7]

In the above formula (7), R₁₀And R₁₁Each independently represents at least one selected from the group consisting of an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, and an aralkyl group having 6 to 20 carbon atoms.

[ CHEM 8]

In the above formula (8), R₁₂And R₁₃Each independently represents at least one selected from the group consisting of an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, and an aralkyl group having 6 to 20 carbon atoms.

R₁₂And R₁₃R in the case that R may be bonded to form a cyclic structure together with an adjacent nitrogen atom₁₂And R₁₃Represents an alkyl group having 5 to 12 carbon atoms, and may have an unsaturated bond or a branched structure in a part thereof. R₁₄Represents an alkylene group having 1 to 20 carbon atoms or a conjugated diene polymer having 1 to 20 carbon atoms.

[ CHEM 9]

In the above formula (9), R₁₅And R₁₆Each independently represents at least one selected from the group consisting of an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, and an aryl group having 6 to 20 carbon atoms.

[ CHEM 10]

In the above formula (10), R₁₇The alkyl group has a cyclic structure formed together with a nitrogen atom and has 4 to 12 carbon atoms in total, and may have an unsaturated bond or a branched structure in a part thereof.

R₁₈Represents an alkyl group having 1 to 12 carbon atoms, and may have a branched structure in a part thereof.

In the above formula (7), R is₁₀And R₁₁Examples of the group include, but are not limited to, methyl, ethyl, propyl, butyl, octyl, silyl, ethylpropylamino, ethylbutylamino, ethylbenzylamino, and methylphenylethylamino.

R₁₀And R₁₁These are not limited to them, and their analogues are included as long as the above conditions are satisfied. From the viewpoint of solubility in a solvent, reduction of hysteresis loss of the modified conjugated diene polymer composition of the present embodiment, and control of a chain transfer reaction described later, dibutylamino group and dihexylamino group are preferable, and dibutylamino group is more preferable.

In the above formula (7), in R₁₀And R₁₁In the case where the bond is formed into a cyclic structure together with the adjacent nitrogen atom,examples of the organic lithium compound represented by the above formula (7) include, but are not limited to, the following: for example, lithium piperidide, lithium hexamethyleneimide, lithium azacyclooctane, lithium-1, 3, 3-trimethyl-6-azabicyclo [3.2.1]Octane, 1,2,3, 6-tetrahydropyridinyl lithium. The organolithium compound represented by formula (7) is not limited to these, and includes analogs thereof as long as the above conditions are satisfied. From the viewpoint of solubility of the polymerization initiator in a solvent, reduction of an unpleasant odor of the modified conjugated diene polymer of the present embodiment, and suppression of a chain transfer reaction, lithium piperidyl, lithium hexamethyleneimide, lithium azacyclooctane, lithium-1, 3, 3-trimethyl-6-azabicyclo [3.2.1]Octane, more preferably lithium piperidyl or lithium hexamethyleneimide, and still more preferably lithium piperidyl.

In the above formula (8), R₁₄As described above, the conjugated diene polymer is an alkylene group having 1 to 20 carbon atoms or a conjugated diene polymer having 1 to 20 carbon atoms.

Preferably, the conjugated diene polymer is a conjugated diene polymer having a repeating unit represented by any one of the following formulas (11) to (13).

[ CHEM 11]

[ CHEM 12]

[ CHEM 13]

In the above formula (8), in R₁₄When the alkylene group having 1 to 20 carbon atoms is represented, R is a group represented by R in terms of reactivity and interactivity with an inorganic filler such as carbon or silica₁₄Preferably alkylene having 2 to 16 carbon atomsThe group more preferably represents an alkylene group having 3 to 10 carbon atoms.

In addition, R₁₄When the organic lithium compound represents an alkylene group having 1 to 20 carbon atoms, examples of the organic lithium compound represented by the formula (8) include, but are not limited to, the following: for example, (3- (dimethylamino) -propyl) lithium, (3- (diethylamino) -propyl) lithium, (3- (dipropylamino) -propyl) lithium, (3- (dibutylamino) -propyl) lithium, (3- (dipentylamino) -propyl) lithium, (3- (dihexylamino) -propyl) lithium, (3- (dioctylamino) -propyl) lithium, (3- (ethylhexylamino) -propyl) lithium, (3- (didecylamino) -propyl) lithium, (3- (ethylpropylamino) -propyl) lithium, (3- (ethylbutylamino) -propyl) lithium, (3- (ethylbenzylamino) -propyl) lithium, (3- (methylphenylethylamino) -propyl) lithium, lithium, (4- (dibutylamino) -butyl) lithium, (5- (dibutylamino) -pentyl) lithium, (6- (dibutylamino) -hexyl) lithium, (10- (dibutylamino) -decyl) lithium.

The organic lithium compound represented by the above formula (8) is not limited to these, and includes analogs thereof as long as the above conditions are satisfied. From the viewpoint of reactivity and interactivity with an inorganic filler such as carbon or silica, (3- (dibutylamino) -propyl) lithium is more preferable.

In the above formula (8), in R₁₄When the conjugated diene polymer having the repeating units represented by the formulae (11) to (13) is represented, examples of the organolithium compound represented by the formula (8) include, but are not limited to, the following: for example, (4- (dimethylamino) -2-butenyl) lithium, (4- (diethylamino) -2-butenyl) lithium, (4- (dibutylamino) -2-butenyl) lithium, (4- (dipropylamino) -2-butenyl) lithium, (4- (diheptylamino) -2-butenyl) lithium, (4- (dihexylamino) -2-butenyl) lithium, (4- (dioctylamino) -2-butenyl) lithium, (4- (di-2-ethylhexylamino) -2-butenyl) lithium, (4- (didecylamino) -2-butenyl) lithium, (4- (ethylpropylamino) -2-butenyl) lithium, lithium (4-tert-butylamino) -2-butenyl) lithium, lithium (4-propylamino) -2-butenyl) lithium, lithium (4-tert-butylamino) -lithium (4-propylamino) -2-butenyl) lithium, lithium (4-butyl, (4- (ethylbutylamino) -2-butenyl) lithium, (4- (ethylbenzylamino) -2-butenyl) lithium, (4- (methylphenylethylamino) -2-butenyl) lithium, (4- (dimethylamino) -2-methyl-2-butenyl) lithium, (4- (diethylamino) -2-methyl-2-butenyl) lithium, and (4- (dibutylamino) -2-methyl-2-butenyl) lithiumPhenylamino) -2-methyl-2-butenyl) lithium, (4- (dipropylamino) -2-methyl-2-butenyl) lithium, (4- (diheptylamino) -2-methyl-2-butenyl) lithium, (4- (dihexylamino) -2-methyl-2-butenyl) lithium, (4- (dimethylamino) -3-methyl-2-butenyl) lithium, (4- (diethylamino) -3-methyl-2-butenyl) lithium, (4- (dibutylamino) -3-methyl-2-butenyl) lithium, (4- (dipropylamino) -3-methyl-2-butenyl) lithium, lithium, Lithium (4- (diheptylamino) -3-methyl-2-butenyl) and lithium (4- (dihexylamino) -3-methyl-2-butenyl).

The organic lithium compound represented by the above formula (8) is not limited to these, and includes analogs thereof as long as the above conditions are satisfied. From the viewpoint of reactivity as a polymerization initiator and the viewpoint of controlling a chain transfer reaction described later, 4- (dimethylamino) -2-butenyl) lithium, (4- (diethylamino) -2-butenyl) lithium, and (4- (dibutylamino) -2-butenyl) lithium are preferable, and (4- (dibutylamino) -2-butenyl) lithium is more preferable.

In the above formula (8), in R₁₂And R₁₃When the organic lithium compound is bonded to form a cyclic structure together with an adjacent nitrogen atom, examples of the organic lithium compound represented by the formula (8) include, but are not limited to, the following: for example, (3- (piperidinyl) propyl) lithium, (3- (hexamethyleneimino) propyl) lithium, (3- (heptamethyleneimino) propyl) lithium, (3- (octamethyleneimino) propyl) lithium, (3- (1,3, 3-trimethyl-6-azabicyclo [3.2.1] lithium]Octyl) propyl) lithium, (3- (1,2,3, 6-tetrahydropyridyl) propyl) lithium, (2- (hexamethyleneimino) ethyl) lithium, (4- (hexamethyleneimino) butyl) lithium, (5- (hexamethyleneimino) pentyl) lithium, (6- (hexamethyleneimino) hexyl) lithium, (10- (hexamethyleneimino) decyl) lithium, (4- (piperidyl) -2-butenyl) lithium, (4- (hexamethyleneimino) -2-butenyl) lithium, (4- (heptamethyleneimino) -2-butenyl) lithium, (4- (octamethyleneimino) -2-butenyl) lithium, and (4- (1,3, 3-trimethyl-6-azabicyclo [ 3.2.1).]Octyl) -2-butenyl) lithium, (4- (1,2,3, 6-tetrahydropyridyl) -2-butenyl) lithium, (4- (hexamethyleneimino) -2-methyl-2-butenyl) lithium, (4- (hexamethyleneimino) -3-methyl-2-butenyl) lithium.

The organic lithium compound represented by the above formula (8) is not limited to these, and includes analogs thereof as long as the above conditions are satisfied. From the viewpoint of reactivity and interactivity with an inorganic filler such as carbon or silica, and from the viewpoint of controlling a chain transfer reaction described later, (3- (piperidyl) propyl) lithium, (3- (hexamethyleneimino) propyl) lithium, (3- (1,2,3, 6-tetrahydropyridinyl) propyl) lithium is preferable, (4- (piperidyl) -2-butenyl) lithium and (4- (hexamethyleneimino) -2-butenyl) lithium, more preferably (3- (hexamethyleneimino) propyl) lithium, (4- (piperidyl) -2-butenyl) lithium and (4- (hexamethyleneimino) -2-butenyl) lithium, and still more preferably (4- (piperidyl) -2-butenyl) lithium.

Examples of the organolithium compound represented by the above formula (9) include, but are not limited to, the following: for example, lithium N, N-dimethyl-o-tolylamide, lithium N, N-dimethyl-m-tolylamide, lithium N, N-dimethyl-p-tolylamide, lithium N, N-diethyl-o-tolylamide, lithium N, N-diethyl-m-tolylamide, lithium N, N-diethyl-p-tolylamide, lithium N, N-dipropyl-o-tolylamide, lithium N, N-dipropyl-m-tolylamide, lithium N, N-dipropyl-p-tolylamide, lithium N, N-dibutyl-o-tolylamide, lithium N, N-dibutyl-p-tolylamide, lithium o-piperidyl-tolyl, lithium p-piperidyl-tolyl, lithium o-pyrrolidinyltolyl, lithium p-pyrrolidinyltolyl, lithium N, N, N ', N' -tetramethyltolylamide, N, n, N ', N' -tetraethyltoluenediaminium, N, N, N ', N' -tetrapropyltoluenediaminium, N, N-dimethylxylenediaminium, N, N-diethylxylenediaminium, N, N-dipropylxylenediaminium, N, N-dimethylmesitylenediaminium, N, N-diethylmesitylenediaminium, lithium (N, N-dimethylamino) tolylmethylaminium, lithium 1- (N, N-dimethylamino) -2-methylnaphthyl, lithium 1- (N, N-dimethylamino) -2-methylanthrenyl.

The organic lithium compound represented by the above formula (9) is not limited to these, and includes analogs thereof as long as the above conditions are satisfied. From the viewpoint of polymerization activity, lithium N, N-dimethyl-o-tolylamide is more preferable.

Examples of the organolithium compound represented by the above formula (10) include, but are not limited to, the following: for example, 2- (2-methylpiperidinyl) -1-ethyllithium (for example, trade name "AI-250" manufactured by FMC corporation).

The organic lithium compound represented by the above formula (10) is not limited to these, and includes analogs thereof as long as the above conditions are satisfied.

The organic lithium compound having at least 1 nitrogen atom in the molecule may be prepared in advance as the polymerization initiator before the state of the modified conjugated diene polymer (i), that is, before the polymerization step of the conjugated diene polymer, and any known method may be employed for the preparation method.

The organolithium compound having at least 1 nitrogen atom in the molecule represented by the above formula (7) is obtained, for example, by reacting the compound represented by the above formula (1) with an organolithium compound in a hydrocarbon solvent. As the hydrocarbon solvent, an appropriate solvent such as hexane, cyclohexane, benzene, etc. may be selected. The reaction temperature is preferably 0 ℃ to 80 ℃ and, from the viewpoint of productivity, preferably 5.0 ℃ to 70 ℃, more preferably 7.0 ℃ to 50 ℃.

An organolithium compound having at least 1 nitrogen atom in the molecule represented by the above formula (8) in R₁₄When the alkylene group has 1 to 20 carbon atoms, the compound can be obtained as follows: for example, a compound represented by the above formula (2) is reacted with an organolithium compound in a hydrocarbon solvent to prepare an aminolithium compound, and a dihalogenated alkyl group represented by the following formula (a) is reacted with the aminolithium compound, and further reacted with an organolithium compound, thereby obtaining an organolithium compound having at least 1 nitrogen atom in the molecule represented by the above formula (8).

[ CHEM 14]

X¹-R^3a-X² (A)

In the above formula (A), X¹And X²Each independently represents an I atom, a Br atom or a Cl atom, R^3aThe alkylene group has 1 to 20 carbon atoms, preferably 2 to 16 carbon atoms, and more preferably 3 to 10 carbon atoms.

Examples of the compound represented by the formula (a) include, but are not limited to, the following: for example, 1-bromo-3-chloropropane, 1-bromo-4-chlorobutane, 1-bromo-5-chloropentane, 1-bromo-6-chlorohexane, 1-bromo-10-chlorodecane, 1-bromo-3-iodopropane, 1-bromo-4-iodobutane, 1-bromo-5-iodopentane, 1-bromo-6-iodohexane, 1-bromo-10-iododecane, 1-chloro-3-iodopropane, 1-chloro-4-iodobutane, 1-chloro-5-iodopentane, 1-chloro-6-iodohexane, 1-chloro-10-iododecane.

The compound represented by the formula (A) is preferably 1-bromo-3-chloropropane, 1-bromo-4-chlorobutane, 1-bromo-5-chloropentane, 1-bromo-6-chlorohexane, or 1-bromo-10-chlorodecane, and more preferably 1-bromo-3-chloropropane, 1-bromo-4-chlorobutane, or 1-bromo-6-chlorohexane, from the viewpoints of reactivity and safety.

The reaction temperature in the production of the lithium amide compound using the compound represented by the above formula (2), the organolithium compound and the hydrocarbon solvent is preferably from-78 ℃ to 70 ℃. The reaction temperature when the compound represented by the formula (A) is reacted with the lithium amide compound is preferably from-78 ℃ to 70 ℃, more preferably from-50 ℃ to 50 ℃. Thereafter, the reaction temperature in the reaction of the organolithium compound with the obtained compound is preferably from-78 ℃ to 70 ℃ inclusive, and more preferably from-50 ℃ to 50 ℃ inclusive.

The compound represented by formula (9) can be produced using the compound represented by formula (3), an organolithium compound, and a hydrocarbon solvent. The reaction temperature in the production of the lithium amide compound is preferably from-78 ℃ to 70 ℃.

An organolithium compound having at least 1 nitrogen atom in the molecule represented by the above formula (8) in R₁₄When a conjugated diene polymer having a repeating unit represented by any one of the above formulas (11) to (13) is represented, it is synthesized by the following steps (I) to (IV).

(I) The method comprises the following steps A compound represented by the formula (2) is reacted with an organolithium compound in a hydrocarbon solvent to synthesize an aminolithium compound.

(II): the resulting lithium amide compound is reacted with butadiene or isoprene in a hydrocarbon solvent.

(III): an alcohol was added to deactivate lithium, and the resultant product was distilled under reduced pressure.

(IV): the product obtained by distillation is reacted with an organolithium compound in a hydrocarbon solvent.

The reaction temperature in the above step (I) for producing lithium amide using the compound represented by the above formula (2), the organolithium compound and the hydrocarbon solvent is as described above.

The alcohol in the step (III) may be a general alcohol, preferably a low molecular weight alcohol, for example, methanol, ethanol, isopropanol, and more preferably ethanol.

The reaction temperature in the step (IV) is 0 ℃ to 80 ℃ inclusive, preferably 10 ℃ to 70 ℃ inclusive.

In the preparation of the organic lithium compound, a polar compound may be added to the system. There is a tendency that the formation of the organolithium compound is promoted and the organolithium compound is solubilized in the hydrocarbon solvent. Examples of the polar compound include, but are not limited to, the following: for example, tertiary monoamines, tertiary diamines, linear ethers or cyclic ethers.

Examples of tertiary monoamines include, but are not limited to, the following: for example, trimethylamine, triethylamine, methyldiethylamine, 1-dimethoxytrimethylamine, 1-diethoxytrimethylamine, 1-diethoxytetraethylamine, N-dimethylformamide diisopropylacetal, N-dimethylformamide dicyclohexylacetal.

Examples of tertiary diamines include, but are not limited to, the following: for example, N, N, N ', N' -tetramethyldiaminomethane, N, N, N ', N' -tetramethylethylenediamine, N, N, N ', N' -tetramethylpropanediamine, N, N, N ', N' -tetramethyldiaminobutane, N, N, N ', N' -tetramethyldiaminopentane, N, N, N ', N' -tetramethylhexanediamine, dipiperidinopentane, dipiperidinoethane.

Examples of the cyclic ether include, but are not limited to, the following: for example, tetrahydrofuran, bis (2-tetrahydrofuryl) ethane, 2-bis (2-tetrahydrofuryl) propane, 1-bis (2-tetrahydrofuryl) ethane, 2-bis (2-tetrahydrofuryl) butane, 2-bis (5-methyl-2-tetrahydrofuryl) propane, 2-bis (3,4, 5-trimethyl-2-tetrahydrofuryl) propane.

Among the polar compounds, trimethylamine and triethylamine as tertiary monoamines are preferable; n, N' -tetramethylethylenediamine as a tertiary diamine; tetrahydrofuran and 2, 2-bis (2-tetrahydrofuryl) propane are used as cyclic ethers. The polar compound may be used alone or in combination of 2 or more.

When the polar compound is added in the production of the organolithium compound as the polymerization initiator, the polar compound is preferably added in a range of 30 mass ppm or more and 50,000 mass ppm or less, and more preferably in a range of 200 mass ppm or more and 20,000 mass ppm or less, relative to the solvent used in the production. In order to sufficiently exhibit the effect of promoting the reaction and the effect of solubilizing in the solvent, the polar compound is preferably added in an amount of 30 mass ppm or more, and in view of ensuring the degree of freedom of microstructure adjustment in the polymerization step and the separation from the polymerization solvent in the purification step after the recovery of the solvent after the polymerization, the polar compound is preferably added in an amount of 50,000 mass ppm or less.

The conjugated diene polymer before modification of the modified conjugated diene polymer (i) can be obtained as follows: the conjugated diene polymer before modification of the modified conjugated diene polymer (i) is obtained by polymerizing a conjugated diene compound using the above-mentioned various polymerization initiators (preferably, an organolithium compound having at least 1 nitrogen atom in the molecule), or a polymerization initiator system comprising a compound having at least 1 nitrogen atom and an organolithium compound, or copolymerizing a conjugated diene compound and an aromatic vinyl compound.

In the polymerization step, an organolithium compound having at least 1 nitrogen atom in the molecule may be prepared in advance in a predetermined reactor and supplied to a reactor for polymerization of the conjugated diene compound or copolymerization of the conjugated diene compound and the aromatic vinyl compound, or the compound having at least 1 nitrogen atom in the molecule and the organolithium compound may be mixed by using a static mixer or an in-line mixer to prepare the compound and the polymerization reaction may be carried out simultaneously. When the above-mentioned organolithium compound having at least 1 nitrogen atom in the molecule is used as the polymerization initiator, only one kind of the compound may be used alone, or a mixture of 2 or more kinds may be used.

The conjugated diene polymer before modification can be obtained by the following polymerization step: the polymerization is carried out using the above-mentioned polymerization initiator system comprising a compound having at least 1 nitrogen atom in the molecule and an organolithium compound, using a conjugated diene compound, or copolymerizing the conjugated diene compound with an aromatic vinyl compound.

The polymerization step of the conjugated diene polymer may be carried out by any of batch-wise and continuous polymerization methods, and from the viewpoint of stably producing a conjugated diene polymer having a high modification ratio, a high molecular weight, and a high branching degree, the polymerization is preferably carried out by a continuous method, and more preferably by a continuous method in 1 reactor or 2 or more reactors connected in series.

In this case, in order to set the modification rate to 75% by mass or more and the MSR (stress relaxation rate) to 0.45 or less, it is preferable that the polymerization temperature be 45 ℃ to 80 ℃ inclusive and the solid content (solid content) be 16.0% by mass or less, for example.

In order to achieve a modification ratio of 78 mass% or more and an MSR of 0.45 or less, it is preferable to control the polymerization temperature in the range of 50 ℃ to 80 ℃ and to achieve a solid content of 16.0 mass% or less.

In order to control the modification ratio to 80 mass% or more and the MSR to 0.44 or less, it is preferable to control the polymerization temperature to 50 ℃ to 80 ℃ inclusive and to control the solid content to 16.0 mass% or less, and the composition of the organolithium compound to be supplied is preferably 0.001mol/L or less with respect to the hydrocarbon solvent.

In order to achieve a modification ratio of 85 mass% or more and an MSR of 0.43 or less, it is preferable to control the polymerization temperature to 50 ℃ to 78 ℃ inclusive, to achieve a solid content of 16.0 mass% or less, and to achieve a feed composition of the organolithium compound of 0.001mol/L or less with respect to the hydrocarbon solvent.

In order to achieve a modification ratio of 88 mass% or more and an MSR of 0.42 or less, it is preferable that the polymerization temperature is 55 ℃ to 76 ℃ inclusive, the solid content is 15.0 mass% or less, and the feed composition of the organolithium compound is 0.0008mol/L or less relative to the hydrocarbon solvent.

More preferably, the polymerization is a continuous polymerization in which the modification rate is 90 mass% or more and the MSR is 0.40 or less, that is, a high modification rate, a high molecular weight and a high degree of branching are achieved by appropriately controlling the chain transfer reaction described later, the polymerization temperature is 60 ℃ to 72 ℃ inclusive, the solid content is 14.0 mass% or less, the organolithium compound is continuously added, and the composition of the organolithium compound to be supplied is preferably 0.00070mol/L or less relative to the hydrocarbon solvent.

The polymerization process of the polymer using the organolithium compound may be a continuous process or a batch process, and from the viewpoint of production efficiency, a continuous process in which a monomer containing the conjugated diene compound and a polymerization initiator are continuously supplied to a polymerization reactor and polymerization is continuously performed is preferred. In the case of the continuous system, the monomer, the solvent and the polymerization initiator used for the polymerization may be supplied to the polymerization vessel separately, or may be mixed continuously by using a mixing tank equipped with a stirrer or by using a static mixer or an inline mixer in the piping.

From the viewpoint of stability of the organolithium compound, the monomer and the polymerization initiator used in the polymerization are preferably diluted with a hydrocarbon solvent. The monomer preferably has a solid content of 16 mass% or less. When the polymerization initiator is an organolithium compound, the composition of the organolithium compound to be supplied is preferably 0.0010mol/L or less, more preferably 0.0008mol/L or less, relative to the hydrocarbon solvent.

In the polymerization step, from the viewpoint of stable production of a high molecular weight polymer, the polymerization system is preferably a continuous system, and the amount of the organolithium compound is preferably 0.0010mol/L or less relative to the hydrocarbon solvent.

In the polymerization step of the conjugated diene polymer before modification of the modified conjugated diene polymer (i), when a polymerization initiator system comprising a compound having at least 1 nitrogen atom in the molecule and an organolithium compound is used to polymerize a copolymer of a conjugated diene compound and an aromatic vinyl compound, the chain transfer reaction is accelerated by the influence of at least 1 nitrogen atom in the molecule of the polymerization initiator system as described in makromol. chem 186.1335-1350(1985), and therefore, the active terminal tends to be deactivated, and specific production conditions are required to increase the modification ratio. Further, for example, when the polymerization temperature is increased, the chain transfer rate or the chain transfer rate increases, the number average molecular weight of the obtained polymer decreases, the branching degree increases, the molecular weight distribution becomes broad, and a block portion in which 30 or more aromatic vinyl units are linked tends to decrease or not exist, and therefore, the MSR (stress relaxation rate) tends to decrease. However, it was observed that the deactivation of the active terminal was promoted, and the modification ratio tended to decrease without controlling the production conditions. In the batch polymerization method and the continuous polymerization method, the chain transfer reaction tends to further proceed in the continuous polymerization method.

The polymerization temperature is not particularly limited as long as it is within a temperature range in which anionic polymerization can be carried out, chain transfer reaction is controlled, and the number of blocks in which 30 or more aromatic vinyl compound units are linked is small or nonexistent, but is preferably 45 ℃ or more from the viewpoint of productivity, more preferably 80 ℃ or less from the viewpoint of controlling the chain transfer reaction and sufficiently ensuring the reaction amount of the modifier with the active end after termination of polymerization, and even more preferably 50 ℃ or more and 78 ℃ or less from the viewpoint of reducing the number of blocks in which 30 or more aromatic vinyl compound units are linked, and even more preferably 60 ℃ or more and 75 ℃ or less.

In the polymerization step, from the viewpoint of controlling the chain transfer reaction, the content of the conjugated diene compound, the aromatic vinyl compound and the like, that is, the solid content is preferably 16 mass% or less, more preferably 15 mass% or less, and still more preferably 14 mass% or less, with respect to the total mass of the conjugated diene compound, the aromatic vinyl compound and the solvent. The upper limit of the solid content is not particularly limited, but is preferably 12.5 mass% or more.

In the polymerization step, it is preferable that the polymerization system is a continuous type from the viewpoint of controlling the chain transfer reaction and suppressing the deactivation of the active terminals, the polymerization temperature is 45 ℃ to 80 ℃ and the solid content is 16 mass% or less.

The conjugated diene compound used in the polymerization step is not particularly limited, and examples thereof include 1, 3-butadiene, isoprene, 2, 3-dimethyl-1, 3-butadiene, 1, 3-pentadiene, 3-methyl-1, 3-pentadiene, 1, 3-heptadiene, and 1, 3-hexadiene. Among these, 1, 3-butadiene and isoprene are preferable from the viewpoint of easy industrial availability. These substances may be used not only in 1 kind but also in 2 or more kinds in combination. 1, 3-butadiene is particularly preferred.

The aromatic vinyl compound as a monomer used in the polymerization step may be any monomer copolymerizable with the conjugated diene compound, and examples thereof include, but are not limited to, the following: for example, styrene, p-methylstyrene, alpha-methylstyrene, vinylethylbenzene, vinylxylene, vinylnaphthalene, diphenylethylene. Among these, styrene is preferred in view of easy industrial availability. These substances may be used not only in 1 kind but also in 2 or more kinds in combination.

The polymerization step is preferably carried out in a solvent. Examples of the solvent include hydrocarbon solvents such as saturated hydrocarbons and aromatic hydrocarbons. Specific examples of the hydrocarbon solvent include, but are not limited to, the following: aliphatic hydrocarbons such as butane, pentane, hexane, and heptane; alicyclic hydrocarbons such as cyclopentane, cyclohexane, methylcyclopentane, and methylcyclohexane; aromatic hydrocarbons such as benzene, toluene, xylene, and the like, and hydrocarbons composed of a mixture thereof.

Before the conjugated diene compound, the aromatic vinyl compound and the polymerization solvent are supplied to the polymerization reaction separately or in advance as a mixed solution thereof, it is preferable to treat the organic metal compound by reacting the organic metal compound with the allenes and the acetylenes as impurities.

This prevents the occurrence of polymerization inhibition due to impurities, and the active end amount of the polymer is high, whereby a narrower molecular weight distribution (Mw/Mn) can be achieved, and a higher modification ratio tends to be achieved.

In the polymerization reaction of the conjugated diene polymer, a polar compound may be added. Thus, the following tendency is exhibited: the aromatic vinyl compound and the conjugated diene compound can be randomly copolymerized, and the polar compound can be used as a vinylating agent for controlling the microstructure of the conjugated diene portion. Further, the polymerization rate can be improved.

Examples of the polar compound include, but are not limited to, the following: ethers such as tetrahydrofuran, diethyl ether, dioxane, ethylene glycol dimethyl ether, ethylene glycol dibutyl ether, diethylene glycol dimethyl ether, diethylene glycol dibutyl ether, dimethoxybenzene, and 2, 2-bis (2-tetrahydrofuryl) propane; tertiary amine compounds such as tetramethylethylenediamine, dipiperidinoethane, trimethylamine, triethylamine, pyridine, and quinuclidine; alkali metal alkoxide compounds such as potassium tert-butoxide, sodium tert-butoxide, and sodium pentoxide; phosphine compounds such as triphenylphosphine.

These polar compounds may be used alone or in combination of 2 or more.

The amount of the polar compound to be used is not particularly limited, and may be selected according to the purpose, and is preferably 0.01 to 100 moles based on 1 mole of the polymerization initiator. Such a polar compound (vinylating agent) as a regulator of the microstructure of the conjugated diene portion of the polymer can be used in an appropriate amount depending on the desired vinyl bonding amount. Many polar compounds have an effective randomizing effect in copolymerization of a conjugated diene compound and an aromatic vinyl compound at the same time, and tend to be useful as a distribution regulator for an aromatic vinyl compound or a regulator for the amount of styrene blocks.

As a method for randomizing a conjugated diene compound and an aromatic vinyl compound, for example, a method of intermittently adding a part of 1, 3-butadiene in the middle of copolymerization is disclosed in Japanese patent laid-open No. 59-140211.

The amount of the bonded conjugated diene in the conjugated diene polymer before modification of the modified conjugated diene polymer (i) is not particularly limited, but is preferably 50% by mass or more and 100% by mass or less, and more preferably 60% by mass or more and 80% by mass or less. The amount of the bonded aromatic vinyl group in the conjugated diene polymer is not particularly limited, but is preferably 0 mass% to 50 mass%, more preferably 20 mass% to 40 mass%. When the amount of the conjugated diene bonded and the amount of the aromatic vinyl bonded are within the above ranges, a sulfide having a further excellent balance between low hysteresis loss and wet skid resistance and further satisfactory abrasion resistance and fracture strength tends to be obtained. The amount of the bonded aromatic vinyl group can be determined by measuring the ultraviolet absorption of the phenyl group, and the amount of the bonded conjugated diene can be determined. Specifically, the measurement can be carried out by the method described in the examples described later.

The vinyl bond amount in the conjugated diene bond unit is not particularly limited, but is preferably 10 mol% or more and 75 mol% or less, and more preferably 25 mol% or more and 65 mol% or less. When the vinyl bond content is in the above range, a sulfide having a further excellent balance between low hysteresis loss and wet skid resistance and further satisfactory abrasion resistance and fracture strength tends to be obtained. When the modified conjugated diene polymer is a copolymer of butadiene and styrene, the vinyl bond amount (1, 2-bond amount) in the butadiene bond unit can be determined by the Hampton method (r.r. Hampton, Analytical Chemistry,21,923 (1949)). Specifically, the measurement can be carried out by the method described in the examples described later.

The conjugated diene polymer before modification of the modified conjugated diene polymer (i) may be a random copolymer or a block copolymer. Examples of random copolymers include, but are not limited to, the following: for example, butadiene-isoprene random copolymer, butadiene-styrene random copolymer, isoprene-styrene random copolymer, butadiene-isoprene-styrene random copolymer.

The composition distribution of each monomer in the copolymer chain is not particularly limited, and examples thereof include a completely random copolymer having a nearly statistically random composition and a tapered (gradient) random copolymer having a tapered composition. The composition of the bonding pattern (i.e., 1, 4-bonding, 1, 2-bonding, etc.) of the conjugated diene may be uniform or may have a distribution.

Examples of the block copolymer include, but are not limited to, the following: for example, a 2-type block copolymer composed of 2 blocks, a 3-type block copolymer composed of 3 blocks, and a 4-type block copolymer composed of 4 blocks. For example, when a block made of an aromatic vinyl compound such as styrene is represented by S and a block made of a conjugated diene compound such as butadiene or isoprene and/or a block made of a copolymer of an aromatic vinyl compound and a conjugated diene compound is represented by B, the block copolymer may be represented by an S-B2 type block copolymer, an S-B-S3 type block copolymer, an S-B-S-B4 type block copolymer, or the like.

In the above formula, the boundaries of the blocks are not necessarily clearly distinguished from each other. For example, when the block B is a copolymer of an aromatic vinyl compound and a conjugated diene compound, the aromatic vinyl compound in the block B may be uniformly distributed or may be distributed in a tapered manner. In the block B, 2 or more portions in which the aromatic vinyl compound is uniformly distributed and/or 2 or more portions in which the aromatic vinyl compound is gradually distributed may coexist. In the block B, 2 or more segments having different aromatic vinyl compound contents may coexist. When the copolymer contains 2 or more blocks S and B, the structures such as the molecular weight and the composition thereof may be the same or different.

The conjugated diene polymer obtained by the above-mentioned production method can be further hydrogenated in an inert solvent to convert all or a part of the double bonds thereof into saturated hydrocarbons. In this case, heat resistance and weather resistance are improved, and deterioration of the product during processing at high temperature can be prevented. As a result, the composition can exhibit more excellent performance in various applications such as automobile applications.

The hydrogenation ratio of the unsaturated double bonds based on the conjugated diene compound (also simply referred to as "hydrogenation ratio") may be arbitrarily selected depending on the purpose, and is not particularly limited. When the rubber composition is used as a vulcanized rubber, it is preferable that a part of the double bonds of the conjugated diene portion remain. From this point of view, the hydrogenation ratio of the conjugated diene portion in the polymer is preferably 3.0% or more and 70% or less, more preferably 5.0% or more and 65% or less, and further preferably 10% or more and 60% or less. The hydrogenation ratio of the aromatic double bonds based on the aromatic vinyl compound in the copolymer of the conjugated diene compound and the aromatic vinyl compound is not particularly limited, but is preferably 50% or less, more preferably 30% or less, and still more preferably 20% or less. The hydrogenation rate can be determined by a nuclear magnetic resonance apparatus (NMR).

The hydrogenation method is not particularly limited, and a known method can be used. A suitable hydrogenation method is a method in which hydrogen gas is blown into a polymer solution in the presence of a catalyst to carry out hydrogenation.

Examples of the hydrogenation catalyst include, but are not limited to, the following: for example, (1) a supported heterogeneous hydrogenation catalyst in which a metal such as Ni, Pt, Pd, Ru, or the like is supported on carbon, silica, alumina, diatomaceous earth, or the like; (2) a so-called ziegler-type hydrogenation catalyst which uses an organic acid salt such as Ni, Co, Fe, or Cr, or a transition metal salt such as an acetylacetone salt, and a reducing agent such as organoaluminum; (3) so-called organometallic complexes such as organometallic compounds of Ti, Ru, Rh, Zr, etc.

Further, examples of the hydrogenation catalyst include hydrogenation catalysts described in Japanese patent publication No. 42-8704, Japanese patent publication No. 43-6636, Japanese patent publication No. 63-4841, Japanese patent publication No. 1-37970, Japanese patent publication No. 1-53851, Japanese patent publication No. 2-9041, and Japanese patent publication No. 8-109219.

As a preferred hydrogenation catalyst, a reaction mixture of a cyclopentadienyl titanium compound and a reducing organometallic compound may be mentioned.

If the conjugated diene compound contains impurities such as allenes and acetylenes, the modification reaction described later may be inhibited. Therefore, the total content concentration (mass) of these impurities is preferably 200 mass ppm or less and 100 mass ppm or less, and more preferably 50 mass ppm or less, with respect to the total amount of the conjugated diene compound. Examples of the allenes include allene and 1, 2-butadiene. Examples of the acetylene include ethyl acetylene and vinyl acetylene.

When the microstructure (the amount of each bond in the modified conjugated diene copolymer (i)) is in the above range and the glass transition temperature of the copolymer is in the range of-45 ℃ to-15 ℃, a sulfide having a more excellent balance between low hysteresis loss properties and wet skid resistance can be obtained.

As for the glass transition temperature, a DSC curve can be recorded while raising the temperature in a predetermined temperature range in accordance with ISO22768:2006, and the peak top (inflection point) of the DSC differential curve can be regarded as the glass transition temperature. Specifically, the measurement was carried out by the method described in the examples described later.

When the modified conjugated diene polymer (i) used in the present embodiment is a copolymer of a conjugated diene compound and an aromatic vinyl compound, the number of blocks in which 30 or more aromatic vinyl units are linked is preferably small or none. Specifically, in the case where the copolymer is a butadiene-styrene copolymer, in a known method of decomposing a polymer by a Kolthoff method (the method described in i.m. Kolthoff, et al, j.polymer.sci.1, 429 (1946)), and analyzing the amount of polystyrene insoluble in methanol, a block segment in which 30 or more aromatic vinyl units are linked is preferably 5.0 mass% or less, more preferably 3.0 mass% or less, with respect to the total amount of the polymer.

< modification step >

The modified conjugated diene polymer (i) can be obtained by obtaining a conjugated diene polymer having a polymerization active end by the above-mentioned method, and then performing a modification step by reacting a predetermined modifier at the polymerization active end.

The modified conjugated diene polymer (i) is preferably obtained by performing a modification step, described later, in which a compound (modifier) having a nitrogen atom and 2 or more epoxy groups in the molecule is reacted, or a compound (modifier) having an alkoxy group bonded to a silyl group in the molecule and a nitrogen atom is reacted.

In the modification step, the epoxy group of the compound (modifier) having a nitrogen atom and an epoxy group in the molecule is reacted with the polymerization active terminal of the conjugated diene polymer to form a bond between the polymerization active terminal of the conjugated diene and the oxygen atom of the ring-opened epoxy group.

In addition, the silyl group-bonded alkoxy group of the compound (modifier) having an alkoxy group bonded to a silyl group and a nitrogen atom in the molecule reacts with the polymerization active end of the conjugated diene polymer to form a bond between the end of the conjugated diene polymer and Si. Thus, the modified conjugated diene polymer has a branched molecular structure having a nitrogen-containing epoxy substituent or a nitrogen-containing alkoxysilane substituent as a branching origin.

[ modifier ]

First, as a compound (modifier) having a nitrogen atom and 2 epoxy groups in a molecule, for example, a compound represented by general formula (14) can be given.

[ CHEM 15]

In the general formula (14), R¹⁹、R²⁰Is a hydrocarbon group having 1 to 10 carbon atoms or a hydrocarbon group having 1 to 10 carbon atoms and having an ether group and/or a tertiary amine; r²¹、R²²Is hydrogen, a hydrocarbon group having 1 to 20 carbon atoms, or a hydrocarbon group having 1 to 20 carbon atoms and having an ether and/or a tertiary amine; r²³A hydrocarbon group having 1 to 20 carbon atoms or a hydrocarbon group having 1 to 20 carbon atoms and having at least one group selected from an ether, a tertiary amine, an epoxy, a carbonyl group and a halogen; k is 1 to 6.

As the modifier represented by the general formula (14), preferred are compounds wherein k is 2 or 3, and examples thereof include tetraglycidyl m-xylylenediamine, tetraglycidyl aminodiphenylmethane, tetraglycidyl p-phenylenediamine, diglycidylaminomethylcyclohexane, tetraglycidyl-1, 3-bisaminomethylcyclohexane, and the like.

Examples of the compound (modifier) having an alkoxy group bonded to a silyl group in a molecule and a nitrogen atom include compounds represented by general formulae (15), (16) and (17).

[ CHEM 16]

In the general formula (15), R²⁴、R²⁵Each independently is an alkyl group having 1 to 20 carbon atoms or an aryl group; r²⁶Is an alkylene group having 1 to 20 carbon atoms; r²⁷、R²⁸The carbon atoms can be the same or different, and are alkyl with 1-6 carbon atoms, and adjacent 2N together form a ring structure with more than 5-membered rings; r²⁹Is a hydrocarbon group having 1 to 20 carbon atoms or a silyl group having three organic substituents; p is an integer of 2 or 3.

[ CHEM 17]

In the general formula (16), R³¹～R³⁴Each independently represents an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms; r³⁵Represents an alkylene group having 1 to 10 carbon atoms; r³⁶Represents an alkylene group having 1 to 20 carbon atoms. m is an integer of 1 or 2, and n is an integer of 2 or 3.

[ CHEM 18 ]

In the general formula (17), R⁴⁸～R⁵⁰Each independently represents a single bond or an alkylene group having 1 to 20 carbon atoms; r⁵¹～R⁵⁴And R⁵⁶Each independently of the otherAnd (b) is an alkyl group having 1 to 20 carbon atoms; r⁵⁵And R⁵⁸Each independently represents an alkylene group having 1 to 20 carbon atoms; r⁵⁷An alkyl group having 1 to 20 carbon atoms or a trialkylsilyl group; v represents an integer of 1 to 3, and w represents 1 or 2. Each of R in the case of 2 or more⁴⁸～R⁵⁸V and w may be the same or different, independently of each other. d represents an integer of 0 to 6, e represents an integer of 0 to 6, f represents an integer of 0 to 6, and (d + e + f) is an integer of 3 to 10. Y represents a hydrocarbon group having 1 to 20 carbon atoms, or an organic group having at least one atom selected from the group consisting of an oxygen atom, a nitrogen atom, a silicon atom, a sulfur atom and a phosphorus atom and having no active hydrogen. The hydrocarbon group represented by Y includes saturated, unsaturated, aliphatic and aromatic hydrocarbon groups. The organic group having no active hydrogen is an organic group which renders the active terminal of the conjugated diene polymer inactive. Examples of such organic groups include those having no hydroxyl group (-OH), a secondary amino group(s) (OH)>NH), primary amino group (-NH)₂) And mercapto groups (-SH), etc.

In the above general formula (17), Y is represented by any one of the following general formulae (D) to (G).

[ CHEM 19 ]

In the general formula (D), Z¹Represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, and i represents an integer of 1 to 10. B in case of two or more¹Each independently.

[ CHEM 20 ]

In the general formula (E), Z²Z represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms³Represents an alkyl group having 1 to 20 carbon atoms, and i represents an integer of 1 to 10. In the case where there are two or more of eachZ²And Z³Each independently.

[ CHEM 21 ]

In the general formula (F), Z⁴Represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, and i represents an integer of 1 to 10. Z in the case where two or more⁴Each independently.

[ CHEM 22 ]

In the general formula (G), Z⁵Represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, and i represents an integer of 1 to 10. Z in the case where two or more⁵Each independently.

Examples of the modifier represented by the above general formula (15) include, but are not limited to, the following: for example, 1- [3- (triethoxysilyl) propyl ] -4-methylpiperazine, 1- [3- (diethoxyethylsilyl) propyl ] -4-methylpiperazine, 1- [3- (trimethoxysilyl) propyl ] -3-methylimidazolidine, 1- [3- (diethoxyethylsilyl) propyl ] -3-ethylimidazolidine, 1- [3- (triethoxysilyl) propyl ] -3-methylhexahydropyrimidine, 1- [3- (dimethoxymethylsilyl) propyl ] -3-methylhexahydropyrimidine, 3- [3- (tributoxysilyl) propyl ] -1-methyl-1, 2,3, 4-tetrahydropyrimidine, 3- [3- (dimethoxymethylsilyl) propyl ] -1-ethyl-1, 2,3, 4-tetrahydropyrimidine, 1- (2-ethoxyethyl) -3- [3- (trimethoxysilyl) propyl ] imidazolidine, (2- {3- [3- (trimethoxysilyl) propyl ] tetrahydropyrimidin-1-yl } ethyl) dimethylamine, 1- [3- (triethoxysilyl) propyl ] -4- (trimethylsilyl) piperazine, 1- [3- (dimethoxymethylsilyl) propyl ] -4- (trimethylsilyl) piperazine, 1- [3- (tributoxysilyl) propyl ] -4- (trimethylsilyl) piperazine, a salt thereof, a hydrate thereof, and a, 1- [3- (diethoxyethylsilyl) propyl ] -3- (triethylsilyl) imidazolidine, 1- [3- (triethoxysilyl) propyl ] -3- (trimethylsilyl) imidazolidine, 1- [3- (dimethoxymethylsilyl) propyl ] -3- (trimethylsilyl) hexahydropyrimidine, 1- [3- (triethoxysilyl) propyl ] -3- (trimethylsilyl) hexahydropyrimidine, 1- [4- (triethoxysilyl) butyl ] -4- (trimethylsilyl) piperazine, and the like.

Among these, 1- [3- (triethoxysilyl) propyl ] -4-methylpiperazine, 1- [3- (trimethoxysilyl) propyl ] -3-methylimidazolidine, 1- [3- (triethoxysilyl) propyl ] -3-methylhexahydropyrimidine, 1- [3- (triethoxysilyl) propyl ] -4- (trimethylsilyl) piperazine, 1- [3- (triethoxysilyl) propyl ] -3- (trimethylsilyl) imidazolidine, 1- [3- (triethoxysilyl) propyl ] -3- (trimethylsilyl) hexahydropyrimidine are preferable from the viewpoint of reactivity and interactivity between the functional group and an inorganic filler such as silica, more preferred are 1- [3- (triethoxysilyl) propyl ] -4-methylpiperazine and 1- [3- (triethoxysilyl) propyl ] -4- (trimethylsilyl) piperazine.

Examples of the modifier represented by the above general formula (16) include, but are not limited to, the following: for example, 2, 2-dimethoxy-1- (3-trimethoxysilylpropyl) -1-aza-2-silacyclopentane, 2, 2-diethoxy-1- (3-triethoxysilylpropyl) -1-aza-2-silacyclopentane, 2, 2-dimethoxy-1- (4-trimethoxysilylbutyl) -1-aza-2-silacyclohexane, 2, 2-dimethoxy-1- (5-trimethoxysilylpentyl) -1-aza-2-silacycloheptane, 2, 2-dimethoxy-1- (3-dimethoxymethylsilylpropyl) -1-aza-2-silacyclopentane, 2-methoxy-1- (3-triethoxysilylpropyl) -1-aza-2-silacyclopentane, and mixtures thereof, 2, 2-diethoxy-1- (3-diethoxyethylsilylpropyl) -1-aza-2-silacyclopentane, 2-methoxy, 2-methyl-1- (3-trimethoxysilylpropyl) -1-aza-2-silacyclopentane, 2-ethoxy, 2-ethyl-1- (3-triethoxysilylpropyl) -1-aza-2-silacyclopentane, 2-methoxy, 2-methyl-1- (3-dimethoxymethylsilylpropyl) -1-aza-2-silacyclopentane, 2-ethoxy, 2-ethyl-1- (3-diethoxyethylsilylpropyl) -1-aza-2-silacyclopentane Silacyclopentane, and the like.

Among these, those having m of 2 and n of 3 are more preferable from the viewpoint of rolling resistance characteristics and extrusion processability. Specifically, 2-dimethoxy-1- (3-trimethoxysilylpropyl) -1-aza-2-silacyclopentane, 2-diethoxy-1- (3-triethoxysilylpropyl) -1-aza-2-silacyclopentane are preferable.

Examples of the modifier represented by the general formula (17) include, but are not limited to, the following: for example, tris (3-trimethoxysilylpropyl) amine, tris (3-triethoxysilylpropyl) amine, tris (3-tripropoxysilylpropyl) amine, bis (3-trimethoxysilylpropyl) - [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] amine, tetrakis (3-trimethoxysilylpropyl) -1, 3-propanediamine, tris (3-trimethoxysilylpropyl) - [3- (1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl ] -1, 3-propanediamine, tris (3-trimethoxysilylpropyl) - [3- (1-methoxy-2-methyl-1-sila-pentan-yl) -2-azacyclopentane) propyl ] -1, 3-propanediamine, bis (3-triethoxysilylpropyl) - [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl ] - [3- (1-ethoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl ] -1, 3-propanediamine, tetrakis (3-trimethoxysilylpropyl) -1, 3-bisaminomethylcyclohexane, tris (3-trimethoxysilylpropyl) - [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] -1, 3-bisaminomethylcyclohexane, tetrakis (3-trimethoxysilylpropyl) -1, 6-hexanediamine, pentakis (3-trimethoxysilylpropyl) -diethylenetriamine, tris (3-trimethoxysilylpropyl) -methyl-1, 3-propanediamine, tetrakis [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] silane, bis (3-trimethoxysilylpropyl) -bis [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] silane, tris [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] - (3-trimethoxysilylpropyl) silane, bis (3-methoxy-1-aza-2-silacyclopentane) propyl ] - (3-trimethoxysilylpropyl) silane, bis (2-methoxy-1-aza-2-silacyclopentane) propyl ] (iii) silane, bis, Tris [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] - [3- (1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl ] silane, 3-tris [2- (2, 2-dimethoxy-1-aza-2-silacyclopentane) ethoxy ] silyl-1-trimethoxysilylpropane, 1- [3- (1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl ] -3,4, 5-tris (3-trimethoxysilylpropyl) -cyclohexane, and mixtures thereof, 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-silacyclopentane) propyl ] - (3- Trimethoxysilylpropyl) phosphate and tris [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] phosphate.

Examples of the modifier in the case where Y is represented by the formula (D) in the formula (17) include, but are not limited to, the following: for example, tris (3-trimethoxysilylpropyl) amine, bis (3-trimethoxysilylpropyl) - [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] amine, bis [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] - (3-trimethoxysilylpropyl) amine, tris [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] amine, tris (3-ethoxysilylpropyl) amine, bis (3-triethoxysilylpropyl) - [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl ] amine, bis (3-trimethoxysilylpropyl) - [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl ] amine, bis (trimethoxysilylpropyl) amine, bis (3-methoxy-1-aza-2-silacyclopentane) propyl ] amine, bis (3-trimethoxy, Bis [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) 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-trimethylsilyl-1-sila-2-azacyclopentane) propyl ] -1, 3-propanediamine, tris [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] - [3- (1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl ] ] -1, 3-propanediamine, tetrakis (3-triethoxysilylpropyl) -1, 3-propanediamine, tris (3-triethoxysilylpropyl) - [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl ] -1, 3-propanediamine, bis (3-triethoxysilylpropyl) -bis [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl ] -1, 3-propanediamine, tris [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl ] - (3-triethoxysilylpropyl) -1, 3-propanediamine, tetrakis [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl ] -1, 3-propanediamine, tris (3-triethoxysilylpropyl) - [3- (1-ethoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl ] -1, 3-propanediamine, bis (3-triethoxysilylpropyl) - [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl ] - [3- (1-ethoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl ] -1, 3-propanediamine, bis [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl ] - (3-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-trimethoxysilylpropyl) - [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] -1, 3-bisaminomethylcyclohexane, bis (3-trimethoxysilylpropyl) -bis [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] -1, 3-bisaminomethylcyclohexane, tris [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] - (3-trimethoxysilylpropyl) -1, 3-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, bis (3-methoxy-1-aza-2-azacyclopentane) propyl ] -1, 3-bisaminomethylcyclohexane, bis (3-methoxy-2-aza-2-sila-2-azacyclopentane) propyl ester, bis (3-methoxy-1-methoxy-, Tetrakis (3-triethoxysilylpropyl) -1, 3-propanediamine, tris (3-triethoxysilylpropyl) - [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl ] -1, 3-bisaminomethylcyclohexane, bis (3-triethoxysilylpropyl) -bis [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl ] -1, 3-bisaminomethylcyclohexane, tris [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl ] - (3-triethoxysilylpropyl) -1, 3-propanediamine, tri (3-triethoxysilylpropyl) -1, 3-propanediamine, and mixtures thereof, 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-bisaminomethylcyclohexane, bis (3-triethoxysilylpropyl) - [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl ] - [3- (1-ethoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl ] -1, 3-bisaminomethylcyclohexane, bis [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl ] - (3-triethoxysilylpropyl) - [3- (1-ethoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl ] -1, 3-bisaminomethylcyclohexane, tris [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl ] - [3- (1-ethoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl ] -1, 3-bisaminomethylcyclohexane, bis (3-ethoxysilylpropyl) - [1- (2-ethoxy-2-sila-2-azacyclopentane) propyl ] -1, 3-bisaminomethylcyclohexane, bis (3-triethoxy-1-aza-2-sila-2-azacyclopentane) propyl ] -, Tetrakis (3-trimethoxysilylpropyl) -1, 6-hexanediamine and pentakis (3-trimethoxysilylpropyl) -diethylenetriamine.

Examples of the modifier in the case where Y in the general formula (17) is represented by the general formula (E) include, but are not limited to, the following: for example, tris (3-trimethoxysilylpropyl) -methyl-1, 3-propanediamine, bis (2-trimethoxysilylpropyl) - [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl]-methyl-1, 3-propanediamine, bis [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl]- (3-trimethoxysilylpropyl) -methyl-1, 3-propanediamine, tris (3-triethoxysilylpropyl) -methyl-1, 3-propanediamine, bis (2-triethoxysilylpropyl) - [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl]-methyl-1, 3-propanediamine, bis [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl]- (3-triethoxysilylpropyl) -methyl-1, 3-propanediamine, N¹,N^1’- (propane-1, 3-diyl) bis (N)¹-methyl-N³,N³Bis (3- (trimethoxysilyl) propyl) -1, 3-propanediamine) and N¹- (3- (bis (3- (trimethoxysilyl) propyl) amino) propyl) -N¹-methyl-N³- (3- (methyl (3- (trimethoxysilyl) propyl) amino) propyl) -N³- (3- (trimethoxysilyl) propyl) -1, 3-propanediamine.

Examples of the modifier in the case where Y is represented by formula (F) in general formula (17) include, but are not limited to, the following: for example, tetrakis [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] silane, tris [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] - (3-trimethoxysilylpropyl) silane, tris [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] - [3- (1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl ] silane, bis (3-trimethoxysilylpropyl) -bis [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] silane, bis (3-trimethoxysilylpropyl) silane, tris (3-methoxy-1-aza-2-silacyclopentane) propyl ] silane, tris (2-methoxy-1-aza-2-silacyclopentane) propyl) silane, tris (2-methoxy-1-aza-2-sila, (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 (2, 2-methoxy-methyl-1-aza-2-silacyclopentane) propyl ] silane, bis (, 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.

Examples of the modifier in the case where Y in the general formula (17) is represented by the general formula (G) include, but are not limited to, the following: for example, 3-tris [2- (2, 2-dimethoxy-1-aza-2-silacyclopentane) ethoxy ] silyl-1- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propane and 3-tris [2- (2, 2-dimethoxy-1-aza-2-silacyclopentane) ethoxy ] silyl-1-trimethoxysilylpropane.

Among the modifiers of the general formula (17), those wherein Y is represented by the general formula (D) or the general formula (E) and f is 0 are preferred. Such a modifier tends to be easily available, and when the modified conjugated diene polymer is used as a vulcanizate, the modifier tends to be more excellent in abrasion resistance and low hysteresis loss performance.

Examples of such modifiers include, but are not limited to, the following: for example, bis (3-trimethoxysilylpropyl) - [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] amine, tris (3-trimethoxysilylpropyl) amine, tris (3-triethoxysilylpropyl) amine, tris (3-trimethoxysilylpropyl) - [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] -1, 3-propanediamine, tetrakis (3-trimethoxysilylpropyl) -1, 3-propanediamine, bis (methyl) silylpropyl ] -1, 3-propanediamine, bis (trimethoxysilylpropyl) amine, tris (3-methoxy-1-aza-2, Tetrakis (3-trimethoxysilylpropyl) -1, 3-bisaminomethylcyclohexane, tris (3-trimethoxysilylpropyl) -methyl-1, 3-propanediamine, and bis [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] - (3-trimethoxysilylpropyl) -methyl-1, 3-propanediamine.

In the modifier of the general formula (17), Y is more preferably represented by the general formula (D) or the general formula (E), f is 0, and i in the general formula (D) or the general formula (E) is an integer of 2 to 10. Therefore, the wear resistance and the low hysteresis loss performance after vulcanization tend to be more excellent.

Examples of such modifiers include, but are not limited to, the following: for example, tetrakis [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl]1, 3-propanediamine, tetrakis (3-trimethoxysilylpropyl) -1, 3-bisaminomethylcyclohexane and N¹- (3- (bis (3- (trimethoxysilyl) propyl) amino) propyl) -N¹-methyl-N³- (3- (methyl (3- (trimethoxysilyl) propyl) amino) propyl) -N³- (3- (trimethoxysilyl) propyl) -1, 3-propanediamine.

The reaction temperature, reaction time and the like in the reaction of the modifier with the polymerization active end of the conjugated diene polymer are not particularly limited, and the reaction is preferably carried out at 0 to 20 ℃ for 30 seconds or more.

The amount of the compound represented by the general formula (17) added can be adjusted so that the mole number of the conjugated diene polymer is reacted with the mole number of the modifier at a desired stoichiometric ratio, and thus a desired degree of branching tends to be achieved. The specific mole number of the polymerization initiator is preferably 5.0 times or more, and more preferably 6.0 times or more, relative to the mole number of the modifier. In this case, in the general formula (17), the number of functional groups ((v-1). times.d + wXe + f) of the modifier is preferably an integer of 5 to 10, more preferably an integer of 6 to 10.

In the above-mentioned modifier other than the general formula (17), the total mole number of the epoxy groups or the total mole number of the alkoxy groups bonded to the silyl group in the compound is preferably in the range of 0.8 to 3 times the mole number of the anion polymerization initiator to be added, more preferably in the range of 1 to 2.5 times the mole number of the anion polymerization initiator to be added, and still more preferably in the range of 1 to 2 times the mole number of the anion polymerization initiator to be added.

In order to obtain a sufficient modification ratio of the modified conjugated diene polymer (i) obtained, it is preferable that the number of moles of the anionic polymerization initiator added is 0.8 times or more, and in order to improve the extrusion processability, it is preferable that the polymer terminals are coupled to each other to obtain a branched polymer component, and in addition, from the viewpoint of the cost of the modifier, it is preferable that the number of moles of the anionic polymerization initiator added is 3 times or less.

In the method for producing the modified conjugated diene polymer, after the modification reaction, a deactivator, a neutralizer or the like may be added to the solution of the polymer as necessary.

Examples of the deactivator include water; alcohols such as methanol, ethanol, and isopropanol. Examples of the neutralizing agent include organic acids such as stearic acid, oleic acid, and neodecanoic acid; aqueous solutions of inorganic acids, carbon dioxide, and the like.

In addition, in the modified conjugated diene polymer, a rubber stabilizer is preferably added from the viewpoint of preventing gel formation in the completion step after polymerization and improving stability during processing. The rubber stabilizer is not particularly limited, and known ones can be used, and for example, 2, 6-di-tert-butyl-4-hydroxytoluene (BHT), n-octadecyl 3- (4 ' -hydroxy-3 ', 5 ' -di-tert-butylphenol) propionate, 2-methyl-4, 6-bis [ (octylthio) methyl ] phenol, and the like are preferable.

Examples of the modified conjugated diene polymer having a branched molecular structure having a nitrogen-containing epoxy substituent as a branching origin produced in the above manner include compounds represented by the following general formula (18).

[ CHEM 23 ]

In the general formula (18), (Polym) is a polymer chain, R¹⁹～R²³And k is as defined for formula (14).

The modified conjugated diene polymer represented by the general formula (18) is particularly preferably a compound having k of 2 or 3, and examples thereof include tetraglycidyl m-xylylenediamine, tetraglycidyl aminodiphenylmethane, tetraglycidyl p-phenylenediamine, diglycidylaminomethylcyclohexane, tetraglycidyl-1, 3-bisaminomethylcyclohexane, and the like.

Examples of the modified conjugated diene polymer having a branched molecular structure with a nitrogen-containing alkoxysilane substituent as a branching origin produced in the above manner include compounds represented by the following general formulae (19), (20), and (21).

[ CHEM 24 ]

In the general formula (19), (Polym) is a polymer chain, R²⁵～R²⁹And p has the same meaning as in the general formula (15).

[ CHEM 25 ]

In the general formula (20), (Polym) is a polymer chain, R³²～R³⁶M and n are as defined for formula (16).

[ CHEM 26 ]

In the above general formula (21), (Polym) represents a diene polymer chain, R⁶¹～R⁶³Each independently represents a single bond or an alkylene group having 1 to 20 carbon atoms, R⁶⁴And R⁶⁷Each independently represents an alkyl group having 1 to 20 carbon atoms, R⁶⁵、R⁶⁸And R⁶⁹Each independently represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms, R⁶⁶And R⁷⁰Each independently represents an alkylene group having 1 to 20 carbon atoms, R⁷¹Represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms. v and K each independently represent an integer of 1 to 3, K ≦ v, w represents 1 or 2, L represents an integer of 1 to 3, L ≦ (w +1), and M represents an integer of 1 or 2. (Polym) in the case where two or more of each exist)、R⁶¹～R⁷¹V, w, K, L and M are independent of each other, and may be the same or different. d represents an integer of 0 to 6, e represents an integer of 0 to 6, f represents an integer of 0 to 6, (d + e + f) is an integer of 3 to 10, and ((K × d) + (L × e) + (M × K)) is an integer of 5 to 30. Y represents a hydrocarbon group having 1 to 20 carbon atoms, or an organic group having at least one atom selected from the group consisting of an oxygen atom, a nitrogen atom, a silicon atom, a sulfur atom and a phosphorus atom and having no active hydrogen.

In the general formula (21), Y is preferably represented by any one of the following general formulae (D) to (G).

[ CHEM 27 ]

In the general formula (D), Z¹Represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, and i represents an integer of 1 to 10. Z in the case where two or more¹Each independently.

[ CHEM 28 ]

In the above general formula (E), Z²Z represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms³Represents an alkyl group having 1 to 20 carbon atoms, and i represents an integer of 1 to 10. Z in the case where two or more Z exist each²And Z³Each independently.

[ CHEM 29 ]

In the above general formula (F), Z⁴Represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, and i represents an integer of 1 to 10. Z in the case where two or more⁴Each independently.

[ CHEM 30 ]

In the above general formula (G), Z⁵Represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, and i represents an integer of 1 to 10. Z in the case where two or more⁵Each independently.

(rubber component other than the conjugated diene Polymer (i))

The modified conjugated diene polymer composition of the present embodiment may contain, in addition to the modified conjugated diene polymer (i) described above, another rubber-like polymer as a rubber component in a range that satisfies the characteristics of the present embodiment.

Examples of such a rubbery polymer include, but are not limited to, the following: for example, a conjugated diene polymer or a hydrogenated product thereof, a random copolymer of a conjugated diene compound and a vinyl aromatic compound or a hydrogenated product thereof, a block copolymer of a conjugated diene compound and a vinyl aromatic compound or a hydrogenated product thereof, a non-diene polymer, a natural rubber, and the like.

Specific examples thereof include styrene-based elastomers such as natural rubber, butadiene rubber or a hydrogenated product thereof, isoprene rubber or a hydrogenated product thereof, styrene-butadiene block copolymer or a hydrogenated product thereof, styrene-isoprene block copolymer or a hydrogenated product thereof, and nitrile rubber or a hydrogenated product thereof. Examples of the non-diene polymer include olefin elastomers such as ethylene-propylene rubber, ethylene-propylene-diene rubber, ethylene-butene rubber, ethylene-hexene rubber, and ethylene-octene rubber, butyl rubber, bromobutyl rubber, acrylic rubber, fluorine rubber, silicone rubber, chlorinated polyethylene rubber, epichlorohydrin rubber, α, β -unsaturated nitrile-acrylate-conjugated diene copolymer rubber, urethane rubber, and polysulfide rubber.

The various rubbery polymers described above may be modified rubbers to which a functional group having polarity such as a hydroxyl group or an amino group is added in addition to the modified conjugated diene polymer (i). The weight average molecular weight is preferably 2,000 to 2,000,000, more preferably 5,000 to 1,500,000, from the viewpoint of balance between performance and processing characteristics. In addition, so-called liquid rubbers of low molecular weight can also be used. These rubbery polymers may be used alone, or 2 or more kinds may be used in combination.

In the modified conjugated diene polymer composition of the present embodiment, the content ratio of the modified conjugated diene polymer (i) in the rubber component is preferably 5 to 100% by mass, more preferably 5 to 75% by mass, even more preferably 20 to 70% by mass, and even more preferably 30 to 70% by mass. When the content ratio of the modified conjugated diene polymer (i) in the rubber component is in the above range, a composition having an excellent balance between extrusion processability and rolling resistance characteristics can be obtained.

(oil (ii))

The modified conjugated diene polymer composition according to embodiment 1 comprises a density of more than 1.0g/cm³The oil (ii) of (a).

The modified conjugated diene polymer composition according to embodiment 2 contains a density of 1.0g/cm³The above oil (ii).

Hereinafter, the oil may be referred to as a high-density oil.

By containing the high-density oil (ii), the steering stability, rolling resistance characteristics, and wet grip performance of the modified conjugated diene polymer composition of the present embodiment are improved.

The reason why the steering stability is improved is considered to be that the inclusion of the high-density oil (ii) improves the density and rigidity of the composition as compared with the conventional modified conjugated diene polymer composition containing only the extender oil (stretching oil). From such a viewpoint, the compounding of the high-density oil results in obtaining an effect of improving both the rolling resistance property and wet grip property of the modified conjugated diene polymer composition.

The high-density oil (ii) can be used in the same manner as conventionally used extender oils to improve the processability of the modified conjugated diene polymer composition. That is, it may be added to the modified conjugated diene in the form of extender oil as requiredIn the copolymer, the amount to be added is not limited as long as the processability can be improved. The upper limit of the density of the high-density oil (ii) is preferably 1.07g/cm from the viewpoint of processability³Less than, more preferably 1.03g/cm³The following.

Examples of the high-density oil (ii) include oils derived from vegetable oils, and examples thereof include "Vivamax 5000" manufactured by H & R.

The above-mentioned high-density oil (ii) may be used in this case: the modified conjugated diene polymer (i) is added to the solution of the modified conjugated diene polymer (i) and mixed to form an oil-extended polymer solution, and then the mixture is desolventized to obtain an oil-extended polymer; it is also possible to use in this case: the modified polymer diene polymer (i) is used when it is obtained as a rubber compound by kneading it with a silica-based inorganic filler or the like in a kneader.

The conventionally used extender oil may be added to the modified conjugated diene polymer (i) or blended in the modified conjugated diene polymer composition within a range that satisfies the effects of the present invention. In this case, the total density of the high-density oil (ii) and the conventional extender oil is more than 1.0g/cm³Or the density reaches 1.0g/cm³The adjustment is performed in the above manner.

In the above adjustment, the upper limit of the total density of the high-density oil (ii) and the extender oil is preferably 1.07g/cm³Less than, more preferably 1.03g/cm³. For example, a conventionally used density of 0.95g/cm is added to 100 parts by mass of the modified conjugated diene polymer (i)³5 parts by mass of extender oil (1.02 g/cm)³30 parts by mass of the high-density oil (b) so that the total density can be adjusted to more than 1.0g/cm³And 1.03g/cm³The following.

The density of the filling oil used in the past is less than 1.0g/cm³If necessary, the modified conjugated diene polymer (i) and the rubber composition thereof are added to improve the processability (extrusion processability, etc.).

The method for adding the extender oil to the modified conjugated diene polymer (i) is not particularly limited, and the following methods are preferred: the extender oil is added to the polymer solution and mixed to form an oil-extended polymer solution which is then desolventized.

Examples of the extender oil include aromatic oil, naphthenic oil, and paraffin oil. Among these, in terms of environmental safety, prevention of oil leakage, and wet grip properties, it is preferable that the polycyclic aromatic (PCA) component measured by the IP346 method is 3 mass% or less of the substitute aromatic oil. Examples of the substitute aromatic oil include TDAE, MES, and RAE shown in Kautschuk Gummi Kunststoffe 52(12)799 (1999).

The amounts of the high-density oil (ii) and the extender oil are not particularly limited, and the total amount is usually 10 to 60 parts by mass, preferably 20 to 37.5 parts by mass, based on 100 parts by mass of the modified conjugated diene polymer (i).

As a method for obtaining the modified conjugated diene polymer (i) from the polymer solution by desolvating the oil-extended polymer solution, a known method can be used. For example, the following methods can be mentioned: a method in which the polymer is filtered out after the solvent is separated by steam stripping or the like, and is further dehydrated and dried to obtain a polymer; a method of concentrating with a flash tank and then devolatilizing with a vented extruder or the like; a method of direct devolatilization using a rotary dryer or the like.

(silica-based inorganic Filler)

The modified conjugated diene polymer composition according to embodiment 1 preferably further contains a silica-based inorganic filler.

The modified conjugated diene polymer composition according to embodiment 2 further contains a silica-based inorganic filler.

The silica-based inorganic filler may be any "silica-based inorganic filler" that is generally used to promote handling stability and the like due to the reinforcing effect of the modified conjugated diene polymer composition, and may be widely used as an essential component of the modified conjugated diene polymer composition of the present embodiment as long as it is used to obtain the strength-improving effect of the rubber composition for a base tread in particular.

The content of the silica-based inorganic filler is not limited as long as the reinforcing effect of the modified conjugated diene polymer composition of the present embodiment can be obtained, and is preferably 1 to 300 parts by mass, more preferably 5 to 150 parts by mass, and still more preferably 10 to 100 parts by mass, based on 100 parts by mass of the modified conjugated diene polymer (i).

The silica-based inorganic filler used in the modified conjugated diene polymer composition of the present embodiment is not particularly limited, and a known silica-based inorganic filler may be used, and preferably contains SiO₂Or Si₃Solid particles of Al as a structural unit, more preferably SiO₂Or Si₃Al is a main component of the structural unit.

The main component herein means a component contained in the silica-based inorganic filler by 50 mass% or more, preferably 70 mass% or more, and more preferably 80 mass% or more.

Specific examples of the silica-based inorganic filler include inorganic fibrous materials such as silica, clay, talc, mica, diatomaceous earth, wollastonite, montmorillonite, zeolite, and glass fiber. Further, a silica-based inorganic filler having a surface hydrophobized, and a mixture of a silica-based inorganic filler and an inorganic filler other than 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 the silica include dry silica, wet silica, and synthetic silicate silica. Among these, wet silica is preferable.

Examples of the dry silica include dry silica obtained by reacting purified silicon tetrachloride in a high-temperature flame, and the dry silica has a higher purity, a finer particle size, and a lower water content than the wet silica; generally, it can be widely used as a filler for silicone rubber, a thickener or a reinforcing agent for resin, a fluidizing agent for powder, or a ceramic material.

Examples of wet silica include, for example, a light white powder having a soft appearance obtained by neutralizing an aqueous solution of sodium silicate using silica sand as a raw material, precipitating silica, filtering, and drying, and the wet silica is generally used for: reinforcing fillers for synthetic rubbers; preventing powdering and solidification of a liquid such as an agricultural chemical; preventing ink penetration (pulling out け) of printing ink of light weight paper, and preventing thickening and hanging of paint and ink; a thermal insulation material; and (3) an abrasive.

In the modified conjugated diene polymer composition of the present embodiment, the nitrogen adsorption specific surface area of the silica inorganic filler determined by the BET adsorption method is preferably 100 to 300m in view of obtaining more excellent rolling resistance characteristics²(iv) g, more preferably 170 to 250m²/g。

In the modified conjugated diene polymer composition of the present embodiment, the amount of the silica inorganic filler to be mixed is preferably 1 to 300 parts by mass, more preferably 5 to 200 parts by mass, and still more preferably 20 to 150 parts by mass, per 100 parts by mass of the rubber component containing the modified conjugated diene polymer (i), from the viewpoint of the rolling resistance characteristics due to the addition of the silica inorganic filler, from the viewpoint of the steering stability, and from the viewpoint of the sufficient practical use of the extrusion processability.

(carbon Black)

The modified conjugated diene polymer composition of the present embodiment preferably further contains carbon black in relation to the rubber component containing the modified conjugated diene polymer (i), and more preferably further contains carbon black in an amount of 0.5 to 100 parts by mass in relation to 100 parts by mass of the rubber component.

The carbon black is not particularly limited, and various grades of carbon black such as SRF, FEF, HAF, ISAF, and SAF can be used. Among these, from the viewpoint of extrusion moldability and the viewpoint of rolling resistance characteristics, the nitrogen adsorption specific surface area is preferably 50m²A carbon black having a dibutyl phthalate (DBP) oil absorption of 80mL/100g or more.

The amount of carbon black to be mixed is preferably 0.5 to 100 parts by mass, more preferably 3 to 100 parts by mass, and still more preferably 5 to 50 parts by mass per 100 parts by mass of the rubber component containing the modified conjugated diene polymer, from the viewpoint of exhibiting rolling resistance characteristics due to the addition of the silica-based inorganic filler and from the viewpoint of extrusion processability.

(Metal oxide and hydroxide)

The modified conjugated diene polymer composition of the present embodiment may contain a metal oxide or a metal hydroxide in addition to the silica inorganic filler and the carbon black.

The metal oxide is represented by the chemical formula M_xO_y(M represents a metal atom, and x and y each represent an integer of 1 to 6) as the solid particles of the main component of the structural unit, and for example, alumina, titania, magnesia, zinc oxide, or the like can be used.

In addition, a mixture of a metal oxide and an inorganic filler other than the metal oxide may also be used.

The metal hydroxide is not particularly limited, and examples thereof include aluminum hydroxide, magnesium hydroxide, and zirconium hydroxide.

(silane coupling agent)

In the modified conjugated diene polymer composition of the present embodiment, a silane coupling agent is preferably added to the silica inorganic filler.

Examples of the silane coupling agent include, but are not limited to, the following: for example, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylethoxysilane, 2-mercaptoethyltrimethoxysilane, 2-mercaptoethyltriethoxysilane, ethoxy (3-mercaptopropyl) bis (3,6,9,12, 15-pentaoxadioctadecyl-1-yloxy) silane [ manufactured by Evonik Degussa: si363], NXT-Z30, NXT-Z45, NXTZ60, NXT silane and other mercapto group-containing silane coupling agents manufactured by Momentive, 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-trimethoxysilylpropyl) tetrasulfide, bis (2-trimethoxysilylethyl) tetrasulfide, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, N-mercaptopropylthiosilane, 2-mercaptoethyltrimethoxysilane, 2-mercaptoethyltriethoxysilane, 3-trimethoxysilylpropyl-N, N-dimethylthiocarbamoyl tetrasulfide, 3-triethoxysilylpropyl-N, N-dimethylthiocarbamoyl tetrasulfide, 2-triethoxysilylethyl-N, N-dimethylthiocarbamoyl tetrasulfide, 3-trimethoxysilylpropylbenzothiazolyl tetrasulfide, 3-triethoxysilylpropylbenzoyl tetrasulfide, 3-triethoxysilylmethylmethacrylate monosulfide, 3-trimethoxysilylmethylpropylmethacrylate monosulfide, bis (3-diethoxymethylsilylpropyl) tetrasulfide, bis (N-ethoxysilylpropyl) tetrasulfide, bis (N-dimethylthiocarbamoyl) sulfide, bis (N-ethylthiocarbamoyl) sulfide, 3-mercaptopropyldimethoxymethylsilane, dimethoxymethylsilylpropyl-N, N-dimethylthiocarbamoyl tetrasulfide, dimethoxymethylsilylpropylbenzothiazolyl tetrasulfide, and the like. Among them, bis- [3- (triethoxysilyl) -propyl ] -disulfide, ethoxy (3-mercaptopropyl) bis (3,6,9,12, 15-pentaoxadioctadecyl-1-yloxy) silane [ manufactured by Evonik Degussa: si363], NXT-Z30, NXT-Z45, NXTZ60, NXT silane and other mercapto group-containing silane coupling agents manufactured by Momentive and bis- [3- (triethoxysilyl) -propyl ] -tetrasulfide are preferred because of their high reinforcing effect. These silane coupling agents may be used singly or in combination of two or more.

The amount of the silane coupling agent to be mixed is preferably 0.1 to 30 parts by mass, more preferably 0.5 to 20 parts by mass, and still more preferably 1 to 15 parts by mass, per 100 parts by mass of the silica-based inorganic filler. When the amount of the silane coupling agent is within the above range, the above-mentioned addition effect by the silane coupling agent may be 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 softener for rubber, mineral oil or a liquid or low molecular weight synthetic softener is suitable.

Softening agents for mineral oil-based rubber, which are process oils or extender oils used for softening, extending and improving the processability of rubber, are mixtures of aromatic rings, naphthenic rings and paraffinic chains, softening agents in which the number of carbon atoms of a paraffinic chain is 50% or more of the total carbon atoms are called paraffinic, softening agents in which the number of carbon atoms of a naphthenic ring is 30 to 45% of the total carbon atoms are called naphthenic, and softening agents in which the number of aromatic carbon atoms is more than 30% of the total carbon atoms are called aromatic. As the softening agent for rubber used together with the modified conjugated diene-aromatic vinyl copolymer, a softening agent for rubber having an appropriate aromatic content tends to have good fusibility with the copolymer, and is therefore preferable.

The amount of the rubber softener to be mixed is preferably 0 to 100 parts by mass, more preferably 10 to 90 parts by mass, and still more preferably 30 to 90 parts by mass, per 100 parts by mass of the rubber component containing the modified conjugated diene polymer.

When the amount of the rubber softener to be mixed exceeds 100 parts by mass per 100 parts by mass of the rubber component, bleeding may easily occur and stickiness may occur on the surface of the composition.

(kneading method and other additives)

In the production of the modified conjugated diene polymer composition of the present embodiment, the method of mixing the modified conjugated diene polymer (i) with other rubbery polymer, the high-density oil (ii), and if necessary, additives such as a silica-based inorganic filler, carbon black, other fillers, a silane coupling agent, and a rubber softening agent is not particularly limited.

Examples thereof include a melt-kneading method using a usual mixer such as an open mill, a Banbury mixer, a kneader, a single-screw extruder, a twin-screw extruder, or a multi-screw extruder; and a method of dissolving and mixing the respective components and then heating to remove the solvent.

Among these, a melt kneading method using a roll, a banbury mixer, a kneader, or an extruder is preferable from the viewpoint of productivity and excellent kneading property.

Further, any of a method of kneading the modified conjugated diene polymer (i) and various compounding agents at once and a method of mixing them several times can be applied.

The modified conjugated diene polymer composition of the present embodiment can be a vulcanized rubber composition obtained by vulcanizing a non-vulcanized rubber composition with a vulcanizing agent.

As the vulcanizing agent, for example, a radical initiator such as an organic peroxide and an azo compound, an oxime compound, a nitroso compound, a polyamine compound, sulfur, and a sulfur-containing compound can be used.

The sulfur-containing compounds include sulfur monochloride, sulfur dichloride, disulfide compounds, polymer polysulfide compounds, and the like.

The vulcanizing agent is used in an amount of usually 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 containing the modified conjugated diene polymer (i). As the vulcanization method, a conventionally known method can be used, and the vulcanization temperature is usually 120 to 200 ℃ and preferably 140 to 180 ℃.

In addition, a vulcanization accelerator may be used as needed at the time of vulcanization. As the vulcanization accelerator, conventionally known materials can be used, and examples thereof include sulfenamide-based, guanidine-based, thiuram-based, aldehyde-amine-based, aldehyde-ammonia-based, thiazole-based, thiourea-based, and dithiocarbamate-based vulcanization accelerators. As the vulcanization aid, zinc white, stearic acid, or the like can be used. The vulcanization accelerator is used in an amount of usually 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 containing the modified conjugated diene polymer (i).

In the modified conjugated diene polymer composition of the present embodiment, softening agents and fillers other than those described above, and various additives such as a heat stabilizer, an antistatic agent, a weather stabilizer, an aging inhibitor, a colorant, and a lubricant may be used within a range not to impair the object of the present embodiment.

As the other softener, a known softener can be used.

Specific examples of the other fillers include calcium carbonate, magnesium carbonate, aluminum sulfate, and barium sulfate.

As the heat stabilizer, antistatic agent, weather stabilizer, aging inhibitor, colorant and lubricant, known materials can be used.

The modified conjugated diene polymer composition of the present embodiment is suitable as a composition for a base tread provided with a crosslinked product containing the modified conjugated diene polymer of the present embodiment, and is suitable for tire use as a base tread.

That is, the modified conjugated diene polymer composition of the present embodiment is used to produce a base tread, and the base tread is bonded to other members and heated and pressurized by a tire building machine, whereby a tire can be produced.

By using the modified conjugated diene polymer composition of the present embodiment, a tire having an excellent balance between rolling resistance characteristics and steering stability can be produced.

Examples

The present embodiment will be described in more detail below by way of specific examples and comparative examples, but the present embodiment is not limited to the following examples.

In the examples and comparative examples, the structure and physical properties of the polymer were measured by the following methods.

(Property 1) amount of bonded styrene

The modified conjugated diene polymer was used as a sample, and 100mg of the sample was dissolved in chloroform to a constant volume of 100mL to prepare a measurement sample.

The amount (mass%) of bound styrene based on 100 mass% of the modified conjugated diene polymer as a sample was measured from the amount of styrene absorbed by phenyl groups at an ultraviolet absorption wavelength (around 254 nm) (spectrophotometer "UV-2450" manufactured by Shimadzu corporation).

(Property 2) microstructure of butadiene portion (1, 2-vinyl bond amount)

The modified conjugated diene polymer was used as a sample, and 50mg of the sample was dissolved in 10mL of carbon disulfide to prepare a measurement sample.

Using a solution pool at 600-1000 cm^-1The infrared spectrum was measured, and the microstructure of the butadiene portion, that is, the 1, 2-vinyl bond content (mol%) was determined from the absorbance at a predetermined wave number according to the calculation formula of the Hampton method (the method described in r.r. Hampton, Analytical Chemistry 21,923(1949)) (fourier transform infrared spectrophotometer "FT-IR 230" manufactured by japan spectrophotometer).

(Property 3) molecular weight

Using a GPC measurement apparatus in which 3 columns each containing a polystyrene gel as a filler were connected to each other, the chromatogram was measured using the modified conjugated diene polymer as a sample, and the weight average molecular weight (Mw) and the number average molecular weight (Mn) were determined based on a calibration curve using standard polystyrene.

The eluent was 5mmol/L THF mixed with triethylamine. As the column, those available from Tosoh under the trade name "TSKguardcolumn SuperH-H", and those available from Tosoh under the trade name "TSKgel SuperH 5000", "TSKgel SuperH 6000", and "TSKgel SuperH 7000", were used as the guard column.

An RI detector (trade name "HLC 8020" manufactured by Tosoh corporation) was used under conditions of an oven temperature of 40 ℃ and a THF flow rate of 0.6 mL/min.

10mg of a sample for measurement was dissolved in 20mL of THF to prepare a measurement solution, and 20. mu.L of the measurement solution was injected into a GPC measurement apparatus and measured.

(Property 4) Mooney viscosity

The Mooney viscosity was measured using an L-rotor in accordance with JIS K6300 using a Mooney viscometer (trade name "VR 1132" manufactured by Shanghai Co., Ltd.) using the modified conjugated diene polymer as a sample.

The measurement temperature was 110 ℃ when the conjugated diene polymer was used as a sample, and 100 ℃ when the modified conjugated diene polymer was used as a sample.

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

(Property 5) modification ratio

The modified conjugated diene polymer was used as a sample, and the measurement was performed by using the property that the modified basic polymer component was adsorbed on a GPC column using a silica gel as a filler. The modification rate of a sample solution containing a sample and low-molecular-weight internal standard polystyrene was determined by measuring the adsorption amount on a silica-based column from the difference between a chromatogram measured with a polystyrene-based column and a chromatogram measured with a silica-based column. The details are as follows.

The results of the measurements using the following measurement conditions are shown in tables 1 to 2 below.

Preparation of sample solution: a sample solution was prepared by dissolving 10mg of the sample and 5mg of standard polystyrene in 20mL of THF.

Measurement conditions: a sample solution (20. mu.L) was injected into the apparatus using 5mmol/L of THF mixed with triethylamine as an eluent, and the measurement was carried out. As the column, those available from Tosoh under the trade name "TSKguardcolumn SuperH-H", and those available from Tosoh under the trade name "TSKgel SuperH 5000", "TSKgel SuperH 6000", and "TSKgel SuperH 7000", were used as the guard column. The measurement was performed using an RI detector (HLC 8020, manufactured by Tosoh corporation) under conditions of a column box temperature of 40 ℃ and a THF flow rate of 0.6 mL/min, and a chromatogram was obtained.

GPC measurement conditions using silica-based column: a sample solution (50. mu.L) was poured into the apparatus using "HLC-8320 GPC" manufactured by Tosoh corporation and THF as an eluent, and a chromatogram was obtained using an RI detector under conditions of a column box temperature of 40 ℃ and a THF flow rate of 0.5 ml/min. As the analytical column, trade names "Zorbax PSM-1000S", "PSM-300S" and "PSM-60S" were used in series, and as the preceding protective column, trade name "DIOL 4.6X 12.5mm 5 micron" was used in series.

The calculation method of the modification rate comprises the following steps: the modification ratio (%) was determined by the following formula, with the peak area of the chromatogram using a polystyrene column taken as a whole to be 100, the peak area of the sample taken as P1, the peak area of the standard polystyrene taken as P2, the peak area of the chromatogram using a silica column taken as a whole to be 100, the peak area of the sample taken as P3, and the peak area of the standard polystyrene taken as P4.

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

(wherein, P1+ P2 ═ P3+ P4 ═ 100)

(Property 6) handling stability

The viscoelastic parameters were measured in a torsional mode using a viscoelasticity tester (ARES-G2) manufactured by TA INSTRUMENTS.

Each measured value is indexed with the values of comparative examples 1 to 10 and 12 to 17 being 100 in each table.

The storage modulus G' measured at 50 ℃, frequency 10Hz, and strain 3% was used as an index of steering stability. A larger value indicates better steering stability.

(Property 7) Rolling resistance characteristics

Tan measured at 50 ℃, frequency 10Hz, and strain 3% was used as an index of rolling resistance characteristics (fuel economy). Smaller values indicate better rolling resistance characteristics.

(Property 8) Wet grip Property

Tan measured at 0 ℃, frequency 10Hz, strain 1% is an index of rolling resistance characteristics (fuel economy). Larger values indicate better rolling resistance characteristics.

The composition of a commercially available oil-extended modified conjugated diene polymer was determined by separating oil by the following oil extraction method.

The density of the oil extracted by this method is measured to compare with the modified conjugated diene polymer of the present embodiment.

< oil extraction method >

As a method for extracting oil from the oil-extended modified conjugated diene polymer, a soxhlet extraction method (acetone) is employed.

The oil contained in the oil-extended modified conjugated diene polymer is dissolved and extracted with acetone, and thereafter the acetone is evaporated to separate the residual oil.

Using a device called a Soxhlet extractor having a heater and a container to which a solvent is added at the lowermost part, a cylinder containing a filter paper (containing a sample of an oil-extended conjugated diene polymer) at the middle, and a cooling tube at the uppermost part; the oil is extracted from the oil-extended modified conjugated diene polymer by a soxhlet extraction method (acetone) using acetone.

When the solvent container was heated, acetone was evaporated, and the mixture was cooled by the uppermost cooling tube, dropped into the oil-extended modified conjugated diene polymer, and the solvent-soluble component was dissolved in a small amount and returned to the solvent container. Since the boiling point of the solvent-soluble component is higher than that of the solvent, the solvent-soluble component is gradually concentrated in the solvent container by repeating this cycle, and the solvent-insoluble component remains in the filter paper. The refluxed solvent is not saturated because it does not contain the target component, and extraction is performed efficiently with a smaller amount of solvent.

More than 99% of the oil can be extracted by Soxhlet extraction (acetone), and the oil extracted by Soxhlet extraction is heated several times during the addition of acetone, evaporation of acetone, purification, and deodorization, but the temperature is not increased to a high temperature (more than 100 ℃) during Soxhlet extraction in order to avoid changes in the state of the oil.

Production example 1-1

A temperature-controlled autoclave having an internal volume of 10L and equipped with a stirrer and a jacket was used as a reactor, 777g of 1, 3-butadiene, 273g of styrene, 4800g of cyclohexane from which impurities had been removed in advance, and 0.81g of 2, 2-bis (2-tetrahydrofuryl) propane as a polar substance were charged into the reactor, and the internal temperature of the reactor was maintained at 42 ℃.

A cyclohexane solution containing 9.5mmol of n-butyllithium as a polymerization initiator was supplied to the reactor.

After the polymerization reaction started, the temperature in the reactor started to rise by the heat generated by the polymerization, and the temperature in the reactor finally reached 73 ℃. After 2 minutes had reached the peak of the reaction temperature, 4.3mmol of tetraglycidyl-1, 3-bisaminomethylcyclohexane was added to the reactor, and the mixture was stirred at 72 ℃ for 2 minutes to carry out a modification reaction, 30g (30 parts by mass) of a high-density oil (Vivamax 5000, trade name) manufactured by H & R was added to 100g of the polymer, and the mixture was mixed by a mixer, and after 2.1g of an antioxidant (BHT) was added to the polymerization solution, the solvent was removed by stripping, and the polymer was dried by a dryer, thereby obtaining a modified conjugated diene polymer having a branched molecular structure in which a nitrogen-containing epoxy group substituent was used as a branching origin (sample. alpha.1).

Production examples 1 and 2

In production example 1-1, 7g (7 parts by mass) of a high-density oil having a trade name of "Vivamax 5000" manufactured by H & R was added to 100g of the polymer instead of the high-density oil having a trade name of "Vivamax 5100" manufactured by H & R. Other conditions were carried out in the same manner as in production example 1-1 to obtain a modified conjugated diene polymer (sample. alpha.2).

Production examples 1 to 3

In production example 1-1, 30g (30 parts by mass) of extender oil having a trade name of "Vivamax 5000" manufactured by H & R was added to 100g of the polymer, instead of high-density oil having a trade name of "Vivamax 5000" manufactured by H & R. Other conditions were carried out in the same manner as in production example 1-1 to obtain a modified conjugated diene polymer (sample. alpha.3).

Production examples 1 to 4

In production example 1-1, 7g (7 parts by mass) of extender oil having a trade name of "Vivamax 5000" manufactured by H & R was added to 100g of the polymer, instead of high-density oil having a trade name of "Vivamax 5000" manufactured by H & R. Other conditions were carried out in the same manner as in production example 1-1 to obtain a modified conjugated diene polymer (sample. alpha.4).

Production examples 1 to 5

In production example 1-1, 30g (30 parts by mass) of extender oil having a trade name of "Nytex 4700" manufactured by Ninas was added to 100g of the polymer, instead of high-density oil having a trade name of "Vivamax 5000" manufactured by H & R. Other conditions were carried out in the same manner as in production example 1-1 to obtain a modified conjugated diene polymer (sample. alpha.5).

Production examples 1 to 6

In production example 1-1, 7g (7 parts by mass) of modified silicone oil having a trade name of "SH 510" manufactured by Toray Dow Corning was added to 100g of the polymer, without adding a high-density oil having a trade name of "Vivamax 5000" manufactured by H & R. Other conditions were carried out in the same manner as in production example 1-1 to obtain a modified conjugated diene polymer (sample. alpha.6).

Production examples 1 to 7

In production example 1-1, a high-density oil having a trade name of "Vivamax 5000" manufactured by H & R was not added. Other conditions were carried out in the same manner as in production example 1-1 to obtain a modified conjugated diene polymer (sample. alpha.7).

Production example 2-1

An autoclave having an internal volume of 10L and a stirrer and a jacket was used as a reactor, cyclohexane and n-butyllithium were added to the reactor, the mixture was washed, then replaced with nitrogen, 4583g of cyclohexane, 47.4g of divinylbenzene and 500g of 1, 3-butadiene were added thereto, the temperature in the reactor was maintained at 40 ℃, then 341g of an n-butyllithium solution was added thereto, the reaction was carried out for 90 minutes, and the temperature in the reactor was raised to 80 ℃. Thereafter, the inside of the reactor was naturally cooled for 2 hours to prepare a multifunctional catalyst.

The n-butyllithium solution of the above raw material was a solution having a weight mixing ratio of n-butyllithium/cyclohexane of 20/80. The divinylbenzene includes m-divinylbenzene, p-divinylbenzene, ethylbenzene, and the like, and a divinylbenzene mixture (manufactured by Nissian iron chemical) having a divinylbenzene concentration of 57 mass% is used.

An autoclave having an internal volume of 40L and a stirrer and a jacket was used as a reactor, cyclohexane and n-butyllithium were added to the reactor, followed by purging, nitrogen substitution was performed, 20915g of cyclohexane, 779g of styrene, 4.5g of 2, 2-bis (2-tetrahydrofuryl) propane as a polar compound, and 2221g of butadiene were added to the reactor, the temperature in the reactor was maintained at 45 ℃, 204g of a polyfunctional anionic initiator was added to start a polymerization reaction, and then the polymerization reaction reached a peak temperature in the reactor of 83 ℃ and was terminated. 1 minute after the completion of the polymerization reaction, 5.6g of 1- [3- (triethoxysilyl) propyl ] -4-methylpiperazine as a modifier was fed into the reactor at an addition rate of not more than 5 seconds, and a modification reaction was carried out for 10 minutes, 10g (10 parts by mass) of a high-density oil having a trade name "Vivamax 5000" manufactured by H & R was added to 100g of the polymer, and the mixture was mixed by a mixer, and then the solvent was removed by stripping, followed by vacuum drying, whereby a modified conjugated diene polymer having a branched molecular structure with a nitrogen-containing alkoxysilane substituent as a branching origin was obtained (sample. beta.1). As the n-butyllithium solution, a solution having a weight mixing ratio of n-butyllithium/cyclohexane of 20/80 was used.

Production example 2-2

A modified conjugated diene polymer (sample. beta.2) was obtained in the same manner as in production example 2-1, except that 10g (10 parts by mass) of extender oil having a trade name of "Vivatec 500" manufactured by H & R was added to 100g of the polymer instead of the high-density oil having a trade name of "Vivamax 5000" manufactured by H & R.

Production example 3-1

A temperature-controllable autoclave having an internal volume of 5L and equipped with a stirrer and a jacket was used as a reactor, 265g of 1, 3-butadiene, 93g of styrene, 2030g of cyclohexane, and 3.8mmol of 2, 2-bis (2-tetrahydrofuryl) propane as a polar material from which impurities had been removed in advance were charged into the reactor, and the internal temperature of the reactor was maintained at 50 ℃. A cyclohexane solution of 1-lithiumpiperidine (5.10mmol) (the 1-lithiumpiperidine is obtained by reacting piperidine (5.10mmol) and n-butyllithium (5.10 mmol)) as a polymerization initiator was supplied to the reactor. After the polymerization reaction started, the temperature in the reactor started to rise by the heat generated by the polymerization, and finally the temperature in the reactor reached 78 ℃.

After 2 minutes had reached the peak of the reaction temperature, 0.587mmol of tris (3-trimethoxysilylpropyl) amine was added to the reactor to conduct a modification reaction for 5 minutes, 30g (30 parts by mass) of a high-density oil having a trade name of "Vivamax 5000" manufactured by H & R was added to 100g of the polymer, the mixture was mixed by a mixer, 1.0g of an antioxidant (2, 6-di-tert-butyl-4-hydroxytoluene; BHT) was added thereto, the solvent was removed by stripping, and the modified conjugated diene polymer having a branched molecular structure with a nitrogen-containing alkoxysilane substituent as a branching origin was obtained by drying treatment using a dryer (sample γ 1).

Production example 3-2

Production example 3-1 was conducted by adding 30g (30 parts by mass) of extender oil having a trade name of "Vivatec 500" manufactured by H & R to 100g of the polymer, without adding high-density oil having a trade name of "Vivamax 5000" manufactured by H & R. Other conditions were carried out in the same manner as in production example 3-1 to obtain a modified conjugated diene polymer (sample γ 2).

Production example 4-1

A temperature-controlled autoclave having an internal volume of 5L (L/D:3.4) and equipped with a stirrer and a jacket was used as a reactor, 1995g of n-hexane and n-butyllithium as impurities which might inhibit the polymerization reaction and were present in the reactor were charged into the reactor, and the reactor was stirred at 70 ℃ for 5 minutes, then cooled to room temperature, the solution was taken out, and the reactor was emptied.

Subsequently, 1670g of n-hexane from which impurities had been removed in advance, 83g of styrene, 236g of 1, 3-butadiene, and 3.50mmol of 2, 2-bis (2-tetrahydrofuryl) propane as a polar substance were charged into a reactor, and 3.59mmol of n-butyllithium as a polymerization initiator was added to the reactor at 50 ℃ to start polymerization.

Immediately after the start of polymerization, the temperature in the reactor rose to meet the peak temperature, which was 81 ℃. After confirming that the temperature decreased, 0.38mmol of tetrakis (3-trimethoxysilylpropyl) -1, 3-propanediamine adjusted to 50 ℃ was added as a coupling agent, and the mixture was further stirred for 10 minutes. The stirring speed at this time was 200 rpm. The coupling agent was added 2 minutes after the peak temperature was reached.

2.92mmol of ethanol as a polymerization terminator was added thereto to stop the reaction, thereby obtaining a polymer solution containing the modified conjugated diene polymer.

To the resulting polymerization solution were added 0.64g of 2, 6-di-tert-butyl-4-hydroxytoluene as an antioxidant, 25.7g (25.7 parts by mass) of a high-density oil having a trade name of "Vivamax 5000" manufactured by H & R and 4.3g (4.3 parts by mass) of a extender oil having a trade name of "Vivatec 500" manufactured by H & R to 100g of the polymer, and the mixture was mixed by a mixer, followed by stripping to remove the solvent and vacuum drying to obtain a modified conjugated diene copolymer having a branched molecular structure in which a nitrogen-containing alkoxysilane substituent was a branching origin (sample θ 1).

Production example 4-2

In production example 4-1, 30g (30 parts by mass) of a high-density oil having a trade name of "Vivamax 5000" manufactured by H & R was added instead of extender oil having a trade name of "Vivatec 500" manufactured by H & R. Other conditions were carried out in the same manner as in production example 4-1 to obtain a modified conjugated diene polymer (sample. theta.2).

Production examples 4 to 3

In production example 4-2, 7g (7 parts by mass) of a high-density oil having a trade name of "Vivamax 5100" manufactured by H & R was added instead of the high-density oil having a trade name of "Vivamax 5000" manufactured by H & R. Other conditions were carried out in the same manner as in production example 4-2 to obtain a modified conjugated diene polymer (sample θ 3).

Production examples 4 to 4

In production example 4-1, 30g (30 parts by mass) of extender oil having a trade name of "Vivatec 500" manufactured by H & R was added instead of the high-density oil having a trade name of "Vivamax 5000" manufactured by H & R. Other conditions were carried out in the same manner as in production example 4-1 to obtain a modified conjugated diene polymer (sample. theta.4).

Production examples 4 to 5

In production example 4-2, 7g (7 parts by mass) of extender oil having a trade name of "Vivatec 500" manufactured by H & R was added instead of the high-density oil having a trade name of "Vivamax 5000" manufactured by H & R. Other conditions were carried out in the same manner as in production example 4-2 to obtain a modified conjugated diene polymer (sample. theta.5).

Production examples 4 to 6

In production example 4-4, extender oil having a trade name of "Vivatec 500" manufactured by H & R was added in an amount of 4.3g (4.3 parts by mass). Other conditions were carried out in the same manner as in production example 4-4 to obtain a modified conjugated diene polymer (sample θ 6).

Production example 5-1

In production example 1-1, the amount of tetraglycidyl-1, 3-bisaminomethylcyclohexane added was 1.46 mmol. Other conditions were carried out in the same manner as in production example 1-1 to obtain a modified conjugated diene polymer (sample 1).

Production example 5-2

In production example 5-1, 30g (30 parts by mass) of extender oil having a trade name of "Vivatec 500" manufactured by H & R was added instead of the high-density oil having a trade name of "Vivamax 5000" manufactured by H & R. Other conditions were carried out in the same manner as in production example 5-1 to obtain a modified conjugated diene polymer (sample 2).

Production example 6-1

In production example 1-1, the amount of tetraglycidyl-1, 3-bisaminomethylcyclohexane added was 3.25 mmol. Other conditions were carried out in the same manner as in production example 1-1 to obtain a modified conjugated diene polymer (sample. sigma.1).

Production example 6-2

In production example 6-1, 30g (30 parts by mass) of extender oil having a trade name of "Vivatec 500" manufactured by H & R was added instead of the high-density oil having a trade name of "Vivamax 5000" manufactured by H & R. Other conditions were carried out in the same manner as in production example 6-1 to obtain a modified conjugated diene polymer (sample. sigma.2).

Production examples 6 to 3

Extender oil under the trade name "Vivatec 500" manufactured by H & R Co., Ltd was not added to production example 6-2. Other conditions were carried out in the same manner as in production example 6-2 to obtain a modified conjugated diene polymer (sample. sigma.3).

The production conditions, the bonded styrene amount, the 1, 2-vinyl bonding amount, the Mooney viscosity, the modification ratio, the weight average molecular weight (Mw), the number average molecular weight (Mn), and the Mw/Mn ratio of the modified conjugated diene polymers produced in production examples 1-1 to 6-3 are shown in tables 1 and 2.

Examples 1 to 17 and comparative examples 1 to 17

An unvulcanized rubber composition and a vulcanized rubber composition were produced by kneading the following materials by the following methods.

Modified conjugated diene polymer: samples α 1 to α 6, β 1, β 2, γ 1, γ 2, θ 1 to θ 6, 1,2, and σ 1 to σ 3 (modified conjugated diene polymers produced in production examples 1-1 to 6-3)

Silica (Evonik Japan, Inc.; Ultrasil 7000GR, nitrogen adsorption specific surface area 175 m)²/g)

Silane coupling agent (Evonik Japan, Si75)

High density oil 1 (H)&Vivamax5000, manufactured by R, density 1.02g/cm³)

High density oil 2 (H)&Vivamax5100, manufactured by R, having a density of 1.01g/cm³)

Extender oil 1 (H)&Manufactured by R, Vivatec500, density 0.95g/cm³)

Modified Silicone oil (manufactured by Toray Dow Corning, Ltd.), phenyl-modified Dimethicone, SH510, Density 0.99g/cm³)

Extender oil 2 (Nytex 4700, manufactured by Ninas Co., Ltd., density 0.94 g/cm)³)

Carbon Black (Seast KH (N339), manufactured by Toshiba carbon Co., Ltd.)

Adhesive resin 1 (hydrogenated cyclopentadiene "DCPD" manufactured by UNS chemical Co., Ltd.)

Adhesive resin 2 (modified terpene phenol resin "T160" manufactured by Yasuhara Chemical Co., Ltd.)

Zinc white (manufactured by Mitsui Metal mining, Ltd., Zinc white No. 1)

Stearic acid

Wax: (Sunnoc, manufactured by Dainixing chemical industry Co., Ltd.)

Anti-aging agent (N-isopropyl-N' -phenyl-p-phenylenediamine)

Sulfur, sulfur

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

Vulcanization accelerator 2 (diphenylguanidine)

[ example 1]

Unvulcanized rubber compositions and vulcanized rubber sheets were obtained by kneading in the following manner according to the compounding ratios shown in Table 3.

Kneading was carried out for 4 minutes using a kneader (internal volume 0.5L) equipped with a temperature control device under conditions of a filling rate of 65% and a rotor rotation speed of 50rpm, using the modified conjugated diene polymer (sample. alpha.1), silica and a silane coupling agent, as first-stage kneading. At the moment, the discharge temperature is adjusted to 155-160 ℃ through the temperature control of the kneader, and the mixture is obtained. The bulk density of the blend oil (a general term for the high-density oil, the extender oil and the modified silicone oil) used in this case was 1.02g/cm³。

Subsequently, as a second kneading, the compound obtained above was cooled to room temperature, and then carbon black, zinc white, stearic acid, wax and an antioxidant were added thereto, and the mixture was kneaded for 3.5 minutes by the kneader. In this case, the discharge temperature is also adjusted to 155 to 160 ℃ by controlling the temperature of the kneader. The discharge temperature is controlled by measuring the temperature of each compound discharged from the kneader after kneading.

Further, after the obtained compound was cooled to room temperature, the unvulcanized rubber composition was heated at 70 ℃ for 30 minutes by using an oven, and then plasticated as a third kneading stage by a kneader set at 70 ℃ for 30 seconds, then kneaded for 1.5 minutes by adding sulfur and a vulcanization accelerator, and discharged at 105 ℃ to obtain an unvulcanized rubber composition.

Thereafter, the unvulcanized rubber composition was vulcanized and molded by a press vulcanizer at 160 ℃ for 20 minutes to obtain a vulcanized rubber sheet. The vulcanized rubber sheets were evaluated for rolling resistance characteristics, handling stability, and wet grip.

[ example 2]

As the modified conjugated diene polymer, 110 parts by mass of "sample β 2" produced in production example 2-1 was used instead of "sample α 1" produced in production example 1-1. The sample β 2 contained 10 parts by mass of the high-density oil 1. The rolling resistance characteristics, steering stability, and wet grip performance were evaluated in the same manner as in example 1, except that 20 parts by mass of the high-density oil 1 was blended so that the amount of the blended oil including the high-density oil in the sample β 2 reached 30 parts by mass.

The density of the whole mixed oil used at this time was 1.02g/cm³。

[ example 3]

The rolling resistance characteristics, steering stability and wet grip performance were evaluated in the same manner as in example 1, except that "sample α 1" produced in production example 1-1 and "sample γ 1" produced in production example 3-1 were used as the modified conjugated diene polymer. The sample γ 1 contained 30 parts by mass of the high-density oil 1.

The density of the whole mixed oil used at this time was 1.02g/cm³。

[ example 4]

The rolling resistance characteristics, steering stability and wet grip performance were evaluated in the same manner as in example 1, except that "sample α 1" produced in production example 1-1 was not used, but "sample θ 1" produced in production example 4-1 was used as the modified conjugated diene polymer. Sample γ 1 contained 25.7 parts by mass of high-density oil 1 and 4.3 parts by mass of extender oil, the total being 30 parts by mass.

The density of the whole mixed oil used at this time was 1.01g/cm³。

[ example 5]

The rolling resistance characteristics, steering stability and wet grip performance were evaluated by performing the same operations as in example 1, except that 107 parts by mass of the "sample α 2" prepared in production example 1-2, instead of the "sample α 1" prepared in production example 1-1, were used, the silica content was changed to 20 parts by mass, and the silane coupling agent content was changed to 1.6 parts by mass, and no carbon black was added. The sample α 2 contained 7 parts by mass of the extender oil 2.

The density of the whole mixed oil used at this time was 1.01g/cm³。

[ example 6]

In example 1, the rolling resistance characteristic, steering stability and wet grip performance were evaluated by performing the same operations as in example 1 except that 40 parts by mass of the high-density oil 1 was compounded so that the amount of the internal oil including the high-density oil component in the sample α 1 reached 70 parts by mass, the silica content was changed to 200 parts by mass, and the silane coupling agent content was changed to 16 parts by mass, and no carbon black was compounded.

The density of the whole mixed oil used at this time was 1.02g/cm³。

[ example 7]

The rolling resistance characteristics, steering stability and wet grip performance were evaluated in the same manner as in example 1, except that 130 parts by mass of the "sample θ 2" prepared in production example 2-2 was used instead of the "sample α 1" prepared in production example 1-1 in example 1. The sample θ 2 contained 30 parts by mass of the extender oil 1.

The density of the whole mixed oil used at this time was 1.02g/cm³。

[ example 8]

In example 1, the same operations as in example 1 were carried out to evaluate the rolling resistance characteristics, steering stability and wet grip performance, except that 107 parts by mass of the "sample θ 3" produced in production example 4-3, instead of the "sample α 1" produced in production example 1-1, were used, the mixing amount of silica was changed to 20 parts by mass, and the mixing amount of silane coupling agent was changed to 1.6 parts by mass, and carbon black was not blended. The sample θ 3 contained 7 parts by mass of the extender oil 2.

The density of the whole mixed oil used at this time was 1.01g/cm³。

[ example 9]

In example 7, the rolling resistance characteristic, steering stability and wet grip performance were evaluated by performing the same operations as in example 7 except that 40 parts by mass of the high-density oil 1 was compounded so that the amount of the internal oil including the high-density oil in the sample θ 2 reached 70 parts by mass, the silica mixing amount was changed to 200 parts by mass, and the silane coupling agent mixing amount was changed to 16 parts by mass, and no carbon black was compounded.

The density of the whole mixed oil used at this time was 1.02g/cm³。

[ example 10]

The rolling resistance characteristics, steering stability and wet grip performance were evaluated in the same manner as in example 1, except that 130 parts by mass of "sample 1" produced in production example 5-1 was used instead of "sample α 1" produced in production example 1-1 in example 1. Sample 1 contained 30 parts by mass of extender oil 1.

The density of the whole mixed oil used at this time was 1.02g/cm³。

[ example 11]

The rolling resistance characteristics, steering stability and wet grip performance were evaluated in the same manner as in example 1, except that 130 parts by mass of the "sample σ 1" prepared in production example 6-1 was used instead of the "sample α 1" prepared in production example 1-1 in example 1. The sample σ 1 contained 30 parts by mass of the extender oil 1.

The density of the whole mixed oil used at this time was 1.02g/cm³。

[ example 12]

Rolling resistance characteristics, steering stability, and wet grip performance were evaluated in the same manner as in example 1, except that 2 parts by mass of adhesive resin 1 (hydrogenated cyclopentadiene "DCPD" manufactured by UNS Chemical) and 3 parts by mass of adhesive resin 2 (modified terpene phenol resin "T160" manufactured by Yasuhara Chemical) were used in example 1.

The density of the whole mixed oil used at this time was 1.02g/cm³。

[ example 13]

In example 1, rolling resistance characteristics, steering stability, and wet grip performance were evaluated by performing the same operations as in example 1 except that 100 parts by mass of "sample σ 3" produced in production example 6-3 was used instead of "sample α 1" produced in production example 1-1 in example 1, 40 parts by mass of the high-density oil 1 was blended, the silica mixing amount was changed to 100 parts by mass, and the silane coupling agent mixing amount was changed to 8 parts by mass.

The density of the whole mixed oil used at this time was 1.02g/cm³。

[ example 14]

The rolling resistance characteristics, steering stability, and wet grip performance were evaluated in the same manner as in example 1, except that 100 parts by mass of the "sample α 7" produced in production examples 1 to 7 was used instead of the "sample α 1" produced in production examples 1 to 1, and that 30 parts by mass of the high-density oil 1 was blended.

The density of the whole mixed oil used at this time was 1.02g/cm³。

[ example 15]

The rolling resistance characteristics, steering stability, and wet grip performance were evaluated in the same manner as in example 1, except that 104.3 parts by mass of the "sample θ 6" produced in production example 4-6 was used instead of the "sample α 1" produced in production example 1-1, and that 25.7 parts by mass of the high-density oil 1 was blended so that the amount of the internal oil mixture including the components of the extender oil 1 in the sample θ 6 became 30 parts by mass.

The density of the whole mixed oil used at this time was 1.02g/cm³。

[ example 16]

In example 14, rolling resistance characteristics, steering stability, and wet grip performance were evaluated in the same manner as in example 1, except that the high-density oil 1 was not used, the amount of the high-density oil 2 was changed to 7 parts by mass, the amount of the silica was changed to 20 parts by mass, and the amount of the silane coupling agent was changed to 1.6 parts by mass, and carbon black, zinc white, stearic acid, wax, and an antioxidant were not added.

The density of the whole mixed oil used at this time was 1.01g/cm³。

[ example 17]

In example 14, rolling resistance characteristics, steering stability, and wet grip performance were evaluated in the same manner as in example 1, except that the amount of the high-density oil 1 was changed to 70 parts by mass, the amount of the silica was changed to 200 parts by mass, and the amount of the silane coupling agent was changed to 16 parts by mass, and carbon black, zinc white, stearic acid, wax, and an antioxidant were not added.

The density of the whole mixed oil used at this time was 1.02g/cm³。

Comparative example 1

The rolling resistance characteristics, steering stability and wet grip performance were evaluated in the same manner as in example 1, except that 130 parts by mass of the "sample α 3" prepared in production example 1-3 was used instead of the "sample α 1" prepared in production example 1-1 in example 1. The sample α 3 contained 30 parts by mass of the extender oil 1.

The density of the whole mixed oil used at this time was 0.95g/cm³。

Comparative example 2

In example 2, rolling resistance characteristics, steering stability, and wet grip performance were evaluated in the same manner as in example 2 except that 110 parts by mass of the "sample β 2" prepared in production example 2-2 was used as the modified conjugated diene polymer instead of the "sample β 1" prepared in production example 2-1. The sample β 2 contained 10 parts by mass of the extender oil 1.

The density of the whole mixed oil used at this time was 0.95g/cm³。

Comparative example 3

In example 3, rolling resistance characteristics, steering stability, and wet grip performance were evaluated in the same manner as in example 3 except that 130 parts by mass of the "sample γ 2" prepared in production example 2-2 was used instead of the "sample γ 1" prepared in production example 3-1 as the modified conjugated diene polymer. The sample γ 2 contained 30 parts by mass of extender oil 1.

The density of the whole mixed oil used at this time was 0.95g/cm³。

Comparative example 4

In example 7, rolling resistance characteristics, steering stability, and wet grip performance were evaluated in the same manner as in example 3, except that 130 parts by mass of the "sample θ 4" produced in production example 4-4 was used instead of the "sample θ 2" produced in production example 4-2 as the modified conjugated diene polymer. The sample θ 4 contained 30 parts by mass of the extender oil 1.

The density of the whole mixed oil used at this time was 0.95g/cm³。

Comparative example 5

In example 5, rolling resistance characteristics, steering stability, and wet grip performance were evaluated in the same manner as in example 5 except that 107 parts by mass of the "sample α 4" produced in production examples 1 to 4 was used instead of the "sample α 2" produced in production examples 1 to 2 as the modified conjugated diene polymer. The sample α 4 contained 7 parts by mass of the extender oil 1.

The density of the whole mixed oil used at this time was 0.95g/cm³。

Comparative example 6

In comparative example 1, rolling resistance characteristics, steering stability, and wet grip were evaluated in the same manner as in comparative example 1 except that 40 parts by mass of extender oil 1 was blended so that the amount of the extender oil including the extender oil in sample α 3 reached 70 parts by mass, the silica blending amount was changed to 200 parts by mass, and the silane coupling agent blending amount was changed to 16 parts by mass, and carbon black was not blended.

The density of the whole mixed oil used at this time was 0.95g/cm³。

Comparative example 7

In example 8, rolling resistance characteristics, steering stability, and wet grip performance were evaluated in the same manner as in example 8 except that 107 parts by mass of the "sample θ 5" produced in production example 4-5 was used instead of the "sample θ 3" produced in production example 4-3 as the modified conjugated diene polymer. The sample θ 5 contained 7 parts by mass of the extender oil 1.

The density of the whole mixed oil used at this time was 0.95g/cm³。

Comparative example 8

In comparative example 4, rolling resistance characteristics, steering stability, and wet grip were evaluated in the same manner as in comparative example 4 except that 40 parts by mass of extender oil 1 was blended so that the amount of the extender oil including the filler oil in sample θ 4 reached 70 parts by mass, the silica blending amount was changed to 200 parts by mass, and the silane coupling agent blending amount was changed to 16 parts by mass, and carbon black was not blended.

The density of the whole mixed oil used at this time was 0.95g/cm³。

Comparative example 9

In example 10, rolling resistance characteristics, steering stability, and wet grip performance were evaluated in the same manner as in example 10 except that 130 parts by mass of "sample 2" produced in production example 5-2 was used instead of "sample 1" produced in production example 5-1 as the modified conjugated diene polymer. Sample 2 contained 30 parts by mass of extender oil 1.

The density of the whole mixed oil used at this time was 0.95g/cm³。

Comparative example 10

In example 11, rolling resistance characteristics, steering stability, and wet grip performance were evaluated in the same manner as in example 11 except that 130 parts by mass of the "sample σ 2" prepared in production example 6-2 was used instead of the "sample σ 1" prepared in production example 6-1 as the modified conjugated diene polymer. The sample σ 2 contained 30 parts by mass of the extender oil 1.

The density of the whole mixed oil used at this time was 0.95g/cm³。

Comparative example 11

In example 5, rolling resistance characteristics, steering stability, and wet grip performance were evaluated in the same manner as in example 5 except that 7 parts by mass of the "sample α 6" produced in production examples 1 to 6 was used instead of the "sample α 2" produced in production examples 1 to 2 as the modified conjugated diene polymer. The sample α 6 contained 7 parts by mass of a modified silicone oil (phenyl-modified dimethylsilicone oil manufactured by Toray Dow Corning, SH 510).

The density of the whole mixed oil used at this time was 0.99g/cm³。

Comparative example 12

The rolling resistance characteristics, steering stability and wet grip performance were evaluated in the same manner as in example 1, except that 30 parts by mass of the "sample α 5" prepared in production examples 1 to 5 was used as the modified conjugated diene polymer in example 1 instead of the "sample α 1" prepared in production examples 1 to 1. Sample α 5 contained extender oil 2 (Nytex 4700, manufactured by Ninas, density 0.94 g/cm)³) Is 30 parts by mass.

The density of the whole mixed oil used at this time was 0.94g/cm³。

Comparative example 13

In example 13, rolling resistance characteristics, steering stability, and wet grip performance were evaluated in the same manner as in example 13 except that 40 parts by mass of extender oil 1 was added instead of using the high-density oil 1.

Comparative example 14

The rolling resistance characteristics, steering stability, and wet grip performance were evaluated in the same manner as in example 14, except that 30 parts by mass of extender oil 1 was added instead of using the high-density oil 1 in example 14.

The density of the whole mixed oil used at this time was 0.95g/cm³。

Comparative example 15

In example 15, rolling resistance characteristics, steering stability, and wet grip performance were evaluated in the same manner as in example 15 except that 25.7 parts by mass of extender oil 1 was blended so that the amount of the internal oil mixture including the components of extender oil 1 in sample θ 6 became 30 parts by mass.

The density of the whole mixed oil used at this time was 0.95g/cm³。

Comparative example 16

In example 16, rolling resistance characteristics, steering stability, and wet grip performance were evaluated in the same manner as in example 16 except that 7 parts by mass of extender oil 1 was added instead of using the high-density oil 2.

The density of the whole mixed oil used at this time was 0.95g/cm³。

Comparative example 17

In example 17, rolling resistance characteristics, steering stability, and wet grip performance were evaluated in the same manner as in example 17 except that 70 parts by mass of extender oil 1 was added instead of using the high-density oil 1.

The density of the whole mixed oil used at this time was 0.95g/cm³。

The compounding compositions of examples 1 to 17 and comparative examples 1 to 17 are shown in tables 3 and 4, and the evaluation results of rolling resistance characteristics, steering stability and wet grip performance thereof are shown in tables 5 to 20.

The symbols in tables 3 and 4 are as follows.

6Vivamax5000 (density 1.02 g/cm)³)

7Vivatec500 (density 0.95 g/cm)³)

8Vivamax5100 (density 1.01 g/cm)³)

Density of 9 oil monolith (high density oil + extender oil + modified silicone oil)

10SH510 (density 0.99 g/cm)³)

11Nytex4700 (density 0.94 g/cm)³)

12DCPD (hydrogenated cyclopentadiene)

13T160 (modified terpene phenol resin)

[ TABLE 3]

[ TABLE 5]

[ TABLE 6]

[ TABLE 7]

[ TABLE 8]

[ TABLE 9]

[ TABLE 10]

[ TABLE 11]

[ TABLE 12]

[ TABLE 13]

[ TABLE 14]

[ TABLE 15]

[ TABLE 16]

[ TABLE 17]

[ TABLE 18 ]

[ TABLE 19 ]

[ TABLE 20 ]

As is clear from tables 5 to 20, the rubber compositions of the present invention are highly excellent in the balance of rolling resistance characteristics, steering stability and wet grip performance.

On the other hand, as shown in comparative examples 1 to 17, it was found that the density of the conventional extender oil was not satisfied at 1.0g/cm³The composition (A) is poor in balance among rolling resistance characteristics, steering stability and wet grip.

Industrial applicability

The modified conjugated diene polymer composition of the present invention is industrially useful as a base tread for a tire and a material for a tire.

Claims

1. A modified conjugated diene polymer composition comprising a rubber component and an oil (ii),

the rubber component contains a modified conjugated diene polymer (i) having an adsorption property to a silica column, wherein the ratio Mw/Mn of the weight average molecular weight Mw to the number average molecular weight Mn, which is obtained by Gel Permeation Chromatography (GPC), is less than 1.5,

wherein the oil (ii) has a density of more than 1.0g/cm³。

2. The modified conjugated diene polymer composition according to claim 1, wherein the composition further contains a silica-based inorganic filler.

3. A modified conjugated diene polymer composition comprising a rubber component, a silica-based inorganic filler and an oil (ii),

wherein the oil (ii) has a density of 1.0g/cm³The above.

4. The modified conjugated diene polymer composition according to claim 1 or 3, wherein the modification ratio of the modified conjugated diene polymer (i) is 60% by mass or more.

5. The modified conjugated diene polymer composition according to claim 1 or 3, wherein the composition contains 1 to 300 parts by mass of a silica inorganic filler per 100 parts by mass of the modified conjugated diene polymer (i).

6. The modified conjugated diene polymer composition according to claim 1 or 3, wherein the composition further contains carbon black.

7. The modified conjugated diene polymer composition according to claim 1 or 3, wherein the composition is a composition for a base tread.

8. A tire comprising a base tread comprising a crosslinked product of the modified conjugated diene polymer composition according to any one of claims 1 to 7.