RU2793934C1 - Conjugated diene-based polymer, branching agent, conjugated diene-based polymer production method, conjugated diene-based oil-filled polymer, rubber composition and tire - Google Patents

Abstract

FIELD: polymer chemistry.

SUBSTANCE: material which can be used in industry as a material for tire treads, interior/exterior trim of vehicles, anti-vibration rubbers, belts, shoes, foam bodies and various industrial products. A polymer based on a conjugated diene is described, characterized by the number of branches (Bn), measured according to SEC measurement of light scattering using a viscosity detector, and amounting to 8 or more, demonstrating a change (ΔT) in the oxidation temperature due to the application of a thermal load of 11.9°C or less, and containing a monomeric aromatic vinyl compound unit. Methods for producing a conjugated diene-based polymer, an oil-filled conjugated diene-based polymer, a rubber composition, and a tire are also described.

EFFECT: providing a polymer based on a conjugated diene, which is characterized by recyclability and heat resistance when obtaining a vulcanizate from it.

17 cl, 8 tbl, 63 ex

Description

The field of technology to which the invention belongs

[0001]

The present invention relates to a conjugated diene based polymer, a branching agent, a process for producing a conjugated diene based polymer, an oil-filled conjugated diene based polymer, a rubber composition, and a tire.

State of the art

[0002]

There is an increasing need to reduce fuel consumption in vehicles, and improvements are needed in vehicle tire materials, in particular the tire tread in contact with the ground.

Recently, the development of a material having low rolling resistance, namely, showing the characteristics of low hysteresis loss, has been required.

In addition, in order to reduce the weight of the tire, it is necessary to reduce the thickness of the tread portion of the tire, and there is also a need for a material having high abrasion resistance.

On the other hand, from a safety point of view, a material used for a tire tread is required which is excellent in wet skid resistance and exhibits sufficient fracture performance in practice.

[0003]

One example of a rubber material that meets the above requirements includes a rubber material containing a rubbery polymer and a reinforcing filler such as carbon black and silica.

By using a rubber material containing silica, the balance between low hysteresis loss performance and wet skid resistance can be improved. In addition, an attempt has been made to reduce the hysteresis loss by improving the dispersibility of silica in the rubber material by introducing a functional group having an affinity or reactivity towards silica into the high mobility end of the rubber-like polymer molecule, and furthermore , as a result of a decrease in the mobility of the end of the rubbery polymer molecule due to the presence of a bond with a particle of silicon dioxide.

[0004]

For example, Patent Documents 1 to 3 propose a composition of a modified conjugated diene based polymer obtained by reacting an alkoxysilane containing an amino group and an active end of a conjugated diene based polymer and silica.

In addition, Patent Document 4 proposes a modified conjugated diene based polymer obtained by a coupling reaction between the active end of the polymer and a polyfunctional silane compound.

List of prior art documents

patent document

[0005]

Patent Document 1: Japanese Patent Laid-Open No. 2005-290355

Patent Document 2: Japanese Patent Laid-Open No. 11-189616

Patent Document 3: Japanese Patent Laid-Open No. 2003-171418

Patent Document 4: International Publication No. WO07/114203

The essence of the invention

Problems Solved by the Invention

[0006]

According to the above description of the invention, various polymers have been designed by introducing into the conjugated diene-based polymer a functional group having an affinity or reactivity for a carbon dioxide particle to effectively promote a reaction between the silica and the functional group, and, as noted by the inventors of the present invention, the thermal stress resistance, namely heat resistance, in the kneading process for producing a vulcanizate needs to be improved in order to demonstrate the desired performance as a tire composition by the polymer thus realized.

In other words, even if the polymer design is accurately realized as a result of end modification and the like, performance as a tire composition is degraded, unless the thus developed polymer structure with the design thus realized cannot be maintained in the silica kneading step. and the like.

The modified conjugated diene-based polymers disclosed in the above-described Patent Documents 1 to 4 have a problem in that they still retain a life of improving heat resistance.

[0007]

Therefore, one object of the present invention is to provide a conjugated diene-based polymer that is exceptionally excellent in processability and heat resistance in the preparation of a vulcanizate therefrom.

Troubleshooting Tools

[0008]

As a result of serious studies carried out to solve the problem of conventional techniques, the inventors of the present invention found that a conjugated diene-based copolymer characterized by the number of branches (Bn) and change (ΔT) of the temperature of the onset of oxidation due to the application of heat load, when hit, respectively , of both values in specific ranges, is extremely excellent in processability and heat resistance in making a vulcanizate therefrom, and thus the present invention has been completed.

Specifically, the present invention proposes the following:

[0009]

[1]

A conjugated diene-based polymer having a number of branches (Bn) measured according to a light scattering measurement in a GPC method equipped with a viscosity detector and being 8 or more, showing a change (ΔT) in the oxidation start temperature due to the application of a heat load of 11.9° C or less, and containing a monomeric aromatic vinyl compound unit.

[2]

The conjugated diene-based polymer corresponding to the above-described position [1], wherein the change (ΔT) of the oxidation start temperature due to the application of heat load is 10° C. or less.

[3]

A polymer based on a conjugated diene corresponding to the positions described above [1] or [2] and characterized by a degree of modification of 60% (wt.) or more.

[4]

The conjugated diene-based polymer corresponding to any one of [1] to [3] described above, wherein the content of the monomeric aromatic vinyl compound unit is 10% (mass) or more.

[5]

The conjugated diene based polymer corresponding to any one of [1] to [4] described above, wherein the conjugated diene based polymer is a conjugated diene based polymer having a star polymer structure having 3 or more branches, at least one the branched chain of the star polymer structure contains a portion derived from a vinyl-based monomer containing an alkoxysilyl group or a halosilyl group, and a portion derived from a vinyl-based monomer containing an alkoxysilyl group or a halosilyl group furthermore has a branched backbone structure.

[6]

The conjugated diene-based polymer corresponding to [5] above, wherein the portion derived from a vinyl-based monomer containing an alkoxysilyl group or a halosilyl group is a monomeric unit based on a compound represented by the following formulas (1) or (2 ), and contains a branching point of the polymer chain containing a monomeric elementary unit based on the compound described by formulas (1) or (2), and at least one end of the polymer based on the conjugated diene is modified using a group containing a nitrogen atom:

[0010]

, (1)

, (1)

[0011]

, (2)

, (2)

[0012]

where in the formula (1) R ¹ represents a hydrogen atom, an alkyl group containing from 1 to 20 carbon atoms, or an aryl group containing from 6 to 20 carbon atoms, and may have a branched structure in its part; each of R ² and R ³ is independently an alkyl group of 1 to 20 carbon atoms or an aryl group of 6 to 20 carbon atoms, and may have a branched structure in part; each R ¹ to R ³ when present in the plural is, respectively, independent; X ¹ represents an independent halogen atom; and m is an integer in the range of 0 to 2, n is an integer in the range of 0 to 3, l is an integer in the range of 0 to 3, and (m+n+l) is 3; And

in the formula (2), each R ² to R ⁵ independently represents an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and may have a branched structure in its part, and each from R ² to R ⁵ when present in the plural is, respectively, independent; X ² and X ³ represent an independent halogen atom; m is an integer in the range of 0 to 2, n is an integer in the range of 0 to 3, l is an integer in the range of 0 to 3, and (m+n+l) is 3; and a is an integer in the range of 0 to 2, b is an integer in the range of 0 to 3, c is an integer in the range of 0 to 3, and (a+b+c) is 3.

[0013]

[7]

The conjugated diene-based polymer corresponding to the above position [6] and containing a monomeric elementary unit based on the compound described by the formula (1), where R ¹ represents a hydrogen atom, and m is 0.

[8]

A conjugated diene based polymer corresponding to [6] above and containing a monomeric unit based on a compound represented by formula (2), where m is 0 and b is 0.

[9]

The conjugated diene-based polymer corresponding to [6] above and containing a monomeric unit based on the compound represented by formula (1), where R ¹ is a hydrogen atom, m is 0, and l is 0.

[10]

The conjugated diene-based polymer corresponding to [6] above and containing a monomeric unit based on the compound represented by formula (2), where m is 0, l is 0, a is 0, and b is 0.

[eleven]

The conjugated diene-based polymer corresponding to the above position [6] and containing a monomeric elementary unit based on the compound described by the formula (1), where R ¹ represents a hydrogen atom, l is 0, and n is 3.

[12]

The branching agent for the conjugated diene based polymer corresponding to [6] above, wherein the branching agent is a compound represented by the following formulas (1) or (2):

[0014]

, (1)

, (1)

[0015]

, (2)

, (2)

[0016]

where in the formula (1) R ¹ represents a hydrogen atom, an alkyl group containing from 1 to 20 carbon atoms, or an aryl group containing from 6 to 20 carbon atoms, and may have a branched structure in its part;

each of R ² and R ³ is independently an alkyl group of 1 to 20 carbon atoms or an aryl group of 6 to 20 carbon atoms, and may have a branched structure in part;

each R ¹ to R ³ when present in the plural is, respectively, independent;

X ¹ represents an independent halogen atom;

m is an integer in the range of 0 to 2, n is an integer in the range of 0 to 3, l is an integer in the range of 0 to 3, and (m+n+l) is 3;

in the formula (2), each R ² to R ⁵ independently represents an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and may have a branched structure in its part, and each from R ² to R ⁵ when present in the plural is, respectively, independent;

X ² and X ³ represent an independent halogen atom;

m is an integer in the range of 0 to 2, n is an integer in the range of 0 to 3, l is an integer in the range of 0 to 3, and (m+n+l) is 3; And

a is an integer in the range of 0 to 2, b is an integer in the range of 0 to 3, c is an integer in the range of 0 to 3, and (a+b+c) is 3.

[0017]

[13]

The branching agent corresponding to [12] above, wherein the branching agent is a compound represented by the formula (1), where R ¹ is a hydrogen atom and m is 0.

[14]

The branching agent corresponding to [12] above, wherein the branching agent is the compound represented by the formula (2), where m is 0 and b is 0.

[15]

The branching agent corresponding to [12] above, wherein the branching agent is a compound represented by formula (1), where R ¹ is a hydrogen atom, m is 0, and l is 0.

[16]

The branching agent corresponding to [12] above, wherein the branching agent is a compound represented by formula (2), where m is 0, l is 0, a is 0, and b is 0.

[17]

The branching agent corresponding to [12] above, wherein the branching agent is a compound represented by formula (1), where R ¹ is a hydrogen atom, l is 0, and n is 3.

[18]

A process for producing a polymer based on a conjugated diene corresponding to any one of [1] to [11] described above, comprising: a polymerization/branching step in the form of polymerization of at least a conjugated diene compound in the presence of an organolithium-based compound to obtain a polymer based on based on a conjugated diene having a backbone branching structure using a branching agent corresponding to any one of [12] to [17] above.

[19]

A method for producing a conjugated diene-based polymer, comprising: a step of polymerizing a conjugated diene compound and an aromatic vinyl compound in the presence of an organolithium-based compound to obtain a copolymer; a step of reacting a copolymer of a conjugated diene compound and an aromatic vinyl compound and a vinyl-based monomer containing an alkoxysilyl group or a halosilyl group to obtain a branched main chain structure; and a step of polymerizing a polymer chain having a backbone branching structure with at least a conjugated diene compound.

[20]

A process for producing a conjugated diene based polymer according to [18] or [19] above, further comprising a modification step of modifying the conjugated diene based polymer using a modifier containing a group containing a nitrogen atom, where the modifier includes a modifier , which is described by any one of the following formulas from (A) to (C):

[0018]

, (А)

, (A)

[0019]

where each R ¹ to R ⁴ independently represents an alkyl group containing from 1 to 20 carbon atoms, or an aryl group containing from 6 to 20 carbon atoms, R ⁵ represents an alkylene group containing from 1 to 10 carbon atoms, and R ⁶ is an alkylene group containing from 1 to 20 carbon atoms; and m is an integer of 1 or 2, n is an integer of 2 or 3, (m+n) is an integer of 4 or more, and each R ¹ to R ⁴ when plural is, respectively, independent;

[0020]

, (B)

, (B)

[0021]

where each R ¹ to R ⁶ independently represents an alkyl group containing from 1 to 20 carbon atoms, or an aryl group containing from 6 to 20 carbon atoms, and each from R ⁷ to R ⁹ independently represents an alkylene group containing from 1 to 20 carbon atoms; and each m, n and l is independently an integer in the range of 1 to 3, (m+n+l) is an integer of 4 or more, and each R ¹ to R ⁶ when plural is, accordingly, independent;

[0022]

, (C)

, (C)

[0023]

where each R ¹² to R ¹⁴ independently represents a single bond or an alkylene group containing from 1 to 20 carbon atoms, each from R ¹⁵ to R ¹⁸ and R ²⁰ independently represents an alkyl group containing from 1 to 20 carbon atoms, each of R ¹⁹ and R ²² is independently an alkylene group having 1 to 20 carbon atoms, R ²¹ is an alkyl group or a trialkylsilyl group having 1 to 20 carbon atoms; m is an integer ranging from 1 to 3 and p is 1 or 2; each R ¹² to R ²² , m and p, if present in the plural, are respectively independent and may be identical to or different from the others; i is an integer in the range 0 to 6, j is an integer in the range 0 to 6, k is an integer in the range 0 to 6, a (i+j+k) is an integer in the range from 4 to 10; and A is a hydrocarbon group containing 1 to 20 carbon atoms, or an organic group containing 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 containing no active hydrogen atom.

[0024]

[21]

The process for producing a conjugated diene-based polymer according to [20] above, wherein A is any one of the following general formulas from (II) to (V) in formula (C):

[0025]

, (II)

, (II)

[0026]

where In ¹ represents a single bond or a hydrocarbon group containing from 1 to 20 carbon atoms, and represents an integer in the range from 1 to 10, and In ¹ when present in the plural is, respectively, independent;

[0027]

, (III)

, (III)

[0028]

where B ² represents a single bond or a hydrocarbon group containing from 1 to 20 carbon atoms, B ³ represents an alkyl group containing from 1 to 20 carbon atoms, and represents an integer in the range from 1 to 10, and each of B ² and B ³ when present in the plural is, respectively, independent;

[0029]

,(IV)

,(IV)

[0030]

where B ⁴ represents a single bond or a hydrocarbon group containing from 1 to 20 carbon atoms, and represents an integer in the range from 1 to 10, and B ⁴ when present in the plural is, respectively, independent; And

[0031]

, (V)

, (V)

[0032]

where B ⁵ represents a single bond or a hydrocarbon group containing from 1 to 20 carbon atoms, a represents an integer in the range from 1 to 10, and B ⁵ when present in the plural is, respectively, independent.

[0033]

[22]

An oil-filled polymer based on a conjugated diene, containing 100 mass parts of a polymer based on a conjugated diene corresponding to any one of [1] to [11] described above; and from 1 to 60 mass parts of oil for filling.

[23]

A rubber composition containing a rubber component and from 5.0 mass parts or more to 150 mass parts or less of a filler based on 100 mass parts of the rubber component, where the rubber component contains 10% (mass) or more when calculating the total amount of the rubber component a conjugated diene-based polymer corresponding to any one of [1] to [11] described above, or an oil-filled conjugated diene-based polymer corresponding to [22] described above.

[24]

A tire containing a rubber composition corresponding to the above position [23].

Benefits of the Invention

[0034]

In accordance with the present invention, a conjugated diene-based polymer is obtained, which is characterized by exceptionally excellent processability and heat resistance in the preparation of a vulcanizate therefrom.

Method for carrying out the invention

[0035]

One embodiment for practicing the present invention (hereinafter referred to as "the present embodiment") will now be described in detail.

As it should be noted, the following present embodiment is merely one example for describing the present invention, and the present invention is not limited to the following description of the invention, but may be variously modified within its scope.

[0036]

[Conjugated diene polymer]

The conjugated diene-based polymer of the present embodiment has a number of branches (Bn) measured according to light scattering measurement in a GPC method equipped with a viscosity detector of 8 or more, and exhibits a change (ΔT) in the oxidation start temperature due to the application of heat load of 11 .9°C or less.

The conjugated diene-based polymer, as indicated, characterized by the number of branches and the change (ΔT) in the temperature of the onset of oxidation due to the application of heat load, in accordance with the above description of the invention, is characterized by exceptionally excellent processability and heat resistance when it is obtained from its vulcanizate.

As it should be noted, the term "conjugated diene polymer" in this document covers the modified conjugated diene polymer obtained after modification, unless otherwise stated.

[0037]

(Number of branches)

From the viewpoints of processability and heat resistance, the conjugated diene-based polymer of the present embodiment has a number of branches (Bn) of 8 or more.

The number of branches (Bn) of 8 or more indicates that the conjugated diene-based polymer of the present embodiment has 8 or more polymer chains as side chains with respect to the substantially longest polymer backbone.

The number of branches (Bn) for the conjugated diene polymer is determined using the shrinkage factor (g') measured according to light scattering measurement in a GPC method equipped with a viscosity detector, as g'=6Bn/{(Bn+1)(Bn+2 )}.

[0038]

In general, a polymer having a branch tends to exhibit a smaller molecule than a straight chain polymer having the same absolute molecular weight.

The shrinkage factor (g') is a measure of the size fraction occupied by a molecule in a straight chain polymer assuming identical absolute molecular weight. In other words, as the number of branches increases, the shrinkage factor (g’) tends to decrease.

For the shrinkage factor, intrinsic viscosity is used as an indicator of molecular size in this embodiment, and the straight chain polymer satisfies the relationship: intrinsic viscosity [ƞ]=10 ^{- 3.883} M ^0.771 , where M is the absolute molecular weight.

However, the shrinkage factor (g') expresses the degree of molecular size reduction and does not accurately express the branching structure of the polymer.

Therefore, the number of branches (Bn) for the conjugated diene based polymer is calculated using the shrinkage factor (g') obtained at each absolute molecular weight of the conjugated diene based polymer. Thus calculated "number of branches (Bn)" accurately expresses the number of polymers directly or indirectly associated with the structure of the longest main chain.

The calculated number of branches (Bn) may be an index expressing the branching structure of the conjugated diene based polymer. For example, in general, a 4-armed star polymer (having 4 polymer chains connected to a central site) has two arms of polymer chains associated with the structure of the longest highly branched backbone, and thus the number of branches (Bn) is estimated to be 2.

In a conventional 8-arm star polymer, 6 polymer chain arms are linked to the structure of the longest highly branched main chain, and the number of arms (Bn) is estimated to be 6.

The conjugated diene-based polymer of the present embodiment has a number of branches (Bn) of 8 or more, and such a case indicates the presence of a conjugated diene-based polymer having, as a star polymer structure, branches similar to that of a star polymer structure with 10 branches.

In this case, the "branch" is obtained as a result of the direct or indirect connection of one polymer with another polymer. In addition, the "number of branches (Bn)" corresponds to the number of polymers directly or indirectly linked to the structure of the longest backbone.

With a number of branches (Bn) of 8 or more, the conjugated diene-based polymer of the present embodiment is excellent in balance between low hysteresis loss performance and wet skid resistance when the material is in the form of a vulcanizate.

In general, an increase in absolute molecular weight tends to impair processability, and as absolute molecular weight increases in the structure of a straight chain polymer, the vulcanizate made from it exhibits a greatly increased viscosity and a greatly impaired processability. Therefore, even when a large amount of functional groups are introduced into the polymer to improve the affinity and/or reactivity with silica mixed as a filler, the silica cannot be sufficiently dispersed in the polymer during the kneading process. As a result, the function of the introduced functional groups cannot be exhibited, and thus the originally expected effect of improving the characteristics of small hysteresis loss and wet skid resistance due to the introduction of the functional groups cannot be exhibited.

On the other hand, since the conjugated diene-based polymer of the present embodiment has a number of branches (Bn) of 8 or more as described, the increase in the viscosity of the vulcanizate obtained therefrom due to the increase in absolute molecular weight is largely suppressed, and thus the polymer can be sufficiently mixed with silica and the like in a kneading process so that the silica can be dispersed throughout the conjugated diene-based polymer. As a result, abrasion resistance and fracture performance can be improved by setting a high molecular weight of the conjugated diene-based polymer, and, in addition, silica can be dispersed throughout the polymer by sufficient kneading to promote action and /or the reaction of functional groups, and thus the polymer can achieve sufficient characteristics of low hysteresis loss and wet skid resistance in practice.

The absolute molecular weight of the conjugated diene based polymer can be measured using the method described in the examples below.

[0039]

The number of branches (Bn) for the conjugated diene-based polymer of the present embodiment is 8 or more, preferably 10 or more, more preferably 12 or more, and further preferably 15 or more.

A conjugated diene-based polymer having a number of branches (Bn) falling within this range tends to exhibit excellent processability obtained when the material is used to make a vulcanizate.

The upper limit of the number of branches (Bn) is not particularly limited and may be equal to or greater than the detection limit, and is preferably 84 or less, more preferably 80 or less, further preferably 64 or less, and furthermore preferably 57 and less.

In the case of the number of branches being 84 or less, the abrasion resistance obtained by using the material for producing the vulcanizate tends to be excellent.

The number of branches for the conjugated diene-based polymer can be adjusted to 8 or more according to the combination of the amount of branching agent added and the amount of end modifier added. Specifically, the number of branches can be adjusted by adjusting the number of functional groups of the branching agent, the amount of the branching agent added, the timing for adding the branching agent, and the amount of the modifier added. A more specific description will be given in the following section [Method for producing polymer based on conjugated diene].

[0040]

The conjugated diene based polymer of the present embodiment contains a monomeric aromatic vinyl compound unit.

By increasing the weight fraction of the aromatic vinyl compound monomeric unit in the conjugated diene polymer, the thermal stability of the conjugated diene polymer can be improved.

From the viewpoint of improving heat resistance, the mass fraction of the monomeric aromatic vinyl compound unit in the conjugated diene-based polymer of the present embodiment is preferably 1% (mass) or more, and from the point of view of appreciably obtaining uneven distribution of the monomeric aromatic vinyl compound unit in the outer portion , and especially at the end portion, of the conjugated diene-based polymer according to the following description of the invention is more preferably 5% (mass.) or more, and, in addition, preferably 10% (mass.) or more.

From the viewpoint of obtaining sufficient low hysteresis loss characteristics in practice, the mass fraction is preferably less than 60% (mass), more preferably 50% (mass) or less, and further preferably 40% (mass) and less.

The term “conjugated diene-based polymer end” means a polymerization start end, and the content of the monomeric aromatic vinyl compound unit at this end is preferably 1% (mass) or more.

[0041]

With uneven distribution of the aromatic vinyl compound monomeric unit on the outer region of the conjugated diene polymer in the three-dimensional structure of the conjugated diene polymer, the heat resistance of the conjugated diene polymer can be expected to be increased, but it is difficult to directly consider the three-dimensional structure of the conjugated diene polymer.

As considered by the inventors of the present invention, "the change (ΔT) in the oxidation start temperature due to the application of heat load", measured in the state when the conjugated diene-based polymer is present in three-dimensional form, reflects the three-dimensional structure of the conjugated diene-based polymer, resulting in to the completion of the present invention.

The change (ΔT) in the temperature of the onset of oxidation due to the application of thermal load reflects the three-dimensional structure, presumably based on the production conditions, and is considered as a measurement result corresponding to the three-dimensional structure of the polymer, although indirectly.

By changing (ΔT) the oxidation initiation temperature due to the application of heat load equal to or less than the set value, the resistance to kneading conducted by using the conjugated diene-based polymer of the present embodiment as the material of the tire composition increases, and thus thermal aging of the polymer can be sufficiently prevented. In other words, the change (ΔT) to a very large extent also relates to the performance of the tire composition.

With the conjugated diene-based polymer of the present embodiment, the change (ΔT) of the oxidation start temperature due to the application of heat load is 11.9°C or less as indicated, and thus excellent heat resistance is obtained.

The change in oxidation start temperature due to the application of a heat load can be specifically measured using the method described below.

[0042]

In general, a copolymer containing a monomeric aromatic vinyl compound unit tends to exhibit excellent heat resistance compared to a conjugated diene compound homopolymer, and in an aromatic vinyl compound-conjugated diene compound copolymer, the polymerized portion of the aromatic vinyl compound is more excellent in heat resistance than polymerized site of the conjugated diene compound.

As expected, the polymer is present in a state of non-linear but three-dimensional assembly. In this three-dimensional configuration, by non-uniformly distributing the polymerized portion of the aromatic vinyl compound having increased heat resistance on the outer portion of the conjugated diene-based polymer easily subjected to heat stress, the heat resistance of the conjugated diene-based polymer can be generally improved.

In other words, by increasing the proportion of monomeric aromatic vinyl compound unit in the outer portion of the polymer chain, the heat resistance of the conjugated diene polymer can be further improved.

There are no restrictions on the method of increasing the proportion of the monomeric elementary unit of an aromatic vinyl compound in the outer region of the polymer chain, and, for example, when obtaining a star-branched polymer based on a conjugated diene, by stimulating the entry of a polyfunctional coupling reaction agent into the reaction with the polymerization-terminating end, the agent the coupling reaction is easily placed on the central side of the three-dimensional configuration, and thus the polymerization start side is easily placed on the outside. Therefore, the copolymerization is carried out with a large proportion of the aromatic vinyl compound immediately after the start of the polymerization, and the copolymerization is carried out with the proportion of the conjugated diene compound increased immediately before the end of the polymerization, and then the coupling reaction is carried out. Thus, the monomeric aromatic vinyl compound unit is easily unevenly distributed in the outer portion of the three-dimensional structure. In addition, by obtaining a backbone branching structure in the vicinity of the polymerization start end, by using a polymer chain having a high proportion of the monomeric aromatic vinyl compound unit, the effect of uneven distribution of the monomeric aromatic vinyl compound unit at the outer portion can be further increased. In other words, the heat resistance can be improved by increasing the number of branches described above.

Specifically, it is preferable to use, in the branched structure of the conjugated diene-based polymer described below, a method in which the proportion of the monomeric aromatic vinyl compound unit at the outer portion of the branched chain is increased. From the viewpoint of improving heat resistance, the number of legs is preferably 8 or more.

In addition, from the point of view of non-uniform distribution of the monomeric unit unit of the aromatic vinyl compound at the outer portion, also one example of a preferred structure is the structure obtained by branching an aromatic vinyl polymer chain as a main chain, then obtaining a conjugated diene block, and passing to the resulting the result of a coupling reaction product to form multiple branching. However, from the point of view of tire performance, as a conjugated diene-based polymer used in a tire composition, a polymer in the form of a random copolymer of aromatic vinyl and conjugated diene compounds is preferable by varying the ratio between them between the outer region and the inner region (wherein the outer the site is enriched in aromatic vinyl compound).

[0043]

As a method for increasing the proportion of the monomeric aromatic vinyl compound unit in the branched chain of the random copolymer, the proportion of the monomeric aromatic vinyl compound unit at the outer portion of the polymer chain, for example, can be increased in the polymerization step of the conjugated diene compound and the aromatic vinyl compound by disjointly adding the conjugated diene connections.

One example of a conjugated diene compound includes 1,3-butadiene and one example of an aromatic vinyl compound includes styrene.

In the polymerization step of the conjugated diene compound and the aromatic vinyl compound, a method can be used in which the copolymerization reaction is started with all of the styrene and part of the 1,3-butadiene present, and the remaining 1,3-butadiene is intermittently added during the copolymerization reaction. The amount of remaining 1,3-butadiene added discontinuously is not particularly limited, and is preferably 30% or more, more preferably 35% or more, and further preferably 40% or more of the total amount of 1,3-butadiene. When the amount of 1,3-butadiene added discontinuously falls within this range, the proportion of styrene in this case tends to improve, which improves the heat resistance of the branched chain.

As used herein, the term "random copolymer" refers to a polymer in which an aromatic vinyl compound and a conjugated diene compound are randomly polymerized without regularity.

From the viewpoint of low fuel consumption performance, the randomly polymerized conjugated diene polymer preferably either contains few or no blocks, each of which has 30 or more aromatic vinyl units linked in a chain. More specifically, in the case of a conjugated diene-based polymer in the form of styrene-butadiene copolymer, based on the use of a known method in which the copolymer is decomposed using the Kolthoff method (the method described in I. M. Kolthoff, et al., J. Polym. Sci. 1, 429 (1946)) to analyze the amount of polystyrene insoluble in methanol, the number of blocks in each of which 30 or more aromatic vinyl units are connected in a chain is preferably 5.0% (wt.) or less, and more preferably 3.0% (mass.) or less, when calculating the total amount of the polymer based on the conjugated diene.

[0044]

(Change (ΔT) in the oxidation start temperature due to the application of heat load)

The conjugated diene-based polymer of the present embodiment has an oxidation start temperature change (ΔT) due to application of heat load of 11.9°C or less, preferably 10°C or less, and more preferably 8°C or less.

The term "thermal load application" refers to the application of thermal energy to a conjugated diene based polymer. The term "thermal energy application" refers to the application of thermal energy to a conjugated diene based polymer.

The term “oxidation start temperature” refers to the temperature at which a conjugated diene-based polymer undergoes an oxidation reaction that increases its mass when heated in air.

Specifically, a heat load is applied using 50 g of a conjugated diene based polymer loaded into a Labo Plastomill 30C150 (Toyo Seiki Seisaku-sho, Ltd.) and the bulk temperature set to 50° C. after three kneading cycles. , in each of which kneading is carried out at 120 rpm for 5 minutes, and then stopped for 5 minutes. The heat load may be determined according to the amount of heat per unit time, but thus the viscosity of the polymer and the like affect the amount of heat generated, which may degrade reproducibility. Therefore, it is effective to indicate the heat load using the specific techniques described above.

When the conjugated diene-based polymer exhibits a change (ΔT) in the oxidation initiation temperature due to the application of a heat load falling within this range, the heat resistance when preparing a vulcanizate therefrom tends to exhibit an excellent value.

The change in the temperature of the onset of oxidation due to the application of a thermal load can be measured using the method described in the examples in this document.

[0045]

(Degree of modification)

From the viewpoints of the balance between the characteristics of low hysteresis loss and wet slip resistance, abrasion resistance, and fracture characteristics, the conjugated diene-based polymer of the present embodiment preferably has a degree of modification of 60% (mass) or more based on the total amount of a polymer based on a conjugated diene.

In this document, the term "degree of modification" refers to the weight ratio between the conjugated diene-based polymer containing a nitrogen-containing functional group and the total amount of conjugated diene-based polymers.

For example, based on the assumption of a reaction between the nitrogen-containing modifier and the terminal end, the weight ratio between the conjugated diene-based polymer containing the nitrogen-containing functional group due to the nitrogen-containing modifier and the total amount of conjugated diene-based polymers is expressed as the degree of modification.

On the other hand, also when the polymer is branched using a nitrogen-containing branching agent, the conjugated diene-based polymer thus produced contains a nitrogen-containing functional group, and such a branched polymer is also taken into account when calculating the degree of modification.

In other words, herein, when a conjugated diene based polymer in the form of, in particular, a "modified conjugated diene based polymer" has undergone modification, the degree of modification corresponds to the mass fraction of the sum of the reacted coupling of the polymer obtained using a modifier containing a nitrogen-containing functional group, and/or a branched polymer obtained by using a branching agent containing a nitrogen-containing functional group.

When the polymer contains a nitrogen-containing functional group, the performance required of the tire composition, such as the balance between low hysteresis loss performance and wet skid resistance, can be improved.

By changing (ΔT) the oxidation initiation temperature due to the application of a heat load having a particular significance and modifying the conjugated diene-based polymer, the conjugated diene-based polymer can easily maintain a favorable structure even in a kneading process with a filler such as silica, and the composition using a conjugated diene-based polymer tends to show the desired effect easily.

The degree of modification of the conjugated diene polymer of the present embodiment is more preferably 65% (mass) or more, furthermore, preferably 70% (mass) or more, furthermore, preferably 75% (mass) or more, except moreover, preferably 80% (wt.) or more, and particularly preferably 82% (wt.) or more.

For the case of the degree of modification of 60% (wt.) or more, the resulting polymer tends to show excellent processability obtained when using the material to obtain a vulcanizate, and more excellent abrasion resistance and low hysteresis loss characteristics when found material in the form of a vulcanizate.

[0046]

The degree of modification can be measured using chromatography capable of separating the modified functional group-containing component from the unmodified component.

As a method using chromatography, a method using a gel permeation chromatography column using a polar material such as silica adsorbing a specific functional group as a filler can be used to carry out a quantitative determination using an internal standard in the form of a non-adsorbed component.

More specifically, the degree of modification is obtained by measuring the amount of adsorption on a silica column based on the difference between a chromatogram measured using a polystyrene-based gel column and a chromatogram measured using a silica-based column obtained from a sample solution, containing the sample and a low molecular weight polystyrene internal standard. More specifically, the degree of modification is measured using the method described in the examples below.

[0047]

With the conjugated diene-based polymer of the present embodiment, the degree of modification can be adjusted by adjusting the addition amount of the modifier and the reaction method, and thus can be adjusted to 60% (mass) or more.

For example, a method in which polymerization is carried out using as the polymerization initiator the following organolithium compound containing at least one nitrogen atom in a molecule, a method in which a monomer containing at least one nitrogen atom in a molecule is copolymerized , and a method in which a modifier having the structural formula described below is used and polymerization conditions are controlled, and thus a degree of modification can be obtained.

[0048]

(Branching structure)

From the viewpoints of the balance of processability and abrasion resistance, the conjugated diene polymer of the present embodiment is preferably a conjugated diene polymer having a star polymer structure having 3 or more branches, in which at least one branched chain of the star polymer structure comprises a portion derived from a vinyl-based monomer containing an alkoxysilyl group or a halosilyl group and a portion derived from a vinyl-based monomer containing an alkoxysilyl group or a halosilyl group further contain a branched main chain structure.

As used herein, the term "star polymer structure" refers to a structure in which a plurality of polymer chains (arms) are linked to a single central branch point.

One central branch point herein contains a substituent containing a nitrogen atom.

The term “main chain branching structure” herein refers to a structure in which a polymer chain forms a branch point at a site derived from a vinyl-based monomer containing an alkoxysilyl group or a halosilyl group, and the polymer chain (beam) extends from the branch point.

[0049]

From the viewpoint of improving the number of Bn branches of the conjugated diene-based polymer of the present embodiment, the number of branching points of the main chain branching structure formed by the portion derived from the vinyl-based monomer containing an alkoxysilyl group or a halosilyl group is 4 or more, and the structure with branching derived from the star polymer structure obtained by using the modifier in the modification step preferably includes 3 or more branches, more preferably 4 or more branches, and further preferably 8 or more branches.

Despite the increase in the number of Bn branches, both as a result of modification using a coupling agent to obtain a star structure, and as a result of introducing a branching agent into the polymer, the contribution to the number of Bn branches is large when the entire polymer chain is branched using a coupling agent.

When implementing the polymer design, the number of Bn branches can be adjusted according to the selection of the coupling agent and the type and setting of the branching agent, and tends to be able to easily adjust the number of Bn branches by taking into account the contribution rate.

[0050]

<Main chain branch structure>

The main chain branching structure according to the above description of the invention is a structure having a branching point at a site derived from a vinyl-based monomer containing an alkoxysilyl group or a halosilyl group, and the number of branching points is 2 or more, preferably 3 or more, and more preferably 4 or more.

The branching point of the backbone branch structure preferably has at least 2 or more polymer chains, more preferably 3 or more non-main chain polymer chains, and further preferably 4 or more non-main chain polymer chains.

[0051]

<Star Resin Structure>

From the viewpoint of being able to easily obtain a structure in which the aromatic vinyl compound monomeric unit is unevenly distributed in the outer portion, the conjugated diene-based polymer of the present embodiment preferably has the star polymer structure according to the above description. The number of branches produced from the star polymer structure is preferably 3 or more, more preferably 4 or more, further preferably 6 or more, and furthermore preferably 8 or more.

[0052]

In the method for producing, as a conjugated diene polymer of the present embodiment, a conjugated diene polymer having a star polymer structure of 3 or more branches, in which at least one branched chain of the star polymer structure contains a portion derived from a monomer on vinyl base containing an alkoxysilyl group or a halosilyl group, and a portion derived from a vinyl-based monomer containing an alkoxysilyl group or a halosilyl group further contains a branched main chain structure, "star polymer structure" can be obtained by adjusting the amount functional groups of the modifier and the amount of modifier added, and "backbone branching structure" can be adjusted by adjusting the number of functional groups of the branching agent, the amount of the branching agent added, and the timing for adding the branching agent.

[0053]

In order to obtain a conjugated diene-based polymer having a star polymer structure having 3 or more branches, in which at least one branched chain of the star polymer structure contains a site derived from a vinyl-based monomer containing an alkoxysilyl group or a halosilyl group, and a portion derived from a vinyl-based monomer containing an alkoxysilyl group or a halosilyl group further contains a branched main chain structure, for example, a method in which polymerization is carried out using an organolithium-based compound as the polymerization initiator can be used, during or after polymerization, a branching agent is added to give a specific branching point, and modification is carried out using a modifier to give a specific degree of branching after continued polymerization.

Controls for such polymerization conditions will be described below as a production method in the examples.

[0054]

(Detailed structure for main chain branching structure)

From the viewpoint of being able to easily obtain the above-described structure in which the aromatic vinyl compound monomeric unit is unevenly distributed in the outer region, the conjugated diene-based polymer of the present embodiment is preferably branched.

This is because the conjugated diene-based polymer can be easily designed to obtain improved heat resistance when branching the main branch, and, in addition, uneven distribution of the monomeric aromatic vinyl compound unit on the end side of the polymer is promoted.

The branch preparation means is not particularly limited, and from the point of view described above, it is preferable that the conjugated diene polymer of the present embodiment contain a portion derived from a vinyl-based monomer containing an alkoxysilyl group or a halosilyl group in at least one branched chains of a star structure, further containing a site derived from a vinyl-based monomer containing an alkoxysilyl group or a halosilyl group, branched structures of the main chain, and having a site derived from a vinyl-based monomer containing an alkoxysilyl group or a halosilyl group, in the form monomeric elementary unit based on the compound described by the following formulas (1) or (2), and the inclusion of a branch point of the polymer chain containing the monomeric elementary unit based on the compound described by formulas (1) or (2).

In addition, at least one end of the conjugated diene-based polymer is preferably modified using a group containing a nitrogen atom.

[0055]

(1)

(1)

[0056]

(2)

(2)

[0057]

In the formula (1), R ¹ represents a hydrogen atom, an alkyl group containing 1 to 20 carbon atoms, or an aryl group containing 6 to 20 carbon atoms, and may have a branched structure in its part; each of R ² and R ³ is independently an alkyl group of 1 to 20 carbon atoms or an aryl group of 6 to 20 carbon atoms and may have a branched structure in its part, and each of R ¹ to R ³ when present in the plural is, respectively, independent; X ¹ represents an independent halogen atom; and m is an integer in the range of 0 to 2, n is an integer in the range of 0 to 3, l is an integer in the range of 0 to 3, and (m+n+l) is 3.

In the formula (2), each R ² to R ⁵ independently represents an alkyl group containing 1 to 20 carbon atoms or an aryl group containing 6 to 20 carbon atoms, and may have a branched structure in its part; each R ² to R ⁵ when present in the plural is, respectively, independent; X ² and X ³ represent an independent halogen atom; m is an integer in the range of 0 to 2, n is an integer in the range of 0 to 3, l is an integer in the range of 0 to 3; (m+n+l) is 3; and a is an integer ranging from 0 to 2, b is an integer ranging from 0 to 3, c is an integer ranging from 0 to 3, and (a+b+c) is an integer 3 .

[0058]

The conjugated diene-based polymer of the present embodiment preferably contains a monomeric unit based on the compound represented by formula (1) in which R ¹ is a hydrogen atom and m is 0.

Thus, the number of branches is improved, and the effect of improving abrasion resistance and workability can be obtained.

[0059]

Alternatively, the conjugated diene based polymer of the present invention is preferably a conjugated diene based polymer containing a monomeric unit based on the compound represented by formula (2) in which m is 0 and b is 0.

Thus, an effect of improving abrasion resistance and processability can be obtained.

[0060]

In addition, alternatively, the conjugated diene-based polymer of the present embodiment preferably contains a monomeric unit based on the compound represented by formula (1) in which R ¹ is a hydrogen atom, m is 0, and l is 0.

Thus, the number of branches is improved, and the effect of improving abrasion resistance and workability is obtained.

[0061]

Alternatively, the conjugated diene based polymer of the present embodiment is preferably a conjugated diene based polymer containing a monomeric unit based on the compound represented by formula (2) in which m is 0, l is 0, a is 0, and b is 0.

Thus, an effect of improving abrasion resistance and processability can be obtained.

[0062]

The conjugated diene-based polymer of the present embodiment is more preferably a conjugated diene-based polymer containing a monomeric unit based on the compound represented by formula (1), where R ¹ is a hydrogen atom, l is 0, and n is 3.

Thus, the degree of modification and the number of branches are improved, and the effect of improving the performance of low fuel consumption, abrasion resistance and processability can be obtained.

[0063]

[Branching Agent]

In the conjugated diene-based polymer of the present embodiment, when constructing the main chain branching structure, the branching agent represented by the following formulas (1) or (2) is preferably used as the branching agent.

[0064]

(1)

(1)

[0065]

(2)

(2)

[0066]

In the formula (1), R ¹ represents a hydrogen atom, an alkyl group containing 1 to 20 carbon atoms, or an aryl group containing 6 to 20 carbon atoms, and may have a branched structure in its part.

Each of R ² and R ³ is independently an alkyl group of 1 to 20 carbon atoms or an aryl group of 6 to 20 carbon atoms, and may have a branched structure in part.

Each R ¹ to R ³ when present in the plural is, respectively, independent.

X ¹ represents an independent halogen atom.

m is an integer in the range 0 to 2, n is an integer in the range 0 to 3, l is an integer in the range 0 to 3, and

(m+n+l) is 3.

In the formula (2), each R ² to R ⁵ independently represents an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and may have a branched structure in part.

Each of R ² to R ⁵ when present in the plural is, respectively, independent.

X ² and X ³ represent an independent halogen atom.

m is an integer in the range 0 to 2, n is an integer in the range 0 to 3, l is an integer in the range 0 to 3, and

(m+n+l) is 3.

a is an integer in the range of 0 to 2, b is an integer in the range of 0 to 3, c is an integer in the range of 0 to 3, and (a+b+c) is 3.

[0067]

In the present embodiment, from the viewpoints of polymerization continuity and improvement of the number of branches, the branching agent used in constructing the backbone branching structure of the conjugated diene-based polymer is preferably a compound represented by the formula (1) in which R ¹ is a hydrogen atom, and m is 0.

[0068]

Alternatively, in the present embodiment, from the viewpoint of improving the number of branches, the branching agent used in constructing the conjugated diene-based polymer backbone branching structure is preferably a compound having the formula (2) in which m is 0 and b is 0.

[0069]

In the present embodiment, from the viewpoints of polymerization continuity and improvement of the degree of modification and the number of branches, the branching agent used in constructing the branching structure of the conjugated diene-based polymer backbone is more preferably a compound having the formula (1) in which R ¹ is is a hydrogen atom, m is 0, and l is 0.

[0070]

In the present embodiment, from the viewpoint of improving the degree of modification and the number of branches, the branching agent used in constructing the branching structure of the conjugated diene-based polymer backbone is preferably a compound having the formula (2) in which m is 0, l is 0 , a is 0, and b is 0.

[0071]

In the present embodiment, from the viewpoints of polymerization continuity and improvement of the degree of modification and the number of branches, the branching agent used in constructing the branching structure of the conjugated diene-based polymer backbone is more preferably a compound having the formula (1) in which R ¹ is is a hydrogen atom, l is 0 and n is 3.

[0072]

Examples of the branching agent represented by formula (1) include, but are not limited to, trimethoxy(4-vinylphenyl)silane, triethoxy(4-vinylphenyl)silane, tripropoxy(4-vinylphenyl)silane, tributoxy(4-vinylphenyl)silane , triisopropoxy(4-vinylphenyl)silane, trimethoxy(3-vinylphenyl)silane, triethoxy(3-vinylphenyl)silane, tripropoxy(3-vinylphenyl)silane, tributoxy(3-vinylphenyl)silane, triisopropoxy(3-vinylphenyl)silane, trimethoxy (2-vinylphenyl)silane, triethoxy(2-vinylphenyl)silane, tripropoxy(2-vinylphenyl)silane, tributoxy(2-vinylphenyl)silane, triisopropoxy(2-vinylphenyl)silane, dimethoxymethyl(4-vinylphenyl)silane, diethoxymethyl(4 -vinylphenyl)silane, dipropoxymethyl(4-vinylphenyl)silane, dibutoxymethyl(4-vinylphenyl)silane, diisopropoxymethyl(4-vinylphenyl)silane, dimethoxymethyl(3-vinylphenyl)silane, diethoxymethyl(3-vinylphenyl)silane, dipropoxymethyl(3-vinylphenyl) )silane, dibutoxymethyl(3-vinylphenyl)silane, diisopropoxymethyl(3-vinylphenyl)silane, dimethoxymethyl(2-vinylphenyl)silane, diethoxymethyl(2-vinylphenyl)silane, dipropoxymethyl(2-vinylphenyl)silane, dibutoxymethyl(2-vinylphenyl)silane , diisopropoxymethyl(2-vinylphenyl)silane, dimethylmethoxy(4-vinylphenyl)silane, dimethylethoxy(4-vinylphenyl)silane, dimethylpropoxy(4-vinylphenyl)silane, dimethylbutoxy(4-vinylphenyl)silane, dimethylisopropoxy(4-vinylphenyl)silane, dimethylmethoxy (3-vinylphenyl)silane, dimethylethoxy(3-vinylphenyl)silane, dimethylpropoxy(3-vinylphenyl)silane, dimethylbutoxy(3-vinylphenyl)silane, dimethylisopropoxy(3-vinylphenyl)silane, dimethylmethoxy(2-vinylphenyl)silane, dimethylethoxy(2 -vinylphenyl)silane, dimethylpropoxy(2-vinylphenyl)silane, dimethylbutoxy(2-vinylphenyl)silane, dimethylisopropoxy(2-vinylphenyl)silane, trimethoxy(4-isopropenylphenyl)silane, triethoxy(4-isopropenylphenyl)silane, tripropoxy(4-isopropenylphenyl) )silane, tributoxy(4-isopropenylphenyl)silane, triisopropoxy(4-isopropenylphenyl)silane, trimethoxy(3-isopropenylphenyl)silane, triethoxy(3-isopropenylphenyl)silane, tripropoxy(3-isopropenylphenyl)silane, tributoxy(3-isopropenylphenyl)silane , Triisopropoxy(3-isopropenylphenyl)silane, Trimethoxy(2-isopropenylphenyl)silane, Triethoxy(2-isopropenylphenyl)silane, Tripropoxy(2-isopropenylphenyl)silane, Tributoxy(2-isopropenylphenyl)silane, Triisopropoxy(2-isopropenylphenyl)silane, Dimethoxymethyl (4-isopropenylphenyl)silane, diethoxymethyl(4-isopropenylphenyl)silane, dipropoxymethyl(4-isopropenylphenyl)silane, dibutoxymethyl(4-isopropenylphenyl)silane, diisopropoxymethyl(4-isopropenylphenyl)silane, dimethoxymethyl(3-isopropenylphenyl)silane, diethoxymethyl(3 -isopropenylphenyl)silane, dipropoxymethyl(3-isopropenylphenyl)silane, dibutoxymethyl(3-isopropenylphenyl)silane, diisopropoxymethyl(3-isopropenylphenyl)silane, dimethoxymethyl(2-isopropenylphenyl)silane, diethoxymethyl(2-isopropenylphenyl)silane, dipropoxymethyl(2-isopropenylphenyl) )silane, dibutoxymethyl(2-isopropenylphenyl)silane, diisopropoxymethyl(2-isopropenylphenyl)silane, dimethylmethoxy(4-isopropenylphenyl)silane, dimethylethoxy(4-isopropenylphenyl)silane, dimethylpropoxy(4-isopropenylphenyl)silane, dimethylbutoxy(4-isopropenylphenyl)silane , dimethylisopropoxy(4-isopropenylphenyl)silane, dimethylmethoxy(3-isopropenylphenyl)silane, dimethylethoxy(3-isopropenylphenyl)silane, dimethylpropoxy(3-isopropenylphenyl)silane, dimethylbutoxy(3-isopropenylphenyl)silane, dimethylisopropoxy(3-isopropenylphenyl)silane, dimethylmethoxy (2-isopropenylphenyl)silane, dimethylethoxy(2-isopropenylphenyl)silane, dimethylpropoxy(2-isopropenylphenyl)silane, dimethylbutoxy(2-isopropenylphenyl)silane, dimethylisopropoxy(2-isopropenylphenyl)silane, trichloro(4-vinylphenyl)silane, trichloro(3 -vinylphenyl)silane, trichloro(2-vinylphenyl)silane, tribromo(4-vinylphenyl)silane, tribromo(3-vinylphenyl)silane, tribromo(2-vinylphenyl)silane, dichloromethyl(4-vinylphenyl)silane, dichloromethyl(3-vinylphenyl) )silane, dichloromethyl(2-vinylphenyl)silane, dibromomethyl(4-vinylphenyl)silane, dibromomethyl(3-vinylphenyl)silane, dibromomethyl(2-vinylphenyl)silane, dimethylchloro(4-vinylphenyl)silane, dimethylchloro(3-vinylphenyl)silane , dimethylchloro(2-vinylphenyl)silane, dimethylbromo(4-vinylphenyl)silane, dimethylbromo(3-vinylphenyl)silane and dimethylbromo(2-vinylphenyl)silane.

Among these, preferred are trimethoxy(4-vinylphenyl)silane, triethoxy(4-vinylphenyl)silane, tripoxy(4-vinylphenyl)silane, tributoxy(4-vinylphenyl)silane, triisopropoxy(4-vinylphenyl)silane, trimethoxy(3-vinylphenyl) )silane, triethoxy(3-vinylphenyl)silane, tripropoxy(3-vinylphenyl)silane, tributoxy(3-vinylphenyl)silane, triisopropoxy(3-vinylphenyl)silane and trichloro(4-vinylphenyl)silane, and trimethoxy(4 -vinylphenyl)silane, triethoxy(4-vinylphenyl)silane, tripropoxy(4-vinylphenyl)silane, tributoxy(4-vinylphenyl)silane and triisopropoxy(4-vinylphenyl)silane.

[0073]

Examples of the branching agent represented by formula (2) include, but are not limited to, 1,1-bis(4-trimethoxysilylphenyl)ethylene, 1,1-bis(4-triethoxysilylphenyl)ethylene, 1,1-bis(4 -tripropoxysilylphenyl)ethylene, 1,1-bis(4-tripentoxysilylphenyl)ethylene, 1,1-bis(4-triisopropoxysilylphenyl)ethylene, 1,1-bis(3-trimethoxysilylphenyl)ethylene, 1,1-bis(3-triethoxysilylphenyl) )ethylene, 1,1-bis(3-tripropoxysilylphenyl)ethylene, 1,1-bis(3-tripentoxysilylphenyl)ethylene, 1,1-bis(3-triisopropoxysilylphenyl)ethylene, 1,1-bis(2-trimethoxysilylphenyl)ethylene , 1,1-bis(2-triethoxysilylphenyl)ethylene, 1,1-bis(3-tripropoxysilylphenyl)ethylene, 1,1-bis(2-tripentoxysilylphenyl)ethylene, 1,1-bis(2-triisopropoxysilylphenyl)ethylene, 1 ,1-bis(4-(dimethylmethoxysilyl)phenyl)ethylene, 1,1-bis(4-(diethylmethoxysilyl)phenyl)ethylene, 1,1-bis(4-(dipropylmethoxysilyl)phenyl)ethylene, 1,1-bis( 4-(dimethylethoxysilyl)phenyl)ethylene, 1,1-bis(4-(diethylethoxysilyl)phenyl)ethylene and 1,1-bis(4-(dipropylethoxysilyl)phenyl)ethylene.

Of these, preferred are 1,1-bis(4-trimethoxysilylphenyl)ethylene, 1,1-bis(4-triethoxysilylphenyl)ethylene, 1,1-bis(4-tripropoxysilylphenyl)ethylene, 1,1-bis(4-tripentoxysilylphenyl) )ethylene; and 1,1-bis(4-triisopropoxysilylphenyl)ethylene, and more preferably 1,1-bis(4-trimethoxysilylphenyl)ethylene.

[0074]

[Conjugated Diene-Based Polymer Production Method]

The method for producing a conjugated diene polymer of the present embodiment includes a polymerization/branching step of polymerizing at least a conjugated diene compound in the presence of an organolithium-based compound to obtain a conjugated diene-based polymer having a backbone branching structure, using, at least any one of the various branching agents described above. In one preferred aspect, the method includes the step of polymerizing a conjugated diene compound and an aromatic vinyl compound in the presence of an organolithium-based compound to obtain a copolymer, the step of reacting the copolymer and a vinyl-based monomer containing an alkoxysilyl group or a halosilyl group to obtain a branched backbone structure and a step of polymerizing a polymer chain having a backbone branching structure with at least a conjugated diene compound.

The production method of the conjugated diene based polymer of the present embodiment preferably includes a modification step of carrying out modification using a modifier containing a group containing a nitrogen atom.

The conjugated diene-based polymer contained in the modified conjugated diene-based polymer may be any one selected from a homopolymer of a single conjugated diene compound, a polymer namely a copolymer, various kinds of conjugated diene compounds, and a copolymer of a conjugated diene compound and an aromatic vinyl connections.

[0075]

(Polymerization/branching step)

In the polymerization/branching step of the conjugated diene polymer production method of the present embodiment, an organolithium-based compound such as an organolithium monolithium compound is used as a polymerization initiator to polymerize at least a conjugated diene compound, and a branching agent is added thereto to obtain a polymer based on a conjugated diene with a branching structure of the main chain.

In the polymerization step, the polymerization is preferably carried out using a growth reaction by a living anionic polymerization reaction, and thus a conjugated diene-based polymer containing an active end can be obtained. Thereafter, also in the branching step using the branching agent, branching of the main chain can be properly adjusted, and there is a tendency to be able to obtain a modified diene-based polymer having a high degree of modification by continuing polymerization at the active end after branching of the main chain.

[0076]

<Polymerization initiator>

An organolithium-based compound is used as the polymerization initiator, and at least an organolithium monolithium compound is preferably used.

Examples of the organo-monolithium compound include, but are not limited to, the organo-monolithium compound as a low molecular weight compound and the organo-monolithium compound as a solubilized oligomer.

Examples of the organolithium monolithium compound include, regarding the bonding method between an organic group and its lithium, a carbon-lithium bond-containing compound, a nitrogen-lithium bond-containing compound, and a tin-lithium bond-containing compound.

[0077]

The amount of the organolithium monolithium compound used as the polymerization initiator is preferably determined based on the molecular weight of the target conjugated diene polymer.

The ratio between the amount of monomer used, such as a conjugated diene compound, and the amount of polymerization initiator used is related to the degree of polymerization of the target conjugated diene-based polymer. In other words, there is a tendency to correlate it with number average molecular weight and/or weight average molecular weight.

Accordingly, in order to increase the molecular weight of the conjugated diene polymer, trimming can be made to reduce the amount of polymerization initiator, and trimming can be made to increase the amount of polymerization initiator in order to decrease the molecular weight.

[0078]

From the point of view of using the organolithium monolithium compound as one method of introducing a nitrogen atom into the conjugated diene polymer, it is preferably a substituted amino group-containing alkyl lithium compound or dialkylaminolithium.

In this case, a polymer based on a conjugated diene is obtained, containing at the polymerization initiating end the nitrogen atom of the amino group.

[0079]

The term "substituted amino group" refers to an amino group that does not contain an active hydrogen atom or has a structure in which the active hydrogen atom is protected.

Examples of the lithium alkyl compound containing an amino group not containing an active hydrogen atom include, but are not limited to, 3-dimethylaminopropyllithium, 3-diethylaminopropyllithium, 4-(methylpropylamino)butyllithium, and 4-hexamethyleneiminobutyllithium.

Examples of the lithium alkyl compound containing an amino group having a structure in which the active hydrogen atom is protected include, but are not limited to, 3-bistrimethylsilylaminopropyllithium and 4-trimethylsilylmethylaminobutyllithium.

[0080]

Examples of dialkylaminolithium include, but are not limited to, the following: lithium dimethylamide, lithium diethylamide, lithium dipropylamide, lithium dibutylamide, lithium di-n-hexylamide, lithium diheptylamide, lithium diisopropylamide, lithium dioctylamide, lithium di-2-ethylhexylamide, lithium didecylamide, ethylpropylamide lithium, lithium ethylbutylamide, lithium ethylbenzylamide, lithium methylphenethylamide, lithium hexamethyleneimide, lithium pyrrolidide, lithium piperidide, lithium heptamethyleneimide, lithium morpholide, 1-lithioazacyclooctane, 6-lithio-1,3,3-trimethyl-6-azabicyclo[3.2.1] octane and 1-lithio-1,2,3,6-tetrahydropyridine.

[0081]

Such an organolithium monolithium compound containing a substituted amino group can be reacted with a small amount of a polymerizable monomer such as 1,3-butadiene, isoprene or styrene to be used as the organolithium monolithium compound as an oligomer soluble in normal hexane or cyclohexane.

[0082]

From the viewpoint of industrial applicability and controllability of the polymerization reaction, the organolithium monolithium compound is preferably an alkyl lithium compound. In this case, a conjugated diene-based polymer containing an alkyl group at the polymerization-starting end can be obtained.

Examples of the lithium alkyl compound include, but are not limited to, n-butyl lithium, sec-butyl lithium, t-butyl lithium, n-hexyl lithium, benzyl lithium, phenyl lithium, and stilben lithium.

From the viewpoint of industrial applicability and controllability of the polymerization reaction, the lithium alkyl compound is preferably n-butyl lithium or sec-butyl lithium.

[0083]

One of these organolithium monolithium compounds may be used individually, or two or more of them may be used together. Alternatively, another organometallic compound may be used together.

Examples of such other organometallic compound include alkaline earth metal compounds, other alkali metal compounds, and other organometallic compounds.

Examples of alkaline earth metal compounds include, but are not limited to, organomagnesium compounds, organocalcium compounds, and organostrontium compounds. Other examples include compounds of alkoxides, sulfonates, carbonates and amides of alkaline earth metals.

Examples of organomagnesium compounds include dibutyl magnesium and ethyl butyl magnesium. Examples of other organometallic compounds include organoaluminum compounds.

[0084]

Examples of the polymerization reaction method used in the polymerization step include, but are not limited to, batch and continuous types of polymerization reaction.

In the continuous type, one reactor or two or more connected reactors can be used. As the reactor for the continuous type, for example, a vessel or tubular reactor provided with a stirrer can be used. In the continuous type, a monomer, an inert solvent, and a polymerization initiator are continuously fed into the reactor, a polymer solution containing a polymer is produced in the reactor, and the polymer solution is continuously discharged.

As the reactor for the batch type, for example, a vessel reactor equipped with a stirrer is used. In the batch type, it is preferable to feed monomer, inert solvent and polymerization initiator into the reactor, optionally continuous or intermittent additional supply of monomer during polymerization, obtain a polymer solution containing polymer in the reactor, and discharge the polymer solution after completion of polymerization.

In the process for producing a conjugated diene based polymer of the present embodiment, in order to produce a conjugated diene based polymer having a high proportion of active end, it is preferable to use a continuous type in which the polymer is continuously discharged to be fed to the subsequent reaction in a short period of time.

[0085]

In the polymerization step for the conjugated diene based polymer, the polymerization is preferably carried out in an inert solvent.

Examples of the inert solvent include hydrocarbon-based solvents such as saturated hydrocarbons and aromatic hydrocarbons. Specific examples of the hydrocarbon-based solvent include, but are not limited to, aliphatic hydrocarbons such as butane, pentane, hexane, and heptane; alicyclic hydrocarbons such as cyclopentane, cyclohexane, methylcyclopentane and methylcyclohexane; aromatic hydrocarbons such as benzene, toluene and xylene; and a hydrocarbon containing a mixture of any of them.

Prior to supplying the solvent to the polymerization reaction, allene and acetylene impurities are preferably treated using an organometallic compound, since thus a polymer based on a conjugated diene having a high concentration of an active end tends to be obtained, and a polymer based on conjugated diene, characterized by a high degree of modification.

[0086]

A polar compound may be added during the polymerization step. Thus, an aromatic vinyl compound can be randomly polymerized with a conjugated diene compound. There is a trend towards the possibility of using a polar compound also as a vinylating agent to control the microstructure of the conjugated diene site. In addition to this, it tends to be effective, for example, to speed up the polymerization reaction.

[0087]

Examples of the polar compound include, but are not limited to, 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-oxolanyl)propane; tertiary amine compounds such as tetramethylethylenediamine, dipiperidinoethane, trimethylamine, triethylamine, pyridine and quinuclidine; alkali metal alkoxide compounds such as potassium t-amylate, potassium t-butoxide, sodium t-butoxide and sodium amylate; and phosphine compounds such as triphenylphosphine.

One of these polar compounds may be used individually, or two or more of them may be used together.

[0088]

The amount of the polar compound to be used is not particularly limited, but may be selected according to the purpose and the like, and is preferably in the range of 0.01 mol or more to 100 mol or less based on one mol of the polymerization initiator.

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

There is a tendency for a plurality of polar compounds to simultaneously exhibit an effective randomizing effect in the copolymerization of a conjugated diene compound and an aromatic vinyl compound and to be able to be used as a modifier for aromatic vinyl compound distribution and styrene block size.

As a method for randomizing a conjugated diene compound and an aromatic vinyl compound, for example, the method according to the specification of Japanese Patent Laid-Open No. 59-140211 in which the copolymerization reaction is started under the condition that all of styrene and part of 1,3-butadiene is present can be used. , and the remainder of 1,3-butadiene is intermittently added during the copolymerization reaction.

In the polymerization/branching step in the conjugated diene-based polymer production method of the present embodiment, when adding 1,3-butadiene sectionally, the remaining amount of 1,3-butadiene added sectionally is not particularly limited, and from the viewpoint of improving the degree of modification, it is preferably 1% and more than the total amount of 1,3-butadiene. From the viewpoint of improving heat resistance, this amount is preferably less than 20%, more preferably less than 15%, and furthermore preferably less than 10%. When the dissected addition of 1,3-butadiene falls within this range, there is a tendency for the distance between branching points in the main chain branching structure to decrease, and thus the kneading viscosity decreases, which suppresses heat generation, and improves heat resistance.

[0089]

In the polymerization step, the polymerization temperature is preferably the temperature at which the living anionic polymerization proceeds, which is more preferably 0° C. or more and more preferably 120° C. or less in terms of productivity. For the case where the polymerization temperature falls within this range, there is a tendency for the active end-reacting modifier to be able to sufficiently reach the reaction rate after completion of the reaction. The polymerization temperature is furthermore preferably in the range of 50°C or more to 100°C or less.

[0090]

In the conjugated diene-based polymer production method of the present embodiment, the amount of the branching agent added in the branching step to obtain the main chain branching structure is not particularly limited, but can be selected according to the purpose and the like, and is preferably in the range of 0, 03 mol or more to 0.5 mol or less, more preferably 0.05 mol or more to 0.4 mol or less, and further preferably 0.01 mol or more to 0.25 mol or less, when calculated per mol of polymerization initiator.

The branching agent can be used in an appropriate amount according to the number of branching points of the main chain branching structure of the conjugated diene portion of the conjugated diene-based target polymer.

[0091]

In the branching step, the timing for adding the branching agent is not particularly limited, but may be selected according to the purpose and the like, and from the viewpoints of improving the absolute molecular weight of the conjugated diene-based polymer and improving the degree of modification, is the timing after adding the polymerization initiator by the time conversion ratio of the raw material, preferably 20% or more, more preferably 40% or more, furthermore preferably 50% or more, furthermore preferably 65% or more, and still much more, preferably 75% and more.

After the branching agent is added, the desired feedstock may be further added to continue the polymerization step after branching, or the above process may be repeated.

The amount of monomer added additionally is not particularly limited, and from the viewpoint of improving the degree of modification of the conjugated diene-based polymer, it is preferably 5% or more, more preferably 10% or more, furthermore preferably 15% or more, furthermore preferably 20 % or more, and, moreover, to a much greater extent, preferably 25% or more, when calculating the total amount of conjugated diene-based monomers, for example, the total amount of butadiene used in the polymerization stage.

[0092]

The conjugated diene-based polymer obtained up to the modification reaction step by using the polymerization/branching step in the conjugated diene-based polymer production method of the present embodiment has a Mooney viscosity measured at 110° C., preferably in the range of 10 or more to 150 or less, more preferably 15 or more to 140 or less, and furthermore preferably 20 or more to 130 or less.

When the Mooney viscosity falls within this range, the conjugated diene-based polymer of the present embodiment tends to exhibit excellent processability and abrasion resistance.

[0093]

The amount of bound conjugated diene in the conjugated diene based polymer of the present embodiment is not particularly limited, and is preferably 40% (mass) or more to 100% (mass) or less, and more preferably 55% (mass) and more to 80% (wt.) and less.

In addition, the amount of bound aromatic vinyl compound in the conjugated diene-based polymer of the present embodiment is not particularly limited, and according to the above description of the invention, it is preferably 1% (mass) or more, and more preferably 10% (mass), and more. The upper limit is not particularly limited, and is preferably less than 60% (mass.) in accordance with the above description of the invention.

In this case, the amount of bound aromatic vinyl compound can be measured according to the UV absorption of the phenyl group, and based on the value thus obtained, the amount of bound conjugated diene can also be obtained. Specifically, these quantities are measured in accordance with the method described below in the examples.

[0094]

In the conjugated diene-based polymer of the present embodiment, the amount of bound vinyl in the unit unit of the conjugated diene is not particularly limited, and is preferably 10% (mol) or more to 75% (mol) or less, and more preferably 20 % (mol.) or more to 65% (mol.) or less.

When the amount of bonded vinyl falls within the range described above, the balance between low hysteresis loss performance and wet skid resistance, abrasion resistance and fracture toughness obtained when the material is in the form of a vulcanizate, tends to be more excellent.

In this case, in the presence of a modified diene-based polymer in the form of a copolymer of butadiene and styrene, the amount of bound vinyl (amount of 1,2-bond) in the butadiene unit unit can be obtained using the Hampton method (R. R. Hampton, Analytical Chemistry, 21, 923 ( 1949)). Specifically, it can be measured using the method described below in the examples.

[0095]

With regard to the microstructure of the conjugated diene based polymer, when the amounts of the above bonds in the conjugated diene based polymer of the present embodiment respectively fall within the above-described ranges and the glass transition temperature of the conjugated diene based polymer is in the range of −45° C. or more to - 15° C. or less, there is a tendency to be able to obtain a vulcanizate characterized by a more excellent balance between low hysteresis loss characteristics and wet skid resistance.

The glass transition temperature is defined as the tip of the peak (inflection point) of the differential DSC curve obtained by recording the DSC curve during temperature increase over a prescribed temperature range in accordance with ISO 22768:2006. Specifically, it can be measured using the method described below in the examples.

[0096]

When the conjugated diene-based polymer of the present embodiment is in the form of a conjugated diene-aromatic vinyl compound copolymer, from the viewpoint of improving fuel efficiency alone, an increased fraction of aromatic vinyl compound unit unit is preferable.

Specifically, in the case of a styrene-butadiene copolymer, when the copolymer is decomposed using the ozonolysis method known as the method from Tanaka et al. (Polymer, 22, 1721 (1981)), for the analysis of the distribution of styrene chains using the GPC method, the amount of isolated styrene, calculated on the total amount of bound styrene, is 40% (wt.) or more, and the amount of the structure of styrene linked in a chain , consisting of 8 or more elementary units connected in a chain of styrene, amounting to 5.0% (wt.) or less.

In this case, the resulting vulcanized rubber especially tends to exhibit excellent low hysteresis loss characteristics.

[0097]

(modification stage)

In the production method of the conjugated diene based polymer of the present embodiment, the modification step is preferably carried out in the form of modifying the conjugated diene based polymer obtained by carrying out the polymerization/branching step using a modifier containing a group containing a nitrogen atom.

In the modification step, the modification reaction of at least one of the active ends of the conjugated diene-based polymer is carried out using a nitrogen atom-containing group to obtain a modified conjugated diene-based polymer.

[0098]

<Modifier>

Examples of the modifier include, but are not limited to, tris(3-trimethoxysilylpropyl)amine, tris(3-triethoxysilylpropyl)amine, tris(3-tripropoxysilylpropyl)amine, bis(3-trimethoxysilylpropyl)-[3-(2,2- dimethoxy-1-aza-2-silacyclopentane)propyl]amine, tetrakis(3-trimethoxysilylpropyl)-1,3-propanediamine, tris(3-trimethoxysilylpropyl)-[3-(1-methoxy-2-trimethylsilyl-1-sila- 2-azacyclopentane)propyl]-1,3-propanediamine, tris(3-trimethoxysilylpropyl)-[3-(1-methoxy-2-methyl-1-sila-2-azacyclopentane)propyl]-1,3-propanediamine, bis (3-triethoxysilylpropyl)-[3-(2,2-diethoxy-1-aza-2-silacyclopentane)propyl]-[3-(1-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-hexamethylenediamine, pentakis(3-trimethoxysilylpropyl)diethylenetriamine, tris(3-trimethoxysilylpropyl)methyl-1,3-propanediamine, tetrakis[3-(2,2-dimethoxy-1 -aza-2-silacyclopentane)propyl]silane, bis(3-trimethoxysilylpropyl)bis[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]silane, tris[3-(2,2-dimethoxy -1-aza-2-silacyclopentane)propyl]-(3-trimethoxysilylpropyl)silane, tris[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]-[3-(1-methoxy-1 -trimethylsilyl-1-sila-2-azacyclopentane)propyl]silane, 3-tris[2-(2,2-dimethoxy-1-aza-2-silacyclopentane)ethoxy]silyl-1-trimoxysilylpropane, 1-[3-( 1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane)propyl]-3,4,5-tris(3-trimethoxysilylpropyl)cyclohexane, 1-[3-(2,2-dimethoxy-1-aza-2 -silacyclopentane)propyl]-3,4,5-tris(3-trimethoxysilylpropyl)cyclohexane, 3,4,5-tris(3-trimethoxysilylpropyl)cyclohexyl[3-(2,2-dimethoxy-1-aza-2-silacyclopentane )propyl] ether, (3-trimethoxysilylpropyl)phosphate, bis(3-trimethoxysilylpropyl)-[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]phosphate, bis[3-(2,2 -dimethoxy-1-aza-2-silacyclopentane)propyl]-(3-trimethoxysilylpropyl)phosphate; and tris[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]phosphate.

[0099]

The modifier used in the modification step preferably includes a compound represented by any one of the following general formulas (A) to (C):

[0100]

, (А)

, (A)

[0101]

where each R ¹ to R ⁴ independently represents an alkyl group containing from 1 to 20 carbon atoms, or an aryl group containing from 6 to 20 carbon atoms, R ⁵ represents an alkylene group containing from 1 to 10 carbon atoms, and R ⁶ is an alkylene group containing from 1 to 20 carbon atoms; and m is an integer of 1 or 2, n is an integer of 2 or 3, (m+n) is an integer of 4 or more, and each R ¹ to R ⁴ when plural is, respectively, independent;

[0102]

, (B)

, (B)

[0103]

where each R ¹ to R ⁶ independently represents an alkyl group containing from 1 to 20 carbon atoms, or an aryl group containing from 6 to 20 carbon atoms, and each from R ⁷ to R ⁹ independently represents an alkylene group containing from 1 to 20 carbon atoms; and each m, n and l is independently an integer in the range of 1 to 3, (m+n+l) is an integer of 4 or more, and each R ¹ to R ⁶ when plural is, accordingly, independent;

[0104]

, (C)

, (C)

[0105]

where each R ¹² to R ¹⁴ independently represents a single bond or an alkylene group containing from 1 to 20 carbon atoms, each from R ¹⁵ to R ¹⁸ and R ²⁰ independently represents an alkyl group containing from 1 to 20 carbon atoms, each of R ¹⁹ and R ²² is independently an alkylene group having 1 to 20 carbon atoms, R ²¹ is an alkyl group or a trialkylsilyl group having 1 to 20 carbon atoms; m is an integer ranging from 1 to 3 and p is 1 or 2; each R ¹² to R ²² , m and p, if present in the plural, are respectively independent and may be identical to or different from the others; i is an integer in the range of 0 to 6, j is an integer in the range of 0 to 6, k is an integer in the range of 0 to 6, (i+j+k) is an integer in the range of 4 to 10; and A is a hydrocarbon group containing 1 to 20 carbon atoms, or an organic group containing 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 containing no active hydrogen atom.

[0106]

Examples of the modifier described by formula (A) include, but are not limited to, 2,2-dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza-2-silacyclopentane, 2,2-diethoxy-1-(3 -triethoxysilylpropyl)-1-aza-2-silacyclopentane, 2,2-dimethoxy-1-(4-trimethoxysilylbutyl)-1-aza-2-silacyclohexane, 2,2-dimethoxy-1-(5-trimethoxysilylpentyl) -1- aza-2-silacycloheptane, 2,2-dimethoxy-1-(3-dimethoxymethylsilylpropyl)-1-aza-2-silacyclopentane, 2,2-diethoxy-1-(3-diethoxyethylsilylpropyl)-1-aza-2-silacyclopentane, 2-methoxy-2-methyl-1-(3-trimethoxysilylpropyl)-1-aza-2-silacyclopentane, 2-ethoxy-2-ethyl-1-(3-triethoxysilylpropyl)-1-aza-2-silacyclopentane, 2- methoxy-1-methyl-1-(3-dimethoxymethylsilylpropyl)-1-aza-2-silacyclopentane; and 2-ethoxy-2-ethyl-1-(3-diethoxyethylsilylpropyl)-1-aza-2-silacyclopentane.

From the point of view of reactivity and the ability of interaction between the functional group of the modifier and the inorganic filler such as silicon dioxide, and from the point of view of processability among them, the options with equal m 2 and equal n 3 are preferred. Specifically, 2,2- dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza-2-silacyclopentane; and 2,2-diethoxy-1-(3-triethoxysilylpropyl)-1-aza-2-silacyclopentane.

[0107]

The reaction temperature, reaction time, and the like while promoting the reaction between the modifier described by the formula (A) and the active end of the polymer are not particularly limited, and it is preferable to carry out the reaction at a temperature of 0°C or more to 120°C or less. for 30 seconds or more.

The total number of moles of the alkoxy group associated with the silyl group of the compound used as the modifier described by formula (A) preferably corresponds to the number of moles of the alkali metal compound and/or the alkaline earth metal compound of the polymerization initiator added, with a multiplicity preferably ranging from 0.6 and more to 3.0 or less, more preferably 0.8 or more to 2.5 or less, and further preferably 0.8 or more to 2.0 or less. From the viewpoint of showing the modified conjugated diene-based polymer thus obtained to have a sufficient degree of modification and molecular weight and to have a branched structure, the aforementioned fold for a given total number of moles is preferably 0.6 or more, and a branched polymer component is preferably obtained coupling reaction for polymer ends to improve processability, and, in addition, from the point of view of the cost of the modifier, the aforementioned fold matching for a given total number of moles is preferably 3.0 or less.

A more specific number of moles of the polymerization initiator corresponds to the number of moles of the modifier with a multiple of preferably 3.0 or more, and more preferably 4.0 or more.

[0108]

Examples of the modifier described by formula (B) include, but are not limited to, tris(3-trimethoxysilylpropyl)amine, tris(3-methyldimethoxysilylpropyl)amine, tris(3-triethoxysilylpropyl)amine, tris(3-methyldiethoxysilylpropyl)amine, tris(trimethoxysilylmethyl)amine, tris(2-trimethoxysilylethyl)amine and tris(4-trimethoxysilylbutyl)amine.

From the point of view of reactivity and the ability of interaction between the functional group of the modifier and the inorganic filler such as silicon dioxide, and from the point of view of processability among them, options are preferred when all of n, m and l 3 are preferred. Specific preferred examples include tris(3 -trimethoxysilylpropyl)amine; and tris(3-triethoxysilylpropyl)amine.

[0109]

The reaction temperature, reaction time, and the like while promoting the reaction between the modifier described by the formula (B) and the active end of the polymer are not particularly limited, and it is preferable to carry out the reaction at a temperature of 0°C or more to 120°C or less. for 30 seconds or more.

The total number of moles of the alkoxy group associated with the silyl group of the compound used as the modifier described by formula (B) corresponds to the number of moles of lithium contained in the added polymerization initiator, with a multiplicity in the range preferably from 0.6 or more to 3.0 or less, more preferably 0.8 or more to 2.5 or less, and further preferably 0.8 or more to 2.0 or less. From the viewpoint of showing the modified conjugated diene-based polymer to have sufficient degree of modification and molecular weight and to have a branched structure, the aforementioned fold for a given total number of moles is preferably 0.6 or more, and the branched polymer component is preferably obtained by a coupling reaction for ends of the polymer in order to improve processability, and, in addition, from the point of view of the cost of the modifier, the aforementioned fold fit for a given total number of moles is preferably 3.0 or less.

A more specific number of moles of the polymerization initiator corresponds to the number of moles of the modifier with a multiple of preferably 4.0 or more, and more preferably 5.0 or more.

[0110]

In formula (C), A is preferably described by any one of the following general formulas from (II) and (V):

[0111]

, (II)

, (II)

[0112]

where In ¹ represents a single bond or a hydrocarbon group containing from 1 to 20 carbon atoms, and represents an integer in the range from 1 to 10, and In ¹ when present in the plural is, respectively, independent;

[0113]

, (III)

, (III)

[0114]

where B ² represents a single bond or a hydrocarbon group containing from 1 to 20 carbon atoms, B ³ represents an alkyl group containing from 1 to 20 carbon atoms, and represents an integer in the range from 1 to 10, and each of B ² and B ³ when present in the plural is, respectively, independent;

[0115]

,(IV)

,(IV)

[0116]

where B ⁴ represents a single bond or a hydrocarbon group containing from 1 to 20 carbon atoms, and represents an integer in the range from 1 to 10, and B ⁴ when present in the plural is, respectively, independent; And

[0117]

, (V)

, (V)

[0118]

where B ⁵ represents a single bond or a hydrocarbon group containing from 1 to 20 carbon atoms, a represents an integer in the range from 1 to 10, and B ⁵ when present in the plural is, respectively, independent.

[0119]

Examples of the modifier represented by formula (C) where A is represented by formula (II) include, but are not limited to, 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-triethoxysilylpropyl)amine, bis(3-triethoxysilylpropyl)-[3-(2,2-diethoxy-1-aza-2-silacyclopentane)propyl] amine, bis[3-(2,2-diethoxy-1-aza-2-silacyclopentane)propyl]-(3-triethoxysilylpropyl)amine, tris[3-(2,2-diethoxy-1-aza-2-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, tetrakis(3-triethoxysilylpropyl)-1,3-propanediamine, tris (3-triethoxysilylpropyl)-[3-(2,2-diethoxy-1-aza-2-silacyclopentane)propyl]-1,3-bisaminomethylcyclohexane, bis(3-trimethoxysilylpropyl)bis[3-(2,2-diethoxy- 1-aza-2-silacyclopentane)propyl]-1,3-bisaminomethylcyclohexane, tris[3-(2,2-diethoxy-1-aza-2-silacyclopentane)propyl]-(3-triethoxysilylpropyl)-1,3-propanediamine , tetrakis[3-(2,2-diethoxy-1-aza-2-silacyclopentane)propyl]-1,3-propanediamine, tris(3-triethoxysilylpropyl)-[3-(1-ethoxy-2-trimethylsilyl-1- sila-2-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, tetrakis(3-methoxysilylpropyl)-1,6-hexamethylenediamine and pentakis(3-trimethoxysilylpropyl)diethylenetriamine .

[0120]

Examples of the modifier described by formula (C), where A is described by formula (III), include the following, but are not limited to: 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, N ¹ ,N ^1' - (propan-1,3-diyl) bis (N ¹ -methyl-N ³ , N ³ -bis (3- (trimethoxysilyl) propyl-1,3-propanediamine) and N ¹ - (3- (bis (3- (trimethoxysilyl)propyl)amino)propyl)-N ¹ -methyl-N ³ -(3-(methyl (3-(trimethoxysilyl)propyl)amino)propyl)-N ³ -(3-(trimethoxysilyl)propyl)-1, 3-propanediamine.

[0121]

Examples of the modifier represented by formula (C) where A is represented by formula (IV) include, but are not limited to, tetrakis[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]silane, tris [3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]-(3-trimethoxysilylpropyl)silane, tris[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]- [3-(1-Methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane)propyl]silane, bis(3-trimethoxysilylpropyl)bis[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl ]silane, (3-trimethoxysilyl)-[3-(1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane)bis[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl] silane, bis[3-(1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane)bis[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]silane, tris(3- trimethoxysilylpropyl)-[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]silane, bis(3-trimethoxysilylpropyl)-[3-(1-methoxy-2-trimethylsilyl-1-sila-2- azacyclopentane)propyl]-[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]silane, bis[3-(1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane)propyl] bis(3-trimethoxysilylpropyl)silane; and bis(3-trimethoxysilylpropyl)bis[3-(1-methoxy-2-methyl-1-sila-2-azacyclopentane)propyl]silane.

[0122]

Examples of the modifier represented by formula (C) where A is represented by formula (V) include, but are not limited to, 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.

[0123]

In formula (C), A is preferably described by formula (II) or formula (III), and k is 0 (zero).

Such a modifier tends to be readily available and tends to form the resulting conjugated diene polymer of the present embodiment, showing more excellent abrasion resistance and low hysteresis loss characteristics when the material is in the form of a vulcanizate.

Examples of such a modifier include, but are not limited to, 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-(2,2- dimethoxy-1-aza-2-silacyclopentane)propyl]-1,3-propanediamine, tetrakis(3-trimethoxysilylpropyl)-1,3-propanediamine, tetrakis(3-trimethoxysilylpropyl)-1,3-bisaminomethylcyclohexane, tris(3-trimethoxysilylpropyl) )methyl-1,3-propanediamine; and bis[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]-(3-trimethoxysilylpropyl)methyl-1,3-propanediamine.

[0124]

In formula (C), description of A by formula (II) or formula (III) and k 0 (zero) and representing a as an integer in the range of 2 to 10 in formula (II) or formula (III) are more preferable.

Thus, abrasion resistance and low hysteresis loss characteristics when the material is in the form of a vulcanizate tend to be more excellent.

Examples of such a modifier include, but are not limited to, tetrakis[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]-1,3-propanediamine, tetrakis(3-trimethoxysilylpropyl)-1,3 -propanediamine, tetrakis(3-trimethoxysilylpropyl)-1,3-bisaminomethylcyclohexane and N ¹ -(3-(bis(3-(trimethoxysilyl)propyl)amino)propyl)-N ¹ -methyl-N ³ -(3-(methyl (3-(trimethoxysilyl)propyl)amino)propyl)-N ³ -(3-(trimethoxysilyl)propyl)-1,3-propanediamine.

[0125]

The amount of the compound represented by formula (C) added as a modifier can be adjusted to promote the reaction between the modifier and the conjugated diene polymer so that the moles of modifier relative to the moles of conjugated diene polymer can be as desired. stoichiometric ratio and thus tends to achieve the desired branched star polymer structure.

Specifically, the number of moles of the conjugated diene polymer corresponds to the number of moles of the modifier with a multiple of preferably 5.0 or more, and more preferably 6.0 or more.

Here, in the formula (C), the number of functional groups ((m - 1) × i+p × j+k) of the modifier is preferably an integer in the range of 5 to 10, and more preferably an integer in the range of 6 to 10 .

[0126]

In the modified conjugated diene-based polymer of the present embodiment, the proportion of the polymer containing modifying groups in the conjugated diene-based polymer is expressed as the degree of modification.

In the conjugated diene-based polymer of the present embodiment, the degree of modification is preferably 60% (mass) or more, more preferably 65% (mass) or more, moreover, preferably 70% (mass) or more, moreover still, preferably 75% (wt.) or more, moreover to a much greater extent, preferably 80% (wt.) or more, and particularly preferably 82% (wt.) or more.

For the case of the degree of modification of 60% (mass.) or more, there is a tendency to achieve excellent processability obtained when using the material to obtain a vulcanizate, and more excellent abrasion resistance and low hysteresis loss characteristics when the material is in the form vulcanizate.

[0127]

In the present embodiment, after the modification step or before the modification step, a condensation reaction step may be carried out in the form of carrying out a condensation reaction in the presence of a condensation accelerator.

[0128]

The conjugated diene-based polymer of the present embodiment may be hydrogenated at its conjugated diene site.

The method for hydrogenating the conjugated diene portion of the modified conjugated diene based polymer of the present embodiment is not particularly limited, and any known method can be used.

As one suitable hydrogenation method, a method in which hydrogenation is carried out by blowing hydrogen gas into the polymer solution in the presence of a catalyst can be used.

Examples of the catalyst include heterogeneous catalysts such as a noble metal catalyst supported on a porous inorganic support; and homogeneous catalysts such as a catalyst obtained by reacting a solubilized nickel, cobalt and solubilized salt with an organoaluminum compound and the like, and a catalyst using a metallocene such as a titanocene. From the viewpoint of being able to select mild hydrogenation conditions, a titanocene catalyst is preferably used among these catalysts.

In addition, the hydrogenation of an aromatic group can be carried out using a supported noble metal catalyst.

[0129]

Examples of the hydrogenation catalyst include, but are not limited to: (1) a supported heterogeneous hydrogenation catalyst obtained by supporting a metal such as Ni, Pt, Pd, or Ru on a carbon, silica, alumina, or diatomite, (2) what is called a Ziegler catalyst using a salt derived from an organic acid and Ni, Co, Fe, Cr and the like, or a transition metal salt such as an acetylacetone salt and a reducing agent such as an organoaluminum compound, and (3) what is called an organometallic complex, such as an organometallic compound of Ti, Ru, Rh, or Zr. In addition, examples of the hydrogenation catalyst include known hydrogenation catalysts described in, for example, 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 Laid-Open No. 8-109219. One preferred hydrogenation catalyst is a reaction mixture of a titanocene compound and a reducing organometallic compound.

[0130]

In the conjugated diene polymer production method of the present embodiment, if necessary, a deactivator, a neutralizer, and the like can be added to the resulting polymer solution after the reaction step.

Examples of the deactivator include, but are not limited to, water; and alcohols such as methanol, ethanol and isopropanol.

Examples of the neutralizer include, but are not limited to, carboxylic acids such as stearic acid, oleic acid, and versatic acid (a mixture of highly branched carboxylic acids having 9 to 11 carbon atoms, mostly 10 carbon atoms); and an inorganic acid aqueous solution and carbon dioxide gas.

[0131]

From the viewpoint of preventing gelation after polymerization and improving processing stability, a rubber stabilizer is preferably added to the conjugated diene-based polymer of the present embodiment.

As a rubber stabilizer, any known stabilizer may be used, not limited to the following, and preferred examples include antioxidants such as 2,6-di-tert-butyl-4-hydroxytoluene (BHT), n-octadecyl-3-(4 '-hydroxy-3',5'-di-tert-butylphenol)propionate; and 2-methyl-4,6-bis[(octylthio)methyl]phenol.

[0132]

[Conjugated diene oil-filled polymer]

The conjugated diene oil-extended copolymer of the present embodiment contains the conjugated diene-based polymer of the present embodiment described above and the extender oil.

Thus, the processability of the conjugated diene-based polymer can be further improved.

One preferred example of a method for adding an extender oil to a conjugated diene based polymer includes, but is not limited to, a method in which an extender oil is added to an admixture solution of the conjugated diene based polymer and the solvent is removed from the resulting filled polymer solution.

Examples of the extender oil include aromatic oil, naphthenic oil, and paraffin oil. From the point of view of environmental safety, prevention of oil bleeding, and wet grip performance, among these oils, an oil alternative to aromatic oil and containing 3% (wt.) or less of a polycyclic aromatic component (PCA) that complies with the IP document is preferred among these oils. 346. Examples of oil alternative to aromatic oil include TDAE (purified distilled aromatic extracts), MES (low extraction solvate) and the like as mentioned in Kautschuk Gummi Kunststoffe 52 (12) 799 (1999), and RAE (residual aromatic extracts). ).

The amount of extender oil added is in the range of 1 to 60 parts by mass, preferably 10 to 60 parts by mass, and more preferably 15 to 37.5 mass parts, based on 100 mass parts of the conjugated diene based polymer of the present embodiment.

[0133]

(Solvent removal step)

As a method for producing the conjugated diene-based polymer of the present embodiment from the polymer solution, any of the known methods can be used. Examples of the method include a method in which the conjugated diene-based polymer is filtered after the solvent is separated by stripping or the like, and the resulting product is dehydrated and dried to obtain a conjugated diene-based polymer, a method in which the solution is concentrated in a washing tank, and the resulting product is devolatilized by using a curved extruder and the like, and a method in which the solution is directly devolatilized by using a drum dryer and the like.

[0134]

[Rubber Composition]

The rubber composition of the present embodiment contains a rubber component and 5.0 mass parts or more to 150 mass parts or less of a filler based on 100 mass parts of the rubber component.

From the viewpoints of fuel efficiency performance, processability, and improvement in abrasion resistance, the rubber component contains, based on the total amount (100% (mass.)) of the rubber component, 10% (mass.) or more of the above-described conjugated diene-based polymer of the present embodiment or the conjugated diene-based oil-extended polymer of the present embodiment.

[0135]

The filler preferably comprises an inorganic silica filler.

For the case of dispersing the silica-based inorganic filler in the rubber composition of the present embodiment, the rubber composition tends to show more excellent processability obtained by using the material to produce a vulcanizate, and tends to show a more excellent balance between low loss per hysteresis and wet skid resistance, abrasion resistance and fracture strength when the material is in the form of a vulcanizate.

Also, if the rubber composition of the present embodiment is to be used in an application for a vulcanized rubber such as a tire, a vehicle component such as an anti-vibration rubber, or footwear, a silica-based inorganic filler is preferably contained.

[0136]

The rubber composition of the present embodiment, in combination with the conjugated diene-based polymer of the present embodiment, may contain a rubber-like polymer other than the conjugated diene-based polymer of the present embodiment (hereinafter, simply referred to as "rubber-like polymer").

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

Specific examples of the rubbery polymer include, but are not limited to, butadiene rubber or a hydrogenated product thereof, isoprene rubber or a hydrogenated product thereof, styrene-based elastomers such as styrene-butadiene rubber or a hydrogenated product thereof, and a styrene-butadiene block copolymer or a hydrogenated product thereof, a styrene-isoprene block copolymer or a hydrogenated product thereof, and acrylonitrile butadiene rubber or a hydrogenated product thereof.

[0137]

Examples of the non-diene based polymer include, but are not limited to, the following: olefin based elastomers such as ethylene propylene rubber, ethylene propylene diene rubber, ethylene butene diene rubber, ethylene butene rubber, ethylene hexene rubber and ethylene-octene rubber, butyl rubber, brominated butyl rubber, acrylic rubber, fluorine rubber, silicone rubber, chlorinated polyethylene rubber, epichlorohydrin rubber, α,β-unsaturated nitrile-acrylic acid-conjugated diene copolymer rubber, urethane rubber and polysulfide rubber.

[0138]

Examples of natural rubber include, but are not limited to, smoked sheet RSS (grooved smoked sheet) No. 3 to 5, SMR (standard Malaysian rubber) and epoxidized natural rubber.

[0139]

The various rubber-like polymers described above may be in the form of a modified rubber imbued with a polarity-characterizing functional group such as a hydroxyl group or an amino group. For use in the tire, butadiene rubber, isoprene rubber, styrene-butadiene rubber, natural rubber and butyl rubber are preferably used.

[0140]

From the point of view of the balance between performance and processability, the weight average molecular weight of the rubbery polymer is preferably 2,000 or more to 2,000,000 or less, and more preferably 5,000 or more to 1,500,000 or less. In addition, a rubbery polymer having a low molecular weight, namely what is called liquid rubber, can be used. One of these rubbery polymers may be used individually, or two or more of them may be used together.

[0141]

In the rubber composition containing the conjugated diene-based polymer of the present embodiment and the rubber-like polymer, the ratio between the content levels (when expressed as a weight ratio) of the conjugated diene-based polymer of the present embodiment and the rubber-like polymer in relation to the ratio (conjugated diene-based polymer of the present embodiment embodiment/rubber-like polymer) is preferably 10/90 or more to 100/0 or less, more preferably 20/80 or more to 90/10 or less, and further preferably 50/50 or more to 80/20 or less.

Accordingly, the rubber component contained in the rubber composition contains, based on the total amount (100 mass parts) of the rubber component, the conjugated diene-based polymer of the present embodiment in an amount in the range of preferably 10 mass parts or more to 100 mass parts, and less, more preferably 20 mass parts or more to 90 mass parts or less, and further preferably 50 mass parts or more to 80 mass parts or less.

When the ratio between the levels (conjugated diene-based polymer of the present embodiment/rubber-like polymer) falls within the above-described range, the balance between low hysteresis loss characteristics and wet skid resistance and abrasion resistance obtained when the material is in the form of a vulcanizate is excellent. and also excellent is the fracture toughness.

[0142]

Examples of the filler contained in the rubber composition of the present embodiment include, but are not limited to, silica inorganic filler, carbon black, metal oxide, and metal hydroxide. Among them, an inorganic filler based on silica is preferred.

One of these excipients may be used individually, or two or more of them may be used together.

[0143]

The filler level in the rubber composition of the present embodiment is in the range of 5.0 mass parts or more to 150 mass parts or less, preferably 20 mass parts or more to 100 mass parts or less, and further preferably 30 mass parts or less. parts or more to 90 mass parts or less, based on 100 mass parts of the rubber component containing the conjugated diene-based polymer of the present embodiment.

From the point of view of demonstrating the effect of adding a filler, the filler level is 5.0 mass parts or more, and from the point of view of sufficient dispersion of the filler to achieve sufficient processability and mechanical strength of the rubber composition in practice, this level is 150 mass parts or less.

[0144]

The silica-based inorganic filler is not particularly limited, any known filler can be used, a solid particle containing SiO ₂ or Si ₃ Al as its constituent unit is preferred, and a solid particle containing SiO ₂ or Si ₃ Al as the main component of its structural unit. In this case, the term "major component" refers to a component contained in the inorganic silica-based filler in an amount of 50% (mass.) or more, preferably 70% (mass.) or more, and more preferably 80% (mass. .) and more.

[0145]

Examples of the silica-based inorganic filler include, but are not limited to, silica, clay, talc, mica, diatomite, wollastonite, montmorillonite, zeolite, and inorganic fibrous materials such as glass fiber.

In addition, examples include a silica-based inorganic filler having a hydrophobized surface, and a mixture of a silica-based inorganic filler and an inorganic silica-free filler. From the viewpoint of strength and abrasion resistance, among them, silica and glass fiber are preferable, and silica is more preferable. Examples of silica include dry process silica, wet process silica, and synthetic silicate silica. From the viewpoint of showing silica an excellent effect of improving the breaking performance and balance of wet skid resistance, among these silicas, wet process silica is preferable.

[0146]

From the point of view of obtaining good abrasion resistance and degradation characteristics of the rubber composition in practice, the specific surface area of the silica-based inorganic filler obtained by the BET adsorption method obtained by using the nitrogen adsorption method is preferably in the range of 100 m ² /g or more to 300 m ² /g or less, and more preferably from 170 m ² /g or more to 250 m ² /g or less. In addition, if necessary, a silica-based inorganic filler having a relatively small specific surface area (for example, having a specific surface area of 200 m ² /g or less) and a silica-based inorganic filler can be used in combination, characterized by a relatively large specific surface area (for example, characterized by a specific surface area of 200 m ² /g or more).

In particular, the use of a silica-based inorganic filler having a relatively large specific surface area (for example, having a specific surface area of 200 m ² /g or more) in the conjugated diene-based polymer of the present embodiment exhibits the effects of increasing the dispersibility of silica. , and especially improvement in abrasion resistance, and tends to have a well-balanced good fracture performance and low hysteresis loss performance.

[0147]

The level of the silica-based inorganic filler in the rubber composition of the present embodiment is preferably 5.0 mass parts or more to 150 mass parts or less, more preferably 20 mass parts or more to 100 mass parts or less, when calculating per 100 mass parts of the rubber component containing the conjugated diene-based polymer of the present embodiment. From the viewpoint of exhibiting the effect of adding the silica-based inorganic filler, the content of the silica-based inorganic filler is preferably 5.0 mass parts or more, and from the viewpoint of sufficiently dispersing the silica-based inorganic filler to achieve sufficient processability and mechanical strength of the rubber composition, this level is preferably 150 mass parts or less.

[0148]

Examples of carbon black include, but are not limited to, grades of carbon black SRF (semi-reinforcing furnace black), FEF (fast extruding furnace black), HAF (wear resistant furnace black), ISAF (high wear resistant furnace black), and SAF (super wear resistant furnace black). ). Among these, preferred is carbon black having a specific surface area determined by nitrogen adsorption of 50 m ² /g or more and an absorption value of dibutyl phthalate (DBT) oil of 80 ml/100 g or less.

[0149]

The content of carbon black is preferably 0.5 mass parts or more to 100 mass parts or less, more preferably 3.0 mass parts or more to 100 mass parts or less, and further preferably 5.0 mass parts or more to 50 mass parts or less, based on 100 mass parts of the rubber component containing the conjugated diene-based polymer of the present embodiment. From the point of view of exhibiting performance required when used as a tire and the like, such as tire dry grip performance and conductivity, the carbon black level is preferably 0.5 mass parts or more, and from the point of view of dispersibility, the level the content is preferably 100 mass parts or less.

[0150]

The term "metal oxide" refers to a solid particle containing the main component of its constituent structural unit, described by the chemical formula MxOy (where M is a metal atom, and each of x and y is independently an integer in the range from 1 to 6).

Examples of the metal oxide include, but are not limited to, alumina, titanium dioxide, magnesium oxide, and zinc oxide.

Examples of metal hydroxide include, but are not limited to, aluminum hydroxide, magnesium hydroxide, and zirconium hydroxide.

[0151]

The rubber composition may contain a silane coupling agent.

The silane coupling agent is preferably a compound that has the function of providing a closer interaction between the rubber component and the inorganic filler, contains a group characterized by an affinity or binding energy with respect to both the rubber component and, in particular, to the silica-based inorganic filler, and contains in one molecule a sulfur bond site and a site of an alkoxysilyl group or a silanol group. Examples of such a compound include bis[3-(triethoxysilyl)propyl]tetrasulfide, bis[3-(triethoxysilyl)propyl]disulfide and bis[2-(triethoxysilyl)ethyl]tetrasulfide.

[0152]

The content level of the silane coupling agent is preferably 0.1 mass parts or more to 30 mass parts or less, more preferably 0.5 mass parts or more to 20 mass parts or less, and further preferably 1.0 mass parts and more up to 15 mass parts and less, calculated on 100 mass parts of the filler. For the case where the content level of the silane coupling agent falls within the above range, there is a tendency to be able to obtain a more noticeable effect of adding the silane coupling agent.

[0153]

From the viewpoint of improving processability, the rubber composition of the present embodiment may contain a rubber softener.

As a rubber softener, mineral oil or a liquid or low molecular weight synthetic softener is suitably used.

Mineral oil based rubber softener, which is used for softening, foaming and improving the processability of rubber and referred to as "process oil" or "filling oil", is a mixture of an aromatic ring, a naphthenic ring and a paraffin chain, and a corresponding softener, in which the number of carbon atoms in the paraffin chain is 50% or more of the number of all carbon atoms, denoted by the term "paraffin-based softener", the corresponding softener, in which the number of carbon atoms in the naphthenic ring is in the range from 30% or more to 45% or less based on the number of all carbon atoms, is referred to as "naphthenic-based softener", and the corresponding softener, whose number of aromatic carbon atoms exceeds 30% of the number of total carbon atoms, is referred to as "aromatic-based softener".

When the conjugated diene-based polymer of the present embodiment is in the form of a copolymer of a conjugated diene compound and a vinyl aromatic compound, the rubber softener used is preferably an appropriate softener having an appropriate level of aromatic content, since such a softener tends to achieve good compatibility with the copolymer.

[0154]

The content of the rubber softener is preferably 0 mass parts or more to 100 mass parts or less, more preferably 10 mass parts or more to 90 mass parts or less, and further preferably 30 mass parts or more to 90 mass parts or less, based on 100 mass parts of the rubber component containing the conjugated diene-based polymer of the present embodiment. In the case of a rubber softener content level of 100 parts by mass or less, based on 100 parts by mass of the rubber component, there is a tendency to suppress sweating and suppress tackiness of the surface of the rubber composition of the present embodiment.

[0155]

Examples of the mixing method of materials constituting the rubber composition of the present embodiment, such as a rubber component containing a conjugated diene polymer of the present embodiment, a silica-based inorganic filler, carbon black or other filler, a silane coupling agent, and an additive such as a rubber softener, include, but are not limited to, a melt kneading method using a general purpose mixer such as an open roll, a Banbury mixer, a kneader, a single shaft screw extruder, a twin shaft screw extruder, or a multi shaft screw extruder, and a method in which the respective components are melted and mixed after removal of the solvent by heating.

From the point of view of productivity and high kneadability among these methods, the melt kneading method using rollers, a Banbury mixer, a kneader or an extruder is preferred. In addition, either a method in which the materials constituting the rubber composition of the present embodiment are kneaded together or a method in which the materials are mixed discontinuously at several points in time.

[0156]

The rubber composition of the present embodiment may be a vulcanized composition vulcanized using a vulcanizer. Examples of the vulcanizer include, but are not limited to, radical generators such as organic peroxides and azo compounds, oxime compounds, nitroso compounds, polyamine compounds, sulfur, and sulfur compounds.

Sulfur compounds include sulfur monochloride, sulfur dichloride, disulfide compounds and high molecular weight polysulfide compounds.

The content of the vulcanizing agent is preferably in the range of 0.01 mass parts or more to 20 mass parts or less, and more preferably 0.1 mass parts or more to 15 mass parts or less, based on 100 mass parts of the rubber component containing the conjugated diene polymer of the present embodiment. As the vulcanization method, any known method can be applied, and the vulcanization temperature is preferably 120°C or more to 200°C or less, and more preferably 140°C or more to 180°C or less.

[0157]

For vulcanization, if necessary, a vulcanization accelerator can be used.

As the vulcanization accelerator, any of the known materials can be used, and examples include but are not limited to: sulfenamide-based, guanidine-based, thiuram-based, aldehyde-amine-based, aldehyde-ammonia-based, thiazole-based, thiourea-based vulcanizing accelerators and a dithiocarbamate base.

In addition, examples of the vulcanization aid include, but are not limited to, zinc oxide and stearic acid.

The content of the vulcanization accelerator is preferably 0.01 mass parts or more to 20 mass parts or less, and more preferably 0.1 mass parts or more to 15 mass parts or less, based on 100 mass parts of the rubber component, containing a conjugated diene-based polymer of the present embodiment.

[0158]

As long as the purpose of the present embodiment is not impaired, the rubber composition of the present embodiment may contain various additives such as another emollient excluding the emollients described above, a filler, a heat stabilizer, an antistatic agent, a weather stabilizer, an antioxidant, a dye, and a lubricant.

As another softener, any of the known softeners can be used.

Specific examples of another filler include calcium carbonate, magnesium carbonate, aluminum sulfate and barium sulfate.

As each member selected from a heat stabilizer, an antistatic agent, a weather stabilizer, an antioxidant, a dye, and a lubricant, any of the known materials can be used.

[0159]

[Tire]

The rubber composition of the present embodiment is suitably used as a rubber composition for a tire.

In other words, the tire of the present embodiment contains the rubber composition of the present embodiment and is produced by processing the rubber composition of the present embodiment.

[0160]

The rubber composition of the present embodiment is applicable to, but not limited to, the following: various tires such as a fuel-efficient tire, an all-weather tire, a high-performance tire, and a non-studded tire; and various areas of the tire such as the tread, carcass, sidewall and bead. In particular, when using the rubber composition of the present embodiment as a rubber composition for a tire, since the composition is excellent in balance between low hysteresis loss performance and wet skid resistance obtained when the material is in the form of a vulcanizate, and abrasion resistance, more suitable for use, it is used as a tread of a fuel-efficient tire or a high-tech tire.

Examples

[0161]

Now, the present embodiment will be described in more detail with reference to specific examples and comparative examples, and as it should be noted, the present embodiment is not limited to the following examples and comparative examples at all.

Various physical properties from the Examples and Comparative Examples were measured using the following methods.

In the following Examples and Comparative Examples, the conjugated diene polymer obtained after the modification is referred to as "modified conjugated diene polymer". The corresponding polymer obtained before the modification is referred to as "non-modified conjugated diene polymer".

[0162]

(Physical property 1) Amount of bound styrene

One hundred (100) mg of the modified conjugated diene based polymer used as a sample was dissolved in chloroform by diluting to 100 ml, and the resulting product was used as a measurement sample. Based on the absorption value of the phenyl group of styrene in the UV wavelength region (approximately 254 nm), the amount of bound styrene (% (wt.)) was measured based on 100% (wt.) of the sample of the modified polymer based on the conjugated diene (spectrophotometer "UV -2450, manufactured by Shimadzu Corporation).

[0163]

(Physical property 2) Microstructure of the butadiene section (number of 1,2-vinyl bond)

Fifty (50) mg of the modified conjugated diene polymer used as a sample was dissolved in 10 ml of carbon disulfide, and the resulting product was used as a measurement sample.

A solution cuvette was used to measure the infrared spectrum in the range from 600 to 1000 cm ^{- 1} and, in accordance with the calculation formula of the Hampton method (RR Hampton, Analytical Chemistry, 21, 923 (1949)) based on the optical density in the region of the prescribed wavelength, the microstructure of butadiene area, namely, the amount of 1,2-vinyl bond (% (mol)) (infrared Fourier transform spectrophotometer "FT-IR230", manufactured by JASCO Corporation).

[0164]

(Physical property 3) Molecular weight

Measurement conditions 1: The unmodified conjugated diene based polymer or modified conjugated diene based polymer used as a sample was measured to obtain a chromatogram using a GPC measuring apparatus (trade name "HLC-8320GPC" manufactured by Tosoh Corporation), including a sequence of three columns using a polystyrene-based gel as a filler, using a refractive index detector (trade name "HLC8020", manufactured by Tosoh Corporation), and based on the calibration curve obtained using a polystyrene standard, a mass average was obtained molecular weight (Mw), number average molecular weight (Mn), and molecular weight distribution (Mw/Mn).

THF (tetrahydrofuran) was used as an eluent containing 5 mmol/l of triethylamine. As columns, a column of the trade name "TSKguardcolumn Super MP(HZ)-H" manufactured by Tosoh Corporation was used, connected as a guard column in the previous stage with a sequence of three columns of the trade name "TSKgel Super Multipore HZ-H" manufactured by Tosoh Corporation.

Ten (10) mg of the measurement sample was dissolved in 10 ml of THF to obtain a measurement solution, and 10 µl of the measurement solution was injected into the GPC measurement apparatus to carry out measurement under the condition of an oven temperature of 40°C and a THF flow rate of 0, 35 ml/min.

Among the various samples subjected to measurement under the measurement conditions 1 described above, a sample having a molecular weight distribution (Mw/Mn) of less than 1.6 was once again subjected to measurement under the measurement conditions 2 described below. For samples measured under measurement conditions 1 and found to have a molecular weight distribution of 1.6 or more, the results obtained from measurement under measurement conditions 1 are shown in Tables 1 to 4.

[0165]

Measurement Conditions 2: The unmodified conjugated diene based polymer or the modified conjugated diene based polymer used as a sample was measured to obtain a chromatogram using a GPC measuring apparatus including a sequence of three columns using a polystyrene-based gel as a filler, and based on the calibration curve obtained using a polystyrene standard, the weight average molecular weight (Mw) and the number average molecular weight (Mn) were obtained.

THF was used as an eluent containing 5 mmol/L of triethylamine. As columns, a guard column of the trade name "TSKguardcolumn Super H-H" manufactured by Tosoh Corporation and columns of the trade names "TSKgel SuperH5000", "TSKgel SuperH6000" and "TSKgel SuperH7000" manufactured by Tosoh Corporation were used.

A refractive index detector (trade name "HLC8020", manufactured by Tosoh Corporation) was used under the condition of an oven temperature of 40°C and a THF flow rate of 0.6 ml/min. Ten (10) mg of the measurement sample was dissolved in 20 ml of THF to obtain a measurement solution, and 20 µl of the measurement solution was injected into the GPC measurement apparatus for measurement.

With respect to the sample subjected to measurement under measurement conditions 1 and found to have a molecular weight distribution of less than 1.6, the results obtained from measurement under measurement conditions 2 are shown in Tables 1 to 4.

[0166]

(Physical property 4) Shrinkage ratio (g’)

A modified conjugated diene based polymer was used as a sample, and a GPC measurement apparatus (trade name "GPCmax VE-2001", manufactured by Malvern Panalytical Ltd.) was used, including a sequence of three columns using a polystyrene-based gel as a filler. . The measurement was carried out using three detectors, i.e., a light scattering detector, a refractive index detector, and a viscosity detector, (trade name "TDA305", manufactured by Malvern Panalytical Ltd.) connected in this order in such a way that, based on the polystyrene standard, an absolute molecular a mass based on results obtained using a light scattering detector and a refractive index detector; and an intrinsic viscosity based on results obtained using a refractive index detector and a viscosity detector.

When using the constants (K and α) used in the expression describing the relationship between intrinsic viscosity and molecular weight [ƞ]=KMα ([ƞ]: intrinsic viscosity, M: molecular weight) with logK=-3.883 and α=0.771, a molecular weight M in the range of 1,000 to 2,000,000 was introduced to clarify the relationship _between the standard intrinsic viscosity [ƞ] ₀ and the molecular weight M. Using the thus obtained standard intrinsic viscosity [ƞ] 0, [ƞ]/[ƞ] ₀ was calculated from the ratio to each molecular weight M as a ratio to the standard intrinsic viscosity [ƞ] ₀ for the intrinsic viscosity [ƞ] at each molecular weight M of the sample obtained as a result of measurement in the three-dimensional GPC method, and the average value for the values thus obtained was determined as the shrinkage coefficient (g').

More specifically, this can be measured using the following method.

THF was used as an eluent containing 5 mmol/L of triethylamine.

As columns, a sequence of columns of trade names "TSKgel G4000HXL", "TSKgel G5000HXL" and "TSKgel G6000HXL" manufactured by Tosoh Corporation was used.

Twenty (20) mg of the measurement sample was dissolved in 10 ml of THF to obtain a measurement solution, and 100 μl of the measurement solution was injected into the GPC measurement apparatus for measurement under the condition of an oven temperature of 40°C and a THF flow rate of 1 ml /min

[0167]

(Physical Property 5) Mooney Viscosity of Polymer

An unmodified conjugated diene based polymer or a modified conjugated diene based polymer was used as a sample for measuring Mooney viscosity using a Mooney viscometer (trade name "VR1132" manufactured by Ueshima Seisakusho Co., Ltd.) according to JIS K6300 under using a rotor type L.

The measurement temperature was 110° C. when using the unmodified conjugated diene polymer as the sample, and 100° C. when using the modified conjugated diene polymer as the sample.

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

[0168]

(Physical property 6) Glass transition temperature (Tg)

A modified polymer based on a conjugated diene was used as a sample, a DSC3200S differential scanning calorimeter manufactured by Mac Science was used to record a curve in the DSC method in a helium flow at 50 ml/min and with an increase in temperature from -100°C to 20° C/min in accordance with the document ISO 22768:2006 and as the glass transition temperature was determined peak top (inflection point) of the differential curve in the DSC method thus obtained.

[0169]

(Physical property 7) Degree of modification

A modified conjugated diene-based polymer was used as a sample, and the measurement was carried out using the characteristic of adsorbing the modified base polymer component on a GPC column using a silica-based gel as a filler.

The degree of modification was obtained by measuring the amount of adsorption on a silica-based column based on the difference between the chromatogram measured using a polystyrene-based column and the chromatogram measured using a silica-based column obtained from a sample solution containing a sample and a low molecular weight polystyrene internal standard.

Specifically, the measurement was carried out in accordance with the following description of the invention.

For a sample found to have a molecular weight distribution of 1.6 or more as measured under measurement conditions 1 (physical property 3), measurements were made under the following measurement conditions 3. For a sample characterized as this molecular weight distribution was found to be less than 1.6 as measured under measurement conditions 1 (physical property 3), measurements were taken under the following measurement conditions 4. The results are shown in Tables 1 to 4.

[0170]

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

Measurement conditions 3: measurement conditions in the GPC method when using a polystyrene-based column:

An apparatus of the trade name "HLC-8320GPC" manufactured by Tosoh Corporation was used, THF was used as an eluent containing 5 mmol/L of triethylamine, and 10 μl of the sample solution was injected into the apparatus in order to obtain a chromatogram using a refractive index detector under the condition of an oven temperature column at 40° C. and a THF flow rate of 0.35 ml/min.

As columns, a sequence of three columns of the trade name "TSKgel Super Multipore HZ-H" and a guard column of the trade name "TSKguardcolumn SuperMP(HZ)-H" manufactured by Tosoh Corporation connected in the previous step were used.

[0171]

Measurement conditions 4: measurement conditions in the GPC method using a polystyrene-based column:

An apparatus of trade name "HLC-8320GPC" manufactured by Tosoh Corporation was used, THF was used as an eluent containing 5 mmol/L of triethylamine, and 20 μl of sample solution was injected into the apparatus for measurement purposes.

As columns, a guard column of the trade name "TSKguardcolumn Super H-H" manufactured by Tosoh Corporation and columns of the trade names "TSKgel SuperH5000", "TSKgel SuperH6000" and "TSKgel SuperH7000" manufactured by Tosoh Corporation were used. A chromatogram was obtained by performing a measurement using a refractive index detector (HLC8020, manufactured by Tosoh Corporation) under a column oven temperature of 40° C. and a THF flow rate of 0.6 ml/min.

[0172]

Measurement conditions in the GPC method using a column based on silica:

The apparatus of the trade name "HLC-8320GPC" manufactured by Tosoh Corporation was used, THF was used as the eluent, and 50 μl of sample solution was injected into the apparatus to obtain a chromatogram using a refractive index detector under the conditions of a column oven temperature of 40°C and a flow rate of THF 0 .5 ml/min. A sequence of columns of the trade names "Zorbax PSM-1000S", "PSM-300S" and "PSM-60S" and a guard column of the trade name "DIOL 4.6 × 12.5 mm 5 micron" connected at the previous stage were used.

[0173]

Method for calculating the degree of modification:

Based on the assumption that the total peak area in the chromatogram obtained using a polystyrene-based column is equal to 100, the peak area of the sample P1 corresponds, the peak area of the polystyrene standard P2 is equal, the total peak area of the chromatogram obtained using a silica-based column is equal, 100, according to the peak area of the sample P3 and according to the peak area of the polystyrene standard P4, the degree of modification (%) was obtained according to the following expression:

Degree of modification (%)=[1 - (P2 × P3)/(P1 × P4)] × 100,

where P1+P2=P3+P4=100.

[0174]

(Physical property 8) Number of branches (Bn)

A modified conjugated diene based polymer was used as a sample, and a GPC measurement apparatus (trade name "GPCmax VE-2001", manufactured by Malvern Panalytical Ltd.) was used, including a sequence of three columns using a polystyrene-based gel as a filler. . The measurement was carried out using three detectors, i.e., a light scattering detector, a refractive index detector and a viscosity detector, (trade name "TDA305", manufactured by Malvern Panalytical Ltd.) connected in this order, and based on the polystyrene standard, the absolute molecular weight of based on results obtained using a light scattering detector and a refractive index detector, and intrinsic viscosity based on results obtained using a refractive index detector and a viscosity detector.

When using the constants (K and α) used in the expression describing the relationship between intrinsic viscosity and molecular weight [ƞ]=KMα ([ƞ]: intrinsic viscosity, M: molecular weight) with logK=-3.883 and α=0.771, a molecular weight M in the range of 1,000 to 2,000,000 was introduced to clarify the relationship _between the standard intrinsic viscosity [ƞ] ₀ and the molecular weight M. Using the thus obtained standard intrinsic viscosity [ƞ] 0, [ƞ]/[ƞ] ₀ was calculated from the ratio to each molecular weight M as a ratio to the standard intrinsic viscosity [ƞ] ₀ for the intrinsic viscosity [ƞ] at each molecular weight M of the sample obtained as a result of measurement in the three-dimensional GPC method, and the average value for the values thus obtained was determined as the shrinkage coefficient (g').

Thereafter, the shrinkage factor (g') thus obtained was used to calculate the number of branches (Bn) determined by using the expression g'=6Bn/{(Bn+1)(Bn+2)}.

THF was used as an eluent containing 5 mmol/L of triethylamine.

As columns, a sequence of columns of trade names "TSKgel G4000HXL", "TSKgel G5000HXL" and "TSKgel G6000HXL" manufactured by Tosoh Corporation was used.

Twenty (20) mg of the measurement sample was dissolved in 10 ml of THF to obtain a measurement solution, and 100 μl of the measurement solution was injected into the GPC measurement apparatus for measurement under the condition of an oven temperature of 40°C and a THF flow rate of 1 ml /min

[0175]

(Physical property 9) Change (ΔT) of the oxidation start temperature due to the application of heat load

The thermal stability was evaluated by measuring the change in the temperature of the onset of oxidation due to the application of a thermal load.

Loading 50 g of the modified conjugated diene-based polymer into a Labo Plastomill 30C150 (Toyo Seiki Seisaku-sho, Ltd.) and setting the bulk temperature to 50°C, three kneading cycles were performed, each kneading at 120 vol./ min for 5 minutes, and then stopped for 5 minutes.

The oxidation start temperature for the modified conjugated diene polymer was measured before and after kneading using a thermogravimetric/differential thermal analyzer (STA 7200 RV, HITACHI).

In an air atmosphere, the temperature was increased from 30° C. to 500° C. under the condition of 10° C./min, and the temperature at which an endothermic peak was detected was determined as the oxidation start temperature. The oxidation start temperature difference for the modified conjugated diene polymer due to the application of heat load was obtained as ΔT, which was used as an index of heat resistance.

[0176]

(Example 1) Modified conjugated diene based polymer (Example 1)

Two pressure vessels, each a stirred tank reactor, having an internal volume of 10 liters and a ratio (L/D) between internal height (L) and diameter (D) of 4.0, having an inlet at the bottom parts and an outlet at the top and provided with a stirrer and a temperature control jacket were connected to each other as polymerization reactors.

1,3-butadiene, styrene and n-hexane, from which the water content had previously been removed, were mixed under the conditions of 13.0 g/min, 10.0 g/min and 175.2 g/min, respectively. In a static mixer located in the middle of the pipe for supplying the thus obtained mixed solution to the inlet of the reactor, n-butyllithium used to deactivate residual impurities was added and mixed in an amount of 0.103 mmol/min, and the resulting product was continuously fed to the bottom of the reactor . In addition, 2,2-bis(2-oxolanyl)propane used as a polar material and n-butyllithium used as a polymerization initiator were fed at a flow rate of 0.081 mmol/min and 0.143 mmol/min, respectively, to the lower part of the first reactor, in which the materials were intensively mixed using a stirrer, and, in addition, a dissected portion of 1,3-butadiene was added from the upper section of the first reactor under conditions of 5.6 g/min, and the internal temperature of the reactor was maintained at 67 °C.

The polymer solution thus obtained was continuously withdrawn from the top of the first reactor to be continuously fed to the bottom of the second reactor in order to continue the reaction at 70° C., and the resulting product was further fed to the static mixer from the top of the second reactor. With sufficient stabilization of the polymerization from the bottom of the second reactor at a flow rate of 0.0190 mmol/min was added trimethoxy(4-vinylphenyl)silane (demonstrated as "BS-1" in the table), used as a branching agent. When stabilizing the polymerization reaction and the branching reaction, a small amount of the polymer solution based on the conjugated diene was taken before the addition of the modifier, and an antioxidant (BHT) was added here in the amount of 0.2 g per 100 g of the polymer, after which the solution was removed and the Mooney viscosity was measured at 110°C and various molecular weights. Table 1 also shows other physical properties.

[0177]

Thereafter, 2,2-dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza-2-silacyclopentane (demonstrated as " A" in the table) and the resulting product was mixed using a static mixer to carry out the modification reaction. In this case, the time until the addition of the modifier to the polymer solution flowing from the outlet of the reactor was 4.8 minutes, the temperature was 68°C, and the difference between the temperature in the polymerization stage and the temperature up to the addition of the modifier was 2°C. To the polymer solution subjected to the modification reaction, an antioxidant (BHT) was added continuously at 0.055 g/min (n-hexane solution) in an amount of 0.2 g per 100 g of polymer to complete the modification reaction. An oil (JOMO Process NC 140, manufactured by JX Nippon Oil & Energy Corporation) was continuously added at the same time as the antioxidant in an amount of 37.5 g per 100 g of polymer, and the resulting product was mixed using a static mixer. The solvent was removed by stripping, and thus a modified conjugated diene polymer was obtained (sample 1). The physical properties of Sample 1 are shown in Table 1.

[0178]

(Example 2) Modified conjugated diene based polymer (sample 2)

A modified conjugated diene based polymer (sample 2) was prepared in the same manner as in example 1 except for changing the modifier from 2,2-dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza-2-silacyclopentane to tris(3-trimethoxysilylpropyl)amine (demonstrated as "B" in the table) and changing its addition amount to 0.0250 mmol/min. The physical properties of Sample 2 are shown in Table 1.

[0179]

(Example 3) Modified Conjugated Diene Polymer (Sample 3)

A modified conjugated diene based polymer (sample 3) was prepared in the same manner as in example 1, except for changing the modifier from 2,2-dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza-2-silacyclopentane to tetrakis(3-trimethoxysilylpropyl)-1,3-propanediamine (demonstrated as "C" in the table) and changing its addition amount to 0.0190 mmol/min. The physical properties of Sample 3 are shown in Table 1.

[0180]

(Example 4) Modified Conjugated Diene Polymer (Sample 4)

A modified conjugated diene based polymer (sample 4) was obtained in the same manner as in example 1, except for changing the modifier from 2,2-dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza-2-silacyclopentane to tetrakis(3-trimethoxysilylpropyl)-1,3-propanediamine (demonstrated as "C" in the table) and changing its addition amount to 0.0160 mmol/min. The physical properties of Sample 4 are shown in Table 1.

[0181]

(Example 5) Modified Conjugated Diene Polymer (Sample 5)

A modified conjugated diene based polymer (sample 5) was prepared in the same manner as in Example 1 except for changing the branching agent from trimethoxy(4-vinylphenyl)silane to dimethylmethoxy(4-vinylphenyl)silane (demonstrated as "BS -2" in the table) and changing its added amount with the transition to 0.0350 mmol/min. The physical properties of Sample 5 are shown in Table 1.

[0182]

(Example 6) Modified Conjugated Diene Polymer (Sample 6)

A modified conjugated diene based polymer (sample 6) was prepared in the same manner as in Example 1 except for changing the branching agent from trimethoxy(4-vinylphenyl)silane to dimethylmethoxy(4-vinylphenyl)silane (demonstrated as "BS -2" in the table), changes in its added amount with the transition to 0.0350 mmol / min, changes in the modifier with the transition from 2,2-dimethoxy-1- (3-trimethoxysilylpropyl) -1-aza-2-silacyclopentane to tris ( 3-trimethoxysilylpropyl)amine (demonstrated as "B" in the table) and changes in its addition amount to 0.0250 mmol/min. The physical properties of Sample 6 are shown in Table 1.

[0183]

(Example 7) Modified Conjugated Diene Polymer (Sample 7)

A modified conjugated diene based polymer (Sample 7) was prepared in the same manner as in Example 1 except for changing the branching agent from trimethoxy(4-vinylphenyl)silane to dimethylmethoxy(4-vinylphenyl)silane (demonstrated as "BS -2" in the table), changes in its added amount with the transition to 0.0350 mmol / min, changes in the modifier with the transition from 2,2-dimethoxy-1- (3-trimethoxysilylpropyl) -1-aza-2-silacyclopentane to tetrakis ( 3-trimethoxysilylpropyl)-1,3-propanediamine (demonstrated as "C" in the table) and changing its addition amount to 0.0160 mmol/min. The physical properties of Sample 7 are shown in Table 1.

[0184]

(Example 8) Modified Conjugated Diene Polymer (Sample 8)

A modified conjugated diene based polymer (Sample 8) was prepared in the same manner as in Example 1 except for changing the branching agent from trimethoxy(4-vinylphenyl)silane to 1,1-bis(4-dimethylmethoxysilylphenyl)ethylene ( shown as "BS-3" in the table) and changing its added amount to 0.0120 mmol/min. The physical properties of Sample 8 are shown in Table 1.

[0185]

(Example 9) Modified Conjugated Diene Polymer (Sample 9)

A modified conjugated diene based polymer (Sample 9) was prepared in the same manner as in Example 1 except for changing the branching agent from trimethoxy(4-vinylphenyl)silane to 1,1-bis(4-dimethylmethoxysilylphenyl)ethylene ( shown as "BS-3" in the table), changes in its addition amount going to 0.0120 mmol/min, modifier changes going from 2,2-dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza-2- silacyclopentane to tris(3-trimethoxysilylpropyl)amine (demonstrated as "B" in the table) and changing its addition amount to 0.0250 mmol/min. The physical properties of Sample 9 are shown in Table 1.

[0186]

(Example 10) Modified Conjugated Diene Polymer (Sample 10)

A modified conjugated diene based polymer (sample 10) was prepared in the same manner as in Example 1 except for changing the branching agent from trimethoxy(4-vinylphenyl)silane to 1,1-bis(4-dimethylmethoxysilylphenyl)ethylene ( shown as "BS-3" in the table), changes in its addition amount going to 0.0120 mmol/min, modifier changes going from 2,2-dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza-2- silacyclopentane to tetrakis(3-trimethoxysilylpropyl)-1,3-propanediamine (demonstrated as "C" in the table) and changing its addition amount to 0.0160 mmol/min. The physical properties of Sample 10 are shown in Table 1.

[0187]

(Example 11) Modified Conjugated Diene Polymer (Sample 11)

A modified conjugated diene based polymer (Sample 11) was prepared in the same manner as in Example 1 except for changing the branching agent from trimethoxy(4-vinylphenyl)silane to 1,1-bis(4-trimethoxysilylphenyl)ethylene ( shown as "BS-4" in the table) and changing its added amount to 0.0210 mmol/min. The physical properties of Sample 11 are shown in Table 2.

[0188]

(Example 12) Modified Conjugated Diene Polymer (Sample 12)

A modified conjugated diene based polymer (Sample 12) was prepared in the same manner as in Example 1 except for changing the branching agent from trimethoxy(4-vinylphenyl)silane to 1,1-bis(4-trimethoxysilylphenyl)ethylene ( shown as "BS-4" in the table), changes in its addition amount going to 0.0210 mmol/min, modifier changes going from 2,2-dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza-2- silacyclopentane to tris(3-trimethoxysilylpropyl)amine (demonstrated as "B" in the table) and changing its addition amount to 0.0250 mmol/min. The physical properties of Sample 12 are shown in Table 2.

[0189]

(Example 13) Modified Conjugated Diene Polymer (Sample 13)

A modified conjugated diene based polymer (sample 13) was prepared in the same manner as in Example 1 except for changing the branching agent from trimethoxy(4-vinylphenyl)silane to 1,1-bis(4-trimethoxysilylphenyl)ethylene ( shown as "BS-4" in the table), changes in its addition amount going to 0.0210 mmol/min, modifier changes going from 2,2-dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza-2- silacyclopentane to tetrakis(3-trimethoxysilylpropyl)-1,3-propanediamine (demonstrated as "C" in the table) and changing its addition amount to 0.0160 mmol/min. The physical properties of Sample 13 are shown in Table 2.

[0190]

(Example 14) Modified Conjugated Diene Polymer (Sample 14)

A modified conjugated diene based polymer (sample 14) was prepared in the same manner as in Example 1 except for changing the branching agent from trimethoxy(4-vinylphenyl)silane to trichloro(4-vinylphenyl)silane (demonstrated as "BS -5" in the table). The physical properties of Sample 14 are shown in Table 2.

[0191]

(Example 15) Modified Conjugated Diene Polymer (Sample 15)

A modified conjugated diene based polymer (sample 15) was prepared in the same manner as in Example 1, except for changing the branching agent from trimethoxy(4-vinylphenyl)silane to trichloro(4-vinylphenyl)silane (demonstrated as "BS -5" in the table), modifier changes from 2,2-dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza-2-silacyclopentane to tris(3-trimethoxysilylpropyl)amine (demonstrated as "B" in the table) and changing its added amount with the transition to 0.0250 mmol/min. The physical properties of Sample 15 are shown in Table 2.

[0192]

(Example 16) Modified Conjugated Diene Polymer (Sample 16)

A modified conjugated diene based polymer (Sample 16) was prepared in the same manner as in Example 1 except for changing the branching agent from trimethoxy(4-vinylphenyl)silane to trichloro(4-vinylphenyl)silane (demonstrated as "BS -5" in the table), modifier change from 2,2-dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza-2-silacyclopentane to tetrakis(3-trimethoxysilylpropyl)-1,3-propanediamine (demonstrated as " C" in the table) and changing its added amount with the transition to 0.0160 mmol / min. The physical properties of Sample 16 are shown in Table 2.

[0193]

(Example 17) Modified Conjugated Diene Polymer (Sample 17)

The modified conjugated diene based polymer (sample 17) was prepared in the same manner as in Example 1, except for changing the butadiene feed amount to 12.0 g/min and changing the butadiene cut feed amount to 6.6 g/min The physical properties of Sample 17 are shown in Table 2.

[0194]

(Example 18) Modified Conjugated Diene Polymer (Sample 18)

A modified conjugated diene based polymer (sample 18) was prepared in the same manner as in Example 1, except for changing the butadiene feed amount to 10.0 g/min and changing the butadiene cut feed amount to 8.6 g/min The physical properties of Sample 18 are shown in Table 2.

[0195]

(Example 19) Modified Conjugated Diene Polymer (Sample 19)

The modified conjugated diene based polymer (sample 19) was prepared in the same manner as in Example 1, except for changing the butadiene feed amount to 8.0 g/min and changing the butadiene cut feed amount to 10.6 g/min The physical properties of Sample 19 are shown in Table 2.

[0196]

(Example 20) Modified Conjugated Diene Polymer (Sample 20)

A modified conjugated diene based polymer (sample 20) was prepared in the same manner as in Example 1, except for changing the butadiene feed amount to 15.0 g/min and changing the butadiene cut feed amount to 3.6 g/min The physical properties of Sample 20 are shown in Table 2.

[0197]

(Example 21) Modified Conjugated Diene Polymer (Sample 21)

A modified conjugated diene based polymer (Sample 21) was prepared in the same manner as in Example 1 except for changing the modifier from 2,2-dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza-2-silacyclopentane to tetraethoxysilane (demonstrated as "D" in the table) and changing its addition amount to 0.0160 mmol/min. The physical properties of Sample 21 are shown in Table 2.

[0198]

(Comparative Example 1) Modified Conjugated Diene Resin (Sample 22)

A modified conjugated diene based polymer (sample 22) was prepared in the same manner as in Example 1, except for changing the butadiene feed amount to 15.0 g/min and changing the butadiene cut feed amount to 3.6 g/min The physical properties of Sample 22 are shown in Table 3.

[0199]

(Comparative Example 2) Modified Conjugated Diene Resin (Sample 23)

The modified conjugated diene based polymer (sample 23) was prepared in the same manner as in Example 1, except for changing the butadiene feed amount to 17.2 g/min and changing the butadiene cut feed amount to 1.4 g/min The physical properties of Sample 23 are shown in Table 3.

[0200]

(Comparative Example 3) Modified Conjugated Diene Resin (Sample 24)

A modified conjugated diene based polymer (sample 24) was prepared in the same manner as in Example 1, except for changing the butadiene feed amount to 18.6 g/min and changing the butadiene cut feed amount to 0 g/min. min. The physical properties of Sample 24 are shown in Table 3.

[0201]

(Comparative Example 4) Modified Conjugated Diene Resin (Sample 25)

A modified conjugated diene based polymer (sample 25) was prepared in the same manner as in Example 1 except for not adding a branching agent. The physical properties of Sample 25 are shown in Table 3.

[0202]

(Comparative Example 5) Modified Conjugated Diene Resin (Sample 26)

A modified conjugated diene based polymer (Sample 26) was prepared in the same manner as in Example 1 except for changing the modifier from 2,2-dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza-2-silacyclopentane to tris(3-trimethoxysilylpropyl)amine (demonstrated as "B" in the table) and changing its addition amount to 0.0250 mmol/min. The physical properties of Sample 26 are shown in Table 3.

[0203]

(Comparative Example 6) Modified Conjugated Diene Resin (Sample 27)

A modified conjugated diene based polymer (Sample 27) was prepared in the same manner as in Example 1 except for changing the modifier from 2,2-dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza-2-silacyclopentane to tetrakis(3-trimethoxysilylpropyl)-1,3-propanediamine (demonstrated as "C" in the table) and changing its addition amount to 0.0160 mmol/min. The physical properties of Sample 27 are shown in Table 3.

[0204]

(Example 22) Modified Conjugated Diene Polymer (Sample 28)

A modified conjugated diene based polymer (sample 28) was prepared in the same manner as in Example 3, except for changing the butadiene feed amount to 17.6 g/min, changing the butadiene cut feed amount to 7.5 g/min and change the amount of styrene supplied with the transition to 3.5 g/min. The physical properties of Sample 28 are shown in Table 4.

[0205]

(Example 23) Modified Conjugated Diene Polymer (Sample 29)

A modified conjugated diene based polymer (sample 29) was prepared in the same manner as in Example 3, except for changing the butadiene feed amount to 19.7 g/min, changing the butadiene cut feed amount to 8.4 g/min and change the amount of styrene supplied with the transition to 0.5 g/min. The physical properties of Sample 29 are shown in Table 4.

[0206]

(Example 24) Modified Conjugated Diene Polymer (Sample 30)

A modified conjugated diene based polymer (sample 30) was prepared in the same manner as in Example 3, except for changing the feed amount of n-butyllithium as polymerization initiator to 0.188 mmol/min and changing the feed amount of modifier to 0 .0230 mmol/min. The physical properties of Sample 30 are shown in Table 4.

[0207]

(Example 25) Modified Conjugated Diene Polymer (Sample 31)

The modified conjugated diene polymer (sample 31) was obtained in the same manner as in example 1, except for changing the amount of butadiene fed to 17.6 g/min, changing the amount of dissected butadiene fed to 7.5 g/min and change the amount of styrene supplied with the transition to 3.5 g/min. The physical properties of Sample 31 are shown in Table 4.

[0208]

(Example 26) Modified Conjugated Diene Polymer (Sample 32)

A modified conjugated diene based polymer (sample 32) was prepared in the same manner as in Example 3, except for changing the butadiene feed amount to 21.5 g/min, changing the butadiene cut feed amount to 3.6 g/min and change the amount of styrene supplied with the transition to 3.5 g/min. The physical properties of Sample 32 are shown in Table 4.

[0209]

(Example 27) Modified Conjugated Diene Polymer (Sample 33)

A modified conjugated diene based polymer (sample 33) was prepared in the same manner as in Example 3, except for changing the butadiene feed amount to 11.6 g/min, changing the butadiene cut feed amount to 5.0 g/min and changes in the amount of styrene supplied with the transition to 12.0 g/min. The physical properties of Sample 33 are shown in Table 4.

[0210]

(Comparative Example 7) Modified Conjugated Diene Resin (Sample 34)

The modified conjugated diene based polymer (Sample 34) was prepared in the same manner as in Example 3, except for not feeding styrene, changing the butadiene feeding amount to 20.0 g/min, and changing the feeding amount of the dissected butadiene batch to 8.6 g/min. The physical properties of Sample 34 are shown in Table 4.

[0211]

(Comparative Example 8) Modified Conjugated Diene Resin (Sample 35)

A modified conjugated diene based polymer (Sample 35) was prepared in the same manner as in Example 3, except for not feeding the branching agent, not feeding the dissected portion of butadiene, changing the butadiene feed amount to 18.6 g/min, and changing the feed amount styrene with the transition to 10.0 g / min. The physical properties of Sample 35 are shown in Table 4.

[0212]

(Comparative Example 9) Modified Conjugated Diene Resin (Sample 36)

The modified conjugated diene based polymer (Sample 36) was prepared in the same manner as in Example 3, except for changing the butadiene feed amount to 24.7 g/min, changing the butadiene cut feed amount to 4.4 g/min and change the amount of styrene supplied with the transition to 0.5 g/min. The physical properties of Sample 36 are shown in Table 4.

[0213]

[Table 1]

Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 Example 9 Example 10 Modified polymer based on conjugated diene (sample no.) 1 2 3 4 5 6 7 8 9 10 Polymerization conditions 1,3-butadiene (g/min) 13.0 13.0 13.0 13.0 13.0 13.0 13.0 13.0 13.0 13.0 Dissected portion of 1,3-butadiene (g/min) 5.6 5.6 5.6 5.6 5.6 5.6 5.6 5.6 5.6 5.6 Styrene (g/min) 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 n-hexane (g/min) 175.2 175.2 175.2 175.2 175.2 175.2 175.2 175.2 175.2 175.2 Polymerization temperature (°C) 70 70 70 70 70 70 70 70 70 70 n-butyllithium for decontamination of residual impurities (mmol/min) 0.103 0.103 0.103 0.103 0.103 0.103 0.103 0.103 0.103 0.103 n-butyllithium polymerization initiator (mmol/min) 0.143 0.143 0.143 0.143 0.143 0.143 0.143 0.143 0.143 0.143 Amount of added polar material (mmol/min) 0.081 0.081 0.081 0.081 0.081 0.081 0.081 0.081 0.081 0.081 Branching agent Type BS-1 BS-1 BS-1 BS-1 BS-2 BS-2 BS-2 BS-3 BS-3 BS-3 Added quantity (mmol/min) 0.0190 0.0190 0.0190 0.0190 0.0350 0.0350 0.0350 0.0120 0.0120 0.0120 Modifier Type A B C C A B C A B C Added quantity (mmol/min) 0.0360 0.0250 0.0190 0.0160 0.0360 0.0250 0.0160 0.0360 0.0250 0.0160 Physical Properties Conjugated diene based polymer (Physical property 3) Weight average molecular weight (10 ⁴ g/mol) 63.9 63.9 63.9 63.9 60.3 60.3 60.3 74.5 74.5 74.5 (Physical property 3) Number average molecular weight (10 ⁴ g/mol) 33.1 33.1 33.1 33.1 32.2 32.2 32.2 37.8 37.8 37.8 (Physical Property 5) Mooney Viscosity of Resin (110°C) 92.1 92.1 92.1 92.1 88.2 88.2 88.2 99.1 99.1 99.1 (Physical property 3) Mw/Mn 1.93 1.93 1.93 1.93 1.87 1.87 1.87 1.97 1.97 1.97 Modified polymer based on conjugated diene (Physical property 1) Amount of bound styrene (% (mass.)) 35 35 35 35 35 35 35 35 35 35 (Physical property 2) Amount of bonded vinyl (amount of 1,2-vinyl bond) (% (mol.)) 40 40 40 40 40 40 40 40 40 40 (Physical property 3) Weight average molecular weight (10 ⁴ g/mol) 92.0 96.0 105.3 106.0 86.8 90.6 99.4 115.0 121.0 135.0 (Physical property 3) Number average molecular weight (10 ⁴ g/mol) 46.7 48.7 53.4 54.6 43.8 46.5 51.5 57.2 62.4 69.6 (Physical property 3) Mw/Mn 1.97 1.97 1.97 1.94 1.98 1.95 1.93 2.01 1.94 1.94 (Physical property 4) Shrinkage ratio (g’) 0.52 0.40 0.32 0.26 0.53 0.45 0.37 0.28 0.21 0.18 (Physical Property 5) Mooney Viscosity of Resin (100°C) 83 83 83 82 79 84 82 81 84 82 (Physical property 6) Glass transition temperature (°C) - 23 - 23 - 23 - 23 - 23 - 23 - 23 - 23 - 23 - 23 (Physical property 7) Degree of modification (%) 88 86 86 82 85 84 81 82 84 85 (Physical property 8) Number of branches Bn when calculated per molecule 8.7 12.0 15.8 20.0 8.0 10.0 13.0 18.0 26.0 30.0 (Physical property 9) Change (ΔT) of the oxidation start temperature due to the application of heat load (°C) 9.2 8.8 9.3 9.5 8.9 8.7 9.1 9.3 8.7 9.0

[0214]

[Table 2]

Example 11 Example 12 Example 13 Example 14 Example 15 Example 16 Example 17 Example 18 Example 19 Example 20 Example 21 Modified polymer based on conjugated diene (sample no.) eleven 12 13 14 15 16 17 18 19 20 21 Polymerization conditions 1,3-butadiene (g/min) 13.0 13.0 13.0 13.0 13.0 13.0 12.0 10.0 8.0 15.0 13.0 Dissected portion of 1,3-butadiene (g/min) 5.6 5.6 5.6 5.6 5.6 5.6 6.6 8.6 10.6 3.6 5.6 Styrene (g/min) 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 n-hexane (g/min) 175.2 175.2 175.2 175.2 175.2 175.2 175.2 175.2 175.2 175.2 175.2 Polymerization temperature (°C) 70 70 70 70 70 70 70 70 70 70 70 n-butyllithium for decontamination of residual impurities (mmol/min) 0.103 0.103 0.103 0.103 0.103 0.103 0.103 0.103 0.103 0.103 0.103 n-butyllithium polymerization initiator (mmol/min) 0.143 0.143 0.143 0.143 0.143 0.143 0.143 0.143 0.143 0.143 0.143 Amount of added polar material (mmol/min) 0.081 0.081 0.081 0.081 0.081 0.081 0.081 0.081 0.081 0.081 0.081 Branching agent Type BS-4 BS-4 BS-4 BS-5 BS-5 BS-5 BS-1 BS-1 BS-1 BS-1 BS-1 Added quantity (mmol/min) 0.0210 0.0210 0.0210 0.0190 0.0190 0.0190 0.0190 0.0190 0.0190 0.0190 0.0190 Modifier Type A B C A B C A A A A D Added quantity (mmol/min) 0.0360 0.0250 0.0160 0.0360 0.0250 0.0160 0.0360 0.0360 0.0360 0.0360 0.0160 Physical Properties Conjugated diene based polymer (Physical property 3) Weight average molecular weight (10 ⁴ g/mol) 61.5 60.4 63.1 63.9 63.9 63.9 63.9 68.2 69.3 65.5 62.3 (Physical property 3) Number average molecular weight (10 ⁴ g/mol) 31.1 30.5 31.9 33.1 33.1 33.1 33.1 35.1 34.2 35.4 32.4 (Physical Property 5) Mooney Viscosity of Resin (110°C) 90.6 90.6 90.6 92.1 92.1 92.1 92.1 95.3 92.1 95.3 88.2 (Physical property 3) Mw/Mn 1.98 1.98 1.98 1.93 1.93 1.93 1.93 1.94 2.03 1.85 1.92 Modified polymer based on conjugated diene (Physical property 1) Amount of bound styrene (% (mass.)) 35 35 35 35 35 35 35 35 35 35 35 (Physical property 2) Amount of bonded vinyl (amount of 1,2-vinyl bond) (% (mol.)) 40 40 40 40 40 40 40 40 40 40 40 (Physical property 3) Weight average molecular weight (10 ⁴ g/mol) 91.0 94.0 102.3 92.0 96.0 105.3 105.3 103.5 105.0 101.3 102.5 (Physical property 3) Number average molecular weight (10 ⁴ g/mol) 46.0 47.2 54.1 47.2 48.7 54.3 53.5 52.5 54.4 53.6 50.5 (Physical property 3) Mw/Mn 1.98 1.99 1.89 1.95 1.97 1.94 1.97 1.97 1.93 1.89 2.03 (Physical property 4) Shrinkage ratio (g’) 0.51 0.41 0.35 0.52 0.40 0.32 0.32 0.50 0.42 0.55 0.65 (Physical Property 5) Mooney Viscosity of Resin (100°C) 82 83 84 83 83 83 83 83 82 80 85 (Physical property 6) Glass transition temperature (°C) - 23 - 23 - 23 - 23 - 23 - 23 - 23 - 23 - 23 - 23 - 23 (Physical property 7) Degree of modification (%) 82 84 58 88 86 86 86 80 82 83 0 (Physical property 8) Number of branches Bn when calculated per molecule 8.5 11.5 14.2 8.7 12.0 15.8 15.8 8.9 11.3 8.3 8.2 (Physical property 9) Change (ΔT) of the oxidation start temperature due to the application of heat load (°C) 8.8 8.6 9.2 9.5 8.3 8.6 7.6 4.7 3.8 3.6 9.1

[0215]

[Table 3]

Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Modified polymer based on conjugated diene (sample no.) 22 23 24 25 26 27 Polymerization conditions 1,3-butadiene (g/min) 15.0 17.2 18.6 13.0 13.0 13.0 Dissected portion of 1,3-butadiene (g/min) 3.6 1.4 0.0 5.6 5.6 5.6 Styrene (g/min) 10.0 10.0 10.0 10.0 10.0 10.0 n-hexane (g/min) 175.2 175.2 175.2 175.2 175.2 175.2 Polymerization temperature (°C) 70 70 70 70 70 70 n-butyllithium for decontamination of residual impurities (mmol/min) 0.103 0.103 0.103 0.103 0.103 0.103 n-butyllithium polymerization initiator (mmol/min) 0.143 0.143 0.143 0.143 0.143 0.143 Amount of added polar material (mmol/min) 0.081 0.081 0.081 0.081 0.081 0.081 Branching agent Type BS-1 BS-1 BS-1 - - - Added quantity (mmol/min) 0.0190 0.0190 0.0190 - - - Modifier Type A A A A B C Added quantity (mmol/min) 0.0360 0.0360 0.0360 0.0360 0.0250 0.0160 Physical Properties Conjugated diene based polymer (Physical property 3) Weight average molecular weight (10 ⁴ g/mol) 67.2 66.1 67.2 48.9 48.9 48.9 (Physical property 3) Number average molecular weight (10 ⁴ g/mol) 32.1 36.3 32.5 27.9 27.9 27.9 (Physical Property 5) Mooney Viscosity of Resin (110°C) 90.3 98.8 90.3 72.5 72.5 72.5 (Physical property 3) Mw/Mn 2.09 1.82 2.07 1.75 1.75 1.75 Modified polymer based on conjugated diene (Physical property 1) Amount of bound styrene (% (mass.)) 35 35 35 35 35 35 (Physical property 2) Amount of bonded vinyl (amount of 1,2-vinyl bond) (% (mol.)) 40 40 40 40 40 40 (Physical property 3) Weight average molecular weight (10 ⁴ g/mol) 105.2 103.4 104.2 82.1 94.3 117.4 (Physical property 3) Number average molecular weight (10 ⁴ g/mol) 53.9 52.2 54.0 40.8 47.9 59.3 (Physical property 3) Mw/Mn 1.95 1.98 1.93 2.01 1.97 1.98 (Physical property 4) Shrinkage ratio (g’) 0.53 0.52 0.55 0.91 0.74 0.56 (Physical Property 5) Mooney Viscosity of Resin (100°C) 81 88 81 75 83 96 (Physical property 6) Glass transition temperature (°C) - 23 - 23 - 23 - 23 - 23 - 23 (Physical property 7) Degree of modification (%) 81 85 58 83 86 80 (Physical property 8) Number of branches Bn when calculated per molecule 8.5 8.7 8.1 2.9 4.6 7.4 (Physical property 9) Change (ΔT) of the oxidation start temperature due to the application of heat load (°C) 12.0 14.3 15.5 9.5 9.3 9.2

[0216]

[Table 4]

Example 22 Example 23 Example 24 Example 25 Example 26 Example 27 Comparative Example 7 Comparative Example 8 Comparative Example 9 Modified polymer based on conjugated diene (sample no.) 28 29 thirty 31 32 33 34 35 36 Polymerization conditions 1,3-butadiene (g/min) 17.6 19.7 13.0 17.6 21.5 11.6 20.0 18.6 24.7 Dissected portion of 1,3-butadiene (g/min) 7.5 8.4 5.6 7.5 3.6 5.0 8.6 0.0 4.4 Styrene (g/min) 3.5 0.5 10.0 3.5 3.5 12.0 0.0 10.0 0.5 n-hexane (g/min) 175.2 175.2 175.2 175.2 175.2 175.2 175.2 175.2 175.2 Polymerization temperature (°C) 70 70 70 70 70 70 70 70 70 n-butyllithium for decontamination of residual impurities (mmol/min) 0.103 0.103 0.103 0.103 0.103 0.103 0.103 0.103 0.103 n-butyllithium polymerization initiator (mmol/min) 0.143 0.143 0.188 0.143 0.143 0.143 0.143 0.143 0.143 Amount of added polar material (mmol/min) 0.081 0.081 0.105 0.081 0.081 0.081 0.081 0.081 0.081 Branching agent Type BS-1 BS-1 BS-1 BS-1 BS-1 BS-1 BS-1 - BS-1 Added quantity (mmol/min) 0.0190 0.0190 0.0190 0.0190 0.0190 0.0190 0.0190 - 0.0190 Modifier Type C C C A C C C C C Added quantity (mmol/min) 0.0190 0.0190 0.0230 0.0360 0.0190 0.0190 0.0190 0.0190 0.0190 Physical Properties Conjugated diene based polymer (Physical property 3) Weight average molecular weight (10 ⁴ g/mol) 68.5 65.3 18.9 67.2 69.5 69.2 62.5 64.5 65.3 (Physical property 3) Number average molecular weight (10 ⁴ g/mol) 35.1 33.2 9.6 34.3 35.3 35.7 32.8 31.5 33.2 (Physical Property 5) Mooney Viscosity of Resin (110°C) 102.2 104.1 25 106.3 102.5 90.4 106.3 91.8 104.1 (Physical property 3) Mw/Mn 1.95 1.97 1.97 1.96 1.97 1.94 1.91 2.05 1.97 Modified polymer based on conjugated diene (Physical property 1) Amount of bound styrene (% (mass.)) 12 2 35 12 12 41 0 35 2 (Physical property 2) Amount of bonded vinyl (amount of 1,2-vinyl bond) (% (mol.)) 40 41 40 40 40 40 40 40 41 (Physical property 3) Weight average molecular weight (10 ⁴ g/mol) 104.2 103.0 27.2 105.3 105.3 95.3 100.2 110.3 103.0 (Physical property 3) Number average molecular weight (10 ⁴ g/mol) 55.2 56.2 13.5 53.4 56.2 50.2 52.3 54.5 56.2 (Physical property 3) Mw/Mn 1.89 1.83 2.01 1.97 1.87 1.90 1.92 2.02 1.83 (Physical property 4) Shrinkage ratio (g’) 0.33 0.35 0.52 0.51 0.34 0.37 0.35 0.57 0.35 (Physical Property 5) Mooney Viscosity of Resin (100°C) 90 92 53 94 91 87 95 85 92 (Physical property 6) Glass transition temperature (°C) - 55 - 67 - 23 - 55 - 55 - 17 - 70 - 23 - 67 (Physical property 7) Degree of modification (%) 83 80 86 81 82 80 81 88 80 (Physical property 8) Number of branches Bn when calculated per molecule 14.8 14.2 8.4 8.4 14.5 13.2 13.8 7.2 14.2 (Physical property 9) Change (ΔT) of the oxidation start temperature due to the application of heat load (°C) 9.5 11.3 9.0 11.2 11.5 5.5 15.2 15.0 13.5

[0217]

(Examples 28 to 54 and Comparative Examples 10 to 18)

Samples 1 to 36 shown in Tables 1 to 4 were used, respectively, as rubber raw materials to obtain rubber compositions containing, respectively, rubber raw materials in accordance with the following composition:

Conjugated Diene Modified Polymer (Samples 1 to 36 each): 100 parts by mass (excluding oil)

Silicon dioxide 1 (trade name "Ultrasil 7000GR", manufactured by Evonik Degussa, determined by nitrogen adsorption specific surface area: 170 m ² /g): 50.0 mass parts

Silicon dioxide 2 (trade name "Zeosil Premium 200MP", manufactured by Rhodia, nitrogen adsorption specific surface area: 220 m ² /g): 25.0 mass parts

Carbon black (trade name "Seast KH (N339)", manufactured by Tokai Carbon Co., Ltd.): 5.0 mass parts

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

S-RAE oil (trade name "Process NC140", manufactured by JX Nippon Oil & Energy Corporation): 37.5 mass parts

Zinc oxide: 2.5 mass parts

Stearic acid: 1.0 mass parts

Antioxidant (N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine): 2.0 mass parts

Sulfur: 2.2 mass parts

Vulcanization accelerator 1 (N-cyclohexyl-2-benzothiazylsulfinamide): 1.7 mass parts

Vulcanization accelerator 2 (diphenylguanidine): 2.0 mass parts

Total: 239.4 mass parts

[0218]

The materials described above were kneaded using the following method to obtain a rubber composition. For kneading, as the first stage of kneading, rubber raw material (each of samples from 1 to 27), fillers (silicon dioxide 1, silicon dioxide 2 and carbon black), silane coupling agent, process oil, zinc oxide and stearic acid, a closed kneader was used. machine (having an internal volume of 0.3 l) equipped with a temperature controller under conditions of a duty cycle of 65% and a rotor speed in the range of 30 to 50 rpm. In this case, the temperature of the closed kneader was adjusted to obtain each rubber composition (composition) at a discharge temperature in the range of 155 to 160°C.

[0219]

Subsequently, after cooling the composition obtained in accordance with the above description of the invention to room temperature, as the second stage of kneading, an antioxidant was added thereto, and the resulting product was kneaded again to improve the dispersibility of silica. Also in this case, the discharge temperature for the formulation was adjusted to a range of 155 to 160° C. using a mixer temperature controller. After cooling, sulfur and accelerators 1 and 2 were added as the third kneading stage, and the resulting product was kneaded using open rollers set at 70°C. Thereafter, the resulting product was molded and cured at 160° C. for 20 minutes using a curing press. Evaluated rubber composition before vulcanization and rubber composition after vulcanization. Specifically, the evaluations were carried out in accordance with the following description of the invention. The results are shown in tables 5 to 8.

[0220]

(Score 1) The Mooney Viscosity of the Composition

Each composition obtained after the second kneading stage and before the third kneading stage was used as a sample for measuring the viscosity using a Mooney viscometer in accordance with JIS K6300-1 after preheating the composition at 130°C for 1 minute and after rotating the rotor for for 4 minutes at 2 rpm. The viscosity thus obtained is shown as an index obtained under the assumption of taking the result from Comparative Example 10 as 100. A lower index indicates better processability.

[0221]

(Grade 2) Scorching

Each composition obtained after the second kneading stage and before the third kneading stage was used as a sample for measuring the scorch time under the test temperature condition of 130°C in accordance with JIS K6300-1. The scorch time thus obtained is shown as an index obtained under the assumption that the result of Comparative Example 10 is taken as 100. A larger index indicates a longer scorch time and more excellent heat resistance.

[0222]

(Score 3) Viscoelasticity parameter

To measure the viscoelasticity parameter in torsional mode, an "ARES" viscoelasticity testing machine manufactured by Rheometric Scientific, Inc. was used. 10 over 100. The tg δ value measured at 0° C. at a frequency of 10 Hz and a strain of 1% was used as an indicator of the wet grip performance of a tire. A higher value indicates better wet slip resistance. In addition, the tg δ value measured at 50° C. at a frequency of 10 Hz and a strain of 3% was used as an indicator of the low hysteresis loss characteristics. A lower value indicates better low hysteresis loss performance.

[0223]

(Grade 4) Abrasion resistance

The Acron abrasion tester (manufactured by Yasuda Seiki Seisakusho, Ltd.) was used to measure the amount of abrasion resulting from 1000 rotations under a load of 44.4 N according to JIS K6264-2, and the results are shown as indicators obtained from assumptions about accepting the result from the comparative example 10 over 100. A higher value indicates better abrasion resistance.

[0224]

[Table 5]

Example 28 Example 29 Example 30 Example 31 Example 32 Example 33 Example 34 Example 35 Example 36 Example 37 Modified Diene Based Polymer (Sample No.) 1 2 3 4 5 6 7 8 9 10 (Grade 1) Mooney Viscosity for Formulation (130°C) Index 83 85 80 78 84 85 78 78 78 78 (Grade 2) Scorching Index 105 105 105 105 105 105 105 105 105 105 (Grade 3) tg δ at 50°C (strain 3%) Index 80 75 70 73 82 83 73 73 75 77 (Grade 3) tg δ at 0°C (1% strain) Index 120 125 130 128 115 120 128 124 120 121 (Grade 4) Abrasion resistance Index 125 130 140 150 123 130 145 160 162 165

[0225]

[Table 6]

Example 38 Example 39 Example 40 Example 41 Example 42 Example 43 Example 44 Example 45 Example 46 Example 47 Example 48 Modified Diene Based Polymer (Sample No.) eleven 12 13 14 15 16 17 18 19 20 21 (Grade 1) Mooney Viscosity for Formulation (130°C) Index 89 87 82 86 85 80 82 72 68 75 88 (Grade 2) Scorching Index 105 105 105 105 105 105 110 112 115 120 104 (Grade 3) tg δ at 50°C (strain 3%) Index 85 80 90 80 75 70 70 83 85 80 105 (Grade 3) tg δ at 0°C (1% strain) Index 115 120 103 120 125 130 130 115 110 120 90 (Grade 4) Abrasion resistance Index 124 130 140 125 130 140 130 155 160 140 110

[0226]

[Table 7]

Comparative Example 10 Comparative Example 11 Comparative Example 12 Comparative Example 13 Comparative Example 14 Comparative Example 15 Modified Diene Based Polymer (Sample No.) 22 23 24 25 26 27 (Grade 1) Mooney Viscosity for Formulation (130°C) Index 100 98 94 112 108 103 (Grade 2) Scorching Index 100 95 90 108 108 108 (Grade 3) tg δ at 50°C (strain 3%) Index 100 90 85 70 70 70 (Grade 3) tg δ at 0°C (1% strain) Index 100 103 109 109 109 109 (Grade 4) Abrasion resistance Index 100 110 115 102 100 101

[0227]

[Table 8]

Example 49 Example 50 Example 51 Example 52 Example 53 Example 54 Comparative Example 16 Comparative Example 17 Comparative Example 18 Modified Diene Based Polymer (Sample No.) 28 29 thirty 31 32 33 34 35 36 (Grade 1) Mooney Viscosity for Formulation (130°C) Index 85 88 50 92 94 89 90 105 88 (Grade 2) Scorching Index 103 102 106 101 100 115 93 90 90 (Grade 3) tg δ at 50°C (strain 3%) Index 66 63 68 68 69 100 60 72 65 (Grade 3) tg δ at 0°C (1% strain) Index 105 102 128 104 104 100 100 110 101 (Grade 4) Abrasion resistance Index 140 144 105 133 135 105 148 148 140

[0228]

As shown in Tables 5 to 8, it was confirmed that Examples 28 to 54, compared with Comparative Examples 10 to 18, had an excellent balance between wet skid resistance and low hysteresis loss performance obtained when the material was in vulcanizate form, as well as excellent abrasion resistance.

It was also confirmed that they exhibited good heat resistance.

In addition, it was confirmed that they had a low Mooney viscosity for the composition when making a vulcanizate and showed good processability.

[0229]

This application is based on the earlier Japanese patent application (Japanese Patent Application No. 2019-144669) filed with the Japanese Patent Office on August 6, 2019, the entire contents of which are incorporated herein by reference.

Applicability in industry

[0230]

The conjugated diene-based polymer of the present invention can be industrially applied as a material and the like for tire treads, vehicle interior/exterior trim, anti-vibration rubbers, belts, shoes, foam bodies, and various industrial products.

Claims (88)

1. A conjugated diene-based polymer having a number of branches (Bn) measured according to light scattering measurement in a GPC method equipped with a viscosity detector, and being 8 or more, showing a change (ΔT) in the oxidation initiation temperature due to the application of a heat load of 11, 9° C. or less, and containing a monomeric aromatic vinyl compound unit. 2. The conjugated diene-based polymer according to claim 1, wherein the change (ΔT) in the oxidation start temperature due to the application of a heat load is 10° C. or less. 3. A polymer based on a conjugated diene according to claim 1 or 2, characterized by a degree of modification of 60% (wt.) or more. 4. A polymer based on a conjugated diene according to any one of paragraphs. 1-3, where the level of content of the monomeric elementary unit of the aromatic vinyl compound is 10% (wt.) or more. 5. A polymer based on a conjugated diene according to any one of paragraphs. 1-4, where the conjugated diene polymer is a conjugated diene polymer having a star polymer structure having 3 or more branches, at least one branched chain of the star-shaped polymer structure contains a segment derived from a vinyl-based monomer containing an alkoxysilyl group or a halosilyl group, and a segment derived from a vinyl-based monomer containing an alkoxysilyl group or a halosilyl group, in addition, has a structure with branching of the main chain. 6. A polymer based on a conjugated diene according to claim 5, where a site derived from a vinyl-based monomer containing an alkoxysilyl group or a halosilyl group is a monomeric elementary unit based on the compound described by the following formulas (1) or (2), and contains a branch point of a polymer chain containing a monomeric elementary unit on the basis of the compound described by formulas (1) or (2), and at least one end of the conjugated diene polymer is modified using a group containing a nitrogen atom:

, (1)

, (2) where in the formula (1) R ¹ represents a hydrogen atom, an alkyl group containing from 1 to 20 carbon atoms, or an aryl group containing from 6 to 20 carbon atoms, and may have a branched structure in its part; each of R ² and R ³ is independently an alkyl group of 1 to 20 carbon atoms or an aryl group of 6 to 20 carbon atoms, and may have a branched structure in part; each R ¹ to R ³ when present in the plural is, respectively, independent; X ¹ represents an independent halogen atom; A m is an integer in the range of 0 to 2, n is an integer in the range of 0 to 3, l is an integer in the range of 0 to 3, and (m+n+l) is 3; in the formula (2), each R ² to R ⁵ independently represents an alkyl group containing 1 to 20 carbon atoms or an aryl group containing 6 to 20 carbon atoms, and may have a branched structure in its part, and each from R ² to R ⁵ when present in the plural are, respectively, independent; X ² and X ³ represent an independent halogen atom; m is an integer in the range of 0 to 2, n is an integer in the range of 0 to 3, l is an integer in the range of 0 to 3, and (m+n+l) is 3; And a is an integer in the range 0 to 2, b is an integer in the range 0 to 3, c is an integer in the range 0 to 3, and (a+b+c) is 3. 7. A conjugated diene based polymer according to claim 6, containing a monomeric unit based on a compound represented by formula (1), where R ¹ is a hydrogen atom and m is 0. 8. A conjugated diene based polymer according to claim 6, containing a monomeric unit based on a compound represented by formula (2), where m is 0 and b is 0. 9. The conjugated diene-based polymer according to claim 6, containing a monomeric unit based on a compound represented by formula (1), where R ¹ is a hydrogen atom, m is 0, and l is 0. 10. The conjugated diene polymer according to claim 6, containing a monomeric unit based on the compound represented by formula (2), where m is 0, l is 0, a is 0, and b is 0. 11. A conjugated diene-based polymer according to claim 6, containing a monomeric elementary unit based on a compound represented by formula (1), where R ¹ is a hydrogen atom, l is 0, and n is 3. 12. A method for the production of a polymer based on a conjugated diene according to any one of paragraphs. 1-11, including: a polymerization/branching step in the form of polymerizing at least a conjugated diene compound in the presence of an organolithium-based compound to obtain a conjugated diene-based polymer having a backbone branching structure using a branching agent and a modifier containing a group containing a nitrogen atom, where the branching agent is a compound described by the following formulas (1) or (2):

, (1)

, (2) where in the formula (1) R ¹ represents a hydrogen atom, an alkyl group containing from 1 to 20 carbon atoms, or an aryl group containing from 6 to 20 carbon atoms, and may have a branched structure in its part; each of R ² and R ³ is independently an alkyl group of 1 to 20 carbon atoms or an aryl group of 6 to 20 carbon atoms, and may have a branched structure in part; each R ¹ to R ³ when present in the plural is, respectively, independent; X ¹ represents an independent halogen atom; m is an integer in the range of 0 to 2, n is an integer in the range of 0 to 3, l is an integer in the range of 0 to 3, and (m+n+l) is 3; in the formula (2), each R ² to R ⁵ independently represents an alkyl group containing 1 to 20 carbon atoms or an aryl group containing 6 to 20 carbon atoms, and may have a branched structure in its part, and each from R ² to R ⁵ when present in the plural are, respectively, independent; X ² and X ³ represent an independent halogen atom; m is an integer in the range of 0 to 2, n is an integer in the range of 0 to 3, l is an integer in the range of 0 to 3, and (m+n+l) is 3; And a is an integer in the range 0 to 2, b is an integer in the range 0 to 3, c is an integer in the range 0 to 3, and (a+b+c) is 3, where the modifier includes a modifier described by any one of the following formulas from (A) to (C):

, (A) where each R ¹ to R ⁴ independently represents an alkyl group containing from 1 to 20 carbon atoms, or an aryl group containing from 6 to 20 carbon atoms, R ⁵ represents an alkylene group containing from 1 to 10 carbon atoms, and R ⁶ is an alkylene group containing from 1 to 20 carbon atoms; and m is an integer of 1 or 2, n is an integer of 2 or 3, (m+n) is an integer of 4 or more, and each R ¹ to R ⁴ when plural is, respectively, independent;

, (B) where each R ¹ to R ⁶ independently represents an alkyl group containing from 1 to 20 carbon atoms, or an aryl group containing from 6 to 20 carbon atoms, and each from R ⁷ to R ⁹ independently represents an alkylene group containing from 1 to 20 carbon atoms; and each m, n and l is independently an integer in the range of 1 to 3, (m+n+l) is an integer of 4 or more, and each R ¹ to R ⁶ when plural is, accordingly, independent;

, (C) where each R ¹² to R ¹⁴ independently represents a single bond or an alkylene group containing from 1 to 20 carbon atoms, each from R ¹⁵ to R ¹⁸ and R ²⁰ independently represents an alkyl group containing from 1 to 20 carbon atoms, each of R ¹⁹ and R ²² is independently an alkylene group having 1 to 20 carbon atoms, R ²¹ is an alkyl group or a trialkylsilyl group having 1 to 20 carbon atoms; m is an integer ranging from 1 to 3 and p is 1 or 2; each R ¹² to R ²² , m and p, if present in the plural, are respectively independent and may be identical to or different from the others; i is an integer in the range 0 to 6, j is an integer in the range 0 to 6, k is an integer in the range 0 to 6, a (i+j+k) is an integer in the range from 4 to 10; and A is a hydrocarbon group containing 1 to 20 carbon atoms, or an organic group containing 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 not containing active hydrogen atom. 13. A method for producing a conjugated diene based polymer according to any one of claims 1 to 11, comprising: a step of polymerizing a conjugated diene compound and an aromatic vinyl compound in the presence of an organolithium-based compound to obtain a copolymer; a step of reacting a copolymer of a conjugated diene compound and an aromatic vinyl compound and a vinyl-based monomer containing an alkoxysilyl group or a halosilyl group to obtain a branched main chain structure; And a step of polymerizing a polymer chain having a backbone branching structure with at least a conjugated diene compound, and the stage of modifying the polymer based on the conjugated diene using a modifier containing a group containing a nitrogen atom, where the vinyl-based monomer containing an alkoxysilyl group is represented by the following formulas (1) or (2):

, (1)

, (2) where in the formula (1) R ¹ represents a hydrogen atom, an alkyl group containing from 1 to 20 carbon atoms, or an aryl group containing from 6 to 20 carbon atoms, and may have a branched structure in its part; each of R ² and R ³ is independently an alkyl group of 1 to 20 carbon atoms or an aryl group of 6 to 20 carbon atoms, and may have a branched structure in part; each R ¹ to R ³ when present in the plural is, respectively, independent; X ¹ represents an independent halogen atom; A m is an integer in the range of 0 to 2, n is an integer in the range of 1 to 3, l is an integer in the range of 0 to 3, and (m+n+l) is 3; in the formula (2), each R ² to R ⁵ independently represents an alkyl group containing 1 to 20 carbon atoms or an aryl group containing 6 to 20 carbon atoms, and may have a branched structure in its part, and each from R ² to R ⁵ when present in the plural are, respectively, independent; X ² and X ³ represent an independent halogen atom; m is an integer in the range of 0 to 2, n is an integer in the range of 0 to 3, l is an integer in the range of 0 to 3, and (m+n+l) is 3; And a is an integer in the range 0 to 2, b is an integer in the range 0 to 3, c is an integer in the range 0 to 3, and (a+b+c) is 3, and where the modifier includes a modifier described by any one of the following formulas from (A) to (C):

, (A) where each R ¹ to R ⁴ independently represents an alkyl group containing from 1 to 20 carbon atoms, or an aryl group containing from 6 to 20 carbon atoms, R ⁵ represents an alkylene group containing from 1 to 10 carbon atoms, and R ⁶ is an alkylene group containing from 1 to 20 carbon atoms; and m is an integer of 1 or 2, n is an integer of 2 or 3, (m+n) is an integer of 4 or more, and each R ¹ to R ⁴ when plural is, respectively, independent;

, (B) where each R ¹ to R ⁶ independently represents an alkyl group containing from 1 to 20 carbon atoms, or an aryl group containing from 6 to 20 carbon atoms, and each from R ⁷ to R ⁹ independently represents an alkylene group containing from 1 to 20 carbon atoms; and each m, n and l is independently an integer in the range of 1 to 3, (m+n+l) is an integer of 4 or more, and each R ¹ to R ⁶ when plural is, accordingly, independent;

, (C) where each R ¹² to R ¹⁴ independently represents a single bond or an alkylene group containing from 1 to 20 carbon atoms, each from R ¹⁵ to R ¹⁸ and R ²⁰ independently represents an alkyl group containing from 1 to 20 carbon atoms, each of R ¹⁹ and R ²² is independently an alkylene group having 1 to 20 carbon atoms, R ²¹ is an alkyl group or a trialkylsilyl group having 1 to 20 carbon atoms; m is an integer ranging from 1 to 3 and p is 1 or 2; each R ¹² to R ²² , m and p, if present in the plural, are respectively independent and may be identical to or different from the others; i is an integer in the range 0 to 6, j is an integer in the range 0 to 6, k is an integer in the range 0 to 6, a (i+j+k) is an integer in the range from 4 to 10; and A is a hydrocarbon group containing 1 to 20 carbon atoms, or an organic group containing 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 not containing active hydrogen atom. 14. A process for the production of a conjugated diene-based polymer according to claim 12 or 13, wherein formula (C) A describes any one of the following general formulas from (II) and (V):

, (II) where In ¹ represents a single bond or a hydrocarbon group containing from 1 to 20 carbon atoms, and represents an integer in the range from 1 to 10, and In ¹ when present in the plural is, respectively, independent;

, (III) where B ² represents a single bond or a hydrocarbon group containing from 1 to 20 carbon atoms, B ³ represents an alkyl group containing from 1 to 20 carbon atoms, and represents an integer in the range from 1 to 10 and each of B ² and B ³ , if present in the plural, is, respectively, independent;

,(IV) where B ⁴ represents a single bond or a hydrocarbon group containing from 1 to 20 carbon atoms, and represents an integer in the range from 1 to 10 and B ⁴ when present in the plural is, respectively, independent;

, (V) where B ⁵ represents a single bond or a hydrocarbon group containing from 1 to 20 carbon atoms, and represents an integer in the range from 1 to 10 and B ⁵ when present in the plural is, respectively, independent. 15. An oil-filled polymer based on a conjugated diene, containing: 100 wt.h. polymer based conjugated diene according to any one of paragraphs. 1-11; And from 1 to 60 wt.h. filling oils. 16. Rubber composition for obtaining vulcanized rubber, containing: rubber component; And from 5.0 wt.h. and more up to 150 wt.h. and less filler when calculated per 100 wt.h. rubber component where the rubber component contains, based on the total amount of the rubber component, 10% (wt.) or more of a polymer based on a conjugated diene according to any one of paragraphs. 1-11 or an oil-filled polymer based on a conjugated diene according to claim 15. 17. A tire containing a rubber composition according to claim 16.