Conjugated diene polymer, method for manufacturing a conjugated diene polymer, and rubber composition

Abstract

A conjugated diene polymer satisfying the following conditions (1) to (5). (1) The molecular weight distribution curve obtained by gel permeation chromatography (GPC) measurement is monomodal and has a shoulder in the region from the peak top of the molecular weight distribution curve to the peak end point on the high molecular weight side. (2) The weight-average molecular weight (Mw) measured by GPC is 200,000 to 1,000,000. (3) The molecular weight distribution is 1.7 to 3.0. (4) The rate of modification is less than 40 mass%. (5) When the absolute molecular weight curve is measured by the GPC-light scattering method equipped with a viscosity detector, in the region on the high molecular weight side rather than the peak top, the absolute molecular weight at the first inflection point is Mw1 and the absolute molecular weight at the peak end point is Mw2, and the degree of branching (Bn) at the absolute molecular weight of (Mw1+Mw2) / 2 is 4 or more. (6) The shrinkage factor (g') in the peak top molecular weight (Mp) obtained by the GPC-light scattering measurement method equipped with a viscosity detector is 0.90 or higher.

Description

Technology Field

[0001] The present invention relates to a conjugated diene polymer, a method for manufacturing a conjugated diene polymer, and a rubber composition. Background Technology

[0002] Since the demand for lower fuel consumption in automobiles has been increasing, there is a demand for improvements in materials used in automobile tires, particularly in tire treads that come into contact with the ground.

[0003] In recent years, there has been a demand for the development of materials with low rolling resistance, that is, low hysteresis loss.

[0004] In addition, to lighten the weight of the tire, it is necessary to reduce the thickness of the tire tread, and materials with high wear resistance are also required.

[0005] On the other hand, materials used for tire treads are required to have excellent wet skid resistance and sufficient fracture characteristics for practical use from the perspective of safety.

[0006] As a rubber material that meets the requirements described above, examples include a rubbery polymer and a reinforcing filler such as carbon black and silica.

[0007] By using rubber materials containing silica, it is possible to improve the balance between low hysteresis loss and wet skid resistance. In addition, attempts are being made to improve wear resistance while reducing hysteresis loss by introducing functional groups having affinity or reactivity with silica into the molecular ends of highly mobile rubbery polymers, thereby improving the dispersibility of silica within the rubber material, or further reducing the mobility of the molecular ends of the rubbery polymers through bonding with silica particles.

[0008] As the above rubbery polymer, a modified conjugated diene polymer is used, and for example, Patent Documents 1 to 3 propose a composition of silica and a modified conjugated diene polymer obtained by reacting an alkoxysilane containing an amino group with the active end of a conjugated diene polymer.

[0009] In addition, Patent Document 4 proposes a modified conjugated diene polymer obtained by coupling a polymer active end with a polyfunctional silane compound.

[0010] In addition, regarding the above rubbery polymer, high molecular weight of the conjugated diene polymer is being increased in order to improve wear resistance.

[0011] However, high molecular weight conjugated diene polymers have a problem in that there is room for improvement in the working environment, as polymer particles are prone to peeling off from the surface of the bale itself and contaminating the area around the molding machine or the conveyor used to transport the bale after molding with polymer particles. Furthermore, since the increase in molecular weight of conjugated diene polymers entails an increase in the viscosity of the composition, it is prone to causing poor dispersion of reinforcing fillers such as carbon black and silica during kneading, leaving room for improvement from the perspective of processability as well. When such materials are vulcanized, particularly when the resulting product contains inorganic fillers such as silica, the low hysteresis loss and wear resistance are insufficient.

[0012] As a method to prevent such high molecular weight conjugated diene polymers from peeling off from the surface of the veil, a method of adding process oil can be cited.

[0013] For example, Patent Document 5 discloses a method for suppressing the peeling and detachment of polymer particles from the surface of a veil by adding process oil to a solution of a conjugated diene polymer and making it an oil-conjugated diene polymer. Prior art literature

[0014] Japanese Patent Publication No. 2005-290355, Japanese Patent Publication No. Hei 11-189616, Japanese Patent Publication No. 2003-171418, International Publication No. 07 / 114203 Pamphlet, Japanese Patent Publication No. 2019-131810 The problem to be solved

[0015] When a functional group highly reactive with silica is introduced to the molecular ends of a conjugated diene polymer, there is a problem in that the processability tends to deteriorate, such as the reaction with silica particles proceeds during the mixing process, causing the viscosity of the composition to increase, making it difficult to mix, or surface roughness occurring or sheet breakage occurring when forming it into a sheet after mixing.

[0016] In addition, when such a composition is used as a vulcanized product, especially when it is used as a vulcanized product containing inorganic fillers such as silica, there is a problem of reduced hardness due to excessive dispersion of silica or insufficient wear resistance.

[0017] In addition, regarding the improvement of wear resistance, when conjugated diene polymers are increased in molecular weight, it is common to use oil-containing conjugated diene polymers with added process oil to improve bale moldability or processability after mixing; however, in recent years, there has been a desire to reduce the amount of process oil added to conjugated diene polymers as much as possible to improve the freedom of formulation when producing rubber compositions.

[0018] However, in the case of the conjugated diene polymer bale disclosed in Patent Document 5, there is a problem in that sufficient moldability is not obtained when the amount of process oil added is reduced.

[0019] For example, if the molecular weight of a conjugated diene polymer is increased to improve wear resistance, or if the glass transition temperature of the conjugated diene polymer is set low to improve low hysteresis loss, and the amount of process oil added is small or the formulation does not contain process oil, polymer particles are prone to peeling off from the surface of the bale. Furthermore, such conjugated diene polymers have the problem that the viscosity of the composition increases during kneading, thereby deteriorating processability.

[0020] Therefore, the present invention aims to provide a conjugated diene polymer that, even if it is a non-genetic product that does not add process oil, has excellent bale moldability and good processability when vulcanized, and when mixed with a filler, the torque of the mixer is well applied so that the filler can be properly dispersed, thereby obtaining a rubber composition with high hardness and good wear resistance when vulcanized. means of solving the problem

[0021] The inventors, as a result of careful consideration to solve the above problem, discovered that a conjugated diene polymer, in which the molecular weight distribution curve obtained by gel permeation chromatography (GPC) measurement is monomodal with a shoulder on the high molecular weight side, has a predetermined weight average molecular weight (Mw), molecular weight distribution, and modification rate, and the degree of branching in the high molecular weight side region is greater than a predetermined value, has excellent processability when vulcanized, high hardness when vulcanized, and good wear resistance, and thus completed the present invention.

[0022] That is, the present invention is as follows.

[0023] [1]

[0024] A conjugated diene polymer satisfying the following conditions (1) to (6).

[0025] (1) The molecular weight distribution curve obtained by gel permeation chromatography (GPC) measurement is monomodal and has a shoulder in the region from the peak top of the molecular weight distribution curve to the peak end point on the high molecular weight side.

[0026] (2) The weight-average molecular weight (Mw) measured by GPC is 200,000 to 1,000,000.

[0027] (3) The molecular weight distribution is 1.7 to 3.0.

[0028] (4) The rate of modification is less than 40 mass%.

[0029] (5) When the absolute molecular weight curve is measured by the GPC-light scattering method equipped with a viscosity detector, in the region on the high molecular weight side rather than the peak top, the absolute molecular weight at the first inflection point is Mw1 and the absolute molecular weight at the peak end point is Mw2, and the degree of branching (Bn) at the absolute molecular weight of (Mw1+Mw2) / 2 is 4 or more.

[0030] (6) The shrinkage factor (g') in the peak top molecular weight (Mp) obtained by the GPC-light scattering measurement method equipped with a viscosity detector is 0.90 or higher.

[0031] [1-1A]

[0032] A conjugated diene polymer described in [1] having 1 to 5 shoulders.

[0033] [1-1B]

[0034] A conjugated diene polymer described in [1] or [1-1A] having 1 to 4 shoulders.

[0035] [1-1C]

[0036] A conjugated diene polymer described in any one of [1] to [1-1B], having 1 to 3 shoulders.

[0037] [1-1D]

[0038] A conjugated diene polymer described in any one of [1] to [1-1C] having 1 to 2 shoulders.

[0039] [1-1E]

[0040] A conjugated diene polymer described in any one of [1] to [1-1D] having 1 shoulder.

[0041] [1-2A]

[0042] A conjugated diene polymer described in any one of [1] to [1-1E], having a weight average molecular weight (Mw) of 300,000 to 900,000.

[0043] [1-2B]

[0044] A conjugated diene polymer described in any one of [1] to [1-2A], having a weight average molecular weight (Mw) of 400,000 to 800,000.

[0045] [1-3A]

[0046] A conjugated diene polymer described in any one of [1] to [1-2B] having a molecular weight distribution of 1.75 to 2.8.

[0047] [1-3B]

[0048] A conjugated diene polymer described in any one of [1] to [1-3A] having a molecular weight distribution of 1.8 to 2.8.

[0049] [1-3C]

[0050] A conjugated diene polymer described in any one of [1] to [1-3B] having a molecular weight distribution of 1.85 to 2.5.

[0051] [1-3D]

[0052] A conjugated diene polymer described in any one of [1] to [1-3C] having a molecular weight distribution of 1.9 to 2.5.

[0053] [1-4A]

[0054] A conjugated diene polymer described in any one of [1] to [1-3D], having a modification rate of 30 mass% or less.

[0055] [1-4B]

[0056] A conjugated diene polymer described in any one of [1] to [1-4A], having a modification rate of 20 mass% or less.

[0057] [1-4C]

[0058] A conjugated diene polymer described in any one of [1] to [1-4B], having a modification rate of 10 mass% or less.

[0059] [1-5A]

[0060] A conjugated diene polymer described in any one of [1] to [1-4C], wherein the degree of branching (Bn) is 4 to 84.

[0061] [1-5B]

[0062] A conjugated diene polymer described in any one of [1] to [1-5A], having a branching degree (Bn) of 4 to 80.

[0063] [1-5C]

[0064] A conjugated diene polymer described in any one of [1] to [1-5B], having a branching degree (Bn) of 5 to 60.

[0065] [1-5D]

[0066] A conjugated diene polymer described in any one of [1] to [1-5C], having a branching degree (Bn) of 5 to 40.

[0067] [1-5E]

[0068] A conjugated diene polymer described in any one of [1] to [1-5D], having a branching degree (Bn) of 6 to 20.

[0069] [1-6A]

[0070] A conjugated diene polymer described in any one of [1] to [1-5E], having a shrinkage factor (g') of 0.91 or more at the peak top molecular weight (Mp) above.

[0071] [1-6B]

[0072] A conjugated diene polymer described in any one of [1] to [1-6A], having a shrinkage factor (g') of 0.92 or more at the peak top molecular weight (Mp) above.

[0073] [1-6C]

[0074] A conjugated diene polymer described in any one of [1] to [1-6B], wherein the shrinkage factor (g') at the peak top molecular weight (Mp) is 2.00 or less.

[0075] [1-6D]

[0076] A conjugated diene polymer described in any one of [1] to [1-6C], wherein the shrinkage factor (g') at the peak top molecular weight (Mp) is 1.50 or less.

[0077] [1-6E]

[0078] A conjugated diene polymer described in any one of [1] to [1-6D], wherein the shrinkage factor (g') at the peak top molecular weight (Mp) is 1.00 or less.

[0079] [2]

[0080] A conjugated diene polymer described in any one of [1] to [1-6E], having a shrinkage factor (g') of 0.90 or more in the number average molecular weight (Mn) obtained by a GPC-light scattering measurement method equipped with a viscosity detector.

[0081] [2-1A]

[0082] A conjugated diene polymer described in any one of [1] to [2], having a shrinkage factor (g') of 0.91 or more in the number average molecular weight (Mn) above.

[0083] [2-1B]

[0084] A conjugated diene polymer described in any one of [1] to [2-1A], having a shrinkage factor (g') of 0.92 or more in the number average molecular weight (Mn) above.

[0085] [2-1C]

[0086] A conjugated diene polymer described in any one of [1] to [2-1B], wherein the shrinkage factor (g') in the number average molecular weight (Mn) is 2.00 or less.

[0087] [2-1D]

[0088] A conjugated diene polymer described in any one of [1] to [2-1C], having a shrinkage factor (g') of 1.50 or less in the number average molecular weight (Mn) above.

[0089] [2-1E]

[0090] A conjugated diene polymer described in any one of [1] to [2-1D], wherein the shrinkage factor (g') in the number average molecular weight (Mn) is 1.00 or less.

[0091] [2-2A]

[0092] A conjugated diene polymer described in any one of [1] to [2-1E], wherein the shrinkage factor (g') at the peak top molecular weight (Mp) of the absolute molecular weight curve and the shrinkage factor (g') at the number average molecular weight (Mn) are 0.90 or higher.

[0093] [2-2B]

[0094] A conjugated diene polymer described in any one of [1] to [2-2A], wherein the shrinkage factor (g') at the peak top molecular weight (Mp) of the absolute molecular weight curve and the shrinkage factor (g') at the number average molecular weight (Mn) are 0.91 or higher.

[0095] [2-2C]

[0096] A conjugated diene polymer described in any one of [1] to [2-2B], wherein the shrinkage factor (g') at the peak top molecular weight (Mp) of the absolute molecular weight curve and the shrinkage factor (g') at the number average molecular weight (Mn) are 0.92 or higher.

[0097] [2-3A]

[0098] A conjugated diene polymer described in any one of [1] to [2-2C], wherein the shrinkage factor (g') at the peak top molecular weight (Mp) of the absolute molecular weight curve and the shrinkage factor (g') at the number average molecular weight (Mn) are 0.90 or more and 2.00 or less.

[0099] [2-3B]

[0100] A conjugated diene polymer described in any one of [1] to [2-3A], wherein the shrinkage factor (g') at the peak top molecular weight (Mp) of the absolute molecular weight curve and the shrinkage factor (g') at the number average molecular weight (Mn) are 0.91 or higher and 1.50 or lower.

[0101] [2-3C]

[0102] A conjugated diene polymer described in any one of [1] to [2-3B], wherein the shrinkage factor (g') at the peak top molecular weight (Mp) of the absolute molecular weight curve and the shrinkage factor (g') at the number average molecular weight (Mn) are 0.92 or higher and 1.00 or lower.

[0103] [3]

[0104] A conjugated diene polymer described in any one of [1] to [2-3C], having a modification rate of less than 10 mass%.

[0105] [3-1]

[0106] A conjugated diene polymer described in [3] having a modification rate of 5 mass% or less.

[0107] [3-2]

[0108] A conjugated diene polymer described in [3] or [3-1] having a modification rate of 0 mass%.

[0109] [4]

[0110] A conjugated diene polymer described in any one of [1] to [3-2], comprising a conjugated diene polymer (A) having an Mw of 500,000 to 3,000,000 as measured by GPC, and a conjugated diene polymer (B) having an Mw of 100,000 to 500,000 as measured by GPC.

[0111] [5]

[0112] A conjugated diene polymer described in [4], wherein the difference in Mw (ΔMw) between the above conjugated diene polymer (A) and the above conjugated diene polymer (B) is 200,000 or more.

[0113] [6]

[0114] A conjugated diene polymer described in [4] or [5], wherein the mass ratio ((A) / (B)) of the conjugated diene polymer (A) and the conjugated diene polymer (B) is 10 / 90 to 40 / 60.

[0115] [7]

[0116] [4] A method for manufacturing a conjugated diene polymer as described in any one of [4] to [6],

[0117] The above conjugated diene polymer (A) and the above conjugated diene polymer (B) are each obtained by continuous polymerization using one or more reactors, and

[0118] A polymer solution containing the conjugated diene polymer (A) and a polymer solution containing the conjugated diene polymer (B) are mixed as a solution.

[0119] Subsequently, the solvent is removed to obtain a conjugated diene polymer, comprising

[0120] Method for manufacturing a conjugated diene polymer.

[0121] [8]

[0122] 100 parts by mass of a conjugated diene polymer described in any of [1] to [6], and

[0123] 2.0 parts by mass or less of organic acid

[0124] A molded body comprising

[0125] [8-1]

[0126] A molded body described in [8] having a content of 0.01 to 2.0 parts by mass of the above organic acid.

[0127] [8-2]

[0128] A molded body described in [8] or [8-1] having a content of 0.02 to 1.5 parts by mass of the above organic acid.

[0129] [8-3]

[0130] A molded body described in any one of [8] to [8-2], having a content of 0.03 to 1.0 mass parts of the above organic acid.

[0131] [8-4]

[0132] A molded body described in any one of [8] to [8-3], having a content of 0.04 to 0.5 parts by mass of the above organic acid.

[0133] [9]

[0134] 100 parts by mass of a rubber component comprising a conjugated diene polymer as described in any one of [1] to [6], and

[0135] Filler 20 parts by mass or more, 150 parts by mass or less

[0136] A rubber composition comprising Effects of the invention

[0137] According to the present invention, a conjugated diene polymer is obtained that has excellent bale formability even in a non-genetic product that does not add process oil, excellent processability when vulcanized, high hardness when vulcanized, and excellent wear resistance. Specific details for implementing the invention

[0138] Hereinafter, a form for carrying out the present invention (hereinafter referred to as "the present embodiment") will be described in detail.

[0139] Furthermore, the following embodiments are examples for explaining the present invention, and the present invention is not limited to the following embodiments but can be implemented with various modifications within the scope of the gist thereof.

[0140] [Conjugated diene polymers]

[0141] The conjugated diene polymer of the present embodiment is,

[0142] The molecular weight distribution curve obtained by gel permeation chromatography (GPC) measurement is unimodal and has a shoulder in the region from the peak top of the molecular weight distribution curve to the peak endpoint on the high molecular weight side,

[0143] The weight-average molecular weight (Mw) measured by GPC is 200,000 to 1,000,000, and

[0144] The molecular weight distribution is 1.7 or greater and 3.0 or less, and

[0145] With respect to the total amount of conjugated diene polymer, the modification rate is less than 40 mass%, and

[0146] In the region on the high molecular weight side relative to the peak top in the absolute molecular weight curve measured by the GPC-light scattering method equipped with a viscosity detector, when the absolute molecular weight at the first inflection point is Mw1 and the absolute molecular weight at the peak end point is Mw2, the degree of branching (Bn) at the absolute molecular weight of (Mw1+Mw2) / 2 is 4 or greater,

[0147] It is a conjugated diene polymer.

[0148] The conjugated diene polymer of the present embodiment may be any of a homopolymer of a single conjugated diene compound, a polymer of other types of conjugated diene compounds, i.e., a copolymer, or a copolymer of a conjugated diene compound and a vinyl aromatic compound.

[0149] Examples of conjugated diene compounds include, but are not limited to the following: 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 3-methyl-1,3-pentadiene, 1,3-hexadiene, and 1,3-heptadiene. Among these, 1,3-butadiene and isoprene are preferred from the view that the effects of the present embodiment are effectively and reliably exhibited. These conjugated diene compounds may be used as a single type or in combination of two or more types.

[0150] In addition, vinyl aromatic compounds are not limited to the following, but examples include styrene, p-methylstyrene, m-methylstyrene, o-methylstyrene, α-methylstyrene, vinylethylbenzene, vinylxylene, vinylnaphthalene, and diphenylethylene. Among these, styrene is preferred from the view that it effectively and reliably exhibits the effects of the present embodiment. These vinyl aromatic compounds may be used as a single type or in combination of two or more types.

[0151] Conjugated diene polymers may be random copolymers or block copolymers.

[0152] Examples of random copolymers include, but are not limited to the following: a random copolymer containing two or more conjugated diene compounds such as butadiene-isoprene random copolymer, butadiene-styrene random copolymer, isoprene-styrene random copolymer, and a random copolymer containing a vinyl-substituted aromatic compound with a conjugated diene of butadiene-isoprene-styrene random copolymer.

[0153] The compositional distribution of each monomer in the copolymer chain is not particularly limited, and examples include a completely random copolymer with a composition close to statistically random, and a tapered random copolymer with a composition distributed in a tapered shape. The composition of the conjugated diene bonding pattern, such as 1,4-links or 1,2-links, may be uniform or distributed.

[0154] (Molecular weight distribution curve of conjugated diene polymers)

[0155] The conjugated diene polymer of the present embodiment is characterized by a molecular weight distribution curve obtained by measuring by gel permeation chromatography (GPC) analysis, which is unimodal and has a shoulder in the region from the peak top of the molecular weight distribution curve to the peak end point on the high molecular weight side. Here, "the molecular weight distribution curve is unimodal and has a shoulder in the region from the peak top of the molecular weight distribution curve to the peak end point on the high molecular weight side" means that in the molecular weight distribution curve, there is one peak top and three or more inflection points between the peak start point and the peak end point, and also two or more inflection points exist in the region from the peak top to the peak end point, that is, in the region from the peak top to the high molecular weight side.

[0156] When the number of shoulders is n, the number of inflection points is calculated from the formula 2n+1, and in the conjugated diene polymer of the present embodiment, there are one or more shoulders and three or more inflection points in the region from the peak top to the high molecular weight side.

[0157] The upper limit of the shoulder number is not specifically limited, but it may be, for example, 5, 4, 3, or 2.

[0158] When such a molecular weight distribution curve is exhibited, the following reasons may be cited as factors for having good bale formability, excellent processability when vulcanized, and good wear resistance when vulcanized, but are not limited to the reasons described below.

[0159] Generally, the wear resistance and fracture strength of a polymer are superior as the molecular weight increases, but at the same time, polymer particles tend to peel off easily from the surface of the veil, which tends to worsen veil formability.

[0160] Furthermore, when mixing polymers and fillers, within the molecular weight range where mixing is possible, the higher the molecular weight of the polymer, the better the torque of the mixer is applied, and the easier it is to disperse the filler. On the other hand, due to the increase in the viscosity of the composition, there is a tendency for processability to deteriorate, such as making mixing difficult, or causing surface roughness or sheet breakage when forming into sheets after mixing.

[0161] The conjugated diene polymer of the present embodiment is characterized by having a molecular weight distribution curve that is monomodal and has a shape with a shoulder in the region from the peak top of the molecular weight distribution curve to the peak end point on the high molecular weight side. While containing a high molecular weight component (referred to as "Component A"), the bale moldability is excellent by mainly using a component with a lower molecular weight than that component (referred to as "Component B"). In addition, the processability is excellent because Component A improves the torque of the mixer when kneading with the filler and properly disperses the filler, and Component B lowers the viscosity of the composition. When made into a vulcanized product, the wear resistance is excellent due to the inclusion of Component A, which is a high molecular weight component, and the proper dispersion of the filler.

[0162] A conjugated diene polymer having a molecular weight distribution curve that is monomodal and has a shoulder in the region from the peak top of the molecular weight distribution curve to the peak endpoint on the high molecular weight side is obtained by mixing a polymer containing components with different molecular weights or degrees of branching, with the view that the balance between molecular weight and viscosity falls within an appropriate range. Specifically, as described below, it is obtained by adjusting the molecular weights or degrees of branching of component A and component B, or by adjusting their ratios. As a result, it can have good bale formability, excellent processability when vulcanized, high hardness when vulcanized, and good wear resistance.

[0163] (Average molecular weight and molecular weight distribution of conjugated diene polymers)

[0164] The conjugated diene polymer of the present embodiment preferably has a weight-average molecular weight of 20×10 as measured by GPC. 4 This is the extent, and more preferably 30×10 4 That is all, and more preferably 40×10 4 That is all. The weight-average molecular weight measured by the GPC method is 20×10 4 If the above is the case, the torque of the mixer is applied well when kneading with the filler, and there is a tendency for the filler to be easily dispersed. In addition, the weight average molecular weight is preferably 100×10 4 Less than, and more preferably 90×10 4 Less than, and more preferably 80×10 4 It is less than or equal to. The weight-average molecular weight is 100×10 4 If it is below this level, the viscosity of the rubber composition when mixed with the filler does not become too high, and the processability tends to be excellent.

[0165] The weight-average molecular weight may be within a range obtained by arbitrarily combining the upper and lower limits mentioned above.

[0166] The weight average molecular weight of a conjugated diene polymer can be measured by the method described in the examples below.

[0167] The conjugated diene polymer of the present embodiment preferably has a number average molecular weight of 6×10⁻⁶ as measured by GPC. 4 This is the extent, and more preferably 9×10 4 This is the ideal, and more preferably 12×10 4 That is all. The number-average molecular weight mentioned above is 15×10 4 It is acceptable to be greater than 6×10 4 If the above, the torque of the mixer is well applied when kneading with the filler, and the filler tends to be easily dispersed. In addition, the number average molecular weight is preferably 60×10 4 Less than or equal to, and more preferably 50×10 4Less than, and more preferably 45×10 4 Less than, and more preferably 40×10 4 Less than, and more preferably 35×10 4 Less than or equal to, and most preferably 30×10 4 It is less than or equal to the number average molecular weight of 60×10 4 If it is below this level, the viscosity of the rubber composition when mixed with the filler does not become too high, and the processability tends to be excellent.

[0168] The number average molecular weight may be within a range obtained by arbitrarily combining the upper and lower limits mentioned above.

[0169] The number average molecular weight of a conjugated diene polymer can be measured by the method described in the examples below.

[0170] In the conjugated diene polymer of the present embodiment, the ratio of the weight-average molecular weight (Mw) measured by GPC to the number-average molecular weight (Mn) measured by GPC (Molecular weight distribution) (Mw / Mn) is preferably 1.7 or higher, more preferably 1.75 or higher, even more preferably 1.8 or higher, even more preferably 1.85 or higher, and most preferably 1.9 or higher, in terms of processability during vulcanization and wear resistance of the vulcanized product. The upper limit of the molecular weight distribution is not particularly limited, but is preferably 3.0 or lower, more preferably 2.8 or lower, and even more preferably 2.5 or lower.

[0171] As described below, the molecular weight distribution of the conjugated diene polymer can be controlled to the above numerical range by adjusting the ratio of the molecular weights or branches of components A and B.

[0172] (Voice change)

[0173] The conjugated diene polymer of the present embodiment may have a modifying group.

[0174] "Modifying group" refers to a functional group having affinity or binding reactivity to the filler, and may include a functional group containing a nitrogen atom.

[0175] (Degeneration rate)

[0176] In this specification, "modification rate" refers to the content ratio, expressed in mass %, of a modified conjugated diene polymer component having a specific functional group having affinity or binding reactivity to a filler within the polymer molecule, relative to the total amount of the mixture of conjugated diene polymers, in cases where a mixture of a modified conjugated diene polymer and an unmodified conjugated diene polymer is obtained by modifying a conjugated diene polymer with a coupling modifier. Accordingly, when the specific functional group contains a nitrogen atom, it represents the mass ratio of the conjugated diene polymer containing a nitrogen atom relative to the total amount of the mixture of conjugated diene polymers.

[0177] Except where specifically mentioned in this specification, or where clearly distinguished, such as by being listed in parallel as “conjugated diene polymer or modified conjugated diene polymer,” “conjugated diene polymer” includes unmodified conjugated diene polymer and modified conjugated diene polymer.

[0178] In addition, in cases where they are listed in parallel as "conjugated diene polymer or modified conjugated diene polymer," "conjugated diene polymer" refers to an unmodified conjugated diene polymer.

[0179] For example, in a conjugated diene polymer comprising a modified conjugated diene polymer obtained by reacting a modifying agent containing a nitrogen atom at the terminal end, the mass ratio of the modified conjugated diene polymer having a nitrogen atom-containing functional group attributable to the nitrogen atom-containing modifying agent to the total amount of the conjugated diene polymer is the modification rate.

[0180] With respect to improving processability when making a vulcanized product, the modification rate of the conjugated diene polymer of the present embodiment is preferably less than 40 mass%, more preferably 30 mass% or less, even more preferably 20 mass% or less, even more preferably 10 mass% or less, even more preferably 5 mass% or less, and most preferably 0 mass% with respect to the total amount of the conjugated diene polymer. If the modification rate is 40 mass% or more, there is a tendency for processability to deteriorate, such as the increase in the viscosity of the composition due to the reaction with silica particles during the mixing process, making it difficult to mix, or the occurrence of surface roughness or sheet breakage when forming it into a sheet after mixing. By having a modification rate of less than 40 mass%, the processability when making a vulcanized product is excellent, and in particular, when making a vulcanized product containing inorganic fillers such as silica, the decrease in hardness caused by excessive dispersion of silica can be suppressed.

[0181] In the conjugated diene polymer of the present embodiment, the modification rate can be measured by chromatography capable of separating the modified component containing functional groups from the non-modified component. As a method using this chromatography, a method of quantifying by using a column for gel permeation chromatography packed with a polar material such as silica that adsorbs specific functional groups, and using an internal standard of the non-adsorbed component for comparison (column adsorption GPC method) can be cited.

[0182] More specifically, the denaturation rate can be obtained by calculating the amount of adsorption to the silica column from the difference between the chromatogram measured by a polystyrene-based gel column for a sample solution containing the sample and a low molecular weight internal standard polystyrene, and the chromatogram measured by a silica-based column for the sample solution. Specifically, the denaturation rate can be measured by the method described in the examples below.

[0183] In the conjugated diene polymer of the present embodiment, the modification rate can be controlled to the above-described numerical range by adjusting the ratio of components A and B, the amount of coupling modifier added during the polymerization of components A and B, and the reaction method between the conjugated diene compound and the modifier.

[0184] For example, components A and B can be obtained by combining a method of polymerizing using an organolithium compound having at least one nitrogen atom in its molecule as described below as a polymerization initiator, a method of copolymerizing a monomer having at least one nitrogen atom in its molecule, and a method of using a modifying agent of the structural formula described below, and then adjusting their ratios.

[0185] (Nitrogen content)

[0186] The conjugated diene polymer of the present embodiment has a nitrogen content that is preferably 100 ppm or less, more preferably 50 ppm or less, even more preferably 30 ppm or less, even more preferably 20 ppm or less, even more preferably 10 ppm or less, and most preferably 0 ppm.

[0187] If the nitrogen content is 100 ppm or less, the viscosity of the composition does not become excessively high even if a reaction with silica particles proceeds during the mixing process, so mixing is easy, the sheet texture after mixing is good, and processability tends to be excellent. In addition, especially when using a vulcanized material containing inorganic fillers such as silica, the decrease in hardness caused by excessive dispersion of silica can be suppressed.

[0188] The nitrogen content can be controlled to the above numerical range by appropriately adjusting the ratio of components A and B, the ratio of nitrogen included in the modifying agent during the polymerization of components A and B, the amount of nitrogen-containing modifying agent added, and the amount of modifying agent bound to the polymerization end.

[0189] (Silicon content)

[0190] The conjugated diene polymer of the present embodiment preferably has a silicon content of 1 ppm or more and 200 ppm or less.

[0191] In a rubber composition in which a conjugated diene polymer of the present embodiment is mixed with a reinforcing material by having a silicon content of 1 ppm or more, the interaction between the conjugated diene polymer and the reinforcing material is strengthened, and when vulcanized, the fracture strength and wear resistance tend to be excellent.

[0192] The silicon content of the conjugated diene polymer of the present embodiment is more preferably 2 ppm or more, more preferably 3 ppm or more, more preferably 4 ppm or more, and most preferably 5 ppm or more.

[0193] By having a silicon content of 200 ppm or less, discoloration caused by deterioration over time of the conjugated diene polymer can be suppressed. The silicon content of the conjugated diene polymer of the present embodiment is more preferably 150 ppm or less, more preferably 100 ppm or less, more preferably 50 ppm or less, and most preferably 30 ppm or less.

[0194] The silicon content can be controlled to the above numerical range by adjusting the ratio of components A and B, or by carrying out a coupling reaction using a silicon-containing coupling agent in the polymerization of components A and B, and adjusting the amount of added silicon-containing coupling agent.

[0195] (Microstructure of conjugated diene polymers)

[0196] Since the microstructure of a conjugated diene polymer (the ratio of the amount of conjugated vinyl aromatic monomer units, the amount of conjugated conjugated diene monomer units, and the amount of vinyl bonds in the conjugated conjugated diene monomer units) affects the glass transition temperature of the conjugated diene polymer, there exists a desirable range for the amount of conjugated vinyl aromatic monomer units or the amount of vinyl bonds from the perspective of controlling the glass transition temperature. Among the microstructures of the conjugated diene polymer, the amount of conjugated vinyl aromatic monomer units is not particularly limited, but it is preferably 0 mass% or more and 30 mass% or less with respect to the entire conjugated diene polymer, more preferably 1 mass% or more and 28 mass% or less, and even more preferably 5 mass% or more and 25 mass% or less. When the amount of conjugated vinyl aromatic monomer units is within the above range, the vulcanizate of the conjugated diene polymer tends to have even better fracture strength, wear resistance, and low hysteresis loss. In addition, as the amount of conjugated vinyl aromatic monomer units increases, the Tg of the conjugated diene polymer tends to increase, and as it decreases, the Tg tends to decrease.

[0197] In this specification, "unit amount of combined vinyl aromatic monomer" refers to the content of the portion derived from the aromatic vinyl compound used as a monomer.

[0198] In the microstructure of the conjugated diene polymer, the unit amount of the bound conjugated diene monomer is not particularly limited, but it is preferably 70 mass% or more and 100 mass% or less with respect to the entire conjugated diene polymer, more preferably 72 mass% or more and 99 mass% or less, and even more preferably 75 mass% or more and 95 mass% or less. When the unit amount of the bound conjugated diene monomer is within the above range, the vulcanizate of the conjugated diene polymer tends to have even better fracture strength, wear resistance, and low hysteresis loss. Furthermore, in this specification, "unit amount of the bound conjugated diene monomer" refers to the content of the portion derived from the conjugated diene compound used as a monomer.

[0199] Among the microstructures of conjugated diene polymers, the vinyl bond amount in the conjugated diene monomer units (hereinafter simply referred to as "vinyl bond amount") is not particularly limited, but it is preferably 10 mol% or more and 60 mol% or less with respect to the total conjugated diene monomer units, more preferably 11 mol% or more and 40 mol% or less, even more preferably 12 mol% or more and 35 mol% or less, even more preferably 13 mol% or more and 30 mol% or less, even more preferably 14 mol% or more and 29 mol% or less, and particularly preferably 15 mol% or more and 28 mol% or less. When the vinyl bond amount is within the above range, the conjugated diene polymer tends to have even better fracture strength and wear resistance because the linearity of the structure of the conjugated diene portion is increased and the entanglement between polymer chains becomes stronger. In addition, when the vinyl bond amount is within the above range, the vulcanized product tends to have even better low hysteresis loss properties.

[0200] In addition, as the vinyl bond amount increases, Tg increases, and as it decreases, Tg decreases. In this specification, "vinyl bond amount in a conjugated diene monomer unit" refers to the ratio of the portion having vinyl bonds among the portion derived from the conjugated diene compound used as a monomer (hereinafter referred to as "conjugated diene monomer unit").

[0201] (Branch map(Bn))

[0202] In this specification, the degree of branching (Bn) is calculated using a shrinkage factor (g') from the formula g' = 6Bn / {(Bn+1)(Bn+2)}. Here, the shrinkage factor (g') is the following value.

[0203] Generally, branched polymers tend to have smaller molecular sizes compared to straight-chain polymers having the same absolute molecular weight. Here, "molecular size" refers to the volume substantially occupied by the molecule. The shrinkage factor (g') represents the relative size of the target polymer molecule and is an indicator of the ratio of the size of the target polymer molecule to the size of a straight-chain polymer molecule having the same absolute molecular weight. In other words, if the degree of branching of the polymer is high, its size becomes relatively smaller, and thus the shrinkage factor (g') tends to decrease.

[0204] Here, since it is known that the size of the polymer molecule and the ratio of intrinsic viscosity are correlated, in this embodiment, the shrinkage factor (g') is defined as the ratio of intrinsic viscosities. That is, the shrinkage factor (g') is defined as the ratio ([η] / [η0]) of the intrinsic viscosity [η] of the target polymer to the intrinsic viscosity [η0] of a straight-chain polymer having the same absolute molecular weight as the target polymer.

[0205] In addition, the intrinsic viscosity [η0] of the linear polymer is [η0]=10 -3.534 M 0.712 It is known that the relationship follows the equation. In the equation, M is the absolute molecular weight. Therefore, the absolute molecular weight and intrinsic viscosity of the target polymer can be measured by the GPC-light scattering method equipped with a viscosity detector, thereby obtaining the shrinkage factor (g') and branching degree (Bn). The calculated branching degree (Bn) accurately represents the number of polymer chains that are directly or indirectly bonded to each other with respect to the longest polymer main chain.

[0206] Here, "absolute molecular weight" refers to the molecular weight measured by the light scattering method. As described above, generally, branched polymers tend to have smaller molecular sizes when compared to straight-chain polymers having the same absolute molecular weight. Therefore, in the GPC measurement method, which determines molecular weight by sieving polymer molecules by size and comparing them relative to standard polystyrene samples, the molecular weight of polymers with branched structures tends to be underestimated. On the other hand, the light scattering method measures molecular weight by directly observing the molecules. Therefore, the light scattering method can accurately measure molecular weight without being affected by the polymer structure or interactions with column packing materials. Furthermore, the absolute molecular weight can be measured by the method described in the examples below.

[0207] In addition, "intrinsic viscosity" refers to the viscosity [η], which is ideally obtained by the following equation (I).

[0208] In addition, in Equation (I), η1 represents the viscosity when the target polymer is dissolved in a solvent at a concentration c, and η2 represents the viscosity of the solvent.

[0209] In this specification, the intrinsic viscosity used is the value measured by the method described in the examples below.

[0210]

[0211] The above shrinkage factor represents the rate of reduction in molecular size and does not accurately represent the branched structure of the polymer.

[0212] Therefore, the branching degree (Bn) of the modified conjugated diene polymer is calculated using the value of the shrinkage factor (g') at each absolute molecular weight of the modified conjugated diene polymer. The calculated "branching degree (Bn)" accurately represents the number of polymers directly or indirectly bonded to each other with respect to the longest main chain structure.

[0213] The calculated degree of branching (Bn) serves as an indicator representing the branching structure of the modified conjugated diene polymer. For example, in the case of a typical tetrabranched star polymer (where four polymer chains are connected in the center), two female polymer chains are connected to the longest highly branched main chain structure, so the degree of branching (Bn) is evaluated as 2.

[0214] In the case of a typical 8-branched star polymer, six females of the polymer chain are bonded to the longest high-branched main chain structure, so the degree of branching (Bn) is evaluated as 6.

[0215] Here, "branching" refers to the formation of a polymer by directly or indirectly bonding to a single polymer. Additionally, "degree of branching (Bn)" is the number of polymers directly or indirectly bonded to each other with respect to the longest main chain structure. That is, not only the side chains bonded to the longest polymer chain, but also the number of branches of the side chains if the side chains are further branched are taken into account. Therefore, if one polymer chain is bonded as a side chain to the longest polymer chain, and another polymer chain is bonded to that side chain, the degree of branching is 2.

[0216] (Branching of the polymer region (Bn))

[0217] In the conjugated diene polymer of the present embodiment, when the absolute molecular weight at the first inflection point is Mw1 and the absolute molecular weight at the peak end point is Mw2 in the region on the high molecular weight side rather than the peak top of the absolute molecular weight curve measured by the GPC-light scattering method equipped with a viscosity detector, it is preferable that the degree of branching (Bn) at the absolute molecular weight of (Mw1+Mw2) / 2 is 4 or higher, more preferably 5 or higher, and even more preferably 6 or higher. If the degree of branching (Bn) at the absolute molecular weight of (Mw1+Mw2) / 2 is 4 or higher, the bale moldability is good, the processability when making a vulcanized product is excellent, and since the torque of the mixer is easily applied when kneading with the filler, there is a tendency to easily disperse the filler in a short time.

[0218] Here, the "peak endpoint" refers to the point where the absolute molecular weight is greatest, determined by the GPC-light scattering method equipped with a viscosity detector.

[0219] Generally, as the absolute molecular weight increases, processability tends to deteriorate; therefore, when the absolute molecular weight is increased in a linear polymer structure, the viscosity increases significantly when it is vulcanized, and processability deteriorates significantly.

[0220] Therefore, even if a number of functional groups are introduced into the polymer to improve affinity and / or reactivity with silica blended as a filler, the silica cannot be sufficiently dispersed into the polymer during the mixing process. As a result, the function of the introduced functional groups is not exhibited, and the effect of improved low hysteresis loss and wet skid resistance due to the introduction of functional groups, which should have been originally expected, is not exhibited.

[0221] Meanwhile, the conjugated diene polymer of the present embodiment is specified such that the degree of branching (Bn) in the absolute molecular weight (Mw1+Mw2) / 2 is 4 or higher, thereby suppressing the increase in viscosity when vulcanized that accompanies an increase in absolute molecular weight. In addition, since the torque of the mixer is easily applied when kneading with fillers such as silica, it is possible to sufficiently mix with silica during the kneading process and disperse the silica. As a result, for example, in the conjugated diene polymer, it is possible to improve wear resistance and fracture strength by setting the molecular weight high, and it is also possible to disperse silica through sufficient kneading even with a low modification rate. This makes it possible to have sufficient low hysteresis loss and wet skid resistance for practical use.

[0222] The absolute molecular weight of a conjugated diene polymer can be measured by the method described in the examples below.

[0223] In addition, the upper limit of the branching degree (Bn) is not particularly limited and may be greater than the detection limit value, but preferably 84 or less, more preferably 80 or less, even more preferably 60 or less, particularly preferably 40 or less, and even more preferably 20 or less.

[0224] The conjugated diene polymer of the present embodiment tends to have excellent wear resistance when vulcanized with a branching degree (Bn) of 84 or less.

[0225] The degree of branching of a conjugated diene polymer can be controlled by the number of functional groups of the branching agent, the amount of the branching agent added, the timing of the addition of the branching agent, and the number of functional groups of the coupling agent or the nitrogen atom-containing modifier, and the amount of the coupling agent or the nitrogen atom-containing modifier added. More specifically, this is described in the method for manufacturing a conjugated diene polymer described below.

[0226] Generally, the wear resistance and fracture strength of polymers tend to be superior as their absolute molecular weight increases. However, when the absolute molecular weight of a polymer with low branching is increased, polymer particles become prone to peeling off from the surface of the bale, leading to a deterioration in bale formability. Furthermore, viscosity increases significantly during vulcanization, which tends to drastically worsen processability during the process. Consequently, in polymers with low branching, silica cannot be sufficiently dispersed within the polymer during the mixing process. As a result, constraints on processability lead to limitations in the design freedom of the molecular weight.

[0227] (Shrinkage factor (g') at peak top molecular weight (Mp))

[0228] The conjugated diene polymer of the present embodiment preferably has a shrinkage factor (g') of 0.90 or higher at the peak top molecular weight (Mp) obtained by the GPC-light scattering measurement method equipped with a viscosity detector, more preferably 0.91 or higher, and even more preferably 0.92 or higher. If the shrinkage factor (g') at the peak top molecular weight (Mp) is 0.90 or higher, the number of free ends is reduced, thereby suppressing energy loss and tending to have excellent fuel efficiency saving performance.

[0229] The upper limit of the contraction factor (g') at the peak top molecular weight (Mp) is not specifically limited, but may be, for example, 2.00, 1.50, or 1.00.

[0230] A numerical range may be defined by appropriately combining the lower and upper limits of the shrinkage factor (g') at the peak top molecular weight (Mp). The range of the shrinkage factor (g') at the peak top molecular weight (Mp) may be, for example, 0.90 to 2.00, 0.91 to 1.50, or 0.92 to 1.00.

[0231] (Shrinkage factor (g') in number-average molecular weight (Mn))

[0232] The conjugated diene polymer of the present embodiment preferably has a shrinkage factor (g') of the number average molecular weight (Mn) obtained by the GPC-light scattering measurement method equipped with a viscosity detector of 0.90 or higher, more preferably 0.91 or higher, and even more preferably 0.92 or higher. If the shrinkage factor (g') of the number average molecular weight (Mn) is 0.90 or higher, the number of free ends is reduced, thereby suppressing energy loss and tending to have excellent fuel efficiency saving performance.

[0233] The upper limit of the shrinkage factor (g') in the number average molecular weight (Mn) is not specifically limited, but may be, for example, 2.00, 1.50, or 1.00.

[0234] A numerical range may be defined by appropriately combining the lower and upper limits of the shrinkage factor (g') in the number average molecular weight (Mn). The range of the shrinkage factor (g') in the number average molecular weight (Mn) may be, for example, 0.90 to 2.00, 0.91 to 1.50, or 0.92 to 1.00.

[0235] From the perspective of obtaining a superior effect, the shrinkage factor (g') at the peak top molecular weight (Mp) and the shrinkage factor (g') at the number average molecular weight (Mn) are both preferably 0.90 or higher, more preferably 0.91 or higher, and even more preferably 0.92 or higher.

[0236] The shrinkage factor (g') in the peak top molecular weight (Mp) and the shrinkage factor (g') in the number average molecular weight (Mn) may both be 0.90 to 2.00, 0.91 to 1.50, or 0.92 to 1.00.

[0237] (Moony viscosity of conjugated diene polymers)

[0238] Mooney viscosity is an indicator representing the comprehensive characteristics of a conjugated diene polymer, encompassing information on molecular weight, molecular weight distribution, branching degree, and softener content. Furthermore, since the measurement method for Mooney viscosity is specified in ISO 289, the error in measurement values ​​due to machine variations is small, making it highly effective for controlling the performance of conjugated diene polymers.

[0239] The Mooney viscosity (hereinafter also simply referred to as "Mooney viscosity" or "ML") of the conjugated diene polymer of the present embodiment, measured at 100°C, is preferably 20 or higher, and is more preferably 30 or higher and even more preferably 40 or higher from the perspective of steering stability, fracture strength, and wear resistance when the crosslinking rubber composition containing the conjugated diene polymer of the present embodiment is used in a tire.

[0240] Meanwhile, the upper limit is preferably 170 or less, and from the perspective of moldability, productivity of a rubber composition containing a molded body of various shapes such as a sheet or block or a conjugated diene polymer of the present embodiment, and processability of a rubber composition mixed with fillers, etc., 160 or less is more preferable, 150 or less is even more preferable, and 145 or less is particularly preferable.

[0241] The Mooney viscosity of a conjugated diene polymer is determined by using a sample of the conjugated diene polymer condensed into a plate using a pressure press, setting it in a measuring device, preheating the sample at 100°C for 1 minute, rotating the rotor at 2 rpm, measuring the torque after 4 minutes, and using the measured value as the Mooney viscosity (ML). (1+4) ...does as ).

[0242] The Mooney viscosity of the conjugated diene polymer of the present embodiment can be controlled to the above numerical range by adjusting the type, timing, and amount of the branching agent and coupling modifier, the molecular weight, molecular weight distribution, and degree of branching of the conjugated diene polymer, and by adjusting the ratio of A and B for each of components A and B.

[0243] (Moony relaxation rate of conjugated diene polymers)

[0244] The Mooney relaxation rate (hereinafter also referred to simply as "Mooney relaxation rate" or "MSR") of the conjugated diene polymer of the present embodiment, measured at 100°C, is preferably 0.9 or less, and from the perspective of processability of a rubber composition in which a filler or the like is blended with the conjugated diene polymer, it is more preferable to have a rate of 0.8 or less, and even more preferable to have a rate of 0.75 or less. Meanwhile, the Mooney relaxation rate is preferably 0.25 or more, and from the perspective of steering stability and fracture strength when the conjugated diene polymer of the present embodiment is used as a tire material, it is more preferable to have a rate of 0.28 or more, and even more preferable to have a rate of 0.30 or more.

[0245] Similar to Mooney viscosity, the Mooney relaxation rate is influenced by the molecular weight, molecular weight distribution, degree of branching, and softening agent content of the conjugated diene polymer, serving as an indicator representing the overall characteristics of the conjugated diene polymer.

[0246] MSR can be measured as follows using a Mooney viscometer.

[0247] The Mooney relaxation rate is determined by first preheating the sample at 100°C for 1 minute, then rotating the rotor at 2 rpm, and finally using the Mooney viscosity (ML) from the torque after 4 minutes. (1+4) After measuring, immediately stop the rotation of the rotor, record the torque in Mooney units at intervals of 0.1 seconds for 1.6 to 5 seconds after stopping, calculate the slope of the straight line when plotting torque and time (seconds) on a logarithmic scale, and set the absolute value as the Mooney relaxation rate (MSR).

[0248] The Mooney relaxation rate of the conjugated diene polymer of the present embodiment can be controlled to the above numerical range by adjusting the type, timing, and amount of the branching agent and coupling modifier, the molecular weight, molecular weight distribution, and degree of branching of the conjugated diene polymer for each of components A and B, and by adjusting the ratio of A and B.

[0249] (Plastic body)

[0250] The molded article of the present embodiment is a molded article comprising the conjugated diene polymer of the present embodiment described above. From the perspective of handling ease, it is preferable that the molded article be in the form of a sheet or a block.

[0251] The size or thickness of the sheet-like or block-like molded body is not particularly limited, but examples include a sheet-like molded body with a thickness of about 1 cm, and a block-like molded body with a rectangular or cubic shape of 1,000 cm³.

[0252] The molded body of the present embodiment is more preferably a block-shaped molded body, and as for the shape of the block, it is preferably a roughly rectangular prism, and it is even more preferably a block-shaped (bale) molded body of 1,000 cm³ or more. In addition, it is even more preferable to be a rectangular prism-shaped bale weighing 17.5 kg to 35 kg.

[0253] As a molding method, it is preferable to produce a crumb with a specific surface area of ​​0.7 m² / g to 3.2 m² / g and to compression mold the crumb. From the perspective of moldability, it is preferable to further perform a process of sieving the crumb before molding.

[0254] When compression molding crumbs, the crumbs adhere closely to each other, so the specific surface area of ​​the molded body becomes smaller than the specific surface area of ​​the crumbs. The adhesion of the crumbs during compression molding can be adjusted by the molecular weight, composition, and structure of the conjugated diene polymer, the composition of the softener component, and the temperature and pressure during compression. For example, if one wishes to increase the adhesion of the crumbs to lower the specific surface area of ​​the bale, conditions such as lowering the molecular weight of the conjugated diene polymer, increasing the amount of the softener component, or increasing the temperature and pressure during compression are desirable.

[0255] The specific surface area of ​​the molded body in this embodiment is preferably 0.005 to 0.05 m² / g, and more preferably 0.01 to 0.04 m² / g for film packaging properties. It is desirable that the specific surface area of ​​the molded body be 0.005 m² / g or more to suppress the expansion of the bale, and that the specific surface area of ​​the molded body be 0.05 m² / g or less to reduce the peeling of crumbs from the molded body.

[0256] The specific surface area of ​​the molded body can be determined by the BET method.

[0257] Typically, since the specific surface area of ​​a large-sized molded body varies depending on the location, it is desirable to take a sample near the center of the molded body.

[0258] Before molding, it is desirable to sieve the crumbs by particle size and then mix them in an appropriate ratio.

[0259] If the specific surface area of ​​a molded body formed using the crumb after solvent removal as is exceeds the upper limit of the above range, it is desirable to increase the composition of large-sized crumbs and decrease the composition of small-sized crumbs among the sieve-sorted crumbs; if it does not reach the lower limit, it is desirable to decrease the composition of large-sized crumbs and increase the composition of small-sized crumbs.

[0260] The molding compression pressure of the molded body is preferably 3 MPa to 30 MPa, more preferably 10 MPa to 20 MPa. When the compression pressure during molding is 30 MPa or less, the device can be designed compactly, resulting in good installation efficiency, and when the compression pressure during molding is 3 MPa or more, the moldability is good. When the moldability is good, the surface of the molded body is smooth, there is no peeling of the polymer after the molding process, and there is a tendency for expansion after molding to be suppressed.

[0261] The temperature of the conjugated diene polymer or the rubber composition containing said conjugated diene polymer during molding is preferably 30 to 120°C, and more preferably 50 to 100°C for the purpose of reducing residual solvent and suppressing thermal degradation.

[0262] When the temperature during molding is 30°C or higher, the moldability is good, and on the other hand, when the temperature is 120°C or lower, gel formation due to thermal degradation of the rubber composition is suppressed, so it is desirable.

[0263] The higher the temperature and pressure during molding, the smaller the specific surface area of ​​the bale.

[0264] The holding pressure time during molding is preferably 3 to 30 seconds, and more preferably 5 to 20 seconds. When the holding pressure time during compression is 30 seconds or less, production efficiency is good, and when it is 5 seconds or more, moldability is good.

[0265] It is desirable to wrap them in a resin film (packaging sheet) to avoid close contact between the molded bodies.

[0266] For example, the resin type of the film can be polyethylene, ethylene copolymer resin, polystyrene, high-impact polystyrene, or PET.

[0267] From the perspective of handling the molded body during transportation and preventing condensation from forming in the gap between the packaging sheet and the bale, it is desirable for the packaging sheet to have good adhesion.

[0268] The molded body of the present embodiment is used for, for example, to be stored in a transport container. If the expansion rate of the molded body after one day has elapsed since molding is less than 5%, it is desirable for the storage ability in the container to be good.

[0269] The sheet- or block-shaped molded article using the conjugated diene polymer of the present embodiment may have a softening agent component described later added thereto, but in the molded article of the present embodiment, from the perspective of improving the degree of freedom of compounding when manufacturing the rubber composition described later, it is preferable that the softening agent component be 2 parts by mass or less per 100 parts by mass of the conjugated diene polymer, more preferable that it be 1.5 parts by mass or less, even more preferable that it be 1 part by mass or less, even more preferable that it be less than 1 part by mass, and most preferable that it be in a state where no softening agent component is added.

[0270] In addition, although the softening agent component used in the manufacture of the rubber composition described below is sometimes labeled as a "rubber softener," this is merely a literal distinction made from the softening agent component used in molded articles of conjugated diene polymers, and does not distinguish the material itself.

[0271] (Amount of organic acid contained in the molded body)

[0272] The molded article of the present embodiment may contain an organic acid in addition to the conjugated diene polymer of the present embodiment described above. As for the organic acid, it is not particularly limited as long as it is a compound having an acidic group and a hydrocarbon group. Examples of acidic groups include carboxyl groups, sulfonate groups, hydroxyl groups, and groups derived from phosphate esters. It is preferable that the organic acid is a compound that does not have a group derived from phosphate esters and has a carboxyl group. As the organic acid, organic carboxylic acids such as aliphatic carboxylic acids and aliphatic hydroxycarboxylic acid compounds may be suitably used.

[0273] As an aliphatic carboxylic acid, a compound having a hydrocarbon group having 2 to 30 carbon atoms and a carboxyl group may be used. Examples of aliphatic carboxylic acids include saturated aliphatic carboxylic acids such as acetic acid, octanoic acid, decanoic acid, undecylic acid, lauric acid, tridecytic acid, myristic acid, pentadecylic acid, palmitic acid, heptadecanic acid, stearic acid, nonadecylic acid, and arachidic acid; and unsaturated aliphatic carboxylic acids such as palmitoleic acid, oleic acid, ricinoleic acid, linoleic acid, linolenic acid, myristoleic acid, arachidonic acid, icosapentaenoic acid, and docosahexaenoic acid. Due to ease of availability, stearic acid is preferably used.

[0274] As an aliphatic hydroxycarboxylic acid compound, an aliphatic compound having a hydroxyl group and a carboxyl group may be used. It is preferable that the aliphatic hydroxycarboxylic acid compound has a straight-chain hydrocarbon group, and said hydrocarbon group may have an unsaturated bond. If it has an unsaturated bond, a trans form is preferred. The number of carbon atoms of the aliphatic hydroxycarboxylic acid compound is preferably 2 to 40, and more preferably 8 to 30.

[0275] Examples of aliphatic hydroxycarboxylic acid compounds include hydroxycaprylic acid, hydroxylauric acid, hydroxypalmitic acid, hydroxystearic acid, dihydroxystearic acid, and hydroxyelaidic acid. As an aliphatic hydroxycarboxylic acid compound, which can further inhibit cold flow, it is preferably 12-hydroxystearic acid or 2-hydroxycaprylic acid, and more preferably 12-hydroxystearic acid.

[0276] In a process for obtaining a molded article comprising a conjugated diene polymer of the present embodiment, the process of obtaining a crumb of the conjugated diene polymer by removing a solvent from a conjugated diene polymer solution of the conjugated diene polymer of the present embodiment is provided.

[0277] Methods for removing solvent from a conjugated diene polymer solution are not particularly limited, but include known desolvation methods such as steam stripping and drying operations such as dehydration extruders, drying extruders, and heat treatment using conveyors.

[0278] In the heat treatment process using the above conveyor, crumbs tend to adhere to the conveyor, but the presence of an organic acid tends to suppress the adhesion of crumbs to the conveyor. The content of the organic acid is preferably 0.01 parts by mass or more, more preferably 0.02 parts by mass or more, even more preferably 0.03 parts by mass or more, and particularly preferably 0.04 parts by mass or more, per 100 parts by mass of the conjugated diene polymer. On the other hand, if the content of the organic acid is high, the thermal stability of the crumbs tends to decrease, increasing the risk of ignition during the drying process. From the perspective of production safety, the content is preferably 2.0 parts by mass or less, more preferably 1.5 parts by mass or less, even more preferably 1.0 parts by mass or less, and particularly preferably 0.5 parts by mass or less, per 100 parts by mass of the conjugated diene polymer.

[0279] Any range may be determined by appropriately combining the upper and lower limits of the organic acid content described above. For example, with respect to 100 parts by mass of a conjugated diene polymer, the organic acid content may be 0.01 to 2.0 parts by mass, 0.02 to 1.5 parts by mass, 0.03 to 1.0 parts by mass, or 0.04 to 0.5 parts by mass.

[0280] (Method for manufacturing conjugated diene polymers)

[0281] A conjugated diene polymer (A) and a conjugated diene polymer (B) are each obtained by serial polymerization using one or more reactors, and after mixing the respective polymer solutions, a conjugated diene polymer of the present embodiment is obtained by solvent removal. The molecular weight distribution curve obtained by gel permeation chromatography (GPC) measurement is unimodal, and the conjugated diene polymer has a shoulder in the region from the peak top of the molecular weight distribution curve to the peak end point on the high molecular weight side, and the manufacturing method is not limited.

[0282] (Conjugated diene polymer (A) and conjugated diene polymer (B))

[0283] The conjugated diene polymer (A) has a weight-average molecular weight (Mw) of 50×10 as measured by gel permeation chromatography (GPC). 4 More than 300×10 4 The conjugated diene polymer (B) has an Mw of 10×10 as measured by GPC. 4 50×10 or more 4 It is as follows.

[0284] The weight-average molecular weight (Mw) of the conjugated diene polymer (A) is 50×10 4 More than 300×10 4 Less than or equal to, preferably 60×10 4 More than 200×10 4 Less than, and more preferably 700×10 4 150×10 or more 4 The following applies. In terms of wear resistance when used as a vulcanized material, 50×10 4 That is all, and in terms of the balance between processability when using a vulcanized material and wear resistance when using a vulcanized material, 300×10 4 It shall be considered as less than or equal to 150×10 4 It is desirable that it be less than or equal to this.

[0285] The weight-average molecular weight (Mw) of the conjugated diene polymer (B) is 10×10 4 50×10 or more 4Less than or equal to, preferably 15×10 4 40×10 or more 4 Less than or equal to, and more preferably 20×10 4 30×10 or more 4 The following applies. In terms of wear resistance when using a vulcanized material, 10×10 4 That is all, and in terms of the balance between processability when using a vulcanized material and wear resistance when using a vulcanized material, 50×10 4 Less than or equal to, and 30×10 4 It is desirable that it be less than or equal to this.

[0286] ΔMw, the difference in weight-average molecular weight (Mw) between the conjugated diene polymer (A) and the conjugated diene polymer (B), is 20×10 4 It is desirable that it be more than 30×10, and more preferably 30×10 4 That is all, and more preferably 40×10 4 That is all, and more preferably 50×10 4 That is all. The upper limit of ΔMw is not specifically limited, but for example, 200×10 4 , 150×10 4 , 100×10 4 , or 80×10 4 You can do it like this.

[0287] In this range, there is a tendency for an excellent balance between the processability when using vulcanized material and the wear resistance when using vulcanized material.

[0288] Wear resistance tends to be superior in those with larger molecular weights, while machinability tends to be superior in those with smaller molecular weights.

[0289] The one with a larger difference in weight-average molecular weight between the conjugated diene polymer (A) and the conjugated diene polymer (B) means that if it is the conjugated diene polymer (A), it becomes a conjugated diene polymer specialized for wear resistance, and if it is the conjugated diene polymer (B), it becomes a modified conjugated diene polymer specialized for processability.

[0290] Therefore, when the two are mixed, there is also a strong tendency for mutual complementarity.

[0291] The weight average molecular weight (Mw) of conjugated diene polymers (A) and (B) can be controlled by adjusting the polymerization temperature, the amount of monomer added, and the amount of polymerization initiator added in each polymerization process.

[0292] Increasing the polymerization temperature during the polymerization process accelerates the reaction rate, which tends to yield polymers with a high weight-average molecular weight. However, if the polymerization temperature is raised excessively, heat-induced deactivation of the polymer ends becomes more likely, making it difficult to increase the weight-average molecular weight of conjugated diene polymers.

[0293] When the amount of monomer added in the polymerization process is increased, the amount of monomer polymerized per molecule of polymerization initiator increases, so the weight-average molecular weight tends to increase.

[0294] When the amount of polymerization initiator added in the polymerization process is increased, the amount of monomer polymerized per molecule of polymerization initiator decreases, so the weight-average molecular weight tends to decrease.

[0295] From this, the difference in weight average molecular weight (ΔMw) between the conjugated diene polymer (A) and (B) can be controlled to the above numerical range by appropriately adjusting the conditions in the polymerization process of the conjugated diene polymer (A) and / or the modified conjugated diene polymer (B).

[0296] (Method for preparing conjugated diene polymer (A) and conjugated diene polymer (B))

[0297] The method for manufacturing conjugated diene polymers (A) and (B) is described in detail below.

[0298] By using the method for manufacturing a conjugated diene polymer described in detail below, the conjugated diene polymer described above can be obtained reliably and easily, but the conjugated diene polymer of the present embodiment is not limited to being manufactured by the manufacturing method below.

[0299] Polymerization Process

[0300] In the polymerization process of conjugated diene polymers (A) and (B), an organic lithium compound is used as a polymerization initiator, and at least a conjugated diene compound is polymerized to obtain a conjugated diene polymer.

[0301] In the polymerization process, at least a conjugated diene compound is polymerized, but if necessary, a copolymerization of the conjugated diene compound and an aromatic vinyl compound, a process of obtaining a conjugated diene-based polymer having a branched structure by adding a branching agent (hereinafter, all may be described as the polymerization branching process), and a process of adding a coupling modifier are included.

[0302] As for the conjugated diene compound, it is not particularly limited as long as it is a polymerizable monomer, but a conjugated diene compound having 4 to 12 carbon atoms per molecule is preferred, and more preferably a conjugated diene compound having 4 to 8 carbon atoms.

[0303] Examples of such conjugated diene compounds include, but are not limited to, 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 3-methyl-1,3-pentadiene, 1,3-hexadiene, and 1,3-heptadiene.

[0304] Among these, 1,3-butadiene and isoprene are preferred from the perspective of ease of industrial availability. These may be used individually or in combination of two or more.

[0305] As for the aromatic vinyl compound, it is not particularly limited as long as it is a monomer copolymerizable with a conjugated diene compound, but a monovinyl aromatic compound is preferred.

[0306] Examples of monovinyl aromatic compounds include, but are not limited to, styrene, p-methylstyrene, α-methylstyrene, vinylethylbenzene, vinylxylene, vinylnaphthalene, and diphenylethylene. Among these, styrene is preferred from the perspective of ease of industrial availability. These may be used as a single type or in combination of two or more types.

[0307] The polymerization reaction of conjugated diene compounds and aromatic vinyl compounds is preferably a polymerization by a growth reaction via living anionic polymerization, thereby enabling the production of conjugated diene polymers having active ends. As a result, when a branching agent is added, the conjugated diene polymer and the branching agent react efficiently. Furthermore, even when the coupling process described later is used, there is a tendency to perform a highly efficient reaction.

[0308] As polymerization reaction modes, examples include batch (hereinafter also referred to as “batch type”) and continuous polymerization reaction modes, although not limited to the following.

[0309] In the continuous type, one or more connected reactors may be used. As a reactor for the continuous type, for example, a tubular or tubular type equipped with a stirrer is used. In the continuous type, preferably, a monomer, an inert solvent described later, and a polymerization initiator described later are fed into the reactor continuously, a polymer solution containing a polymer is obtained within the reactor, and the polymer solution is continuously discharged.

[0310] As a batch reactor, for example, a molded reactor equipped with a stirrer is used. In the batch process, preferably, a monomer, an inert solvent described later, and a polymerization initiator described later are fed, and if necessary, the monomer is added continuously or intermittently during polymerization to obtain a polymer solution containing the polymer within the reactor, and the polymer solution is discharged after the polymerization is completed.

[0311] In a method for manufacturing conjugated diene polymers (A) and (B), it is preferable to carry out the polymerization reaction by a continuous polymerization reaction mode in which the polymer can be continuously discharged and provided to the next reaction in a short time, from the perspective of obtaining a conjugated diene polymer having active ends in a high proportion.

[0312] The conjugated diene polymer obtained from the polymerization process may be a random copolymer or a block copolymer.

[0313] Examples of random copolymers include, but are not limited to the following, random copolymers containing two or more conjugated diene compounds such as butadiene-isoprene random copolymer, butadiene-styrene random copolymer, isoprene-styrene random copolymer, and random copolymer containing a conjugated diene compound and an aromatic vinyl compound.

[0314] The compositional distribution of each monomer in the copolymer chain is not particularly limited, and examples include a completely random copolymer with a composition close to statistically random, and a tapered random copolymer with a composition distributed in a tapered shape. The composition of the conjugated diene bonding pattern, such as 1,4-links or 1,2-links, may be uniform or distributed.

[0315] Examples of block copolymers include, but are not limited to, a type 2 block copolymer (diblock) containing two blocks, a type 3 block copolymer (triblock) containing three blocks, and a type 4 block copolymer (tetrablock) containing four blocks. As for the polymer constituting one block, one type may be a polymer containing monomers, or two or more types may be copolymers containing monomers. For example, if a polymer block containing 1,3-butadiene is denoted as "B", a copolymer of 1,3-butadiene and isoprene is denoted as "B / I", a copolymer of 1,3-butadiene and styrene is denoted as "B / S", and a polymer block consisting of styrene is denoted as "S", then it is represented as a BB / I2 type block copolymer, a BB / S2 type block copolymer, an S-B2 type block copolymer, a BB / S-S3 type block copolymer, an SB-S3 type block copolymer, an SBS-B4 type block copolymer, etc.

[0316] In the above formula, the boundaries of each block do not necessarily need to be clearly distinguished. In addition, when one polymer block is a copolymer containing two types of monomers A and B, A and B in the block may be uniformly distributed or tapered.

[0317] Polymerization Branching Process

[0318] In the polymerization process of conjugated diene polymer (A) and conjugated diene polymer (B), a polymerization branching process may be included.

[0319] The polymerization branching process is a process for obtaining a conjugated diene-based polymer having a branched structure by polymerizing at least a conjugated diene compound, together with a vinyl aromatic compound as needed, using a polymerization initiator such as the organolithium compound described below, and adding a branching agent. Accordingly, in the polymerization branching process, the polymerization reaction of at least the conjugated diene compound and the aromatic vinyl compound is the main reaction before the addition of the branching agent, and the branching reaction is initiated after the addition of the branching agent.

[0320] As for the conjugated diene compound and vinyl aromatic compound used as monomers in the polymerization process, at least one of the conjugated diene compound and at least one of the vinyl aromatic compound described above may be used. Additionally, from the viewpoint of being able to introduce a nitrogen atom into the conjugated diene-based polymer, a derivative substituted to have at least one nitrogen atom within the molecule may be used as the conjugated diene compound or the vinyl aromatic compound described above.

[0321] As a polymerization initiator, organic lithium compounds such as organic monolithium compounds may be used, although not specifically limited.

[0322] Examples of organic monolithium compounds include, in terms of the bonding mode between the organic group and the lithium, compounds having carbon-lithium bonds, compounds having nitrogen-lithium bonds, and compounds having tin-lithium bonds.

[0323] Among them, the organic monolithium compound is preferably an organic lithium compound having at least one nitrogen atom in the molecule, in terms of being able to introduce a nitrogen atom into a conjugated diene polymer, and more preferably an alkyl lithium compound or dialkylaminolithium having a substituted amino group.

[0324] In addition, a substituted amino group is an amino group that does not have an active hydrogen in the amino group, or an amino group that has protected an active hydrogen in the amino group.

[0325] Examples of alkyl lithium compounds having an amino group that does not have the above active hydrogen include, but are not limited to, piperidinolithium, 3-dimethylaminopropyllithium, 3-diethylaminopropyllithium, 4-(methylpropylamino)butyllithium, and 4-hexamethyleneiminobutyllithium.

[0326] Examples of alkyl lithium compounds having an amino group that protects the active hydrogen include, but are not limited to, 3-bistrimethylsilylaminopropyllithium and 4-trimethylsilylmethylaminobutyllithium.

[0327] Examples of dialkylaminolithium include, but are not limited to, lithium dimethylamide, lithium diethylamide, lithium dipropylamide, lithium dibutylamide, lithium di-n-hexylamide, lithium diheptylamide, lithium diisopropylamide, lithium dioctylamide, lithium-di-2-ethylhexylamide, lithium didecylamide, lithium ethylpropylamide, lithium ethylbutylamide, lithium ethylbenzylamide, lithium methylphenethylamide, lithium hexamethyleneimide, lithium pyrrolidide, lithium piperidide, lithium heptamethyleneimide, lithium morpholide, 1-lithioazcyclooctane, 6-lithio-1,3,3-trimethyl-6-azabicyclo[3.2.1]octane, and 1-lithio-1,2,3,6-tetrahydropyridine, etc.

[0328] These organic monolithium compounds having substituted amino groups can also be used as organic monolithium compounds of solubilized oligomers by reacting a small amount of polymerizable monomers, such as 1,3-butadiene, isoprene, or styrene.

[0329] When a polymerization initiator has a nitrogen atom constituting an amino group, a chain transfer reaction is likely to occur when anionic polymerization proceeds, and the amount of coupling modifier reacting with the active end after the polymerization is completed tends to decrease. As a result, when using a polymerization initiator constituting a nitrogen atom constituting an amino group, the weight-average molecular weight tends to decrease.

[0330] Therefore, weight-average molecular weight 35×10 4 Above, 40×10 4 Above, 45×10 4 More than, or 60×10 4 In the case of the above relatively high molecular weight polymers, if one wishes to set a high modification rate, it is preferable to react nitrogen atoms at the polymerization end side rather than at the polymerization start end side. That is, polymers that are relatively high molecular weight and also contain nitrogen atoms at both ends tend to be difficult to manufacture. Depending on the weight average molecular weight and the structure of the coupling modifier, when nitrogen atoms are present only at the end side, the nitrogen content of the polymer is generally 3 mass ppm to 500 mass ppm.

[0331] From the perspective of ease of industrial availability and ease of controlling the polymerization reaction, alkyl lithium compounds may be used as organic monolithium compounds. When such organic monolithium compounds are used, a conjugated diene polymer having an alkyl group at the polymerization initiation end can be obtained.

[0332] Examples of alkyl lithium compounds include, but are not limited to the following: n-butyllithium, sec-butyllithium, tert-butyllithium, n-hexyllithium, benzyllithium, phenyllithium, and stilbenium, etc.

[0333] As alkyl lithium compounds, n-butyllithium and sec-butyllithium are preferred from the perspective of ease of industrial availability and ease of controlling the polymerization reaction.

[0334] These organic monolithium compounds may be used alone or in combination of two or more. In addition, they may be used in combination with other organometallic compounds.

[0335] Other organometallic compounds include, but are not limited to, alkaline earth metal compounds, alkali metal compounds other than lithium, and other organometallic compounds.

[0336] Alkaline earth metal compounds are not limited to the following, but examples include organic magnesium compounds, organic calcium compounds, and organic strontium compounds. In addition, compounds of alkaline earth metals such as alkoxides, sulfons, carbonates, and amides may also be examples.

[0337] Examples of organic magnesium compounds include, but are not limited to, dibutyl magnesium and ethylbutyl magnesium.

[0338] Other organometallic compounds include, but are not limited to, organoaluminum compounds.

[0339] It is preferable to determine the amount of polymerization initiator added based on the molecular weight of the desired conjugated diene polymer. The number-average molecular weight and / or weight-average molecular weight can be controlled by the ratio of the amount of monomer added to the amount of polymerization initiator added. Specifically, if the ratio of the amount of polymerization initiator added is reduced, the molecular weight tends to increase, and if the ratio of the amount of polymerization initiator added is increased, the molecular weight tends to decrease.

[0340] From the perspective of reliably and easily obtaining conjugated diene polymer (A) and conjugated diene polymer (B), it is preferable to carry out the polymerization process in an inert solvent. Such inert solvents are not limited to the following, but examples include hydrocarbon solvents such as saturated hydrocarbons and aromatic hydrocarbons. Specific hydrocarbon solvents are not limited to the following, but examples include aliphatic hydrocarbons such as butane, pentane, hexane, and heptane; alicyclic hydrocarbons such as cyclopentane, cyclohexane, methylcyclopentane, and methylcyclohexane; aromatic hydrocarbons such as benzene, toluene, and xylene; and hydrocarbons including mixtures thereof.

[0341] With regard to obtaining a conjugated diene polymer in which a conjugated diene compound and a vinyl aromatic compound are randomly polymerized, the polymerization reaction in the polymerization process may use the following method, for example, as described in Japanese Patent Publication No. 59-140211. That is, a method may be used in which the entire amount of the vinyl aromatic compound and a portion of the conjugated diene compound are first used to initiate the polymerization reaction, and then the remaining conjugated diene compound is added intermittently during the polymerization reaction.

[0342] The polymerization temperature in the polymerization reaction of the polymerization process is not particularly limited, but it is preferably a temperature at which living anionic polymerization proceeds. Furthermore, from the perspective of improving productivity, it is more preferable for the temperature to be 0°C or higher, and even more preferable for it to be 0°C or higher and 120°C or lower. When the polymerization temperature in the polymerization reaction is within the above range, there is a tendency to sufficiently increase the reactivity with the coupling modifier in the coupling process described later. From the same perspective, the polymerization temperature in the polymerization reaction is even more preferably 50°C or higher and 100°C or lower.

[0343] In the polymerization process, a polar compound may be added. When a polar compound is added, there is a tendency to obtain a conjugated diene polymer in which the vinyl aromatic compound and the conjugated diene compound are copolymerized more randomly. As such, since the polar compound has an effective randomization effect in the copolymerization of the conjugated diene compound and the vinyl aromatic compound, it can be used as an agent to control the distribution of the vinyl aromatic compound or to control the amount of styrene blocks. In addition, the polar compound can promote the polymerization reaction and can also be used as a vinylizing agent to control the microstructure of the conjugated diene polymer.

[0344] As such, since polar compounds are used as vinylizing agents, randomizing agents, and polymerization promoters, reducing the amount of polar compounds to adjust, for example, the vinylization rate or randomization rate tends to reduce the polymerization-promoting effect as well. Therefore, in the method of adjusting the degree of branching of a polymer by reacting a coupling modifier with the polymerization end, if the amount of polar compound added is reduced, the polymerization time becomes longer and the proportion of inactivated polymerization end. Consequently, it tends to be difficult to increase the modification rate using such a method. In other words, when attempting to adjust the degree of branching of a modified conjugated diene polymer by adjusting the amount of polar compound added and reacting with a coupling modifier, it tends to be difficult to control the vinylization rate or randomization rate. In this regard, the manufacturing method of the present embodiment is advantageous for the structural design of conjugated diene polymers because the degree of branching of the polymer can be increased by the branching agent described below, thereby allowing the degree of branching to be controlled independently of the vinylization rate or randomization rate.

[0345] Examples of polar compounds include, but are not limited to the following: ethers such as tetrahydrofuran, diethyl ether, dioxane, ethylene glycol dimethyl ether, ethylene glycol dibutyl ether, diethylene glycol dimethyl ether, diethylene glycol dibutyl ether, dimethoxybenzene, and 2,2-bis(2-oxolanyl)propane; tertiary amine compounds such as tetramethylethylenediamine, dipiperidinoethane, trimethylamine, triethylamine, pyridine, and quinuclideine; alkali metal alkoxide compounds such as potassium-tert-amylate, potassium-tert-butyrate, sodium-tert-butyrate, and sodium amylate; and phosphine compounds such as triphenylphosphine. These polar compounds may be used individually or in combination of two or more.

[0346] The amount of polar compound added is not particularly limited, but can be adjusted according to the amount of polymerization active ends, that is, the amount of polymerization initiator added. For example, regarding the amount of polar compound added, it is preferable to have an amount of 0.010 moles or more and 1.0 moles or less per 1 mole of polymerization initiator, and more preferable to have an amount of 0.10 moles or more and 0.70 moles or less. Within the above range, the amount of polar compound added may be 0.60 moles or less or 0.50 moles or less per 1 mole of polymerization initiator. Alternatively, it may be 0.15 moles or more or 0.20 moles or more per 1 mole of polymerization initiator. If the amount of polar compound added is below the above upper limit, a conjugated diene polymer with a low Tg tends to be obtained. Furthermore, if the amount of polar compound added is above the above lower limit, the deactivation of polymerization active ends is suppressed, and the coupling rate in the coupling process described later tends to improve. The amount of polar compound added may be within a range obtained by arbitrarily combining the upper and lower limits mentioned above.

[0347] In the method for manufacturing conjugated diene polymers (A) and (B), a process for removing impurities may be included prior to the polymerization process. In particular, when allenes and acetylenes are included as impurities in the monomer, polymerization initiator, and / or inert solvent described above, it is preferable to include a process for removing impurities prior to the polymerization process. By including a process for removing impurities, a conjugated diene polymer having a high concentration of active ends tends to be obtained, and a modified conjugated diene polymer with a high modification rate tends to be obtained in the coupling process described later. Such an impurity removal process is not particularly limited, but, for example, a process of treatment with an organometallic compound may be cited. Such an organometallic compound is not particularly limited, but, for example, an organolithium compound may be cited, and such an organolithium compound is not particularly limited, but, for example, n-butyllithium may be cited.

[0348] In the polymerization branching process, the branching reaction in the conjugated diene polymer is initiated by adding a branching agent described below. After the branching agent is added, the polymerization reaction in which the conjugated diene polymer grows and the branching reaction in which the conjugated diene polymer branches occur in competition within the reaction system. Therefore, by adjusting the type and amount of the branching agent, as well as the timing of its addition, it is possible to control the weight-average molecular weight, number-average molecular weight, their ratio (Mw / Mn), and absolute molecular weight of the conjugated diene polymer obtained in the polymerization branching process, as well as the degree of branching of the conjugated diene polymer, the number of branching points, and the number of branches at the branching points.

[0349] In addition, by adding a branching agent during the polymerization of a conjugated diene polymer, the total amount of active ends of the conjugated diene polymer in the reaction system can be reduced relative to the amount of polymerization initiator added, so that the added polar compound promotes the reaction at least during the initial stages of polymerization, thereby maintaining the activity of the polymerization active ends. As a result, for the conjugated diene polymer of the present embodiment in which the unit amount of bound vinyl aromatic monomer and the vinyl bond amount are within the aforementioned predetermined ranges, the coupling rate and / or modification rate of the polymerization end can be easily improved. However, it is not necessary to react the conjugated diene polymer of the present embodiment with a coupling modifying agent.

[0350] As described above, in the method for manufacturing conjugated diene polymers (A) and (B), the amount of a polar compound added can be adjusted for the purpose of controlling microstructures such as the amount of bound vinyl aromatic monomer units and the amount of vinyl bonds. The amount of a polar compound typically added to achieve the amount of bound vinyl aromatic monomer units and the amount of vinyl bonds within the aforementioned predetermined range is insufficient from the perspective of maintaining the active end of the conjugated diene polymer within the reaction system when a branching agent is not added, and it is not easy to sufficiently maintain the activity of the polymerization active end. Furthermore, with such an amount of polar compound added, the randomization ability for vinyl aromatic compounds and conjugated diene compounds is not sufficiently high, so in conjugated diene polymers where the amount of bound vinyl aromatic monomer units and the amount of vinyl bonds are within the aforementioned predetermined range, the polymerization end tends to become a vinyl aromatic monomer unit. Under such conditions, it tends to be difficult to obtain conjugated diene polymers with high coupling or modification rates.

[0351] That is, in the method for manufacturing conjugated diene polymers (A) and conjugated diene polymers (B), when a branching agent is used, even with an amount of polar compound added, which is usually not easy to sufficiently maintain the activity of the polymerization active end, the active end of the polymer can be sufficiently maintained, and a high coupling rate and modification rate can be achieved.

[0352] In the branching process, the timing of adding the branching agent is not particularly limited and can be appropriately selected depending on the use of the conjugated diene polymer being manufactured.

[0353] In terms of improving the absolute molecular weight of the obtained conjugated diene polymer and improving the modification rate in the coupling process, the timing for adding the branching agent is preferably when the raw material conversion rate is 20% or higher after the addition of the polymerization initiator, more preferably when it is 40% or higher, even more preferably when it is 50% or higher, even more preferably when it is 65% or higher, and even more preferably when it is 75% or higher. That is, the timing for adding the branching agent is preferably when the polymerization reaction is sufficiently stable. By setting the timing for adding the branching agent within the above range, a conjugated diene polymer with a higher modification rate in the coupling process can be obtained even with a small amount of polar compound added or without adding it.

[0354] As a branching agent, compounds represented by the following formula (10) or formula (11) may be used, although not specifically limited.

[0355]

[0356]

[0357] (In Equation (10), R 1 It may represent a hydrogen atom or 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 a part thereof.

[0358] R 2 to R 3 Each may independently represent 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 a part thereof.

[0359] R in the case where multiple exist 2 to R 3 Each is independent.

[0360] X 1 represents an independent halogen atom.

[0361] m represents an integer from 0 to 2, n represents an integer from 0 to 3, and l represents an integer from 0 to 3.

[0362] (m+n+l) represents 3.

[0363] (In Equation (11), R 4 to R 7 Each may independently represent 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 a part thereof.

[0364] R in the case where multiple exist 4 to R 7 Each is independent.

[0365] X 2 To X 3 Silver represents an independent halogen atom.

[0366] m represents an integer from 0 to 2, n represents an integer from 0 to 3, and l represents an integer from 0 to 3.

[0367] (m+n+l) represents 3.

[0368] a represents an integer from 0 to 3, b represents an integer from 0 to 2, and c represents an integer from 0 to 3. (a+b+c) represents 3.)

[0369] In this embodiment, the branching agent used when constructing the main chain branching structure of the conjugated diene polymer is R of the above formula (10) in terms of polymerization continuity and improved branching degree. 1 It is desirable that this is a hydrogen atom and a compound with m=0.

[0370] In addition, in this embodiment, the branching agent used when constructing the main chain branching structure of the conjugated diene polymer is preferably a compound in which m=0 and b=0 in the above formula (11) from the perspective of improving the degree of branching.

[0371] In addition, in this embodiment, the branching agent used when constructing the main chain branching structure of the conjugated diene polymer is R of the above formula (10) in terms of polymerization continuity, modification rate, and improvement of branching degree. 1 It is more desirable that this be a hydrogen atom, and that it be a compound where m=0 and l=0.

[0372] In addition, in this embodiment, the branching agent used when constructing the main chain branching structure of the conjugated diene polymer is more preferably a compound of m=0, l=0, a=0, b=0 in the above formula (11) in order to improve the modification rate and degree of branching.

[0373] In addition, in this embodiment, the branching agent used when constructing the main chain branching structure of the conjugated diene polymer is R in the above formula (10) in terms of polymerization continuity, modification rate, and improvement of branching degree. 1 It is more preferable that it be a compound in which the atom is hydrogen, l=0, and n=3.

[0374] The branching agent represented by the above formula (10) is not limited to the following, but includes, for example, trimethoxy(4-vinylphenyl)silane, triethoxy(4-vinylphenyl)silane, tripropoxy(4-vinylphenyl)silane, tributoxy(4-vinylphenyl)silane, triisopropoxy(4-vinylphenyl)silane, trimethoxy(3-vinylphenyl)silane, triethoxy(3-vinylphenyl)silane, tributoxy(3-vinylphenyl)silane, triisopropoxy(3-vinylphenyl)silane, trimethoxy(2-vinylphenyl)silane, triethoxy(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, 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, Examples include dimethyl ethoxy(4-vinylphenyl) silane, dimethyl propoxy(4-vinylphenyl) silane, dimethyl butoxy(4-vinylphenyl) silane, dimethyl isopropoxy(4-vinylphenyl) silane, dimethyl methoxy(3-vinylphenyl) silane, dimethyl ethoxy(3-vinylphenyl) silane, dimethyl propoxy(3-vinylphenyl) silane, dimethyl butoxy(3-vinylphenyl) silane, dimethyl isopropoxy(3-vinylphenyl) silane, dimethyl methoxy(2-vinylphenyl) silane, dimethyl ethoxy(2-vinylphenyl) silane, dimethyl propoxy(2-vinylphenyl) silane, dimethyl butoxy(2-vinylphenyl) silane, and dimethyl isopropoxy(2-vinylphenyl) silane.

[0375] In addition, as a branching agent represented by the above formula (10), trimethoxy(4-isopropenphenyl)silane, triethoxy(4-isopropenphenyl)silane, tripropoxy(4-isopropenphenyl)silane, tributoxy(4-isopropenphenyl)silane, triisopropoxy(4-isopropenphenyl)silane, trimethoxy(3-isopropenphenyl)silane, triethoxy(3-isopropenphenyl)silane, tripropoxy(3-isopropenphenyl)silane, tributoxy(3-isopropenphenyl)silane, triisopropoxy(3-isopropenphenyl)silane, trimethoxy(2-isopropenphenyl)silane, triethoxy(2-isopropenphenyl)silane, tripropoxy(2-isopropenphenyl)silane, tributoxy(2-isopropenphenyl)silane, Triisopropoxy(2-isopropenphenyl)silane, dimethoxymethyl(4-isopropenphenyl)silane, diethoxymethyl(4-isopropenphenyl)silane, dipropoxymethyl(4-isopropenphenyl)silane, dibutoxymethyl(4-isopropenphenyl)silane, diisopropoxymethyl(4-isopropenphenyl)silane, dimethoxymethyl(3-isopropenphenyl)silane, diethoxymethyl(3-isopropenphenyl)silane, dipropoxymethyl(3-isopropenphenyl)silane, dibutoxymethyl(3-isopropenphenyl)silane, diisopropoxymethyl(3-isopropenphenyl)silane, dimethoxymethyl(2-isopropenphenyl)silane, diethoxymethyl(2-isopropenphenyl)silane, dipropoxymethyl(2-isopropenphenyl)silane, Dibutoxymethyl(2-isopropenphenyl)silane, diisopropoxymethyl(2-isopropenphenyl)silane, dimethylmethoxy(4-isopropenphenyl)silane, dimethylethoxy(4-isopropenphenyl)silane, dimethylpropoxy(4-isopropenphenyl)silane, dimethylbutoxy(4-isopropenphenyl)silane, dimethylisopropoxy(4-isopropenphenyl)silane, dimethylisopropoxy(4-isopropenphenyl)silane, dimethylmethoxy(3-isopropenphenyl)silane, dimethylethoxy(3-isopropenphenyl)silane, dimethylpropoxy(3-isopropenphenyl)silane, dimethylbutoxy(3-isopropenphenyl)silane, dimethylisopropoxy(3-isopropenphenyl)silane, dimethylmethoxy(2-isopropenphenyl)silane, dimethylethoxy(2-isopropenphenyl)silane, Dimethylpropoxy(2-isopropenylphenyl)silane,Dimethylbutoxy(2-isopropenphenyl)silane, dimethylisopropoxy(2-isopropenphenyl)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, dibromomethyl(2-vinylphenyl)silane, dimethylchloro(4-vinylphenyl)silane, dimethylchloro(3-vinylphenyl)silane, dimethylchloro(2-vinylphenyl)silane, Examples include dimethylbromo(4-vinylphenyl)silane, dimethylbromo(3-vinylphenyl)silane, and dimethylbromo(2-vinylphenyl)silane.

[0376] Among these, 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, tributoxy(3-vinylphenyl)silane, triisopropoxy(3-vinylphenyl)silane, and trichloro(4-vinylphenyl)silane are preferred, and trimethoxy(4-vinylphenyl)silane, triethoxy(4-vinylphenyl)silane, tripropoxy(4-vinylphenyl)silane, tributoxy(4-vinylphenyl)silane, and triisopropoxy(4-vinylphenyl)silane are more preferred.

[0377] The branching agent represented by the above formula (11) is not limited to the following, but includes, for example, 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, Examples include 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.

[0378] Among these, 1,1-bis(4-trimethoxysilylphenyl)ethylene, 1,1-bis(4-triethoxysilylphenyl)ethylene, 1,1-bis(4-tripropoxysilylphenyl)ethylene, 1,1-bis(4-tripentoxysilylphenyl)ethylene, and 1,1-bis(4-triisopropoxysilylphenyl)ethylene are preferred, and 1,1-bis(4-trimethoxysilylphenyl)ethylene is more preferred.

[0379] The amount of such branching agent added is not particularly limited and can be appropriately selected depending on the intended use of the conjugated diene polymer, but it is preferable that the amount is 0.020 moles or more and 0.50 moles or less per 1 mole of polymerization initiator, and more preferable that the amount is 0.025 moles or more and 0.40 moles or less.

[0380] The amount of branching agent added may be 0.030 moles or more or 0.035 moles or more per 1 mole of polymerization initiator within the above range. Alternatively, it may be 0.30 moles or less or 0.25 moles or less per 1 mole of polymerization initiator.

[0381] The amount of branching agent added may be within a range obtained by arbitrarily combining the upper and lower limits mentioned above. The amount of branching agent added affects the degree of branching of the entire conjugated diene polymer, and as the amount added increases, the overall degree of branching and the degree of branching at extreme values ​​increase.

[0382] In the polymerization branching process, the reaction temperature may or may not be changed after adding the branching agent.

[0383] In the polymerization branching process, after adding the branching agent, additional monomers that are raw materials for conjugated diene polymers may be added, additionally, branching agents may be added thereafter, and the addition of branching agents and monomers may be repeated.

[0384] The additional monomer is not particularly limited, but from the perspective of improving the modification rate in the coupling process, it is preferable to add the same monomer that was initially added as a monomer in the polymerization branching process.

[0385] The amount of additional monomer may be 1.0% or more, 5.0% or more, 10% or more, 15% or more, or 20% or more of the total amount used as monomer for the conjugated diene polymer. In addition, the amount of additional monomer may be 50% or less, 40% or less, or 35% or less.

[0386] If the amount of monomer added is within the above range, the molecular weight between the branching point generated by adding a branching agent and the branching point generated by adding a coupling modifier becomes longer, so it tends to take on a molecular structure with high linearity. By making the obtained conjugated diene polymer into such a structure, when vulcanized, the entanglement between the molecular chains of the conjugated diene polymer increases, and it tends to take on a vulcanized product with excellent wear resistance, maneuverability, and fracture strength.

[0387] (Coupling process)

[0388] In the method for manufacturing a conjugated diene polymer according to the present embodiment, the conjugated diene polymer having a branched structure obtained by the polymerization branching process described above may be reacted with a coupling modifier to form a modified conjugated diene polymer. Through such a coupling process, the conjugated diene polymer having a branched structure obtained by the polymerization branching process can be modified by a nitrogen atom-containing functional group having affinity or binding reactivity to the filler. Additionally, multiple conjugated diene polymers can be coupled.

[0389] As a coupling modifier, it is not particularly limited to a reactive compound having two or more functional groups that have a nitrogen atom-containing functional group having affinity or binding reactivity to the filler and can react with the active end of the conjugated diene polymer.

[0390] Examples of such coupling modifiers include coupling modifiers that contain nitrogen atoms, and furthermore, groups containing nitrogen atoms and silicon atoms.

[0391] Examples of coupling modifiers having a group containing a nitrogen atom include, but are not limited to, isocyanato compounds, isothiocyanato compounds, isocyanuric acid derivatives, carbonyl compounds containing a nitrogen atom, vinyl compounds containing a nitrogen atom, epoxy compounds containing a nitrogen atom, imine compounds, and alkoxysilane compounds containing a nitrogen atom.

[0392] Examples of coupling modifiers having a group containing a nitrogen atom include amine compounds that do not have active hydrogen, protected amine compounds in which active hydrogen is substituted with a protecting group, imine compounds having the general formula -N=C, and alkoxysilane compounds combined with these nitrogen-containing compounds. Examples of amine compounds that do not have active hydrogen include tertiary amine compounds.

[0393] Examples of isocyanato compounds include, but are not limited to, 2,4-tolylene diisocyanato, 2,6-tolylene diisocyanato, diphenylmethane diisocyanato, polymeric type diphenylmethane diisocyanato (C-MDI), phenyl isocyanato, isophorone diisocyanato, hexamethylene diisocyanato, butyl isocyanato, and 1,3,5-benzene triisocyanato.

[0394] Examples of isothiocyanate compounds include, but are not limited to, 2,4-tolylene diisothiocyanate, 2,6-tolylene diisothiocyanate, diphenylmethane diisothiocyanate, phenyl isothiocyanate, isophorone diisothiocyanate, hexamethylene diisothiocyanate, butyl isothiocyanate, and 1,3,5-benzene triisothiocyanate.

[0395] Examples of isocyanuric acid derivatives include, but are not limited to the following: 1,3,5-tris(3-trimethoxysilylpropyl)isocyanurate, 1,3,5-tris(3-triethoxysilylpropyl)isocyanurate, 1,3,5-tri(oxiran-2-yl)-1,3,5-triazinan-2,4,6-trione, and 1,3,5-tris(isocyanatomethyl)-1,3,5-triazinan-2,4,6-trione, and 1,3,5-trivinyl-1,3,5-triazinan-2,4,6-trione.

[0396] As nitrogen atom-containing carbonyl compounds, examples include, but are not limited to: 1,3-dimethyl-2-imidazolidinone, 1-methyl-3-ethyl-2-imidazolidinone, 1-methyl-3-(2-methoxyethyl)-2-imidazolidinone, N-methyl-2-pyrrolidone, N-methyl-2-piperidone, N-methyl-2-quinolone, 4,4'-bis(diethylamino)benzophenone, 4,4'-bis(dimethylamino)benzophenone, methyl-2-pyridylketone, methyl-4-pyridylketone, propyl-2-pyridylketone, di-4-pyridylketone, 2-benzoylpyridine, N,N,N',N'-tetramethylurea, N,N-dimethyl-N',N'-diphenylurea, N,N-methyl diethylcarbamate, Examples include N,N-diethylacetamide, N,N-dimethyl-N',N'-dimethylaminoacetamide, N,N-dimethylpicolinamide, and N,N-dimethylisonicotinamide.

[0397] Examples of nitrogen atom-containing vinyl compounds include, but are not limited to, N,N-dimethylacrylamide, N,N-dimethylmethacrylamide, N-methylmaleimide, N-methylphthalimide, N,N-bistrimethylsilylacrylamide, morpholinoacrylamide, 3-(2-dimethylaminoethyl)styrene, (dimethylamino)dimethyl-4-vinylphenylsilane, 4,4'-vinylidenebis(N,N-dimethylaniline), 4,4'-vinylidenebis(N,N-diethylaniline), 1,1-bis(4-morpholinophenyl)ethylene, and 1-phenyl-1-(4-N,N-dimethylaminophenyl)ethylene.

[0398] Examples of nitrogen atom-containing epoxy compounds include, but are not limited to, hydrocarbon compounds containing an epoxy group bonded to an amino group.

[0399] In addition, the hydrocarbon compound containing an epoxy group bonded to the amino group may further have an epoxy group bonded to an ether group. Examples of such nitrogen atom-containing epoxy compounds include, but are not limited to, compounds represented by the following formula (12).

[0400]

[0401] In the above formula (12), R is a divalent or higher organic group having at least one polar group selected from a divalent or higher hydrocarbon group, a polar group having oxygen such as ether, epoxy, ketone, etc., a polar group having sulfur such as thioether, thioketone, etc., a polar group having nitrogen such as a tertiary amino group, an imino group, etc.

[0402] The hydrocarbon group with two or more valence groups is a hydrocarbon group that may be saturated or unsaturated, straight-chain, branched, or cyclic, and includes alkylene groups, alkenylene groups, phenylene groups, etc. Preferably, it is a hydrocarbon group having 1 to 20 carbon atoms. Examples include methylene, ethylene, butylene, cyclohexylene, 1,3-bis(methylene)-cyclohexane, 1,3-bis(ethylene)-cyclohexane, o-, m-, p-phenylene, m-, p-xylene, bis(phenylene)-methane, etc.

[0403] Among the above equation (12), R 24 , R 27 is a hydrocarbon group having 1 to 10 carbon atoms, and R 24 , R 27 They may be identical or different from each other.

[0404] Among the above equation (12), R 25 , R 28 is hydrogen or a hydrocarbon group having 1 to 10 carbon atoms, and R 25 , R 28They may be identical or different from each other.

[0405] Among the above equation (12), R 26 It is a hydrocarbon group having 1 to 10 carbon atoms, or a structure of the following formula (13).

[0406] R 24 , R 25 , R 26 It may be a combined fantasy structure.

[0407] Also, R 26 In the case of this hydrocarbon group, it may be a cyclic structure bonded to R. In the case of the above cyclic structure, R 26 It may be in the form where N and R are directly bonded to each other.

[0408] In the above equation (12), f is an integer greater than or equal to 1, and g is an integer greater than or equal to 0 or 1.

[0409]

[0410] Among the above equation (13), R 29 , R 30 R of the above equation (12) 24 , R 25 Defined similarly to, and R 29 , R 30 They may be identical or different from each other.

[0411] The nitrogen atom-containing epoxy compound described above is preferably a nitrogen atom-containing epoxy compound having one or more diglycidyl amino groups in the molecule and one or more glycidoxy groups.

[0412] Nitrogen atom-containing epoxy compounds are not limited to the following, but include, for example, N,N-diglycidyl-4-glycidoxycyaniline, 1-N,N-diglycidylaminomethyl-4-glycidoxy-cyclohexane, 4-(4-glycidoxyphenyl)-(N,N-diglycidyl)aniline, 4-(4-glycidoxyphenoxy)-(N,N-diglycidyl)aniline, 4-(4-glycidoxybenzyl)-(N,N-diglycidyl)aniline, 4-(N,N'-diglycidyl-2-piperazinyl)-glycidoxybenzene, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, N,N,N',N'-tetraglycidyl-m-xylenediamine, 4,4-methylene-bis(N,N-diglycidylaniline), Examples include 1,4-bis(N,N-diglycidylamino)cyclohexane, N,N,N',N'-tetraglycidyl-p-phenylenediamine, 4,4'-bis(diglycidylamino)benzophenone, 4-(4-glycidylpiperazinyl)-(N,N-diglycidyl)aniline, 2-〔2-(N,N-diglycidylamino)ethyl〕-1-glycidylpyrrolidine, N,N-diglycidylaniline, 4,4'-diglycidyl-dibenzylmethylamine, N,N-diglycidylaniline, N,N-diglycidylorthotoluidine, and N,N-diglycidylaminomethylcyclohexane.

[0413] Among these, N,N-diglycidyl-4-glycidoxianiline and 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane are preferred.

[0414] As imine compounds that are coupling modifiers having a group containing a nitrogen atom, examples include, but are not limited to: N-butylpropane-2-imine, N-butyl-4-methylpentane-2-imine, N,N'-(propane-1,3-diyl)bis(4-methylpentane-2-imine), N,N'-(hexane-1,6-diyl)bis(4-methylpentane-2-imine), tris[2-(propane-2-ylideneamino)ethyl]amine, tris[2-(propane-2-ylideneamino)propyl]amine, N,N'-(1,4-phenylene)bis(4-methylpentane-2-imine), 1,1'-(1,4-phenylene)bis(N-propylethane-1-imine), N,N'-(propane-1,3-diyl)bis(1-phenylmethaneimine), N,N'-(hexane 1,6-diyl)bis(1-phenylmethaneimine) can be an example.

[0415] As nitrogen atom-containing alkoxysilane compounds that are coupling modifiers having a group containing a nitrogen atom, examples include, but are not limited to: 3-dimethylaminopropyltrimethoxysilane, 3-dimethylaminopropylmethyldimethoxysilane, 3-diethylaminopropyltriethoxysilane, 3-morpholinopropyltrimethoxysilane, 3-piperidinopropyltriethoxysilane, 3-hexamethyleneiminopropylmethyldiethoxysilane, 3-(4-methyl-1-piperazino)propyltriethoxysilane, 3-(4-methyl-1-piperazino)propyltrimethoxysilane, 1-[3-(triethoxysilyl)-propyl]-3-methylhexahydropyrimidine, 3-(4-trimethylsilyl-1-piperazino)propyltriethoxysilane, 3-(3-triethylsilyl-1-imidazolidinyl)propylmethyldiethoxysilane, 3-(3-trimethylsilyl-1-hexahydropyrimidinyl)propyltrimethoxysilane, 3-dimethylamino-2-(dimethylaminomethyl)propyltrimethoxysilane, bis(3-dimethoxymethylsilylpropyl)-N-methylamine, bis(3-trimethoxysilylpropyl)-N-methylamine, bis(3-triethoxysilylpropyl)methylamine, tris(trimethoxysilyl)amine, tris(3-trimethoxysilylpropyl)amine, N,N,N',N'-tetra(3-trimethoxysilylpropyl)ethylenediamine, 3-isocyanatopropyltrimethoxysilane, 3-cyanopropyltrimethoxysilane, 2,2-Dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza-2-silacyclopentane, 2,2-diethoxy-1-(3-triethoxysilylpropyl)-1-aza-2-silacyclopentane, 2,2-Dimethoxy-1-(4-trimethoxysilylbutyl)-1-aza-2-silacyclohexane, 2,2-Dimethoxy-1-(3-dimethoxymethylsilylpropyl)-1-aza-2-silacyclopentane, 2,2-Dimethoxy-1-phenyl-1-aza-2-silacyclopentane, 2,2-diethoxy-1-butyl-1-aza-2-silacyclopentane, 2,2-Dimethoxy-1-methyl-1-aza-2-silacyclopentane, Examples include 2,2-dimethoxy-8-(4-methylpiperazinyl)methyl-1,6-dioxa-2-silacyclooctane and 2,2-dimethoxy-8-(N,N-diethylamino)methyl-1,6-dioxa-2-silacyclooctane.

[0416] Preferred nitrogen atom-containing alkoxysilane compounds are, but are not limited to the following, examples include 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 (also referred to as "N,N,N',N'-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-2-trimethylsilyl-1-sila-2-azacyclopentane)propyl]silane, 3-tris[2-(2,2-dimethoxy-1-aza-2-silacyclopentane)ethoxy]silyl-1-trimethoxysilylpropane,1-[3-(1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane)propyl]-3,4,5-tris(3-trimethoxysilylpropyl)-cyclohexane, 1-[3-(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, tris[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]phosphate, N-(1,3-dimethylbutylidene)-3-(triethoxysilyl)-1-propanamine, N-(1,3-dimethylbutylidene)-3-(trimethoxysilyl)-1-propanamine, N-benzylidene-3-(triethoxysilyl)propan-1-amine, N-benzylidene-3-(trimethoxysilyl)propan-1-amine, 1,1-(1,4-phenylene)bis(N-(3(triethoxysilyl)propyl)methaneamine), Examples include 1,1-(1,4-phenylene)bis(N-(3(trimethoxysilyl)propyl)methaneamine), 2-methoxy-2-methyl-1-(benzylideneaminoethyl)-1-aza-2-silacyclopentane, and 2-methoxy-2-methyl-1-(4-methoxybenzylideneaminoethyl)-1-aza-2-silacyclopentane.

[0417] Among coupling modifiers having a group containing a nitrogen atom, examples of protected amine compounds in which active hydrogen is substituted with a protecting group include compounds having an unsaturated bond and a protected amine in the molecule. Such compounds include, but are not limited to the following, examples: 4,4'-vinylidenebis[N,N-bis(trimethylsilyl)aniline], 4,4'-vinylidenebis[N,N-bis(triethylsilyl)aniline], 4,4'-vinylidenebis[N,N-bis(t-butyldimethylsilyl)aniline], 4,4'-vinylidenebis[N-methyl-N-(trimethylsilyl)aniline], 4,4'-vinylidenebis[N-ethyl-N-(trimethylsilyl)aniline], 4,4'-vinylidenebis[N-methyl-N-(triethylsilyl)aniline], 4,4'-vinylidenebis[N-ethyl-N-(triethylsilyl)aniline], Examples include 4,4'-vinylidenebis[N-methyl-N-(t-butyldimethylsilyl)aniline], 4,4'-vinylidenebis[N-ethyl-N-(t-butyldimethylsilyl)aniline], 1-[4-N,N-bis(trimethylsilyl)aminophenyl]-1-[4-N-methyl-N-(trimethylsilyl)aminophenyl]ethylene and 1-[4-N,N-bis(trimethylsilyl)aminophenyl]-1-[4-N,N-dimethylaminophenyl]ethylene.

[0418] Among coupling modifiers having a group containing a nitrogen atom, examples of protected amine compounds in which active hydrogen is substituted with a protecting group include alkoxysilane and compounds having a protected amine in the molecule.

[0419] Such compounds include, but are not limited to the following, examples: N,N-bis(trimethylsilyl)aminopropyltrimethoxysilane, N,N-bis(trimethylsilyl)aminopropylmethyldimethoxysilane, N,N-bis(trimethylsilyl)aminopropyltriethoxysilane, N,N-bis(trimethylsilyl)aminopropylmethyldiethoxysilane, N,N-bis(trimethylsilyl)aminoethyltrimethoxysilane, N,N-bis(trimethylsilyl)aminoethylmethyldiethoxysilane, N,N-bis(triethylsilyl)aminopropylmethyldiethoxysilane, 3-(4-trimethylsilyl-1-piperazino)propyltriethoxysilane, 3-(3-triethylsilyl-1-imidazolidinyl)propylmethyldiethoxysilane, 3-(3-trimethylsilyl-1-hexahydropyrimidinyl)propyltrimethoxysilane, 2,2-Dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza-2-silacyclopentane, 2,2-diethoxy-1-(3-triethoxysilylpropyl)-1-aza-2-silacyclopentane, 2,2-Dimethoxy-1-(4-trimethoxysilylbutyl)-1-aza-2-silacyclohexane, 2,2-Dimethoxy-1-(3-dimethoxymethylsilylpropyl)-1-aza-2-silacyclopentane, 2,2-Dimethoxy-1-phenyl-1-aza-2-silacyclopentane, 2,2-diethoxy-1-butyl-1-aza-2-silacyclopentane, 2,2-Dimethoxy-1-methyl-1-aza-2-silacyclopentane, Examples include N-(1,3-dimethylbutylidene)-3-methyl(dimethoxysilyl)-1-propanamine, N-(1,3-dimethylbutylidene)-3-methyl(diethoxysilyl)-1-propanamine, N-(1-methylethylidene)-3-(triethoxysilyl)-1-propanamine, N-(1-methylethylidene)-3-(trimethoxysilyl)-1-propanamine, N-(1-methylethylidene)-3-methyl(dimethoxysilyl)-1-propanamine, N-(1-methylethylidene)-3-methyl(diethoxysilyl)-1-propanamine, N-ethylidene-3-(triethoxysilyl)-1-propanamine, and N-ethylidene-3-(trimethoxysilyl)-1-propanamine.

[0420] In addition, N-ethylidene-3-methyl(dimethoxysilyl)-1-propanamine, N-ethylidene-3-methyl(diethoxysilyl)-1-propanamine, N-(1-methylpropylidene)-3-(triethoxysilyl)-1-propanamine, N-(1-methylpropylidene)-3-(trimethoxysilyl)-1-propanamine, N-(1-methylpropylidene)-3-methyl(dimethoxysilyl)-1-propanamine, N-(1-methylpropylidene)-3-methyl(diethoxysilyl)-1-propanamine, N-benzylidene-3-methyl(dimethoxysilyl)propan-1-amine, N-benzylidene-3-methyl(diethoxysilyl)propan-1-amine, N-4-methylbenzylidene-3-(triethoxysilyl)propan-1-amine, N-4-methylbenzylidene-3-(trimethoxysilyl)propane-1-amine, N-4-methylbenzylidene-3-methyl(dimethoxysilyl)propane-1-amine, N-4-methylbenzylidene-3-methyl(diethoxysilyl)propane-1-amine, N-naphthylidene-3-(triethoxysilyl)propane-1-amine, N-naphthylidene-3-(trimethoxysilyl)propane-1-amine, N-naphthylidene-3-methyl(dimethoxysilyl)propane-1-amine, 1,1-(1,4-phenylene)bis(N-(3-methyl(dimethoxysilyl)propyl)methaneamine), 1,1-(1,4-phenylene)bis(N-(3-methyl(diethoxysilyl)propyl)methaneamine), Examples include 2-ethoxy-2-methyl-1-(benzylideneaminoethyl)-1-aza-2-silacyclopentane and 2-methoxy-2-methyl-1-(methylisobutylideneaminoethyl)-1-aza-2-silacyclopentane.

[0421] In the coupling process, two or more types of nitrogen atom-containing alkoxysilane compounds represented by any of the following formulas (14) to (18) may be used as coupling modifiers.

[0422] As such coupling modifiers, a coupling modifier having two or fewer alkoxysilyl groups and a coupling modifier having more than two alkoxysilyl groups can be used in combination.

[0423]

[0424] In Equation (14), R 8 to R 10is a hydrocarbon group having 1 to 20 carbon atoms, may have unsaturated bonds, and may each be the same or different. R 11 , R 12 is an aliphatic hydrocarbon group having 1 to 6 carbon atoms, may have unsaturated bonds, and may each be the same or different, and R 13 It is a hydrocarbon group having 1 to 20 carbon atoms that may be substituted with an organic group that does not have active hydrogen and contains Si, O, or N, and may have unsaturated bonds. d is an integer from 1 to 3.

[0425]

[0426] In Equation (15), R 14 to R 16 The group is a hydrocarbon group having 1 to 20 carbon atoms, and may have unsaturated bonds, and may be the same or different.

[0427] R 17 , R 18 It is a hydrocarbon group having 1 to 20 carbon atoms that may be substituted with an organic group that does not have active hydrogen and includes Si, O, or N, and may have unsaturated bonds. e is an integer from 1 to 3.

[0428]

[0429] In Equation (16), R 31 to R 34 Each independently represents an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and R 35 represents an alkylene group having 1 to 10 carbon atoms, and R 36 It represents an alkylene group having 1 to 20 carbon atoms.

[0430] h represents an integer from 1 to 3, i represents an integer of 1 or 2, and (h+i) represents an integer greater than or equal to 4. R in the case where multiple exist 31 to R 34 Each is independent.

[0431]

[0432] In Equation (17), R 37 to R 42 Each independently represents an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and R 43 to R 45 Each independently represents an alkylene group having 1 to 20 carbon atoms.

[0433] m, n, and l each independently represent integers from 1 to 3, and (m+n+l) represents an integer greater than or equal to 4. R in the case where multiple exist 37 to R 42 Each is independent.

[0434]

[0435] In Equation (18), R 46 to R 48 Each independently represents a single bond or an alkylene group having 1 to 20 carbon atoms, and R 49 to R 52 Each independently represents an alkyl group having 1 to 20 carbon atoms, and R 53 and R 56 Each independently represents an alkylene group having 1 to 20 carbon atoms, and R 54 represents an alkylene group or an alkoxy group having 1 to 20 carbon atoms, and R 55 represents an alkyl group or a trialkylsilyl group having 1 to 20 carbon atoms.

[0436] o represents an integer from 1 to 3, and p represents 1 or 2.

[0437] R in the case where each exists in multiple instances 46 to R 56 , o and p are independent and may be the same or different.

[0438] q represents an integer from 0 to 6, r represents an integer from 0 to 6, s represents an integer from 0 to 6, and (q+r+s) is an integer from 4 to 10.

[0439] A represents an organic group having at least one atom selected from the group consisting of a hydrocarbon group having 1 to 20 carbon atoms, or an oxygen atom, a nitrogen atom, a silicon atom, a sulfur atom, and a phosphorus atom, and not having active hydrogen.

[0440] The coupling modifier represented by the above formula (14) is not limited to the following, but includes, for example, 1-methyl-4-(3-(trimethoxysilyl)propyl)piperazine, 1-methyl-4-(3-(triethoxysilyl)propyl)piperazine, 1-ethyl-4-(3-(trimethoxysilyl)propyl)piperazine, 1-ethyl-4-(3-(triethoxysilyl)propyl)piperazine, 1-propyl-4-(3-(trimethoxysilyl)propyl)piperazine, 1-propyl-4-(3-(triethoxysilyl)propyl)piperazine, 1-butyl-4-(3-(trimethoxysilyl)propyl)piperazine, 1-butyl-4-(3-(trimethoxysilyl)propyl)piperazine, Examples include 1-trimethylsilyl-4-(3-(trimethoxysilyl)propyl)piperazine, 1-trimethylsilyl-4-(3-(triethoxysilyl)propyl)piperazine, 1-triethylsilyl-4-(3-(trimethoxysilyl)propyl)piperazine, 1-triethylsilyl-4-(3-(triethoxysilyl)propyl)piperazine, 1-(t-butyldimethylsilyl)-4-(3-(trimethoxysilyl)propyl)piperazine, 1-(t-butyldimethylsilyl)-4-(3-(triethoxysilyl)propyl)piperazine, 1-triisopropylsilyl-4-(3-(trimethoxysilyl)propyl)piperazine, 1-triisopropylsilyl-4-(3-(triethoxysilyl)propyl)piperazine, etc.

[0441] Among these, from the perspective of increasing the reactivity and interaction between the conjugated diene polymer and inorganic fillers such as silica, and from the perspective of increasing processability, it is preferable that d in the above formula (14) be 3. Specifically, 1-methyl-4-(3-(trimethoxysilyl)propyl)piperazine and 1-methyl-4-(3-(triethoxysilyl)propyl)piperazine are preferred.

[0442] When reacting a coupling modifier having a group containing a nitrogen atom represented by the above formula (14) with a polymerization active end, the reaction temperature, reaction time, etc. are not particularly limited, but it is preferable to react at 0°C or higher and 120°C or lower for 30 seconds or more.

[0443] The amount of coupling modifier added as indicated by the above formula (14) is the alkoxy group (OR) bonded to the silyl group in the compound indicated by the above formula (14). 8 It is preferable that the total moles of the polymerization initiator be in a range of 0.2 times or more and 2.5 times or less, more preferable that they be in a range of 0.5 times or more and 2.0 times or less, and even more preferable that they be in a range of 1.0 times or more and 2.0 times or less. From the perspective of making the modification rate and molecular weight of the obtained conjugated diene polymer even more desirable, it is preferable to make it 0.2 times or more. In addition, from the perspective of suppressing the decrease in processability caused by an excessively high degree of branching, it is preferable to make it 2.5 times or less.

[0444] More specifically, the amount of polymerization initiator and the amount of coupling modifier represented by the formula (14) added can be adjusted so that the number of moles of the polymerization initiator is preferably 1.5 times or more, more preferably 1.7 times or more, relative to the number of moles of the coupling modifier represented by the formula (14).

[0445] The coupling modifier represented by the above formula (15) is not limited to the following, but includes, for example, N-(1,3-dimethylbutylidene)-3-(triethoxysilyl)-1-propanamine, N-(1,3-dimethylbutylidene)-3-(trimethoxysilyl)-1-propanamine, N-(1,3-dimethylbutylidene)-3-methyl(dimethoxysilyl)-1-propanamine, N-(1,3-dimethylbutylidene)-3-methyl(diethoxysilyl)-1-propanamine, N-(1-methylethylidene)-3-(triethoxysilyl)-1-propanamine, N-(1-methylethylidene)-3-(trimethoxysilyl)-1-propanamine, N-(1-methylethylidene)-3-methyl(dimethoxysilyl)-1-propanamine, N-(1-methylethylidene)-3-methyl(diethoxysilyl)-1-propanamine, N-ethylidene-3-(triethoxysilyl)-1-propanamine, N-ethylidene-3-(trimethoxysilyl)-1-propanamine, N-ethylidene-3-methyl(dimethoxysilyl)-1-propanamine, N-ethylidene-3-methyl(diethoxysilyl)-1-propanamine, N-(1-methylpropylidene)-3-(triethoxysilyl)-1-propanamine, N-(1-methylpropylidene)-3-(trimethoxysilyl)-1-propanamine, N-(1-methylpropylidene)-3-methyl(dimethoxysilyl)-1-propanamine, N-(1-methylpropylidene)-3-methyl(dimethoxysilyl)-1-propanamine, N-(1-methylpropylidene)-3-methyl(diethoxysilyl)-1-propanamine, N-Benzylidene-3-(Triethoxysilyl)Propan-1-amine, N-Benzylidene-3-(Triethoxysilyl)Propan-1-amine, N-Benzylidene-3-Methyl(Dimethoxysilyl)Propan-1-amine, N-Benzylidene-3-Methyl(Diethoxysilyl)Propan-1-amine, N-4-Methylbenzylidene-3-(Triethoxysilyl)Propan-1-amine, N-4-Methylbenzylidene-3-(Triethoxysilyl)Propan-1-amine, N-4-Methylbenzylidene-3-Methyl(Dimethoxysilyl)Propan-1-amine, N-4-Methylbenzylidene-3-Methyl(Diethoxysilyl)Propan-1-amine, N-Naphthylidene-3-(Triethoxysilyl)Propan-1-amine, N-Naphthylidene-3-(trimethoxysilyl)propan-1-amine, N-Naphthylidene-3-methyl(dimethoxysilyl)propan-1-amine, 1,1-(1,4-phenylene)bis(N-(3(triethoxysilyl)propyl)methaneamine), 1,1-(1,4-phenylene)bis(N-(3(trimethoxysilyl)propyl)methaneamine), 1,1-(1,4-phenylene)bis(N-(3methyl(dimethoxysilyl)propyl)methaneamine), 1,1-(1,4-phenylene)bis(N-(3methyl(diethoxysilyl)propyl)methaneamine), 2-methoxy-2-methyl-1-(benzylideneaminoethyl)-1-aza-2-silacyclopentane, 2-methoxy-2-methyl-1-(p-methoxybenzylideneaminoethyl)-1-aza-2-silacyclopentane, 2-ethoxy-2-methyl-1-(benzylideneaminoethyl)-1-aza-2-silacyclopentane, and 2-methoxy-2-methyl-1-(methylisobutylideneaminoethyl)-1-aza-2-silacyclopentane, etc. Can lift.

[0446] When reacting a coupling modifier having a group containing a nitrogen atom represented by the above formula (15) with a polymerization active end, the reaction temperature, reaction time, etc. are not particularly limited, but it is preferable to react at 0°C or higher and 120°C or lower for 30 seconds or more.

[0447] The amount of coupling modifier added as indicated by the above formula (15) is the alkoxy group (OR) bonded to the silyl group in the compound indicated by the above formula (15). 14 It is preferable that the total moles of the polymerization initiator be in a range of 0.2 times or more and 2.5 times or less, more preferable that they be in a range of 0.5 times or more and 2.0 times or less, and even more preferable that they be in a range of 1.0 times or more and 2.0 times or less. From the perspective of making the modification rate and molecular weight of the obtained conjugated diene polymer even more desirable, it is preferable to make it 0.2 times or more. In addition, from the perspective of suppressing the decrease in processability caused by an excessively high degree of branching, it is preferable to make it 2.5 times or less.

[0448] More specifically, the amount of polymerization initiator and the amount of coupling modifier represented by the formula (15) added can be adjusted so that the number of moles of the polymerization initiator is preferably 1.5 times or more, more preferably 1.7 times or more, with respect to the number of moles of the coupling modifier represented by the formula (15).

[0449] As a coupling modifier having a group containing a nitrogen atom represented by the above formula (16), examples 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, Examples include 2,2-diethoxy-1-(3-diethoxyethylsilylpropyl)-1-aza-2-silacyclopentane, 2-methoxy,2-methyl-1-(3-trimethoxysilylpropyl)-1-aza-2-silacyclopentane, 2-ethoxy,2-ethyl-1-(3-triethoxysilylpropyl)-1-aza-2-silacyclopentane, 2-methoxy,2-methyl-1-(3-dimethoxymethylsilylpropyl)-1-aza-2-silacyclopentane, and 2-ethoxy,2-ethyl-1-(3-diethoxyethylsilylpropyl)-1-aza-2-silacyclopentane.

[0450] Among these, in terms of the reactivity and interaction between the functional group of the coupling modifier having a group containing a nitrogen atom and an inorganic filler such as silica, and in terms of processability, it is preferable that i in the above formula (16) represents 2 and h represents 3. Specifically, 2,2-dimethoxy-1-(3-trimethoxysilylpropyl)-1-aza-2-silacyclopentane and 2,2-diethoxy-1-(3-triethoxysilylpropyl)-1-aza-2-silacyclopentane are preferred.

[0451] In the coupling process using the coupling modifier represented by the above formula (16), the reaction temperature and reaction time are not particularly limited, but preferably react at 0°C or higher and 120°C or lower, preferably for 30 seconds or more.

[0452] The amount of coupling modifier added as indicated by the above formula (16) is preferably in a range where the total moles of alkoxy groups bonded to the silyl groups in the compound indicated by the above formula (16) are 0.2 times or more and 2.5 times or less of the moles of polymerization initiator added, more preferably in a range where it is 0.5 times or more and 2.0 times or less, and even more preferably in a range where it is 1.0 times or more and 2.0 times or less. From the perspective of making the modification rate, molecular weight, and branching structure of the obtained conjugated diene polymer more desirable, it is preferable to make it 0.2 times or more. In addition, from the perspective of suppressing the decrease in processability caused by an excessively high degree of branching, it is preferable to make it 2.5 times or less.

[0453] More specifically, the amount of polymerization initiator and the amount of coupling modifier represented by the formula (16) added can be adjusted so that the number of moles of the polymerization initiator is preferably 3.0 times or more, more preferably 4.0 times or more, with respect to the number of moles of the coupling modifier represented by the formula (16).

[0454] Examples of modifying agents having a group containing a nitrogen atom represented by the above formula (17) are not limited to the following, but include 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.

[0455] Among these, it is preferable that n, m, and l in the above formula (17) all represent 3, in terms of the reactivity and interaction between the functional group of the modifying agent and inorganic fillers such as silica, and in terms of processability. Preferred specific examples include tris(3-trimethoxysilylpropyl)amine and tris(3-triethoxysilylpropyl)amine.

[0456] When reacting a modifying agent having a group containing a nitrogen atom represented by the above formula (17) with the polymerization active end, the reaction temperature, reaction time, etc. are not particularly limited, but it is preferable to react at 0°C or higher and 120°C or lower for 30 seconds or more.

[0457] It is preferable that the total number of moles of alkoxy groups bonded to silyl groups in the coupling modifier represented by the above formula (17) be in the range of 0.2 times or more and 2.0 times or less the number of moles of lithium constituting the polymerization initiator described above, more preferable that it be in the range of 0.5 times or more and 2.0 times or less, and even more preferable that it be in the range of 0.6 times or more and 1.6 times or less. In the case of a conjugated diene polymer, it is preferable to make it 0.2 times or more from the viewpoint of obtaining a sufficient modification rate, molecular weight, and branched structure, and in addition to the preference of coupling polymer ends together to obtain a branched polymer component for improved processability, it is preferable to make it 2.0 times or less from the viewpoint of the cost of the coupling modifier.

[0458] More specifically, the molar amount of the polymerization initiator is preferably 4.0 times the molar amount of the modifying agent, more preferably 5.0 times the molar amount.

[0459] In the above formula (18), A is preferably represented by any of the following general formulas (i) to (iv).

[0460]

[0461] Among the above equation (i), B 1represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, and t represents an integer from 1 to 10. B in the case where multiple exist. 1 Each is independent.

[0462]

[0463] Among the above equation (ii), B 2 represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, and B 3 represents an alkyl group having 1 to 20 carbon atoms, and t represents an integer from 1 to 10. B in the case where each exists in multiples. 2 and B 3 Each is independent.

[0464]

[0465] Among the above equation (iii), B 4 represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, and t represents an integer from 1 to 10. B in the case where multiple exist. 4 Each is independent.

[0466]

[0467] Among the above equation (iv), B 5 represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, and t represents an integer from 1 to 10. B in the case where multiple exist. 5 Each is independent.

[0468] In the above formula (18), the coupling modifier having a group containing a nitrogen atom when A is represented by the above formula (i) is not limited to the following, but includes, for example, tris(3-trimethoxysilylpropyl)amine, bis(3-trimethoxysilylpropyl)-[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]amine, bis[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]-(3-trimethoxysilylpropyl)amine, tris[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]amine, tris(3-ethoxysilylpropyl)amine, bis(3-triethoxysilylpropyl)-[3-(2,2-dimethoxy-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, Examples include tris[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]-(3-trimethoxysilylpropyl)-1,3-propanediamine.

[0469] Also, 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, Examples include 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, and tris(3-trimethoxysilylpropyl)-[3-(1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane)propyl]-1,3-bisaminomethylcyclohexane.

[0470] Also, bis(3-trimethoxysilylpropyl)-[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]-[3-(1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane)propyl]-1,3-bisaminomethylcyclohexane, bis[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]-(3-trimethoxysilylpropyl)-[3-(1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane)propyl]-1,3-bisaminomethylcyclohexane, Tris[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]-[3-(1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane)propyl]-1,3-bisaminomethylcyclohexane, tetrakis(3-triethoxysilylpropyl)-1,3-propanediamine, tris(3-triethoxysilylpropyl)-[3-(2,2-diethoxy-1-aza-2-silacyclopentane)propyl]-1,3-bisaminomethylcyclohexane, bis(3-triethoxysilylpropyl)-bis[3-(2,2-diethoxy-1-aza-2-silacyclopentane)propyl]-1,3-bisaminomethylcyclohexane, Tris[3-(2,2-diethoxy-1-aza-2-silacyclopentane)propyl]-(3-triethoxysilylpropyl)-1,3-propanediamine, tetrakis[3-(2,2-diethoxy-1-aza-2-silacyclopentane)propyl]-1,3-propanediamine, tris(3-triethoxysilylpropyl)-[3-(1-ethoxy-2-trimethylsilyl-1-sila-2-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-trimethoxysilylpropyl)-1,Examples include 6-hexamethylenediamine and pentakis(3-trimethoxysilylpropyl)-diethylenetriamine.

[0471] In the above formula (18), the coupling modifier having a group containing a nitrogen atom when A is represented by the above formula (ii) is not limited to the following, but includes, for example, tris(3-trimethoxysilylpropyl)-methyl-1,3-propanediamine, bis(2-trimethoxysilylpropyl)-[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]-methyl-1,3-propanediamine, bis[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]-(3-trimethoxysilylpropyl)-methyl-1,3-propanediamine, tris(3-triethoxysilylpropyl)-methyl-1,3-propanediamine, Bis(2-triethoxysilylpropyl)-[3-(2,2-diethoxy-1-aza-2-silacyclopentane)propyl]-methyl-1,3-propanediamine, bis[3-(2,2-diethoxy-1-aza-2-silacyclopentane)propyl]-(3-triethoxysilylpropyl)-methyl-1,3-propanediamine, N1,N1'-(propane-1,3-diyl)bis(N1-methyl-N3,N3-bis(3-(trimethoxysilyl)propyl)-1,3-propanediamine) and Examples include N1-(3-(bis(3-(trimethoxysilyl)propyl)amino)propyl)-N1-methyl-N3-(3-(methyl(3-(trimethoxysilyl)propyl)amino)propyl)-N3-(3-(trimethoxysilyl)propyl)-1,3-propanediamine.

[0472] In the above formula (18), the coupling modifier having a group containing a nitrogen atom when A is represented by the above formula (iii) is not limited to the following, but includes, for example, tetrakis[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]silane, tris[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]-(3-trimethoxysilylpropyl)silane, tris[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]-[3-(1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane)propyl]silane, bis(3-trimethoxysilylpropyl)-bis[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]silane, (3-trimethoxysilyl)-[3-(1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane)-bis[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]silane, bis[3-(1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane)-bis[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]silane, tris(3-trimethoxysilylpropyl)-[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]silane, Examples include 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.

[0473] In the above formula (18), when A is represented by formula (iv), the modifying agent having a group containing a nitrogen atom is not limited to the following, but examples include 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.

[0474] In the above formula (18), A is preferably represented by formula (i) or formula (ii), and s represents 0.

[0475] Coupling modifiers having groups containing such nitrogen atoms tend to be readily available, and also tend to have superior wear resistance and low hysteresis loss performance when conjugated diene polymers are vulcanized. As coupling modifiers having a group containing such a nitrogen atom, examples 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, Examples include tetrakis(3-trimethoxysilylpropyl)-1,3-bisaminomethylcyclohexane, tris(3-trimethoxysilylpropyl)-methyl-1,3-propanediamine, and bis[3-(2,2-dimethoxy-1-aza-2-silacyclopentane)propyl]-(3-trismethoxysilylpropyl)-methyl-1,3-propanediamine.

[0476] In the above formula (18), A is more preferably represented by formula (i) or formula (ii), s represents 0, and in formula (i) or formula (ii), t represents an integer from 2 to 10.

[0477] As a result, the wear resistance and low hysteresis loss performance tend to be superior when vulcanized.

[0478] As coupling modifiers having a group containing such a nitrogen atom, examples 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 Examples include -(3-(trimethoxysilyl)propyl)-1,3-propanediamine, etc.

[0479] The amount of compound represented by the above formula (18), which is a coupling modifier having a group containing a nitrogen atom, can be adjusted so that the number of moles of the polymerization initiator and the number of moles of the coupling modifier react in a desired stoichiometric ratio, and thereby a desired branched structure is tended to be achieved.

[0480] The specific molar amount of polymerization initiator is preferably 5.0 times or more, more preferably 6.0 times or more, with respect to the molar amount of coupling modifier.

[0481] In this case, in the above formula (18), the number of functional groups ((o-1)×q+p×r+s) of the coupling modifier is preferably an integer from 5 to 10, and more preferably an integer from 6 to 10.

[0482] The method for manufacturing conjugated diene polymers (A) and conjugated diene polymers (B) may include a condensation reaction process in which a condensation reaction is generated by adding a condensation promoter after the process of adding a coupling modifier and / or before the process of adding a coupling modifier.

[0483] The method for manufacturing conjugated diene polymers (A) and (B) may include a modification process using additional modifiers other than the coupling modifiers described above.

[0484] In the method for manufacturing conjugated diene polymer (A) and conjugated diene polymer (B), in the process of adding coupling modifiers, two types of coupling modifiers may be added, or three or more types may be added.

[0485] When adding two types of coupling modifiers, it is preferable to use a combination of coupling modifiers with different numbers of functional groups.

[0486] In addition, when adding three or more types of coupling modifiers, it is desirable to include a combination of coupling modifiers with different numbers of functional groups.

[0487] The method for manufacturing a conjugated diene polymer according to the present embodiment may include a hydrogenation process for hydrogenating the conjugated diene portion. The method for hydrogenating the conjugated diene portion is not particularly limited, and known methods may be used.

[0488] As a desirable hydrogenation process, a method of hydrogenating a conjugated diene by blowing gaseous hydrogen into a polymer solution in the presence of a catalyst can be cited.

[0489] The catalysts used are not particularly limited, but examples include heterogeneous catalysts such as a catalyst in which a precious metal is supported on a porous inorganic material; homogeneous catalysts such as a catalyst in which a salt of nickel, cobalt, etc. is solubilized and reacted with an organoaluminum, etc., and a catalyst using a metallocene such as titanocene.

[0490] Among these, titanocene catalysts are preferred from the perspective of being able to select milder hydrogenation conditions. Additionally, as a method for hydrogenating aromatic groups, a method using a precious metal-supported catalyst can be cited.

[0491] In addition, as a hydrogenation process that does not use gaseous hydrogen, a method of contacting a hydrogenation catalyst with a polymer solution can be cited. Such hydrogenation catalysts are not particularly limited, but examples include (1) a supported heterogeneous hydrogenation catalyst in which a metal such as Ni, Pt, Pd, or Ru is supported on carbon, silica, alumina, or diatomite, etc.; (2) a so-called Ziegler-type hydrogenation catalyst using a transition metal salt such as an organic acid salt or acetylacetone salt of Ni, Co, Fe, or Cr, and a reducing agent such as an organoaluminum, (3) a so-called organometallic complex such as an organometallic compound such as Ti, Ru, Rh, or Zr. In addition, other hydrogenation catalysts are not particularly limited, but include known hydrogenation catalysts described in, for example, Japanese Patent Publication No. Sho 42-8704, Japanese Patent Publication No. Sho 43-6636, Japanese Patent Publication No. Sho 63-4841, Japanese Patent Publication No. Hei 1-37970, Japanese Patent Publication No. Hei 1-53851, Japanese Patent Publication No. Hei 2-9041, and Japanese Patent Publication No. Hei 8-109219. Preferred hydrogenation catalysts include reaction mixtures of a titanocene compound and a reducing organometallic compound.

[0492] In the method for preparing a conjugated diene-based polymer of the present embodiment, a stabilizer, such as a deactivating agent and / or a neutralizing agent, may be added to the polymer solution as needed.

[0493] Examples of deactivating agents include, but are not limited to, water, and alcohols such as methanol, ethanol, and isopropanol.

[0494] Examples of neutralizing agents include, but are not limited to, carboxylic acids such as stearic acid, oleic acid, and versatic acid (a mixture of highly branched carboxylic acids with 9 to 11 carbon atoms and 10 carbon atoms as the main component), aqueous solutions of inorganic acids, and carbon dioxide.

[0495] As a stabilizer, it is desirable to add a rubber stabilizer from the perspective of preventing gel formation after polymerization and improving stability during processing.

[0496] As rubber stabilizers, known ones may be used, and are not limited to the following, but 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.

[0497] Mixing Process

[0498] In the method for manufacturing a conjugated diene polymer according to the present embodiment, as described above, a polymerization process and, if necessary, a modification process are performed to obtain a polymerization solution of a conjugated diene polymer (A) and a conjugated diene polymer (B), and then the solutions are mixed and the solvent is removed to obtain a conjugated diene polymer.

[0499] Regarding the mixing process, it is preferable to provide a storage tank for storing the polymerization solution discharged from each reaction tank downstream of the reaction tank for the conjugated diene polymer (A) and the reaction tank for the conjugated diene polymer (B). By providing a storage tank for each polymer, the flow rate can be adjusted before the mixing process, making it easier to fine-tune the mixing ratio of the polymer solution and allowing it to be stored in a tank different from the reaction tank.

[0500] It is more desirable for the capacity of the storage tank to be larger than that of the reaction tank.

[0501] As a mixing means, examples include using a tank equipped with a rotary stirrer or a pipe equipped with a rotary stirrer or a static mixer, although not limited to the following. From the perspective of mixing capacity, it is preferable to use a tank equipped with a rotary stirrer, and from the perspective of manufacturing efficiency, it is preferable to use a pipe equipped with a rotary stirrer or a static mixer.

[0502] The temperature in the mixing process is not particularly limited, but it is preferably 0°C or higher and 120°C or lower, and more preferably 50°C or higher and 100°C or lower. This is because a higher temperature lowers the viscosity of the polymerization solution, making it easier to mix. In a preferred embodiment, the solution discharged from the top of the head of the polymerization reactor is temporarily stored and then mixed. If the storage time is short and the temperature of the solution is maintained even after discharge from the polymerization reactor, there is no need for heating during the mixing process. However, if the storage time is long or the temperature of the solution is low, or if conditions are such that the temperature of the solution is prone to dropping, the storage tank, mixing tank, piping, etc. may be insulated or heated.

[0503] In the mixing process, the mixing mass ratio of the conjugated diene polymer (A) and the conjugated diene polymer (B) is preferably ((A) / (B)) = 10 / 90 to 40 / 60, more preferably 15 / 85 to 35 / 65, and even more preferably 20 / 80 to 30 / 70.

[0504] When in this range, bale forming ability is good, processability is excellent when vulcanized, and wear resistance is excellent when vulcanized.

[0505] In addition, the above-described ratio is the mass ratio of conjugated diene polymers. If the polymer solution of conjugated diene polymer (A) and the polymer solution of conjugated diene polymer (B) have the same concentration, they may be adopted as the mass ratio of the solutions. However, there are cases where the concentrations of these solutions differ. This is because, when manufacturing a polymer with a small molecular weight, the reaction heat tends to increase as the amount of polymerization initiator added increases, so the concentration of the solution may be lowered to maintain the polymerization temperature. In this case, it is desirable to adjust the mixing ratio to achieve a desirable mass ratio of polymers by taking into account the solution concentration.

[0506] The solvent removal process may use known methods such as drying and degassing. Examples of such methods include separating the solvent by steam stripping, etc., filtering and fractionating the polymer, and further dehydrating and drying the polymer to obtain the polymer, concentrating in a flushing tank and further degassing in a vent extruder, etc., or directly degassing in a drum dryer, etc.

[0507] (Rubber composition)

[0508] The rubber composition of the present embodiment contains a rubber component comprising the conjugated diene polymer of the present embodiment described above.

[0509] When the conjugated diene polymer of the present embodiment is incorporated into a tire, the oil content contained in the bale molded body is inevitably included in the tire. However, if the oil content is reduced, the oil content included in the tire is also reduced, so there is an advantage that the freedom of composition in the design of the tire is increased accordingly.

[0510] The conjugated diene polymer of the present embodiment and the sheet- or block-shaped molded body (also called a veil) thereof may have a softening agent component described below added to it. For the molded body (veil), from the perspective of improving the freedom of formulation design during the production of a rubber composition, it is preferable that the amount of rubber softening agent is 2 parts by mass or less per 100 parts by mass of the conjugated diene polymer, more preferable that it is 1.5 parts by mass or less, even more preferable that it is 1 part by mass or less, even more preferable that it is less than 1 part by mass, and most preferable that no softening agent be added, but the amount of rubber softening agent may be greater than 2 parts by mass.

[0511] As rubber softeners, examples include, but are not particularly limited, extension oil, liquid rubber, and resin.

[0512] It is desirable to provide a conjugated diene polymer and a sheet- or block-shaped molded body thereof without adding a rubber softener, in order to improve the freedom of formulation design when producing a rubber composition using said molded body.

[0513] Generally, there is an upper limit to the total amount of rubber softener in the entire rubber composition. However, when a rubber softener is added to a sheet- or block-shaped molded body of a conjugated diene polymer, the rubber composition produced by blending the molded body also contains the said rubber softener. Consequently, this limits the total amount of rubber softener in the entire rubber composition and restricts the freedom to select the type and amount of rubber softener that needs to be blended during the production of the rubber composition. From the perspective of improving the freedom to select the type and amount of rubber softener to match the performance desired in the rubber composition, it is desirable to reduce the amount of softener added to the sheet- or block-shaped molded body of a conjugated diene polymer.

[0514] Although not specifically limited, by reducing the amount of extensible oil added to, for example, the conjugated diene polymer of the present embodiment and the sheet- or block-shaped molded body thereof, it becomes possible to incorporate a larger amount of resin, such as extensible oil, when producing a rubber composition using them. This is desirable from the perspective of further improving the fracture strength of the rubber composition and its vulcanized product.

[0515] The rubber composition using the conjugated diene polymer of the present embodiment and the sheet- or block-shaped molded article thereof may further include a rubber stabilizer from the perspective of suppressing gel formation and improving stability during processing.

[0516] As rubber stabilizers, known ones may be used, not limited to the following, but examples include antioxidants such as 2,6-di-tert-butyl-4-hydroxytoluene (hereinafter also referred to as "BHT"), n-octadecyl-3-(4'-hydroxy-3',5'-di-tert-butylphenol)propionate, and 2-methyl-4,6-bis[(octylthio)methyl]phenol.

[0517] The rubber composition of the present embodiment comprises 100 parts by mass of a rubber component, comprising a conjugated diene polymer of the present embodiment, and 20 parts by mass or more and 150 parts by mass or less of a filler.

[0518] It is preferable that the above rubber component contains at least 10 parts by mass of the conjugated diene polymer of the present embodiment with respect to 100 parts by mass of the total amount of rubber components.

[0519] By dispersing a filler in a rubber component containing a conjugated diene polymer of the present embodiment, a rubber composition can be obtained that has even better processability when vulcanized and even better wear resistance of the vulcanized product.

[0520] Examples of fillers include, but are not limited to, silica-based inorganic fillers, carbon black, metal oxides, and metal hydroxides. Among these, silica-based inorganic fillers are preferred. In particular, when the rubber composition of the present embodiment is used for vulcanized rubber applications such as tires, anti-vibration rubber, automotive parts, or shoes, it is particularly preferable to include silica-based inorganic fillers. Such fillers may be used as a single type or in combination of two or more types.

[0521] As for the silica-based inorganic filler, there are no particular limitations and known materials may be used, but solid particles containing SiO2 or Si3Al as constituent units are preferred, and solid particles containing SiO2 or Si3Al as the main component of the constituent units are more preferred. Here, the main component refers to a component contained in the silica-based inorganic filler in an amount of more than 50 mass%, preferably 70 mass% or more, and more preferably 80 mass% or more.

[0522] Specific silica-based inorganic fillers are not limited to the following, but examples include inorganic fibrous materials such as silica, clay, talc, mica, diatomaceous earth, wollastonite, montmorillonite, zeolite, and glass fiber. Additionally, silica-based inorganic fillers with hydrophobic surfaces and mixtures of silica-based inorganic fillers and non-silica-based inorganic fillers may be used. Among these, silica or glass fiber is preferred, and silica is more preferred, from the perspective of further improving the strength and wear resistance of the rubber composition. As for silica, examples include dry silica, wet silica, and synthetic silicate silica, although not particularly limited. Among these silicas, wet silica is preferred from the perspective of further improving the fracture strength of the rubber composition.

[0523] From the perspective of more reliably obtaining a rubber composition having practically good wear resistance and fracture strength, the nitrogen adsorption specific surface area obtained by the BET adsorption method of a silica-based inorganic filler is preferably 100 m² / g or more and 300 m² / g or less, and more preferably 170 m² / g or more and 250 m² / g or less. Additionally, if necessary, a combination of a silica-based inorganic filler with a relatively small specific surface area (e.g., a specific surface area of ​​less than 200 m² / g) and a silica-based inorganic filler with a relatively large specific surface area (e.g., 200 m² / g or more) may be used. In the present embodiment, particularly when using a silica-based inorganic filler with a relatively large specific surface area (e.g., 200 m² / g or more), the conjugated diene polymer further improves the dispersibility of silica. As a result, the rubber composition obtained tends to have even better wear resistance, fracture strength, and low hysteresis loss.

[0524] Examples of carbon black include, but are not limited to, carbon black of each class such as SRF, FEF, HAF, ISAF, and SAF. Among these, carbon black having a nitrogen adsorption specific surface area of ​​50 m² / g or more as determined by the BET adsorption method and a dibutyl phthalate (DBP) absorption capacity of 80 mL / 100 g or less is preferred.

[0525] As a metal oxide, chemical formula M x O y (M represents a metal atom, and x and y each independently represent integers from 1 to 6.) The solid particles having as their main components are not particularly limited, but examples include alumina, titanium oxide, magnesium oxide, and zinc oxide.

[0526] Examples of metal hydroxides include, but are not limited to, aluminum hydroxide, magnesium hydroxide, and zirconium hydroxide.

[0527] The content of the silica-based inorganic filler in the rubber composition of the present embodiment is preferably 20 parts by mass or more and 150 parts by mass or less, 30 parts by mass or more and 130 parts by mass or less, with respect to 100 parts by mass of the rubber component, and more preferably 40 parts by mass or more and 110 parts by mass or less. By having the silica-based inorganic filler within the above range, the rubber composition has better processability when vulcanized, and the vulcanized product tends to have better low hysteresis loss, fracture characteristics, and wear resistance.

[0528] In the rubber composition of the present embodiment, from the viewpoint of reliably imparting performance required for applications such as tires, including dry grip performance and traction, it is preferable to include carbon black in an amount of 0.5 parts by mass or more and 100 parts by mass or less, per 100 parts by mass of a rubber component comprising a conjugated diene polymer. In the same viewpoint, the rubber composition includes carbon black in an amount of 3.0 parts by mass or more and 100 parts by mass or less, and even more preferably 5.0 parts by mass or more and 50 parts by mass or less, per 100 parts by mass of a rubber component comprising a conjugated diene polymer.

[0529] The rubber composition of the present embodiment may further include a silane coupling agent. By including a silane coupling agent in the rubber composition, the interaction between the rubber component and the filler can be further enhanced.

[0530] As a silane coupling agent, although not limited to the following, a compound having a sulfur bonding portion and an alkoxysilyl group or a silanol group portion in one molecule is preferred. Examples of such compounds, although not limited to the following, include bis-[3-(triethoxysilyl)-propyl]-tetrasulfide, bis-[3-(triethoxysilyl)-propyl]-disulfide, bis-[2-(triethoxysilyl)-ethyl]-tetrasulfide, etc.

[0531] In the rubber composition of the present embodiment, the content of the silane coupling agent is preferably 0.1 parts by mass or more and 30 parts by mass or less per 100 parts by mass of filler, more preferably 0.5 parts by mass or more and 20 parts by mass or less, and even more preferably 1.0 parts by mass or more and 15 parts by mass or less. When the content of the silane coupling agent is within the above range, there is a tendency to further improve the interaction between the rubber component and the filler.

[0532] The rubber composition of the present embodiment may include, as a rubber component, a rubbery polymer other than the conjugated diene polymer of the present embodiment (hereinafter simply referred to as "rubbery polymer"). Both the conjugated diene polymer of the present embodiment and the rubbery polymer are described as "rubber components."

[0533] Examples of rubbery polymers include, but are not limited to, conjugated diene polymers and their hydrogenated derivatives, random copolymers of conjugated diene compounds and vinyl aromatic compounds and their hydrogenated derivatives, block copolymers of conjugated diene compounds and vinyl aromatic compounds and their hydrogenated derivatives, non-diene polymers, natural rubber, etc.

[0534] Examples of rubbery polymers include, but not limited to the following, butane rubber and its hydrogenated derivatives, isoprene rubber and its hydrogenated derivatives, styrene-butadiene rubber and its hydrogenated derivatives, styrene-butadiene block copolymer and its hydrogenated derivatives, styrene-isoprene block copolymer and its hydrogenated derivatives, styrene-based elastomers, acrylonitrile-butadiene rubber and its hydrogenated derivatives, etc.

[0535] Examples of non-diene polymers include, but are not limited to the following, olefin 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, fluororubber, silicone rubber, chlorinated polyethylene rubber, epichlorohydrin rubber, α,β-unsaturated nitrile-acrylic acid ester-conjugated diene copolymer rubber, urethane rubber, polysulfide rubber, etc.

[0536] Examples of natural rubber include, but are not limited to, smoked sheets RSS3 to 5, SMR, epoxidized natural rubber, etc.

[0537] The rubbery polymer may be a modified rubber imparted with polar functional groups such as hydroxyl groups and amino groups. When the rubber composition of the present embodiment is used for tires, it is preferable that the rubbery polymer be one or more selected from the group consisting of butadiene rubber, isoprene rubber, styrene-butadiene rubber, natural rubber, and butyl rubber.

[0538] The weight-average molecular weight of the rubbery polymer is preferably 2,000 or more and 2,000,000 or less, and more preferably 5,000 or more and 1,500,000 or less, from the perspective of the balance between the wear resistance, fracture strength, low hysteresis loss, and processability of the rubber composition. In addition, as the rubbery polymer, a low molecular weight rubbery polymer, so-called liquid rubber, may be used. These rubbery polymers may be used as a single type or two or more types may be used in combination.

[0539] When the rubber composition of the present embodiment comprises a conjugated diene polymer and a rubbery polymer, the content ratio (mass ratio) of the conjugated diene polymer to the rubbery polymer is preferably 10 / 90 or more and 100 / 0 or less, more preferably 20 / 80 or more and 90 / 10 or less, and even more preferably 30 / 70 or more and 80 / 20 or less.

[0540] That is, the rubber component comprises, with respect to 100 parts by mass of the total amount of the rubber component, a conjugated diene polymer of the present embodiment, preferably 10 parts by mass or more and 100 parts by mass or less, more preferably 20 parts by mass or more and 90 parts by mass or less, and even more preferably 30 parts by mass or more and 80 parts by mass or less. When the proportion of the conjugated diene polymer included in the rubber component is within the above range, the processability when making a vulcanized product is further improved, and the wear resistance of the vulcanized product tends to be further improved.

[0541] The rubber composition of the present embodiment includes, in addition to the rubber component, a softening agent component (e.g., a rubber softener) to further improve its processability.

[0542] As for the softening agent components, they are not particularly limited, but examples include liquid rubber, resin, and extensible oil.

[0543] Liquid rubber is not particularly limited, but examples include liquid polybutadiene and liquid styrene-butadiene rubber.

[0544] When liquid rubber is used as a softening agent component, in addition to the above-mentioned effects, the glass transition temperature of the conjugated diene polymer composition can be further lowered, so the wear resistance, low hysteresis loss, and low-temperature properties of the vulcanized product tend to be further improved.

[0545] Examples of resins include, but are not limited to the following: aromatic petroleum resins, coumarone-indene resins, terpene resins, rosin derivatives (including tung oil resins), tall oil, tall oil derivatives, rosin ester resins, natural and synthetic terpene resins, aliphatic hydrocarbon resins, aromatic hydrocarbon resins, mixed aliphatic-aromatic hydrocarbon resins, coumarin-indene resins, phenol resins, p-tert-butylphenol-acetylene resins, phenol-formaldehyde resins, xylene-formaldehyde resins, monoolefin oligomers, diolefin oligomers, hydrogenated aromatic hydrocarbon resins, cyclic aliphatic hydrocarbon resins, hydrogenated hydrocarbon resins, hydrocarbon resins, hydrogenated tung oil resins, hydrogenated oil resins, esters of hydrogenated oil resins with monofunctional or polyfunctional alcohols, etc. These resins may be used as a single type or in combination of two or more types. In addition, when hydrogenating these resins, all unsaturated groups may be hydrogenated, or some may be left intact.

[0546] When a resin is used as a softening agent component, in addition to the above-mentioned effects, the fracture strength of the vulcanized product of the conjugated diene polymer composition tends to be further enhanced.

[0547] In the rubber composition of the present embodiment, it is suitable to add a resin as a softening agent component in addition to the rubber component in order to further improve the fracture strength of the vulcanized product.

[0548] In the rubber composition of the present embodiment, in order to further improve its processability, a softening agent component may be added in addition to the rubber component, but mineral oil or a liquid or low molecular weight synthetic softening agent is suitable.

[0549] Examples of new oils include aroma oils, naphthenic oils, and paraffin oils. Among these, from the perspective of environmental safety and from the perspective of preventing oil bleed and improving wet grip, an aroma substitute oil having a polycyclic aromatic (PCA) component of 3% or less according to the IP346 method is preferred. As for aroma substitute oils, examples include TDAE (Treated Distillate Aromatic Extracts), MES (Mild Extraction Solvate), and RAE (Residual Aromatic Extracts), as described in Kautschuk Gummi Kunststoffe 52 (12) 799 (1999).

[0550] Mineral oil-based rubber softeners, referred to as process oils or extender oils, used to promote the softening, expansion, and processing of rubber, are mixtures of aromatic rings, naphthenic rings, and paraffin chains. Among these, those in which the number of carbon atoms belonging to the paraffin chain is 50% or more of the total number of carbon atoms are called paraffinic, those in which the number of carbon atoms belonging to the naphthenic ring is 30% or more and 45% or less of the total number of carbon atoms are called naphthenic, and those in which the number of carbon atoms belonging to the aromatic ring exceeds 30% of the total number of carbon atoms are called aromatic. The rubber composition of the present embodiment preferably includes a rubber softener having a suitable aromatic content. By including such a rubber softener, the affinity with conjugated diene polymers is further improved.

[0551] The content of the softening agent component in the rubber composition of the present embodiment is expressed as the amount of the softening agent component previously added to the conjugated diene polymer of the present embodiment and the rubbery polymer described above, and the total amount of the softening agent component added when forming the rubber composition.

[0552] In the rubber composition of the present embodiment, the content of the softener component is preferably 0 parts by mass or more and 100 parts by mass or less with respect to 100 parts by mass of the rubber component, more preferably 10 parts by mass or more and 90 parts by mass or less, and even more preferably 30 parts by mass or more and 90 parts by mass or less. By having the content of the rubber softener component be 100 parts by mass or less with respect to 100 parts by mass of the rubber component, bleed-out can be suppressed and stickiness on the surface of the rubber composition can be further suppressed.

[0553] Regarding the method for manufacturing the rubber composition of the present embodiment, the method of mixing the conjugated diene polymer of the present embodiment, a rubbery polymer other than the conjugated diene polymer of the present embodiment, a filler, a silane coupling agent as needed, and a rubber softener, etc., is not particularly limited. Examples include a melt mixing method using a general mixer such as an open roll, a Banbury mixer, a kneader, a single-screw extruder, a twin-screw extruder, or a multi-screw extruder, and a method of heating and removing the solvent after melting and mixing each component. Among these, a melt mixing method using a roll, a Banbury mixer, a kneader, or an extruder is preferred from the perspective of productivity and good mixing performance. In addition, the rubber component, the filler, the silane coupling agent, and the additive may be mixed at once or divided into multiple stages.

[0554] The rubber composition of the present embodiment may be a vulcanized product that has undergone vulcanization treatment with a vulcanizing agent. Examples of vulcanizing agents include, but are not limited to the following: radical generating agents such as organic peroxides and azo compounds, oxime compounds, nitroso compounds, polyamine compounds, sulfur, and sulfur compounds. Sulfur compounds include sulfur monochloride, sulfur dichloride, disulfide compounds, polymeric polysulfide compounds, etc.

[0555] In the rubber composition of the present embodiment, the content of the vulcanizing agent is preferably 0.01 parts by mass or more and 20 parts by mass or less per 100 parts by mass of the rubber component, and more preferably 0.1 parts by mass or more and 15 parts by mass or less. As a vulcanization method, a conventionally known method may be used. In addition, as a vulcanization temperature, it is preferably 120°C or more and 200°C or less, and more preferably 140°C or more and 180°C or less.

[0556] When vulcanizing a rubber composition, vulcanization accelerators and / or vulcanization aids may be used as needed. As vulcanization accelerators, conventionally known materials may be used and are not limited to the following, but examples include sulfenamide-based, guanidine-based, thiuram-based, aldehyde-amine-based, aldehyde-ammonia-based, thiazole-based, thiourea-based, and dithiocarbamate-based vulcanization accelerators.

[0557] In addition, vulcanization aids include, but are not limited to, zinc oxide and stearic acid.

[0558] The content of the vulcanization accelerator and the vulcanization aid is preferably 0.01 parts by mass or more and 20 parts by mass or less, respectively, with respect to 100 parts by mass of the rubber component, and more preferably 0.1 parts by mass or more and 15 parts by mass or less.

[0559] In the rubber composition of the present embodiment, various additives other than those described above, such as softeners and fillers, heat stabilizers, antistatic agents, weather stabilizers, anti-aging agents, colorants, and lubricants, may be used to the extent that they do not impair the effects of the present embodiment. As a softener, known softeners may be used. As a filler, although not specifically limited, examples include calcium carbonate, magnesium carbonate, aluminum sulfate, and barium sulfate. As a heat stabilizer, antistatic agent, weather stabilizer, anti-aging agent, colorant, and lubricant, known materials may be used for each.

[0560] The rubber composition of the present embodiment is suitablely used as a rubber composition for tires.

[0561] Examples of tires according to the present embodiment include, but are not limited to, tires for agricultural machinery, tires for construction vehicles, tires for industrial vehicles, tires for trucks and buses, tires for light trucks, tires for passenger cars, etc. Additionally, examples of tires for passenger cars include various types such as fuel-efficient tires, all-season tires, high-performance tires, and studless tires, and the rubber composition according to the present embodiment can be suitably used in various parts of the tire, such as the tread, carcass, sidewall, and bead.

[0562] In addition, the rubber composition of the present embodiment has industrial applicability as, in addition to tires, anti-vibration rubber, anti-vibration rubber, conveyor belts, shoe soles such as outsoles for shoes, weatherstrips for automobiles, packing or gaskets, sealing materials, waterproof sheets, engine mounts, air springs, rubber gloves, medical hygiene products, hoses for industrial and various uses, battery cases, adhesives, wire insulation, window frame rubber, rubber plugs, rubber rollers, and materials for various industrial products.

[0563] In addition, the numerical range described above as a desirable range, etc., may be replaced with a numerical range formed by arbitrarily combining each value described as an upper limit and each value described as a lower limit, even in cases not specifically mentioned.

[0564] Examples

[0565] The present embodiment will be described in more detail below with reference to specific examples and comparative examples, but the present embodiment is not limited in any way by the following examples.

[0566] The materials used in the examples and comparative examples, and the methods for evaluating various characteristics are described below.

[0567] [Purification of 1,3-Butadiene]

[0568] 1,3-butadiene used in the polymerization of conjugated diene polymers was purified by the following process.

[0569] (Washing process)

[0570] It was operated under conditions of a circulation rate of 1 m³ / hr and a renewal (makeup) rate of 0.1 m³ / hr.

[0571] 1,3-butadiene and washing water were mixed using a static mixer (Static Mixer N60 Series manufactured by Noritake Company Limited), then transferred to a decanter, and the 1,3-butadiene phase and water phase were separated in the decanter.

[0572] In addition, it was operated under conditions of a liquid temperature of 30℃ and a decanter pressure of 1.0 MPaG.

[0573] The residence time of the 1,3-butadiene phase in the decanter was 30 minutes.

[0574] The aqueous phase separated by the above decanter was introduced into a de-1,3-butadiene solution, mixed with steam and heated to 89°C, and at the same time the total pressure was set to 0.01 MPaG to separate 1,3-butadiene from the aqueous phase.

[0575] (Oxygen removal process using a deoxidizer)

[0576] Next, a 10% aqueous solution of Diclin F-504 (manufactured by Kurita Kogyo) was used as a deoxidizer, and the 1,3-butadiene after the above (washing process) and the aqueous solution of the deoxidizer were mixed using a static mixer at a circulation flow rate of 1 m³ / hr, and liquid-liquid extraction was performed.

[0577] After that, it was moved to a decanter, and the 1,3-butadiene phase and the aqueous phase were separated in the decanter.

[0578] The residence time of the 1,3-butadiene phase in the decanter was 30 minutes. In addition, the operation was performed under conditions of a liquid temperature of 30°C and a decanter pressure of 1.0 MPaG.

[0579] (Polymerization Inhibitor Removal Process)

[0580] In addition, a 10% aqueous solution of caustic soda was mixed with the 1,3-butadiene obtained after the above (oxygen removal process by deoxidizer) using a packing tower containing poling at a circulation rate of 1 m³ / hr, liquid-liquid extraction was performed, the solution was transferred to another decanter, and the 1,3-butadiene phase and the aqueous phase were separated in the other decanter.

[0581] The residence time of the 1,3-butadiene phase in the other decanter was 60 minutes. In addition, the polymerization inhibitor removal process was operated under conditions of a liquid temperature of 30°C and a decanter pressure of 1.0 MPaG.

[0582] (Dehydration tower process)

[0583] In the above (polymerization inhibitor removal process), mixed hexane was added to the 1,3-butadiene separated into another decanter, and the 1,3-butadiene concentration was 50 mass% and supplied to a dehydration tower.

[0584] In a dehydration tower, the azeotropic mixture of 1,3-butadiene and water discharged from the top (top of the tower) was cooled and condensed, then transferred to a decanter, and the 1,3-butadiene phase and the aqueous phase were separated in the decanter.

[0585] The aqueous phase was removed, and the 1,3-butadiene phase was returned to the inlet of the dehydration tower, and the dehydration tower process was performed continuously.

[0586] A mixture of dehydrated 1,3-butadiene and hexane was extracted from the bottom of the dehydration tower.

[0587] (Adsorption process)

[0588] After the above (dehydration tower process), the mixture of 1,3-butadiene and hexane was passed through a 500L desiccant dryer containing activated alumina (vertical cylindrical tank manufactured by Hitachi Seisakusho Inc.) to adsorb and remove trace amounts of residual impurities in the 1,3-butadiene, and purified 1,3-butadiene was obtained.

[0589] [Purification of Styrene]

[0590] Styrene used for the polymerization of conjugated diene polymers was purified by the following process.

[0591] γ-alumina molded into a cylindrical shape of 3 mm φ × 3 mm was impregnated with an aqueous solution of palladium chloride at a concentration of 0.6% and dried at 100°C for one day and night. Next, the dried material was reduced under a hydrogen stream at a temperature of 400°C for 16 hours to obtain a hydrogenation catalyst with a composition of Pd(0.3%) / γ-Al2O3. 2000 g of the obtained hydrogenation catalyst was loaded into a tubular reactor, and purified styrene was obtained by circulating the catalyst for 8 hours while maintaining its temperature at 80°C.

[0592] [Purification of Normal Hexane]

[0593] Normal hexane used for the polymerization of conjugated diene polymers was purified by the following process.

[0594] Purified normal hexane was obtained by packing 2000g of molecular sieve 13-X (Union Showa) into a tubular reactor and circulating it at room temperature for 24 hours.

[0595] [(Physical Property 1) Amount of Binded Styrene]

[0596] A conjugated diene polymer was used as a sample, and 100 mg of the sample was diluted to 100 mL with chloroform and dissolved to be used as a measurement sample.

[0597] The amount of bound styrene (mass%) in 100 mass% of the sample conjugated diene polymer was measured by the amount of absorption of ultraviolet absorption wavelength (around 254 nm) by the phenyl group of styrene (spectrophotometer “UV-2450” manufactured by Shimadzu Seisakusho Co., Ltd.).

[0598] [(Physical Property 2) Microstructure of the butadiene moiety (amount of 1,2-vinyl bonds)]

[0599] A conjugated diene polymer was used as a sample, and 50 mg of the sample was dissolved in 10 mL of carbon disulfide to be used as a measurement sample.

[0600] Using a solution cell, the infrared spectrum from 600 to 1000 cm -1 The microstructure of the butadiene portion, i.e., the amount of 1,2-vinyl bonds (mol%), was determined by measuring within the range and using the absorbance at a given wavenumber according to the formula of Hampton's method (the method described in R-Hampton, Analytical Chemistry 21,923 (1949)) (Fourier transform infrared spectrophotometer "FT-IR230" manufactured by Nihon Bunko Co., Ltd.).

[0601] [(Physical Properties 3) Average Molecular Weight, Molecular Weight Distribution]

[0602] Using a conjugated diene polymer as a sample, a GPC measuring device (product name “HLC-8320GPC”) with three columns packed with polystyrene gel was used to measure the chromatogram using an RI detector (product name “HLC8020”), and based on the calibration curve obtained using standard polystyrene, the weight-average molecular weight (Mw), number-average molecular weight (Mn), and molecular weight distribution (Mw / Mn) were determined.

[0603] 0.4 wt% triethylamine-THF (tetrahydrofuran) was used as the eluent.

[0604] Three columns of the product name “TSKgel SuperMultiporeHZ-H” manufactured by Dososa Co. were connected, and a guard column of the product name “TSKguardcolumn SuperMP(HZ)-H” manufactured by Dososa Co. was connected and used in front of them.

[0605] 10 mg of the sample for measurement was dissolved in 10 mL of THF to make the measurement solution, and 10 μL of the measurement solution was injected into a GPC measuring device and measured under conditions of an oven temperature of 40°C and a THF flow rate of 0.35 mL / min.

[0606] [(Physical Property 4) Modification Rate Relative to Total Amount of Conjugated Diene Polymer]

[0607] A chromatogram was measured by using a conjugated diene polymer as a sample and applying the characteristic of adsorbing modified basic polymer components to a GPC column packed with silica gel.

[0608] The amount of adsorption to the silica column was measured from the difference between the chromatogram measured by the polystyrene-based column and the chromatogram measured by the silica-based column for the measurement sample solution containing the above measurement sample and low molecular weight internal standard polystyrene, and the modification rate was calculated.

[0609] Specifically, as shown below.

[0610] Preparation of sample solution for measurement:

[0611] 10 mg of the above measurement sample and 5 mg of standard polystyrene were dissolved in 10 mL of THF (tetrahydrofuran) to make the measurement sample solution.

[0612] GPC measurement conditions using a polystyrene-based column:

[0613] Using the Tosho Co. product name “HLC-8320GPC”, 10 μL of the sample solution for measurement was injected into the device using 0.4 wt% triethylamine-THF as the eluent, and a chromatogram was obtained using an RI detector under conditions of a column oven temperature of 40°C and a THF flow rate of 0.35 mL / min. Three columns of the Tosho Co. product name “TSKgel SuperMultiporeHZ-H” were connected, and the Tosho Co. product name “TSKguardcolumn SuperMP(HZ)-H” was connected as a guard column in front of them.

[0614] GPC measurement conditions using a silica-based column:

[0615] Using the product name “HLC-8320GPC” manufactured by Dosō Co., Ltd., 50 μL of a sample solution for measurement was injected into the device using THF as the eluent, and a chromatogram was obtained using an RI detector under conditions of a column oven temperature of 40°C and a THF flow rate of 0.5 mL / min. The columns used were connected with product names “Zorbax PSM-1000S”, “PSM-300S”, and “PSM-60S”, and a guard column with product name “DIOL 4.6×12.5㎜ 5micron” was connected upstream of them.

[0616] Method for calculating the modulation rate:

[0617] With the total peak area of ​​the chromatogram using a polystyrene-based column set to 100, the peak area of ​​the sample was set to P1 and the peak area of ​​the standard polystyrene was set to P2; with the total peak area of ​​the chromatogram using a silica-based column set to 100, the peak area of ​​the sample was set to P3 and the peak area of ​​the standard polystyrene was set to P4, and the modification rate (mass%) was calculated from the following formula.

[0618] Modification Rate (Mass%) = [1 - (P2 × P3) / (P1 × P4)] × 100

[0619] (In the above equation, P1+P2=P3+P4=100.)

[0620] [(Physical Property 5) Shape of molecular weight distribution curve, number of shoulders on the high molecular weight side compared to the peak top]

[0621] GPC measurements were performed using a conjugated diene polymer as a sample, a GPC measuring device (product name “HLC-8320GPC”) with two columns connected with polystyrene gel as a filler, and a refractive index (RI) detector (product name “HLC8020”).

[0622] A 2 wt% triethylamine-THF (tetrahydrofuran) solution was used as the eluent. Two columns of the product name “TSKgel GMHHR-H(S)” manufactured by Dosō Co., Ltd. were connected, and a guard column of the product name “TSKguardcolumn SuperMP(HZ)-H” manufactured by Dosō Co., Ltd. was connected to the front of them.

[0623] 10 mg of the sample for measurement was dissolved in 10 mL of THF to make the measurement solution, and 100 μL of the measurement solution was injected into a GPC measuring device and measured under conditions of an oven temperature of 40°C and a flow rate of 1.0 mL / min.

[0624] The shape of the molecular weight distribution curve obtained from the measurement results and the number of shoulders on the high molecular weight side relative to the peak top were confirmed.

[0625] [(Physical Property 6) Branching in the high molecular weight region]

[0626] Using a conjugated diene polymer as a sample, measurements were taken using a GPC measuring device (product name “GPCmax VE-2001”) with three columns connected with polystyrene gel as a filler, and three detectors connected in sequence, such as a light scattering detector, an RI detector, and a viscosity detector (product name “TDA305”), and based on standard polystyrene, the absolute molecular weight was obtained from the results of the light scattering detector and the RI detector, and the intrinsic viscosity was obtained from the results of the RI detector and the viscosity detector.

[0627] Linear polymers have an intrinsic viscosity [η0]=10 -3.534 M 0.712 Based on the above formula, the shrinkage factor (g') was calculated as the ratio of intrinsic viscosity corresponding to each molecular weight. In the above formula, M is the absolute molecular weight.

[0628] The eluent used was 5 mmol / L of triethylamine-containing THF.

[0629] The column used the product names "TSKgel G4000HXL", "TSKgel G5000HXL", and "TSKgel G6000HXL" from Dososa.

[0630] 20 mg of the sample for measurement was dissolved in 10 mL of THF to make the measurement solution, and 100 μL of the measurement solution was injected into a GPC measuring device and measured under conditions of an oven temperature of 40°C and a THF flow rate of 1 mL / min.

[0631] By the above measurements, the absolute molecular weight curve and branching distribution curve of the conjugated diene polymer are obtained, and the branching degree (Bn) is calculated using the shrinkage factor (g') as g'=6Bn / {(Bn+1)(Bn+2)}.

[0632] In the region on the high molecular weight side rather than the peak top of the above absolute molecular weight curve, when the absolute molecular weight at the first inflection point is Mw1 and the absolute molecular weight at the peak end point is Mw2, the branching degree (Bn) at the absolute molecular weight of (Mw1+Mw2) / 2 was calculated according to the above method of measuring the branching degree (Bn).

[0633] [(Physical Property 7) Oxidation Onset Temperature]

[0634] Using a conjugated diene polymer as a sample, the oxidation onset temperature was measured using a thermogravimetric analysis device (STA 7200R V, HITACHI). The oxidation onset temperature was determined by defining it as the temperature at which an endothermic peak was confirmed when the temperature was increased from 30°C to 500°C at a rate of 10°C / min under an atmospheric condition.

[0635] [(Physical Property 8) Shrinkage Factor in Peak Top Molecular Weight and Number Average Molecular Weight]

[0636] Using a conjugated diene polymer as a sample, measurements were taken using a GPC measuring device (product name “GPCmax VE-2001”) with three columns connected with polystyrene gel as a filler, and three detectors connected in sequence, such as a light scattering detector, an RI detector, and a viscosity detector (product name “TDA305”), and based on standard polystyrene, the absolute molecular weight was obtained from the results of the light scattering detector and the RI detector, and the intrinsic viscosity was obtained from the results of the RI detector and the viscosity detector.

[0637] Linear polymers have an intrinsic viscosity [η0]=10 -3.534 M 0.712 Based on the above formula, the shrinkage factor (g') was calculated as the ratio of intrinsic viscosity corresponding to each molecular weight. In the above formula, M is the absolute molecular weight.

[0638] The eluent used was 5 mmol / L of triethylamine-containing THF.

[0639] The column used the product names "TSKgel G4000HXL", "TSKgel G5000HXL", and "TSKgel G6000HXL" from Dososa.

[0640] 20 mg of the sample for measurement was dissolved in 10 mL of THF to make the measurement solution, and 100 μL of the measurement solution was injected into a GPC measuring device and measured under conditions of an oven temperature of 40°C and a THF flow rate of 1 mL / min.

[0641] The shrinkage factor (g') in the peak-top molecular weight (Mp) and number-average molecular weight (Mn) of the absolute molecular weight curve obtained by the above measurement was determined according to the above method for calculating the shrinkage factor (g').

[0642] [Preparation of Conjugated Diene Polymers]

[0643] (Conjugated diene polymer A1)

[0644] Two molding pressure vessels having a stirring device and a temperature control jacket, each having a volume of 10L and a ratio (L / D) of the internal height (L) to the diameter (D) of 4.0, an inlet at the bottom, and an outlet at the top, were connected to form a polymerization reactor.

[0645] 1,3-butadiene, with moisture removed beforehand, was mixed at a rate of 21.2 g / min, styrene at 7.1 g / min, and n-hexane at 208 g / min.

[0646] In addition, 2,2-bis(2-oxolanyl)propane as a polar substance at a rate of 0.0384 mmol / min and n-butyllithium (abbreviated as "NBL" in the table) as a polymerization initiator at a rate of 0.2742 mmol / min were supplied to the bottom of a polymerization reactor being vigorously mixed with a stirrer, and the polymerization reaction was continued continuously. The temperature was controlled so that the temperature of the polymer solution at the top outlet of the reactor was 85°C.

[0647] At the point when the polymerization was sufficiently stable, tetrakis(3-trimethoxysilylpropyl)-1,3-propanediamine (abbreviated as "A" in the table) was continuously added as a modifying agent at a rate of 0.0230 mmol / min to the polymer solution discharged from the outlet of the reactor, and the polymer solution with the added modifying agent was mixed by passing it through a static mixer and the modification reaction was carried out.

[0648] In the modified polymer solution, an antioxidant (BHT) was dissolved in hexane at a ratio of 0.2 g per 100 g of polymer and stearic acid at a ratio of 0.03 g per 100 g of polymer, respectively, and then added sequentially, and the polymerization reaction was terminated.

[0649] The solvent was removed from the conjugated diene polymer solution by steam stripping, and conjugated diene polymer A1 was obtained. Various measurements were performed, and the results are shown in Table 1.

[0650] In addition, the obtained polymer solution was transferred to a molding pressure vessel with a capacity of 100 L.

[0651] (Conjugated diene polymer A2)

[0652] Two molding pressure vessels having a stirring device and a temperature control jacket, each having a volume of 10L and a ratio (L / D) of the internal height (L) to the diameter (D) of 4.0, an inlet at the bottom, and an outlet at the top, were connected to form a polymerization reactor.

[0653] 1,3-butadiene, with moisture removed beforehand, was mixed at 21.2 g / min, styrene at 7.1 g / min, and n-hexane at 190 g / min.

[0654] In addition, 2,2-bis(2-oxolanyl)propane as a polar substance was supplied at a rate of 0.0307 mmol / min, and n-butyllithium (abbreviated as "NBL" in the table) as a polymerization initiator was supplied at a rate of 0.2123 mmol / min to the bottom of a polymerization reactor being vigorously mixed with a stirrer, and the polymerization reaction was continued continuously. The temperature was controlled so that the temperature of the polymer solution at the top outlet of the reactor was 85°C.

[0655] At the point when the polymerization was sufficiently stable, 2,2-dimethoxy-1-(3-(trimethoxysilyl)propyl)-1,2-azacilloridin (abbreviated as "B" in the table) was continuously added as a modifying agent at a rate of 0.0336 mmol / min to the polymer solution discharged from the outlet of the reactor, and the polymer solution with the added modifying agent was mixed by passing it through a static mixer and the modification reaction was carried out.

[0656] In the modified polymer solution, an antioxidant (BHT) was dissolved in hexane at a ratio of 0.2 g per 100 g of polymer and stearic acid at a ratio of 0.03 g per 100 g of polymer, respectively, and then added sequentially, and the polymerization reaction was terminated.

[0657] The solvent was removed from the conjugated diene polymer solution by steam stripping, and conjugated diene polymer A2 was obtained. Various measurements were performed, and the results are shown in Table 1.

[0658] In addition, the obtained polymer solution was transferred to a molding pressure vessel with a capacity of 100 L.

[0659] (Conjugated diene polymer A3)

[0660] Two molding pressure vessels having a stirring device and a temperature control jacket, each having a volume of 10L and a ratio (L / D) of the internal height (L) to the diameter (D) of 4.0, an inlet at the bottom, and an outlet at the top, were connected to form a polymerization reactor.

[0661] 1,3-butadiene, from which moisture had been removed beforehand, was mixed at a rate of 23.1 g / min, styrene at 7.7 g / min, and n-hexane at 206 g / min.

[0662] In addition, 2,2-bis(2-oxolanyl)propane as a polar substance was supplied at a rate of 0.0301 mmol / min, and n-butyllithium (abbreviated as "NBL" in the table) as a polymerization initiator was supplied at a rate of 0.1925 mmol / min to the bottom of a polymerization reactor being vigorously mixed with a stirrer, and the polymerization reaction was continued continuously. The temperature was controlled so that the temperature of the polymer solution at the top outlet of the reactor was 85°C.

[0663] At the point when the polymerization was sufficiently stable, trimethoxy(4-vinylphenyl)silane was supplied from the bottom of the first reactor as a branching agent at a rate of 0.0084 mmol / min, and trimethoxy(4-vinylphenyl)silane was supplied from the bottom of the second reactor as a branching agent at a rate of 0.0169 mmol / min to perform the polymerization branching process.

[0664] In the polymer solution discharged from the outlet of the reactor, an antioxidant (BHT) was dissolved in hexane at a ratio of 0.2 g per 100 g of polymer and stearic acid was dissolved at a ratio of 0.03 g per 100 g of polymer, respectively, and then added sequentially, and the polymerization reaction was terminated.

[0665] The solvent was removed from the conjugated diene polymer solution by steam stripping, and conjugated diene polymer A3 was obtained. Various measurements were performed, and the results are shown in Table 1.

[0666] In addition, the obtained polymer solution was transferred to a molding pressure vessel with a capacity of 100 L.

[0667] (Conjugated diene polymer A4)

[0668] Two molding pressure vessels having a stirring device and a temperature control jacket, each having a volume of 10L and a ratio (L / D) of the internal height (L) to the diameter (D) of 4.0, an inlet at the bottom, and an outlet at the top, were connected to form a polymerization reactor.

[0669] 1,3-butadiene, with moisture removed beforehand, was mixed at a rate of 21.2 g / min, styrene at 7.1 g / min, and n-hexane at 208 g / min.

[0670] In addition, 2,2-bis(2-oxolanyl)propane as a polar substance at a rate of 0.0384 mmol / min and n-butyllithium (abbreviated as "NBL" in the table) as a polymerization initiator at a rate of 0.2742 mmol / min were supplied to the bottom of a polymerization reactor being vigorously mixed with a stirrer, and the polymerization reaction was continued continuously. The temperature was controlled so that the temperature of the polymer solution at the top outlet of the reactor was 85°C.

[0671] At the point when the polymerization was sufficiently stable, tetrakis(3-trimethoxysilylpropyl)-1,3-propanediamine (abbreviated as "A" in the table) was continuously added as a modifying agent at a rate of 0.0287 mmol / min to the polymer solution discharged from the outlet of the reactor, and the polymer solution with the added modifying agent was mixed by passing it through a static mixer and the modification reaction was carried out.

[0672] In the modified polymer solution, an antioxidant (BHT) was dissolved in hexane at a ratio of 0.2 g per 100 g of polymer and stearic acid at a ratio of 0.03 g per 100 g of polymer, respectively, and then added sequentially, and the polymerization reaction was terminated.

[0673] The solvent was removed from the conjugated diene polymer solution by steam stripping, and the conjugated diene polymer A4 was obtained. Various measurements were performed, and the results are shown in Table 1.

[0674] In addition, the obtained polymer solution was transferred to a molding pressure vessel with a capacity of 100 L.

[0675] (Conjugated diene polymer A5)

[0676] Two molding pressure vessels having a stirring device and a temperature control jacket, each having a volume of 10L and a ratio (L / D) of the internal height (L) to the diameter (D) of 4.0, an inlet at the bottom, and an outlet at the top, were connected to form a polymerization reactor.

[0677] 1,3-butadiene, with moisture removed beforehand, was mixed at a rate of 21.2 g / min, styrene at 7.1 g / min, and n-hexane at 208 g / min.

[0678] In addition, 2,2-bis(2-oxolanyl)propane as a polar substance was supplied at a rate of 0.0184 mmol / min, and n-butyllithium (abbreviated as "NBL" in the table) as a polymerization initiator was supplied at a rate of 0.0885 mmol / min to the bottom of a polymerization reactor being vigorously mixed with a stirrer, and the polymerization reaction was continued continuously. The temperature was controlled so that the temperature of the polymer solution at the top outlet of the reactor was 90°C.

[0679] At the point when the polymerization was sufficiently stable, 2,2-dimethoxy-1-(3-(trimethoxysilyl)propyl)-1,2-azacilloridin (abbreviated as "B" in the table) was continuously added as a modifying agent at a rate of 0.0088 mmol / min to the polymer solution discharged from the outlet of the reactor, and the polymer solution with the added modifying agent was mixed by passing it through a static mixer and the modification reaction was carried out.

[0680] In the modified polymer solution, an antioxidant (BHT) was dissolved in hexane at a ratio of 0.2 g per 100 g of polymer and stearic acid at a ratio of 0.03 g per 100 g of polymer, respectively, and then added sequentially, and the polymerization reaction was terminated.

[0681] The solvent was removed from the conjugated diene polymer solution by steam stripping, and the conjugated diene polymer A5 was obtained. Various measurements were performed, and the results are shown in Table 1.

[0682] In addition, the obtained polymer solution was transferred to a molding pressure vessel with a capacity of 100 L.

[0683] (Conjugated diene polymer A6)

[0684] Two molding pressure vessels having a stirring device and a temperature control jacket, each having a volume of 10L and a ratio (L / D) of the internal height (L) to the diameter (D) of 4.0, an inlet at the bottom, and an outlet at the top, were connected to form a polymerization reactor.

[0685] 1,3-butadiene, from which moisture had been removed beforehand, was mixed at a rate of 23.1 g / min, styrene at 7.7 g / min, and n-hexane at 206 g / min.

[0686] In addition, 2,2-bis(2-oxolanyl)propane as a polar substance was supplied at a rate of 0.0301 mmol / min, and n-butyllithium (abbreviated as "NBL" in the table) as a polymerization initiator was supplied at a rate of 0.1925 mmol / min to the bottom of a polymerization reactor being vigorously mixed with a stirrer, and the polymerization reaction was continued continuously. The temperature was controlled so that the temperature of the polymer solution at the top outlet of the reactor was 85°C.

[0687] At the point when the polymerization was sufficiently stable, trimethoxy(4-vinylphenyl)silane was supplied from the bottom of the second reactor as a branching agent at a rate of 0.0108 mmol / min, and the polymerization branching process was carried out.

[0688] In the polymer solution discharged from the outlet of the reactor, an antioxidant (BHT) was dissolved in hexane at a ratio of 0.2 g per 100 g of polymer and stearic acid was dissolved at a ratio of 0.03 g per 100 g of polymer, respectively, and then added sequentially, and the polymerization reaction was terminated.

[0689] The solvent was removed from the conjugated diene polymer solution by steam stripping, and conjugated diene polymer A6 was obtained. Various measurements were performed, and the results are shown in Table 1.

[0690] In addition, the obtained polymer solution was transferred to a molding pressure vessel with a capacity of 100 L.

[0691] (Conjugated diene polymer A7)

[0692] Two molding pressure vessels having a stirring device and a temperature control jacket, each having a volume of 10L and a ratio (L / D) of the internal height (L) to the diameter (D) of 4.0, an inlet at the bottom, and an outlet at the top, were connected to form a polymerization reactor.

[0693] 1,3-butadiene, with moisture removed beforehand, was mixed at 21.2 g / min, styrene at 7.1 g / min, and n-hexane at 190 g / min.

[0694] In addition, 2,2-bis(2-oxolanyl)propane as a polar substance was supplied at a rate of 0.0430 mmol / min, and n-butyllithium (abbreviated as "NBL" in the table) as a polymerization initiator was supplied at a rate of 0.2742 mmol / min to the bottom of a polymerization reactor that was being vigorously mixed with a stirrer, and the polymerization reaction was continued continuously. The temperature was controlled so that the temperature of the polymer solution at the top outlet of the reactor was 85°C.

[0695] At the point when the polymerization was sufficiently stable, 2,2-dimethoxy-1-(3-(trimethoxysilyl)propyl)-1,2-azacilloridin (abbreviated as "B" in the table) was continuously added as a modifying agent at a rate of 0.0460 mmol / min to the polymer solution discharged from the outlet of the reactor, and the polymer solution with the added modifying agent was mixed by passing it through a static mixer and the modification reaction was carried out.

[0696] In the modified polymer solution, an antioxidant (BHT) was dissolved in hexane at a ratio of 0.2 g per 100 g of polymer and stearic acid at a ratio of 0.03 g per 100 g of polymer, respectively, and then added sequentially, and the polymerization reaction was terminated.

[0697] The solvent was removed from the conjugated diene polymer solution by steam stripping, and conjugated diene polymer A7 was obtained. Various measurements were performed, and the results are shown in Table 1.

[0698] In addition, the obtained polymer solution was transferred to a molding pressure vessel with a capacity of 100 L.

[0699] (Conjugated diene polymer A8)

[0700] Two molding pressure vessels having a stirring device and a temperature control jacket, each having a volume of 10L and a ratio (L / D) of the internal height (L) to the diameter (D) of 4.0, an inlet at the bottom, and an outlet at the top, were connected to form a polymerization reactor.

[0701] 1,3-butadiene, with moisture removed beforehand, was mixed at 21.2 g / min, styrene at 7.1 g / min, and n-hexane at 216 g / min.

[0702] In addition, 2,2-bis(2-oxolanyl)propane as a polar substance was supplied at a rate of 0.0174 mmol / min, and n-butyllithium (abbreviated as "NBL" in the table) as a polymerization initiator was supplied at a rate of 0.0833 mmol / min to the bottom of a polymerization reactor that was being vigorously mixed with a stirrer, and the polymerization reaction was continued continuously. The temperature was controlled so that the temperature of the polymer solution at the top outlet of the reactor was 90°C.

[0703] At the point when the polymerization was sufficiently stable, tetrakis(3-trimethoxysilylpropyl)-1,3-propanediamine (abbreviated as "A" in the table) was continuously added as a modifying agent at a rate of 0.0042 mmol / min to the polymer solution discharged from the outlet of the reactor, and the polymer solution with the added modifying agent was mixed by passing it through a static mixer and the modification reaction was carried out.

[0704] In the modified polymer solution, an antioxidant (BHT) was dissolved in hexane at a ratio of 0.2 g per 100 g of polymer and stearic acid at a ratio of 0.03 g per 100 g of polymer, respectively, and then added sequentially, and the polymerization reaction was terminated.

[0705] The solvent was removed from the conjugated diene polymer solution by steam stripping, and the conjugated diene polymer A8 was obtained. Various measurements were performed, and the results are shown in Table 1.

[0706] In addition, the obtained polymer solution was transferred to a molding pressure vessel with a capacity of 100 L.

[0707] (Conjugated diene polymer A9)

[0708] Two molding pressure vessels having a stirring device and a temperature control jacket, each having a volume of 10L and a ratio (L / D) of the internal height (L) to the diameter (D) of 4.0, an inlet at the bottom, and an outlet at the top, were connected to form a polymerization reactor.

[0709] 1,3-butadiene, from which moisture had been removed beforehand, was mixed at a rate of 23.1 g / min, styrene at 7.7 g / min, and n-hexane at 206 g / min.

[0710] In addition, 2,2-bis(2-oxolanyl)propane as a polar substance was supplied at a rate of 0.0402 mmol / min, and n-butyllithium (abbreviated as "NBL" in the table) as a polymerization initiator was supplied at a rate of 0.2888 mmol / min to the bottom of a polymerization reactor being vigorously mixed with a stirrer, and the polymerization reaction was continued continuously. The temperature was controlled so that the temperature of the polymer solution at the top outlet of the reactor was 85°C.

[0711] At the point when the polymerization was sufficiently stable, trimethoxy(4-vinylphenyl)silane was supplied from the bottom of the first reactor as a branching agent at a rate of 0.0270 mmol / min, and trimethoxy(4-vinylphenyl)silane was supplied from the bottom of the second reactor as a branching agent at a rate of 0.0271 mmol / min to perform the polymerization branching process.

[0712] In the polymer solution discharged from the outlet of the reactor, an antioxidant (BHT) was dissolved in hexane at a ratio of 0.2 g per 100 g of polymer and stearic acid was dissolved at a ratio of 0.03 g per 100 g of polymer, respectively, and then added sequentially, and the polymerization reaction was terminated.

[0713] The solvent was removed from the conjugated diene polymer solution by steam stripping, and conjugated diene polymer A9 was obtained. Various measurements were performed, and the results are shown in Table 1.

[0714] In addition, the obtained polymer solution was transferred to a molding pressure vessel with a capacity of 100 L.

[0715] (Conjugated diene polymer A10)

[0716] Two molding pressure vessels having a stirring device and a temperature control jacket, each having a volume of 10L and a ratio (L / D) of the internal height (L) to the diameter (D) of 4.0, an inlet at the bottom, and an outlet at the top, were connected to form a polymerization reactor.

[0717] 1,3-butadiene, with moisture removed beforehand, was mixed at a rate of 21.2 g / min, styrene at 7.1 g / min, and n-hexane at 208 g / min.

[0718] In addition, 2,2-bis(2-oxolanyl)propane as a polar substance was supplied at a rate of 0.0184 mmol / min, and n-butyllithium (abbreviated as "NBL" in the table) as a polymerization initiator was supplied at a rate of 0.0885 mmol / min to the bottom of a polymerization reactor being vigorously mixed with a stirrer, and the polymerization reaction was continued continuously. The temperature was controlled so that the temperature of the polymer solution at the top outlet of the reactor was 90°C.

[0719] In the polymer solution discharged from the outlet of the reactor, an antioxidant (BHT) was dissolved in hexane at a ratio of 0.2 g per 100 g of polymer and stearic acid was dissolved at a ratio of 0.03 g per 100 g of polymer, respectively, and then added sequentially, and the polymerization reaction was terminated.

[0720] The solvent was removed from the conjugated diene polymer solution by steam stripping, and the conjugated diene polymer A10 was obtained. Various measurements were performed, and the results are shown in Table 1.

[0721] In addition, the obtained polymer solution was transferred to a molding pressure vessel with a capacity of 100 L.

[0722] (Conjugated diene polymer A11)

[0723] Two molding pressure vessels having a stirring device and a temperature control jacket, each having a volume of 10L and a ratio (L / D) of the internal height (L) to the diameter (D) of 4.0, an inlet at the bottom, and an outlet at the top, were connected to form a polymerization reactor.

[0724] 1,3-butadiene, with moisture removed beforehand, was mixed at a rate of 21.2 g / min, styrene at 7.1 g / min, and n-hexane at 208 g / min.

[0725] In addition, 2,2-bis(2-oxolanyl)propane as a polar substance was supplied at a rate of 0.0184 mmol / min, and n-butyllithium (abbreviated as "NBL" in the table) as a polymerization initiator was supplied at a rate of 0.0885 mmol / min to the bottom of a polymerization reactor being vigorously mixed with a stirrer, and the polymerization reaction was continued continuously. The temperature was controlled so that the temperature of the polymer solution at the top outlet of the reactor was 90°C.

[0726] At the point when the polymerization was sufficiently stable, 2,2-dimethoxy-1-(3-(trimethoxysilyl)propyl)-1,2-azacilloridin (abbreviated as "B" in the table) was continuously added as a modifying agent at a rate of 0.0088 mmol / min to the polymer solution discharged from the outlet of the reactor, and the polymer solution with the added modifying agent was mixed by passing it through a static mixer and the modification reaction was carried out.

[0727] In the modified polymer solution, an antioxidant (BHT) was dissolved in hexane at a ratio of 0.2 g per 100 g of polymer and stearic acid at a ratio of 2.10 g per 100 g of polymer, respectively, and then added sequentially, and the polymerization reaction was terminated.

[0728] The solvent was removed from the conjugated diene polymer solution by steam stripping, and the conjugated diene polymer A11 was obtained. Various measurements were performed, and the results are shown in Table 1.

[0729] In addition, the obtained polymer solution was transferred to a molding pressure vessel with a capacity of 100 L.

[0730] (Conjugated diene polymer A12)

[0731] Two molding pressure vessels having a stirring device and a temperature control jacket, each having a volume of 10L and a ratio (L / D) of the internal height (L) to the diameter (D) of 4.0, an inlet at the bottom, and an outlet at the top, were connected to form a polymerization reactor.

[0732] 1,3-butadiene, with moisture removed beforehand, was mixed at 16.2 g / min, styrene at 10.0 g / min, and n-hexane at 196 g / min.

[0733] In addition, 2,2-bis(2-oxolanyl)propane as a polar substance was supplied at a rate of 0.0637 mmol / min, and n-butyllithium (abbreviated as "NBL" in the table) as a polymerization initiator was supplied at a rate of 0.1748 mmol / min to the bottom of a polymerization reactor being vigorously mixed with a stirrer, and the polymerization reaction was continued continuously. The temperature was controlled so that the temperature of the polymer solution at the top outlet of the reactor was 83°C.

[0734] At the point when the polymerization was sufficiently stable, trimethoxy(4-vinylphenyl)silane was supplied from the bottom of the second reactor as a branching agent at a condition of 0.0166 mmol / min to perform the polymerization branching process.

[0735] In the polymer solution discharged from the outlet of the reactor, an antioxidant (BHT) was dissolved in hexane at a ratio of 0.2 g per 100 g of polymer and stearic acid was dissolved at a ratio of 0.03 g per 100 g of polymer, respectively, and then added sequentially, and the polymerization reaction was terminated.

[0736] The solvent was removed from the conjugated diene polymer solution by steam stripping, and the conjugated diene polymer A12 was obtained. Various measurements were performed, and the results are shown in Table 1.

[0737] In addition, the obtained polymer solution was transferred to a molding pressure vessel with a capacity of 100 L.

[0738] (Conjugated diene polymer A13)

[0739] Two molding pressure vessels having a stirring device and a temperature control jacket, each having a volume of 10L and a ratio (L / D) of the internal height (L) to the diameter (D) of 4.0, an inlet at the bottom, and an outlet at the top, were connected to form a polymerization reactor.

[0740] 1,3-butadiene, with moisture removed beforehand, was mixed at 16.2 g / min, styrene at 10.0 g / min, and n-hexane at 196 g / min.

[0741] In addition, 2,2-bis(2-oxolanyl)propane as a polar substance was supplied at a rate of 0.0854 mmol / min, and n-butyllithium (abbreviated as "NBL" in the table) as a polymerization initiator was supplied at a rate of 0.2331 mmol / min to the bottom of a polymerization reactor being vigorously mixed with a stirrer, and the polymerization reaction was continued continuously. The temperature was controlled so that the temperature of the polymer solution at the top outlet of the reactor was 83°C.

[0742] At the point when the polymerization was sufficiently stable, trimethoxy(4-vinylphenyl)silane was supplied from the bottom of the second reactor as a branching agent at a condition of 0.0166 mmol / min to perform the polymerization branching process.

[0743] In the polymer solution discharged from the outlet of the reactor, an antioxidant (BHT) was dissolved in hexane at a ratio of 0.2 g per 100 g of polymer and stearic acid was dissolved at a ratio of 0.03 g per 100 g of polymer, respectively, and then added sequentially, and the polymerization reaction was terminated.

[0744] The solvent was removed from the conjugated diene polymer solution by steam stripping, and the conjugated diene polymer A13 was obtained. Various measurements were performed, and the results are shown in Table 1.

[0745] In addition, the obtained polymer solution was transferred to a molding pressure vessel with a capacity of 100 L.

[0746] (Conjugated diene polymer B1)

[0747] Two molding pressure vessels having a stirring device and a temperature control jacket, each having a volume of 10L and a ratio (L / D) of the internal height (L) to the diameter (D) of 4.0, an inlet at the bottom, and an outlet at the top, were connected to form a polymerization reactor.

[0748] 1,3-butadiene, with moisture removed beforehand, was mixed at 25.0 g / min, styrene at 8.3 g / min, and n-hexane at 205 g / min.

[0749] In addition, 2,2-bis(2-oxolanyl)propane as a polar substance was supplied at a rate of 0.0579 mmol / min, and n-butyllithium (abbreviated as "NBL" in the table) as a polymerization initiator was supplied at a rate of 0.4007 mmol / min to the bottom of a polymerization reactor that was being vigorously mixed with a stirrer, and the polymerization reaction was continued continuously. The temperature was controlled so that the temperature of the polymer solution at the top outlet of the reactor was 85°C.

[0750] In the polymer solution discharged from the outlet of the reactor, an antioxidant (BHT) was dissolved in hexane at a ratio of 0.2 g per 100 g of polymer and stearic acid was dissolved at a ratio of 0.03 g per 100 g of polymer, respectively, and then added sequentially, and the polymerization reaction was terminated.

[0751] The solvent was removed from the conjugated diene polymer solution by steam stripping, and conjugated diene polymer B1 was obtained. Various measurements were performed, and the results are shown in Table 1.

[0752] In addition, the obtained polymer solution was transferred to a molding pressure vessel with a capacity of 100 L.

[0753] (Conjugated diene polymer B2)

[0754] Two molding pressure vessels having a stirring device and a temperature control jacket, each having a volume of 10L and a ratio (L / D) of the internal height (L) to the diameter (D) of 4.0, an inlet at the bottom, and an outlet at the top, were connected to form a polymerization reactor.

[0755] 1,3-butadiene, with moisture removed beforehand, was mixed at 25.0 g / min, styrene at 8.3 g / min, and n-hexane at 205 g / min.

[0756] In addition, 2,2-bis(2-oxolanyl)propane as a polar substance was supplied at a rate of 0.0326 mmol / min, and n-butyllithium (abbreviated as "NBL" in the table) as a polymerization initiator was supplied at a rate of 0.2290 mmol / min to the bottom of a polymerization reactor being vigorously mixed with a stirrer, and the polymerization reaction was continued continuously. The temperature was controlled so that the temperature of the polymer solution at the top outlet of the reactor was 85°C.

[0757] In the polymer solution discharged from the outlet of the reactor, an antioxidant (BHT) was dissolved in hexane at a ratio of 0.2 g per 100 g of polymer and stearic acid was dissolved at a ratio of 0.03 g per 100 g of polymer, respectively, and then added sequentially, and the polymerization reaction was terminated.

[0758] The solvent was removed from the conjugated diene polymer solution by steam stripping, and conjugated diene polymer B2 was obtained. Various measurements were performed, and the results are shown in Table 1.

[0759] In addition, the obtained polymer solution was transferred to a molding pressure vessel with a capacity of 100 L.

[0760] (Conjugated diene polymer B3)

[0761] Two molding pressure vessels having a stirring device and a temperature control jacket, each having a volume of 10L and a ratio (L / D) of the internal height (L) to the diameter (D) of 4.0, an inlet at the bottom, and an outlet at the top, were connected to form a polymerization reactor.

[0762] 1,3-butadiene, with moisture removed beforehand, was mixed at 25.0 g / min, styrene at 8.3 g / min, and n-hexane at 205 g / min.

[0763] In addition, 2,2-bis(2-oxolanyl)propane as a polar substance was supplied at a rate of 0.0651 mmol / min, and n-butyllithium (abbreviated as "NBL" in the table) as a polymerization initiator was supplied at a rate of 0.4683 mmol / min to the bottom of a polymerization reactor being vigorously mixed with a stirrer, and the polymerization reaction was continued continuously. The temperature was controlled so that the temperature of the polymer solution at the top outlet of the reactor was 80°C.

[0764] In the polymer solution discharged from the outlet of the reactor, an antioxidant (BHT) was dissolved in hexane at a ratio of 0.2 g per 100 g of polymer and stearic acid was dissolved at a ratio of 0.03 g per 100 g of polymer, respectively, and then added sequentially, and the polymerization reaction was terminated.

[0765] The solvent was removed from the conjugated diene polymer solution by steam stripping, and conjugated diene polymer B3 was obtained. Various measurements were performed, and the results are shown in Table 1.

[0766] In addition, the obtained polymer solution was transferred to a molding pressure vessel with a capacity of 100 L.

[0767] (Conjugated diene polymer B4)

[0768] Two molding pressure vessels having a stirring device and a temperature control jacket, each having a volume of 10L and a ratio (L / D) of the internal height (L) to the diameter (D) of 4.0, an inlet at the bottom, and an outlet at the top, were connected to form a polymerization reactor.

[0769] 1,3-butadiene, with moisture removed beforehand, was mixed at 25.0 g / min, styrene at 8.3 g / min, and n-hexane at 205 g / min.

[0770] In addition, 2,2-bis(2-oxolanyl)propane as a polar substance was supplied at a rate of 0.0651 mmol / min, and n-butyllithium (abbreviated as "NBL" in the table) as a polymerization initiator was supplied at a rate of 0.4683 mmol / min to the bottom of a polymerization reactor being vigorously mixed with a stirrer, and the polymerization reaction was continued continuously. The temperature was controlled so that the temperature of the polymer solution at the top outlet of the reactor was 80°C.

[0771] At the point when the polymerization was sufficiently stable, 2,2-dimethoxy-1-(3-(trimethoxysilyl)propyl)-1,2-azacilloridin (abbreviated as "B" in the table) was continuously added as a modifying agent at a rate of 0.0520 mmol / min to the polymer solution discharged from the outlet of the reactor, and the polymer solution with the added modifying agent was mixed by passing it through a static mixer and the modification reaction was carried out.

[0772] In the modified polymer solution, an antioxidant (BHT) was dissolved in hexane at a ratio of 0.2 g per 100 g of polymer and stearic acid at a ratio of 0.03 g per 100 g of polymer, respectively, and then added sequentially, and the polymerization reaction was terminated.

[0773] The solvent was removed from the conjugated diene polymer solution by steam stripping, and conjugated diene polymer B4 was obtained. Various measurements were performed, and the results are shown in Table 1.

[0774] In addition, the obtained polymer solution was transferred to a molding pressure vessel with a capacity of 100 L.

[0775] (Conjugated diene polymer B5)

[0776] Two molding pressure vessels having a stirring device and a temperature control jacket, each having a volume of 10L and a ratio (L / D) of the internal height (L) to the diameter (D) of 4.0, an inlet at the bottom, and an outlet at the top, were connected to form a polymerization reactor.

[0777] 1,3-butadiene, with moisture removed beforehand, was mixed at a rate of 21.2 g / min, styrene at 7.1 g / min, and n-hexane at 208 g / min.

[0778] In addition, 2,2-bis(2-oxolanyl)propane as a polar substance was supplied at a rate of 0.0246 mmol / min, and n-butyllithium (abbreviated as "NBL" in the table) as a polymerization initiator was supplied at a rate of 0.1327 mmol / min to the bottom of a polymerization reactor being vigorously mixed with a stirrer, and the polymerization reaction was continued continuously. The temperature was controlled so that the temperature of the polymer solution at the top outlet of the reactor was 85°C.

[0779] In the polymer solution discharged from the outlet of the reactor, an antioxidant (BHT) was dissolved in hexane at a ratio of 0.2 g per 100 g of polymer and stearic acid was dissolved at a ratio of 0.03 g per 100 g of polymer, respectively, and then added sequentially, and the polymerization reaction was terminated.

[0780] The solvent was removed from the conjugated diene polymer solution by steam stripping, and conjugated diene polymer B5 was obtained. Various measurements were performed, and the results are shown in Table 1.

[0781] In addition, the obtained polymer solution was transferred to a molding pressure vessel with a capacity of 100 L.

[0782] (Conjugated diene polymer B6)

[0783] Two molding pressure vessels having a stirring device and a temperature control jacket, each having a volume of 10L and a ratio (L / D) of the internal height (L) to the diameter (D) of 4.0, an inlet at the bottom, and an outlet at the top, were connected to form a polymerization reactor.

[0784] 1,3-butadiene, with moisture removed beforehand, was mixed at 16.2 g / min, styrene at 10.0 g / min, and n-hexane at 196 g / min.

[0785] In addition, 2,2-bis(2-oxolanyl)propane as a polar substance was supplied at a rate of 0.0998 mmol / min, and n-butyllithium (abbreviated as "NBL" in the table) as a polymerization initiator was supplied at a rate of 0.2914 mmol / min to the bottom of a polymerization reactor being vigorously mixed with a stirrer, and the polymerization reaction was continued continuously. The temperature was controlled so that the temperature of the polymer solution at the top outlet of the reactor was 83°C.

[0786] In the polymer solution discharged from the outlet of the reactor, an antioxidant (BHT) was dissolved in hexane at a ratio of 0.2 g per 100 g of polymer and stearic acid was dissolved at a ratio of 0.03 g per 100 g of polymer, respectively, and then added sequentially, and the polymerization reaction was terminated.

[0787] The solvent was removed from the conjugated diene polymer solution by steam stripping, and conjugated diene polymer B6 was obtained. Various measurements were performed, and the results are shown in Table 1.

[0788] In addition, the obtained polymer solution was transferred to a molding pressure vessel with a capacity of 100 L.

[0789]

[0790] The following describes the modifying agent and branching agent.

[0791] A: Tetrakis(3-trimethoxysilylpropyl)-1,3-propanediamine

[0792] B: 2,2-Dimethoxy-1-(3-(trimethoxysilyl)propyl)-1,2-Azacilrolidine

[0793] Branching agent: Trimethoxy(4-vinylphenyl)silane

[0794] (Example 1: Conjugated diene polymer C1)

[0795] The polymer solutions of conjugated diene polymer A1 and conjugated diene polymer B1, prepared by the aforementioned method and transferred to a molding pressure vessel, were transferred such that the mass ratio of conjugated diene polymer A1 to conjugated diene polymer B1 was (A1):(B1) = 20:80, and combined within the piping. After combining, they were stirred and mixed using a rotary stirrer.

[0796] Next, the solvent was removed by steam stripping to obtain conjugated diene polymer C1.

[0797] Various measurements were performed, and the results are shown in Table 2.

[0798] (Examples 2 to 12: Conjugated diene polymers C2 to C12, Comparative Examples 1 to 8: Conjugated diene polymers C13 to C20, Comparative Example 9: ESBR1500)

[0799] The manufacturing method was the same as that for conjugated diene polymer C1, but the combination of conjugated diene polymer A and conjugated diene polymer B used was changed, and the content of conjugated diene polymer A in conjugated diene polymer C was changed as shown in Table 2 to obtain conjugated diene polymers C2 to C20. In addition, as Comparative Example 9, ESBR1500 manufactured by ENEOS Materials was used to obtain conjugated diene polymer C21.

[0800] Various measurements were performed, and the results are shown in Table 2.

[0801]

[0802] [Examples 13 to 24, Comparative Examples 10 to 18: Evaluation of veils of conjugated diene polymers C1 to C21]

[0803] (Appearance of the veil (presence or absence of cracks or breakage))

[0804] Regarding the veils of conjugated diene polymers shown in Table 2, their appearance, such as the presence or absence of external cracks or breakage, was visually observed and evaluated based on the following criteria. The appearance of the veil is an indicator of the veil moldability of the conjugated diene polymer. The evaluation results are shown in Table 3.

[0805] ○: No cracks, breakage, etc. are visible on the surface of the veil.

[0806] △: Cracks, breakage, etc. are visible on the surface of the veil.

[0807] ×: The crumbs do not clump together and cannot be formed into a veil.

[0808] [Examples 13 to 24, Comparative Examples 10 to 18]

[0809] Using the samples (conjugated diene polymers C1 to C21) shown in Table 2 above as raw rubber, a conjugated diene polymer composition containing each of the raw rubbers was obtained according to the formulations shown below.

[0810] · Sample: 100 parts by mass

[0811] · Silica (manufactured by Evonik Degussa, trade name "Ultrasil 7000GR", nitrogen adsorption specific surface area: 175 m² / g): 75 parts by mass

[0812] · Silane coupling agent (manufactured by Evonik Degussa, trade name "Si75" (tetraethoxysilylpropyldisulfide): 6 parts by mass

[0813] · Process oil (manufactured by JX Nikko Nisseki Energy, product name "NC140"): 42 parts by mass

[0814] · Carbon Black (Manufactured by Tokai Carbon, Product Name "Cyst KH (N339)", Iodine Adsorption Capacity 90 g / kg, CTAB Specific Surface Area 95 m² / g): 5 parts by mass

[0815] · Zinc oxide (Mitsui Kinzoku High School manufacturer, product name "Zinc Oxide No. 1"): 2.5 mass parts

[0816] · Stearic acid: 1.0 part by mass

[0817] · Wax: (Manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd., Trade name "Sanroku", yellowish-white granular, freezing point 65°C or higher, specific gravity 0.93): 1.5 parts by mass

[0818] · Anti-aging agent (N-isopropyl-N'-phenyl-p-phenylenediamine): 2.0 parts by mass

[0819] · Sulfur: 2.2 parts by mass

[0820] · Vulcanization accelerator (N-cyclohexyl-2-benzothiazylsulfinamide): 1.7 parts by mass

[0821] · Vulcanization accelerator (diphenylguanidine): 2.0 parts by mass

[0822] The above-mentioned materials were mixed by the following method to obtain an unvulcanized rubber composition and a vulcanized rubber sheet.

[0823] A kneader (capacity 0.5L) equipped with a temperature control device was used, and as a first stage of mixing, raw rubber (conjugated diene polymer C1 to C21), silica-based inorganic filler (silica), silane coupling agent, and process oil were mixed for 4 minutes under conditions of a filling rate of 65% and a rotor rotation speed of 30 to 50 rpm. At this time, the temperature of the kneader was controlled, and a conjugated diene polymer composition was obtained at a discharge temperature (mixture) of 155 to 160℃.

[0824] Next, as a second stage of mixing, the mixture obtained above was cooled to room temperature, carbon black, zinc oxide, stearic acid, wax, and an anti-aging agent were added, and the mixture was kneaded in the kneader for 3 minutes. In this case as well, the discharge temperature (of the mixture) was adjusted to 155 to 160°C by controlling the temperature of the mixer. Then, after discharging the mixture from the kneader, the mixture was passed through a 10-inch φ open roll 6 times to produce a sheet-shaped unvulcanized rubber composition, and after cooling, the processability was evaluated.

[0825] In addition, the unvulcanized composition was heated to 70°C for 30 minutes using an oven, and then, as a third stage of mixing, sulfur and a vulcanization accelerator were added and mixed using a 10-inch φ open roll set to 70°C to obtain the composition. Subsequently, the remainder of the composition was vulcanized using a vulcanization press at 160°C for 20 minutes to obtain a vulcanized product. After vulcanization, the physical properties of the rubber composition were measured. The results of the physical property measurements are shown in Table 3 below.

[0826] [Methods for Measuring Physical Properties]

[0827] (Mixture pattern viscosity)

[0828] After the second stage of mixing, the rubber composition was used as a sample, and the Mooney viscosity was measured using an L-type rotor in accordance with JIS K6300 using a Mooney viscometer (product name "VR1132" manufactured by Ueshima Seisakusho Co., Ltd.).

[0829] The measurement temperature was set to 100℃.

[0830] First, the sample is preheated at the test temperature for 1 minute, then the rotor is rotated at 2 rpm, and the torque is measured after 4 minutes to determine the Mooney viscosity (ML (1+4) ...did it as ).

[0831] The result of Comparative Example 10 was indexed to 100, and processability was evaluated according to the [Criteria for Evaluating Processability] below.

[0832] A higher index indicates better processability.

[0833] [Criteria for evaluating processability]

[0834] 5: The Mooney viscosity index of the mixture is 115 or higher.

[0835] 4: The Mooney viscosity index of the mixture is 105 or higher and less than 115.

[0836] 3: The Mooney viscosity index of the mixture is 95 or higher and less than 105.

[0837] 2: The Mooney viscosity index of the mixture is 85 or higher and less than 95.

[0838] 1: The Mooney viscosity index of the mixture is less than 85.

[0839] (hardness)

[0840] For the rubber composition after vulcanization, the hardness was measured at a temperature of 25°C using a Type A durometer in accordance with JIS K6253 (Shore-A measurement).

[0841] Based on the hardness value of Comparative Example 10, steering stability was evaluated according to the [Evaluation Criteria for Steering Stability] below.

[0842] A higher value indicates stiffness and good steering stability.

[0843] [Evaluation Criteria for Steering Stability]

[0844] 5: The hardness value of Comparative Example 10 is greater than 3.1.

[0845] 4: The hardness value is 2.1 to 3.0 greater than the hardness value of Comparative Example 10.

[0846] 3: The hardness value is ± 2.0 compared to the hardness value of Comparative Example 10.

[0847] 2: The hardness value is 2.1 to 3.0 smaller than the hardness value of Comparative Example 10.

[0848] 1: The hardness value of Comparative Example 10 is less than 3.1.

[0849] (Wear resistance)

[0850] For the rubber composition after vulcanization, an Akron wear tester (manufactured by Yasuda Seiki Seisakusho Co., Ltd.) was used, and the amount of wear was measured at a load of 44.4 N and 1,000 rotations in accordance with JIS K6264-2.

[0851] The result of Comparative Example 10 was indexed to 100, and the wear resistance was evaluated according to the [Wear Resistance Evaluation Criteria] below.

[0852] A higher index indicates better wear resistance.

[0853] [Evaluation Criteria for Wear Resistance]

[0854] 5: The wear index is 110 or higher.

[0855] 4: The wear index is 105 or higher and less than 110.

[0856] 3: The wear index is 95 or higher and less than 105.

[0857] 2: The wear index is 90 or higher and less than 95.

[0858] 1: The wear index is less than 90.

[0859] (Fuel efficiency)

[0860] Viscoelastic parameters were measured in torsional mode using the "ARES" viscoelastic testing machine manufactured by Rheometrics Scientific. The tanδ measured at 50°C with a frequency of 10 Hz and a deformation of 3% was used as an indicator of low hysteresis loss, i.e., fuel efficiency.

[0861] The result of Comparative Example 10 was indexed to 100, and the fuel efficiency was evaluated according to the [Evaluation Criteria for Fuel Efficiency Savings] below.

[0862] A higher index indicates better fuel efficiency.

[0863] [Evaluation Criteria for Fuel Efficiency]

[0864] 5: The fuel efficiency index is 115 or higher.

[0865] 4: The fuel efficiency index is 105 or higher and less than 115.

[0866] 3: The fuel efficiency index is 95 or higher and less than 105.

[0867] 2: The fuel efficiency index is 85 or higher and less than 95.

[0868] 1: The fuel efficiency index is less than 85.

[0869]

[0870] As shown in Table 3, the conjugated diene polymer of the present invention has good bale moldability, excellent processability when vulcanized, high hardness when vulcanized, and good wear resistance and fuel efficiency, so it can be seen that it has an excellent balance of performance. Industrial applicability

[0871] The conjugated diene polymer and rubber composition according to the present invention have industrial applicability in applications such as tires, resin modification, interior and exterior parts of automobiles, anti-vibration rubber, belts, shoes, foams, and various industrial products.

Claims

Claim 1 A conjugated diene polymer satisfying the following conditions (1) to (6). (1) The molecular weight distribution curve obtained by gel permeation chromatography (GPC) measurement is unimodal and has a shoulder in the region from the peak top of the molecular weight distribution curve to the peak endpoint on the high molecular weight side. (2) The weight-average molecular weight (Mw) measured by GPC is 200,000 to 1,000,000. (3) The molecular weight distribution is 1.7 to 3.

0. (4) The modification rate is less than 40 mass%. (5) In the region on the high molecular weight side from the peak top of the absolute molecular weight curve obtained by the GPC-light scattering measurement method equipped with a viscosity detector, when the absolute molecular weight at the first inflection point is Mw1 and the absolute molecular weight at the peak endpoint is Mw2, the degree of branching (Bn) at the absolute molecular weight of (Mw1+Mw2) / 2 is 4 or more. (6) The peak top obtained by the GPC-light scattering measurement method equipped with a viscosity detector The shrinkage factor (g') in the molecular weight (Mp) is 0.90 or higher. Claim 2 A conjugated diene polymer according to claim 1, wherein the shrinkage factor (g') in the number average molecular weight (Mn) obtained by the GPC-light scattering measurement method equipped with a viscosity detector is 0.90 or higher. Claim 3 A conjugated diene polymer according to claim 1, wherein the modification rate is less than 10 mass%. Claim 4 A conjugated diene polymer according to claim 1, comprising a conjugated diene polymer (A) having an Mw of 500,000 to 3,000,000 as measured by GPC, and a conjugated diene polymer (B) having an Mw of 100,000 to 500,000 as measured by GPC. Claim 5 A conjugated diene polymer according to claim 4, wherein the difference (ΔMw) of Mw between the conjugated diene polymer (A) and the conjugated diene polymer (B) is 200,000 or more. Claim 6 A conjugated diene polymer according to claim 4, wherein the mass ratio ((A) / (B)) of the conjugated diene polymer (A) and the conjugated diene polymer (B) is 10 / 90 to 40 / 60. Claim 7 A method for manufacturing a conjugated diene polymer as described in any one of claims 4 to 6, comprising: obtaining the conjugated diene polymer (A) and the conjugated diene polymer (B) by continuous polymerization using one or more reactors, mixing a polymer solution containing the conjugated diene polymer (A) and a polymer solution containing the conjugated diene polymer (B), and then performing solvent removal to obtain the conjugated diene polymer. Claim 8 A molded body comprising 100 parts by mass of a conjugated diene-based polymer described in any one of claims 1 to 6 and 2.0 parts by mass or less of an organic acid. Claim 9 A rubber composition comprising 100 parts by mass of a rubber component including a conjugated diene polymer described in any one of claims 1 to 6, and 20 parts by mass or more and 150 parts by mass or less of a filler.

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