JP2019065197A - Conjugated diene-based polymer composition, masterbatch, tire component, and method of producing conjugated diene-based polymer composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a rubber composition having excellent silica dispersibility, fuel saving performance, wet grip performance, practically sufficient breaking strength, breaking elongation and wear resistance, and a conjugated diene polymer. The composition is provided. SOLUTION: This is a conjugated diene-based polymer composition in which a silica-based inorganic filler is dispersed in a conjugated diene-based polymer, and the body integration rate of the silica-based inorganic filler in the conjugated diene-based polymer composition φ. A conjugated diene-based polymer composition in which (vol%) and the Pain effect ΔG'(MPa) calculated by the viscoelasticity test satisfy the following formula (1). ΔG'<0.250 × exp (0.162 × φ) ・ ・ ・ (I) (In the formula (I), ΔG'is 0.07 of the conjugated diene polymer composition in accordance with ASM D6204. It represents the Pain effect obtained as the difference between the% strain and the storage elastic modulus (G') value when measuring 1200% strain. Φ is the body integration rate of the silica-based inorganic filler in the conjugated diene-based polymer composition. (Vоl%).) [Selection diagram] None

Description

  The present invention relates to a conjugated diene polymer composition, a masterbatch, a tire component, and a method for producing a conjugated diene polymer composition.

In recent years, with the increasing demand for fuel efficiency improvement for automobiles, development of materials having low rolling resistance is required as a material for automobile tires, particularly tire treads in contact with the ground.
On the other hand, from the viewpoint of safety, when it is vulcanized while having excellent brake performance (wet skid resistance) on a wet road surface and good processability, reinforcement by a reinforcing filler There is a demand for a material having good wear resistance and fracture characteristics that is effective and sufficient for practical use.

  It is known that when silica is used as the reinforcing filler in place of carbon black which has been widely used in the past, a rubber composition excellent in the balance between rolling resistance and wet skid resistance can be obtained.

However, since the surface of silica has hydrophilicity, when the composition is combined with a highly hydrophobic conjugated diene-based polymer, the silica particles aggregate in the composition, and good dispersibility can not be obtained. Have the problem of
Therefore, by introducing (modifying) a functional group that interacts with the silica surface into the conjugated diene polymer, the affinity with the silica surface is enhanced, and the dispersibility of the silica in the composition is improved, and the rolling resistance is improved. Attempts have been made to make sex better.
For example, Patent Document 1 discloses a modified conjugated diene-based polymer obtained by reacting a modifier having a glycidyl amino group with a polymer terminal, and Patent Document 2 discloses an alkoxysilane containing a nitrogen atom. There is disclosed a modified conjugated diene-based polymer obtained by reacting a polymer with a polymer end.
Moreover, the method of improving the dispersibility of a silica is described in patent document 3 by adjusting the conditions of melt-kneading of resin and a silica.

WO 01/23467 pamphlet Japanese Patent Application Publication No. 2008-527150 JP 2008-266577 A

However, in the conventionally proposed conjugated diene-based polymer composition, a technology for realizing a higher performance tire in order to meet the increasing demand for further fuel saving and safety, and further wear resistance. Development is required.
Specifically, as described in Patent Document 1 or 2, although the dispersibility of the silica is improved by modifying the conjugated diene-based polymer so as to improve the affinity to the silica, such properties are exhibited. There is a problem that the structure of the polymer is limited, and the dispersibility of the silica regardless of the structure of the polymer (for example, even a non-modified or conjugated diene polymer having few functional groups) It is thought that if it is possible to increase the degree of freedom, the degree of freedom in designing the tire will be higher, which may also contribute to further improving safety and wear resistance, and the application will be extended to applications other than the tire. However, such technology has not been developed yet.
Moreover, since the method described in Patent Document 3 is a method of physically kneading a solid resin and silica although in a molten state, there is a problem that the improvement effect of the dispersibility is obtained only in a limited manner. doing.

  Therefore, in the present invention, in view of the problems of the prior art described above, the dependence on the structure of the conjugated diene polymer is small, the dispersibility of silica is improved, and the fuel saving performance and the wet grip performance are excellent. Provided are a conjugated diene-based polymer composition, a masterbatch, and a method for producing a conjugated diene-based polymer composition capable of obtaining a rubber composition having sufficient high breaking strength, breaking elongation and abrasion resistance. The purpose is

The inventors of the present invention conducted intensive studies to solve the problems of the prior art, and as a result, the volume fraction φ (vol%) of the silica-based inorganic filler and the Payne effect ΔG ′ of the conjugated diene-based polymer composition It has been found that the problems of the prior art can be solved by a conjugated diene polymer composition satisfying (MPa) and a predetermined relationship, and the present invention has been completed.
The present invention is as follows.

[1]
A conjugated diene-based polymer composition in which a silica-based inorganic filler is dispersed in a conjugated diene-based polymer,
A volume fraction φ (vol%) of the silica-based inorganic filler in the conjugated diene-based polymer composition,
Payne effect ΔG '(MPa) calculated by viscoelasticity test,
But,
The conjugated diene type polymer composition which satisfy | fills following formula (1).
ΔG ′ <0.250 × exp (0.162 × φ) (I)
(In the formula (I), ΔG ′ is the difference in storage elastic modulus (G ′) value when the 0.07% strain and the 1200% strain of the conjugated diene polymer composition are measured according to ASTM D 6204 Represents the Payne effect obtained as: φ represents the volume fraction (vol%) of the silica-based inorganic filler in the conjugated diene-based polymer composition.)
[2]
The conjugated diene polymer composition according to the above [1], further comprising 1 to 50 parts by mass, and further containing 1 to 50 parts by mass of a dispersant based on 100 parts by mass of the silica based inorganic filler.
[3]
The conjugated diene polymer composition according to the above [1] or [2], wherein the conjugated diene polymer is modified.
[4]
A masterbatch comprising the conjugated diene polymer composition according to any one of the above [1] to [3].
[5]
A tire member comprising the conjugated diene polymer composition according to any one of the above [1] to [3].
[6]
The method for producing a conjugated diene-based polymer composition according to any one of the above [1] to [3], wherein the silica-based inorganic filler is dispersed in a matrix of the conjugated diene-based polymer,
In the step (A), a silica-based inorganic filler is dispersed in a solution in which a conjugated diene-based polymer is dissolved to obtain a dispersion.
Desolvating the dispersion (C);
Have,
In the step (A), the silica-based inorganic filler is dispersed,
Method of producing a conjugated diene polymer composition.
[7]
The conjugated diene polymer composition according to the above [6], wherein 1 to 50 parts by mass of a dispersant is added to the solution with respect to 100 parts by mass of the silica based inorganic filler in the step (A) Manufacturing method.
[8]
As a process before the said process (A),
Manufacturing a conjugated diene polymer and modifying the conjugated diene polymer,
The manufacturing method of the conjugated diene type polymer composition as described in said [6] or [7].
[9]
In the step (C) of removing the solvent,
Heating the dispersion while conveying it to a device having a rotating twin screw,
The motor current value of the screw and the motor current value of the screw at no load condition satisfy the following formula (II):
The method for producing a conjugated diene polymer composition according to any one of the above [6] to [8].
1.05 ≦ ((I ₁ ) / (I ₀ )) ≦ 2.00 (II)
(In the formula (II), I ₁ represents the motor current value [A] of the screw in the step (C) of removing the solvent, and I ₀ represents the motor current value [A] of the screw at no load. Represent)
[10]
As a step prior to the step (C) of removing the solvent from the dispersion,
Carrying out the step (B) of adding a conjugated diene polymer solution or an oil,
The method for producing a conjugated diene polymer composition according to any one of the above [6] to [9].

  According to the present invention, it is possible to obtain a rubber composition having excellent silica dispersibility, excellent in fuel saving performance and wet grip performance, and having practically sufficient breaking strength, breaking elongation, and wear resistance. It is possible to provide a method for producing a conjugated diene polymer composition, a masterbatch, and a conjugated diene polymer composition.

  Hereinafter, modes for carrying out the present invention (hereinafter, referred to as “the present embodiment”) will be described in detail. The present embodiment below is an example for describing the present invention, and the present invention is not limited to the following embodiment. The present invention can be appropriately modified and implemented within the scope of the invention.

[Conjugated diene-based polymer composition]
The conjugated diene polymer composition of the present embodiment is
A conjugated diene-based polymer composition in which a silica-based inorganic filler is dispersed in a conjugated diene-based polymer,
A volume fraction φ (vol%) of the silica-based inorganic filler in the conjugated diene-based polymer composition,
Payne effect ΔG '(MPa) calculated by viscoelasticity test,
But,
It is a conjugated diene polymer composition which satisfies the following formula (1).
ΔG ′ <0.250 × exp (0.162 × φ) (I)
(In the formula (I), ΔG ′ is the difference in storage elastic modulus (G ′) value when the 0.07% strain and the 1200% strain of the conjugated diene polymer composition are measured according to ASTM D 6204 Represents the Payne effect obtained as: φ represents the volume fraction (vol%) of the silica-based inorganic filler in the conjugated diene-based polymer composition.)

(Conjugated diene polymer)
The conjugated diene polymer composition of the present embodiment contains a conjugated diene polymer.
The “conjugated diene-based polymer” is a polymer having at least one structure derived from conjugated diene in the repeating unit.
The conjugated diene polymer may be a homopolymer obtained by polymerizing a conjugated diene monomer.
The conjugated diene monomer is not particularly limited as long as it is a polymerizable monomer, and, for example, 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 3-Methyl-1,3-pentadiene, 1,3-heptadiene, and 1,3-hexadiene can be mentioned. Among these, 1,3-butadiene and isoprene are preferable from the viewpoint of industrial availability.
One of these may be used alone, or two or more may be used in combination.

The conjugated diene-based polymer may be a copolymer of the above-mentioned conjugated diene monomer and an aromatic vinyl monomer.
The aromatic vinyl monomer is not particularly limited as long as it is a monomer copolymerizable with the conjugated diene monomer, and examples thereof include styrene, m or p-methylstyrene, α-methylstyrene, vinylethylbenzene and vinyl These include xylene, vinyl naphthalene, diphenyl ethylene and divinyl benzene. Among these, styrene is preferable from the viewpoint of industrial availability. One of these may be used alone, or two or more may be used in combination.

In the method for producing a conjugated diene polymer composition of the present embodiment described later, the silica based inorganic filler is dispersed in a solution in which the conjugated diene based polymer is dissolved to obtain a conjugated diene based polymer and a silica based inorganic filler. And adding a dispersing agent in the step (A) of preparing the dispersion containing the compound, the conjugated diene polymer having high compatibility with the dispersing agent is preferable from the viewpoint of maximizing the surface activity effect of the dispersing agent. .
In addition, since the dispersant and the conjugated diene polymer are easily dissolved in the solvent used in the step (A), the dispersant is preferably reacted with the surface of the silica-based inorganic filler and the like. Furthermore, if the compatibility between the dispersant and the conjugated diene-based polymer is high after removing the solvent, the viscosity of the mixture of the silica-based inorganic filler can be lowered, and the processability is improved. preferable.
From the viewpoint described above, specifically, it is preferable to adopt a conjugated diene-based polymer having close solubility parameters.

When the conjugated diene-based polymer contains an aromatic vinyl monomer unit, the amount of the bound aromatic vinyl monomer (hereinafter, also simply referred to as “bound aromatic vinyl amount”) is the conjugated diene-based weight. The content is preferably 5.0% by mass or more and 70% by mass or less, and more preferably 10% by mass or more and 50% by mass or less based on the total amount (100% by mass) of the combination. When the conjugated diene-based polymer composition of this embodiment is processed into a tire such that the bound aromatic vinyl content is in such a range, the balance between the rolling resistance and the wet skid resistance of the tire tends to be more excellent. There is a tendency to be able to obtain a vulcanized conjugated diene polymer composition which is excellent in abrasion resistance and fracture strength.
Specifically, the amount of bound aromatic vinyl can be measured by ultraviolet absorption of a phenyl group, and the amount of bound conjugated diene can also be determined from this.

The amount of vinyl bond (1,2- or 3,4-bond) in the conjugated diene bond unit in the conjugated diene polymer is preferably 10 mol% or more and 75 mol% or less, and 13 mol% or more and 65 mol% It is more preferable that When the vinyl bond content is in the above range, the addition of a conjugated diene-based polymer composition is more excellent in the balance between low hysteresis loss and wet skid resistance when processed into a tire, and is also satisfactory in wear resistance and fracture strength. It tends to be able to obtain a vulcanizate.
When the conjugated diene polymer is a copolymer, the copolymer may be a random copolymer or a block copolymer. Here, when the conjugated diene polymer is a copolymer of butadiene and styrene, the vinyl in the butadiene bonding unit is obtained by the method of Hampton (R. R. Hampton, Analytical Chemistry, 21, 923 (1949)). The binding amount (1,2-binding amount) can be determined.
The random copolymer includes, but is not limited to, for example, butadiene-isoprene random copolymer, butadiene-styrene random copolymer, isoprene-styrene random copolymer, and butadiene-isoprene-styrene random copolymer It can be mentioned.
The compositional distribution of each monomer in the copolymer chain includes a completely random copolymer close to a statistically random composition, and a tapered (gradient) random copolymer having a gradient in the compositional distribution. The bonding mode of the conjugated diene-based polymer, that is, the composition of 1,4-linkage, 1,2-bond, etc. may be uniform or different depending on the molecular chain.

Examples of block copolymers include, but are not limited to, for example, 2 type block copolymers consisting of 2 blocks, 3 type block copolymers consisting of 3 blocks, and 4 type block copolymers consisting of 4 blocks It can be mentioned. Here, a block consisting of an aromatic vinyl monomer such as styrene is represented by S, and a block consisting of a conjugated diene monomer such as butadiene and isoprene and / or a mixture of an aromatic vinyl monomer and a conjugated diene monomer When a block consisting of a copolymer is represented by B, it is represented by a formula such as S2-B type block copolymer, S-B-S3 type block copolymer, and S-B-S-B type 4 block copolymer. Be done.
In the above equation, the boundaries of each block do not necessarily have to be clearly distinguished. For example, when block B is a copolymer of an aromatic vinyl monomer and a conjugated diene monomer, the aromatic vinyl monomer in block B may be uniformly distributed or tapered. It may be Further, in the block B, a plurality of portions in which the aromatic vinyl monomer is uniformly distributed and / or a portion in which the aromatic vinyl monomer is distributed in a tapered shape may coexist respectively. Furthermore, in the block B, a plurality of segments having different aromatic vinyl monomer content may coexist. When two or more blocks S and blocks B are present in the copolymer, the structures of their molecular weight and composition may be the same or different.

The size of the molecular weight of the conjugated diene polymer has little direct influence on the dispersibility of the silica based inorganic filler, but when the conjugated diene polymer composition of the present embodiment is used for a tire, the conjugated diene based polymer The weight average molecular weight (Mw) of the polymer is preferably 100,000 or more and 2,000,000 or less from the viewpoint of processability and physical properties. Further, it is more preferably 150,000 or more, still more preferably 200,000 or more, and still more preferably 250,000 or more. The weight average molecular weight is more preferably 1.8 million or less, further preferably 1.5 million or less, and still more preferably 1.3 million or less.
In general, the molecular weight of the conjugated diene polymer may indirectly affect the dispersibility of the silica-based inorganic filler. That is, when the molecular weight is high, the viscosity of the conjugated diene polymer is high, and therefore, when it is attempted to melt and knead it is difficult to mix with the silica inorganic filler, and the dispersibility of the silica inorganic filler tends to be low In the case of the form, as shown in the method for producing a conjugated diene-based polymer composition described later, in the step (A), a silica-based inorganic filler is mixed with a solution in which the conjugated diene-based polymer is dissolved, The influence of difficulty in melt-kneading for dispersion is small. It is also possible to lower the viscosity by adding an oil to lower the viscosity of the mixture or lowering the solid content concentration.

The molecular weight distribution (Mw / Mn) (Mn: number average molecular weight, Mw: weight average molecular weight) of the conjugated diene polymer is preferably 1.02 or more and 6.0 or less, and 1.05 or more and 5.0 or less Is more preferably 1.07 or more and 4.0 or less. When the molecular weight distribution is 6.0 or less, low hysteresis loss tends to be favorable. In addition, when the molecular weight distribution is 1.02 or more, the mixability and the processability of the silica-based inorganic filler tend to be good. In addition, in the method for producing a conjugated diene polymer composition of the present embodiment described later, from the viewpoint of the operability in the step (C) of removing the solvent from the solution of the conjugated diene polymer in which the silica based inorganic filler is dispersed, As for (Mw / Mn), 1.5 or more and 3.0 or less are more preferable, and 1.7 or more and 2.7 or less are more preferable.
The weight average molecular weight and the number average molecular weight can be determined from gel permeation chromatography (hereinafter referred to as "GPC") as a calibration equation using a standard polystyrene sample.

  From the viewpoint of the abrasion resistance and strength of the conjugated diene polymer composition of the present embodiment and the molded article thereof, the conjugated diene polymer has a molecular weight relative to the total amount (100% by mass) of the conjugated diene polymer The content of components of 1,000,000 or more is preferably 1.0% by mass to 99% by mass, more preferably 5.0% by mass to 70% by mass, and 10% by mass to 50% by mass It is further preferred that The component having a molecular weight of 1,000,000 or more in the conjugated diene-based polymer can be measured by GPC as a calibration equation using a standard polystyrene sample as described above.

  The Mooney viscosity of the conjugated diene polymer is preferably 20 or more and 120 or less, more preferably 30 or more and 110 or less, and still more preferably 40 or more and 100 or less. When the Mooney viscosity is 120 or less, the mixability of the silica-based inorganic filler and the processability of the conjugated diene-based polymer composition of the present embodiment tend to be good. Further, when the Mooney viscosity is 20 or more, the vulcanized physical properties tend to be good. Mooney viscosity can be measured by the method based on JISK6300-1: 2001, and can specifically be measured by the method described in the Example mentioned later.

(Method for producing conjugated diene polymer)
The method for producing the conjugated diene-based polymer is not particularly limited, but an emulsion polymerization method, a solution polymerization method, etc. may be mentioned, but a solution polymerization method is preferable in terms of operation control, molecular structure control, and ease of molecular modification (modification). .
A known method can be applied to a method for producing a conjugated diene polymer using a solution polymerization method. Generally, in a hydrocarbon solvent, an alkali metal compound or an alkaline earth metal compound is used as a polymerization initiator to polymerize a conjugated diene monomer or a conjugated diene monomer and an aromatic vinyl monomer Alternatively, a polymerization step for obtaining a conjugated diene polymer having an active end, a modification step of reacting with a modifier if necessary, and further volatilizing a hydrocarbon solvent to obtain a solid content (a conjugated diene polymer) It can be produced by a process comprising an isolated degassing step.

<Solvent for polymerization reaction>
The polymerization reaction in the polymerization step of the conjugated diene-based polymer using the solution polymerization method is preferably a reaction of solution polymerization in which polymerization is performed in a solvent (hereinafter, also referred to as “solvent for polymerization reaction”).
Examples of the polymerization reaction solvent include, but are not limited to, hydrocarbon solvents such as saturated hydrocarbons and aromatic hydrocarbons.
Specific solvents for polymerization reaction include aliphatic hydrocarbons such as butane, pentane, hexane and heptane; alicyclic hydrocarbons such as cyclopentane, cyclohexane, methylcyclopentane and methylcyclohexane; benzene, toluene, xylene and the like Aromatic hydrocarbons; hydrocarbons comprising a mixture of these, and the like can be mentioned.

<Polymerization initiator>
Although the alkali metal compound used as a polymerization initiator in the superposition | polymerization process of the conjugated diene type polymer which used the solution polymerization method is not specifically limited, An organic lithium compound is preferable.
Examples of the organic lithium compound include low molecular weight compounds, organic lithium compounds of solubilized oligomers, compounds having a carbon-lithium bond in the bonding mode of an organic group and lithium, and compounds having a tin-lithium bond.
Examples of the organic lithium compound include, but are not limited to, n-butyllithium, sec-butyllithium, tert-butyllithium, n-hexyllithium, benzyllithium, phenyllithium, stilbenelithium and the like. .
In addition to the above mono-organolithium compounds, polymerization can also be carried out using a combination of polyfunctional organo-lithium compounds.
Examples of the polyfunctional organic lithium compound include, but are not limited to, 1,4-dilithiobutane, a reaction product of sec-butyllithium and diisopropenylbenzene, 1,3,5-trilithiobenzene, The reaction product of n-butyllithium and 1,3-butadiene and divinylbenzene, the reaction product of n-butyllithium and polyacetylene compound, and the like can be mentioned. Furthermore, known organic alkali metal compounds disclosed in U.S. Patent No. 5,708,092, British Patent No. 2,241,239, U.S. Patent No. 5,527,753, etc. It can be used.
As the organolithium compound, n-butyllithium and sec-butyllithium are preferable from the viewpoint of industrial availability and easiness of control of polymerization reaction.
One of these organic lithium compounds may be used alone, or two or more thereof may be used in combination.
As another organic alkali metal compound, an organic sodium compound, an organic potassium compound, an organic rubidium compound, an organic cesium compound etc. are mentioned, for example. Specifically, sodium naphthalene, potassium naphthalene and the like can be mentioned. In addition, alkoxides such as lithium, sodium and potassium, sulfonates, carbonates and the like can be mentioned. Moreover, you may use together with another organometallic compound.
Examples of alkaline earth metal compounds include organic magnesium compounds, organic calcium compounds, organic strontium compounds and the like. Also, compounds such as alkali earth metal alkoxides, sulfonates and carbonates may be used. These organic alkaline earth metal compounds may be used in combination with alkali metal compounds and other organic metal compounds.

<Polymerization form>
The polymerization mode of the conjugated diene polymer using the solution polymerization method is not particularly limited, but it can be carried out in a batch mode (also referred to as a "batch type"), a continuous mode or the like. In the continuous mode, one or more linked reactors can be used. As a reactor, a tank type with a stirrer, a tube type, or the like is used.

(Modified conjugated diene-based polymer)
The conjugated diene-based polymer contained in the conjugated diene-based polymer composition of the present embodiment may be one modified in the production process (in which a functional group is introduced), or it may be non-modified. It may be.
A non-modified conjugated diene polymer is also obtained by dispersing a silica based inorganic filler in a solution in which a conjugated diene polymer is dissolved in the method for producing a conjugated diene polymer composition of the present embodiment described later. In step (A), by using a dispersant, the dispersant is adsorbed or reacted on the surface of the silica-based inorganic filler in a solution, and the surface is rendered hydrophobic, whereby the silica based in the conjugated diene-based polymer is obtained. The inorganic filler can be dispersed uniformly.
When the dispersibility of the silica-based inorganic filler is improved by the combination of the non-modified conjugated diene-based polymer and the dispersant, the degree of freedom in selecting the structure of the polymer and the type and amount of the dispersant increases. is there.
In the case of introducing a functional group having an affinity to the silica-based non-filling agent by modification, there are methods such as reacting a modifier at the end of the polymerization reaction, coupling of polymers, etc. Location and number are limited. On the other hand, when the dispersant and the polymer are mixed in the solution, the amount of the dispersant can be appropriately adjusted, and therefore, can be set according to the purpose.

Many of the modified conjugated diene polymers are modified for the purpose of facilitating dispersion of the silica-based inorganic filler, and such modified conjugated diene polymers have a conjugated diene-based polymer according to the present embodiment. The dispersibility of the silica-based inorganic filler also tends to be good when blended into the combined composition. By using a modified conjugated diene polymer, a silica inorganic filler is dispersed in a solution in which a conjugated diene polymer is dissolved in the method for producing a conjugated diene polymer composition of the present embodiment described later, and the dispersion is performed. In the step (A) of obtaining the solution, the modified portion is also adsorbed or reacted on the surface of the silica-based inorganic filler, so that a reinforcing effect is expressed by the composition containing the silica-based inorganic filler, and further the conjugation It is preferable because it contributes to reducing the hysteresis loss derived from the diene polymer and improving the fuel efficiency.
In the case of the combination of the non-modified conjugated diene polymer and the dispersant, the position at which the non-modified conjugated diene polymer and the silica-based inorganic filler are adsorbed or reacted can not be controlled. In this case, since the end of the polymer can be surely fixed to the silica-based inorganic filler, the effect of suppressing the motion of the conjugated diene-based polymer is expected to be high.
The modified conjugated diene-based polymer is conventionally supposed to have a functional group acting on the silica-based inorganic filler in the process of melt-kneading with the silica-based inorganic filler, whereas the conjugated diene of the present embodiment described later In the method for producing a polymer composition, the silica-based inorganic filler is dispersed in a solution in which a conjugated diene polymer is dissolved to act in the step (A) of obtaining a dispersion liquid, whereby the functional groups are more efficiently and uniformly It is assumed that high adsorptivity or reactivity can be exhibited.
In the case of a modified conjugated diene polymer, it is not essential to add a dispersant in the step (A), but the combined use of the modified conjugated diene polymer and the dispersant makes the silica inorganic filler more efficient. It is also possible to disperse well.

The conjugated diene-based polymer contained in the conjugated diene-based polymer composition of the present embodiment is the case of a conjugated diene-based polymer produced using a solution polymerization method, and when the polymer is modified, In the modification step, a compound having at least one functional group selected from the group consisting of an epoxy group and an alkoxysilyl group to the active end of the conjugated diene polymer obtained in the polymerization step (hereinafter referred to as “modifier” It is preferable to carry out denaturation by ").
Examples of the compound having an epoxy group which is a modifier include, but are not limited to, polyglycidyl ethers of polyhydric alcohols such as ethylene glycol diglycidyl ether and glycerin triglycidyl ether; 4,4'-diglycidyl-bisphenol A and the like Polyglycidyl ethers of aromatic compounds having two or more phenol groups; polyepoxy compounds such as 1,4-diglycidyl benzene, 1,3,5-triglycidyl benzene, polyepoxidized liquid polybutadiene; Epoxy-containing tertiary amines such as -diglycidyl-diphenylmethylamine, 4,4'-diglycidyl-dibenzylmethylamine; diglycidyl aniline, diglycidyl orthotoluidine, tetraglycidyl metaxylene diamine, tetraglycidyl amino dipheny Methane, tetraglycidyl -p- phenylenediamine, diglycidyl aminomethyl cyclohexane, diglycidyl amino compounds such as tetraglycidyl-1,3-bis-aminomethyl cyclohexane.

Among the compounds having an epoxy group described above, a polyfunctional compound having two or more epoxy groups and one or more nitrogen-containing groups in a molecule is preferable, and a compound represented by General Formula (3) described later is More preferred is a polyfunctional compound having a diglycidyl amino group.
The polyfunctional compound having a diglycidyl amino group preferably has two or more, three or more epoxy groups, and more preferably four or more epoxy groups in the molecule.

  Examples of the compound having an alkoxysilyl group include, but are not limited to, for example, dimethoxydimethylsilane, xydimethylsilane, diethoxydiethylsilane, triphenoxyvinylsilane, trimethoxyvinylsilane, triethoxyvinylsilane, tri (2-methylbutoxy) ethylsilane Tri (2-methylbutoxy) vinylsilane, triphenoxyphenylsilane, tetraphenoxysilane, tetraethoxysilane, tetramethoxysilane, tetrakis (2-ethylhexyloxy) silane, phenoxydivinylchlorosilane, methoxydiethylchlorosilane, diphenoxymethylchlorosilane, diphenoxymethylchlorosilane Phenoxyphenyliodosilane, diethoxymethyl chlorosilane, dimethoxyethyl chlorosilane, triethoxy chlorosilane, tri Phenoxychlorosilane, tris (2-ethylhexyloxy) chlorosilane, phenoxymethyldichlorosilane, methoxyethyldichlorosilane, ethoxymethyldichlorosilane, phenoxyphenyldiiodosilane, phenoxydichlorosilane, dimethoxydichlorosilane, and bis (2-methylbutoxy) ) Dibromosilane and the like.

Among the compounds having an alkoxysilyl group which is a modifier, those having an N atom and a plurality of alkoxysilyl groups in the molecule are preferable. Such compounds include, but are not limited to, for example, 2,2-dimethoxy-1- (3-trimethoxysilylpropyl) -1-aza-2-silacyclopentane, 2,2- Diethoxy-1- (3-triethoxysilylpropyl) -1-aza-2-silacyclopentane, 2,2-dimethoxy-1- (4-trimethoxysilylbutyl) -1-aza-2-silacyclohexane, 2 2, 2-Dimethoxy-1- (5-trimethoxysilylpentyl) -1-aza-2-silacycloheptane, 2,2-dimethoxy-1- (3-dimethoxymethylsilylpropyl) -1-aza-2-sila Cyclopentane, 2,2-diethoxy-1- (3-diethoxyethylsilylpropyl) -1-aza-2-silacyclopentane, 2-methoxy, 2-methyl-1- 3-trimethoxysilylpropyl) -1-aza-2-silacyclopentane, 2-ethoxy, 2-ethyl-1- (3-triethoxysilylpropyl) -1-aza-2-silacyclopentane, 2-methoxy , 2-Methyl-1- (3-dimethoxymethylsilylpropyl) -1-aza-2-silacyclopentane, 2-ethoxy, 2-ethyl-1- (3-diethoxyethylsilylpropyl) -1-aza- 2-silacyclopentane, 1- [3- (trialkoxysilyl) -propyl] -4-alkylpiperazine, 1- [3- (alkyldialkoxysilyl) -propyl] -4-alkylpiperazine, 1- [3- (Trialkoxysilyl) -propyl] -3-alkylimidazolidine, 1- [3- (alkyldialkoxysilyl) -propyl] -3-aryl Luimidazolidine, 1- [3- (trialkoxysilyl) -propyl] -3-alkylhexahydropyrimidine, 1- [3- (alkyldialkoxysilyl) -propyl] -3-alkylhexahydropyrimidine, 3- [3 3- (trialkoxysilyl) -propyl] -1-alkyl-1,2,3,4-tetrahydropyrimidine, 3- [3- (alkyldialkoxysilyl) -propyl] -1-alkyl-1,2,3 , 4-Tetrahydropyrimidine, 1- [3- (triethoxysilyl) -propyl] -4-methylpiperazine, 1- [3- (diethoxyethylsilyl) -propyl] -4-methylpiperazine, 1- [3- (Trimethoxysilyl) -propyl] -3-methylimidazolidine, 1- [3- (diethoxyethylsilyl) -propyl] -3 -Ethylimidazolidine, 1- [3- (triethoxysilyl) -propyl] -3-methylhexahydropyrimidine, 1- [3- (dimethoxymethylsilyl) -propyl] -3-methylhexahydropyrimidine, 3- [3 3- (tributoxysilyl) -propyl] -1-methyl-1,2,3,4-tetrahydropyrimidine, 3- [3- (dimethoxymethylsilyl) -propyl] -1-ethyl-1,2,3, 4-tetrahydropyrimidine, 1- (2-ethoxyethyl) -3- [3- (trimethoxysilyl) -propyl] -imidazolidine, and (2- {3- [3- (trimethoxysilyl) -propyl]- Tetrahydropyrimidin-1-yl} -ethyl) dimethylamine and the like can be mentioned.
Among these, 1- [3- (triethoxysilyl) -propyl] from the viewpoint of the reactivity and interaction between the compound functional group having an alkoxysilyl group and the inorganic filler such as silica and the processability. -4-methylpiperazine, 2,2-dimethoxy-1- (3-trimethoxysilylpropyl) -1-aza-2-silacyclopentane, and 2,2-diethoxy-1- (3-triethoxysilylpropyl) -1-Aza-2-silacyclopentane is preferred.

  Among the compounds having an alkoxysilyl group described above, compounds having a nitrogen atom and two or more alkoxysilyl groups in the molecule are more preferable, and a compound represented by General Formula (4) described later is more preferable. Among these, the modifier is represented by the following general formula (3) from the viewpoints of reactivity and interaction with the functional group of the modifier and the inorganic filler such as silica, and from the viewpoint of processability. The compound is preferably at least one compound selected from the group consisting of a compound and a compound represented by the following general formula (4).

In the formula (3), R ¹ and R ² each independently represent at least one functional group selected from the group consisting of an alkyl group having 1 to 10 carbon atoms, an ether group, and a tertiary amine group. And an alkyl group having 1 to 10 carbon atoms which has
Each of R ³ and R ⁴ independently represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an ether group, and a carbon number having at least one functional group selected from the group consisting of a tertiary amine group It represents 1 to 20 alkyl groups.
R ⁵ is a C 1 to C 1 carbon having at least one functional group selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, an ether group, a tertiary amine group, an epoxy group, a carbonyl group, and a halogen group Represents 20 alkyl groups.
n represents an integer of 1 to 6;

In the formula (4), R ¹ and R ² are each independently an alkyl group having 1 to 20 carbon atoms, or an aryl group having 6 to 20 carbon atoms.
R ³ and R ⁴ each independently represent an alkyl group having 1 to 20 carbon atoms.
R ⁵ represents an alkyl group having 1 to 6 carbon atoms, and forms a 5-membered or more ring structure with the adjacent nitrogen atom and silicon atom.
R ⁶ represents an alkyl group having 1 to 20 carbon atoms, an alkyl group having 1 to 20 carbon atoms which has no active hydrogen atom and is substituted with a hetero atom, or an organic substituted silyl group.
m represents an integer of 1 or 2; n represents an integer of 2 or 3;

Examples of the compound represented by the general formula (3) include, but are not limited to, tetraglycidyl-p-phenylenediamine, diglycidylaminomethylcyclohexane and tetraglycidyl-1,3-bisaminomethylcyclohexane. .
Examples of the compound represented by the general formula (4) include, but are not limited to, for example, 2,2-dimethoxy-1- (3-trimethoxysilylpropyl) -1-aza-2-silacyclopentane, 2 , 2-Diethoxy-1- (3-triethoxysilylpropyl) -1-aza-2-silacyclopentane, 2,2-dimethoxy-1- (4-trimethoxysilylbutyl) -1-aza-2-sila Cyclohexane, 2,2-dimethoxy-1- (5-trimethoxysilylpentyl) -1-aza-2-silacycloheptane, 2,2-dimethoxy-1- (3-dimethoxymethylsilylpropyl) -1-aza- 2-silacyclopentane, 2,2-diethoxy-1- (3-diethoxyethylsilylpropyl) -1-aza-2-silacyclopentane, 2-methoxy, 2-methyl 1- (3-trimethoxysilylpropyl) -1-aza-2-silacyclopentane, 2-ethoxy, 2-ethyl-1- (3-triethoxysilylpropyl) -1-aza-2-silacyclopentane, 2-methoxy, 2-methyl-1- (3-dimethoxymethylsilylpropyl) -1-aza-2-silacyclopentane, 2-ethoxy, 2-ethyl-1- (3-diethoxyethylsilylpropyl) -1 -Aza-2-silacyclopentane is mentioned. Among these, from the viewpoints of reactivity and interaction between the functional group of the modifier and the inorganic filler such as silica and from the viewpoint of processability, those in which m is 2 and n is 3 are more preferable, and 2, 2-Dimethoxy-1- (3-trimethoxysilylpropyl) -1-aza-2-silacyclopentane, 2,2-diethoxy-1- (3-triethoxysilylpropyl) -1-aza-2-silacyclo More preferred is pentane.

(Silica based inorganic filler)
The conjugated diene polymer composition of this embodiment has a form in which a silica based inorganic filler is dispersed in a conjugated diene polymer.
The silica-based inorganic filler is not particularly limited, but may be a known, SiO _2, or Si ₃ solid particles preferably contains Al as a constituent unit, SiO _2, or Si ₃ Al constituent units It is more preferable to use it as the main component of
Here, the main component means a component contained 50% by mass or more, preferably 70% by mass or more, more preferably 80% by mass or more in the silica-based inorganic filler.
Specific examples of the silica-based inorganic filler include inorganic fibrous substances such as silica, clay, talc, mica, diatomaceous earth, wollastonite, montmorillonite, zeolite, glass fiber and the like. Moreover, the silica-type inorganic filler which hydrophobized the surface, and the mixture of a silica-type inorganic filler and inorganic fillers other than a silica type can also be used. From the viewpoint of strength, abrasion resistance and the like, silica and glass fiber are preferable, and silica is more preferable. For example, dry silica, wet silica, synthetic silicate silica and the like can be mentioned. Among these, wet silica is preferable from the viewpoint of the balance of the fracture property and the wet skid resistance when made into a vulcanizate. Here, the silica-based inorganic filler may be surface-modified.

In the conjugated diene polymer composition of the present embodiment, the nitrogen adsorption specific surface area determined by the BET adsorption method of the silica based inorganic filler is preferably 100 to 100 from the viewpoint of obtaining practically good abrasion resistance and breaking strength. was 300m ² / g, more preferably 130~280m ² / g, more preferably from 150 to 250 ² / g.
In addition, if necessary, a combination of a relatively small specific surface area (for example, silica having a specific surface area of less than 200 m ² / g) and a relatively large specific surface area (for example, silica of 200 m ² / g or more) A silica-based inorganic filler adjusted to have the nitrogen adsorption specific surface area in the above range can be used. Thereby, good abrasion resistance, breaking strength and low heat buildup can be highly balanced.

In the conjugated diene-based polymer of the conjugated diene-based polymer composition of the present embodiment, the primary particle diameter of the silica-based inorganic filler is preferably 3 to 100 nm, more preferably 5 to 50 nm, still more preferably 10 -30 nm. When the thickness is 3 nm or more, the handling of the conjugated diene polymer composition of the present embodiment tends to be good, and when it is 100 nm or less, a good reinforcing effect tends to be exhibited.
The shape of the silica-based inorganic filler is not particularly limited, and spherical, spherical, amorphous granular, needle-like, fibrous, plate-like, etc. can be used according to the target physical properties. In the case of processing a conjugated diene polymer composition into a tire, it is preferable to use a spherical or spherical member which is less likely to exhibit anisotropy, since it is less likely to cause uneven distribution of stress concentration.

  The content of the silica-based inorganic filler in the conjugated diene-based polymer composition of the present embodiment is preferably 5 to 150 parts by mass, and more preferably 10 to 130 parts by mass with respect to 100 parts by mass of the conjugated diene-based polymer. It is a mass part, More preferably, it is 15-100 mass parts. When the content of the silica-based inorganic filler is 5 parts by mass or more, the reinforcing effect is improved. Moreover, when the content of the silica-based inorganic filler is 150 parts by mass or less, the low heat buildup is more excellent.

(Dispersant)
The conjugated diene-based polymer composition of the present embodiment preferably contains 1 to 50 parts by mass and 1 to 50 parts by mass, and more preferably 2 to 45 parts by mass with respect to 100 parts by mass of the silica-based inorganic filler. 3 to 40 parts by mass is more preferable.
The surface of the silica-based inorganic filler can be modified by the dispersant, and the dispersibility is improved.
The dispersing agent is a silica based inorganic material in the step (A) of obtaining a dispersion liquid by dispersing the silica based inorganic filler in a solution in which the conjugated diene based polymer is dissolved in the method for producing a conjugated diene based polymer composition described later It is preferable to add 1 to 50 parts by mass with respect to 100 parts by mass of the filler.
The structure and specific examples of the step (A) and the dispersant will be described later.

[Method for producing conjugated diene polymer composition]
In the method for producing a conjugated diene polymer composition of the present embodiment, a conjugated diene polymer composition in which a silica based filler is dispersed in a matrix of a conjugated diene polymer is produced.
The method for producing a conjugated diene polymer composition of the present embodiment is
In the step (A), a silica-based inorganic filler is dispersed in a solution in which a conjugated diene-based polymer is dissolved to obtain a dispersion.
Desolvating the dispersion (C);
Have.

  In addition, even if the step (B) of adding a conjugated diene polymer solution and / or an oil to the dispersion obtained in the step (A) is carried out between the step (A) and the step (C). Good.

(Softener for rubber)
As the oil to be added in the step (B), a softener for rubber (extension oil) can be applied.
Thereby, the improvement effect of the processability of the conjugated diene polymer composition of the present embodiment can be obtained.
As a softener for rubber, a mineral oil, or a liquid or low molecular weight synthetic softener is suitable. Softeners for mineral oil-based rubbers called process oils or extender oils, which are used to soften, increase the volume, and improve the processability of rubber, are a mixture of aromatic rings, naphthenic rings, and paraffin chains, A paraffin chain whose carbon number accounts for 50% or more of the total carbon is called paraffinic, a naphthenic ring having a carbon number of 30 to 45% is a naphthene, and an aromatic carbon number exceeding 30% is an aromatic It is called a system.
As a softening agent for rubber used with the conjugated diene polymer composition of the present embodiment and a master batch containing the conjugated diene polymer composition, one having an appropriate aromatic content is compatible with the conjugated diene polymer Is preferable because it tends to be good.

In the present embodiment, the timing of performing the step (B) of adding the oil is not particularly limited, and it may be a step prior to the step (C) of removing the solvent described later, and may be before the step (A). And the step following step (A).
The added oil, for example, the softener for rubber has an effect of reducing the torque in the step (C) of removing the solvent described later, and also after the solvent is removed from the dispersion liquid, the conjugated diene system is not removed. It remains with the polymer composition or masterbatch, and has the effect of improving processability when mixed with other materials.
The blending amount of the oil, for example, the softening agent for rubber, is 0 to 100 parts by mass with respect to 100 parts by mass of the rubber component containing the conjugated diene-based polymer derived from the conjugated diene-based polymer composition or masterbatch of the present embodiment. A part is preferable, 5-80 mass parts is more preferable, 10-50 mass parts is more preferable. By setting the blending amount of the oil, for example, the softening agent for rubber to 100 parts by mass or less with respect to 100 parts by mass of the rubber component, bleed out can be suppressed, and the surface of the conjugated diene polymer composition of this embodiment becomes sticky. It can be prevented from occurring.

(Step (A))
In the method for producing a conjugated diene polymer composition according to this embodiment, the silica inorganic mineral is dispersed in a solution in which the conjugated diene polymer is dissolved (sometimes described as a conjugated diene polymer solution). Step (A) to obtain a dispersion.

<Solution of conjugated diene polymer>
The solution in which the conjugated diene-based polymer in step (A) is dissolved contains the conjugated diene-based polymer and a solvent.
The solvent is not particularly limited, and examples thereof include C4 to C8 hydrocarbon solvents, toluene and xylene. Furthermore, the solvent may have a cyclic structure, or may have an unsaturated bond or a branched structure. A C5 or C6 hydrocarbon solvent is preferable, and pentane, normal hexane, and cyclohexane are more preferable because the boiling point and the vapor pressure are easy to handle in the production process. These may be used alone or in combination of two or more. In the case of a conjugated diene-based polymer produced using a solution polymerization method, the solvent is preferably the same as that used in the polymerization step of the conjugated diene-based polymer from the viewpoint of simplification of the production process. That is, it can be used as it is, without removing a solvent from the solution which performed the polymerization reaction and the modification reaction as needed.
The solution in which the conjugated diene polymer is dissolved preferably contains 10% by mass to 99% by mass, more preferably 30% by mass, of the solvent based on the total amount (100% by mass) of the conjugated diene polymer solution. More than 98 mass% or less, more preferably 50 mass% or more and 97 mass% or less are included. By containing the solvent in an amount of 10% by mass or more, the viscosity at the time of dispersing by the disperser is reduced, and the dispersion of the silica-based inorganic filler can be further advanced. On the other hand, by containing 99% by mass or less, the amount of solvent volatilized in step (C) of removing the solvent described later can be reduced, and the load on the process can be reduced.

<Polar compound>
The polar compound added in the polymerization step by the solution polymerization method may coexist in the solution in which the conjugated diene polymer is dissolved in the step (A).
The polar compound can also be used to randomly copolymerize an aromatic vinyl monomer with a conjugated diene monomer in a polymerization step by a solution polymerization method, and a vinyl for controlling the microstructure of a conjugated diene moiety It can also be used as an agent. It is also effective in improving the polymerization rate.
Examples of polar compounds include, but are not limited to, tetrahydrofuran, diethyl ether, dioxane, ethylene glycol dimethyl ether, ethylene glycol dibutyl ether, diethylene glycol dimethyl ether, diethylene glycol dibutyl ether, diethylene glycol dibutyl ether, dimethoxybenzene, 2,2-bis (2-oxolanyl) propane Ethers such as tetramethylethylenediamine, dipiperidinoethane, trimethylamine, triethylamine, tertiary amines such as pyridine, quinuclidine and the like; potassium t-amylate, potassium t-butylate, sodium t-butylate, sodium ami And alkali metal alkoxide compounds such as borate; and phosphine compounds such as triphenylphosphine. These polar compounds may be used alone or in combination of two or more.
The addition amount of the polar compound is not particularly limited and can be selected according to the purpose etc., but is preferably 0.01 mol or more and 100 mol or less with respect to 1 mol of the polymerization initiator. In addition, an appropriate amount of a polar compound (vinylating agent) can be used as a regulator of the microstructure of the conjugated diene portion of the polymer, depending on the desired vinyl bond amount.
Many polar compounds have an effective randomization effect in the copolymerization of a conjugated diene monomer and an aromatic vinyl monomer, and a regulator of the distribution of the aromatic vinyl monomer and a regulator of the amount of styrene block It can also be used as
The method for randomizing the conjugated diene monomer and the aromatic vinyl monomer is not particularly limited. For example, as described in JP-A-59-140211, 1 in the middle of copolymerization And a method of intermittently adding a part of 3-butadiene.

Stabilizers
In the step (A), from the viewpoint of preventing the formation of a gel during storage with respect to the conjugated diene polymer solution and the conjugated diene polymer solution, and from the viewpoint of improving the stability during processing, stability for rubber Agents may be coexistent.
As the stabilizer for rubber, known ones can be used, and it is not limited to the following, for example, 2,6-di-tert-butyl-4-hydroxytoluene (BHT), n-octadecyl-3 Antioxidants such as-(4'-hydroxy-3 ', 5'-di-tert-butylphenol) propionate and 2-methyl-4,6-bis [(octylthio) methyl] phenol are preferred.
These may be used alone or in combination of two or more.

<Silica based inorganic filler>
In the step (A), as the silica-based inorganic filler, those described above can be used.
In the method for producing a conjugated diene-based polymer composition of the present embodiment, the content of the silica-based inorganic filler in a dispersed state in the conjugated diene-based polymer composition is adopted by adopting the method via the step (A) Tends to be able to Therefore, when preparing a conjugated diene-based polymer composition containing a silica-based inorganic filler, a conjugated diene-based polymer composition which is richer in silica than the target substance is prepared in advance, and this is used as a masterbatch and the polymer And the like may be appropriately added and kneaded to prepare a target conjugated diene polymer composition.
Further, in step (A), a dispersion of a conjugated diene-based polymer in silica, which is richer in silica than the target substance, is prepared in advance, and a predetermined amount of conjugated diene-based polymer solution is appropriately added to this to prepare a solvent. By volatilizing, the target conjugated diene polymer composition can also be produced.
In addition, when implementing the process which removes a solvent by steam stripping in the process (C) mentioned later, especially when there is much silica content, it is possible that silica absorbs water and reaggregates, The use of a devolatilizing twin-screw extruder described later is preferable from the viewpoint that it is easy to obtain a composition richer in silica and having good dispersibility, since steam stripping is not required. In addition, by using a devolatilizing twin-screw extruder, there is also a merit that extrusion can be performed while suppressing an increase in torque, even in a formulation in which the silica content is large and the torque tends to increase.

<Dispersing agent>
Step (A) is preferably carried out in the presence of a dispersant.
In the step (A), the dispersant is preferably added in an amount of 1 to 50 parts by mass, more preferably 2 to 45 parts by mass, still more preferably 3 to 40 parts by mass with respect to 100 parts by mass of the silica based inorganic filler. It is a department.
The surface of the silica-based inorganic filler can be modified by the dispersant to improve the dispersibility.
The surface modification of the silica-based inorganic filler with the dispersing agent may be performed by attaching a predetermined functional group to the surface of the silica-based inorganic filler through a chemical reaction, or using a physical method of dispersing the dispersant through the mixing or adsorption. Bond to the surface of the filler. For example, Wang W, Nanse G, Vidal A, et al. K. G. As described in K [J], 1994, 47: 493, a method in which a dispersant is dissolved in a solvent and then mixed with a silica-based inorganic filler and reformed in a liquid phase, for example, Wang MJ, Wolff. S. R. C. As described in T [J], 1992, 65: 715, a method of mixing the dispersant with the silica-based inorganic filler and heating and modifying with a solid phase is included, but not limited thereto.
As such a dispersing agent, what is represented by the following general formula (1) or (2) is mentioned.

(R ¹ ) _m Si (OR ² ) _4-m (1)
(In the general formula (1), R ¹ is a substituted or unsubstituted monovalent hydrocarbon group, and when a plurality of R ¹ is contained, they may be each independently the same or different. R ² is carbon It is an alkyl group of the number 1 to 4, and when a plurality of R ² is contained, they may be independently the same or different from each other m is an integer of 0 to 3 and n is an integer of 0 to 2 is there.)

R ³ Si (R ⁴ ) _n (OR ⁵ ) _3-n (2)
(In the general formula (2), R ³ is a linear or branched alkyl group having 8 to 30 carbon atoms, R ⁴ is a substituted or unsubstituted monovalent hydrocarbon group, and when a plurality of R ⁴ is contained, Each R ⁵ may be the same or different from each other R ⁵ is an alkyl group having 1 to 4 carbon atoms, and when a plurality of R ⁵ are contained, they may be each independently the same or different m. Is an integer of 0 to 3, and n is an integer of 0 to 2.)

In the silane compound of the general formula (1), R ¹ is a monovalent hydrocarbon group which may have a substituent, preferably a linear or branched chain having 1 to 7 carbon atoms which may have a substituent It represents a branched alkyl group or aryl group. Specific examples thereof include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a sec-pentyl group, a neopentyl group, a hexyl group, a heptyl group, A phenyl group, o-tolyl group, m-tolyl group, p-tolyl group, a benzyl group etc. are mentioned.

In the general formula (1), R ² is an alkyl group having 1 to 4 carbon atoms. As a specific example, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group etc. are mentioned.
In the general formula (1), m is an integer of 0 to 3, and in the case of m = 0, it is tetraalkoxysilane.

  Examples of the silane compound of the general formula (1) include, but are not limited to, tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetrabutoxysilane, methyltrimethoxysilane, methyltriethoxysilane, for example. Methyltripropoxysilane, ethyltrimethoxysilane, propyltrimethoxysilane, butyltrimethoxysilane, pentyltrimethoxysilane, hexyltrimethoxysilane, 2-ethylhexyltrimethoxysilane, phenyltrimethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane And trimethylmethoxysilane, triethylmethoxysilane and butyldimethylmethoxysilane.

In the silane compound of the general formula (2), R ³ is a linear or branched alkyl group having 8 to 30 carbon atoms. As R ³ , for example, n-octyl group, n-decyl group, n-dodecyl group (lauryl group), n-tetradecyl group (myristyl group), n-hexadecyl group (cetyl group), n-octadecyl group (stearyl) Groups, 1-hexyl-hexyl group, 4-hexyl-cyclohexyl group, 3-hexyl-1-norbornyl group, n-triacontyl group, n-icosanyl group and the like.

In the silane compound of the general formula (2), R ⁴ is a monovalent hydrocarbon which may have a substituent, preferably a linear or branched chain having 1 to 7 carbon atoms which may have a substituent It represents a branched alkyl group or aryl group. As a specific example, the thing similar to the example of R ¹ of General formula (1) is mentioned.
In the general formula (2), R ⁵ is an alkyl group having 1 to 4 carbon atoms. As a specific example, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group etc. are mentioned.
In said General Formula (2), n is an integer of 0-2.

  Examples of the silane compound of the general formula (2) include, but are not limited to, octyl trimethoxysilane, n-decyltrimethoxysilane, n-dodecyltrimethoxysilane, n-tetradecyltrimethoxysilane, for example. , N-hexadecyltrimethoxysilane, n-octadecyltrimethoxysilane, 1-hexyl-hexyltriethoxysilane, 4-hexyl-cyclohexyltrimethoxysilane, 3-hexyl-1-norbornyltrimethoxysilane, n-tria Contilly methoxysilane, n-icoisanyl trimethoxysilane, n-dodecylmethyldimethoxysilane, n-tetradecylmethyldimethoxysilane, n-hexadecylmethyldimethoxysilane, n-octadecylmethyldimethoxysilane and the like.

<Coupling agent>
When the conjugated diene polymer composition of the present embodiment is vulcanized to be used, for example, in a tire, it is known to include a coupling agent in the rubber component.
In the method for producing a conjugated diene polymer composition of the present embodiment, using a dispersant having a coupling ability with a rubber component as a part or all of the dispersant added in the step (A) is a conjugate It is preferable because the dispersibility of the silica-based inorganic filler in a diene-based polymer composition or a master batch can be improved, and the reinforcing effect of the rubber can be improved when it is made into a vulcanized product.
As such a dispersing agent having a coupling ability, a conventionally known dispersing agent (silane coupling agent) can be used, and although it is not limited to the following, for example, bis (3-triethoxysilyl) can be used. Propyl) tetrasulfide, bis (2-triethoxysilylethyl) tetrasulfide, bis (4-triethoxysilylbutyl) tetrasulfide, bis (3-trimethoxysilylpropyl) tetrasulfide, bis (2-trimethoxysilylethyl) Tetrasulfide, bis (4-trimethoxysilylbutyl) tetrasulfide, bis (3-triethoxysilylpropyl) trisulfide, bis (2-triethoxysilylethyl) trisulfide, bis (4-triethoxysilylbutyl) trisulfide , Bis (3-trimethoxysilyl Pill) trisulfide, bis (2-trimethoxysilylethyl) trisulfide, bis (4-trimethoxysilylbutyl) trisulfide, bis (3-triethoxysilylpropyl) disulfide, bis (2-triethoxysilylethyl) disulfide , Bis (4-triethoxysilylbutyl) disulfide, bis (3-trimethoxysilylpropyl) disulfide, bis (2-trimethoxysilylethyl) disulfide, bis (4-trimethoxysilylbutyl) disulfide, 3-trimethoxysilyl Propyl-N, N-dimethylthiocarbamoyl tetrasulfide, 3-triethoxysilylpropyl-N, N-dimethylthiocarbamoyl tetrasulfide, 2-triethoxysilylethyl-N, N-dimethylthiocarbamoyl tetrase Fide, 2-trimethoxysilylethyl-N, N-dimethylthiocarbamoyl tetrasulfide, 3-trimethoxysilylpropylbenzothiazolyl tetrasulfide, 3-triethoxysilylpropylbenzothiazole tetrasulfide, 3-trimethoxysilylpropyl methacrylate Sulfide systems such as monosulfide; 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 2-mercaptoethyltrimethoxysilane, 2-mercaptoethyltriethoxysilane, mercapto such as 8-mercaptooctanoyltriethoxysilane And the like. As a sulfide type silane coupling agent, Si75, Si69 made by Evonik Degussa, etc. may be mentioned, and as a mercapto type silane coupling agent, NXT-Z100 made by Momentive, NXT-Z45, NXT, made by Evonik Degussa Si363 etc. are mentioned.
One of these dispersants (silane coupling agents) may be used alone, or two or more thereof may be used in combination in consideration of the desired dispersibility and the physical properties of the vulcanizate.
The addition amount of the coupling agent is not particularly limited and can be determined in consideration of the desired degree of dispersion, physical properties of the vulcanized product, cost and the like, but it is 1 to 50 mass with respect to 100 mass parts of the silica type inorganic filler. A part is preferable, More preferably, it is 2-40 mass parts, More preferably, it is 3-30 mass parts.

<Distributed operation in step (A)>
In the step (A) of the method for producing a conjugated diene polymer composition of the present embodiment, the silica based inorganic filler is finely dispersed in a conjugated diene polymer solution. The method for the dispersion is not particularly limited. For example, medium agitation mills such as high-speed rotational shear stirrer, colloid mill, roll mill, high pressure jet disperser, ultrasonic wave disperser, container driven mill such as ball mill, bead mill etc. And the like. In particular, a method using a medium stirring mill such as a bead mill is preferable because fine dispersion can be performed under relatively mild conditions and temperature control is easy.

In step (A), the size of the beads when using a bead mill affects the final particle size of the silica-based inorganic filler in a solution of conjugated diene-based polymer. As is known in the pigment dispersion art represented by paints, the dispersion process with a bead mill is carried out by the collision of the composition to be dispersed with the beads. Larger beads have larger gaps between them when the beads are packed together, so if the average particle size of the silica-based mineral filler is smaller than this volume, the particles will simply get into the voids of the milling beads, It can not be crushed any more. From this point of view, the average bead diameter in the step (A) is preferably 0.05 mm to 2.0 mm, more preferably 0.1 mm to 1.5 mm, and still more preferably 0.1 mm to 1.0 mm. It can be selected appropriately according to the particle size of the filler, and a plurality of inorganic fillers having different particle sizes may be added.
The material of the bead is not particularly limited, but can be selected in consideration of its specific gravity, uniformity, and wear resistance over long-term use, as known in the art of pigment dispersion represented by paint. Preferably, zirconium oxide beads are used.

  In the step (A), when dispersion treatment is performed using a bead mill, another operating condition that affects the final particle size of the silica-based inorganic filler includes the filling rate of beads introduced into the bead mill. In detail, the packing ratio of beads refers to the ratio of the volume of charged beads to the volume in the bead mill. As the packing rate is higher, the number of beads is increased and the contact frequency is increased, so that the speed of crushing and dispersion tends to be faster. On the other hand, it is necessary to select an appropriate range because it may lead to heat generation of the solution, abrasion of members in the apparatus, and further molecular chain breakage of the conjugated diene polymer, and it depends on the characteristics of the bead mill used. Generally, it is selected between 0.5 and 0.9.

  In dispersion treatment using a bead mill in step (A), the circumferential speed of the agitator is also mentioned as an operating condition that affects the final particle size of the silica-based inorganic filler, in addition to the above-mentioned bead packing rate. If the agitator circumferential speed is fast, the kinetic energy transferred to the beads increases and the frequency of contact between the beads also increases, so the rate of crushing and dispersion tends to increase, while the heat generation of the solution and the wear of the members in the apparatus, Furthermore, because it may lead to molecular chain cleavage such as conjugated diene copolymerization, it is necessary to select an appropriate range, and depending on the properties of the bead mill used, it is generally selected between 6 and 15 m / s. .

  In the step (A), when the dispersion treatment with beads is carried out, the dispersion viscosity can generally be adjusted by the solid content concentration in the dispersion. If the viscosity is too high, heat generation will occur, and it may be necessary to lower the solid concentration, but on the other hand the solution throughput required to collect the desired solid will increase, so the viscosity range permitted by the equipment used It is necessary to adjust the concentration to an appropriate concentration, and it is generally 5 to 5000 mPas, more preferably 10 to 3000 mPas, and still more preferably 20 to 1000 mPas, depending on the properties of the bead mill used. . Dispersion liquid viscosity can be measured, for example, using an ARG2 rheometer with a light weight aluminum cone (60 mm diameter with an angle of 1 °).

(Step (B))
In the method for producing the conjugated diene polymer composition of the present embodiment, the dispersion liquid of the conjugated diene polymer in which the silica inorganic filler is dispersed, which is obtained in the step (A) described above, is used as needed. The step (B) of adding a conjugated diene polymer solution, the above-mentioned oil, a softener for rubber, a stabilizer and the like can be carried out.
In the step (B), a conjugated diene-based polymer in a conjugated diene-based polymer composition or a master batch, a silica-based inorganic filler, a dispersant, a softener for rubber, which is taken out in the step (C) described later A dispersion or solution having a adjusted composition such as a stabilizer is prepared.
In addition, if it is before the process (C) to remove a solvent mentioned later, a process (B) can further be performed at arbitrary timing, and you may implement as a process before a process (A).

<Conjugated diene polymer solution>
The conjugated diene polymer solution added in the step (B) refers to a solution containing a conjugated diene polymer and a solvent.
The conjugated diene-based polymer in the conjugated diene-based polymer solution to be added in the step (B) is not particularly limited, but may be a homopolymer obtained by polymerizing a conjugated diene monomer. The conjugated diene monomer is not particularly limited as long as it is a polymerizable monomer, and, for example, 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 3-Methyl-1,3-pentadiene, 1,3-heptadiene, and 1,3-hexadiene can be mentioned. Among these, 1,3-butadiene and isoprene are preferable from the viewpoint of industrial availability. These may be used alone or in combination of two or more.
Here, it may be the same as or different from that used in the step (A) described above.

  Although it does not specifically limit as a solvent of the conjugated diene type polymer solution added in process (B), For example, the C4-C8 hydrocarbon solvent, toluene, and xylene are mentioned. Furthermore, the solvent may have a cyclic structure, or may have an unsaturated bond or a branched structure. A C5 or C6 hydrocarbon solvent is preferable, and pentane, normal hexane, and cyclohexane are more preferable because the boiling point and the vapor pressure are easy to handle in the production process. It is preferable that it is the same solvent as what was used by the above-mentioned process (A) from a viewpoint of a manufacturing process simplification.

The conjugated diene polymer solution to be added in the step (B) preferably contains 1.0% by mass or more and 99% by mass or less of the solvent based on the total amount (100% by mass) of the conjugated diene polymer solution. More preferably, it is 30 mass% or more and 98 mass% or less, More preferably, it is 50 mass% or more and 97 mass% or less.
By containing the solvent in an amount of 1.0% by mass or more, the uniform mixing with the dispersion obtained in the above-mentioned step (A) tends to be quick, and by containing 99% by mass or less, volatilization in the step (C) described later Because the amount of solvent to be reduced decreases, it leads to rate up. Here, it is preferable that the viscosity of the dispersion obtained in the step (A) and the viscosity of the conjugated diene polymer solution added in the step (B) be as close as possible because uniform mixing tends to be faster.

  When an oil such as a softener for rubber is added in the step (B), the amount thereof is 100 parts by mass of the conjugated diene polymer derived from the conjugated diene polymer composition or the master batch of the present embodiment. 0 to 100 parts by mass is preferable, 5 to 80 parts by mass is more preferable, and 10 to 50 parts by mass is more preferable. If the amount of the oil, for example, the softener for rubber added is 100 parts by mass or less with respect to 100 parts by mass of the conjugated diene polymer, the occurrence of bleed out can be suppressed, and the composition surface becomes sticky. It can prevent.

  In the step (B), a stabilizer for rubber may be added to the conjugated diene polymer from the viewpoint of preventing the formation of a gel during storage and the viewpoint of improving the stability during processing. As the stabilizer for rubber, known ones can be used, and it is possible to use, but not limited to, for example, 2,6-di-tert-butyl-4-hydroxytoluene (BHT), n-octadecyl- Antioxidants such as 3- (4'-hydroxy-3 ', 5'-di-tert-butylphenol) propionate and 2-methyl-4,6-bis [(octylthio) methyl] phenol are preferred.

(Step (C))
In the step (C), the solvent is volatilized from the dispersion of the conjugated diene polymer composition or masterbatch obtained in the step (A) or the step (B) described above, and the conjugated diene polymer as a solid content It is a process of obtaining a composition or a masterbatch.

<Volatilization method>
Step (C) includes steam stripping, a flash tank, a thin film type concentrator, a drum dryer, a concentration vessel with a stirring blade, a devolatilizing twin-screw extruder, etc. The method of using a devolatilizing twin-screw extruder is preferable from the viewpoint of low shear property and dispersion form maintenance.

In the case of desolvation using a devolatilization twin-screw extruder as step (C), the dispersion prepared in step (A) and step (B) is heated while being conveyed by an apparatus having a rotating twin screw. And remove the solvent contained in the dispersion. Further, it is desirable that the motor current value of the screw and the motor current value of the screw at no load in the step (C) satisfy the following relational expression (II).
1.05 ≦ ((I ₁ ) / (I ₀ )) ≦ 2.00 (II)
In the formula (II), I ₁ represents the motor current value [A] of the screw in the volatilization step (C), and I ₀ represents the motor current value [A] of the screw at no load.
In step (C), a conjugated diene polymer composition or a masterbatch obtained by devolatilizing the solvent to an appropriate residual volatile content while suppressing gel formation and molecular chain breakage of the conjugated diene polymer is obtained. it can. The volatilized conjugated diene-based polymer composition or masterbatch may have a suitable residual volatile content, and may contain a solvent. Further, the appearance of the devolatilized composition may be any of solid, powder, liquid and the like.

  Although it does not specifically limit as an apparatus which has the said twin screw, For example, the screw extruder used for resin kneading | mixing, a screw kneader, and the thing of the structure similar to these are mentioned. In particular, the number of screws in the extruder is preferably two.

In the step (C), in addition to the method using an apparatus having a twin screw, another method of degassing the solvent may be used in combination, and in the case of using such another method, the solvent is removed The device may be used before and / or after a device having twin screws, depending on the desired progression of degassing.
Further, in the step (C), it is preferable to use two or more units having a twin screw from the viewpoint of the amount of residual volatile component of the devolatilized conjugated diene polymer composition or the master batch. In this case, there is a method in which an apparatus having two or more twin screws is connected in series and the dispersion is fed continuously, or a method in which each apparatus is treated batchwise. Is more preferable in terms of production efficiency. As a device for transferring the dispersion liquid in a continuous manner, for example, a pump such as a gear pump, a screw type device such as a twin screw extruder, and a conveyor can be exemplified. When two or more apparatuses are connected to degas in a continuous manner, the degassing conditions such as temperature and pressure may be different for each apparatus. In general, since the heating rate is limited by the step (C) at the initial stage of concentration, an apparatus capable of obtaining a wide heat transfer area is more preferable. For this purpose, it is more preferable to make the screw surface a heat transfer part by passing the heat medium through the hollow state of the screw. Solids may precipitate as the concentration progresses. In that case, in order to devaporize the solvent contained in the solid, the solid is required to have a function of applying shear and resurfacing.

In step (C), the dispersion is heated while being transported by a rotating twin screw, and the motor current value (I ₁ ) at the time of devolatilizing the solvent, and the inside of the apparatus having the twin screw is empty. in rotational power, i.e. no-load current value when rotating the screw (I ₀₎ and the ratio of _{(I 1) / (I 0} ) , by satisfying the following relational expression (II), the gel The solvent can be devolatilized to an appropriate residual volatile content while suppressing formation and molecular chain breakage of the conjugated diene polymer.
1.05 ≦ ((I ₁ ) / (I ₀ )) ≦ 2.00 (II)
By setting (I ₁ ) / (I ₀ ) to 1.05 or more, the surface of the conjugated diene-based polymer composition can be appropriately renewed, and the devolatization of the solvent can be promoted. On the other hand, gel formation and molecular chain scission of a conjugated diene polymer can be suppressed by setting (I ₁ ) / (I ₀ ) to 2.00 or less. Furthermore, (I ₁ ) / (I ₀ ) is preferably 1.10 or more and 1.80 or less, and is 1.20 or more and 1.60 or less from the viewpoint of the balance between solvent degassing property and thermal deterioration. Is more preferred.
Note that (I ₁ ) does not have to be a constant value as long as the relational expression (II) is satisfied, and it may be a variable value. The (I ₁ ) / (I ₀ ) tends to increase as the packing ratio of the conjugated diene polymer composition or the mixture of the masterbatch and the solvent in the apparatus or the number of rotations of the screw increases. Also, (I ₁ ) / (I ₀ ) can be adjusted also by the shape of screw, screw diameter, screw length, gap between body and screw, feed rate of mixture of master batch and solvent, etc. . When rotating a plurality of screws, the rotation direction may be the same or opposite, and the rotation speed may be the same or different, but from the viewpoint of preventing adhesion of the polymer to the screw, the rotation direction is the reverse direction, It is preferable that the rotational speeds be different.

  In the step (C) using an apparatus having a twin screw, the average residence time is preferably 5.0 seconds or more and 300 seconds or less from the viewpoint of the balance between the solvent removal property and the thermal deterioration, and is preferably 10 seconds or more It is more preferable that it is 250 seconds or less, and it is further more preferable that it is 20 to 200 seconds.

The step (C) is preferably a step of devolatilizing the content of the solvent to 5.0% by mass or less based on the total amount (100% by mass) of the conjugated diene polymer composition to be obtained. It is more preferable that it is a process of devolatilizing to 0.5 mass% or less.
Further, in the step (C), it is preferable that the internal volume of the apparatus having a twin screw and the amount of solvent volatilized per unit time satisfy the following relational expression (III).
1.0 ≦ ((V _A ) / (V ₀ )) ≦ 50 (III)
In formula (III), (V ₀ ) represents the internal volume [L] of the device, and (V _A ) represents the amount of solvent [L] that volatilizes per unit time [h].

  When an apparatus having a screw is used in the step (C), the ratio of the screw length (L) to the screw diameter (D) (hereinafter referred to as “L / D”) from the viewpoint of preventing clogging of the vent pipe It is preferable that it is 4.0 or more and 12 or less, and it is more preferable that it is 5.0 or more and 10 or less. When L / D is 4.0 or more, the degassing ability tends to be high, and when L / D is 12 or less, the amount of gel formation and the molecular chain breakage of the conjugated diene polymer are suppressed. Tend to be In addition, although a biaxial screw is a screw in which a ratio is in the said range independently, it is preferable that the diameter and screw length of a screw are the same.

The rotating screws may have the same or opposite rotation directions, and may have the same or different rotation speeds, but from the viewpoint of preventing adhesion of the polymer to the screws, the rotation directions may be reversed. More preferably, the directions and rotational speeds are different.
When two or more units having the above screw are used, L / D may be independently 4.0 or more and 12 or less. In addition, even if it is an apparatus in which L / D is not in such a range, you may use in combination with the apparatus which has said screw.

In step (C), the internal volume (V ₀ ) of the device having the above screw with respect to the amount of solvent (V _A ) [L] (hereinafter simply referred to as “V _A ”) which volatilizes per unit time [h]. [L] (hereinafter, also simply expressed as "V ₀ ") ratio (((V _A ) / (V ₀ )), hereinafter, simply expressed as "(V _A ) / (V ₀ )" By satisfying the relational expression (III), it is possible to devolatize the solvent to an appropriate residual volatile content while preventing clogging of the vent pipe due to the venting of the masterbatch solution.
1.0 ≦ ((V _A ) / (V ₀ )) ≦ 50 (III)
When (V _A ) / (V ₀ ) is 1.0 or more, thermal degradation and gelation, and molecular chain breakage of the conjugated diene polymer tend to be suppressed. In addition, when (V _A ) / (V ₀ ) is 50 or less, there is a tendency that the venting up of the dispersion can be suppressed.
Furthermore, (V _A ) / (V ₀ ) is more preferably 5.0 or more and 45 or less, and preferably 10 or more and 30 or less, from the viewpoint of the balance between the degassing property, thermal degradation, and molecular chain cleavage. More preferable.
The _VA does not have to be a constant value as long as the above relation (III) is satisfied, and may be a variable value. In addition, a vent up is a phenomenon in which a dispersion containing a conjugated diene polymer composition passes through a vent opening and flows into a vent pipe, and when the dispersion attached to the surface of the inner wall of the pipe is dried. The solid composition remains on the surface. When the vent up continues to occur, the composition is deposited on the inner wall of the vent pipe, and the vent pipe is eventually blocked. When the vent pipe is blocked, the discharge of the solvent gas evaporated from the solution in the apparatus is hindered, and the amount of residual volatile component of the composition may be increased since the solvent gas is not sufficiently devaporized.

V ₀ is the volume of the device body minus the volume of the screw. The volume of the device body does not include the volume of the jacket for heating and cooling the body and the piping connected to the device. The piping connected to the device refers to all the piping connected to the device, specifically, the piping for supplying the solution of the masterbatch, and the concentrate and composition of the solution after devolatilization are sent out of the device Piping for supplying the devolatized solvent gas to the outside of the apparatus. V ₀ can be adjusted by expanding or contracting all or part of the torso. In addition, when the value of V _A is large, the value of V ₀ is increased by providing a space for the solvent gas to stay in a part of the body of the apparatus, and (V _A ) / (V ₀ ) is obtained. It can be adjusted to an appropriate range.
From the viewpoint of the degassing property, V ₀ is preferably 1.0 or more, more preferably 5.0 or more, and still more preferably 10 or more. Further, from the viewpoint of the amount of leaked air under reduced pressure degassing conditions in which the pressure in the apparatus is reduced, the value is preferably 500 or less, more preferably 400 or less, and still more preferably 300 or less.

_VA is the volume of solvent recovered by cooling and liquefying the solvent gas discharged from the vent port of the apparatus through the vent pipe. A cooler such as a condenser can be used for cooling and liquefying the solvent gas. The solvent composition of the master batch solution supplied to the apparatus having a screw is larger, and the larger the amount of supply, the larger the _VA tends to be. In addition, the temperature heated by the device having a screw is high, and the pressure in the device tends to increase even when the pressure is low.

When two or more units having the above screws are used, V _A , V ₀ and V _A / V ₀ are calculated independently, and each V _A / V ₀ is in the range described above. Just do it. Further, the unit of V _A time when using the apparatus two or more groups, as the basis of a unit time of each V _A the total time operation all devices when connecting in series, the process batchwise If so, the time spent processing each device is based on the unit time of each _VA . In addition, even if it is an apparatus which does not have V _A / V ₀ in such a range, ie, the apparatus which has a screw of this embodiment, you may use it together with the apparatus which has said screw.

  The apparatus having a twin screw preferably has one or more vent ports for exhausting the solvent gas component that has been vaporized out of the apparatus. The degassed gas is discharged from the vent port, then cooled and condensed by a cooler or the like, and may be recovered and reused as a liquid. As the masterbatch powder adheres to the vent port, the exhaust rate may decrease, so an apparatus for removing the adhering powder may be attached to the vent port. As an apparatus which specifically removes powder, the scraper and rotor which rotate along the inner wall face of a vent port are mentioned, for example. A mixture of the composition and the solvent can be heated by flowing a heat medium such as high temperature steam or oil through a jacket of an apparatus having a twin screw. The temperature of the heat medium at this time is preferably 50 ° C. or more and 300 ° C. or less from the viewpoint of the degassing rate, and more preferably 100 ° C. or more and 200 ° C. or less from the viewpoint of mixture transportability and gel suppression. The temperature of the composition to be volatilized is in these ranges, but may be lower than these ranges because of the heat of vaporization heat involved in solvent volatilization.

The pressure of the gas phase part when the solvent degasses is preferably not higher than normal pressure from the viewpoint of the degassing rate, but from the viewpoint of degassing rate and entrainment prevention by the solvent gas of the composition, etc. It is preferable that it is the following. In order to control the pressure, for example, a vacuum pump can be connected to the vent port through piping.
If the composition solution is heated before being supplied to the apparatus having a screw, the degassing rate tends to be improved, which is preferable. The heating temperature is not particularly limited, but if the solution is heated above the boiling point of the solvent at the pressure in the apparatus, the degassing rate tends to be high, and heating by 50 ° C. or more higher than the boiling point of the solvent is more It is more preferable to heat 80 degreeC or more higher preferably than the boiling point of this solvent. Moreover, it is preferable to heat at 140 degrees C or less, and it is more preferable to heat at 120 degrees C or less from a viewpoint of preventing entrainment of the composition at the time of volatilization in the said apparatus. As a specific example, when the solvent in the conjugated diene polymer solution is hexane and the pressure in the apparatus having a twin screw is 400 torr, the boiling point of hexane at 400 torr is about 50 ° C. The combined solution may be heated to 50 ° C. or higher.

<Pre-concentration>
The dispersion of the conjugated diene-based polymer composition or the masterbatch can also be concentrated in a device without twin screws before being fed to the device with twin screws in step (C). The apparatus includes, for example, a flash tank, a thin film concentrator, a drum dryer, and a concentration container with a stirring blade.

The shape of the discharge port for discharging the conjugated diene polymer composition or masterbatch after volatilization out of the apparatus having a twin screw is not particularly limited, but the area of the discharge port and the position of the discharge port By adjusting, the discharge amount can be controlled and the motor current value can be controlled. Moreover, in order to prevent deterioration due to heat and oxygen in the atmosphere, it is preferable to store under an inert gas atmosphere or under an environment of reduced pressure.
The remaining volatile content of the devolatilized conjugated diene polymer composition is 0.001% by mass or more and 5.0% by mass or less with respect to the total amount (100% by mass) of the composition. It is preferable from the viewpoint of workability at the time of processing it into a product. The residual volatile component may contain water in addition to the raw material such as the solvent used for polymerization and dispersion.

[Physical Properties of Conjugated Diene-Based Polymer Composition]
(Pain effect (ΔG '))
The dispersibility of the silica-based inorganic filler in the conjugated diene-based polymer composition of the present embodiment was measured according to ASTM D6204 using an unvulcanized visco-elastic device "RPA 2000 (manufactured by ALPHA TECHNOLOGIES)". It can be evaluated by the Payne effect ΔG ′ (MPa) obtained as a difference between storage modulus (G ′) values of 07% strain and 1200% strain.
The Payne effect is usually used to obtain information about filler-filler interactions in the rubber matrix, and the higher the storage modulus (G ') value at low strain, the more filler-filled. Agent interactions are higher. During strain sweep measurements, the storage modulus value is reduced due to the failure of the filler-filler network and at large strain despite the small strain-initiated filler-filler interaction. The same G 'value as obtained is obtained.
Here, the Payne effect (ΔG ') and the storage elastic modulus (G') at small strain are not only the dispersibility of the silica-based inorganic filler in the conjugated diene-based polymer composition but also the volume of the silica-based inorganic filler The value tends to increase as the volume fraction (φ) of the silica based inorganic filler fluctuates depending on the fraction (φ). The volume fraction (φ) of the silica-based inorganic filler in the conjugated diene-based polymer composition is, for example, the ash content (the amount of component remaining without burning when the conjugated diene-based polymer composition or the masterbatch is burned) Measurement can be performed by converting the weight fraction of the silica-based inorganic filler quantified by a known quantitative analysis method using fluorescent X-rays or a known ICP analysis method into a volume fraction.

In the conjugated diene polymer composition according to this embodiment, the above-mentioned Payne effect ΔG ′ (MPa) and volume fraction φ (vol%) satisfy the relationship of the following formula (I).
ΔG ′ <0.250 × exp (0.162 × φ) (I)

The range of ΔG ′ is preferably ΔG ′ <0.200 × exp (0.162 × φ), and more preferably ΔG ′ <0.150 × exp (0.162 × φ).
When ΔG ′ is less than the above upper limit value, a conjugated diene polymer composition in which the silica-based inorganic filler is more dispersed is more preferable.
The lower limit value of ΔG ′ is not particularly limited from the viewpoint of the dispersibility of the silica-based inorganic filler, but from the viewpoint of sufficiently expressing the rigidity of the conjugated diene-based polymer composition, 0.0100 × exp (0.162) × φ) <ΔG ′ is preferable, 0.0150 × exp (0.162 × φ) <ΔG ′ is more preferable, and 0.0200 × exp (0.162 × φ) <ΔG ′ is more preferable.

  The Payne effect ΔG ′ calculated by the viscoelasticity test of the conjugated diene polymer composition is (1) dispersing a silica inorganic filler in a solution in which the conjugated diene polymer is dissolved (Step (A)), 2) In the dispersion step (A), the silica-based inorganic filler is dispersed in the polymer solution by sufficiently stirring using a wet medium stirring mill such as a bead mill to obtain the relationship of the formula (I) It is possible to control to satisfy In order to make ΔG ′ smaller, (3) in the dispersion step (A), a suitable dispersant is used in combination, and / or (4) water is used in the solvent removal step in the step (C). Preferably not. (3) By adding a dispersant in the dispersion step (A), reaggregation of the silica-based inorganic filler can be suppressed, the dispersibility can be improved, and ΔG ′ can be reduced. Although the decrease in ΔG ′ can often be confirmed by adding 1 to 50 parts by mass of the dispersant to 100 parts by mass of the silica-based inorganic filler, it depends on the types of the dispersant and the silica-based inorganic filler. In order to make the decrease of .DELTA.G 'remarkable, it is general to add a dispersant of about 8 to 30% by mass. On the other hand, when water is added in (4) (C) solvent removal step, the dispersion form of the silica-based inorganic filler collapses and ΔG 'tends to rise, so it is preferable to adopt the solvent removal method not using water .

The range of the volume fraction (φ) of the silica-based inorganic filler is not particularly limited as long as the content is in the range satisfying 5 to 150 parts by mass with respect to 100 parts by mass of the conjugated diene-based polymer. From the viewpoint of controlling the current value in the step (C) in an appropriate range while sufficiently exhibiting the reinforcing effect of the conjugated diene polymer composition by the inorganic filler, the amount is preferably 0.5 to 50 vol%, more preferably 1 It is preferably from 0 to 45 vol%, more preferably from 1.5 to 40 vol%.
The conjugated diene polymer composition satisfying the above formula (I) is in a state in which the silica based inorganic filler is finely dispersed in the polymer, and hence can be widely used in applications where the dispersibility of the silica based inorganic filler is required It is.

〔Master Badge〕
The masterbatch of the present embodiment contains the conjugated diene polymer composition of the present embodiment described above.
That is, the masterbatch of the present embodiment contains the components of the conjugated diene composition of the present embodiment, and is configured for the purpose of achieving convenience in the process of producing an object, for example, a rubber material, etc. Components, for example, those rich in silica-based inorganic filler may be contained, and in addition to the essential components of the conjugated diene-based composition of the present embodiment, oils, conjugated diene-based polymers, etc. are further blended. It may be done.
When the conjugated diene polymer composition of the present embodiment satisfying the formula (I) is used as a silica master batch as a tire raw material, the dispersibility of the silica based inorganic filler in the vulcanized product is improved, so that the rolling resistance and the wet skid Balance of resistance improves. Furthermore, it is excellent in abrasion resistance, tensile properties and processability.

[Use]
The conjugated diene-based polymer composition of the present embodiment can be compression molded into a cuboid referred to in the art as a veil, and can be applied to various applications. In addition, the conjugated diene-based polymer composition is compounded with other rubber materials such as natural rubber, silica-based inorganic fillers, inorganic materials such as carbon, etc., to be used for tire members, various industrial belts, etc. It can be processed.

[Rubber composition and molded article thereof]
The conjugated diene-based polymer composition of this embodiment and the masterbatch are, in addition to the various components described above, a rubber composition having a desired function by blending other components as necessary, and molding thereof It can be a body.

(Rubber component)
The conjugated diene polymer composition of the present embodiment is suitably used as a vulcanized product.
The vulcanized product includes, for example, the conjugated diene-based polymer composition or masterbatch of the present embodiment, if necessary, a silica-based inorganic filler, an organic filler such as carbon black, and the composition of the present embodiment Obtained by mixing with a rubbery polymer other than a rubber component, a silane coupling agent, a softener for rubber, a vulcanizing agent, a vulcanization accelerator, an auxiliary agent, etc. to form a composition, and then heating and vulcanizing it. be able to.

The conjugated diene polymer composition of the present embodiment can be used as a masterbatch for the production of rubber products such as tires.
For example, when preparing a rubber composition for a tire, a masterbatch having a silica content larger than that of the desired product is produced in consideration of the silica content in the tire and the content of the rubber component. The composition for a tire can be prepared by kneading the silica masterbatch and other rubber components such as natural rubber as required.
In the conventional tire rubber composition, the rubber component and the silica-based inorganic filler were melt-kneaded, but because of the hydrophilic group on the silica surface, the rubber component and the silica-based inorganic filler are difficult to be compatible with each other, and the dispersibility is It was difficult to raise it. On the other hand, when the master batch of this embodiment is used, the silica-based inorganic filler is finely dispersed in advance in the conjugated diene-based polymer, so silica can be used in the target composition mixed with other rubber components. The system inorganic filler tends to be finely dispersed. Therefore, when made into a vulcanizate, it has excellent balance between low hysteresis loss and wet skid resistance, has practically sufficient abrasion resistance and breaking strength, and can impart excellent processability.

When the masterbatch composition of the present embodiment is used for tires, automobile parts such as vibration-proof rubber, and vulcanized rubber applications such as shoes, it may further contain a silica-based inorganic filler as needed.
In this case, the (additionally added) inorganic filler other than that contained in the silica masterbatch is melt-kneaded with the masterbatch and the other rubber components. The added inorganic filler is assumed to be in a less dispersed state as compared to the dispersibility of the silica master batch, but the target substance is derived from the dispersibility of the silica based inorganic filler derived from the silica master batch. It is possible to improve the dispersibility. In addition, when the target composition contains a plurality of silica-based inorganic fillers, (1) a plurality of silica-based inorganic fillers may be added to the silica master batch, or (2) the particle size or surface A silica-based inorganic filler that is less likely to be dispersed in rubber due to the influence of conditions etc. may be blended into the silica master batch, and the other fillers may be melt-kneaded.

The masterbatch of the present embodiment may further contain a rubbery polymer other than the conjugated diene polymer. Such a rubbery polymer is not particularly limited, and, for example, a conjugated diene polymer or a hydrogenated product thereof, a random copolymer of a conjugated diene compound and a vinyl aromatic compound or a hydrogenated product thereof, a conjugated diene A block copolymer of a base compound and a vinyl aromatic compound or a hydrogenated product thereof, a non-diene polymer, a natural rubber and the like can be mentioned.
Specifically, butadiene rubber or a hydrogenated product thereof, isoprene rubber or a hydrogenated product thereof, styrene-butadiene rubber or a hydrogenated product thereof, styrene-butadiene block copolymer or a hydrogenated product thereof, styrene-isoprene block copolymer Styrene-based elastomers such as combined or hydrogenated products thereof, acrylonitrile-butadiene rubber or hydrogenated products thereof, etc. may be mentioned.
Also, as non-diene polymers, olefin-based elastomers such as ethylene-propylene rubber, ethylene-propylene-diene rubber, ethylene-butene-diene rubber, ethylene-butene rubber, ethylene-hexene rubber, ethylene-octene rubber, butyl rubber, brominated butyl rubber, Acrylic rubber, fluororubber, silicone rubber, chlorinated polyethylene rubber, epichlorohydrin rubber, α, β-unsaturated nitrile-acrylic acid ester-conjugated diene copolymer rubber, urethane rubber, polysulfide rubber and the like can be mentioned.
The various rubbery polymers described above may be modified rubbers having a functional group having polarity such as a hydroxyl group or an amino group. The weight average molecular weight is preferably 2,000 to 2,000,000, and more preferably 5,000 to 1,500,000, from the viewpoint of the balance between performance and processing characteristics. In addition, low molecular weight so-called liquid rubber can also be used. These rubbery polymers may be used alone or in combination of two or more.

<Other silica-based inorganic fillers>
When other silica-based inorganic fillers are further contained in addition to the silica-based inorganic filler contained in the master batch of the present embodiment, the blending ratio (mass ratio) of these is the silica-based inorganic material derived from the master batch It is preferable that a total of 5 to 300 parts by mass of the filler and the above-described other silica-based inorganic filler is contained, more preferably 10 to 250 parts by mass, and still more preferably 20 to 200 parts by mass. From the viewpoint of expression of the addition effect of the inorganic filler, the total amount of the silica-based inorganic filler derived from the masterbatch and the additional silica-based inorganic filler is preferably 5 parts by mass or more, and the processability of the composition And from the viewpoint of making the mechanical strength practically sufficient, the amount is preferably 300 parts by mass or less.

<Carbon black>
The conjugated diene polymer composition or the master batch in the present embodiment may contain carbon black.
It does not specifically limit as carbon black, For example, carbon black of each class, such as SRF, FEF, HAF, ISAF, and SAF, can be used. Among these, carbon black having a nitrogen adsorption specific surface area of 50 m ² / g or more and a dibutyl phthalate (DBP) oil absorption of 80 mL / 100 g is preferable.
The content of carbon black is preferably 0.5 to 100 parts by mass with respect to 100 parts by mass of a rubber component containing a conjugated diene-based polymer component derived from the conjugated diene-based polymer composition or masterbatch of the present embodiment, 3-100 mass parts is more preferable, and 5-50 mass parts is further more preferable. The content of carbon black is preferably 0.5 parts by mass or more from the viewpoint of developing performance required for applications such as tires such as dry grip performance and conductivity, and from the viewpoint of dispersibility, 100 parts by mass It is preferable to set it as the following.

<Other filler>
In addition to the silica-based inorganic filler and the carbon black, the conjugated diene-based polymer composition of the present embodiment may contain metal oxides and metal hydroxides as other fillers.
A metal oxide is a solid particle having a chemical formula MxOy (M represents a metal atom, and x and y each represent an integer of 1 to 6) as the main component of the constituent unit, for example, alumina, titanium oxide , Magnesium oxide, zinc oxide and the like can be used.
A mixture of metal oxides and inorganic fillers other than metal oxides can also be used. The metal hydroxide is not particularly limited, and examples thereof include aluminum hydroxide, magnesium hydroxide, zirconium hydroxide and the like.

<Silane coupling agent>
The conjugated diene polymer composition of the present embodiment may contain a silane coupling agent.
The silane coupling agent has a function to intimate the interaction between the rubber component and the silica-based inorganic filler, and has a group having affinity or binding property to each of the rubber component and the silica-based inorganic filler. In general, a compound having a sulfur bonding moiety, an alkoxysilyl group and a silanol group moiety in one molecule is used. Specifically, bis- [3- (triethoxysilyl) -propyl] -tetrasulfide, bis- [3- (triethoxysilyl) -propyl] -disulfide, bis- [2- (triethoxysilyl) -ethyl ]-Tetrasulfide etc. are mentioned.
The content of the silane coupling agent is 0.1 to 30 with respect to a total of 100 parts by mass of the silica-based inorganic filler derived from the conjugated diene-based polymer composition and the additional silica-based inorganic filler to be added. A mass part is preferable, 0.5-20 mass parts is more preferable, 1-15 mass parts is more preferable. When a silane coupling agent is used in the production process of the masterbatch, it is preferable that the total amount with the amount of the coupling agent derived from the masterbatch is in the above range. The said addition effect by a silane coupling agent can be made further remarkable as the compounding quantity of a silane coupling agent is the said range.

<Softener for rubber>
Even if the conjugated diene polymer composition or the master batch in the present embodiment further includes a softener for rubber other than the timing at which the step (B) described above is performed in order to improve the processability. Good.
As a softener for rubber, a mineral oil, or a liquid or low molecular weight synthetic softener is suitable. Softeners for mineral oil-based rubbers called process oils or extender oils, which are used to soften, increase the volume, and improve the processability of rubber, are a mixture of aromatic rings, naphthenic rings, and paraffin chains, A paraffin chain whose carbon number accounts for 50% or more of the total carbon is called paraffinic, a naphthenic ring having a carbon number of 30 to 45% is a naphthene, and an aromatic carbon number exceeding 30% is an aromatic It is called a system. As a softener for rubber to be used together with the masterbatch of the present embodiment, one having an appropriate aromatic content is preferable because it tends to be compatible with the copolymer.
The compounding amount of the softener for rubber is preferably 0 to 100 parts by mass with respect to 100 parts by mass of the rubber component containing the conjugated diene-based polymer derived from the conjugated diene-based polymer composition or masterbatch of the present embodiment. 5 to 80 parts by mass is more preferable, and 10 to 50 parts by mass is further preferable. When a softener for rubber is added in the process of producing the conjugated diene polymer composition or masterbatch of the present embodiment, the total amount with the softener for rubber derived therefrom is preferably within the above range. When the content of the softener for rubber is 100 parts by mass or less with respect to 100 parts by mass of the rubber component, the occurrence of bleed out can be prevented, and the occurrence of stickiness on the surface of the composition can be prevented.

<Kneading method>
Additives such as conjugated diene polymer composition or master batch of the present embodiment, other rubbery polymer, silica based inorganic filler, carbon black and other fillers, silane coupling agent, softener for rubber It does not specifically limit about the method to mix and.
For example, a melt-kneading method using a general mixing machine such as an open roll, a Banbury mixer, a kneader, a single screw extruder, a twin screw extruder, a multiple screw extruder, etc. Methods such as heating and removing can be mentioned. Among these, a melt-kneading method using a roll, a Banbury mixer, a kneader or an extruder is preferable from the viewpoint of productivity and good kneadability. Further, any of a method of kneading the master batch and various compounding agents at once, and a method of dividing and mixing into a plurality of times can be applied.

<Vulcanization composition>
The conjugated diene polymer composition of the present embodiment may be a vulcanized composition which has been vulcanized with a vulcanizing agent.
Examples of the vulcanizing agent include, but are not limited to, radical generators such as organic peroxides and azo compounds, oxime compounds, nitroso compounds, polyamine compounds, sulfur and sulfur compounds. Sulfur compounds include sulfur monochloride, sulfur dichloride, disulfide compounds, high molecular weight polysulfur compounds and the like.
The amount of the vulcanizing agent used is usually 0.01 to 20 parts by mass with respect to 100 parts by mass of the rubber component containing the conjugated diene based polymer derived from the conjugated diene based polymer composition of the present embodiment, 0.1 to 15 parts by mass is preferable. As the vulcanization method, conventionally known methods can be applied, and the vulcanization temperature is usually 120 to 200 ° C., preferably 140 to 180 ° C.
In addition, at the time of vulcanization, a vulcanization accelerator may be used as necessary. As the vulcanization accelerator, conventionally known materials can be used, and it is not limited to the following. For example, sulfenamide type, guanidine type, thiuram type, aldehyde-amine type, aldehyde-ammonia type, There may be mentioned vulcanization accelerators such as thiazoles, thioureas and dithiocarbamates.
In addition, as a curing assistant, zinc flower, stearic acid and the like can be used. The amount of the vulcanization accelerator used is usually 0.01 to 20 parts by mass with respect to 100 parts by mass of the rubber component containing the conjugated diene-based polymer derived from the composition of the present embodiment, and 0.1 to 20 parts by mass 15 parts by mass is preferred.

  In the conjugated diene polymer composition of the present embodiment, other softeners and fillers other than those described above, a heat stabilizer, an antistatic agent, weathering stability, and so forth, as long as the object of the present embodiment is not impaired. Various additives such as an agent, an anti-aging agent, a coloring agent, and a lubricant may be used. As other softeners, known softeners can be used. Specific examples of the other fillers include calcium carbonate, magnesium carbonate, aluminum sulfate and barium sulfate. A well-known material can be used as said heat resistant stabilizer, an antistatic agent, a weathering stabilizer, an antiaging agent, a coloring agent, and a lubricant, respectively.

Next, the present embodiment will be described in more detail by way of specific examples and comparative examples, but the present embodiment is not limited at all by the following examples as long as the gist thereof is not exceeded.
The evaluation method of the various characteristics in an Example and a comparative example is as follows.

(Evaluation 1) Amount of bound styrene 100 mg of each of Samples B, D, F and H of Production Examples 1 to 4 described later was dissolved in 100 mL with chloroform, and dissolved to obtain a measurement sample.
The amount (% by mass) of bound styrene was measured by absorption at UV 254 nm by the phenyl group of styrene (manufactured by Shimadzu Corporation, spectrophotometer “UV-2450”).

(Evaluation 2) Microstructure of butadiene moiety (1,2-vinyl bond content)
50 mg of samples B, D, F, and H of Production Examples 1 to 4 described later were dissolved in 10 mL of carbon disulfide to obtain a measurement sample.
Using a solution cell, the infrared spectrum was measured in the range of 600 to 1000 cm ^-1 , and the microstructure of the butadiene portion was determined according to the formula of Hampton's method by absorbance at a predetermined wave number (Fourier Transform Red Outer spectrophotometer "FT-IR 230").

(Evaluation 3) Before modification and before modification Mooney viscosity Using Mooney viscometer ("VR1132" manufactured by Ueshima Seisakusho Co., Ltd.), in accordance with JIS K 6300 (ISO 289-1), before modification and modification in Production Examples 1 to 4 described later The subsequent Mooney viscosity was measured.
The measurement temperature was 110 ° C. before denaturation and 100 ° C. after denaturation.
First, the sample was preheated for 1 minute, and then the rotor was rotated at 2 rpm, and the torque after 4 minutes was measured to obtain Mooney viscosity (ML _{1 +4} ).

(Evaluation 4) Average particle size of silica-based inorganic filler (median diameter)
The average particle diameter (median diameter) of the silica-based inorganic filler in the dispersion was measured using a laser diffraction particle size distribution diameter (Partica LA-950, manufactured by Horiba, Ltd.).
The dispersion was diluted with cyclohexane to a solid concentration of about 1%, adjusted until the permeability was between the recommended levels of 85% and 95%, treated with ultrasound for 1 minute, and introduced into the measuring cell.
The refractive index for calculation was 1.427 for cyclohexane, and the wavelength dependency was considered for the silica-based inorganic filler, (R) used 1.457 and (B) used 1.470.

(Evaluation 5) Volume fraction of silica-based inorganic filler in masterbatch φ (vol%)
Using a TG-DTA (manufactured by Hitachi High-Tech Science Co., Ltd., differential thermal thermal simultaneous measurement device STA7200RV) as a measuring device, place the master batch W (g) in an aluminum pan with an outer diameter of 5.0 mm, 25 ° C to 500 ° C Heat at a heating rate of up to 20 ° C / min and hold at 500 ° C for 25 minutes in order to remove the flammable components contained in the masterbatch, and confirm that the mass change is constant, with residue The mass W _S (g) of a certain silica-based inorganic filler was measured.
Furthermore, the mass W _D (g) of the dispersant was calculated from the charge amount ratio with the silica-based inorganic filler, and the mass W _P (g) of the polymer was calculated from the difference from W (g).
The specific gravity of the silica-based inorganic filler, dispersant, and polymer is d _S (g / cm ³ ), d _D (g / cm ³ ) and d _P (g / cm ³ ), respectively, according to the following equation in the masterbatch The volume fraction φ (vol%) of the silica-based inorganic filler was calculated.
φ = (W _S / d _S ) / [(W _S / d _S ) + (W _D / d _D ) + (W _P / d _P )] × 100

(Evaluation 6) Payne effect Storage viscoelasticity (0.07% strain and 1200% strain) measured according to ASTM D6204 using RPA 2000 (manufactured by ALPHA TECHNOLOGIES, unvulcanized visco-elastic device) as a measuring device The Payne effect ΔG ′ (MPa) was measured as the difference in value).

(Condition 1) Internal volume (V ₀ ) of the degassing apparatus
The internal volume (V ₀ ) of the volatilization apparatus in Examples and Comparative Examples represents the internal volume (L) of the volatilization apparatus, and does not include the volumes of the screw portion and the device jacket portion. Specifically, while the screw is installed, water is introduced into the apparatus with all the piping and equipment connections, such as the vent piping and feed connected to the apparatus, the raw material feed piping, and the polymer discharge piping, closed. the amount of water was put until the liquid was set to V _0.

[Production example: conjugated diene polymer]
(Production Example 1)
With an internal volume of 10 L, an internal height-to-diameter ratio (L / D) of 4, an inlet at the bottom, an outlet at the top, two autoclaves connected in series with a stirrer and a jacket for temperature control The first group is a polymerization reactor, and the second group is a modification reactor.
The mixture was previously mixed with 16.0 g / min of 1,3-butadiene, 8.0 g / min of styrene and 136.0 g / min of n-hexane, from which impurities such as water and the like were removed. Immediately before this mixed solution enters the first reactor, n-butyllithium for impurity inactivation treatment is mixed with a static mixer at 0.056 mmol / min, and then continuously in the bottom of the first reactor. Supplied to Furthermore, in a first group reactor of 2,2-bis (2-oxolanyl) propane as a polar substance at a rate of 0.020 g / min and n-butyllithium as a polymerization initiator at a rate of 0.150 mmol / min. It was supplied to the bottom, and the polymerization reaction was continued so that the internal temperature of the reactor outlet became 80 ° C. From the outlet of the first reactor, a small amount of the polymer solution before adding the modifier is taken out, and after adding the antioxidant (BHT) to 0.2 g per 100 g of the polymer, the solvent is removed and the Mooney viscosity is 110 ° C. As a result of measuring, it was 52. The temperature of the second reactor was kept at 85 ° C., and tetraglycidyl-1,3-bisaminomethylcyclohexane (TGAMH) as a modifier was added from the bottom of the second reactor at a rate of 0.038 mmol / min. , Modified (coupling) reaction was performed. Antioxidant (BHT) was continuously added to the polymer solution flowing out from the top of the second reactor at 0.048 g / min (n-hexane solution) to a concentration of 0.2 g per 100 g of polymer The reaction was terminated to obtain a 15% by mass solution (sample A) of the modified conjugated diene polymer.
Furthermore, the solvent was removed from the sample A by steam stripping, and then the sample A was subjected to a drying treatment with a drier to obtain a solid (sample B) of the modified conjugated diene polymer.
Properties of sample A and sample B are shown in Table 1.

(Production Example 2)
The modifier was changed from tetraglycidyl-1,3-bisaminomethylcyclohexane to 2,2-dimethoxy-1- (3-trimethoxysilylpropyl) -1-aza-2-silacyclopentane (AS-1). The other conditions were the same as in (Production Example 1) to obtain a 15% by mass solution (Sample C) of the modified conjugated diene polymer and a solid (Sample D) of the modified conjugated diene polymer. Properties of sample B and sample D are shown in Table 1.

(Production Example 3)
The modifier was changed from tetraglycidyl-1,3-bisaminomethylcyclohexane to N-n-butyl-aza-2,2-dimethoxysilacyclopentane (AS-2). The other conditions were the same as in (Production Example 1) to obtain a 15% by mass solution (Sample E) of the modified conjugated diene polymer and a solid (Sample F) of the modified conjugated diene polymer.
The properties of Sample E and Sample F are shown in Table 1.

(Production Example 4)
The rate of the polar substance 2,2-bis (2-oxolanyl) propane fed to the bottom of the first reactor was 0.010 g / min, and the rate of n-butyllithium as the polymerization initiator was 0.075 mmol / min. Further, a 15% by mass solution of a conjugated diene polymer (sample G) and a solid of a conjugated diene polymer (sample H) were prepared in the same manner as in (Production Example 1) except that no modifier was used. Obtained.
The properties of Sample G and Sample H are shown in Table 1.

〔Master Badge〕
Example 1 Composition (M1)
15.4 kg of cyclohexane was added to and diluted with 15.4 kg of sample A, and 438.8 g of a silica-based inorganic filler and 87.8 g of n-octyltriethoxysilane as a dispersant (1) were added and stirred at 10000 rpm × 5 minutes with a homogenizer And suspended. Here, the blending composition ratio was 75 parts by mass of the silica-based inorganic filler and 15 parts by mass of the dispersant (1) with respect to 100 parts by mass of the modified conjugated diene-based polymer contained in the sample A. This solution is treated with a bead mill (UAM-05 manufactured by Hiroshima Metal & Machinery Co., Ltd., UAM-05) filled with 0.5 mm zirconia beads at a feed rate of 17.0 kg / h and a circumferential speed of 10 m / s for 6 hours, and then The beads were changed to 0.1 mm, and the liquid was treated at a displacement of 17.0 kg / h and a peripheral speed of 12 m / s for 6 hours to obtain a dispersion. The average particle diameter (median diameter) of the silica-based inorganic filler in the dispersion was 520 nm.
Next, this dispersion was subjected to a twin screw type kneader with a screw diameter (D) of 50 mm, a ratio of screw length (L) to screw diameter (D) (L / D) = 6.0, and V ₀ = 4.0. The solution was continuously supplied at a rate of 0.83 kg / min from the supply port. At this time, the screw rotational speed and the rotational direction as viewed from the motor drive part were 50 rpm in the counterclockwise direction on one side and 100 rpm in the clockwise direction on the other side. The motor current value was I ₀ = 7.9 A before the sample was supplied, and I ₁ = 12.0 A and I ₁ / I ₀ = 1.52 after the sample was supplied. The current was AC at a frequency of 60 Hz. The dispersion was heated while supplying 180 ° C. heat medium oil to the kneader jacket. The vent port was connected to a vacuum pump through piping to keep the inside of the apparatus at 100 torr. The dispersion was concentrated while being conveyed by a screw, and finally discharged from a small extruder connected to the upper surface of the tip of the kneader to obtain a solid composition (M1). The vaporized solvent passed through the vent and was condensed by a condenser cooled to 7 ° C. placed in front of the vacuum pump and recovered as a liquid. The volume fraction φ of the silica-based inorganic filler in the composition (M1) was 23.6 vol%, and the Payne effect ΔG ′ was 2.3 MPa.

Example 2 Composition (M2)
A solid composition (M2) was obtained in the same manner as in Example 1 except that sample C was used instead of sample A.
Here, the average particle diameter (median diameter) of the silica-based inorganic filler in the dispersion liquid was 490 nm, and the current value of the devolatilizer was I ₁ = 11.9 A and I ₁ / I ₀ = 1.51. The volume fraction φ of the silica-based inorganic filler in the composition (M2) was 23.6 vol%, and the Payne effect ΔG ′ was 1.8 MPa.

Example 3 Composition (M3)
A solid composition (M3) was obtained in the same manner as in Example 1 except that sample E was used instead of sample A.
Here, the average particle diameter (median diameter) of the silica-based inorganic filler in the dispersion was 550 nm, and the current value of the devolatilizer was I ₁ = 12.3 A and I ₁ / I ₀ = 1.56. The volume fraction φ of the silica-based inorganic filler in the composition (M3) was 23.6 vol%, and the Payne effect ΔG ′ was 2.0 MPa.

Example 4 Composition (M4)
A solid composition (M4) was obtained in the same manner as in Example 1 except that sample G was used instead of sample A.
Here, the average particle diameter (median diameter) of the silica-based inorganic filler in the dispersion liquid is 620 nm, and the current value of the degassing apparatus is I ₁ / I ₀ = 1.59 at I ₁ = 12.6 A. The volume fraction φ of the silica-based inorganic filler in the composition (M4) was 23.6 vol%, and the Payne effect ΔG ′ was 3.4 MPa.

Example 5 Composition (M5)
The dispersant was replaced with 87.8 g of n-octyltriethoxysilane, 52.7 g of n-octyltriethoxysilane as the dispersant (1), and NXT-Z 45 (made by Momentive) as the dispersant (2). A solid composition (M5) was obtained in the same manner as in Example 1 except that .1 g was used.
The average particle size of the silica-based inorganic filler in the dispersion (median diameter) 500 nm, the current value of the devolatilizer was I ₁ / I ₀ = 1.52 in I ₁ = 12.0A. The volume fraction φ of the silica-based inorganic filler in the composition (M5) was 23.6 vol%, and the Payne effect ΔG ′ was 2.2 MPa.

Example 6 Composition (M6)
The dispersant was replaced with 87.8 g of n-octyltriethoxysilane, 52.7 g of n-octyltriethoxysilane as the dispersant (1), and NXT-Z 45 (made by Momentive) as the dispersant (2). A solid composition (M6) was obtained in the same manner as in Example 2 except that .1 g was used.
Here, the average particle diameter (median diameter) of the silica-based inorganic filler in the dispersion was 510 nm, and the current value of the devolatilizer was I ₁ / I ₀ = 1.48 at I ₁ = 11.8 A. The volume fraction φ of the silica-based inorganic filler in the composition (M6) was 23.6 vol%, and the Payne effect ΔG ′ was 2.2 MPa.

Example 7 Composition (M7)
A solid was obtained in the same manner as in Example 1 except that 87.8 g of NXT-Z45 (manufactured by Momentive) as the dispersant (2) was used instead of 87.8 g of n-octyltriethoxysilane as the dispersant. A composition (M7) was obtained.
The average particle size of the silica-based inorganic filler in the dispersion (median diameter) 500 nm, the current value of the devolatilizer was I ₁ / I ₀ = 1.67 in I ₁ = 13.2A. The volume fraction φ of the silica-based inorganic filler in the composition (M7) was 23.6 vol%, and the Payne effect ΔG ′ was 1.9 MPa.

Example 8 Composition (M8)
A solid was obtained in the same manner as in Example 2 except that 87.8 g of NXT-Z45 (manufactured by Momentive), which is the dispersant (2), was used instead of 87.8 g of n-octyltriethoxysilane as the dispersant. A composition (M8) was obtained.
Here, the average particle diameter (median diameter) of the silica-based inorganic filler in the dispersion liquid is 480 nm, and the current value of the degassing apparatus is I ₁ / I ₀ = 1.70 at I ₁ = 13.4 A. The volume fraction φ of the silica-based inorganic filler in the composition (M7) was 23.6 vol%, and the Payne effect ΔG ′ was 1.1 MPa.

Example 9 Composition (M9)
A solid composition (M9) was obtained in the same manner as in Example 1 except that the dispersant was not used.
Here, the average particle diameter (median diameter) of the silica-based inorganic filler in the dispersion is 3.4 μm, and the current value of the devolatilizer is I ₁ = 15.6 A and I ₁ / I ₀ = 1.97. The The volume fraction φ of the silica-based inorganic filler in the composition (M9) was 26.0 vol%, and the Payne effect ΔG ′ was 16.0 MPa.

Example 10 Composition (M10)
A solid composition (M10) was obtained in the same manner as in Example 6 except that the dispersant was not used.
Here, the average particle diameter (median diameter) of the silica-based inorganic filler in the dispersion is 2.7 μm, and the current value of the devolatilizer is I ₁ = 15.2 A and I ₁ / I ₀ = 1.92. The The volume fraction φ of the silica-based inorganic filler in the composition (M10) was 26.0 vol%, and the Payne effect ΔG ′ was 15.5 MPa.

Example 11 Composition (M11)
A solid composition (M11) is obtained in the same manner as in Example 1 except that 585.0 g of the silica-based inorganic filler and 117.0 g of n-octyltriethoxysilane as the dispersant (1) are used. The
Here, the average particle diameter (median diameter) of the silica-based inorganic filler in the dispersion liquid is 530 nm, and the current value of the degassing apparatus is I ₁ / I ₀ = 1.92 at I ₁ = 15.2A. The volume fraction φ of the silica-based inorganic filler in the composition (M11) was 31.9 vol%, and the Payne effect ΔG ′ was 16.5 MPa.

Example 12 Composition (M12)
A solid composition (M12) is obtained in the same manner as in Example 2 except that 585.0 g of the silica-based inorganic filler and 117.0 g of n-octyltriethoxysilane as the dispersant (1) are used. The
Here, the average particle diameter (median diameter) of the silica-based inorganic filler in the dispersion liquid was 490 nm, and the current value of the degassing apparatus was I ₁ / I ₀ = 1.90 at I ₁ = 15.0 A. The volume fraction φ of the silica-based inorganic filler in the composition (M12) was 31.9 vol%, and the Payne effect ΔG ′ was 15.1 MPa.

Example 13 Composition (M13)
A solid composition (M13) was obtained in the same manner as in Example 1 except that the amount of the silica-based inorganic filler was changed to 292.5 g, and the dispersant (1), n-octyltriethoxysilane, was changed to 58.5 g. The
Here, the average particle diameter (median diameter) of the silica-based inorganic filler in the dispersion liquid is 530 nm, and the current value of the devolatilizer is I ₁ = 10.2 A and I ₁ / I ₀ = 1.29. The volume fraction φ of the silica-based inorganic filler in the composition (M13) was 19.0 vol%, and the Payne effect ΔG ′ was 1.3 MPa.

Example 14 Composition (M14)
A solid composition (M14) was obtained in the same manner as in Example 2 except that the silica-based inorganic filler was changed to 292.5 g and the dispersant (1) to n-octyltriethoxysilane was changed to 58.5 g. The
Here, the average particle diameter (median diameter) of the silica-based inorganic filler in the dispersion was 500 nm, and the current value of the devolatilizer was I ₁ /9.8 and I ₁ / I ₀ = 1.24. The volume fraction φ of the silica-based inorganic filler in the composition (M14) was 19.0 vol%, and the Payne effect ΔG ′ was 0.8 MPa.

Example 15 Composition (M15)
A solid was obtained in the same manner as in Example 1 except that 35.1 g of Dispersant (2) NXT-Z 45 (manufactured by Momentive) was used instead of 87.8 g of n-octyltriethoxysilane as the dispersant. A composition (M15) was obtained.
Here, the average particle diameter (median diameter) of the silica-based inorganic filler in the dispersion liquid was 490 nm, and the current value of the degassing apparatus was I ₁ / I ₀ = 1.54 at I ₁ = 12.2 A. The volume fraction φ of the silica-based inorganic filler in the composition (M15) was 25.0 vol%, and the Payne effect ΔG ′ was 4.5 MPa.

Example 16 Composition (M16)
A solid was obtained in the same manner as in Example 2, except that 35.1 g of NXT-Z45 (manufactured by Momentive), which is the dispersant (2), was used instead of 87.8 g of n-octyltriethoxysilane as the dispersant. A composition (M16) was obtained.
The average particle size of the silica-based inorganic filler in the dispersion (median diameter) 480 nm, the current value of the devolatilizer was I ₁ / I ₀ = 1.53 in I ₁ = 12.1A. The volume fraction φ of the silica-based inorganic filler in the composition (M16) was 25.0 vol%, and the Payne effect ΔG ′ was 3.3 MPa.

Example 17 Composition (M17)
A solid composition (M11) was obtained in the same manner as in Example 1 except that the dispersion liquid was subjected to steam stripping and drying using a roll after devolatilization using a twin-screw kneader.
The volume fraction φ of the silica-based inorganic filler in the composition (M17) was 23.6 vol%, and the Payne effect ΔG ′ was 10.8 MPa.

Example 18 Composition (M18)
A solid composition (M18) was obtained in the same manner as in Example 2 except that the dispersion liquid was subjected to steam stripping and drying using a roll after devolatilization using a twin-screw kneader.
The volume fraction φ of the silica-based inorganic filler in the composition (M18) was 23.6 vol%, and the Payne effect ΔG ′ was 10.6 MPa.

Comparative Example 1 Composition (M19)
100 parts by mass of sample (B) is added to a Banbury type laboplast mill (volume 250 cc manufactured by Toyo Seiki Co., Ltd.) preheated to 180 ° C. and masticated at 50 rpm for 3 minutes, then 75 parts by mass of silica based inorganic filler The kneading was started at a rotation speed of 50 rpm.
After the internal temperature reached 150 ° C., kneading was continued for 2 minutes while adjusting the rotation speed so as not to exceed 160 ° C., and the mixture was discharged to obtain a composition (M19).
The volume fraction φ of the silica-based inorganic filler in the composition (M19) was 26.0 vol%, and the Payne effect ΔG ′ was 32.3 MPa.

Comparative Example 2 Composition (M20)
A composition (M20) was obtained in the same manner as in Comparative Example 1 except that the sample (D) was used instead of the sample (B).
The volume fraction φ of the silica-based inorganic filler in the composition (M20) was 26.0 vol%, and the Payne effect ΔG ′ was 29.9 MPa.

Comparative Example 3 Composition (M21)
A composition (M21) was obtained in the same manner as in Comparative Example 1 except that the sample (F) was used instead of the sample (B).
The volume fraction φ of the silica-based inorganic filler in the composition (M21) was 26.0 vol%, and the Payne effect ΔG ′ was 32.0 MPa.

Comparative Example 4 Composition (M22)
A composition (M22) was obtained in the same manner as in Comparative Example 1 except that the sample (H) was used instead of the sample (B).
The volume fraction φ of the silica-based inorganic filler in the composition (M22) was 26.0 vol%, and the Payne effect ΔG ′ was 43.4 MPa.

The composition (parts by mass) of the compositions of Examples 1 to 18 and Comparative Examples 1 to 4, the volume fraction φ of the silica-based inorganic filler in the composition, and the Payne effect ΔG ′ are shown in Tables 2 and 3. .
In Table 2 and Table 3, the solvent removal conditions (two-screw extrusion) mean "solvent removal operation using a twin-screw extruder", and (steam) is "solvent removal operation by steam stripping" Means

[Examples 19 to 36, Comparative Examples 5 to 12]
Using the samples and reagents shown in Table 4 and Table 5, rubber compositions containing the respective samples were obtained according to the conditions shown below.
Composition samples (M1 to M22): In order to unify the content of the silica-based inorganic filler in all the samples, the silica-based inorganic filler derived from the masterbatch sample is based on 100 parts by weight of the (modified) conjugated diene-based polymer It was determined to be 75 parts by mass.
(Modified) conjugated diene polymer (samples B, D, F, H): 100 parts by mass (only comparative examples 9 to 12)
Silica based inorganic filler (trade name "Ultrasil 7000GR" nitrogen adsorption specific surface area 170 m2 / g manufactured by Evonik Degussa): 75.0 parts by mass Silane coupling agent: trade name "NXT-Z45" manufactured by Momentive as a dispersant For masterbatch samples that used the sample, no silane coupling agent was added, assuming that they already have the effect as a coupling agent, and for samples that did not use “NXT-Z45”, Evonik Degussa Co., Ltd. 6.0 parts by mass of “Si75” (bis (triethoxysilylpropyl) disulfide) under the trade name of

In addition to the compositions shown in Tables 4 and 5, the following materials were added.
Carbon black (made by Tokai Carbon Co., Ltd., SEAST KH (N 339): 5.0 parts by mass S-RAE oil (trade name “Process NC 140” manufactured by JX Nippon Oil & Energy Co., Ltd.): 42.0 parts by mass .5 parts by mass stearic acid: 1.0 parts by mass Antiaging agent (N- (1,3-dimethylbutyl) -N'-phenyl-p-phenylenediamine): 2.0 parts by mass Sulfur: 2.2 parts by mass Vulcanization accelerator 1 (N-cyclohexyl-2-benzothiazylsulfinamide): 1.7 parts by mass Vulcanization accelerator 2 (diphenyl guanidine): 2.0 parts by mass in total: 239.4 to 259.4 parts by mass

The above materials were kneaded by the following method to obtain a rubber composition.
Using a closed kneader (internal capacity 0.3 L) equipped with a temperature control device, master batch samples (M1 to M22) under the conditions of a filling rate of 65% and a rotor rotational speed of 50/57 rpm as kneading in the first stage (Modified) conjugated diene polymer, silica inorganic filler, carbon black, silane coupling agent, S-RAE oil, zinc flower, stearic acid were kneaded.
At this time, the temperature of the closed mixer was controlled, and the discharge temperature was 155 to 160 ° C. to obtain a rubber composition (compound).
Next, as kneading of the second stage, after cooling the mixture obtained above to room temperature, an antiaging agent was added, and kneading was performed again.
Also in this case, the discharge temperature of the mixture was adjusted to 155 to 160 ° C. by temperature control of the mixer.
After cooling, sulfur and a vulcanization accelerator were added and kneaded with an open roll set at 70 ° C. as kneading in the third stage.
Thereafter, it was molded and vulcanized with a vulcanizing press at 160 ° C. for 20 minutes.
After vulcanization, the physical properties of the rubber composition were measured.
The physical property measurement results are shown in Table 4 and Table 5.

The physical properties of the rubber composition were measured by the following method.
((1) Formulation Mooney viscosity (blend Mooney viscosity))
A sample after mixing and adding sulfur and a vulcanization accelerator is used as a measurement target, and after preheating for 1 minute at 130 ° C. according to JIS K6300-1 using a Mooney viscometer, the rotor is The viscosity was measured after 4 minutes of rotation at 2 revolutions per minute.
The smaller the value, the better the processability.

((2) Breaking strength, breaking elongation)
The rubber composition after vulcanization was used as a measurement sample, measured according to the tensile test method of JIS K6251, and the result of Comparative Example 10 was indexed as 100.

((3) Viscoelastic parameter)
The vulcanized rubber composition was used as a measurement sample, and the visco-elastic parameter was measured in a torsion mode using a visco-elastic tester "ARES" manufactured by Rheometrics Scientific Co., Ltd.
Each measured value was indexed with the result of Comparative Example 10 as 100.
Tan δ measured at a frequency of 10 Hz and a strain of 1% at 0 ° C. was used as an index of wet grip performance (denoted as 0 ° C. tan δ (strain 1%) in Tables 4 and 5).
The larger the value, the better the wet grip performance.
In addition, tan δ measured at a frequency of 10 Hz and a strain of 3% at 50 ° C. was taken as an index of the fuel saving characteristics (in Table 4 and Table 5, it was described as 50 ° C. tan δ (strain 3%)).
The larger the value, the better the fuel saving performance.

((4) Wear resistance)
Using the rubber composition after vulcanization as a measurement sample, measure the amount of abrasion at a load of 44.1 N at 1000 revolutions according to JIS K 6264-2 using an Akron abrasion tester (manufactured by Yasuda Seiki Seisakusho Co., Ltd.) The result of Comparative Example 10 was indexed as 100.
The larger the index, the better the abrasion resistance.

As shown in Tables 4 and 5, the rubber compositions of Examples 19 to 36 have low tan δ at 50 ° C. as compared with the rubber composition of Comparative Example 10, and low rolling resistance of the tire is realized. At the same time, it was confirmed that the tan δ at 0 ° C. was high and the wet skid resistance was excellent.
Moreover, compared with the composition of Comparative Example 10, it was confirmed that the composition Mooney viscosity is low and the balance between the processability and the physical properties of the vulcanizate is excellent.
Furthermore, it has been confirmed that they have practically sufficient abrasion resistance and breaking strength.
From the above, the masterbatch and the rubber composition of this example are excellent in the balance between rolling resistance and wet skid resistance when made into a vulcanizate, and have sufficient abrasion resistance and fracture strength sufficient for practical use. It was also confirmed that the processability is excellent.

  The conjugated diene polymer composition of the present invention has industrial applicability as a material of a base tread for a tire and a tire.

Claims (10)

A conjugated diene-based polymer composition in which a silica-based inorganic filler is dispersed in a conjugated diene-based polymer,
A volume fraction φ (vol%) of the silica-based inorganic filler in the conjugated diene-based polymer composition,
Payne effect ΔG '(MPa) calculated by viscoelasticity test,
But,
The conjugated diene type polymer composition which satisfy | fills following formula (1).
ΔG ′ <0.250 × exp (0.162 × φ) (I)
(In the formula (I), ΔG ′ is the difference in storage elastic modulus (G ′) value when the 0.07% strain and the 1200% strain of the conjugated diene polymer composition are measured according to ASTM D 6204 Represents the Payne effect obtained as: φ represents the volume fraction (vol%) of the silica-based inorganic filler in the conjugated diene-based polymer composition.)   The conjugated diene-based polymer composition according to claim 1, further comprising 1 to 50 parts by mass, based on 100 parts by mass of the silica-based inorganic filler, of a dispersant.   The conjugated diene polymer composition according to claim 1 or 2, wherein the conjugated diene polymer is modified.   A masterbatch comprising the conjugated diene polymer composition according to any one of claims 1 to 3.   A tire member comprising the conjugated diene polymer composition according to any one of claims 1 to 3. A method for producing a conjugated diene polymer composition according to any one of claims 1 to 3, wherein the silica based inorganic filler is dispersed in a matrix of the conjugated diene polymer,
In the step (A), a silica-based inorganic filler is dispersed in a solution in which a conjugated diene-based polymer is dissolved to obtain a dispersion.
Desolvating the dispersion (C);
Have,
In the step (A), the silica-based inorganic filler is dispersed,
Method of producing a conjugated diene polymer composition. In the step (A), 1 to 50 parts by mass of a dispersant is added to the solution with respect to 100 parts by mass of the silica-based inorganic filler.
The manufacturing method of the conjugated diene type polymer composition of Claim 6. As a process before the said process (A),
Manufacturing a conjugated diene polymer and modifying the conjugated diene polymer,
The manufacturing method of the conjugated diene type polymer composition of Claim 6 or 7. In the step (C) of removing the solvent,
Heating the dispersion while conveying it to a device having a rotating twin screw,
The motor current value of the screw and the motor current value of the screw at no load condition satisfy the following formula (II):
A method for producing a conjugated diene polymer composition according to any one of claims 6 to 8.
1.05 ≦ ((I ₁ ) / (I ₀ )) ≦ 2.00 (II)
(In the formula (II), I ₁ represents the motor current value [A] of the screw in the step (C) of removing the solvent, and I ₀ represents the motor current value [A] of the screw at no load. Represent) As a step prior to the step (C) of removing the solvent from the dispersion,
Carrying out the step (B) of adding a conjugated diene polymer solution or an oil,
The manufacturing method of the conjugated diene type polymer composition as described in any one of Claims 6 thru | or 9.