CN112979876B - Branched conjugated diene polymer and method for producing same, method for producing rubber composition, and method for producing tire - Google Patents
Branched conjugated diene polymer and method for producing same, method for producing rubber composition, and method for producing tire Download PDFInfo
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- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F236/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, at least one having two or more carbon-to-carbon double bonds
- C08F236/02—Copolymers of compounds having one or more unsaturated aliphatic radicals, at least one having two or more carbon-to-carbon double bonds the radical having only two carbon-to-carbon double bonds
- C08F236/04—Copolymers of compounds having one or more unsaturated aliphatic radicals, at least one having two or more carbon-to-carbon double bonds the radical having only two carbon-to-carbon double bonds conjugated
- C08F236/10—Copolymers of compounds having one or more unsaturated aliphatic radicals, at least one having two or more carbon-to-carbon double bonds the radical having only two carbon-to-carbon double bonds conjugated with vinyl-aromatic monomers
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- B—PERFORMING OPERATIONS; TRANSPORTING
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- C08F297/00—Macromolecular compounds obtained by successively polymerising different monomer systems using a catalyst of the ionic or coordination type without deactivating the intermediate polymer
- C08F297/02—Macromolecular compounds obtained by successively polymerising different monomer systems using a catalyst of the ionic or coordination type without deactivating the intermediate polymer using a catalyst of the anionic type
- C08F297/04—Macromolecular compounds obtained by successively polymerising different monomer systems using a catalyst of the ionic or coordination type without deactivating the intermediate polymer using a catalyst of the anionic type polymerising vinyl aromatic monomers and conjugated dienes
- C08F297/044—Macromolecular compounds obtained by successively polymerising different monomer systems using a catalyst of the ionic or coordination type without deactivating the intermediate polymer using a catalyst of the anionic type polymerising vinyl aromatic monomers and conjugated dienes using a coupling agent
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- C08F8/00—Chemical modification by after-treatment
- C08F8/30—Introducing nitrogen atoms or nitrogen-containing groups
- C08F8/32—Introducing nitrogen atoms or nitrogen-containing groups by reaction with amines
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- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F8/00—Chemical modification by after-treatment
- C08F8/42—Introducing metal atoms or metal-containing groups
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- C08L15/00—Compositions of rubber derivatives
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- C08L9/06—Copolymers with styrene
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- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/80—Technologies aiming to reduce greenhouse gasses emissions common to all road transportation technologies
- Y02T10/86—Optimisation of rolling resistance, e.g. weight reduction
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Abstract
The present invention relates to a branched conjugated diene polymer, a method for producing the same, a method for producing a rubber composition, and a method for producing a tire, and provides a method for producing a branched conjugated diene polymer excellent in fuel consumption, abrasion resistance, wet skid resistance, and breaking strength. A process for producing a branched conjugated diene polymer, comprising the steps of: a polymerization step of polymerizing a conjugated diene compound or copolymerizing a conjugated diene compound with an aromatic vinyl compound using an alkali metal compound or an alkaline earth metal compound as a polymerization initiator, thereby obtaining a conjugated diene polymer having an active terminal; and a branching step of reacting a styrene derivative as a branching agent with the active end of the conjugated diene polymer to introduce a branched structure.
Description
Technical Field
The present invention relates to a branched conjugated diene polymer, a method for producing the same, a method for producing a rubber composition, and a method for producing a tire.
Background
Conventionally, there has been an increasing demand for fuel consumption reduction in automobiles from the viewpoint of environmental load. In particular, for an automobile tire, improvement in fuel economy is demanded for materials used for a tread portion that directly contacts the ground.
In recent years, development of a material having a small rolling resistance, that is, a low hysteresis loss has been demanded.
Meanwhile, since the tire tends to be lightweight, it is necessary to reduce the thickness of the tread portion of the tire, and at the same time, a material having high abrasion resistance is demanded for the tread portion of the tire.
On the other hand, materials used for the tread portion of a tire are required to have excellent wet skid resistance and practically sufficient failure characteristics from the viewpoint of safety.
As a material that meets such various requirements, there is mentioned a rubber material containing a rubbery polymer and a reinforcing filler such as carbon black or silica.
When a rubber material containing silicon oxide is used, the balance between low hysteresis loss (an index of low fuel consumption) and wet skid resistance can be improved. In addition, by introducing a functional group having affinity or reactivity with silica into the molecular terminal portion of the rubbery polymer having high mobility, dispersibility of silica in the rubber material can be improved, and further, mobility of the molecular terminal portion of the rubbery polymer can be reduced by binding with silica particles, so that hysteresis loss can be reduced.
On the other hand, as a method for improving the abrasion resistance, a method of increasing the molecular weight of the rubbery polymer is mentioned. However, when the molecular weight is increased, the processability of the rubber-like polymer when kneaded with the reinforcing filler tends to be deteriorated.
In view of this, attempts have been made to introduce a branched structure into a rubbery polymer in order to increase the molecular weight without impairing the processability.
For example, a resin composition comprising a modified conjugated diene polymer (obtained by reacting an amino group-containing alkoxysilane with the active end of the conjugated diene polymer) and a silica has been proposed.
Further, a modified conjugated diene polymer having a branched structure (obtained by coupling a polyfunctional silane compound with a polymer active end) introduced therein has been proposed (for example, see patent documents 1 and 2).
Prior art literature
Patent literature
Patent document 1: international publication No. 2007/114203 pamphlet
Patent document 2: international publication 2016/133154 pamphlet
Disclosure of Invention
Problems to be solved by the invention
However, in the method of introducing a branched structure into a conjugated diene polymer such as by coupling a reactive end of the polymer with a polyfunctional silane compound, the degree of branching of the modified conjugated diene polymer obtained by this method depends largely on the number of groups capable of reacting with the reactive end of the polymer of the polyfunctional silane compound, and does not become equal to or larger than the reactive groups. The following problems exist from the point of view of the synthetic possibilities: the number of reactive groups that can be imparted to 1 polyfunctional silane is limited, and thus the branching degree of the resulting modified conjugated diene polymer is also limited.
Accordingly, an object of the present invention is to provide a method for producing a branched conjugated diene polymer, which can produce a conjugated diene polymer having a high degree of branching and can adjust the length of a main chain and a side chain, and which has a high degree of freedom in polymer design, by introducing a branching point into the main chain, as compared with the case of introducing a branched structure into a conjugated diene polymer using only a modifier or a coupling agent; this provides a process for producing a branched conjugated diene polymer excellent in fuel consumption, abrasion resistance, wet skid resistance and breaking strength.
Means for solving the problems
The present inventors have made intensive studies to solve the problems of the prior art and as a result, have found a method for producing a branched conjugated diene polymer capable of introducing a branching point into the main chain by reacting a specific styrene derivative as a branching agent with a conjugated diene polymer having an active end, thereby completing the present invention.
Namely, the present invention is as follows.
[1]
A process for producing a branched conjugated diene polymer, comprising the steps of:
a polymerization step of polymerizing a conjugated diene compound or copolymerizing a conjugated diene compound with an aromatic vinyl compound using an alkali metal compound or an alkaline earth metal compound as a polymerization initiator, thereby obtaining a conjugated diene polymer having an active terminal; and
And a branching step of reacting a styrene derivative as a branching agent with the active end of the conjugated diene polymer to introduce a branched structure.
[2]
The method for producing a branched conjugated diene polymer according to [1] above, wherein the method further comprises a step of adding a conjugated diene compound and/or an aromatic vinyl compound to the reaction system during and/or after the branching step.
[3]
The method for producing a branched conjugated diene polymer according to [1] or [2], which further comprises a reaction step of reacting a coupling agent or a polymerization terminator with the active end of the conjugated diene polymer obtained in the branching step.
[4]
The method for producing a branched conjugated diene polymer according to [3], wherein the coupling agent has a nitrogen atom-containing group.
[5]
The method for producing a branched conjugated diene polymer according to [3], wherein the polymerization terminator has a nitrogen atom-containing group.
[6]
The method for producing a branched conjugated diene polymer according to [3] or [5], wherein the polymerization terminator is an alkoxide compound having a nitrogen atom-containing group.
[7]
The method for producing a branched conjugated diene polymer according to [4] above, wherein the coupling agent is represented by the following formula (a).
[ chemical 1]
(in the formula (a), R 1 ~R 4 Each independently represents an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, R 5 ~R 6 Each independently represents an alkylene group having 1 to 20 carbon atoms.
m and n are integers of 1 to 3, wherein in formula (a), a plurality of R 1 ~R 6 The m, n may be the same or different.
In the formula (a), X is represented by any one of the following general formulae (b) to (e). )
[ chemical 2]
(in the formula (b), R 7 The hydrocarbon group having 1 to 20 carbon atoms may have a partially branched structure or a cyclic structure. R is R 8 Represents a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and the hydrocarbon group may have a partially branched structure or a cyclic structure. )
[ chemical 3]
(A)(c) Wherein R is 9 Represents a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and the hydrocarbon group may have a partially branched structure or a cyclic structure. )
[ chemical 4]
(in the formula (d), R 10 Represents a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and the hydrocarbon group may have a partially branched structure or a cyclic structure. )
[ chemical 5]
(in the formula (e), R is 11 ~R 14 Each independently represents an alkylene group having 1 to 20 carbon atoms. R is R 15 ~R 18 Each independently represents an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and l and o each independently represent an integer of 1 to 3, R in the case where plural numbers are present 15 ~R 18 Each independent. )
[8]
The method for producing a branched conjugated diene polymer according to any one of the above [1] to [7], wherein the styrene derivative is a compound represented by the following formula (1) and/or the following formula (2).
[ chemical 6]
[ chemical 7]
(in the formulas (1) and (2), R 1 Represents a group selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 20 carbon atoms and an alkyl group having 6 to 2 carbon atoms0 may have a branched structure in a part thereof.
X 1 、X 2 、X 3 Is a single bond or contains an organic group selected from any one of the group consisting of carbon, hydrogen, nitrogen, sulfur and oxygen.
Y 1 、Y 2 、Y 3 Represents any one selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, and a halogen atom. Y is Y 1 、Y 2 、Y 3 Each of which may be the same or different. )
[9]
As described above [8 ]]The process for producing a branched conjugated diene polymer according to the above formula (1), wherein R 1 Is a hydrogen atom, Y 1 Is any one selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, and a halogen atom.
[10]
As described above [8 ]]The process for producing a branched conjugated diene polymer according to the above formula (2), wherein Y 2 Is any one selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, and a halogen atom.
[11]
As described above [8 ]]The process for producing a branched conjugated diene polymer according to the above formula (1), wherein R 1 Is a hydrogen atom, Y 1 Is an alkoxy group having 1 to 20 carbon atoms or a halogen atom.
[12]
As described above [8 ]]The process for producing a branched conjugated diene polymer according to the above formula (2), wherein Y 2 Is an alkoxy group having 1 to 20 carbon atoms or a halogen atom, Y 3 Is an alkoxy group having 1 to 20 carbon atoms or a halogen atom.
[13]
As described above [8 ]]The process for producing a branched conjugated diene polymer according to the above formula (1), wherein R 1 Is a hydrogen atom, Y 1 An alkoxy group having 1 to 20 carbon atoms.
[14]
As described above [8 ]]The process for producing a branched conjugated diene polymer according to the above formula (1), wherein R 1 Is a hydrogen atom, X 1 Is a single bond, Y 1 An alkoxy group having 1 to 20 carbon atoms.
[15]
As described above [8 ]]The process for producing a branched conjugated diene polymer according to the above formula (2), wherein X 2 Is a single bond, Y 2 Is an alkoxy group having 1 to 20 carbon atoms or a halogen atom, X 3 Is a single bond, Y 3 Is an alkoxy group having 1 to 20 carbon atoms or a halogen atom.
[16]
A branched conjugated diene polymer is a reaction product of a conjugated diene polymer having an active end with a branched structure and a compound represented by the following formula (a).
[ chemical 8]
(in the formula (a), R 1 ~R 4 Each independently represents an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, R 5 ~R 6 Each independently represents an alkylene group having 1 to 20 carbon atoms.
m and n are integers of 1 to 3, wherein in formula (a), a plurality of R 1 ~R 6 The m, n may be the same or different.
In the formula (a), X is represented by any one of the following general formulae (b) to (e). )
[ chemical 9]
(in the formula (b), R 7 The hydrocarbon group having 1 to 20 carbon atoms may have a partially branched structure or a cyclic structure. R is R 8 Represents a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, in the case of a hydrocarbon groupMay have a partially branched structure and a cyclic structure. )
[ chemical 10]
(in the formula (c), R 9 Represents a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and the hydrocarbon group may have a partially branched structure or a cyclic structure. )
[ chemical 11]
(in the formula (d), R 10 Represents a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and the hydrocarbon group may have a partially branched structure or a cyclic structure. )
[ chemical 12]
(in the formula (e), R is 11 ~R 14 Each independently represents an alkylene group having 1 to 20 carbon atoms. R is R 15 ~R 18 Each independently represents an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and l and o each independently represent an integer of 1 to 3, R in the case where plural numbers are present 15 ~R 18 Each independent. )
[17]
As described above [16]]The branched conjugated diene polymer of (a), wherein OR of the compound represented by the formula (a) 1 and/OR OR 3 Has a branched structure.
[18]
A rubber composition comprising:
a rubber component comprising 10 mass% or more of the branched conjugated diene polymer described in the above [16] or [17 ]; and
the filler is 5.0 to 150 parts by mass based on 100 parts by mass of the rubber component.
[19]
A method for producing a rubber composition, comprising the steps of:
a step of obtaining a branched conjugated diene polymer by the production method described in any one of [1] to [15 ];
a step of obtaining a rubber component containing 10 mass% or more of the branched conjugated diene polymer; and
a step of obtaining a rubber composition containing 5.0 parts by mass to 150 parts by mass of a filler per 100 parts by mass of the rubber component.
[20]
A method for manufacturing a tire, comprising the steps of:
a step of obtaining a rubber composition by the method for producing a rubber composition described in the above [19 ]; and
and a step of molding the rubber composition to obtain a tire.
ADVANTAGEOUS EFFECTS OF INVENTION
According to the present invention, it is possible to provide a method for producing a branched conjugated diene polymer, which can produce a branched conjugated diene polymer having a high degree of branching and can adjust the length of the main chain and the side chain, and which has a high degree of freedom in polymer design, by introducing branching points into the main chain, as compared with the case where only a modifier or a coupling agent is used; this provides a process for producing a branched conjugated diene polymer excellent in fuel consumption, abrasion resistance, wet skid resistance and breaking strength.
Detailed Description
Hereinafter, a specific embodiment of the present invention (hereinafter referred to as "the present embodiment") will be described in detail.
The present embodiment described below is an example for explaining the present invention, and the present invention is not limited to the following embodiment. The present invention can be implemented by appropriately modifying the scope of the gist thereof.
[ method for producing branched conjugated diene Polymer ]
The method for producing a branched conjugated diene polymer according to the present embodiment comprises the following steps:
a polymerization step of polymerizing a conjugated diene compound or copolymerizing a conjugated diene compound with an aromatic vinyl compound using an alkali metal compound or an alkaline earth metal compound as a polymerization initiator, thereby obtaining a conjugated diene polymer having an active terminal; and
And a branching step of reacting a styrene derivative as a branching agent with the active end of the conjugated diene polymer to introduce a branched structure.
The conjugated diene polymer constituting the branched conjugated diene polymer may be any of a homopolymer of a single conjugated diene compound, a copolymer which is a polymer of a different kind of conjugated diene compound, and a copolymer of a conjugated diene compound and an aromatic vinyl compound.
According to the method for producing a branched conjugated diene polymer of the present embodiment, by introducing a branching point into the main chain, a conjugated diene polymer having a high degree of branching can be produced, and the length of the main chain and the side chain can be adjusted, as compared with the case where a branched structure is introduced into a conjugated diene polymer using only a coupling agent.
(polymerization step)
In the polymerization step in the method for producing a branched conjugated diene polymer according to the present embodiment, a conjugated diene compound is polymerized or a conjugated diene compound is copolymerized with an aromatic vinyl compound using an alkali metal compound or an alkaline earth metal compound as a polymerization initiator, thereby obtaining a conjugated diene polymer having an active terminal.
In the polymerization step, the polymerization is preferably carried out by a growth reaction by living anionic polymerization, whereby a conjugated diene polymer having a living terminal can be obtained.
< polymerization initiator >
As the polymerization initiator, an alkali metal compound or an alkaline earth metal compound is used.
The polymerization initiator is preferably an organolithium compound, more preferably an organolithium compound.
Examples of the organolithium compound include, but are not limited to, organolithium compounds such as low molecular weight compounds and organolithium compounds such as solubilized oligomers.
In addition, as for the organic mono-lithium compound, for example, any one of a compound having carbon-lithium bond, a compound having nitrogen-lithium bond, and a compound having tin-lithium bond can be used in terms of the bonding form of the organic group and the lithium.
The amount of the polymerization initiator to be used is preferably determined according to the molecular weight of the target conjugated diene-based polymer.
The amount of the monomer such as the conjugated diene compound relative to the amount of the polymerization initiator is related to the degree of polymerization of the target conjugated diene polymer. I.e. have a tendency to be related to the number average molecular weight and/or the weight average molecular weight.
Therefore, the amount of the polymerization initiator may be adjusted in a direction to decrease the molecular weight of the conjugated diene polymer, and the amount of the polymerization initiator may be adjusted in a direction to increase the molecular weight.
Among the organomonolithium compounds, an alkyllithium compound having a substituted amino group or a dialkyllithium amide is preferable in that the organomonolithium compound can be used as one method for introducing a nitrogen atom into a conjugated diene polymer.
In this case, a conjugated diene polymer having a nitrogen atom forming an amino group at the polymerization initiation end can be obtained.
The substituted amino group is an amino group having a structure which does not have active hydrogen or which protects active hydrogen.
Examples of the alkyllithium compound having an amino group having no active hydrogen include, but are not limited to, 3-dimethylaminopropyl lithium, 3-diethylaminopropyl lithium, 4- (methylpropylamino) butyl lithium, and 4-hexamethyleneiminobutyl lithium.
Examples of the alkyllithium compound having an amino group having a structure protecting active hydrogen include, but are not limited to, 3-bistrimethylsilylaminopropyllithium and 4-trimethylsilylmethylaminobutyllithium.
Examples of the lithium dialkylamide include, but are not limited to, lithium dimethylamide, lithium diethylamide, lithium dipropylamide, lithium dibutylamide, lithium di-n-hexylamide, lithium diheptylamide, lithium diisopropylamide, lithium dioctylamide, lithium di-2-ethylhexyl amide, lithium didecylamide, lithium ethylpropylamide, lithium ethylbutylamine, lithium ethylbenzylamide, lithium methylphenylamide, lithium hexamethyleneimide, lithium pyrrolidinyl, lithium piperidinyl, lithium heptamethyleneimide, lithium morpholinyl, 1-lithium azacyclooctane, 6-lithium-1, 3-trimethyl-6-azabicyclo [3.2.1] octane, and 1-lithium-1, 2,3, 6-tetrahydropyridine.
These organomonolithium compounds having a substituted amino group may be used in the form of organomonolithium compounds of oligomers which are soluble in n-hexane or cyclohexane by reacting them with a polymerizable monomer such as 1, 3-butadiene, isoprene, styrene, or the like in a small amount.
The organolithium compound is preferably an alkyllithium compound in view of ease of industrial availability and ease of polymerization control. In this case, a conjugated diene polymer having an alkyl group at the polymerization initiation end can be obtained.
Examples of the alkyl lithium compound include, but are not limited to, n-butyllithium, sec-butyllithium, tert-butyllithium, n-hexyllithium, benzyllithium, phenyllithium, and stilbenelithium.
As the alkyl lithium compound, n-butyllithium and sec-butyllithium are preferable from the viewpoints of easiness of industrial availability and easiness of polymerization control.
These organolithium compounds may be used alone in an amount of 1 or 2 or more. In addition, other organometallic compounds may be used in combination.
Examples of the other organometallic compound include an alkaline earth metal compound, other alkali metal compound, and other organometallic compound.
Examples of the alkaline earth metal compound include, but are not limited to, for example, an organomagnesium compound, an organocalcium compound, and an organostrontium compound. In addition, alkoxide, sulfonate, carbonate, and amide compounds of alkaline earth metals can be mentioned.
Examples of the organomagnesium compound include dibutylmagnesium and ethylbutylmagnesium.
Examples of the other organometallic compound include an organoaluminum compound.
In the polymerization step, examples of the polymerization reaction form include, but are not limited to, batch-type (also referred to as "batch-type") and continuous-type polymerization reaction forms.
In the continuous type, 1 or 2 or more reactors may be used. For example, a tank type or tube type reactor with a stirrer is used as the continuous reactor. In the continuous type, it is preferable to continuously charge the monomer, the inert solvent, and the polymerization initiator into a reactor in which a polymer solution containing the polymer is obtained, and continuously discharge the polymer solution.
For example, a batch reactor is used, which is a tank reactor with a stirrer. In the batch type, it is preferable to charge the monomer, the inert solvent and the polymerization initiator, continuously or intermittently add the monomer as needed during the polymerization, obtain a polymer solution containing the polymer in the reactor, and discharge the polymer solution after the polymerization is terminated.
In the method for producing a branched conjugated diene polymer according to the present embodiment, in order to obtain a conjugated diene polymer having an active end in a high proportion by the polymerization step, a continuous type is preferable in which the polymer can be continuously discharged and supplied to a subsequent reaction in a short period of time. In the continuous type, the number of reactors is not particularly limited, and 1 or 2 or more reactors may be used. The reactor is preferably a tank type or a tube type reactor with a stirrer, in which the monomer and the polymerization initiator are sufficiently contacted in a solution. The number of reactors may be appropriately selected, but is preferably 1 from the viewpoint of saving the space of the production facility, and is preferably 2 or more from the viewpoint of improving productivity. When 2 or more reactors are used, a branching agent described later is more preferably added after the 2 nd reactor.
The polymerization step of the conjugated diene polymer is preferably performed in an inert solvent.
Examples of the inert solvent include hydrocarbon solvents such as saturated hydrocarbons and aromatic hydrocarbons. Examples of the hydrocarbon solvent include, but are not limited to, aliphatic hydrocarbons such as butane, pentane, hexane, and heptane; alicyclic hydrocarbons such as cyclopentane, cyclohexane, methylcyclopentane, methylcyclohexane, and the like; aromatic hydrocarbons such as benzene, toluene and xylene, and hydrocarbons composed of a mixture of these.
Before the polymerization reaction, the allenes and acetylenes as impurities are treated with an organometallic compound, whereby a conjugated diene polymer having a high concentration of active terminals tends to be obtained, and a modified conjugated diene polymer having a high modification ratio tends to be obtained, which is preferable.
In the polymerization step, a polar compound may be added. Thereby, the aromatic vinyl compound and the conjugated diene compound can be randomly copolymerized. The polar compound tends to be used as a vinylating agent for controlling the microstructure of the conjugated diene portion. In addition, the polymer tends to exhibit an effect in promoting a polymerization reaction or the like.
Examples of the polar compound include, but are not limited to, ethers such as tetrahydrofuran, diethyl ether, dioxane, ethylene glycol dimethyl ether, ethylene glycol dibutyl ether, diethylene glycol dimethyl ether, diethylene glycol dibutyl ether, dimethoxybenzene, and 2, 2-bis (2-tetrahydrofuranyl) propane; tertiary amine compounds such as tetramethyl ethylenediamine, dipiperidylethane, trimethylamine, triethylamine, pyridine, quinuclidine, and the like; alkali metal alkoxide compounds such as potassium tert-butoxide, sodium amyl alcohol, etc.; phosphine compounds such as triphenylphosphine.
These polar compounds may be used alone or in combination of 1 or more than 2.
The amount of the polar compound to be used is not particularly limited, and may be selected according to the purpose, and is preferably 0.01 mol to 100 mol based on 1 mol of the polymerization initiator.
Such a polar compound (vinylating agent) can be used appropriately as a regulator of the microstructure of the conjugated diene portion of the conjugated diene polymer according to the desired amount of vinyl bonding.
Most polar compounds also have an effective randomizing effect in the copolymerization of a conjugated diene compound and an aromatic vinyl compound, and tend to be used as a distribution regulator for the aromatic vinyl compound and as a regulator for the styrene block amount.
As a method for randomizing the conjugated diene compound and the aromatic vinyl compound, for example, a method in which a copolymerization reaction is initiated by using the entire amount of styrene and a part of 1, 3-butadiene and the remaining 1, 3-butadiene is intermittently added during the copolymerization reaction as described in JP-A-59-140211 is available.
The polymerization temperature in the polymerization step is preferably a temperature at which living anionic polymerization is performed, and more preferably 0 ℃ to 120 ℃ in terms of productivity.
When the polymerization temperature is in such a range, the reaction amount of the branching agent and the coupling agent with respect to the active end after termination of the polymerization tends to be sufficiently ensured. The polymerization temperature is more preferably 50℃to 100 ℃.
(branching step)
In the method for producing a branched conjugated diene polymer according to the present embodiment, a branching step of reacting a styrene derivative as a branching agent with the active end of the conjugated diene polymer obtained in the above-described polymerization step is performed.
The branched structure is formed in the polymer by allowing the branching agent to maintain polymerization activity to polymerize with the monomer and react with the functional groups of the branching agent with the active ends of the other polymer chains. The branched conjugated diene polymer having a branched structure may be further formed into a branched structure by further polymerizing and reacting the monomer with a branching agent, or may be formed into a modified conjugated diene polymer by reacting with a modifying agent having a functional group, or may be further elongated by a coupling reaction. Thus, the target branched conjugated diene polymer is obtained by using, as the branching agent, a styrene derivative in which the polymerization reaction is continued as an aromatic vinyl compound and the functional group reacts with the active end of the polymer.
< branching agent >
In the styrene derivative used as a branching agent in the branching step, it is necessary to have a skeleton in which only 1 active end remains in the branched portion after the branching reaction as a main skeleton in terms of the polymerization continuation and gelation prevention, and it is necessary that the styrene derivative portion formed after the branching reaction has sufficient reactivity with other polymerization active ends.
More specifically, the styrene derivative is preferably a compound having a vinyl group on a benzene ring and a functional group quantitatively reacting with a polymerization active end of living anion polymerization. The functional group of the styrene derivative reacts with the polymerization active terminal one by one, the functional group is detached to form a single bond, and the vinyl group reacts with other monomers in the reactor to form a branched structure in the polymer. The functional group other than vinyl group of the styrene derivative is a group which is released by nucleophilic substitution reaction with the polymerization active end of living anion polymerization, and examples thereof include an alkoxy group, a halogen group, an ester group, a formyl group, a ketone group, an amide group, an acid chloride group, an acid anhydride group, and an epoxy group.
By having such a structure, while the styrene derivative maintains polymerization activity as styrene, the styrene derivative is introduced into the main chain, and the other monomer is further polymerized with the activity-maintaining terminal, thereby further elongating the polymer chain. In addition, the branched structure can be obtained by reacting the active end of the other polymer chain with the functional group of the introduced styrene derivative to form a bond. By repeating this reaction, the branches of the polymer chain increase, the polymer structure becomes more complex, and the molecular weight further increases.
From the viewpoints of the persistence of polymerization and the controllability of the polymer structure, it is also necessary that the functional group which is detached after the reaction of the styrene derivative moiety with the active end of other polymer chains has little inhibitory effect on polymerization. The term "less inhibition of polymerization" as used herein means that the chain transfer reaction, which is a side reaction of anionic polymerization, is less likely to be deactivated during polymerization, or the activity is less likely to be lowered due to an increase in the degree of association of the polymer.
The functional group of the styrene derivative needs to be a functional group that does not excessively increase the polymerization activity, and further needs to be a functional group that does not deactivate the polymerization activity. In the case of polymerizing a polymer by living anionic polymerization, as a functional group which does not deactivate the active end, it is important that the hard base has no hydrogen atom and is defined by the Pearson-based HASB principle, and more specifically, an alkoxy group and a halogen group are exemplified. Among these, the structure of the styrene derivative used as a branching agent in the production method of the present embodiment may be selected from the viewpoints of reactivity with the active end and that the functional group to be detached does not inhibit polymerization.
More specifically, from the viewpoint of inhibiting chain transfer reaction, inhibiting deactivation of the active end, and preventing gelation, it is preferable to use a branching agent represented by the following formula (1) having a styrene skeleton as the main skeleton or by the formula (2) having a diphenylethylene skeleton as the main skeleton.
[ chemical 13]
[ chemical 14]
(in the formulas (1) and (2), R 1 Represents any one selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, and an aryl group having 6 to 20 carbon atoms, and may have a branched structure in a part thereof.
X 1 、X 2 、X 3 Is a single bond or contains any one selected from the group consisting of carbon, hydrogen, nitrogen, sulfur and oxygenA machine group.
Y 1 、Y 2 、Y 3 Represents any one selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, and a halogen atom. Y is Y 1 、Y 2 、Y 3 Each of which may be the same or different. )
Regarding the styrene derivative as the branching agent used in the branching step, R is preferable in the above formula (1) from the viewpoint of increasing the branching degree of the polymerization 1 Is a hydrogen atom, Y 1 Is any one selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, and a halogen atom.
In the present embodiment, regarding the styrene derivative as the branching agent used in the branching step, Y is preferable in the above formula (2) from the viewpoint of improving the branching degree 2 Is any one selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, and a halogen atom.
In the present embodiment, regarding the styrene derivative as the branching agent used in the branching step, R is more preferable in the above formula (1) from the viewpoints of the persistence of polymerization and the improvement of branching degree 1 Is a hydrogen atom, Y 1 Is an alkoxy group having 1 to 20 carbon atoms or a halogen atom.
In the present embodiment, regarding the styrene derivative as the branching agent used in the branching step, Y is more preferable in the above formula (2) from the viewpoints of the persistence of polymerization and the improvement of branching degree 2 Is an alkoxy group or a halogen atom, Y 3 Is an alkoxy group having 1 to 20 carbon atoms or a halogen atom.
In the present embodiment, regarding the styrene derivative as the branching agent used in the branching step, R is more preferable in the above formula (1) from the viewpoints of the persistence of polymerization, the improvement of branching degree, and the improvement of modification rate 1 Is a hydrogen atom, Y 1 An alkoxy group having 1 to 20 carbon atoms.
In the present embodiment, the branching agent used in the branching step is styrene-derivedThe polymer is more preferably R in the above formula (1) from the viewpoints of the persistence of polymerization, the improvement of branching degree and the further improvement of modification rate 1 Is a hydrogen atom, X 1 Is a single bond, Y 1 An alkoxy group having 1 to 20 carbon atoms.
In the present embodiment, regarding the styrene derivative as the branching agent used in the branching step, X is more preferable in the above formula (2) from the viewpoints of the persistence of polymerization, the improvement of branching degree, and further improvement of the modification ratio 2 Is a single bond, Y 2 Is an alkoxy group having 1 to 20 carbon atoms or a halogen atom, X 3 Is a single bond, Y 3 Is an alkoxy group having 1 to 20 carbon atoms or a halogen atom.
Examples of the branching agent represented by the above formula (1) include, but are not limited to, trimethoxy (4-vinylphenyl) silane, triethoxy (4-vinylphenyl) silane, tripropoxy (4-vinylphenyl) silane, tributoxy (4-vinylphenyl) silane, triisopropoxy (4-vinylphenyl) silane, trimethoxy (3-vinylphenyl) silane, triethoxy (3-vinylphenyl) silane, tripropoxy (3-vinylphenyl) silane, tributoxy (3-vinylphenyl) silane, triisopropoxy (3-vinylphenyl) silane, trimethoxy (2-vinylphenyl) silane, triethoxy (2-vinylphenyl) silane, tripropoxy (2-vinylphenyl) silane, triisopropoxy (2-vinylphenyl) silane, dimethoxymethyl (4-vinylphenyl) silane, diethoxymethyl (4-vinylphenyl) silane, dipropoxymethyl (4-vinylphenyl) silane, di-butoxymethyl (4-vinylphenyl) silane, di-methoxypropyl (4-vinylphenyl) silane, di-methoxypropyl (3-vinylphenyl) silane, di-vinylphenyl) silane, and the like, diethoxymethyl (3-vinylphenyl) silane, dipropoxymethyl (3-vinylphenyl) silane, dibutoxymethyl (3-vinylphenyl) silane, diisopropyloxymethyl (3-vinylphenyl) silane, dimethoxymethyl (2-vinylphenyl) silane, diethoxymethyl (2-vinylphenyl) silane, dipropoxymethyl (2-vinylphenyl) silane, dibutoxymethyl (2-vinylphenyl) silane, diisopropyloxymethyl (2-vinylphenyl) silane, dimethylmethoxy (4-vinylphenyl) silane, dimethylethoxy (4-vinylphenyl) silane, dimethylpropoxy (4-vinylphenyl) silane, dimethylbutoxy (4-vinylphenyl) silane, dimethylisopropoxy (4-vinylphenyl) silane, dimethylmethoxy (3-vinylphenyl) silane, dimethylethoxy (3-vinylphenyl) silane, dimethylpropoxy (3-vinylphenyl) silane, dimethylisopropoxy (3-vinylphenyl) silane, dimethylmethoxy (2-vinylphenyl) silane, dimethylethoxy (2-vinylphenyl) silane, dimethylpropoxy (2-ethenylphenyl) silane, dimethylbutoxy (2-ethenylphenyl) silane, dimethylisopropoxy (2-ethenylphenyl) silane, trimethoxy (4-isopropenylphenyl) silane, triethoxy (4-isopropenylphenyl) silane, tripropoxy (4-isopropenylphenyl) silane, triisopropoxy (4-isopropenylphenyl) silane, trimethoxy (3-isopropenylphenyl) silane, triethoxy (3-isopropenylphenyl) silane, tripropoxy (3-isopropenylphenyl) silane, tributoxy (3-isopropenylphenyl) silane, triisopropoxy (3-isopropenylphenyl) silane, trimethoxy (2-isopropenylphenyl) silane, triethoxy (2-isopropenylphenyl) silane, triisopropoxy (2-isopropenylphenyl) silane, dimethoxymethyl (4-isopropenyl) silane, diisopropenylphenyl (4-diisopropenylphenyl) silane, diisopropenyl4-diisopropenylsilane, diisopropoxymethyl (4-isopropenylphenyl) silane, dimethoxymethyl (3-isopropenylphenyl) silane, diethoxymethyl (3-isopropenylphenyl) silane, dipropoxymethyl (3-isopropenylphenyl) silane, diisopropoxymethyl (3-isopropenylphenyl) silane, dimethoxymethyl (2-isopropenylphenyl) silane, diethoxymethyl (2-isopropenylphenyl) silane, dipropoxymethyl (2-isopropenylphenyl) silane, dibutoxymethyl (2-isopropenylphenyl) silane, diisopropoxymethyl (2-isopropenylphenyl) silane, dimethylmethoxy (4-isopropenylphenyl) silane, dimethylethoxy (4-isopropenylphenyl) silane, dimethylpropoxy (4-isopropenylphenyl) silane, dimethylbutoxy (4-isopropenylphenyl) silane, dimethylisopropoxy (4-isopropenyl) silane, dimethylmethoxy (3-isopropenyl) silane, dimethylethoxy (3-isopropenyl) silane, diisopropenyl3-isopropenyl) silane, dimethyl isopropoxy (3-isopropenylphenyl) silane, dimethyl methoxy (2-isopropenylphenyl) silane, dimethyl ethoxy (2-isopropenylphenyl) silane, dimethyl propoxy (2-isopropenylphenyl) silane, dimethyl butoxy (2-isopropenylphenyl) silane, dimethyl isopropoxy (2-isopropenylphenyl) silane, trichloro (4-vinylphenyl) silane, trichloro (3-vinylphenyl) silane, trichloro (2-vinylphenyl) silane, tribromo (4-vinylphenyl) silane, tribromo (3-vinylphenyl) silane, tribromo (2-vinylphenyl) silane, dichloromethyl (4-vinylphenyl) silane, dichloromethyl (3-vinylphenyl) silane, dichloromethyl (2-vinylphenyl) silane, dibromomethyl (2-vinylphenyl) silane, dimethylchloro (4-vinylphenyl) silane, dimethylchloro (3-vinylphenyl) silane, dibromomethyl (2-vinylphenyl) silane, dibromo (3-vinylphenyl) silane, dibromomethyl (2-vinylphenyl) silane), dimethyl bromo (2-vinylphenyl) silane, trimethoxy (4-vinylbenzyl) silane, triethoxy (4-vinylbenzyl) silane, tripropoxy (4-vinylbenzyl) silane.
Among these, trimethoxy (4-vinylphenyl) silane, triethoxy (4-vinylphenyl) silane, tripropoxy (4-vinylphenyl) silane, triisopropoxy (4-vinylphenyl) silane, trimethoxy (3-vinylphenyl) silane, triethoxy (3-vinylphenyl) silane, tripropoxy (3-vinylphenyl) silane, tributoxy (3-vinylphenyl) silane, triisopropoxy (3-vinylphenyl) silane, trichloro (4-vinylphenyl) silane, more preferably trimethoxy (4-vinylphenyl) silane, triethoxy (4-vinylphenyl) silane, tripropoxy (4-vinylphenyl) silane, triisopropoxy (4-vinylphenyl) silane, trimethoxy (4-vinylbenzyl) silane, triethoxy (4-vinylbenzyl) silane, still more preferably trimethoxy (4-vinylphenyl) silane, triethoxy (4-vinylphenyl) silane.
As the branching agent represented by the above formula (2), examples thereof include, but are not limited to, 1-bis (4-trimethoxysilylphenyl) ethylene, 1-bis (4-triethoxysilylphenyl) ethylene, 1-bis (4-tripropoxysilylphenyl) ethylene, 1-bis (4-tripentyloxysilylphenyl) ethylene 1, 1-bis (4-triisopropoxysilylphenyl) ethylene, 1-bis (3-trimethoxysilylphenyl) ethylene, 1-bis (3-triethoxysilylphenyl) ethylene, 1-bis (3-tripropoxysilylphenyl) ethylene 1, 1-bis (4-triisopropoxysilylphenyl) ethylene, 1-bis (3-trimethoxysilylphenyl) ethylene 1, 1-bis (3-triethoxysilylphenyl) ethylene, 1-bis (3-tripropoxysilylphenyl) ethylene, 1, 1-bis (4- (dipropylmethoxysilyl) phenyl) ethylene, 1-bis (4- (dimethylethoxysilyl) phenyl) ethylene, 1-bis (4- (diethylethoxysilyl) phenyl) ethylene, 1-bis (4- (dipropylethoxysilyl) phenyl) ethylene 1, 1-bis (4-trimethoxysilylbenzyl) ethylene, 1-bis (4-triethoxysilylbenzyl) ethylene, 1-bis (4-tripropoxysilylbenzyl) ethylene, 1-bis (4-tripentyloxysilylbenzyl) ethylene.
Among these, 1-bis (4-trimethoxysilylphenyl) ethylene, 1-bis (4-triethoxysilylphenyl) ethylene, 1-bis (4-tripropoxysilylphenyl) ethylene, 1-bis (4-tripentyloxysilylphenyl) ethylene, 1-bis (4-triisopropoxysilylphenyl) ethylene, and more preferably 1, 1-bis (4-trimethoxysilylphenyl) ethylene are preferred.
By using the branching agent represented by the above formulas (1) and (2), the number of branches is increased, and the effect of improving abrasion resistance and processability is obtained.
The timing of adding the branching agent is not particularly limited and may be selected according to the purpose, and from the viewpoint of increasing the absolute molecular weight of the branched conjugated diene polymer and increasing the coupling ratio, the raw material conversion after adding the polymerization initiator is preferably 20% or more, more preferably 40% or more, still more preferably 50% or more, still more preferably 65% or more, still more preferably 75% or more.
The monomer as a desired raw material may be further added at the time of the branching step and/or after the branching step, and the polymerization step may be continued after the branching step, or the above description may be repeated.
The term "after the branching step" is defined as after the addition of the branching agent.
The monomer to be added is not particularly limited, but is preferably a conjugated diene compound and/or an aromatic vinyl compound, and in particular, in the case of adding a monomer in the branching step, it is preferably 5% or more, more preferably 15% or more, still more preferably 20% or more, still more preferably 25% or more of the total amount of conjugated diene monomers (for example, the total amount of butadiene) used in the polymerization step, from the viewpoint of improving the modification rate by reducing the steric hindrance at the branching point of the conjugated diene polymer. In this case, it is particularly preferable to add the monomer at 5% or more of the total amount of the conjugated diene monomer (for example, the total amount of butadiene) used in the polymerization step in the branching step by using the continuous polymerization process, from the viewpoint of improving the modification ratio.
The length of the main chain and the side chain can be adjusted by the timing of adding the branching agent and the amount of the added monomer, so that the degree of freedom in designing the polymer is high.
The branched conjugated diene polymer obtained in the branching step in the method for producing a branched conjugated diene polymer according to the present embodiment preferably has a branched structure of 3 to 24 branches, more preferably 4 to 20 branches, and still more preferably 5 to 18 branches.
The polymer having 24 or less branches tends to be easily reacted with a modifier having a functional group to produce a modified conjugated diene polymer, and the polymer chain tends to be further elongated by a coupling reaction, and the polymer obtained having 3 or more branches tends to be excellent in processability and abrasion resistance.
The amount of the branching agent to be added is not particularly limited, and may be selected in accordance with the purpose, and from the viewpoints of increasing the end-termination reaction rate, increasing the coupling rate, and increasing the polymerization durability after branching of the conjugated diene polymer, the molar ratio of the branching agent to the amount of the living polymerization initiator is preferably one half or more, more preferably one third or more and fifty-half or more, still more preferably one fourth or more and thirty-half or more, still more preferably one sixth or less and twenty-fifth or more, and still more preferably one eighth or more.
Further, as described above, the monomer may be further added at the time of the branching step and/or after the branching step, and the polymerization step may be continued after the branching, or the branching agent may be further added after the addition of the monomer, and the addition of the monomer may be repeated.
By adding the monomer, the effect of improving the polymerization persistence and the coupling ratio and the modification ratio can be obtained by reducing the steric hindrance around the branching point. Thus, the molecular weight of the polymer can be increased and a branched structure can be formed at a desired position.
The additional monomer may be an aromatic vinyl compound such as styrene, a conjugated diene compound such as butadiene, or a mixture of these, and may be the same as or different from the type and the ratio of the monomer to be initially polymerized, and the conjugated diene compound is preferable in view of the durability of the polymerization. From the viewpoint of improving the heat resistance of the polymer, it is preferable to add an aromatic vinyl compound.
The Mooney viscosity of the branched conjugated diene polymer obtained in the branching step in the production method of the present embodiment is preferably 10 to 150, more preferably 15 to 140, still more preferably 20 to 130, as measured at 110 ℃. More preferably 30 to 100.
When the mooney viscosity is in the above range, the branched conjugated diene polymer obtained by the production method of the present embodiment tends to be excellent in processability and abrasion resistance.
The weight average molecular weight of the branched conjugated diene polymer obtained by the branching step in the production method of the present embodiment is preferably 10000 to 1500000, more preferably 100000 to 1000000, still more preferably 200000 to 900000.
When the weight average molecular weight is within the above range, the branched conjugated diene polymer obtained by the production method of the present embodiment tends to be excellent in processability, abrasion resistance and a balance of their properties.
In order to achieve a weight average molecular weight in the range of 100000 to 1000000, the amount of the branching agent to be added is controlled to be one third or more and one fifth or more in terms of a molar ratio relative to the polymerization initiator, whereby it is necessary to prevent the polymerization initiator from being completely consumed before the coupling step while forming a branch, and to have the number of functional groups of the coupling agent be 2 or more. In order to achieve a weight average molecular weight in the range of 200000 to 900000, it is necessary to control the amount of the branching agent to be added in the range of one third or more and one fiftieth or more in terms of a molar ratio relative to the polymerization initiator, and to control the number of functional groups of the coupling agent to be 3 or more.
In the case of producing a modified branched conjugated diene polymer, in order to achieve a weight average molecular weight in the range of 100000 to 1000000, it is necessary to control the amount of the branching agent to be added in the range of one third or less and one fiftieth or more in terms of a molar ratio relative to the polymerization initiator, to prevent the polymerization initiator from being completely consumed before the coupling step while forming a branch, and to make the number of functional groups of the coupling agent 2 or more; in order to achieve a weight average molecular weight in the range of 200000 to 900000, it is necessary to control the amount of the branching agent to be added in the range of one third or more and one fiftieth or more in terms of a molar ratio relative to the polymerization initiator, and to control the number of functional groups of the coupling agent to be 3 or more.
The branched conjugated diene polymer obtained by the production method of the present embodiment may be a polymer of a conjugated diene monomer and a branching agent, or may be a copolymer of a conjugated diene monomer, a branching agent, and monomers other than these.
For example, when the conjugated diene monomer is butadiene or isoprene and is polymerized with a branching agent containing an aromatic vinyl moiety, a polymer having a structure in which a polymer chain is so-called polybutadiene or polyisoprene and a branched moiety contains an aromatic vinyl group is formed. By having such a structure, the linearity of each 1 chain of the polymer chain and the crosslinking density after vulcanization can be improved, thereby exerting an effect of improving the abrasion resistance of the polymer. Therefore, the rubber composition is suitable for applications such as tires, resin-modified products, automobile interior/exterior products, vibration-proof rubbers, and footwear.
When the conjugated diene polymer is used for a tread of a tire, a copolymer of a conjugated diene monomer, an aromatic vinyl monomer, and a branching agent is preferable, and the amount of conjugated diene bonded in the copolymer for use is preferably 40 mass% or more and 100 mass% or less, more preferably 55 mass% or more and 80 mass% or less.
The amount of the bonded aromatic vinyl group in the branched conjugated diene polymer obtained by the production method of the present embodiment is not particularly limited, but is preferably 0% by mass or more and 60% by mass or less, more preferably 20% by mass or more and 45% by mass or less.
When the amount of the conjugated diene and the amount of the aromatic vinyl are in the above ranges, the balance between low hysteresis loss and wet skid resistance after the production of a vulcanized product tends to be more excellent in abrasion resistance and failure characteristics.
The amount of the conjugated diene can be determined by measuring the amount of the aromatic vinyl group by ultraviolet absorption of the phenyl group. Specifically, the measurement can be performed by the method described in examples described below.
In the branched conjugated diene polymer obtained by the production method of the present embodiment, the amount of vinyl groups bonded to the conjugated diene bonding units is not particularly limited, but is preferably 10 to 75 mol%, more preferably 20 to 65 mol%.
When the vinyl bond content is within the above range, the balance between low hysteresis loss and wet skid resistance after the production of a sulfide, abrasion resistance, and breaking strength tend to be more excellent.
Here, when the branched conjugated diene polymer is a copolymer of butadiene and styrene, the vinyl bond amount (1, 2-bond amount) in the butadiene-bonded unit can be determined by the Hampton method (r.r. Hampton, analytical Chemistry,21,923 (1949)). Specifically, the measurement can be performed by the method described in examples described below.
The microstructure of the branched conjugated diene polymer tends to be such that a sulfide having a low hysteresis loss and a further excellent balance between wet skid resistance can be obtained when the amount of each bond in the branched conjugated diene polymer obtained by the production method of the present embodiment is in the above-described numerical range and the glass transition temperature of the branched conjugated diene polymer is in the range of-80 ℃ to-15 ℃.
Regarding the glass transition temperature, the temperature was raised in a predetermined temperature range in accordance with ISO 22768:2006, and a DSC curve was recorded at the same time, and the peak top (inflection point) of the DSC differential curve was regarded as the glass transition temperature.
When the branched conjugated diene polymer obtained by the production method of the present embodiment is a conjugated diene-aromatic vinyl copolymer, it is preferable that the branched conjugated diene polymer has a small or no number of blocks in which 30 or more aromatic vinyl units are linked. More specifically, in the case where the branched conjugated diene polymer obtained by the production method of the present embodiment is a butadiene-styrene copolymer, in a known method in which the polymer is decomposed by the method of Kolthoff (method described in i.m. Kolthoff, et al, j.polym.sci.1,429 (1946)) and the amount of polystyrene insoluble in methanol is analyzed, the block in which 30 or more aromatic vinyl units are linked is preferably 5.0 mass% or less, more preferably 3.0 mass% or less, relative to the total amount of the branched conjugated diene polymer.
When the branched conjugated diene polymer obtained by the production method of the present embodiment is a conjugated diene-aromatic vinyl copolymer, it is preferable that the aromatic vinyl unit is present in a large proportion alone, from the viewpoint of improving fuel economy.
Specifically, in the case where the branched conjugated diene Polymer obtained by the production method of the present embodiment is a butadiene-styrene copolymer, the branched conjugated diene Polymer is decomposed by an ozonolysis method known as a method of field et al (Polymer, 22,1721 (1981)), and the styrene linkage distribution is analyzed by GPC, at this time, the amount of separated styrene is preferably 40 mass% or more and the linked styrene structure having 8 or more styrene chains is 5.0 mass% or less with respect to the total amount of bound styrene.
In this case, the hysteresis loss of the vulcanized rubber obtained tends to be particularly low, and the excellent performance tends to be exhibited.
(reaction step)
In the method for producing a branched conjugated diene polymer according to the present embodiment, it is preferable to perform a step of coupling the active end of the conjugated diene polymer obtained in the polymerization step or the branching step with a coupling agent (for example, a reactive compound having 3 or more functions), or a step of reacting the active end of the conjugated diene polymer with a polymerization terminator (for example, a reactive compound having 2 or less functions).
The step of reacting the coupling agent (coupling step) or the step of reacting the polymerization terminator (polymerization termination step) is hereinafter collectively referred to as a reaction step.
In the reaction step, one end of the active end of the conjugated diene polymer is reacted with a coupling agent or a polymerization terminator.
< coupling procedure >
In the method for producing a conjugated diene polymer according to the present embodiment, it is preferable that the method includes a coupling step of coupling the conjugated diene polymer obtained through the polymerization and branching step with a coupling agent. The molecular chain can be effectively extended by the coupling step, and a branched chain can be introduced into the polymer by using a coupling agent having 3 or more functions. The function of forming the branched chain is communicated with the step of using the branching agent, but it is preferable to use a coupling step to form the branched chain while introducing a desired element such as nitrogen, sulfur, or silicon, using a known coupling agent.
As the coupling step, for example, a coupling step using a reactive compound having 3 or more functions for the active end of the conjugated diene polymer or a coupling step using a coupling agent having a group containing a nitrogen atom (hereinafter, may be collectively referred to as "coupling agent"), and more preferably a coupling step using a coupling agent represented by the following formula (a) is preferable.
In the coupling step, for example, a reactive compound having 3 or more functions, a coupling agent having a group containing a nitrogen atom, or a coupling agent represented by the following formula (a) may be used at one end of the active end of the conjugated diene polymer to perform a coupling reaction, thereby obtaining a branched conjugated diene polymer.
[ reactive Compound having 3 Functions or more ]
In the method for producing a branched conjugated diene polymer according to the present embodiment, the reactive compound having 3 or more functions used in the coupling step is preferably a reactive compound having 3 or more functions having a silicon atom.
Examples of the reactive compound having 3 or more functions including a silicon atom include, but are not limited to, halosilane compounds, epoxysilane compounds, vinylsilane compounds, alkoxysilane compounds, and the like.
Examples of the halosilane compound which is a coupling agent include, but are not limited to, methyltrichlorosilane, tetrachlorosilane, tris (trimethylsiloxy) chlorosilane, tris (dimethylamino) chlorosilane, hexachlorodisilane, bis (trichlorosilyl) methane, 1, 2-bis (trichlorosilyl) ethane, 1, 2-bis (methyldichlorosilyl) ethane, 1, 4-bis (trichlorosilyl) butane, and 1, 4-bis (methyldichlorosilyl) butane.
Examples of the epoxysilane compound which is a coupling agent include, but are not limited to, 3-epoxypropoxypropyl trimethoxysilane, 3-epoxypropoxypropyl triethoxysilane, 3-epoxypropoxypropyl methyldiethoxysilane, and epoxy-modified silicone.
Examples of alkoxysilane compounds which are coupling agents include, but are not limited to, tetramethoxysilane, tetraethoxysilane, triphenoxymethylsilane, 1, 2-bis (triethoxysilyl) ethane, methoxy-substituted polyorganosiloxanes, and the like.
[ coupling agent having a group containing a nitrogen atom ]
Examples of the coupling agent having a group containing a nitrogen atom include, but are not limited to, isocyanate compounds, isothiocyanate compounds, isocyanuric acid derivatives, carbonyl compounds having a group containing a nitrogen atom, vinyl compounds having a group containing a nitrogen atom, epoxy compounds having a group containing a nitrogen atom, alkoxysilane compounds having a group containing a nitrogen atom, and protected amine compounds having a group containing a nitrogen atom and capable of forming primary or secondary amines.
Among the coupling agents having a group containing a nitrogen atom, the functional group containing a nitrogen atom may preferably be a functional group derived from an amine compound having no active hydrogen, and examples of the amine compound include a tertiary amine compound and a protected amine compound in which the active hydrogen is substituted with a protecting group. Examples of the other compounds capable of forming a functional group containing a nitrogen atom include an imine compound represented by the general formula-n=c, and an alkoxysilane compound bonded to the above group containing a nitrogen atom.
Examples of the isocyanate compound which is a coupling agent having a nitrogen atom-containing group include, but are not limited to, 2, 4-benzylidene diisocyanate, 2, 6-benzylidene diisocyanate, diphenylmethane diisocyanate, polymeric diphenylmethane diisocyanate (C-MDI), phenyl isocyanate, isophorone diisocyanate, hexamethylene diisocyanate, butyl isocyanate, 1,3, 5-benzene triisocyanate, and the like.
Examples of the isocyanuric acid derivative which is a coupling agent having a nitrogen atom-containing group include, but are not limited to, 1,3, 5-tris (3-trimethoxysilylpropyl) isocyanurate, 1,3, 5-tris (3-triethoxysilylpropyl) isocyanurate, 1,3, 5-tris (oxiran-2-yl) -1,3, 5-triazine-2, 4, 6-trione, 1,3, 5-tris (isocyanatomethyl) -1,3, 5-triazine-2, 4, 6-trione, 1,3, 5-trivinyl-1, 3, 5-triazine-2, 4, 6-trione, and the like.
Examples of the carbonyl compound which is a coupling agent having a nitrogen atom-containing group include, but are not limited to, 1, 3-dimethyl-2-imidazolidinone, 1-methyl-3-ethyl-2-imidazolidinone, 1-methyl-3- (2-methoxyethyl) -2-imidazolidinone, N-methyl-2-pyrrolidone, N-methyl-2-piperidone, N-methyl-2-quinolone, 4 '-bis (diethylamino) benzophenone, 4' -bis (dimethylamino) benzophenone, methyl-2-pyridylketone, methyl-4-pyridylketone, propyl-2-pyridylketone, di-4-pyridylketone, 2-benzoylpyridine, N, N, N ', N' -tetramethylurea, N-dimethyl-N ', N' -diphenylurea, N-diethylcarbamic acid methyl group, N-diethylacetamide, N, N-dimethyl-N ', N' -dimethylaminoacetamide, N-dimethylpyridine carboxamide, N-dimethylisonicotinamide, and the like.
Examples of the vinyl compound which is a coupling agent having a nitrogen atom-containing group include, but are not limited to, N-dimethylacrylamide, N-dimethylmethacrylamide, N-methylmaleimide, N-methylphthalimide, N, N-bistrimethylsilylacrylamide, morpholinoacrylamide, 3- (2-dimethylaminoethyl) styrene, (dimethylamino) dimethyl-4-vinylphenylsilane, 4 '-vinylidene bis (N, N-dimethylaniline), 4' -vinylidene bis (N, N-diethylaniline), 1-bis (4-morpholinophenyl) ethylene, 1-phenyl-1- (4-N, N-dimethylaminophenyl) ethylene, and the like.
Examples of the epoxy compound which is a coupling agent having a nitrogen atom-containing group include, but are not limited to, an epoxy group-containing hydrocarbon compound bonded to an amino group, and an epoxy group-containing hydrocarbon compound bonded to an ether group.
Examples of such an epoxy compound include, but are not limited to, an epoxy compound represented by the general formula (i).
[ 15]
In the above formula (i), R is a hydrocarbon group having a valence of 2 or more, or an organic group having at least one polar group selected from the group consisting of a polar group having oxygen such as an ether, an epoxy, and a ketone, a polar group having sulfur such as a thioether, and a thioketone, a polar group having nitrogen such as a tertiary amino group, and an imino group.
The hydrocarbon group having a valence of 2 or more may be a saturated or unsaturated hydrocarbon group which may be linear, branched or cyclic, and includes an alkylene group, an alkenylene group, a phenylene group and the like. Preferably a hydrocarbon group having 1 to 20 carbon atoms. Examples thereof include methylene, ethylene, butylene, cyclohexylene, 1, 3-bis (methylene) -cyclohexane, 1, 3-bis (ethylene) -cyclohexane, o-phenylene, m-phenylene, p-phenylene, m-xylylene, p-xylylene, and bis (phenylene) -methane.
In the above formula (i), R 1 、R 4 Is a hydrocarbon group of 1 to 10 carbon atoms, R 1 、R 4 May be the same or different from each other.
In the above formula (i), R 2 、R 5 Is hydrogen or C1-10 alkyl, R 2 、R 5 May be the same or different from each other.
In the above formula (i), R 3 Is a hydrocarbon group having 1 to 10 carbon atoms, or a structure represented by the following formula (ii).
R 1 、R 2 、R 3 Can be a ring structure formed by combining with each other.
In addition, R 3 In the case of the hydrocarbon group, the hydrocarbon group may have a cyclic structure in which R is bonded to each other. In the case of the above cyclic structure, R is bonded to 3 The N and R may be in the form of direct bonding.
In the above formula (i), n is an integer of 1 or more, and m is an integer of 0 or 1 or more.
[ 16]
In the above formula (ii), R 1 、R 2 R is the same as the R of the formula (i) 1 、R 2 Similarly defined, R 1 、R 2 May be the same or different from each other.
The epoxy compound which is a coupling agent having a nitrogen atom-containing group is preferably a hydrocarbon group having an epoxy group, more preferably a hydrocarbon group having a glycidyl group.
The epoxy group-containing hydrocarbon group bonded to the amino group or the ether group is not particularly limited, and examples thereof include a glycidylamino group, a diglycidyl amino group, and a glycidyloxy group. Further preferred molecular structures are epoxy group-containing compounds each having a glycidylamino group or a diglycidyl amino group, and examples thereof include compounds represented by the following general formula (iii).
[ chemical 17]
In the above formula (iii), R is defined as R in the above formula (i), R 6 Is a hydrocarbon group having 1 to 10 carbon atoms or a structure represented by the following formula (iv).
R 6 In the case of hydrocarbon groups, R may be bonded to each other to form a cyclic structure, in which case R is bonded to 6 The combined N and R may be directForm of binding.
In the formula (iii), n is an integer of 1 or more, and m is 0 or an integer of 1 or more.
[ chemical 18]
The epoxy compound which is a coupling agent having a nitrogen atom-containing group is particularly preferably a compound having 1 or more diglycidyl amino groups and 1 or more glycidoxy groups in the molecule.
Examples of the epoxy compound used as the coupling agent having a nitrogen atom-containing group include, but are not limited to, N, N-diglycidyl-4-glycidoxyphenylamine, 1-N, N-diglycidyl aminomethyl-4-glycidoxypyclohexane, 4- (4-glycidoxyphenyl) - (N, N-diglycidyl) aniline, 4- (4-glycidoxyphenoxy) - (N, N-diglycidyl) aniline, 4- (4-glycidoxybenzyl) - (N, N-diglycidyl) aniline, 4- (N, N '-diglycidyl-2-piperazinyl) -glycidoxyphenylamine, 1, 3-bis (N, N-diglycidyl aminomethyl) cyclohexane, N, N, N', N '-tetraglycidyl m-xylylenediamine, 4-methylene-bis (N, N-diglycidyl aniline), 1, 4-bis (N, N-diglycidyl amino) cyclohexane, N, N, N', N '-tetraglycidyl, 4' -bis (4-diglycidyl) aniline, 4-bis (4-glycidyl-2-glycidyl-p-phenylenediamine, N, N-diglycidyl-2-glycidyl-phenylenediamine, 4-bis (4-diglycidyl-amino) aniline, 4-bis (4-diglycidyl-2-glycidyl-methyl) aniline N, N-diglycidyl aniline, 4' -diglycidyl dibenzylmethylamine, N-diglycidyl aniline, N-diglycidyl o-toluidine, N-diglycidyl aminomethylcyclohexane, and the like. Particularly preferred compounds among these are N, N-diglycidyl-4-glycidoxy aniline and 1, 3-bis (N, N-diglycidyl aminomethyl) cyclohexane.
Examples of the alkoxysilane compound which is a coupling agent having a nitrogen atom-containing group include, but are not limited to, 3-dimethylaminopropyl trimethoxysilane, 3-dimethylaminopropyl methyldimethoxysilane, 3-diethylaminopropyl triethoxysilane, 3-morpholinopropyltrimethoxysilane, 3-piperidyl propyltriethoxysilane, 3-hexamethyleneiminopropyl methyldiethoxysilane, 3- (4-methyl-1-piperazinyl) propyltriethoxysilane, 1- [3- (triethoxysilyl) -propyl ] -3-methylhexahydropyrimidine, 3- (4-trimethylsilyl-1-piperazinyl) propyltriethoxysilane, 3- (3-triethylsilyl-1-imidazolidinyl) propylmethyldiethoxysilane, 3- (3-trimethylsilyl-1-hexahydropyrimidinyl) propyltrimethoxysilane, 3-dimethylamino-2- (dimethylaminomethyl) propyltrimethoxysilane, bis (3-dimethoxymethylsilylpropyl) -N-methylamino, bis (3-trimethoxysilylpropyl) -N-methylamino, bis (3-triethoxysilyl) -trimethylamine, N-trimethoxysilylamino (trimethoxysilylamino) N, N, N-trimethoxysilylamino-N, N, N' -trimethoxysilylamino-N. N' -tetrakis (3-trimethoxysilylpropyl) ethylenediamine, 3-isocyanatopropyl trimethoxysilane, 3-cyanopropyl trimethoxysilane, 2-dimethoxy-1- (3-trimethoxysilylpropyl) -1-aza-2-silacyclopentane, 2-diethoxy-1- (3-triethoxysilylpropyl) -1-aza-2-silacyclopentane, 2-dimethoxy-1- (4-trimethoxysilylbutyl) -1-aza-2-silacyclohexane 2, 2-dimethoxy-1- (3-dimethoxymethylsilylpropyl) -1-aza-2-silacyclopentane, 2-dimethoxy-1-phenyl-1-aza-2-silacyclopentane, 2-diethoxy-1-butyl-1-aza-2-silacyclopentane, 2-dimethoxy-1-methyl-1-aza-2-silacyclopentane, 2-dimethoxy-8- (4-methylpiperazino) methyl-1, 6-dioxa-2-silacyclooctane, 2-dimethoxy-8- (N), n-diethylamino) methyl-1, 6-dioxa-2-silacyclooctane, and the like.
Examples of the protected amine compound which is a coupling agent having a nitrogen atom-containing group and which can form a primary amine or a secondary amine include, but are not limited to, 4' -vinylidene bis [ N, N-bis (trimethylsilyl) aniline ], 4' -vinylidene bis [ N, N-bis (triethylsilyl) aniline ], 4' -vinylidene bis [ N, N-bis (t-butyldimethylsilyl) aniline ], 4' -vinylidenebis [ N-methyl-N- (trimethylsilyl) aniline ], 4' -vinylidenebis [ N-ethyl-N- (trimethylsilyl) aniline ], 4' -vinylidenebis [ N-methyl-N- (triethylsilyl) aniline ]: 4,4' -vinylidenebis [ N-ethyl-N- (triethylsilyl) aniline ], 4' -vinylidenebis [ N-methyl-N- (tert-butyldimethylsilyl) aniline ], 4' -vinylidenebis [ N-ethyl-N- (tert-butyldimethylsilyl) aniline ], 1- [4-N, N-bis (trimethylsilyl) aminophenyl ] -1- [ 4-N-methyl-N- (trimethylsilyl) aminophenyl ] ethylene, 1- [4-N, n-bis (trimethylsilyl) aminophenyl ] -1- [4-N, N-dimethylaminophenyl ] ethylene, and the like.
Examples of the protected amine compound which is a coupling agent having a nitrogen atom-containing group and can form a primary amine or a secondary amine include, but are not limited to, N-bis (trimethylsilyl) aminopropyl trimethoxysilane, N-bis (trimethylsilyl) aminopropyl methyldimethoxysilane, N-bis (trimethylsilyl) aminopropyl triethoxysilane, N-bis (trimethylsilyl) aminopropyl methyldiethoxysilane, N-bis (trimethylsilyl) aminoethyltrimethoxysilane, N, N-bis (trimethylsilyl) aminoethylmethyldiethoxysilane, N-bis (triethylsilyl) aminopropylmethyldiethoxysilane, 3- (4-trimethylsilyl-1-piperazinyl) propyltriethoxysilane, 3- (3-triethylsilyl-1-imidazolidinyl) propylmethyldiethoxysilane, 3- (3-trimethylsilyl-1-hexahydropyrimidinyl) propyltrimethoxysilane, 2-dimethoxy-1- (3-trimethoxysilylpropyl) -1-aza-2-silacyclopentane, 2-diethoxy-1- (3-triethoxysilylpropyl) -1-aza-2-silacyclopentane, 2, 2-dimethoxy-1- (4-trimethoxysilylbutyl) -1-aza-2-silacyclopentane, 2-dimethoxy-1- (3-dimethoxymethylsilylpropyl) -1-aza-2-silacyclopentane, 2-dimethoxy-1-phenyl-1-aza-2-silacyclopentane, 2-diethoxy-1-butyl-1-aza-2-silacyclopentane, 2-dimethoxy-1-methyl-1-aza-2-silacyclopentane, N- (1, 3-dimethylbutyl) -3- (triethoxysilyl) -1-propanamine, N- (1-methylethylene) -3- (triethoxysilyl) -1-propanamine, N-ethylene-3- (triethoxysilyl) -1-propanamine, N- (1-methylpropylene) -3- (triethoxysilyl) -1-propanamine, N- (4-N, N-dimethylaminobenzylidene) -3- (triethoxysilyl) -1-propanamine and the like, N- (1-methylpropylene) -1- (triethoxysilyl) -1-propanamine can be exemplified by N- (3-ethoxysilyl) -1-propanamine, N- (1, 3-dimethylbutylidene) -3- (triethoxysilyl) -1-propylamine, 3- (benzylamino) propyltrimethoxysilane, 3- (benzylamino) propyltriethoxysilane, 3- (benzylamino) propyltripropylsilane, and the like.
Examples of the alkoxysilane compound which is a coupling agent having a nitrogen atom-containing group include, but are not limited to, tris (3-trimethoxysilylpropyl) amine, tris (3-triethoxysilylpropyl) amine, tris (3-tripropoxysilylpropyl) amine, bis (3-trimethoxysilylpropyl) - [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] amine, tetrakis (3-trimethoxysilylpropyl) -1, 3-propanediamine, tris (3-trimethoxysilylpropyl) - [3- (1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl ] -1, 3-propanediamine, tris (3-trimethoxysilylpropyl) - [3- (1-methoxy-2-methyl-1-sila-2-azacyclopentane) propyl ] -1, 3-propanediamine, bis (3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl ] - [3- (1-methoxy-2-sila-2-azacyclopentane) propyl ] -1, 3-trimethoxysilylpropyl-1-aza-silapentane, tetrakis (3-trimethoxysilylpropyl) -1, 3-bis-aminomethylcyclohexane, tris (3-trimethoxysilylpropyl) - [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] -1, 3-bis-aminomethylcyclohexane, tetrakis (3-trimethoxysilylpropyl) -1, 6-hexamethylenediamine, penta (3-trimethoxysilylpropyl) -diethylenetriamine, tris (3-trimethoxysilylpropyl) -methyl-1, 3-propanediamine, tetrakis [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] silane, bis (3-trimethoxysilylpropyl) -bis [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] silane, tris [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] - (3-trimethoxysilylpropyl) silane, tris [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] - [3- (2-trimethoxysilylpropyl) propyl ] silane, tris [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] silane, 3-tris [2- (2, 2-dimethoxy-1-aza-2-silacyclopentane) ethoxy ] silyl-1-trimethoxysilylpropane, 1- [3- (1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl ] -3,4, 5-tris (3-trimethoxysilylpropyl) -cyclohexane, 1- [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] -3,4, 5-tris (3-trimethoxysilylpropyl) -cyclohexane, 3,4, 5-tris (3-trimethoxysilylpropyl) -cyclohexyl- [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] ether, (3-trimethoxysilylpropyl) phosphate, bis (3-trimethoxysilylpropyl) - [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] phosphate, bis [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] - (3-trimethoxysilylpropyl) phosphate and tris [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] phosphate.
[ coupling agent represented by formula (a) ]
In the method for producing a branched conjugated diene polymer according to the present embodiment, it is preferable to carry out a reaction step of reacting the compound [ a ] represented by the following formula (a) with the active end of the conjugated diene polymer having a branched structure introduced therein obtained through the above polymerization step and branching step.
The compound [ A ] is a compound having 2 or more in total alkoxysilyl groups containing nitrogen atoms, and the structure represented by X in the formula (a) is the structures represented by the formulae (b) to (e).
By performing the reaction step using the coupling agent represented by the formula (a), a branched conjugated diene polymer having a large number of branches in the polymer chain and modified with a group that interacts with silica can be obtained.
[ chemical 19]
In the formula (a), R 1 ~R 4 Each independently represents an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, R 5 ~R 6 Each independently represents an alkylene group having 1 to 20 carbon atoms.
m and n are integers of 1 to 3, wherein in formula (a), a plurality of R 1 ~R 6 The m, n may be the same or different.
In the formula (a), X is represented by any one of the following general formulae (b) to (e).
[ chemical 20]
In the formula (b), R 7 The hydrocarbon group having 1 to 20 carbon atoms may have a partially branched structure or a cyclic structure. R is R 8 Represents a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and the hydrocarbon group may have a partially branched structure or a cyclic structure.
[ chemical 21]
In the formula (c), R 9 Represents a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and the hydrocarbon group may have a partially branched structure or a cyclic structure.
[ chemical 22]
In the formula (d), R 10 Represents a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and the hydrocarbon group may have a partially branched structure or a cyclic structure.
[ chemical 23]
In the formula (e), R 11 ~R 14 Each independently represents an alkylene group having 1 to 20 carbon atoms.
R 15 ~R 18 Each independently represents an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and l and o each independently represent an integer of 1 to 3, R in the case where plural numbers are present 15 ~R 18 Each independent.
The compound [ A ] used in the modification step, that is, the reaction step may be, for example, but not limited to, compounds represented by the following formulae (A-1) to (A-16).
The compound [ A ] may be used alone or in combination of 1 or more than 2.
< Compound [ A ] used in the modification step: formulae (A-1) to (A-16)
[ chemical 24]
[ chemical 25]
[ chemical 26]
In the above formulas (A-1) to (A-16), et is ethyl, and Me is methyl.
The reaction between the conjugated diene polymer having an active end obtained in the branching step and the compound [ A ] represented by the above formula (a) may be carried out, for example, as a solution reaction.
The proportion of the compound [ A ] used (in the case of using 2 or more kinds, the total amount thereof) is preferably 0.01 mol or more, more preferably 0.05 mol or more, based on 1 mol of the metal atom involved in the polymerization, which is included in the polymerization initiator, in terms of sufficiently performing the coupling reaction. In addition, the upper limit value is preferably less than 2.0 moles, more preferably less than 1.5 moles, relative to 1 mole of the metal atom involved in polymerization, which is possessed by the polymerization initiator, in order to avoid excessive addition.
The temperature of the coupling reaction using the compound [ A ] represented by the above formula (a) is usually the same as that of the polymerization reaction, and is preferably-20℃to 150℃and more preferably 0℃to 120 ℃. If the reaction temperature is low, the viscosity of the polymer after the coupling reaction tends to increase, and if the reaction temperature is high, the polymerization active end is easily deactivated. The reaction time is preferably 1 minute to 5 hours, more preferably 2 minutes to 1 hour.
When the conjugated diene polymer having an active end obtained in the branching step is reacted with the compound [ A ] represented by the formula (a), other modifier or coupling agent may be used together with the compound [ A ].
The other modifier or coupling agent is not particularly limited as long as it is a compound capable of reacting with the active end of the conjugated diene polymer obtained in the above-described polymerization step and branching step, and a compound known as a modifier or coupling agent for a conjugated diene polymer can be used.
When another modifier or coupling agent is used, the proportion thereof is preferably 10 mol% or less, more preferably 5 mol% or less.
< branched conjugated diene Polymer obtained by the polymerization step, branching step and reaction step >
In the method for producing a branched conjugated diene polymer according to the present embodiment, the branched conjugated diene polymer obtained through the reaction step, particularly the step of reacting with a coupling agent, preferably has a structure derived from a compound having a nitrogen atom-containing group represented by any one of the following general formulae (i) or (a) to (C).
[ chemical 27]
In the above formula (i), R is a hydrocarbon group having a valence of 2 or more, or an organic group having a valence of 2 or more, which is selected from at least one of a polar group having oxygen such as an ether, an epoxy, a ketone, a polar group having sulfur such as a thioether, a thioketone, a polar group having nitrogen such as a tertiary amino group and an imino group.
The hydrocarbon group having a valence of 2 or more may be a saturated or unsaturated hydrocarbon group which may be linear, branched or cyclic, and includes an alkylene group, an alkenylene group, a phenylene group and the like. Preferably a hydrocarbon group having 1 to 20 carbon atoms. Examples thereof include methylene, ethylene, butylene, cyclohexylene, 1, 3-bis (methylene) -cyclohexane, 1, 3-bis (ethylene) -cyclohexane, o-phenylene, m-phenylene, p-phenylene, m-xylylene, p-xylylene, and bis (phenylene) -methane.
In the above formula (i), R 1 、R 4 Is a hydrocarbon group of 1 to 10 carbon atoms, R 1 、R 4 May be the same or different from each other.
In the above formula (i), R 2 、R 5 Is hydrogen or C1-10 alkyl, R 2 、R 5 May be the same or different from each other.
In the above formula (i), R 3 Is a hydrocarbon group having 1 to 10 carbon atoms, or a structure represented by the following formula (ii).
R 1 、R 2 、R 3 Can be a ring structure formed by combining with each other.
In addition, R 3 In the case of the hydrocarbon group, the hydrocarbon group may have a cyclic structure in which R is bonded to each other. In the case of the above-mentioned cyclic structure, R is bonded to 3 The N and R may be in the form of direct bonding.
In the formula (i), n is an integer of 1 or more, and m is an integer of 0 or 1 or more.
[ chemical 28]
In the above formula (ii), R 1 、R 2 R is the same as the R of the formula (i) 1 、R 2 Similarly defined, R 1 、R 2 May be the same or different from each other.
[ chemical 29]
(in the formula (A), R 1 ~R 4 Each independently represents an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, R 5 Represents an alkylene group having 1 to 10 carbon atoms, R 6 An alkylene group having 1 to 20 carbon atoms.
m represents an integer of 1 or 2, n represents an integer of 2 or 3, and (m+n) represents an integer of 4 or more. R in the case of plural 1 ~R 4 Each independent. )
[ chemical 30]
(in the formula (B), R 1 ~R 6 Each independently represents an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, R 7 ~R 9 Each independently represents an alkylene group having 1 to 20 carbon atoms.
m, n and l each independently represent an integer of 1 to 3, and (m+n+l) represents an integer of 4 or more. R in the case of plural 1 ~R 6 Each independent. )
[ 31]
/>
(in the formula (C), R 12 ~R 14 Each independently represents a single bond or an alkylene group having 1 to 20 carbon atoms, R 15 ~R 18 And R is 20 Each independently represents an alkyl group having 1 to 20 carbon atoms, R 19 And R is 22 R is an alkylene group having 1 to 20 carbon atoms 21 An alkyl group having 1 to 20 carbon atoms or a trialkylsilyl group.
m represents an integer of 1 to 3, and p represents 1 or 2.
R in the case where there are plural ones each 12 ~R 22 M and p are each independently the same or different.
i represents an integer of 0 to 6, j represents an integer of 0 to 6, k represents an integer of 0 to 6, and (i+j+k) is an integer of 4 to 10.
A represents a hydrocarbon group having 1 to 20 carbon atoms or an organic group having at least one atom selected from the group consisting of an oxygen atom, a nitrogen atom, a silicon atom, a sulfur atom and a phosphorus atom and having no active hydrogen. )
As the coupling agent having a group containing a nitrogen atom represented by the above formula (A), examples thereof include, but are not limited to, 2-dimethoxy-1- (3-trimethoxysilylpropyl) -1-aza-2-silacyclopentane, 2-diethoxy-1- (3-triethoxysilylpropyl) -1-aza-2-silacyclopentane, 2-dimethoxy-1- (4-trimethoxysilylbutyl) -1-aza-2-silacyclohexane, 2-dimethoxy-1- (5-trimethoxysilylpentyl) -1-aza-2-silacycloheptane 2, 2-dimethoxy-1- (3-dimethoxymethylsilylpropyl) -1-aza-2-silacyclopentane, 2-diethoxy-1- (3-diethoxyethylsilylpropyl) -1-aza-2-silacyclopentane, 2-methoxy-2-methyl-1- (3-trimethoxysilylpropyl) -1-aza-2-silacyclopentane, 2-ethoxy-2-ethyl-1- (3-triethoxysilylpropyl) -1-aza-2-silacyclopentane, 2-methoxy-2-methyl-1- (3-dimethoxymethylsilylpropyl) -1-aza-2-silacyclopentane and 2-ethoxy-2-ethyl-1- (3-diethoxyethylsilylpropyl) -1-aza-2-silacyclopentane.
Among these, m is preferably 2 and n is preferably 3 from the viewpoints of reactivity and interactivity of the functional group of the coupling agent having a nitrogen atom-containing group with the inorganic filler such as silica, and processability. Specifically, 2-dimethoxy-1- (3-trimethoxysilylpropyl) -1-aza-2-silacyclopentane and 2, 2-diethoxy-1- (3-triethoxysilylpropyl) -1-aza-2-silacyclopentane are preferred.
The reaction temperature, reaction time, etc. for reacting the coupling agent having a nitrogen atom-containing group represented by the above formula (a) with the polymerization active terminal are not particularly limited, but preferably at 0 ℃ to 120 ℃ for 30 seconds or more.
The total mole number of alkoxy groups bonded to the silyl groups in the compound of the coupling agent having a nitrogen atom-containing group represented by the above formula (a) is preferably in the range of 0.6 to 3.0 times, more preferably in the range of 0.8 to 2.5 times, still more preferably in the range of 0.8 to 2.0 times, the addition mole number of the alkali metal compound and/or alkaline earth metal compound of the polymerization initiator. The amount of the polymer terminal is preferably 0.6 times or more in view of obtaining a sufficient modification ratio, molecular weight and branched structure of the obtained branched conjugated diene polymer, and the amount of the polymer terminal is preferably 3.0 times or less in view of the cost of the coupling agent.
The number of moles of the polymerization initiator is preferably 3.0 times or more, more preferably 4.0 times or more, the number of moles of the coupling agent having a nitrogen atom-containing group represented by the above formula (a).
Examples of the coupling agent having a nitrogen atom-containing group represented by the above formula (B) include, but are not limited to, tris (3-trimethoxysilylpropyl) amine, tris (3-methyldimethoxysilylpropyl) amine, tris (3-triethoxysilylpropyl) amine, tris (3-methyldiethoxysilylpropyl) amine, tris (trimethoxysilylmethyl) amine, tris (2-trimethoxysilylethyl) amine and tris (4-trimethoxysilylbutyl) amine.
Among these, from the viewpoints of reactivity and interaction of the functional group of the coupling agent with an inorganic filler such as silica, and workability, it is preferable that n, m, and l in the above formula (B) all represent 3. As a preferred specific example, tris (3-trimethoxysilylpropyl) amine and tris (3-triethoxysilylpropyl) amine are given.
The reaction temperature, reaction time, etc. for reacting the coupling agent having a nitrogen atom-containing group represented by the above formula (B) with the active end of the conjugated diene polymer obtained in the above branching step are not particularly limited, and preferably the reaction is carried out at 0 ℃ to 120 ℃ for 30 seconds or longer.
The total mole number of alkoxy groups bonded to silyl groups in the compound of the coupling agent represented by the formula (B) is preferably in the range of 0.6 to 3.0 times, more preferably in the range of 0.8 to 2.5 times, and even more preferably in the range of 0.8 to 2.0 times, the mole number of lithium constituting the polymerization initiator. The amount of the polymer is preferably 0.6 times or more in view of obtaining a sufficient modification ratio, molecular weight and branched structure in the branched conjugated diene polymer obtained by the production method of the present embodiment, and it is preferable to couple the polymer terminals to each other to obtain a branched conjugated diene polymer component for improving processability, and it is preferable to be 3.0 times or less in view of the cost of the coupling agent.
The number of moles of the polymerization initiator is preferably 4.0 times or more, more preferably 5.0 times or more, the number of moles of the coupling agent having a nitrogen atom-containing group represented by the above formula (B).
In the above formula (C), A is preferably represented by any one of the following general formulae (II) to (V).
[ chemical 32]
(in the formula (II), B 1 Represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, and a represents an integer of 1 to 10. B1 in the case where there are plural numbers is independent of each other. )
[ 33]
(in the formula (III), B 2 Represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, B 3 An alkyl group having 1 to 20 carbon atoms, and a is an integer of 1 to 10. B in the case of plural 2 And B 3 Each independent. )
[ chemical 34]
(in the formula (IV), B 4 Represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, and a represents an integer of 1 to 10. B in the case of plural 4 Each independent. )
[ 35]
/>
(in the formula (V), B 5 Represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, and a represents an integer of 1 to 10. B in the case of plural 5 Each independent. )
Examples of the coupling agent having a nitrogen atom-containing group represented by the formula (II) in the above formula (C) include, but are not limited to, tris (3-trimethoxysilylpropyl) amine, bis (3-trimethoxysilylpropyl) - [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] amine, bis [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] - (3-trimethoxysilylpropyl) amine, tris [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] amine, tris (3-ethoxysilylpropyl) amine, bis (3-triethoxysilylpropyl) - [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl ] amine, bis [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl ] amine, tris [3- (2, 2-aza-1-silacyclopentane) propyl ] amine, and tris (3-ethoxysilylpropyl) amine Tris (3-trimethoxysilylpropyl) - [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] -1, 3-propanediamine, bis (3-trimethoxysilylpropyl) -bis [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] -1, 3-propanediamine, tris [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] - (3-trimethoxysilylpropyl) -1, 3-propanediamine, tetrakis [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] -1, 3-propanediamine, tris (3-trimethoxysilylpropyl) - [3- (1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl ] -1, 3-propanediamine, bis (3-trimethoxysilylpropyl) - [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] - [3- (1-methoxy-1-aza-2-silacyclopentane) propyl ] -3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] -1, 3-trimethoxysilylpropyl-1-silacyclopentane Bis [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] - (3-trimethoxysilylpropyl) - [3- (1-methoxy-2-trimethylsilyl-1-aza-2-silacyclopentane) propyl ] -1, 3-propanediamine, tris [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] - [3- (1-methoxy-2-trimethylsilyl-1-aza-2-silacyclopentane) propyl ] -1, 3-propanediamine, tetrakis (3-triethoxysilylpropyl) -1, 3-propanediamine, tris (3-triethoxysilylpropyl) - [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl ] -1, 3-propanediamine, bis (3-triethoxysilylpropyl) -bis [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl ] -1, 3-propanediamine, tris [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl ] - (3, 3-propanediamine, tetrakis [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl ] -1, 3-propanediamine, tris (3-triethoxysilylpropyl) - [3- (1-ethoxy-2-trimethylsilyl-1-aza-2-silacyclopentane) propyl ] -1, 3-propanediamine, bis (3-triethoxysilylpropyl) - [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl ] - [3- (1-ethoxy-2-trimethylsilyl-1-sila-2-silacyclopentane) propyl ] -1, 3-propanediamine, bis [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl ] - (3-triethoxysilylpropyl) - [3- (1-ethoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl ] -1, 3-propanediamine, tris [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl ] - [3- (1-ethoxy-2-aza-2-silacyclopentane) propyl ] -1, 3-triethoxysilylpropyl ] -1, 3-trisilyl-1-aza-2-silacyclopentane), tetrakis (3-trimethoxysilylpropyl) -1, 3-bis-aminomethylcyclohexane, tris (3-trimethoxysilylpropyl) - [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] -1, 3-bis-aminomethylcyclohexane, bis (3-trimethoxysilylpropyl) -bis [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] -1, 3-bis-aminomethylcyclohexane, tris [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] - (3-trimethoxysilylpropyl) -1, 3-bis-aminomethylcyclohexane, tetrakis [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] -1, 3-propanediamine, tris (3-trimethoxysilylpropyl) - [3- (1-methoxy-2-trimethylsilyl-1-aza-2-silacyclopentane) propyl ] -1, 3-bis-aminomethylcyclohexane, bis (3-trimethoxysilylpropyl) - [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] - [3- (1-methoxy-2-trimethylsilyl-1-aza-2-silacyclopentane) propyl ] -1, 3-bisaminomethyl cyclohexane, bis [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] - (3-trimethoxysilylpropyl) - [3- (1-methoxy-2-trimethylsilyl-1-aza-2-silacyclopentane) propyl ] -1, 3-bisaminomethyl cyclohexane, tris [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] - [3- (1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl ] -1, 3-bisaminomethyl cyclohexane, tetrakis (3-triethoxysilylpropyl) -1, 3-propanediamine, tris (3-triethoxysilylpropyl) - [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl ] -1, 3-bisaminomethyl-cyclohexane, bis (3-triethoxysilylpropyl) -bis [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl ] -1, 3-bisaminomethylcyclohexane, tris [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl ] - (3-triethoxysilylpropyl) -1, 3-propanediamine, tetrakis [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl ] -1, 3-propanediamine, tris (3-triethoxysilylpropyl) - [3- (1-ethoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl ] -1, 3-bisaminomethylcyclohexane, bis (3-triethoxysilylpropyl) - [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl ] - [3- (1-ethoxy-2-trimethylsilyl-1-silacyclopentane) propyl ] -1, 3-bisaminomethylcyclohexane, bis [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl ] - (3-triethoxysilylpropyl) - [3- (1-ethoxy-2-trimethylsilyl-1-aza-2-silacyclopentane) propyl ] -1, 3-bisaminomethylcyclohexane, tris [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl ] - [3- (1-ethoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl ] -1, 3-bisaminomethylcyclohexane, tetrakis (3-trimethoxysilylpropyl) -1, 6-hexamethylenediamine, and penta (3-trimethoxysilylpropyl) -diethylenetriamine.
Examples of the coupling agent having a nitrogen atom-containing group represented by formula (III) in formula (C) include, but are not limited to, tris (3-trimethoxysilylpropyl) -methyl-1, 3-propanediamine, bis (2-trimethoxysilylpropyl) - [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] -methyl-1, 3-propanediamine, bis [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] - (3-trimethoxysilylpropyl) -methyl-1, 3-propanediamine, tris (3-triethoxysilylpropyl) -methyl-1, 3-propanediamine, bis (2-triethoxysilylpropyl) - [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl ] -methyl-1, 3-propanediamine, bis [3- (2, 2-diethoxy-1-aza-2-silacyclopentane) propyl ] - (3-triethoxysilylpropyl) -methyl-1, 3-triethoxysilylpropyl ] -methyl-1, 3 '- (N, N-1, N-diethoxypropyl) -methyl-1, N-dimethyl-1' - (1-N-1, n3-bis (3- (trimethoxysilyl) propyl) -1, 3-propanediamine) N1- (3- (bis (3- (trimethoxysilyl) propyl) amino) propyl) -N1-methyl-N3- (3- (methyl (3- (trimethoxysilyl) propyl) amino) propyl) -N3- (3- (trimethoxysilyl) propyl) -1, 3-propanediamine.
Examples of the coupling agent having a nitrogen atom-containing group represented by formula (IV) in formula (C) include, but are not limited to, tetrakis [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] silane, tris [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] - (3-trimethoxysilylpropyl) silane, tris [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] - [3- (1-methoxy-2-trimethylsilyl-1-sila-2-azacyclopentane) propyl ] silane, bis (3-trimethoxysilylpropyl) -bis [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] silane, (3-trimethoxysilyl) - [3- (1-methoxy-2-trimethylsilyl-1-aza-2-silacyclopentane) bis [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] silane, bis [3- (1-methoxy-2-trimethylsilyl-1-aza-2-azacyclopentane) -bis [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] silane, tris (3-trimethoxysilylpropyl) - [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] silane, bis (3-trimethoxysilylpropyl) - [3- (1-methoxy-2-trimethylsilyl-1-aza-2-azacyclopentane) propyl ] - [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] silane, bis [3- (1-methoxy-2-trimethylsilyl-1-aza-2-azacyclopentane) propyl ] -bis (3-trimethoxysilylpropyl) silane, and bis [3- (1-methoxy-2-methyl-1-sila-2-azacyclopentane) propyl ] silane.
Examples of the coupling agent having a nitrogen atom-containing group represented by formula (V) in the case of a in the above formula (C) include, but are not limited to, 3-tris [2- (2, 2-dimethoxy-1-aza-2-silacyclopentane) ethoxy ] silyl-1- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propane and 3-tris [2- (2, 2-dimethoxy-1-aza-2-silacyclopentane) ethoxy ] silyl-1-trimethoxysilylpropane.
In the above formula (C), A is preferably represented by formula (II) or formula (III), and k represents 0.
Such a coupling agent having a nitrogen atom-containing group tends to be easily available, and abrasion resistance and low hysteresis loss performance after the branched conjugated diene polymer obtained by the production method of the present embodiment is formed into a sulfide tend to be more excellent. Examples of such a coupling agent having a nitrogen atom-containing group include, but are not limited to, bis (3-trimethoxysilylpropyl) - [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] amine, tris (3-trimethoxysilylpropyl) amine, tris (3-triethoxysilylpropyl) amine, tris (3-trimethoxysilylpropyl) - [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] -1, 3-propanediamine, tetrakis (3-trimethoxysilylpropyl) -1, 3-diaminomethylcyclohexane, tris (3-trimethoxysilylpropyl) -methyl-1, 3-propanediamine, and bis [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl ] - (3-trimethoxysilyl) -1, 3-propanediamine.
In the above formula (C), A is more preferably represented by the formula (II) or the formula (III), k represents 0, and in the formula (II) or the formula (III), a represents an integer of 2 to 10.
This tends to be more excellent in abrasion resistance and low hysteresis loss after vulcanization.
Examples of the coupling agent having a nitrogen atom-containing group include, but are not limited to, tetrakis [3- (2, 2-dimethoxy-1-aza-2-silacyclopentane) propyl group]-1, 3-propanediamine, tetrakis (3-trimethoxysilylpropyl) -1, 3-bis-aminomethylcyclohexane and N 1 - (3- (bis (3- (trimethoxysilyl) propyl) amino) propyl) -N 1 -methyl-N 3 - (3- (methyl (3- (trimethoxysilyl) propyl) amino) propyl) -N 3 - (3- (trimethoxysilyl) propyl) -1, 3-propanediamine.
The amount of the compound represented by the formula (C) as a coupling agent having a nitrogen atom-containing group may be adjusted so that the number of moles of the conjugated diene polymer relative to the number of moles of the coupling agent reacts in a desired stoichiometric ratio, whereby a desired star-shaped highly branched structure tends to be achieved.
The number of moles of the polymerization initiator is preferably 5.0 times or more, more preferably 6.0 times or more, the number of moles of the coupling agent having a nitrogen atom-containing group represented by the above formula (C).
In this case, in the formula (C), the number of functional groups ((m-1). Times.i+p.times.j+k) of the coupling agent is preferably an integer of 5 to 10, more preferably an integer of 6 to 10.
The proportion of the polymer having a nitrogen atom-containing group in the branched conjugated diene polymer obtained by the production method of the present embodiment is expressed as a modification ratio.
The modification ratio is preferably 60% by mass or more, more preferably 65% by mass or more, further preferably 70% by mass or more, still more preferably 75% by mass or more, further preferably 80% by mass or more, and particularly preferably 82% by mass or more.
When the modification ratio is 60 mass% or more, the workability in producing a sulfide is excellent, and the abrasion resistance and low hysteresis loss performance after producing a sulfide tend to be more excellent.
< branched conjugated diene Polymer obtained by the reaction step Using the Compound represented by the formula (a) as a coupling agent >
The branched conjugated diene polymer of the present embodiment is preferably a reaction product of a conjugated diene polymer having an active end with a branched structure and a compound represented by the following formula (a).
[ 36]
In the formula (a), R 1 ~R 4 Each independently represents an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, R 5 ~R 6 Each independently represents an alkylene group having 1 to 20 carbon atoms.
m and n are integers of 1 to 3, wherein in formula (a), a plurality of R 1 ~R 6 The m, n may be the same or different.
In the formula (a), X is represented by any one of the following general formulae (b) to (e).
[ 37]
In the formula (b), R 7 The hydrocarbon group having 1 to 20 carbon atoms may have a partially branched structure or a cyclic structure. R is R 8 Represents a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and the hydrocarbon group may have a partially branched structure or a cyclic structure.
[ 38]
In the formula (c), R 9 Represents a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and the hydrocarbon group may have a partially branched structure or a cyclic structure.
[ 39]
In the formula (d), R 10 Represents a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and the hydrocarbon group may have a partially branched structure or a cyclic structure.
[ 40]
In the formula (e), R 11 ~R 14 Each independently represents an alkylene group having 1 to 20 carbon atoms.
R 15 ~R 18 Each independently represents an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and l and o each independently represent an integer of 1 to 3, R in the case where plural numbers are present 15 ~R 18 Each independent.
In the modified conjugated diene polymer of the present embodiment, it is preferable that OR of the compound represented by the formula (a) is as described above 1 And OR 3 At least one of them has a branched structure.
Among the branched conjugated diene polymers of the present embodiment, a reaction product of the conjugated diene polymer having an active end with a branched structure obtained through the branching step and the compound represented by the above formula (a) is preferable from the viewpoint of balance of fuel saving performance, processability and abrasion resistance.
The modified conjugated diene polymer having a branched structure generally has branching points derived from a coupling agent or a modifier, and as the number of branches increases, the reactivity with silica decreases when constituting a rubber composition. In addition, in the case of a polymer having a low branching degree, the viscosity of the compound tends to increase and the processability tends to be deteriorated as the content of the coupling agent and the modifier and the molecular weight increase. Thus, it is difficult to improve the balance between the fuel saving performance and the processability and wear resistance.
In contrast, in a preferred embodiment of the branched conjugated diene polymer of the present embodiment, the compound represented by the formula (a) is OR 1 And OR 3 Since the conjugated diene polymer having at least one branched structure is preferable, the number of branches and the molecular weight can be increased without impairing the reactivity of the branched conjugated diene polymer with silicon oxide by reducing the steric hindrance around the modifier.
Accordingly, OR of the compound represented by the above formula (a) 1 And OR 3 The modified conjugated diene polymer having a branched structure is preferably an asymmetric structure, that is, preferably a backbone having a main chain branched structure is formed on one side with the coupling agent as the center, and a backbone having no main chain branched is formed on the opposite side, and further preferably the branching point of the conjugated diene polymer obtained by the branching step is separated from the branching point formed by the modifying agent by a molecular chain having a molecular weight of 1 ten thousand or more.
< polymerization termination Process >
In the method for producing a branched conjugated diene polymer according to the present embodiment, a reaction step of reacting the coupling agent or the polymerization terminator with the active terminal of the conjugated diene polymer obtained through the polymerization step and the branching step may be performed.
As the polymerization termination step, for example, a polymerization termination step using a 2-functional reactive compound for the active end of the conjugated diene polymer or a polymerization termination step using a polymerization terminator having a group containing a nitrogen atom (hereinafter, may be collectively referred to as "polymerization terminator") is preferable.
In the polymerization termination step, for example, a polymerization termination reaction may be performed on the active end of the polymer obtained in the branching step using a 2-functional reactive compound or a polymerization terminator having a nitrogen atom-containing group, to obtain the target branched conjugated diene polymer.
[2 functional reactive Compounds ]
In the method for producing a branched conjugated diene polymer according to the present embodiment, the 2-functional reactive compound used in the polymerization termination step may have any structure, and is preferably a 2-functional reactive compound having a silicon atom.
[ polymerization terminator having group containing Nitrogen atom ]
In the method for producing a branched conjugated diene polymer according to the present embodiment, the polymerization terminator having a nitrogen atom-containing group used in the polymerization termination step may have any structure, and preferably has a functional group reactive with the conjugated diene polymer.
The polymerization terminator having a nitrogen atom-containing group is preferably an alkoxy compound having a nitrogen atom-containing group in terms of improving fuel economy.
Examples of the polymerization terminator having a nitrogen atom-containing group include 3- (N, N-dimethylaminopropyl) dimethoxymethylsilane, 3- (N, N-diethylaminopropyl) dimethoxymethylsilane, 3- (N, N-dipropylaminopropyl) dimethoxymethylsilane, 3- (N, N-dimethylaminopropyl) diethoxymethylsilane, 3- (N, N-diethylaminopropyl) diethoxymethylsilane, 3- (N, N-dipropylaminopropyl) diethoxymethylsilane, 3- (N, N-dimethylaminopropyl) dimethoxyethylsilane, 3- (N, N-diethylaminopropyl) dimethoxyethylsilane, 3- (N, N-dipropylaminopropyl) dimethoxyethylsilane, 3- (N, N-dimethylaminopropyl) diethoxyethylsilane, 3- (N, N-diethylaminopropyl) diethoxyethylsilane, 3- (N, N-dipropylaminopropyl) diethoxyethylsilane, and the like.
The branched conjugated diene polymer obtained by the polymerization step, branching step, and reaction step according to the method of the present embodiment has a branched structure of more preferably 6 to 36 branches, preferably 8 to 36 branches, more preferably 8 to 24 branches, 10 to 22 branches, and still more preferably 12 to 20 branches.
The total number of branching points in the branched conjugated diene polymer obtained by the production method of the present embodiment is preferably 2 or more, more preferably 3 or more, still more preferably 4 or more, and still more preferably 5 or more.
When the total number of the branched structures and the branching points is within the above range, the processability, the fuel economy and the abrasion resistance tend to be excellent.
In the case where the branched conjugated diene polymer has a branched structure of 8 to 36 branches and is a modified polymer, it is necessary to use a branching agent in a molar ratio of not less than one half of the polymerization initiator and not less than 3 functional groups of the coupling agent in order to construct a structure in which the total number of branching points is not less than 2 and not more than 15. In the case where a modified polymer is not required, the branching point is 1 or more.
In order to construct a structure in which the branched structure is from 8 branches to 36 branches and the total number of branching points is from 3 to 12, it is preferable to use a material in which the molar ratio of the branching agent is one third or more and fifty times or more of the polymerization initiator and the number of functional groups of the coupling agent is 4 or more.
In order to construct a structure in which the branched structure is from 10 branches to 24 branches and the total number of branching points is from 4 to 10, it is preferable to use a material in which the molar ratio of the branching agent is one sixth or less and twenty-fifth or more of the polymerization initiator and the number of functional groups of the coupling agent is 5 or more.
In order to construct a structure in which the branched structure is from 12 branches to 20 branches and the total number of branching points is from 5 to 9, it is preferable to use a material in which the molar ratio of the branching agent is one eighth or more and one twelfth or more of the polymerization initiator and the number of functional groups of the coupling agent is 6 or more.
(condensation reaction step)
In the method for producing a branched conjugated diene polymer according to the present embodiment, the condensation reaction step may be performed after the coupling step or before the coupling step, and the condensation reaction may be performed in the presence of a condensation accelerator.
(hydrogenation step)
In the method for producing a branched conjugated diene polymer according to the present embodiment, a hydrogenation step of hydrogenating the conjugated diene portion may be performed.
The method for hydrogenating the conjugated diene portion of the conjugated diene polymer is not particularly limited, and a known method can be used.
As a suitable hydrogenation method, there may be mentioned a method of hydrogenation by blowing gaseous hydrogen into a polymer solution in the presence of a catalyst. The catalyst is not particularly limited, and examples thereof include heterogeneous catalysts such as a catalyst in which a noble metal is supported on a porous inorganic substance; a catalyst obtained by solubilizing a salt of nickel, cobalt or the like and reacting the same with an organoaluminum or the like, a homogeneous catalyst such as a catalyst using a metallocene such as cyclopentadienyl titanium or the like. Among these, from the viewpoint of being able to select mild hydrogenation conditions, a cyclopentadienyl titanium catalyst is preferred. In addition, hydrogenation of the aromatic group can be performed by using a noble metal supported catalyst.
Examples of the hydrogenation catalyst include, but are not limited to: (1) A supported heterogeneous hydrogenation catalyst comprising a metal such as Ni, pt, pd, ru supported on carbon, silica, alumina, diatomaceous earth or the like; (2) A so-called Ziegler-type hydrogenation catalyst using a reducing agent such as an organic acid salt such as Ni, co, fe, cr or a transition metal salt such as acetylacetonate and an organic aluminum; (3) An organometallic compound such as Ti, ru, rh, zr, and so-called organometallic complex. Further, examples of the hydrogenation catalyst include, but are not limited to, known hydrogenation catalysts described in Japanese patent publication No. 42-8704, japanese patent publication No. 43-6636, japanese patent publication No. 63-4841, japanese patent publication No. 1-37970, japanese patent publication No. 1-53851, japanese patent publication No. 2-9041, and Japanese patent application laid-open No. 8-109219. The hydrogenation catalyst is preferably a reaction mixture of a cyclopentadienyl titanium compound and a reducing organometallic compound.
(step of adding deactivator and neutralizer)
In the method for producing a branched conjugated diene polymer according to the present embodiment, an inactivating agent, a neutralizing agent, and the like may be added to the polymer solution as needed after the coupling step.
Examples of the inactivating agent include, but are not limited to, water; alcohols such as methanol, ethanol, and isopropanol; etc.
Examples of the neutralizing agent include, but are not limited to, carboxylic acids such as stearic acid, oleic acid, and neodecanoic acid (a mixture of 10-branched carboxylic acids having 9 to 11 carbon atoms); aqueous solution of inorganic acid, and carbon dioxide.
(step of adding stabilizer for rubber)
In the method for producing a branched conjugated diene polymer according to the present embodiment, it is preferable to add a rubber stabilizer in terms of preventing gel formation after polymerization and improving stability during processing.
As the stabilizer for rubber, a known stabilizer for rubber can be used, but is not limited thereto, and for example, antioxidants such as 2, 6-di-t-butyl-4-hydroxytoluene (hereinafter also referred to as "BHT"), n-octadecyl 3- (4 ' -hydroxy-3 ',5' -di-t-butylphenol) propionate, 2-methyl-4, 6-bis [ (octylthio) methyl ] phenol and the like are preferable.
(step of adding softener for rubber)
In the method for producing a branched conjugated diene polymer according to the present embodiment, a rubber softener may be added as needed in order to further improve the productivity of the branched conjugated diene polymer, the processability after the resin composition is produced by compounding a filler, and the like.
The softening agent for rubber is not particularly limited, and examples thereof include extender oil, liquid rubber, resin, and the like.
As a method of adding the softening agent for rubber to the branched conjugated diene polymer, the following method is preferable but not limited: the softening agent for rubber is added to the branched conjugated diene polymer solution, mixed to prepare a polymer solution containing the softening agent for rubber, and then desolventized.
Examples of the preferred extender oil include aromatic oil, naphthenic oil, paraffinic oil, and the like. Among these, from the viewpoint of environmental safety and prevention of oil bleeding and wet grip characteristics, a substitute aromatic oil having a polycyclic aromatic (PCA) component of 3 mass% or less based on the IP346 method is preferable. As the substitute aromatic oil, TDAE (treated distilled aromatic extract, treated Distillate Aromatic Extracts), MES (mild extracted solvate, mild Extraction Solvate) and the like shown in Kautschuk Gummi Kunststoffe (12) 799 (1999), and RAE (residual aromatic extract, residual Aromatic Extracts) can be cited.
The preferable liquid rubber is exemplified by, but not limited to, liquid polybutadiene, liquid styrene-butadiene rubber, and the like.
The effect of adding the liquid rubber may be: the processability of the resin composition obtained by blending the branched conjugated diene polymer, the filler and the like can be improved, and the glass transition temperature of the resin composition can be shifted to a low temperature side, whereby the abrasion resistance, low hysteresis loss and low temperature characteristics of the resin composition after the production of a sulfide can be improved.
Examples of the resin as the rubber softener include, but are not limited to, aromatic petroleum resins, coumarone-indene resins, terpene resins, rosin derivatives (including tung oil resins), tall oil derivatives, rosin ester resins, natural and synthetic terpene resins, aliphatic hydrocarbon resins, aromatic hydrocarbon resins, mixed aliphatic-aromatic hydrocarbon resins, coumarin-indene resins, phenol resins, p-tert-butylphenol-acetylene resins, phenol-formaldehyde resins, xylene-formaldehyde resins, oligomers of mono-olefins, oligomers of diolefins, aromatic hydrocarbon resins, aromatic petroleum resins, hydrogenated aromatic hydrocarbon resins, cyclic aliphatic hydrocarbon resins, hydrogenated hydrocarbon resins, hydrogenated tung oil resins, hydrogenated oil resins, esters of hydrogenated oil resins with mono-or polyfunctional alcohols, and the like. One kind of these resins may be used, or two or more kinds may be used in combination. In the case of hydrogenation, all unsaturated groups may be hydrogenated, or a part may remain.
The effect of adding the resin as the rubber softener includes: the processability of the resin composition obtained by blending the branched conjugated diene polymer, the filler and the like can be improved, the breaking strength after the production of the sulfide can be improved, and the glass transition temperature of the resin composition can be shifted to a high temperature side, whereby the wet skid resistance can be improved.
The amount of the filler oil, liquid rubber, resin, or the like to be added as the rubber softener is not particularly limited, but is preferably 1 to 60 parts by mass, more preferably 5 to 50 parts by mass, and still more preferably 10 to 37.5 parts by mass, relative to 100 parts by mass of the branched conjugated diene polymer obtained by the production method of the present embodiment.
When the rubber softener is added in the above range, the branched conjugated diene polymer obtained by the production method of the present embodiment, the filler and the like are blended to give a resin composition, and the resin composition tends to have good processability and good breaking strength and abrasion resistance after the production of a sulfide.
(desolventizing step)
In the method for producing a branched conjugated diene polymer according to the present embodiment, a known method can be used as a method for obtaining the obtained branched conjugated diene polymer from a polymer solution. The method is not particularly limited, and examples thereof include: separating the solvent by steam stripping and the like, filtering out the polymer, and further dehydrating and drying the polymer to obtain the polymer; concentrating by a flash tank, and further devolatilizing by an exhaust extruder or the like; a method of directly performing devolatilization using a drum dryer or the like.
[ rubber composition and Process for producing the same ]
The rubber composition of the present embodiment contains: a rubber component containing 10 mass% or more of the branched conjugated diene polymer produced by the production method of the present embodiment; and a filler in an amount of 5.0 to 150 parts by mass based on 100 parts by mass of the rubber component.
The method for producing a rubber composition according to the present embodiment comprises the following steps: a step of obtaining a branched conjugated diene polymer by the above-described production method; a step of obtaining a rubber component containing 10 mass% or more of the branched conjugated diene polymer; and a step of containing 5.0 to 150 parts by mass of a filler per 100 parts by mass of the rubber component.
Further, the branched conjugated diene polymer obtained by the production method of the present embodiment is preferably contained in the rubber component in an amount of 10% by mass, from the viewpoint of improving fuel economy, processability and abrasion resistance.
The filler preferably contains a silica-based inorganic filler.
In the rubber composition, the silica-based inorganic filler as the filler is dispersed, so that the processability in producing a vulcanized product tends to be more excellent, and the abrasion resistance, breaking strength, low hysteresis loss and wet skid resistance after producing a vulcanized product tend to be more excellent in balance.
The rubber composition preferably contains a silica-based inorganic filler even when used for a vulcanized rubber such as a tire, an automobile part such as a vibration damping rubber, or a shoe.
The rubber composition of the present embodiment is obtained by mixing the filler with a rubber component containing 10 mass% or more of the branched conjugated diene polymer obtained by the above-described production method.
The rubber component may contain a rubbery polymer other than the branched conjugated diene polymer (hereinafter simply referred to as "rubbery polymer").
Examples of the rubbery polymer include, but are not limited to, conjugated diene polymers or hydrogenated products thereof, random copolymers of conjugated diene compounds and vinyl aromatic compounds or hydrogenated products thereof, block copolymers of conjugated diene compounds and vinyl aromatic compounds or hydrogenated products thereof, non-diene polymers, and natural rubber.
Examples of the rubbery polymer include, but are not limited to, styrene-based elastomers such as butadiene rubber or its hydride, isoprene rubber or its hydride, styrene-butadiene block copolymer or its hydride, styrene-isoprene block copolymer or its hydride, and nitrile rubber or its hydride.
Examples of the non-diene polymer include, but are not limited to, olefin elastomers such as ethylene-propylene rubber, ethylene-propylene-diene rubber, ethylene-butene rubber, ethylene-hexene rubber, and ethylene-octene rubber, butyl rubber, brominated butyl rubber, acrylic rubber, fluororubber, silicone rubber, chlorinated polyethylene rubber, epichlorohydrin rubber, α, β -unsaturated nitrile-acrylate-conjugated diene copolymer rubber, urethane rubber, and polysulfide rubber.
Examples of the natural rubber include, but are not limited to, RSS3 to 5, SMR, and epoxidized natural rubber as a tobacco flake rubber.
The various rubbery polymers mentioned above may be modified rubbers to which polar functional groups such as hydroxyl groups and amino groups are added. In the case of use for tire applications, butadiene rubber, isoprene rubber, styrene-butadiene rubber, natural rubber, and butyl rubber are preferably used.
The weight average molecular weight of the rubbery polymer is preferably 2000 to 2000000, more preferably 5000 to 1500000, from the viewpoint of balance between various performances and processing characteristics of the resin composition. In addition, a rubbery polymer having a low molecular weight, so-called liquid rubber, may be used.
These rubbery polymers may be used alone in an amount of 1 or in an amount of 2 or more.
When the rubber composition containing the rubber-like polymer is produced from the rubber composition using the branched conjugated diene polymer obtained by the production method of the present embodiment, the content (mass ratio) of the branched conjugated diene polymer to the rubber-like polymer is preferably 10/90 to 100/0, more preferably 20/80 to 90/10, still more preferably 50/50 to 80/20 in terms of (branched conjugated diene polymer/rubber-like polymer).
Accordingly, the branched conjugated diene polymer is preferably contained in the rubber component in an amount of 10 to 100 mass%, more preferably 20 to 90 mass%, and even more preferably 50 to 80 mass%, based on the total amount (100 mass%) of the rubber component.
When the content ratio of the branched conjugated diene polymer/rubbery polymer is in the above range, the abrasion resistance after the production of a sulfide, the breaking strength, the low hysteresis loss and the wet skid resistance tend to be well balanced.
Examples of the filler included in the rubber composition include, but are not limited to, silica-based inorganic fillers, carbon black, metal oxides, and metal hydroxides. Among these, silica-based inorganic fillers are preferable.
The filler may be used alone or in combination of 1 or more than 2.
The filler content in the rubber composition is 5.0 parts by mass or more and 150 parts by mass or less, preferably 20 parts by mass or more and 100 parts by mass or less, more preferably 30 parts by mass or more and 90 parts by mass or less, relative to 100 parts by mass of the rubber component containing the branched conjugated diene polymer.
The filler content in the rubber composition is 5.0 parts by mass or more per 100 parts by mass of the rubber component in terms of exhibiting the effect of adding the filler, and 150 parts by mass or less per 100 parts by mass of the rubber component in terms of sufficiently dispersing the filler and sufficiently practically providing the processability and mechanical strength of the rubber composition.
The silica-based inorganic filler is not particularly limited, and a known one can be used, and preferably contains SiO 2 Or Si (or) 3 Solid particles containing Al as a structural unit, more preferably SiO 2 Or Si (or) 3 Solid particles having Al as a main component of the structural unit. The main component is a component contained in the silica-based inorganic filler in an amount of 50 mass% or more, preferably 70 mass% or more, and more preferably 80 mass% or more.
Examples of the silica-based inorganic filler include, but are not limited to, inorganic fibrous materials such as silica, clay, talc, mica, diatomaceous earth, wollastonite, montmorillonite, zeolite, and glass fiber. Further, a silica-based inorganic filler, a mixture of a silica-based inorganic filler and an inorganic filler other than silica-based, the surface of which is hydrophobized, may be mentioned.
Among these, silica and glass fibers are preferable, and silica is more preferable, from the viewpoints of strength, abrasion resistance, and the like.
Examples of the silicon oxide include dry silicon oxide, wet silicon oxide, and synthetic silicate silicon oxide. Among these silica, wet silica is preferable in terms of excellent balance between the effect of improving the breaking strength and the wet skid resistance.
In the rubber composition, the specific nitrogen adsorption surface area of the silica-based inorganic filler as determined by the BET adsorption method is preferably 100m in order to obtain practically good abrasion resistance and breaking strength 2 Per gram of 300m or more 2 Less than/g, more preferably 170m 2 Per gram of 250m or more 2 And/g or less.
In addition, if necessary, the specific surface area may be made relatively small (for example, the specific surface area is smaller than 200m 2 Silica-based inorganic filler of (g) having a relatively large specific surface area (for example, 200 m) 2 Per gram) or more) of a silica-based inorganic filler.
Particularly when a specific surface area is relatively large (e.g., 200m 2 Per g) or more), the rubber composition containing the branched conjugated diene polymer improves the dispersibility of silica, and particularly has an effect of improving abrasion resistance, and tends to be highly balanced with good breaking strength and low hysteresis loss.
The content of the silica-based inorganic filler in the rubber composition is preferably 5.0 parts by mass or more and 150 parts by mass or less, more preferably 20 parts by mass or more and 100 parts by mass or less, per 100 parts by mass of the rubber component containing the branched conjugated diene-based polymer obtained by the production method of the present embodiment. The content of the silica-based inorganic filler in the rubber composition is preferably 5.0 parts by mass or more per 100 parts by mass of the rubber component in view of exhibiting the effect of adding the silica-based inorganic filler, and 150 parts by mass or less per 100 parts by mass of the rubber component in view of sufficiently dispersing the silica-based inorganic filler and practically sufficiently improving the processability and mechanical strength of the rubber composition.
Examples of the carbon black include, but are not limited to, carbon black of various grades such as SRF, FEF, HAF, ISAF, SAF. Among these, a nitrogen adsorption specific surface area of 50m is preferable 2 Carbon black having a dibutyl phthalate (DBP) oil absorption of 80mL/100g or less.
The content of the carbon black in the rubber composition is preferably 0.5 parts by mass or more and 100 parts by mass or less, more preferably 3.0 parts by mass or more and 100 parts by mass or less, and still more preferably 5.0 parts by mass or more and 50 parts by mass or less, relative to 100 parts by mass of the rubber component containing the branched conjugated diene polymer obtained by the production method of the present embodiment. In the rubber composition, the content of carbon black is preferably 0.5 parts by mass or more relative to 100 parts by mass of the rubber component in view of exhibiting properties required for applications such as tires such as dry grip performance and electrical conductivity, and is preferably 100 parts by mass or less relative to 100 parts by mass of the rubber component in view of dispersibility.
The metal oxide means solid particles having a chemical formula MxOy (M represents a metal atom, x and y each independently represent an integer of 1 to 6) as a main component of the structural unit.
Examples of the metal oxide include, but are not limited to, aluminum oxide, titanium oxide, magnesium oxide, and zinc oxide.
Examples of the metal hydroxide include, but are not limited to, aluminum hydroxide, magnesium hydroxide, and zirconium hydroxide.
The method for producing a rubber composition of the present embodiment may contain a silane coupling agent.
The silane coupling agent has a function of compacting interaction between the rubber component and the inorganic filler, and has a group having affinity or binding property for the rubber component and the silica-based inorganic filler, respectively, and is preferably a compound having a sulfur bond moiety and an alkoxysilyl group or silanol group moiety in one molecule. Such a compound is not particularly limited, and examples thereof include bis- [3- (triethoxysilyl) -propyl ] -tetrasulfide, bis- [3- (triethoxysilyl) -propyl ] -disulfide, and bis- [2- (triethoxysilyl) -ethyl ] -tetrasulfide.
The content of the silane coupling agent in the rubber composition is preferably 0.1 part by mass or more and 30 parts by mass or less, more preferably 0.5 part by mass or more and 20 parts by mass or less, and still more preferably 1.0 part by mass or more and 15 parts by mass or less, based on 100 parts by mass of the inorganic filler. When the content of the silane coupling agent is within the above range, the above-described effect of addition by the silane coupling agent tends to be more remarkable.
The rubber composition may contain a rubber softener in order to improve its processability.
The amount of the rubber softener to be added is expressed by the total amount of the rubber softener to be added in the production of the rubber composition and the amount of the rubber softener to be previously contained in the branched conjugated diene polymer and other rubbery polymers per 100 parts by mass of the rubber component containing the branched conjugated diene polymer obtained by the production method of the present embodiment.
As softeners for rubber, mineral oils or liquid or low molecular weight synthetic softeners are suitable.
A mineral oil-based rubber softener called process oil or extender oil, which is used for softening, compatibilizing and improving the processability of rubber, is a mixture of an aromatic ring, a naphthene ring and a paraffin chain, wherein the paraffin chain has 50% or more of carbon atoms in all carbons is called a paraffin system, the naphthene ring has 30% or more and 45% or less of carbon atoms in all carbons is called a naphthene system, and the aromatic carbon atom has more than 30% of carbon atoms in all carbons is called an aromatic system. In the case where the conjugated diene polymer of the present embodiment is a copolymer of a conjugated diene compound and a vinyl aromatic compound, the rubber softener having a suitable aromatic content tends to have good fusion with the copolymer as the rubber softener to be used, and is therefore preferable.
The content of the softening agent for rubber in the rubber composition is preferably 0 to 100 parts by mass, more preferably 10 to 90 parts by mass, and still more preferably 30 to 90 parts by mass, based on 100 parts by mass of the rubber component. When the content of the softening agent for rubber is 100 parts by mass or less relative to 100 parts by mass of the rubber component, bleeding out and tackiness on the surface of the rubber composition can be suppressed.
Examples of the method for mixing the branched conjugated diene polymer obtained by the production method of the present embodiment with other additives such as a rubbery polymer, a silica-based inorganic filler, carbon black and other fillers, a silane coupling agent, and a rubber softener include, but are not limited to, melt kneading methods using a general mixer such as an open mill, a Banbury mixer, a kneader, a single-screw extruder, a twin-screw extruder, and a multi-screw extruder; and a method of dissolving and mixing the components and then heating to remove the solvent.
Among these, the melt kneading method using rolls, banbury mixer, kneader, or extruder is preferable in terms of productivity and excellent kneading property. In addition, any of a method of mixing the rubber component with other filler, silane coupling agent and additive at one time and a method of mixing the components in several times may be used.
The rubber composition can be prepared into a vulcanized composition which is vulcanized by a vulcanizing agent. Examples of the vulcanizing agent include, but are not limited to, radical initiators such as organic peroxides and azo compounds, oxime compounds, nitroso compounds, polyamine compounds, sulfur, and sulfur-containing compounds. The sulfur-containing compound includes sulfur monochloride, sulfur dichloride, a disulfide compound, a polymer polysulfide compound, and the like.
The content of the vulcanizing agent in the rubber composition is preferably 0.01 to 20 parts by mass, more preferably 0.1 to 15 parts by mass, based on 100 parts by mass of the rubber component. As the vulcanization method, a conventionally known method can be used, and the vulcanization temperature is preferably 120℃to 200℃and more preferably 140℃to 180 ℃.
In vulcanization, a vulcanization accelerator may be used as required. As the vulcanization accelerator, conventionally known materials can be used, and examples thereof include, but are not limited to, sulfenamide-based, guanidine-based, thiuram-based, aldehyde-amine-based, aldehyde-ammonia-based, thiazole-based, thiourea-based, and dithiocarbamate-based vulcanization accelerators. Examples of the vulcanization aid include, but are not limited to, zinc white and stearic acid. The content of the vulcanization accelerator is preferably 0.01 to 20 parts by mass, more preferably 0.1 to 15 parts by mass, based on 100 parts by mass of the rubber component.
In the rubber composition, various additives other than the above-described softeners and fillers, heat-resistant stabilizers, antistatic agents, weather-resistant stabilizers, age resisters, colorants, lubricants, and the like may be used within a range that does not impair the object of the present embodiment.
As the other softener, a known softener can be used.
Examples of the other filler include, but are not limited to, calcium carbonate, magnesium carbonate, aluminum sulfate, and barium sulfate. As the heat stabilizer, antistatic agent, weather stabilizer, aging inhibitor, colorant, and lubricant, known materials can be used.
Tire and method for producing tire
The tire of the present embodiment contains the rubber composition of the present embodiment described above.
The method for manufacturing a tire according to the present embodiment includes the steps of: a step of obtaining a branched conjugated diene polymer by the production method of the present embodiment; a step of obtaining a rubber composition containing the branched conjugated diene polymer; and a step of molding the rubber composition.
The rubber composition containing the branched conjugated diene polymer obtained by the production method of the present embodiment is suitable for use as a rubber composition for a tire.
The rubber composition for a tire can be used for, but not limited to, various tire tread, tire carcass, bead portion and other tire parts of various tires such as fuel-saving tires, all season tires, high performance tires, studless tires and the like. In particular, the rubber composition for tires is excellent in balance between abrasion resistance, breaking strength, low hysteresis loss and wet skid resistance after being formed into a vulcanizate, and therefore is suitable for use as a tread of a fuel-efficient tire or a high-performance tire.
Examples
The present embodiment will be described in more detail with reference to specific examples and comparative examples, but the present embodiment is not limited to the following examples and comparative examples.
[ example 1 ]
The physical properties of the examples and comparative examples [ example 1 ] were measured by the methods shown below.
Hereinafter, the conjugated diene polymer coupled with the nitrogen atom-containing modifier is described as "coupled conjugated diene polymer".
The conjugated diene polymer in an unmodified state is referred to as an "unmodified conjugated diene polymer".
The conjugated diene polymer having a branched structure is described as a "branched conjugated diene polymer".
(physical Properties 1) Mooney viscosity of Polymer
The Mooney viscosity was measured according to ISO 289 using an L-shaped rotor using a Mooney viscometer (trade name "VR1132" manufactured by Shimadzu corporation) as a sample of an unmodified conjugated diene polymer or a conjugated diene polymer coupled with a nitrogen atom-containing modifier (hereinafter also referred to as "conjugated diene polymer").
The measurement temperature was 110℃in the case of using an unmodified conjugated diene polymer as a sample, and 100℃in the case of using a conjugated diene polymer as a sample.
The sample was first preheated at the test temperature for 1 minute, after which the rotor was rotated at 2rpm, and the torque after 4 minutes was measured as the Mooney viscosity (ML (1+4) )。
(physical Property 2) Mooney stress relaxation Rate
The conjugated diene polymer was used as a sample, the Mooney viscosity was measured using an L-shaped rotor according to ISO 289, the rotation of the rotor was stopped immediately after the Mooney viscosity was measured using a Mooney viscometer (trade name "VR1132" manufactured by Shimadzu corporation), the torque was recorded at intervals of 0.1 seconds during the period of 1.6 seconds to 5 seconds after the stop in Mooney units, the torque was plotted as a double logarithm with respect to time (seconds), and the slope of the straight line at that time was obtained, and the absolute value was used as the Mooney stress relaxation rate (MSR).
(physical Property 3) degree of branching (Bn)
The branching degree (Bn) of the conjugated diene polymer was measured by GPC-light scattering measurement with a viscosity detector as follows.
The conjugated diene polymer was used as a sample, and measured using a Gel Permeation Chromatography (GPC) measuring apparatus (trade name "GPCmax VE-2001" manufactured by Malvern corporation) in which 3 columns each having a polystyrene gel as a filler were connected, using 3 detectors each having a light scattering detector, an RI detector, and a viscosity detector (trade name "TDA305" manufactured by Malvern corporation) connected in this order, and the absolute molecular weight was determined from the results of the light scattering detector and the RI detector, and the intrinsic viscosity was determined from the results of the RI detector and the viscosity detector, based on standard polystyrene.
Use of linear polymers as basis for intrinsic viscosity [ eta ]]=-3.883M 0.771 The shrinkage factor (g') was calculated as an intrinsic viscosity ratio corresponding to each molecular weight. In the formula, M represents an absolute molecular weight.
Thereafter, the branching degree (Bn) defined as g '=6bn/{ (bn+1) (bn+2) } is calculated using the resulting shrinkage factor (g').
The eluent used was tetrahydrofuran (hereinafter also referred to as "THF") containing 5mmol/L of triethylamine.
For the column, trade names "TSKgel G4000HXL", "TSKgel G5000HXL" manufactured by Tosoh corporation and "TSKgel G6000HXL" were used in connection.
20mg of a sample for measurement was dissolved in 10mL of THF to prepare a measurement solution, and 100. Mu.L of the measurement solution was poured into a GPC measurement apparatus, and measurement was performed at an oven temperature of 40℃and a THF flow rate of 1 mL/min.
(physical Property 4) molecular weight
< measurement condition 1>:
the weight average molecular weight (Mw), the number average molecular weight (Mn) and the molecular weight distribution (Mw/Mn) were determined based on a calibration curve obtained using standard polystyrene by measuring a chromatogram using an unmodified conjugated diene polymer or a conjugated diene polymer as a sample using a GPC measuring apparatus (trade name "HLC-8320GPC" manufactured by Tosoh Co., ltd.) to which 3 columns each having a polystyrene gel as a filler were connected and using an RI detector (trade name "HLC8020" manufactured by Tosoh Co., ltd.).
The eluent was THF (tetrahydrofuran) containing 5mmol/L of triethylamine. The column was used with 3 pieces of trade name "TSKgel SuperMultiporeHZ-H" manufactured by Tosoh corporation, and the trade name "TSK guard column SuperMP (HZ) -H" manufactured by Tosoh corporation as a guard column was connected to the front end of the column.
10mg of the measurement sample was dissolved in 10mL of THF to prepare a measurement solution, and 10. Mu.L of the measurement solution was poured into a GPC measurement apparatus, and measurement was performed under conditions of an oven temperature of 40℃and a THF flow rate of 0.35 mL/min.
Among the various samples to be measured under the above measurement condition 1, the samples having a molecular weight distribution (Mw/Mn) of less than 1.6 were reused under the following measurement condition 2. The measurement value obtained by the measurement under the measurement condition 1 was used for the sample having a molecular weight distribution value of 1.6 or more.
< measurement condition 2>:
the weight average molecular weight (Mw) and the number average molecular weight (Mn) were determined based on calibration curves obtained using standard polystyrene by measuring chromatograms using GPC measurement apparatuses in which 3 columns each containing a polystyrene gel as a filler were connected to an unmodified conjugated diene polymer or a conjugated diene polymer as a sample.
The eluent was THF containing 5mmol/L triethylamine. As regards the column, a protection column is used: trade name "TSK guard column SuperH-H", column manufactured by Tosoh Corp: trade names "TSKgel SuperH5000", "TSKgel SuperH6000", "TSKgel SuperH7000" manufactured by Tosoh corporation.
An RI detector (trade name "HLC8020" manufactured by Tosoh corporation) was used at an oven temperature of 40℃and a THF flow rate of 0.6 mL/min. 10mg of the measurement sample was dissolved in 20mL of THF to prepare a measurement solution, and 20. Mu.L of the measurement solution was poured into a GPC measurement apparatus to measure.
For the sample having a molecular weight distribution value of less than 1.6 measured under the measurement condition 1, the measurement was performed under the measurement condition 2.
(physical Property 5) modification ratio
The modification rate of the conjugated diene polymer was measured by the column adsorption GPC method as follows.
The measurement was performed by using the modified basic polymer component as a sample and by using the characteristic that the modified basic polymer component was adsorbed on a GPC column using silica gel as a filler.
The modification ratio was obtained by measuring the adsorption amount on a silica column from the difference between a chromatogram obtained by measuring a sample solution containing a sample and a low molecular weight internal standard polystyrene using a polystyrene column and a chromatogram obtained by measuring a silica column.
The details are as follows.
The sample having a molecular weight distribution value of 1.6 or more was measured under the measurement condition 1 described above (physical property 4), and was measured under the following measurement condition 3. The sample having a molecular weight distribution value of less than 1.6 was measured under the above-mentioned measurement condition 1 (physical property 4), and was measured under the following measurement condition 4.
< preparation of sample solution >:
a sample solution was prepared by dissolving 10mg of the sample and 5mg of standard polystyrene in 20mL of THF.
< measurement condition 3>:
GPC measurement conditions using polystyrene column:
using the trade name "HLC-8320GPC" manufactured by Tosoh corporation, THF containing 5mmol/L of triethylamine was used as an eluent, 10. Mu.L of the sample solution was injected into the apparatus, and a chromatogram was obtained using an RI detector under conditions of a column oven temperature of 40℃and a THF flow rate of 0.35 mL/min.
The column was used with 3 pieces of "TSKgel SuperMultiporeHZ-H" manufactured by Tosoh corporation and "TSK guard column SuperMP (HZ) -H" manufactured by Tosoh corporation as a guard column connected to the front end of the column.
< measurement condition 4>:
using THF containing 5mmol/L of triethylamine as an eluent, 20. Mu.L of a sample solution was injected into the apparatus for measurement.
As regards the column, a protection column is used: trade name "TSK guard column SuperH-H", column manufactured by Tosoh Corp: trade names "TSKgel SuperH5000", "TSKgel SuperH6000", "TSKgel SuperH7000" manufactured by Tosoh corporation. Measurement was performed using an RI detector (HLC 8020 manufactured by Tosoh corporation) at a temperature of 40℃in a chromatographic column incubator and a THF flow rate of 0.6 mL/min, to obtain a chromatogram.
GPC measurement conditions using silica-based column: using the trade name "HLC-8320GPC", manufactured by Tosoh corporation, THF was used as an eluent, 50. Mu.L of the sample solution was injected into the apparatus, and a chromatogram was obtained using an RI detector under conditions of a column oven temperature of 40℃and a THF flow rate of 0.5 ml/min. As the column, trade names "Zorbax PSM-1000S", "PSM-300S" and "PSM-60S" were used in connection, and trade names "DIOL 4.6X12.5 mm 5 mcron" as a guard column was used in connection with the front end thereof.
The modification rate calculation method comprises the following steps:
the modification ratio (%) was obtained by assuming that the entire peak area of the chromatogram using the polystyrene column was 100, the peak area of the sample was P1, the peak area of the standard polystyrene was P2, the entire peak area of the chromatogram using the silica column was 100, the peak area of the sample was P3, and the peak area of the standard polystyrene was P4.
Modification ratio (%) = [1- (p2×p3)/(p1×p4) ]×100
(wherein p1+p2=p3+p4=100)
(physical Property 6) amount of bound styrene
A measurement sample was prepared by dissolving 100mg of a conjugated diene polymer coupled without a rubber softener in 100mL of chloroform.
The amount of bound styrene (mass%) was measured as 100 mass% relative to the conjugated diene polymer as a sample by the amount of the phenyl group absorbed by the ultraviolet absorption wavelength (around 254 nm) (measuring device: spectrophotometer "UV-2450" manufactured by Shimadzu corporation).
(Property 7) microstructure of butadiene portion (1, 2-vinyl bond content)
A conjugated diene polymer coupled without a rubber softener was used as a sample, and 50mg of the sample was dissolved in 10mL of carbon disulfide to prepare a measurement sample.
Using a solution dish at 600-1000 cm -1 The microstructure of the butadiene portion, i.e., the 1, 2-vinyl bond content (mol%) was determined from the absorbance at a predetermined wavenumber by the calculation formula of Hampton method (R.R. Hampton, analytical Chemistry, 923 (1949)) (measuring apparatus: manufactured by Japanese spectroscopic Co., ltd.)Fourier transform Infrared Spectrophotometer "FT-IR 230").
Physical Property 8 molecular weight (absolute molecular weight) measured by GPC-light scattering method
The weight average molecular weight (Mw-i) (also referred to as "absolute molecular weight") was determined based on the solution viscosity and the light scattering method by measuring a chromatogram using a GPC-light scattering measuring apparatus in which 3 columns each of which uses a polystyrene gel as a filler were connected to a conjugated diene polymer as a sample.
The eluent was prepared using a mixed solution of tetrahydrofuran and triethylamine (THF in TEA: 5mL of triethylamine in 1L of tetrahydrofuran).
With respect to the column, the column will be protected: trade name "TSK guard column HHR-H" manufactured by Tosoh corporation and column: trade names "TSKgel G6000HHR", "TSKgel G5000HHR", "TSKgel G4000HHR" manufactured by Tosoh corporation are used in connection.
GPC-light scattering measurement apparatus (trade name "Viscotek TDAmax" manufactured by Malvern Co., ltd.) was used at oven temperature of 40℃and THF flow rate of 1.0 mL/min.
10mg of a sample for measurement was dissolved in 20mL of THF to prepare a measurement solution, and 200. Mu.L of the measurement solution was poured into a GPC measurement apparatus to measure.
[ branched conjugated diene Polymer ]
Example 1-1 conjugated diene polymer (sample 1-1)
A tank-type pressure vessel having a stirrer and a jacket for controlling temperature, which was a tank-type reactor having an internal volume of 10L, a ratio (L/D) of the height (L) to the diameter (D) of 4.0, an inlet at the bottom and an outlet at the top, was used as a polymerization reactor, and 2 stages thereof were connected.
1, 3-butadiene from which water had been removed in advance was mixed at 18.6 g/min, styrene at 10.0 g/min, and n-hexane at 175.2 g/min. N-butyllithium for inert treatment of mixed residual impurities was added at 0.103 mmol/min to a static mixer provided in the middle of a pipe for supplying the mixed solution to the inlet of the reactor, and then continuously supplied to the bottom of the reactor. Further, 2-bis (2-tetrahydrofuranyl) propane as a polar substance was fed at a rate of 0.081 mmol/min and n-butyllithium as a polymerization initiator was fed at a rate of 0.143 mmol/min to the bottom of the 1 st reactor vigorously mixed with a stirrer, and the internal temperature of the reactor was maintained at 67 ℃.
The polymer solution was continuously withdrawn from the top of the 1 st reactor, continuously fed to the bottom of the 2 nd reactor, continuously reacted at 70℃and further fed from the top of the 2 nd reactor to the static mixer. At the time of sufficiently stabilizing the polymerization, a trimethoxy (4-vinylphenyl) silane (abbreviated as "BS-1" in the table) was added as a branching agent from the bottom of the 2 nd reactor at a rate of 0.0190 mmol/min while copolymerizing 1, 3-butadiene with styrene, and polymerization reaction and branching reaction were carried out to obtain a conjugated diene polymer having a main chain branched structure.
The conjugated diene polymer solution before the addition of the coupling agent was further withdrawn in small amounts at the time of stabilization of the polymerization reaction and branching reaction, and an antioxidant (BHT) was added so as to be 0.2g per 100g of the polymer, followed by removal of the solvent, and the mooney viscosity at 110 ℃ and various molecular weights were measured. The physical properties are shown in Table 1.
Then, tetraethoxysilane (abbreviated as "A" in the table) as a coupling agent was continuously added to the polymer solution flowing out from the outlet of the reactor at a rate of 0.0480 mmol/min, and mixed using a static mixer to carry out a coupling reaction. At this time, the time until the addition of the coupling agent to the polymer solution flowing out of the outlet of the reactor was 4.8 minutes, the temperature was 68℃and the difference between the temperature in the polymerization step and the temperature before the addition of the coupling agent was 2 ℃. The conjugated diene polymer solution after the coupling reaction was extracted in a small amount, and an antioxidant (BHT) was added so as to be 0.2g per 100g of the polymer, followed by removal of the solvent, whereby the amount of bound styrene (physical property 6) and the microstructure of the butadiene portion (1, 2-vinyl binding amount: physical property 7) were measured. The measurement results are shown in Table 1.
Subsequently, an antioxidant (BHT) was continuously added to the polymer solution after the coupling reaction at 0.055 g/min (n-hexane solution) per 100g of the polymer to terminate the coupling reaction. Simultaneously with the antioxidant, SRAE oil (JOMO Process NC140 manufactured by JX daily ore energy company) was continuously added as a rubber softener in an amount of 25.0g relative to 100g of the polymer, and the mixture was mixed by a static mixer. The solvent was removed by stripping, and a coupled conjugated diene polymer having a 4-branched structure derived from a branching agent (hereinafter also referred to as "branching agent structure (1)") which is a compound represented by the following formula (1) and having a 3-branched star-shaped polymer structure derived from a coupling agent was obtained in a part of the main chain (sample 1-1).
The physical properties of sample 1-1 are shown in Table 1.
The structure of the conjugated diene polymer was identified by comparing the molecular weight measured by GPC with the branching degree measured by GPC with a viscometer, with respect to the polymer before addition of the branching agent, the polymer after addition of the branching agent, and the polymer in each step after addition of the coupling agent. The structure of each sample was identified in the same manner as follows.
[ chemical 41]
(in the formula (1), R 1 Represents any one selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, and an aryl group having 6 to 20 carbon atoms, and may have a branched structure in a part thereof.
X 1 Is a single bond or contains an organic group selected from any one of the group consisting of carbon, hydrogen, nitrogen, sulfur and oxygen.
Y 1 Represents any one selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, and a halogen atom. Y is Y 1 Each of which may be the same or different. )
Examples 1 to 2 conjugated diene polymers (samples 1 to 2)
A conjugated diene polymer having a 4-branched structure derived from the branching agent structure (1) and a 4-branched star-shaped polymer structure derived from the coupling agent in a part of the main chain was obtained in the same manner as in example 1-1, except that the coupling agent was changed from tetraethoxysilane to 1, 2-bis (triethoxysilyl) ethane (abbreviated as "B" in the table) and the amount thereof added was 0.0360 mmol/min (sample 1-2). The physical properties of samples 1-2 are shown in Table 1.
Examples 1 to 3 conjugated diene polymers (samples 1 to 3)
A conjugated diene polymer having a 4-branched structure derived from the branching agent structure (1) and a 4-branched star-shaped polymer structure derived from the coupling agent in a part of the main chain was obtained in the same manner as in example 1-1, except that the coupling agent was changed from tetraethoxysilane to 1, 3-bis (N, N-diglycidyl aminomethyl) cyclohexane (abbreviated as "C" in the table) and the amount added was 0.0360 mmol/min (sample 1-3). The physical properties of samples 1 to 3 are shown in Table 1.
Examples 1 to 4 conjugated diene polymers (samples 1 to 4)
A conjugated diene polymer (sample 1-4) having a 4-branched structure derived from the branching agent structure (1) and a 4-branched star-shaped polymer structure derived from the coupling agent in a part of the main chain was obtained in the same manner as in example 1-1, except that the coupling agent was changed from tetraethoxysilane to 2, 2-dimethoxy-1- (3-trimethoxysilylpropyl) -1-aza-2-silacyclopentane (abbreviated as "D" in the table) and the amount added was 0.0360 mmol/min. The physical properties of samples 1 to 4 are shown in Table 1.
Examples 1 to 5 conjugated diene polymers (samples 1 to 5)
A conjugated diene polymer having a 4-branched structure derived from the branching agent structure (1) and a 6-branched star-shaped polymer structure derived from the coupling agent in a part of the main chain was obtained in the same manner as in example 1-1, except that the coupling agent was changed from tetraethoxysilane to tris (3-trimethoxysilylpropyl) amine (abbreviated as "E" in the table) and the amount added was 0.0250 mmol/min (sample 1-5). The physical properties of samples 1 to 5 are shown in Table 1.
Examples 1 to 6 conjugated diene polymers (samples 1 to 6)
A conjugated diene polymer having a 4-branched structure derived from the branching agent structure (1) and an 8-branched star-shaped polymer structure derived from the coupling agent in a part of the main chain was obtained in the same manner as in example 1-1, except that the coupling agent was changed from tetraethoxysilane to tetrakis (3-trimethoxysilylpropyl) -1, 3-propanediol (abbreviated as "F" in the table) and the amount added was 0.0190 mmol/min (samples 1-6). The physical properties of samples 1 to 6 are shown in Table 1.
Examples 1 to 7 conjugated diene polymers (samples 1 to 7)
A conjugated diene polymer having a 4-branched structure derived from the branching agent structure (1) and an 8-branched star-shaped polymer structure derived from the coupling agent in a part of the main chain was obtained in the same manner as in example 1-1, except that the coupling agent was changed from tetraethoxysilane to tetrakis (3-trimethoxysilylpropyl) -1, 3-propanediol (abbreviated as "F" in the table) and the amount added was 0.0160 mmol/min (samples 1-7). The physical properties of samples 1 to 7 are shown in Table 1.
Examples 1 to 8 conjugated diene polymers (samples 1 to 8)
A conjugated diene polymer (sample 1-8) having a 4-branched structure derived from the branching agent structure (1) and an 8-branched star-shaped polymer structure derived from the coupling agent in the same manner as in example 1-1 was obtained, except that the addition rate of 1, 3-butadiene was changed from 18.6 g/min to 24.3 g/min, the addition rate of styrene was changed from 10.0 g/min to 4.3 g/min, the addition rate of 2, 2-bis (2-tetrahydrofuranyl) propane as the polar substance was changed from 0.081 mmol/min to 0.044 mmol/min, the coupling agent was changed from tetraethoxysilane to tetrakis (3-trimethoxysilylpropyl) -1, 3-propylenediamine (abbreviated as "F" in the table) and the addition amount was changed to 0.0160 mmol/min. Physical properties of samples 1 to 8 are shown in Table 1.
Examples 1 to 9 conjugated diene polymers (samples 1 to 9)
A conjugated diene polymer (sample 1-9) having a 4-branched structure derived from the branching agent structure (1) and an 8-branched star-shaped polymer structure derived from the coupling agent in a part of the main chain was obtained in the same manner as in example 1-1, except that the addition rate of 1, 3-butadiene was changed from 18.6 g/min to 17.1 g/min, the addition rate of styrene was changed from 10.0 g/min to 11.5 g/min, the addition rate of 2, 2-bis (2-tetrahydrofuranyl) propane as the polar substance was changed from 0.081 mmol/min to 0.089 mmol/min, the coupling agent was changed from tetraethoxysilane to tetrakis (3-trimethoxysilylpropyl) -1, 3-propylenediamine (abbreviated as "F" in the table), and the addition amount was changed to 0.0160 mmol/min. The physical properties of samples 1 to 9 are shown in Table 2.
Examples 1 to 10 conjugated diene polymers (samples 1 to 10)
A conjugated diene polymer (sample 1-10) having a 4-branched structure derived from the branching agent structure (1) and an 8-branched star-shaped polymer structure derived from the coupling agent in a part of the main chain was obtained in the same manner as in example 1-1, except that the addition rate of the polar substance 2, 2-bis (2-tetrahydrofuranyl) propane was changed from 0.081 mmol/min to 0.200 mmol/min, the coupling agent was changed from tetraethoxysilane to tetrakis (3-trimethoxysilylpropyl) -1, 3-propanediamine (abbreviated as "F" in the table), and the addition amount was changed to 0.0160 mmol/min. Physical properties of samples 1 to 10 are shown in Table 2.
Examples 1 to 11 conjugated diene polymers (samples 1 to 11)
A conjugated diene polymer (sample 1-11) having a 2-branched structure derived from the branching agent structure (1) and a 4-branched star-shaped polymer structure derived from the coupling agent in a part of the main chain was obtained in the same manner as in example 1-1, except that the branching agent was changed from trimethoxy (4-vinylphenyl) silane to dimethylmethoxy (4-vinylphenyl) silane (abbreviated as "BS-2" in the table), the addition amount was changed to 0.0350 mmol/min, the coupling agent was changed from tetraethoxysilane to 1, 2-bis (triethoxysilyl) ethane (abbreviated as "B" in the table), and the addition amount was changed to 0.0360 mmol/min. Physical properties of samples 1 to 11 are shown in Table 2.
Examples 1 to 12 conjugated diene polymers (samples 1 to 12)
A conjugated diene polymer (sample 1-12) having a 2-branched structure derived from the branching agent structure (1) in a part of the main chain and a 4-branched star-shaped polymer structure derived from the coupling agent was obtained in the same manner as in example 1-1, except that the branching agent was changed from trimethoxy (4-vinylphenyl) silane to dimethylmethoxy (4-vinylphenyl) silane (abbreviated as "BS-2" in the table), the addition amount was changed to 0.0350 mmol/min, the coupling agent was changed from tetraethoxysilane to 2, 2-dimethoxy-1- (3-trimethoxysilylpropyl) -1-aza-2-silacyclopentane (abbreviated as "D" in the table), and the addition amount was changed to 0.0360 mmol/min. Physical properties of samples 1 to 12 are shown in Table 2.
Examples 1 to 13 conjugated diene polymers (samples 1 to 13)
A conjugated diene polymer having a 2-branched structure derived from the branching agent structure (1) in a part of the main chain and an 8-branched star-shaped polymer structure derived from the coupling agent (samples 1 to 13) was obtained in the same manner as in example 1-1, except that the branching agent was changed from trimethoxy (4-vinylphenyl) silane to dimethylmethoxy (4-vinylphenyl) silane (abbreviated as "BS-2" in the table), the addition amount was changed to 0.0350 mmol/min, the coupling agent was changed from tetraethoxysilane to tetrakis (3-trimethoxysilylpropyl) -1, 3-propanediamine (abbreviated as "F" in the table), and the addition amount was changed to 0.0160 mmol/min. Physical properties of samples 1 to 13 are shown in Table 2.
Examples 1 to 14 conjugated diene polymers (samples 1 to 14)
A conjugated diene polymer (sample 1-14) having a 3-branched structure derived from a compound represented by the following formula (2) (hereinafter also referred to as "branching agent structure (2)") and a 4-branched star-shaped polymer structure derived from a coupling agent was obtained in the same manner as in example 1-1 except that the branching agent was changed from trimethoxy (4-vinylphenyl) silane to 1, 1-bis (4- (dimethylmethoxysilyl) phenyl) ethylene (hereinafter also referred to as "BS-3"), the amount of the branching agent added was changed to 0.0120 mmol/min, the amount of the branching agent added was changed from tetraethoxysilane to 1, 2-bis (triethoxysilyl) ethane (hereinafter also referred to as "B"), and the amount of the branching agent added was changed to 0.0360 mmol/min. Physical properties of samples 1 to 14 are shown in Table 2.
[ chemical 42]
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(in the formula (2), X 2 、X 3 Is a single bond or contains an organic group selected from any one of the group consisting of carbon, hydrogen, nitrogen, sulfur and oxygen.
Y 2 、Y 3 Represents any one selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, and a halogen atom. Y is Y 2 、Y 3 Each of which may be the same or different. )
Examples 1 to 15 conjugated diene polymers (samples 1 to 15)
A conjugated diene polymer (sample 1-15) having a 3-branched structure derived from the branching agent structure (2) and a 4-branched star-shaped polymer structure derived from the coupling agent was obtained in the same manner as in example 1-1, except that the branching agent was changed from trimethoxy (4-vinylphenyl) silane to 1, 1-bis (4- (dimethylmethoxysilyl) phenyl) ethylene (abbreviated as "BS-3" in the table), the amount of the branching agent added was changed to 0.0120 mmol/min, the coupling agent was changed from tetraethoxysilane to 2, 2-dimethoxy-1- (3-trimethoxysilylpropyl) -1-aza-2-silacyclopentane (abbreviated as "D" in the table), and the amount of the branching agent added was changed to 0.0360 mmol/min. Physical properties of samples 1 to 15 are shown in Table 2.
Examples 1 to 16 conjugated diene polymers (samples 1 to 16)
A conjugated diene polymer (samples 1 to 16) having a 3-branched structure derived from the branching agent structure (2) in a part of the main chain and an 8-branched star-shaped polymer structure derived from the coupling agent was obtained in the same manner as in example 1-1, except that the branching agent was changed from trimethoxy (4-vinylphenyl) silane to 1, 1-bis (4- (dimethylmethoxysilyl) phenyl) ethylene (abbreviated as "BS-3" in the table), the amount of the branching agent added was changed to 0.0120 mmol/min, the coupling agent was changed from tetraethoxysilane to tetrakis (3-trimethoxysilylpropyl) -1, 3-propanediol (abbreviated as "F" in the table), and the amount of the branching agent added was changed to 0.0160 mmol/min. Physical properties of samples 1 to 16 are shown in Table 2.
Examples 1 to 17 conjugated diene polymers (samples 1 to 17)
A conjugated diene polymer (samples 1 to 17) having a 7-branched structure derived from the branching agent structure (2) and a 4-branched star-shaped polymer structure derived from the coupling agent in a part of the main chain was obtained in the same manner as in example 1-1, except that the branching agent was changed from trimethoxy (4-vinylphenyl) silane to 1, 1-bis (4-trimethoxysilylphenyl) ethylene (abbreviated as "BS-4" in the table), the addition amount was changed to 0.0210 mmol/min, the coupling agent was changed from tetraethoxysilane to 1, 2-bis (triethoxysilyl) ethane (abbreviated as "B" in the table), and the addition amount was changed to 0.0360 mmol/min. Physical properties of samples 1 to 17 are shown in Table 3.
Examples 1 to 18 conjugated diene polymers (samples 1 to 18)
A conjugated diene polymer having a 7-branched structure derived from the branching agent structure (2) and a 4-branched star-shaped polymer structure derived from the coupling agent (samples 1 to 18) was obtained in the same manner as in example 1-1, except that the branching agent was changed from trimethoxy (4-vinylphenyl) silane to 1, 1-bis (4-trimethoxysilylphenyl) ethylene (abbreviated as "BS-4" in the table), the amount of the branching agent added was changed to 0.0210 mmol/min, the coupling agent was changed from tetraethoxysilane to 2, 2-dimethoxy-1- (3-trimethoxysilylpropyl) -1-aza-2-silacyclopentane (abbreviated as "D" in the table), and the amount of the branching agent added was changed to 0.0360 mmol/min. Physical properties of samples 1 to 18 are shown in Table 3.
Examples 1 to 19 conjugated diene polymers (samples 1 to 19)
A conjugated diene polymer (samples 1 to 19) having a 7-branch structure derived from the branching agent structure (2) and an 8-branch star-shaped polymer structure derived from the coupling agent in a part of the main chain was obtained in the same manner as in example 1-1, except that the branching agent was changed from trimethoxy (4-vinylphenyl) silane to 1, 1-bis (4-trimethoxysilylphenyl) ethylene (abbreviated as "BS-4" in the table), the addition amount was changed to 0.0210 mmol/min, the coupling agent was changed from tetraethoxysilane to tetrakis (3-trimethoxysilylpropyl) -1, 3-propanediamine (abbreviated as "F" in the table), and the addition amount was changed to 0.0160 mmol/min. The physical properties of samples 1 to 19 are shown in Table 3.
Examples 1 to 20 conjugated diene polymers (samples 1 to 20)
A conjugated diene polymer (sample 1-20) having a 4-branched structure derived from the branching agent structure (1) and an 8-branched star-shaped polymer structure derived from the coupling agent in a part of the main chain was obtained in the same manner as in example 1-1, except that the branching agent was changed from trimethoxy (4-vinylphenyl) silane to trichloro (4-vinylphenyl) silane (abbreviated as "BS-5" in the table), the amount of the branching agent added was changed to 0.0190 mmol/min, the coupling agent was changed from tetraethoxysilane to 1, 2-bis (triethoxysilyl) ethane (abbreviated as "B" in the table), and the amount of the branching agent added was changed to 0.0360 mmol/min. Physical properties of the samples 1 to 20 are shown in Table 3.
Examples 1 to 21 conjugated diene polymers (samples 1 to 21)
A conjugated diene polymer (sample 1-21) having a 4-branched structure derived from the branching agent structure (1) and an 8-branched star-shaped polymer structure derived from the coupling agent was obtained in the same manner as in example 1-1, except that the branching agent was changed from trimethoxy (4-vinylphenyl) silane to trichloro (4-vinylphenyl) silane (abbreviated as "BS-5" in the table), the addition amount was changed to 0.0190 mmol/min, the coupling agent was changed from tetraethoxysilane to 2, 2-dimethoxy-1- (3-trimethoxysilylpropyl) -1-aza-2-silacyclopentane (abbreviated as "D" in the table), and the addition amount was changed to 0.0360 mmol/min. Physical properties of samples 1 to 21 are shown in Table 3.
Examples 1 to 22 conjugated diene polymers (samples 1 to 22)
A conjugated diene polymer (samples 1 to 22) having a 4-branched structure derived from the branching agent structure (1) and an 8-branched star-shaped polymer structure derived from the coupling agent in a part of the main chain was obtained in the same manner as in example 1-1, except that the branching agent was changed from trimethoxy (4-vinylphenyl) silane to trichloro (4-vinylphenyl) silane (abbreviated as "BS-5" in the table), the amount of the branching agent added was changed to 0.0190 mmol/min, the coupling agent was changed from tetraethoxysilane to tetrakis (3-trimethoxysilylpropyl) -1, 3-propanediamine (abbreviated as "F" in the table), and the amount of the branching agent added was changed to 0.0160 mmol/min. The physical properties of samples 1 to 22 are shown in Table 3.
Examples 1 to 23 conjugated diene polymers (samples 1 to 23)
A conjugated diene polymer (samples 1 to 23) having a 4-branched structure derived from the branching agent structure (1) and an 8-branched star-shaped polymer structure derived from the coupling agent in a part of the main chain was obtained in the same manner as in example 1-1, except that the amount of trimethoxy (4-vinylphenyl) silane (abbreviated as "BS-1" in the table) as the branching agent was changed from 0.0190 mmol/min to 0.0100 mmol/min, the amount of the coupling agent was changed from tetraethoxysilane to tetrakis (3-trimethoxysilylpropyl) -1, 3-propanediamine (abbreviated as "F" in the table) and the amount of the coupling agent was changed to 0.0190 mmol/min. Physical properties of samples 1 to 23 are shown in Table 3.
Examples 1 to 24 conjugated diene polymers (samples 1 to 24)
A conjugated diene polymer (sample 1-24) having a 4-branched structure derived from the branching agent structure (1) in a part of the main chain and an 8-branched star-shaped polymer structure derived from the coupling agent was obtained in the same manner as in example 1-1, except that the amount of trimethoxy (4-vinylphenyl) silane (abbreviated as "BS-1" in the table) as the branching agent was changed from 0.0190 mmol/min to 0.0250 mmol/min, the amount of the coupling agent was changed from tetraethoxysilane to tetrakis (3-trimethoxysilylpropyl) -1, 3-propanediamine (abbreviated as "F" in the table) and the amount of the coupling agent was changed to 0.0190 mmol/min. The physical properties of samples 1 to 24 are shown in Table 4.
Examples 1 to 25 conjugated diene polymers (samples 1 to 25)
A conjugated diene polymer (sample 1-25) having a 4-branched structure derived from the branching agent structure (1) in a part of the main chain and an 8-branched star-shaped polymer structure derived from the coupling agent was obtained in the same manner as in example 1-1, except that the amount of trimethoxy (4-vinylphenyl) silane (abbreviated as "BS-1" in the table) as the branching agent was changed from 0.0190 mmol/min to 0.0350 mmol/min, the amount of the coupling agent was changed from tetraethoxysilane to tetrakis (3-trimethoxysilylpropyl) -1, 3-propanediamine (abbreviated as "F" in the table) and the amount of the coupling agent was changed to 0.0190 mmol/min. The physical properties of samples 1 to 25 are shown in Table 4.
Examples 1 to 26 conjugated diene polymers (samples 1 to 26)
A conjugated diene polymer (sample 1-26) having a 4-branched structure derived from the branching agent structure (1) and an 8-branched star-shaped polymer structure derived from the coupling agent in a part of the main chain was obtained in the same manner as in example 1-1, except that the coupling agent was changed from tetraethoxysilane to tetrakis (3-trimethoxysilylpropyl) -1, 3-propanediol (abbreviated as "F" in the table) and the amount thereof was changed to 0.0190 mmol/min, and the SRAE oil added as a softener for rubber was changed to liquid rubber (liquid polybutadiene LBR-302 manufactured by KURARAY Co.). The physical properties of samples 1 to 26 are shown in Table 4.
Examples 1 to 27 conjugated diene polymers (samples 1 to 27)
A conjugated diene polymer having a 4-branched structure derived from the branching agent structure (1) and an 8-branched star-shaped polymer structure derived from the coupling agent in a part of the main chain was obtained in the same manner as in example 1-1 (samples 1-27), except that the coupling agent was changed from tetraethoxysilane to tetrakis (3-trimethoxysilylpropyl) -1, 3-propanediol (abbreviated as "F" in the table) and the amount thereof was changed to 0.0190 mmol/min, and the SRAE oil added as the rubber softener was changed to a Resin (terpene Resin YS Resin PX1250 manufactured by YASUHARA CHEMICAL). The physical properties of samples 1 to 27 are shown in Table 4.
Examples 1 to 28 conjugated diene polymers (samples 1 to 28)
A conjugated diene polymer having a 4-branched structure derived from the branching agent structure (1) and an 8-branched star-shaped polymer structure derived from the coupling agent in a part of the main chain (samples 1 to 28) was obtained in the same manner as in example 1-1, except that the coupling agent was changed from tetraethoxysilane to tetrakis (3-trimethoxysilylpropyl) -1, 3-propanediol (abbreviated as "F" in the table) and the amount thereof was changed to 0.0190 mmol/min, and the SRAE oil added as the rubber softener was changed to a cycloparaffin oil (cycloparaffin oil Nytex810 manufactured by Nynas). The physical properties of samples 1 to 28 are shown in Table 4.
Examples 1 to 29 conjugated diene polymers (samples 1 to 29)
A conjugated diene polymer having a 4-branched structure derived from the branching agent structure (1) and an 8-branched star-shaped polymer structure derived from the coupling agent in a part of the main chain was obtained in the same manner as in example 1-1, except that the coupling agent was changed from tetraethoxysilane to tetrakis (3-trimethoxysilylpropyl) -1, 3-propanediol (abbreviated as "F" in the table) and the amount of the coupling agent added was 0.0190 mmol/min and no rubber softener was added (samples 1-29). The physical properties of samples 1 to 29 are shown in Table 4.
Examples 1 to 30 conjugated diene polymers (samples 1 to 30)
A conjugated diene polymer having a 4-branched structure derived from the branching agent structure (1) and an 8-branched star-shaped polymer structure derived from the coupling agent in a part of the main chain (samples 1 to 30) was obtained in the same manner as in example 1-1 except that the coupling agent was changed from tetraethoxysilane to tetrakis (3-trimethoxysilylpropyl) -1, 3-propanediol (abbreviated as "F" in the table) and the amount of the added polymer was changed to 0.0190 mmol/min and the amount of the SRAE oil added as a rubber softener relative to 100g of the polymer was changed from 25.0g to 37.5 g. The physical properties of samples 1 to 30 are shown in Table 4.
Examples 1 to 31 conjugated diene polymers (samples 1 to 31)
A conjugated diene polymer having a 4-branched structure derived from the branching agent structure (1) in a part of the main chain and showing no star-shaped coupling structure derived from the coupling agent was obtained in the same manner as in example 1-1 except that trimethoxy (4-vinylphenyl) silane (abbreviated as "BS-1" in the table) was added as the branching agent from the bottom of the 2 nd reactor at a rate of 0.0190 mmol/min at the time of sufficiently stabilizing the polymerization (samples 1-31). The physical properties of samples 1 to 31 are shown in Table 5.
Examples 1 to 32 conjugated diene polymers (samples 1 to 32)
A conjugated diene polymer (sample 1-32) having a 4-branched structure derived from the branching agent structure (1) and a 3-branched star-shaped polymer structure derived from the coupling agent was obtained in the same manner as in example 1-1, except that trimethoxy (4-vinylphenyl) silane (abbreviated as "BS-1" in the table) was added as the branching agent from the bottom of the 2 nd reactor at a rate of 0.0190 mmol/min and the amount of tetraethoxysilane (abbreviated as "A" in the table) added as the coupling agent was changed from 0.0480 mmol/min to 0.0120 mmol/min at the time of sufficiently stabilizing the polymerization. The physical properties of samples 1 to 32 are shown in Table 5.
Examples 1 to 33 conjugated diene polymers (samples 1 to 33)
A conjugated diene polymer having a 4-branched structure derived from the branching agent structure (1) and a 8-branched star-shaped polymer structure derived from the coupling agent (samples 1 to 33) was obtained in the same manner as in example 1-1, except that trimethoxy (4-vinylphenyl) silane (abbreviated as "BS-1" in the table) was added as a branching agent from the bottom of the 2 nd reactor at a rate of 0.0190 mmol/min at the time of sufficiently stabilizing the polymerization, and the amount added was changed to 0.0038 mmol/min from tetraethoxysilane to tetrakis (3-trimethoxysilylpropyl) -1, 3-propanediamine (abbreviated as "F" in the table) as a coupling agent. The physical properties of samples 1 to 33 are shown in Table 5.
Examples 1 to 34 conjugated diene polymers (samples 1 to 34)
A conjugated diene polymer having a 2-branched structure derived from the branching agent structure (1) and a 3-branched star-shaped polymer structure derived from the coupling agent was obtained in the same manner as in example 1-1 except that dimethylmethoxy (4-vinylphenyl) silane (abbreviated as "BS-2" in the table) was added as the branching agent from the bottom of the 2 nd reactor at a rate of 0.0350 mmol/min and the amount of tetraethoxysilane added as the coupling agent was changed from 0.0480 mmol/min to 0.0120 mmol/min at the time of sufficiently stabilizing the polymerization (samples 1-34). The physical properties of samples 1 to 34 are shown in Table 5.
Examples 1 to 35 conjugated diene polymers (samples 1 to 35)
A conjugated diene polymer having a 3-branched structure derived from the branching agent structure (2) and a partial 3-branched star-shaped polymer structure derived from the coupling agent was obtained in the same manner as in example 1-1 except that 1, 1-bis (4- (dimethylmethoxysilyl) phenyl) ethylene (abbreviated as "BS-3" in the table) was added as the branching agent from the bottom of the 2 nd reactor at a rate of 0.0120 mmol/min at a time point when the polymerization was sufficiently stabilized, and the amount of tetraethoxysilane as the coupling agent was changed from 0.0480 mmol/min to 0.0120 mmol/min. The physical properties of samples 1 to 35 are shown in Table 5.
Examples 1 to 36 conjugated diene polymers (samples 1 to 36)
A conjugated diene polymer having a 4-branched structure derived from the branching agent structure (1) and a 2-branched star-shaped polymer structure derived from the coupling agent in a part of the main chain was obtained in the same manner as in example 1-1, except that the coupling agent was changed from tetraethoxysilane to 3- (benzylideneamino) propyltriethoxysilane (abbreviated as "G" in the table) and the amount added was 0.0620 mmol/min (samples 1-36). The physical properties of samples 1 to 36 are shown in Table 5.
Examples 1 to 37 conjugated diene polymers (samples 1 to 37)
A conjugated diene polymer having a 4-branched structure derived from the branching agent structure (1) and a 4-branched star-shaped polymer structure derived from the coupling agent in a part of the main chain (samples 1 to 37) was obtained in the same manner as in example 1-1, except that 1, 3-butadiene added to the 1 st reactor was changed from 18.6 g/min to 13.95 g/min and 4.65 g/min of 1, 3-butadiene was added simultaneously with the branching agent from the bottom of the 2 nd reactor. The physical properties of samples 1 to 37 are shown in Table 5.
Comparative examples 1-1 conjugated diene polymers (samples 1-38)
A tank-type pressure vessel having a stirrer and a jacket for controlling temperature, which was a tank-type reactor having an internal volume of 10L, a ratio (L/D) of the height (L) to the diameter (D) of 4.0, an inlet at the bottom and an outlet at the top, was used as a polymerization reactor, and 2 stages thereof were connected.
1, 3-butadiene from which water had been removed in advance was mixed at 18.6 g/min, styrene at 10.0 g/min, and n-hexane at 175.2 g/min. N-butyllithium for inert treatment of mixed residual impurities was added at 0.103 mmol/min to a static mixer provided in the middle of a pipe for supplying the mixed solution to the inlet of the reactor, and then continuously supplied to the bottom of the reactor. Further, 2-bis (2-tetrahydrofuranyl) propane as a polar substance was fed at a rate of 0.081 mmol/min and n-butyllithium as a polymerization initiator was fed at a rate of 0.143 mmol/min to the bottom of the 1 st reactor vigorously mixed with a stirrer, and the internal temperature of the reactor was maintained at 67 ℃.
The polymer solution was continuously withdrawn from the top of the 1 st reactor, continuously fed to the bottom of the 2 nd reactor, continuously reacted at 70℃and further fed from the top of the 2 nd reactor to the static mixer. At the time of sufficiently stabilizing the polymerization, the polymer solution before the addition of the coupling agent was withdrawn in a small amount, an antioxidant (BHT) was added so as to be 0.2g per 100g of the polymer, and then the solvent was removed, and the mooney viscosity at 110 ℃ and various molecular weights were measured. The physical properties are shown in Table 6.
Then, tetraethoxysilane (abbreviated as "A" in the table) as a coupling agent was continuously added to the polymer solution flowing out from the outlet of the reactor at a rate of 0.0480 mmol/min, and mixed using a static mixer to carry out a coupling reaction. At this time, the time until the addition of the coupling agent to the polymer solution flowing out of the outlet of the reactor was 4.8 minutes, the temperature was 68℃and the difference between the temperature in the polymerization step and the temperature before the addition of the coupling agent was 2 ℃. The conjugated diene polymer solution after the coupling reaction was extracted in a small amount, and an antioxidant (BHT) was added so as to be 0.2g per 100g of the polymer, followed by removal of the solvent, whereby the amount of bound styrene (physical property 6) and the microstructure of the butadiene portion (1, 2-vinyl binding amount: physical property 7) were measured. The measurement results are shown in Table 6.
Subsequently, an antioxidant (BHT) was continuously added to the polymer solution after the coupling reaction at 0.055 g/min (n-hexane solution) per 100g of the polymer to terminate the coupling reaction. Simultaneously with the antioxidant, SRAE oil (JOMO Process NC140 manufactured by JX daily ore energy company) was continuously added as a rubber softener in an amount of 25.0g relative to 100g of the polymer, and the mixture was mixed by a static mixer. The solvent was removed by stripping to obtain a conjugated diene polymer coupled with no main chain branch derived from the branching agent and with a 3-branched star-shaped polymer structure derived from the coupling agent (samples 1 to 38). The physical properties of samples 1 to 38 are shown in Table 6.
Comparative examples 1 to 2 conjugated diene polymers (samples 1 to 39)
A conjugated diene polymer having a 4-branched star-shaped polymer structure derived from a coupling agent was obtained in the same manner as in comparative example 1-1 except that the coupling agent was changed from tetraethoxysilane to 2, 2-dimethoxy-1- (3-trimethoxysilylpropyl) -1-aza-2-silacyclopentane (abbreviated as "D" in the table) and the amount added was 0.0360 mmol/min. The physical properties of samples 1 to 39 are shown in Table 6.
Comparative examples 1 to 3 conjugated diene polymers (samples 1 to 40)
A conjugated diene polymer having an 8-branched star-shaped polymer structure derived from a coupling agent was obtained in the same manner as in comparative example 1-1 except that the coupling agent was changed from tetraethoxysilane to tetrakis (3-trimethoxysilylpropyl) -1, 3-propanediamine (abbreviated as "F" in the table) and the amount added was 0.0190 mmol/min. The physical properties of samples 1 to 40 are shown in Table 6.
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(examples 1-38 to 1-74 and comparative examples 1-4 to 1-6)
The rubber compositions containing the respective raw material rubbers were obtained in the following proportions using the samples 1-1 to 1-40 shown in tables 1 to 6 as the raw material rubbers.
(rubber component)
Branched conjugated diene polymer and conjugated diene polymer (samples 1-1 to 1-40): 80 parts by mass (parts by mass of softener for removing rubber)
High cis polybutadiene (trade name "ube pol BR150" manufactured by yu division): 20 parts by mass (mixing condition)
The amount of each compound to be added is expressed in terms of parts by mass relative to 100 parts by mass of the rubber component containing no rubber softener.
Silica 1 (trade name "Ultrasil 7000GR" nitrogen adsorption specific surface area 170m manufactured by Evonik Degussa Co., ltd.) 2 /g): 50.0 parts by mass
Silicon oxide 2 (trade name "Zeosil Premium 200MP" manufactured by Rhodia Co., ltd.) nitrogen adsorption specific surface area 220m 2 /g): 25.0 parts by mass
Carbon black (trade name "sea KH (N339)", manufactured by eastern sea carbon company): 5.0 parts by mass
Silane coupling agent (trade name "Si75", bis (triethoxysilylpropyl) disulfide manufactured by Evonik Degussa corporation): 6.0 parts by mass
SRAE oil (trade name "Process NC140" manufactured by JX daily ore energy company): 42.0 parts by mass (including the amount added in advance in the form of the softener for rubber contained in samples 1-1 to 1-40)
Zinc white: 2.5 parts by mass
Stearic acid: 1.0 part by mass
Age resistor (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-benzooxazolylsulfenamide): 1.7 parts by mass
Vulcanization accelerator 2 (diphenylguanidine): 2.0 parts by mass
Summation of: 239.4 parts by mass
(kneading method)
The above materials were kneaded by the following method to obtain a rubber composition. The raw rubber (samples 1-1 to 1-40), the filler (silica 1, silica 2, carbon black), the silane coupling agent, the SRAE oil, the zinc white and the stearic acid were kneaded under the conditions of a filling rate of 65% and a rotor rotation speed of 30 to 50rpm using a closed kneader (content 0.3L) equipped with a temperature controller as a first stage of kneading. At this time, the temperature of the closed mixer was controlled, and each rubber composition (compound) was obtained under the condition that the discharge temperature was 155 to 160 ℃.
Next, as the second-stage kneading, the compound obtained above was cooled to room temperature, and then an anti-aging agent was added thereto, and kneading was performed again to improve the dispersion of the silica. In this case, the discharge temperature of the compound was also adjusted to 155 to 160 ℃ by temperature control of the mixer.
After cooling, sulfur and vulcanization accelerators 1 and 2 were added to an open mill set at 70℃as the third stage of kneading, and kneaded.
Thereafter, molding was performed, and vulcanization was performed at 160℃for 20 minutes using a vulcanization press.
The rubber composition before vulcanization and the rubber composition after vulcanization were evaluated. Specifically, the evaluation was performed by the following method. The results are shown in tables 7 to 12.
[ evaluation of Properties ]
(evaluation 1) Mooney viscosity of compound
The compound obtained in the above was used as a sample after the second stage kneading and before the third stage kneading, and after preheating at 130℃for 1 minute according to ISO 289, the rotor was rotated for 4 minutes at 2 revolutions per minute, and the viscosity was measured. The results of comparative examples 1 to 4 were normalized to 100. The smaller the index, the better the processability.
(evaluation 2) tensile Strength and elongation at break
The tensile strength and elongation at break were measured according to the tensile test method of JIS K6251, and the results of comparative examples 1 to 4 were set to 100 to carry out indexing. The larger the index, the better the tensile strength and elongation at break (breaking strength).
(evaluation 3) abrasion resistance
The abrasion amounts of the load of 44.4N and 1000 revolutions were measured in accordance with JIS K6264-2 using an AKRON abrasion tester (manufactured by An Tian Seiko Co., ltd.) and the results of comparative examples 1 to 4 were normalized to 100. The larger the index, the better the abrasion resistance.
(evaluation 4) viscoelasticity parameter
Viscoelasticity parameters were measured in torsional mode using the viscoelasticity tester "ARES" manufactured by Rheometric Scientific company. The results of the rubber compositions of comparative examples 1 to 4 were set to 100, and the measured values were indexed.
Tan delta measured at 0℃under conditions of a frequency of 10Hz and a deformation of 1% was used as an index of the wet grip performance. The larger the index, the better the wet grip.
Further, tan δ measured at 50 ℃ under the conditions of a frequency of 10Hz and a deformation of 3% was used as an index of fuel economy. The smaller the index, the better the fuel economy.
The elastic modulus (G') measured at 50℃under the conditions of a frequency of 10Hz and a deformation of 3% was used as an index of the steering stability. The larger the index, the better the steering stability.
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As shown in tables 7 to 12, it was confirmed that the compounds of examples 1 to 38 to 1 to 74 were low in mooney viscosity, exhibited good workability, were excellent in abrasion resistance, handling stability and breaking strength after the production of sulfides, and were excellent in balance between low hysteresis loss and wet skid resistance, as compared with comparative examples 1 to 4 to 1 to 6.
[ example 2 ]
The physical properties of the examples and comparative examples [ example 2 ] were measured by the methods shown below.
Hereinafter, the conjugated diene polymer coupled with the nitrogen atom-containing modifier composed of a specific compound is described as "coupled conjugated diene polymer".
The conjugated diene polymer in an unmodified state is referred to as an "unmodified conjugated diene polymer".
The conjugated diene polymer having a branched structure is described as a "branched conjugated diene polymer".
(physical Properties 1) Mooney viscosity of Polymer
The Mooney viscosity was measured according to ISO 289 using an L-shaped rotor using a Mooney viscometer (trade name "VR1132" manufactured by Shimadzu corporation) as a sample of an unmodified conjugated diene polymer or a conjugated diene polymer coupled with a nitrogen atom-containing modifier (hereinafter also referred to as "conjugated diene polymer").
The measurement temperature was 110℃in the case of using an unmodified conjugated diene polymer as a sample, and 100℃in the case of using a conjugated diene polymer as a sample.
The test specimen was first preheated at the test temperature for 1 minute, after which the rotor was rotated at 2rpm,the torque after 4 minutes was measured and used as the Mooney viscosity (ML (1+4) )。
(physical Property 2) Mooney stress relaxation Rate
The conjugated diene polymer was used as a sample, the Mooney viscosity was measured using an L-shaped rotor according to ISO 289, the rotation of the rotor was stopped immediately after the Mooney viscosity was measured using a Mooney viscometer (trade name "VR1132" manufactured by Shimadzu corporation), the torque was recorded at intervals of 0.1 seconds during the period of 1.6 seconds to 5 seconds after the stop in Mooney units, the torque was plotted as a double logarithm with respect to time (seconds), and the slope of the straight line at that time was obtained, and the absolute value was used as the Mooney stress relaxation rate (MSR).
(physical Property 3) degree of branching (Bn)
The branching degree (Bn) of the conjugated diene polymer was measured by GPC-light scattering measurement with a viscosity detector as follows.
The conjugated diene polymer was used as a sample, and measured using a Gel Permeation Chromatography (GPC) measuring apparatus (trade name "GPCmax VE-2001" manufactured by Malvern corporation) in which 3 columns each having a polystyrene gel as a filler were connected, using 3 detectors each having a light scattering detector, an RI detector, and a viscosity detector (trade name "TDA305" manufactured by Malvern corporation) connected in this order, and the absolute molecular weight was determined from the results of the light scattering detector and the RI detector, and the intrinsic viscosity was determined from the results of the RI detector and the viscosity detector, based on standard polystyrene.
Use of linear polymers as basis for intrinsic viscosity [ eta ]]=-3.883M 0.771 The shrinkage factor (g') was calculated as an intrinsic viscosity ratio corresponding to each molecular weight. In the formula, M represents an absolute molecular weight.
Thereafter, the branching degree (Bn) defined as g '=6bn/{ (bn+1) (bn+2) } is calculated using the resulting shrinkage factor (g').
The eluent used was tetrahydrofuran (hereinafter also referred to as "THF") containing 5mmol/L of triethylamine.
For the column, trade names "TSKgel G4000HXL", "TSKgel G5000HXL" manufactured by Tosoh corporation and "TSKgel G6000HXL" were used in connection.
20mg of a sample for measurement was dissolved in 10mL of THF to prepare a measurement solution, and 100. Mu.L of the measurement solution was poured into a GPC measurement apparatus, and measurement was performed at an oven temperature of 40℃and a THF flow rate of 1 mL/min.
(physical Property 4) molecular weight
< measurement condition 1>:
the weight average molecular weight (Mw), the number average molecular weight (Mn) and the molecular weight distribution (Mw/Mn) were determined based on a calibration curve obtained using standard polystyrene by measuring a chromatogram using an RI detector (trade name "HLC8020" manufactured by Tosoh corporation) using 3 GPC measuring devices (trade name "HLC-8320GPC" manufactured by Tosoh corporation) to which 3 polystyrene-based gels as fillers were connected, using an unmodified conjugated diene polymer or a conjugated diene polymer as a sample.
The eluent was THF (tetrahydrofuran) containing 5mmol/L of triethylamine. The column was used with 3 pieces of trade name "TSKgel SuperMultiporeHZ-H" manufactured by Tosoh corporation, and the trade name "TSK guard column SuperMP (HZ) -H" manufactured by Tosoh corporation as a guard column was connected to the front end of the column.
10mg of the measurement sample was dissolved in 10mL of THF to prepare a measurement solution, and 10. Mu.L of the measurement solution was poured into a GPC measurement apparatus, and measurement was performed under conditions of an oven temperature of 40℃and a THF flow rate of 0.35 mL/min.
Among the various samples to be measured under the above measurement condition 1, the samples having a molecular weight distribution (Mw/Mn) of less than 1.6 were reused under the following measurement condition 2. The sample having a molecular weight distribution value of 1.6 or more was measured under the measurement condition 1, and the measurement was performed under the measurement condition 1.
< measurement condition 2>:
the weight average molecular weight (Mw) and the number average molecular weight (Mn) were determined based on calibration curves obtained using standard polystyrene by measuring chromatograms using GPC measurement apparatuses in which 3 columns each containing a polystyrene gel as a filler were connected to an unmodified conjugated diene polymer or a conjugated diene polymer as a sample.
The eluent was THF containing 5mmol/L triethylamine. As regards the column, a protection column is used: trade name "TSK guard column SuperH-H", column manufactured by Tosoh Corp: trade names "TSKgel SuperH5000", "TSKgel SuperH6000", "TSKgel SuperH7000" manufactured by Tosoh corporation.
An RI detector (trade name "HLC8020" manufactured by Tosoh corporation) was used at an oven temperature of 40℃and a THF flow rate of 0.6 mL/min. 10mg of the measurement sample was dissolved in 20mL of THF to prepare a measurement solution, and 20. Mu.L of the measurement solution was poured into a GPC measurement apparatus to measure.
For the sample having a molecular weight distribution value of less than 1.6 measured under the measurement condition 1, the measurement was performed under the measurement condition 2.
(physical Property 5) modification ratio
The modification rate of the conjugated diene polymer was measured by the column adsorption GPC method as follows.
The measurement was performed by using the modified basic polymer component as a sample and by using the characteristic that the modified basic polymer component was adsorbed on a GPC column using silica gel as a filler.
The modification ratio was obtained by measuring the adsorption amount on a silica column from the difference between a chromatogram obtained by measuring a sample solution containing a sample and a low molecular weight internal standard polystyrene using a polystyrene column and a chromatogram obtained by measuring a silica column.
The details are as follows.
The sample having a molecular weight distribution value of 1.6 or more was measured under the measurement condition 1 described above (physical property 4), and was measured under the following measurement condition 3. The sample having a molecular weight distribution value of less than 1.6 was measured under the above-mentioned measurement condition 1 (physical property 4), and was measured under the following measurement condition 4.
< preparation of sample solution >:
a sample solution was prepared by dissolving 10mg of the sample and 5mg of standard polystyrene in 20mL of THF.
< measurement condition 3>:
GPC measurement conditions using polystyrene column:
using the trade name "HLC-8320GPC" manufactured by Tosoh corporation, THF containing 5mmol/L of triethylamine was used as an eluent, 10. Mu.L of the sample solution was injected into the apparatus, and a chromatogram was obtained using an RI detector under conditions of a column oven temperature of 40℃and a THF flow rate of 0.35 mL/min.
The column was used with 3 pieces of "TSKgel SuperMultiporeHZ-H" manufactured by Tosoh corporation and "TSK guard column SuperMP (HZ) -H" manufactured by Tosoh corporation as a guard column connected to the front end of the column.
< measurement condition 4>:
using THF containing 5mmol/L of triethylamine as an eluent, 20. Mu.L of a sample solution was injected into the apparatus for measurement.
As regards the column, a protection column is used: trade name "TSK guard column SuperH-H", column manufactured by Tosoh Corp: trade names "TSKgel SuperH5000", "TSKgel SuperH6000", "TSKgel SuperH7000" manufactured by Tosoh corporation. Measurement was performed using an RI detector (HLC 8020 manufactured by Tosoh corporation) at a temperature of 40℃in a chromatographic column incubator and a THF flow rate of 0.6 mL/min, to obtain a chromatogram.
GPC measurement conditions using silica-based column:
using the trade name "HLC-8320GPC", manufactured by Tosoh corporation, THF was used as an eluent, 50. Mu.L of the sample solution was injected into the apparatus, and a chromatogram was obtained using an RI detector under conditions of a column oven temperature of 40℃and a THF flow rate of 0.5 mL/min. As the column, trade names "Zorbax PSA-1000S", "PSA-300S" and "PSA-60S" were used in connection, and trade names "DIOL 4.6X12.5 mm 5 mcron" as a guard column was used in connection with the front end thereof.
The modification rate calculation method comprises the following steps:
the modification ratio (%) was obtained by assuming that the entire peak area of the chromatogram using the polystyrene column was 100, the peak area of the sample was P1, the peak area of the standard polystyrene was P2, the entire peak area of the chromatogram using the silica column was 100, the peak area of the sample was P3, and the peak area of the standard polystyrene was P4.
Modification ratio (%) = [1- (p2×p3)/(p1×p4) ]×100
(wherein p1+p2=p3+p4=100)
(physical Property 6) amount of bound styrene
A measurement sample was prepared by dissolving 100mg of a conjugated diene polymer coupled without a rubber softener in 100mL of chloroform.
The amount of bound styrene (mass%) was measured as 100 mass% relative to the conjugated diene polymer as a sample by the amount of the phenyl group absorbed by the ultraviolet absorption wavelength (around 254 nm) (measuring device: spectrophotometer "UV-2450" manufactured by Shimadzu corporation).
(Property 7) microstructure of butadiene portion (1, 2-vinyl bond content)
A conjugated diene polymer coupled without a rubber softener was used as a sample, and 50mg of the sample was dissolved in 10mL of carbon disulfide to prepare a measurement sample.
Using a solution dish at 600-1000 cm -1 The microstructure of the butadiene portion, i.e., the 1, 2-vinyl bond amount (mol%) was determined from the absorbance at a predetermined wavenumber according to the calculation method of Hampton method (R.R. Hampton, analytical Chemistry, 923 (1949)), which was a measurement device, a Fourier transform infrared spectrometer "FT-IR230" manufactured by Japanese spectroscopic Co., ltd.
(Property 8) molecular weight (absolute molecular weight Mw-i) measured by GPC-light scattering method
The weight average molecular weight (Mw-i) (also referred to as "absolute molecular weight") was determined based on the solution viscosity and the light scattering method by measuring a chromatogram using a GPC-light scattering measuring apparatus in which 3 columns each of which uses a polystyrene gel as a filler were connected to a conjugated diene polymer as a sample.
The eluent was prepared using a mixed solution of tetrahydrofuran and triethylamine (THF in TEA: 5mL of triethylamine in 1L of tetrahydrofuran).
With respect to the column, the column will be protected: trade name "TSK guard column HHR-H" manufactured by Tosoh corporation and column: trade names "TSKgel G6000HHR", "TSKgel G5000HHR", "TSKgel G4000HHR" manufactured by Tosoh corporation are used in connection.
GPC-light scattering measurement apparatus (trade name "Viscotek TDAmax" manufactured by Malvern Co., ltd.) was used at oven temperature of 40℃and THF flow rate of 1.0 mL/min.
10mg of a sample for measurement was dissolved in 20mL of THF to prepare a measurement solution, and 200. Mu.L of the measurement solution was poured into a GPC measurement apparatus to measure.
(evaluation 9) change with time (Mooney viscosity after 1 month increases)
The conjugated diene polymer was stored at normal temperature and normal pressure for 1 month, and the Mooney viscosity after storage was measured to calculate the difference from the Mooney viscosity measured immediately after polymerization.
The table is expressed as "δml mooney viscosity".
The smaller the value, the less the change with time, and the more excellent the quality stability.
[ branched conjugated diene Polymer ]
Example 2-1 branched conjugated diene Polymer (sample 2-1)
A tank-type pressure vessel having a stirrer and a jacket for controlling temperature, which was a tank-type reactor having an internal volume of 10L, a ratio (L/D) of the height (L) to the diameter (D) of 4.0, an inlet at the bottom and an outlet at the top, was used as a polymerization reactor, and 2 stages thereof were connected.
1, 3-butadiene from which water had been removed in advance was mixed at 18.6 g/min, styrene at 10.0 g/min, and n-hexane at 175.2 g/min. N-butyllithium for inert treatment of mixed residual impurities was added at 0.103 mmol/min to a static mixer provided in the middle of a pipe for supplying the mixed solution to the inlet of the reactor, and then continuously supplied to the bottom of the reactor. Further, 2-bis (2-tetrahydrofuranyl) propane as a polar substance was fed at a rate of 0.081 mmol/min and n-butyllithium as a polymerization initiator was fed at a rate of 0.143 mmol/min to the bottom of the 1 st reactor vigorously mixed with a stirrer, and the internal temperature of the reactor was maintained at 67 ℃.
The polymer solution was continuously withdrawn from the top of the 1 st reactor, continuously fed to the bottom of the 2 nd reactor, continuously reacted at 70℃and further fed from the top of the 2 nd reactor to the static mixer. At the time of sufficiently stabilizing the polymerization, 1, 3-butadiene and styrene were copolymerized, and trimethoxy (4-vinylphenyl) silane (abbreviated as "BS-1" in the table) was added as a branching agent from the bottom of the 2 nd reactor at a rate of 0.0190 mmol/min to carry out the polymerization reaction and the branching reaction, thereby obtaining a conjugated diene polymer having a main chain branched structure.
Further, at the time of stabilizing the polymerization reaction and branching reaction, the conjugated diene polymer solution before the addition of the modifier was withdrawn in a small amount, an antioxidant (BHT) was added so as to be 0.2g per 100g of the polymer, and then the solvent was removed, and the Mooney viscosity at 110℃and various molecular weights were measured. The physical properties are shown in Table 13.
Then, to the polymer solution flowing out of the outlet of the reactor, a compound A-1 (a compound represented by (A-1) out of the above < compounds [ A ] >, used in the modification step) was continuously added at a rate of 0.0360 mmol/min, and the mixture was mixed using a static mixer to carry out the coupling reaction. At this time, the time until the addition of the modifier to the polymer solution flowing out of the outlet of the reactor was 4.8 minutes, the temperature was 68℃and the difference between the temperature in the polymerization step and the temperature before the addition of the modifier was 2 ℃.
The conjugated diene polymer solution after the coupling reaction was extracted in a small amount, and an antioxidant (BHT) was added so as to be 0.2g per 100g of the polymer, followed by removal of the solvent, whereby the amount of bound styrene (physical property 6) and the microstructure of the butadiene portion (1, 2-vinyl binding amount: physical property 7) were measured. The measurement results are shown in Table 13.
Subsequently, an antioxidant (BHT) was continuously added to the polymer solution after the coupling reaction at 0.055 g/min (n-hexane solution) per 100g of the polymer to terminate the coupling reaction. Simultaneously with the antioxidant, SRAE oil (JOMO Process NC140 manufactured by JX daily ore energy company) was continuously added as a rubber softener in an amount of 25.0g relative to 100g of the polymer, and the mixture was mixed by a static mixer. The solvent was removed by stripping to obtain a branched conjugated diene polymer (sample 2-1).
The physical properties of sample 2-1 are shown in Table 13.
The structure of the branched conjugated diene polymer was determined by comparing the molecular weight measured by GPC with the branching degree measured by GPC with a viscometer for the polymer before addition of the branching agent, the polymer after addition of the branching agent, and the polymer in each step after addition of the coupling agent. The structure of each sample was identified in the same manner as follows.
Example 2-2 branched conjugated diene Polymer (sample 2-2)
A branched conjugated diene polymer (sample 2-2) was obtained in the same manner as in example 2-1 except that the coupling agent was changed from the compound A-1 to the compound A-2 (the compound represented by (A-2) in the above < compound [ A ] > used in the modification step.
The physical properties of sample 2-2 are shown in Table 13.
Examples 2 to 3 branched conjugated diene polymers (samples 2 to 3)
A branched conjugated diene polymer (sample 2-3) was obtained in the same manner as in example 2-1 except that the coupling agent was changed from the compound A-1 to the compound A-4 (the compound represented by (A-4) in the above < compound [ A ] > used in the modification step; abbreviated as "A-4" in the table) and the amount added was 0.0720 mmol/min.
The physical properties of sample 2-3 are shown in Table 13.
Examples 2 to 4 branched conjugated diene polymers (samples 2 to 4)
A branched conjugated diene polymer (sample 2-4) was obtained in the same manner as in example 2-1 except that the coupling agent was changed from the compound A-1 to the compound A-6 (the compound represented by (A-6) in the above < compound [ A ] > used in the modification step.
Physical properties of samples 2 to 4 are shown in Table 13.
Examples 2 to 5 branched conjugated diene polymers (samples 2 to 5)
A branched conjugated diene polymer (sample 2-5) was obtained in the same manner as in example 2-1 except that the coupling agent was changed from the compound A-1 to the compound A-8 (the compound represented by (A-8) in the above < compound [ A ] > used in the modification step; abbreviated as "A-8" in the table) and the amount added was 0.0720 mmol/min.
The physical properties of samples 2 to 5 are shown in Table 13.
Examples 2 to 6 branched conjugated diene polymers (samples 2 to 6)
A branched conjugated diene polymer (sample 2-6) was obtained in the same manner as in example 2-1 except that the coupling agent was changed from the compound A-1 to the compound A-9 (the compound represented by (A-9) in the above < compound [ A ] > used in the modification step.
Physical properties of samples 2 to 6 are shown in Table 13.
Examples 2 to 7 branched conjugated diene polymers (samples 2 to 7)
A branched conjugated diene polymer (sample 2-7) was obtained in the same manner as in example 2-1 except that the coupling agent was changed from the compound A-1 to the compound A-10 (the compound represented by (A-10) in the above < compound [ A ] > used in the modification step.
Physical properties of samples 2 to 7 are shown in Table 13.
Examples 2 to 8 branched conjugated diene polymers (samples 2 to 8)
A branched conjugated diene polymer (sample 2-8) was obtained in the same manner as in example 2-1 except that the coupling agent was changed from the compound A-1 to the compound A-12 (the compound represented by (A-12) in the above < compound [ A ] > used in the modification step; abbreviated as "A-12" in the table) and the amount added was 0.0720 mmol/min.
Physical properties of samples 2 to 8 are shown in Table 13.
Examples 2 to 9 branched conjugated diene polymers (samples 2 to 9)
A branched conjugated diene polymer (sample 2-9) was obtained in the same manner as in example 2-1 except that the coupling agent was changed from the compound A-1 to the compound A-13 (the compound represented by (A-13) in the above < compound [ A ] > used in the modification step; the amount added was abbreviated as "A-13" in the table) and 0.0160 mmol/min.
Physical properties of samples 2 to 9 are shown in Table 13.
Examples 2 to 10 branched conjugated diene polymers (samples 2 to 10)
A branched conjugated diene polymer (sample 2-10) was obtained in the same manner as in example 2-1 except that the coupling agent was changed from the compound A-1 to the compound A-14 (the compound represented by (A-14) in the above < compound [ A ] > used in the modification step; the amount added is abbreviated as "A-14" in the table) and 0.0160 mmol/min.
Physical properties of samples 2 to 10 are shown in Table 13.
Examples 2 to 11 branched conjugated diene polymers (samples 2 to 11)
A branched conjugated diene polymer (sample 2-11) was obtained in the same manner as in example 2-1 except that the coupling agent was changed from the compound A-1 to the compound A-15 (the compound represented by (A-15) in the above < compound [ A ] > used in the modification step; abbreviated as "A-15" in the table) and the amount added was 0.0360 mmol/min.
Physical properties of samples 2 to 11 are shown in Table 13.
Examples 2 to 12 branched conjugated diene polymers (samples 2 to 12)
A branched conjugated diene polymer (sample 2-12) was obtained in the same manner as in example 2-1, except that the branching agent was changed from trimethoxy (4-vinylphenyl) silane to dimethylmethoxy (4-vinylphenyl) silane (abbreviated as "BS-2" in the table) and the amount added was 0.0350 mmol/min.
Physical properties of samples 2 to 12 are shown in Table 14.
Examples 2 to 13 branched conjugated diene polymers (samples 2 to 13)
A branched conjugated diene polymer (sample 2-13) was obtained in the same manner as in example 2-1, except that the branching agent was changed from trimethoxy (4-vinylphenyl) silane to dimethylmethoxy (4-vinylphenyl) silane (abbreviated as "BS-2" in the table), the amount of the branching agent added was changed to 0.0350 mmol/min, and the coupling agent was changed from compound A-1 to compound A-2 (compound shown as (A-2) in the above < compound [ A ] > used in the modification step).
The physical properties of samples 2 to 13 are shown in Table 14.
Examples 2 to 14 branched conjugated diene polymers (samples 2 to 14)
A branched conjugated diene polymer (sample 2-14) was obtained in the same manner as in example 2-1, except that the branching agent was changed from trimethoxy (4-vinylphenyl) silane to dimethylmethoxy (4-vinylphenyl) silane (abbreviated as "BS-2" in the table) and the amount of the branching agent added was changed from compound A-1 to compound A-14 (compound shown as (A-14) in the above < compound [ A ] > used in the modification step), and the amount of the branching agent added was changed to 0.0160 mmol/min.
Physical properties of samples 2 to 14 are shown in Table 14.
Examples 2 to 15 branched conjugated diene polymers (samples 2 to 15)
A branched conjugated diene polymer (samples 2-15) was obtained in the same manner as in example 2-1, except that the branching agent was changed from trimethoxy (4-vinylphenyl) silane to 1, 1-bis (4- (dimethylmethoxysilyl) phenyl) ethylene (abbreviated as "BS-3" in the table) and the amount added was 0.0120 mmol/min.
Physical properties of samples 2 to 15 are shown in Table 14.
Examples 2 to 16 branched conjugated diene polymers (samples 2 to 16)
A branched conjugated diene polymer (sample 2-16) was obtained in the same manner as in example 2-1, except that the branching agent was changed from trimethoxy (4-vinylphenyl) silane to 1, 1-bis (4- (dimethylmethoxysilyl) phenyl) ethylene (abbreviated as "BS-3" in the table), the amount of the branching agent added was changed to 0.0120 mmol/min, the coupling agent was changed from compound A-1 (abbreviated as "A-1" in the table) to compound A-2 (the compound shown as (A-2) in the above-mentioned < compound [ A ] > < used in the modification step >; abbreviated as "A-2" in the table), and the amount of the branching agent added was changed to 0.0360 mmol/min.
Physical properties of samples 2 to 16 are shown in Table 14.
Examples 2 to 17 branched conjugated diene polymers (samples 2 to 17)
A branched conjugated diene polymer (sample 2-17) was obtained in the same manner as in example 2-1 except that the branching agent was changed from trimethoxy (4-vinylphenyl) silane to 1, 1-bis (4- (dimethylmethoxysilyl) phenyl) ethylene (abbreviated as "BS-3" in the table), the amount of the branching agent added was changed to 0.0120 mmol/min, the coupling agent was changed from compound A-1 (abbreviated as "A-1" in the table) to compound A-14 (indicated as (A-14) in the above-mentioned < compound [ A ] > (abbreviated as "A-14" in the table) used in the modification step), and the amount of the branching agent added was changed to 0.0160 mmol/min.
Physical properties of samples 2 to 17 are shown in Table 14.
Examples 2 to 18 branched conjugated diene polymers (samples 2 to 18)
A branched conjugated diene polymer (samples 2-18) was obtained in the same manner as in example 2-1, except that the branching agent was changed from trimethoxy (4-vinylphenyl) silane to 1, 1-bis (4-trimethoxysilylphenyl) ethylene (abbreviated as "BS-4" in the table) and the amount added was changed to 0.0210 mmol/min.
Physical properties of samples 2 to 18 are shown in Table 14.
Examples 2 to 19 branched conjugated diene polymers (samples 2 to 19)
A branched conjugated diene polymer (sample 2-19) was obtained in the same manner as in example 2-1, except that the branching agent was changed from trimethoxy (4-vinylphenyl) silane to 1, 1-bis (4-trimethoxysilylphenyl) ethylene (abbreviated as "BS-4" in the table) and the amount added was changed to 0.0210 mmol/min, and the coupling agent was changed from compound A-1 (abbreviated as "A-1" in the table) to compound A-2 (the compound shown by (A-2) in the above < compound [ A ] > used in the modification step.
Physical properties of samples 2 to 19 are shown in Table 14.
Examples 2 to 20 branched conjugated diene polymers (samples 2 to 20)
A branched conjugated diene polymer (sample 2-20) was obtained in the same manner as in example 2-1, except that the branching agent was changed from trimethoxy (4-vinylphenyl) silane to 1, 1-bis (4-trimethoxysilylphenyl) ethylene (abbreviated as "BS-4" in the table) and the coupling agent was changed from compound A-1 (abbreviated as "A-1" in the table) to compound A-14 (compound shown as (A-14) in the above-mentioned < compound [ A ] > < used in the modifying step >; abbreviated as "A-14" in the table) and the amount added was changed to 0.0160 mmol/min.
Physical properties of samples 2 to 20 are shown in Table 14.
Examples 2 to 21 branched conjugated diene polymers (samples 2 to 21)
A branched conjugated diene polymer (sample 2-21) was obtained in the same manner as in example 2-1, except that the branching agent was changed from trimethoxy (4-vinylphenyl) silane to trichloro (4-vinylphenyl) silane (abbreviated as "BS-5" in the table) and the amount added was 0.0190 mmol/min.
Physical properties of samples 2 to 21 are shown in Table 14.
Examples 2 to 22 branched conjugated diene polymers (samples 2 to 22)
A branched conjugated diene polymer (sample 2-22) was obtained in the same manner as in example 2-1, except that the branching agent was changed from trimethoxy (4-vinylphenyl) silane to trichloro (4-vinylphenyl) silane (abbreviated as "BS-5" in the table), the amount of the branching agent added was changed to 0.0190 mmol/min, the coupling agent was changed from compound A-1 (abbreviated as "A-1" in the table) to compound A-2 (indicated as (A-2) in the above < compound [ A ] >) used in the modification step, the amount of the branching agent added was changed to 0.0360 mmol/min.
Physical properties of samples 2 to 22 are shown in Table 14.
Examples 2 to 23 branched conjugated diene polymers (samples 2 to 23)
A branched conjugated diene polymer (sample 2-23) was obtained in the same manner as in example 2-1, except that the branching agent was changed from trimethoxy (4-vinylphenyl) silane to trichloro (4-vinylphenyl) silane (abbreviated as "BS-5" in the table), the amount of the branching agent added was changed to 0.0190 mmol/min, the coupling agent was changed from compound A-1 (abbreviated as "A-1" in the table) to compound A-14 (abbreviated as "A-14" in the above-mentioned < compound [ A ] >) used in the modification step, and the amount of the branching agent added was changed to 0.0160 mmol/min.
Physical properties of samples 2 to 23 are shown in Table 14.
Example A-1 branched conjugated diene Polymer (sample A-1)
A tank-type pressure vessel having a stirrer and a jacket for controlling temperature, which was a tank-type reactor having an internal volume of 10L, a ratio (L/D) of the height (L) to the diameter (D) of 4.0, an inlet at the bottom and an outlet at the top, was used as a polymerization reactor, and 2 stages thereof were connected.
1, 3-butadiene from which water had been removed in advance was mixed at 14.0 g/min, styrene at 10.0 g/min, and n-hexane at 175.2 g/min. N-butyllithium for inert treatment of mixed residual impurities was added at 0.103 mmol/min to a static mixer provided in the middle of a pipe for supplying the mixed solution to the inlet of the reactor, and then continuously supplied to the bottom of the reactor. Further, 2-bis (2-tetrahydrofuranyl) propane as a polar substance was fed at a rate of 0.081 mmol/min and n-butyllithium as a polymerization initiator was fed at a rate of 0.143 mmol/min to the bottom of the 1 st reactor vigorously mixed with a stirrer, and the internal temperature of the reactor was maintained at 67 ℃.
The polymer solution was continuously withdrawn from the top of the 1 st reactor, continuously fed to the bottom of the 2 nd reactor, continuously reacted at 70℃and further fed from the top of the 2 nd reactor to the static mixer. At the time of sufficiently stabilizing the polymerization, 1, 3-butadiene and styrene were copolymerized, trimethoxy (4-vinylphenyl) silane (abbreviated as "BS-1" in the table) was added as a branching agent from the bottom of the 2 nd reactor at a rate of 0.0190 mmol/min, and 1, 3-butadiene was added in parallel at a rate of 4.6 g/min, to carry out the polymerization reaction and the branching reaction, thereby obtaining a conjugated diene polymer having a main chain branched structure.
Further, at the time of stabilization of the polymerization reaction and branching reaction, the conjugated diene polymer solution before the addition of the coupling agent was withdrawn in a small amount, an antioxidant (BHT) was added so as to be 0.2g per 100g of the polymer, and then the solvent was removed, and the Mooney viscosity at 110℃and various molecular weights were measured. The physical properties are shown in Table 15.
Then, as a coupling agent, the compound A-1 was changed to a compound A-9 (the compound represented by (A-9) among the compounds [ A ] > used in the above < modification step >. Abbreviated as "A-9" in the table), and the mixture was continuously added to the polymer solution flowing out from the outlet of the reactor in an amount of 0.0360 mmol/min, and mixed by a static mixer to carry out a coupling reaction.
At this time, the time until the addition of the coupling agent to the polymer solution flowing out of the outlet of the reactor was 4.8 minutes, the temperature was 68℃and the difference between the temperature in the polymerization step and the temperature before the addition of the coupling agent was 2 ℃.
The conjugated diene polymer solution after the coupling reaction was extracted in a small amount, and an antioxidant (BHT) was added so as to be 0.2g per 100g of the polymer, followed by removal of the solvent, whereby the amount of bound styrene (physical property 6) and the microstructure of the butadiene portion (1, 2-vinyl binding amount: physical property 7) were measured. The measurement results are shown in Table 15.
Subsequently, an antioxidant (BHT) was continuously added to the polymer solution after the coupling reaction at 0.055 g/min (n-hexane solution) per 100g of the polymer to terminate the coupling reaction.
SRAE oil (JOMO Process NC140 manufactured by JX daily ore energy company) as a softener for rubber was continuously added to the polymer at 25.0g relative to 100g of the antioxidant, and mixed by a static mixer.
The solvent was removed by stripping to obtain a branched conjugated diene polymer having a 4-branched structure derived from a branching agent and a 4-branched star-shaped polymer structure derived from a coupling agent in a part of the main chain (sample A-1).
The physical properties of sample A-1 are shown in Table 15.
The structure of the polymer was identified by comparing the molecular weight measured by GPC with the branching degree measured by GPC with a viscometer, with respect to the polymer before the addition of the branching agent, the polymer after the addition of the branching agent, and the polymer in each step after the addition of the coupling agent.
Example A-2 branched conjugated diene Polymer (sample A-2)
A tank-type pressure vessel having a stirrer and a jacket for controlling temperature, which was a tank-type reactor having an internal volume of 10L, a ratio (L/D) of the height (L) to the diameter (D) of 4.0, an inlet at the bottom and an outlet at the top, was used as a polymerization reactor, and 2 stages thereof were connected.
1, 3-butadiene from which water had been removed in advance was mixed at 14.0 g/min, styrene at 8.0 g/min and n-hexane at 175.2 g/min. N-butyllithium for inert treatment of mixed residual impurities was added at 0.103 mmol/min to a static mixer provided in the middle of a pipe for supplying the mixed solution to the inlet of the reactor, and then continuously supplied to the bottom of the reactor. Further, 2-bis (2-tetrahydrofuranyl) propane as a polar substance was fed at a rate of 0.081 mmol/min and n-butyllithium as a polymerization initiator was fed at a rate of 0.143 mmol/min to the bottom of the 1 st reactor vigorously mixed with a stirrer, and the internal temperature of the reactor was maintained at 67 ℃.
The polymer solution was continuously withdrawn from the top of the 1 st reactor, continuously fed to the bottom of the 2 nd reactor, continuously reacted at 70℃and further fed from the top of the 2 nd reactor to the static mixer. At the time of sufficiently stabilizing the polymerization, 1, 3-butadiene and styrene were copolymerized, trimethoxy (4-vinylphenyl) silane (abbreviated as "BS-1" in the table) was added as a branching agent from the bottom of the 2 nd reactor at a rate of 0.0190 mmol/min, 1, 3-butadiene was added in parallel at 4.6 g/min, and styrene was added at 2.0 g/min, and polymerization reaction and branching reaction were carried out to obtain a conjugated diene polymer having a main chain branched structure.
Further, at the time of stabilization of the polymerization reaction and branching reaction, the conjugated diene polymer solution before the addition of the coupling agent was withdrawn in a small amount, an antioxidant (BHT) was added so as to be 0.2g per 100g of the polymer, and then the solvent was removed, and the Mooney viscosity at 110℃and various molecular weights were measured. The physical properties are shown in Table 15.
Then, as a coupling agent, the compound A-1 was changed to a compound A-9 (the compound represented by (A-9) among the compounds [ A ] > used in the above < modification step >. Abbreviated as "A-9" in the table), and the mixture was continuously added to the polymer solution flowing out from the outlet of the reactor in an amount of 0.0360 mmol/min, and mixed by a static mixer to carry out a coupling reaction.
At this time, the time until the addition of the coupling agent to the polymer solution flowing out of the outlet of the reactor was 4.8 minutes, the temperature was 68℃and the difference between the temperature in the polymerization step and the temperature before the addition of the coupling agent was 2 ℃.
The conjugated diene polymer solution after the coupling reaction was extracted in a small amount, and an antioxidant (BHT) was added so as to be 0.2g per 100g of the polymer, followed by removal of the solvent, whereby the amount of bound styrene (physical property 6) and the microstructure of the butadiene portion (1, 2-vinyl binding amount: physical property 7) were measured. The measurement results are shown in Table 15.
Subsequently, an antioxidant (BHT) was continuously added to the polymer solution after the coupling reaction at 0.055 g/min (n-hexane solution) per 100g of the polymer to terminate the coupling reaction. SRAE oil (JOMO Process NC140 manufactured by JX daily ore energy company) as a softener for rubber was continuously added to the polymer at 25.0g relative to 100g of the antioxidant, and mixed by a static mixer.
The solvent was removed by stripping to obtain a branched conjugated diene polymer having a 4-branched structure derived from the branching agent and having a 4-branched star-shaped polymer structure derived from the coupling agent (sample A-2).
The physical properties of sample A-2 are shown in Table 15.
The structure of the polymer was identified by comparing the molecular weight measured by GPC with the branching degree measured by GPC with a viscometer, with respect to the polymer before the addition of the branching agent, the polymer after the addition of the branching agent, and the polymer in each step after the addition of the coupling agent.
Comparative example 2-1 conjugated diene polymers (samples 2-24)
A tank-type pressure vessel having a stirrer and a jacket for controlling temperature, which was a tank-type reactor having an internal volume of 10L, a ratio (L/D) of the height (L) to the diameter (D) of 4.0, an inlet at the bottom and an outlet at the top, was used as a polymerization reactor, and 2 stages thereof were connected.
1, 3-butadiene from which water had been removed in advance was mixed at 18.6 g/min, styrene at 10.0 g/min, and n-hexane at 175.2 g/min. N-butyllithium for inert treatment of mixed residual impurities was added at 0.103 mmol/min to a static mixer provided in the middle of a pipe for supplying the mixed solution to the inlet of the reactor, and then continuously supplied to the bottom of the reactor. Further, 2-bis (2-tetrahydrofuranyl) propane as a polar substance was fed at a rate of 0.081 mmol/min and n-butyllithium as a polymerization initiator was fed at a rate of 0.143 mmol/min to the bottom of the 1 st reactor vigorously mixed with a stirrer, and the internal temperature of the reactor was maintained at 67 ℃.
The polymer solution was continuously withdrawn from the top of the 1 st reactor, continuously fed to the bottom of the 2 nd reactor, continuously reacted at 70℃and further fed from the top of the 2 nd reactor to the static mixer. At the time of sufficiently stabilizing the polymerization, the polymer solution before the addition of the modifier was withdrawn in a small amount, an antioxidant (BHT) was added so as to be 0.2g per 100g of the polymer, and then the solvent was removed, and the Mooney viscosity at 110℃and various molecular weights were measured. The physical properties are shown in Table 16.
Then, the compound A-1 (the compound represented by (A-1) among the compounds [ A ] > used in the above < modification step, "A-1" in the table) as a coupling agent was continuously added to the polymer solution flowing out of the outlet of the reactor at a rate of 0.0360 mmol/min, and mixed using a static mixer, and a coupling reaction was carried out.
At this time, the time until the addition of the modifier to the polymer solution flowing out of the outlet of the reactor was 4.8 minutes, the temperature was 68℃and the difference between the temperature in the polymerization step and the temperature before the addition of the modifier was 2 ℃.
The conjugated diene polymer solution after the coupling reaction was extracted in a small amount, and an antioxidant (BHT) was added so as to be 0.2g per 100g of the polymer, followed by removal of the solvent, whereby the amount of bound styrene (physical property 6) and the microstructure of the butadiene portion (1, 2-vinyl binding amount: physical property 7) were measured. The measurement results are shown in Table 16.
Subsequently, an antioxidant (BHT) was continuously added to the polymer solution after the coupling reaction at 0.055 g/min (n-hexane solution) per 100g of the polymer to terminate the coupling reaction. SRAE oil (JOMO Process NC140 manufactured by JX daily ore energy company) as a softener for rubber was continuously added simultaneously with an antioxidant so as to be 25.0g relative to 100g of the polymer, and mixed by a static mixer. The solvent was removed by stripping to obtain conjugated diene polymers (samples 2 to 24). Physical properties of samples 2 to 24 are shown in Table 16.
Comparative examples 2-2 conjugated diene polymers (samples 2-25)
A conjugated diene polymer (sample 2-25) was obtained in the same manner as in comparative example 1, except that the coupling agent was changed from the compound A-1 (abbreviated as "A-1" in the table) to the compound A-2 (the compound shown by (A-2) in the above-mentioned < compound [ A ] > used in the modification step).
Physical properties of samples 2 to 25 are shown in Table 16.
Comparative examples 2 to 3 conjugated diene polymers (samples 2 to 26)
A conjugated diene polymer (sample 2-26) was obtained in the same manner as in comparative example 2-1 except that the coupling agent was changed from the compound A-1 (abbreviated as "A-1" in the table) to the compound A-3 (the compound represented by (A-3) in the above-mentioned < compound [ A ] > used in the modification step), and the addition amount thereof was changed to 0.0720 mmol/min.
Physical properties of samples 2 to 26 are shown in Table 16.
Comparative examples 2 to 4 conjugated diene polymers (samples 2 to 27)
A conjugated diene polymer (sample 2-27) was obtained in the same manner as in comparative example 2-1 except that the coupling agent was changed from the compound A-1 to the compound A-6 (the compound represented by (A-6) in the above < compound [ A ] > used in the modification step, which is abbreviated as "A-6" in the table).
Physical properties of samples 2 to 27 are shown in Table 16.
Comparative examples 2 to 5 conjugated diene polymers (samples 2 to 28)
A conjugated diene polymer (sample 2-28) was obtained in the same manner as in comparative example 2-1 except that the coupling agent was changed from the compound A-1 to the compound A-8 (the compound represented by (A-8) in the above < compound [ A ] > used in the modification step, which is abbreviated as "A-8" in the table), and the amount of the coupling agent added was 0.0720 mmol/min.
Physical properties of samples 2 to 28 are shown in Table 16.
Comparative examples 2 to 6 conjugated diene polymers (samples 2 to 29)
A conjugated diene polymer (sample 2-29) was obtained in the same manner as in comparative example 2-1 except that the coupling agent was changed from the compound A-1 to the compound A-9 (the compound represented by (A-9) in the above < compound [ A ] > used in the modification step, which is abbreviated as "A-9" in the table).
Physical properties of samples 2 to 29 are shown in Table 16.
Comparative examples 2 to 7 conjugated diene polymers (samples 2 to 30)
A conjugated diene polymer (sample 2-30) was obtained in the same manner as in comparative example 2-1 except that the coupling agent was changed from the compound A-1 to the compound A-10 (the compound represented by (A-10) in the above < compound [ A ] > used in the modification step, which is abbreviated as "A-10" in the table).
Physical properties of samples 2 to 30 are shown in Table 16.
Comparative examples 2 to 8 conjugated diene polymers (samples 2 to 31)
A conjugated diene polymer (sample 2-31) was obtained in the same manner as in comparative example 2-1 except that the coupling agent was changed from the compound A-1 to the compound A-12 (the compound represented by (A-12) in the above < compound [ A ] > used in the modification step, which is abbreviated as "A-12" in the table), and the amount of the coupling agent added was 0.0720 mmol/min.
Physical properties of samples 2 to 31 are shown in Table 16.
Comparative examples 2 to 9 conjugated diene polymers (samples 2 to 32)
A conjugated diene polymer (sample 2-32) was obtained in the same manner as in comparative example 2-1 except that the coupling agent was changed from the compound A-1 to the compound A-13 (the compound represented by (A-13) in the above < compound [ A ] > used in the modification step, which was abbreviated as "A-13" in the table), and the amount added was changed to 0.0160 mmol/min.
Physical properties of samples 2 to 32 are shown in Table 16.
Comparative examples 2 to 10 conjugated diene polymers (samples 2 to 33)
A conjugated diene polymer (sample 2-33) was obtained in the same manner as in comparative example 2-1 except that the coupling agent was changed from the compound A-1 to the compound A-14 (the compound represented by (A-14) in the above < compound [ A ] > used in the modification step, which was abbreviated as "A-14" in the table), and the amount added was changed to 0.0160 mmol/min.
The physical properties of sample 33 are shown in Table 16.
Comparative examples 2 to 11 conjugated diene polymers (samples 2 to 34)
A conjugated diene polymer (sample 2-34) was obtained in the same manner as in comparative example 2-1 except that the coupling agent was changed from the compound A-1 to the compound A-15 (the compound represented by (A-15) in the above < compound [ A ] > used in the modification step, which was abbreviated as "A-15" in the table), and the amount of the coupling agent added was 0.0360 mmol/min.
Physical properties of samples 2 to 34 are shown in Table 16.
Comparative example B-1 conjugated diene Polymer (sample B-1)
A tank-type pressure vessel having a stirrer and a jacket for controlling temperature, which was a tank-type reactor having an internal volume of 10L, a ratio (L/D) of the height (L) to the diameter (D) of 4.0, an inlet at the bottom and an outlet at the top, was used as a polymerization reactor, and 2 stages thereof were connected.
1, 3-butadiene from which water had been removed in advance was mixed at 18.6 g/min, styrene at 10.0 g/min, and n-hexane at 175.2 g/min. N-butyllithium for inert treatment of mixed residual impurities was added at 0.103 mmol/min to a static mixer provided in the middle of a pipe for supplying the mixed solution to the inlet of the reactor, and then continuously supplied to the bottom of the reactor. Further, 2-bis (2-tetrahydrofuranyl) propane as a polar substance was fed at a rate of 0.081 mmol/min and n-butyllithium as a polymerization initiator was fed at a rate of 0.143 mmol/min to the bottom of the 1 st reactor vigorously mixed with a stirrer, and the internal temperature of the reactor was maintained at 67 ℃.
The polymer solution was continuously withdrawn from the top of the 1 st reactor, continuously fed to the bottom of the 2 nd reactor, continuously reacted at 70℃and further fed from the top of the 2 nd reactor to the static mixer.
Further, at the time of stabilization of the polymerization reaction, the conjugated diene polymer solution before the addition of the coupling agent was withdrawn in a small amount, an antioxidant (BHT) was added so as to be 0.2g per 100g of the polymer, and then the solvent was removed, and the Mooney viscosity at 110℃and various molecular weights were measured. The physical properties are shown in Table 15.
Next, trimethoxy (4-vinylphenyl) silane (abbreviated as "BS-1" in the table) was added to the polymer solution flowing out from the outlet of the reactor at a rate of 0.0190 mmol/min, while tetraethoxysilane (abbreviated as "A" in the table) was continuously added at a rate of 0.0480 mmol/min, and mixed using a static mixer to carry out a coupling reaction.
In Table 15, "BS-1" of comparative example B-1 is shown in the column of "branching agent", but since "BS-1" is added simultaneously with "A", it fails to form a main chain branched structure and does not function as a branching agent.
At this time, the time until the addition of the coupling agent to the polymer solution flowing out of the outlet of the reactor was 4.8 minutes, the temperature was 68℃and the difference between the temperature in the polymerization step and the temperature before the addition of the coupling agent was 2 ℃.
The conjugated diene polymer solution after the coupling reaction was extracted in a small amount, and an antioxidant (BHT) was added so as to be 0.2g per 100g of the polymer, followed by removal of the solvent, whereby the amount of bound styrene (physical property 6) and the microstructure of the butadiene portion (1, 2-vinyl binding amount: physical property 7) were measured. The measurement results are shown in Table 15.
Subsequently, an antioxidant (BHT) was continuously added to the polymer solution after the coupling reaction at 0.055 g/min (n-hexane solution) per 100g of the polymer to terminate the coupling reaction.
SRAE oil (JOMO Process NC140 manufactured by JX daily ore energy company) as a softener for rubber was continuously added simultaneously with an antioxidant so as to be 25.0g relative to 100g of the polymer, and mixed by a static mixer. The solvent was removed by stripping to obtain a conjugated diene polymer (sample B-1).
The physical properties of sample B-1 are shown in Table 15.
The structure of the polymer was identified by comparing the molecular weight measured by GPC with the branching degree measured by GPC with a viscometer, with respect to the polymer before the addition of the branching agent, the polymer after the addition of the branching agent, and the polymer in each step after the addition of the coupling agent.
Comparative example B-2 conjugated diene Polymer (sample B-2)
As the coupling agent, a coupling agent shown in the following (Z-1) (abbreviated as "Z-1" in the table) was used so that the amount thereof to be added was 0.0360 mmol/min. Other conditions were the same as in comparative example 2-1, to obtain a conjugated diene polymer having a 10-branched star-shaped polymer structure derived from a coupling agent without having a main chain branch derived from a branching agent (sample B-2).
The physical properties of sample B-2 are shown in Table 15.
[ chemical 43]
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(examples 2-24 to 2-46, examples a-1 to 2, comparative examples 2-12 to 2-22, comparative examples b-1 to 2)
[ rubber composition ]
The rubber compositions containing the raw materials rubbers were obtained in the proportions shown below using the samples 2-1 to 2-34, samples A-1 to 2, and samples B-1 to 2 shown in tables 13 to 16 as the raw materials.
(rubber component)
Branched conjugated diene polymer, conjugated diene polymer (samples 2-1 to 2-34, samples A-1 to 2, and samples B-1 to 2): 80 parts by mass (parts by mass of softener for removing rubber)
High cis polybutadiene (trade name "ube pol BR150" manufactured by yu division): 20 parts by mass (mixing condition)
The amount of each compound to be added is expressed in terms of parts by mass relative to 100 parts by mass of the rubber component containing no rubber softener.
Silica 1 (trade name "Ultrasil 7000GR" nitrogen adsorption specific surface area 170m manufactured by Evonik Degussa Co., ltd.) 2 /g): 50.0 parts by mass
Silicon oxide 2 (trade name "Zeosil Premium 200MP" manufactured by Rhodia Co., ltd.) nitrogen adsorption specific surface area 220m 2 /g): 25.0 parts by mass
Carbon black (trade name "sea KH (N339)", manufactured by eastern sea carbon company): 5.0 parts by mass
Silane modifier (trade name "Si75", bis (triethoxysilylpropyl) disulfide manufactured by Evonik Degussa corporation): 6.0 parts by mass
SRAE oil (trade name "Process NC140" manufactured by JX daily ore energy company): 42.0 parts by mass (including the amount added in advance as the softener for rubber contained in samples 2-1 to 2-34, samples A-1 to 2, and samples B-1 to 2)
Zinc white: 2.5 parts by mass
Stearic acid: 1.0 part by mass
Age resistor (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-benzooxazolylsulfenamide): 1.7 parts by mass
Vulcanization accelerator 2 (diphenylguanidine): 2.0 parts by mass
Summation of: 239.4 parts by mass
(kneading method)
The above materials were kneaded by the following method to obtain a rubber composition. The raw rubber (samples 2-1 to 2-34, samples A-1 to 2, and samples B-1 to 2), the filler (silica 1, silica 2, and carbon black), the silane modifier, the SRAE oil, the zinc white, and the stearic acid were kneaded under conditions of a filling rate of 65% and a rotor rotation speed of 30 to 50rpm using a closed kneader (content 0.3L) equipped with a temperature controller. At this time, the temperature of the closed mixer was controlled, and each rubber composition (compound) was obtained under the condition that the discharge temperature was 155 to 160 ℃.
Next, as the second-stage kneading, the compound obtained above was cooled to room temperature, and then an anti-aging agent was added thereto, and kneading was performed again to improve the dispersion of the silica. In this case, the discharge temperature of the compound was also adjusted to 155 to 160 ℃ by temperature control of the mixer.
After cooling, sulfur and vulcanization accelerators 1 and 2 were added to an open mill set at 70℃as the third stage of kneading, and kneaded.
Thereafter, molding was performed, and vulcanization was performed at 160℃for 20 minutes using a vulcanization press.
The rubber composition before vulcanization and the rubber composition after vulcanization were evaluated. Specifically, the evaluation was performed by the following method.
The results are shown in tables 17 to 20.
[ evaluation of Properties ]
(evaluation 1) Mooney viscosity of compound
The compound obtained in the above was used as a sample after the second stage kneading and before the third stage kneading, and after preheating at 130℃for 1 minute according to ISO 289, the rotor was rotated for 4 minutes at 2 revolutions per minute, and the viscosity was measured. The results of comparative examples 2 to 12 were normalized to 100. The smaller the index, the better the processability.
(evaluation 2) tensile Strength and elongation at break
The tensile strength and elongation at break were measured according to the tensile test method of JIS K6251, and the results of comparative examples 2 to 12 were set to 100 to carry out indexing. The larger the index, the better the tensile strength and elongation at break (breaking strength).
(evaluation 3) abrasion resistance
The abrasion amounts of the load of 44.4N and 1000 revolutions were measured in accordance with JIS K6264-2 using an AKRON abrasion tester (manufactured by An Tian Seiko Co., ltd.) and the results of comparative examples 2 to 12 were normalized to 100. The larger the index, the better the abrasion resistance.
(evaluation 4) viscoelasticity parameter
Viscoelasticity parameters were measured in torsional mode using the viscoelasticity tester "ARES" manufactured by Rheometric Scientific company. The results of the rubber compositions of comparative examples 2 to 12 were set to 100, and the measured values were indexed.
Tan delta measured at 0℃under conditions of a frequency of 10Hz and a deformation of 1% was used as an index of the wet grip performance. The larger the index, the better the wet grip.
Further, tan δ measured at 50 ℃ under the conditions of a frequency of 10Hz and a deformation of 3% was used as an index of fuel economy. The smaller the index, the better the fuel economy.
The elastic modulus (G') measured at 50℃under the conditions of a frequency of 10Hz and a deformation of 3% was used as an index of the steering stability. The larger the index, the better the steering stability.
/>
As shown in tables 17 to 20, it was confirmed that the compounds of examples 2 to 24 to 2 to 46 and examples a to 1 to 2 were low in Mooney viscosity, exhibited good processability, and were excellent in abrasion resistance, handling stability and breaking strength after the production of sulfides, and in balance between low hysteresis loss and wet skid resistance, as compared with comparative examples 2 to 12 to 2 to 22 and comparative examples b to 1 to 2.
Industrial applicability
The modified conjugated diene polymer obtained by the production method of the present invention is industrially useful in the fields of tire treads, interior and exterior articles of automobiles, vibration damping rubbers, conveyor belts, footwear, foam, various industrial applications, and the like.
Claims (55)
1. A process for producing a branched conjugated diene polymer, comprising the steps of:
a polymerization step of polymerizing a conjugated diene compound or copolymerizing a conjugated diene compound with an aromatic vinyl compound using an alkali metal compound or an alkaline earth metal compound as a polymerization initiator, thereby obtaining a conjugated diene polymer having an active terminal;
a branching step of reacting a styrene derivative as a branching agent with an active end of the conjugated diene polymer to introduce a branched structure; and
A step of reacting a conjugated diene polymer having an active end with a branched structure with a compound represented by the following formula (a),
[ chemical 8]
In the formula (a), R 1 ~R 4 Each independently represents an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, R 5 ~R 6 Each independently represents an alkylene group having 1 to 20 carbon atoms;
m and n are integers of 1 to 3, wherein in formula (a), a plurality of R 1 ~R 6 M, n are the same or different;
in the formula (a), X is represented by any one of the following general formulae (b) to (e);
[ chemical 9]
In the formula (b), R 7 Represents a hydrocarbon group having 1 to 20 carbon atoms, and the hydrocarbon group may have a partially branched structure or a cyclic structure; r is R 8 Represents a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and the hydrocarbon group may have a partially branched structure or a cyclic structure;
[ chemical 10]
In the formula (c), R 9 Represents a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and the hydrocarbon group may have a partially branched structure or a cyclic structure;
[ chemical 11]
In the formula (d), R 10 Represents a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atomsThe hydrocarbon group may have a partially branched structure or a cyclic structure;
[ chemical 12]
In the formula (e), R 11 ~R 14 Each independently represents an alkylene group having 1 to 20 carbon atoms; r is R 15 ~R 18 Each independently represents an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and l and o each independently represent an integer of 1 to 3, R in the case where plural numbers are present 15 ~R 18 Each independent;
the styrene derivative is a compound represented by the following formula (1) and/or the following formula (2),
[ chemical 6]
[ chemical 7]
In the formula (1) and the formula (2), R 1 Represents any one selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, and an aryl group having 6 to 20 carbon atoms, and may have a branched structure in a part thereof;
X 1 、X 2 、X 3 is a single bond or contains an organic group selected from any one of the group consisting of carbon, hydrogen, nitrogen, sulfur, and oxygen;
Y 1 、Y 2 、Y 3 represents any one selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, and a halogen atom; the Y is 1 、Y 2 、Y 3 Each independently being the same or different.
2. The method for producing a branched conjugated diene polymer according to claim 1, further comprising a step of adding a conjugated diene compound and/or an aromatic vinyl compound to the reaction system at the time of and/or after the branching step.
3. The method for producing a branched conjugated diene polymer according to claim 1 or 2, further comprising a reaction step of reacting a polymerization terminator with the active end of the conjugated diene polymer obtained in the branching step.
4. The method for producing a branched conjugated diene polymer according to claim 3, wherein the polymerization terminator has a nitrogen atom-containing group.
5. The method for producing a branched conjugated diene polymer according to claim 3, wherein the polymerization terminator is an alkoxide compound having a nitrogen atom-containing group.
6. The method for producing a branched conjugated diene polymer according to claim 1, wherein R in the formula (1) 1 Is a hydrogen atom, Y 1 Is any one selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, and a halogen atom.
7. The method for producing a branched conjugated diene polymer according to claim 1, wherein Y in the formula (2) 2 Is any one selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, and a halogen atom.
8. The method for producing a branched conjugated diene polymer according to claim 1, wherein R in the formula (1) 1 Is a hydrogen atom, Y 1 Is an alkoxy group having 1 to 20 carbon atoms or a halogen atom.
9. The method for producing a branched conjugated diene polymer according to claim 1, wherein Y in the formula (2) 2 Is an alkoxy group having 1 to 20 carbon atoms or a halogen atom, Y 3 Is an alkoxy group having 1 to 20 carbon atoms or a halogen atom.
10. The method for producing a branched conjugated diene polymer according to claim 1, wherein R in the formula (1) 1 Is a hydrogen atom, Y 1 An alkoxy group having 1 to 20 carbon atoms.
11. The method for producing a branched conjugated diene polymer according to claim 1, wherein R in the formula (1) 1 Is a hydrogen atom, X 1 Is a single bond, Y 1 An alkoxy group having 1 to 20 carbon atoms.
12. The method for producing a branched conjugated diene polymer according to claim 1, wherein X in the formula (2) 2 Is a single bond, Y 2 Is an alkoxy group having 1 to 20 carbon atoms or a halogen atom, X 3 Is a single bond, Y 3 Is an alkoxy group having 1 to 20 carbon atoms or a halogen atom.
13. The method for producing a branched conjugated diene polymer according to claim 1, wherein the compound represented by the formula (1) is selected from the group consisting of trimethoxy (4-vinylphenyl) silane, triethoxy (4-vinylphenyl) silane, tripropoxy (4-vinylphenyl) silane, tributoxy (4-vinylphenyl) silane, triisopropoxy (4-vinylphenyl) silane, trimethoxy (3-vinylphenyl) silane, triethoxy (3-vinylphenyl) silane, tripropoxy (3-vinylphenyl) silane, tributoxy (3-vinylphenyl) silane, triisopropoxy (3-vinylphenyl) silane, trichloro (4-vinylphenyl) silane, trimethoxy (4-vinylbenzyl) silane, triethoxy (4-vinylbenzyl) silane.
14. The method for producing a branched conjugated diene polymer according to claim 1, wherein the compound represented by the formula (2) is selected from the group consisting of 1, 1-bis (4-trimethoxysilylphenyl) ethylene, 1-bis (4-triethoxysilylphenyl) ethylene, 1-bis (4-tripropoxysilylphenyl) ethylene, 1-bis (4-tripentyloxysilylphenyl) ethylene, and 1, 1-bis (4-triisopropoxysilylphenyl) ethylene.
15. The process for producing a branched conjugated diene polymer according to claim 1, wherein the branching agent is added at a point in time when the conversion of the raw material is 20% or more after the addition of the polymerization initiator.
16. The process for producing a branched conjugated diene polymer according to claim 1, wherein the branching agent is added at a point in time when the conversion of the raw material after the addition of the polymerization initiator is 50% or more.
17. The process for producing a branched conjugated diene polymer according to claim 1, wherein the branching agent is added at a point in time when the conversion of the raw material after the addition of the polymerization initiator is 75% or more.
18. The method for producing a branched conjugated diene polymer according to claim 1, wherein the molar ratio of the branching agent to the amount of the polymerization initiator is one percent or more and one half or less.
19. The method for producing a branched conjugated diene polymer according to claim 1, wherein the molar ratio of the branching agent to the polymerization initiator is one-twelfth or one-eighth or less.
20. The method for producing a branched conjugated diene polymer according to claim 2, wherein the additional amount of the conjugated diene compound and/or the aromatic vinyl compound is 5% or more of the total amount of the conjugated diene compound used in the polymerization step.
21. The method for producing a branched conjugated diene polymer according to claim 2, wherein the additional amount of the conjugated diene compound and/or the aromatic vinyl compound is 15% or more of the total amount of the conjugated diene compound used in the polymerization step.
22. The method for producing a branched conjugated diene polymer according to claim 2, wherein the additional amount of the conjugated diene compound and/or the aromatic vinyl compound is 25% or more of the total amount of the conjugated diene compound used in the polymerization step.
23. The method for producing a branched conjugated diene polymer according to claim 1, wherein the branched conjugated diene polymer obtained has a branched structure of 3 to 24 branches.
24. The method for producing a branched conjugated diene polymer according to claim 1, wherein the branched conjugated diene polymer obtained has a branched structure of 5 to 18 branches.
25. The method for producing a branched conjugated diene polymer according to claim 1, wherein the branched conjugated diene polymer obtained is a copolymer of a conjugated diene monomer, an aromatic vinyl monomer and a branching agent, and the amount of the conjugated diene bonded in the copolymer is 40 mass% or more and 100 mass% or less.
26. The method for producing a branched conjugated diene polymer according to claim 1, wherein the amount of the bonded aromatic vinyl group in the obtained branched conjugated diene polymer is 0 mass% or more and 60 mass% or less.
27. The method for producing a branched conjugated diene polymer according to claim 1, wherein the amount of the bonded aromatic vinyl group in the obtained branched conjugated diene polymer is 20 mass% or more and 45 mass% or less.
28. The method for producing a branched conjugated diene polymer according to claim 1, wherein the amount of vinyl groups bonded to conjugated diene bonding units in the resulting branched conjugated diene polymer is 10 mol% or more and 75 mol% or less.
29. The method for producing a branched conjugated diene polymer according to claim 1, wherein the amount of vinyl groups bonded to the conjugated diene bonding units in the resultant branched conjugated diene polymer is 20 mol% or more and 65 mol% or less.
30. The method for producing a branched conjugated diene polymer according to claim 1, wherein the modification ratio of the obtained branched conjugated diene polymer is 60% by mass or more.
31. The method for producing a branched conjugated diene polymer according to claim 1, wherein the compound represented by the formula (a) is a compound represented by the following formulas (A-1) to (A-16),
[ chemical 24]
[ chemical 25]
[ chemical 26]
In the formulas (A-1) to (A-16), et is ethyl, and Me is methyl.
32. The method for producing a branched conjugated diene polymer according to claim 1, wherein the compound represented by the formula (a) is used in a proportion of 0.01 mol or more and less than 2.0 mol based on 1 mol of the metal atom involved in the polymerization, which is contained in the polymerization initiator.
33. The method for producing a branched conjugated diene polymer according to claim 3, wherein the polymerization terminator is a 2-functional reactive compound.
34. The method for producing a branched conjugated diene polymer according to claim 3, wherein the branched conjugated diene polymer obtained has a branched structure of 6 to 36 branches.
35. The method for producing a branched conjugated diene polymer according to claim 3, wherein the branched conjugated diene polymer obtained has a branched structure of 12 to 20 branches.
36. The method for producing a branched conjugated diene polymer according to claim 3, wherein the total number of branching points in the obtained branched conjugated diene polymer is 2 or more.
37. The method for producing a branched conjugated diene polymer according to claim 3, wherein the total number of branching points in the obtained branched conjugated diene polymer is 4 or more.
38. A branched conjugated diene polymer which is a reaction product of a conjugated diene polymer having an active end with a branched structure and a compound represented by the following formula (a) and which is obtained by reacting a styrene derivative as a branching agent with the active end of a conjugated diene polymer,
[ chemical 8]
In the formula (a), R 1 ~R 4 Each independently represents an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, R 5 ~R 6 Each independently represents an alkylene group having 1 to 20 carbon atoms;
m and n are integers of 1 to 3, wherein in formula (a), a plurality of R 1 ~R 6 M, n are the same or different;
in the formula (a), X is represented by any one of the following general formulae (b) to (e);
[ chemical 9]
In the formula (b), R 7 Represents a hydrocarbon group having 1 to 20 carbon atoms, and the hydrocarbon group may have a partially branched structure or a cyclic structure; r is R 8 Represents a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and the hydrocarbon group may have a partially branched structure or a cyclic structure;
[ chemical 10]
In the formula (c), R 9 Represents a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and the hydrocarbon group may have a partially branched structure or a cyclic structure;
[ chemical 11]
In the formula (d), R 10 Represents a hydrocarbon group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and the hydrocarbon group may have a partially branched structure or a cyclic structure;
[ chemical 12]
In the formula (e), R 11 ~R 14 Each independently represents an alkylene group having 1 to 20 carbon atoms; r is R 15 ~R 18 Each independently represents an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, and l and o each independently represent an integer of 1 to 3, R in the case where plural numbers are present 15 ~R 18 Each of which is independent of the other,
the styrene derivative is a compound represented by the following formula (1) and/or the following formula (2),
[ chemical 6]
[ chemical 7]
In the formula (1) and the formula (2), R 1 Represents any one selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, and an aryl group having 6 to 20 carbon atoms, and may have a branched structure in a part thereof;
X 1 、X 2 、X 3 Is a single bond or contains an organic group selected from any one of the group consisting of carbon, hydrogen, nitrogen, sulfur, and oxygen;
Y 1 、Y 2 、Y 3 represents any one selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, and a halogen atom; the Y is 1 、Y 2 、Y 3 Each independently being the same or different.
39. The branched conjugated diene polymer according to claim 38, wherein the compound represented by formula (a) is OR 1 and/OR OR 3 Has a branched structure.
40. The branched conjugated diene polymer according to claim 38, wherein the compound represented by the formula (a) is a compound represented by the following formulas (A-1) to (A-16),
[ chemical 24]
[ chemical 25]
[ chemical 26]
In the formulas (A-1) to (A-16), et is ethyl, and Me is methyl.
41. The branched conjugated diene polymer according to claim 38, wherein the modification ratio is 60% by mass or more.
42. The branched conjugated diene polymer according to claim 38, wherein the modification ratio is 80% by mass or more.
43. The branched conjugated diene polymer according to claim 38, wherein the branched structure is 6 to 36 branches.
44. The branched conjugated diene polymer according to claim 38, wherein the branched structure is 12 to 20 branches.
45. The branched conjugated diene polymer according to claim 38, wherein the total number of branching points is 2 or more.
46. The branched conjugated diene polymer according to claim 38, wherein the total number of branching points is 4 or more.
47. A rubber composition comprising:
a rubber component comprising 10 mass% or more of the branched conjugated diene polymer according to any one of claims 38 to 46; and
the filler is 5.0 to 150 parts by mass based on 100 parts by mass of the rubber component.
48. The rubber composition as described in claim 47, wherein the rubber component contains 20 mass% or more and 90 mass% or less of the branched conjugated diene polymer according to any one of claims 38 to 46.
49. The rubber composition as described in claim 47, wherein the rubber component contains 50 mass% or more and 80 mass% or less of the branched conjugated diene polymer according to any one of claims 38 to 46.
50. The rubber composition as described in claim 47, wherein the filler comprises a silica-based inorganic filler.
51. A method for producing a rubber composition, comprising the steps of:
A step of obtaining a branched conjugated diene polymer by the production method according to any one of claims 1 to 37;
a step of obtaining a rubber component containing 10 mass% or more of the branched conjugated diene polymer; and
a step of obtaining a rubber composition containing 5.0 parts by mass to 150 parts by mass of a filler per 100 parts by mass of the rubber component.
52. The method for producing a rubber composition as defined in claim 51, wherein the rubber component contains 20 mass% or more and 90 mass% or less of the branched conjugated diene polymer.
53. The method for producing a rubber composition as defined in claim 51, wherein the rubber component contains 50 mass% or more and 80 mass% or less of the branched conjugated diene polymer.
54. The method for producing a rubber composition as defined in claim 51, wherein the filler comprises a silica-based inorganic filler.
55. A method for manufacturing a tire, comprising the steps of:
a step of obtaining a rubber composition by the method for producing a rubber composition according to any one of claims 51 to 54; and
and a step of molding the rubber composition to obtain a tire.
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CN107849160A (en) * | 2015-12-24 | 2018-03-27 | 株式会社Lg化学 | Modified conjugated diene is birdsed of the same feather flock together compound, its preparation method and modifying agent |
CN108368195A (en) * | 2016-11-21 | 2018-08-03 | 株式会社Lg化学 | Modifying agent, the preparation method of the modifying agent and the modified conjugated diene Type of Collective object comprising the modifying agent |
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