JP6774782B2 - Method for Producing Modified Diene Polymer - Google Patents

Description

The present invention relates to a method for producing a modified conjugated diene polymer. More specifically, the present invention
The present invention relates to a method for continuously producing a specific modified diene-based polymer in which an initiator solution containing aminolithium is prepared by a specific continuous method and subjected to continuous polymerization.

In recent years, there has been an increasing demand for fuel efficiency in automobiles, and as one of the methods to solve this, research on rubber-like polymers aiming at low hysteresis loss has been actively conducted for rubber for tires, especially rubber for tread. ing. For this purpose, research on a method for producing a modified polymer focusing on a polymer having a molecular structure whose terminal is a tertiary amine is also being carried out.

Under such circumstances, for example, Patent Documents 1 and 2 describe a modified diene polymer having an amino group at the starting end, which is obtained by using an alkali metal amide as a polymerization initiator and adding a specific compound to carry out a polymerization reaction. It is disclosed. Further, Patent Documents 3 to 4 disclose similar modified diene-based polymers obtained by producing an alkali metal amide in the presence of a monomer in a batch polymerization polymerization reactor.

Japanese Unexamined Patent Publication No. 50-79590 Japanese Unexamined Patent Publication No. 54-2484 Japanese Unexamined Patent Publication No. 06-199921 Japanese Unexamined Patent Publication No. 09-110942

In the above-mentioned conventional technique, an alkali metal amide such as aminolithium tends to form a cluster composition such as a trimeric or tetramer which is sparingly soluble in a solvent during storage, so that there is a problem that the polymerization start time is not aligned. In order to avoid this, there is no choice but to select a method of adding a specific compound or a method of producing an alkali metal amide in a polymerization reactor under the restricted conditions in batch polymerization. In such a batch type polymerization method, the production efficiency of the modified diene polymer is low, and there is room for improvement in performance such as fuel efficiency of the obtained modified diene polymer.

The present invention has been made in view of the above-mentioned problems of the prior art, and a modified diene polymer capable of efficiently obtaining a modified diene polymer having excellent wet grip and fuel saving properties when used as a vulcanized product can be efficiently obtained. An object of the present invention is to provide a method for continuously producing a system polymer.

As a result of diligent research to solve the above problems, the present inventors used a mixing means and averaged in the step of preparing an initiator that continuously reacts an organolithium with a secondary amine in an inert organic solvent. We have found that the above problems can be solved by setting the residence time to 1 hour or less, and have completed the present invention.

That is, the present invention is as follows.
[1]
A preparation step of continuously reacting organolithium with a secondary amine in an inert organic solvent to obtain an initiator solution containing aminolithium.
The step of continuously introducing the initiator solution into the polymerizer and
A step of continuously introducing a polymerization monomer containing 50 to 100 parts of a conjugated diene monomer and 50 to 0 parts of a copolymerizable monomer into the polymerizer.
A polymerization step of homopolymerizing or copolymerizing the polymerization monomer in an inert organic solvent to obtain a polymer solution.
A step of continuously discharging the polymer solution from the polymerizer and
Including
The preparation step includes a first introduction section for introducing the organolithium, a second introduction section for introducing the secondary amine, a derivation section for deriving the initiator solution, and the organolithium and the secondary. It is carried out in a reactor comprising a mixing means for stirring the amine and the inert organic solvent.
A method for continuously producing a modified diene polymer, wherein the average residence time of the initiator solution in the preparation step is 1 hour or less.
[2]
The method for continuously producing a modified diene polymer according to [1], wherein the reactor is a tank-type reactor including a rotary stirrer as the mixing means.
[3]
The rotary stirrer is arranged perpendicular to the tank reactor.
The first introduction portion and the second introduction portion are located below the lowermost end of the stirring blade in the rotary stirrer, and the lead-out portion is located above the uppermost end of the stirring blade. The method for continuously producing a modified diene polymer according to [2].
[4]
The method for continuously producing a modified diene polymer according to [1], wherein the mixing means is a static mixer.
[5]
In the preparation step, the temperature difference between the first introduction section and the second introduction section and the lead-out section is detected, and the reaction rate between the organolithium and the secondary amine is adjusted [1] to [4]. The method for continuously producing a modified polymer according to any one of.
[6]
A step of inactivating impurities contained in the polymerization monomer by mixing an organometallic compound with the polymerization monomer or a solution of the polymerization monomer.
The step of introducing the polymerization monomer or the solution of the polymerization monomer after the inactivation into the polymerizer, and
The method for continuously producing a modified diene polymer according to any one of [1] to [5], further comprising.
[7]
A modification step of continuously adding a terminal modifier to the polymer solution, and
A step of removing the solvent from the polymer solution that has undergone the modification step, and a step of removing the solvent.
The method for continuously producing a modified diene polymer according to any one of [1] to [6], further comprising.
[8]
The continuous modified diene polymer according to any one of [1] to [7], wherein the lithium concentration of the initiator solution calculated by the following formula in the preparation step is 0.01% to 3%. Manufacturing method.
Lithium concentration (%) = (average supply rate of the organic lithium) / (total average supply rate of all components supplied to the reactor) × (lithium atomic weight) / (molecular weight of the organic lithium) × 100

According to the present invention, a modified diene polymer having excellent wet grip and fuel efficiency when made into a vulcanized product can be efficiently obtained.

It is explanatory drawing which shows an example of the tank type reactor in this embodiment.

Hereinafter, embodiments for carrying out the present invention (hereinafter, referred to as “the present embodiment”) will be described in detail. The present invention is not limited to the present embodiment, and can be variously modified and implemented within the scope of the gist thereof. Moreover, the dimensional ratio of the drawing is not limited to the ratio shown in the drawing.

The method for continuously producing a modified diene polymer according to the present embodiment includes a preparation step of continuously reacting organic lithium with a secondary amine in an inert organic solvent to obtain an initiator solution containing aminolithium. , The step of continuously introducing the initiator solution into the polymer, and the polymerization monomer containing 50 to 100 parts of the conjugated diene monomer and 50 to 0 parts of the copolymerizable monomer are continuously added. A step of introducing the polymer solution into the polymer, a polymerization step of homopolymerizing or copolymerizing the polymerization monomer in an inert organic solvent to obtain a polymer solution, and a polymerization step of obtaining the polymer solution from the polymer. The preparation step includes a step of continuously discharging the organic lithium, a first introduction section for introducing the organic lithium, a second introduction section for introducing the secondary amine, and the initiator solution. It is carried out in a reactor including a lead-out unit and a mixing means for stirring the organic lithium, the secondary amine and the inert organic solvent, and the average residence time of the initiator solution in the preparation step is within 1 hour. Is.
Due to this structure, according to the method for continuously producing a modified diene polymer according to the present embodiment, the yield (that is, the conversion rate of the secondary amine) in the reaction for preparing aminolithium is high. Moreover, since the formation of a sparingly soluble trimer or tetramer cluster composition can be suppressed, a modified diene polymer having an amino group at the polymerization initiation position can be efficiently obtained, and the modified diene polymer can be efficiently obtained. Is excellent in wet grip and fuel saving when it is made into a vulcanized product. The modified diene polymer obtained as described above can be a vulcanized rubber composition suitable for tire rubbers, anti-vibration rubbers, footwear, etc., which are oriented toward low hysteresis loss. In particular, when the vulcanized rubber composition contains a reinforcing filler and the reinforcing filler is settling silica, or settling silica and carbon black, the effect becomes more remarkable.

The method for continuously producing a modified diene polymer according to the present embodiment is a method for continuously producing a modified diene polymer, and in particular, a production method in which an initiator preparation step and a polymerization step are continuously performed. It is characteristic that there is. Here, the "continuous production method" is a method in which the raw materials for the reaction are continuously supplied to the reaction system and the reaction product is continuously discharged to the outside of the reaction system. That is, the method of performing polymerization each time, such as supplying a predetermined amount of raw materials to the reaction system, advancing the reaction, discharging the reaction product to the outside of the reaction system, and then supplying the predetermined amount of raw materials to the reaction system again is described in this method. It does not correspond to the continuous manufacturing method referred to in the embodiment.

<Preparation process>
The preparation step in the present embodiment is a step of continuously reacting organolithium with a secondary amine in an inert organic solvent to obtain an initiator solution containing aminolithium.

Organolithium in this embodiment includes those generally known as compounds in which carbon of an organic group and lithium are bonded. The organic lithium is preferably an aliphatic lithium having 1 to 20 carbon atoms, an alicyclic lithium, and an aromatic lithium, and may be a monolithium compound or a polylithium compound. Specific examples include, but are not limited to, methyl lithium, ethyl lithium, propyl lithium, n-butyl lithium, sec-butyl lithium, tert-butyl lithium, hexyl lithium, octyl lithium and other alkyl lithium, vinyl lithium and propenyl lithium. Aromatic lithium represented by alkenyl lithium such as phenyl lithium, trill lithium, lithium naphthylide, etc., tetramethylene dilithium, pentamethylene dilithium, hexamethylene dilithium, decamethylene Examples thereof include alkylene dilithium represented by dilithium and the like. Of these, n-butyllithium and sec-butyllithium are more preferable from the viewpoints of storage stability, solubility in organic solvents, and industrial availability.

The secondary amine in the present embodiment is not particularly limited, and various known ones can be used, but the imine compounds represented by the general formula (A), the general formula (1) and the general formula (2), and the general It is preferably at least one compound selected from the amine compounds represented by the formula (B).

(In the general formula (A), X is a hydrocarbylene group.)

(In the general formulas (1) to (2), R ¹ is a hydrocarbylene group, and Q is -N (-A ¹ )-, -O-, -P (-A ¹ )-, -Si ( -A ¹ ) (-A ² )-, -Sn (-A ¹ ) (-A ² )-, or -C (-A ¹ ) (-A ² )-where A ¹ is active. A substituted or unsubstituted hydrocarbyl group or hydrocarbylene group which does not have a hydrogen atom and may contain one or more atoms selected from the group consisting of N, P, O, S, Si and Sn. A ² Is a hydrocarbyl group or a hydrocarbylene group. A ¹ and A ² may be bonded to form a ring. A plurality of R ¹ and Q present in the formula may be the same or different, respectively. .)

(R ² and R ³ represent hydrocarbon groups having 1 to 20 carbon atoms selected from each of the aliphatic, alicyclic, and aromatic hydrocarbon groups, and may be the same or different.)

The X (hydrocarbylene group) in the general formula (A) is not limited to the following, and examples thereof include an alkylene group, an arylene group, and an aralkylene group. The number of carbon atoms of the hydrocarbylene group is not particularly limited, but is, for example, 3 to 20.

The R ¹ (hydrocarbylene group) in the general formulas (1) and (2) is not limited to the following, and examples thereof include a methylene group, an alkylene group, an arylene group, and an aralkylene group. The number of carbon atoms of the hydrocarbylene group is not particularly limited, but is, for example, 1 to 10. In A ¹ in the general formulas (1) and (2), "substitution or unsubstituted which may contain one or more atoms selected from the group consisting of N, P, O, S, Si and Sn" means Indicates that a part of the carbon atom in the hydrocarbyl group or the hydrocarbylene group may or may not be substituted with N, P, O, S, Si or Sn.

Examples of the hydrocarbyl group represented by A ¹ contained in Q in the general formulas (1) and (2) include an alkyl group, an aryl group, an aralkyl group and the like. The number of carbon atoms of the hydrocarbyl group is not particularly limited, but is, for example, 1 to 10.

The hydrocarbylene group represented by A ¹ contained in Q in the general formulas (1) and (2) is not limited to the following, and examples thereof include a methylene group, an alkylene group, an arylene group, and an aralkylene group. Be done. The number of carbon atoms of the hydrocarbylene group is not particularly limited, but is, for example, 1 to 10.

The hydrocarbyl group represented by A ² contained in Q in the general formulas (1) and (2) is not limited to the following, and examples thereof include an alkyl group, an aryl group, and an aralkyl group. The hydrocarbyl group preferably has 1 to 6 carbon atoms.

The hydrocarbylene group represented by A ² contained in Q in the general formulas (1) and (2) is not limited to the following, but for example, a methylene group, an alkylene group, an arylene group, an aralkylene group and the like. Can be mentioned. The hydrocarbylene group preferably has 1 to 6 carbon atoms.

The imine compound represented by the general formula (A) is not limited to the following, and is, for example, trimethyleneimine, pyrrolidine, piperidine, hexamethyleneimine, heptamethyleneimine, octamethyleneimine, decamethyleneimine, dodecamethyleneimine. , 2-Methylpiperidin, 3-methylpiperidin, 4-methylpiperidin, 3,5-dimethylpiperidin, 2-ethylpiperidin and the like.

The imine compound represented by the general formula (1) is not limited to the following, and is, for example, N-methylpiperazine, N-ethylpiperazine, N, N-dimethyl-3-piperazinopropylamine, 1-(. 2,4,6-trimethylbenzyl) piperidine, 1- (2-pyridyl) piperidine, N-methylimidazolidine, N-ethylimidazolidine, 4-piperidinopiperidin, morpholine, phenoxazine, 5-butyl-1- Aza-5-phosphaspiro [5.5] undecane, 4,4-dimethyl-1,4-azasilane, 4,4-dibutyl-1,4-azastanninan and the like can be mentioned.

The imine compound represented by the general formula (2) is not limited to the following, and examples thereof include 3,5-bis (dimethylamino) piperidine and 3,5-dipiperidinopiperidine.

Among the amine compounds of the general formula (B), amine compounds having a group in which R ² and R ³ are selected from aliphatic, alicyclic, and aromatic hydrocarbon groups having 1 to 10 carbon atoms are preferable, and specific examples thereof. The, but not limited to, dimethylamine, diethylamine, dipropylamine, di-n-butylamine, diisobutylamine, dipentylamine, dihexylamine, diheptylamine, dioctylamine, diallylamine, dicyclohexylamine, butylisopropylamine, di Benzylamine, methylbenzylamine, methylhexylamine, ethylhexylamine and the like can be mentioned. Of these, amines having a group in which R ² and R ³ are selected from aliphatic hydrocarbon groups having 1 to 10 carbon atoms are more preferable.

The secondary amine in the present embodiment is selected from the above general formulas (A), imine compounds represented by the general formulas (1) and (2), and amine compounds represented by the general formula (B). One kind or two or more kinds can be used.

<Inactive organic solvent>
The inert organic solvent in the present embodiment includes those generally known as organic solvents that are inert to organolithium and secondary amines. A preferred inert organic solvent is a hydrocarbon solvent. The hydrocarbon solvent is not limited to the following, and examples thereof include saturated hydrocarbons and aromatic hydrocarbons. More specifically, aliphatic hydrocarbons such as butane, pentane, hexane, pentane and heptane; alicyclic hydrocarbons such as cyclopentane, cyclohexane, methylcyclopentane and methylcyclohexane; aromatic hydrocarbons such as benzene, toluene and xylene. Hydrocarbons composed of hydrogen and a mixture thereof can be used. In particular, hexane, cyclohexane or a mixture thereof is preferable because of the solubility in each step and the ease of removing the solvent in the finishing step described later, which can be commonly used in the preparation step and the polymerization step described later.

In the present embodiment, the organolithium and the secondary amine are preferably a solution of either or each of the inert organic solvent.

In the preparation step of the present embodiment, when the organic lithium and the secondary amine are continuously reacted in the inert organic solvent, the first introduction part for introducing the organic lithium and the second introduction part for introducing the secondary amine are introduced. The average residence time of the initiator solution is 1 by using a reactor including an introduction unit, a derivation unit for deriving the initiator solution, and a mixing means for stirring the organolithium, the secondary amine, and the inert organic solvent. Must be within hours. As the mixing means, it is necessary that the mixing means is sufficient to quickly mix and react the organolithium and the secondary amine, and a conventionally known mixing means can be used.

The reactor in the present embodiment is not particularly limited, and examples thereof include a tank reactor and a tubular reactor. Preferred reactors in this embodiment are a tank reactor including a rotary stirrer as a mixing means and a tubular reactor including a static mixer as a mixing means. When the above-mentioned tank reactor is used, a high amino lithium yield tends to be stably achieved even with fluctuations in the reaction rate.
When a tank reactor is used, the stirring power per unit volume is preferably 0.1 to 10 kW / m ³ from the viewpoint of further promoting the progress of the reaction. Here, the stirring power is the power required for stirring, and can be easily obtained by measuring the power consumption during mixing. From the same viewpoint, when a tubular reactor, that is, a static mixer is used, the Reynolds number can be set to a turbulent region (preferably Re = 4000 or more), and the inner diameter and the number of elements can be adjusted as appropriate. preferable. For example, the linear velocity is determined from the total flow rate assumed to be the basic physical properties of the supplied substance and the inner diameter of the reactor, and the Reynolds number is determined. The number of elements can be appropriately selected according to the region of the Reynolds number. Further, the residence time can be estimated in advance from the reaction rate of the reaction raw material to be used, the pipe length corresponding to the residence time can be calculated, and the required number of elements can be determined according to the pipe length. It is preferable to select the inner diameter of the reactor and the number of elements according to the above procedure, and also consider the pressure loss at that time.

In the preparation step of the present embodiment, it is essential that the average residence time of the initiator solution is 1 hour or less when the organolithium and the secondary amine are continuously reacted in the inert organic solvent. The average residence time means the average residence time from the time when the organolithium and the secondary amine are mixed in the reactor to the outlet of the reactor. The average residence time can be calculated as a value obtained by dividing the reactor volume (volume excluding the volume occupied by the mixing means in the reactor) by the sum of the average supply rate of the secondary amine and the average supply rate of the solvent. More specifically, it can be measured by the method described in Examples described later. The average residence time is preferably 1 second or more, more preferably 2 seconds or more, and preferably 40 minutes or less, more preferably 30 minutes or less. When the average residence time is within the above range, it is difficult to form a trimeric or tetramer cluster composition that is sparingly soluble in the solvent, and precipitation, clogging, etc. occur in the piping, and the starting speed in the next polymerization step. There is no delay or variation. That is, when the average residence time is within the above range, a modified diene polymer having an amino group at the starting position can be efficiently obtained. The average supply rate means the supply rate per unit time, and when the rate changes with time, it is the average value.
The average residence time can be adjusted within the above range by, for example, the volume of the reactor, the concentration of lithium in the initiator solution (that is, the amount of organic lithium relative to the total supply amount), and the like. Specifically, when the amount of lithium (rate) required in the polymerization step on the downstream side fluctuates, the reaction rate in the preparation step fluctuates, and as a result, the average residence time tends to fluctuate. Here, the amount of lithium (rate) required in the downstream polymerization step is determined according to the target molecular weight of the polymer obtained in the polymerization step. More specifically, the lithium amount rate required in the polymerization step is y (kg / min), the volume of the reactor in the preparation step is V (L), and the lithium supply rate (average supply rate) to the reactor is x. Assuming that (kg / min) and the concentration of lithium in the initiator solution (in the reactor) is d (kg / L), y = xxd holds. If the average residence time is θ, then θ = V / x = (d × V) / y. Here, from the viewpoint of making the molecular weight of the polymer to be produced substantially uniform, y is usually constant and V is also constant. Therefore, as can be seen from the above equation, θ is proportional to d. Therefore, as the lithium concentration increases, the average residence time also tends to increase.
Specifically, the lithium concentration in the present embodiment is (average supply rate of organic lithium) / (total average supply rate of all components supplied to the reactor) × (lithium atomic weight) / (organolithium molecular weight) × 100. As described above, it may be determined according to the molecular weight of the polymer desired in the polymerization step, but it is preferably 0.01% to 3%, more preferably 0.1% to 2 It is 5.5%. Within the above range, it tends to be possible to more effectively prevent the formation of a sparingly soluble trimer or tetramer cluster composition in the initiator solution, resulting in precipitation, clogging, etc. in the piping. There is a tendency that the occurrence and the delay of the start rate and the occurrence of variation in the next polymerization step can be prevented more effectively.

The shorter the average residence time when the initiator solution is transferred from the reactor used in the preparation step to the polymerizer used in the polymerization step in the present embodiment is better, but preferably within 10 minutes, more preferably within 5 minutes. .. As a means for shortening the average residence time from the reactor to the polymer, it is possible to select a means for adding a solvent after leaving the reactor and feeding the solvent to the polymer along with the flow of the solvent.

When a tank reactor provided with a rotary stirrer is used in the initiator preparation step of the present embodiment, the rotary stirrer is arranged perpendicular to the tank reactor from the viewpoint of further improving the reaction efficiency, and the first The introduction part and the second introduction part of the rotary stirrer are located below the lowermost end of the stirring blade in the rotary stirrer, and the lead-out part is located above the uppermost end of the stirring blade. Is preferable. In the above, the "lower side" means the first introduction part and the second introduction part side in the positional relationship between the first introduction part and the second introduction part and the out-licensing part. Further, the “upper side” means the out-licensing part side in the positional relationship between the first introduction part and the second introduction part and the out-licensing part. Further, "vertically arranged" means that the main body of the rotary stirrer extends substantially perpendicular to the width direction in the tank reactor. In other words, "vertical" is substantially parallel to the above-mentioned direction from "lower side" to "upper side" (the traveling direction of organolithium and secondary amine in the tank reactor).
An explanatory diagram showing an example of a tank reactor having the above configuration is shown in FIG. The tank reactor 10 in the present embodiment includes a first introduction unit 1 and a second introduction unit 2 for supplying organic lithium and a secondary amine as reaction raw materials into the reaction system, and reacts. The raw material reacts while being stirred by the rotary stirrer 6 and is led out from the out-licensing unit 3 as an initiator solution.
The rotary stirrer 6 may include a plurality of stirring blades along the vertical direction of the rotation shaft, and in FIG. 1, the stirring blade uppermost portion 4 located at the uppermost end and the stirring blade most located at the lowermost end are located in FIG. Only the bottom 5 is shown.
In FIG. 1, the first introduction unit 1 and the second introduction unit 2 are located below the lowermost portion 5 of the stirring blade in the rotary stirrer 6, and the lead-out unit 3 is located below the uppermost portion 4 of the stirring blade. It is located on the upper side. When the tank reactor 10 has such a configuration, the reaction efficiency tends to be further improved.

In the present embodiment, from the viewpoint of reaction efficiency, the tank reactor 10 has a first introduction unit 1 and a second introduction unit 2 based on the length L of the tank reactor and the diameter D of the tank reactor. It is preferable to adjust the positional relationship between the lead-out unit 3 and the rotary stirrer 6. Specifically, the first introduction unit 1 and the second introduction unit 2 are preferably located below L / 10 or more of the lowermost portion 5 of the stirring blade, and the lead-out unit 3 is located below the uppermost portion 4 of the stirring blade. It is preferably located at a height above L / 10.

In the preparation step of the present embodiment, from the viewpoint of reaction efficiency, the tank reactor 10 has a ratio (L / D) of the length L of the tank reactor to the diameter D of the tank reactor 2 or more. Alternatively, it is preferable to form a shape that prevents short pass or backmix by means such as inserting a partition plate into a tank reactor to form a multi-stage shape.

In the preparation step of the present embodiment, a static mixer can also be used as the mixing means. In that case, the pressure loss per unit volume is preferably 0.01 to 10 kW / m ³ , more preferably the number of mixed elements is 4 to 100, and the Reynolds number is in the turbulent flow region (2300 or more). It is a reactor, and the reactor is more preferably a tubular reactor. In that case, the reaction efficiency tends to be more stable and higher.

In the preparation step of the present embodiment, it is preferable to detect the temperature difference between the first introduction section and the second introduction section and the extraction section, and adjust the reaction rate between the organolithium and the secondary amine. In that case, the modified diene polymer tends to be obtained more efficiently and stably. The temperature of the first introduction part and the second introduction part is the temperature of the first introduction part and the second introduction part in the reactor, or the average temperature of the temperature of the organic lithium and the secondary amine or their respective solutions. Can be managed. Further, the temperature of the lead-out unit can be managed as the temperature of the lead-out unit in the reactor or the temperature in the discharge pipe. The temperature difference between the first introduction section and the second introduction section and the extraction section is affected by the concentrations of the organic lithium and the secondary amine because it is diluted with the inert organic solvent, but is preferably 1. The temperature is in the range of ° C. to 30 ° C., more preferably 2 ° C. to 20 ° C. When the above temperature difference fluctuates, when the feed rate of any of the organic lithium or secondary amine, inert organic solvent, etc. fluctuates, when the average residence time fluctuates, when the reaction rate fluctuates. , The amount of heat released to the outside of the reactor may fluctuate. The average temperature is a temperature represented by ΣMnCpnTn / ΣMnCpn. Here, Mn, Cpn, and Tn represent the mass, specific heat, and temperature of the component n, respectively.

In the preparation step of the present embodiment, a polar compound that can be used as a randomizer in the polymerization described later or a part thereof may be added together with the raw material. In that case, the reaction between the organic lithium and the secondary amine tends to be promoted more.

In the present embodiment, the feed ratio of the organic lithium to the secondary amine is preferably such that the molar ratio of the NH group of the lithium of the organic lithium to the secondary amine is 1: 0.1 to 1: 1.5, and 1: 0.2 to 1 is more preferable, and 1: 0.4 to 0.9 is even more preferable. Within the above range, a modified diene polymer having excellent performance tends to be obtained more efficiently.

In this embodiment, organolithium reacts with a secondary amine to obtain an initiator solution containing aminolithium. Here, the initiator solution may contain aminolithium and a part of unreacted organic lithium, and the conversion rate of the secondary amine is preferably 90% or more, more preferably 95% or more, still more preferably. It is assumed that the residual amount of the secondary amine is very small or hardly contained. When the amount of the residual secondary amine is small, the chain transfer is small in the polymerization step, the expansion of the molecular weight distribution is suppressed, and the yield of the modified diene polymer, that is, the modification rate which is the mass ratio of the modified diene polymer in the whole polymer. Tends to improve. The conversion rate of the secondary amine can be measured by the method described in Examples described later.

In this embodiment, organolithium and secondary amines, or their respective solutions, are preferably introduced into the reactor from separate nozzles. Further, it is preferable that these are introduced into a sufficient stirring region immediately after the introduction of the reactor. In the above case, the formation of solvent-insoluble precipitates tends to be prevented more effectively.

In the present embodiment, a step of continuously introducing the obtained initiator solution containing aminolithium into the polymerizer is essential. The amount of lithium in the initiator solution containing aminolithium depends on the amount of impurities resulting in deactivation, but is preferably 0.05 to 3 mmol per 1 mol of the total monomer to be polymerized, preferably 0.1. ~ 1.5 mmol is more preferred. The amount of lithium in the initiator is related to the number average molecular weight of the target modified diene polymer. When trying to increase the number average molecular weight, reduce the amount of lithium in the initiator, and conversely try to decrease the number average molecular weight. If so, perform an operation to increase the amount of lithium in the initiator. Usually, the operation of increasing or decreasing the amount of lithium in the initiator is preferably performed while keeping the feed ratio of the organolithium and the secondary amine constant. The amount of lithium can be calculated from the amount of organic lithium and secondary amine charged.

<Polymerization process>
The polymerization monomer used in the polymerization step in the present embodiment contains 50 to 100 parts of a conjugated diene monomer and 50 to 0 parts of a copolymerizable monomer. That is, the polymerization in the present embodiment may be either homopolymerization of the conjugated diene monomer or copolymerization of the conjugated diene monomer and one or more kinds of monomers copolymerizable therewith. Each of the above-mentioned contents is shown as a supply ratio of the polymerization monomer used in the continuous production method of the modified diene polymer according to the present embodiment.

Specific examples of the conjugated diene monomer used in the present embodiment are not limited to the following, but are limited to 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, and 3 -Methyl-1,3-pentadiene, 1,3-heptadiene, 1,3-hexadiene and the like can be mentioned, and one kind or a combination of two or more kinds is used. Preferred examples of the conjugated diene monomer used in the present embodiment include 1,3-butadiene and isoprene.

The copolymerizable monomer used in the present embodiment includes various vinyl compounds, and is not particularly limited, and examples thereof include aromatic vinyl compounds and vinylsilane compounds. Examples of aromatic vinyl compounds include, but are not limited to, styrene, p-methylstyrene, α-methylstyrene, vinylethylbenzene, vinylxylene, vinylnaphthalene, diphenylethylene, 3- (2-dimethylaminoethyl) styrene, Examples thereof include (dimethylamino) dimethyl-4-vinylphenylsilane, and one or a combination of two or more thereof is used. Styrene is a preferred example of the aromatic vinyl compound used in the present embodiment. Further, in order to prevent cold flow of the conjugated diene polymer, a polyfunctional aromatic vinyl compound such as divinylbenzene can be used from the viewpoint of controlling branching. The vinylsilane compound is not limited to, for example, (dimethylamino) dimethylvinylsilane, (diethylamino) diethylvinylsilane, bis (dimethylamino) methylvinylsilane, bis (diethylamino) methylvinylsilane, bis (diethylamino) ethylvinylsilane, tris ( Dimethylamino) vinylsilane and the like can be mentioned.

In the present embodiment, a step of continuously introducing the polymerization monomer into the polymerizer is indispensable. The polymerization monomer is continuously put into the polymerizer together with the inert organic solvent, as a solution of the inert organic solvent, or with the solution of the inert organic solvent of the polymerization monomer and the remaining inert organic solvent. Introduce. The inert organic solvent in the polymerization step of the present embodiment is not particularly limited, and for example, the same as the inert organic solvent in the preparation step can be used.

In the present embodiment, the concentration of the polymerization monomer is preferably 5% by mass to 50% by mass, more preferably 8% by mass to 30% by mass. The concentration of the monomer for polymerization serves as a means for adjusting the temperature rise due to the heat of polymerization. In order to bring the temperature of the outlet of the polymer that discharges the polymer to the desired temperature, the temperature of the monomer for polymerization and the solvent, that is, the temperature of the inlet of the polymer that introduces the monomer for polymerization and the temperature rise due to the heat of polymerization It can be controlled by heat removal / heating means such as temperature and jacket. In order to lower the outlet temperature of the polymer, a method of lowering the inlet temperature, a method of lowering the concentration of the monomer for polymerization to reduce the temperature rise due to the heat of polymerization, a method of removing heat with a jacket or the like, heat of vaporization of the solvent There is a method of using the above, and these methods can be combined. On the other hand, to raise the outlet temperature, the reverse method is performed. As a means of removing heat and heating with a jacket or the like, there are a method of using a jacket and a method of using a coil / piping.

In the present embodiment, the temperature at the outlet of the polymer that discharges the polymer is preferably 40 ° C to 100 ° C, more preferably 45 ° C to 85 ° C. Within this range, a modified diene polymer having an amino group at the starting position tends to be obtained in a higher yield.

The polymerizer in this embodiment is preferably a polymerization reaction tank having a rotary stirrer. The polymerizer can be used alone or by connecting two or more in series with a pipe. The average residence time of the polymerizer is preferably 10 minutes to 4 hours, more preferably 20 minutes to 2 hours.

In the present embodiment, the step of continuously discharging the polymer solution from the polymerizer is included.

In the present embodiment, when two or more kinds of monomers are used, a random copolymer, a tapered random copolymer, a block copolymer or a copolymer having an intermediate structure thereof can be obtained.
A random copolymer is preferable for the purpose of obtaining a vulcanized rubber composition aimed at low hysteresis loss.

Generally, as a method of using monomers having different reactivity ratios as a random copolymer, a method of adding a specific polar compound as a randomizer, or as the polymerization progresses, the residual monomer ratio changes. , An increment method or a combined method thereof is adopted in which the monomer that reacts first is additionally fed during the polymerization.

In this embodiment, a randomizer is preferably used. The randomizer referred to here refers to controlling the microstructure of the conjugated diene polymer, for example, increasing the amount of 1,2 bonds of the butadiene part of the butadiene polymer or the butadiene-styrene polymer, 3,4 bonds of the isoprene polymer, etc. , And, it is a compound having an action of controlling the composition distribution of the monomer unit of the conjugated diene-vinyl aromatic hydrocarbon copolymer, for example, randomizing the butadiene unit and the styrene unit of the butadiene-styrene copolymer. In the present embodiment, the randomizer is not particularly limited, but includes all commonly used ones. Typical examples of the randomizer used are as follows.
(1) Ethers (2) Ortodimethoxybenzenes (3) Complex of alkali metal and ketone or phosphite triester (4) Compound R (OM ¹ ) _n , (RO) ₂ represented by the following general formula M ² , R (COOM ¹ ) _n , ROCOOM ¹ , RSO ₃ M ¹ , ROSO ₃ M ¹
(Here, R is selected from each of the aliphatic, alicyclic and aromatic hydrocarbon groups, M ¹ is an alkali metal, and in particular, represents lithium, sodium, potassium, rubidium or cesium, and M ² is an alkaline earth metal, specifically represents calcium or barium, and n is an integer of 1 to 3).
(5) Tertiary amine (6) Tertiary amine having an ether bond Hereinafter, the randomizer will be specifically described, but these randomizers can be used alone or in combination. Good.

(1) Specific examples of ethers are not limited to the following, but 1,2-dimethoxyethane, 1,2-diethoxyethane, tetrahydrofuran, 2-methoxymethyltetrahydrofuran, diethyl ether, triethylene glycol dimethyl ether, 2, Examples thereof include 2-bis (2-oxolanyl) propane.
(2) Specific examples of orthodimethoxybenzenes include, but are not limited to, veratrol, isohomo veratrol and the like.
(3) Specific examples of the complex of the alkali metal and the ketone or phosphite triester are not limited to the following, but are not limited to acetone, methyl ethyl ketone, diisopropyl ketone, benzophenone, acetophenone, dibenzyl ketone, fluorenone, xanthone, Michler ketone, and acetyl acetone. Such as ketones such as triethylphosphite, trioctylphosphite, tribenzylphosphite, trinonylphosphite, and a complex of lithium, sodium, potassium, rubidium, or cesium. Be done.

In (4), the randomizer represented by the general formula will be described.
Specific examples of alcohols, phenolic alkali metal salts or alkaline earth metal salts represented by the general formula R (OM ¹ ) _n or (RO) ₂ M ² are, but are not limited to, methyl alcohols and ethyl alcohols. , Isopropyl alcohol, tert-butyl alcohol, tert-amyl alcohol, cyclohexyl alcohol, allyl alcohol, 2-butenyl alcohol, benzyl alcohol, phenol, catechol, resorcinol, hydroquinone, 1-naphthyl alcohol, p-nonylphenol, lithium such as pyrogallol. , Sodium, potassium, rubidium, cesium, calcium and barium salts. Preferred are tert-amylalkoxy sodium and p-nonylphenoxy sodium.

Specific examples of the carboxylic acid and acidic carbonate of the alkali metal represented by the general formula R (COOM ¹ ) _n or ROCOOM ¹ are not limited to the following, but are, but not limited to, isovaleric acid, lauric acid, palmitic acid, stearic acid, and olein. Examples thereof include lithium, sodium, potassium, rubidium and cesium salts such as acid, logonic acid, benzoic acid, pimeric acid, acidic n-dodecyl carbonate and acidic phenyl carbonate.

Specific examples of the alkali metal sulfonic acid and sulfate ester salt represented by the general formula RSO ₃ M ¹ or ROSO ₃ M ¹ are not limited to the following, but dodecylbenzene sulfonic acid, diisopropylnaphthalinsulfonic acid, N-methyl- Includes lithium, sodium, potassium, rubidium and cesium salts such as N-methanesulfonate laurylamide, lauryl alcohol sulfate, caproyl ethylene glycol sulfate and the like.

(5) Specific examples of the tertiary amine include, but are not limited to, triethylamine, tetramethylethylenediamine and the like.

(6) Specific examples of the tertiary amine having an ether bond include, but are not limited to, bis (2-dimethylaminoethyl) ether and bis [2- (1-piperidyl) ethyl] ether.

Among the above, preferred randomizers include (1) ethers and (5) tertiary amines.

The amount of the randomizer used is preferably in the range of 0.01 to 1000 molar equivalents per molar equivalent of the organolithium compound.

In the present embodiment, the inclusion method is also preferably used as the randomization method. Hereinafter, the increment method will be specifically described. Two or more kinds of monomers are fed together with the polymerization initiator to the first reaction band of the polymer, and the second reaction band or, if necessary, the third reaction. This is a method of additionally feeding a monomer having a high reactivity ratio to the band. The additional feed is called an inclusion feed. Here, the initiation reaction stage of polymerization is referred to as a first reaction zone, and thereafter, the growth reaction stage is referred to as a second and third reaction zones. The monomer having a high reactivity ratio preferably feeds 50% by mass to 95% by mass of the whole to the first reaction band, and adds the remaining 50% by mass to 5% by mass after the second reaction band. As the monomer to be additionally fed, a monomer having a high reactivity ratio may be mixed with a monomer having a lower reactivity ratio.

Specifically, in the case of producing a butadiene-styrene random copolymer, for example, in two-unit continuous polymerization, 80% by mass of the total butadiene monomer is added to the bottom of the first polymerizer together with an initiator and a solvent. And 100% by mass of styrene, 10% by mass of the whole butadiene monomer is fed to the upper part of the first polymerizer, and 10% of the whole butadiene monomer is fed to the bottom of the second polymerizer together with the polymerization reaction solution. A method of feeding% by mass can be mentioned.

When the modified diene-based polymer obtained in the present embodiment is a modified random copolymer, the composition of the monomer in the copolymer of the monomer having a high reactivity ratio and the monomer having a low reactivity ratio is different. , It is preferable that they are randomly distributed, but if they are non-uniform, a chain structure in which monomers having a low reactivity ratio are connected may be formed. As a method for analyzing the chain structure, in the case of a copolymer of butadiene and styrene, Kolthoff's method (method described in IMKOLTHOFF. Et al., J. Polym. Sci. 1,429 (1946)). A known method is used in which the polymer is decomposed by the above method and the polystyrene portion having a chain of 30 or more aromatic vinyl units unnecessary for methanol is quantitatively analyzed. The polystyrene portion having a chain of 30 or more aromatic vinyl units is preferably 5% by mass or less, more preferably 3% by mass or less, based on the total amount of the polymer.

In the present embodiment, the initiator solution, the monomer for polymerization and the solvent are continuously fed to the polymerizer. Various methods can be selected as the feed method. Not limited to the following, for example, a method of feeding an initiator solution containing aminolithium and a polymerization monomer or a solution and solvent of the polymerization monomer from separate inlets to a polymerizer, including aminolithium. A method of feeding an initiator solution and a polymerization monomer or a solution of a polymerization monomer and a solvent to a polymerizer from another inlet, a method of feeding an initiator solution containing aminolithium and a part of a solvent into one inlet. From the method of feeding the polymerization monomer or the solution of the polymerization monomer and the remaining solvent from another inlet, the initiator solution containing aminolithium and at least one of the polymerization monomers are mixed. A feeding method, an initiator solution containing aminolithium, a polymerization monomer or a polymerization monomer solution and a solvent are mixed in advance and fed from one inlet, and the like can be selected. Of these, a method of feeding the initiator solution containing aminolithium and a part of the solvent from one inlet, and the polymerization monomer or the solution of the polymerization monomer and the remaining solvent from the other inlet. More preferred. In this case, side reactions are less likely to occur, and the polymerization step tends to be more stable.

In the present embodiment, a step of inactivating an impurity contained in the polymerization monomer or a solution of the polymerization monomer by mixing an organic metal compound, and after inactivation. It is preferable to further include a step of introducing the polymerization monomer or the solution of the polymerization monomer into the polymerizer. More preferably, the organometallic compound does not contain aminolithium. When aminolithium is contained as an organic metal, a secondary amine is generated after reacting with an impurity, which tends to cause a side reaction including chain transfer in the polymerization step.

Examples of impurities contained in the polymerization monomer are not particularly limited, but are trace amounts of water, acetylenes, 1,2-diene compounds, phenol compounds as polymerization inhibitors, and the like. The monomer for polymerization is any one of a conjugated diene monomer, another copolymerizable monomer, or all the monomers or at least a part thereof. The acetylenes are not particularly limited, and examples thereof include vinylacetylene, methylacetylene, and phenylacetylene, and the 1,2-diene compound is not particularly limited, and examples thereof include 1,2-butadiene and propadiene. ..

The organometallic compound is not particularly limited, but a compound having a carbon-metal bond of an organic group, being soluble in a solvent, and having a small effect on subsequent polymerization is preferable. The metal is not particularly limited, but Group 1, Group 2, and Group 13 are preferable, and specific examples thereof include, but are not limited to, alkali metals, alkaline earth metals, and aluminum. Specific examples of the organometallic compound are not limited to the following, but are limited to alkyllithium such as n-butyllithium and sec-butyllithium, dialkylmagnesium such as dibutylmagnesium and butylethylmagnesium, and trialkyl such as triethylaluminum and diethylisopropylaluminum. Aluminum is mentioned. More preferable organometallic compounds are n-butyllithium and sec-butyllithium.

The method of mixing an organic metal compound with the above-mentioned polymerization monomer and feeding it has the effect of reducing the influence of impurities in the monomer, thereby contributing to the stabilization of the polymerization process and suppressing the fluctuation of the molecular weight.

Regarding the amount of the organometallic compound added, it is preferable to measure the amount of impurities in the polymerization monomer to be used in advance and add the corresponding amount in just proportion. That is, the amount of the organometallic compound added can be appropriately adjusted depending on the amount of impurities in the polymerization monomer used, but is preferably 0.01 to 1 mmol per mole of the polymerization monomer.

In the present embodiment, various known methods can be used for mixing the initiator solution with the solvent or the like, or mixing the polymerization monomer or the solution of the polymerization monomer with the organometallic compound, but it is preferable. It is a method of continuously mixing, and for example, a mixing means such as connecting pipes, a static mixer, and a venturi pipe can be used. It is preferable that the temperature is sufficiently low so that the polymerization monomer does not start the polymerization reaction and the average residence time is short by the inlet of the polymerizer. The temperature inside the polymer inlet pipe is preferably 40 ° C. or lower, more preferably 30 ° C. or lower. The average residence time to the inlet of the polymer after mixing is preferably 10 minutes or less, more preferably 5 minutes or less.

In the preparation step of the present embodiment, at least one kind of polymerization monomer can be present in the reactor when the organolithium and the secondary amine are continuously reacted. In that case, the impurities in the polymerization monomer react with the organic lithium at an early stage, and an initiator solution containing aminolithium can be obtained in a high yield, which is further effective in stabilizing the polymerization process.

<Degeneration process>
In the step of continuously discharging the polymer solution from the polymer in the present embodiment, it is preferable to further include a step of continuously adding a terminal modifier to the polymer solution, and more preferably, the terminal modifier is added to the polymer solution. Further includes a modification step of continuously adding the solvent, and a step of removing the solvent from the polymer solution that has undergone the modification step. By the step of continuously adding the terminal modifier, a modified diene polymer having a modified terminal terminal can be obtained. The terminal denaturing agent is not particularly limited, but when a monofunctional compound is used, a linear double-ended diene polymer is obtained, and when a polyfunctional compound is used, a branched double-ended diene polymer is obtained. A polymer is obtained. Preferably, a monofunctional or polyfunctional compound containing at least one element selected from the group consisting of nitrogen, silicon, tin, phosphorus, oxygen, sulfur and halogen is used as the terminal modifier. In addition, an onium structure can be introduced into the modified conjugated diene-based polymer by adding a terminal modifier containing an onium-producing agent and reacting. Further, a terminal modifier containing a plurality of functional groups containing these elements in the molecule, or a terminal modifier containing a functional group containing a plurality of these elements can also be used. By the step of continuously adding these terminal modifiers, a vulcanized rubber composition aimed at lower hysteresis loss tends to be obtained.

(Various terminal denaturants)
The nitrogen-containing compound as the terminal modifier is not limited to the following, and includes, for example, isocyanato compound, isothiocyanate compound, isocyanuric acid derivative, nitrogen group-containing carbonyl compound, nitrogen group-containing vinyl compound, nitrogen group-containing epoxy compound and the like. Can be mentioned.

Examples of the silicon-containing compound as the terminal modifier include, but are not limited to, a silicon halide compound, an epoxidized silicon compound, a vinylized silicon compound, an alkoxy silicon compound, and an alkoxy silicon compound containing a nitrogen-containing group. ..

The tin-containing compound as the terminal modifier is not limited to the following, and examples thereof include tin halide compounds and organotin carboxylate compounds.

The phosphorus-containing compound as the terminal denaturing agent is not limited to the following, and examples thereof include phosphite ester compounds and phosphino compounds.

The oxygen-containing compound as the terminal modifier is not limited to the following, and examples thereof include epoxy compounds, ether compounds, and ester compounds.

The sulfur-containing compound as the terminal modifier is not limited to the following, and examples thereof include a mercapto group derivative, a thiocarbonyl compound, and isothiocyanate.

The halogen-containing compound as the terminal modifier is not limited to the following, and examples thereof include the above-mentioned silicon halide compound and tin halogenated compound.

The onium-producing agent as the terminal modifier is not limited to the following, and includes, for example, a protected amine compound (producing ammonium) capable of forming a primary or secondary amine, and a protected phosphine capable of forming a hydrophosphine. Examples include compounds (which produce phosphonium), hydroxyl groups, and compounds which can form thiols (which produce oxonium and sulfonium), and each molecule has a functional group for binding the onium-producing agent and the modified conjugated diene-based polymer. It is preferable to use the terminal modifier contained therein. The functional group for binding the modified conjugated diene polymer is not limited to the following, but for example, an unsaturated group such as a carbonyl group (ketone, ester, etc.), a vinyl group, an epoxy group, a silicon halide group, etc. Examples thereof include an alkoxysilicon group.

Specific examples of the terminal modifier include, but are not limited to, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, diphenylmethane diisocyanate, and polypeptide type diphenylmethane diisocyanate as isocyanate compounds. (C-MDI), phenylisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, butyl isocyanate, 1,3,5-benzenetriisocyanate and the like can be mentioned. Further, the isocyanuric acid derivative is not limited to, for example, 1,3,5-tris (3-trimethoxysilylpropyl) isocyanurate, 1,3,5-tris (3-triethoxysilylpropyl) isocyanurate. , 1,3,5-tri (oxylan-2-yl) -1,3,5-triazinan-2,4,6-trione, 1,3,5-tris (isocyanatomethyl) -1,3,5 -Triazinan-2,4,6-trione, 1,3,5-trivinyl-1,3,5-triazinan-2,4,6-trione, and the like.

Specific examples of the nitrogen group-containing carbonyl compound as a terminal modifier include, but are not limited to, 1,3-dimethyl-2-imidazolidinone, 1-methyl-3-ethyl-2-imidazolidinone, 1-. Methyl-3- (2-methoxyethyl) -2-imidazolidinone, N-methyl-2-pyrrolidone, N-methyl-2-piperidone, N-methyl-2-quinolone, 4,4'-bis (diethylamino) Benzophenone, 4,4'-bis (dimethylamino) benzophenone, methyl-2-pyridyl ketone, methyl-4-pyridyl ketone, propyl-2-pyridyl ketone, di-4-pyridyl ketone, 2-benzoylpyridine, N, N , N', N'-tetramethylurea, N, N-dimethyl-N', N'-diphenylurea, N, N-diethylcarbamate methyl, N, N-diethylacetamide, N, N-dimethyl-N' , N'-dimethylaminoacetamide, N, N-dimethylpicolinic acid amide, N, N-dimethylisonicotinic acid amide and the like.

Specific examples of the nitrogen group-containing vinyl compound as a terminal modifier are not limited to the following, but are not limited to N, N-dimethylacrylamide, N, N-dimethylmethacrylate, N-methylmaleimide, N-methylphthalimide, N, N. -Bistrimethylsilylacrylamide, morpholinoacrylamide, 3- (2-dimethylaminoethyl) styrene, (dimethylamino) dimethyl-4-vinylphenylsilane, 4,4'-vinylidenebis (N, N-dimethylaniline), 4,4 ′ -Binilidenebis (N, N-diethylaniline), 1,1-bis (4-morpholinophenyl) ethylene, 1-phenyl-1- (4-N, N-dimethylaminophenyl) ethylene and the like can be mentioned.

Specific examples of the nitrogen group-containing epoxy compound as a terminal modifier are not limited to the following, but are not limited to N, N, N', N'-tetraglycidyl-1,3-bisaminomethylcyclohexane, N, N, N'. , N'-tetraglycidyl-m-xylene diamine, 4,4-methylene-bis (N, N-diglycidylaniline), 1,4-bis (N, N-diglycidylamino) cyclohexane, N, N, N ', N'-Tetraglycidyl-p-phenylenediamine, 4,4'-bis (diglycidylamino) benzophenone, 4- (4-glycidylpiperazinyl)-(N, N-diglycidyl) aniline, 2- [2 -(N, N-diglycidylamino) ethyl] -1-glycidylpyrrolidin, bis (glycidylmethylaniline), N, N'-diglycidyl-4-glycidyloxyaniline, 4,4'-diglycidyl-diphenylmethylamine, 4 , 4'-Diglycidyl-dibenzylmethylamine, N, N-diglycidylaniline, N, N-diglycidyl orthotoluidine, N, N-diglycidylaminomethylcyclohexane and the like.

Specific examples of the silicon halide compound as the terminal modifier include, but are not limited to, dibutyldichlorosilane, methyltrichlorosilane, dimethyldichlorosilane, methyldichlorosilane, trimethylchlorosilane, tetrachlorosilane, tris (trimethylsiloxy) chlorosilane, and the like. Tris (dimethylamino) chlorosilane, hexachlorodisilane, bis (trichlorosilyl) methane, 1,2-bis (trichlorosilyl) ethane, 1,2-bis (methyldichlorosilyl) ethane, 1,4-bis (trichlorosilyl) butane , 1,4 bis (methyldichlorosilyl) butane and the like.

Specific examples of the silicon epoxidized compound as the terminal modifier are not limited to the following, but are limited to 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, and 3-glycidoxypropylmethyldiethoxy. Examples thereof include silane and epoxy-modified silicone.

Specific examples of the alkoxysilicon compound as the terminal modifier include, but are not limited to, tetramethoxysilane, tetraethoxysilane, triphenoxymethylsilane, methoxy-substituted polyorganosiloxane, and the like.

Specific examples of the alkoxysilicon compound containing a nitrogen-containing group as a terminal modifier include, but are not limited to, 3-dimethylaminopropyltrimethoxysilane, 3-dimethylaminopropylmethyldimethoxysilane, and 3-diethylaminopropyltriethoxysilane. , 3-Molholinopropyltrimethoxysilane, 3-piperidinopropyltriethoxysilane, 3-hexamethyleneiminopropylmethyldiethoxysilane, 3- (4-methyl-1-piperazino) propyltriethoxysilane, 1- [3 -(Triethoxysilyl) -propyl] -3-methylhexahydropyrimidine, 3- (4-trimethylsilyl-1-piperazino) propyltriethoxysilane, 3- (3-triethylsilyl-1-imidazolidinyl) propylmethyldiethoxysilane , 3- (3-trimethylsilyl-1-hexahydropyrimidinyl) propyltrimethoxysilane, 3-dimethylamino-2- (dimethylaminomethyl) propyltrimethoxysilane, bis (3-dimethoxymethylsilylpropyl) -N-methylamine , Bis (3-trimethoxysilylpropyl) -N-methylamine, Bis (3-triethoxysilylpropyl) methylamine, Tris (trimethoxysilyl) amine, Tris (3-trimethoxysilylpropyl) amine, N, N , N', N'-tetra (3-trimethoxysilylpropyl) ethylenediamine, 3-isocyanatopropyltrimethoxysilane, 3-cyanopropyltrimethoxysilane, 2,2-dimethoxy-1- (3-trimethoxysilylpropyl) ) -1-aza-2-silacyclopentane, 2,2-diethoxy-1- (3-triethoxysilylpropyl) -1-aza-2-silacyclopentane, 2,2-dimethoxy-1- (4-) Trimethoxysilylbutyl) -1-aza-2-silacyclohexane, 2,2-dimethoxy-1- (3-dimethoxymethylsilylpropyl) -1-aza-2-silacyclopentane, 2,2-dimethoxy-1- Phenyl-1-aza-2-silacyclopentane, 2,2-diethoxy-1-butyl-1-aza-2-silacyclopentane, 2,2-dimethoxy-1-methyl-1-aza-2-silacyclo Pentan, 2,2-dimethoxy-8- (4-methylpiperazinyl) methyl-1,6-dioxa-2-silacyclooctane, 2,2-dimethoxy-8- (N, N-diethylamino) methyl-1 , 6-Geo Examples thereof include xa-2-silacyclooctane.

Specific examples of a compound having an unsaturated bond and a protected amine in the molecule as a protected amine compound capable of forming a primary or secondary amine as a terminal modifier include, but are not limited to, 4,4'. -Vinylidenevis [N, N-bis (trimethylsilyl) aniline], 4,4'-Binilidenbis [N, N-bis (triethylsilyl) aniline], 4,4'-Binylidenebis [N, N-bis (t) -Butyldimethylsilyl) aniline], 4,4'-vinylidenebis [N-methyl-N- (trimethylsilyl) aniline], 4,4'-vinylidenebis [N-ethyl-N- (trimethylsilyl) aniline], 4, 4'-Binilidenbis [N-methyl-N- (triethylsilyl) aniline], 4,4'-Biniridenbis [N-ethyl-N- (triethylsilyl) aniline], 4,4'-Binilidenbis [N- Methyl-N- (t-butyldimethylsilyl) aniline], 4,4'-vinylidenebis [N-ethyl-N- (t-butyldimethylsilyl) aniline], 1- [4-N, N-bis (trimethylsilyl) ) Aminophenyl] -1- [4-N-methyl-N- (trimethylsilyl) aminophenyl] ethylene, 1- [4-N, N-bis (trimethylsilyl) aminophenyl] -1- [4-N, N- Dimethylaminophenyl] ethylene and the like can be mentioned. Specific examples of the protected amine compound capable of forming a primary or secondary amine and a compound having an alkoxysilane and a protected amine in the molecule are not limited to the following, but N, N-bis (trimethylsilyl) aminopropyl. Trimethoxysilane, N, N-bis (trimethylsilyl) aminopropylmethyldimethoxysilane, N, N-bis (trimethylsilyl) aminopropyltriethoxysilane, N, N-bis (trimethylsilyl) aminopropylmethyldiethoxysilane, N, N -Bis (trimethylsilyl) aminoethyltrimethoxysilane, N, N-bis (trimethylsilyl) aminoethylmethyldiethoxysilane, N, N-bis (triethylsilyl) aminopropylmethyldiethoxysilane, 3- (4-trimethylsilyl-1) -Piperadino) propyltriethoxysilane, 3- (3-triethylsilyl-1-imidazolidinyl) propylmethyldiethoxysilane, 3- (3-trimethylsilyl-1-hexahydropyrimidinyl) propyltrimethoxysilane, 2,2-dimethoxy- 1- (3-Trimethoxysilylpropyl) -1-aza-2-silacyclopentane, 2,2-diethoxy-1- (3-triethoxysilylpropyl) -1-aza-2-silacyclopentane, 2, 2-Dimethoxy-1- (4-trimethoxysilylbutyl) -1-aza-2-silacyclohexane, 2,2-dimethoxy-1- (3-dimethoxymethylsilylpropyl) -1-aza-2-silacyclopentane , 2,2-Dimethoxy-1-phenyl-1-aza-2-silacyclopentane, 2,2-diethoxy-1-butyl-1-aza-2-silacyclopentane, 2,2-dimethoxy-1-methyl -1-aza-2-silacyclopentane and the like can be mentioned.

Specific examples of the tin halide compound include, but are not limited to, tetrachlorotin, tetrabromstin, trichlorobutyltin, trichlorooctyltin, dibromdimethyltin, dichlorodibutyltin, chlorotributyltin, chlorotrioctyltin, and chlorotriphenyl. Tin, 1,2-bis (trichlorostanyl) ethane, 1,2-bis (methyldichlorostanyl) ethane, 1,4-bis (trichlorostanyl) butane, 1,4 bis (methyldichlorostanyl) butane And so on.

Specific examples of the organotin carboxylate compound include, but are not limited to, ethyl tin tristearate, butyl tin trioctanoate, butyl tin tristearate, butyl tin trilaurate, dibutyl tin bisoctanoate and the like.

Specific examples of the phosphite ester compound include, but are not limited to, trimethyl phosphate, tributyl phosphate, triphenyloxide phosphite and the like.

Specific examples of the phosphino compound include, but are not limited to, protected phosphino such as P, P-bis (trimethylsilyl) phosphinopropyltrimethoxycisilane and P, P-bis (triethylsilyl) phosphinopropylmethylethoxysilane. Examples thereof include compounds, 3-dimethylphosphinopropyltrimethoxycisilane, 3-diphenylphosphinopropyltrimethoxycisilane and the like.

Specific examples of the oxygen-containing compound include, but are not limited to, polyglycidyl ethers such as ethylene glycol diglycidyl ether and glycerin triglycidyl ether, 1,4-diglycidyl benzene, 1,3,5-triglycidyl benzene, and polyepoxy. Examples thereof include polyepoxy compounds such as liquefied polybutadiene, epoxidized soybean oil, and epoxidized flaxseed oil, and ester compounds such as dimethyl adipate, diethyl adipate, dimethyl terephthalate, and diethyl terephthalate, which have a hydroxyl group at the polymer terminal. Generate.

Specific examples of the sulfur-containing compound include, but are not limited to, protected thiol compounds such as S-trimethylsilylthiopropyltrimethoxycisilane and S-triethylsilylthiopropylmethyldiethylsilane, S-methylthiopropyltrimethoxycisilane, and S. -Ethylthiopropylmethyldiethoxysisilane, ethyl N, N-diethyldithiocarbamate, phenylisothiocyanate, phenyl-1,4-diisothiocyanate, hexamethylenediisothiocianate, butylisothiocianate and the like can be mentioned. ..

In the present embodiment, a polymerization inhibitor such as water or alcohol, an antioxidant such as phenol-based, phosphorus-based or sulfur-based, a neutralizing color inhibitor such as boric acid or carboxylic acid, and a spreading oil are added to the polymer solution. be able to.

The antioxidant is not particularly limited, and known ones are used. For example, 2,6-di-tert-butyl-4-hydroxytoluene (BHT) and n-octadecyl-3- (4'-hydroxy) are used. -3', 5'-di-tert-butylphenol) propionate, 2-methyl-4,6-bis [(octylthio) methyl] phenol and the like are preferable.

In the present embodiment, in order to improve the processability of the modified diene polymer, extender oil can be added to the modified diene polymer as needed. The method of adding the extension oil to the modified diene polymer is not particularly limited, but a method of adding the extension oil to the polymer solution, mixing the mixture, and then removing the solvent is preferable to obtain the oil extension modified diene polymer. .. The extension oil is not limited to the following, and examples thereof include aroma oil, naphthenic oil, and paraffin oil. Among these, an aroma substitute oil having a polycyclic aromatic (PCA) component of 3% by mass or less according to the IP346 method is preferable from the viewpoint of environmental safety, prevention of oil bleeding, and wet grip characteristics. The aroma substitute oil is not limited to the following, and is, for example, TDAE (Treated Distilate Aromatic Extracts), MES (Milde Extract, etc.), MES (Mild Extract), etc. Extracts) and the like. The amount of the spreading oil added is not particularly limited, but is usually 0 to 60 parts by mass, preferably 5 to 55 parts by mass with respect to 100 parts by mass of the modified diene polymer.

In the present embodiment, the method for removing the solvent from the polymer solution is not particularly limited, and known means can be used. Although not limited to the following, for example, a method of removing the solvent by steam stripping, dehydration and drying, a method of concentrating in a flash tank and further devolatile with a vent extruder or the like, direct volatilization with a vent extruder or a drum dryer or the like. A method or the like is used.

In the present embodiment, the obtained modified diene polymer preferably has a weight average molecular weight of 50,000 to 2 million, and the non-oil-extended polymer has a Mooney viscosity at 110 ° C. of 30 to 150. preferable. In the case of an oil-extended polymer, it is more preferable that the Mooney viscosity at 100 ° C. is 20 to 100. The weight average molecular weight and the Mooney viscosity can be measured by the methods described in Examples described later, respectively.

The amount of the bound conjugated diene in the conjugated diene-based polymer obtained in the present embodiment is not particularly limited, but is preferably 50 to 100% by mass, more preferably 60 to 80% by mass. The amount of bound aromatic vinyl in the conjugated diene polymer obtained in the present embodiment is not particularly limited, but is preferably 0 to 50% by mass, more preferably 20 to 40% by mass. When the amount of the bonded conjugated diene and the amount of the bonded aromatic vinyl are in the above ranges, a vulcanized product having a better balance between fuel saving and wet grip tends to be obtained. Here, the amount of bound aromatic vinyl can be measured by the ultraviolet absorption of the phenyl group, and the amount of bound conjugated diene can also be determined from this value. Specifically, it can be measured by a method according to an example described later.

The amount of vinyl bonded to the conjugated diene polymer obtained in the present embodiment is not particularly limited, but is preferably 10 to 75 mol%, more preferably 25 to 65 mol%. When the vinyl bond amount is in the above range, a vulcanized product having a better balance between fuel efficiency and wet grip tends to be obtained. Here, when the modified conjugated diene-based polymer is a copolymer of butadiene and styrene, the butadiene bond unit is contained by the Hampton method (RR Hampton, Analytical Chemistry, 21,923 (1949)). The vinyl bond amount (1,2-bond amount) can be determined.
Fuel saving performance when the microstructure (the amount of each bond in the modified conjugated diene polymer) is in the above range and the glass transition temperature of the modified conjugated diene polymer is in the range of 45 to -15 ° C. There is a tendency to obtain a more excellent vulcanized product due to the balance between the wet grip property and the wet grip property. Regarding the glass transition temperature, according to ISO22768: 2006, the DSC curve is recorded while raising the temperature in a predetermined temperature range, and the peak top (Inflection point) of the DSC differential curve is defined as the glass transition temperature.

The polystyrene-equivalent number average molecular weight (Mn) of the modified conjugated diene polymer obtained in the present embodiment obtained by gel permeation chromatography (GPC) is preferably 20,000 to 2,000,000, more preferably 20,000 to 2,000,000. It is 100,000 to 1,000,000, more preferably 150,000 to 800,000, and even more preferably 200,000 to 600,000. By setting the molecular weight to be equal to or higher than the above lower limit value, the strength of the vulcanized product tends to be further improved, and by setting the molecular weight to be lower than the above upper limit value, the processability tends to be further improved. The ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is preferably 1.05 to 3.0, more preferably 1.1 to 3.0 from the viewpoint of physical properties of the vulcanized product. It is 2.5.

<Composition of modified rubbery polymer>
In the present embodiment, the obtained modified diene-based polymer can be a composition in which another rubber-like polymer is blended, if necessary, and a reinforcing filler is blended. Further, a cross-linking agent can be added to obtain a vulcanized rubber composition.

The other rubber-like polymer is a rubber-like polymer other than the modified rubber-like polymer obtained in the present embodiment. Such a rubber-like polymer is not particularly limited, and examples thereof include non-diene rubber-like polymers such as EP rubber and butyl rubber, in addition to polybutadiene, SBR, natural rubber, and synthetic polyisoprene.

The reinforcing filler is not limited to the following, and examples thereof include silica-based inorganic fillers and carbon black. Examples of the silica-based filler include, but are not limited to, inorganic fibrous substances such as silica, clay, talc, mica, diatomaceous earth, wollastonite, montmorillonite, zeolite, and glass fiber. Examples of silica include, but are not limited to, wet silica, dry silica, and synthetic silicate silica. Among these, wet silica has an excellent balance of performance and is preferably used. Nitrogen adsorption specific surface area determined by the BET adsorption method of the silica-based inorganic filler is preferably 100 to 300 m ² / g, more preferably 170~250m ² / g. If necessary, a silica-based inorganic filler having a relatively small specific surface area (for example, a specific surface area of 200 m ² / g or less) and a silica-based inorganic filler having a relatively large specific surface area (for example, a specific surface area of 200 m ² / g or more) are used. ) Can be used in combination with a silica-based inorganic filler. The blending amount of the silica-based inorganic filler in the composition of the modified conjugated diene-based polymer is 0.5 to 300 parts by mass with respect to 100 parts by mass of the rubber component containing the modified diene-based polymer obtained in the present embodiment. Is preferable.

The carbon black is not particularly limited, and for example, carbon black of each class such as SRF, FEF, HAF, ISAF, and SAF can be used. The blending amount of carbon black is preferably 0.5 to 100 parts by mass with respect to 100 parts by mass of the rubber component containing the modified diene polymer obtained in the present embodiment.

In the present embodiment, as the composition of the obtained modified diene polymer, a silane coupling agent, a softening agent for rubber, a vulcanizing agent, a vulcanization accelerator, and a vulcanization aid can be further added, and further necessary. This allows the addition of other softeners, liquid resins, other fillers, heat-resistant stabilizers, antistatic agents, weather-resistant stabilizers, anti-aging agents, colorants, and lubricants. These are not particularly limited, and various known ones can be used.

The silane coupling agent has a function of closely interacting with the rubber component and the silica-based inorganic filler, and generally has a sulfur bond or a thiol moiety and an alkoxysilyl group or silanol group moiety of 1. The compound contained in the molecule is used. Specifically, but not limited to the following, for example, bis- [3- (triethoxysilyl) -propyl] -tetrasulfide, bis- [3- (triethoxysilyl) -propyl] -disulfide, mercaptopropyltrimethoxy. Examples thereof include silane, Si363 manufactured by Ebonic Degussa, NXT-Z30, NXT-Z45 and NXT-Z60 manufactured by Momentive. The blending amount of the silane coupling agent is preferably 0.1 to 30 parts by mass with respect to 100 parts by mass of the above-mentioned silica-based inorganic filler.

The sulfide is not limited to the following, and for example, radical generators such as organic peroxides and azo compounds, oxime compounds, nitroso compounds, polyamine compounds, sulfur, and sulfur compounds can be used. The amount of the vulcanizing agent used is preferably 0.01 to 15 parts by mass with respect to 100 parts by mass of the rubber component. The vulcanization accelerator is not limited to the following, but is, for example, sulfenamide type, guanidine type, thiuram type, aldehyde-amine type, aldehyde-ammonia type, thiazol type, thiourea type, dicarbamate type. Is used. The amount of the vulcanization accelerator used is preferably 0.01 to 20 parts by mass with respect to 100 parts by mass of the rubber component. The vulcanization aid is not limited to the following, and for example, zinc oxide, stearic acid and the like can be used.

In the present embodiment, as a method for producing the composition of the obtained modified diene polymer, a method using various kneaders can be selected. For example, a melt-kneading method using an open roll, a Banbury mixer, a kneader, a single-screw screw extruder, a twin-screw screw extruder or the like is preferable. Generally, the vulcanization temperature is preferably 120 to 200 ° C.

Hereinafter, the present embodiment will be described in more detail with reference to examples, but the present embodiment is not limited to these examples as long as the gist of the present embodiment is not exceeded.
Various measurements were performed by the following methods.

[Average residence time]
The average residence time was calculated as a value obtained by dividing the reactor volume (volume excluding the volume of the stirring blade / element) by the sum of the average supply rate of the secondary amine and the average supply rate of the solvent. Specifically, the values of "supply amine (mL / min)" (average supply rate of piperidine alone) and "solvent (mL / min)" (solvent for dissolving n-butyllithium) shown in Table 1 And the value of (the average supply rate of the solvent merging with piperidine as a whole) was calculated.

[Residual amount of secondary amine (conversion rate)]
The reaction was stopped by adding an excess amount of tetramethoxysilane to lithium to the initiator solution containing aminolithium. Using the solution after the reaction was stopped as a sample, the amount of residual secondary amine was measured using a FID detector using a gas chromatography (GC) measuring device (trade name "GC7890A" manufactured by Agilent). The amount of secondary amine was quantified based on a calibration curve prepared from a sample having a known concentration, and the rate of decrease with respect to the amount charged was taken as the conversion rate. The column used was a trade name "CP7447" manufactured by Agilent, and other measurement conditions were as follows.
<Inlet condition>
Injection port temperature: 270 ° C
Injection method: Split method 30: 1
Injection volume: 3 μL
<Column condition>
Temperature rise conditions: Hold at 100 ° C. for 16 minutes, then heat up at 30 ° C./min, then hold at 250 ° C. for 4 minutes Column flow rate: 1.8 mL / min <Detector conditions>
Detector temperature: 300 ° C

(Physical Properties 1) Amount of Bonded Styrene Using a modified conjugated diene polymer as a sample, 100 mg of the sample was made up to 100 mL with chloroform and dissolved to prepare a measurement sample. The amount of bonded styrene (mass%) with respect to 100% by mass of the modified conjugated diene polymer as a sample was measured by the amount of ultraviolet absorption wavelength (around 254 nm) absorbed by the phenyl group of styrene (spectrum manufactured by Shimadzu Corporation). Photometric meter "UV-2450").

(Physical properties 2) Microstructure of butadiene part (1,2-vinyl bond amount)
Using the modified conjugated diene polymer as a sample, 50 mg of the sample was dissolved in 10 mL of carbon disulfide to prepare a measurement sample. Using a solution cell, the infrared spectrum was measured in the range of 600 to 1000 cm ^-1 , and the absorbance at a predetermined wave number was used by Hampton's method (method described in RR Hampton, Analytical Chemistry 21, 923 (1949)). The microstructure of the butadiene moiety, that is, the amount of 1,2-vinyl bond (mol%) was determined according to the above formula (Fourier transform infrared spectrophotometer "FT-IR230" manufactured by JASCO Corporation).

(Physical Properties 3) Molecular Weight A GPC measuring device (trade name "HLC-8320GPC" manufactured by Toso Co., Ltd.) in which three columns using a polystyrene gel as a filler are connected using a conjugated diene polymer or a modified conjugated diene polymer as a sample. ) Is used to measure the chromatogram using an RI detector (trade name "HLC8020" manufactured by Toso), and the weight average molecular weight (Mw) is calculated based on the calibration line obtained using standard polystyrene. Number average molecular weight (Mn) and molecular weight distribution (Mw / Mn), peak top molecular weight of modified conjugated diene polymer (Mp ₁ ), peak top molecular weight of conjugated diene polymer (Mp ₂ ) and their ratio (Mp ₁₎ / Mp ₂ ) and the ratio of molecular weight of 2 million or more and 5 million or less were determined. THF was used as the eluent. As the column, three Tosoh product names "TSKgel SuperMultipore HZ-H" were connected, and a Tosoh product name "TSKguardcolum SuperMP (HZ) -H" was connected and used as a guard column in front of the column. 10 mg of the sample for measurement was dissolved in 20 mL of THF to prepare a measurement solution, and 10 μL of the measurement solution was injected into a GPC measuring device and measured under the conditions of an oven temperature of 40 ° C. and a THF flow rate of 0.35 mL / min.

(Physical properties 4) Polymer Mooney viscosity Using a modified conjugated diene polymer as a sample, a Mooney viscosity meter (trade name "VR1132" manufactured by Ueshima Seisakusho Co., Ltd.) is used, and in accordance with JIS K6300, Mooney viscosity is used using an L-shaped rotor. Was measured. First, the sample was preheated at the test temperature for 1 minute, the rotor was rotated at 2 rpm, and the torque after 4 minutes was measured to obtain the Mooney viscosity (ML _{(1 + 4)} ).

(Physical properties 5) Modification rate By applying the property of adsorbing the modified basic polymer component to a GPC column using a conjugated diene polymer or a modified conjugated diene polymer as a sample and using a silica gel as a filler. ,It was measured. The amount of adsorption of the sample and the sample solution containing the low molecular weight internal standard polystyrene to the silica-based column was measured from the difference between the chromatogram measured on the polystyrene-based column and the chromatogram measured on the silica-based column, and the modification rate was determined. I asked. Specifically, it is as shown below.
Preparation of sample solution: 10 mg of sample and 5 mg of standard polystyrene were dissolved in 20 mL of THF to prepare a sample solution.
GPC measurement conditions using a polystyrene column: Using the trade name "HLC-8320 GPC" manufactured by Tosoh Corporation, using THF as an eluent, injecting 10 μL of the sample solution into the apparatus, column oven temperature 40 ° C., THF flow rate. Chromatograms were obtained using an RI detector under the condition of 0.35 mL / min. As the column, three Tosoh product names "TSKgel SuperMultipore HZ-H" were connected, and a Tosoh product name "TSKguardcolum SuperMP (HZ) -H" was connected and used as a guard column in front of the column. Using THF as an eluent, 200 μL of the sample solution was injected into the device for measurement. As the column, a guard column: a trade name "TSKguardcolumn SuperH-H" manufactured by Tosoh Corporation, and a column: a trade name "TSKgel SuperH5000", "TSKgel SuperH6000", and "TSKgel SuperH7000" manufactured by Tosoh Co., Ltd. were used. Chromatograms were obtained by measurement using an RI detector (HLC8020 manufactured by Tosoh Corporation) under the conditions of a column oven temperature of 40 ° C. and a THF flow rate of 1.0 mL / min.
GPC measurement conditions using a silica-based column: Using the trade name "HLC-8320 GPC" manufactured by Tosoh Corporation, using THF as an eluent, injecting 50 μL of the sample solution into the apparatus, column oven temperature 40 ° C., THF flow rate. Chromatograms were obtained using an RI detector under the condition of 0.5 ml / min. The column is used by connecting the product names "Zorbox PSM-1000S", "PSM-300S", and "PSM-60S", and the product name "DIOL 4.6 x 12.5 mm 5 micron" is used as a guard column in front of the column. Used by connecting.
Calculation method of modification rate: The peak area of the sample is P1, the peak area of standard polystyrene is P2, and the peak area of the chromatogram using the silica column is 100, assuming that the total peak area of the chromatogram using the polystyrene column is 100. The modification rate (%) was calculated from the following formula, assuming that the whole was 100, the peak area of the sample was P3, and the peak area of the standard polystyrene was P4.
Degeneration rate (%) = [1- (P2 × P3) / (P1 × P4)] × 100
(Here, P1 + P2 = P3 + P4 = 100.)

[Example 1]
<Initiator preparation process>
A tank reactor with an internal volume of 230 mL (volume 207 mL excluding the volume of the stirring blade), an inner diameter of 53 mm, and a length of 105 mm, with a width of 20 mm and a diameter of 40 mm having the lowermost end 15 mm above the bottom of the reactor. A reactor equipped with a rotary stirrer having a rotation speed of 100 rpm and having two upper and lower stages of stirring blades composed of a stirring blade having a width of 20 mm and a diameter of 40 mm with the uppermost end 15 mm below the top of the blade and the reactor. Using. That is, a cyclohexane solution of piperidine as a secondary amine and n-butyllithium as an organic lithium was used, and cyclohexane was used as a solvent, and each was continuously introduced into the reactor at a constant supply rate. Piperidine and cyclohexane were previously combined in a pipe in front of the reactor to form a mixed solution, and each solution was introduced from two nozzles provided at the bottom and discharged from one nozzle at the top. That is, the introduction nozzle was provided 15 mm below the lowermost end of the stirring blade, and the discharge nozzle was provided 15 mm above the uppermost end of the stirring blade. Table 1 shows the average supply rate of each component. Here, the average supply rate of n-butyllithium (normal butyllithium) indicates the average supply rate of the cyclohexane solution of normal butyllithium, and the average supply rate of piperidine (supply amine) is the average supply rate before merging with cyclohexane. Shown.
The lithium concentration in the reactor was 0.16% by mass, the molar ratio of piperidine to n-butyl lithium was 0.9: 1, and the average residence time of the reaction product was 13.5 minutes. The temperature of the introduced piperidine solution and the n-butyl solution was 15 ° C., respectively, and the temperature of the reaction solution at the outlet was 26 ° C.
As a result of analyzing the solution sampled from the outlet of the reactor by gas chromatography, the conversion rate of the secondary amine was 99.2%. In addition, when the initiator solution sampled in a nitrogen atmosphere was visually observed, no poorly soluble substance was found.
The residence time until the initiator solution obtained as described above was transferred from the reactor to the polymer (indicated as "residence time to the polymerization reactor" in Table 1) was 2.0 minutes.

<Polymerization process>
It has an internal volume of 110 L, an internal height (L) to diameter (D) ratio (L / D) of 4.0, an inlet at the bottom and an outlet at the top, for a stirrer and temperature control. A tank-type pressure vessel having a jacket was used as a polymerization reactor. Pre-dehydrated 1,3-butadiene, 263 g / min, styrene: 197 g / min, n-hexane: 2779 g / min, and 2,2-bis (2-oxolanyl) propane as polar substances: 0.219 g / min. In a static mixer provided in the middle of a pipe that continuously mixes at a feed rate of 1 minute and supplies this mixed solution to the inlet of the reaction group, n-butyllithium (in Table 1, in Table 1) is used as an organic metal for treating residual impurities. "Impurity-treated NBL") was added at 0.854 mmol / min, mixed, and then continuously supplied to the bottom of the reactive group. Further, 1,3-butadiene (indicated as "increment Bd" in Table 1) at 87.5 g / min and n-hexane (indicated as "increment nHex" in Table 1) at 204 g / min. , The mixed solution was supplied from the bottom of the polymerization reactor through a nozzle at a height of 2/3 of the whole. The polymerization initiator containing aminolithium obtained in the initiator preparation step is continuously supplied as total lithium at a rate of 2.74 mmol / min to the bottom of the polymerization reactor, which is vigorously mixed with a stirrer, from another nozzle. The polymerization reaction was continued.
The total lithium includes both amide lithium and unreacted n-butyllithium. The temperature was controlled so that the temperature of the polymerization solution at the outlet of the top of the reactor was 75 ° C. When the polymerization was sufficiently stable, a small amount of the modified polymer (started modified polymer) solution before the step of adding the terminal modifier was withdrawn from the outlet at the top of the reactor, and 0.2 g of antioxidant (BHT) was added per 100 g of the polymer. After the addition, the solvent was removed, and the molecular weight and the denaturation rate were measured. Other physical properties are also shown in Table 1.

<Terminal denaturation process>
Next, in the modified polymer solution flowing out from the outlet of the reactor, 2,2-dimethoxy-1- (3-trimethoxycisilylpropyl) -1-aza-2-silacyclopentane (DTMPAS) was added as a terminal modifier. Was continuously added at a rate of 0.680 mmol / min, and the polymer solution to which the terminal denaturant was added was mixed through a static mixer to denature the terminal end. Antioxidant (BHT) is continuously added at 0.055 g / min (n-hexane solution) so as to be 0.2 g per 100 g of the polymer to the polymer solution having the modified end ends, and the coupling reaction is carried out. finished. At the same time as the antioxidant, oil (JOMO Process NC140 manufactured by JX Nippon Oil & Energy Co., Ltd.) was continuously added to 100 g of the polymer so as to be 25.0 g, and mixed with a static mixer. The solvent was removed by steam stripping to obtain a modified conjugated diene polymer (Sample A). Table 1 shows the physical properties of sample A.

[Example 2]
<Initiator preparation process>
Using a static mixer-type reactor with an internal volume of 34.2 mL (volume excluding the volume of the element, 31 mL), an inner diameter of 11 mm, a length of 360 mm, and an number of elements of 21, piperidine as the secondary amine and n as the organic lithium. -Butyllithium was used and introduced continuously into the reactor as cyclohexane solutions, respectively.
The lithium concentration in the reactor was 0.16% by mass, the molar ratio of piperidine to n-butyl lithium was 0.6: 1, and the average residence time of the reaction product was 2 minutes. The temperature of the introduced piperidine solution and the n-butyl solution was 15 ° C., respectively, and the temperature of the reaction solution at the outlet was 25 ° C.
As a result of analyzing the solution sampled from the reactor outlet by gas chromatography, the reaction rate of the secondary amine was 98.9%. In addition, when the initiator solution sampled in a nitrogen atmosphere was visually observed, no poorly soluble substance was found.

<Polymerization process and terminal modification process>
Continuous polymerization was carried out in the same manner as in Example 1 except that bis (3-trimethoxysilylpropyl) methylamine (BTESPA) was used as the terminal denaturant, and after the terminal denaturant was reacted, the antioxidant and the oil were added. In addition, the solvent was removed by steam stripping to obtain a modified conjugated diene polymer (Sample B). Table 1 shows the physical properties of sample B.

[Example 3]
<Initiator preparation process>
A tank reactor with an internal volume of 525 mL (volume 473 mL excluding the volume of the stirring blade), an inner diameter of 69 mm, and a length of 139 mm. The width is 25 mm and the top of the reactor is 20 mm above the bottom of the reactor. Using a reactor equipped with a rotary stirrer having a width of 25 mm, a diameter of 50 mm, and a rotation speed of 60 rpm, with the uppermost end 20 mm below the surface, as secondary amines, piperidin and organolithium. Using n-butyllithium, each was continuously introduced into the reactor as a cyclohexane solution. Each cyclohexane solution was introduced from two nozzles provided at the bottom and discharged from one nozzle at the top. That is, the introduction nozzle was provided 20 mm below the lowermost end of the stirring blade, and the discharge nozzle was provided 20 mm above the uppermost end of the stirring blade.
The lithium concentration in the reactor was 0.16% by mass, the molar ratio of piperidine to n-butyl lithium was 0.9: 1, and the average residence time of the reaction product was 30.9 minutes. The temperature of the introduced piperidine solution and the n-butyl solution was 15 ° C., respectively, and the temperature of the reaction solution at the outlet was 26 ° C.
As a result of analyzing the solution sampled from the outlet of the reactor by gas chromatography, the reaction rate of the secondary amine was 99.4%. In addition, when the initiator solution sampled in a nitrogen atmosphere was visually observed, no poorly soluble substance was found.

<Polymerization process and terminal modification process>
Continuous polymerization was carried out in the same manner as in Example 1, an antioxidant and an oil were added after the terminal modifier was reacted, and the solvent was removed by steam stripping to obtain a modified conjugated diene polymer (Sample C). It was. Table 1 shows the physical properties of Sample C.

[Example 4]
<Initiator preparation process>
When the cyclohexane solution of secondary amine and the cyclohexane solution of organolithium are continuously introduced into the reactor, each cyclohexane solution is introduced from two nozzles provided at a height of 25 mm from the bottom and 25 mm from the top. The initiator was prepared in the same manner as in Example 1 except that the initiator was discharged from one nozzle provided at a lowered height. That is, the introduction nozzle is at the height of the lower stirring blade and the discharge nozzle is at the height of the upper stirring blade.
The temperature of the introduced piperidine solution and the n-butyl solution was 15 ° C., respectively, and the temperature of the reaction solution at the outlet was 26 ° C.
As a result of analyzing the solution sampled from the reactor outlet by gas chromatography, the reaction rate of the secondary amine was 97.7%. In addition, when the initiator solution sampled in a nitrogen atmosphere was visually observed, no poorly soluble substance was found.

<Polymerization process and terminal modification process>
Continuous polymerization was carried out in the same manner as in Example 1, an antioxidant and an oil were added after the terminal modifier was reacted, and the solvent was removed by steam stripping to obtain a modified conjugated diene polymer (Sample D). It was. Table 1 shows the physical properties of sample D.

[Example 5]
<Initiator preparation process>
An initiator was prepared in the same manner as in Example 1. As a result of analyzing the solution sampled from the reactor outlet by gas chromatography, the reaction rate of the secondary amine was 99.1%. In addition, when the initiator solution sampled in a nitrogen atmosphere was visually observed, no poorly soluble substance was found.

<Polymerization process and terminal modification process>
Continuous polymerization was carried out in the same manner as in Example 1 except that n-butyllithium as an organic metal for the residual impurity inert treatment was not added, and after the terminal denaturant was reacted, an antioxidant and oil were added, and steam strike was performed. The solvent was removed by ripping to obtain a modified conjugated diene polymer (Sample E). Table 1 shows the physical properties of sample E.

[Example 6]
<Initiator preparation process>
Using a static mixer-type reactor with an internal volume of 34.2 mL (volume excluding the volume of the element, 31 mL), an inner diameter of 11 mm, a length of 360 mm, and an number of elements of 21, piperidine as the secondary amine and n as the organic lithium. -Butyllithium was used and introduced continuously into the reactor as cyclohexane solutions, respectively.
The lithium concentration in the reactor was 1.1% by mass, the molar ratio of piperidine to n-butyllithium was 0.9: 1, and the average residence time of the reaction product was 15.4 minutes. The temperature of the introduced piperidine solution and the n-butyl solution was 15 ° C., respectively, and the temperature of the reaction solution at the outlet was 25 ° C.
As a result of analyzing the solution sampled from the reactor outlet by gas chromatography, the reaction rate of the secondary amine was 99.5%. In addition, when the initiator solution sampled in a nitrogen atmosphere was visually observed, no poorly soluble substance was found.

<Polymerization process and terminal modification process>
Continuous polymerization was carried out in the same manner as in Example 1, an antioxidant and an oil were added after the terminal modifier was reacted, and the solvent was removed by steam stripping to obtain a modified conjugated diene polymer (Sample F). It was. Table 1 shows the physical properties of sample F.

[Comparative Example 1]
<Initiator preparation process>
A tank reactor with an internal volume of 1150 mL (volume of 1035 mL excluding the volume of the stirring blade), an inner diameter of 90 mm, and a length of 180 mm. The width is 30 mm and the top of the reactor is 25 mm above the bottom of the reactor. Using a reactor equipped with a rotary stirrer having two stirring blades with a width of 30 mm and a diameter of 70 mm and a rotation speed of 60 rpm, with the uppermost end 25 mm below the surface, piperidin as a secondary amine and n as an organic lithium. -Butyllithium was used and each was continuously introduced into the reactor as a cyclohexane solution. Each cyclohexane solution was introduced from two nozzles provided at the bottom and discharged from one nozzle at the top. That is, the introduction nozzle was provided 25 mm below the lowermost end of the stirring blade, and the discharge nozzle was provided 25 mm above the uppermost end of the stirring blade.
The lithium concentration in the reactor was 0.16% by mass, the molar ratio of piperidine to n-butyl lithium was 0.9: 1, and the average residence time of the reaction product was 67.7 minutes. The temperature of the introduced piperidine solution and the n-butyl solution was 15 ° C., respectively, and the temperature of the reaction solution at the outlet was 26 ° C.
As a result of analyzing the solution sampled from the reactor outlet by gas chromatography, the reaction rate of the secondary amine was 99.6%. Moreover, when the initiator solution sampled in a nitrogen atmosphere was visually inspected, a poorly soluble substance was confirmed.
As described above, in Comparative Example 1, since the average supply rate of each reaction raw material with respect to the volume of the reactor was relatively small, the average residence time was more than 1 hour, and a poorly soluble substance was generated in the initiator solution. It is considered to be.

<Polymerization process and terminal modification process>
Continuous polymerization was carried out in the same manner as in Example 1, an antioxidant and an oil were added after the terminal modifier was reacted, and the solvent was removed by steam stripping to obtain a modified conjugated diene polymer (Sample G). It was. Table 1 shows the physical properties of sample G.

[Comparative Example 2]
<Initiator preparation process>
Using a static mixer-type reactor with an internal volume of 34.2 mL (volume excluding the volume of the element, 31 mL), an inner diameter of 11 mm, a length of 360 mm, and an number of elements of 21, piperidine as the secondary amine and n as the organic lithium. -Butyllithium was used and introduced continuously into the reactor as cyclohexane solutions, respectively.
The lithium concentration in the reactor was 3.5% by mass, the molar ratio of piperidine to n-butyllithium was 0.6: 1, and the average residence time of the reaction product was 66.9 minutes. The temperature of the introduced piperidine solution and the n-butyl solution was 15 ° C., respectively, and the temperature of the reaction solution at the outlet was 25 ° C.
As a result of analyzing the solution sampled from the reactor outlet by gas chromatography, the reaction rate of the secondary amine was 99.8%. Moreover, when the initiator solution sampled in a nitrogen atmosphere was visually inspected, a poorly soluble substance was confirmed.
As described above, in Comparative Example 2, the lithium concentration was high, and the average residence time was more than 1 hour, and it is considered that a poorly soluble substance was generated in the initiator solution.

<Polymerization process and terminal modification process>
Continuous polymerization was carried out in the same manner as in Example 1, an antioxidant and an oil were added after the terminal modifier was reacted, and the solvent was removed by steam stripping to obtain a modified conjugated diene polymer (Sample H). It was. Table 1 shows the physical properties of sample H.

In Table 1, "NBL" indicates n-butyllithium, "Bd" indicates 1,3-butadiene, "St" indicates styrene, "nHex" indicates n-hexane, and "PS" indicates polystyrene. Is shown.

(Examples 1 to 6 and Comparative Examples 1 to 2)
Using (Samples A to H) shown in Table 1 as raw rubbers, rubber compositions containing the respective raw rubbers were obtained according to the formulations shown below.
Modified conjugated diene polymer (Samples A to F): 100 parts by mass (without oil)
Silica 1 (trade name "Ultrasil 7000GR" manufactured by Ebonic Degusa): nitrogen adsorption specific surface area 170 m2 / g): 50.0 parts by mass Silica 2 (trade name "Zeosil Premium 200MP" manufactured by Rhodia) : 25.0 parts by mass carbon black (trade name "Seest KH (N339)" manufactured by Tokai Carbon Co., Ltd.): 5.0 parts by mass silane coupling agent (trade name "Si75" manufactured by Ebonic Degusa), bis (triethoxy) Cyrilpropyl) disulfide): 6.0 parts by mass S-RAE oil (trade name "Process NC140" manufactured by JX Nikko Nisseki Energy Co., Ltd.): 37.5 parts by mass Zinc flower: 2.5 parts by mass Steeric acid: 1. 0 parts by mass Anti-aging agent (N- (1,3-dimethylbutyl) -N'-phenyl-p-phenylenediamine): 2.0 parts by mass Sulfur: 2.2 parts by mass Sulfurization accelerator 1 (N-cyclohexyl) -2-benzothiadyl sulfine amide): 1.7 parts by mass Refrigeration accelerator 2 (diphenylguanidine): 2.0 parts by mass Total: 239.4 parts by mass

The above-mentioned materials were kneaded by the following method to obtain a rubber composition. Using a closed kneader equipped with a temperature control device (content capacity 0.3L), the first stage kneading is a modified conjugated diene-based weight as a raw material rubber under the conditions of a filling rate of 65% and a rotor rotation speed of 30 to 50 rpm. The coalescence (samples A to F), filler (silica 1, silica 2, carbon black), silane coupling agent, process oil, zinc oxide, and stearic acid were kneaded. At this time, the temperature of the closed mixer was controlled, and each rubber composition (blending) was obtained at an discharge temperature of 155 to 160 ° C.

Next, as the second-stage kneading, the formulation obtained above was cooled to room temperature, an antiaging agent was added, and the mixture was kneaded again in order to improve the dispersion of silica. In this case as well, the discharge temperature of the compound was adjusted to 155 to 160 ° C. by controlling the temperature of the mixer. After cooling, sulfur and vulcanization accelerators 1 and 2 were added and kneaded by an open roll set at 70 ° C. as the third stage kneading. Then, it was molded and vulcanized in a vulcanization press at 160 ° C. for 20 minutes. The rubber composition before vulcanization and the rubber composition after vulcanization were evaluated. Specifically, it was evaluated by the following method. The results are shown in Table 2.

(Evaluation) Viscoelasticity parameters The viscoelasticity parameters were measured in the torsion mode using a viscoelasticity tester "ARES" manufactured by Leometrics Scientific. Each measured value was indexed with the result for the rubber composition of Comparative Example 1 as 100. Tan δ measured at 0 ° C. at a frequency of 10 Hz and a strain of 1% was used as an index of wet grip. The larger the value, the better the wet grip property. Further, tan δ measured at 50 ° C. at a frequency of 10 Hz and a strain of 3% was used as an index of fuel efficiency. The smaller the value, the better the fuel efficiency.

As shown in Table 2, the modified conjugated diene-based polymers of Examples 1 to 6 are compared with the modified conjugated diene-based polymers of Comparative Examples 1 and 2, and when they are vulcanized, they have less wet grip and are less It was confirmed that the balance of fuel efficiency was excellent.

The modified conjugated diene polymer efficiently obtained by the continuous production method of the modified diene polymer according to the present invention can be applied as a vulcanized rubber having good physical properties, and can be applied to tire treads, automobile interior / exterior parts, and protection. It has industrial potential in fields such as rubber rubber, belts, footwear, foam bodies, and various industrial supplies.

1 1st introduction part 2 2nd introduction part 3 Derivation part 4 Top part of stirring blade 5 Bottom part of stirring blade 6 Rotary stirrer 10 Tank type reactor L Length of tank type reactor D Diameter of tank type reactor

Claims (8)

A preparation step of continuously reacting organolithium with a secondary amine in an inert organic solvent to obtain an initiator solution containing aminolithium.
The step of continuously introducing the initiator solution into the polymerizer and
A step of continuously introducing a polymerization monomer containing 50 to 100 parts of a conjugated diene monomer and 50 to 0 parts of a copolymerizable monomer into the polymerizer.
A polymerization step of homopolymerizing or copolymerizing the polymerization monomer in an inert organic solvent to obtain a polymer solution.
A step of continuously discharging the polymer solution from the polymerizer and
Including
The preparation step includes a first introduction section for introducing the organolithium, a second introduction section for introducing the secondary amine, a derivation section for deriving the initiator solution, and the organolithium and the secondary. It is carried out in a reactor comprising a mixing means for stirring the amine and the inert organic solvent.
A method for continuously producing a modified diene polymer, wherein the average residence time of the initiator solution in the preparation step is 1 hour or less. The method for continuously producing a modified diene polymer according to claim 1, wherein the reactor is a tank-type reactor including a rotary stirrer as the mixing means. The rotary stirrer is arranged perpendicular to the tank reactor.
The first introduction portion and the second introduction portion are located below the lowermost end of the stirring blade in the rotary stirrer, and the outlet portion is located above the uppermost end of the stirring blade. The method for continuously producing a modified diene polymer according to claim 2. The method for continuously producing a modified diene polymer according to claim 1, wherein the mixing means is a static mixer. Any of claims 1 to 4, wherein in the preparation step, the temperature difference between the first introduction section and the second introduction section and the lead-out section is detected, and the reaction rate between the organolithium and the secondary amine is adjusted. The method for continuously producing a modified polymer according to item 1. A step of inactivating impurities contained in the polymerization monomer by mixing an organometallic compound with the polymerization monomer or a solution of the polymerization monomer.
The step of introducing the polymerization monomer or the solution of the polymerization monomer after the inactivation into the polymerizer, and
The method for continuously producing a modified diene polymer according to any one of claims 1 to 5, further comprising. A modification step of continuously adding a terminal modifier to the polymer solution, and
A step of removing the solvent from the polymer solution that has undergone the modification step, and a step of removing the solvent.
The method for continuously producing a modified diene polymer according to any one of claims 1 to 6, further comprising. The continuous modified diene polymer according to any one of claims 1 to 7, wherein in the preparation step, the lithium concentration of the initiator solution calculated by the following formula is 0.01% to 3%. Manufacturing method.
Lithium concentration (%) = (average supply rate of the organic lithium) / (total average supply rate of all components supplied to the reactor) × (lithium atomic weight) / (molecular weight of the organic lithium) × 100