JPS5915415A - Production of reinforced polybutadiene - Google Patents

Abstract

PURPOSE:To decrease polymer deposition on a polymerization vessel and to make it possible to perform continuous polymerization for a long time, by subjecting 1,3-butadiene first to cis-1,4-polymerization and then to 1,2-polymerization while adding catalytic components in a specified order to an inert organic solvent. CONSTITUTION:1,3-Butadiene, a solvent and CS2 are mixed together; then the water concentration of the mixture is adjusted; after the addition of a halogen- containing organoaluminum compound, the mixture is aged for at least 1min in the absence of a cobalt compound; and then, after the addition of a cobalt compound, the resulting solution is mixed under agitation to polymerize the 1,3- butadiene into cis-1,4-polybutadiene. Then, an organoaluminum compound together with, if necessary, a cobalt compound is added to the above produced polymerization reaction mixture, and the resulting mixture is mixed with agitation to effect 1,2-polymerization. Part of the produced reinforced polybutadiene is separated, and the remainder is distilled to remove high-boiling matter, and a mixture of unreacted butadiene, solvent and CS2 is recirculated to the initial step.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a reinforced polybutadiene rubber comprising 5 to 3% of boiling n-hexane insoluble matter.

Cis-1.4 polybutadiene obtained by polymerizing 1,3-butadiene in the presence of a cis-1.4 polymerization catalyst is produced in large quantities as a raw material for rubber products such as tires. The physical properties of rubber products obtained from cis-1.4 polybutadiene are superior to products made from natural rubber, including good impact resilience, low calorific value, and superior abrasion resistance. Being excellent. This is one of the reasons why cis-1.4 polybutadiene is used in large quantities.

However, cis-1.4 polybutadiene has the disadvantage that the rubber products obtained therefrom have low tear strength and low flex crack growth resistance.

A polybutadiene rubber that improves the drawbacks of this cis-1,4 polybutadiene is used to convert 1,3-butadiene into a polybutadiene rubber. Polymerization is performed in the presence of a 4-polymerization catalyst to produce cis-1.4 polybutadiene, followed by 1.

A new polybutadiene obtained by polymerizing 1,3-butadiene in the presence of a dipolymerization catalyst has been proposed (Japanese Patent Publication No. 17666/1983).

The above publication describes an experimental example of the production of polybutadiene, which exhibits high tear strength and excellent flex crack growth resistance when vulcanized.

However, the method for producing polybutadiene described in the above publication uses carbon disulfide as a component of the 1.2 polymerization catalyst, and this carbon disulfide d, 1, and 2 is added to the polymerization tank, and 1M After the completion of the reaction, carbon disulfide is mixed with 1,3-butadiene or an inert organic solvent.

In particular, it is difficult to completely separate 1,3-butadiene by distillation; When carbon disulfide d comes into contact with a halogen-containing organoaluminum compound in the absence of moisture, a plow reaction occurs in the coexistence of 1% cobalt compound, and the side reaction products produced by this side reaction are 1. 3
- Because it significantly impairs the cis-1,4 polymerization of butadiene. Carbon disulfide is difficult to handle, and (2) polymer tends to adhere to the inside of the double polymerization tank, making continuous operation for long periods of time difficult. Therefore, it has been difficult to commercialize the production of polybutadiene.

Therefore, the inventors... This invention was completed as a result of intensive research aimed at providing a continuous production method for polybutadiene rubber having the above-mentioned excellent physical properties.

In other words, this invention... 1 in an inert organic solvent.

In a method of cis-1.4 polymerization and then cis-1.2 polymerization of 3-butadiene.

(a) Mixing 1,3-butadiene, an inert organic solvent, and carbon disulfide in a ratio of 20 mmol or less per 1 of the total amount of the 1,3-butadiene and inert organic solvent.

(b) Adjusting the concentration of water in the obtained liquid mixture.

(c) To the obtained solution, an organo-aluminum compound containing a cis-1.4 polymerization catalyst, which is a component of the cis-1.4 polymerization catalyst, is added. After aging the resulting mixture for 1 minute or more in the absence of a cobalt compound.

(d) Add a cobalt compound, which is a component of 110 of the cis-1,4 polymerization catalyst, and stir and mix the resulting solution.
, 1,3-butadiene is polymerized to produce cis-1,4 polybutadiene.

(e) In the obtained polymerization reaction mixture, a compound of the general formula ' (wherein R is an alkyl group having 1 to 6 carbon atoms, a phenyl group, or a cyclo An organoaluminum compound represented by an alkyl group) and optionally a cobalt compound, which is a component of the polymerization catalyst in 1.2, are added.

The resulting solution is stirred and mixed until boiling n-hexane soluble 5
~30] i quantity and boiling n-hexane J solubility 95~70
A final polybutadiene rubber consisting of heavy Ji% is produced.

(f) After adding a polymerization terminator to the obtained polymerization reaction mixture to stop the weight of 1,3-butadiene, the solid content of polybutadiene rubber is separated and obtained, and (g) the remaining unreacted from a mixture containing 1,3-butadiene, an inert organic solvent and carbon disulfide.

By distillation, carbon disulfide and 1,3-butadiene or inert solvent (without separating from residual solvent).

1. 3-Butadiene, an inert organic solvent, and carbon disulfide are obtained as fractions, and these are recycled to the above step (a).

The present invention relates to a method for producing reinforced polybutadiene rubber characterized by the following.

According to the method of this invention, despite the presence of carbon disulfide in the polymerization system during the cis-1,4 polymerization, the cis-1,4 polymerization is not adversely affected, rather the activity of the cis-1,4 polymerization catalyst is It is possible to suppress the formation of gel during cis-1,4 polymerization, and prevent polymer (including gel) from entering the cis-polymerization tank.
In addition, since the concentration of carbon disulfide is uniform in the 2-polymerization tank, the polymerization reaction of 1,3-butadiene by the 1,2-polymerization catalyst can be suppressed. The polymerization becomes uniform, and the total continuous polymerization time of cis polymerization and 1.2 polymerization can be extended. Furthermore, according to the method of the present invention, it is not necessary to separate and remove carbon disulfide after the completion of one polymerization reaction, so there is no need for equipment to separate and remove carbon disulfide, and carbon disulfide can be recycled and used. .

In the method of this invention, in step (a).

1.3-butadiene and an inert organic solvent;
The total amount of butadiene and inert organic solvent] is 20
It is necessary to admix carbon disulfide in sub-millimol proportions, preferably from 0.01 to 10 mmol.

Even if the amount of carbon disulfide, which is a component of the mono- and di-polymerization catalyst, to be mixed is greater than the above amount.

1.2 It is not preferable because the polymerization activity of the polymerization catalyst does not improve, but rather increases the amount of unrecovered carbon disulfide. The above-mentioned inert organic solvent may be any organic solvent that can dissolve cis-1,4 polybutadiene. Especially if the restriction 'cJ, l:r,
Aromatic hydrocarbons such as squid, hensen, toluene, and quinolene, aliphatic hydrocarbons such as n-heptane and n-hexano, alicyclic hydrocarbons such as cyclohexane and cyclopentane, and their halides9 e.g. Examples include methylene chloride and chlorobenzene.

A combination of an inert organic solvent and 1,3-phytadiene is.

The maximal amount of inert organic solvent and 1,3-phytadiene (
The ratio of 1,3-butadiene to 2:75; preferably 3 to 40 by weight.

The method of this invention includes 1. In A, (b) process (two I,
At X.

The concentration of water in the mixed solution obtained as described above is adjusted. In the method of this invention (=Oshiz), if a predetermined amount of water already exists in one mixed liquid (2), you can move on to the next step (C). .

It is preferable that the water content be contained at a concentration of 5 to 5 mmol.As a method for adjusting the concentration of water, a method known per se can be adopted.

In the method of this invention, after adjusting the concentration of water in one solution, in step (C), one component of the cis-1,4 polymerization catalyst is added to the solution. Adding an organoaluminum compound containing a certain amount of alcohol? The resulting mixture is aged in the absence of cobalt compounds for at least 21 minutes.

In this invention, according to the above method (2), a 6L mixture to which a roquine-containing organoaluminum compound is added,
It is necessary to ripen the product in the absence of cobalt compounds, which improves the activity of the cis-1,4-ton interpolator and suppresses the formation of gel Lnia) in the presence of cis-heavy metals. It is possible to suppress the adhesion of J-' (including J-' IJ mama-gel) into the cis polymerization tank, thereby extending the total continuous polymerization time including not only cis polymerization but also 1.2 polymerization. be able to. The above-mentioned aging effect is remarkable when no water is added to the solution after aging. 1.3
- Even if a mixture containing no butadiene is aged, or a mixture containing an IZ compound added instead of an organoaluminum compound containing no. Q/J Saku, it is not possible to suppress the adhesion of polymer into the cis polymerization tank.

Halogen-containing organoaluminum compounds may ≤ force 11
The time for aging the mixed liquid is 1 minute or more, 9. The aging time is 2 minutes to 2 hours, and the aging temperature is 10 to 80℃.
, 1-0 to 50°C is particularly preferable. If the aging time is less than 1 minute, the effect of aging will be reduced.

Examples of the halogen-containing organoaluminum compound that is a component of the cis-1,4 polymerization catalyst include diethylaluminum monochloride, diethylaluminium monobromide, diisobutylaluminum monochloride, and ethylaluminum sesquichloride. Among these, monochloride is preferred.

What is the amount of the halogen-containing organoaluminum compound used?

],] 1 mole or more, preferably 0.5 to 50 mmol per mole of 3-butadiene.

After ripening a mixture obtained by adding a halogen-containing organoaluminum compound to an inert organic solvent solution containing 1.3-butadiene and water, preferably after cooling the obtained aged solution to 10° C. or lower.

In step (d), a cobalt compound, which is one of the components of the cis-1,4 polymerization catalyst, is added, and the resulting solution is stirred and mixed to polymerize 1,3-butadiene to produce cis-1,4 polybutadiene. Generate.

The cobalt compound which is a component of the cis-1,4 polymerization catalyst may be of any type as long as it is soluble in the inert organic solvent used. For example, such cobalt compounds include cobalt β-diketone complexes of cobal) (I+) acetylacetonate, cobalt β-diketone complexes of cobal) (Ill) acetylacetonato, and cobalt such as cobalt acetoacetic acid ethyl ester complexes. β-keto acid ester complex, cobalt octoate, cobalt naphthene
), cobalt salts of organic carboxylic acids having 6 or more carbon atoms such as cobalt benzoate, cobalt chloride pyridine complexes, cobalt halide complexes such as cobalt chloride ethyl alcohol complexes, and the like.

The amount of cobalt compound used is 0.001 mmol or more per 1 mole of 1.3-butadiene. ='? Nio,.

It is preferable that the amount of O is 5 mmol or more.

In addition, the molar ratio of the halogen-precipitated organoaluminum compound to the cobalt compound (AQ/ co ) 13.5
It is particularly preferable that the number is 15 or more.

In the method of the invention, the polymerization temperature i(1:.

The temperature is preferably -20 to 80°C, particularly 5 to 50°C. The polymerization pressure may be either normal pressure or increased pressure, and one polymerization time (average residence time in the polymerization tank) is preferably in the range of 10 minutes to 10 hours. Further, cis polymerization is carried out by stirring and mixing the solution in a cis polymerization reaction tank. As the polymerization reaction tank used for cis polymerization, the polymerization reaction tank 1 equipped with a high viscosity liquid stirring device, for example, the device described in Japanese Patent Publication No. 40-2645, can be used.

The above cis polymerization has a cis-1,4 structure content of 90 or more, particularly 95q6 or more, and an intrinsic viscosity of toluene at 30°C [η
)? zwy is 1.5-8. In particular, cis-
It is preferable to carry out the reaction so that 1,4 polybutadiene is produced. [η)? To set tvxy to an appropriate value.

Known Molecular Weight Modifiers 1 For example, non-conjugated dienes such as cyclooctadiene, iso, or ethylene.

Alpha-olefins such as propylene, butene-1, etc. can be used. Additionally, a known gel inhibitor can be used to further suppress the formation of gel during cis polymerization.

In the method of this invention, in the (θ) step.

cis-1,4 polybutadiene obtained in the cis polymerization process,
Into the polymerization reaction mixture containing the cis-1,4 polymerization catalyst and carbon disulfide, an organoaluminum compound represented by the general formula AQR3, which is a component of the 1゜2 polymerization catalyst other than the carbon disulfide, and optionally 1. .2 A cobalt compound, which is one of the components of the polymerization catalyst pond, is added, and the resulting solution is stirred and mixed to polymerize 1,3-butadiene, and 5 to 3 bundles of boiling n-hexane insolubles are collected.

Examples of the organoaluminum compound represented by the general formula AJAR3, which is the aluminum component of the 1, 2 polymerization catalyst, include triethylaluminum, trimethylaluminum, and triisobutylaluminum.

Examples include triphenylaluminum.

1, 2 As a cobalt component of the polymerization catalyst, dl. The same cobalt compounds as mentioned above as a component of the cis-1,4 polymerization catalyst can be mentioned.

The amount of the 1,2 polymerization catalyst used varies depending on the type and combination of catalyst components and polymerization conditions.

1.0 cono(ruto compound) per mole of 3-butadiene
．． 0.005 mmol or more, especially 0.01 to 5 mmol: The organoaluminum compound is 0.1 mmol or more, especially 0.01 mmol or more, especially 0.01 to 5 mmol.
Preferably, the amount of carbon disulfide is 0.001 mmol or more, particularly 0.01 to 10 mmol.

In the method of this invention, when the cobalt compound of the cis polymerization catalyst and the core compound of the 1.2 polymerization catalyst are the same, the required amount of 1.2 polymerization Add the cobalt compound together.

1.2 It is also possible to select conditions in which only the organoaluminum compound is added during polymerization. Also, when the amount of carbon disulfide used in the 1°2 polymerization is insufficient by the amount of carbon disulfide mixed in step (a) (2).

In a step prior to step (e), for example, additional carbon disulfide may be added when adjusting the moisture concentration in step (b).

In the method of this invention, the Φ temperature of 1.21 is -
20-80°C, especially 5-50'C is preferred.

The polymerization pressure may be normal pressure or increased pressure, and the polymerization time is preferably in the range of 10 minutes to 10 hours. Further, 1.2 polymerization is carried out in a 1.2 polymerization tank by stirring and mixing the solution. 1
．． As a polymerization tank used for double polymerization.

1.2 During polymerization, the polymerization reaction mixture becomes even more viscous,
Since the polymer tends to adhere to the inside of the polymerization tank,
It is preferable to use a polymerization tank equipped with a scraping member as described in Japanese Patent No. 2645.

1. In the second polymerization, the concentration of 1,3-butadiene in the first polymerization system is preferably 3 to 35% by weight.

In the method of this invention, in step (f).

Step (e) above: Polymerization containing the polybutadiene rubber obtained in the 1,2 polymerization step, unreacted 1,3-butadiene, carbon dioxide, a cobalt compound, an organoaluminum compound, and an inert organic solvent. The reaction mixture is preferably supplied to a polymerization termination tank, and after terminating the polymerization by adding a polymerization terminator to the polymerization reaction mixture, the solid content of polybutadiene comb is separated and obtained.

The polymerization terminator may be any compound that reacts with an organoaluminum compound containing nitrogen and an organoaluminum compound represented by the general formula AARs.For example, alcohols such as methanol and ethanol,
Inorganic acids such as water, hydrochloric acid, and sulfuric acid.

Organic acids such as acetic acid and benzoic acid, monoethanolamine and ammonia, and to! Examples include phosphite esters such as jL (nonylphenyl) phosphite, hydrogen gas, and the like. Particularly preferred 1 polymerization terminators are:
Examples include phosphite esters.

These may be added alone to the polymerization reaction mixture (two may be added,
Water, alcohol or an inert organic solvent (a mixture of the two may be added).

1. After stopping the polymerization of 3-butadiene 1) Adding a precipitant such as methanol to the polymerization reaction mixture).

Alternatively, the solvent can be removed by evaporation without blowing in fludge (power to blow in water vapor), and a polymer having a solid Jf of 6 minutes can be precipitated and dried for 1 minute to obtain No. 1 notadiene rubber. I can do it. An anti-aging agent may be added to the polybutadiene rubber by adding the anti-aging agent to the polymerization reaction mixture after stopping the polymerization of 1,3-butadiene or to a slurry of the polybutadiene rubber. Or preferable.

The No. 2000 myrifutadiene rubber obtained by the method of the present invention has an amount insoluble in boiling n-hexane of 5 to 30% by weight, a content soluble in boiling n-hexane of 95 to 70% by weight, and a content insoluble in boiling n-hexane of 95 to 70% by weight. Melting point of insoluble matter 180-215
It is ℃.

In the method of this invention, (g) step (two steps).

A mixture containing unreacted 1,3-)゛tadiene, an inert organic solvent, and carbon disulfide (usually referred to as a recovery solvent) after separating the solid polybutadiene rubber from the polymerization reaction mixture. By distillation, carbon disulfide, 1,3-butadiene and carbon disulfide are distilled without separating the inert organic solvent. and are recycled to the above step (a).

In the above-mentioned distillation, if the inert organic solvent used has a much higher boiling point than carbon disulfide, for example, two distillation columns are used, and the first distillation column 1,3-butadiene containing a portion of carbon disulfide is obtained as a fraction, and an inert organic solvent optionally containing a small amount of carbon disulfide is obtained as a fraction by means of a second distillation column.

Alternatively, carbon disulfide and other two components, especially 1,3-butadiene, are separated by using one distillation column to obtain l,3-butadiene, an inert organic solvent, and carbon disulfide as fractions. 1,3 containing carbon disulfide without
- obtaining butadiene and an inert organic solvent as a fraction;
These are recycled to the above step (a).

Alternatively, when the inert organic solvent used has a boiling point close to that of carbon disulfide [for example, when methylene chloride is used as the inert organic solvent].

The first distillation column yields 1,3-butadiene as a fraction, optionally containing a small amount of carbon disulfide.

by a second distillation column to obtain an inert organic solvent containing most of the carbon disulfide as a fraction, or
1, 3-Butadiene, an inert organic solvent, and carbon disulfide are obtained as fractions using one distillation column,
Carbon disulfide and two other components.

In particular, 1,3-butadiene containing carbon disulfide and the inert organic solvent are obtained as a fraction without separating them from the inert organic solvent, and these are recycled to the step (a).

The 1,3-butadiene, inert organic solvent, and carbon disulfide recovered as described above are mixed with supplementary 1,23-butadiene and used.

Hereinafter, using the flow sheet of FIG. 1 showing an embodiment in which a solvent having a boiling point higher than 1,3-butadiene, such as benzene, is used as an inert organic solvent when carrying out the method of the present invention, this process will be described. The invention will be further explained. however,
This invention is not limited to the following description.

In Figure i1, 1,3-butadiene is fed from fresh 1,3-phtadiene tank 1 through conduit 20, and purified recovered solvent (1 A mixture of 3-butadiene, an inert organic solvent, and carbon disulfide is mixed in a mixer 3. The obtained mixed liquid passes through the conduit 22 to the mixer 4.
guided by.

An appropriate amount of water is supplied to the mixed liquid from the conduit 23.

Supplementary carbon disulfide is optionally supplied from conduit 24 (although not shown in the drawings, supplementary carbon disulfide is supplied from conduit 31).
It may be supplied inside. ). In the mixer 4, the mixture of 1,3-butadiene, an inert organic solvent, and carbon disulfide, water, and optionally supplemented carbon disulfide are uniformly mixed, and then passed through a conduit 25 to the aging tank 5. be guided. A halogen-containing organoaluminum compound is supplied from a conduit 26 to the mixed liquid whose water concentration has been adjusted. In the aging tank 5, a liquid mixture to which a halogen-containing organic aluminum compound is added is aged for one minute or more in the absence of a cobalt compound.

The mixed liquid aged in the aging tank 5 is as follows.

It is supplied to the cis-1,4 polymerization tank 6 via a conduit 27.

The cis-1,4 polymerization tank 6 also contains a molecular weight regulator such as cyclooctadiene.

Conduit 29 supplies an antigel agent such as dilauryl-3,3'-thiodipropione (TPI), and conduit 30 supplies a cobalt compound. In the cis-1,4 polymerization reaction tank 6, the solution is stirred and mixed to polymerize 1°3-butadiene to produce cis-1,4 polybutadiene.

The polymerization reaction mixture obtained in the cis-1,4 polymerization tank 6 is supplied to the 1.2 polymerization tank 7 via a conduit 31.

In addition, a cobalt compound is supplied from a conduit 32 to the above-mentioned 1.2 polymerization tank 7, and an organoaluminum compound represented by the general formula A [(3) is supplied from a conduit 33.The obtained solution is stirred and mixed. to polymerize 1,3-butadiene,
A final polybutadiene rubber is produced having a boiling n-hexane insoluble content of 5 to 30 weight percent and a boiling n-hexane soluble content of 95 to '70 weight percent. 1.2 In polymerization tank 7 1.3-
When butadiene is polymerized, polymers that are insoluble in inert organic solvents precipitate and the resulting polymerization reaction mixture becomes highly viscous. A polymerization tank of 1 is preferably used.

1.2 The polymerization reaction mixture obtained in the polymerization tank 7 is transferred to the conduit 34
The polymer is then supplied to the polymerization stop tank 4o via the conduit 36, and then to the reinforced polybutadiene rubber separation device 8 via the conduit 36. Furthermore, a polymerization terminator is supplied to the polymerization reaction mixture through the conduit 35 in the nine polymerization termination tank 4o to terminate the polymerization of 1,3-butadiene. As the reinforced polybutadiene rubber separation device 8 used is a device 9 known per se, for example a device combining a steam stripper and a 15 filtration vessel. Reinforced polybutadiene rubber 9 is separated from the polymerization reaction mixture by a reinforced polybutadiene rubber separator 8.
and a liquid mixture containing unreacted 1,3-butadiene, an inert organic solvent, and carbon disulfide.

The remaining liquid mixture from which the solid content of reinforced polybutadiene rubber has been separated by the reinforced polybutadiene rubber separator 8 is supplied to the distillation device 1o via a conduit 37. A mixture of carbon disulfide, 1,3-butadiene, and an inert organic solvent is separated as a fraction by this distillation apparatus 1o (which may be one distillation column or two distillation columns).
However, these fL are supplied through a conduit 38 to a recovery solvent tank 2 made of 1M.

Further, high boiling point substances 11 are removed from the distillation apparatus 10 by a portion S.

According to the method of this invention, the final product is produced (,!
:,! '1. Continuous production of reinforced polybutadiene rubber exhibiting the same physical properties! : Can be done.

Next, examples will be shown. In the description of the examples, the boiling n-hexane insoluble portion of the reinforced polybutadiene rubber is determined by dissolving the reinforcing polybutadiene rubber of 21 in 20 (,) me of n-hexane at room temperature, and then removing the insoluble portion for 4 hours. It was obtained by extracting with a Tuxlet extractor, vacuum drying the extracted residue, and accurately weighing the weight. In addition, the boiling n-hexane soluble content is obtained by evaporating and removing n-hexane from the n-hexane soluble content obtained as described above and the extractor using a Tuxley extractor, and then vacuum-drying the m-hexane solution. It was determined by weighing. In addition, reinforced polybutadiene rubber n
-Hexane soluble content and cis-1,4 structure content of polybutadiene after cis-1,4 polymerization were measured by infrared absorption spectrum (IR), and n-hexane insoluble content was 1.2-
Structural content i was measured by nuclear magnetic resonance spectroscopy (NMR), and the melting point of n-hexane insoluble components was measured using a self-recording differential calorimeter (D
SC) was determined by the peak temperature of the endothermic curve.

In addition, the n-hexane soluble content and cis] of the reinforced polybutadiene rubber, the intrinsic viscosity C of the polybutadiene after tetrapolymerization
v] is the value measured in toluene at 30°C, and the reduced viscosity ηSP/C of the n-hexane insoluble portion of the reinforced polybutadiene rubber is the value measured in toluene.

I J 5 "C* Value measured in tetralin.

Further, the content of carbon disulfide in the solution was measured and calculated using a gas chromatography equipped with a flame photometric detector manufactured by Hitachi, Ltd. and using Cromonlube 102 as a filler.

Example 1.3-Butadiene was 23.7 weight φ, carbon disulfide was 1
Water was removed from a solution of benzene at a concentration of 0 m9/l using a dehydration tower, and water was added to the resulting solution by 3811 m9/l.
After addition at a ratio of 19 (2.1 mmol)/1.

The mixture was mixed and dissolved in a mixing tank with a stirring blade. This solution was supplied to an aging tank with an internal volume of 201 and equipped with stirring blades at a rate of 50 tons per hour, and diethylaluminum monochloride was fed at a rate of 25 tons per hour. l
(209 mmol).

The mixture was aged at 35° C. for 25 minutes (average residence time).

After cooling the obtained aged liquid to -4°C, it was heated to -10°C in a stainless steel autoclave with an internal volume of 20 cm and equipped with a ribbon-type stirring blade, and the outer cylinder was equipped with a jacket for temperature control.
2 aqueous solution was supplied to the cis-1,4 polymerization tank which was circulated through the Jaqueno F at a rate of 50 t/hour, cobalt octoate at 265 mg (0.77 mmol) and 1.5-cyclooctadiene at 6 o/hour. , 5y (o, 561 mol)
, dilauryl-3,3'-thiocyclobionate was fed at 6.98 F (13.4 mmol) per hour, and 1,3-butadiene was dissolved in dis- 1,4 claws joined together.This cis-1,4i1i
The amount of polybutadiene produced per hour is 3.60
Kg, this voriptadiene has a cis-1,4 structure content of 98 or more, [η] (intrinsic viscosity, 30°C
, in toluene) was 2.0, and a 200 mesoyu wire mesh was used.

The gel content measured was 0.01% or less.

The polymerization reaction mixture obtained in the cis-1,4 polymerization tank.

The 1,2 polymerization tank, which is the same type of polymerization tank as the cis-1,4 polymerization tank, was continuously fed at a rate of 5 at/hr, and triethylaluminum was added at 27.2 F (239 mmol) and cobalt octoate/h. Every, R83e my (2,36
Polymerization temperature: 40℃, average residence time: 2
1.3-butadiene was added to 1.2 with stirring for 5 minutes.
Polymerized. The obtained polymerization reaction mixture was continuously supplied to a mixing tank equipped with stirring blades, and to this were added 2 times the mole of tribenonylphenyl) phosphite (TNP) to cobalt octoate and a small amount of water. Polymerization was stopped. Transfer this mixture to a solvent evaporation tank (steams) equipped with stirring blades.

1207/hr, hot water and 4 Ky/cMa saturated steam were fed, the mixture was dispersed in the hot water and the solvent was evaporated.

After extracting the slurry from the evaporation tank and separating water and dispersed polybutadiene debris (crumbs), the crumbs were vacuum-dried at room temperature to obtain reinforced polybutadiene rubber.

Polymerization was continued for 22 hours to obtain reinforced polybutadiene rubber having an average yield of 4.09 Kp per hour for 9 polymerization times (average residence time). This reinforced polybutadiene rubber has a boiling n-hexane insoluble content of 12.0%;
The melting point of the hexane-insoluble matter is 206°C, and the reduced viscosity is η8.
P/C (135°C, in Tetralin) is 2.0 (dL/
f ), the l,2-structure content is 92.9%, the boiling n-hexane insoluble content has a cis-1,4 structure content of 97.0%, and [η] is 2.1. Met.

After the polymerization reaction was completed, a benzene solution of 1,3-butadiene was flowed at a rate of 50 tons per hour for 30 minutes, and then the polymer adhering to the stirring blade and inner wall in the polymerization tank was scraped off, and the adhering polymer was vacuum dried. Ta. The amount of adhering polymer was 132 (22 of which was gel content) in the cis-1,4 polymerization tank, and 9Of in the 1.2 polymerization tank.

On the other hand, the solvent evaporated from the evaporation tank is cooled and condensed to separate into an aqueous phase and a solvent layer. From the obtained solvent (referred to as recovered solvent), 1,3-butadiene, benzene and carbon disulfide are extracted as follows. was collected.

1.3-butadiene in 15. ．． 5% by weight and carbon disulfide in a proportion of i 2 mg 7t.
High boiling point substances were removed from Oat by distillation to obtain 1 polymerization solvent, and 9 polymerization solvent was reused. Carbon disulfide, 1,3-butadiene, and benzene in the first recovery solvent were recovered by the distillation.

[Brief explanation of drawings]

1: Fresh 1.3-butadiene tank, 2: Purified recovery solvent tank, 3.4: Mixer, 5: Aging tank, 6
: cis-1.4 polymerization tank, 7:1,2 polymerization tank. 8: Reinforced polybutadiene rubber separation device, 9: Reinforced polybutadiene rubber, lO: Distillation device, li: High boiling point substance, 20
〜38: Conduit, 40: Polymerization stop tank FIG. 1 shows an embodiment in which a solvent having a boiling point higher than 1,3-butadiene, such as benzene, is used as an inert organic solvent when carrying out the method of the present invention. It is a schematic diagram of a flow sheet showing. Patent applicant: Ube Industries, Ltd.

Claims (1)

[Claims] 1,3-butadiene is dissolved in cis-1,4 in an inert organic solvent.
In a method of polymerizing and then 1.2 polymerizing. (a) 1,3-butadiene, an inert organic solvent, and carbon disulfide in a ratio of 20 mmol or less per 1 total amount of the 1,3-butadiene and inert organic solvent. After adding a halogen-containing organoaluminum compound, the resulting mixture was aged for 1 minute or more in the absence of a cobalt compound. Add the root compound and stir and mix the resulting solution for 1.3
- Polymerizing butadiene to produce cis-1,4 polybutadiene. (e) In the obtained polymerization reaction mixture, an organoaluminum compound represented by the carbon disulfide I R3 (wherein R is an alkyl group having 1 to 6 carbon atoms, a phenyl group, or a chloroalkyl group). and, if necessary, add the compound. The obtained solution was stirred and mixed to produce a rubber having a boiling n-hexane insoluble content of 5 to 30 parts and a boiling n-hexane soluble content of 9 to 70 parts. (f) After adding a polymerization terminator to the obtained polymerization reaction mixture to stop the polymerization of 1,3-butadiene, the solid content of polybutadiene rubber is separated and obtained. (g) From a mixture containing remaining unreacted 1,3-butadiene, an inert organic solvent and carbon disulfide. By distillation. With carbon disulfide and 1,3-butadiene or an inert organic solvent without separation. Obtain 1,3-butadiene, an inert organic solvent, and carbon fluoride as fractions, and convert these into ? fI (a) El
Circulate as needed. . A method for producing reinforced polybutadiene rubber, characterized by: