JP2002020427A - Method for producing polybutadiene - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a polybutadiene having a low gel content without causing the deposition of gel in a polymerization apparatus. SOLUTION: In a method for producing polybutadiene by polymerizing 1,3-butadiene in an inert organic solvent in the presence of a polymerization catalyst, a necessary amount of water in the form of steam and/or hot water is added to and homogeneously mixed into the inert organic solvent or a solution of 1,3-butadiene in the solvent.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing polybutadiene, which produces less gel by polymerizing 1,3-butadiene.

[0002]

2. Description of the Related Art There have been many proposals for polymerization catalysts of 1,3-butadiene. In particular, high cis-1,4-polybutadiene, that is, polybutadiene having a high cis-1,4 bond content, has been proposed. Many polymerization catalysts have been developed because of their excellent thermal and mechanical properties.

For example, Canadian Patent No. 794,860 discloses that a hydrocarbyl aluminum compound is mixed well with water, and a catalyst comprising aged mixture and cobalt dioctoate is used in a solvent containing 20% or more of benzene. A process for producing high cis-1,4-polybutadiene by polymerizing 3-butadiene is disclosed.

Japanese Patent Publication No. 38-1243 discloses a process for producing high cis-1,4-polybutadiene by polymerizing 1,3-butadiene using a catalyst comprising a cobalt compound, an acidic metal halide, an alkylaluminum compound and water. Is disclosed.

[0005] JP-B-61-54808 discloses a solvent comprising a linear or branched aliphatic hydrocarbon using a catalyst comprising diethylaluminum chloride, water and cobalt octoate. A method of polymerizing in a polymer is disclosed.

In these conventional methods, it is essential to contain water in the solvent in order to increase the catalytic activity. For example, when the organic aluminum compound of the catalyst component and water are mixed unevenly, the cation Seeds occur, 1, 3
-In the polymerization of butadiene, a gel is easily formed because of the double bond in the formed polymer, and a large amount of gel is contained in the polybutadiene, or the gel adheres to the stirring blades and the inner wall in the polymerization tank, resulting in a long time. In some cases, the polymerization reaction could not be continued for a time.

[0007] JP-A-58-101105 discloses that
The water concentration of an inert organic solvent solution of 1,3-butadiene was adjusted, a halogen-containing organoaluminum compound was added to the obtained solution, the mixture was aged for a predetermined time, and then a cobalt compound was added and polymerized to form a gel. A method for suppressing occurrence is disclosed.

Japanese Patent Application Laid-Open No. 4-85304 discloses a method in which a required amount of water is dispersed in a porous filter medium having a pore size of 5 μm or less to suppress gel formation and prevent scale adhesion.

However, the inert organic solvent and water used are not compatible with each other, and it takes a long time to obtain a uniform water-containing organic solvent.

[0010]

An object of the present invention is to provide a method for producing polybutadiene having a low gel content without adhering a gel to a polymerization apparatus.

[0011]

SUMMARY OF THE INVENTION The present invention provides a method for producing polybutadiene by polymerizing 1,3-butadiene in an inert organic solvent in the presence of a polymerization catalyst. The present invention relates to a method for producing polybutadiene, which comprises adding necessary water to an inert organic solvent solution in the form of steam and / or hot water and mixing.

The present invention also relates to the present invention, wherein the polymerization catalyst comprises (A)
Baltic compound, (B) R^Two _3-nAlX _n (Where R^Two Is charcoal
A hydrocarbon group having a prime number of 1 to 10, X represents halogen, and n is
It is a number of 1-2. Halogen containing aluminum expressed by)
Catalyst consisting of an aluminum compound and (C) water.
The present invention relates to a method for producing the above polybutadiene.

The present invention also relates to an inert solvent or 1,3-
3. A polybutadiene according to claim 2, wherein after mixing necessary water to an inert organic solvent solution of butadiene, adding a halogen-containing aluminum compound and aging, and then adding a cobalt compound and polymerizing. It relates to a manufacturing method.

Further, the present invention relates to the method for producing polybutadiene according to any one of claims 1 to 3, wherein the polybutadiene is cis-1,4-polybutadiene having a cis-1,4 structure of 80% or more. .

[0015]

DETAILED DESCRIPTION OF THE INVENTION Examples of inert organic solvents include aromatic hydrocarbons such as toluene, benzene and xylene, aliphatic hydrocarbons such as n-hexane, butane, heptane and pentane, and oils such as cyclopentane and cyclohexane. Olefinic hydrocarbons such as cyclic hydrocarbons, C4 fractions such as 1-butene, cis-2-butene and trans-2-butene; hydrocarbon solvents such as mineral spirits, solvent naphtha and kerosene; methylene chloride; And the like. Further, 1,3-butadiene itself may be used as the polymerization solvent.

Among them, benzene, cyclohexane, a mixture of cis-2-butene and trans-2-butene, and the like are preferably used.

A polymerization catalyst for 1,3-butadiene,
The method for adding water of the present invention can be applied to a polymerization reaction using a catalyst in which it is preferable to add a predetermined amount of water.

A catalyst system using a transition metal compound, for example,
Examples include a Ziegler-Natta catalyst such as a cobalt-based catalyst composition and a nickel-based catalyst composition, and a metallocene-based catalyst. As the cobalt-based catalyst composition, a cobalt compound,
A halogen-containing organoaluminum compound, and a catalyst system composed of water, as a nickel-based catalyst composition, a nickel compound, an organoaluminum compound, and a nickel-based catalyst composition composed of a fluorine compound, as a metallocene-based catalyst,
Examples include a metallocene complex of a transition metal compound of Group V of the periodic table, an ionic compound of a non-coordinating anion and a cation, an organoaluminum compound, and a catalyst system comprising water. Among them, it is suitably used for a polymerization reaction using a cobalt-based catalyst composition, a metallocene-based catalyst, or the like.

As the cobalt compound of the cobalt catalyst composition, a cobalt salt or complex is preferably used. Particularly preferred are cobalt chloride, cobalt bromide, cobalt nitrate, cobalt octylate, cobalt naphthenate,
Cobalt salts such as cobalt acetate and cobalt malonate; cobalt bisacetylacetonate and trisacetylacetonate; ethyl acetate cobalt acetoacetate; triarylphosphine complex, trialkylphosphine complex of cobalt halide, pyridine Organic base complexes such as a complex and a picoline complex, and an ethyl alcohol complex are exemplified.

As the halogen compound in the cobalt-based catalyst composition, R ² _3-n AlX _n (wherein R ² has 1 carbon atom)
X is a halogen group, and n is a number of 1-2. Examples of the halogen-containing aluminum compound represented by the formula (1) include dialkyl aluminum chlorides, dialkyl aluminum halides such as dialkyl aluminum bromide, alkyl aluminum sesquichlorides, alkyl aluminum sesquihalides such as alkyl aluminum sesquibromide, alkyl aluminum dichlorides, and alkyl aluminum dibromides. And alkylaluminum dihalide. Specific compounds include diethylaluminum monochloride, diethylaluminum monobromide, dibutylaluminum monochloride, ethylaluminum sesquichloride, ethylaluminum dichloride, dicyclohexylaluminum monochloride, diphenylaluminum monochloride and the like.

In addition, R ¹³ Al (wherein R ¹ has ^{1 to} ₃ carbon atoms)
Shows 10 hydrocarbon groups. Examples of the trialkylaluminum compound represented by triethylaluminum, trimethylaluminum, triisobutylaluminum,
Trihexyl aluminum, trioctyl aluminum and the like are also included.

Further, an aluminoxane may be used. Aluminoxane is obtained by contacting an organoaluminum compound with a condensing agent,
A chain aluminoxane represented by the general formula (-Al (R ') O-) n or a cyclic aluminoxane is exemplified.
(R ′ is a hydrocarbon group having 1 to 10 carbon atoms, including those partially substituted with a halogen atom and / or an alkoxy group. N is the degree of polymerization and is 5 or more, preferably 10 or more.) . Examples of R ′ include a methyl, ethyl, propyl and isobutyl group, and a methyl group and an ethyl group are preferred. Examples of the organoaluminum compound used as a raw material of the aluminoxane include trialkylaluminums such as trimethylaluminum, triethylaluminum, and triisobutylaluminum, and mixtures thereof.

Of these, a catalyst system comprising a cobalt compound, a halogen-containing aluminum compound and water is preferred.

When a cobalt-based catalyst composition comprising a cobalt compound, a halogen-containing organoaluminum compound, and water is used, the cobalt compound is 1 × 10 ^-7 to 1 mol per mol of 1,3-butadiene. × 10 ^-3
Preferably it is in the molar range. Further, the halogen-containing organoaluminum compound is 1 × 10 ⁻⁵ to 1 × 10 ⁵
Preferably it is in the range of ^-1 mole. The amount of water is preferably in the range of 1 × 10 ^-5 to 1 × 10 ^-1 mol.

The order of addition of the catalyst components is preferably such that water is added to an inert solvent, mixed uniformly, a halogen-containing organoaluminum compound is added, and a cobalt compound is added to initiate polymerization. . After adding the halogen-containing organoaluminum compound, it is preferable to add the cobalt compound after aging for a predetermined time. The aging time is preferably from 0.1 to 24 hours. Aging temperature is 0-80 ° C
Is preferred.

When a nickel-based catalyst composition is used, a nickel salt or complex is preferably used. Particularly preferred are nickel halides such as nickel chloride and nickel bromide, nickel salts of inorganic acids such as nickel nitrate, nickel octylate, nickel acetate, nickel carboxylate having 1 to 18 carbon atoms such as nickel octoate, Nickel complexes such as nickel naphthenate, nickel malonate, nickel bisacetylacetonate, trisacetylacetonate, ethyl acetoacetate, nickel halide triarylphosphine complex, trialkylphosphine complex, pyridine complex and picoline complex Various complexes such as an organic base complex and an ethyl alcohol complex are exemplified.

When the nickel-based catalyst composition is used, examples of the organoaluminum compound include trialkylaluminums represented by AlR ₃ (R represents a hydrocarbon group having 1 to 10 carbon atoms). Examples thereof include trimethylaluminum, triethylaluminum, tri-n-propylaluminum, triisopropylaluminum, tri-n-butylaluminum, triisobutylaluminum, tripentylaluminum,
Examples include trihexyl aluminum, tricyclohexyl aluminum, trioctyl aluminum, triphenyl aluminum, tri-p-tolyl aluminum, and tribenzyl aluminum. The three alkyl groups in the trialkylaluminum may be the same or different from each other.

As the fluorine compound when the nickel-based catalyst composition is used, an ether of boron trifluoride, an alcohol, or a complex of a mixture thereof, an ether of hydrogen fluoride, an alcohol, or a mixture of these complexes is used. Can be Particularly preferred fluorine compounds include
Boron trifluoride diethyl etherate, boron trifluoride dibutyl etherate, hydrogen fluoride diethyl etherate, and hydrogen fluoride dibutyl etherate can be mentioned.

In the metallocene catalyst, Periodic Table No. 5
Examples of the metallocene complex of a group III transition metal compound include: (1) RM · La, that is, a group V transition metal compound of the fifth group of the periodic table having an oxidation number of +1 having a ligand of a cycloalkadienyl group. (2) R _n MX _2-n · La, ie at least 1
Oxidation number having a ligand of two cycloalkadienyl groups +
2 of the periodic table group 5 transition metal compound _{(3) R n MX 3-} n · La (4) RMX 3 · La (5) RM (O) X 2 · La (6) R n MX 3-n ( NR ') and the like.
Is 1 or 2, a is 0, 1 or 2.)

In the present invention, it is preferable to add water necessary for the inert organic solvent or the solution in a steam and / or hot water state. By adding in the state of steam and / or hot water, the contact area with the inert organic solvent or the solution is large and the contact temperature is high, so that there is an effect of faster and more uniform mixing. Steam temperature is 183 ~ 220
C is preferred. The pressure is preferably 11 to 24 atm. The temperature of the hot water is preferably 50 to 220 ° C, and 100 to 200 ° C.
C is more preferred.

In the present invention, a known molecular weight regulator at the time of polymerization, for example, non-conjugated dienes such as cyclooctadiene and arene, or ethylene, propylene, butene-
Alpha-olefins such as 1 can be used.

[0032] The polymerization temperature is preferably in the range of -30 to 100 ° C, particularly preferably in the range of 30 to 80 ° C. The polymerization time is preferably in the range of 10 minutes to 12 hours, particularly preferably 30 minutes to 6 hours. The polymerization is carried out under normal pressure or under pressure up to about 10 atm (gage pressure).

After the polymerization is carried out for a predetermined time, the pressure inside the polymerization tank is released as required, and post-treatments such as washing and drying steps are performed.

According to the method of the present invention, Hycis-1,4-
Butadiene rubber (BR) such as polybutadiene, isoprene rubber (IR), styrene-butadiene rubber (SB
R), ethylene-propylene rubber (EPM), ethylene-diene rubber (EPDM), syndiotactic-1,
Solution polymerization of an elastomer such as 2-polybutadiene rubber (SPBR) is preferably applicable. In particular, cis-1,4
-Polybutadiene having a structure content of preferably 80% or more, particularly preferably 95% or more, and having little gel content can be produced. Further, the gel does not adhere to the stirring blade or the inner wall of the polymerization tank, and the polymerization can be stably performed for a long time.

[0035]

EXAMPLES Microstructure was performed by infrared absorption spectroscopy. Cis 740 cm ^-1 , transformer 967c
The microstructure was calculated from the absorption intensity ratio between m ^-1 and 1,2-910 cm ^-1 .

The gel content was such that about 5 g of the polymer was dissolved in 200 m of toluene.
After dissolving in L, this was filtered through a 250-mesh wire gauze, the wire gauze was sufficiently washed with toluene, and calculated from the weight increase of the wire gauze after vacuum drying at 80 ° C. for 5 hours.

Example 1 Steam-like (183 ° C., 10 atm) water was added to a benzene solution containing 1,3-butadiene at a concentration of 24% by weight and mixed, so that the water concentration was 1.8 mmol / L. Was adjusted. The benzene solution of the above water-containing 1,3-butadiene was placed in a 2 L stainless steel ripening tank equipped with a stirrer at a rate of 3 hours / hour.
0 L was supplied, and 112.5 mmol / h of diethyl aluminum monochloride was mixed. The obtained aging solution is -3
30 L / h into a 15 L stainless steel polymerization tank equipped with a ribbon stirrer so as not to be cooled to 0 ° C., 0.4 mmol / hr of cobalt octoate, 94.3 mmol / hr of 1,5-cyclooctadiene and TPL ( Dilauryl-
3,3′-thiodipropionate) was mixed at 6 mmol / h, and polymerized at 30 ° C. for an average residence time of 30 minutes for 36 hours. The obtained polymerization product liquid is supplied to a mixing tank with a stirrer,
To this, 2,6-di-tert-butyl-4-methylphenol was added at 1 PHR to the rubber, and a small amount of methanol was added.
After terminating the polymerization, unreacted 1,3-butadiene and the solvent were removed, followed by vacuum drying at room temperature to obtain 69.1 kg of cis-1,4 polybutadiene. This polybutadiene has an intrinsic viscosity [η] of 4.2 and a microstructure of cis-1,4 structure 9
7.6%, 1.7% of trans-1,4 structure and 0.7% of 1,2 structure. A predetermined amount of this polybutadiene was dissolved in benzene, and the gel content was measured using a 200-mesh wire net. The gel content was 0.04%. After the end of the polymerization reaction, the stirring blades and the inner wall in the polymerization tank
No gel adhesion was observed.

(Comparative Example 1) Polymerization was carried out in the same manner as in Example 1 except that water was not added in the form of steam but in the form of an ordinary liquid. In some cases, considerable gel adhesion was observed in the aging tank and the polymerization tank. The gel content of the obtained polybutadiene was 0.6%.

[0039]

According to the present invention, polybutadiene having a low gel content can be produced. Further, the gel does not adhere to the stirring blade or the inner wall of the polymerization tank, and the polymerization can be stably performed for a long time.

 ────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Yoshio Nishimura 8-1 Goi south coast, Ichihara City, Chiba Prefecture Ube Industries, Ltd. Chiba Petrochemical Plant F term (reference) 4J011 AA05 EA02 EA09 HA03 HB22 HB24 HB26 4J028 AA01A AB00A AC47A AC48A BA00A BA01B BB00A BB01B BC15B BC16B BC17B BC19B BC25B CA14A CA17B CA32C CA44A FA07 4J100 AS02P CA01 CA15 FA03 FA09 FA12 FA19 FA27

Claims (4)

[Claims] Claims: 1. An inert organic solvent in the presence of a polymerization catalyst,
In a method for producing polybutadiene by polymerizing 1,3-butadiene, adding and mixing necessary moisture in a steam and / or hot water state to an inert solvent or a solution of 1,3-butadiene in an inert organic solvent. A method for producing polybutadiene, comprising: 2. The polymerization catalyst comprising: (A) a cobalt compound;
(B) R^Two _3-nAlX _n (Where R^Two Has 1 to 10 carbon atoms
A hydrocarbon group, X represents a halogen, and n is a number of 1-2.
You. A) a halogen-containing aluminum compound represented by the formula
And (C) a catalyst comprising water.
2. The method for producing polybutadiene according to 1. 3. An inert solvent or a solution of 1,3-butadiene in an inert organic solvent is mixed with necessary water, a halogen-containing aluminum compound is added, the mixture is aged, and a cobalt compound is added to polymerize. The method for producing polybutadiene according to claim 2, wherein 4. The method for producing polybutadiene according to claim 1, wherein the polybutadiene is cis-1,4-polybutadiene having a cis-1,4 structure of 80% or more.