JPH10330428A - Production of polybutadiene - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a polybutadiene having a high content of cis-1,4 bonding, low in gel content and high in linearity. SOLUTION: This method for producing a polybutadiene is composed of a polymerization product of 1,3-butadiene by using a catalyst comprising (A) a cobalt compound, (B) a trialkylaluminum compound expressed by R<1> 3 Al (R<1> is a 1-10C hydrocarbon group), (C) a halogen-containing aluminum compound expressed by R<2> 3-n AlXn R<2> is a 1-10C hydrocarbon group, X is a halogen and (n) is a number of 1-2) and (D) water, in which (1) a ratio of the X atom in the component C to the Al atom in the components B and C: (X/Al) is 0.1-0.9 and (2) a molar ratio of the component D to the components (B+C) is 0.75-1.45.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing high cis-1,4-polybutadiene having a low gel content 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.

[0003] For example, in Canadian Patent No. 795860,
High cis-1,4-polybutadiene which polymerizes 1,3-butadiene in a solvent containing 20% or more of benzene by a catalyst consisting of a mixture of a hydrocarbylaluminum compound and water well mixed and aged, and cobalt dioctoate. 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. JP-B-61-54808 discloses that 1,3-butadiene is polymerized in a solvent comprising a linear or branched aliphatic hydrocarbon using a catalyst comprising diethylaluminum chloride, water and cobalt octoate. There is disclosed a method for causing this to occur. Japanese Patent Publication No. Sho 60-6362 discloses a method in which the addition of a small amount of an alkyl-substituted benzene to a polymerization solvent facilitates the control of polymerization and provides a substantially linear, gel-free high cis 1,4-polybutadiene. Have been.

Japanese Patent Application Laid-Open No. 7-188341 discloses a divalent cobalt salt, an alkylaluminum chloride, and a trialkylaluminum having 8 or more carbon atoms in a medium consisting of a solvent containing no aromatic compound and water. Discloses a method for polymerizing 1,3-butadiene using a catalyst comprising

However, in the polymerization of 1,3-butadiene, a double bond is contained in the polymer formed, so that a gel is easily formed especially when no aromatic solvent is contained, and the polymerization activity is low depending on the catalyst system. In some cases, improvements are desired.

Also, high cis-1,4-polybutadiene having a small degree of polymer chain branching (high linearity) has characteristics such as excellent abrasion resistance, heat resistance, and rebound resilience. ing. However, a solvent system containing no aromatic compound has a higher cis-1,4 compared to a solvent system containing an aromatic compound.
The degree of branching of the polymer chains of polybutadiene is increased.
Even in a solvent system containing no aromatic compound, there is a demand for a production method capable of obtaining high cis-1,4-polybutadiene having a small degree of branching.

[0008]

SUMMARY OF THE INVENTION The present invention provides a high cis-
An object of the present invention is to provide a method for producing polybutadiene having a 1,4 content, a low gel content, and a high linearity.

[0009]

SUMMARY OF THE INVENTION The present invention relates to (A) cobalt conversion
Compound, (B) R¹ _ThreeAl (where R is a carbonized carbon having 1 to 10 carbon atoms)
Shows a hydrogen group. Trialkyl aluminum represented by)
Compound, (C) R ^Two _3-nAlX_n(Where R^Two Is 1 carbon
~ 10 hydrocarbon groups, X represents halogen, and n represents 1-2
Is a number. Halogen-containing aluminum compound represented by)
(D) water and a catalyst comprising (1) component (C)
X atoms in the composition and Al atoms in the component (B) and the component (C)
(X / Al) is 0.1 to 0.9, and (2)
((B) component + (C) component) 1 mole of (D) component
1,3-butadiene using a catalyst having a
Production of polybutadiene characterized by polymerizing ene
About the method.

The present invention also provides (A) a cobalt compound,
(B) R ¹ ₃ Al (wherein, R represents. A hydrocarbon group having 1 to 10 carbon atoms) trialkyl aluminum compound represented _{^{by, (C) R 2 3-}} n AlX n ( wherein, R ² is carbon number 1-10
X represents a halogen, and n is a number of 1-2. A) a halogen-containing aluminum compound represented by the formula:
And (D) a catalyst obtained from water, wherein (1) the ratio (X / Al) of X atoms in component (C) to Al atoms in components (B) and (C) is 0.1 to 0.9. And (2)
(Component (B) + Component (C)) A method for producing polybutadiene, characterized in that 1,3-butadiene is polymerized using a catalyst in which component (D) is 0.75 to 1.45 mol per 1 mol. .

[0011]

DETAILED DESCRIPTION OF THE INVENTION As the cobalt compound (A), a salt or complex of cobalt is preferably used. Particularly preferred are cobalt salts such as cobalt chloride, cobalt bromide, cobalt nitrate, cobalt octylate, cobalt naphthenate, cobalt acetate and cobalt malonate, and bisacetylacetonate and trisacetylacetonate of cobalt. And organic base complexes such as triarylphosphine complex, trialkylphosphine complex, pyridine complex and picoline complex of ethyl acetoacetate cobalt and cobalt halide, and ethyl alcohol complex.

[0012] (B) (In the formula, R ¹ represents. A hydrocarbon group having 1 to 10 carbon atoms) R ¹ ₃ Al component as a trialkyl aluminum compound represented by, triethylaluminum, trimethylaluminum, tri Isobutylaluminum, trihexylaluminum, trioctylaluminum and the like.

[0013] Component (C) of R ² _3-n AlX n (wherein, R ²
Represents a hydrocarbon group having 1 to 10 carbon atoms, X represents halogen, n
Is a number from 1 to 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 diethyl aluminum monochloride, diethyl aluminum mono bromide,
Examples thereof include dibutylaluminum monochloride, ethylaluminum sesquichloride, ethylaluminum dichloride, dicyclohexylaluminum monochloride, and diphenylaluminum monochloride.

The amount of the cobalt compound (A) used is as follows:
Usually 1 × of cobalt compound is added to 1 mol of butadiene.
The range is 10 ^-7 to 1 × 10 ^-4 mol, preferably 1 × 10 ^-6 to 1 × 10 ^-5 mol.

The amount of the trialkylaluminum used as the component (B) is usually from 10 to 50 per mol of the cobalt compound.
00 mole, preferably in the range of 50-1000 moles.

The amount of the halogen-containing aluminum compound used as the component (C) is such that the ratio (X / Al) of X atoms in the component (C) to Al atoms in the components (B) and (C) is 0.1.
0.9, preferably 0.25 to 0.75.

The amount of water used as the component (D) is such that the amount of the component (D) is 0.75 to 1 mol per 1 mol of the component ((B) + the component (C)).
1.45 moles, preferably 0.8-1.2 moles.

The order of addition of the catalyst components is not particularly limited.
It is preferable that the component (B) and the component (C) are mixed and aged in an inert solvent before use. The aging time is preferably from 0.1 to 24 hours. The aging temperature is preferably from 0 to 80 ° C.

It is preferable to further add the component (D) to the aging solution of the components (B) and (C) for aging. The aging time is preferably from 0.1 to 24 hours. Aging temperature is 0
~ 80 ° C is preferred.

The polymerization method is not particularly limited.
Solution polymerization or the like can be applied. Examples of the solvent in the solution polymerization include aromatic hydrocarbons such as toluene, benzene, and xylene; aliphatic hydrocarbons such as n-hexane, butane, heptane, and pentane; alicyclic hydrocarbons such as cyclopentane and cyclohexane; Olefinic hydrocarbons such as -butene, cis-2-butene and trans-2-butene; mineral spirits, solvent naphtha, hydrocarbon solvents such as kerosene, and halogenated hydrocarbon solvents such as methylene chloride. . Also, 1,3-butadiene itself may be used as the polymerization solvent.

Among them, cyclohexane or a mixture of cis-2-butene and trans-2-butene is preferably used.

In the present invention, known molecular weight regulators 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.

The polymerization temperature is preferably in the range of -30 to 100 ° C, particularly preferably in the range of 30 to 80 ° C. Polymerization time is 10 minutes ~
A range of 12 hours is preferred, with 30 minutes to 6 hours being particularly preferred. 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, cis-1,4-structure-containing
Presence is 95% or more and the viscosity of toluene solution (T_cp) And 1
Mooney viscosity at 00 ° C (ML_{1 + 4}) Ratio (T_cp/ M
L _{1 + 4}) Is 2 or more and the gel content is 0.1 wt% or less.
The underlying polybutadiene can be produced.

The above T _cp / ML _{1 + 4} is high cis-1,4-
It is an index of the degree of branching of polybutadiene. T _cp indicates the degree of entanglement of molecules in a concentrated solution. For high cis-1,4-polybutadiene having a similar molecular weight distribution, if the molecular weight is the same (that is, ML _{1+ 4} as long as any) is greater the degree of branching index (T _cp identical degree of branching is made smaller). T _cp / ML _{1 + 4} is ML
_It is used as an index (the larger the _Tcp / ML1 _{+ 4} , the smaller the degree of branching) when comparing the degree of branching of _{1 + 4} different high cis-1,4-polybutadienes.

[0027]

EXAMPLES Microstructure was performed by infrared absorption spectroscopy. Cis 740 cm ^-1 , transformer 967 cm ^-1 , 1,2-
The microstructure was calculated from the absorption intensity ratio of 910 cm ^-1 . The molecular weight distribution is the ratio Mw / M of the weight average molecular weight Mw and the number average molecular weight Mn obtained from GPC using polystyrene as a standard substance.
It was evaluated by n.

The Mooney viscosity (ML _{1 + 4} ) is JIS K6300
It measured according to. The toluene solution viscosity (T _cp ) was determined by dissolving 2.28 g of the polymer in 50 ml of toluene, using a standard solution for calibration of a viscometer (JIS Z8809) as a standard solution, and using a Cannon-Fenske viscometer No. 400 as a standard solution. Measured at 25 ° C. The gel content was determined by dissolving about 5 g of the polymer in 200 mL of toluene, passing the solution through a 250-mesh wire mesh, washing the wire mesh thoroughly with toluene, and increasing the weight of the wire mesh after vacuum drying at 80 ° C for 5 hours. Calculated from minutes.

Example 1 The inside of a 50-mL flask was replaced with nitrogen, and 4.5 mL of a toluene solution (1 mol / L) of triethylaluminum (TEA) was used.
And stirred with a stirrer. Then, 1.5 mL of a cyclohexane solution (1 mol / L) of diethyl aluminum chloride (DEAC) was added, and the mixture was aged at room temperature for 30 minutes. The inside of an autoclave having a content of 1.5 L is replaced with nitrogen, 500 mL of cyclohexane and 155 g of butadiene are charged, and 700 rpm
With stirring. The temperature of the solution was room temperature. Then water (H ₂
O) 79.2μL, 1,5-cyclooctadiene (COD) in cyclohexane solution (3mol / L) 2.5mL as molecular weight regulator
Was added. 30 minutes later, the above aging solution ([Al] concentration = 1000mmo
1 / L) 4.8 mL was added. Five minutes later, the temperature of the solution was set to 65 ° C., and 1.5 mL of a cyclohexane solution (0.004 mol / L) of cobalt octenoate (Co (Oct) ₂ ) was added to initiate polymerization. After 30 minutes, 5.0 mL of an ethanol / heptane (1/1) solution containing an antioxidant was added to terminate the polymerization. Oh
After releasing the pressure inside the reactor, the polymerization solution was poured into ethanol to recover polybutadiene. Next, the recovered polybutadiene was vacuum dried at 50 ° C. for 6 hours. Tables 1 to 4 show polymerization conditions, aging conditions, polymerization results, and analysis results of the obtained polybutadiene.

Examples 2 to 6 The same procedures as in Example 1 were carried out except that the polymerization and aging conditions shown in Tables 1 and 2 were carried out. Table 1 shows the polymerization conditions, the aging conditions, the results of the polymerization and the results of analysis of the obtained polybutadiene.
The results are shown in Table 4.

Comparative Example 1 The interior of an autoclave having a content of 1.5 L was replaced with nitrogen, and 500 mL of cyclohexane and 155 g of butadiene were charged.
Stirred at 0 rpm. Next, 27 μL of H ₂ O and 2.5 mL of a cyclohexane solution of COD (3 mol / L) as a molecular weight regulator were added. 30 minutes later, diethyl aluminum chloride (DEA
2.4 mL of a toluene solution (1 mol / L) of C) was added. Five minutes later, the temperature of the solution was set to 65 ° C, and 1.5 mL of a Co (Oct) ₂ cyclohexane solution (0.004 mol / L) was added to initiate polymerization. After 30 minutes, 5.0 mL of an ethanol / heptane (1/1) solution containing an antioxidant was added to terminate the polymerization. Oh
After releasing the pressure inside the reactor, the polymerization solution was poured into ethanol to recover polybutadiene. Next, the recovered polybutadiene was vacuum dried at 50 ° C. for 6 hours. Table 1 shows the polymerization conditions, and Tables 3 and 4 show the results of polymerization and the results of analysis of the obtained polybutadiene.

Comparative Example 2 The procedure of Comparative Example 1 was repeated, except that the polymerization was performed under the polymerization conditions shown in Table 1. Tables 3 and 4 show the results of polymerization and the results of analysis of the obtained polybutadiene.

[0033]

[Table 1]

[0034]

[Table 2]

[0035]

[Table 3]

[0036]

[Table 4]

Example 7 The inside of a flask having a content of 50 ml was replaced with nitrogen, and 10 ml of a solution of triethylaluminum (TEA) in cyclohexane (1.0 mol / l) was added.
l was charged and stirred with a stirrer. Next, a solution of diethyl aluminum chloride (DEAC) in cyclohexane (1.0mo
(l / l) 10 ml and aged at room temperature for 30 minutes. Contents 1.5L
The inside of the autoclave is replaced with nitrogen, and cyclohexane
500 ml and 155 g of butadiene were charged and stirred at 700 rpm.
The temperature of the solution was room temperature. Then 48.6 μl of water (H ₂ O) (2.7 mmo
l), 1,5-cyclooctadiene (CO
2.5 ml of a cyclohexane solution (3.0 mol / l) of D) was added. Three
After 0 minute, 2.4 ml of the aging solution ([Al] = 1000 mmol / l) was added.
After 5 minutes, the temperature of the solution was raised to 65 ° C and cobalt octenoate (C
1.5 ml of a cyclohexane solution (0.004 mmol / l) of o (Oct) ₂ ) was added to initiate polymerization. After 30 minutes, 5.0 ml of an ethanol / heptane (1/1) solution containing an antioxidant was added to terminate the polymerization. After the internal pressure of the autoclave was released, the polymerization solution was charged into ethanol to recover polybutadiene. Next, the recovered polybutadiene was vacuum dried at 50 ° C. for 6 hours. The polymerization and aging conditions are shown in Tables 5 and 6, and the polymerization results and the analysis results of the obtained polybutadiene are shown in Tables 7 and 8.

Example 8 Except for carrying out the polymerization and aging conditions shown in Tables 5 and 6,
Performed in the same manner as in Example 7. Tables 7 and 8 show the results of polymerization and the results of analysis of the obtained polybutadiene.

Examples 9 and 10 The same procedures as in Example 7 were carried out except that the TEA was replaced with triisobutylaluminum (TIBA) and the polymerization and aging conditions shown in Tables 5 and 6 were used. Tables 7 and 8 show the results of polymerization and the results of analysis of the obtained polybutadiene.

Examples 11 to 13 The same procedures as in Example 7 were carried out except that TEA was replaced with trioctyl aluminum (TOA) and polymerization and aging conditions shown in Tables 5 and 6 were used. Tables 7 and 8 show the results of polymerization and the results of analysis of the obtained polybutadiene.

Examples 14 to 16 The same procedures as in Example 7 were carried out except that TEA was replaced by TIBA and DEAC was replaced by diisobutylaluminum chloride (DIBAC), and the polymerization and aging conditions shown in Tables 5 and 6 were used. Was. Tables 7 and 8 show the results of polymerization and the results of analysis of the obtained polybutadiene.

Examples 17 and 18 Cyclohexane was used as a polymerization solvent in cis-2-butene 6
8.6 wt%, trans-2-butene 17.1 wt%, cyclohexane
Example 7 was carried out in the same manner as in Example 7, except that the polymerization and aging conditions shown in Tables 5 and 6 were used instead of the mixed solvent consisting of 14.3 wt%. Tables 7 and 8 show the results of polymerization and the results of analysis of the obtained polybutadiene.

[0043]

[Table 5]

[0044]

[Table 6]

[0045]

[Table 7]

[0046]

[Table 8]

[0047]

The present invention provides a method for producing polybutadiene having a high cis-1,4 content, a low gel content and a high linearity.

Claims (2)

[Claims] 1. A (A) a cobalt compound, (B) R ¹ ₃ Al
(Wherein, R., Which represents a hydrocarbon group having 1 to 10 carbon atoms) trialkyl aluminum compound represented _{^{by, (C) R 2 3-}} n
AlX _n (wherein, R ² is a hydrocarbon group having 1 to 10 carbon atoms, X
Represents a halogen, and n is a number of 1-2. A) a catalyst comprising a halogen-containing aluminum compound represented by the formula (1) and (D) water, wherein (1) an X atom in the component (C);
The ratio (X / Al) of the component and the Al atom in the component (C) is
1,3-butadiene is polymerized using a catalyst in which component (D) is 0.75 to 1.45 moles per mole of (2) (component (B) + component (C)). A method for producing polybutadiene, comprising: Wherein (A) a cobalt compound, (B) R ¹ ₃ Al
(Wherein, R., Which represents a hydrocarbon group having 1 to 10 carbon atoms) trialkyl aluminum compound represented _{^{by, (C) R 2 3-}} n
AlX _n (wherein, R ² is a hydrocarbon group having 1 to 10 carbon atoms, X
Represents a halogen, and n is a number of 1-2. (D) a catalyst obtained from water, wherein (1) an X atom in the component (C),
The ratio (X / A) to the Al atom in the component (B) and the component (C)
l) is 0.1 to 0.9, and (2) (component (B) +
(Component (C)) The component (D) is used in an amount of 0.75 to 1.
A process for producing polybutadiene, comprising polymerizing 1,3-butadiene using a catalyst having a molar ratio of 45 mol.