JPH11181026A - Polybutadiene and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a polybutadiene comprising a specific high molecular weight polybutadiene and a specified low molecular weight polybutadiene, and further to provide a method for producing the polybutadiene in high polymerization activity. SOLUTION: This polybutadiene is the one having >=80% content of cis-1,4- structure and comprises following components A and B: (A) the polybutadiene having 700,000-3,000,000 weight average molecular weight(Mw) measured by a gel permeation chromatography(GPC) and produced by using a catalyst system comprising a cobalt compound, a nickel compound and an organoaluminum compound [the molar ratio of the cobalt compound to the nickel compound is regulated so as to be 1:(0.01-1)]; (B) the polybutadiene having 5,000-7,000 weight average molecular weight(Mw) measured by the GPC and produced by using the catalyst system comprising the nickel compound and the organoaluminum compound.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a bimodal polybutadiene comprising a mixture of a high molecular weight polybutadiene component and a low molecular weight polybutadiene component, and a method for producing the same.

[0002]

2. Description of the Related Art As a polybutadiene for impact-resistant polystyrene compositions, bimodality comprising a mixture of a high molecular weight polybutadiene component and a low molecular weight polybutadiene component is known.

Japanese Patent Application Laid-Open No. Sho 62-179542 discloses that a high molecular weight polybutadiene having an intrinsic viscosity [η] of 3.0 to 6.0 and a polybutadiene having a cis-1,4-structure as a main component is 70 to 30% by weight. % And an intrinsic viscosity [η] of 0.6 to
Disclosed is a polybutadiene rubber composition suitable as a rubber component of an impact-resistant polystyrene resin comprising 30 to 70% by weight of a low molecular weight polybutadiene having a polybutadiene having a cis-1,4-structure of 1.4 as a main component. I have. As a production method, a method comprising adding cyclooctadiene as a molecular weight regulator to a catalyst comprising a cobalt compound, an organoaluminum halide and water to produce a low molecular weight polybutadiene alone and blending it with a separately polymerized high molecular weight polybutadiene. Is described.

Japanese Patent Application Laid-Open No. 4-100810 discloses that the intrinsic viscosity [η] is 3.0 to 7.0 and cis-1,
4-80% to 30% by weight of a high molecular weight polybutadiene containing polybutadiene having a structure ratio of 80% or more, an intrinsic viscosity [η] of 0.5 to 1.4 and a cis-1,4-structure ratio of 80% A polybutadiene rubber composition suitable as a rubber component of an impact-resistant polystyrene resin comprising 30 to 70% by weight of a low molecular weight polybutadiene containing less than 10% by weight of polybutadiene as a main component is disclosed. As a production method, a high molecular weight polybutadiene is produced using cobalt octanoate, diethylaluminum, cyclooctadiene as a chain transfer agent in a catalyst comprising water, and a low molecular weight polybutadiene is produced using n-butyllithium as a catalyst. A solution blending method is described.

Japanese Patent Publication No. 42-9017 discloses 70 to 95% by weight of a high molecular weight polybutadiene having an intrinsic viscosity [η] of 1.5 to 20 and a cis-1,4-structure ratio of 85% or more. A rubber composition comprising 30 to 5% by weight of a low molecular weight polybutadiene having an intrinsic viscosity [η] of 0.35 to 0.75 is disclosed. As a production method, a method is described in which a low molecular weight polybutadiene is produced by homopolymerization using a cobalt compound-sesquialuminum catalyst, and a separately polymerized high molecular weight polybutadiene is blended.

Further, Japanese Patent Publication No. 43-628 discloses a method for polymerizing butadiene using a catalyst system in which a part of a cobalt salt is replaced in a catalyst system of a cobalt salt + aluminum dialkyl halide + water. .

[0007]

An object of the present invention is to provide a polybutadiene comprising a specific high molecular weight polybutadiene and a specific low molecular weight polybutadiene, and a method for producing the polybutadiene with high polymerization activity.

[0008]

SUMMARY OF THE INVENTION The present invention provides a cis-1,4-
It relates to a polybutadiene having a structure content of 80% or more and comprising the following components (A) and (B). (A) Gel permeation chromatograph (GPC)
Has a weight-average molecular weight (Mw) of 700,000 to 3,000,000, and a catalyst system comprising a cobalt compound, a nickel compound, and an organoaluminum compound (cobalt compound: nickel compound = 1: 0.01 to 1 (molar ratio) )). (B) Gel permeation chromatograph (GPC)
A polybutadiene having a weight-average molecular weight (Mw) of 5,000 to 70,000 as measured by a catalyst system comprising a nickel compound and an organoaluminum compound.

The present invention also relates to a method for producing polybutadiene having a cis-1,4-structure content of 80% or more and comprising the following components (A) and (B): Weight average molecular weight (Mw) measured by gel permeation chromatography (GPC) using a catalyst system (but a cobalt compound: nickel compound = 1: 0.01 to 1 (molar ratio)) comprising 700,000 to 3,000,000 polybutadiene (A) was produced, and the weight average molecular weight (M) measured by gel permeation chromatography (GPC) using a catalyst system comprising a nickel compound and an organoaluminum compound
w) producing 5,000 to 70,000 polybutadiene (B).

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The polybutadiene obtained in the present invention has a weight average molecular weight (Mw) of 700,000 to 3,000,000, preferably 1,000,000 to 3, as measured by gel permeation chromatography (GPC) of the component (A). 2 million.

The polybutadiene (B) obtained by the present invention
Gel Permeation Chromatograph (GPC)
Is 5,000 to 70,000, preferably 5,000 to 60,000, particularly preferably 5,000 to less than 30,000, and particularly preferably 5,000 to 2,000.
It is 50,000, still more preferably 10,000 to 25,000.

The polybutadiene of the present invention comprising the above components (A) and (B) has a cis-1,4-structure content of:
It is preferably at least 85%, more preferably at least 90%.

In the present invention, the method for producing the polybutadiene comprising the above components (A) and (B) is not particularly limited. (1) Two-stage tandem polymerization, for example, when the component (A) is used in the first tank, A method of producing the component (B) in the final tank, or a method of producing the component (B) in the first tank and producing the component (A) in the final tank. (2) One-stage polymerization, for example, (A) ) The method of producing the component and subsequently producing the component (B) in one vessel, or the method of producing the component (B) and subsequently producing the component (A) in one vessel, (3) Two-stage parallel Polymerization, for example, a method in which the components (A) and (B) are manufactured in separate tanks and then mixed. (4) The components (A) and (B) are separately manufactured, and then solution blending and melt blending are performed. And the like. Among them, two-stage tandem polymerization in which the component (A) is produced in the first polymerization step and then the component (B) is produced in the second polymerization step is preferred.

The catalyst system for producing polybutadiene (A) is a catalyst system comprising a cobalt compound, a nickel compound and an organoaluminum compound (however, cobalt compound: nickel compound = 1: 0.01 to 1 (molar ratio)). .
The catalyst system for producing polybutadiene (B) is a catalyst system comprising a nickel compound and an organoaluminum compound.

The catalyst system for producing polybutadiene (A) and the polymerization conditions include the following.

As the cobalt compound, 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, cobalt malonate, and bisacetylacetonate, trisacetylacetonate, and ethyl acetoacetate of cobalt. Organic base complexes such as triarylphosphine complexes of ester cobalt and cobalt halide, trialkylphosphine complexes, pyridine complexes and picoline complexes, and ethyl alcohol complexes.

Of these, cobalt octylate, cobalt naphthenate, cobalt bisacetylacetonate and trisacetylacetonate are preferred.

Examples of the nickel compound include an organic acid salt such as nickel naphthenate, nickel formate, nickel octylate, nickel stearate, nickel citrate, nickel benzoate, nickel toluate, and an organic complex compound such as nickel acetylacetonate; Nickel alkylbenzene sulfonate, nickel oxyborate and the like can be mentioned.

Among them, nickel octylate is preferred.

Examples of the organic aluminum compound include a halogen-containing aluminum compound, a trialkylaluminum compound, and an aluminoxane compound obtained by reacting them with water.

As the halogen-containing aluminum compound,
Examples thereof include dialkylaluminum halides such as dialkylaluminum chloride and dialkylaluminum bromide, alkylaluminum sesquichlorides such as alkylaluminum sesquibromide, and alkylaluminum dihalides such as alkylaluminum dichloride and alkylaluminum dibromide.

Specific examples of the compound include diethylaluminum monochloride, diethylaluminum monobromide, dibutylaluminum monochloride, ethylaluminum sesquichloride, ethylaluminum dichloride, dicyclohexylaluminum monochloride, diphenylaluminum monochloride and the like.

Examples of the trialkylaluminum compound include triethylaluminum, trimethylaluminum, triisobutylaluminum, trihexylaluminum, trioctylaluminum and the like.
Examples of the aluminoxane compounds include aluminoxanes obtained by reacting the above-mentioned halogen-containing aluminum and trialkylaluminum with water. These organoaluminum compounds may be used alone or in combination.

The amount of the cobalt compound used is butadiene 1
Usually, the cobalt compound is 5 × 10 ⁻⁷ to 1 ×
It is in the range of 10 ^-4 mol, preferably 5 × 10 ^-7 to 1 × 10 ^-5 mol.

The amount of the nickel compound used is as follows: cobalt compound: nickel compound = 1: 0.01 to 1, preferably
1: The range is from 0.05 to 0.5 (molar ratio).

The amount of the organoaluminum compound to be used is generally 10 to 5000 mol per 1 mol of the cobalt compound,
Preferably it is in the range of 50 to 1000 moles.

It is preferable to further add water to the above-mentioned catalyst component from the viewpoint of polymerization activity and the like. The amount of water used is usually 0.1 to 1 mol per mol of the organoaluminum compound.
1.2 mol, preferably 0.2 to 1.1 mol.

The order of addition of the catalyst components is not particularly limited.
In the step of producing polybutadiene (A), it is preferable to add water, an organoaluminum, a nickel compound, and a cobalt compound in this order, or to add the cobalt compound and the nickel compound simultaneously.

The polymerization method is not particularly limited.
Bulk polymerization using 1,3-butadiene itself as a polymerization solvent can be applied. Solvents for 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; hydrocarbon solvents such as mineral spirits, solvent naphtha and kerosene; and halogenated hydrocarbon solvents such as methylene chloride. .

The catalyst system for producing the polybutadiene (B) and the polymerization conditions include the following.

As the nickel compound, the same compounds as those used for producing the above-mentioned polybutadiene (A) can be used.

As the organoaluminum compound, those similar to those used for producing the above-mentioned polybutadiene (A) can be used.

The amount of the nickel compound used is in the range of 1 to 100, preferably 2 to 70 mol per mol of the cobalt compound.

The amount of the organoaluminum compound to be used is generally in the range of 0 to 200 mol, preferably 0 to 100 mol, per 1 mol of nickel.

The order of addition of the catalyst components is not particularly limited.
It is preferred to add the organoaluminum compound and then the nickel compound. In the case of performing continuous polymerization comprising a first polymerization step and a second polymerization step, a monomer may be additionally added to the second polymerization step.

The polymerization method is not particularly limited.
Bulk polymerization using 1,3-butadiene itself as a polymerization solvent can be applied. Solvents for 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; hydrocarbon solvents such as mineral spirits, solvent naphtha and kerosene; and halogenated hydrocarbon solvents such as methylene chloride. .

The ratio between the high molecular weight polybutadiene of the component (A) and the low molecular weight polybutadiene of the component (B) is
Component (A) is at least 30% by weight and less than 70% by weight, preferably at least 40% by weight and less than 70% by weight;
It is greater than 70% by weight, preferably greater than 30% by weight and less than 60% by weight. If the proportion of the component (A) is larger than the above range, the processability is reduced. If the proportion of the component (A) is smaller than the above range, the viscosity of the polybutadiene rubber composition is too small, which is not preferable.

[0038]

EXAMPLES Microstructure was performed by infrared absorption spectroscopy. Cis 1,4-740 cm ^-1 , transformer 1,
4-967 cm ^-1, was calculated microstructure from the absorption intensity ratio of 1,2-910 cm ^-1. The weight average molecular weight Mw, the number average molecular weight Mn, and the ratio Mw / Mn were determined by GPC using polystyrene as a standard substance. The ratio of the component (A) to the component (B) was calculated from the area ratio of the high molecular weight polybutadiene to the low molecular weight polybutadiene in the GPC chart.

Example 1 (1) Production of Component (A) (High Molecular Weight Polybutadiene) The inside of a 1.5 L autoclave was purged with nitrogen, and 20 wt% of butadiene, 35 wt% of benzene,
And 1 wt. Of a solution (138 g of butadiene) mixed with 45 wt% of 2-butene, and added at room temperature so that the concentration of water (H ₂ O) becomes 1.65 mmol / L, and the mixture was mixed at 700 rpm.
m for 30 minutes. Diethylaluminum chloride (DEAC) in cyclohexane (1 mol /
L) 3.3 mL was added and the mixture was stirred at room temperature for 5 minutes. The mixture was heated to 45 ° C., 0.6 mL of a toluene solution (0.005 mol / L) of nickel octylate (Ni (Oct) ₂ ) was added, and then cobalt octylate (Co (Oct) ₂ ) was added.
The polymerization was started by adding 1.4 mL of a toluene solution (0.005 mol / L), and the polymerization was carried out at 50 ° C. for 25 minutes.

(2) Production of Component (B) (Low Molecular Weight Polybutadiene) Next, 37 g (60 mL) of butadiene was added to the system under a pressure of 50 ° C., and then nickel octenoate (Co (Oc
t) 1.5 m of toluene solution of ₂ ) (0.1 mol / L)
L was added, heated and polymerized at 70 ° C. for 25 minutes, and 5 mL of an ethanol / heptane (1/1) solution containing an antioxidant was added to stop the polymerization. After releasing the pressure inside the autoclave, the polymerization liquid was poured into ethanol to recover polybutadiene. Next, the recovered polybutadiene was heated to 50 ° C.
For 6 hours under vacuum.

Examples 2 to 4 The amount of Ni (Oct) ₂ used in the production of the component (A) (high molecular weight polybutadiene) was changed as shown in Table 1,
Tables 3 and 4 show the results of polymerization in which the additional butadiene and Ni (Oct) ₂ in the production of the component (B) (low molecular weight polybutadiene) were changed as shown in Table 2.

Examples 5 to 6 After the production of the component (A) (high molecular weight polybutadiene) was completed, additional butadiene was added, and then Ni (Oc
t) In the same manner as in Example 2 except that the amount of ethyl aluminum sesquichloride (EASC) shown in Table 2 was added before adding ₂ ). The polymerization results are shown in Tables 3 and 4.

[0043]

[Table 1]

[0044]

[Table 2]

[0045]

[Table 3]

[0046]

[Table 4]

[0047]

According to the present invention, polybutadiene comprising a specific high molecular weight polybutadiene and a specific low molecular weight polybutadiene can be obtained with high activity.

Claims (2)

[Claims] 1. A polybutadiene having a cis-1,4-structure content of 80% or more and comprising the following components (A) and (B). (A) Gel permeation chromatograph (GPC)
Has a weight-average molecular weight (Mw) of 700,000 to 3,000,000, and a catalyst system comprising a cobalt compound, a nickel compound, and an organoaluminum compound (cobalt compound: nickel compound = 1: 0.01 to 1 (molar ratio) )). (B) Gel permeation chromatograph (GPC)
A polybutadiene having a weight-average molecular weight (Mw) of 5,000 to 70,000 measured by the method described above and produced using a catalyst system comprising a nickel compound and an organoaluminum compound. 2. A method for producing a polybutadiene having a cis-1,4-structure content of 80% or more and comprising the following components (A) and (B), comprising: a cobalt compound, a nickel compound and an organoaluminum compound. (But cobalt compound: nickel compound = 1: 0.0
1 (molar ratio)) and a weight average molecular weight (M) measured by gel permeation chromatography (GPC).
w) to produce a polybutadiene (A) having a molecular weight of 700,000 to 3,000,000, and a weight average molecular weight (Mw) of 5,000 measured by gel permeation chromatography (GPC) using a catalyst system comprising a nickel compound and an organoaluminum compound. ~
A method for producing polybutadiene, comprising producing 70,000 polybutadiene (B).