JP2000178314A - Method for producing modified polybutadiene, and rubber composition - Google Patents

Abstract

(57) [Problem] To provide a rubber material having low rolling resistance and excellent wet skid resistance when used as a rubber material for automobile tires. SOLUTION: A 1,3-butadiene is converted to a cobalt-based catalyst composition comprising a cobalt compound, a halogen-containing organoaluminum compound, and water, or a nickel compound,
A method for producing a modified polybutadiene, comprising polymerizing in the presence of a nickel-based catalyst composition comprising an organoaluminum compound and a fluorine compound into polybutadiene, and then modifying the polybutadiene with a diamine compound.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a modified polybutadiene rubber particularly useful as a rubber material for a tire tread, a catalyst composition useful for producing the polybutadiene rubber, and a rubber material for a tire tread. It relates to a rubber composition that can be used.

[0002]

2. Description of the Related Art Polybutadiene and conjugated diene copolymer rubbers of butadiene-styrene copolymer rubbers have been used as rubbers for treads of automobile tires. In view of the demand for running stability, it has been desired to develop a rubber material having a small rolling resistance and a large road surface grip on snow and ice as a rubber for an automobile tire tread.

As a means for solving this problem, many methods have been proposed for introducing a specific atomic group into a polymer by, for example, reacting an alkali metal-containing diene polymer with a specific compound. .

[0004] JP-A-58-162604 and JP-A-59-117514 describe a method of modifying a rubber component by reacting it with benzophenone. JP-A-6-57769 and JP-B-6-78450 describe a method in which a rubber component is modified by reacting it with a nitroamino compound, a nitro compound or a nitroalkyl compound.

[0005] However, at present, it has not been possible to obtain a sufficiently satisfactory rubber material by these methods, and the cis-1,4 content in the polymer microstructure of the rubber material obtained by these methods is low. And the abrasion resistance is inferior to the high cis polymer. On the other hand, as a catalyst that gives a high cis polymer,
Co catalysts, Ni catalysts, Ti catalysts, Nd catalysts, and the like are known, but among these catalysts, Co catalysts, Ni catalysts, and Ti catalysts do not have a living property. Does not propose a method for producing a modified polymer.

A method for producing a modified polymer by adding a solvent to a high cis polymer, dissolving the solution, and bringing a catalyst and a modifier into contact with the solution is already known. For example, JP
JP-A-8-142901 discloses that a rubber is dissolved in a solvent, and a rubber having an unsaturated bond is reacted with an organic compound having a carboxyl group and an aldehyde group in the presence of an acid catalyst.
Methods for modifying rubber have been proposed. See also
JP-A-8-162602 also proposes a method in which a rubber is dissolved in a solvent and a rubber having an unsaturated bond is reacted with an organic compound having a carboxyl group and a salt of an aromatic sulfone halamide.

Japanese Patent Application Laid-Open No. Sho 61-225202 describes a method in which a rubber having an unsaturated bond is dissolved in a solvent, and benzylidenebutylamine or an organic acid halide is reacted in the presence of a Lewis acid to modify the rubber. Have been. All of these methods require a step of forming a rubber solution in which rubber is dissolved with a solvent, and thus require a large amount of solvent. Therefore, it has been desired to develop a method for obtaining a modified rubber having a high cis content by saving such a complicated operation by directly adding a modifying agent to the polymerization system.

As this method, a method has been proposed in which a modifier is directly added to a conjugated diene polymer produced by an Nd catalyst having pseudo-living properties. For example, JP-A-63-178102 discloses a method of producing a modified conjugated diene-based polymer by polymerizing a conjugated diene with a lanthanum series rare earth metal catalyst and reacting a polymer immediately after the polymerization with a specific organic metal halide. A method is described. JP-A-63-297403 discloses that a conjugated diene is polymerized with a lanthanum series rare earth metal catalyst, and the polymer immediately after the polymerization is reacted with a specific heterocumulene compound or a hetero three-membered ring compound to form a modified conjugate. A method for producing a diene polymer has been proposed. JP-A-63-305101 discloses a method similar to that described above in which 2,4,6-trichloro-1,2
A method for producing a modified conjugated diene polymer by adding a specific halogen compound such as 3,5-triazine is described.

[0009]

However, the polymerization reaction of a conjugated diene using a lanthanum series rare earth metal catalyst has a disadvantage that the polymerization reaction rate per unit catalyst amount is lower than that of a Co catalyst or a Ni catalyst. , Co catalyst and N
It has been considered that it is impossible to carry out the same modification reaction with the i catalyst as in the case of the lanthanum series rare earth metal catalyst, because the Co catalyst and the Ni catalyst do not have a living property or a pseudo-living property.

[0010]

Means for Solving the Problems Accordingly, the present inventors have:
Considering the possibility of introducing a modifying agent into a rubber having an unsaturated bond by producing a high-cis structure polybutadiene rubber with high activity and adding a modifying agent immediately after polymerization, we have earnestly based on this idea. As a result of the research, a cobalt-based catalyst composition (a composition containing a cobalt compound, a halogen-containing organoaluminum compound and water as active ingredients) or a nickel-based catalyst composition (containing a nickel compound, an organoaluminum compound and a fluorine compound as active ingredients) A specific diamine compound as a modifier to a polybutadiene immediately after polymerization obtained by polymerizing 1,3-butadiene in the presence of (composition), a modified polybutadiene having excellent properties can be produced. And arrived at the present invention.

Accordingly, the present invention provides a cobalt catalyst composition comprising a cobalt compound, a halogen-containing organoaluminum compound and water, or a nickel catalyst comprising a nickel compound, an organoaluminum compound and a fluorine compound. A method for producing a modified polybutadiene, comprising polymerizing in the presence of a catalyst composition to form polybutadiene, and then modifying the polybutadiene with a diamine compound.

[0012] The present invention also relates to a modified polybutadiene obtained by the above production method, wherein at least 10 parts of the modified polybutadiene are contained in the rubber component.
There is also a rubber composition characterized by containing by weight.

The catalyst composition used in the method for producing a modified polybutadiene according to the present invention is preferably a cobalt-based catalyst composition.
All amounts per mol of 1,3-butadiene are 1 × 10 ⁻⁷ to 1 × 10 ⁻³ mol for the cobalt compound and 1 × 10 ⁻³ mol for the halogen-containing organoaluminum compound.
× 10 ^-5 to 1 × 10 ^-1 mol, and 1 for water
Desirably, it is from × 10 ^-5 to 1 × 10 ^-1 mol.

In the method for producing a modified polybutadiene of the present invention, a nickel-based catalyst composition can be used instead of a cobalt-based catalyst composition as a catalyst composition. 1 × 10 ⁻⁷ for the nickel compound per mole of 1,3-butadiene
１1 × 10 ^-3 mol, 1 × 10 ^-5 to 1 × 10 ^-1 mol for the organoaluminum compound (organoaluminum compound containing no halogen atom) component, and 1 × 10 ^-4 for the fluorine compound. It is preferably from 1 to 1 mol.

In the present invention, the cobalt compound is preferably a cobalt salt of a carboxylic acid having 1 to 18 carbon atoms, and the halogen-containing organoaluminum compound is a dialkylaluminum halide having a total of 2 to 10 carbon atoms. , Alkyl aluminum dihalide,
Alternatively, it is preferably an alkyl aluminum sesquihalide. As the diamine compound, the number of carbon atoms is 2
It is preferable to use from 6 to 6 diaminoalkanes.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Next, the method for producing the modified polybutadiene rubber of the present invention, a catalyst composition useful for producing the polybutadiene rubber, and the use of the modified polybutadiene rubber as a rubber material for tire tread will be described in more detail. explain.

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

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 a cobalt-based catalyst composition is used, the halogen-containing organoaluminum compound may be R _3-n Al
X _n (where R is a hydrocarbon group having 1 to 10 carbon atoms, X
Represents a halogen, and n is an integer of 1 to 2. )) Can be mentioned. Examples thereof include dialkyl aluminum chloride, dialkyl aluminum halide such as dialkyl aluminum bromide, alkyl aluminum sesquichloride, alkyl aluminum sesquihalide such as alkyl aluminum sesquibromide, alkyl aluminum dichloride, and alkyl aluminum dibromide such as alkyl aluminum dibromide. No. Specific compounds include diethylaluminum monochloride, diethylaluminum monobromide, dibutylaluminum monochloride, ethylaluminum sesquichloride, ethylaluminum dichloride, dicyclohexylaluminum monochloride, diphenylaluminum monochloride and the like.

As the organoaluminum compound when a nickel-based catalyst composition is used, a trialkylaluminum represented by AlR ₃ (R represents a hydrocarbon group having 1 to 10 carbon atoms) can also be preferably used. Examples of such trialkylaluminums include trimethylaluminum, triethylaluminum, tri-aluminum.
n-propyl aluminum, triisopropyl aluminum, tri-n-butyl aluminum, triisobutyl aluminum, tripentyl aluminum, trihexyl aluminum, tricyclohexyl aluminum, trioctyl aluminum, triphenyl aluminum,
Tri-p-tolyl aluminum and tribenzyl aluminum can be mentioned. 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 a 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.

The catalyst composition used in the method for producing a polybutadiene rubber of the present invention is preferably a cobalt-based catalyst composition.
The cobalt compound is 1 × 10 ⁻⁷ to 1 × 10 ⁻³ mol per mol of 1,3-butadiene as the raw material monomer, and the amount of the halogen-containing organoaluminum compound is 1 × 10 ⁻⁷ mol per mol of the cobalt compound. ^-5 to 1 × 10 ^-1 mol, and the amount of water used is 1 to 1 mol of the cobalt compound.
It is from × 10 ^-5 to 1 × 10 ^-1 mol.

The order of adding the catalyst components to the reaction system is not limited. Each catalyst component can be added simultaneously or in any order.

There is no particular limitation on the polymerization method, and polymerization methods generally used for 1,3-butadiene, such as bulk polymerization and solution polymerization, can be used. 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, trans-2-butene, mineral spirits, solvent naphtha, kerosene and the like; and hydrocarbon solvents such as methylene chloride and the like can be used. it can. Further, 1,3-butadiene itself may be used as a polymerization solvent. Among them, benzene, cyclohexane, a mixture of cis-2-butene and trans-2-butene, and the like are suitably used as a solvent for solution polymerization.

In the present invention, when carrying out the polymerization reaction, known molecular weight regulators, for example, non-conjugated dienes such as cyclooctadiene and arene, or α-olefins such as ethylene, propylene and butene-1 Can be used.

The polymerization temperature is preferably in the range of -30 to 100.degree. C., particularly preferably in the range of 30 to 80.degree. 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 atmospheres (gauge pressure). In the production of the modified polybutadiene of the present invention, after a 1,3-butadiene is polymerized at a predetermined temperature for a predetermined time, a specific diamine-based compound is immediately added as a modifier to carry out a modification reaction.

As the modifier, a diamine compound, in particular, an aliphatic nitrogen-containing compound having two amino groups is used. Specifically, ethylenediamine, trimethylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, 1,2-diaminoethane, 1,2-propanediamine, 1,3-propanediamine, 1,4-diaminobutane , 2,7-diaminoheptane, 1,6-diaminohexane, 1,8-diaminooctane, 1.9-diaminononane, 1,10-diaminodecane and 1,12-diaminododecane. These modifiers may be used alone or in combination of two or more.

The denaturation temperature is preferably in the range of 0 to 100 ° C, more preferably in the range of room temperature to 70 ° C. If the temperature is too low, the progress of the modification reaction is slow, and if the temperature is too high, the polymer gels, which is not preferable. Usually, it is preferable to carry out the modification reaction at the same temperature as the polymerization temperature. The denaturation time is not particularly limited, but is usually preferably in the range of 0.5 to 6 hours. If the denaturation time is too short, the reaction does not proceed sufficiently, and if the denaturation time is too long, the polymer may gel, which is not preferable.

The amount of the modifier used is 0.01 to 100 g per 100 g of the produced polybutadiene (polybutadiene rubber).
It is 100 mmol, preferably 0.1 to 70 mmol, more preferably 0.2 to 30 mmol. When the amount of the modifying agent is small, the amount of the nitrogen element introduced into the modified polybutadiene is small, and the modifying effect is small. Also, if the amount is too large, the unreacted modifier tends to remain in the polybutadiene, and it takes time to remove the modifier.
Not preferred. In addition, it is preferable that the Mooney viscosity of the modified product is increased by one or more as compared with that before the modification.

Also, immediately after the polymerization of 1,3-butadiene,
Prior to the addition of the modifying agent, an aluminum halide or an alkyl halide (the alkyl group has 1 to 6 carbon atoms) may be added as a catalyst in order to accelerate the progress of the modifying reaction. Examples of aluminum halides include aluminum chloride, aluminum bromide, and aluminum iodide. Examples of the alkyl halide include ethyl bromide, ethyl iodide, butyl chloride, butyl bromide, and butyl iodide. The amount of this catalyst to be used is 0.01 to 50 mmol, preferably 0.05 to 30 mmol, more preferably 0.1 to 20 mmol, per 100 g of polybutadiene.

The modified polybutadiene rubber obtained according to the present invention is blended alone or blended with another synthetic rubber or natural rubber, and if necessary, oil-extended with a process oil, and then a filler such as carbon black is added. It is vulcanized by adding a vulcanizing agent, a vulcanization accelerator and other usual compounding agents, and is used for rubber applications requiring mechanical properties and abrasion resistance such as tires, hoses, belts and other various industrial products. . It can also be used as a plastic modifier.

When the modified polybutadiene rubber obtained by the present invention is used as a rubber material for an automobile tire tread, at least 10% by weight is contained in the rubber component in a rubber composition comprising a rubber component and a compounding agent. It is preferable to be blended.

[0033]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Examples, but these do not limit the purpose of the present invention. The rubbery polymers obtained in the following Examples and Comparative Examples have Mooney viscosities (ML _{1 + 4} , 100
C), cis-1,4-structure amount, nitrogen content, and gel fraction were measured by the following methods.

(1) Mooney viscosity (ML _{1 + 4} , 100
° C): 100 according to JIS-K6300 using a Mooney viscometer (SMV-200) manufactured by Shimadzu Corporation.
After preheating at 1 ° C. for 1 minute, the viscosity was measured for 4 minutes and indicated as the Mooney viscosity of the rubber (ML _{1 + 4} , 100 ° C.). (2) Cis-1,4-structure amount: The microstructure of the polymer was measured by a 0.4% by weight carbon disulfide solution by infrared absorption spectrum analysis to calculate the cis-1,4-structure amount. did. (3) Nitrogen content: Quantified by the Kjeldahl method according to JIS-K0102.

(4) Method for measuring gel fraction: About 0.5 g of an unvulcanized rubber sample is taken, cut into small pieces, and accurately weighed (Rg). The weight of a 100 mesh stainless steel basket is precisely weighed (Kg), and the weighed sample is entirely transferred to the basket.
Measure the weight (Rg + Kg). This is toluene 100
Immerse in a bottle with a cap containing mL and leave at 23 ° C. for 24 hours. Then, the basket is pulled up, dried at 23 ° C. for 24 hours, further dried under reduced pressure at 70 ° C. for 24 hours to a constant weight, and the toluene-insoluble matter is accurately weighed together with the basket (Gg + Kg). The gel fraction was determined.

Gel fraction (%) = 100 × [G− (R ×
(Filler parts ÷ rubber composition total parts)] ÷ [(R ×
(Parts by weight of rubber: total parts by weight of rubber composition)] However, parts by weight of filler: parts by weight of carbon black in Table 1 Total parts by weight of rubber composition: total parts by weight of all components in Table 1 Parts by weight of rubber: The rubber components (NR + BR or modified B
R) total weight parts

Further, 300% elastic modulus, rolling resistance index,
The tensile strength and wet skid resistance index were measured by the following methods. (1) 300% modulus (M _300): JIS-K6301
And a modulus at 300%. (2) Rolling resistance index: Using a viscoelastic spectrometer VES manufactured by Iwamoto Seisakusho, tan δ was measured at a temperature of 70 ° C., an initial distortion of 10%, and a dynamic strain of 2%, and the rolling resistance was calculated by the following equation. An index was determined. A larger index value indicates a lower rolling resistance, and the rolling resistance may be 100 or more.

Rolling resistance index = 100 × [(value of comparative example (unmodified product)) / (value of example (modified product)]]

(3) Tensile strength: Measured according to JIS-K-6301. (4) Wet skid resistance index: ASTM-E303- using a portable skid resistance meter manufactured by Stanley.
83. Indices of grip characteristics (driving performance, braking performance and steering performance) on a wet road surface indicate that the larger the value, the better.

[Example 1]
In a 5-liter stainless steel autoclave,
Benzene -C ₄ fraction mixed l of solution (benzene 26.9% by weight containing 1,3-butadiene 27.9 wt%, and a C ₄ fraction composed mainly of cis-2-butene 4
Then, 2 mmol of water and 2.9 mmol of diethylaluminum monochloride were added thereto, followed by stirring, and 4.24 mmol of cyclooctadiene was added. The temperature of the autoclave was raised, and after the internal temperature reached 58.5 ° C., cobalt octoate 0.0087
Then, the polymerization reaction was carried out at 60 ° C. for 30 minutes. Immediately after the completion of the polymerization reaction, at 78C, 1.78 mmol of 1,3-propanediamine was added as a modifier,
The denaturation reaction was performed at the same temperature for 120 minutes.

After completion of the reaction, unreacted gas is discharged out of the system,
500 ml of toluene was added to make a modified polybutadiene solution in toluene, and then methanol 500
After adding milliliter and stirring for 10 minutes, the stirring was stopped, the content of the autoclave was transferred to another 2 liter container, and the polymer (modified polybutadiene) was separated by filtration.
Next, after dissolving the polymer in 0.8 liter of toluene,
An operation of adding 0.8 liter of methanol to precipitate a polymer and repeating filtration and separation was repeated three times, and then Irganox 1010 [tetrakis- (methylene-3- (3,5-di-tert-butyl-4) was used as an antioxidant. -Hydroxyphenyl) propionate) methane] was added to the modified rubber at 0.11 phr, and tris (nonylphenyl) phosphite as an antioxidant was added at 0.45 phr, and kneaded. After drying, a modified polybutadiene was produced.

[Examples 2 and 3] As modifiers, 1,3-
Except that the addition amount of propanediamine was changed to 0.49 mmol (Example 2) or 1.25 mmol (Example 3), the same operation as in Example 1 was performed to obtain a modified polybutadiene.

Example 4 In carrying out the denaturation reaction,
A modified polybutadiene was produced in exactly the same manner as in Example 1 except that 20 mmol of aluminum chloride was used as a catalyst.

Example 5 A modified polybutadiene was produced in the same manner as in Example 1 except that 1.25 mmol of 1,2-diaminoethane was used instead of 1,3-propanediamine.

Example 6 A modified polybutadiene was produced in the same manner as in Example 1 except that 1.25 mmol of 1,4-diaminobutane was used instead of 1,3-propanediamine.

[Comparative Example 1] The same operation as in Example 1 was performed, and after polymerization of 1,3-butadiene was performed at 60 ° C for 30 minutes, the unreacted gas was immediately discharged without adding a modifier. After that, the same post-processing as in Example 1 is performed,
Unmodified polybutadiene was produced. A rubber composition was obtained according to the formulation shown in Table 1. The cis-1,4 content of the microstructure of the unmodified polybutadiene was 98.2%.

[Vulcanization properties] Polybutadiene rubber (modified BR or unmodified BR) obtained in each of Examples and Comparative Example 1
Was blended as shown in Table 1 to prepare a rubber composition. Next, the obtained blend was press-vulcanized at 150 ° C. for 30 minutes to obtain a cured product having a physical property of 30% by the above method.
The 0% elastic modulus, rolling resistance index, tensile strength, and wet skid resistance were measured and are shown in Table 2.

[0048]

[Table 1] Table 1 配 Mixing amount (parts by weight) ────────────── {Modified BR or BR 70 NR 30 carbon black (ISAF) 45 zinc white (ZnO) 3 stearic acid 1 vulcanization accelerator * 1 sulfur 1.5} ────────── * N-tert.-butyl-2-benzothiazolylsulfenamide

[0049]

Table 2 Table 2 Example Comparative Example 1 1 2 3 4 5 6 (Native) 量 Amount of denaturant (mmol) 1.78 0.49 1.25 1.78 1.25 1.25 0 Nitrogen content (ppm) 270 110 150 300 160 145 Not detected Mooney viscosity 34 35 36 34 35 36 33 Gel fraction (%) 39.8 36.8 37.8 39.4 38.0 37.5 33.6 cis-1,4 content (%) 98.2 98.3 98.2 98.2 98.3 98.2 98.2 ───────────────────────────────── 300% modulus (MPa) 11.78 11.09 12.06 12.60 12.12 12.02 10.27 Rolling resistance index 107 104 106 108 107 107 100 Tensile strength (MPa) 22.35 22.95 22.73 22.55 22.70 22.68 20.98 Wet skid index 108 106 107 108 107 106 100 ───────────────── ────────────────

[0050]

According to the present invention, 1,3-butadiene is converted to a cobalt-based catalyst composition comprising a cobalt compound, a halogen-containing organoaluminum compound and water, or a nickel-based catalyst composition comprising a nickel compound, an organoaluminum compound and a fluorine compound. After polymerization in the presence of the catalyst composition to form polybutadiene, the modified polybutadiene rubber produced by a method of modifying this polybutadiene with a diamine compound has an increased Mooney viscosity, an increased gel fraction, an increased tensile strength, and a rebound resilience. Rate (rolling resistance index)
And the wet skid resistance have been improved, and it is particularly useful as a material for automobile tires.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08L 15:00) (72) Inventor Tetsuji Nakajima 8-1, Goi Minamikaigan, Ichihara-shi, Chiba Ube Industries Co., Ltd. (72) Inventor Kiyoshige Muraoka 2-1-1 Tsutsui-machi, Chuo-ku, Kobe-shi, Hyogo Sumitomo Rubber Industries Co., Ltd. (72) Noriko Yagi 2, Tsutsui-cho, Chuo-ku, Kobe-shi, Hyogo 1-1 Term in Sumitomo Rubber Industries Co., Ltd. F-term (reference) 4J002 AC002 AC012 AC111 AE053 DA036 FD016 FD023 FD140 FD150 GN01 4J028 AA01A AB00A AC47A AC48A BA01B BB01B BC15B BC16B BC17B BC19B CA32C CB30C01CA01 CB94B01B02B FA08 FA18 FA19 HA61 HC46 JA29

Claims (6)

[Claims] 1. A 1,3-butadiene comprising a cobalt compound, a halogen-containing organoaluminum compound, and a cobalt-based catalyst composition comprising water or a nickel compound,
A method for producing a modified polybutadiene, comprising polymerizing in the presence of a nickel-based catalyst composition comprising an organoaluminum compound and a fluorine compound into polybutadiene, and then modifying the polybutadiene with a diamine compound. 2. The catalyst composition to be used is a cobalt-based catalyst composition, and the amount of the catalyst component used is 1,
For 1 mol of 3-butadiene, 1 × 10 ⁻⁷ to 1 × 10 ⁻³ mol for the cobalt compound and 1 × 10 ⁻⁵ to 1 × 1 for the halogen-containing organoaluminum compound.
0 ^-1 mol, and 1 × 10 ⁻⁵ to 1 × 1 for water.
2. The method for producing a modified polybutadiene according to claim 1, wherein the amount is 0 ^-1 mol. 3. The method according to claim 1, wherein the cobalt compound has 1 to 18 carbon atoms.
3. The method for producing a modified polybutadiene according to claim 1, wherein the salt is a cobalt salt of a carboxylic acid. 4. The modified polybutadiene according to claim 1, wherein the halogen-containing organoaluminum compound is a dialkylaluminum halide, alkylaluminum dihalide or alkylaluminum sesquihalide having a total of 2 to 10 carbon atoms. Production method. 5. The method for producing a modified polybutadiene according to claim 1, wherein the diamine compound is a diaminoalkane having 2 to 6 carbon atoms. 6. A rubber composition comprising at least 10% by weight of a modified polybutadiene obtained by the production method according to any one of claims 1 to 5 in a rubber component.