JPH10182726A - Catalyst and process for production of conjugated diene polymer using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a catalyst giving a conjugated diene polymer containing a reduced amount of gel, manifesting high linearity by compounding a cobalt compound, an ionic compound of a non-coordinating anion and a cationic compound and an organometallic compound of a specific element. SOLUTION: The catalyst useful for production of polymers of conjugated dienes such as butadiene, isoprene, etc., having high cis-1,4 content, reduced gel content and high linearity, is obtained by compounding (A) the cobalt compound (e.g. cobalt octenoate, etc.), (B) the ionic compound of the non- coordinating anion and the cationic compound [e.g. triphenyl- carboniumtetrakis-(pentafluorophenyl)borate, etc.] and (C) the organometallic compound of the elements (I-III) of the periodic table (e.g. triethylaluminum, etc.).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a novel cobalt-based catalyst and a method for producing a conjugated diene polymer using the catalyst.

[0002]

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

[0003] For example, in Canadian Patent No. 795860,
Mix the hydrocarbyl aluminum compound and water well,
A process is disclosed for producing high cis-1,4-polybutadiene by polymerizing an aged mixture of cobalt dioctoate and 1,3-butadiene in a solvent containing at least 20% benzene.

Japanese Patent Publication No. Sho 61-54808 discloses that 1,3-butadiene is dissolved in a solvent comprising a linear or branched aliphatic hydrocarbon using a catalyst comprising diethylaluminum chloride, water and cobalt octoate. A method of polymerizing is disclosed. Japanese Patent Application Laid-Open No. Hei 7-188341 discloses that a catalyst composed of a divalent cobalt salt, an alkylaluminum chloride, and two kinds of trialkylaluminum is used in a medium consisting of a solvent containing no aromatic compound and water. 3-
A method for polymerizing butadiene is disclosed.

[0005] Polym. Commun., Vol. 32, 514 (1991) discloses a method for polymerizing 1,3-butadiene using a catalyst comprising cobalt acetylacetonate and methylalumoxane.

EP 0667357A1 discloses a method for polymerizing 1,3-butadiene using a catalyst comprising a lanthanide salt, an alkylaluminum and a boron organometallic derivative.

However, in the polymerization of 1,3-butadiene, a gel is likely to be formed especially when an aromatic solvent is not contained because the formed polymer contains a double bond.
Further, depending on the catalyst system, the polymerization activity may be low, and improvement is desired.

[0008] Among the high cis-1,4-polybutadienes, those having a small degree of branching in the polymer chain have excellent properties such as abrasion resistance, heat resistance and rebound resilience. However, high cis synthesized in a solvent system that does not contain aromatic compounds
The degree of branching of -1,4-polybutadiene was larger than that of a solvent system containing an aromatic compound. Therefore, there is a need for a method of producing a high cis-1,4-polybutadiene having a small degree of branching in a solvent system containing no aromatic compound.

As an index of the degree of branching of high cis-1,4-polybutadiene, toluene solution viscosity (T _cp ) and Mooney viscosity (M
L _{1 + 4} ) (T _CP / ML _{1 + 4} ). T _CP indicates the degree of entanglement of molecules in a concentrated solution, and for high cis-1,4-polybutadiene having a similar molecular weight distribution, the same molecular weight (ie, 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
_When comparing the degree of branching of _{1 + 4} different high cis-1,4-polybutadiene, it is used as an index (the larger the _TCP / ML _{1 + 4} , the smaller the degree of branching).

[0010]

SUMMARY OF THE INVENTION A novel cobalt-based polymerization catalyst suitable as a conjugated diene polymerization catalyst, and a high cis-1,4 content, low gel content, and linear content using the catalyst. It is intended to provide a method for producing a conjugated diene having a high property.

[0011]

The present invention provides (A) a cobalt compound, (B) an ionic compound of a non-coordinating anion and a cation, and (C) an organic compound of an element of Groups I to III of the periodic table. It relates to a catalyst obtained from a metal compound.

The present invention also provides (A) a cobalt compound,
The present invention relates to a catalyst comprising (B) an ionic compound of a non-coordinating anion and a cation, and (C) an organometallic compound of an element from Groups I to III of the periodic table.

The present invention also relates to a method for producing a conjugated diene polymer, comprising polymerizing a conjugated diene compound using the above catalyst.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION As the cobalt compound (A) in the present invention, 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, trisacetylacetonate, and ethyl acetoacetate of cobalt. Examples thereof include triarylphosphine complexes and trialkylphosphine complexes of ester cobalt and cobalt halide, organic base complexes such as pyridine complexes and picoline complexes, and ethyl alcohol complexes.

The non-coordinating anion constituting the ionic compound of the non-coordinating anion and the cation of the component (B) of the present invention includes, for example, tetra (phenyl) borate, tetra (fluorophenyl) borate, tetrakis (Difluorophenyl) borate, tetrakis (trifluorophenyl) borate, tetrakis (tetrafluorophenyl) borate, tetrakis (pentafluorophenyl) borate, tetrakis (tetrafluoromethylphenyl) borate, tetra (triyl) borate, tetra (xylyl) borate , (Triphenyl, pentafluorophenyl) borate, [tris (pentafluorophenyl), phenyl] borate, tridecahydride-
7,8-dicarboundecaborate and the like.

On the other hand, examples of the cation include a carbonium cation, an oxonium cation, an ammonium cation, a phosphonium cation, a cycloheptyltrienyl cation, and a ferrocenium cation having a transition metal.

Specific examples of the carbonium cation include:
Examples include trisubstituted carbonium cations such as triphenylcarbonium cation and trisubstituted phenylcarbonium cation. Specific examples of the tri-substituted phenylcarbonium cation include tri (methylphenyl)
Examples thereof include a carbonium cation and a tri (dimethylphenyl) carbonium cation.

Specific examples of the ammonium cation include:
Trialkylammonium cations such as trimethylammonium cation, triethylammonium cation, tripropylammonium cation, tributylammonium cation, tri (n-butyl) ammonium cation, N, N-diethylanilinium cation, N, N-2,4,6 -
Examples thereof include N, N-dialkylanilinium cations such as pentamethylanilinium cation, dialkylammonium cations such as di (i-propyl) ammonium cation and dicyclohexylammonium cation.

Specific examples of the phosphonium cation include:
Examples include triarylphosphonium cations such as triphenylphosphonium cation, tri (methylphenyl) phosphonium cation, and tri (dimethylphenyl) phosphonium cation.

As the ionic compound, those arbitrarily selected and combined from the non-coordinating anions and cations exemplified above can be preferably used.

Among them, ionic compounds include triphenylcarbonium tetrakis (pentafluorophenyl) borate, triphenylcarbonium tetrakis (tetrafluorophenyl) borate, N, N-dimethylanilinium tetrakis (pentafluorophenyl) borate, 1,1′-dimethylferrocenium tetrakis (pentafluorophenyl) borate and the like are preferred.

The ionic compounds may be used alone or in combination of two or more.

As the component (C) of the present invention, Periodic Table I
As the organometallic compounds of Group III to III elements, compounds represented by the general formula R
_3-n AlX _n (R is a hydrocarbon group having 1 to 10 carbon atoms, X is a halogen radical, n is 0-1.) Trialkyl aluminum represented by organic aluminum compounds such as dialkylaluminum halide, Organic lithium compounds, organic magnesium compounds, organic zinc compounds, organic boron compounds and the like can be mentioned.

Specific examples of the trialkylaluminum compound include trimethylaluminum, triethylaluminum, trimethylaluminum, triisobutylaluminum, trihexylaluminum, trioctylaluminum, tridecylaluminum and the like. Further, methyllithium, butyllithium, phenyllithium, benzyllithium, neopentyllithium, trimethylsilylmethyllithium, bistrimethylsilylmethyllithium, dibutylmagnesium, dihexylmagnesium, diethylzinc, dimethylzinc, boron trifluoride, triphenylboron, etc. it can.

Further, ethyl magnesium chloride,
Organometallic halides such as butylmagnesium chloride, dimethylaluminum chloride, diethylaluminum chloride, sesquiethylaluminum chloride, ethylaluminum dichloride and the like, and hydrogenated organometallic compounds such as diethylaluminum hydride and sesquiethylaluminum hydride are also included. Further, two or more kinds of organometallic compounds can be used in combination. Among them, triethylaluminum and diethylaluminum chloride can be preferably used.

Although the mixing ratio of each catalyst component varies depending on various conditions, the molar ratio of the cobalt compound of component (A) to the non-coordinating anion of component (B) and the ionic compound of cation is preferably 1: 0.1 to 1:10, more preferably
1: 0.2 to 1: 5.

The molar ratio of the cobalt compound (A) to the organometallic compound (C) is preferably from 1: 0.1 to 1: 0.1.
The ratio is 1: 1000, more preferably 1: 1 to 1: 100.

The order of addition of the catalyst components is not particularly limited, but can be, for example, in the following order. The contact mixture obtained by adding the conjugated diene compound monomer to be polymerized, the component (C) and the component (B) in any order,
(A) Add the component. The component (B) and then the component (A) are added to a contact mixture of the conjugated diene compound monomer to be polymerized and the component (C). The component (A) and then the component (B) are added to a contact mixture of the conjugated diene compound monomer to be polymerized and the component (C).

The catalyst of the present invention and / or each component of the catalyst can be used by being supported on an inorganic compound or an organic polymer compound.

As the inorganic compound as the carrier, inorganic oxides, inorganic chlorides and inorganic hydroxides are preferable, and those containing small amounts of carbonates and sulfates can also be used. Particularly preferred are inorganic oxides, such as silica, alumina, magnesia, titania, zirconia, and calcia. These inorganic oxides have an average particle size of 5 to 15
Porous fine particles having a particle size of 0 μm and a specific surface area of 2 to 800 m ² / g are preferable, and can be used after being heat-treated at, for example, 100 to 800 ° C.

The organic polymer compound preferably has an aromatic ring, a substituted aromatic ring, or a functional group such as a hydroxy group, a carboxyl group, an ester group, or a halogen atom in the side chain. As specific examples, ethylene, propylene, α-olefin homopolymer having the functional group by chemical modification such as polybutene, α-olefin copolymer, acrylic acid, methacrylic acid, vinyl chloride, vinyl alcohol, styrene, homopolymer such as divinylbenzene, Copolymers and their chemically modified products can be mentioned. As these organic polymer compounds, spherical fine particles having an average particle diameter of 5 to 250 μm are used.

Here, the conjugated diene compound monomer to be polymerized may be a whole or a part. In the case of some of the monomers, the above contact mixture can be mixed with the remaining monomer or the remaining monomer solution.

As the conjugated diene compound monomer, 1,3-
Butadiene, isoprene, 1,3-pentadiene, 2-ethyl
Examples thereof include -1,3-butadiene, 2,3-dimethylbutadiene, 2-methylpentadiene, 4-methylpentadiene, and 2,4-hexadiene.

These monomer components may be used alone or in combination of two or more.

In addition to conjugated dienes, ethylene, propylene, butene-1, butene-2, isobutene, pentene-
Acyclic monoolefins such as 1,4-methylpentene-1, hexene-1, and octene-1, cyclopentene, cyclohexene, and cyclic monoolefins such as norbornene, and / or aromatic vinyl compounds such as styrene and α-methylstyrene; Non-conjugated diolefins such as dicyclopentadiene, 5-ethylidene-2-norbornene and 1,5-hexadiene may be contained in small amounts.

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; cycloaliphatic hydrocarbons such as cyclopentane and cyclohexane; -Butene, cis-2-butene, trans-2-
Examples thereof include hydrocarbon solvents such as olefin hydrocarbons such as butene, mineral spirit, solvent naphtha, and kerosene, and halogenated hydrocarbon solvents such as methylene chloride. Further, 1,3-butadiene itself may be used as the polymerization solvent.

Among them, cyclohexane or cis
A mixture of -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-1
Α-olefins 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 (gauge 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.

[0041]

EXAMPLES Microstructure was performed by infrared absorption spectroscopy. Cis 740 cm ^-1 , transformer 967 cm ^-1 , 1,
The microstructure was calculated from the absorption intensity ratio of 2-910 cm ^-1 .
The molecular weight distribution was determined using GP using polystyrene as a standard.
Ratio of weight average molecular weight Mw and number average molecular weight Mn obtained from C
Evaluated by Mw / Mn.

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

[0043]

【Example】

(Example 1) The inside of a 1.5 L autoclave was replaced with nitrogen, and 500 mL of cyclohexane (c-Hex) and 155 g of 1,3-butadiene (Bd) were charged. Next, a toluene solution of 0.30 mmol of triethylaluminum (TEA) as the component (C) and triphenylcarbonium tetrakis (pentafluorophenyl) borate (Ph ₃ CB (C
₆ F _{5) 4)} 0.012mmol cyclohexane solution, and the component (A) as cobalt octanoate (Co (Oct) ₂₎ 0.006mmol cyclohexane was added and polymerization was carried out for 30 minutes at 65 ° C.. After the polymerization, unreacted 1,3-butadiene was released from the autoclave, and an antioxidant was added. The polymerization solution was poured into ethanol to precipitate the polymer, which was washed, filtered and dried.
Table 1 shows the polymerization conditions, and Tables 2 and 3 show the polymerization results and the analysis results of the obtained polybutadiene.

(Examples 2 and 3) The same procedure as in Example 1 was performed except that the conditions shown in Table 1 were used. Tables 2 and 3 show the results of polymerization and the results of analysis of the obtained polybutadiene.

(Example 4) The procedure of Example 1 was repeated, except that triisobutylaluminum (TiBA) was used as the component (C) under the conditions shown in Table 1. Tables 2 and 3 show the results of polymerization and the results of analysis of the obtained polybutadiene.

Example 5 The same procedure as in Example 1 was carried out except that diethyl aluminum chloride (DEAC) was used as the component (C) under the conditions shown in Table 1. Table 2-3
Shows the results of polymerization and the results of analysis of the obtained polybutadiene.

Example 6 Example 4 was carried out in the same manner as in Example 4 except that the order of addition was changed and the conditions shown in Table 1 were used. Table 2
3 to 3 show the results of polymerization and the results of analysis of the obtained polybutadiene.

Example 7 After charging cyclohexane and 1,3-butadiene, 3.75 mmol of 1,5-cyclooctadiene (COD) was added as a molecular weight regulator, and the procedure was carried out under the conditions shown in Table 1. And in the same manner as in Example 6. Tables 2 and 3 show the results of polymerization and the results of analysis of the obtained polybutadiene.

Comparative Example 1 The procedure of Example 1 was repeated, except that the component (B) was not used and the conditions were as shown in Table 1. Tables 2 and 3 show the results of polymerization and the results of analysis of the obtained polybutadiene.

Comparative Example 2 The procedure of Example 5 was repeated, except that the component (B) was not used and the conditions were as shown in Table 1. Tables 2 and 3 show the results of polymerization and the results of analysis of the obtained polybutadiene.

Comparative Example 3 The inside of an autoclave having a capacity of 1.5 L was replaced with nitrogen, and cyclohexane and 1,3-butadiene were charged.
_A solution of 2 mmol of 2O) and 7.5 mmol of COD in cyclohexane was added. 30 minutes later, DEAC 2.4 mmol toluene solution,
Co (Oct) ₂ 0.006 mmol cyclohexane solution was added,
Polymerization was performed at 65 ° C. for 30 minutes. After the polymerization, unreacted 1,3-butadiene was released from the autoclave, and an antioxidant was added. The polymerization solution was poured into ethanol to precipitate the polymer,
Washed, filtered and dried. Table 1 shows the polymerization conditions, and Tables 2 and 3 show the polymerization results and the analysis results of the obtained polybutadiene.

Comparative Example 4 An experiment was performed in the same manner as in Comparative Example 3 except that the experiment was performed under the conditions shown in Table 1. Tables 2 and 3 show the results of polymerization and the results of analysis of the obtained polybutadiene.

[0053]

[Table 1]

[0054]

[Table 2]

[0055]

[Table 3]

[0056]

Industrial Applicability A novel cobalt-based polymerization catalyst suitable as a conjugated diene polymerization catalyst, and a high cis-1,4 content, a low gel content, and a high linearity using the catalyst. Provided is a method for producing a conjugated diene.

Claims (3)

[Claims] 1. A catalyst obtained from (A) a cobalt compound, (B) an ionic compound of a non-coordinating anion and a cation, and (C) an organometallic compound of an element from Groups I to III of the periodic table. 2. A catalyst comprising (A) a cobalt compound, (B) an ionic compound of a non-coordinating anion and a cation, and (C) an organometallic compound of an element from Groups I to III of the periodic table. 3. A method for producing a conjugated diene polymer, comprising polymerizing a conjugated diene compound using the catalyst according to claim 1. Description: