JPH10292009A - Catalyst and production of conjugated diene polymer in the presence of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a conjugated diene polymer having a high cis isomer content, a relatively narrow molecular weight distribution and a low gel fraction in high catalytic activity by using a catalyst obtained from a nickel compound, an ionic compound of a non-coordinating anion with a cation and an organometallic compound containing an element of any one of groups I to III in the periodic table. SOLUTION: The nickel compound (A) used is exemplified by an organic acid salt such as nickel naphthenate, nickel formate or nickel octanoate, an organic complex compound such as nickel acetylacetonate or a nickel alkylbenzenesulfonate. The non-coordinating anion in the ionic compound (B) used is exemplified by a bulky one such as tetraphenylborate, and the cation is exemplified by a carbonium cation or an oxonium action. The organometallic compound (C) used is exemplified by an organoaluminum compound, an organolithium compound or an organomagnesium compound. The mixing ratio by mole is such that A:B is 1:0:1 to 1:10, and A:C is 1:0.1 to 1:1,000.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a novel nickel-based catalyst and a method for producing a conjugated diene polymer using the catalyst.

[0002]

2. Description of the Related Art Numerous proposals have been made for polymerization catalysts for conjugated dienes such as butadiene and isoprene. In particular, since high cis-1,4-polybutadiene has excellent thermal and mechanical properties, catalyst systems such as cobalt, nickel, and neodymium have been developed. However, there are cases where the molecular weight distribution of the formed polymer is widened and gels are easily formed, and depending on the catalyst system, the polymerization activity may be low.

As a nickel-based polymerization catalyst, Internationala
l Rubber Conference 95 Kobe, Preprint 176 (1995) and Polymer Preprints, Japan 43, No. 6, 1708 (1994) report the polymerization of 1,3-butadiene by Ni (acac) ₂ + MAO catalyst system. However, the molecular weight, catalytic activity, and cis content are all low. Japanese Patent Publication No. 43-20470 discloses Ni + BF
_A high cis polybutadiene catalyst consisting of 3.OEt ₂ + AlEt ₃ is disclosed.

[0004]

SUMMARY OF THE INVENTION A novel nickel-based catalyst and a process for producing a highly active conjugated diene polymer using the catalyst having a high cis content, a relatively narrow molecular weight distribution and a low gel content. The purpose is to provide.

[0005]

SUMMARY OF THE INVENTION The present invention provides (A) a nickel compound, (B) an ionic compound of a non-coordinating anion and a cation, and (C) an organometallic element of a Group I to III element of the periodic table. It relates to a catalyst obtained from the compound.

Further, the present invention provides the above-mentioned component (A),
The present invention relates to a catalyst comprising the component (B) and the component (C).

[0007] The present invention also relates to a method for producing a conjugated diene polymer, which comprises polymerizing a conjugated diene compound using the above catalyst.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The nickel compound as component (A) of the catalyst of the present invention includes nickel naphthenate, nickel formate, nickel octanoate, nickel stearate, nickel citrate, nickel benzoate, nickel toluate and the like. Organic acid salts, organic complex compounds such as nickel acetylacetonate, nickel alkylbenzene sulfonate,
Nickel oxyborate and the like can be mentioned.

Among the component (B) of the present invention, the non-coordinating anion constituting the ionic compound of a non-coordinating anion and a cation is preferably a bulky one. 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, tetrafluoroborate, hexafluorophosphate and the like can be mentioned.

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. Also, (alkyl) ₂ N (C ₆ H ₅ ) H
N, N-dialkylanilinium cation having an active proton such as ⁺ , trialkylammonium cation,
Triallyl phosphonium cation, trisubstituted carbonium cation such as (C ₆ H ₅ ) ₃ C ⁺ , oxonium cation,
Examples thereof include a sulfonium cation, a carborane cation, a metal carborane cation, a ferrocenium cation having a transition metal, a cation of a main element metal, a transition metal, and a cation to which ether, amine or the like is coordinated.

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 trityltetra (pentafluorophenyl) borate, triphenylcarboniumtetra (fluorophenyl) borate, N, N-dimethylaniliniumtetra (pentafluorophenyl) borate, 1,1 ′ -Dimethylferrocenium tetra (pentafluorophenyl) borate is preferred. The ionic compounds may be used alone or in combination of two or more.

[0016] Component (C) of the present invention, Periodic Table I-III
As the organometallic compounds of group elements, organoaluminum compounds, organolithium compounds, organomagnesium compounds,
Organic zinc compounds, organic boron compounds and the like can be mentioned.

Specific compounds include methyllithium, butyllithium, phenyllithium, benzyllithium, neopentyllithium, trimethylsilylmethyllithium, bistrimethylsilylmethyllithium, dibutylmagnesium, dihexylmagnesium, diethylzinc, dimethylzinc, trimethylaluminum, Examples thereof include triethylaluminum, triisobutylaluminum, trihexylaluminum, trioctylaluminum, tridecylaluminum, boron trifluoride, and triphenylboron.

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.

The mixing ratio of each catalyst component varies depending on various conditions, but the molar ratio of the nickel compound (A) to the ionic compound (B) is preferably from 1: 0.1.
The ratio is 1:10, more preferably 1: 0.2 to 1: 5.

The molar ratio of the nickel 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: 500.

In the present invention, each catalyst component or 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 a 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.

The order of addition of the catalyst component is not particularly limited, but for example, it can be performed in the following order. The component (A) is added to a contact mixture in which the conjugated diene compound monomer to be polymerized, the component (B) and the component (C) are added in an arbitrary order. 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). To the conjugated diene compound monomer to be polymerized, a mixture in which the component (A), the component (B) and the component (C) are brought into contact in an arbitrary order is added.

The conjugated diene compound monomer which can be polymerized by using the catalyst in the present invention includes 1,3-butadiene, isoprene, 1,3-pentadiene, 2-ethyl-1,3-butadiene, 2,3-dimethylbutadiene, 2-methylpentadiene,
4-methylpentadiene, 2,4-hexadiene and the like. These monomer components may be used alone or in a combination of two or more.

The conjugated diene compound monomer to be polymerized here 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. Besides conjugated dienes, ethylene, propylene, butene-1, butene-2, isobutene, pentene-1, 4-methylpentene-
1, non-cyclic monoolefins such as hexene-1, octene-1, cyclic monoolefins such as cyclopentene, cyclohexene and norbornene, and / or aromatic vinyl compounds such as styrene and α-methylstyrene, dicyclopentadiene, 5-ethylidene It may contain a small amount of non-conjugated diolefin such as 2-norbornene and 1,5-hexadiene.

[0027] 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-
Olefinic hydrocarbons such as butene, mineral spirits, solvent naphtha, hydrocarbon solvents such as kerosene,
Halogenated hydrocarbon solvents such as methylene chloride are exemplified. Further, 1,3-butadiene itself may be used as the polymerization solvent.

Among them, toluene, cyclohexane, a mixture of cis-2-butene and trans-2-butene and the like are preferably used. Bulk polymerization and polymerization using a hydrocarbon solvent having a low boiling point have an advantage that large energy is not required for solvent recovery.

The polymerization temperature is preferably in the range of -100 to 150 ° C, more preferably in the range of -100 to 100 ° C, and more preferably in the range of -50 to 100 ° C.
Is even more preferred.

The polymerization time is preferably in the range of 10 minutes to 12 hours, particularly preferably 30 minutes to 6 hours.

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.

When a conjugated diene is polymerized using the catalyst of the present invention, the microstructure of the obtained polymer is controlled. The content of the cis structure is usually at least 80% by weight, preferably at least 90% by weight, particularly preferably at least 93% by weight.

[0033]

EXAMPLES In the examples, "catalytic activity" means the polymerization time per 1 mmol of the nickel compound used in the polymerization reaction.
Polymer yield per hour (g). The molecular weight distribution is
The evaluation was made by the ratio Mw / Mn of the weight average molecular weight Mw and the number average molecular weight Mn obtained from GPC using polystyrene as a standard substance. Microstructure was performed by infrared absorption spectroscopy. Cis 740 cm ^-1 , transformer 967 cm ^-1 , vinyl 91
The microstructure was calculated from the absorption intensity ratio of 0 cm ^-1 . [Η]
Was measured at a temperature of 30 ° C. in a toluene solution. 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.

Example 1 [Polybutadiene polymerization] (Example 1) The inside of a 1-liter autoclave was replaced with nitrogen, and 300 mL (186 g) of 1,3-butadiene (Bd) was charged.
Then, triethyl aluminum (TE) is used as the component (C).
A) 0.25 mmol, triphenylcarbonium tetrakis (pentafluorophenyl) borate (P
0.03 mmol of h ₃ CB (C ₆ F ₅ ) ₄ ) and 0.01 mmol of nickel octenoate (Ni (Oct) ₂ ) as the component (A) were added thereto.
Polymerization was performed for 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, which was washed, filtered and dried. Tables 2 and 3 show the polymerization results.

(Examples 2 to 4) 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 polymerization results.

[0036]

[Table 1]

[0037]

[Table 2]

[0038]

[Table 3]

[0039]

Industrial Applicability The present invention provides a novel nickel-based catalyst and a method for producing a highly active conjugated diene polymer having a high cis content, a relatively narrow molecular weight distribution and a low gel content using the catalyst. In addition, high cis polybutadiene having a relatively low molecular weight can be produced with high activity.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Yoshiho Baba 8-1, Goi south coast, Ichihara city, Chiba prefecture Ube Industries, Ltd. Polymer Research Laboratory

Claims (3)

[Claims] 1. A catalyst obtained from (A) a nickel 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 the components (A), (B) and (C) according to claim 1. 3. A method for producing a conjugated diene polymer, comprising polymerizing a conjugated diene compound using the catalyst according to claim 1. Description: