JP4277179B2 - Method for producing polydiene - Google Patents

Description

【００２９】
以上のように、本発明の実施例で用いたオクチル酸コバルトは、トルエンに対して任意の割合で溶解する溶解性の高い化合物である。一方、臭化コバルト・トリス（３−メチルフェニルホスフィン）錯体［CoBr₂・2P(m-CH₃C₅H₄)₃］のトルエンに対する溶解度はわずか０．４％であり、大量の溶媒を必要とするため工業的に使用するには大きな調整タンクを必要とする。特公昭４４−３２４２５公報や特開平１−２４９７８８公報で示された錯体を使用する方法と比較して、本発明は高濃度のコバルト触媒を使用することができ効率的な生産が可能になる。
また、本発明は Journal of Polymer Science, Vol40, 3086-3092(2002)に示された塩化コバルトをスラリー状態で使用する方法と比較すると、コバルト量で約１／３、アルミノキサン量で約１／１０と少なく、触媒が効率的に活用されていることが分かる。
【００３０】
【発明の効果】
本発明によれば、触媒系として、コバルト塩、ホスフィン化合物、活性ハロゲンを含有する化合物およびアルミノキサンを用いて調製し、この触媒系を使用して、１，３−ジエン類を、炭化水素溶媒中でかつ水を混入させることなく重合することで、高い結晶化度を有するポリエンを効率よく製造することができる。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a polydiene, and more particularly, a 1,2-polydiene having crystallinity using a specific catalyst system in which the resulting polymer has a high vinyl bond content and a molecular weight controllable. It relates to the manufacturing method.
[0002]
[Prior art]
Conventionally, 1,2-polybutadiene is a catalyst composed of a phosphine complex of a cobalt salt, a trialkylaluminum, and water (Patent Document 1, Patent Document 2), or a catalyst composed of a cobalt salt slurry, a phosphine solution, and methylaluminoxane (non-patent). It is obtained by reference 3).
In the catalyst systems described in these, when a phosphine complex of cobalt salt is used, the solubility of the phosphine complex in an organic solvent is low, so the equipment for preparing the catalyst component becomes large, and excessive investment is required. In addition, when cobalt chloride slurry is used, it is necessary to use a large number of catalysts in order to obtain a polymer with low catalyst efficiency, and coloring of the polymer by residual catalyst becomes a problem.
[0003]
[Patent Document 1]
Japanese Patent Publication No. 44-32425 [Patent Document 2]
JP-A-1-249788 [Non-Patent Document 3]
Dilip CDNath, Takeshi Shiono and Tomiki Ikeda, Journal of Polymer Science, Vol40, 3086-3092 (2002)
[0004]
[Problems to be solved by the invention]
The present invention has been made in the background of the above-mentioned problems of the prior art. By using (A) a cobalt salt, (B) a phosphine compound, (C) a compound containing an active halogen, and (D) an aluminoxane, Production of polydienes with a high degree of crystallinity that can be prepared as a high concentration catalyst component and have a high degree of crystallinity with high vinyl bond content and molecular weight control, using a specific catalyst system in which a polymer can be obtained with a small amount of catalyst Regarding the method.
[0005]
[Means for Solving the Problems]
The present invention uses a catalyst system comprising (A) a cobalt salt, (B) a phosphine compound, (C) an active halogen compound, and (D) an aluminoxane to convert 1,3-dienes into a hydrocarbon solvent. The present invention relates to a process for producing a polydiene, characterized in that polymerization is carried out without mixing water .
[0006]
DETAILED DESCRIPTION OF THE INVENTION
The (A) cobalt salt used in the catalyst system of the present invention includes cobalt acetate, cobalt lactate, cobalt octylate, cobalt octoate, cobalt stearate, cobalt versatate and cobalt naphthenate. Of these, cobalt octylate, cobalt octoate, and cobalt versatate, which are highly soluble in organic solvents, are preferred.
[0007]
Examples of the (B) phosphine compound include diphenylcyclohexylphosphine, diphenylisopropylphosphine, diphenylisobutylphosphine, diphenylt-butylphosphine, diphenylcyclopentylphosphine, diphenyl (4-methylcyclohexyl) phosphine, diphenylcyclopentylphosphine, and diphenylcyclooctyl. Diphenylalkylphosphines such as phosphine, triphenylphosphine, tris (3-methylphenylphosphine), tris (3,5-dimethylphenylphosphine), tris (4-methoxyphenylphosphine), tris (3,5-dimethyl, And 4-phenylphenylphosphine).
[0008]
Furthermore, examples of the active halogen-containing compound (C) include methyl aluminum halides such as dimethylaluminum chloride, methylaluminum dichloride, dimethylaluminum bromide, methylaluminum dibromide, dimethylaluminum fluoride, and methylaluminum difluoride And aluminum halide compounds such as diethylaluminum chloride, ethylaluminum dichloride, diethylaluminum bromide, ethylaluminum dibromide, diethylaluminum fluoride, ethylaluminum difluoride and the like;
Boron fluoride complexes such as boron fluoride phenol complex and boron fluoride ether complex;
Halogenated silane compounds such as methyltrichlorosilane, dimethylchlorosilane, dimethyldichlorosilane, trimethylchlorosilane, tetrachlorosilane;
Metal halide compounds such as titanium tetrachloride and tin tetrachloride;
Organic active halides such as benzyl chloride, allyl chloride, dibromomethane, dichloroethane, dibromoethane;
Etc.
Among these (C) components, from the viewpoint of polymerization activity, an aluminum halide compound, a metal halide compound, a halogenated silane compound, and an organic active halide are preferable.
Furthermore, examples of the aluminoxane as component (D) include methylaluminoxane, ethylaluminoxane, butylaluminoxane, and the like, and among these, methylaluminoxane is most preferable. These alkylaluminoxanes may be synthesized in advance or may be synthesized in a polymerization system with trialkylaluminum and water.
[0009]
In the catalyst used in the present invention, a cobalt catalyst obtained by mixing (C) component and (A) component or (C) component, (A) component and (B) component in advance is used. By contacting the cobalt catalyst with the components (B) and (D) in the former and the component (D) in the latter, the polymer can be produced efficiently.
Alternatively, the polymer can be efficiently produced by previously contacting the aluminum promoter obtained by mixing the component (C) and the component (D) with the component (A) and the component (B).
[0010]
In the catalyst system used in the present invention, the ratio of (A) cobalt salt, (B) phosphine compound and (C) active halogen-containing compound is (B) phosphine to 1 mol of (A) cobalt salt. The compound is preferably 0.5 to 5 mol, and the use ratio of the compound containing (C) active halogen is 0.5 to 10 mol with respect to 1 mol of (A) cobalt salt.
Moreover, the usage-amount of the cobalt salt of (A) component is 5,000-200,000 in the molar ratio (1,3-dienes / Co) of 1,3-dienes and a cobalt atom, Preferably it is 10,000. It is in the range of ˜150,000. If the 1,3-dienes / Co (molar ratio) is less than 5,000, the resulting polymer has poor mechanical strength, whereas if it exceeds 200,000, the polymerization activity is lowered.
Furthermore, the amount of component (D) (aluminoxane) used is 500 to 4,000, preferably in terms of the molar ratio of 1,3-dienes to aluminum atoms in component (D) (1,3-dienes / Al). It is the range of 1000-3,000. If the 1,3-dienes / Al (molar ratio) is less than 500, it is economically disadvantageous, while if it exceeds 4,000, the polymerization activity decreases. In addition, as ratio (Al / Co) of the aluminum atom of (D) component with respect to the cobalt atom of (A) component, it is 5-300 normally, Preferably it is about 7.5-100. When Al / Co (atomic ratio) is less than 5, the polymerization activity is lowered, while when it exceeds 300, it is economically disadvantageous.
[0011]
Examples of the inert organic solvent used for the catalyst preparation include aromatic hydrocarbons such as benzene, toluene, and xylene, aliphatic hydrocarbons such as butane, butene, pentane, pentene, hexane, heptane, and octane, cyclopentane, and cyclohexane. Alicyclic hydrocarbons such as methylene chloride, 1,2-dichloroethane, 1,1,1-trichloroethane, chlorinated hydrocarbons such as chlorobenzene, o-dichlorobenzene, p-dichlorobenzene, and mixtures thereof can do.
In addition, it is also preferable to use the same solvent as a polymerization solvent as an inert organic solvent used for catalyst preparation.
[0012]
In the present invention, 1,3-dienes are polymerized in a hydrocarbon solvent using a catalyst system mainly composed of the components (A), (B), (D) and (C), and 5% 1,2-polydienes having a crystallinity of 40% can be produced.
[0013]
In the present invention, 1,3-dienes include compounds of 1,3-butadiene, 4-alkyl-substituted-1,3-butadiene, and 2-alkyl-substituted-1,3-butadiene. Among these, as 4-alkyl substituted 1,3-butadiene, 1,3-pentadiene, 1,3-hexadiene, 1,3-heptadiene, 1,3-octadiene, 1,3-nonadiene, 1,3- Examples include decadien. Representative examples of 2-alkyl-substituted-1,3-butadiene include 2-methyl-1,3-butadiene (isoprene), 2-ethyl-1,3-butadiene, 2-propyl-1,3-butadiene. Butadiene, 2-isopropyl-1,3-butadiene, 2-butyl-1,3-butadiene, 2-isobutyl-1,3-butadiene, 2-amyl-1,3-butadiene, 2-isoamyl-1,3- Butadiene, 2-hexyl-1,3-butadiene, 2-cyclohexyl-1,3-butadiene, 2-isohexyl-1,3-butadiene, 2-heptyl-1,3-butadiene, 2-isoheptyl-1,3- Examples include butadiene, 2-octyl-1,3-butadiene, and 2-isooctyl-1,3-butadiene. Of these conjugated dienes, 1,3-butadiene and isoprene are preferred, and 1,3-butadiene is most preferred.
[0014]
Examples of the hydrocarbon solvent used as a polymerization solvent include aromatic hydrocarbons such as benzene, toluene, and xylene, aliphatic hydrocarbons such as butane, butene, pentane, pentene, hexane, heptane, and octane, cyclopentane, and cyclohexane. Examples include alicyclic hydrocarbons, chlorinated hydrocarbons such as methylene chloride, 1,2-dichloroethane, 1,1,1-trichloroethane, chlorobenzene, o-dichlorobenzene, p-dichlorobenzene, and mixtures thereof. Preferably, cyclohexane, heptane, toluene, methylene chloride, etc. are mentioned. More preferred are non-halogen hydrocarbon solvents such as cyclohexane, heptane, and toluene from the viewpoint of non-halogen.
[0015]
The polymerization temperature is usually −20 ° C. to + 120 ° C., preferably + 10 ° C. to + 90 ° C. The polymerization reaction may be batch or continuous. In addition, the monomer concentration in a solvent is 5 to 80 weight% normally, Preferably, it is 8 to 40 weight%.
Further, in order to produce a polymer, in order not to deactivate the catalyst and the polymer of the present invention, it is necessary to minimize the mixing of a deactivating compound such as oxygen, water or carbon dioxide gas in the polymerization system. Consideration is necessary.
When the polymerization reaction has proceeded to the desired stage, the reaction mixture is added with a polymerization terminator such as alcohol, an anti-aging agent, an antioxidant, an ultraviolet absorber, etc., and then the polymer produced is separated and washed according to the usual method. The desired polydiene can be obtained by drying.
[0016]
The polydiene obtained by the production method of the present invention has a vinyl bond content of 85% or more, preferably 90% or more.
The degree of crystallinity can be adjusted by the type of phosphine compound used and the polymerization temperature.
The crystallinity of the polydiene obtained by the present invention is preferably 5 to 40%, more preferably 10 to 35%. If it is less than 5%, the mechanical strength is inferior. On the other hand, if it exceeds 40%, the workability is inferior.
In the present invention, when the polydiene obtained is crystalline 1,2-polybutadiene, the crystallinity is preferably 5 to 40%, more preferably 10 to 35%.
The crystallinity of the polydiene can be adjusted by adjusting the polymerization temperature and the type and amount of the phosphine compound (B).
Furthermore, the molecular weight of the polydiene (1,2-polydiene) obtained in the present invention is a weight average molecular weight in terms of polystyrene and is usually 50,000 to 600,000. If it is less than 50,000, the strength properties are inferior, while if it exceeds 600,000, the workability becomes inferior. The molecular weight can be adjusted by the ratio of aluminum atom / cobalt atom.
[0017]
According to the present invention, a polydiene such as crystalline 1,2-polybutadiene obtained by polymerizing dienes such as 1,3-butadiene may be used alone or blended with other synthetic resins, synthetic rubbers, or natural rubbers. Ordinary vulcanized rubber such as carbon black and other fillers, vulcanizing agents, and vulcanization accelerators. By adding a compounding agent and vulcanizing it as a rubber composition, applications that require mechanical properties and abrasion resistance, such as tires, hoses, belts, sponges, footwear materials, sheets, films, tubes, packaging materials, It can be used for resin modifiers, photosensitive materials, and other various industrial products.
[0018]
【Example】
EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated further more concretely, this invention is not restrict | limited at all to the following Examples, unless the summary is exceeded.
In the examples, parts and% are based on weight unless otherwise specified.
In addition, various measurements in the examples were based on the following methods.
[0019]
The vinyl bond content (1,2-bond content) of 1,2-polybutadiene was determined by an infrared absorption spectrum method (Morello method).
The crystallinity of 1,2-polybutadiene is such that the density of 1,2-polybutadiene having a crystallinity of 0% is 0.889 g / cm ³ and the density of 1,2-polybutadiene having a crystallinity of 100% is 0.963 g / cm ² . It was converted from the density measured by the underwater substitution method as cm ³ .
The weight average molecular weight (Mw) was measured in terms of polystyrene using gel permeation chromatography (GPC) at 40 ° C. and tetrahydrofuran as a solvent.
The melt flow index (MI) was the amount of resin (g) that flowed out in a time corresponding to 10 minutes under the conditions of a temperature of 150 ° C. and a load of 2.16 kg by the melt flow indexer.
[0020]
Example 1
Preparation of catalyst solution:
In a dry nitrogen atmosphere, in a 30 ml pressure bottle, 2 ml of toluene, (A) 0.1 mol / L toluene solution of cobalt octylate, 0.25 ml, (B) 0.1 mol / ml of tris (3-methylphenylphosphine) 0.31 ml of L toluene solution and 0.1 mol / L toluene solution of (C) dimethylaluminum chloride were added and stirred at room temperature for 10 minutes. To this, 2.95 ml of toluene solution (D) 1% methylaluminoxane (as Al atoms) was added and stirred for another 10 minutes to obtain a cobalt catalyst solution.
[0021]
Polymerization of 1,3-butadiene:
In a dry nitrogen atmosphere, in a 500 ml pressure bottle, 60 ml of 1,3-butadiene (BD) and 248 ml of cyclohexane were added, 0.70 ml of the obtained cobalt catalyst solution was added, and polymerization was performed in a constant temperature water bath at 36 ° C. for 60 minutes.
The reaction was stopped by adding a small amount of ethanol as a stopper.
Next, 0.3 parts of 2,6-di-t-butyl-p-cresol was added to 100 parts of the polymer, heated on a hot plate, and the solvent was removed to obtain the polymer. The polymerization conversion was determined. Table 1 shows the ratio of each catalyst component and butadiene and the polymerization results.
[0022]
Examples 2-7
In the same manner as in Example 1, a cobalt catalyst solution was prepared using the cobalt salt, phosphine compound and active halide shown in Table 1. Polymerization of 1,3-butadiene was carried out under the conditions shown in Table 1 with the amount of cobalt salt, the amount of phosphine compound and the amount of active halide. The results are shown in Table 1.
[0023]
Comparative Examples 1-2
Using the same method as in Example 1, a solution was prepared in the same manner without adding any of the cobalt salt, phosphine compound and active halide shown in Table 1, and an attempt was made to polymerize butadiene. The results are shown in Table 1.
[0024]
If there is no active halide, the polymerization activity is extremely low and not only the production cost is industrially increased, but also the cobalt residue is increased, which is not preferable. Further, 1,2-polybutadiene could not be obtained without phosphine.
[0025]
As is clear from Table 1, in Examples 1 to 5, a polymer with a high crystallinity can be obtained in a high yield at a polymerization temperature of 36 ° C. Polymerization was obtained only in a low yield without polymerization.
[0026]
Examples 8-10
Table 1 shows the results of experiments with different types of active halogen compounds.
As is apparent from Table 1, crystalline 1,2-polybutadiene was obtained in good yield even with an active halide such as a halogenated silane compound or titanium tetrachloride. The results are shown in Table 1.
[0027]
Example 11
Polymerization was conducted in the same manner as in Example 1 except that butadiene of Example 1 was changed to 54 ml of butadiene and 7 ml of isoprene. In the produced polymer, 7.1% of isoprene was copolymerized. The melting point of the polymer was 87 ° C., and it was a crystalline butadiene / isoprene copolymer. The results are shown in Table 1.
[0028]
[Table 1]

[0029]
As described above, cobalt octylate used in Examples of the present invention is a highly soluble compound that dissolves in an arbitrary ratio with respect to toluene. On the other hand, the solubility of cobalt bromide-tris (3-methylphenylphosphine) complex [CoBr ₂ · 2P (m-CH ₃ C ₅ H ₄ ) ₃ ] in toluene is only 0.4%, requiring a large amount of solvent. Therefore, a large adjustment tank is required for industrial use. Compared with the method using the complex disclosed in Japanese Patent Publication No. 44-32425 and Japanese Patent Application Laid-Open No. 1-249788, the present invention can use a high-concentration cobalt catalyst and enables efficient production.
In addition, the present invention is about 1/3 in terms of cobalt and about 1/10 in terms of aluminoxane, compared with the method of using cobalt chloride shown in Journal of Polymer Science, Vol 40, 3086-3092 (2002) in a slurry state. It can be seen that the catalyst is used efficiently.
[0030]
【The invention's effect】
According to the present invention, a catalyst system is prepared using a cobalt salt, a phosphine compound, an active halogen-containing compound and an aluminoxane , and this catalyst system is used to convert 1,3-dienes in a hydrocarbon solvent. In addition, by polymerizing without mixing water, a polyene having a high crystallinity can be efficiently produced.

Claims (10)

Using a catalyst system comprising (A) a cobalt salt, (B) a phosphine compound, (C) a compound having an active halogen, and (D) an aluminoxane, 1,3-dienes can be converted in a hydrocarbon solvent and water A method for producing a polydiene, characterized in that polymerization is carried out without mixing .   The catalyst of the polydiene according to claim 1, wherein a cobalt catalyst obtained by mixing (C) component and (A) component or (C) component, (A) component and (B) component in advance is used as the catalyst system. Production method.   The method for producing a polydiene according to claim 1, wherein a promoter obtained by previously mixing the component (C) and the component (D) is used as the catalyst system.   (A) The usage ratio of the component (B) to 1 mol of the component is 0.5 to 5 mol, and the usage ratio of the component (C) to 1 mol of the component (A) is 0.5 to 10 mol. The manufacturing method of the polydiene in any one of -3.   The component (A) is at least one selected from the group consisting of cobalt acetate, cobalt lactate, cobalt octylate, cobalt octoate, cobalt stearate, cobalt versatate and cobalt naphthenate. Process for producing polydienes.   The method for producing a polydiene according to any one of claims 1 to 5, wherein the component (C) is at least one selected from the group consisting of an aluminum halide compound, a metal halide compound, a halogenated silane compound, and an organic active halide.   The method for producing a polydiene according to any one of claims 1 to 6, wherein the hydrocarbon solvent is at least one selected from the group consisting of cyclohexane, hexane and methylene chloride.   Polymerization temperature is -20 degreeC-+120 degreeC, The manufacturing method of the polydiene in any one of Claims 1-7.   The method for producing a polydiene according to any one of claims 1 to 8, wherein the polydiene obtained has a crystallinity of 5 to 40%.   The method for producing a polydiene according to any one of claims 1 to 9, wherein the polydiene obtained is crystalline 1,2-polybutadiene having a crystallinity of 5 to 40%.