JPH0873515A - Process for polymerizing conjugated diolefin - Google Patents

Abstract

PURPOSE: To provide a process for polymerizing a conjugated diolefin whereby a (co)polymer having a narrow mol.wt. distribution is obtd. at a high productivity even when a catalyst system contg. a group 3B metal is used by using a specific catalyst system. CONSTITUTION: A conjugated diolefin is polymerized by using a catalyst system comprising a compd. (A) of a group 3B metal, an organoaluminum compd. (B) represented by AlR<1> R<2> R<3> (wherein R<1> and R<2> are each a hydrocarbon group; and R<3> is H or a hydrocarbon group), an aluminoxane (C), and a compd. (D) having at least one halogen atom. A neodymium compd. is the most suitable as the compd. of a group 3B metal, and a carboxylate of the metal is pref., a 2-ethylhexanoate and a versatate being still pref. The component D is a halogenated (alkyl)aluminum compd. represented by AlXn R<6> 3-n (wherein X is halogen; R<6> is a 1-8C hydrocarbon group; and n is 1-2) or an organohalogen compd.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention uses a conjugated diolefin or a mixture of conjugated diolefins to produce high cis-1,4.
The present invention relates to a method for producing a polymer or copolymer having a structure. More specifically, the present invention relates to improvements in catalysts for producing polymers or copolymers having a high cis-1,4 structure.

[0002]

As a method for obtaining a conjugated diolefin polymer such as polybutadiene having a high cis-1,4 structure, a catalyst in which a transition metal compound and an organic metal are combined is known.
For example, a catalyst composed of a combination of a titanium compound and an organoaluminum, a combination of a cobalt compound and an organoaluminum compound, a nickel compound, a boron trifluoride and an organoaluminum compound is often used.

On the other hand, as a polymerization catalyst using a metal compound of Group 3B of the periodic table, Japanese Patent Publication No. 47-14729 discloses a compound of a metal of Group 3B of the periodic table such as cerium octanoate and diisobutylaluminum. Alkali aluminum hydrides such as hydride and trialkylaluminum and aluminum halides such as ethylaluminium dichloride have been shown to be a catalyst system, and it has been shown that aging the catalyst particularly in the presence of butadiene increases the catalytic activity. There is.

Further, Japanese Patent Publication Nos. 62-1404 and 6-6
No. 3-64444 and Japanese Patent Publication No. 1-16244 propose a method of enhancing the catalytic activity by increasing the solubility of a compound of a rare earth element in a polymerization solvent. Further, JP-B-4-2601 discloses a catalyst system composed of a compound of a metal of Group 3B of the periodic table, a trialkylaluminum or aluminum halide and an organic halogen derivative 1,3.
-It has been shown to be more active than before in the polymerization of butadiene. Further, Polymer Communication (Polymer Communication 32 No17 p514 1991) shows that the polymerization activity is increased by using a two-component system of a compound of neodymium or a transition metal compound such as titanium and methylaluminoxane.

[0005]

However, these conventional catalyst systems containing a metal compound of Group 3B of the Periodic Table are not yet sufficiently active per catalyst, for example, a catalyst system containing a cobalt compound as a main component. It was much less active. Further, a polymer obtained by a conventional catalyst system containing a metal compound of Group 3B of the Periodic Table has a drawback that the molecular weight distribution is widened and abrasion resistance and impact resilience are lowered. Further, the method of polymerizing two components of a neodymium compound or a transition metal compound and an aluminoxane requires the use of a large amount of expensive aluminoxane, which is not industrially feasible. The present invention has been made to solve the above problems, and by providing a novel catalyst system, even if the catalyst system contains a metal compound of Group 3B of the Periodic Table, it is expensive. Productivity is so good that it can be industrially established without using a large amount of xanthane,
It is also an object of the present invention to provide a method for polymerizing a conjugated diolefin which gives a polymer having a narrow molecular weight distribution.

[0006]

The present invention includes (a) a metal compound of Group 3B of the periodic table, (b) an organoaluminum compound represented by AlR ¹ R ² R ³ , (wherein R ¹ and R
² is the same or different hydrocarbon group, R ³ is hydrogen or a hydrocarbon group, and R ³ may be the same as R ¹ or R ² . ) (C) Aluminoxane, (d) a compound having at least one halogen atom, and a method for polymerizing a conjugated diolefin, the method comprising polymerizing a conjugated diolefin using a catalyst. is there.

First, the catalyst component of the present invention will be described. The metal constituting the metal compound of Group 3B of the periodic table, which is the component (a) of the present invention, is a metal selected from the elements of atomic numbers 21 to 103 belonging to Group 3B of the periodic table. Preferred is neodymium, praseodymium, cerium, lanthanum, gadolinium or a mixture thereof, and more preferred is neodymium.

The metal compound of Group 3B of the Periodic Table of the present invention is a carboxylate, alkoxide, β-diketone complex, phosphate or phosphite of a metal of Group 3B of the Periodic Table. , Carboxylic acid salts or phosphoric acid salts are preferred, and carboxylic acid salts are particularly preferred.

The carboxylate of a metal of Group 3B of the Periodic Table is represented by the general formula (R ⁴ CO ₂ ) ₃ M (M is a metal of Group 3B of the Periodic Table), and R ⁴ is carbon. It represents a hydrocarbon substituent of formula 1 to 20, is preferably a saturated or unsaturated alkyl group, and is linear, branched or cyclic, and the carboxyl group is a primary, secondary or tertiary carbon atom. Are bound to. Specifically, octanoic acid, 2-ethyl-hexanoic acid, oleic acid, stearic acid, benzoic acid,
Examples thereof include salts such as naphthenic acid and versatic acid (trade names of Shell Chemistry, which is a carboxylic acid having a carboxyl group bonded to a tertiary carbon atom), 2-ethyl-
Hexanoic acid and versatic acid salts are preferred.

The alkoxide of the metal of Group 3B of the periodic table is one represented by the general formula (R ⁴ O) ₃ M (wherein M and R ⁴ are the same as above), and R ⁴ O Examples of the alkoxy group represented by 2-ethyl-hexylalkoxy, oleylalkoxy, stearylalkoxy,
Examples include phenoxy and benzylalkoxy groups.
Among these, 2-ethyl-hexylalkoxy and benzylalkoxy groups are preferable.

Examples of the β-diketone complex of the metal of Group 3B of the periodic table include acetylacetone, benzoylacetone, propionitrileacetone, of the metal of Group 3B of the periodic table,
Examples thereof include valerylacetone and ethylacetylacetone complex. Among these, acetylacetone and ethylacetylacetone complexes are preferable.

The phosphate or phosphite of a metal of Group 3B of the Periodic Table includes bis (2-ethylhexyl) phosphate and bis (1-methylheptyl) phosphate of a metal of Group 3B of the Periodic Table. , Bis (p-nonylphenyl) phosphate, bis (polyethylene glycol-p-nonylphenyl) phosphate, (1-methylheptyl) phosphoric acid (2-ethylhexyl), phosphoric acid (2-ethylhexyl) (p-nonylphenyl) ), 2-ethylhexylphosphonic acid mono-2-ethylhexyl, 2-ethylhexylphosphonic acid mono-p
-Nonylphenyl, bis (2-ethylhexyl) phosphinic acid, bis (1-methylheptyl) phosphinic acid, bis (p-nonylphenyl) phosphinic acid, (1-methylheptyl) (2-ethylhexyl) phosphinic acid, (2
-Ethylhexyl) (p-nonylphenyl) phosphinic acid and the like are mentioned, and preferable examples include bis (2-ethylhexyl) phosphate, bis (1-methylheptyl) phosphate, and 2-ethylhexylphosphonic acid mono-2. -Ethylhexyl and bis (2-ethylhexyl) phosphinic acid salts are mentioned.

Of the above examples, particularly preferred are neodymium phosphates or neodymium carboxylates, and especially neodymium 2-ethyl-hexanoate and neodymium versatic acid salts. .

Next, AlR ¹ which is the component (b) of the present invention
Examples of the organic aluminum compound represented by R ² R ³ include
Trimethyl aluminum, triethyl aluminum, triisopropyl aluminum, triisobutyl aluminum, trihexyl aluminum, tricyclohexyl aluminum, diethyl aluminum hydride, diisobutyl aluminum hydride, and the like, triethyl aluminum, triisobutyl aluminum,
Diethyl aluminum hydride and diisobutyl aluminum hydride are preferred. These may be a mixture of two or more.

Next, the aluminoxane which is the component (c) of the present invention is a compound having a structure represented by the formula (I) or the formula (II).

[0016]

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[0017]

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(In the formula, R ₅ is a hydrocarbon group, and m is an integer of 2 or more.)

In the aluminoxane represented by the formula (I) or the formula (II), examples of the hydrocarbon group represented by R ₅ include methyl, ethyl, propyl and butyl groups, preferably methyl. Alternatively, it is an ethyl group, and particularly preferably a methyl group. Further, m is an integer of 2 or more, preferably 5 or more, more preferably 10 to 100. Specific examples of the aluminoxane include methylaluminoxane, ethylaluminoxane, propylaluminoxane, butylaluminoxane, and the like.

Next, the compound having at least one halogen atom, which is the component (d) of the present invention, has the general formula Al
X _n R ⁶ _3-n (X is chlorine, bromine, fluorine and iodine, R ⁶
Represents a hydrocarbon substituent having 1 to 8 carbon atoms, and n represents a natural number in the range of 1 to 2. ) Is a halogenated (alkyl) aluminum compound or an organic halogen compound.

[0021] As the AlX _n R ⁶ _3-n halide represented by (alkyl) aluminum compound, dimethyl aluminum chloride, diethyl aluminum chloride, diethyl aluminum bromide, diethyl aluminum iodide, diethyl aluminum fluoride, di - n-propyl aluminum chloride, di-
n-Butyl aluminum chloride, di-isobutyl aluminum chloride, methyl aluminum-di-chloride, ethyl aluminum-di-chloride, isobutyl aluminum-di-chloride, sesquimethyl aluminum chloride, sesquiethyl aluminum chloride, sesqui-isobutyl aluminum chloride, aluminum Examples include trichloride, aluminum tribromide, aluminum triiodide, aluminum trifluoride and mixtures thereof.

Examples of the above organic halogen compounds include benzoyl chloride, propionyl chloride, benzyl chloride, benzylidene chloride, tert-butyl chloride and the like; benzoyl bromide, propionyl bromide, benzyl bromide, benzylidene bromide, tert-butyl bromide and the like. Organic bromine compound; methyl chloroformate or methyl bromoformate; chlorodiphenylmethane, chlorotriphenylmethane and the like.

The amount of the catalyst used in the present invention is such that the component (a) is 0.
It is preferable to use an amount of 0001 to 1.0 mmol. 0.
This is because if it is less than 0001 mmol, it is not preferable from the viewpoint of polymerization activity, and if it exceeds 1.0 mmol, the catalyst concentration becomes high and a deashing step is required. Especially 0.0005 to 0.
More preferably, an amount of 1 mmol is used. The ratio of the catalyst component is molar [Al gram atom in the component (c)] ratio, and the ratio of the component (a) to the component (b) is 1: 1 to 1: 5.
000, preferably 1: 5 to 1: 1000, more preferably 1:10 to 1: 700, and the ratio of component (a) to component (c) is 1:10 to 1: 5000, preferably 1: 3 to 1:10.
00, more preferably 1: 5 to 1: 700, component (a) to component (d) 1: 0.1 to 1:15, preferably 1 :.
0.5 to 1: 8, more preferably 1: 1 to 1: 5,
The component (b) to the component (c) is 1: 0.01 to 1: 100,
It is preferably 1: 0.03 to 1:50, more preferably 1: 0.05 to 1:10. If the amount of the catalyst or the ratio of the components constituting the catalyst is out of the range, the catalyst does not act as a highly active catalyst and a conjugated diolefin polymer having a narrow molecular weight distribution cannot be obtained.

These catalysts are (a), (b), (c)
And (d) each component is separately mixed, or each catalyst component is sequentially added to a conjugated diolefin (may be a mixed solution of a conjugated diolefin and a polymerization solvent) (hereinafter referred to as a polymerization system) in a polymerization vessel. It is adjusted by adding. The catalyst in which the respective components are mixed is preferably aged in the presence or absence of the conjugated diolefin prior to the polymerization in order to narrow the catalytic activity and the molecular weight distribution. In particular, it is more preferable to perform aging in the presence of a conjugated diolefin.

The order of preparing the components of the catalyst is to first mix (a) the Group 3B metal compound of the periodic table with (b) the organoaluminum compound or (c) the aluminoxane. Are particularly preferable for narrowing the catalytic activity and the molecular weight distribution. So, for example,
(A), (b), (c), (d) in this order, (b),
(A), (c), (d) in order, (b), (a),
It is possible to sequentially add and mix them in the order of (d) and (c). Further, a part of the component (b) may be added to the polymerization system and the rest may be used for aging.

When the catalyst is aged in the presence of the conjugated diolefin, the amount of the conjugated diolefin used is usually 0.1 or more, preferably 1 or more in molar ratio with respect to the component (a). Good. In this case, when aging the catalyst separately outside the polymerization system, the amount of the conjugated diolefin used is (a)
It is preferable from the viewpoint of handling that the molar ratio to the components is usually 1000 or less, particularly 500 or less. This is because if the molar ratio of the conjugated diolefin to the component (a) exceeds 1,000, the polymerization substantially proceeds, the viscosity of the catalyst increases, and it becomes difficult to add it to the polymerization system. During the aging,
It is not always necessary to mix all of the catalyst components before aging. For example, after aging only a few components including the component (a), the conjugated diolefin is added to the polymerization system, and then the remaining 2 to 3 components are added. 1 catalyst component may be added, and further,
It may be a method in which 2-3 components including the component (a) are sequentially added to the polymerization system for aging, and then the remaining 2-1 components are added to initiate the polymerization.

The aging temperature is 0 to 100 ° C, preferably 20 to 80 ° C. If the temperature is lower than 0 ° C, the aging is not sufficiently performed, and if the temperature exceeds 100 ° C, the catalytic activity is lowered and the molecular weight distribution is broadened, which is not preferable. The aging time is not particularly limited, but usually 0.5 minutes or more is sufficient,
It is stable for several days.

The conjugated diolefin used in the present invention is a diolefin having a pair of conjugated double bonds, and examples thereof include 1,3-butadiene and 2-methyl-1,3.
-Butadiene (isoprene), 2,3-dimethyl-1,
Examples include 3-butadiene, 1,3-pentadiene, and 1,3-hexadiene. Of these, 1,3-butadiene, isoprene and 1,3 are particularly preferably used.
-Pentadiene. Further, two or more kinds of these conjugated diolefins may be mixed and used, and in this case, a copolymer is obtained.

Polymerization of the conjugated diolefin can be carried out with a solvent or without a solvent. When a solvent is used, examples of the solvent include saturated aliphatic hydrocarbons such as butane, pentane, hexane and heptane; saturated alicyclic hydrocarbons such as cyclopentane and cyclohexane; 1-butene, 2-
Mono-olefins such as butene; aromatic hydrocarbons such as benzene and toluene; methylene chloride, chloroform, carbon tetrachloride, trichloroethylene, perchlorethylene, 1,
Examples thereof include halogenated hydrocarbons such as 2-dichloroethane, chlorobenzene, bromobenzene, and chlorotoluene.

The polymerization temperature is -30 to 150 ° C, preferably 0 to 100 ° C. The polymerization reaction may be a batch method or a continuous method.

The desired polymer is terminated by adding a known polymerization terminator to the polymerization system after the polymerization reaction reaches a predetermined polymerization rate, and then the produced polymer is separated, washed and dried by a usual method. You can get it.

The polymer of the conjugated diolefin obtained by the present invention is prepared by blending the polymer alone or in a blend with other synthetic rubber or natural rubber, and if necessary, oil-extended with a process oil, and then carbon black. Rubber that is required to have mechanical properties and abrasion resistance for tires, hoses, belts and other various industrial products after vulcanization by adding fillers such as vulcanizing agents, vulcanizing agents, vulcanization accelerators and other common compounding agents Used for purposes.
It can also be used by blending with other rubbers.

[0033]

EXAMPLES The present invention will be specifically described below based on examples, but the invention is not limited thereto. The microstructure of the obtained polybutadiene in the examples was determined from the 0.4 g / dl carbon disulfide solution by the Morello method using an infrared spectrophotometer. GPC 801 manufactured by Tosoh Corporation
0 system (column: KF-800D + KF-805L
* 2) for polystyrene equivalent number average molecular weight (M
n) and the weight average molecular weight (Mw) were calculated, and the molecular weight spread and molecular weight distribution (Mw / Mn) were calculated. The measurement conditions are a temperature of 40 ° C. and a tetrahydrofuran solution of 2 g / l. The solvent and conjugated diolefin monomer are molecular sieves 3
It was dehydrated with A and used. When preparing the catalyst solution, the amount of each catalyst component used was adjusted to 15 times the amount used in the polymerization, and 1/15 of the catalyst solution was used in the polymerization.

Example 1 After replacing a flask having a capacity of 50 ml with nitrogen, 9.5 ml of a cyclohexane solution containing 14.25 mmol of diisobutylaluminum hydride at room temperature and a cyclohexane solution containing 1.5 mmol of 1,3-butadiene 1. 31 ml and neodymium
1.5 ml of a cyclohexane solution containing 0.15 mmol of versatate (neodymium salt of versatic acid of Shell Chemical Co., Ltd.) was added in this order, and the mixture was aged at room temperature for 10 minutes with stirring. Then methyl aluminoxane 0.
0.38 ml of a toluene solution containing 75 mmol was added and aged for 10 minutes, and then a cyclohexane solution containing 0.45 mmol of diethylaluminum chloride was added.
45 ml was added and aged for 30 minutes to prepare a catalyst solution.

After the glass autoclave having a capacity of 1.5 l was replaced with nitrogen, 700 ml of cyclohexane and 140 ml (87 g) of liquefied butadiene were introduced, and 1/15 (0.88 ml) of the above catalyst solution was added, and the mixture was heated at 50 ° C. Polymerized for 1 hour. After polymerization, 2,6-bis (t-butyl) -4-
The reaction was stopped by adding 10 ml of a methanol solution containing 5% of methylphenol (BHT), and then the polymer was precipitated with 1 l of methanol, separated by filtration and separated, and then at 40 ° C.
It was dried in vacuum. Table 1 shows the amount of each catalyst component used during the polymerization and the analysis results of the obtained polymer.

[Examples 2 to 4] The same operation as in Example 1 was repeated except that the amounts of diisobutylaluminum hydride and methylaluminoxane used during the polymerization were changed as shown in Table 1 to obtain a catalyst solution. Was prepared and polymerized. Table 1 also shows the analysis results of the obtained polymer.

Comparative Example 1 In Example 1, the amount of diisobutylaluminum hydride used during polymerization was 1.
A catalyst solution was prepared and polymerized in the same manner as in Example 1 except that 0 mmol was used and methylaluminoxane was not used. Table 1 shows the analysis results of the obtained polymer. It can be seen that, in Comparative Example 1, when the methylaluminoxane was not used, only a polymer having a low catalytic activity and a wide molecular weight distribution was obtained.

Comparative Example 2 In the same manner as in Example 1 except that diisobutylaluminum hydride was not used, and the amount of methylaluminoxane used during the polymerization was 1.0 mmol. A catalyst solution was prepared and polymerized. Table 1 shows the analysis results of the obtained polymer. In Comparative Example 2, it can be seen that the catalytic activity is extremely low by not using diisobutylaluminum hydride.

Example 5 The same operation as in Example 1 was repeated except that the amount of each catalyst component used during polymerization was changed as shown in Table 1 to prepare a catalyst solution and carry out polymerization. It was Table 1 also shows the analysis results of the obtained polymer.

[Example 6] The same as Example 3 except that the order of addition of the catalyst components when preparing the catalyst was methylaluminoxane, 1,3-butadiene, neodymium versatate, diisobutylaluminum hydride, and diethylaluminum chloride. A catalyst solution was prepared and polymerized. Table 2 shows the analysis results of the obtained polymer.

Comparative Example 3 In Example 6, the amount of diisobutylaluminum hydride used during polymerization was 1.
A catalyst solution was prepared and polymerized in the same manner as in Example 6 except that 0 mmol was used and methylaluminoxane was not used. Table 2 shows the analysis results of the obtained polymer.

Comparative Example 4 The procedure of Example 5 was repeated, except that diisobutylaluminum hydride was not used and the amount of methylaluminoxane used during polymerization was 1.0 mmol. A catalyst solution was prepared and polymerized. Table 2 shows the analysis results of the obtained polymer.

[Example 7] The same procedure as in Example 3 was repeated except that the order of addition of the catalyst components when preparing the catalyst was diisobutylaluminum hydride, 1,3-butadiene, neodymium versatate, diethylaluminum chloride, and methylaluminoxane. A catalyst solution was prepared and polymerized. Table 3 shows the analysis results of the obtained polymer.

[Comparative Example 5] In the same manner as in Example 7 except that diisobutylaluminum hydride was not used and the amount of methylaluminoxane used during the polymerization was 1.0 mmol. A catalyst solution was prepared and polymerized. Table 3 shows the analysis results of the obtained polymer.

[Example 8] A catalyst solution was prepared and polymerized in the same manner as in Example 3 except that diethylaluminum chloride was changed to tertiary butyl chloride. Table 4 shows the analysis results of the obtained polymer.

Example 9 A catalyst solution was prepared and polymerized in the same manner as in Example 3 except that neodymium octoate was used instead of neodymium versatate. Table 5 shows the analysis results of the obtained polymer.

[Example 10] A catalyst solution was prepared and polymerized in the same manner as in Example 9 except that the polymerization solvent was changed from cyclohexane to benzene. Table 6 shows the analysis results of the obtained polymer.

Comparative Example 6 A catalyst solution was prepared in the same manner as in Example 10 except that the amount of diisobutylaluminum hydride used during polymerization was 1.0 mmol and methylaluminoxane was not used. Was prepared and polymerized. Table 6 shows the analysis results of the obtained polymer.

Comparative Example 7 In the same manner as in Example 10, except that diisobutylaluminum hydride was not used and the amount of methylaluminoxane used during polymerization was 1.0 mmol. A catalyst solution was prepared and polymerized. Table 6 shows the analysis results of the obtained polymer.

Example 11 A catalyst solution was prepared and polymerized in the same manner as in Example 9 except that 1,3-butadiene at the time of preparing the catalyst and 1,3-butadiene at the time of polymerization were changed to isoprene. Table 7 shows the analysis results of the obtained polymer.

[Example 12] In Example 9, 140 ml of 1,3-butadiene was used as a monomer at the time of polymerization.
A catalyst solution was prepared and polymerized in the same manner as in Example 9 except that the mixture of 70 ml of 3-butadiene and 70 ml of isoprene was used. Table 8 shows the analysis results of the obtained polymer.
The copolymer composition was determined by H-NMR analysis.

[0052]

[Table 1]

[0053]

[Table 2]

[0054]

[Table 3]

[0055]

[Table 4]

[0056]

[Table 5]

[0057]

[Table 6]

[0058]

[Table 7]

[0059]

[Table 8]

[Explanation of symbols in the table] Ali-Bu ₂ H: diisobutylaluminum hydride, BD: 1,3 butadiene, NdV ₃ : neodymium versatate, Nd (Oct) ₃ : neodymium octoate, MAO: methylalumino Xanthan, A
lEt ₂ Cl: Diethyl aluminum chloride, t-BuCl:
t-Butyl chloride C: Ratio of cis-1,4 structure (%), T: trans-
Ratio of 1,4 structure (%), V: Ratio of vinyl-1,2 structure (%), Mn: Number average molecular weight, Mw: Weight average molecular weight

[0061]

INDUSTRIAL APPLICABILITY According to the method for polymerizing a conjugated diolefin of the present invention, by using the novel catalyst system of the present invention, the catalytic activity is high even when a Group 3B metal compound of the periodic table is used. And a polymer having a narrow molecular weight distribution can be obtained.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Main tax Otani 8-1 Goi Minamikaigan, Ichihara-shi, Chiba Ube Industries Ltd. Chiba Research Institute

Claims (1)

[Claims] 1. A metal compound of Group 3B of the periodic table, (b) an organoaluminum compound represented by AlR ¹ R ² R ³ , wherein R ¹ and R ² are the same or different hydrocarbons. R ³ is hydrogen or a hydrocarbon group, provided that R ³ may be the same as or different from R ¹ or R ² ) (c) aluminoxane, (d) at least one A compound having a halogen atom of
A method for polymerizing a conjugated diolefin, which comprises polymerizing a conjugated diolefin using a catalyst composed of