JPS58136603A - High-concentration, high-purity dilithium catalyst excellent in storage stability and its production - Google Patents

Abstract

PURPOSE:To obtain a high-concentration, high-purity dilithium catalyst excellent in storage stability and useful in the polymerization of a conjugated diene or the like, by reacting a specified aromatic alkenyl hydrocarbon with a concentrated solution of an organolithium compound in a hydrocarbon solvent. CONSTITUTION:1mol of an aromatic alkenyl hydrocarbon of formulaIor II (wherein R'2 and R'4 are each methyl or ethyl and R'5 is H or methyl) is mixed with 2mol of an organolithium compound of formula III (wherein R6 is a 2-4C alkyl) and a hydrocarbon solvent so that the concentration of the organolithium compound in terms of a lithium atom/hydrocarbon solvent ratio can be at least 0.3mol/liter, and the mixture is reacted. In this way, the titled dilithium catalyst containing at least 90mol%, per lithium, dilithium compound of formula IV or V (wherein R1 and R3 are each a 3-5C alkyl, R2 and R4 are each methyl or ethyl and R5 is H or methyl) is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a high concentration, high purity dilithium catalyst with excellent storage stability and a method for producing the same. Jirichi 9 of the present invention
BACKGROUND ART Polymer catalysts are extremely useful in the homopolymerization or copolymerization of conjugated dienes and aromatic alkenyl hydrocarbons.

As an anionic polymerization catalyst, a dilithium catalyst having two active lithium atoms per initiator molecule is more effective than general monolithium catalysts for the synthesis of double-end functional polymers or block polymers, such as styrene as the A segment, B ABA with segment as butadiene! The synthesis of block polymers is easy, and various dilithium catalysts and the polymerization of dienes using them have been proposed.

This kind of dilithium catalyst has 5 major differences in its manufacturing method.
classified into types. That is, there are five types: those resulting from the reaction between metallic lithium and a dihalogen compound, those resulting from the reaction between metallic lithium and olefins or dienes, and those resulting from the reaction between organolithium and an aromatic hydrocarbon containing a disubstituted vinyl group or alkenyl group. being classified. The present invention belongs to the third type known as the most excellent dilithium catalyst among these.

An example of the first type is the metal lithium (
A dilithioalkane (e.g., 1,4-dilithiobutane) obtained by reacting a dihalogenated alkane with a dihalogenated alkane (U.S. Pat. No. 2,947,795) is known; , dilithium catalyst by reaction with 4-hexadiene.
Rubber Chemistry and Technology (Rub
ber Chemistry and Technology
gy) Volume 49, Page 303, published in 1974, but all of them are insufficient in solubility in hydrocarbon solvents, reproducibility in production, content of bifunctional components, storage stability, etc. However, until now, there have been no examples of industrial use of this material.

The fifth type of dilithium catalyst to which the present invention belongs, ie, the dilithium catalyst produced by the reaction of organic lyticum and an aromatic hydrocarbon containing a disubstituted vinyl group or an alkenyl group, has conventionally been produced by the reaction of dew-butyllithicum and divinylbenzene. Dilithium catalyst obtained - US Pat. No. 51s
No. 48265 was known. According to this patent, it contains 98 moles of dilithium compound per lithium, but in a relatively recent report, -
Paper Presented at the 7
th Akron Chemists-Chemica
l Engineers-Technical
liateSymposium, Akron (O
hio), October 20, 1977-1 It was reported that the dilithium compound content of the dilyticum catalyst was only 64-, and its difunctionality was highly questionable. In addition, dilithium catalyst 4 (Example 1a of No. 4I & 11850-16688) obtained by the reaction of reduced-butyllithium and m-diisopropenylbenzene],
It is also known that this can be further stabilized by low polymerization of isoprene (US Pat. No. 3,903,168 or Macromolecules, Vol. 10, 2).
87 pages, published in 1977), the former was simply obtained as an intermediate for obtaining trilithium, and the latter was pointed out to have insufficient ll12 functionality. (Makromol, Chem,,
Volume 179, page 551, published in 1978 or Pol
ymar, Volume 20.

(Page 1129, published in 1979). Moreover, it requires low concentration to be used as a catalyst, and its stability requires storage stabilization by low polymerization of isoprene.
The reaction product of 5ec-butyllithium and m-diisopropenylbenzene itself was only insufficient.

As shown above, the dilithium catalysts of the prior art have imperfect concentrations, purity, and stability, are soluble in hydrocarbon solvents, and have concentrations that can be used industrially as polymerization catalysts. The development of a dilithium catalyst having high purity and stability, and a method for easily producing the same, has been a long-standing challenge in the art.

The inventors of the present invention have completed the present invention as a result of extensive research into the development of the above-mentioned dilithium catalyst.

The dilithium catalyst of the present invention has the following general formula (A or 11
It is characterized in that the dilithium compound represented by (B) contains 90 mole or more of lithium using the analytical method of the present invention.

R, Li tA) (where R1 and R, Fi are alkyl hydrocarbon groups having 3 to 5 carbon atoms, birds and R4ll1 methyl groups or ethyl groups, birds are hydrogen or methyl groups, preferably islands and R8 is a butyl group or a pentyl group, R8 is a methyl group or an ethyl group, and R8 is hydrogen.More preferably,
When R8 and R3 are a 2-methylbutyl group, - and Hiki are a methyl group, and - is hydrogen, and the above (B)
Yoshi (4) is more preferable. This is due to the ease of manufacturing the scissor dilithium catalyst described below.

The dilithium catalyst of the present invention has a dilithium compound containing at least 990 moles of lithium using the analysis method of the present invention described below, that is, 990 moles or more of lithium per lithium, that is, 990 moles or more of all the chicum atoms contained in the dilithium catalyst. 0 mol or more is required to be included as a constituent of the above-mentioned dilithium compound. If the content of the dilithium compound is less than 90 mole, not only will the solubility in hydrocarbon solvents be insufficient and the storage stability will decrease, but also polylithium or unreacted organic matter will be present in the dilithium compound together with the dilithium compound. Therefore, the polymerization reaction of conjugated dienes or aromatic alkenyl compounds using such catalysts results in an increase in the content of dilithium chloride (poison chloride). However, it is not undesirable that side reaction products such as star-shaped polymers and cross-linked polymers are formed, making it difficult to control the molecular weight of the resulting polymer, but also undesirably increases the viscosity of the living polymer. Furthermore, when used in the production of ABA block polymers, the presence of organolithium compounds in the dilithium catalyst results in the formation of AB-type polymers, which adversely affect tensile strength.

For the above reasons, the dilithium catalyst used in the present invention needs to contain at least 90 mol of the dilithium compound, and more preferably ijq s mol or more of the dilithium compound.

The content of the dilithium compound used in the present invention is analyzed as follows. That is, after deactivating the dilithium catalyst with water in an inert gas atmosphere, gel permeation chromatography of the components contained in the organic layer is performed.

The column used for this removal has an exclusion limit molecular weight of 1000 to 5.
000 is preferable, and an ultraviolet absorbance needle (254 nm) is used as a detector. Using a column calibration curve using polystyrene as a standard sample, it is possible to identify the oligomer components in the water-deactivated catalyst and analyze the ratio of each component based on their molecular weights.

Furthermore, unreacted organolithium compounds contained in the catalyst (both water-deactivated samples and active samples) are analyzed separately by gas chromatography. Therefore, using the above analytical values, it is possible to calculate the true content of dilithium compounds.

The content of the dilithium compound analyzed and calculated in this way has a more direct and accurate value than the above-mentioned conventional analysis method. For example, the results of using this technique to analyze various known catalysts, the intermediates (dilithium catalysts before stabilization by in-pre/low polymerization) of the aforementioned US Pat. It was only about 70 molti, about 45 molti.

The dilithium catalyst of the present invention is characterized by being soluble in hydrocarbon solvents at high concentrations. Hydrocarbon solvents include commonly known aliphatic or aromatic hydrocarbons, such as n-hexane, n-pentane, n-hebutane, n-octane, isooctane, cyclopentane, cyclohexane, benzene, toluene, ethylbenzene. , flobylbenzene is preferred, and its concentration is lithium atoms/
The amount expressed as a hydrocarbon solvent is preferably 0.3 mol/liter or more. In general, dilithium catalysts with too low concentrations are undesirable because they have insufficient storage stability and require a large capacity for use, which may cause problems when added to the polymerization system, for example.

The dilithium catalyst of the present invention is characterized by the coexistence of a tertiary monoamine. Preferred tertiary monoamines include trimethylamine, triethylamine, tri-n
-propylamine, N,N'-dimethylaniline, N,
Examples include N-diphenylmethylamine. Most preferred is triethylamine. Further, it is preferable that the amount of the tertiary monoamine present exceeds at least 0.5 times the mole of lithium atoms, and is an amount that satisfies the condition of the following formula (C).

k y > kg x −o, s --------
-(C) (where xIfi is the molar ratio of tertiary monoamine to lithium atoms, y is the concentration expressed as tertiary monoamine/hydrocarbon: unit mole/liter) an appropriate amount of 5
The coexistence of grade monoamines has the effect of significantly improving the storage stability of dilithium catalysts, and its amount is regulated by the molar ratio to lithium atoms and the desired concentration in the hydrocarbon solvent; outside this range, the storage stability is In addition, there are no regulations regarding the production of dilithium catalysts, which will be described later.

The aromatic alkenyl hydrocarbon used in producing the dilithium catalyst of the present invention is represented by the following formula (A') or Fi
It has the structure (B').

i (A') (B') Here, Tori and Hen are methyl groups or ethyl groups, and Hen is hydrogen or methyl groups, and such compounds include m-diisopropenylbenzene, p-diimpropenylbenzene, 1
．． 3-bis(1-ethylethynyl)benzene, 1.4-
Bis(1-ethylethynyl)benzene and the above-mentioned methyl enzyme derivatives are mentioned.

When the above molecule and RS are hydrogen, it is difficult to oligomerize the aromatic alkenyl hydrocarbon, and when RS and RS are alkyl groups having 3 or more carbon atoms, due to the bulkiness of the substituent. , the reaction activity becomes too small. Furthermore, the m-isomer is more preferable than the p-isomer, because the p-isomer forms a resonance structure between the living anion and the aromatic ring, which stabilizes the m-isomer. This is thought to be because they cannot form such a structure and can be easily activated.

In addition, as an organic lithium compound, general formula Tori-Li (
RsFi alkyl group) can be used. Such examples include n-butyllithium,
Mention may be made of butyllithium, tert-butyllithium, 2-methyl-propyllithium, ethyllithium, propyllithium, i-propyllithium, but the preferred organolithium compound is the formula -butyllithium.

The amount of the organolithium compound used in the present invention is preferably strictly twice the molar amount of the aromatic alkenyl hydrocarbon, but may be increased or decreased by 5 degrees depending on the case. When the amount of the organolithium compound significantly exceeds 2 times the mole of the aromatic alknyl hydrocarbon, for example, when using 2.5 times the mole or more, unreacted organic chlorine 9
If the amount of the compound becomes too large or the amount used is extremely small, for example, if i;jl is 5 times the mole or less,
Oligomerization of aromatic alkenyl hydrocarbons becomes predominant, making it impossible to achieve the object of the present invention.

As the reaction solvent of the present invention, generally known aliphatic or aromatic hydrocarbons can be used. Examples of such are n-hexane, n-heptane, n-octane, isooctane, cyclopentane, cyclohexane, benzene, toluene, ethylbenzene, propylbenzene, and any two of these before any more Mixed solvents can also be used, but preferably n-
These are hexane, cyclohexane, and benzene.

The concentration of the reaction raw material in these hydrocarbon solvents is preferably 0.3 mol/liter or more based on lithium atoms/hydrocarbon solvent. If the concentration is lower than this, the high concentration and high purity dilithium catalyst of the present invention cannot be obtained.

As additives preferably used in the present invention, c.
Examples include tertiary monoamines such as trimethylamine, triethylamine, tri-n-propylamine, N,N'-dimethylaniline, and N,N-diphenylmethylamine. When using tertiary diamines such as N, N, N', N'-tetramethylethylenediamine and dibiperidinoethane, the coordination with 5 and Li ions is too strong due to the chelating action of the amino group, making it undesirable. Gives no results. Furthermore, when ethers such as diethyl ether and tetrahydrofuran are used as additives, undesirable reactions such as metalation occur due to the strong polar action of oxygen atoms. Furthermore, when these highly polar additives are used, they have a significant influence on the microstructure of the conjugated diene polymer, and it is often difficult to control it. Therefore, depending on the target polymer,
It is preferable to use a compound that tends to have undesirable effects and is as weakly polar as possible.

Particularly preferred in the present invention is triethylamine.

Furthermore, the amount of tertiary monoamine used as an additive is characterized by satisfying the following formula (C).

ky > kgx −0,5・・・・・・・・・ (C
) (In the formula, X represents the molar ratio of the tertiary monoamine to 1 mole of the organolithium compound, and y represents the concentration of the tertiary monoamine contained in the dilithium compound; unit mole/liter.) Amount of additive is used in an amount exceeding at least 0.5 times the mole of the organocutimum compound, although it varies depending on the degree of strength as a Lewis base. When the amount is 0.5 times the mole or less, the amount of dilithium compound formed by the reaction between the organolithium compound and the aromatic alkenyl hydrocarbon is significantly reduced, and the amount of dilithium compound formed as a concerted reaction is reduced.
It becomes difficult to suppress the production of gum compounds. Furthermore, even when the molar ratio of the additive to the organic cut 9 compound exceeds 0.5, the content of the dilithium compound differs depending on the additive concentration. If the additive concentration is too low, the effectiveness of the additive in contributing to the formation of dilithium compounds is significantly reduced. Therefore, in order to obtain the desired dilithium catalyst containing 90 moles or more of a dilithium compound, each additive used must contain a certain concentration or more for each K molar ratio of the additive to the organic lithium compound. It requires that. In the present invention, the relationship can be expressed by the above equation (0, preferably !ogx + 0.
It is expressed as S>ky>logx-0,5.

Furthermore, when triethylamine is used as the 6th class monoamine, in order to achieve the object of the present invention, it is preferable that K is reacted for a certain period of time or longer depending on the amount of triethylamine added and the reaction temperature. Generally speaking, the amount of triethylamine used is large, and
The higher the reaction temperature, the shorter the time required for the reaction. However, if the amount of triethylamine added is too large, it is generally not preferred in view of the influence it may have on the microstructure of the polymer.

In addition, if the reaction temperature is too high, side reactions such as oligomerization of the aromatic alkenyl hydrocarbon become predominant, and it is also undesirable because it causes deactivation of the group.

In the present invention, the preferable conditions that the reaction time satisfies are: x f''T dt >1000 ---
-(E) (where x#'i is the molar ratio of triethylamine to 1 mole of the organolithium compound, T is the reaction temperature; the unit is 0 K, and t is the reaction time; the unit is hr). shall be.

In the above formula (E), when the reaction temperature T is constant,
Equation (E) can be further rewritten as the following equation (F'), that is, the reaction time t is the amount of triethylamine added,
The effects of the present invention are significant when the relationship of formula (g) above is satisfied between the reaction temperature T and the reaction temperature T.

The dilithium catalyst thus obtained is completely soluble in hydrocarbon solvents, has high concentration, high purity, and high stability, and is suitable for use as is or for further underpolymerizing isoprene. It can be further stabilized and used alone, or it can be used in combination with other polyfunctional polylithium catalysts. When used alone, the block copolymer produced can be widely used as a thermoplastic polymer or resin for injection molded products such as tires, footwear, or containers, compression molded products such as backings, plates, and sheets, or adhesives and paints. It is also useful as a component of coating agents. In addition, polymers with functional groups at both ends are subjected to various treatments such as hydroxylation, carboxylation, and maleation to introduce polar groups and are used for the purpose of imparting crosslinkability. are useful as prepolymers for a variety of applications, such as hydroxylation followed by reaction with incyanate to produce polycretanes.

The thermoplastic styrene-butadiene copolymer obtained using the catalyst of the present invention has extremely excellent breaking strength. Furthermore, even when mixed with other polyfunctional poly-17 lithium catalysts depending on the purpose, the resulting copolymer has desired tear strength and breaking strength.
Furthermore, when the catalyst of the present invention is used to produce a styrene-butadiene copolymer and the styrene content is high, it is also possible to obtain a resinous copolymer with high impact strength.

Hereinafter, the present invention will be explained in more detail with reference to Examples.

Example 1 m-diisoprobenylbenze 7 kA Macromo
lecules.

It was prepared by the method described in Tsuchimi (2), 287 (1977).

Also, the formula -butyllithium is given by J, Amer, Chem
,Soc,.

91.6562 (1969) fC in a cyclohexane solvent at a concentration of 1.2 to 2.5N.

1oos with a magnetic stirrer and a rubber seal
A g7 glass bottle was purged with nitrogen, and 42.7 mg (65.2 mmol) of 1.48N butyllithium was added to it.
Triethylamine 8.7 mg (63.2 mmol)
, and 6.6 d of cyclohexane were introduced at 2Q°C and mixed by stirring in the bottle. Furthermore, m-diisopropenylbenzene 51 (51.6 mmol) was added dropwise from a T-syringe over a period of 1 hour. The reaction mixture turned into a deep red clear solution over time and no precipitate was observed. m
- After the completion of the dropwise addition of diisopropenylbenzene, sampling was carried out as follows while stirring was continued. That is, 10 g of the reaction solution was deactivated with water in a separate bottle purged with nitrogen, and the organic layer was subjected to gel permeation chromatography using chloroform as an eluent. The components were measured. In addition, the amount of butyl lithium was determined by gas chromatography in the gas phase. The results are shown in Table 1.

Examples 2 to 5, Comparative Examples 1 to 4 The same operation as in Example 1 was performed except for changing the concentration of triethylamine and the reaction temperature. The conditions and results are shown in Tables 1 and 2.

Examples 6 and 7 Except for replacing /dwt-butyllithium with i-propyllithium in Example 6, replacing 1jsec-butyllithium with tert-butyllithium in Example 7, and changing the concentration of triethylamine. The same operation as in Example 1 was performed. The conditions and results are shown in Table 1.

Comparative Example 5 The same procedure as in Example 1 was carried out except that m-diisopropenylbenzene was added dropwise at -20°C for 2 hours and then the reaction temperature was further raised to 30°C. The conditions and results are shown in Table 2.

Comparative Examples 6 and 7 The same operation as in Example 1 was carried out, except that in Comparative Example 6, diethyl ether was used instead of triethylamine, and in Comparative Example F, FiN, N, N', N' -)limethylethylenediamine was used. The zero conditions and results are shown in Table 2.

Comparative Example 8.9 The same operation as in Example 1 was carried out, except that in Comparative Ha #9, m-divinylpenze/ was used instead of Fim-diisopropenylbenzene, and the concentration of triethylamine and reaction conditions were changed. The conditions and results are shown in Table 2.

From Tables 1 and 2, the dilithium catalyst obtained by the production method of the present invention has a high concentration, the content of dilithium compounds is 90 molti or more, and it has excellent solubility and stability. It can be seen that

Using the dilithium catalysts produced in Examples 1 and 2.4 and Comparative Examples 2 and 5.7, in a bottle purged with nitrogen under the conditions shown in Table 3, in 602 butadiene and n-hexane,
Polymerization was carried out at 60°C for 1 hour, and styrene 409 was further added thereto, followed by polymerization at 70°C for 2 hours. The obtained block copolymer was deactivated with methanol, vacuum-dried at room temperature for 3 days, and the physical properties were evaluated. The evaluation results are shown in Table 3. The dilithium catalyst of the present invention has favorable polymerization activity, and the resulting block copolymer has extremely excellent physical properties, such as
It can be seen that it has a high tensile strength.

[Brief explanation of the drawing]

FIG. 1 is a GPC chart of each sample obtained in Example 1, a, immediately after the start of the reaction, b, 48 hours after the start of the reaction, and C, 48 days after the start of the reaction. Figures 2 and 5 show the G of the sample obtained 48 hours after the reaction in Comparative Example 2 and Comparative Example Hc, respectively.
This is a PC chart. Analyzer: 9 Otters Model 244 High performance liquid chromatograph detector: Waters Model 440 (UV-254am)
Kara b: 7.4 ml i, d,
X 50 cWl (M, Jim, = 3400
) Eluent: Chloroform Flow rate: 10 wIt/Maro procedural amendment January 51, 1980 Commissioner of the Japan Patent Office Kazuo Wakasugi 1 Indication of the case Patent application No. 18150/1982 2 Name of the invention High concentration and high concentration with excellent storage stability Purity dilithium catalyst and its manufacturing method 3 Relationship with the case of the person making the amendment / Patent applicant (OOS) Asahi Kasei Kogyo Co., Ltd. 4 Agents 5F, Toranomon Sangyo Building, 2-29 Toranomon, Minato-ku, Tokyo Subject of amendment 6 The description of the details of the amendment shall be amended as follows. (1) On page 5, line 17, "It is classified into three types." is corrected to "There are five types." (2) On page 6, lines 1-2, "dihalogen alkanes" is corrected to "dihaloalkane." (3) "Reaction of divinylbenzene" on page 6, line 18 is corrected to "reaction with divinylbenzene." (4) Correct "dilithium content" in the 12th negative 7th line to "content of dilithium compound." (5) On page 14, lines 2 to 5, "does not exist." is corrected to "undesirable." (6) [1,5-bis(1-ethylethynyl)benzea Jt"
1,5-bis(1-ethylethynyl)benzene"to be corrected. (7) “t,4-bis(1-ethylethynyl)benzene” in lines 5-4 from the bottom of page 14.
1. Correct 4-bis(1-ethylethynyl)benzene. (8) On page 21, line 5, "other polyfunctional polylithium catalysts" is corrected to "mono- or other polylithium catalysts." (9) On page 28, line 4, "in n-hexane" is corrected to "in t-cyclohexane."鵠 On page 2B, lines 7 to 8, ``It was submitted for physical property evaluation.'' is corrected to ``It was submitted for physical property evaluation.'' αυ “] I [2) 0 Yuki 04- BHPOJ [*2) 0” in the margin of Table 5 on page 29
80. - Correct as BHPOJ. αri On page 30, line 15, [10Bg/ll1lJ is corrected to “1.Osg/ijJ.

Claims (1)

[Scope of Claims] 111 Dilithium characterized by containing a dilithium compound represented by the following general formula (4) or ti (B) in an amount of 9Ω or more per lithium using the analysis method of the present invention. catalyst. (A) (B) (In the formula, R1 and R3 represent an alkyl hydrocarbon group having 3 to 5 carbon atoms, - and a, Fi methyl group or ethyl group, Rsti hydrogen or methyl group.) (2) General formula srt, R1 and R3 are butyl or pentyl groups, - and Hiki are methyl or ethyl groups, and R11 is a hydrogen tank.
Dilithium catalyst as described in section. (3) The general formula is (4) and % R1 and R8
The dilithium catalyst according to claim 1, wherein is a 2-methylbutyl group, - and - are a methyl group, and R1 is hydrogen. (4) Claims 1 to 5, wherein the dilithium catalyst is soluble in a hydrocarbon solvent, and its performance is 0.3 mol/liter or more expressed as lithium atoms/hydrocarbon solvent. Dilithium catalyst as described. (5) The dilithium catalyst according to claim 4, wherein a tertiary monoamine that exceeds at least 0.5 moles of lithium atoms and satisfies the conditions of the following formula (C) is present in the hydrocarbon solvent. kz y >1#x −0,5・・・・・・・・・
(C1 (in the formula, x#i molar ratio of 5th-class monoamine to cut 9 atoms, yFi tertiary monoamine/degree expressed as hydrocarbon solvent; unit mol/liter) (6) The following general formula (A') Also, when 1 mole of the aromatic alkenyl hydrocarbon represented by ti (B') is reacted with twice the mole of the organolithium compound represented by the following general formula (B) in a hydrocarbon solvent, The general formula (2
) A method for producing a dilithium catalyst, characterized in that the concentration of the organolithium compound represented by (1) is 0.5 mol/liter or more expressed as lithium atoms/hydrocarbon solvent. 1 (Mu') (B') ■)
(In the formula, ed and nagi represent a methyl group or an ethyl group, ed represents a water mass or a methyl group, and R represents an alkyl hydrocarbon group having 2 to 4 carbon atoms.) (7) At least one of lithium metal in a hydrocarbon solvent The method for producing a dilithium catalyst according to claim 6, wherein the tertiary monoamine exceeds 0.5 times the mole and satisfies the conditions of the following formula (C): k@Y > klgx -0,5- −−−−、−、、
(Cy) (wherein, the molar ratio of XFi S-class monoamine to lithium atoms, y is the concentration expressed as 5th-class monoamine/hydrocarbon solvent; unit mol/liter) (8> The 5th-class monoamine is more than triethylamine. A method for producing a dilithium catalyst according to claim 7, which satisfies the conditions of the following formula (to): xf Tdt > 100 Q - (E) (wherein, The molar ratio of triethylamine to 1 mole of the organolithium compound described in Section 1, T is the reaction temperature;
The unit is 0K, and t is the reaction time; the unit is hr. ) (9) Aromatic alkenyl hydrocarbon is m-diimpropenylbenzene% organic') tiumka wt-7'chirrichi9
A method for producing a dilithium catalyst according to any one of claims 6 to 8, wherein