JP2000281774A - Production of polyphenylene ether - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a polyphenylene ether at a high efficiency by oxidation polymerizing a phenolic compound under conditions in which the phenolic compound is present in a specified or higher concentration in the reaction system, and the copper compound and bromine compound in a copper-amine catalyst are present each in a specified or smaller amount in the reaction system. SOLUTION: The copper-amine catalyst comprises a copper compound, a bromine compound, a diamine compound of the formula a tertiary monoamine, and a secondary monoamine. The oxidation polymerization is performed under conditions in which the concentration of the phenolic compound used is at least 23 wt.% based on the entire feed mixture, the copper compound of the catalyst component is present in an amount not exceeding 5 mmol per kg of the feed mixture, and the bromine compound of the catalyst is present in an amount not exceeding 20 mmol (in terms of the bromine atoms) per kg of the feed mixture. Further, it is desirable that the diamine is present in the reaction mixture in an amount not exceeding 10 mmol per kg of the feed mixture. In the formula, R1, R2, R3, and R4 are each H or a 1-6C linear or branched alkyl, provided that all of them are not H simultaneously, and R5 is a 2-5C linear or methyl-branch-containing alkylene.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an improved, efficient and low-cost method for producing polyphenylene ether.

[0002]

2. Description of the Related Art As a polymerization catalyst used in the production of polyphenylene ether by oxidative polymerization of a phenolic compound, many combinations of a copper compound and various amines have been proposed since JP-B-36-18892. Has been proposed. That is, there have been proposed various kinds of copper compounds and halides cooperating therewith, selection of amines from primary amine, secondary amine and tertiary amine, and various proposals such as monoamine, diamine and polyamine. Have been.

For example, as old as US Pat. No. 3,306,875,
Nos. 3,344,116 and 3,432,466 disclose a method using a catalyst system of a copper compound and a tetraalkyl-type diamine such as N, N, N ', N'-tetramethyl-1,4-butanediamine. JP-A-17075 and JP-B-52-17076 also propose a combination of a copper compound with a tetraalkyl-type diamine and an iodine compound.

Further, Japanese Patent Publication No. 58-53012 and Japanese Patent Publication No. 5
No. 9-23332 discloses a combination of a copper compound, a bromine compound and a tertiary amine such as N, N′-di-tert-butylethylenediamine and n-butyldimethylamine, and a method of combining the tertiary amine with N-di-n. -A method comprising a combination with a secondary monoamine such as -butylamine has been proposed. JP-A-64-33131 discloses a copper compound and a secondary aliphatic amine or a secondary aliphatic amine and an aniline having a special structure and N, N, N ', N'-tetramethyl 1,3-. A highly active process with improved water resistance by using diamino (substituted or unsubstituted) propane and bromine or chlorine compounds is disclosed.

In order to reach a desired molecular weight in a limited time by a conventional method represented by Japanese Patent Publication No. 58-53012, a phenolic compound (monomer:
Hereinafter, the phenolic compound is abbreviated as a monomer), and requires a specific amount of a catalyst. That is, the amount of the catalyst with respect to the monomer in order to maintain the activity is specified.

[0006]

It is essential to increase the monomer concentration from the viewpoint of efficient production. However, in the conventional method, the amount of the catalyst relative to the monomer is important to maintain the activity. It was thought that the amount of catalyst had to be increased in proportion to That is, an increase in the monomer concentration leads to an increase in the catalyst concentration, which leads to an undesirable reaction and an increase in the load of the step of removing the catalytic metal component in the polymerization mixture.

The present invention solves these conventional problems,
An object of the present invention is to provide a method for producing a polyphenylene ether with high efficiency.

[0008]

Means for Solving the Problems The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, surprisingly, the poly (phenylene ether) was obtained by oxidative polymerization of a monomer in the presence of a copper-amine catalyst. In the production method, the concentration of the phenolic compound on the basis of the total charged mixture was 23.
wt% or more and contains a copper compound and a bromine compound as specific components in a part of the catalyst, and the amount of the copper compound as the specific component in terms of copper atoms does not exceed 5 mmol per 1 kg of the whole mixture. The present inventors have found that a highly efficient production of polyphenylene ether can be achieved by polymerizing a bromine compound as a specific component in a bromine atom-converted amount of not more than 20 mmol and not more than a specific amount. Was.

Preferably, the catalyst used in the present invention comprises (a) a copper compound, (b) a bromine compound, and (c) a compound represented by the following formula (1):

[0010]

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[0011] (wherein, in _{R 1, R 2, R 3} , R 4 are independently hydrogen, a linear or branched alkyl group having from 1 to 6 carbon atoms, are not all simultaneously hydrogen .R ₅ is A straight-chain or alkylene group having a methyl branch having 2 to 5 carbon atoms), (d) a tertiary monoamine, and (e) a catalyst comprising each component of a secondary monoamine. As long as the amount of copper atoms of the catalyst component (a) per 1 kg of the total charged mixture does not exceed 5 mmol, the amount of bromine atoms of the catalyst component (b) per 1 kg of the total charged mixture is 20 or less.
In the case where the amount does not exceed mmol, the present invention is more effective when the amount of the diamine molecule of the catalyst component (c) per 1 kg of the whole charged mixture does not exceed 10 mmol.

In the present invention, 0.1% is contained in the whole charged mixture.
It is preferable to add a tetraalkylammonium salt compound or a polyethyleneglycol group-containing alkylamine or a polyethyleneglycol group-containing alkylammonium salt compound in a range not exceeding 1% by weight, since the effect of the present invention can be further enhanced.

Hereinafter, the present invention will be described in detail.

In the present invention, in a method for producing a polyphenylene ether by oxidative polymerization of a monomer in the presence of a copper-amine catalyst, in order to reach a desired molecular weight within a limited time, a method based on the total charged mixture is used. Keep the concentration of the specific component of the catalyst constant and the monomer concentration at 2
It is necessary to polymerize at 3 wt% or more. When the monomer concentration is lower than 23% by weight, the specific component of the catalyst for reaching the desired molecular weight within a limited time becomes proportional to the monomer, and the present invention is not effective. The region where the concentration of the specific component of the catalyst is constant on the basis of the whole charged mixture is effective in the region where the monomer concentration is 23 wt% or more.
That is, in the monomer concentration region of the present invention, it is not necessary to increase the specific catalyst component in proportion to the monomer in order to reach a desired molecular weight within a certain limited time, and the concentration of the specific catalyst component in the whole charged mixture is reduced. It just needs to be constant.

The monomer (phenolic compound) used in the present invention is a compound having a structure represented by the following formula (2).

[0016]

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(Wherein R ₆ is an alkyl group, a substituted alkyl group, an aralkyl group, a substituted aralkyl group, an aryl group, a substituted aryl group, an alkoxy group, a substituted alkoxy group, and R ₇ is the same as defined for R ₆ And R ₈ may be hydrogen in addition to the same groups as defined for R _7. ) Examples of the compound include, for example, 2,6- Dimethylphenol, 2,3,6-trimethylphenol, 2-methyl-
6-ethylphenol, 2,6-diethylphenol,
2-ethyl-6-n-propylphenol, 2-methyl-6-chlorophenol, 2-methyl-6-bromophenol, 2-methyl-6-isopropylphenol,
-Methyl-6-n-propylphenol, 2-ethyl-
6-bromophenol, 2-methyl-6-n-butylphenol, 2,6-di-n-propylphenol, 2-
Ethyl-6-chlorophenol, 2-methyl-6-phenylphenol, 2,6-diphenylphenol, 2,
6-bis- (4-fluorophenyl) phenol, 2-
Methyl-6-tolylphenol, 2,6-ditolylphenol and the like can be mentioned. These compounds may be used alone or in combination of two or more. Also, a small amount of phenol, o-cresol, m-cresol, p-
Cresol, 2,4-dimethylphenol, 2-ethylphenol and the like may be substantially contained. Of these phenolic compounds, 2,6-dimethylphenol is particularly industrially important.

The catalyst which can be used in the present invention is a copper-amine catalyst. Various copper-amine catalysts can be used, but any catalyst system should have a phenolic compound concentration of 23 wt% or more based on the whole charged mixture and contain a copper compound as a specific component in a part of the catalyst,
It is necessary to carry out the polymerization in such a manner that the amount of the copper compound as the specific component in terms of copper atoms does not exceed 5 mmol per 1 kg of the whole charged mixture. In other words, the more active the catalyst, the more effectively the present invention works.

Suitable catalysts include (a) a copper compound, (b) a bromine compound, and (c) a compound represented by the following formula (1):

[0020]

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(Wherein R ₁ , R ₂ , R ₃ , and R ₄ are each independently hydrogen, a linear or branched alkyl group having 1 to 6 carbon atoms, and not all are hydrogen at the same time. R ₅ is A straight-chain or alkylene group having a methyl branch having 2 to 5 carbon atoms), (d) a tertiary monoamine, and (e) a secondary monoamine.

The most important amount of the catalyst component specified with respect to the whole charged mixture is the amount of copper atoms contained in the copper compound. The type of copper compound is not critical. The present invention is effective when the amount of copper atoms of the copper compound as a catalyst component per 1 kg of the whole charged mixture does not exceed 5 mmol.

As the copper compound, a cuprous compound, a cupric compound or a mixture thereof can be used. As the cupric compound, for example, cupric chloride, cupric bromide,
Cupric sulfate, cupric nitrate and the like can be exemplified. Examples of the cuprous compound include cuprous chloride, cuprous bromide, cuprous sulfate, cuprous nitrate, and the like. Of these, particularly preferred metal compounds are cuprous and cupric compounds such as cuprous chloride, cupric chloride, cuprous bromide and cupric bromide. These copper salts are oxides,
It may be synthesized at the time of use from a corresponding halogen or acid with a carbonate, hydroxide or the like.

The next important factor in the amount of catalyst component specified relative to the total charge mixture is the amount of bromine atoms in the bromine compound.

The amount of bromine atoms in the bromine compound with respect to the total charged mixture is determined based on the total charged mixture 1 in the catalyst system.
The present invention works effectively when the amount of bromine atoms in the catalyst component (b) per kg does not exceed 20 mmol.

The amount of the diamine compound with respect to the total charged mixture is 1 kg in the catalyst system.
The present invention works effectively when the amount of the diamine compound of the catalyst component (c) does not exceed 10 mmol per unit.

The type of bromine compound is not critical. Conventionally known bromine compounds can be used. For example, hydrogen bromide,
Sodium bromide, potassium bromide, tetramethylammonium bromide, tetraethylammonium bromide and the like. These can be used as an aqueous solution or a solution using an appropriate solvent. These bromine compounds may be used alone or as a combination of two or more.

The type of the diamine (c) preferably used is not particularly limited as long as it has the structure represented by (1).

Among the catalyst systems preferably used, the amounts of the tertiary monoamine (d) and the secondary monoamine (e) relative to the total raw material mixture are not particularly limited. Even in the case of the monomer concentration region of 23 wt% or more in the present invention, the reaction may be performed in proportion to the monomer, or the amount with respect to the entire raw material mixture may be fixed.

The tertiary monoamine is an aliphatic tertiary amine including an alicyclic tertiary amine. For example, trimethylamine, triethylamine, tripropylamine, tributylamine, triisobutylamine, dimethylethylamine, dimethylpropylamine, allyldiethylamine, dimethyl-n-butylamine, diethylisopropylamine, N-methylcyclohexylamine and the like can be mentioned. These tertiary monoamines may be used alone or as a combination of two or more. The amount of these used is not particularly limited and not important,
Usually when used in proportion to monomers, it will range from 0.1 to 10 moles per 100 moles of monomer.

The kind of the secondary monoamine is not particularly limited, but examples thereof include dimethylamine, diethylamine, di-n-propylamine, di-i-propylamine, di-n-butylamine, di-i-butylamine, -T-butylamine, dipentylamines, dihexylamines, dioctylamines, didecylamines, dibenzylamines, methylethylamine, methylpropylamine, methylbutylamine, cyclohexylamine and the like. Examples of the N- (substituted or unsubstituted phenyl) alkanolamine include N-phenylmethanolamine, N-phenylethanolamine, N-phenylpropanolamine, and N- (m-methylphenyl)
Examples thereof include ethanolamine, N- (p-methylphenyl) ethanolamine, N- (2 ′, 6′-dimethylphenyl) ethanolamine, and N- (p-chlorophenyl) ethanolamine. Examples of the N-hydrocarbon-substituted aniline include N-ethylaniline, N-butylaniline, N-methyl-2-methylaniline, and N-methyl-aniline.
Examples thereof include 2,6-dimethylaniline and diphenylamine, but are not limited to these examples. These secondary monoamine compounds may be used alone or as a combination of two or more. The amount used is not particularly limited or critical, but if carried out in proportion to the monomers, could range from 0.05 mol to 15 mol per 100 mol of monomer.

In the present invention, 0.1% is contained in the whole charged mixture.
It is preferable to add a tetraalkylammonium salt compound or a polyethyleneglycol group-containing alkylamine or a polyethyleneglycol group-containing alkylammonium salt compound in a range not exceeding 1% by weight, since the effect of the present invention can be further enhanced.

Examples of such compounds are represented by the following formula (3):
It has a structure represented by (4) or (5).

[0034]

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(Wherein R ₉ , R ₁₀ , R ₁₁ and R ₁₂ are each independently a linear or branched alkyl group having 1 to 22 carbon atoms, and X is a paired anion)

[0036]

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[0037] (wherein, R ₁₃ represents a linear or branched alkyl group having a carbon number of 1 to 22, R ₁₄ in addition to the groups defined in _{R 13 - (CH 2 CH 2} O) n-H [ n is an integer of 1 to 40], and R ₁₅ is-(CH ₂ CH
₂ O) n-H [n is a group represented by 1 to 40]

[0038]

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(Wherein R ₁₆ and R ₁₇ are each a carbon number of 1 to 22)
R ₁₈ is a group represented by — (CH ₂ CH ₂ O) n—H [n is an integer of 1 to 40] in addition to the group defined for R _16. R ₁₉ is-
_{(CH 2 CH 2 O) n} -H [n is 1 to 40 integer] is a group represented by, X is an anion forming a pair) such compounds, dispersing the water generated during the polymerization It is preferable to use in the method of the present invention because it is effective for retaining and maintaining activity.

The solvent used in the method of the present invention is not particularly susceptible to oxidation as compared with the monomer to be oxidized, and has little reactivity to various radicals which are considered to be formed in the course of the reaction. Although not limited, those which dissolve low molecular weight phenolic compounds and dissolve part or all of the catalyst mixture are preferable. Examples of such solvents include, for example, benzene, toluene,
Examples include aromatic hydrocarbons such as xylene and ethylbenzene, halogenated hydrocarbons such as chloroform, methylene chloride, 1,2-dichloroethane, trichloroethane, chlorobenzene, dichlorobenzene and trichlorobenzene, and nitro compounds such as nitrobenzene. These can be used as good solvents for the polymer. Alcohols such as methanol, ethanol, propanol, butanol, benzyl alcohol, and cyclohexanol; aliphatic hydrocarbons such as pentane, hexane, heptane, cyclohexane, and cycloheptane; ketones such as acetone and methyl ethyl ketone; ethyl acetate; and ethyl formate. And the like, esters such as tetrahydrofuran and diethyl ether, amides such as dimethylformamide, sulfoxides such as dimethylsulfoxide, and water. One or more of the solvents can be further mixed and used if necessary.

Examples of the solvent often used include a single solvent of an aromatic hydrocarbon such as toluene and xylene, and a mixed solvent containing an alcohol such as methanol and ethanol.

By selecting the ratio of a good solvent and a poor solvent to polyphenylene ether, which is a polymer obtained by oxidative polymerization of a phenolic compound, a solution polymerization method can be used, and by increasing the ratio of a poor solvent, the reaction can be improved. As the process proceeds, a precipitation polymerization method in which the polymer is precipitated as particles in the reaction solvent is also provided.

The present invention can be applied to polymerization methods such as a batch polymerization method, a continuous polymerization method, a solution polymerization method, and a precipitation polymerization method.

In the polymerization reaction system, alkali metal hydroxides, alkaline earth metal hydroxides and alkali metal alkoxides as strong alkalis having an effective cocatalytic action depending on the catalyst, and magnesium sulfate for dehydration. , Calcium chloride and other neutral salts, zeolites and the like can also be added.

Regarding the polymerization reaction temperature, if the temperature is too low, the reaction hardly proceeds, and if it is too high, the catalyst may be deactivated. Therefore, the polymerization is carried out at a temperature of 0 to 80 ° C., preferably 10 to 70 ° C. preferable.

As the oxygen in the oxidative polymerization of the present invention, in addition to pure oxygen, those mixed with an inert gas such as nitrogen at an arbitrary ratio, and air can be used. The pressure in the system during the reaction is usually at normal pressure, but it can be used under reduced pressure or under increased pressure as needed.

The post-treatment method after the completion of the polymerization reaction is as follows.
There is no particular limitation. Usually, an acid such as hydrochloric acid or acetic acid, or ethylenediaminetetraacetic acid (EDTA) and a salt thereof, nitrilopolyacetic acid and a salt thereof are added to the reaction solution to deactivate the catalyst. The polyphenylene ether can be recovered by a simple operation of washing with a solvent which does not dissolve the polymer and drying.

[0048]

BEST MODE FOR CARRYING OUT THE INVENTION Next, the present invention will be described in more detail by way of examples using 2,6-dimethylphenol as a monomer, but the present invention should not be limited by these examples.

The viscosity of polyphenylene ether (ηs
p / c) is a value measured using a Ubbelohde viscometer at 30 ° C. using a 0.5 g / 100 ml chloroform solution of the polymer. The unit is represented by dl / g.

[0050]

EXAMPLES The general procedure in the polymerization examples is described below.

Each catalyst component and a part of toluene are added to a 4 liter jacketed glass reactor equipped with a sparger for introducing oxygen gas, a stirring turbine blade, and a reflux condenser at the bottom of the reactor. To this, a part of the monomer dissolved in a part of toluene is added (or not), and oxygen is introduced from a sparger. The gas phase is purged with nitrogen for safety. This point is defined as the polymerization start time. Immediately, a solution prepared by dissolving the remaining (or all) monomer in toluene is additionally introduced into the reactor over 30 minutes by a pump. The time when the additional introduction is completed is defined as a calculated value (charge value) based on all the charged mixtures. Sampling a small amount at any time, ED
After adding an aqueous solution of TA3 potassium salt and stirring, an equal volume of methanol is added to precipitate the polymer. The precipitated polymer is filtered, washed three times with methanol, and vacuum dried at 145 ° C. for 1 hour. The ηsp / c of the dried polymer is measured, and the time from the start of polymerization at which a desired ηsp / c is reached is determined from a curve of ηsp / c with respect to the polymerization time. This time is defined as the required time.

Although there is a debate about the desired value of ηsp / c, here, ηsp / c = 0.75 dl / g
And

[0053]

Comparative Example 1 0.4213 g of cuprous oxide and 9.084 of a 48 wt% aqueous hydrogen bromide solution were placed in a reactor described in the general procedure.
g of methanol, and 9.2 g of methanol containing 5.3 wt% of water was added thereto and stirred well. Where N, N'-
1.995 g of di-t-butylethylenediamine, di-n
-Butylamine 6.129 g, butyldimethylamine 1
1.71 g, 0.63 g of trioctylmethylammonium chloride and 1469.7 g of toluene were added. Oxygen was introduced into the reactor, and immediately, a solution of 609.68 g of 2,6-dimethylphenol dissolved in the same weight of toluene was added by a plunger pump over 30 minutes.
The calculated value (based on 1 kg) of the total charged mixture is that the monomer concentration is 20.8 wt% and the amount of copper atoms is 2.0%.
1 mmol, the amount of bromine atoms is 18.4 mmol, and the amount of N, N'-di-tert-butylethylenediamine is 3.95 mmol. According to the calculation, the amount of copper atom = 0.1 per mole of 2,6-dimethylphenol.
18 mol%, amount of bromine atom = 1.08 mol%, N, N '
-Amount of di-t-butylethylenediamine = 0.232 mol%. Sampling was started little by little after the polymerization liquid began to have a slight viscosity, and the required time was determined by measuring ηsp / c. The required time was 160 minutes.

[0054]

Comparative Example 2 0.3037 g of cuprous oxide and 6.548% by weight of a hydrogen bromide aqueous solution 6.548 were placed in a reactor described in the general procedure.
g of methanol, and 9.2 g of methanol containing 5.3 wt% of water was added thereto and stirred well. Where N, N'-
1.438 g of di-t-butylethylenediamine, di-n
4.418 g of butylamine, 8.447 g of butyldimethylamine, 0.63 g of trioctylmethylammonium chloride and 1802.0 g of toluene were added.
Oxygen was introduced into the reactor in the same manner as in Comparative Example 1, and immediately, a solution prepared by dissolving 439.46 g of 2,6-dimethylphenol in the same weight of toluene was mixed with a plunger pump.
Added over a minute. Per kg of the whole mixture (standard)
Is calculated as follows: the monomer concentration is 15.0 wt%, the amount of copper atoms is 1.449 mmol, the amount of bromine atoms is 13.3 mmol, N, N'-di-t-butylethylenediamine Is 2.85 mmol. According to the calculation, for 1 mol of 2,6-dimethylphenol,
Amount of copper atoms = 0.118 mol%, amount of bromine atoms = 1.0
8 mol%, the amount of N, N'-di-t-butylethylenediamine = 0.232 mol%. That is, in this example, the catalyst component is changed in proportion to the monomer. Although not described in detail, in this example, other amounts of the catalyst component are also changed in proportion to the monomer. Sampling was started little by little after the polymerization liquid began to have a slight viscosity, and the required time was determined by measuring ηsp / c. The required time was 16 as in Comparative Example 1.
It was 0 minutes.

Comparing Comparative Example 1 and Comparative Example 2, when the 2,6-dimethylphenol concentration is lower than 23 wt%,
When ηsp / c reaches the desired value of 0.75, it means that the catalyst component can be used in a certain period of time by performing it in molar proportion to 2,6-dimethylphenol.

[0056]

COMPARATIVE EXAMPLE 3 0.4656 g of cuprous oxide and 10.04% of a 48 wt% aqueous hydrogen bromide solution were placed in the reactor described in the general procedure.
g of methanol, and 9.2 g of methanol containing 5.3 wt% of water was added thereto and stirred well. Where N, N'-
2.21 g of di-t-butylethylenediamine, di-n-
6.774 g of butylamine, butyldimethylamine 1
2.95 g, 0.63 g of trioctylmethylammonium chloride and 1344.5 g of toluene were added. Oxygen was introduced into the reactor, and immediately, a solution in which 673.84 g of 2,6-dimethylphenol was dissolved in the same weight of toluene was added over 30 minutes by a plunger pump.
The calculated value per kg of the whole mixture (reference) is 2,
6-dimethylphenol concentration is 23.0 wt%,
The amount of copper atoms is 2.22 mmol, the amount of bromine atoms is 20.3 mmol and the amount of N, N'-di-t-butylethylenediamine is 4.37 mmol. According to the calculation, for 1 mol of 2,6-dimethylphenol,
Amount of copper atoms = 0.118 mol%, amount of bromine atoms = 1.0
8 mol%, the amount of N, N'-di-t-butylethylenediamine = 0.232 mol%. That is, the catalyst component was used in proportion to the number of moles of 2,6-dimethylphenol as in Comparative Examples 1 and 2. After the polymerization liquid began to take on a slightly viscous property, sampling was started little by little, and ηsp /
I tried to find the required time by measuring c,
When ηsp / c exceeds 0.5 dl / g, ηsp / c
It was recognized that a small amount of an insoluble component insoluble in chloroform was generated in a part of the polymer sampled for the measurement of c, and that the amount increased with the polymerization time.

[0057]

Comparative Example 4 0.6074 g of cuprous oxide and 13.10 aqueous solution of 48 wt% hydrogen bromide were added to the reactor described in the general procedure.
g of methanol, and 9.2 g of methanol containing 5.3 wt% of water was added thereto and stirred well. Where N, N'-
2.877 g of di-t-butylethylenediamine, di-n
8.835 g of butylamine, 1 butyldimethylamine
6.89 g, 0.63 g of trioctylmethylammonium chloride and 944.24 g of toluene were added. Oxygen was introduced into the reactor, and immediately, a solution prepared by dissolving 878.93 g of 2,6-dimethylphenol in the same weight of toluene was added by a plunger pump over 30 minutes.
The calculated value per kg of the whole mixture (reference) is 2,
The 6-dimethylphenol concentration is 30.0 wt%,
The amount of copper atoms is 2.898 mmol, the amount of bromine atoms is 26.5 mmol and the amount of N, N'-di-t-butylethylenediamine is 5.70 mmol. According to the calculation, the amount of copper atoms = 0.118 mol% and the amount of bromine atoms = 1 mol of 2,6-dimethylphenol =
1.08 mol%, the amount of N, N'-di-t-butylethylenediamine = 0.232 mol%. That is, the catalyst component was used in proportion to the number of moles of 2,6-dimethylphenol as in Comparative Examples 1, 2 and 3. Sampling was started in small increments after the polymerization liquid began to have a slight viscosity, and the required time was determined by measuring ηsp / c. However, when ηsp / c exceeded 0.5 dl / g, It was found that some of the polymer sampled for c measurement had insolubles insoluble in chloroform, and this amount increased with the polymerization time. This generation amount was larger than that of Comparative Example 3.

As is clear from comparison between Comparative Examples 1, 2, 3, and 4, the monomer concentration was 23 wt.
%, The effect of reaching the desired ηsp / c in the required time can be obtained if the catalyst components are performed in proportion to the monomer. However, when the monomer concentration is 23 wt% or more, the catalyst components are converted to the number of moles of the monomer. In the case of performing in proportion, it can be understood that an insoluble matter is generated due to some side reaction, and that the polyphenylene ether polymer is altered in some way.

[0059]

Example 1 In a reactor described in the general procedure, 0.3556 g of cuprous oxide and 1.361 of a 47 wt% aqueous solution of hydrogen bromide were added.
15.6 g of N, N'-di-t-butylethylenediamine 0.8566 g, di-n-butylamine 4.1469 g, butyldimethylamine 10.518
g, trioctylmethyl ammonium chloride 0.2
4 g and 641.345 g of toluene were added. Further, 27.6 g of 2,6-dimethylphenol was added to 26.5 g.
A solution dissolved in 18 g of toluene was added. Oxygen was introduced into the reactor, and immediately, a plunger pump was used for 24 hours.
8.4 g of 2,6-dimethylphenol was added to 238.66.
g of toluene was added over 30 minutes. The calculated value (reference) per kg of the whole charged mixture is 2,6.
-The concentration of dimethylphenol is 23.0 wt%, the amount of copper atoms is 4.14 mmol, the amount of bromine atoms is 6.59 mmol, and the amount of N, N'-di-t-butylethylenediamine is 4.14 mmol. According to the calculation, the amount of copper atoms per mole of monomer = 0.2
2 mol%, amount of bromine atom = 0.35 mol%, N, N'-
Amount of di-t-butylethylenediamine = 0.22 mol%
It is. Sampling was started little by little after the polymerization liquid began to have a slight viscosity, and the required time was determined by measuring ηsp / c. The generation of insoluble components observed in the comparative example was not observed. The required time was 115 minutes.

[0060]

Example 2 In a reactor described in the general procedure, 0.3556 g of cuprous oxide and 1.361 of a 47 wt% aqueous solution of hydrogen bromide were added.
1 g of the mixture was added and mixed, and N, N'-di-t-butylethylenediamine 0.8566 g, di-n-butylamine 4.6879 g, butyldimethylamine 11.89
g, trioctylmethyl ammonium chloride 0.2
4 g and 568.845 g of toluene were added. Further, 31.20 g of 2,6-dimethylphenol was added to 29.
A solution dissolved in 977 g of toluene was added. Oxygen was introduced into the reactor and the plunger pump was immediately used for 28
0.8 g of 2,6-dimethylphenol was added to 269.78.
g of toluene was added over 30 minutes. The calculated value (reference) per kg of the whole charged mixture is 2,6.
-The concentration of dimethylphenol is 26.0 wt%, the amount of copper atoms is 4.14 mmol, the amount of bromine atoms is 6.59 mmol, and the amount of N, N'-di-t-butylethylenediamine is 4.14 mmol. That is,
Only the 2,6-dimethylphenol concentration was increased for all the charged mixtures, and the catalyst concentration was constant for all the charged mixtures as in Example 1. After the polymerization liquid starts to take on a slight viscosity, start sampling little by little,
The required time was determined by measuring ηsp / c. The generation of insoluble components observed in the comparative example was not observed. The required time was 112 minutes.

[0061]

Example 3 In a reactor described in the general procedure, 0.3556 g of cuprous oxide and 1.361 of a 47 wt% aqueous hydrogen bromide solution were added.
1 g of the mixture, and N, N'-di-t-butylethylenediamine 0.8566 g, di-n-butylamine 5.409 g, butyldimethylamine 13.72 g,
Trioctylmethylammonium chloride 0.24g
And 472.176 g of toluene. 3 more
34.58 of 6.00 g of 2,6-dimethylphenol
A solution dissolved in 8 g of toluene was added. Oxygen was introduced into the reactor and immediately with a plunger pump, 324.
31.294 g of 0 g of 2,6-dimethylphenol
Was added over 30 minutes. The calculated value per kg of the whole mixture (base) is 2,6-
The dimethylphenol concentration was 30.0 wt%, the amount of copper atoms was 4.14 mmol, and the amount of bromine atoms was 6.
59 mmol and the amount of N, N'-di-t-butylethylenediamine is 4.14 mmol. That is, only the 2,6-dimethylphenol concentration was increased with respect to the entire charged mixture, and the catalyst concentration was constant with respect to the entire charged mixture as in Example 1. After the polymerization liquid began to take on a slightly viscous property, sampling was started little by little, and ηs
The required time was determined by measuring p / c. The generation of insoluble components observed in the comparative example was not observed. The required time was 110 minutes.

As seen in the examples, the monomer concentration was 23
wt% or more and the specific component of the catalyst at a certain amount or less, a desired reaction can be performed in a short time in a desired ηsp.
/ C can be increased.

[0063]

According to the present invention, a method for efficiently producing polyphenylene ether at a high concentration can be provided. The fact that it is possible to increase the desired reaction at a high concentration to a desired ηsp / c in a short time can be said to have an effect of inducing an improvement in productivity and producing a low-cost polyphenylene ether.

Claims (4)

[Claims] 1. A method for producing a polyphenylene ether by oxidatively polymerizing a phenolic compound in the presence of a copper-amine catalyst, wherein the concentration of the phenolic compound on the basis of the whole charged mixture is 23% by weight or more, and a part of the catalyst is used. It contains a copper compound and a bromine compound as specific components, and the amount of the copper compound as the specific component in terms of copper atoms does not exceed 5 mmol per 1 kg of the whole mixture. Wherein the amount is less than or equal to a specific amount in a range not exceeding 20 mmol. 2. The catalyst comprises (a) a copper compound, (b) a bromine compound, and (c) a compound represented by the following formula (1). (In the formula, R ₁ , R ₂ , R ₃ , and R ₄ are each independently hydrogen, a linear or branched alkyl group having 1 to 6 carbon atoms, and not all hydrogen atoms at the same time. R ₅ has 2 carbon atoms. To a linear or methyl-branched alkylene group of (a) to (c), (d) a tertiary monoamine, and (e) a secondary monoamine. The amount of copper atoms of the catalyst component (a) per kg is 5
2. The process according to claim 1, wherein the amount of bromine atoms in the catalyst component (b) per 1 kg of the whole mixture does not exceed 20 mmol within a range not exceeding mmol. 3. The process according to claim 2, wherein the amount of the diamine molecule of the catalyst component (c) per 1 kg of the whole charged mixture does not exceed 10 mmol. 4. The method according to claim 1, wherein the total charged mixture contains not more than 0.1% by weight of a tetraalkylammonium salt compound, a polyethylene glycol group-containing alkylamine or a polyethylene glycol group-containing alkylammonium salt compound. A method for producing polyphenylene ether.