JPS62184023A - Production of 2,6-disubstituted phenolic polymer - Google Patents

Abstract

PURPOSE:To produce the titled polymer of any desired MW within a short time in good yields, by oxidatively coupling a 2,6-disubstituted phenol with an oxygen-containing gas in the presence of a specified highly active catalyst. CONSTITUTION:A highly active polymerization catalyst is obtained by adding a basic compound selected from among primary and/or secondary amines (e.g., methylamine) and hydroxides, alkoxides and phenoxides of metals of Group Ia of the periodic table (e.g., NaOH) to a Mn salt (e.g., MnO2), reacting the mixture in a medium (e.g., methanol) at -20-100 deg.C while blowing at least 0.15mol, per mol of Mn, of an oxygen-containing gas of an oxygen content of 5-100vol% into the mixture. A 2,6-disubstituted phenol of the formula (wherein R1 is a 1-4C hydrocarbon, R2 is a halogen or R1) is oxidatively coupled with an oxygen-containing gas to obtain polyphenylene ether of an etasp/C>=0.45.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention provides a method for producing a 2,6-disubstituted phenol polymer,
More specifically, 2.6-
In oxidative polymerization of di-substituted phenol, by supplying an oxygen-containing gas during catalyst synthesis and producing it while contacting it, polymerizability can be dramatically increased and polyphenylene ether with the desired molecular weight can be obtained in a short time. The present invention relates to a method for producing a 2,6-disubstituted phenol polymer, which is characterized in that the polymerization is carried out in the presence of a highly activated catalyst.

(Prior art) Conventionally, oxidized polymers of 2,6-disubstituted phenols have been known as polyphenylene ethers, which have excellent mechanical properties, electrical properties, heat resistance, etc., and have low water absorption. In recent years, it has attracted attention as a thermoplastic engineering plastic due to its properties such as good dimensional stability.

As polymerization catalysts for 2.6--/substituted phenols, a large number of catalyst systems have been proposed so far, such as copper-based catalysts, manganese-based catalysts, and conolt-based catalysts. Examples of manganese-based catalysts include those disclosed in Japanese Patent Publication No. 45-30355, Japanese Patent Application Laid-Open No. 79993-1983, and Japanese Patent Application Laid-Open No. 57-44625.

(Problems to be Solved by the Invention) 2. In Japanese Patent Publication No. 45-30355, basic compounds,
A catalyst consisting of a combination of a manganese compound and one selected from primary, primary, and tertiary amines has been proposed; A polymerization catalyst system that combines 2.
The polymerizability of 6-disubstituted phenol is still insufficient, and in order to obtain polyphenylene ether with the desired molecular weight, the reaction must be carried out for a long time or the amount of catalyst must be increased, which is not desirable from an industrial perspective. It has its drawbacks.

Further, in these inventions, when synthesizing a polymerization catalyst, only the order of addition is described, but the conditions for synthesizing the catalyst are not described at all.

(Means for Solving the Problem) As a result of extensive research aimed at improving the polymerizability of 2,6-disubstituted phenols, the present inventors discovered that 2,6-disubstituted phenols We have discovered that by supplying an oxygen-containing gas without the presence of phenol, the polymerizability of 2,6-disubstituted phenol can be dramatically increased, and polyphenylene ether of the desired molecular weight can be obtained in a short time. The present invention has now been completed.

The effect of actively supplying and contacting an oxygen-containing gas during catalyst synthesis in the present invention is that the manganese ions in the manganese salt are oxidized by the supplied oxygen, and at the same time This is thought to be due to the coordination of K, which forms a complex compound and dissolves, and all the manganese ions contribute to the polymerization reaction.

The 2,6-disubstituted phenol used in the method of the present invention has the following general formula (I) (where RI is a hydrocarbon group having 1 to 4 carbon atoms, and R2 is a halogen or a hydrocarbon group having 1 to 4 carbon atoms. 2.6-dimethylphenol, 2-methyl-6-ethylphenol, 2.6-dinitylphenol, 2-ethyl-6- h-propylphenol, 2-methyl-6-chlorophenol, 2-meth-fk-6-promophenol, 2-methyl-6-ituprobylphenol,
2-Methyl-6-n-propylphenol, 2-ethyl-6-bromophenol, 2-methyl-6-n-1 thylphenol, 2.6-)-n-furobylphenol, 2-ethyl-6- Examples include chlorphenol. These compounds may be used alone or in combination of two or more. In addition, small amounts of orthocresol, metacresol, Nomura Reso-A/, 2.4--
) Even if it contains methylphenol, 2-ethylferer, etc., there is no practical problem.

Among these 2.6-disubstituted phenols, especially 2.6-disubstituted phenols
-Dimethylphenol is important.

Manganese salts used in the method of the present invention include, for example, manganese halides such as manganese chloride, manganese bromide, and manganese iodide; manganese salts of inorganic acids such as manganese nitrate, manganese sulfate, and manganese carbonate; manganese formate, manganese acetate, and Manganese salts of organic acids such as manganese acid, manganese stearate, manganese octylate, manganese benzoate, etc. Manganese (such as manganese)
l) Salts; Manganates such as sodium manganate and potassium manganate; Permanganates such as sodium permanganate and potassium permanganate; Manganese hydroxide i
Manganese dioxide is mentioned.

The preferred amount of these manganese salts to be used is from 0.1 to 5 mol, more preferably from 0.5 to 3 mol, based on the 2,6-disubstituted phenol.

Examples of the basic compound used in the method of the present invention include hydroxide-rich sodium methoxide, potassium methoxide, sodium ethoxide, etc. in the Group IA metal region of the periodic table, such as lithium hydroxide, sodium hydroxide, and potassium hydroxide; Alkoxides such as sodium-n-propoxide, sodium impropoxide, potassium-t-butoxide;
Examples include phenoxides such as lithium phenoxide, sodium phenoxide, and potassium phenoxide.

1. Of course, it is acceptable even if the phenol constituting the phenoxide is substituted with a halogen or a hydrocarbon group having 1 to 4 carbon atoms.

Preferred among these basic compounds are sodium hydroxide or potassium hydroxide.

The amount of the basic compound used in the method of the present invention is preferably 1 to 20 mol, more preferably 2 to 10 mol, based on the 2.6-, 1-substituted phenol.

The primary amines used in the method of the present invention include aliphatic amines such as methylamine, propylamine, and butylamine; cyclic hydrocarbon-substituted amines such as cyclohexylamine; ethylenediamine, triethylenediamine, Diamines such as hexamethylenediamine; aliphatic secondary amines such as dimethylamine, diethylamine, dipropylamine, dibutylamine; Examples include alicyclic secondary amines such as.

The preferred amount of amine added in the method of the present invention is 2.6-
-,' is 0.5 mole or more relative to the substituted phenol,
The upper limit is preferably up to 10 mol.

The oxygen-containing gas supplied during catalyst synthesis used in the method of the present invention has an oxygen content of 5 to 100 volumes, and other gases other than oxygen include nitrogen, carbon dioxide, helium, albin, neon, etc. It is an inert gas. Inert gases can be used alone or in combination of two or more. A preferred inert gas is nitrogen;
The oxygen-containing gas at this time is produced by mixing oxygen and nitrogen or by mixing air and 9 elements. Specifically, oxygen (
It is preferable to use air (oxygen concentration: 21 volumes fI'), or a mixed gas of oxygen and nitrogen containing 5 volumes or more of oxygen.

The amount of oxygen-containing gas supplied during catalyst synthesis used in the method of the present invention is such that the amount of oxygen contained in the oxygen-containing gas is 0.15 molti or more, preferably 0. .3 to 20 molti.

The method of supplying an oxygen-containing gas in the present invention is to supply an oxygen-containing gas and bring it into contact when synthesizing a polymerization catalyst consisting of a basic compound, a manganese salt, and a primary and/or primary amine. However, the present invention cannot be achieved by a method in which an oxygen-containing gas is supplied and contacted after each catalyst component is mixed.

In synthesizing the catalyst by the method of the present invention, the order in which the three catalyst components, ie, a basic compound, a manganese salt, and a primary and/or primary amine, are mixed is 2,6-disubstituted phenol. The sequence of adding primary and/or primary thymine to the manganese salt, followed by the addition of the basic compound, or adding the primary and/or primary thymine to the manganese salt without the presence of thymine and the basic compound. The order is that the compounds are added simultaneously.

The catalyst synthesis reaction in the method of the present invention is carried out at -20 to 100°C.
, preferably at a temperature of 0 to 50° C., by supplying an oxygen-containing gas under normal or elevated pressure.

The medium used during the catalyst synthesis in the uninvented method is preferably one that dissolves the manganese salt and the basic compound. These include methanol, ethanol, impropanol, n-pronol, n-butanol,
Examples include alcohols such as benzyl alcohol and cyclohexanol.

The polymerization medium used in the method of the present invention is particularly suitable as long as it is less likely to be oxidized than the phenols to be oxidized and has no reactivity with various radicals that are thought to be generated during the reaction process. Although there are no limitations, it is preferable to use one that can dissolve a phenol derivative and a catalyst consisting of manganese ions. For example, such things include:
Aromatic hydrocarbons such as benzene, toluene, ethylbenzene, and xylene; chloroform, 1,2-dichloroethane, trichloroethane, chlorobenzene, and dichlorobenzene; nitro compounds such as nitrobenzene; Alcohols such as methanol, ethanol, propatool, benzyl alcohol, and cyclohexanol; ketones such as acetone and methyl ethyl ketone; esters such as ethyl acetate and formate; ethers such as tetrahydrofuran and diethyl ether; Can be used as a good solvent for catalysts. Therefore, it is preferable to configure the solvent by using a polymer solvent alone or a combination of two or more kinds of the polymer solvent and a good solvent for the catalyst. Depending on the combination ratio of this polymer good solvent and catalyst good solvent, the polymerization method can be a solution polymerization method,
It is also a precipitation polymerization method in which the polymer precipitates in the late stage of polymerization. In the method of the present invention, a precipitation polymerization method in which the polymer is precipitated in the late stage of polymerization is preferred.

(Effects of the Invention) According to the method of the present invention, industrially useful high molecular weight can be achieved by a short reaction time when the same amount of catalyst is used, and with a small amount of catalyst when the polymerization reaction time is the same. of polyphenylene ether is obtained. (The industrially useful high molecular weight polyphenylene ether referred to in the present invention is ηs
The polymer has a p/C of at least 0.45, preferably 0.50 or more. ) (Examples) Hereinafter, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to these Examples in any way.

Note that the polymerization activity is ηsp/4 hours after the start of polymerization.
The determination was made by measuring C. ηsp/C is 0.
The 5-dichloroform solution was measured using a Cannon-Fenske viscosity tube at a temperature of 30°C.

Example 1 Manganese chloride (tetrahydrate) 1.5 g (0,0075 mol)
was dissolved in 150 g of methanol and equipped with a thermometer, reflux condenser, oxygen gas introduction nozzle, and stirrer. The mixture was placed in a jacketed reactor, and the internal temperature was controlled at 30°C without stirring. Then, add 100Nd of oxygen.
di-n-butylamine x while blowing at a rate of /min.
, 9g (o, 015 mol) were added. Next, 1.6 g (0.04 mol) of sodium hydroxide was added to 50 g of methanol.
The VC solution was added to the reactor.

20 minutes after starting the addition of di-n-butylamine and ending the addition of the methanol solution of sodium hydroxide.
I did it in minutes. This completes the synthesis of the catalyst.

12.2 g (1.0 mol) of 2.6-sitathylphenol was mixed with 600 g of xylene and 200 g of n-sitanol.
and added to the reactor. Oxygen supply amount is 500we
At 7 minutes, the polymerization reaction was started. The jacket temperature was controlled to maintain the reaction temperature at 30°C. About 30 minutes after the start of the reaction, polymer particles were precipitated.

4 hours after the start of the reaction, the blowing of oxygen was stopped to terminate the reaction.

After the reaction, the precipitated polymer was separated and washed with a mixed solution of methanol and hydrochloric acid, and then washed with methanol.
) did. It was dried at 145° C. for 30 minutes to obtain a polyphenylene ether powder. The yield is 96 cm, ηsp/
C was 0.74.

Comparative Example 1 Catalyst synthesis was carried out in the open atmosphere without blowing in an oxygen-containing gas, and when Example 1 was repeated, a polymer with ηsp/C0.38 was obtained in a yield of 85 cm.

Ratio 1 and f 2 Except for the following, the same method as in Example 1 was used, except for the catalyst amount fik.
And a polymerization reaction was carried out to obtain polyphenylene 1-thyl. To synthesize the polymerization catalyst, use 100 g of the methanol used to dissolve manganese chloride (tetrahydrate) to dissolve 24.4 g of 2,6-situtylphenol, and dissolve manganese chloride (tetrahydrate). salt) was added to the methanol solution. Moreover, 2,6-sitalyphenol used in the polymerization reaction was 97.6 g.

As a result, the obtained polyphenylene ether ηsp/
C was 0.37, and the yield was 83 cm.

Comparative Example 3 Catalyst synthesis and polymerization reactions were carried out in the same manner and under the same conditions as in Example 1, except that each catalyst component was charged into a 21-capacity jacketed reactor, stirred and mixed for 5 minutes, and then oxygen was blown into the reactor. carried out.

As a result, ηsp/ of the obtained Irifenylene ether
C was 0.40, and the yield was 85 cm.

Table 1 shows the results obtained in Example 1 and Comparative Examples 1, 2.3.

Table 1 Examples 2 to 10 The same molar amounts of di-n-butylamine or sodium hydroxide were used in place of the primary amines, primary amines, or basic compounds shown in Table 2, and during catalyst synthesis. The same evaluation as in Example 1 was performed except that the same volume of oxygen-containing gas shown in Table 2 was used instead of the oxygen blown into the sample, and the results shown in Table 2 were obtained.

(Left space below) Table 2 Examples 11 to 13 Example 1 except that the same molar amount of di-n-butylamine was used in place of the combination of primary and primary amines in Table 3.
Evaluations were conducted in exactly the same manner as above, and the results shown in Table 3 were obtained.

Table 3 Examples 14 to 19 Evaluations were carried out in exactly the same manner as in Example 2, except that the oxygen injected during catalyst synthesis and the amount of oxygen supplied were replaced with the oxygen-containing gas and amount of supply shown in Table 4. We obtained the results shown below.

(Margin below) Table 4

Claims (6)

[Claims] (1) In a method for producing polyphenylene ether by oxidative coupling of 2,6-disubstituted phenol with an oxygen-containing gas, (A) a hydroxide of a group I A metal of the periodic table;
When synthesizing a polymerization catalyst consisting of a basic compound selected from alkoxides or phenoxides, (B) a manganese salt, and (C) a primary and/or primary amine, oxygen-containing gas is actively used. A method for producing a 2,6-disubstituted phenol polymer, which comprises polymerizing in the presence of a highly activated catalyst obtained by supplying and contacting the polymer. (2) The oxygen-containing gas supplied during catalyst synthesis contains 5
The method according to claim 1, which is a mixed gas of oxygen and nitrogen containing at least % by volume. (3) The method according to claim 1, wherein the oxygen-containing gas supplied during catalyst synthesis is air. (4) The method according to claim 1, wherein the oxygen-containing gas supplied during catalyst synthesis is oxygen. (5) Claims 1, 2, and 3, wherein the 2,6-disubstituted phenol is 2,6-dimethylphenol.
The method described in any of paragraphs and paragraphs 4. (6) The method according to any one of claims 1, 2, 3, 4, and 5, wherein the basic compound is sodium hydroxide or potassium hydroxide.