JPH05140297A - Production of polyaryl ether - Google Patents

Abstract

PURPOSE:To obtain a polyaryl ether having an improved resistance to coloration. CONSTITUTION:A dihalogenodiphenyl compd. and a dihydric phenol compd. are stirred under heating in an org. polar solvent in the presence of an alkali metal compd. thermally pretreated in an inert gas, thus giving the objective polyaryl ether having an improved resistance to coloration and excellent heat resistance and mechanical strengths.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention has an improved coloring degree,
The present invention relates to a method for producing a polyaryl ether having excellent heat resistance and mechanical strength.

[0002]

2. Description of the Related Art Polyaryl ether is a polycondensation reaction between a dihydric phenol compound and a dihalogenodiphenyl compound in an organic polar solvent in the presence of an alkali metal compound, or an alkali metal dihydric phenol compound. It is known that a salt is previously synthesized and obtained by a polycondensation reaction with a dihalogenodiphenyl compound (Japanese Patent Publication Nos. 42-7799 and 45-2131).
No. 8, JP-A-48-19700). In the polycondensation reaction, when the reaction temperature is high, there is a problem that the obtained polymer is colored brown due to deterioration of the solvent or oxidation of the polymer raw material. In order to solve the above problems, a method using an alkyl-substituted amide, urea or the like as a solvent (Japanese Patent Publication No. 46-18146), a method of distilling off the solvent after polycondensation reaction in an organic amide solvent (special method Kaisho 5
9-74123) has been proposed. However, these methods have drawbacks such as insufficient coloration prevention and a complicated manufacturing process.

[0003]

SUMMARY OF THE INVENTION The present invention provides a process for producing polyaryl ethers with improved color.

[0004]

The present invention is directed to heating and stirring a dihalogenodiphenyl compound and a dihydric phenol compound in an organic polar solvent in the presence of an alkali metal compound heat-treated in an inert gas. And a method for producing a polyaryl ether.

Examples of the alkali metal compound in the present invention include alkali metal carbonates, alkali metal hydroxides, alkali metal hydrides and alkali metal alkoxides. Particularly, sodium carbonate and potassium carbonate are preferably used. As a heat treatment method for the alkali metal compound, heating is carried out in an inert gas such as nitrogen gas or argon, preferably in a temperature range of 60 to 500 ° C. If the heating temperature is too low, the effect of improving the coloring degree of the obtained polyaryl ether is small, and if the heating temperature is too high, the decomposition reaction of the alkali metal salt may occur, which is not preferable. The heat treatment time is preferably 1 minute or more. The heat treatment may be performed under normal pressure or reduced pressure.

The dihalogenodiphenyl compound has the general formula

[0007]

[Chemical 1] (In the formula, X and X ′ are the same or different halogen atoms.). Examples of preferable dihalogenodiphenyl compounds include 4,4′-dichlorodiphenyl sulfone and 4,4′-difluorodiphenyl ketone.

As the dihydric phenol compound, at least one of hydroquinone, catechol, resorcin, 4,4'-biphenol, bis (hydroxyphenyl) alkanes, dihydroxydiphenylsulfones, dihydroxydiphenylethers, or their benzene ring hydrogen is used. An appropriate substituent (eg, a lower alkyl group such as a methyl group, an ethyl group or a propyl group, or a substituent such as an alkoxy group such as a methoxy group or an ethoxy group)
Those substituted with can be mentioned. Alternatively, two or more kinds of the above dihydric phenol compounds may be mixed and used. The dihydric phenol compound is preferably used in a substantially equimolar amount with the dihalogenodiphenyl compound. In order to control the molecular weight of the polyaryl ether to be produced, it may be used in an equimolar amount to a slight excess amount or a slight excess amount. For this purpose, small amounts of monohalogenodiphenyl compounds or monohydric phenol compounds can be added to the polymerization solution.

Examples of the organic polar solvent include sulfoxide solvents such as dimethyl sulfoxide and diethyl sulfoxide, amide solvents such as N, N-dimethylformamide and N, N-dimethylacetamide, and N-methyl-solvent.
Pyrrolidone-based solvents such as 2-pyrrolidone and N-vinyl-2-pyrrolidone, piperidone-based solvents such as N-methyl-2-piperidone, 1,3-dimethyl-2-imidazolinone, 1,3-diethyl-2-imidazo 2- such as Linon
Imidazolinone-based solvent, hexamethylene sulfoxide,
γ-butyrolactone, sulfolane and the like can be mentioned.

In the present invention, the polycondensation reaction of a dihydric phenol compound and a dihalogenodiphenyl compound is carried out in the presence of an alkali metal carbonate heat-treated in an inert gas in the above organic polar solvent at a polymerization temperature of 140 to 270. Perform at ℃.
Water produced as a by-product during the reaction can be distilled out of the system with an inert gas stream or with an azeotropic dehydrating agent to produce a high molecular weight polyaryl ether. As an azeotropic dehydrating agent, benzene, toluene, xylene, an aromatic halogen compound or the like is used. At the end of the polycondensation, chloromethane, for example, 90-
You may add by blowing in at 150 degreeC. In the above production method, a polymer having a desired molecular weight is obtained as a reaction solution of an organic polar solvent.

The inorganic solid such as alkali metal carbonate or alkali metal halide remaining in the reaction solution can be separated by filtering or centrifuging the reaction solution. After separating the inorganic solid contained in the reaction solution by filtration or centrifugation, or without separating the inorganic solid, a poor solvent can be added to the reaction solution to separate the polyaryl ether as a precipitated solid. .. Examples of the poor solvent for the polyaryl ether include alcohols such as methanol, ethanol, isopropanol, butanol, nitriles such as acetonitrile, water and the like. Further, two or more kinds of the above compounds can be mixed and used. Further, the poor solvent may contain a good solvent for the polymer such as the above-mentioned polymerization reaction solvent in the range in which the polymer can be precipitated.

The precipitated solid is washed with a poor solvent and then dried to obtain a polyaryl ether powder. Molded parts of this polymer have excellent mechanical properties.

[0013]

Industrial Applicability According to the method of the present invention, it is possible to produce a polyaryl ether having less polymer coloration and excellent heat resistance and mechanical strength.

[0013]

EXAMPLES Examples of the present invention will be described below. The degree of coloring in the examples was evaluated by the degree of yellowness (YI value) measured according to JIS K7103.

Example 1 4,5 g of 4,4'-dichlorodiphenyl sulfone, 234 g of hydroquinone, 170 of 4,4'-bisphenol
g, 0.1 L of azeotropic dehydration toluene, and 7 in nitrogen gas
470 g of potassium carbonate heat-treated at 0 ° C. for 30 minutes,
After adding to 3.2 L of N-methyl-2-pyrrolidone, the mixture was stirred under a nitrogen atmosphere at about 180 ° C. for 8 hours to obtain a polymerization solution. After completion of the reaction, the inorganic solution was filtered at a nitrogen pressure of 1.5 kg / cm ² to separate it from the polymerization solution, and the polymerization solution (polymer concentration about 24% by weight, solution viscosity 5700 cp (30 ° C.))
Got 1 kg of 80 ° C polymerization solution in 6 kg of 80 ° C water
Was poured and the mixture was stirred at 5000 rpm to precipitate a polymer, which was then filtered and separated by a centrifuge to obtain a polymer. After washing 0.1 kg of this polymer with 1 L of water at 80 ° C, 90 ° C
It was dried in a vacuum to obtain a powder of polyaryl ether sulfone. The obtained polyether sulfone powder was melt-molded at 340 ° C. to form a plate having a thickness of 0.3 mm, and the yellowness (Y
I) was measured. The YI value was 6.8.

Example 2 879 g of 4,4'-dichlorodiphenyl sulfone, 165 g of hydroquinone, 279 g of 4,4 'biphenol,
0.1 L of azeotropic dehydration toluene and 200 in nitrogen gas
470 g of potassium carbonate heat-treated for 10 minutes at
After adding to 3.2 L of -methyl-2-pyrrolidone, the mixture was stirred under a nitrogen atmosphere at about 180 ° C for 8 hours to obtain a polymerization solution.
After completion of the reaction, the inorganic material was filtered at a nitrogen pressure of 1.5 kg / cm ² to separate it from the polymerization solution, to obtain a polymerization solution (polymer concentration: about 25% by weight, solution viscosity: 5000 cp (30 ° C.)). The polymer was precipitated, washed, dried and melt-molded in the same manner as in Example 1 to form a plate having a thickness of 0.3 mm, and the yellowness index (YI) was measured. The YI value was 6.2.

Example 3 879 g of 4,4'-dichlorodiphenylsulfone, 165 g of hydroquinone, 279 of 4,4'-biphenol
g, 0.1 L of azeotropic dehydration toluene, and 1 in nitrogen gas
470 g of potassium carbonate heat-treated at 00 ° C for 30 minutes
Was added to 3.2 L of N-methyl-2-pyrrolidone,
The mixture was stirred under a nitrogen atmosphere at about 180 ° C. for 9 hours to obtain a polymerization solution. After completion of the reaction, the inorganic solution was filtered under a nitrogen pressure of 1.5 kg / cm ² to separate it from the polymerization solution, and the polymerization solution (polymer concentration: about 27% by weight;
C)) was obtained. Precipitating the polymer in the same manner as in Example 1,
The plate was washed, dried and melt-molded to form a plate having a thickness of 0.3 mm, and the yellowness index (YI) was measured. The YI value was 2.3.

Comparative Example 1 A polymerization reaction was carried out in the same manner as in Example 1 except that potassium carbonate was used without heat treatment. After completion of the reaction, nitrogen pressure of 1.5 kg / in order to separate the inorganic substance from the polymerization solution.
was filtered through cm ^2, the polymerization solution (polymer concentration about 24 weight percent,
A solution viscosity of 5600 cp (30 ° C.) was obtained. The polymer was precipitated, washed, dried and melt-molded in the same manner as in Example 1 to form a plate having a thickness of 0.3 mm, and the yellowness index (YI) was measured. The YI value was 13.2.

Comparative Example 2 A polymerization reaction was carried out in the same manner as in Example 2 except that potassium carbonate was used without heat treatment. After completion of the reaction, nitrogen pressure of 1.5 kg / in order to separate the inorganic substance from the polymerization solution.
was filtered through cm ^2, the polymerization solution (polymer concentration about 24 weight percent,
A solution viscosity of 5600 cp (30 ° C.) was obtained. After completion of the reaction, nitrogen pressure is 1.5 to separate the inorganic matter from the polymerization solution.
It was filtered at kg / cm ² to obtain a polymerization solution (polymer concentration: about 24% by weight, solution viscosity: 5600 cp (30 ° C.)). The polymer was precipitated, washed, dried and melt-molded in the same manner as in Example 1 to prepare a plate having a thickness of 0.3 mm, and the yellowness index (YI).
Was measured. The YI value was 9.4. Comparative Example 3 The polymerization reaction was performed in the same manner as in Example 3 except that potassium carbonate was used without heat treatment. After completion of the reaction, nitrogen pressure of 1.5 kg / in order to separate the inorganic substance from the polymerization solution.
was filtered through cm ^2, the polymerization solution (polymer concentration about 24 weight percent,
A solution viscosity of 5100 cp (30 ° C.) was obtained. The polymer was precipitated, washed, dried and melt-molded in the same manner as in Example 1 to form a plate having a thickness of 0.3 mm, and the yellowness index (YI) was measured. The YI value was 15.2.

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Hiroyuki Fukuda 8-1 Goi Minamikaigan, Ichihara City, Chiba Ube Industries Ltd. Chiba Research Institute

Claims (1)

[Claims] 1. A method for producing a polyaryl ether, which comprises heating and stirring a dihalogenodiphenyl compound and a dihydric phenol compound in an organic polar solvent in the presence of an alkali metal compound heat-treated in an inert gas. Method.