JPH05301955A - Production of polyaryl ether - Google Patents

Abstract

PURPOSE:To obtain the subject polymer, excellent in heat resistance and mechanical strength and colorless or reduced in coloring by polycondensing a dihalogenodiphenyl sulfone compound with specific dihydric phenoli compounds according to a specific method. CONSTITUTION:(A) A dihalogenodiphenyl sulfone compound (preferably 4,4'- dichlorodiphenyl sulfone, etc.) and (B) dihydric phenol compounds in which >=1wt.% of the total dihydric phenols is a compound of the formula (n is 1 or 2) (e.g. 4,4'-biphenol) are dissolved in an organic polar solvent (preferably N-methyl-2-pyrrolidone, etc.) and the dissolved oxygen concentration in the resultant organic polar solution is then regulated to <=4ppm. The polycondensation of the components (A) with (B) is subsequently carried out in the presence of an alkali metallic compound (preferably sodium carbonate, etc.) in an inert gas atmosphere. Furthermore, an inert gas, e.g. N2 gas is passed through the organic polar solution so as to regulate the dissolved oxygen concentration to <=4ppm.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a polyaryl ether having excellent heat resistance, mechanical strength, and no or reduced coloring.

[0002]

2. Description of the Related Art Polyaryl ethers are
In an organic polar solvent, in the presence of an alkali metal compound, a polycondensation reaction of a dihalogenodiphenyl compound and a dihydric phenol compound, or an alkali metal di-salt of a dihydric phenol is previously synthesized, and a dihalogenodiphenyl compound It is known that it can be obtained by the polycondensation reaction of (JP-B-42-7799, JP-B-45-21318, and JP-A-48-19700). In the polycondensation reaction,
If the reaction temperature is high, deterioration of the solvent or polymer raw materials,
There is a problem that the resulting polymer is colored brown due to oxidation and the like. In order to solve the above problems, a method using an alkyl-substituted amide or urea as a solvent (Japanese Patent Publication No. 46-
18146), after polycondensation reaction in an organic amide solvent,
A method for removing this solvent by distillation (Japanese Patent Laid-Open No. 59-74123).
No.) and a method using an inert organic highly polar amide as a reaction solvent (JP-A-1-245018). Further, generally, only a method of introducing an inert gas such as nitrogen gas into the reaction system is adopted.

[0003]

The present inventors have found that the presence of oxygen in the reaction atmosphere at the time when the dihydric phenol and the alkali metal salt react causes the coloring of the polyaryl ether produced. The organic polar solution in which the divalent phenol compound and the dihalogenodiphenylsulfone compound are dissolved in an organic polar solvent (a solution in which the divalent phenol compound and the dihalogenodiphenylsulfone compound are all dissolved in the organic polar solvent, and It includes both partially dissolved solutions) and the dissolved oxygen concentration is 4
It was clarified that the coloring of the polyaryl ether was remarkably reduced by controlling the content to be ppm or less. Furthermore, it has been found that the presence of the general formula (1) significantly improves heat resistance and mechanical strength.

The present invention prepares an organic polar solution in which a dihalogenodiphenylsulfone compound and a dihydric phenol compound are dissolved in an organic polar solvent, and then polycondenses in the presence of an alkali metal compound in an inert gas atmosphere to give a compound of the general formula

[Chemical 2] (However, n is 1 or 2) 1% by weight or more of the total dihydric phenol is used, and the dissolved oxygen concentration in the organic polar solution is 4 ppm or less. It relates to a method for producing ether.

Specific examples of the dihydric phenol compound include:
For example, hydroquinone, catechol, resorcin,
In addition to 4,4′-biphenol, at least one hydrogen atom of bis (hydroxyphenyl) alkanes, dihydroxydiphenylsulfones, dihydroxydiphenylethers, or their benzene ring is a suitable substituent (eg, methyl group, ethyl group). Group, a lower alkyl group such as a propyl group, or a substituent such as a lower alkoxy group such as a methoxy group and an ethoxy group). Two or more kinds of the above dihydric phenol compounds may be mixed and used. In the present invention, it is preferable to use the compound represented by the general formula (1) as the dihydric phenol compound in an amount of 1% by weight or more based on the total dihydric phenol compound in order to improve heat resistance and mechanical properties of the produced polyaryl ether. Is essential to The dihydric phenol compound is preferably used in a substantially equimolar amount with the dihalogenodiphenyl sulfone compound. In order to control the molecular weight of the polyaryl ether to be produced, the dihydric phenol compound may be used in an equimolar amount to a slight excess amount or an excessive amount 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 in the present invention include sulfoxide solvents such as dimethyl sulfoxide and diethyl sulfoxide, amide solvents such as N, N-dimethylformamide and N, N-dimethylacetamide, and N-methyl-2-. Pyrrolidone-based solvents such as pyrrolidone and N-vinyl-2-pyrrolidone, piperidone-based solvents such as N-methyl-2-piperidone, 1,3-dimethyl-
Examples thereof include 2-imidazolinone-based solvents such as 2-imidazolinone and 1,3-diethyl-2-imidazolinone, hexamethylene sulfoxide, γ-butyrolactone, and sulfolane. Particularly, N-methyl-2-pyrrolidone and N, N-dimethylacetamide are preferably used.

The organic polar solution in the present invention can be prepared by a usual method. In the present invention, the dissolved oxygen concentration in the organic polar solution in which the dihalogenodiphenylsulfone compound and the dihydric phenol compound are dissolved is 4 ppm.
It is necessary to set the content below, and the preferable dissolved oxygen concentration is 3 ppm or less. When the concentration of dissolved oxygen in the organic polar solution exceeds 4 ppm, the polyaryl ether produced becomes remarkably colored, as can be seen from the results of Comparative Examples described later. There is no particular limitation on the method of reducing the dissolved oxygen in the organic polar solution to 4 ppm or less, and for example, a method of passing an inert gas such as nitrogen gas into the organic polar solution,
A method of flushing an organic polar solution in nitrogen gas, a method of degassing under reduced pressure, a method of deoxidizing a reducing agent that is inert to an organic polar solvent and has a reducing power that reduces only dissolved oxygen. A method of adding a large amount or a method of passing an organic polar solvent through a column filled with an oxygen scavenger can be mentioned. If necessary, the organic polar solvent may be separated and purified from the added reducing agent and its oxide. Examples of the reducing agent include salts of lower oxygen acids such as anhydrous sodium sulfite, sulfur compounds such as sodium sulfide, large electropositive metals such as alkali metals, magnesium, calcium, aluminum, zinc and the like. Amalgam, divalent iron, divalent tin, trivalent titanium,
Examples thereof include salts of metals in a low valence state such as divalent chromium.

The dihalogenodiphenyl sulfone compound is
General formula

[Chemical 3] (In the formula, X and X ′ are the same or different halogen atoms.). Preferred examples of the dihalogenodiphenyl sulfone compound include 4,4′-dichlorodiphenyl sulfone and 4,4′-difluorodiphenyl sulfone.

Examples of the alkali metal compound used 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 preferable. Before the polycondensation reaction, the alkali metal compound is added in an inert gas such as nitrogen gas in an amount of 60 to 60%.
You may heat-process for 1 minute or more under 500 degreeC and normal pressure or pressure reduction.

In the present invention, the oxygen concentration of an organic polar solution in which a dihydric phenol compound and a dihalogenodiphenyl sulfone compound are dissolved is adjusted to 4 ppm or less, and then an alkali metal compound is added to carry out a polycondensation reaction. Reaction temperature is usually 1
40-270 degreeC. Water generated 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. Examples of azeotropic dehydrating agents include benzene, toluene, xylene, and aromatic halogen compounds. At the end of the polycondensation, chloromethane may be blown into the reaction solution at 90 to 150 ° C., for example, as a polymer terminal stopper. 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, within the range where the polymer can be precipitated.

The precipitated solid is washed with a poor solvent and then dried to obtain a polyaryl ether powder. The molded article of this polymer has little coloration and has excellent heat resistance and mechanical strength.

For the measurement of dissolved oxygen in the present specification, the dissolved oxygen concentration was calculated by a dissolved oxygen meter "UC-12-SOL (for organic solvent)" (manufactured by Central Kagaku Co., Ltd.). The reduced viscosity (ηsp / c) used in this specification is obtained by the following equation. ηsp / c = (t−t ₀ ) / t ₀ / ct; transit time between marked lines in polymer viscometer (sec) t ₀ ; transit time between marked lines in viscometer of pure solvent (sec) C) Concentration of polymer solution (g / 100 ml solvent) The reduced viscosity was measured in N-methyl-2-pyrrolidone 30.
The temperature of the polymer solution was 0.5 g / 100 ml.

[0014]

【Example】

Example 1 720 g of 4,4′-dichlorodiphenyl sulfone, 510 g of bisphenol A and 40 of 4,4′-biphenol 40
g was dissolved in 3 l of N-methyl-2-pyrrolidone containing 2 ppm of dissolved oxygen, nitrogen gas was blown into the solution, and degassing under reduced pressure was performed to make the dissolved oxygen concentration 2 ppm,
Under a nitrogen atmosphere, 380 g of potassium carbonate was added, and the mixture was reacted at 180 ° C. for 9 hours under a nitrogen flow. After filtering the reaction solution, a polymer was precipitated in a powder form using ethanol. The polymer was washed with ethanol and dried under reduced pressure at 90 ° C overnight. The reduced viscosity (ηsp / c) of the obtained polymer was 0.50. This polymer was melt-molded at 330 ° C. and had a thickness of 0.25
mm film was made. Yellowness of this film (Y
I) was 4.0.

Example 2 730 g of 4,4'-dichlorodiphenyl sulfone, 140 g of hydroquinone and 230 of 4,4'-biphenol
g was dissolved in 3 l of N-methyl-2-pyrrolidone containing 2 ppm of dissolved oxygen, nitrogen gas was blown into the solution, and degassing under reduced pressure was performed to make the dissolved oxygen concentration 2 ppm,
Under a nitrogen atmosphere, 380 g of potassium carbonate was added, and the mixture was reacted at 180 ° C. for 8 hours under a nitrogen stream. After filtering the reaction solution, a polymer was precipitated in a powder form using ethanol. The polymer was washed with ethanol and dried under reduced pressure at 90 ° C overnight. The reduced viscosity (ηsp / c) of the obtained polymer was 0.57. This polymer was melt-molded at 340 ° C. and had a thickness of 0.25
mm film was made. Yellowness of this film (Y
I) was 5.5.

Example 3 730 g of 4,4'-dichlorodiphenyl sulfone, 140 g of hydroquinone and 300 of 4,4'-biphenol
A thickness of 0.25 was obtained in the same manner as in Example 2 except that g was used.
A mm-shaped film polymer was obtained. The obtained polymer had a reduced viscosity (ηsp / c) of 0.55 and the yellowness (YI) of the film was 4.8.

Example 4 730 g of 4,4'-dichlorodiphenyl sulfone, 140 g of hydroquinone and 230 of 4,4'-biphenol
g was dissolved in 3 l of N, N-dimethylacetamide having a dissolved oxygen concentration of 3 ppm, nitrogen gas was blown into the solution, and degassing under reduced pressure was performed to make the dissolved oxygen concentration 3 ppm.
A film-like polymer having a thickness of 0.25 mm was obtained in the same manner as in Example 2 except that the reaction was carried out at 0 ° C for 10 hours. This polymer was melt-molded at 330 ° C., the polymer obtained had a reduced viscosity (ηsp / c) of 0.52, and the yellowness (YI) of the film was 2.4.

Comparative Example 1 4,4'-dichlorodiphenyl sulfone 730 g, hydroquinone 140 g and 4,4'-biphenol 230
Example 1 except that g was dissolved in 3 L of N-methyl-2-pyrrolidone having a dissolved oxygen concentration of 6 ppm, polycondensation was performed at a dissolved oxygen concentration of 10 ppm, and the obtained polymer was melt-molded at 340 ° C. A film-like polymer having a thickness of 0.25 mm was obtained in the same manner as in. The polymer obtained had a reduced viscosity (ηsp / c) of 0.56 and the yellowness (Y) of the film.
I) was 15.4.

Comparative Example 2 4,4'-dichlorodiphenyl sulfone 730 g, hydroquinone 140 g and 4,4'-biphenol 230
g was dissolved in 3 l of N, N-dimethylacetamide having a dissolved oxygen concentration of 6 ppm, and the dissolved oxygen concentration of the solution was 9 ppm.
0.25 mm in thickness in the same manner as in Example 1 except that polycondensation was performed and the obtained polymer was melt-molded at 340 ° C.
A film polymer of The obtained polymer had a reduced viscosity (ηsp / c) of 0.55 and the yellowness of the film (Y
I) was 9.2.

Comparative Example 3 720 g of 4,4'-dichlorodiphenyl sulfone, 510 g of bisphenol A and 40 of 4,4'-biphenol 40
3 g of N-methylpyrrolidone having a dissolved oxygen concentration of 5 ppm
To obtain a film-like polymer having a thickness of 0.25 mm in the same manner as in Example 1 except that the dissolved oxygen concentration of the solution was adjusted to 10 ppm. The obtained polymer has a reduced viscosity (ηs
p / c) 0.52 and the yellowness index (YI) of the film was 10.1.

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

Claims (1)

[Claims] 1. An organic polar solution in which a dihalogenodiphenylsulfone compound and a dihydric phenol compound are dissolved in an organic polar solvent is prepared, and then polycondensed in the presence of an alkali metal compound in an inert gas atmosphere. 1] (However, n is 1 or 2) 1% by weight or more of the total dihydric phenol is used, and the dissolved oxygen concentration in the organic polar solution is 4 ppm or less. Method for producing ether.