JPS63170417A - Production of high-molecular weight aromatic polyether - Google Patents

Abstract

PURPOSE:To obtain the titled polymer useful as precision parts, having excellent heat resistance, mechanical strength, etc., by polymerizing dihydric phenol adduct of two alkaline metallic salts with a dihalogenobenzenoid compound in the presence of a high-purity imidazolidinone derivative. CONSTITUTION:(A) A dihydric phenol (e.g. 4,4'-dihydroxybenzophenone, etc.) shown by formula I (Y is 1-5C alkylene, etc.; R<1> and R<2> are CH3, OCH3, etc.; n1 and n2 are 0-4) is dissolved in (B) a solvent of a compound shown by formula II (R<5> and R<6> are CH3, etc.) having purity by gas chromatography analysis of >=99.995 area, reacted with (C) an alkali metallic salt-forming agent (e.g. sodium, etc.) and polymerized in the presence of (D) a dihalogenobenzoid show by formula III (X and X' are halogen; Z is OS2, etc.; R<3> and R<4> are CH3, etc.; n3 and n4 are 0-4) to give the aimed polymer having >=0.35 reduced viscosity.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a high molecular weight aromatic polyether with an improved degree of coloration.

(Industrial Application Field) Thermoplastic aromatic polyethers, especially polysulfone, polyethersulfone, and polyetherketone, have excellent heat resistance, mechanical performance, and chemical resistance, and are highly commercially practical. be.

(Prior art and its problems) Various methods have been proposed for producing aromatic polyethers. A typical method is
As disclosed in No. 7799 and Japanese Patent Publication No. 45-21318, a dialkali metal salt of a dihydric phenol produced from a dihydric phenol and an alkali metal hydroxide and a dihalogenobenzenoid compound are combined with a high boiling point sulfoxide or This is a method of reacting in a sulfone solvent (eg dimethyl sulfoxide, sulfolane). However, these solvents do not have sufficient alkali resistance;
In the presence of an alkali, it decomposes at high temperatures, causing the resulting polymer to become significantly colored.

Furthermore, in such polycondensation reactions, the molecular weight of the resulting polymer is increased by adjusting the molar ratio between the alkali metal di-salt of dihydric phenol and the dihalogenobenzenoid compound; Indeed, there is a problem in that it is difficult to obtain a high molecular weight polymer due to the influence of the accuracy of raw material preparation, impurities in the organic highly polar inert solvent, especially the content of polymerization inhibitors, etc.

(Means for Solving the Problems) As a result of intensive studies to solve these problems, the present inventors surprisingly found that using a highly purified 2-imidazolidinone derivative as a reaction solvent solves the above problems. It was discovered that all the problems were solved and that an aromatic polyether with a low degree of coloration and a high molecular weight could be obtained, and the present invention was completed.

That is, the present invention relates to the general formula (I) (Y is a direct bond or an alkylene or alkylidene group having 1 to 5 carbon atoms, or a cycloalkylene or cycloalkylidene group having 5 to 15 carbon atoms, or -O+ , -co-,5
o2-, -s-represents a neutral group.

R1, R2 are -CH3, -C2H5, -CH(CH3)
2゜-0CH3, -QC2H5, R
1 and R2 may be the same or different.

n1tn2 represents an integer from 0 to 4. ) and the alkali metal di-salt of a dihydric phenol obtained by reacting the dihydric phenol represented by the formula (II) with an alkali metal salt-forming agent of the dihydric phenol and the general formula (II) (X, X' are halogen atoms and are the same) but may be different, being in the ortho or para position to 2.

2 is -802- or -〇〇-.

R3, R4 are -CH3, -C2H5, -CH(CH3)
2゜-0CH3, -0C2H5, R
3 and R4 may be the same or different.

n3pn4 represents an integer from 0 to 4. ) with a dihalogenobenzenoid compound represented by In the polycondensation step of the di-salt and the dino-10genoid compound, gas chromatography analysis of the general formula (III) (R5 and R6 represent either -CH3 or -C2H5) revealed that 99° 99
Reduced viscosity (measured with a 1wt% polymer solution in N,N'-dimethylformamide at 25°C) is 0.35 or more, characterized by using a highly pure organic highly polar inert solvent with a content of 5 area% or more. This is a method for producing a high molecular weight aromatic polyether with little coloring.

The dihydric phenol used in the present invention is not particularly limited as long as it is a compound represented by the general formula (I), but for the purpose of imparting heat resistance to the resulting polymer, 4,4'-
Dihydroxybenzophenone, 4,4-dihydroxydiphenylsulfone, 4゜4-dihydroxybiphenyl,
2,2-bis-(4-hydroxyphenyl)propane,
Bis-(4-hydroxyphenyl)methane and the above-mentioned dihydric phenol substituted with a methyl group at the ortho position are preferred. Among these, the compound represented by (Y is the same as the above general formula (I)) is particularly preferred.

The alkali metal salt-forming agent for dihydric phenol mentioned in the present invention is one that reacts with dihydric phenol to form an alkali metal di-salt of dihydric phenol, such as an alkali metal, an alkali metal hydride, an alkali metal Examples include hydroxides, alkali metal carbonates, alkali metal hydrogen carbonates, alkali metal sulfides, alkali metal hydrogen sulfides, and alkali metal alkoxides. Specifically, sodium, potassium, sodium hydride,
Potassium hydride, sodium hydroxide, potassium hydroxide,
Sodium carbonate, potassium carbonate, sodium bicarbonate,
Potassium bicarbonate, sodium sulfide, potassium sulfide, sodium hydrogen sulfide, potassium hydrogen sulfide, sodium methoxide.

These include potassium methoxide, sodium ethoxide, potassium ethoxide, etc.

These dihydric phenol alkali metal salt forming agents may be used in a solid state or in the form of an aqueous solution.

The amount of the alkali metal salt forming agent for dihydric phenol used in the present invention is 5.0% equivalent excess relative to the hydroxyl group of dihydric phenol. An equivalent excess of .1 to 1.0% is preferred.

Examples of high purity organic highly polar inert solvents with a purity of 99.995 area % or more in gas chromatography analysis used in the present invention include 1, 3. dimethyl-2-imidazolidinone or 1,3-diethyl-2-imidazolidinone,
Although 1-ethyl-3-methyl-2-imidazolidinone is used, it is preferable to use 1,3-dimethyl-2-imidazolidinone, which is easily available.

Examples of methods for obtaining the above-mentioned high-purity imidazolidinone derivatives include distillation separation methods, extraction separation methods, adsorption separation methods, and the like. Although any purification method may be used, a method of distillation in the presence of an alkali is preferred. Distillation in the presence of alkali can be used to convert imidazolidinone derivatives into alkali metals, alkaline earth metals, alkali metal hydrides, alkali metal hydroxides, alkaline earth metal hydroxides, alkali metal carbonates, alkali metal hydrogen carbonates or Alkali metal alkoxides, specifically sodium.

Potassium, calcium, sodium hydride, potassium hydride, sodium hydroxide, potassium hydroxide, calcium hydroxide, sodium carbonate, potassium carbonate.

It is preferable to add 0.5 to 10% by weight of sodium hydrogen carbonate, potassium hydrogen carbonate, sodium methoxide, potassium methoxide, sodium ethoxide, potassium ethoxide, etc. Note that the distillation may be performed at normal pressure or under reduced pressure.

The amount of the highly pure organic highly polar inert solvent used in the present invention is usually in the range of 0.05 to 30 times the weight of the dihydric phenol used. More preferably, it is used in a range of 0.1 to 15 times. If the amount of organic highly polar inert solvent with a purity higher than the above range is less, the effect as a solvent will not be recognized, and in particular, the produced polymer will precipitate even if it has a low molecular weight, which may impede practical use. Certain high molecular weight polymers become unobtainable.

On the other hand, if the amount of the highly pure organic highly polar solvent is increased beyond the above range, the concentration of 7mer will decrease, so a higher temperature and longer reaction time will be required to obtain a practical high molecular weight polymer. Not practical.

The actual polymerization reaction in the present invention can be concretely carried out, for example, in the format shown below.

For example, in the presence of a highly pure organic highly polar inert solvent as defined in the present invention, a dihydric phenol and an alkali metal di-salt forming agent of the dihydric phenol are reacted within the molar ratio range as defined in the present invention. After removing the resulting low-boiling compounds such as water, hydrogen sulfide, methanol, ethanol, or hydrogen gas by heating or azeotropic dehydration, a dihalogenobenzenoid compound is added and polymerized.

The dihalogenobenzenoid compound used in the present invention is not particularly limited as long as it is a compound represented by the general formula (II); , 4,4'-dichlorodiphenylsulfone, 4゜4'-difluorodiphenylsulfone, 4,4'-dichlorobenzophenone, 4.4'
-Difluorobenzophenone and the above-mentioned dihalogenobenzenoid compounds substituted with a methyl group at the ortho position are preferred.

Among them, (2 is the same as the above general formula (I).) Particularly preferred are compounds represented by:

The amount of the dihalogenobenzenoid compound used in the present invention is preferably within the range of 90 to 110 mol% based on the dihydric phenol. In order to obtain a polymer with higher molecular weight, it is preferable to use it within the range of 98 to 103 mol%.

The actual temperature of the polymerization reaction in the method of the present invention varies depending on the type of reaction raw material components, the type of polymerization reaction, etc., but is usually in the range of 80 to 400°C, preferably 100 to 400°C.
It is carried out in the range of 350°C. If the reaction temperature is lower than the above-mentioned temperature range, the desired polymerization reaction will hardly proceed at a rate that can be used practically, and it will be difficult to obtain a polymer with the required molecular weight. On the other hand, when the reaction temperature is higher than the above range, side reactions other than the desired polymerization reaction cannot be ignored, and the resulting polymer becomes significantly colored. Further, the reaction may be carried out at a constant temperature, or the temperature may be gradually changed or the temperature may be changed stepwise.

The time required for the polymerization reaction in the method of the present invention varies greatly depending on the type of reaction raw materials, type of polymerization reaction, reaction temperature, etc., but is usually in the range of 10 minutes to 100 hours, preferably 30 minutes to It will be carried out over a 24 hour period.

The reaction atmosphere in which the reaction is carried out in the method of the present invention is preferably free of oxygen, and good results are obtained when the reaction is carried out in nitrogen or other inert gas.

Alkali metal di-salts of dihydric phenols are easily oxidized when heated in the presence of oxygen, hindering the desired polymerization reaction, making it difficult to increase the molecular weight, and also causing coloration of the resulting polymer.

In the method of the present invention, in order to stop the polymerization reaction, it is usually sufficient to cool the reactants. However, in order to stabilize phenoxide groups that may be present at the ends of the polymer, an aliphatic halide, an aromatic halide, or the like may be added and reacted as necessary. Specific representative examples of the halides include methyl chloride, ethyl chloride, methyl bromide, 4-chlordiphenylsulfone, 4-chlorobenzophenone,
Examples include 4,4-dichlorodiphenylsulfone and p-chloronitrobenzene.

Known methods can be applied to separate and purify the polymer after the polymerization reaction is completed. For example, after filtering out the salt (alkali halide) precipitated in the reaction solvent, the filtrate, which is a polymer solution, is usually added dropwise to the polymer non-solvent, or conversely, the polymer non-solvent is added to the polymer solution. By adding it to the solution, the desired polymer can be precipitated. Typical examples of non-solvents commonly used for polymers include methanol, ethanol, isopropanol, acetone, methyl ethyl ketone, water, etc. These can be used alone or as a mixture of two or more. Good too.

The polymer obtained by the present invention has excellent heat resistance,
Due to its stability and high mechanical strength, it can be used for electrical insulation, heat-resistant parts, cooking utensils, coating materials, precision parts, etc.

The present invention will be explained in detail in the following Examples and Comparative Examples, but the present invention is not limited thereto.

(Example) [Purification of commercially available 1,3-dimethyl-2-imidazolidinone] Commercially available l, 3. Dimethyl-2-imidazolidinone (DMI
57 g of 50% aqueous sodium hydroxide solution was added to 2859 g of ) and vacuum distilled under the conditions shown in Table 1 using a 40 mm Φ 20-stage holder and Shaw's salt.

The distillation results are also shown in Table 1, and the gas chromatography analysis shown in Figure 1 shows that high purity DMI with a total content of components other than DMI of 50 ppm or less in area% of the gas chromatogram was obtained. I can see that.

[Synthesis of aromatic polyether 1 48.55 ml in a 11 SUS flask equipped with a stirrer, a nitrogen inlet tube, a thermometer and a condenser with a receiver at the tip
% potassium hydroxide aqueous solution 47.06 g (potassium hydroxide 0.4072 mol), 4,4'-dihydroxydiphenyl sulfone 50.80 g (0,2028 mol), high purity DMI (fr -4 in Table 1) 372 .0g and water 2
Add 2.92g and stir at room temperature until uniform. Next, raise the temperature to 200'C and stir at 200°C for 20 minutes.

During this time, about 90% of the theoretical amount of water, including produced water, is distilled out. Next, the mixture is heated until DMI is distilled out, and about 90 g of DMI is distilled out. As a result, 98% of the theoretical dehydration amount
The above amount of water is distilled off, resulting in a substantially anhydrous state.

Next, 4,4'-dichlorodiphenylsulfone 58°5
7g (0,2038 mol) of high purity DMI (f of Table 1)
r-4) Add the solution dissolved in 100゜0g,
Polymerization was carried out at 6°C for 6 hours. After that, the reaction solution was heated to 150°.
Cool to C and add methyl chloride gas to 150 ml/m
The polymerization was stopped by blowing at a flow rate of in for 30 minutes.

The reaction solution was cooled to room temperature, potassium chloride precipitated in the reaction solution was removed by filtration, and the filtrate was poured into a large amount of MeOH to precipitate the polymer. Filter the precipitated polymer,
After washing with water several times, it was heated and dried at 150'C under reduced pressure.

The yield of the resulting polymer was 95%, the reduced viscosity measured in N,N-dimethylformamide (1.0 g of polymer in 100 ml at 25 °C) was 0.71 dl/g, and the polymer had a reduced viscosity of 1% N,N. - The dimethylformamide solution was almost colorless.

(Comparative Example) An experiment was conducted using the same raw material ratio and production method as in the example except that commercially available DMI (Table 1 prepared DMI) was used as DMI.

GC analysis conditions - Equipment: Shimadzu GC-9A Column: PEG20M20%/CP (A
W) Glass 2mCT; 170°C I T ; 230'C Detector; FID (H2O, 7kg/cm2Ai
rO, 5kg/cm2) flow rate; He 1.7kg/
cm2 Sensitivity; 102 Injection volume; lpl The yield of the produced polymer was 95% and the reduced viscosity measured in N,N-dimethylformamide (25 °G, 1.0 g of polymer in 100 ml) was 0.38 dl/ g
, 1% N of the polymer.

The N-dimethylformamide solution was pale yellow.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing gas chromatography analysis conditions for DMI and a gas chromatogram of DMI. FIG. 2 is a gas chromatogram of DMI used in Examples and Comparative Examples.

Claims (1)

[Claims] 1) General formula (I) ▲ Numerical formulas, chemical formulas, tables, etc. ▼... (I) (Y is a direct bond or an alkylene or alkylidene group having 1 to 5 carbon atoms, or represents a cycloalkylene or cycloalkylidene group having 5 to 15 carbon atoms, or any group of -O-, -SO_2-, -S-. R^1 and R^2 are -CH_3, -C_2H_5 , -CH
(CH_3)_2, -OCH_3, -OC_2H_5, and R^1 and R^2 may be the same or different. _n__1 and _n__2 represent integers from 0 to 4. ) and the alkali metal di-salt of dihydric phenol obtained by reacting the dihydric phenol with an alkali metal salt-forming agent and the general formula (II) ▲Mathematical formulas, chemical formulas, tables, etc. are available▼ ...(II) (X and X' are halogen atoms, which may be the same or different, and are located at the ortho or para position with respect to Z. Z is -SO_2- or -CO-. R^3 , R^4 is -CH_3, -C_2H_5, -CH
(CH_3)_2, -OCH_3, -OC_2H_5, and R^3 and R^4 may be the same or different. _n__3 and _n__4 represent integers from 0 to 4. ) is reacted with a dihalogenobenzenoid compound represented by formula (III) ▲ Formula, There are chemical formulas, tables, etc. ▼... (III) (R^5, R^6 represent either -CH_3, -C_2H_5.) Gas chromatography analysis shows 99.99
It is characterized by using a highly pure organic highly polar inert solvent having a content of 5 area% or more [reduced viscosity (measured with a 1wt% polymer solution in N,N'-dimethylformamide at 25°C) of 0.35 or more. ] A method for producing a high molecular weight aromatic polyether with little coloring. 2) The production according to claim 1, wherein the dihydric phenol represented by the general formula (I) is a compound represented by ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (Y is the same as above) Method. 3) The dihalogenobenzenoid compound represented by general formula (II) is a compound represented by: ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (Z is the same as above) manufacturing method. 4) The manufacturing method according to claim 1, wherein the organic highly polar inert solvent represented by general formula (III) is 1,3-dimethyl-2-imidazolidinone.