JPH0586186A - Production of aromatic polyethersulfone - Google Patents

Abstract

PURPOSE:To rationalize the manufacturing process and suppress the side reaction to thereby obtain high-quality polyethersulfone by using 1,3-dimethyl-2- imidazolidinone as polymerization solvent in the polycondensation of a bisphenol having a specified structure and 4,4'-dichlorodiphenyl sulfone. CONSTITUTION:A polyethersulfone is produced by the polycondensation of a bisphenol of formula I (wherein Y is a direct linkage, -SO2-, -C/(CH2)2-or-O-) and 4-4'-dichlorodiphenyl sulfone of formula II, by using 1,3-dimethyl-2- imidazolidinone of formula III as the polymerization solvent.

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 polyether sulfone, which is a thermoplastic resin having excellent heat resistance.

[0002]

2. Description of the Related Art Polyethersulfone is an injection-molded circuit board, a support plate for disks such as optical disks and magnetic disks, an electrically insulating protective film, because of its excellent heat resistance, mechanical characteristics, electrical characteristics, and moldability. It is widely used in electric and electronic parts such as interlayer insulating films for integrated circuits, automobile parts, aircraft parts, and medical equipment parts. The polyether sulfone having such excellent properties requires a high reaction temperature in its production. The polymerization solvent used for this purpose is a high-boiling solvent, that is, dimethyl sulfone (boiling point 208 ° C., the same below), diphenyl sulfone (378 ° C.), dimethyl sulfoxide (189 ° C.), sulfolane (285 ° C.), N-methyl-2. -Pyrrolidone (204 ° C) and the like are used. However, when synthesizing polyethersulfone using these solvents, there was a problem that various restrictions or means for avoiding restrictions should be taken due to their physical and chemical properties. For example, for dimethyl sulfone (melting point 109 ° C.) and diphenyl sulfone (melting point 128 ° C.), in the isolation of the polymer after completion of the polymerization reaction, a means for adding another solvent is taken in order to avoid coagulation at a temperature not higher than the melting point of the polymerization solution ( JP-A-5
3-12991). The use of sulfolane is also disclosed in Canadian Patent No. 847963.
Polyether sulfone synthesized using this sulfolane is colored. Furthermore, since dimethyl sulfoxide reacts with an alkali metal salt of phenol, there arises a problem of suppression of side reaction in the polymerization using this.

[0003]

The object of the present invention is to obtain the following formula (1)

[0004]

[Chemical 5] (In the formula, Y is a direct bond, -SO _2- , -C (CH ₂ ).
_2- and -O-) and a bisphenol represented by the formula (2)

[0005]

[Chemical 6] In producing a polyether sulfone obtained by polycondensing 4,4′-dichlorodiphenyl sulfone represented by the following formula, it does not substantially react with monomers and is chemically inert, and is very easy to handle. It is to provide a new method for producing polyethersulfone using a polymerization solvent, rationalize the production process, suppress side reactions, and provide high-quality polyethersulfone.

[0006]

Means for Solving the Problems The inventors of the present invention have made extensive studies to solve the above problems, and as a result, formula (1) (Formula 7)

[0007]

[Chemical 7] (In the formula, Y is a direct bond, -SO _2- , -C (CH ₂ ).
_2- and -O-) and a bisphenol represented by the formula (2)

[0008]

[Chemical 8] When a polyether sulfone obtained by polycondensing 4,4′-dichlorodiphenyl sulfone represented by the formula (3)

[0009]

[Chemical 9] The present invention was completed by finding that it can be produced using 1,3-dimethyl-2-imidazolidinone represented by

That is, the present invention provides the bisphenol represented by the above formula (1) and the bisphenol represented by the above formula (2).
The present invention relates to a production method for producing polyethersulfone by polycondensation in 1,3-dimethyl-2-imidazolidinone represented by the above formula (3) using 4'-dichlorodiphenylsulfone as a polymerization solvent. In the above manufacturing method,
Examples of the bisphenol used include 4,4′-dihydroxybiphenyl, 4,4′-dihydroxydiphenyl sulfone, 2,2-bis (4-hydroxyphenyl) propane and 4,4′-dihydroxydiphenyl ether, which may be used alone or It is also used as a mixture of two or more kinds.

The molar ratio of bisphenols used in the production of the polymer of the present invention to 4,4'-dichlorodiphenyl sulfone is preferably in the range of 0.6 to 1.4. More preferably, it is in the range of 0.8 to 1.2,
In particular, for the purpose of obtaining a polymer having a high molecular weight, it is preferable to set the above molar ratio to around 1, and conversely, when polycondensation is performed outside the above molar ratio, a high molecular weight polymer is obtained. You will not be able to get it.

1,3 used for producing the polymer of the present invention
-Dimethyl-2-imidazolidinone is a good solvent for dissolving the raw material monomers and the formed polyether sulfone, but other solvents may be mixed and used as long as the characteristics are not impaired. Specific representative examples include dimethyl sulfoxide, sulfolane, diphenyl sulfone, N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, dimethyl sulfone, diphenyl ether, biphenyl, terphenyl, phenanthrene, Examples include naphthalene and diphenylmethane. The amount of the solvent used in the polycondensation is preferably in the range of 0.5 to 20 times the weight of the total monomers. The weight range is more preferably 2 to 8 times. If the amount of the solvent is less than 0.5 times the weight of all the monomers, the solubility of the monomer and / or polymer in the solvent decreases, and the operation such as stirring becomes very difficult, and the polycondensation reaction proceeds smoothly. It will not progress. Also,
If the amount of the solvent exceeds 20 times the weight of all the monomers, the concentration of the monomer in the solvent will be low and the polymerization rate will be low.

The bisphenols used to prepare the polymers of the present invention act as dialkali metal salts in the actual reaction. Therefore, the dialkali metal salt of bisphenol can be separately synthesized and used, or the reaction can be proceeded before or simultaneously with the polymerization reaction while forming a salt. Examples of the alkali metal salt include lithium, sodium, potassium and rubidium, and potassium and sodium are particularly preferable. Examples of the metal compound used for forming the dialkali salt include hydroxide, carbonate and hydrogen carbonate, and hydroxide and carbonate are particularly preferable. Therefore, in order to form a dialkali salt of bisphenol, potassium hydroxide, sodium hydroxide, potassium carbonate and sodium carbonate are preferable, and it is possible to use two or more of them without any problem. The amount of these alkali metal salts varies depending on the type, but is preferably in the range of 1 to 8 times the molar amount of bisphenol. More preferably, it is in the range of 2 to 4 times by mole. When the amount of the alkali metal salt is 1 mol or less with respect to bisphenol, the alkali metal salt of bisphenol cannot be sufficiently produced, and thus it becomes difficult to obtain a high molecular weight polymer. Moreover, an 8-fold molar excess or more is not economically advantageous.

The actual polymerization reaction in the production of the polymer of the present invention can be carried out in various modes shown below. For example, (1) bisphenols, an alkali metal salt and an azeotropic dehydration solvent are added in the presence of a polymerization solvent to generate azeotropic dehydration with an alkali metal salt of bisphenols, and then 4,4'-dichlorodiphenyl sulfone is added. In addition, a method of carrying out polymerization, (2) in the presence of a polymerization solvent, bisphenols, alkali metal salts, an azeotropic dehydration solvent, and 4,4 ′
-A method in which dichlorodiphenyl sulfone is added and azeotropic dehydration is carried out to carry out polymerization while forming an alkali metal salt of bisphenol, (3) An alkali metal salt of bisphenol is separately formed, and in the presence of a polymerization solvent, this and 4, A method of polymerizing by adding 4'-dichlorodiphenyl sulfone,
(4) A method in which an aqueous solution of an alkali metal salt of bisphenol is added to a polymerization solvent, and 4,4′-dichlorodiphenylsulfone is further added together with an azeotropic solvent to carry out the polymerization.

As is clear from the example of the above-mentioned polymerization method, dehydration by azeotropy uses an azeotropic solvent which is azeotropic with water, if necessary. Examples thereof include aromatic hydrocarbons such as benzene and toluenexylene, and halogenated aromatic hydrocarbons such as chlorobenzene and o-dichlorobenzene, but are not particularly limited as long as they are azeotropic with water. .. The amount of the azeotropic solvent used can be determined from the amount of water present in the reaction system and the azeotropic composition. In dehydration using an azeotropic solvent, water is distilled out together with the azeotropic solvent, the distillate is cooled and condensed, and the water and the azeotropic solvent are separated into two layers. If the separated azeotropic solvent layer is refluxed in the reaction system, the azeotropic solvent is effectively used, and thus dehydration can be completed without using a large excess of the azeotropic solvent. The time required for azeotropic dehydration also varies depending on the amount of water present in the reaction system, the amount of azeotropic solvent used, etc., but from a practical point of view, it is preferably performed within 10 hours, and further completed within 5 hours. It is even more preferable.

The temperature of the polymerization reaction in producing the polymer of the present invention varies depending on the kind of the raw material components of the reaction, the type of the polymerization reaction, etc., but is usually in the range of 80 to 225 ° C., preferably 120 to 225. It is carried out in the range of ° C. When the reaction temperature is lower than the above temperature range, the intended polymerization reaction hardly proceeds at a rate practically practical, and it is difficult to obtain a polymer having a required molecular weight. The reaction may be carried out at a constant temperature, or the temperature may be gradually changed or the temperature may be changed stepwise.

In the production of the polymer of the present invention, the time required for the reaction varies greatly depending on the type of reaction raw material components, the type of polymerization reaction, the type of reaction temperature, etc., but is usually in the range of 10 minutes to 100 hours. Yes, it is preferably carried out for 30 minutes to 24 hours. As a reaction atmosphere, oxygen is preferably not present, and good results can be obtained by performing the reaction in nitrogen or another inert gas. Alkali salts of bisphenols are easily oxidized when heated in the presence of oxygen, which hinders the intended polymerization reaction and makes it difficult to increase the molecular weight, and also causes coloring of the polymer.

In the production of the polymer of the present invention, the reaction product is usually cooled to stop the polymerization reaction. However, in order to stabilize any phenoxide groups that may be present at the ends of the polymer, aliphatic halides,
Addition reaction of an aromatic halide or the like may be carried out if necessary. Specific examples of the above-mentioned halides include methyl chloride, ethyl chloride, methyl bromide, 4-chlorodiphenyl sulfone, 4-chlorobenzophenone, bis (4-chlorophenyl) sulfone,
p-chloronitrobenzene etc. can be mentioned.

[0019]

The present invention will be described in detail with reference to the following examples and comparative examples. The logarithmic viscosity ηinh in the following examples is
Using a mixed solvent of p-chlorophenol / phenol (weight ratio 9/1), a solution having a polymer concentration of 0.5 g / dl was measured at 35 ° C. and determined according to the following equation. (In the above, t ₁ is the polymer solution flow time (seconds), t ₂ is the solvent flow time (seconds), and C is the polymer solution concentration (g / dl). The glass transition temperature by DSC is Shimadzu. DT-40 series DSC manufactured by Seisakusho Co., Ltd.
-41M under nitrogen stream, heating rate 16 ° C / min
It was measured under the conditions of. The infrared absorption spectrum was measured using IRA-1 manufactured by JASCO Corporation. The 5% weight loss temperature is DT-40 series DT manufactured by Shimadzu Corporation.
The measurement was performed using G-40 under an air flow at a temperature rising rate of 10 ° C / min.

Example 1 25.03 g (0.1 mol) of 4,4'-dihydroxydiphenyl sulfone was placed in a 500 ml flask equipped with a stirrer, a thermometer, a condenser, a distillate separator and a nitrogen inlet tube. , 50 ml of toluene, 125.4 g of 1,3-dimethyl-2-imidazolidinone, and 28.0 g of 40% aqueous potassium hydroxide solution were introduced, and nitrogen gas was passed while stirring to replace the whole reaction system with nitrogen. The mixture was heated to 130 ° C while passing nitrogen gas. With the temperature of the reaction system rising, the reflux of toluene was started, water in the reaction system was removed by azeotropic distillation with toluene, and azeotropic dehydration was carried out at 130 ° C. for 4 hours while returning toluene to the reaction system. After this, 4, 4'-
Dichlorodiphenyl sulfone 28.7 / g in toluene 2
It was added to the reaction system together with 0 g, and the reaction system was heated to 150 ° C. The reaction was performed for 4 hours while distilling toluene to obtain a highly viscous brown solution. The temperature of the reaction solution was cooled to room temperature, and the reaction solution was discharged into 500 g of methanol to deposit a polymer powder. The polymer powder was collected by filtration and transferred to a beaker. To this, 500 g of water was added, 1N hydrochloric acid was further added, and the slurry solution was acidified by adding pH 3 to 4. After collecting the polymer powder by filtration, the polymer powder was washed twice with 500 g of water. Further methanol 500
It was washed with g and dried under reduced pressure at 150 ° C. for 12 hours. The obtained polymer powder was white powder and the yield was 46.40 g.
(Yield 99%). The inherent viscosity of the obtained polymer powder was 0.80 dl / g. Also polymer powder KB
As a result of measuring the infrared absorption spectrum by the r method, 15
90, 1490, 1250, 1160, 1110 cm ^-1
Commercially available polyether sulfone (trade name Victrex, 4100
P, manufactured by ICI) was observed. Further, the DSC of the polymer powder was measured, and as a result, the glass transition temperature was 22.
It was 4 ° C. The 5% weight loss temperature was 510 ° C.

Example 2 In Example 1, 25.03 g (0.1 mol) of 4,4'-dihydroxydiphenylsulfone was added to 22.83 g of 2,2-bis (4-hydroxyphenyl) propane.
(0.1 mol), except that the weight of 1,3-dimethyl-2-imidazolidinone was changed from 125.4 g to 120.3 g, the same operation as in Example 1 was carried out to obtain a white powder. 44.20 g (yield 99%) of polymer powder was obtained.
The polymer powder obtained had an inherent viscosity of 0.75 dl / g, and the infrared absorption spectrum measured by the KBr method was 2900, 1590, 1490, 1250, 116.
An absorption spectrum was observed at ⁰ , 1110 cm ^-1 . The glass transition temperature measured by DSC was 191.
C. and 5% weight loss temperature was 488.degree.

Example 3 In Example 1, 40% aqueous potassium hydroxide solution 28.
46. The operation was performed in the same manner as in Example 1 except that 50 g of a 40% sodium carbonate aqueous solution was used instead of 0 g.
38 g of white powder was obtained as a polymer powder. The obtained polymer powder had an inherent viscosity of 0.79 dl / g, an infrared absorption spectrum was exactly the same as in Example 1, and the glass transition temperature measured by DSC showed 225 ° C. The 5% weight loss temperature was 509 ° C.

Comparative Example In Example 1, 1,3-dimethyl-as a polymerization solvent
The procedure of Example 1 was repeated, except that 2-imidazolidinone was changed to sulfolane, to obtain 46.38 g (yield 99%) of polymer powder. The obtained polymer powder had a light brown color and was clearly colored as compared with the polymer powder obtained in Example 1. The logarithmic year of the polymer powder obtained in this comparative example was 0.78 dl / g, and DSC
The measurement result of the glass transition temperature was 222 ° C.
In addition, the 5% weight loss temperature is 490 ° C., which is clearly Example 1.
The value was lower than that of the polymer powder obtained in.

[0024]

Industrial Applicability The production method of the present invention is a production method capable of not only solving various problems that have occurred during the production of aromatic polyether sulfones, but also of rationalizing the conventional production process. .. Further, it is a production method that can be used without any modification and alteration of the existing production equipment, and is very effectively used for the production of polyether sulfone. Furthermore,
Since there are no side reactions in the polymerization and the like, the quality of the obtained polyether sulfone is improved and is uniform, so that it can be effectively used for the production of polyether sulfone.

[Brief description of drawings]

FIG. 1 is an infrared absorption spectrum diagram of the polymer powder obtained in Example 1.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshiyuki Kataoka 1190 Kasama-cho, Sakae-ku, Yokohama-shi, Kanagawa Mitsui Toatsu Chemical Co., Ltd. (72) Akihiro Yamaguchi 1190 Kasama-cho, Sakae-ku, Yokohama, Kanagawa Mitsui Toatsu Chemical Within the corporation

Claims (2)

[Claims] 1. Formula (1) (Formula 1) (In the formula, Y is a direct bond, -SO _2- , -C (CH ₂ ).
_2- and -O-) and a bisphenol represented by the formula (2) (Chemical Formula 2) In the method for producing a polyether sulfone obtained by polycondensing 4,4′-dichlorodiphenyl sulfone represented by the formula, the polymerization solvent is represented by the formula (3) (Chemical Formula 3): A method for producing a polyether sulfone, which comprises using 1,3-dimethyl-2-imidazolidinone represented by: 2. The following formula (1) (formula 4) according to claim 1 The method for producing a polyethersulfone according to claim 1, wherein Y is —SO ₂ —.