JPH0528245B2 - - Google Patents

Description

[Detailed description of the invention]

INDUSTRIAL APPLICATION FIELD OF THE INVENTION The present invention relates to an improved method for producing crystalline aromatic polyetherketones. More specifically, the present invention provides an industrially advantageous method for producing a high-molecular-weight, highly crystalline aromatic polyetherketone with excellent heat resistance, chemical resistance, mechanical strength, etc. using a specific reaction solvent. It is related to. Background Art In recent years, crystalline aromatic polyetherketones in which phenylene groups are linked via ether groups and ketone groups have been used for molding in various fields because they have excellent heat resistance, chemical resistance, mechanical strength, etc. It is attracting attention as a material. As a method for producing this aromatic polyether ketone, for example, a dialkali metal salt of bisphenol containing a ketone group and a dihalogeno compound containing a ketone group are mixed in the presence of an aromatic sulfone at 250 to
A method of heating to a temperature of 400°C (Japanese Patent Publication No. 57-22938), in which a halophenol containing a ketone group is mixed with an alkali metal carbonate, N-methylpyrrolidone,
200 in aliphatic sulfones or aromatic sulfonates
Method of heating to a temperature of ~400°C (US Patent No. 4113699)
(No. No. Specification) etc. are known. By the way, in order to produce a high molecular weight polymer, it is generally necessary to proceed with the reaction in a polymerization medium that dissolves the produced polymer, but in the case of crystalline aromatic polyether ketone, this is not possible. Insoluble at low temperatures in polymerization media such as 300℃
Polymerization must be carried out at higher temperatures. Therefore, in a method for producing a high molecular weight crystalline aromatic polyetherketone, it is important to select a polymerization solvent that is stable even at high temperatures and has appropriate polarity. Conventionally, such polymerization solvents include aliphatic sulfone, aromatic sulfone, N
-Methylpyrrolidone etc. are used, but even if aromatic sulfone is used, a long reaction time is required at high temperature especially when the purpose is to obtain a polymer with high crystallinity and high melting point. N-methylpyrrolidone and aliphatic sulfones such as sulfolane are thermally unstable, and their ability as polymerization solvents is inferior to that of aromatic sulfones. Because of their inferiority, it has been difficult to obtain a high molecular weight, highly crystalline aromatic polyether ketone even if these are used. Problems to be Solved by the Invention The first object of the present invention is to provide an improved production method for obtaining a high molecular weight, highly crystalline aromatic polyether ketone having excellent heat resistance, chemical resistance, mechanical strength, etc. The purpose is to provide a method. A second object of the present invention is a method for easily producing a high-molecular-weight, highly crystalline aromatic polyetherketone by using a specific polymerization solvent that is stable at high temperatures and has appropriate polarity. The goal is to provide the following. Means for Solving the Problems As a result of intensive research to achieve the above object, the present inventors found that certain aromatic ketone compounds were used as a polymerization solvent when producing crystalline aromatic polyether ketone. The inventors have discovered that the object can be achieved by using the present invention, and have completed the present invention based on this knowledge. That is, the present invention involves condensation polymerization of at least one aromatic dihydroxy compound component and at least one dihalogeno aromatic ketone component, or at least one monohydroxy monohalogeno aromatic ketone component, in a solvent. When producing crystalline aromatic polyetherketone by condensation polymerization, as a solvent, the general formula (X in the formula is an oxygen atom or a ketone group, R, R',
R'' and R are each a hydrogen atom and have 1 to 3 carbon atoms
an alkyl group or a phenyl group, which may be the same or different, and m and n
(one of which is 1 and the other is 0 or 1) provides a method for producing a crystalline aromatic polyether ketone having a reduced viscosity of 0.6 or more It is something. In the condensation polymerization reaction in the method of the present invention, for example, an aromatic dihydroxy compound having a free hydroxyl group is used as a component having a free hydroxyl group, and a substantially equimolar mixture of this and a dihalogeno aromatic ketone component is Heating in the presence of an alkali in a predetermined solvent, or heating a substantially equimolar mixture of an alkali metal salt thereof as an aromatic dihydroxy compound component and a dihalogeno aromatic ketone in a predetermined solvent. Alternatively, a monohydroxymonohalogenoaromatic ketone component having a free hydroxyl group may be used and heated in a predetermined solvent in the presence of an alkali, or a monohydroxymonohalogenoaromatic ketone may be heated in the presence of an alkali. This can be carried out by using an alkali salt and heating it in a predetermined solvent. Among these methods, an aromatic dihydroxy compound and a dihalogeno aromatic ketone are thermally polymerized in the presence of an alkali metal carbonate or bicarbonate as an alkali, or a monohydroxy monohalogeno aromatic ketone is Particularly advantageous is a method of polymerizing by heating. The aromatic dihydroxy compound component used as a raw material in the method of the present invention includes a dihydric phenol represented by the general formula HO-Ar-OH () (Ar is an aromatic residue) and its alkali salt. Examples of these include mononuclear divalent phenols such as hydroquinone, dihydroxy polyphenyl such as 4,4'-dihydroxybiphenyl, and 1,1'-bis(4-hydroxyphenyl).
Propane, bis(4-hydroxyphenyl)methane, 4,4'-dihydroxybenzophenone, 4,
4'-dihydroxydiphenyl ether, 4,4'-
Examples include bisphenols such as dihydroxydiphenyl sulfide, 4,4'-dihydroxyterephthalophenone, and 4,4'-dihydroxyisophthalophenone, their nuclear substituted products, and their alkali salts. This alkali salt is obtained by reacting the divalent phenol of the general formula () with an alkali such as an alkali metal hydroxide according to a conventional method. Particularly preferred among such aromatic dihydroxy compound components are:
Hydroquinone, 4,4'-dihydroxybenzophenone. These dihydric phenols or alkali salts thereof may be used alone or in a mixture of two or more. Next, the dihalogeno aromatic ketone component to be condensed with this aromatic dihydroxy compound component is as follows:
For example, the general formula A dihalogenobenzenoid compound represented by (which is a bonded halogen atom) is used. Among such dihalobenzenoid compounds,
Preferably, the general formula (X has the same meaning as above, Z is an ether group,
Examples include compounds represented by a thioether group, a carbonyl group, a sulfone group, or a divalent alkylene group, x and y are integers of 1 to 3. Examples of such compounds include 4,4'-difluorobenzophenone, 2,4'-difluorobenzophenone, 4,4'-dichlorobenzophenone, and bis-1,4-(4-fluorobenzoyl).
Benzene, bis-1,3-(4-chlorobenzoyl)benzene, bis-1,4-(4-chlorobenzoyl)benzene, bis-4,4'-(4-chlorobenzoyl)biphenyl, bis-4,4 ′-(4-
Examples include chlorobenzoyl) diphenyl ether. These dihalogeno aromatic ketones may be used alone or in combination of two or more. Among the dihalobenzenoid compounds of the general formula (), those in which the halogen atom is bonded to the para position relative to the bonding position of the ketone group are particularly advantageous for obtaining a polymer with a high melting point and high crystallinity. It is. In addition, using fluorine as a halogen atom is advantageous in that it has higher reactivity than chlorine, makes it easier to obtain high molecular weight products, and is less likely to cause side reactions such as coloring or crosslinking of the polymer. be. Particularly preferred are 4,4'-difluorobenzophenone and bis-1,4'-(4-fluorobenzoyl)benzene (4,4'-difluoroterephthalophenone). Next, the monohydroxy monohalogeno aromatic ketone component used as a raw material for another method is represented by the general formula: There are halophenols and their alkali salts containing at least one benzophenone unit; examples of such are 4-fluoro-4'-hydroxybenzophenone, 4-chloro-
4'-hydroxybenzophenone, 4-(4-fluorobenzoyl)-4'-hydroxybiphenyl,
Examples include 4-(4-fluorobenzoyl)-4'-hydroxydiphenyl ether and alkali metal salts thereof. Further, the alkali salt of halophenol used in the present invention can be obtained by a known method, for example, the method of reacting halophenol with an alkali metal hydroxide as described above. These halophenols or alkali salts thereof may be used alone or in combination of two or more. It is advantageous for the halogen atom of these halophenols or their alkali salts to be fluorine as in the case of the dihalobenzenoid compounds, and 4-fluoro-4'-hydroxybenzophenol is particularly preferred. Non or its alkali metal salts are used. In the method of the present invention, the general formula It is necessary to use an aromatic ketone compound represented by 1,3-dibenzoylbenzene (isophthalophenone), 1,
4-dibenzoylbenzene (terephthalophenone), 4-benzoyl diphenyl ether, 4,
4'-dibenzoyl diphenyl ether, 4,4'-
Examples include dibenzoylbenzophenone.
Among these, 1,3-dibenzoylbenzene and 1,4-dibenzoylbenzene are preferred. These solvents may be used alone or in combination of two or more. Furthermore, if desired, other solvents such as diphenyl sulfone, xanthone, etc. can be used in combination within a range that does not impair the object of the present invention. In the method of the present invention, when the dihydric phenol of the general formula () is used as the aromatic dihydroxy compound component, or when the halophenol of the general formula () is used as the monohydroxy monohalogeno aromatic ketone component, It is necessary to carry out the reaction in the presence of an alkali. As this alkali, for example, alkali metal hydroxides, carbonates, bicarbonates, fluorides, hydrides, alkoxides, alkylated products, etc. are used. Among these, carbonates and bicarbonates of alkali metals are preferred, and potassium, sodium, and mixtures thereof are preferred as alkali metals. According to the method of the present invention, when the dihydric phenol of the general formula () and the dihalogenobenzenoid of the general formula () are condensed, the general formula ()
A predetermined amount of dihydric phenol, dihalobenzenoid, and alkali are added to the aromatic ketone compound represented by the formula, and the mixture is heated to 200 to 400°C to react. In this case, it is desirable that the dihydric phenol and the dihalobenzenoid be used in substantially equal molar amounts, and that the excess amount of one of them should not exceed 5 mol%. The amount of alkali to be used in this case is selected such that the amount of alkali metal atoms is 0.3 to 2 gram atoms per mole of hydroxyl group. In this method, in addition to dihydric phenol and dihalobenzenoid as raw materials, if desired, halophenol of the general formula (), 4,4 '-Dichlorodiphenyl sulfone, 4,4'-dihydroxysidiphenylsulfone, etc. can also be used in combination. In this case, it is desirable to select a ratio such that the molar ratio of all hydroxyl groups to halogen atoms in the reaction system is within the range of 1:0.95 to 1:1.05. On the other hand, when the dihydric phenol of the general formula () is used in the form of an alkali salt, it is not necessary to particularly add an alkali to the reaction system. In this case, when halophenol of general formula () and 4,4'-dihydroxydiphenyl sulfone are used together, it is necessary to use these in the form of an alkali salt. Next, in an embodiment of the present invention using halfphenol of general formula (), a prescribed halfphenol and an alkali are added to the aromatic ketone compound of general formula () and heated, or an alkali salt of halophenol is added to the aromatic ketone compound of general formula () and heated. Add and heat. At this time, if halophenol is used, a small amount of divalent phenol or a dihalobenzenoid compound is added, and if an alkali metal salt of halophenol is used, a small amount of an alkali metal salt of divalent phenol or a dihalobenzenoid compound is added as desired. Benzenoid compounds can also be added as molecular weight regulators. however,
In either case, the molar ratio of hydroxyl group to halogen atom in the reaction system is 1:0.95 to 1:
It is desirable to add it within the range of 1.05. In any embodiment of the method of the present invention, the desired polymer can be obtained by heating at a temperature of 200 to 400°C for 5 minutes to 25 hours. If the reaction temperature is lower than 200°C, the produced polymer will precipitate with a low degree of polymerization, making it impossible to obtain the desired high molecular weight crystalline polymer, and if the reaction temperature is higher than 400°C, The use of temperature increases undesirable side reactions such as gelation. There is no particular restriction on the amount of the aromatic ketone compound represented by the general formula () used as a polymerization solvent in the method of the present invention, and a polymerization solvent commonly used in the production of conventional crystalline aromatic polyether ketones may be used. You can arbitrarily choose from a range of quantities. Usually, this range is from 1:0.8 to 1:5 by weight based on the total amount of raw materials. The crystalline aromatic polyetherketone thus obtained is a high polymer with a reduced viscosity of 0.6 or more, but it is difficult to form a film with a reduced viscosity of less than 0.6, or While film has the disadvantage of being weak and brittle, it exhibits various excellent properties. In the conventional production of aromatic polyetherketones, if a solvent with a ketone group or a thioether group such as benzophenone or dibenzothiophene is used, a product with a high molecular weight cannot be obtained; Although it was possible to obtain high molecular weight products only by using highly polar solvents such as sulfonic solvents (for example,
22938, Example 2), it was completely unexpected that a high molecular weight, highly crystalline aromatic polyetherketone was obtained using the solvent of the present invention having only a ketone group or a ketone group and an ether group. It was about that. This is thought to be because the structure of the solvent is similar to the structure of the produced polymer, so the produced polymer chains are well dispersed in the polymer and the reaction is likely to occur. Effects of the Invention The solvent used in the present invention has no oxidizing property as is clear from its structure, so there is no risk of oxidizing monomer phenols, and it is thermally stable itself and can be used repeatedly. In addition, it has the advantage that it is difficult to cause heterogeneous structures such as branching or coloration in the produced polymer. The high molecular weight, highly crystalline aromatic polyether ketone obtained by the method of the present invention has excellent heat resistance, chemical resistance, mechanical strength, etc., and can be used alone as structural materials, films, fibers, fibrils, and coating materials. It can also be used as a blend with other polymers, or as a composite material mixed with reinforcements or fillers such as glass fiber, carbon fiber, aramid fiber, calcium carbonate, calcium silicate, etc. . Examples Next, 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. Example 1 4.
4'-difluorobenzophenone 10.91g (0.05 mol), 4,4'-hydroxybenzophenone 10.71g
(0.05 mol), 7.19 g (0.052 mol) of potassium carbonate, and 40 g of isophthalophenone were added, and the atmosphere was replaced with nitrogen. The temperature was raised from room temperature to 300°C over a period of 1 hour under a nitrogen blanket while occasionally passing nitrogen through the mixture, and the mixture was then reacted at 300°C for 5 hours. Next, 4 g of dichlorodiphenyl sulfone was added to stabilize the terminals, and the resulting reaction product was cooled and pulverized in water, then washed twice with warm acetone, twice with hot water, and once with warm acetone. 19.2g white polymer powder
I got it. The yield was 98%, and the structure of the obtained polymer was

[Formula]. This polymer completely dissolves in concentrated sulfuric acid, and the reduced viscosity (ηsp/
C) is 0.80dl/g, DSC (heating rate (10℃/min)
The melting point determined was 367°C. In addition, after heat pressing this polymer at 400℃,
By rapid cooling, a pale yellow, durable film was obtained. Example 2 In Example 1, 4-fluoro-4'-hydroxybenzophenone was used instead of 4,4'-difluorobenzophenone (0.05 mol) and 4,4'-dihydroxybenzophenone (0.05 mol). 21.62g
19.6 g of white polymer powder was obtained in exactly the same manner as in Example 1, except for using (0.1 mol). Yield: 99% This polymer completely dissolves in concentrated sulfuric acid;
The ηsp/C at 25°C was 1.45 dl/g, and the melting point determined by DSC was 367°C. The structure of this polymer is

[Formula]. Example 3 The procedure was exactly as in Example 2, except that 40 g of 4,4'-dibenzoyl diphenyl ether was used instead of 40 g of isophthalophenone, and the reaction time at 300°C was changed to 7 hours. Similarly, white polymer
19.5g was obtained. Yield: 99% This polymer was completely dissolved in concentrated sulfuric acid, ηsp/C at 25°C was 1.20 dl/g, and the melting point determined by DSC was 367°C. Example 4 Example 2 except that 40 g of 4-benzoyl diphenyl ether was used instead of 40 g of isophthalophenone and the reaction time at 300°C was 8 hours.
In exactly the same manner as in Example 2, 18.9 g of a white polymer was obtained. Yield: 96% This polymer also completely dissolves in concentrated sulfuric acid;
The ηsp/C at 25°C was 0.63 dl/g, and the melting point determined by DSC was 366°C. Example 5 In Example 2, 0.1 mole of 4-fluoro-4'-hydroxybenzophenone was replaced with 4-chloro-
4′-Hydroxybenzophenone 23.27g (0.1mol)
Pale yellow polymer powder was prepared in exactly the same manner as in Example 2, except that the reaction time at 300°C was changed to 8 hours.
18.9g was obtained. Yield: 96% This polymer completely dissolves in concentrated sulfuric acid;
The ηsp/C at 25°C was 0.67 dl/g, and the melting point determined by DSC was 363°C. Example 6 4,4'-dihydroxybenzophenone 43.016g
(0.201 mol), 4N potassium hydroxide solution (f
= 1.0041) 100 ml and 100 ml of distilled water were placed in a 500 ml eggplant flask and stirred under nitrogen until uniformly dissolved. Next, water was distilled off using a rotary evaporator, and the yellow viscous liquid obtained was vacuum dried on a 160°C oil bath for 8 hours to obtain a yellow solid, which was then evaporated with nitrogen. Grinding in a box yielded 55 g of yellow powder. When a part of this powder was dissolved in distilled water and titrated with 0.1N hydrochloric acid using methylredo as an indicator, water was completely removed and it was found to be pure dipotassium salt of 4,4'-dihydroxybenzophenone. I found out. Next, 14.52 g of the dipotassium salt of 4,4'-dihydroxybenzophenone obtained in this way
(0.05 mol), 16.10 g (0.05 mol) of 4,4'-difluoroterephthalophein, and 40 g of isophthalophenone were placed in a 100 ml separable flask, and an experiment similar to Example 1 was conducted.
g was obtained. The structure of this polymer is It is. This product has ηsp/C at 25℃ in concentrated sulfuric acid.
It was 1.02 dl/g. No gel formation was observed in this polymer either. Example 7 In Example 1, 16.12 g (0.05 mol) of bis(4-fluorobenzoyl)benzene was added in place of 0.05 mol of 4,4'-difluorobenzophenone,
19.0 g of a white polymer powder was obtained in exactly the same manner as in Example 1, except that 5.506 g (0.05 mol) of hydroquinone was used instead of 0.05 mol of 4'-dihydroxybenzophenone. Yield: 97% This polymer was obtained at 25°C in concentrated sulfuric acid.
was 0.78 dl/g, and the melting point determined by DSC was 366°C. Also, no gel formation was observed in this polymer. The structure of this polymer is It is. Example 8 In place of 0.05 mol of 4,4'-dihydroxybenzophenone in Example 1, hydroquinone
Example 1 except that 5.506 g (0.05 mol) was used.
In exactly the same manner as above, 14.1 g of white polymer powder was obtained. Yield: 98% This polymer was prepared in concentrated sulfuric acid with ηsp/
C was 1.3 dl/g, and the melting point determined by DSC was 340°C. Also, no gel formation was observed in this polymer. The structure of this polymer is It is.

Claims (1)

[Scope of Claims] 1. In producing a crystalline aromatic polyether ketone by condensation polymerization of at least one aromatic dihydroxy compound component and at least one dihalogeno aromatic ketone component in a solvent,
As a solvent, the general formula (X in the formula is an oxygen atom or a ketone group, R, R',
R'' and R are each a hydrogen atom and have 1 to 3 carbon atoms
an alkyl group or phenyl group, which may be the same or different, and where one of m and n is 1 and the other is 0 or 1) A method for producing a crystalline aromatic polyether ketone having a reduced viscosity of 0.6 or more, the method comprising using a ketone compound. 2 In producing a crystalline aromatic polyether ketone by condensation polymerization of at least one monohydroxy monohalogeno aromatic ketone component in a solvent, as a solvent, the general formula (X in the formula is an oxygen atom or a ketone group, R, R',
R'' and R are each a hydrogen atom and have 1 to 3 carbon atoms
an alkyl group or phenyl group, which may be the same or different, and where one of m and n is 1 and the other is 0 or 1) A method for producing a crystalline aromatic polyether ketone having a reduced viscosity of 0.6 or more, the method comprising using a ketone compound.