JPS59164326A - Aromatic polyether-ketone copolymer - Google Patents

Abstract

PURPOSE:An aromatic polyether-ketone copolymer having good crystallinity and besides excellent processability, containing aromatic dihydroxy compound-derived structural units bonded in a specified manner of bonding. CONSTITUTION:An aromatic polyether-ketone copolymer (reduced viscosity of 0.2-2) wherein the structural unit of formula I (wherein R is H or a lower alkyl) is bonded at random to a structural unit of formula II (wherein n is 1-3) through a structural unit of formula III in such a manner than the structural units I and II are not adjacent to each other. The above copolymer is produced by cocondensing an alkali metal disalt of an aromatic dihydroxy compound of formula IV [e.g., bis(4-hydroxyphenyl)methane], with an alkali metal disalt of an aromatic dihydroxy compound of formula V (e.g., hydroquinone), and a 4,4'- dihalogenobenzophenone.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel aromatic polyetherketone copolymer.

Aromatic polyetherketone polymers are mostly crystalline polymers with high melting points (for example, T, E, A
t t wo o d et al. Am, chem, 8oc, P
olym, Pre-prints, 20(1), 191
(1979)).

These crystalline polymers have excellent mechanical properties and heat resistance, as well as good chemical resistance and electrical properties, so they are used for the insulation coating of electric wires and cables, and for the heat resistance and insulation parts of electrical parts. be done.

However, these aromatic polyetherketone polymers have a high melting point, and therefore have difficulties in processability, particularly in injection molding, extrusion molding, etc. Therefore, as an aromatic polyetherketone copolymer with a somewhat lower melting point, a terpolymer that already has an aromatic sulfone group (for example, R,
Viswanathan.

Others Am, Chem, Soc, Polym, Prepr
ints, 20(2) 365 (1979)) has been proposed. However, the range in which the polymer exhibits crystallinity is extremely narrow (and most of the polymers are immature), and the advantages of crystalline polymers (for example, they cannot be mixed with glass fiber or carbon fiber). By bending it to near the melting point of the polymer.
(no change in size) will no longer be available. Therefore, it is strongly desired to develop a practical aromatic polyetherketone polymer that maintains crystallinity and has good processability.

Against this background, the present inventors conducted various studies on aromatic polyetherketone copolymers, and found that
A copolymer of the present invention has been found that exhibits crystallinity over a wide temperature range.

That is, the present invention provides formulas (I), (TI) and ([II
)1 (wherein, R represents a hydrogen atom or a lower alkyl group.

is an integer from 1 to 3), and the structural units (I) and (n) are not adjacent to each other,
The reduced viscosity of any bonded via the structural unit (g) is 0.
It is an aromatic polyetherketone copolymer having a molecular weight of 2 to 2.0.

The copolymer of the present invention has the general formula 1 1 (in the formula, ■ (represents a hydrogen atom or a lower alkyl group))
It is obtained by copolymerizing an aromatic dihydroxy compound represented by the following formula with a general aromatic dihydroxy compound represented by 2) (where n is an integer of 1 to 3) with 4,4゛-dihalogeno or dinitrobenzophenone. be able to.

The aroma a and expressed by the general formula (5) used in this method
Examples of dihydroxy compounds include bis(4-hydroxyphenyl)methane, bis(4-hydroxyphenyl)ethane, 1.1-bis(4-hydroxyphenyl)propane, and 2.2-bis(4-hydroxyphenyl). Examples include furopane, 2,2-bis(4-hydroxyphenyl)bukun, and the like. and (preferably include bis(4-hydroxyphenyl)methane, bis(4-hydroxyphenyl)ethane, and 2,2-bis(4-hydroxyphenyl)propane.These may be used alone or in combination of two or more. and can be used.

Further, examples of the aromatic dihydroxy compound represented by the general formula (V) include compounds such as hydroquinone and 4,4-diphenol. Hydroquinone is particularly preferred.

Furthermore, as the 4,4-dihalogen or dinitrobenzophenone, 4,4-dichlorobenzophenone 7.4.
．． Examples include 4-difluorobenzophenone, 4-chloro-4-fluorobenzophenone, 4,4-dinitrohensiphenone, 4-chloro-4-nitrobenzophenone, and 4-fluoro-4-nitrobenzophenone. These can be used alone or as a mixture of two or more. Particularly preferred halogen compounds or nitro compounds include 4,4-dichlorobenzophenone, 4,4-difluorobenzophenone, or 4,4-dichlorobenzophenone.
Al with dinitrobenzophenone etc.

The amount of the above raw materials used is 0.7 to 1.3 molar ratio of 4,41-dilogeno or dinitrobenzophenone per 1 mole of aromatic dihydroxy compound in total, preferably 0.
．． The molar ratio is in the range of 85 to 1.15, and preferably around 1 molar ratio for the purpose of obtaining a high molecular weight copolymer.

The ratio of the aromatic dihydroxy compound represented by the general formula (■) to the aromatic dihydroxy compound represented by the general formula (V) is not particularly limited, but in order to take advantage of the advantages of the crystalline polymer, the ratio of the aromatic dihydroxy compound represented by the general formula (2) to the aromatic dihydroxy compound represented by the general formula (V) is V) 8:2 to 1:99
, preferably a molar ratio of 4:6 to 1:95.

By containing the compound of general formula (1) in the aromatic dihydroxy compound, the copolymer of the present invention exhibiting characteristic performance can be obtained.

The above-mentioned aromatic dihydroxy compound acts as a dialkali metal salt in the actual reaction.

Therefore, the dialkali metal salt of the aromatic dihydroxy compound may be prepared separately and used, or the salt may be formed before or simultaneously with the polymerization reaction to proceed with the reaction.

Types of alkali metals include lithium, sodium,
Examples include potassium and cesium, but particularly preferred is sodium or potassium. Examples of the metal compound used to form the alkali salt include hydroxides, carbonates, and hydrogen carbonates, with hydroxides and carbonates being particularly preferred.

%z.

A solvent is used in the copolymerization reaction as necessary.

The preferred solvent 7 is one that dissolves the raw material aromatic dihydroxy compound, 4,4''-di-logeno or di-trobenzophenone, and the produced polymer at high concentrations, and further dissolves the aromatic dihydroxy compound in a high concentration. Preferably, those that can also dissolve alkali salts or alkali metal compounds.

Therefore, as a suitable solvent, a polar solvent can usually be used. For example, dimethyl sulfoxide, sulfolane (tetramethyl sulfone) diphenyl sulfone, N, N
-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, dimethylsulfone,
Preferred solvents include diethyl sulfone and diethyl sulfoxide.

Furthermore, in addition to polar solvents, diphenyl ether, biphenyl, cuphenyl, phenanthrene, natutaleno,
Diphenylmethane, triphenylmethane, benzophenone, etc. can also be used.

The amount of these solvents used varies depending on the type of solvent, the type of aromatic dihydroquine compound, halogen compound or nitro compound used, and other reaction conditions, etc.
Usually, it is in the range of 0.605 to 20 times the weight of the aromatic dihydroxy compound, and more preferably in the range of 0.1 to 10 times by weight. In general, if the amount of solvent used is less than the -1- configuration range, no effect as a solvent will be recognized, and in particular, the reaction will not proceed further because the polymer formed in the traps will precipitate even if it has a low molecular weight. This makes it difficult to obtain a practical high molecular weight polymer.

On the other hand, if the amount of solvent is increased beyond the above range, the monomer concentration will decrease, so in order to increase the molecular weight, higher temperatures,
This may be undesirable as it requires a long reaction time.

Polymerization reactions can be carried out in various formats.

For example, in (1) a method using a separately prepared alkali metal salt of an anhydrous aromatic dihydroxy compound, the mixture is sufficiently uniformly mixed with 4,4-dihalogeno or 4,4-dinitrobenzophenone, and the mixture is heated with stirring to react. It is something that makes you At this time, the reaction is carried out without a solvent or in an appropriate solvent. (2) Next, the aromatic aromatic dihydroxy compound is reacted with an alkali metal compound, and Tsutsugi 4,41
-Dilogeno or 4,4-dinitrobenzophenone.

That is, an aqueous solution or a concentrated aqueous solution obtained by reacting an aromatic dihydroxy compound with an alkali metal compound is obtained, and then an azeotropic solvent is added to this aqueous solution to perform azeotropic distillation to remove the alkali of the aromatic dihydroxy compound produced. After the metal salt becomes substantially anhydrous, the temperature is raised to distill off the azeotropic solvent, and then the 4,4-dihalogeno or 4-dihalogeno
, 4-dinitrobenzophenone is added and reacted.

In this method as well, the reaction medium may not be added or one or more solvents may be used in any reaction step. (3) Furthermore, in the method of (2) above, 4,4-dihalogeno or 4,4-dinitrobenzophenone is added together with the azeotropic solvent, and while dehydration is performed by azeotropic distillation, the polymerization reaction is continued after completion of the dehydration. It is something.

In this method as well, it is possible to add no reaction medium or to use a solvent as a reaction medium in any reaction step. (
4) Furthermore, as another method, a mixture of an aromatic dihydroxy compound, 4,41-dilogeno or 4,4'-dinitrobenzophenone and an alkali metal carbonate or hydrogen carbonate is heated in the presence of a solvent. The polymerization reaction is carried out while expelling the produced water and carbon dioxide gas with an inert gas.

(5) Furthermore, in the method of (4), an azeotropic solvent is added and heated to allow the polymerization reaction to proceed simultaneously with the production of an alkali metal salt of the aromatic dihydroxy compound and the removal of the produced water by azeotropic distillation.

Among these various methods, the optimum method is selected depending on the reactivity, physical properties, etc. of the aromatic dihydroxy compound and 4,4-dihalogeno or 4,4-dinitrobenzophenone.

In the above method, examples of azeotropic solvents used to remove water from the reaction system by azeotropic distillation include aromatic hydrocarbons such as benzene, toluene, and quincylene, chlorobenzene, O-dichlorobenzene, and the like. Examples include halogenated aromatic hydrocarbons, but any other solvent that is inert to the reaction and forms an azeotrope with water can be used.

The amount of these azeotropic solvents to be used can be determined based on the amount of water present in the reaction system, the azeotropic composition, etc.

In dehydration using an azeotropic solvent, for example, water is distilled out together with the azeotropic solvent, the distillate is cooled and condensed, the water and the azeotropic solvent are separated into two layers, and the separated azeotropic solvent If the layer is allowed to reflux into the reaction system, the azeotropic solvent is effectively used, so that dehydration can be completed without using a large excess of the azeotropic solvent.

The time required for azeotropic dehydration also depends on the amount of water present in the reaction system,
Although it varies depending on the type and amount of the azeotropic solvent used, from a practical point of view it is preferable to complete the process within 10 hours, and more preferably within 5 hours.

The temperature of the polymerization reaction varies depending on the type of reaction raw material components, the ratio of reaction raw material components, the type of solvent, the type of polymerization reaction, etc., but is usually in the range of 40 to 450 °C, preferably 60 to 400 °C. Implemented within the scope of ≠. If the reaction temperature is lower than 0°C, it will take a long time to obtain a polymer with the desired molecular weight, which is impractical. On the other hand, if the temperature exceeds 1〆0℃, the side reactions of the desired polymerization reaction (di, The temperature may be changed gradually or stepwise depending on the progress of the reaction.

Such a change in reaction temperature is caused by a change in the proportion of aromatic dihydroxy compound used, i.e., the general formula 〇■)
As the proportion of aromatic dihydroxy compounds increases, lower temperatures may be possible.

The time required for the reaction varies widely depending on the type of reaction raw material components, the ratio of 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, preferably 30 minutes. It is carried out for a period of ~24 hours.

The reaction atmosphere in which the reaction is carried out is preferably free of oxygen, and good results are obtained when the reaction is carried out in nitrogen or other inert gas. Aromatic dihydroxy/compounds of general formula (V), especially alkali salts of hydroquinone, are easily oxidized by oxygen, and heating further accelerates the oxidation, hindering the desired polymerization reaction and making it difficult to increase the molecular weight. In addition to this, it also causes coloration of the polymer, so it is desirable to perform the reaction in an inert gas atmosphere.

The polymerization reaction can usually be stopped by cooling 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, if necessary. Examples of such compounds include methyl chloride, ethyl chloride, 4-1'lorbenzophenone,
4-fluorobenzophenone, P-chlornitrobenzene, 4,4-dichlorodiphenylsulfone, bis(4-
(fluorophenyl) ketone, etc.

Furthermore, when the polymerization reaction is stopped and the reactants are cooled to room temperature, the viscosity of the reactants increases significantly. Since solidification may occur, in such cases it is effective to dilute with an inert solvent before or during cooling. The solvent for such dilution is preferably one in which the alkali halide produced is insoluble.
Such solvents are also advantageous in the separation of polymers. When a solvent is used in the polymerization reaction, if a suitable diluting solvent is not available, it must be further diluted with the same solvent used in the reaction, or cooled and solidified, and then finely divided using a grinder such as a Waring blender. It may be shaped.

For separation and purification of the polymer after completion of the polymerization reaction, known methods for aromatic polyether polymers can be employed. For example, by adding a solvent such as chlorobenzene, sym-te, or chloroethane into the reaction mixture, the salt (alkali halide) that precipitates is added to the reaction mixture. After separation or separation of the salt, the solution or reaction mixture as it is is usually added to the nonsolvent of the polymer, or conversely, the nonsolvent of the polymer is added to the polymer solution. By this method, the desired polymer can be precipitated.

As a non-solvent for the polymer, for example, methanol, ethanol, isopropanol, acetone, methyl ethyl ketone, water, etc. are often used. These may be used alone or as a mixture of two or more.

The precipitated polymer is washed using the above-mentioned non-solvent, and the resulting polymer is heated and dried under normal pressure or reduced pressure to form a polymer that can be used in various processing methods, such as powder, flake, or thin film. can be obtained in various forms depending on the precipitation method.

In the aromatic polyetherketone copolymer of the present invention obtained by polymerization as described above, the structural unit represented by the formula (I) and the structural unit represented by the formula (■) are not adjacent to each other, They are bonded via a structural unit represented by the formula GJD.

Formula (II) bonded via the structural unit of the formula ([D), (
The arrangement of the structural units in [[) is not necessarily one in which they are combined in an alternating and regular manner, and the arrangement is arbitrary. That is, they can be bonded alternately, randomly, or in a block form via the structural units of formula (III).

The copolymers of the present invention have structural units of formula (I) together with structural units of formula (11), and formula (GrI), and have a calculated value of The viscosity is 0.2 to 2.0.

These characteristics give the copolymer of the present invention unique performance, making it possible to lower the melting point in a wide temperature range while maintaining the crystallinity of the polymer (for example, the copolymer of the general formula (IV '
) is 2,2-bis(4-hydroxyphenyl)
Propane, when the compound of general formula (V) is hydroquinone, has a melting point range of 240°C to 337°C. ) has greatly improved processability and has made it possible to provide composite materials that are mixed with a wide range of polymer groups and glass fibers and/or carbon fibers to suit multiple applications.

The copolymer obtained by the present invention can be molded into a desired product using conventional molding methods and conditions. That is, compression molding, extrusion molding, and injection molding can be carried out within the capabilities of general molding machines, and the desired product can be obtained in a desired state.

The molding temperature for extrusion or injection molding of the copolymer of the present invention is 200 to 400°C, preferably 250 to 380°C.
/y! Within the range of This compound was synthesized from only bis(4-fluorophenyl)ketone and hydroquinone, making it possible to process step 2.

In addition, there are no restrictions on the size, shape, etc. of the molded product (in addition to regular molded products, films, sheet-like products, parts with precise microstructures, etc. can be easily molded using general molding methods.

When molding the copolymer of the present invention, a filler component may be included depending on the intended use. Typical examples of filler components include glass fiber, carbon fiber, aromatic polyamide fiber, carbon, magnesium oxide, cal/lamb oxide, calcium stearate, molybdenum sulfide, talc, alumina, silica, asbestos, etc. It can be used alone or as a mixture of two or more types. Among these fillers, fibrous fillers are particularly preferred in order to maintain mechanical properties during heating. The use l of these fillers is 0.5 based on the weight of the copolymer of the invention.
~150%, preferably 3-120%.

Furthermore, antistatic agents, colorants, flame retardants, lubricants, processing improvers, stabilizers, etc. that are usually added during resin processing can also be added singly or as a mixture of two or more.

The amount added is 10 to 10% based on the weight of the copolymer of the present invention.
60 parts, preferably in the range of 10 to 40 parts.

The copolymer of the present invention can also be produced into a film from an organic solvent solution by a casting method, and like an extruded film, a transparent/or opaque, tough, and highly heat resistant product can be obtained.

The copolymer of the present invention can be used in a wide range of fields such as various electrical and electronic parts, housings, automobile parts, aircraft interior materials, sliding parts, gears, insulating materials, medical materials, and steam sterilization containers. be able to.

Examples and comparative examples are shown below.

In addition, the converted viscosity in the examples? tre d is 25°C
When the solvent is chloroform, a solution of 0.2 g of polymer dissolved in 1.00 m of chloroform is used, and when the solvent is sulfuric acid, 0.1 g of polymer is dissolved in ioomz of sulfuric acid. The values were measured using a viscometer and calculated using the following formula.

Here, to - Outflow time of pure solvent 1, - Outflow time of polymer solution C = Polymer concentration in polymer solution (g/d I) As the solvent, chloroform or sulfuric acid was used as appropriate depending on the composition of the polymer. .

Example 1 Flask K, 300-nu, equipped with stirrer, thermometer, condenser and distillate separator, dropping funnel and nitrogen inlet tube, 2.2-bis(4-hydroxyphenyl)propane 13. 68 g (0.06 mol), hydroquinone 1
．． 65 +7 (0,015 mol), chlorobenzene 75-1 in which oxygen was removed by blowing nitrogen in. Dimethyl sulfoxide 6Q treated in the same manner as Q 71I7! The reaction system was completely replaced with nitrogen by introducing nitrogen gas into the solution while stirring. From the dropping funnel 4.4. ．． 8% potassium hydroxide aqueous solution], 9.69 was added dropwise over 10 minutes, and further 5 d
The inside of the dropping funnel was washed with pure water and added to the reaction solution.

The liquid crystal was heated to 60° C. and heated until flow selection started. When the water in the reaction system is removed azeotropically with chlorobenzene and the chlorobenzene layer is returned to the reaction system while continuing azeotropic dehydration, the internal temperature rises from around 120'C to around 140°C, and then reaches 145°C. Distillation of water is no longer permitted in the vicinity. Heating was continued to distill off most of the chlorobenzene, yielding a white slurry. anti) The temperature of the core liquid is 10
Cool to around 0° and 4,4-difluorobenzophenone 16.35! When 7 (0,075 mol) was added, the temperature of the reaction solution rose to 135°C. The reaction was allowed to proceed at that temperature for 6 hours. After the reaction was completed, the reaction solution was poured into methanol being stirred with a homomixer to precipitate a copolymer, which was further washed with water and dried to obtain 36.69 of a white copolymer.

The obtained copolymer was subjected to elemental analysis and 'H-NMR measurements. The measurement results were as follows.

calculation value stop) 8],,06. 5.32 analysis value excellent)
81.01 5.27'H-NMR The copolymer was dissolved using deuterated chloroform and 10
Measured using a 0 MHz H-NM device.

δ-1,70(s,f(3),7,01(d,H
); J+, h-9Hz, 7.04 (d j-death)
:”-+5=9Hz, 7.28 (s, H
'), 7.29(d, +(2); J!, + 1-
9Hz, 7.80(d, f('); given 4=9Hz
Proton intensity ratio Hl:W:G:I:H':H6-4:4:6:5:5:
] From these results, the obtained copolymer has the following structural units (1), (ii) and (iii) (the numbers attached to the hydrogen atoms in the formula are the same as the numbers of the protons) (i) : (Ii) : (1) = 4:1:5 composition ratio, which was confirmed to be the same as the raw material usage ratio.

In addition, the copolymer in chloroform (0,217/10
0i) Converted viscosity measured at 25°C], , 94. (
It was 1+//g.

Example 2 The molar ratio of 2.2-his(4-hydroxyphenyl)propane and hydroquinone was 6:4, diphenylsulfone was used instead of dimethylsulfoxide as the heating medium, and the reaction temperature was 1 to 320'C. The reaction was carried out in the same manner as in Example 1 except for this.

The calculated viscosity of the obtained copolymer was sulfuric acid (0,19-/10
It was measured at 25°C in (W) and found to be 0.21.

Practical Example 3 Into a 300-cm flask equipped with a stirrer, thermometer, condenser, dropping funnel, and nitrogen inlet tube, 10.62 q (0,0
45 moles), hydroquinone 11.55!7! (0,1
05 mol), 4,4-difluorobenzophenone 32.
739 (0.1.5 mol) was taken, the reaction system was replaced with nitrogen, and then heated to 180°C while passing nitrogen gas.

Add 99.5% potassium carbonate 7.079 and 200'C
Warm to 250°C and hold for 30 minutes, then heat to 250°C 3
The temperature was maintained for 0 minutes, and the temperature was further heated to 320°C, and the reaction was allowed to proceed for 2 hours.

The reaction solution was transferred to a beaker and cooled to solidify. This material was pulverized using a pulverizer, washed four times with acetone and water, and dried. The resulting pale gray polymer had a reduced viscosity of 25° in sulfuric acid (0.19/100d).
It was measured at 0.25 dl//L;

Example 4 2,2-bis(
・1-hydroquinphenyl) furopane 17,1.0 so(
0,075 mol), hydroquinone 8.26 (0,07 mol)
5 mole), 4,4-difluorobenzophenone 32,7
After replacing the reaction system with nitrogen, add 7.07 g of 99.5% potassium carbonate, add 10 ml of chlorobenzene from which oxygen has been removed by blowing in nitrogen, and heat while passing nitrogen gas. did. Chlorobenzene begins to reflux around 140°C, and the produced water gradually accumulates in the separator.

This aqueous layer was separated, and the chlorobenzene layer was added to the reaction system. After that, the distilled chlorobenzene layer was extracted so that the reaction temperature was 200°C, and the chlorobenzene from which oxygen had been removed was added dropwise from the dropping funnel.
The mixture was allowed to react for an hour, then the temperature was raised to 250°C, and the reaction was made for 30 minutes, and the temperature was further raised to 320°C, and the reaction was made for 1 hour. The subsequent operations were the same as in Example 3. The resulting copolymer had a reduced viscosity of 0.21 when measured in sulfuric acid (0.1!7/100 m/) at 25°C.

Ritsu, Martyr I 4.4 instead of 4.4'-difluorobenzophenone
'-dichlorobenzophenone 18,83 was used, K
Sulfolane was used instead of dimethyl sulfoxide, and the reaction temperature was changed to 200'C instead of 135°C.
The reaction was carried out in the same manner as in Example 1, except that . The calculated viscosity of the obtained copolymer was chloroform (0.27/
], 0640 measured at 25°C in OO, d)
It was dishio.

Examples 6 to 7 The molar ratio of the reactants of 2.2-bis(4-hydroxyphenyl) furo/kun and hydroquinone was changed as shown in Table 1, and the mixture was overlaid.

The reduced viscosity of the obtained copolymer is shown in Table 1.

Table 1 Example 8 17.10 g (0,075 mol) of 2,2-bis(4-hydroxyphenyl)propane in the method of Example 4
Bis(4-hydroquinphenyl)methane instead1.
Example 4 except that 5.00 mol (0,075 mol) was used.
The reaction was carried out in the same manner.

The calculated viscosity of the obtained copolymer was sulfuric acid (0,1!7710
0? Measured at 25°C in I+7 temperature, 0.25
dl/9, and the X-ray spectrum of this copolymer confirmed that it had crystallinity.

Comparative Example 1 Polymerization was carried out in the same manner as in Example 3, using hydroquinone instead of 2,2-bis(4-hydroxyphenyl)propane (that is, using only hydroquinone as the aromatic dihydroxy compound). The resulting light gray polymer was dissolved in sulfuric acid (0,1!7/1007 nl!) at 25
It had a reduced viscosity of 1.88 dl/9, measured at °C. This polymer powder was made into a sheet by the method of Test Example 1 described later, and the glass transition temperature (T g
), the melting point (Tm) was measured, and Tg, 140°C,
, Tm 34.0'C was obtained.

This polymer naturally had only one melting point (Tm) L.

Test Example 1 The copolymer powders obtained in Examples 1 to 7 were heated at 380°C.
, 100 kg/mλ for 5 minutes to produce a pressed sheet with a thickness of 0.25 ii.

In each case, strong sheets were obtained.

When the reduced viscosity of each of these sheets was measured using the method shown in the examples above, no difference was found between the sheets and the powder.

This revealed that reactions such as crosslinking and reticulation did not proceed during hot press molding, and that the polymer could be stably processed. Therefore, it can be seen that melt processing such as extrusion and injection is possible.

Test Example 2 As a result of measuring the sheet obtained in Test Example 1 with a DSC (differential calorimeter), the glass transition temperature (Tg) and melting point (Tm
) were as shown in Table 2.

Claims (1)

[Claims] 1) Represented by the formulas (I), (II) and (2)-(wherein, R represents a hydrogen atom or a lower alkyl group. n is an integer from 1 to 3) An aromatic polyether ketone having a reduced viscosity of 0.2 to 2.0, in which the structural units (I) and (II) are not adjacent to each other and are arbitrarily bonded via the structural unit GII). The copolymer according to claim 1, wherein the structural unit of formula (1) is 104Σ〇-.