Polyether ether ketone compound and method for producing the same

Abstract

To provide a polyether ether ketone compound that offers easy synthesis and excellent processability, produces a resin composition containing the same with excellent dielectric characteristics (low relative dielectric constant and low dielectric loss tangent), and exhibits high heat resistance and low moisture absorption.SOLUTION: The present invention provides a polyether ether ketone compound represented by formula (1). In formula (1), R1 and R2 independently represent a substituted or unsubstituted aromatic group, R' independently represents a hydrogen atom, a C1-6 alkyl group or a halogen atom, A1 and A2 independently represent a single bond or a C1-4 alkylene group, and n represents a number of 1-100.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a polyether ether ketone compound and a method for producing the same. [Background technology]

[0002] In recent years, with the increase in the amount of information and communication, the next-generation communication system known as 5G has come into use, and information and communication in the high-frequency band (millimeter wave region of 26 GHz to 80 GHz) has become more common. Higher performance is also required in electronic devices, and the insulating materials used are required to have even lower relative dielectric constants and lower dielectric loss tangents.

[0003] As insulating materials, epoxy resin compositions containing epoxy resin, a specific phenol-based hardener, phenoxy resin, rubber particles, polyvinyl acetal resin, etc., as shown in Patent Documents 1 and 2, are known, but it has become clear that these materials are not satisfactory for high-frequency band applications, such as those represented by the keyword 5G. In contrast, Patent Document 3 reports that an epoxy resin composition containing an epoxy resin, an active ester compound, and a triazine-containing cresol novolac resin is effective in lowering the dielectric tangent, but even this material needs to have a lower dielectric constant for high-frequency applications.

[0004] On the other hand, Patent Document 4 reports that a resin film made of a resin composition containing a bismaleimide resin having a long-chain alkyl group as a non-epoxy material and a curing agent has excellent dielectric properties, but since this is essentially a combination of a bismaleimide resin having a long-chain alkyl group and a hard low-molecular aromatic maleimide, it is very difficult to achieve the high glass transition temperature (Tg) of 100°C or more required for substrate applications. In addition, bismaleimide resins having long-chain alkyl groups have the problem of a large coefficient of thermal expansion (CTE).

[0005] In addition, the use of super engineering plastics that have excellent heat resistance, mechanical strength, and low dielectric properties has also attracted attention, and substrates using liquid crystal polymers (LCP), polytetrafluoroethylene (PTFE), polyether ether ketone (PEEK), polyetherimide (PEI), and the like have been proposed (Patent Document 5). However, when using super engineering plastics, there are often problems with processability. For example, PEEK has excellent heat resistance, a continuous use temperature of 260°C, and excellent dielectric properties, but it has a high melting point of over 300°C and poor solubility in solvents, making it difficult to mold.

[0006] Non-Patent Document 1 shows an example in which a maleimide group is introduced to the end of PEEK having a certain molecular weight to impart thermosetting properties. It has also been reported that a composition using this can be made into a varnish and molded, and has excellent dielectric properties (Patent Document 6). [Prior art documents] [Patent documents]

[0007] [Patent Document 1] JP 2007-254709 A [Patent Document 2] JP 2007-254710 A [Patent Document 3] JP 2011-132507 A [Patent Document 4] International Publication No. 2016 / 114287 [Patent Document 5] Patent No. 5958558 [Patent Document 6] Patent Publication No. 2022-25704 [Non-patent literature]

[0008] [Non-Patent Document 1] JLHedrick et al., “Elastomeric behavior of crosslinked poly(aryl ether ketone)s at elevated temperatures”, Polymer, 1992, Vol. 33, p. 5094-5097 Summary of the Invention [Problem to be solved by the invention]

[0009] However, the production of a polyether ether ketone compound having a maleimide group described in Patent Document 6 involves a process in which difluorobenzophenone is reacted with a diol to synthesize a main chain, and then aminophenol is further reacted to convert the terminal into an amine, followed by maleimide formation. This process requires many steps and takes a long reaction time. Therefore, an object of the present invention is to provide a polyether ether ketone compound which is easy to synthesize, has excellent processability, excellent dielectric properties (low relative dielectric constant and low dielectric tangent), high heat resistance, and low moisture absorption. [Means for solving the problem]

[0010] Means for Solving the Problems The present inventors have conducted extensive research to solve the above problems and have found that the following polyether ether ketone compound can achieve the above object, thereby completing the present invention.

[0011] That is, the present invention provides the following polyether ether ketone compound and a method for producing the same. <1> A polyether ether ketone compound represented by the following formula (1): [ka] (In formula (1), R 1 and R 2 each independently represents a substituted or unsubstituted aromatic group; each R' independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a halogen atom; A 1 and A 2each independently represents a single bond or an alkylene group having 1 to 4 carbon atoms, and n is a number from 1 to 100. <2> In formula (1), R 1 and R 2 are each independently a group having an aromatic structure having 6 to 30 carbon atoms. <1> The polyether ether ketone compound described above. <3> The polyether ether ketone compound represented by formula (1) has a number average molecular weight of 700 to 50,000. <1> or <2> The polyether ether ketone compound according to claim 1. <4> 4,4'-difluorobenzophenone, The following formula (2) [ka] (In formula (2), R represents a substituted or unsubstituted aromatic group.) A compound represented by the formula: in the presence of an alkali metal carbonate to obtain a polyether ether ketone compound having hydroxyl groups at both ends; and the polyether ether ketone compound having hydroxyl groups at both ends obtained in step A; The following formula (3) [ka] (In formula (3), X represents a chlorine atom, a bromine atom, or an iodine atom; R' each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a halogen atom; and A represents a single bond or an alkylene group having 1 to 4 carbon atoms.) A compound represented by the formula: Step B: reacting in the presence of a base; or the polyether ether ketone compound having hydroxyl groups at both ends obtained in step A; 2,3,4,5,6-pentafluorostyrene, in the presence of an alkali metal carbonate. have <1> ~ <3> 13. A method for producing the polyether ether ketone compound according to claim 12. <5> In step A, 4,4'-difluorobenzophenone is reacted with the compound represented by formula (2) in a molar ratio of 4,4'-difluorobenzophenone / compound represented by formula (2)=1 / 1.0 to 2.0. <4> A method for producing the polyether ether ketone compound described in claim 1. Effect of the Invention

[0012] The polyether ether ketone compound of the present invention can be synthesized relatively easily with a small number of steps and has excellent processability. In addition, a resin composition containing the compound has excellent dielectric properties (low relative dielectric constant, low dielectric tangent), high heat resistance, and low moisture absorption. Therefore, the polyether ether ketone compound of the present invention is useful as an insulating material for electronic devices used in high frequency bands. [Brief description of the drawings]

[0013] [Figure 1] 1 is a 1H-NMR spectrum of a polyether ether ketone compound having hydroxyl groups at both ends synthesized in Example 1. [Diagram 2] 1 is an FT-IR spectrum of a polyether ether ketone compound having hydroxyl groups at both ends, synthesized in Example 1. [Diagram 3] 1 is a 1H-NMR spectrum of the polyether ether ketone compound having fluorostyryl groups at both ends synthesized in Example 1. [Figure 4] 1 is an FT-IR spectrum of a polyether ether ketone compound having fluorostyryl groups at both ends, synthesized in Example 1. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] The present invention will be described in detail below. Polyether ether ketone compounds The polyether ether ketone compound of the present invention is represented by the following formula (1).

[0015] [ka]

[0016] In formula (1), R 1 and R 2 each independently represents a substituted or unsubstituted aromatic group; each R' independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a halogen atom; A 1 and A 2 each independently represents a single bond or an alkylene group having 1 to 4 carbon atoms, and n is a number from 1 to 100.

[0017] In formula (1), R 1 and R 2 The substituted or unsubstituted aromatic group represented by the formula (I) is preferably a group having an aromatic structure with 6 to 30 carbon atoms, and more preferably a group having an aromatic structure with 10 to 25 carbon atoms. 1 and R 2 may be different or the same. 1 and R 2 The structures of the following are shown as examples, however, they are representative examples and are not limited to these. [ka] [ka] [ka] [ka] (In the above formula, * means a bond with the oxygen atom in formula (1).)

[0018] Among these, R in formula (1) 1 and R 2 As the aromatic group represented by the formula: [ka]

[0019] In formula (1), R' is independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a halogen atom. Examples of the alkyl group having 1 to 6 carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, and a hexyl group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. In the starting compounds in the production method described below, it is preferable that all of R' are hydrogen atoms or all of R' are fluorine atoms.

[0020] In formula (1), A 1 and A 2 A is a single bond or an alkylene group having 1 to 4 carbon atoms. Examples of the alkylene group having 1 to 4 carbon atoms include a methylene group, an ethylene group, a trimethylene group, and a tetramethylene group. 1 and A 2 is preferably a single bond or a methylene group.

[0021] In formula (1), n ​​is a number from 1 to 100, and preferably a number from 5 to 60. If n exceeds 100, the resulting polyether ether ketone compound will have an excessively high melting point or poor solvent solubility, which is not preferable.

[0022] The number average molecular weight (Mn) of the polyether ether ketone compound is not particularly limited, but is preferably from 700 to 50000, more preferably from 1500 to 40000, and further preferably from 3000 to 35000. Within this range, the polyether ether ketone compound of the present invention has a good melting point and solvent solubility, and has improved moldability.

[0023] The number average molecular weight (Mn) referred to in this specification is the number average molecular weight measured by GPC under the following conditions using polystyrene as the standard substance. [GPC measurement conditions] Developing solvent: Tetrahydrofuran (THF) Flow rate: 0.35mL / min Detector: Refractive index detector (RI) Column: TSK Guardcolumn SuperH-L TSKgel SuperHZ4000(4.6mmI.D.×15cm×1) TSKgel SuperHZ3000(4.6mmI.D.×15cm×1) TSKgel SuperHZ2000 (4.6mmI.D.×15cm×2) (All manufactured by Tosoh Corporation) Column temperature: 40℃ Sample injection volume: 5 μL (0.2% by mass in THF solution)

[0024] Method for producing polyether ether ketone compound The method for synthesizing the polyether ether ketone compound of the present invention is not particularly limited, but for example, the compound can be efficiently produced by the method shown below.

[0025] 4,4'-difluorobenzophenone, The following formula (2) [ka] (In formula (2), R represents a substituted or unsubstituted aromatic group.) A compound represented by the formula: in the presence of an alkali metal carbonate to obtain a polyether ether ketone compound having hydroxyl groups at both ends; and the polyether ether ketone compound having hydroxyl groups at both ends obtained in step A; The following formula (3) [ka] (In formula (3), X represents a chlorine atom, a bromine atom, or an iodine atom; R' each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a halogen atom; and A represents a single bond or an alkylene group having 1 to 4 carbon atoms.) A compound represented by the formula: Step B: reacting in the presence of a base; or the polyether ether ketone compound having hydroxyl groups at both ends obtained in step A; 2,3,4,5,6-pentafluorostyrene, in the presence of an alkali metal carbonate. The present invention relates to a method for producing a polyether ether ketone compound having the formula:

[0026] In the above-mentioned production method, each step can be roughly divided into synthesis of a polyether ether ketone main chain and modification of its terminals. The details will be described below.

[0027] In step A, for example, aromatic nucleophilic substitution polymerization of 4,4'-difluorobenzophenone with a specific aromatic diol represented by formula (2) can be used. This reaction generally proceeds in an organic solvent (e.g., non-polar solvent, high boiling point aprotic polar solvent, etc.) in the presence of an alkali metal carbonate by heating at 130 to 140°C and further heating to 170 to 180°C.

[0028] In formula (2), R is R in formula (1) 1 and R 2 Examples of the compound represented by formula (2) include the same groups as those exemplified in the above. As the compound represented by formula (2), 1,3-dihydroxybenzene, 2,2-bis(4-hydroxyphenyl)propane, 1,3-bis[2-(4-hydroxyphenyl)-2-propyl]benzene, and 1,4-bis[2-(4-hydroxyphenyl)-2-propyl]benzene are preferred.

[0029] The alkali metal carbonate is not particularly limited, but examples thereof include lithium carbonate, sodium carbonate, potassium carbonate, rubidium carbonate, and cesium carbonate.

[0030] Examples of the organic solvent include toluene, xylene, anisole, N-methyl-2-pyrrolidone (NMP), N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), etc. These may be used alone or in combination of two or more.

[0031] The molar ratio of 4,4'-difluorobenzophenone to the specific aromatic diol, 4,4'-difluorobenzophenone / aromatic diol, is preferably 1 / 1.01 to 2.0, more preferably 1 / 1.02 to 1.80, and even more preferably 1 / 1.03 to 1.50. By mixing 4,4'-difluorobenzophenone and a specific aromatic diol in this ratio, it is possible to synthesize polyether ether ketone having hydroxyl groups at both ends.

[0032] After step A, purification may be performed by any known method. Examples of the purification method include a method in which water is added to the mixture after step A, and the mixture is stirred and allowed to stand to separate the organic solvent from the aqueous solution, and a method in which the mixture after step A is poured into a poor solvent to recover the precipitate and then washed with water. The compound obtained in step A may be extracted as a varnish of the organic solvent used in step A, or it may be extracted as a solid by pouring the mixture into a poor solvent and recovering the precipitate. By the above-mentioned step A, a polyether ether ketone compound having hydroxyl groups at both ends can be obtained.

[0033] After step A, the hydroxyl groups at both ends of the polyether ether ketone compound having hydroxyl groups at both ends obtained in step A are modified in step B or B'.

[0034] In step B, the polyether ether ketone having hydroxyl groups at both ends obtained in step A is reacted with a compound represented by the following formula (3): [ka] (In formula (3), X represents a chlorine atom, a bromine atom, or an iodine atom; R' each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a halogen atom; and A represents a single bond or an alkylene group having 1 to 4 carbon atoms.) The reaction conditions for step B are not particularly limited, but an example thereof includes a method in which the polyether ether ketone compound having hydroxyl groups at both ends obtained in step A is reacted with the compound represented by formula (3) in the presence of a base in a mixed solvent of an organic solvent and water at 60°C to 100°C.

[0035] In formula (3), the alkyl group having 1 to 6 carbon atoms represented by R' includes methyl, ethyl, propyl, butyl, pentyl and hexyl groups, similar to the alkyl group having 1 to 6 carbon atoms represented by R' in formula (1), and the halogen atom includes fluorine, chlorine, bromine and iodine atoms, similar to the halogen atom represented by R' in formula (1). R' in formula (3) corresponds to R' in formula (1) which is the product, and is preferably a hydrogen atom. In the formula (3), the alkylene group having 1 to 4 carbon atoms represented by A is the same as A in the formula (1). 1 and A 2 As in the above, examples of the A in formula (3) include a methylene group, an ethylene group, a trimethylene group, and a tetramethylene group. 1 and A 2 and is preferably a methylene group. The positional relationship between the vinyl group and the group represented by "-AX" in the compound represented by formula (3) is not particularly limited, and examples of the compound represented by formula (3) include p-vinylbenzyl halide, m-vinylbenzyl halide, and a mixture thereof. More specific examples include p-vinylbenzyl chloride, m-vinylbenzyl chloride, a mixture of p-vinylbenzyl chloride and m-vinylbenzyl chloride, p-vinylbenzyl bromide, m-vinylbenzyl bromide, a mixture of p-vinylbenzyl bromide and m-vinylbenzyl bromide, p-vinylbenzyl iodide, m-vinylbenzyl iodide, a mixture of p-vinylbenzyl iodide and m-vinylbenzyl iodide, and the like. The composition ratio of the mixture of the p-vinylbenzyl halide and the m-vinylbenzyl halide is not particularly limited, but the molar ratio of p-isomer / m-isomer is preferably 90 / 10 to 10 / 90, more preferably 75 / 25 to 25 / 75, and even more preferably 60 / 40 to 40 / 60.

[0036] Bases include, for example, alkali metal hydroxides such as sodium hydroxide, potassium hydroxide, and mixtures thereof. The alkali metal hydroxide preferably has a hydroxyl group / alkali metal hydroxide ratio of 1 / 1.1 to 15, more preferably 1 / 1.5 to 10, and even more preferably 1 / 2 to 5, in the polyether ether ketone compound having hydroxyl groups at both ends obtained in step A.

[0037] In step B, a phase transfer catalyst can also be used to improve the reaction rate. Examples of the phase transfer catalyst include quaternary ammonium compounds. Specific examples include tetramethylammonium chloride, tetraethylammonium bromide, tetrabutylammonium bromide, benzyltriethylammonium chloride, and benzyltriethylammonium bromide. In terms of promoting the reaction, the phase transfer catalyst is preferably added in an amount of 0.1 to 1% by mass to the polyether ether ketone compound having hydroxyl groups at both ends obtained in step A.

[0038] Examples of the organic solvent used in step B include toluene, xylene, anisole, N-methyl-2-pyrrolidone (NMP), N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), etc. These may be used alone or in combination of two or more.

[0039] A polyether ether ketone compound represented by the above formula (1) is obtained by step B. The polyether ether ketone compound represented by formula (1) may be used for a desired application as it is in the form of a varnish of the organic solvent used in step B, or may be purified and isolated after step B by any known method, for example, by reprecipitation by adding a poor solvent to the mixture after step B, and used for a desired application as a solid powder.

[0040] In step B', an aromatic nucleophilic substitution reaction between the polyether ether ketone compound having hydroxyl groups at both ends obtained in step A and 2,3,4,5,6-pentafluorostyrene can be used. The reaction between the hydroxyl group and 2,3,4,5,6-pentafluorostyrene in step B' can be described, for example, in Liquid Crystals, 2021, Vol. 48 (5), p. 672-688, and the reaction proceeds in an organic solvent (e.g., a nonpolar solvent or a high-boiling aprotic polar solvent) in the presence of an alkali metal carbonate at 40 to 50 ° C.

[0041] Examples of the organic solvent include toluene, xylene, anisole, N-methyl-2-pyrrolidone (NMP), N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), etc. These may be used alone or in combination of two or more.

[0042] The alkali metal carbonate is not particularly limited, but examples thereof include lithium carbonate, sodium carbonate, potassium carbonate, cesium carbonate, and lithium carbonate.

[0043] The molar ratio of the polyether ether ketone compound having hydroxyl groups at both ends to 2,3,4,5,6-pentafluorostyrene is preferably hydroxyl groups of the polyether ether ketone compound / 2,3,4,5,6-pentafluorostyrene=1 / 1.1 to 10, more preferably 1 / 1.5 to 6, and even more preferably 1 / 2 to 4.

[0044] A polyether ether ketone compound represented by the above formula (1) is obtained by step B'. The polyether ether ketone compound represented by formula (1) may be used for a desired application as a varnish of the organic solvent used in step B' as it is, or after step B', it may be purified and isolated by any known method, for example, by reprecipitation by adding a poor solvent to the mixture after step B', and the obtained solid powder may be used for a desired application. EXAMPLES

[0045] The present invention will be described in detail below with reference to examples and comparative examples. However, the present invention is not limited to the following examples. In the examples and comparative examples, "room temperature" means 25°C.

[0046] Example 1 Synthesis of polyether ether ketone compound A-1 52.37g (0.24 mol) of 4,4'-difluorobenzophenone, 68.49g (0.30 mol) of 2,2-bis(4-hydroxyphenyl)propane, 74.63g of potassium carbonate, 300g of N-methyl-2-pyrrolidone, and 150g of toluene were added to a 1L glass four-neck flask equipped with a stirrer, a Dean-Stark tube, a cooling condenser, and a thermometer, and the toluene was refluxed at 130-140°C for 4 hours. Next, the mixture in the flask was heated to 170-180°C, and stirred for 10 hours while distilling off the toluene. After the reaction was completed, the mixture in the flask was cooled to room temperature, then poured into methanol to recover the precipitate, which was washed several times with pure water and methanol, and then dried in a dryer at 100°C for 12 hours to obtain a white powder with a yield of 93%. 1 The H-NMR spectrum is shown in Figure 1, and the FT-IR spectrum is shown in Figure 2. From these results, it was found that the product was a polyether ether ketone compound (number average molecular weight: 6000) having hydroxyl groups at both ends and represented by the following structure. [ka] n≒15 (average value) Below 1The peak assignments of the H-NMR spectrum are shown. 1 H-NMR (400MHz, CDCl3) δ=1.68(s, 2H, -CH3), δ1.73(s, 6H, -CH3), 6.7-7.8(m, 21H, Ar-H)

[0047] In a 1L glass four-neck flask equipped with a stirrer, a Dean-Stark tube, a cooling condenser and a thermometer, 15.00 g of the polyether ether ketone compound having hydroxyl groups at both ends obtained above, 11.68 g (0.06 mol) of 2,3,4,5,6-pentafluorostyrene, 20.78 g of potassium carbonate and 100 g of N,N-dimethylformamide were added and stirred at 40 to 50°C for 12 hours. After the reaction was completed, the mixture in the flask was cooled to room temperature, toluene was added to the flask, the mixture was washed several times with pure water and poured into methanol. The precipitate was collected and dried at 50°C for 12 hours to obtain the product as a white-brown powder with a yield of 93%. The product 1 The H-NMR spectrum is shown in Figure 3, and the FT-IR spectrum is shown in Figure 4. From these results, it was found that the product was a polyether ether ketone compound (number average molecular weight: 6700) having fluorostyryl groups at both ends, as represented by the following structure. [ka] n≒15 (average value) Below 1 The peak assignments of the H-NMR spectrum are shown. 1 H-NMR (400MHz, CDCl3) δ=1.71(s, 2H, -CH3), δ1.73(s, 6H, -CH3) δ5.74(d, 0.3H, -CH =CH), δ6.13(d, 0.3H, -CH=CH), δ6.71(m, 0.3H, -CH=CH), δ6.91-7.81(m, 25H, Ar-H)

[0048] Comparing the spectra in Figures 2 and 4, the 3500 cm -1 The absorption due to the hydroxyl group in the vicinity disappears, and the absorption at 1700cm -1A new signal derived from C=C was observed nearby.

[0049] Example 2 Synthesis of polyether ether ketone compound A-2 In a 1L glass four-neck flask equipped with a stirrer, a Dean-Stark tube, a cooling condenser and a thermometer, 52.37g (0.24 mol) of 4,4'-difluorobenzophenone, 103.94 (0.30 mol) of 1,3-bis[2-(4-hydroxyphenyl)-2-propyl]benzene, 74.63g of potassium carbonate, 300g of N-methyl-2-pyrrolidone and 150g of toluene were added, and the toluene was refluxed at 130-140°C for 4 hours. Next, the mixture in the flask was heated to 170-180°C and stirred for 10 hours while distilling off the toluene. After the reaction was completed, the mixture in the flask was cooled to room temperature, then poured into methanol to recover the precipitate, which was washed several times with pure water and methanol, and then dried in a dryer at 100°C for 12 hours to obtain a white powder with a yield of 95%. 1 From the H-NMR spectrum, it was found that the product was a polyether ether ketone compound (number average molecular weight: 6000) having hydroxyl groups at both ends and represented by the following structure. [ka] n≒11 (average value)

[0050] In a 1L glass four-neck flask equipped with a stirrer, a Dean-Stark tube, a cooling condenser and a thermometer, 15.00 g of the polyether ether ketone compound having hydroxyl groups at both ends obtained above, 11.68 g (0.06 mol) of 2,3,4,5,6-pentafluorostyrene, 20.78 g of potassium carbonate and 100 g of N,N-dimethylformamide were added and stirred at 40 to 50°C for 12 hours. After the reaction was completed, the mixture in the flask was cooled to room temperature, toluene was added to the flask, the mixture was washed several times with pure water and poured into methanol. The precipitate was collected and dried at 50°C for 12 hours to obtain the product as a white-brown powder with a yield of 92%. The product 1The results of the H-NMR spectrum revealed that the compound was a polyether ether ketone compound (number average molecular weight: 6900) having fluorostyryl groups at both ends, as represented by the structure below. [ka] n≒11 (average value)

[0051] Example 3 Synthesis of polyether ether ketone compound A-3 In a 1L glass four-neck flask equipped with a stirrer, a Dean-Stark tube, a cooling condenser and a thermometer, 45.82g (0.21 mol) of 4,4'-difluorobenzophenone, 77.96g (0.23 mol) of 1,3-bis[2-(4-hydroxyphenyl)-2-propyl]benzene, 107.80g of potassium carbonate, 450g of N-methyl-2-pyrrolidone and 170g of toluene were added, and the toluene was refluxed at 130-140°C for 4 hours. Next, the mixture in the flask was heated to 170-180°C, and stirred for 10 hours while distilling off the toluene. After the reaction was completed, the mixture in the flask was cooled to room temperature, then poured into methanol to collect the precipitate, washed several times with pure water and methanol, and dried in a dryer at 100°C for 12 hours to obtain a polyether ether ketone compound having hydroxyl groups at both ends (white powder, number average molecular weight: 18000, n≒33 (average value)).

[0052] In a 1 L glass four-neck flask equipped with a stirrer, a Dean-Stark tube, a cooling condenser and a thermometer, 15.00 g of the polyether ether ketone compound having hydroxyl groups at both ends obtained above, 1.51 g (0.008 mol) of 2,3,4,5,6-pentafluorostyrene, 2.68 g of potassium carbonate and 100 g of N,N-dimethylformamide were added and stirred at 40 to 50°C for 12 hours. After the reaction was completed, the mixture in the flask was cooled to room temperature, toluene was added to the flask, the mixture was washed several times with pure water and poured into methanol. The precipitate was collected and dried at 50°C for 12 hours to obtain the product as a pale yellow powder with a yield of 93%. The product 1From the H-NMR spectrum, it was found that the product was a polyether ether ketone compound (number average molecular weight: 19,000) having a fluorostyryl group at the end, as represented by the following structure. [ka] n≒33 (average value)

[0053] Example 4 Synthesis of polyether ether ketone compound A-4 In a 1L glass four-neck flask equipped with a stirrer, a Dean-Stark tube, a cooling condenser and a thermometer, 45.82g (0.21 mol) of 4,4'-difluorobenzophenone, 75.36g (0.22 mol) of 1,3-bis[2-(4-hydroxyphenyl)-2-propyl]benzene, 107.80g of potassium carbonate, 450g of N-methyl-2-pyrrolidone and 170g of toluene were added, and the toluene was refluxed at 130-140°C for 4 hours. Next, the mixture in the flask was heated to 170-180°C and stirred for 10 hours while distilling off the toluene. After the reaction was completed, the mixture in the flask was cooled to room temperature, then put into methanol to collect the precipitate, washed several times with pure water and methanol, and dried in a dryer at 100°C for 12 hours to obtain a polyether ether ketone compound having a hydroxyl group at the end (white powder, number average molecular weight: 30000, n≒59 (average value)).

[0054] In a 1 L glass four-neck flask equipped with a stirrer, a Dean-Stark tube, a cooling condenser and a thermometer, 15.00 g of the polyether ether ketone compound having a hydroxyl group at the end obtained above, 0.77 g (0.004 mol) of 2,3,4,5,6-pentafluorostyrene, 1.37 g of potassium carbonate and 100 g of N,N-dimethylformamide were added and stirred at 40 to 50°C for 12 hours. After the reaction was completed, the mixture in the flask was cooled to room temperature, toluene was added to the flask, the mixture was washed several times with pure water and poured into methanol. The precipitate was collected and dried at 50°C for 12 hours to obtain the product as a pale yellow powder with a yield of 92%. The product 1From the H-NMR spectrum, it was found that the product was a polyether ether ketone compound (number average molecular weight: 31,000) having a fluorostyryl group at the end, as represented by the following structure. [ka] n≒59 (average value)

[0055] Example 5 Synthesis of polyether ether ketone compound A-5 In a 1L glass four-neck flask equipped with a stirrer, a Dean-Stark tube, a cooling condenser and a thermometer, 15.00 g of the polyether ether ketone compound having a hydroxyl group at the end synthesized in Example 2, 0.006 g (0.02 mmol) of tetra-n-butylammonium bromide, 30 g of toluene and 1 g of a 50% aqueous sodium hydroxide solution were added and stirred at room temperature for 30 minutes. Next, 1.06 g (0.007 mol) of vinylbenzyl chloride (p-isomer: m-isomer = 45-55: 45-55) was dropped into the flask and reacted at 65°C for 12 hours. After the reaction was completed, the mixture was cooled to room temperature, washed with water five times and then poured into methanol. The precipitate was collected by filtration and dried in a dryer at 70°C for 12 hours to obtain the product (light yellow powder) in a yield of 92%. The product 1 From the H-NMR spectrum, it was found that the product was a polyether ether ketone compound (number average molecular weight: 6800) having a vinyl benzyl ether group at the end, as represented by the following structure. [ka] n≒11 (average value)

[0056] Comparative Example 1 (A'-1) In a 1L glass four-neck flask equipped with a stirrer, a Dean-Stark tube, a cooling condenser and a thermometer, 65.46g (0.30 mol) of 4,4'-difluorobenzophenone, 54.79g (0.24 mol) of 2,2-bis(4-hydroxyphenyl)propane, 74.63g of potassium carbonate, 300g of N-methyl-2-pyrrolidone and 150g of toluene were added, and the toluene was refluxed at 130-140°C for 4 hours. Next, the mixture in the flask was heated to 170-180°C, and stirred for 10 hours while distilling off the toluene. After cooling the mixture in the flask to room temperature, 13.10g (0.12 mol) of 4-aminophenol, 1.0g of potassium carbonate, 30g of N-methyl-2-pyrrolidone and 15g of toluene were added, and the toluene was refluxed at 130-140°C for 3 hours. Next, the mixture in the flask was heated to 170-180°C and reacted for 4 hours while distilling off toluene. After the reaction was completed, the mixture in the flask was cooled to room temperature and then poured into methanol to recover the precipitate, which was washed several times with pure water and methanol and then dried in a dryer at 100°C for 12 hours to obtain a polyether ether ketone compound (white powder) having amino groups at both ends.

[0057] Next, 30 g of the polyether ether ketone compound having an amino group at the end obtained above, 2.17 g (0.02 mol) of maleic anhydride, and 100 g of anisole were added to a 1 L glass four-neck flask equipped with a stirrer, Dean-Stark tube, cooling condenser, and thermometer, and the mixture was stirred at room temperature for 1 hour to synthesize an amic acid, after which the temperature was raised to 150°C and the reaction was carried out for 5 hours. After the reaction was completed, the mixture in the flask was cooled to room temperature and poured into methanol to recover the precipitate, which was washed several times with methanol and then dried in a dryer at 100°C for 12 hours to obtain the product (white powder) in a yield of 93%. 1 From the H-NMR spectrum, it was found that the product was a polyether ether ketone compound (number average molecular weight: 6600) having maleimide groups at both ends, as represented by the following structure. [ka] n≒15 (average value)

[0058] (A'-2): Liquid bisphenol A type epoxy resin (epoxy equivalent 180, "jER828EL" manufactured by Japan Epoxy Resin Co., Ltd.)

[0059] (A'-3): Bismaleimide compound represented by the following formula (SLK-3000, manufactured by Shin-Etsu Chemical Co., Ltd., number average molecular weight: 7200) [ka] (In the formula, C 36 H 70 is a hydrocarbon group derived from dimer acid. n≒5 (average value)

[0060] [Table 1] As shown in Table 1 above, the polyether ether ketone compound of the present invention can be synthesized more simply than the polyether ether ketone compound synthesized in Comparative Example 1 by shortening one reaction step.

[0061] <Solubility of polyetheretherketone in solvents> The solubility of the polyether ether ketone compounds (A-1), (A-2), (A-3), (A-4) and (A-5) as well as PEEK (commercially available PEEK powder, polyether ether ketone, VICTREX151G, melting point 343°C, Tg 147°C) as a comparative compound in various solvents was evaluated, and the evaluation results are shown in Table 2. The solvent solubility was evaluated by adding each solvent to the compound to be evaluated so that the non-volatile content was 50% by mass. If it dissolves uniformly (no insoluble matter) and flows, it is considered a good result. If it does not dissolve (contains insoluble matter) or does not flow, mark it as "X". The solvents used were chloroform, THF (tetrahydrofuran), toluene, DMSO (dimethylsulfoxide) and NMP (N-methyl-2-pyrrolidone).

[0062] [Table 2]

[0063] <Preparation of cured resin film> Polyether ether ketone compounds (A-1), (A-2), (A-3), (A-4) and (A-5) as well as comparative compounds (A'-1), (A'-2) and (A'-3) were each dissolved in toluene to prepare a toluene varnish having a non-volatile content of 65% by mass. To a toluene varnish containing (A-1), (A-2), (A-3), (A-4), (A-5), (A'-1) or (A'-3), 0.2 g of dicumyl peroxide (Percumyl D, manufactured by NOF Corp.) was added per 10 g of solids, and the mixture was thoroughly stirred at room temperature to obtain a varnish-like composition. To the toluene varnish containing (A'-2), 0.1 g of 2-ethyl-4-methylimidazole (2E4MZ: manufactured by Shikoku Kasei Holdings Co., Ltd.) was added per 10 g of solid content to obtain a varnish-like composition in the same manner. The varnish-like composition of each example was applied to a support film made of a PET film with a thickness of 38 μm using a roller coater, and dried at 100° C. for 10 minutes to remove the solvent, obtaining an uncured resin film. A frame with a diameter of 200 mm and a thickness of 200 μm was prepared, and the uncured resin film was sandwiched between 50 μm-thick release-treated PET films (E7006, manufactured by Toyobo Co., Ltd.), and the uncured resin film was pressed at 160° C. for 5 minutes at 4.5 kgf / cm using a vacuum press (manufactured by Nikko Materials Co., Ltd.). 2 The mixture was molded under the above conditions and post-cured at 180°C for 3 hours to obtain a cured product (cured resin film).

[0064] <Dielectric properties> Using the cured resin film prepared above, a network analyzer (E5063-2D5 manufactured by Keysight Corporation) was connected to a strip line (manufactured by Keycom Corporation) to measure the relative dielectric constant and dielectric loss tangent of the cured resin film at a frequency of 10 GHz. The relative dielectric constant was Dk and the dielectric loss tangent was Df, and the results are shown in Table 3.

[0065] <Hygroscopicity> The cured resin film prepared above was stored for 24 hours under conditions of 85°C and 85% humidity, and the cured resin film after storage was used to connect a network analyzer (E5063-2D5 manufactured by Keysight) and a strip line (manufactured by Keycom Co., Ltd.) to measure the relative dielectric constant and dielectric loss tangent of the cured resin film at a frequency of 10 GHz. The results are shown in Table 3.

[0066] <Heat resistance> The cured resin film prepared above was stored at 150°C for 1000 hours, and the cured resin film after storage was used to connect a network analyzer (E5063-2D5 manufactured by Keysight) and a strip line (manufactured by Keycom Co., Ltd.) to measure the relative dielectric constant and dielectric loss tangent of the cured resin film at a frequency of 10 GHz. The results are shown in Table 3.

[0067] <Coefficient of Thermal Expansion (CTE)> The coefficient of thermal expansion (CTE) of the cured resin film was measured using a TMA-Q400 made by TA Instruments. The coefficient of thermal expansion was calculated from values ​​in the range of 0 to 40° C. The results are shown in Table 3.

[0068] [Table 3]

[0069] From the above results, it was found that the polyether ether ketone compound of the present invention has excellent dielectric properties (low relative dielectric constant and low dielectric tangent), high heat resistance, and low moisture absorption. The polyether ether ketone compound having a maleimide group at its end in Comparative Example 1 had excellent dielectric properties, high heat resistance, and low moisture absorption, but had disadvantages in production such as many synthesis steps and long reaction times as shown in Table 1. The compound in Comparative Example 2 had low CTE but insufficient dielectric properties. The compound in Comparative Example 3 showed excellent dielectric properties but a high CTE value.

Claims

1. A polyether ether ketone compound represented by the following formula (1): 【Chemistry 1】 (In formula (1), R 1 and R 2 each independently represents a substituted or unsubstituted aromatic group; each R' independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a halogen atom; A 1 and A 2 each independently represents a single bond or an alkylene group having 1 to 4 carbon atoms, and n is a number from 1 to 100.

2. In formula (1), R 1 and R 2 Each of the radicals independently represents a group having an aromatic structure having 6 to 30 carbon atoms.

3. The polyether ether ketone compound according to claim 1, wherein the number average molecular weight of the polyether ether ketone compound represented by formula (1) is 700 to 50,000.

4. 4,4'-difluorobenzophenone, The following formula (2) 【Chemistry 2】 (In formula (2), R represents a substituted or unsubstituted aromatic group.) and a compound represented by the formula: in the presence of an alkali metal carbonate to obtain a polyether ether ketone compound having hydroxyl groups at both ends; and the polyether ether ketone compound having hydroxyl groups at both ends obtained in step A; The following formula (3) 【Chemistry 3】 (In formula (3), X represents a chlorine atom, a bromine atom, or an iodine atom; R' each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a halogen atom; and A represents a single bond or an alkylene group having 1 to 4 carbon atoms.) and a compound represented by the formula: Step B: reacting in the presence of a base; or the polyether ether ketone compound having hydroxyl groups at both ends obtained in step A; 2,3,4,5,6-pentafluorostyrene, in the presence of an alkali metal carbonate. The method for producing the polyether ether ketone compound according to any one of claims 1 to 3, comprising:

5. The method for producing a polyether ether ketone compound according to claim 4, wherein in step A, 4,4'-difluorobenzophenone and the compound represented by formula (2) are reacted in a molar ratio of 4,4'-difluorobenzophenone / compound represented by formula (2)=1 / 1.01 to 2.0.

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