Method for producing polyester, and polymer

Abstract

Provided are a method with which it is possible to produce a high-molecular-weight polyester at a comparatively low temperature, and a polymer. Specifically disclosed is a method for producing a polyester, the method comprising: reacting at least one dicarboxylic acid compound selected from the group consisting of compounds represented by formula (1), formula (2), and formula (3) with a diol compound in the presence of a condensation catalyst; heating the resulting prepolymer at a temperature lower than the melting temperature of the prepolymer; and subjecting the prepolymer to solid-phase polymerization while discharging a fluorine-containing alcohol (A3) produced as a by-product to the outside of the system. Ar is a divalent aromatic hydrocarbon group or a divalent aromatic heterocyclic group; R1 is CX1Y1R4; R2 is H or CX2Y2R5; R3 is H or CX3Y3R6; R7 is a perfluoroalkylene group; each of X1 to X3 is H, F, or Rf; each of Y1 to Y3 is F or Rf; each of R4 to R6 is F, Rf, ORf, or an alkyl group; and Rf is a fluoroalkyl group.

Description

Polyester manufacturing method and polymer

[0001] This invention relates to a method for producing polyester and to polymers.

[0002] Polyester is used in a variety of applications, including fibers, films, and containers, due to its excellent mechanical properties and moldability. In particular, polyarylate, a polycondensate of aromatic dicarboxylic acid and aromatic diol, exhibits various excellent properties in addition to its mechanical properties and moldability, such as heat resistance, flame retardancy, impact resistance, bending recovery, UV barrier properties, chemical resistance, and electrical properties, and is therefore widely used in many industrial fields as an engineering plastic.

[0003] The following methods are known for producing polyarylates: (i) Interfacial polycondensation method between an alkali metal salt or alkaline earth metal salt of an aromatic diol compound and a dicarboxylic acid dichloride. (ii) Deacetase polycondensation method (melt polycondensation method) between a diacetate salt of an aromatic diol compound and a dicarboxylic acid. (iii) Dephenol polycondensation method (melt polycondensation method) between a diphenyl ester of a dicarboxylic acid and an aromatic diol compound.

[0004] However, method (i) has problems such as the use of large amounts of solvents such as methylene chloride; the need to wash and remove the salts produced by the reaction; and the residue of impurities such as solvents remaining in the polyarylate. In methods (ii) and (iii), although the raw materials can be synthesized from various dicarboxylic acid derivatives, the reaction is carried out at high temperatures, making them prone to discoloration due to the influence of oxygen, etc. Also, because the melt viscosity of the reaction system becomes extremely high at the end of the reaction, it becomes difficult to efficiently remove reaction by-products such as water, monocarboxylic acids, and phenols from the reaction system. Therefore, it is necessary to carry out the polycondensation reaction at high temperatures for a long time to increase the molecular weight to the desired level. In addition, if monocarboxylic acids or phenols remain in the polyarylate, it can cause discoloration and a decrease in strength of the polyarylate.

[0005] In the melt polycondensation method, the following methods are known for producing high molecular weight polyester with minimal coloration: (iv) A method of transesterifying a specific fluorine dicarboxylic acid ester compound and a diol compound in the presence of a catalyst (see Patent Document 1).

[0006] International Publication No. 2012 / 118084

[0007] However, in method (iv), the transesterification reaction is carried out at high temperature, so there is room for improvement in suppressing discoloration. Furthermore, there is a need for even higher molecular weight polyesters. The present invention provides a method and polymer that can produce high molecular weight polyester at a relatively low temperature.

[0008] The inventors of this invention, after diligently studying the above-mentioned problems, focused on solid-phase polymerization. Solid-phase polymerization is a method of polymerizing a prepolymer while maintaining its solid state, thereby obtaining a polymer with a larger molecular weight than the prepolymer. Because the prepolymer is polymerized in a solid state, polymerization can be carried out at relatively low temperatures. However, it was generally accepted that prepolymers used to produce polyester by solid-phase polymerization are crystalline, and that solid-phase polymerization cannot be applied to amorphous prepolymers. This was because, due to the low molecular mobility of monomers or prepolymers during polymerization, crystalline properties were considered essential to keep the reaction sites in close proximity. However, after further investigation, the inventors discovered that solid-phase polymerization can be applied to amorphous prepolymers by using a specific dicarboxylic acid compound, thus completing the present invention.

[0009] In other words, the present invention has the following aspects: [1] A method for producing polyester, comprising reacting at least one dicarboxylic acid compound selected from the group consisting of a compound represented by formula (1), a compound represented by formula (2), and a compound represented by formula (3) below with a diol compound in the presence of a condensation catalyst, heating the resulting prepolymer at a temperature below its melting point, and solid-phase polymerizing the prepolymer while discharging the by-product fluorine-containing alcohol (A3) from the system.

[0010]

[0011] However, Ar is a divalent aromatic hydrocarbon group or a divalent aromatic heterocyclic group, and R １ is a group represented by CX １ Y １ R ４ The two Rs １ may be the same or different. R ２ is a hydrogen atom or a group represented by CX ２ Y ２ R ５ The two Rs ２ may be the same or different. R ３ is a hydrogen atom or a group represented by CX ３ Y ３ R ６ The two Rs ３ may be the same or different. X １ to X ３ are each independently a hydrogen atom, a fluorine atom or R ｆ Y １ to Y ３ are each independently a fluorine atom or R ｆ R ４ to R ６ are each independently a fluorine atom, R ｆ OR ｆ or an alkyl group having 1 to 6 carbon atoms. R ｆ is independently a fluoroalkyl group having 1 to 4 carbon atoms or a fluoroalkyl group having an etheric oxygen atom having 2 to 4 carbon atoms.

[0012]

[0013] However, Ar is a divalent aromatic hydrocarbon group or a divalent aromatic heterocyclic group, and R １ is a group represented by CX １ Y １ R ４ The two Rs ２ may be the same or different. R ２ is a hydrogen atom or a group represented by CX ２ Y ５ R ３ is a hydrogen atom or a group represented by CX ３ Y ３ R６ It is a group represented by R ７ X is a perfluoroalkylene group having 1 to 5 carbon atoms (however, it may also contain an etheric oxygen atom), １ ~X ３ Each is independently a hydrogen atom, a fluorine atom, or R ｆ Y １ ~Y ３ Each of these is independently a fluorine atom or R ｆ And R ４ ~R ６ Each of these is an independent fluorine atom, R ｆ , OR ｆ Or an alkyl group having 1 to 6 carbon atoms, R ｆ These are independently fluoroalkyl groups having 1 to 4 carbon atoms or fluoroalkyl groups having 2 to 4 carbon atoms and an etheric oxygen atom.

[0014]

[0015] However, Ar is a divalent aromatic hydrocarbon group or a divalent aromatic heterocyclic group, and R ７ This is a perfluoroalkylene group having 1 to 5 carbon atoms (however, it may also contain an etheric oxygen atom), and has two R ７ They may be the same or different.

[0016] [2] The method for producing polyester according to [1], wherein the compound represented by formulas (1) to (3) is obtained by a reaction using at least one fluorine-containing alcohol (A1) selected from the group consisting of the compound represented by formula (5) and the compound represented by formula (6) below as a starting material.

[0017]

[0018] However, R １ CX １ Y １ R ４ It is a group represented by R ２ is a hydrogen atom or CX ２ Y ２ R ５ It is a group represented by R ３ is a hydrogen atom or CX３ Y ３ R ６ It is a group represented by R ７ X is a perfluoroalkylene group having 1 to 5 carbon atoms (however, it may also contain an etheric oxygen atom), １ ~X ３ Each is independently a hydrogen atom, a fluorine atom, or R ｆ Y １ ~Y ３ Each of these is independently a fluorine atom or R ｆ And R ４ ~R ６ Each of these is an independent fluorine atom, R ｆ , OR ｆ Or an alkyl group having 1 to 6 carbon atoms, R ｆ These are independently fluoroalkyl groups having 1 to 4 carbon atoms or fluoroalkyl groups having 2 to 4 carbon atoms and an etheric oxygen atom.

[0019] [3] R in formula (5) above ２ However, CX ２ Y ２ R ５A method for producing polyester according to [2] above, wherein the group is represented by [2]. [4] A method for producing polyester according to any one of [1] to [3] above, wherein the number of carbon atoms of the fluorine-containing alcohol (A3) is 2 to 10. [5] A method for producing polyester according to any one of [1] to [4] above, wherein the pKa of the fluorine-containing alcohol (A3) is less than 15. [6] A method for producing polyester according to any one of [1] to [5] above, wherein the pKa of the fluorine-containing alcohol (A3) is less than 13. [7] The method for producing a polyester according to any one of [1] to [6], wherein the fluorine-containing alcohol (A3) is at least one selected from the group consisting of 2,2,2-trifluoroethanol, 2,2,3,3-tetrafluoro-1-propanol, 2,2,3,3,3-pentafluoro-1-propanol, 1,1,1,3,3,3-hexafluoro-2-propanol, 2-fluoro-1-propanol, 2,2,3,4,4,4-hexafluoro-1-butanol, 2,2,3,3,4,4,5,5-octafluoro-1-pentanol, 2,2,3,3,4,4,5,5-octafluorocyclopentanol, perfluoro(t-butyl) alcohol, and 2,2,3,3,4,4,5,5,6,6-decafluorocyclohexanol. [8] The method for producing polyester according to any one of [1] to [7], wherein the diol compound is an aromatic diol compound. [9] The method for producing polyester according to any one of [1] to [8], wherein the diol compound is bisphenol A.

[10] The method for producing polyester according to any one of [1] to [7], wherein the diol compound is an alicyclic diol compound.

[11] The method for producing polyester according to any one of [1] to

[10] , wherein the condensation catalyst is a nitrogen-containing compound.

[12] The method for producing polyester according to

[11] , wherein the pKa of the nitrogen-containing compound is 9 to 15.

[13] The method for producing polyester according to

[11] or

[12] , wherein the vapor pressure of the nitrogen-containing compound is 1 to 10,000 Pa.

[14] The method for producing a polyester according to any one of [1] to

[13] above, wherein the compound represented by the formula (1) is at least one of bis(1,1,1,3,3,3-hexafluoropropyl) isophthalate represented by the following formula (1-1) and bis(1,1,1,3,3,3-hexafluoropropyl) terephthalate represented by the following formula (1-2).

[0020]

[0021]

[15] A polymer represented by any one of the following formula (P1), formula (P2) and formula (P3).

[0022]

[0023] However, G1 is a monovalent group represented by the following formula (g1), a monovalent group represented by the following formula (g2) or a hydrogen atom, G2 is a hydrogen atom, Ar is a divalent aromatic hydrocarbon group or a divalent aromatic heterocyclic group, X ４ is a divalent group derived from an alicyclic diol compound, and m is an integer of 10 to 1000.

[0024]

[0025] However, R １ is a group represented by CX １ Y １ R ４ is a group represented by R ２ is a hydrogen atom or a group represented by CX ２ Y ２ R ５ is a group represented by R ３ is a hydrogen atom or a group represented by CX ３ Y ３ R ６ is a group represented by R ７ is a perfluoroalkylene group having 1 to 5 carbon atoms (however, it may contain an etheric oxygen atom), X １ to X ３ are each independently a hydrogen atom, a fluorine atom or R ｆ and Y １ to Y ３ are each independently a fluorine atom or R ｆ and R４ ~R ６ Each of these is an independent fluorine atom, R ｆ , OR ｆ Or an alkyl group having 1 to 6 carbon atoms, R ｆ These are independently fluoroalkyl groups having 1 to 4 carbon atoms or fluoroalkyl groups having 2 to 4 carbon atoms and an etheric oxygen atom.

[0026]

[16] At least one of G1 in formula (P1) and formula (P3), and G2 in formula (P1) and formula (P2) is substituted with a substituent, where if G1 is substituted, the substituent is substituent (S1) or substituent (S2), where if G2 is substituted, the substituent is substituent (S3) or substituent (S4), and the substituent (S1) is a monovalent group obtained by removing a hydroxyl group from at least one compound (s1) selected from the group consisting of phenol, cresol, p-t-butylphenol, 2,3,5-trimethylphenol, 2,3,6-trimethylphenol, and cumylphenol. The polymer according to

[15] , wherein the substituent (S2) is a monovalent group obtained by removing a hydroxyl group from at least one compound (s2) selected from the group consisting of methanol, ethanol, n-propanol, isopropanol, n-butanol, 2-butanol, pentanol, hexanol, dodecyl alcohol, stearyl alcohol, benzyl alcohol, and phenethyl alcohol; the substituent (S3) is a monovalent group obtained by removing a chlorine atom from at least one compound (s3) selected from the group consisting of benzoic acid chloride, methanesulfonyl chloride, and phenyl chloroformate; and the substituent (S4) is a monovalent group obtained by removing an OH from the carboxylic acid of at least one compound (s4) selected from the group consisting of acetic acid, propionic acid, octanoic acid, cyclohexanecarboxylic acid, benzoic acid, toluic acid, phenylacetic acid, p-t-butylbenzoic acid, and p-methoxyphenylacetic acid.

[0027] According to the present invention, a method and polymer can be provided for producing high molecular weight polyester at a relatively low temperature.

[0028] The present invention will now be described in detail. The following embodiments are merely illustrative for illustrating the present invention and are not intended to limit the present invention to these embodiments. The present invention can be implemented in various forms without departing from its spirit. In this specification and in the claims, a numerical range represented by "~" means a numerical range that includes the numbers before and after "~" as the lower and upper limits. For example, A to B is synonymous with A or greater and B or less. The numerical ranges of content, various physical properties, and property values ​​disclosed herein can be combined with their lower and upper limits to create new numerical ranges.

[0029] In this specification, the compound represented by formula (1) is referred to as "compound (1)". Compounds represented by other formulas are referred to similarly. Furthermore, the fluorine-containing alcohol that is a raw material for the dicarboxylic acid compound is referred to as "fluorine-containing alcohol (A1)". The fluorine-containing alcohol produced as a by-product of the condensation reaction between the dicarboxylic acid compound and the diol compound is referred to as "fluorine-containing alcohol (A2)". The fluorine-containing alcohol produced as a by-product of the solid-phase polymerization of the "prepolymer" is referred to as "fluorine-containing alcohol (A3)".

[0030] The meanings and definitions of terms used in this invention are as follows: "Etheric oxygen atom" means an oxygen atom that forms an ether bond. "Prepolymer" means a solid intermediate product obtained by stopping the condensation reaction between the raw material dicarboxylic acid compound and diol compound at an appropriate point, and is a polyester with a weight-average molecular weight lower than the high molecular weight polyester obtained by solid-phase polymerization. "Solid-phase polymerization" means a polymerization method that obtains a high molecular weight polyester by polymerizing the prepolymer while maintaining the solid state of the prepolymer. "Melting temperature of prepolymer" means the temperature at which the prepolymer melts, becomes liquid, or softens. The prepolymer is heated to a predetermined temperature, and the temperature at which it becomes liquid or softens is determined by visual confirmation. "Weight-average molecular weight" and "number-average molecular weight" are values ​​on a standard polystyrene basis measured by gel permeation chromatography (GPC). "Glass transition temperature" is the temperature measured by differential scanning calorimetry (DSC) as the intermediate glass transition temperature in accordance with JIS K 7121:2012. "Crystallization" refers to an operation to increase the crystallinity of a polymer. "Perfluoroalkylene group" refers to a group in which all hydrogen atoms of an alkylene group are replaced with fluorine atoms. "Fluoroalkyl group" refers to a group in which some or all hydrogen atoms of an alkyl group are replaced with fluorine atoms.

[0031] [Method for Producing Polyester] A method for producing polyester according to one aspect of the present invention comprises the following steps a and b. In addition to steps a and b, the method for producing polyester may further comprise the following step c as needed. Step a: A step of reacting a specific dicarboxylic acid compound and a diol compound in the presence of a condensation catalyst to obtain a prepolymer. Step b: A step of solid-phase polymerization of the prepolymer to obtain a polyester. Step c: A step of substituting the ends of the polyester obtained in step b with substituents.

[0032] <Dicarboxylic acid compounds> Dicarboxylic acid compounds are at least one compound selected from the group consisting of compound (1), compound (2), and compound (3), and are also referred to as "fluorine-containing dicarboxylic acid ester compounds" in this specification.

[0033]

[0034] However, Ar is a divalent aromatic hydrocarbon group or a divalent aromatic heterocyclic group, and R １ CX １ Y １ R ４ It is a group represented by two R １ They may be the same or different, R ２ is a hydrogen atom or CX ２ Y ２ R ５ It is a group represented by two R ２ They may be the same or different, R ３ is a hydrogen atom or CX ３ Y ３ R ６ It is a group represented by two R ３ X may be the same or different, １ ~X ３ Each is independently a hydrogen atom, a fluorine atom, or R ｆ Y １ ~Y ３ Each of these is independently a fluorine atom or R ｆ And R ４ ~R ６ Each of these is an independent fluorine atom, R ｆ , OR ｆ Or an alkyl group having 1 to 6 carbon atoms, R ｆ These are independently fluoroalkyl groups having 1 to 4 carbon atoms or fluoroalkyl groups having 2 to 4 carbon atoms and an etheric oxygen atom.

[0035]

[0036] However, Ar is a divalent aromatic hydrocarbon group or a divalent aromatic heterocyclic group, and R １ CX １ Y １ R ４ It is a group represented by R ２ is a hydrogen atom or CX ２ Y ２ R ５ It is a group represented by R ３ is a hydrogen atom or CX３ Y ３ R ６ It is a group represented by R ７ X is a perfluoroalkylene group having 1 to 5 carbon atoms (however, it may also contain an etheric oxygen atom), and １ ~X ３ Each is independently a hydrogen atom, a fluorine atom, or R ｆ Y １ ~Y ３ Each of these is independently a fluorine atom or R ｆ And R ４ ~R ６ Each of these is an independent fluorine atom, R ｆ , OR ｆ Or an alkyl group having 1 to 6 carbon atoms, R ｆ These are independently fluoroalkyl groups having 1 to 4 carbon atoms or fluoroalkyl groups having 2 to 4 carbon atoms and an etheric oxygen atom.

[0037]

[0038] However, Ar is a divalent aromatic hydrocarbon group or a divalent aromatic heterocyclic group, and R ７ This is a perfluoroalkylene group having 1 to 5 carbon atoms (however, it may also contain an etheric oxygen atom), and has two R ７ They may be the same or different.

[0039] Ar may have one or more hydrogen atoms substituted with other substituents that do not adversely affect the reaction. Examples of other substituents include halogen atoms, C1-C10 alkyl groups, C1-C10 alkoxy groups, phenyl groups, phenoxy groups, vinyl groups, cyano groups, ester groups, amide groups, and nitro groups. Specific examples of Ar include phenylene groups, toluene groups, xylylene groups, biphenylene groups, naphthylene groups, furylene groups, thienylene groups, pyrrolylene groups, and pyridylene groups. Among these, groups with six or more members are preferred from the viewpoint of the heat resistance of the resulting polyester, and groups represented by the following formula (4) are more preferred from the viewpoint of the heat resistance of the resulting polyester and the availability of raw materials.

[0040]

[0041] However, p is an integer from 0 to 4, and R ８ Each of these is independently a halogen atom, a C1-C10 alkyl group, a C1-C10 alkoxy group, a 5-C10 membered cycloalkyl group, or a phenyl group, and R when p is 2-4 ８ These may be the same or different.

[0042] Specific examples of the group represented by formula (4) include 1,2-phenylene group, 1,3-phenylene group, 1,4-phenylene group, 3-methyl-1,2-phenylene group, 4-methyl-1,2-phenylene group, 2-methyl-1,3-phenylene group, 4-methyl-1,3-phenylene group, 5-methyl-1,3-phenylene group, 2-methyl-1,4-phenylene group, 3-phenyl-1,2-phenylene group, 4-phenyl-1,2-phenylene group, 2-phenyl-1,3-phenylene group, 4-phenyl-1,3-phenylene group, 5-phenyl-1,3-phenylene group, and 2-phenyl-1,4 Examples include -phenylene group, 3-t-butyl-1,2-phenylene group, 4-t-butyl-1,2-phenylene group, 2-t-butyl-1,3-phenylene group, 4-t-butyl-1,3-phenylene group, 5-t-butyl-1,3-phenylene group, 2-t-butyl-1,4-phenylene group, 3-cyclohexyl-1,2-phenylene group, 4-cyclohexyl-1,2-phenylene group, 2-cyclohexyl-1,3-phenylene group, 4-cyclohexyl-1,3-phenylene group, 5-cyclohexyl-1,3-phenylene group, and 2-cyclohexyl-1,4-phenylene group.

[0043] As the dicarboxylic acid compound, compound (1) is preferred from the viewpoint of the usefulness of the resulting polyester, especially polyarylate. Among these, at least one of compounds (1-1) and (1-2) is preferred because it enhances the desorption of the fluorine-containing alcohol (A2) produced as a by-product in step a and the fluorine-containing alcohol (A3) produced as a by-product in step b, and also enhances the discharge of the desorbed fluorine-containing alcohol (A2) and fluorine-containing alcohol (A3) from the reaction system. Compound (1-1) is bis(1,1,1,3,3,3-hexafluoropropyl) isophthalate. Compound (1-2) is bis(1,1,1,3,3,3-hexafluoropropyl) terephthalate. The high desorption of fluorine-containing alcohol (A2) and fluorine-containing alcohol (A3) is also preferable because it allows for lower reaction temperatures in steps a and b, and suppresses discoloration of the polyester.

[0044]

[0045] (Method for producing dicarboxylic acid compounds) Dicarboxylic acid compounds can be obtained, for example, by a reaction using at least one fluorine-containing alcohol (A1) selected from the group consisting of compound (5) and compound (6) as a starting material.

[0046]

[0047] However, R １ CX １ Y １ R ４ It is a group represented by R ２ is a hydrogen atom or CX ２ Y ２ R ５ It is a group represented by R ３ is a hydrogen atom or CX ３ Y ３ R ６ It is a group represented by R ７ X is a perfluoroalkylene group having 1 to 5 carbon atoms (however, it may also contain an etheric oxygen atom), and １ ~X ３ Each is independently a hydrogen atom, a fluorine atom, or R ｆ Y １ ~Y３ Each of these is independently a fluorine atom or R ｆ And R ４ ~R ６ Each of these is an independent fluorine atom, R ｆ , OR ｆ Or an alkyl group having 1 to 6 carbon atoms, R ｆ These are independently fluoroalkyl groups having 1 to 4 carbon atoms or fluoroalkyl groups having 2 to 4 carbon atoms and an etheric oxygen atom.

[0048] As for the fluorine-containing alcohol (A1), it is preferable that its degree of acid dissociation is higher than that of the diol compound, in order to improve the transesterification reaction rate. Therefore, secondary or tertiary compounds in which a fluoroalkyl group is directly bonded to the carbon atom at the α position of the hydroxyl group (hereinafter also referred to as "α-carbon") are preferred. However, alcohols in which a fluorine atom is directly bonded to the α-carbon are undesirable because they are prone to decomposition reactions due to dehydrofluoridation.

[0049] The pKa of the fluorine-containing alcohol (A1) is used as a measure of the degree of acid dissociation. When the diol compound is an aromatic diol compound, the pKa of the fluorine-containing alcohol (A1) is preferably less than 10 or close to 10, since the pKa of phenols is approximately 10. Examples of values ​​close to 10 include 8.5 to 10. When the diol compound is an aliphatic diol compound, the pKa of the fluorine-containing alcohol (A1) is preferably less than 15, and more preferably less than 13, since the pKa of aliphatic alcohols is approximately 15 to 16. The lower limit of the pKa of the fluorine-containing alcohol (A1) is not particularly limited, but for example, it is 5 or higher. The pKa of the fluorine-containing alcohol (A1) is the value at 25°C and can be obtained by a method similar to the value obtained by the measurement method below (*1) or the value obtained by the estimation method below (*3). If a catalog value or literature value is available, the catalog value or literature value may be used as the pKa of the fluorine-containing alcohol (A1).

[0050] As for compound (5), the more fluoroalkyl groups bonded to the α-carbon, the higher the degree of acid dissociation of the fluorine-containing alcohol (A1), therefore, R ２ CX ２Y ２ R ５ A group represented by , i.e., a secondary or tertiary fluorine-containing alcohol is preferred, and among these, a secondary fluorine-containing alcohol, i.e., R, is preferred because it enhances the stability of the dicarboxylic acid compound. ２ CX ２ Y ２ R ５ It is a group represented by R ３ Compounds in which the atom is a hydrogen atom are more preferable.

[0051] The carbon number of the fluorinated alcohol (A1) is preferably 2 to 10. If the carbon number of the fluorinated alcohol (A1) is 2 or more, a stable fluorinated alcohol (A1) can be selected in which the fluorine atom is not directly bonded to the α-position of the hydroxyl group. If the carbon number of the fluorinated alcohol (A1) is 10 or less, when the fluorinated alcohol (A2) and fluorinated alcohol (A3) that are removed during the transesterification reaction are discharged from the reaction system, their boiling points will be such that they can be easily removed under mild conditions. Therefore, it is not necessary to apply high temperatures during the transesterification reaction, and high-quality polyester can be produced.

[0052] A specific example of a fluorine-containing alcohol (A1) is 2,2,2-trifluoroethanol (pKa: 12.4 ※２ ), 2,2,3,3-tetrafluoro-1-propanol (pKa: 12.7 ※３ ), 2,2,3,3,3-pentafluoro-1-propanol (pKa: 12.5 ※２ ), 1,1,1,3,3,3-hexafluoro-2-propanol (pKa: 9.4 ※１ ), 2-fluoro-1-propanol (pKa: 14.0 ※３ ), 2,2,3,4,4,4-hexafluoro-1-butanol (pKa: 12.5 ※３ ), 2,2,3,3,4,4,5,5-octafluoro-1-pentanol (pKa: 12.5 ※３ ), 2,2,3,3,4,4,5,5-octafluorocyclopentanol (pKa: 8.5 ※１ ), perfluoro(t-butyl) alcohol (pKa: 5.3 ※１), 2,2,3,3,4,4,5,5,6,6-decafluorocyclohexanol (pKa: 8.5 ※１ Examples include the following. Among these, 2,2,2-trifluoroethanol, 2,2,3,3-tetrafluoro-1-propanol, 2,2,3,3,3-pentafluoro-1-propanol, and 1,1,1,3,3,3-hexafluoro-2-propanol are preferred, and 1,1,1,3,3,3-hexafluoro-2-propanol is more preferred, as they offer improved detachability of fluorine-containing alcohols (A2) and fluorine-containing alcohols (A3) and their ability to be discharged from the reaction system, as well as being readily available industrially and facilitating the production of dicarboxylic acid compounds.

[0053] The pKa values ​​(*1 to *3) of the fluorine-containing alcohol (A1) described above are values ​​obtained by the following measurement methods (*1), literature values ​​(*2), or estimation methods (*3).

[0054] *1: The pKa of a fluorine-containing alcohol (A1) with a high degree of acid dissociation (high acid strength) is determined as follows: The pKa of the acid dissociation of fluorine-containing alcohol (A1) in an aqueous solution is measured at 25°C. HA (fluorine-containing alcohol (A1)) + S (water) → HS ＋ (Conjugate acid of water) + A － (Conjugate base of fluorine-containing alcohol (A1)) The equilibrium constant is given by the following equation: Ka = [HS ＋ ][A － ] / [HA][S] Here, assuming a dilute aqueous solution, [S] can be approximated as 1. Ka = [HS ＋ ][A － ] / [HA] pKa=log[HA] / [HS ＋ ][A － ] = -log[HS ＋ ]-log[A － ] / [HA] is the degree of acid dissociation in aqueous solution, so -log[HS ＋ pKa = pH - log[A] is equal to pH. － ] / [HA] In a partially neutralized state, [A －Since ] = [HA], pH can be approximated as pH = pKa. Based on the above considerations, the pKa of the highly acidic fluorine-containing alcohol (A1) is measured using a potentiometric titrator.

[0055] *2: J. Amer. Chem. Soc., 96, 6851 (1974); J. Org. Chem., 32, 1217 (1967) *3: Estimated value (estimated from the difference in stretching frequencies (Δλ) between hydrogen-bonded OH and non-hydrogen-bonded OH based on the following literature) J. Org. Chem., 32, 1217 (1967); J. Amer. Chem. Soc., 86, 4948 (1964)

[0056] Methods for obtaining dicarboxylic acid compounds by a reaction using a fluorine-containing alcohol (A1) as a starting material include the following methods (α) to (γ), and method (γ) is preferred due to its high yield.

[0057] (α): A method for obtaining a dicarboxylic acid compound by transesterification reaction of compound (7) with a fluorine-containing alcohol (A1) in the presence of a catalyst.

[0058]

[0059] However, Ar is a divalent aromatic hydrocarbon group or a divalent aromatic heterocyclic group, and R ９ is an alkyl or aryl group having 1 to 10 carbon atoms. The alkyl group may be branched and may contain an etheric oxygen atom. Also, two R ９ They may be the same or different.

[0060] (β): A method for obtaining a dicarboxylic acid compound by reacting compound (8) with a fluorine-containing alcohol (A1) in the presence of a catalyst.

[0061]

[0062] However, Ar is a divalent aromatic hydrocarbon group or a divalent aromatic heterocyclic group, X １１ ~X １３ Each is independently either a hydrogen atom or a halogen atom, and X １１ ~X １３ At least one of them is a halogen atom, X １４ ~X１６ Each is independently either a hydrogen atom or a halogen atom, and X １４ ~X １６ At least one of them is a halogen atom. １１ ~X １６ Preferably, all halogen atoms are preferred, fluorine atoms or chlorine atoms are more preferred, and since industrially useful chloroform can be produced as a by-product, all chlorine atoms are most preferred.

[0063] (γ): A method for obtaining a dicarboxylic acid compound by reacting compound (9) with a fluorine-containing alcohol (A1).

[0064]

[0065] However, Ar is a divalent aromatic hydrocarbon group or a divalent aromatic heterocyclic group, and Z is a halogen atom. The two Zs may be the same or different.

[0066] Examples of catalysts used in method (α) include known transesterification catalysts. Examples of catalysts used in method (β) include alkali metals, alkaline earth metals; alkali metal hydrides, alkaline earth metal hydrides; alkali metal hydroxides, alkaline earth metal hydroxides; phase transfer catalysts; alkali metal halides, alkaline earth metal halides, ammonia halides; ion exchange resins; compounds or oxides of at least one metal selected from the group consisting of Sn, Ti, Al, W, Mo, Zr, and Zn; transesterification catalysts, etc.

[0067] In method (γ), if Z is a fluorine atom or a chlorine atom, the reaction proceeds without a catalyst, and the target product is obtained by removing the generated hydrogen halide from the system by bubbling an inert gas or heating.

[0068] In method (γ), the ratio of moles of fluorinated alcohol (A1) in the first charge to moles of compound (9) in the first charge (fluorinated alcohol (A1) / compound (9)) is preferably greater than 2, more preferably 2.5 or greater, and particularly preferably 3 or greater, from the viewpoint of improving the yield of the dicarboxylic acid compound. There is no particular upper limit to the fluorinated alcohol (A1) / compound (9) ratio, but for example it is 10 or less.

[0069] In method (γ), a solvent may be used to adjust the viscosity of the reaction system or the amount of heat generated. However, considering the volumetric efficiency of the reactor and the loss of the target product during the solvent separation step, it is preferable to carry out the reaction without a solvent if possible. The reaction temperature in method (γ) is preferably 40 to 200°C. The reaction pressure in method (γ) is usually atmospheric pressure.

[0070] <Diol Compounds> Examples of diol compounds include aliphatic diol compounds and aromatic diol compounds. Aliphatic diol compounds are preferred in terms of their excellent UV resistance and solubility in solvents. Aromatic diol compounds are preferred in that they yield industrially useful polyarylates.

[0071] As for aliphatic diol compounds, those having 2 to 12 carbon atoms are preferred from the viewpoint of heat resistance, chemical resistance, and mechanical properties of polyester. Specific examples of aliphatic diol compounds include ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, 3-chloro-1,2-propanediol, 2-chloro-1,3-propanediol, cyclohexanediol, 1,2-propylene glycol, dipropylene glycol, tripropylene glycol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,4-butenediol, 2-methyl-2,4-pentanediol (hexylene glycol), 3-methyl-1,5-pentanediol, 1,5-pentanediol, 1,6-hexanediol, isosorbide, isomannide, isoidide, 1,4-cyclohexanedimethanol, 4,4'-bicyclohexanol, adamantanediol, and fluorine-containing diols (such as 3,3,3-trifluoro-1,2-propanediol).

[0072] Among aliphatic diol compounds, alicyclic diol compounds are preferred because the resulting resin exhibits excellent optical properties. Alicyclic diol compounds do not need to have an aromatic ring, and may or may not have an unsaturated bond. Furthermore, alicyclic diol compounds may have a fused ring or a heteroatom. Examples of alicyclic diol compounds include cyclohexanediol, isosorbide, isomannide, isoidide, 1,4-cyclohexanedimethanol, 4,4'-bicyclohexanol, and adamantanediol. Among these, isosorbide is particularly preferred due to its excellent reactivity and the heat resistance and mechanical properties of the resulting resin.

[0073] As aromatic diol compounds, those having 6 to 20 carbon atoms are preferred from the viewpoint of the heat resistance, chemical resistance, mechanical properties, and moldability of polyarylates. Specific examples of aromatic diol compounds include resorcinol, catechol, hydroquinone, 2,2-(bis(4-hydroxyphenyl)propane [also known as bisphenol A], 2,2-bis(4-hydroxyphenyl)hexafluoropropane [also known as bisphenol AF], bis(4-hydroxyphenyl)methane, 4,4'-dihydroxybiphenyl, bis(4-hydroxybiphenyl)ether, dihydroxynaphthalene, phloroglycinol, and condensates of phenols. Among these, bisphenol A is preferred from the viewpoint of the ease of obtaining raw materials and the usefulness of polyarylates.

[0074] <Condensation Catalysts> Examples of condensation catalysts include known transesterification catalysts. Specific examples of condensation catalysts include nitrogen-containing compounds, alkali metal compounds, alkaline earth metal compounds, zinc compounds, boron compounds, silicon compounds, germanium compounds, tin compounds, lead compounds, onium compounds, antimony compounds, manganese compounds, titanium compounds, zirconium compounds, and the like.

[0075] The pKa of the nitrogen-containing compound is preferably 9 to 15, more preferably 10 to 15, and even more preferably 11 to 13. If the pKa of the nitrogen-containing compound is above the lower limit, the solid-phase polymerization reaction proceeds easily in step b described later. If the pKa of the nitrogen-containing compound is below the upper limit, the discoloration of the polymer after polymerization will be reduced. The pKa of the nitrogen-containing compound is the value at 25°C, and can be determined, for example, by the same method as the pKa of the fluorine-containing alcohol (A1) obtained by the measurement method (*1) or the estimation method (*3) described above. If catalog values ​​or literature values ​​are available, the catalog values ​​or literature values ​​may be used as the pKa of the nitrogen-containing compound.

[0076] The vapor pressure of the nitrogen-containing compound is preferably 1 to 10,000 Pa (absolute pressure), more preferably 10 to 3,000 Pa (absolute pressure), and even more preferably 30 to 1,000 Pa (absolute pressure). If the vapor pressure of the nitrogen-containing compound is above the lower limit, it is more likely to volatilize when the prepolymer is heated in step b described later, so that the nitrogen-containing compound does not remain in the resulting polyester. If the vapor pressure of the nitrogen-containing compound is below the upper limit, the amount of nitrogen-containing compound remaining in the reaction field during solid-phase polymerization increases, and the reaction proceeds more easily. The vapor pressure of the nitrogen-containing compound is the value at 40°C, and is measured, for example, at 40°C using a vapor pressure measuring device. If there is a catalog value or literature value, the catalog value or literature value may be used as the vapor pressure of the nitrogen-containing compound. The boiling point of the compound is defined as the temperature at which the vapor pressure is estimated to be 101.3 kPa.

[0077] Examples of nitrogen-containing compounds include amines and quaternary ammonium salts. Specific examples of amines include tertiary amines such as triethylamine, tripropylamine, tributylamine, triisoamylamine, trihexylamine, triheptylamine, trioctylamine, tridodecylamine, diazabicycloundecene (1,8-diazabicyclo[5.4.0]undeca-7-ene: DBU), diazabicyclononene (1,5-diazabicyclo[4.3.0]nona-5-ene: DBN), 4-dimethylaminopyridine, and triethylenediamine (1,4-diazabicyclo[2.2.2]octane: DABCO); secondary amines such as diethylamine and dibutylamine; primary amines such as propylamine and butylamine; and imidazoles such as 2-methylimidazole, 2-phenylimidazole, and benzimidazole. Specific examples of quaternary ammonium salts include tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, and trimethylbenzylammonium hydroxide.

[0078] Specific examples of alkali metal compounds include alkali metal hydroxides such as sodium hydroxide, potassium hydroxide, cesium hydroxide, and lithium hydroxide; alkali metal carbonates such as sodium bicarbonate, sodium carbonate, potassium carbonate, cesium carbonate, and lithium carbonate; alkali metal organic salts such as sodium acetate, potassium acetate, cesium acetate, lithium acetate, sodium stearate, potassium stearate, cesium stearate, lithium stearate, sodium benzoate, potassium benzoate, cesium benzoate, lithium benzoate, and sodium gluconate; sodium borohydride, Examples include alkali metal borides such as sodium phenylboro, sodium phenylboro, and potassium borohydride; alkali metal phosphates such as disodium hydrogen phosphate, dipotassium hydrogen phosphate, and disodium phenylphosphate; alkali metal salts of phenols such as disodium, dipotassium, dicesium, and dilithium salts of bisphenol A, and sodium, potassium, cesium, and lithium salts of phenols; alkali metal hydrogen compounds such as lithium hydride and sodium hydride; and alkali metal alkoxides such as lithium methoxide and sodium ethoxide.

[0079] Specific examples of alkaline earth metal compounds include hydroxides of alkaline earth metals such as magnesium hydroxide, calcium hydroxide, strontium hydroxide, and barium hydroxide; carbonates of alkaline earth metals such as magnesium bicarbonate, calcium bicarbonate, strontium bicarbonate, barium bicarbonate, magnesium carbonate, calcium carbonate, strontium carbonate, and barium carbonate; organic acid salts of alkaline earth metals such as magnesium acetate, calcium acetate, strontium acetate, barium acetate, magnesium stearate, calcium stearate, and calcium benzoate; phosphates of alkaline earth metals such as magnesium phenyl phosphate; alkaline earth metal salts of phenols such as magnesium salts of phenols; hydrogen compounds of alkaline earth metals such as calcium hydride; and alkoxides of alkaline earth metals such as calcium methoxide.

[0080] Specific examples of zinc compounds include zinc oxide, zinc acetate, and zinc phenoxide. Specific examples of boron compounds include boron oxide, boric acid, sodium borate, trimethyl borate, tributyl borate, and triphenyl borate. Specific examples of silicon compounds include silicon oxide, sodium silicate, tetraalkylsilicon, tetraarylsilicon, and diphenyl-ethyl-ethoxysilicon. Specific examples of germanium compounds include germanium oxide, germanium tetrachloride, germanium ethoxide, and germanium phenoxide. Specific examples of tin compounds include tin oxide, dialkyltin oxide, dialkyltin carboxylate, tin acetate, and tin compounds bonded to alkoxy or allyloxy groups such as ethyltin tributoxide; and organotin compounds. Specific examples of lead compounds include lead oxide, lead acetate, lead carbonate, basic lead carbonate, and alkoxides or allyloxides of lead or organolead. Specific examples of onium compounds include quaternary phosphonium salts and quaternary arsonium salts. Specific examples of antimony compounds include antimony oxide and antimony acetate. Specific examples of manganese compounds include manganese acetate, manganese carbonate, and manganese borate. Specific examples of titanium compounds include titanium oxide, titanium alkoxides, or allyloxides. Specific examples of zirconium compounds include zirconium acetate, zirconium oxide, zirconium alkoxides, or allyloxides, and zirconium acetylacetone.

[0081] The condensation catalyst may be used alone or in combination of two or more types. Nitrogen-containing compounds are preferred as condensation catalysts due to their high polymerization activity and excellent applicability to solution polymerization for producing prepolymers. Among these, amines are more preferred, tertiary amines are even more preferred, DBU and DBN are particularly preferred, and DBU is most preferred, due to their tendency to volatilize when the prepolymer is heated in step b. Alkali metal compounds and alkaline earth metal compounds are preferred as condensation catalysts in terms of heat resistance, weather resistance, and color resistance of the polyester. Nitrogen-containing compounds, alkali metal compounds, and alkaline earth metal compounds are preferred as condensation catalysts, nitrogen-containing compounds and alkali metal compounds are more preferred, amines are even more preferred, tertiary amines are even more preferred, DBU and DBN are particularly preferred, and DBU is most preferred.

[0082] <Step a> Step a is a step of reacting a dicarboxylic acid compound and a diol compound in the presence of a condensation catalyst to obtain a prepolymer. In step a, for example, the dicarboxylic acid compound and the diol compound are condensed in a solvent in the presence of a condensation catalyst, and then the solvent and the by-product fluorine-containing alcohol (A2) are removed by distillation to obtain a solid prepolymer. It is preferable to dry the prepolymer at a temperature below the glass transition temperature of the prepolymer. The fluorine-containing alcohol (A2) produced as a by-product of the condensation reaction between the dicarboxylic acid compound and the diol compound depends on the fluorine-containing alkoxy terminal group, which is the terminal group of the dicarboxylic acid compound used in the condensation reaction. Since the fluorine-containing alkoxy terminal group originates from the fluorine-containing alcohol (A1) used in the production of the dicarboxylic acid compound, the same alcohol as the fluorine-containing alcohol (A1) is produced as a by-product as fluorine-containing alcohol (A2) by the condensation reaction.

[0083] The condensation reaction between a dicarboxylic acid compound and a diol compound is a transesterification reaction. Suitable solvents for the condensation reaction include acetonitrile, N,N-dimethylformamide (DMF), 1,4-dioxane, dichloromethane, chloroform, and chlorobenzene. From the viewpoint of solubility of the raw materials, acetonitrile, DMF, dichloromethane, and chlorobenzene are preferred as solvents.

[0084] The ratio of moles of dicarboxylic acid compound to moles of diol compound (dicarboxylic acid compound / diol compound) can be appropriately selected depending on the desired molecular weight of the polyester. For example, the molar ratio of dicarboxylic acid compound / diol compound is preferably 0.95 to 2, more preferably 0.95 to 1.5, even more preferably 0.95 to 1.2, and particularly preferably 1 to 1.2. If the molar ratio of dicarboxylic acid compound to diol compound is within the above range, it is easy to obtain a prepolymer having constituent units derived from the dicarboxylic acid compound at its ends. As will be described later, prepolymers having constituent units derived from the dicarboxylic acid compound at their ends are prone to solid-phase polymerization without crystallization. Furthermore, solid-phase polymerization proceeds even at temperatures below the glass transition temperature of the prepolymer.

[0085] The amount of condensation catalyst is usually 10 times the amount of the diol compound. －８ It is ~1% by mass, and in terms of polymerization rate (productivity) and the deterioration of physical properties due to catalyst residue in the polyester, 10 －７ ~10 －１ Mass percent is preferred.

[0086] The reaction temperature for the condensation reaction is preferably 40 to 200°C, more preferably 60 to 180°C, even more preferably 60 to 150°C, particularly preferably 60 to 140°C, and most preferably 70 to 125°C. The reaction time for the condensation reaction varies depending on the reaction temperature, but is, for example, 0.1 to 150 hours. If the diol compound is an aromatic diol compound, the reaction time is preferably 0.1 to 24 hours, more preferably 0.5 to 12 hours, and even more preferably 1 to 6 hours. If the diol compound is an alicyclic diol compound, the reaction time is preferably 1 to 150 hours, more preferably 10 to 120 hours, and even more preferably 30 to 100 hours.

[0087] The weight-average molecular weight of the prepolymer is preferably 500 to 15,000, more preferably 500 to 12,000, and particularly preferably 1,000 to 12,000. If the weight-average molecular weight of the prepolymer is within the above range, the prepolymer is in a powder state, and solid-phase polymerization in step b proceeds easily.

[0088] The glass transition temperature of the prepolymer is preferably 60°C or higher, more preferably 70°C or higher, and particularly preferably 80°C or higher. Furthermore, the glass transition temperature of the prepolymer is preferably 160°C or lower. If the glass transition temperature of the prepolymer is above the lower limit and below the upper limit, the prepolymer will not melt, and solid-phase polymerization in step b will proceed at a low temperature.

[0089] The molar ratio (fluorine-containing alkoxy end groups / hydroxyl groups) of the prepolymer obtained in step a, which is encapsulated by the dicarboxylic acid compound, is preferably 0.8 to 1.4, more preferably 0.9 to 1.3, and even more preferably 0.95 to 1.25. If the proportion of fluorine-containing alkoxy end groups is above the lower limit, it is possible to suppress the high concentration of hydroxyl groups at the polyester ends obtained by solid-phase polymerization in step b. If the proportion of fluorine-containing alkoxy end groups is below the upper limit, it is easier to obtain a polyester with sufficient molecular weight. In this specification, the above molar ratio at the end groups of the polymer (including the prepolymer and the high molecular weight polyester) is the ratio of the polymer １ Analysis by 1H-NMR is preferable. １ The H-NMR analysis method is as described in the examples in International Publication No. 2014 / 171367.

[0090] The prepolymer obtained in step a is usually obtained in solution because a solvent is used during manufacturing. Therefore, it is preferable to isolate the solid prepolymer by distilling off the solvent and the by-product fluorine-containing alcohol (A2). It is preferable to remove the remaining solvent and by-product fluorine-containing alcohol (A2), etc., by vacuum drying the prepolymer at a low temperature. The prepolymer may be in a state such as powder or candy. A powder state is preferable in that solid-phase polymerization in step b proceeds easily. A powdered prepolymer can be obtained, for example, by pulverizing the solid prepolymer obtained as described above. Various known methods can be used for pulverization, such as mechanical grinding or mechanical grinding under freezing conditions.

[0091] The average particle size of the powdered prepolymer is preferably 0.1 μm to 1 mm, more preferably 1 to 500 μm, and even more preferably 3 to 200 μm. If the average particle size of the prepolymer is within the above range, the powdered prepolymer can be obtained with simple operations. In addition, solid-phase polymerization in step b proceeds easily.

[0092] <Step b> Step b is a step in which the prepolymer obtained in step a is solid-phase polymerized to obtain polyester. In step b, without going through a step of crystallizing the prepolymer, the prepolymer is heated at a temperature below its melting point, and the prepolymer is solid-phase polymerized to obtain polyester while the by-product fluorine-containing alcohol (A3) is discharged from the system. The fluorine-containing alcohol (A3) produced by solid-phase polymerization depends on the fluorine-containing alkoxy terminal group, which is the terminal group of the dicarboxylic acid compound used in step a. Since the fluorine-containing alkoxy terminal group originates from the fluorine-containing alcohol (A1) used in the production of the dicarboxylic acid compound, the same alcohol as fluorine-containing alcohol (A1) is produced as fluorine-containing alcohol (A3) by solid-phase polymerization. In other words, the fluorine-containing alcohol (A1) used in the production of the dicarboxylic acid compound, the fluorine-containing alcohol (A2) produced by the condensation reaction between this dicarboxylic acid compound and the diol compound, and the fluorine-containing alcohol (A3) produced by the solid-phase polymerization of the prepolymer obtained by this condensation reaction are the same.

[0093] The solid-phase polymerization reaction of the prepolymer is a transesterification reaction. The heating temperature during solid-phase polymerization of the prepolymer is below the melting temperature of the prepolymer. By maintaining the heating temperature below the melting temperature, the reaction proceeds in the solid phase. The heating temperature is preferably 200°C or lower, and more preferably 195°C or lower. In particular, if the heating temperature is 200°C or lower, discoloration of the polyester due to heat can be suppressed. The heating temperature is preferably 40°C or higher, and more preferably 90°C or higher. If the heating temperature is above the lower limit of the above, the reaction proceeds easily and the productivity of polyester is high. The heating temperature may be 40 to 200°C, or 90 to 195°C.

[0094] As solid-phase polymerization progresses, the molecular weight and melting temperature of the prepolymer gradually increase. The temperature can be increased during solid-phase polymerization, as long as it does not exceed the melting temperature of the prepolymer during the process. For example, in step b, it is preferable to start heating at a temperature of around 40 to 110°C, gradually increase the temperature, and finally reach a temperature of 160 to 250°C. By heating the prepolymer in this way, solid-phase polymerization proceeds easily, and it becomes easier to obtain high molecular weight polyester with suppressed coloration. In addition, the productivity of polyester is high.

[0095] The heating time for solid-phase polymerization of the prepolymer is preferably 1 to 48 hours, more preferably 2 to 36 hours, even more preferably 3 to 24 hours, particularly preferably 3 to 15 hours, and most preferably 5 to 12 hours. If the heating time is within the above range, the productivity of polyester is high and it is suitable for industrial production.

[0096] Methods for discharging fluorine-containing alcohol (A3), a by-product during solid-phase polymerization, include solid-phase polymerization under reduced pressure, solid-phase polymerization while blowing in an inert gas, and methods combining these. The method of introducing an inert gas requires the reuse of the inert gas discharged from the system, resulting in a complicated process; therefore, solid-phase polymerization under reduced pressure is more preferable.

[0097] When solid-phase polymerization of a prepolymer under reduced pressure, the pressure is preferably in the high vacuum range of 13 kPa (absolute pressure) (100 torr (absolute pressure)) or less, more preferably 1.3 kPa (absolute pressure) (10 torr (absolute pressure)) or less, and particularly preferably 0.67 kPa to 0.013 kPa (absolute pressure) (5 to 0.1 torr (absolute pressure)). If the pressure is within the above range, solid-phase polymerization will proceed quickly. An inert gas refers to a gas that is inert to solid-phase polymerization, and examples include nitrogen, argon, helium, carbon dioxide, lower hydrocarbons, acetone, etc.

[0098] Known apparatuses can be used for solid-phase polymerization. The apparatus can be of any type, including batch type, continuous type, or a combination of both. Specifically, examples include tumbler type, kiln type, paddle dryer type, screw conveyor type, vibratory type, fluidized bed type, fixed bed type, and mobile bed type. For experimental use, a vacuum dryer or the like, which is used for drying polymers, may be used.

[0099] The weight-average molecular weight of the final polyester is preferably 10,000 to 200,000, more preferably 15,000 to 100,000, and particularly preferably 20,000 to 80,000. If the weight-average molecular weight of the polyester is above the lower limit, the heat resistance, rigidity, and toughness are better, and if it is below the upper limit, the moldability is better.

[0100] The number-average molecular weight of the final polyester is preferably 3,000 to 100,000, more preferably 7,000 to 50,000, and particularly preferably 10,000 to 35,000. If the number-average molecular weight of the polyester is above the lower limit, the heat resistance, rigidity, and toughness are better, and if it is below the upper limit, the moldability is better.

[0101] <Step c> Step c is a step in which the ends of the polyester obtained in step b are replaced with substituents. In step c, the ester group end of the polyester may be replaced, the hydroxyl group end may be replaced, or both ends may be replaced. The method of replacing the ends of the polyester with substituents is not particularly limited, and known methods can be used, such as known transesterification reactions.

[0102] When substituting the ester group end, it is preferable to substitute the monovalent group bonded to the terminal ester bond with the substituent (S1) or substituent (S2) shown below. Substituent (S1) is a monovalent group obtained by removing a hydroxyl group from at least one compound (s1) selected from the group consisting of phenol, cresol, p-t-butylphenol, 2,3,5-trimethylphenol, 2,3,6-trimethylphenol, and cumylphenol. Substituent (S2) is a monovalent group obtained by removing a hydroxyl group from at least one compound (s2) selected from the group consisting of methanol, ethanol, n-propanol, isopropanol, n-butanol, 2-butanol, pentanol, hexanol, dodecyl alcohol, stearyl alcohol, benzyl alcohol, and phenethyl alcohol. As a substituent, a monovalent group obtained by removing a hydroxyl group from p-t-butylphenol is preferred. In this specification, "compound (s1)" is also referred to as "monovalent phenols," and "compound (s2)" is also referred to as "monovalent alcohols."

[0103] By substituting the ester group end with a substituent (S1) or substituent (S2), a fluorine-containing alcohol (A4) is produced as a by-product. The fluorine-containing alcohol (A4) produced as a by-product depends on the fluorine-containing alkoxy end group, which is the end group of the dicarboxylic acid compound used in step a. Since the fluorine-containing alkoxy end group originates from the fluorine-containing alcohol (A1) used in the production of the dicarboxylic acid compound, the same alcohol as fluorine-containing alcohol (A1) is produced as a by-product as fluorine-containing alcohol (A4) by the substitution reaction. In other words, the fluorine-containing alcohol (A1) used in the production of the dicarboxylic acid compound, the fluorine-containing alcohol (A2) produced as a by-product by the condensation reaction between this dicarboxylic acid compound and the diol compound, the fluorine-containing alcohol (A3) produced as a by-product by the solid-phase polymerization of the prepolymer obtained by this condensation reaction, and the fluorine-containing alcohol (A4) produced as a by-product by the substitution reaction are all the same.

[0104] When substituting the hydroxyl group end, it is preferable to substitute the hydrogen atom of the terminal hydroxyl group with the substituent (S3) or substituent (S4) shown below. The substituent (S3) is a monovalent group obtained by removing a chlorine atom from at least one compound (s3) selected from the group consisting of benzoic acid chloride, methanesulfonyl chloride, and phenyl chloroformate. The substituent (S4) is a monovalent group obtained by removing OH from the carboxylic acid (COOH) of at least one compound (s4) selected from the group consisting of acetic acid, propionic acid, octanoic acid, cyclohexanecarboxylic acid, benzoic acid, toluic acid, phenylacetic acid, p-t-butylbenzoic acid, and p-methoxyphenylacetic acid. As a substituent, the monovalent group obtained by removing OH from the carboxylic acid of p-t-butylbenzoic acid is preferred. In this specification, "compound (s3)" is also referred to as "monovalent chlorides," and "compound (s4)" is also referred to as "monovalent carboxylic acid."

[0105] Substituting the hydroxyl group end with substituent (S3) produces hydrogen chloride as a by-product, and substituting it with substituent (S4) produces water as a by-product.

[0106] <Effects> In the polyester manufacturing method described above, a specific dicarboxylic acid compound and a diol compound are reacted in the presence of a condensation catalyst, and the resulting prepolymer is subjected to solid-phase polymerization. Therefore, high molecular weight polyester can be produced at a relatively low temperature below the melting temperature of the prepolymer. Furthermore, because polyester can be produced at a relatively low temperature using this manufacturing method, heat-induced discoloration of the polyester can be suppressed.

[0107] In this manufacturing method, a prepolymer having constituent units derived from the dicarboxylic acid compound at its termini is obtained by reacting a specific dicarboxylic acid compound with a diol compound. Prepolymers having constituent units derived from the dicarboxylic acid compound at their termini are thought to undergo solid-phase polymerization, which is a transesterification reaction, even at relatively low temperatures below the melting temperature of the prepolymer (for example, temperatures below 200°C), because the constituent units derived from the dicarboxylic acid compound at the termini have high affinity with other prepolymers and readily undergo transesterification. On the other hand, prepolymers obtained by reacting a diol compound with a dicarboxylic acid other than the specific dicarboxylic acid compound are thought to undergo solid-phase polymerization unless the temperature is increased (for example, above 240°C), because the constituent units derived from the dicarboxylic acid at the termini have low affinity with other prepolymers and readily undergo transesterification.

[0108] Furthermore, the dicarboxylic acid compound in this invention exhibits a high degree of dissociation of the ester moiety due to the electron-withdrawing effect of the fluorine atom, facilitating condensation reactions with diol compounds. In addition, the by-products, fluorine-containing alcohols (A2) and (A3), have low boiling points and can be rapidly removed from the reaction system, thus accelerating the rate of the equilibrium transesterification reaction. Therefore, the polyester production method of this invention solves the problems of conventional transesterification methods, such as the difficulty in obtaining high molecular weight products and discoloration caused by long reaction times at high temperatures.

[0109] [Polymers] A polymer according to one aspect of the present invention is a polyester represented by any of the following formulas (P1), (P2), and (P3). Hereinafter, the polyester represented by formula (P1) will also be called "polymer (P1)", the polyester represented by formula (P2) will also be called "polymer (P2)", and the polyester represented by formula (P3) will also be called "polymer (P3)".

[0110]

[0111] However, G1 is a monovalent group represented by the following formula (g1), a monovalent group represented by the following formula (g2), or a hydrogen atom, G2 is a hydrogen atom, Ar is a divalent aromatic hydrocarbon group or a divalent aromatic heterocyclic group, X ４ m is a divalent group derived from an alicyclic diol compound, and m is an integer between 10 and 1000.

[0112]

[0113] However, R １ CX １ Y １ R ４ It is a group represented by R ２ is a hydrogen atom or CX ２ Y ２ R ５ It is a group represented by R ３ is a hydrogen atom or CX ３ Y ３ R ６ It is a group represented by R ７ X is a perfluoroalkylene group having 1 to 5 carbon atoms (however, it may also contain an etheric oxygen atom), and １ ~X ３ Each is independently a hydrogen atom, a fluorine atom, or R ｆ Y １ ~Y ３ Each of these is independently a fluorine atom or R ｆ And R ４ ~R ６ Each of these is an independent fluorine atom, R ｆ , OR ｆ Or an alkyl group having 1 to 6 carbon atoms, R ｆ These are independently fluoroalkyl groups having 1 to 4 carbon atoms or fluoroalkyl groups having 2 to 4 carbon atoms and an etheric oxygen atom.

[0114] The Ar in formulas (P1) to (P3) is the same as the Ar in formulas (1) to (3) described above. The divalent group derived from the alicyclic diol compound in formulas (P1) to (P3) is the divalent group obtained by removing a hydrogen atom from the two hydroxyl groups of the alicyclic diol compound exemplified in the description of the diol compound above.

[0115] R in equation (g1)１ ~R ３ These are R in equations (1) and (2) described above. １ ~R ３ It is the same as R in equation (g2). ７ This is R in equation (3) above. ７ It is the same as this.

[0116] Polymers (P1) to (P3) are obtained, for example, through steps a and b described above. After step b, step c may be performed as needed. Polymers (P1) to (P3) obtained through step c are polyesters in which at least one of G1 in formulas (P1) and (P3), and G2 in formulas (P1) and (P2) is substituted with a substituent. When G1 in formulas (P1) and (P3) is substituted, G1 is preferably substituted with the substituent (S1) or substituent (S2) described above, and more preferably substituted with a monovalent group obtained by removing a hydroxyl group from p-t-butylphenol. When G2, which corresponds to the hydrogen atom of the hydroxyl group in formulas (P1) and (P2), is substituted, G2 is preferably substituted with the substituent (S3) or substituent (S4) described above, and more preferably substituted with a monovalent group obtained by removing the OH from the carboxylic acid of p-t-butylbenzoic acid.

[0117] The weight-average molecular weights of polymers (P1) to (P3) are preferably 10,000 to 200,000, more preferably 15,000 to 100,000, and particularly preferably 20,000 to 80,000. If the weight-average molecular weights of polymers (P1) to (P3) are above the lower limit, the heat resistance, rigidity, and toughness are better, and if they are below the upper limit, the moldability is better.

[0118] The number average molecular weights of polymers (P1) to (P3) are preferably 3,000 to 100,000, more preferably 7,000 to 50,000, and particularly preferably 10,000 to 35,000. If the number average molecular weights of polymers (P1) to (P3) are above the lower limit, the heat resistance, rigidity, and toughness are better, and if they are below the upper limit, the moldability is better.

[0119] The present invention will be described in detail below with reference to examples, but the present invention is not limited to the following examples as long as it does not exceed the spirit of the invention, and various modifications are possible as long as they do not depart from the spirit of the invention. Examples 1, 2, 3, 5, 6, and 7 are examples, and Example 4 is a comparative example.

[0120] (Gas Chromatography Mass (GC-Mass) Analysis) GC-Mass analysis was performed using the following equipment under the following conditions: • Equipment: Shimadzu Corporation, GC-17A / QP-5050A system; • Detection method: EI detection.

[0121] (NMR Analysis) NMR analysis was performed using the following equipment under the following conditions: • Equipment: JEOL Ltd., AL300, １ ¹H-NMR (300.4 MHz, solvent: CDCl) ３ , Standard: TMS), ・ １９ F-NMR (282.65 MHz, solvent: CDCl) ３ Standard: CFCl ３ ).

[0122] (Gel Permeation Chromatography (GPC) Analysis) The weight-average molecular weight and number-average molecular weight of the synthesized prepolymer and polyester were determined by analyzing them using the following apparatus under the following conditions and converting them to the standard material polystyrene. Apparatus: Tosoh Corporation, HLC-8220GPC; Guard column: TSKguardcolumn SuperMPHZ-M; Columns: TSKgel SuperMultiporeHZ-M (3 tubes); Mobile phase: Tetrahydrofuran; Flow rate: 0.35 mL / min; Detection method: RI detection; Column temperature: 40°C.

[0123] (Synthesis Example 1) Synthesis of bis(1,1,1,3,3,3-hexafluoropropyl) isophthalate (compound (1-1)): In a 300 mL glass reactor equipped with a stirrer and dropping funnel, 14.6 g (86.7 mmol) of 1,1,1,3,3,3-hexafluoro-2-propanol (compound (5-1), pKa: 9.4), 9.57 g (94.6 mmol) of triethylamine, and 70 mL of anhydrous dichloromethane were charged. Then, while stirring at 0°C, 8.00 g (39.4 mmol) of isophthaloyl chloride (compound (9-1)) dissolved in 70 mL of anhydrous dichloromethane was added dropwise, adjusting the rate while observing the rise in internal temperature (ΔT) and the generation of hydrogen chloride gas. After the addition was complete, the mixture was stirred overnight at room temperature. After the reaction was complete, a portion of the crude solution was taken. １ 1H-NMR analysis was performed. The results confirmed that compound (1-1) was formed as the main product. Compound (1-1) was obtained in 87% yield.

[0124]

[0125] Regarding the product compound (1-1), １ The structure was assigned by 1H-NMR analysis. Compound (1-1) １ The H-NMR results are shown below. １ H-NMR δ: 6.707-6.799 (2H, m), 7.952 (1H, t, J = 7.9Hz), 8.527 (2H, dd, J = 7.9, 1.8Hz), 8.777 (1H, td, J = 1.8, 0.5Hz).

[0126] (Synthesis Example 2) Synthesis of bis(1,1,1,3,3,3-hexafluoropropyl) terephthalate (compound (1-2)): In a 300 mL glass reactor equipped with a stirrer and a dropping funnel, 14.6 g (86.7 mmol) of 1,1,1,3,3,3-hexafluoro-2-propanol (compound (5-1), pKa: 9.4), 9.57 g (94.6 mmol) of triethylamine, and 70 mL of anhydrous dichloromethane were charged. Then, while stirring at 0°C, 8.00 g (39.4 mmol) of terephthaloyl chloride (compound (9-2)) dissolved in 70 mL of anhydrous dichloromethane was added dropwise, adjusting the rate while observing the rise in internal temperature (ΔT) and the generation of hydrogen chloride gas. After the addition was complete, the mixture was stirred overnight at room temperature. After the reaction was complete, a portion of the crude solution was taken. １ 1H-NMR analysis was performed. The results confirmed that compound (1-2) was formed as the main product. Compound (1-2) was obtained in 93% yield.

[0127]

[0128] Regarding the product compounds (1-2), １ The structure was assigned by 1H-NMR analysis. Compounds (1-2) １ The H-NMR results are shown below. １ H-NMR δ: 6.708-6.800 (2H, m), 8.383 (4H, s).

[0129] (Synthesis Example 3) Synthesis of bis(2,2,3,3-tetrafluoropropyl) isophthalate (compound (1-3)): 500 g (2.46 mol) of isophthaloyl chloride (compound (9-1)) was charged into a 2000 mL glass reactor equipped with a thermometer, stirrer, reflux condenser, and dropping funnel, and the temperature was raised to 100°C while stirring. Next, 715.53 g (5.41 mol) of 2,2,3,3-tetrafluoro-1-propanol (compound (5-2), pKa: 12.7) was added dropwise, adjusting the rate while observing the rise in internal temperature (ΔT) and the generation of hydrogen chloride gas. After the addition was complete, the mixture was stirred at 100°C for 1 hour, and then the temperature was raised to 140°C while observing the generation of hydrogen chloride gas, and the mixture was heated for a total of 9 hours. After the reaction was complete, the crude solution was cooled to room temperature, and a portion of the crude solution was taken and analyzed by 1H-NMR. The results confirmed that compound (1-3) was formed as the main product (41.8% yield based on compound (5-2)). Compound (1-3) was obtained in a yield of 93.5%.

[0130]

[0131] Regarding the product compounds (1-3), １ In addition to H-NMR analysis, １９ Structural assignment was performed by F-NMR analysis and GC-Mass analysis. Compounds (1-3) １ H-NMR, １９ The results of F-NMR and Mass fragment analysis are shown below. １ H-NMR δ: 4.762 (4H, t, J = 12.6Hz), 5.962 (2H, tt, J = 3.3, 52.9Hz), 7.617 (1H , t, J=7.8Hz), 8.297 (2H, dd, J=1.8, 7.8Hz), 8.711 (1H, t, J=1.5Hz). １９ F-NMR δ: -137.142 (4F, d, 53.1Hz), -123.257 (4F, tdt, J = 1.7, 3.3, 12.2Hz). MS m / z: 235 (PhC(=O)OCH ２ CF ２ CF ２H);263(C(=O)PhC(=O)OCH2CF2CF2H);343(CF2CH2OC(=O)PhC(=O)OCH ２ CF ２ CF ２ H); 394 (CF ２ HCF ２ CH ２ OC(=O)PhC(=O)OCH ２ CF ２ CF ２ H).

[0132] (Synthesis Example 4) Synthesis of bis(2,2,3,3-tetrafluoropropyl)terephthalate (compound (1-4)): 857.21 g (4.22 mol) of terephthaloyl chloride (compound (9-2)) was charged into a 3000 mL glass reactor equipped with a stirrer, reflux condenser, and dropping funnel, and the temperature was raised to 100°C while stirring. Next, 1248.84 g (9.46 mol) of 2,2,3,3-tetrafluoropropanol (compound (5-2)) was added dropwise, adjusting the rate while monitoring the rise in internal temperature (ΔT) and the generation of hydrogen chloride gas. After the addition was complete, the mixture was stirred at 100°C for 1 hour, and then the temperature was raised to 140°C while monitoring the generation of hydrogen chloride gas, and the mixture was heated for a total of 9 hours. After the reaction was complete, the crude solution was cooled to room temperature, and a portion of the crude solution was taken and subjected to 1H-NMR analysis. As a result, it was confirmed that compound (1-4) was formed as the main product (43.1% yield based on compound (5-2)). The product, compound (1-4), was obtained in 96.7% yield.

[0133]

[0134] Regarding the product compounds (1-4), １ In addition to H-NMR analysis, １９ The structure of compounds (1-4) was determined by F-NMR analysis and GC-Mass analysis. １ H-NMR, １９ The results of F-NMR and Mass fragment analysis are shown below. １ H-NMR δ: 4.760 (4H, tt, J = 1.2, 12.9Hz), 5.947 (2H, tt, J = 3.3, 53.2Hz), 8.154 (4H, s). １９F-NMR δ: -137.020 (4F, d, 52.9Hz), -123.203 (4F, tdt, J = 13.0, 3.4, 1.7Hz). MS m / z: 235 (PhC(=O)OCH ２ CF ２ CF ２ H);263(C(=O)PhC(=O)OCH ２ CF ２ CF ２ H); 343 (CF ２ CH ２ OC(=O)PhC(=O)OCH ２ CF ２ CF ２ H); 394 (CF ２ HCF ２ CH ２ OC(=O)PhC(=O)OCH ２ CF ２ CF ２ H).

[0135] (Example 1) Synthesis of polyarylate 1: A stirrer tip was placed in a 5 mL pressure-resistant glass container, and 0.225 g (0.986 mmol) of bisphenol A (compound (10)), 0.361 g (0.775 mmol) of compound (1-1), and 0.120 g (0.258 mmol) of compound (1-2) were added. Vacuum degassing was performed for 3 hours. Under a nitrogen atmosphere, 2.4 mL of dichloromethane and 7.2 mg (0.047 mmol) of diazabicycloundecene (DBU, pKa: 12.5, vapor pressure: 707 Pa (absolute pressure)) were added, the container was sealed, and then immersed in an oil bath. The mixture was heated in the oil bath at 75°C for 3 hours while stirring at 200 rpm, resulting in a homogeneous, colorless, and transparent solution. The resulting colorless, transparent solution was degassed under vacuum at less than 300 Pa for 1 hour to remove the solvent, dichloromethane, and the by-product, fluorine-containing alcohol (A2), to obtain a white, solid prepolymer. The fluorine-containing alcohol (A2) was 1,1,3,3,3-hexafluoro-2-propanol. The weight-average molecular weight (Mw) of the obtained prepolymer was 5,000, and the number-average molecular weight (Mn) was 2,400.

[0136]

[0137] The obtained prepolymer was heated in an oil bath at 40°C, 60°C, 80°C, 100°C, and 120°C for 1 hour each, and then heated at 140°C, 160°C, and 180°C for 2 hours each to complete solid-phase polymerization and obtain a polyarylate represented by the following formula (P-1). During solid-phase polymerization, the pressure in the reaction vessel was maintained at less than 300 Pa in all steps, and the temperature in the reaction system was maintained below the melting temperature of the prepolymer. In addition, the by-product fluorine-containing alcohol (A3) was discharged from outside the reaction system during solid-phase polymerization. The fluorine-containing alcohol (A3) was 1,1,3,3,3-hexafluoro-2-propanol. The obtained polyarylate was dissolved in cresol, and the molecular weight was measured by GPC using DMF containing 30 mmol / L lithium bromide and 60 mmol / L phosphoric acid as the developing solvent. When polystyrene was used as the calibration curve, the mass-average molecular weight (Mw) was 48,948, the number-average molecular weight (Mn) was 11,793, and the degree of dispersion (Mw / Mn) was 4.151. The results are shown in Table 1.

[0138]

[0139] (Example 2) Synthesis of polyarylate 2: A stirrer tip was placed in a 5 mL pressure-resistant glass container, and 0.214 g (0.937 mmol) of bisphenol A (compound (10)), 0.344 g (0.738 mmol) of compound (1-1), and 0.114 g (0.245 mmol) of compound (1-2) were added, and vacuum degassing was performed for 3 hours. Under a nitrogen atmosphere, 1.7 mL of dichloromethane and 7.0 mg (0.046 mmol) of diazabicycloundecene (DBU, pKa: 12.5, vapor pressure: 707 Pa (absolute pressure)) were added, the container was sealed, and then immersed in an oil bath. The mixture was heated in the oil bath at 75°C for 3 hours while stirring at 200 rpm, resulting in a homogeneous, colorless, and transparent solution. The resulting colorless, transparent solution was degassed under vacuum at less than 300 Pa for 1 hour to remove the solvent, dichloromethane, and the fluorinated alcohol (A2), yielding a white, solid prepolymer. The fluorinated alcohol (A2) was 1,1,3,3,3-hexafluoro-2-propanol. The weight-average molecular weight (Mn) of the obtained prepolymer was 6,300, and the number-average molecular weight (Mn) was 3,300.

[0140] The obtained prepolymer was heated in an oil bath at 40°C, 60°C, 80°C, 100°C, and 120°C for 1 hour each, and then heated at 140°C, 160°C, and 180°C for 2 hours each to complete solid-phase polymerization and obtain polyarylate. During solid-phase polymerization, the pressure in the reaction vessel was maintained below 300 Pa in all steps, and the temperature in the reaction system was maintained below the melting temperature of the prepolymer. In addition, the by-product fluorine-containing alcohol (A3) was discharged from the reaction system during solid-phase polymerization. The fluorine-containing alcohol (A3) was 1,1,3,3,3-hexafluoro-2-propanol. The obtained polyarylate was dissolved in cresol, and the molecular weight was measured by GPC using DMF containing 30 mmol / L lithium bromide and 60 mmol / L phosphoric acid as the developing solvent. When polystyrene was used as the calibration curve, the mass-average molecular weight (Mw) was 48,084, the number-average molecular weight (Mn) was 16,698, and the degree of dispersion (Mw / Mn) was 2.880. The results are shown in Table 1.

[0141] (Example 3) Synthesis of polyarylate 3: A stirrer tip was placed in a 5 mL pressure-resistant glass container, and 0.273 g (1.866 mmol) of isosorbide (compound (11)), 0.657 g (1.410 mmol) of compound (1-1), and 0.212 g (0.456 mmol) of compound (1-2) were added, and vacuum degassing was performed for 3 hours. Under a nitrogen atmosphere, 2.1 mL of acetonitrile and 14.0 mg (0.092 mmol) of diazabicycloundecene (DBU, pKa: 12.5, vapor pressure: 707 Pa (absolute pressure)) were added, the container was sealed, and then immersed in an oil bath. The mixture was heated in the oil bath at 120°C for 70 hours while stirring at 200 rpm, and a precipitate was obtained. The solution containing the precipitate was degassed under vacuum at less than 300 Pa for 1 hour to remove the solvent, acetonitrile, and the by-product, fluorinated alcohol (A2). The precipitate was then dissolved in dichloromethane, and the resulting solution was again degassed under vacuum at less than 300 Pa for 1 hour to remove the dichloromethane, yielding a white solid prepolymer. The fluorinated alcohol (A2) was 1,1,3,3,3-hexafluoro-2-propanol. The weight-average molecular weight (Mw) of the obtained prepolymer was 8,412, and the number-average molecular weight (Mn) was 4,233.

[0142]

[0143] The obtained prepolymer was heated in an oil bath at 40°C, 60°C, 80°C, 100°C, and 120°C for 1 hour each, and then heated at 140°C, 160°C, and 180°C for 2 hours each to complete solid-phase polymerization and obtain a polyarylate represented by the following formula (P-2). During solid-phase polymerization, the pressure in the reaction vessel was maintained at less than 300 Pa in all steps, and the temperature in the reaction system was maintained below the melting temperature of the prepolymer. In addition, the by-product fluorine-containing alcohol (A3) was discharged from outside the reaction system during solid-phase polymerization. The fluorine-containing alcohol (A3) was 1,1,3,3,3-hexafluoro-2-propanol. The obtained polyarylate was dissolved in cresol, and the molecular weight was measured by GPC using DMF containing 30 mmol / L lithium bromide and 60 mmol / L phosphoric acid as the developing solvent. When polystyrene was used as the calibration curve, the mass-average molecular weight (Mw) was 36,185, the number-average molecular weight (Mn) was 16,583, and the degree of dispersion (Mw / Mn) was 2.182. The obtained polyarylate was colorless and was found to be of high purity. The results are shown in Table 1.

[0144]

[0145] (Example 4) Synthesis of polyarylate 4: In a 300 mL melt polymerization reactor, 20.99 g (0.092 mol) of bisphenol A (compound (10)), 27.20 g (0.069 mol) of compound (1-3), 9.07 g (0.023 mol) of compound (1-4), and 0.0027 g (0.5 × 10) of potassium borohydride were added. －４ A mol (mol) was added. The following deoxygenation process was repeated three times. Deoxygenation process: Oxygen was removed by evacuating the reactor at 0°C until the temperature was approximately 1 tor, and then nitrogen was refilled into the reactor to atmospheric pressure.

[0146] The reactor was immersed in an oil bath preheated to 200°C. Stirring was carried out at an oil bath temperature of 200°C and a stirring speed of 200 rpm. After 10 minutes, thermal equilibrium was reached, the solids completely melted, and a colorless, homogeneous liquid was obtained. Subsequently, the reaction was continued for 5 minutes while maintaining the reactor pressure at 740 Torrell and the reactor temperature at 230°C. At this point, compound (5-2) began to be evacuated from the reaction vessel and distilled into a receiving flask. After 60 minutes, the reactor temperature was raised to 250°C and the reactor pressure was maintained at 300 Torrell. After another 60 minutes, the reactor temperature was raised to 270°C and the reactor pressure was maintained at 10 Torrell. After another 60 minutes, the reactor temperature was raised to 280°C and the reactor pressure was maintained at 1 Torrell. After 30 minutes, the polymerization was completed by cooling to room temperature, yielding polyarylate.

[0147] GPC analysis of the obtained polyarylate revealed a mass-average molecular weight (Mw) of 13,962, a number-average molecular weight (Mn) of 9,215, and a dispersion degree (Mw / Mn) of 1.515. The obtained polyarylate was colorless and was found to be of high purity. The results are shown in Table 1.

[0148] (Example 5) Synthesis of polyarylate 5: A stirrer tip was placed in a 5 mL pressure-resistant glass container, and 0.329 g (2.249 mmol) of isosorbide (compound (11)) and 1.046 g (2.249 mmol) of compound (1-2) were added. Vacuum degassing was performed for 3 hours. Under a nitrogen atmosphere, 2.1 mL of acetonitrile and 14.0 mg (0.092 mmol) of diazabicycloundecene (DBU, pKa: 12.5, vapor pressure: 707 Pa (absolute pressure)) were added, the container was sealed, and then immersed in an oil bath. The mixture was heated in the oil bath at 120°C for 70 hours with stirring at 200 rpm, and a precipitate was obtained. The solution containing the precipitate was vacuum degassed at less than 300 Pa for 1 hour, and the solvent acetonitrile and the by-product fluorine-containing alcohol (A2) were removed by distillation. Subsequently, the precipitate was dissolved in dichloromethane, and the resulting solution was again degassed under vacuum at less than 300 Pa for 1 hour to remove the solvent, dichloromethane, and a white solid prepolymer was obtained. The fluorine-containing alcohol (A2) was 1,1,3,3,3-hexafluoro-2-propanol. The weight-average molecular weight (Mw) of the obtained prepolymer was 4,628, and the number-average molecular weight (Mn) was 3,066.

[0149] The obtained prepolymer was heated in an oil bath at 40°C, 60°C, 80°C, 100°C, and 120°C for 1 hour each, and then heated at 140°C, 160°C, and 180°C for 2 hours each to complete solid-phase polymerization and obtain a polyarylate represented by the following formula (P-2). During solid-phase polymerization, the pressure in the reaction vessel was maintained at less than 300 Pa in all steps, and the temperature in the reaction system was maintained below the melting temperature of the prepolymer. In addition, the by-product fluorine-containing alcohol (A3) was discharged from outside the reaction system during solid-phase polymerization. The fluorine-containing alcohol (A3) was 1,1,3,3,3-hexafluoro-2-propanol. The obtained polyarylate was dissolved in cresol, and the molecular weight was measured by GPC using DMF containing 30 mmol / L lithium bromide and 60 mmol / L phosphoric acid as the developing solvent. When polystyrene was used as the calibration curve, the mass-average molecular weight (Mw) was 21,841, the number-average molecular weight (Mn) was 10,799, and the degree of dispersion (Mw / Mn) was 2.023. The obtained polyarylate was colorless and was found to be of high purity. The results are shown in Table 2.

[0150] (Example 6) Synthesis of polyarylate 6: A stirrer tip was placed in a 5 mL pressure-resistant glass container, and 0.311 g (2.126 mmol) of isomannide (compound (12)) and 0.989 g (2.126 mmol) of compound (1-2) were added. Vacuum degassing was performed for 3 hours. Under a nitrogen atmosphere, 1.7 mL of dichloromethane and 16.2 mg (0.107 mmol) of diazabicycloundecene (DBU, pKa: 12.5, vapor pressure: 707 Pa (absolute pressure)) were added, the container was sealed, and then immersed in an oil bath. The mixture was heated in the oil bath at 75°C for 3 hours with stirring at 200 rpm, resulting in a homogeneous, colorless, transparent solution. The obtained colorless, transparent solution was vacuum degassed at less than 300 Pa for 1 hour to remove the solvent dichloromethane and fluorine-containing alcohol (A2), obtaining a white solid prepolymer. The fluorine-containing alcohol (A2) was 1,1,3,3,3-hexafluoro-2-propanol. The weight-average molecular weight (Mn) of the obtained prepolymer was 3,659, and the number-average molecular weight (Mn) was 2,290.

[0151] The obtained prepolymer was heated in an oil bath at 40°C, 60°C, 80°C, 100°C, and 120°C for 1 hour each, and then heated at 140°C, 160°C, and 180°C for 2 hours each to complete solid-phase polymerization and obtain polyarylate. During solid-phase polymerization, the pressure in the reaction vessel was maintained below 300 Pa in all steps, and the temperature in the reaction system was maintained below the melting temperature of the prepolymer. In addition, the by-product fluorine-containing alcohol (A3) was discharged from the reaction system during solid-phase polymerization. The fluorine-containing alcohol (A3) was 1,1,3,3,3-hexafluoro-2-propanol. The obtained polyarylate was dissolved in cresol, and the molecular weight was measured by GPC using DMF containing 30 mmol / L lithium bromide and 60 mmol / L phosphoric acid as the developing solvent. When polystyrene was used as the calibration curve, the mass-average molecular weight (Mw) was 19,152, the number-average molecular weight (Mn) was 9,203, and the degree of dispersion (Mw / Mn) was 2.081. The results are shown in Table 2.

[0152] (Example 7) Synthesis of polyarylate 7: A stirrer tip was placed in a 5 mL pressure-resistant glass container, and 0.254 g (1.112 mmol) of bisphenol A (compound (10)), 0.408 g (0.876 mmol) of compound (1-1), and 0.135 g (0.291 mmol) of compound (1-2) were added, and vacuum degassing was performed for 3 hours. Under a nitrogen atmosphere, 1.7 mL of dichloromethane and 7.4 mg (0.060 mmol) of diazabicyclononene (1,5-diazabicyclo[4.3.0]nona-5-ene (DBN, pKa: 12.7, vapor pressure: 284 Pa (absolute pressure)) were added to a container, which was then sealed and immersed in an oil bath. The mixture was heated in the oil bath at 75°C for 3 hours with stirring at 200 rpm, resulting in a homogeneous, colorless, and transparent solution. The obtained colorless and transparent solution was degassed under vacuum at less than 300 Pa for 1 hour to remove the solvent, dichloromethane, and the fluorine-containing alcohol (A2), obtaining a white solid prepolymer. The fluorine-containing alcohol (A2) was 1,1,3,3,3-hexafluoro-2-propanol. The weight-average molecular weight (Mn) of the obtained prepolymer was 1,341, and the number-average molecular weight (Mn) was 1,011.

[0153] The obtained prepolymer was heated in an oil bath at 40°C, 60°C, 80°C, 100°C, and 120°C for 1 hour each, and then heated at 140°C, 160°C, and 180°C for 2 hours each to complete solid-phase polymerization and obtain polyarylate. During solid-phase polymerization, the pressure in the reaction vessel was maintained below 300 Pa in all steps, and the temperature in the reaction system was maintained below the melting temperature of the prepolymer. In addition, the by-product fluorine-containing alcohol (A3) was discharged from the reaction system during solid-phase polymerization. The fluorine-containing alcohol (A3) was 1,1,3,3,3-hexafluoro-2-propanol. The obtained polyarylate was dissolved in cresol, and the molecular weight was measured by GPC using DMF containing 30 mmol / L lithium bromide and 60 mmol / L phosphoric acid as the developing solvent. When polystyrene was used as the calibration curve, the mass-average molecular weight (Mw) was 23,318, the number-average molecular weight (Mn) was 10,516, and the degree of dispersion (Mw / Mn) was 2.217. The results are shown in Table 2.

[0154]

[0155]

[0156] Examples 1-3 and 5-7 allowed for the synthesis of polyarylates with higher molecular weights at lower polymerization temperatures compared to Example 4.

[0157] The polyester obtained by the manufacturing method of the present invention is useful as a material for fibers, films, containers, etc., and polyarylate in particular is useful as an engineering plastic. The entire contents of the specification, claims, and abstract of Japanese Patent Application No. 2024-174445, filed on October 3, 2024, are incorporated herein by reference as disclosure of the specification of the present invention.

Claims

1. A method for producing a polyester, comprising reacting at least one dicarboxylic acid compound selected from the group consisting of a compound represented by the following formula (1), a compound represented by the following formula (2), and a compound represented by the following formula (3) with a diol compound in the presence of a condensation catalyst, heating the obtained prepolymer at a temperature below its melting temperature, and subjecting the prepolymer to solid-phase polymerization while discharging the by-produced fluorine-containing alcohol (A3) out of the system. However, Ar is a divalent aromatic hydrocarbon group or a divalent aromatic heterocyclic group, and R １ is a group represented by CX １ Y １ R ４ Two Rs １ may be the same or different, and R ２ is a hydrogen atom or a group represented by CX ２ Y ２ R ５ Two Rs ２ may be the same or different, and R ３ is a hydrogen atom or a group represented by CX ３ Y ３ S R ６ Two Rs ３ may be the same or different, and X １ to X ３ are each independently a hydrogen atom, a fluorine atom or R ｆ and Y １ to Y ３ are each independently a fluorine atom or R ｆ and R ４ to R ６ are each independently a fluorine atom, R ｆ OR ｆ or an alkyl group having 1 to 6 carbon atoms, and R ｆ is independently a fluoroalkyl group having 1 to 4 carbon atoms or a fluoroalkyl group having an etheric oxygen atom having 2 to 4 carbon atoms. However, Ar is a divalent aromatic hydrocarbon group or a divalent aromatic heterocyclic group, and R １ is a group represented by CX １ Y １ R ４ and R ２ is a hydrogen atom or CX ２ Y ２ R ５ It is a group represented by R ３ is a hydrogen atom or CX ３ Y ３ R ６ It is a group represented by R ７ X is a perfluoroalkylene group having 1 to 5 carbon atoms (however, it may also contain an etheric oxygen atom), １ ~X ３ Each is independently a hydrogen atom, a fluorine atom, or R ｆ Y １ ~Y ３ Each of these is independently a fluorine atom or R ｆ And R ４ ~R ６ Each of these is an independent fluorine atom, R ｆ , OR ｆ Or an alkyl group having 1 to 6 carbon atoms, R ｆ These are independently fluoroalkyl groups having 1 to 4 carbon atoms or fluoroalkyl groups having 2 to 4 carbon atoms and an etheric oxygen atom. However, Ar is a divalent aromatic hydrocarbon group or a divalent aromatic heterocyclic group, and R ７ This is a perfluoroalkylene group having 1 to 5 carbon atoms (however, it may also contain an etheric oxygen atom), and has two R ７ They may be the same or different.

2. The method for producing polyester according to claim 1, wherein the compounds represented by formulas (1) to (3) are obtained by a reaction using at least one fluorine-containing alcohol (A1) selected from the group consisting of the compounds represented by formula (5) and the compounds represented by formula (6) below as a starting material. However, R １ CX １ Y １ R ４ It is a group represented by R ２ is a hydrogen atom or CX ２ Y ２ R ５ It is a group represented by R ３ is a hydrogen atom or CX ３ Y ３ R ６ It is a group represented by R ７ X is a perfluoroalkylene group having 1 to 5 carbon atoms (however, it may also contain an etheric oxygen atom), １ ~X ３ Each is independently a hydrogen atom, a fluorine atom, or R ｆ Y １ ~Y ３ Each of these is independently a fluorine atom or R ｆ And R ４ ~R ６ Each of these is an independent fluorine atom, R ｆ , OR ｆ Or an alkyl group having 1 to 6 carbon atoms, R ｆ These are independently fluoroalkyl groups having 1 to 4 carbon atoms or fluoroalkyl groups having 2 to 4 carbon atoms and an etheric oxygen atom.

3. R ​​in formula (5) above ２ However, CX ２ Y ２ R ５ A method for producing polyester according to claim 2, wherein the group is represented by 4. The method for producing polyester according to claim 1 or 2, wherein the carbon number of the fluorine-containing alcohol (A3) is 2 to 10.

5. The method for producing polyester according to claim 1 or 2, wherein the pKa of the fluorine-containing alcohol (A3) is less than 15.

6. The method for producing polyester according to claim 1 or 2, wherein the pKa of the fluorine-containing alcohol (A3) is less than 13.

7. The method for producing a polyester according to claim 1 or 2, wherein the fluorine-containing alcohol (A3) is at least one selected from the group consisting of 2,2,2-trifluoroethanol, 2,2,3,3-tetrafluoro-1-propanol, 2,2,3,3,3-pentafluoro-1-propanol, 1,1,1,3,3,3-hexafluoro-2-propanol, 2-fluoro-1-propanol, 2,2,3,4,4,4-hexafluoro-1-butanol, 2,2,3,3,4,4,5,5-octafluoro-1-pentanol, 2,2,3,3,4,4,5,5-octafluorocyclopentanol, perfluoro(t-butyl) alcohol, and 2,2,3,3,4,4,5,5,6,6-decafluorocyclohexanol.

8. The method for producing polyester according to claim 1 or 2, wherein the diol compound is an aromatic diol compound.

9. The method for producing a polyester according to claim 1 or 2, wherein the diol compound is bisphenol A.

10. The method for producing polyester according to claim 1 or 2, wherein the diol compound is an alicyclic diol compound.

11. The method for producing polyester according to claim 1 or 2, wherein the condensation catalyst is a nitrogen-containing compound.

12. The method for producing polyester according to claim 11, wherein the pKa of the nitrogen-containing compound is 9 to 15.

13. The method for producing polyester according to claim 11, wherein the vapor pressure of the nitrogen-containing compound is 1 to 10,000 Pa.

14. The method for producing a polyester according to claim 1 or 2, wherein the compound represented by formula (1) is at least one of bis(1,1,1,3,3,3-hexafluoropropyl) isophthalate represented by the following formula (1-1) and bis(1,1,1,3,3,3-hexafluoropropyl) terephthalate represented by the following formula (1-2).

15. A polymer represented by any one of the following formula (P1), formula (P2), and formula (P3). However, G1 is a monovalent group represented by the following formula (g1), a monovalent group represented by the following formula (g2), or a hydrogen atom; G2 is a hydrogen atom; Ar is a divalent aromatic hydrocarbon group or a divalent aromatic heterocyclic group; X ４ is a divalent group derived from an alicyclic diol compound; and m is an integer from 10 to 1000. However, R １ is a group represented by CX １ Y １ R ４ ; R ２ is a hydrogen atom or a group represented by CX ２ Y ２ R ５ ; R ３ is a hydrogen atom or a group represented by CX ３ Y ３ R ６ ; R ７ is a perfluoroalkylene group having 1 to 5 carbon atoms (however, it may contain an etheric oxygen atom); X １ to X ３ are each independently a hydrogen atom, a fluorine atom, or R ｆ ; Y １ to Y ３ are each independently a fluorine atom or R ｆ ; and R ４ to R ６ are each independently a fluorine atom, R ｆ , OR ｆ , or an alkyl group having 1 to 6 carbon atoms; and R ｆ is independently a fluoroalkyl group having 1 to 4 carbon atoms or a fluoroalkyl group having an etheric oxygen atom having 2 to 4 carbon atoms.

16. At least one of G1 in formula (P1) and formula (P3), and G2 in formula (P1) and formula (P2) is substituted with a substituent, where if G1 is substituted, the substituent is substituent (S1) or substituent (S2), where if G2 is substituted, the substituent is substituent (S3) or substituent (S4), and substituent (S1) is a monovalent group obtained by removing a hydroxyl group from at least one compound (s1) selected from the group consisting of phenol, cresol, p-t-butylphenol, 2,3,5-trimethylphenol, 2,3,6-trimethylphenol, and cumylphenol. The polymer according to claim 15, wherein the substituent (S2) is a monovalent group obtained by removing a hydroxyl group from at least one compound (s2) selected from the group consisting of methanol, ethanol, n-propanol, isopropanol, n-butanol, 2-butanol, pentanol, hexanol, dodecyl alcohol, stearyl alcohol, benzyl alcohol, and phenethyl alcohol; the substituent (S3) is a monovalent group obtained by removing a chlorine atom from at least one compound (s3) selected from the group consisting of benzoic acid chloride, methanesulfonyl chloride, and phenyl chloroformate; and the substituent (S4) is a monovalent group obtained by removing an OH from the carboxylic acid of at least one compound (s4) selected from the group consisting of acetic acid, propionic acid, octanoic acid, cyclohexanecarboxylic acid, benzoic acid, toluic acid, phenylacetic acid, p-t-butylbenzoic acid, and p-methoxyphenylacetic acid.

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