Method for producing fluorinated polyether group-containing carboxylic acid

Abstract

The present invention provides a method for producing a fluorinated polyether group-containing carboxylic acid using propionic acid from a fluorinated polyether group-containing carboxylic acid ester.

Description

Technical Field

[0001] The present invention relates to a method for producing a fluorinated polyether group-containing carboxylic acid. Background Art

[0002] Methods for producing fluoropolyether group-containing carboxylic acids from fluoropolyether group-containing carboxylic acid esters are known. For example, Patent Document 1 discloses a method for obtaining fluoropolyether group-containing carboxylic acids by hydrolyzing fluoropolyether group-containing carboxylic acid esters in the presence of an aqueous solution containing an alkali metal hydroxide.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: International Publication No. 2019 / 163712 Summary of the Invention

[0006] Technical problem to be solved by the invention

[0007] When the method described in Patent Document 1 is used, after obtaining the fluorinated polyether group-containing carboxylic acid, steps such as rapid cooling, liquid separation, dehydration, and concentration are required, making subsequent treatments complicated.

[0008] An object of the present invention is to provide a method for producing a fluorinated polyether group-containing carboxylic acid from a fluorinated polyether group-containing carboxylic acid ester, which allows for easy post-processing.

[0009] Technical means for solving technical problems

[0010] The present invention includes the following aspects.

[0011] [1] A method for producing a fluorinated polyether group-containing carboxylic acid, wherein the fluorinated polyether group-containing carboxylic acid is produced from a fluorinated polyether group-containing carboxylic acid ester using propionic acid.

[0012] [2] The production method according to [1] above, wherein the fluorinated polyether group-containing carboxylic acid ester is a compound represented by the following formula (1) or (2).

[0013] Rf 1 -R F -X-CO-O-R 1 (1)

[0014] R 1 -O-CO-X-Rf 2 -R F -X-CO-O-R 1 (2)

[0015] [Where,

[0016] Rf 1Each occurrence is independently C which may be substituted with one or more fluorine atoms. 1－16 alkyl,

[0017] Rf 2 C may be substituted by one or more fluorine atoms 1－6 Alkylene,

[0018] R F is independently a divalent fluoropolyether group at each occurrence,

[0019] X is a single bond or a divalent organic group,

[0020] R 1 C 1－6 alkyl.]

[0021] [3] The manufacturing method according to [2] above, wherein

[0022] R F Each occurrence is independently of the formula: -(OC6F 12 ) a -(OC5F 10 ) b -(OC4F8) c -(OC3R Fa 6) d -(OC2F4) e -(OCF2) f - the group shown.

[0023] [Where R Fa is independently a hydrogen atom, a fluorine atom or a chlorine atom at each occurrence,

[0024] a, b, c, d, e and f are each independently an integer of 0 to 200, the sum of a, b, c, d, e and f is 1 or more, and the order of the repeating units marked with a, b, c, d, e or f and enclosed in brackets in the formula is arbitrary, but in all R Fa When it is a hydrogen atom or a chlorine atom, at least one of a, b, c, e and f is 1 or more.]

[0025] [4] The manufacturing method according to [3] above, wherein R Fa is a fluorine atom.

[0026] [5] The production method according to any one of [2] to [4] above, wherein R F Each occurrence is independently a group represented by the following formula (f1), (f2), (f3), (f4), (f5) or (f6).

[0027] -(OC3F6)d -(OC2F4) e -(f1)

[0028] [Wherein, d is an integer from 1 to 200, and e is 0 or 1.]

[0029] -(OC4F8) c -(OC3F6) d -(OC2F4) e -(OCF2) f -(f2)

[0030] [wherein, c and d are each independently an integer of 0 to 30,

[0031] e and f are each independently an integer of 1 to 200,

[0032] The sum of c, d, e and f is an integer from 10 to 200,

[0033] The order of the repeating units marked with the subscript c, d, e or f and enclosed in parentheses in the formula is arbitrary.]

[0034] -(R 6 -R 7 ) g -(f3)

[0035] [Where R 6 is OCF2 or OC2F4,

[0036] R 7 is selected from OC2F4, OC3F6, OC4F8, OC5F 10 and OC6F 12 or a combination of two or three groups selected from these groups,

[0037] g is an integer from 2 to 100.]

[0038] -(R 6 -R 7 ) g -R r -(R 7' -R 6' ) g' - (f4)

[0039] [Where R 6 is OCF2 or OC2F4,

[0040] R 7 is selected from OC2F4, OC3F6, OC4F8, OC5F 10 and OC6F 12or a combination of two or three groups independently selected from these groups,

[0041] R 6' is OCF2 or OC2F4,

[0042] R 7' is selected from OC2F4, OC3F6, OC4F8, OC5F 10 and OC6F 12 or a combination of two or three groups independently selected from these groups,

[0043] g is an integer from 2 to 100,

[0044] g' is an integer from 2 to 100,

[0045] R r for:

[0046]

[0047] (Where * indicates the bonding position.)]

[0048] -(OC6F 12 ) a -(OC5F 10 ) b -(OC4F8) c -(OC3F6) d -(OC2F4) e -(OCF2) f -(f5)

[0049] [In the formula, e is an integer from 1 to 200, a, b, c, d, and f are each independently an integer from 0 to 200, and the order of presence of the repeating units indicated by a, b, c, d, e, or f and enclosed in parentheses in the formula is arbitrary.]

[0050] -(OC6F 12 ) a -(OC5F 10 ) b -(OC4F8) c -(OC3F6) d -(OC2F4) e -(OCF2) f -(f6)

[0051] [In the formula, f is an integer from 1 to 200, a, b, c, d, and e are each independently an integer from 0 to 200, and the order of presence of the repeating units indicated by a, b, c, d, e, or f and enclosed in parentheses in the formula is arbitrary.]

[0052] [6] The production method according to any one of [2] to [5] above, wherein R F Each occurrence is independently a group represented by the following formula (f2).

[0053] -(OC4F8) c -(OC3F6) d -(OC2F4) e -(OCF2) f -(f2)

[0054] [wherein, c and d are each independently an integer of 0 to 30,

[0055] e and f are each independently an integer of 1 to 200,

[0056] The sum of c, d, e and f is an integer from 10 to 200,

[0057] The order of the repeating units marked with the subscript c, d, e or f and enclosed in parentheses in the formula is arbitrary.]

[0058] [7] The production method according to any one of [2] to [6] above, wherein R 1 It is a methyl group.

[0059] [8] The production method according to any one of [2] to [7] above, wherein X is a single bond.

[0060] [9] The production method according to any one of [1] to [8] above, wherein the equivalent number of propionic acid relative to the ester group of the fluorinated polyether group-containing carboxylic acid ester is 2.0 equivalents or more.

[0061]

[10] The production method according to any one of [1] to [9] above, wherein the equivalent number of propionic acid relative to the ester group of the fluorinated polyether group-containing carboxylic acid ester is 2.8 equivalents or more.

[0062]

[11] The production method according to any one of [2] to [9] above, wherein R 1 is a methyl group, X is a single bond, R F Each occurrence is independently a group represented by the following formula (f2).

[0063] -(OC4F8) c -(OC3F6) d -(OC2F4) e -(OCF2) f -(f2)

[0064] [wherein, c and d are independently 0 or 1,

[0065] e and f are each independently an integer of 10 to 30,

[0066] The sum of c, d, e and f is an integer from 20 to 50,

[0067] The order of the repeating units marked with the subscript c, d, e or f and enclosed in parentheses in the formula is arbitrary.]

[0068]

[12] The production method according to any one of [1] to

[11] above, wherein water is also used.

[0069]

[13] The production method according to

[12] above, wherein the equivalent number of water relative to the ester group of the fluorinated polyether group-containing carboxylic acid ester is 10 equivalents or less.

[0070]

[14] The production method according to

[12] or

[13] above, wherein the equivalent number of water relative to the ester group of the fluorinated polyether group-containing carboxylic acid ester is 3.0 equivalents or less.

[0071]

[15] The production method according to any one of

[12] to

[14] above, wherein the equivalent number of water relative to the ester group of the fluorinated polyether group-containing carboxylic acid ester is 0.5 to 3.0 equivalents.

[0072]

[16] The production method as described in any one of

[12] to

[15] above, wherein the equivalent number of propionic acid relative to the ester group of the above-mentioned fluorinated polyether group-containing carboxylic acid ester is 2.0 equivalents or more, and the equivalent number of water relative to the ester group of the above-mentioned fluorinated polyether group-containing carboxylic acid ester is 10 equivalents or less.

[0073]

[17] The production method according to any one of [1] to

[16] , further comprising the step of mixing the fluorinated polyether group-containing carboxylic acid ester and propionic acid and heating the mixture to 100°C or higher.

[0074]

[18] The production method according to any one of [1] to

[16] , further comprising the step of mixing the fluorinated polyether group-containing carboxylic acid ester, propionic acid, and water and heating the mixture to 100°C or higher.

[0075] Effects of the Invention

[0076] According to the present invention, there can be provided a method for producing a fluorinated polyether group-containing carboxylic acid from a fluorinated polyether group-containing carboxylic acid ester, which allows for easy post-processing. DETAILED DESCRIPTION

[0077] The present invention provides a method for producing a fluorinated polyether group-containing carboxylic acid from a fluorinated polyether group-containing carboxylic acid ester using propionic acid.

[0078] (Fluoropolyether group-containing carboxylate)

[0079] The fluoropolyether group-containing carboxylate means a compound having a fluoropolyether group and a carboxylate group.

[0080] In a preferred embodiment, the fluorinated polyether group-containing carboxylic acid ester is a compound represented by the following formula (1) or (2).

[0081] Rf 1 -R F -X-CO-O-R 1 (1)

[0082] R 1 -O-CO-X-Rf 2 -R F -X-CO-O-R 1 (2)

[0083] [Where,

[0084] Rf 1 Each occurrence is independently C which may be substituted with one or more fluorine atoms. 1－16 alkyl,

[0085] Rf 2 C may be substituted by one or more fluorine atoms 1－6 Alkylene,

[0086] R F is independently a divalent fluoropolyether group at each occurrence,

[0087] X is a single bond or a divalent organic group,

[0088] R 1 C 1－6 alkyl.]

[0089] The fluorinated polyether group-containing carboxylic acids obtained from the fluorinated polyether group-containing carboxylates represented by formulae (1) and (2) are represented by the following formulae (3) and (4), respectively.

[0090] Rf 1 -R F -X-COOH(3)

[0091] HOCO-X-Rf 2 -R F -X-COOH(4)

[0092] In one embodiment, the fluorinated polyether group-containing carboxylic acid ester is a compound represented by formula (1).

[0093] In another embodiment, the fluorinated polyether group-containing carboxylic acid ester is a compound represented by formula (2).

[0094] In another embodiment, the fluorinated polyether group-containing carboxylic acid ester contains both the compound represented by formula (1) and the compound represented by formula (2).

[0095] In the above formula, Rf 1 Each occurrence is independently C which may be substituted with one or more fluorine atoms. 1－16 alkyl.

[0096] The above C may be substituted with one or more fluorine atoms 1－16 The "C" in the alkyl group 1－16 The "alkyl" may be a straight chain or a branched chain, preferably a straight chain or a branched chain C 1－6 Alkyl groups, especially C 1－3 Alkyl, more preferably a straight chain C 1－6 Alkyl groups, especially C 1－3 alkyl.

[0097] The above Rf 1 Preferably, C is substituted with one or more fluorine atoms. 1－16 Alkyl, more preferably CF2H-C 1－15 Perfluoroalkylene, more preferably C 1－16 Perfluoroalkyl.

[0098] The above C 1－16 The perfluoroalkyl group may be a linear or branched chain, preferably a linear or branched chain C 1－6 Perfluoroalkyl groups, especially C 1－3 Perfluoroalkyl, more preferably a straight chain C 1－6 Perfluoroalkyl groups, especially C 1－3 The perfluoroalkyl group may specifically be -CF3, -CF2CF3 or -CF2CF2CF3.

[0099] In the above formula, Rf 2 C may be substituted by one or more fluorine atoms 1－6 Alkylene.

[0100] The above C may be substituted with one or more fluorine atoms 1－6 The "C" in the alkylene 1－ 6 alkylene" can be straight chain or branched, preferably straight chain or branched C 1－3 Alkylene, more preferably linear C 1－3 Alkylene.

[0101] The above Rf 2 Preferably, C is substituted with one or more fluorine atoms. 1－6 Alkylene, more preferably C 1－6 Perfluoroalkylene, more preferably C 1－3 Perfluoroalkylene.

[0102] The above C 1－6 The perfluoroalkylene group may be a linear or branched group, preferably a linear or branched C 1－3 Perfluoroalkylene, more preferably linear C 1－3 The perfluoroalkyl group may specifically be -CF2-, -CF2CF2- or -CF2CF2CF2-.

[0103] In the above formula, R F Each occurrence is independently a divalent fluoropolyether group.

[0104] R F Preferably include the following: - (OC h1 R Fa 2h1 ) h3 -(OC h2 R Fa 2h2－2 ) h4 - the group shown.

[0105] [Where,

[0106] R Fa is independently a hydrogen atom, a fluorine atom or a chlorine atom at each occurrence,

[0107] h1 is an integer from 1 to 6,

[0108] h2 is an integer from 4 to 8,

[0109] h3 is an integer greater than 0,

[0110] h4 is an integer greater than 0,

[0111] The total of h3 and h4 is 1 or more, preferably 2 or more, and more preferably 5 or more, and the order of presence of the repeating units marked with h3 and h4 and enclosed in parentheses in the formula is arbitrary.]

[0112] In one embodiment, R F It can be straight chain or branched chain. F The preferred formula is: -(OC6F 12 ) a -(OC5F 10 ) b -(OC4F8) c -(OC3R Fa 6) d -(OC2F4) e -(OCF2) f - the group shown.

[0113] [Where,

[0114] R Fa is independently a hydrogen atom, a fluorine atom or a chlorine atom at each occurrence,

[0115] a, b, c, d, e and f are each independently an integer of 0 to 200, and the sum of a, b, c, d, e and f is 1 or more. The order of the repeating units indicated by a, b, c, d, e or f and enclosed in parentheses in the formula is arbitrary. However, in all R Fa When it is a hydrogen atom or a chlorine atom, at least one of a, b, c, e and f is 1 or more.]

[0116] R Fa Preferably, it is a hydrogen atom or a fluorine atom, more preferably a fluorine atom. Fa When it is a hydrogen atom or a chlorine atom, at least one of a, b, c, e and f is 1 or more.

[0117] a, b, c, d, e and f are each independently preferably an integer of 0 to 100, more preferably an integer of 0 to 60, for example, 1 to 100, 5 to 100, 10 to 100, 20 to 100, 25 to 100, 1 to 60, 5 to 60, 10 to 60, 20 to 60, 25 to 60, 1 to 50, 5 to 50, 10 to 50, 20 to 50, 25 to 50, 1 to 40, 5 to 40, 10 to 40, 20 to 40 or 25 to 40.

[0118] The sum of a, b, c, d, e, and f is preferably 5 or more, more preferably 10 or more, for example, 15 or more or 20 or more. The sum of a, b, c, d, e, and f is preferably 200 or less, more preferably 100 or less, further preferably 60 or less, for example, 50 or less or 30 or less. The sum of a, b, c, d, e, and f can be, for example, 15 to 100, 20 to 100, 15 to 60, 20 to 60, 15 to 50, or 20 to 50.

[0119] These repeating units can be linear or branched. For example, -(OC6F 12 )- can be -(OCF2CF2CF2CF2CF2CF2)-, -(OCF(CF3)CF2CF2CF2CF2)-, -(OCF2CF(CF3)CF2CF2CF2)-, -(OCF2CF2CF(CF3)CF2CF2)-, -(OCF2CF2CF2CF(CF3)CF2)-, -(OCF2CF2CF2CF2CF(CF3))-, etc. -(OC5F 10)- may be any of -(OCF2CF2CF2CF2CF2)-, -(OCF(CF3)CF2CF2CF2)-, -(OCF2CF(CF3)CF2CF2)-, -(OCF2CF2CF(CF3)CF2)-, -(OCF2CF2CF2CF(CF3))-, etc. -(OC4F8)- may be any of -(OCF2CF2CF2CF2)-, -(OCF(CF3)CF2CF2)-, -(OCF2CF(CF3)CF2)-, -(OCF2CF2CF(CF3)CF3))-, -(OC(CF3)2CF2)-, -(OCF2C(CF3)2)-, -(OCF(CF3)CF(CF3))-, -(OCF(C2F5)CF2)-, and -(OCF2CF(C2F5))-. -(OC3F6)-(i.e. R Fa is a fluorine atom) may be any of -(OCF2CF2CF2)-, -(OCF(CF3)CF2)-, and -(OCF2CF(CF3))-. -(OC2F4)- may be any of -(OCF2CF2)- and -(OCF(CF3))-.

[0120] In one embodiment, the repeating unit is linear.

[0121] In one embodiment, the repeating unit is branched.

[0122] In one embodiment, R F May contain ring structures.

[0123] The ring structure may be a three-membered ring, a four-membered ring, a five-membered ring, or a six-membered ring.

[0124]

[0125] [Where * represents the bonding position.]

[0126] The ring structure is preferably a four-membered ring, a five-membered ring or a six-membered ring, and more preferably a four-membered ring or a six-membered ring.

[0127] The repeating unit having a ring structure is preferably the following unit.

[0128]

[0129] [Where * represents the bonding position.]

[0130] In one embodiment, R F Each occurrence is independently a group represented by any one of the following formulae (f1) to (f6).

[0131] -(OC3F6) d-(OC2F4) e -(f1)

[0132] [Wherein, d is an integer from 1 to 200, and e is 0 or 1.]

[0133] -(OC4F8) c -(OC3F6) d -(OC2F4) e -(OCF2) f -(f2)

[0134] [wherein, c and d are each independently an integer from 0 to 30, e and f are each independently an integer from 1 to 200,

[0135] The sum of c, d, e and f is greater than 2,

[0136] The order of the repeating units marked with the subscript c, d, e or f and enclosed in parentheses in the formula is arbitrary.]

[0137] -(R 6 -R 7 ) g -(f3)

[0138] [Where R 6 is OCF2 or OC2F4,

[0139] R 7 is selected from OC2F4, OC3F6, OC4F8, OC5F 10 and OC6F 12 or a combination of two or three groups independently selected from these groups,

[0140] g is an integer from 2 to 100.]

[0141] -(R 6 -R 7 ) g -R r -(R 7' -R 6' ) g' - (f4)

[0142] [Where R 6 is OCF2 or OC2F4,

[0143] R 7 is selected from OC2F4, OC3F6, OC4F8, OC5F 10 and OC6F 12 or a combination of two or three groups independently selected from these groups,

[0144] R6' is OCF2 or OC2F4,

[0145] R 7' is selected from OC2F4, OC3F6, OC4F8, OC5F 10 and OC6F 12 or a combination of two or three groups independently selected from these groups,

[0146] g is an integer from 2 to 100,

[0147] g' is an integer from 2 to 100,

[0148] R r for:

[0149]

[0150] (Where * indicates the bonding position.)]

[0151] -(OC6F 12 ) a -(OC5F 10 ) b -(OC4F8) c -(OC3F6) d -(OC2F4) e -(OCF2) f -(f5)

[0152] [In the formula, e is an integer from 1 to 200, a, b, c, d, and f are each independently an integer from 0 to 200, and the order of presence of the repeating units indicated by a, b, c, d, e, or f and enclosed in parentheses in the formula is arbitrary.]

[0153] -(OC6F 12 ) a -(OC5F 10 ) b -(OC4F8) c -(OC3F6) d -(OC2F4) e -(OCF2) f -(f6)

[0154] [In the formula, f is an integer from 1 to 200, a, b, c, d, and e are each independently an integer from 0 to 200, and the order of presence of the repeating units indicated by a, b, c, d, e, or f and enclosed in parentheses in the formula is arbitrary.]

[0155] In the above formula (f1), d is preferably an integer of 5 to 200, more preferably an integer of 10 to 100, further preferably an integer of 15 to 50, for example, an integer of 25 to 35. In one embodiment, e is 1. In another embodiment, e is 0. In the above formula (f1), -(OC3F6) d -Preferably -(OCF2CF2CF2) d -or-(OCF(CF3)CF2) d -, more preferably -(OCF2CF2CF2) d - the group shown.

[0156] In the above formula (f2), e and f are each independently preferably an integer of 5 to 200, more preferably an integer of 10 to 200, further preferably an integer of 10 to 100, for example, an integer of 10 to 50, 10 to 30, or 20 to 30. c and d are each independently preferably 0 or 1. Furthermore, the sum of c, d, e, and f is preferably 5 or more, more preferably 10 or more, for example, 15 or more or 20 or more. For example, the sum of c, d, e, and f may be 15 or more and 100 or less, 15 or more and 60 or less, 15 or more and 50 or less, 20 or more and 60 or less, or 20 or more and 50 or less. In one embodiment, the above formula (f2) is preferably -(OCF2CF2CF2CF2) c -(OCF2CF2CF2) d -(OCF2CF2) e -(OCF2) f In another embodiment, formula (f2) may be -(OC2F4) e -(OCF2) f - the group shown.

[0157] In the above formula (f3), R 6 Preferably, it is OC2F4. In the above (f3), R 7It is preferably a group selected from OC2F4, OC3F6 and OC4F8, or a combination of two or three groups independently selected from these groups, and more preferably a group selected from OC3F6 and OC4F8. The combination of two or three groups independently selected from OC2F4, OC3F6 and OC4F8 is not particularly limited, and examples thereof include -OC2F4OC3F6-, -OC2F4OC4F8-, -OC3F6OC2F4-, -OC3F6OC3F6-, -OC3F6OC4F8-, -OC4F8OC4F8-, -OC4F8OC3F6-, -OC4F8OC2F4-, -OC2F 4OC2F4OC3F6-, -OC2F4OC2F4OC4F8-, -OC2F4OC3F6OC2F4-, -OC2F4OC3F6OC3F6-, -OC2F4OC4F8OC2F4-, -OC3F6OC2F4OC2F4-, -OC3F6OC2F4OC3F6-, -OC3F6OC3F6OC2F4- and -OC4F8OC2F4OC2F4-. In the above formula (f3), g is preferably an integer of 3 or more, more preferably an integer of 5 or more. The above g is preferably an integer of 50 or less. In the above formula (f3), OC2F4, OC3F6, OC4F8, OC5F 10 and OC6F 12 It can be either a straight chain or a branched chain, preferably a straight chain. In this embodiment, the above formula (f3) is preferably -(OC2F4-OC3F6) g - or - (OC2F4-OC4F8) g -.

[0158] In the above formula (f4), R 6 、R 7 and g have the same meanings as those in the above formula (f3) and have the same form. 6' 、R 7' and g' respectively have the same meanings as R in the above formula (f3). 6 、R 7 Same as g, in the same way. r Preferably:

[0159]

[0160] [Where * represents the bonding position.]

[0161] More preferably:

[0162]

[0163] [Where * represents the bonding position.]

[0164] In the above formula (f5), e is preferably an integer from 1 to 100, more preferably an integer from 5 to 100. The sum of a, b, c, d, e and f is preferably 5 or more, more preferably 10 or more, for example, 10 or more and 100 or less.

[0165] In the above formula (f6), f is preferably an integer of 1 to 100, more preferably an integer of 5 to 100. The sum of a, b, c, d, e and f is preferably 5 or more, more preferably 10 or more, for example, 10 or more and 100 or less.

[0166] In one embodiment, the above R F It is a group represented by the above formula (f1).

[0167] In one embodiment, the above R F It is a group represented by the above formula (f2).

[0168] In one embodiment, the above R F It is a group represented by the above formula (f3).

[0169] In one embodiment, the above R F It is a group represented by the above formula (f4).

[0170] In one embodiment, the above R F It is a group represented by the above formula (f5).

[0171] In one embodiment, the above R F It is a group represented by the above formula (f6).

[0172] In the above R F The ratio of e to f (hereinafter referred to as "e / f ratio") is 0.1 to 10, preferably 0.2 to 5, more preferably 0.2 to 2, further preferably 0.2 to 1.5, and still further preferably 0.2 to 0.85.

[0173] In the above-mentioned fluorinated polyether group-containing silane compound, R F The number average molecular weight of the moiety is not particularly limited, but is, for example, 500 to 30,000, preferably 1,500 to 30,000, and more preferably 2,000 to 10,000. F1 and R F2 The number average molecular weight is 19 The value measured by F-NMR.

[0174] In another approach, R F1 and R F2The number average molecular weight of the moiety may be 500 to 30,000, preferably 1,000 to 20,000, more preferably 2,000 to 15,000, further preferably 2,000 to 10,000, for example, 3,000 to 6,000.

[0175] In another approach, R F1 and R F2 The number average molecular weight of the moiety may be 4,000 to 30,000, preferably 5,000 to 10,000, and more preferably 6,000 to 10,000.

[0176] In the above formula, X is a single bond or a divalent organic group.

[0177] In one embodiment, X is a single bond.

[0178] In another embodiment, X is a divalent organic group.

[0179] As used herein, a "divalent organic group" refers to a divalent group containing carbon. The divalent organic group is not particularly limited and may be a divalent hydrocarbon group or a derivative thereof. A derivative of a hydrocarbon group refers to a group having one or more N, O, S, Si, amide, sulfonyl, siloxane, carbonyl, carbonyloxy, or the like at the end of the hydrocarbon group or in the molecular chain.

[0180] As used in this specification, a "divalent hydrocarbon group" is a group containing carbon and hydrogen, and refers to a group obtained by removing two hydrogen atoms from a hydrocarbon. Such a hydrocarbon group is not particularly limited, and examples thereof include divalent C 1－20 Hydrocarbon groups, such as aliphatic hydrocarbon groups and aromatic hydrocarbon groups. The aforementioned "aliphatic hydrocarbon groups" may be linear, branched, or cyclic, and may be saturated or unsaturated. Furthermore, the hydrocarbon group may contain one or more ring structures. The aforementioned "divalent hydrocarbon group" may be substituted with one or more substituents.

[0181] As used in this specification, the substituent of the "hydrocarbon group" is not particularly limited, and examples thereof include halogen atoms, C 1－ 6 alkyl, C 2－6 Alkenyl, C 2－6 Alkynyl, C 3－10 Cycloalkyl, C 3－10 Unsaturated cycloalkyl, 5-10 membered heterocyclic group, 5-10 membered unsaturated heterocyclic group, C 6－10 One or more of aryl and 5- to 10-membered heteroaryl groups.

[0182] The above-mentioned divalent organic group is preferably C 1－6 Alkylene, -(CH2)z1 -O-(CH2) z2 -(wherein, z1 is an integer of 0 to 6, for example, an integer of 1 to 6, and z2 is an integer of 0 to 6, for example, an integer of 1 to 6) or -(CH2) z3 -phenylene-(CH2) z4 - (wherein z3 is an integer of 0 to 6, for example, an integer of 1 to 6, and z4 is an integer of 0 to 6, for example, an integer of 1 to 6). 1－6 The alkylene group may be a straight chain or a branched chain, preferably a straight chain. 1－6 Alkyl, C 2－6 Alkenyl and C 2－6 The alkynyl group may be substituted with one or more substituents, but is preferably unsubstituted.

[0183] In the above formula, R 1 C 1－6 alkyl.

[0184] The above C 1－6 The alkyl group may be a straight chain or a branched chain. 1－6 In another embodiment, the alkyl group is a straight chain. 1－6 The alkyl group is a branched chain. 1－6 The alkyl group is preferably C 1－ 4 alkyl, more preferably C 1－3 The alkyl group is more preferably a methyl group or an ethyl group, and even more preferably a methyl group.

[0185] (Formation of Fluorinated Polyether Group-Containing Carboxylic Acid)

[0186] The use of propionic acid in the method of the present invention allows for the conversion of a fluoropolyether group-containing carboxylic acid ester into a fluoropolyether group-containing carboxylic acid at a higher conversion rate and in a shorter time compared to the use of other acids, such as formic acid. Furthermore, the use of propionic acid reduces the impact on the equipment compared to the use of inorganic acids such as hydrochloric acid, for example, preventing corrosion of the reactor.

[0187] In the production method of the present invention, the fluoropolyether group-containing carboxylic acid ester is hydrolyzed, without being bound by any theory.

[0188] (Implementation Method 1)

[0189] In the first embodiment, the production method of the present invention is carried out as follows using a fluorinated polyether group-containing carboxylic acid ester and propionic acid.

[0190] A predetermined amount of a fluorinated polyether group-containing carboxylic acid ester and a predetermined equivalent amount of propionic acid relative to the fluorinated polyether group-containing carboxylic acid ester are added to a reaction vessel and mixed. The mixture is stirred at high temperature. After a predetermined time, volatile components are removed by distillation under reduced pressure to obtain a fluorinated polyether group-containing carboxylic acid.

[0191] In this embodiment, propionic acid is added all at once, which makes the operation easier.

[0192] In the production method of the present invention, the amount of propionic acid used is preferably 2.0 equivalents or more, more preferably 2.8 equivalents or more, for example, 5.0 equivalents or more or 5.2 equivalents or more, relative to the ester groups of the fluoropolyether group-containing carboxylate. Furthermore, the amount of propionic acid used is preferably 20 equivalents or less, more preferably 10 equivalents or less, for example, 6.0 equivalents or less, relative to the ester groups of the fluoropolyether group-containing carboxylate. By adjusting the amount of propionic acid used within this range, the reaction rate from the fluoropolyether group-containing carboxylate to the fluoropolyether group-containing carboxylic acid is accelerated.

[0193] Here, the number of ester groups of the fluorinated polyether group-containing carboxylic acid ester can be determined based on the weight of the fluorinated polyether group-containing carboxylic acid ester and 19 The measurement results of F-NMR were calculated.

[0194] The reaction temperature is preferably 100° C. or higher, more preferably 110° C. or higher, and even more preferably 130° C. or higher. The upper limit of the reaction temperature is not particularly limited as long as the compound does not decompose, and may be, for example, 180° C. or lower, preferably 150° C. or lower.

[0195] The reaction time of the above reaction is preferably 20 hours or longer, more preferably 30 hours or longer, for example 40 hours or longer. The upper limit of the reaction time is not particularly limited, and for example, it may be 100 hours or shorter.

[0196] (Implementation Method 2)

[0197] In the second embodiment, the production method of the present invention is carried out as follows using a fluorinated polyether group-containing carboxylic acid ester, propionic acid, and water.

[0198] A predetermined amount of a fluoropolyether group-containing carboxylic acid ester, a predetermined equivalent amount of propionic acid and water relative to the fluoropolyether group-containing carboxylic acid ester are added to a reaction vessel and mixed. The mixture is stirred at high temperature. After a predetermined time, volatile components are removed by distillation under reduced pressure to obtain a fluoropolyether group-containing carboxylic acid.

[0199] In Embodiment 2, water is further used in addition to Embodiment 1. The use of water accelerates the reaction rate from the fluorinated polyether group-containing carboxylate to the fluorinated polyether group-containing carboxylic acid. In this embodiment, propionic acid and water are added at once. This simultaneous addition facilitates handling.

[0200] In this embodiment, the amount of water used is preferably 10 equivalents or less, more preferably 3 equivalents or less, relative to the ester group of the fluoropolyether group-containing carboxylate. The amount of water used is preferably 0.1 equivalents or more, more preferably 0.5 equivalents or more, for example, 1.0 equivalents or more or 2.0 equivalents or more, relative to the ester group of the fluoropolyether group-containing carboxylate. By setting the amount of water used within the above range, the reaction rate from the fluoropolyether group-containing carboxylate to the fluoropolyether group-containing carboxylic acid is accelerated.

[0201] In this embodiment, the amount of propionic acid used, the reaction temperature, and the reaction time may be the same as those in the first embodiment.

[0202] (Implementation 3)

[0203] In the third embodiment, the production method of the present invention is carried out as follows using a fluorinated polyether group-containing carboxylic acid ester, propionic acid, and water.

[0204] A predetermined amount of a fluoropolyether group-containing carboxylic acid ester, a predetermined equivalent amount of propionic acid and water relative to the amount of the fluoropolyether group-containing carboxylic acid ester, and mixture are added to a reaction vessel and mixed. The mixture is stirred at elevated temperature. After a predetermined time, preferably when the reaction approaches equilibrium, a predetermined equivalent amount of propionic acid and water relative to the amount of unreacted ester groups are added, and stirring is continued at elevated temperature. Volatile components are removed by distillation under reduced pressure to obtain a fluoropolyether group-containing carboxylic acid.

[0205] In Embodiment 2, water is further used in addition to Embodiment 1. The use of water accelerates the reaction rate from the fluorinated polyether group-containing carboxylate to the fluorinated polyether group-containing carboxylic acid. In this embodiment, propionic acid and water are added at once. This simultaneous addition facilitates handling.

[0206] By adding propionic acid and water in two separate additions, a high conversion rate can be achieved in a shorter time. While the addition is split into two separate additions in this embodiment, split additions may also be performed in multiple additions. The number of additions is not particularly limited and may be, for example, 2 to 5, preferably 2 or 3. Furthermore, even when no water is used, the propionic acid may be added in multiple additions.

[0207] When propionic acid and water are added in multiple additions, the amounts added are preferably equivalent to those in the first addition relative to the unreacted ester groups of the fluoropolyether group-containing carboxylic acid ester at the time of addition. For example, when propionic acid and water are initially used in amounts of 5.0 equivalents and 2.5 equivalents, respectively, relative to the ester groups of the fluoropolyether group-containing carboxylic acid ester, it is preferred that 5.0 equivalents and 2.5 equivalents, respectively, be used in the second and subsequent additions.

[0208] In this embodiment, the usage amounts of propionic acid and water, the reaction temperature, and the reaction time are the same as those in Embodiments 1 and 2. However, the usage amount means the total of all additions.

[0209] Example

[0210] The articles of the present invention are described below using examples, but the present invention is not limited to the following examples. In these examples, the order of the repeating units constituting the fluoropolyether is arbitrary, and the chemical formula shown below represents the average composition.

[0211] Example 1

[0212] To a 100 mL four-necked flask equipped with a reflux cooler, a thermometer and a stirrer were added 2,000 mol / L of an average composition of CH3OCOCF2O (CF2CF2O) 23 (CF2O) 22 To a perfluoropolyether-modified methyl ester (1) (51.6 g) represented by CF2COOCH3 (wherein the mixture further contains a compound containing a trace amount of (CF2CF2CF2O) and / or (CF2CF2CF2CF2O) repeating units), water (1.2 g, 2.6 equivalents relative to the ester group of the compound (1)) and propionic acid (9.3 g, 5.3 equivalents relative to the ester group of the compound (1)) were added in two portions. When the second reagent was added, the cooling water of the reflux cooler was stopped, and the mixture was stirred at 110°C to 130°C for 32 hours. 19 After confirming a conversion rate of 99% or higher by F-NMR, volatile components were distilled off under reduced pressure to obtain 51.1 g of a perfluoropolyether compound (2) having a terminal carboxyl group. The obtained product contained trace amounts of water and propionic acid.

[0213] HOOCCF2O(CF2CF2O) 23 (CF2O) 22 CF2COOH(2)

[0214] Example 2

[0215] To a 100 mL four-necked flask equipped with a reflux cooler, a thermometer and a stirrer were added 2,000 mol / L of an average composition of CH3OCOCF2O (CF2CF2O) 23 (CF2O) 22To a perfluoropolyether-modified methyl ester (1) (50.3 g) represented by CF2COOCH3 (wherein the mixture further contains a compound containing a trace amount of (CF2CF2CF2O) and / or (CF2CF2CF2CF2O) repeating units), water (1.4 g, 2.8 equivalents relative to the ester group of the compound (1)) and propionic acid (5.0 g, 2.8 equivalents relative to the ester group of the compound (1)) were added in 4 portions. When the second reagent was added, the cooling water of the reflux cooler was stopped, and the mixture was stirred at 120°C for 40 hours. 19 After confirming a conversion rate of 99% or higher by F-NMR, volatile components were distilled off under reduced pressure to obtain 49.5 g of a perfluoropolyether compound (2) having a terminal carboxyl group. The obtained product contained trace amounts of water and propionic acid.

[0216] Example 3

[0217] To a 100 mL four-necked flask equipped with a reflux cooler, a thermometer and a stirrer were added 2,000 mol / L of an average composition of CH3OCOCF2O (CF2CF2O) 23 (CF2O) 22 To a perfluoropolyether-modified methyl ester (1) (50.2 g) represented by CF2COOCH3 (wherein the mixture also contains a small amount of a compound containing a small amount of (CF2CF2CF2O) and / or (CF2CF2CF2CF2O) repeating units), propionic acid (9.1 g, 5.2 equivalents relative to the ester group of the compound (1)) was added in 4 portions and stirred at 120°C for 88 hours. 19 After confirming a conversion rate of 99% or higher by F-NMR, volatile components were distilled off under reduced pressure to obtain 49.4 g of a perfluoropolyether compound (2) having a terminal carboxyl group. The obtained product contained trace amounts of water and propionic acid.

[0218] Example 4

[0219] To a 100 mL four-necked flask equipped with a reflux cooler, a thermometer and a stirrer were added 2,000 mol / L of an average composition of CH3OCOCF2O (CF2CF2O) 23 (CF2O) 22 To a perfluoropolyether-modified methyl ester (1) (51.0 g) represented by CF2COOCH3 (wherein the mixture further contains a compound containing a trace amount of (CF2CF2CF2O) and / or (CF2CF2CF2CF2O) repeating units), water (4.0 g, 9.5 equivalents relative to the ester group of the compound (1)) was added in 4 portions, and propionic acid (8.9 g, 5.2 equivalents relative to the ester group of the compound (1)) was added in 6 portions. When the propionic acid was added for the 5th time, the cooling water of the reflux cooler was stopped, and the mixture was stirred at 100°C to 120°C for 82 hours.19 After confirming a conversion rate of 99% or higher by F-NMR, volatile components were distilled off under reduced pressure to obtain 50.2 g of a perfluoropolyether compound (2) having a terminal carboxyl group. The obtained product contained trace amounts of water and propionic acid.

[0220] Comparative Example 1

[0221] To a 100 mL four-necked flask equipped with a reflux cooler, a thermometer and a stirrer were added 2,000 mol / L of an average composition of CH3OCOCF2O (CF2CF2O) 23 (CF2O) 22 To a perfluoropolyether modified methyl ester (1) (51.6 g) represented by CF2COOCH3 (wherein the mixture also contains a compound containing a trace amount of (CF2CF2CF2O) and / or (CF2CF2CF2CF2O) repeating units), water (1.2 g, 2.6 equivalents relative to the ester group of the compound (1)) was added in two portions. During the second addition, the cooling water of the reflux cooler was stopped, and the mixture was stirred at 110°C to 130°C for 280 hours. 19 After confirming a conversion rate of 99% or higher by F-NMR, volatile components were distilled off under reduced pressure to obtain 51.0 g of a perfluoropolyether compound (2) having a terminal carboxyl group. The obtained product contained trace amounts of water and propionic acid.

[0222] Comparative Example 2

[0223] To a 100 mL four-necked flask equipped with a reflux cooler, a thermometer and a stirrer were added 2,000 mol / L of an average composition of CH3OCOCF2O (CF2CF2O) 23 (CF2O) 22 To a perfluoropolyether-modified methyl ester (1) (51.6 g) represented by CF2COOCH3 (wherein the mixture also contains a compound containing a trace amount of (CF2CF2CF2O) and / or (CF2CF2CF2CF2O) repeating units), water (1.2 g, 2.6 equivalents relative to the ester group of the compound (1)) and formic acid (5.8 g, 5.3 equivalents relative to the ester group of the compound (1)) were added in two portions. When the reagent was added for the second time, the cooling water of the reflux cooler was stopped, and the mixture was stirred at 110°C to 130°C for 100 hours. 19 The conversion rate was confirmed by F-NMR and found to be 80%.

[0224] Comparative Example 3

[0225] To a 100 mL four-necked flask equipped with a reflux cooler, a thermometer and a stirrer were added 2,000 mol / L of an average composition of CH3OCOCF2O (CF2CF2O) 23 (CF2O) 22To a perfluoropolyether-modified methyl ester (1) (50.3 g) represented by CF2COOCH3 (wherein the mixture also contains a compound containing a trace amount of (CF2CF2CF2O) and / or (CF2CF2CF2CF2O) repeating units), water (1.4 g, 2.8 equivalents relative to the ester group of the compound (1)) and formic acid (3.1 g, 2.8 equivalents relative to the ester group of the compound (1)) were added in 4 portions. When the reagent was added for the second time, the cooling water of the reflux cooler was stopped, and the mixture was stirred at 120°C for 100 hours. 19 The conversion rate was confirmed by F-NMR and found to be 71%.

[0226] [Table 1]

[0227]

[0228] Industrial applicability

[0229] The production method of the present invention is suitable for producing a fluorinated polyether group-containing carboxylic acid.

Claims

1. A method for producing a fluorinated polyether group-containing carboxylic acid, characterized in that: A fluorinated polyether group-containing carboxylic acid is produced from a fluorinated polyether group-containing carboxylic acid ester using propionic acid.

2. The manufacturing method according to claim 1, wherein The fluorinated polyether group-containing carboxylic acid ester is a compound represented by the following formula (1) or (2): Rf 1 -R F -X-CO-O-R 1 (1) R 1 -O-CO-X-Rf 2 -R F -X-CO-O-R 1 (2) Where, Rf 1 Each occurrence is independently C which may be substituted with one or more fluorine atoms. 1－16 alkyl, Rf 2 C may be substituted by one or more fluorine atoms 1－6 Alkylene, R F is independently a divalent fluoropolyether group at each occurrence, X is a single bond or a divalent organic group, R 1 C 1－6 alkyl.

3. The manufacturing method according to claim 2, wherein: R F Each occurrence is independently of the formula: -(OC6F 12 ) a -(OC5F 10 ) b -(OC4F8) c -(OC3R Fa 6) d -(OC2F4) e -(OCF2) f - the group shown, Where R Fa is independently a hydrogen atom, a fluorine atom or a chlorine atom at each occurrence, a, b, c, d, e and f are each independently an integer of 0 to 200, the sum of a, b, c, d, e and f is 1 or more, and the order of the repeating units marked with a, b, c, d, e or f and enclosed in brackets in the formula is arbitrary, but in all R Fa When it is a hydrogen atom or a chlorine atom, at least one of a, b, c, e and f is 1 or more.

4. The manufacturing method according to claim 3, wherein: R Fa is a fluorine atom.

5. The manufacturing method according to claim 2, wherein: R F Each occurrence is independently a group represented by the following formula (f1), (f2), (f3), (f4), (f5) or (f6), -(OC3F6) d -(OC2F4) e -(f1) In formula (f1), d is an integer from 1 to 200, and e is 0 or 1; <h2 style=";text-align:left;direction:ltr">(OC4F8)<h2 style=";text-align:left;direction:ltr"> c <h2 style=";text-align:left;direction:ltr"> (OC3F6)<h2 style=";text-align:left;direction:ltr"> d <h2 style=";text-align:left;direction:ltr"> (OC2F4)<h2 style=";text-align:left;direction:ltr"> e <h2 style=";text-align:left;direction:ltr"> (OCF2)<h2 style=";text-align:left;direction:ltr"> f <h2 style=";text-align:left;direction:ltr"> (f2) In formula (f2), c and d are each independently an integer of 0 to 30, e and f are each independently an integer of 1 to 200, The sum of c, d, e and f is an integer from 10 to 200, The order of presence of the repeating units marked with the subscript c, d, e or f and enclosed in brackets in the formula is arbitrary; -(R 6 -R 7 ) g -(f3) In formula (f3), R 6 is OCF2 or OC2F4, R 7 is selected from OC2F4, OC3F6, OC4F8, OC5F 10 and OC6F 12 or a combination of two or three groups selected from these groups, g is an integer from 2 to 100; -(R 6 -R 7 ) g -R r -(R 7' -R 6' ) g' -(f4) In formula (f4), R 6 is OCF2 or OC2F4, R 7 is selected from OC2F4, OC3F6, OC4F8, OC5F 10 and OC6F 12 or a combination of two or three groups independently selected from these groups, R 6' is OCF2 or OC2F4, R 7' is selected from OC2F4, OC3F6, OC4F8, OC5F 10 and OC6F 12 or a combination of two or three groups independently selected from these groups, g is an integer from 2 to 100, g' is an integer from 2 to 100, R r for: Where, * represents the bonding position; -(OC6F 12 ) a -(OC5F 10 ) b -(OC4F8) c -(OC3F6) d -(OC2F4) e -(OCF2) f -(f5) In formula (f5), e is an integer from 1 to 200, a, b, c, d, and f are each independently an integer from 0 to 200, and the order of presence of the repeating units marked with a, b, c, d, e, or f and enclosed in parentheses in the formula is arbitrary; -(OC6F 12 ) a -(OC5F 10 ) b -(OC4F8) c -(OC3F6) d -(OC2F4) e -(OCF2) f -(f6) In formula (f6), f is an integer from 1 to 200, a, b, c, d and e are each independently an integer from 0 to 200, and the order of presence of each repeating unit marked with a, b, c, d, e or f and enclosed in parentheses in the formula is arbitrary.

6. The manufacturing method according to claim 2, wherein: R F Each occurrence is independently a group represented by the following formula (f2), <h2 style=";text-align:left;direction:ltr">(OC4F8)<h2 style=";text-align:left;direction:ltr"> c <h2 style=";text-align:left;direction:ltr"> (OC3F6)<h2 style=";text-align:left;direction:ltr"> d <h2 style=";text-align:left;direction:ltr"> (OC2F4)<h2 style=";text-align:left;direction:ltr"> e <h2 style=";text-align:left;direction:ltr"> (OCF2)<h2 style=";text-align:left;direction:ltr"> f <h2 style=";text-align:left;direction:ltr"> (f2) In the formula, c and d are each independently an integer of 0 to 30, e and f are each independently an integer of 1 to 200, The sum of c, d, e and f is an integer from 10 to 200, The order of presence of the repeating units marked with a superscript c, d, e or f and enclosed in parentheses in the formula is arbitrary.

7. The manufacturing method according to claim 2, wherein: R 1 It is a methyl group.

8. The manufacturing method according to claim 2, wherein: X is a single bond.

9. The manufacturing method according to claim 1, wherein: The equivalent number of propionic acid relative to the ester group of the fluorinated polyether group-containing carboxylic acid ester is 2.0 equivalents or more.

10. The manufacturing method according to claim 1, wherein The equivalent number of propionic acid relative to the ester group of the fluorinated polyether group-containing carboxylic acid ester is 2.8 equivalents or more.

11. The manufacturing method according to claim 2, wherein: R 1 is methyl, X is a single bond, R F Each occurrence is independently a group represented by the following formula (f2), <h2 style=";text-align:left;direction:ltr">(OC4F8)<h2 style=";text-align:left;direction:ltr"> c <h2 style=";text-align:left;direction:ltr"> (OC3F6)<h2 style=";text-align:left;direction:ltr"> d <h2 style=";text-align:left;direction:ltr"> (OC2F4)<h2 style=";text-align:left;direction:ltr"> e <h2 style=";text-align:left;direction:ltr"> (OCF2)<h2 style=";text-align:left;direction:ltr"> f <h2 style=";text-align:left;direction:ltr"> (f2) In the formula, c and d are independently 0 or 1, e and f are each independently an integer of 10 to 30, The sum of c, d, e and f is an integer from 20 to 50, The order of presence of the repeating units marked with a superscript c, d, e or f and enclosed in parentheses in the formula is arbitrary.

12. The manufacturing method according to claim 1, wherein Water is also used.

13. The manufacturing method according to claim 12, wherein: The equivalent amount of water relative to the ester group of the fluorinated polyether group-containing carboxylic acid ester is 10 equivalents or less.

14. The manufacturing method according to claim 12, wherein: The equivalent weight of water relative to the ester group of the fluorinated polyether group-containing carboxylic acid ester is 3.0 equivalents or less.

15. The manufacturing method according to claim 12, wherein: The equivalent amount of water is 0.5 to 3.0 equivalents relative to the ester group of the fluorinated polyether group-containing carboxylic acid ester.

16. The manufacturing method according to claim 12, wherein: The equivalent number of propionic acid relative to the ester group of the fluorinated polyether group-containing carboxylic acid ester is 2.0 equivalents or more, and the equivalent number of water relative to the ester group of the fluorinated polyether group-containing carboxylic acid ester is 10 equivalents or less.

17. The manufacturing method according to claim 1, wherein: The method comprises the steps of mixing the carboxylate containing the fluorinated polyether group and propionic acid and heating the mixture to above 100° C.

18. The manufacturing method according to claim 1, wherein: The method comprises the steps of mixing the fluorinated polyether group-containing carboxylic acid ester, propionic acid and water and heating the mixture to above 100° C.

Images