Compound, composition, and method for producing compound

Abstract

This compound has a perfluoropolyether chain, a number average molecular weight of 40,000 or more, and is obtained by polymerizing, by irradiating with ultraviolet rays, a compound having one or more perfluoroalkyleneoxy units and having, at a terminal, at least one group selected from the group consisting of a carboxyl group and an alkoxycarbonyl group, wherein 1 part by mass or more of the compound is dissolved in 100 parts by mass of 1,1,1,2,2,3,3,4,4,5,5,6,6-tridecafluorohexane at 25°C.

Description

Compounds, compositions, and methods for making compounds

[0001] The present disclosure relates to compounds, compositions, and methods for making compounds.

[0002] Compounds having perfluoropolyether chains (hereinafter also referred to as "PFPE chains") have excellent heat resistance, electrical insulation, and oxidation resistance, and have low glass transition temperatures, making them suitable for a variety of industrial applications. In particular, compounds having perfluoropolyether chains exhibit water and oil repellency, making them suitable for use as coating agents. Patent Document 1 discloses a compound obtained by using a compound having perfluoroalkyleneoxy units and carbonyl fluoride groups at both ends as a raw material compound, and polymerizing this raw material compound by irradiating it with ultraviolet light. The compound obtained by this method has a molecular weight of 500 to 15,000.

[0003] U.S. Pat. No. 3,849,504

[0004] In recent years, there has been a demand for coating agents containing compounds having PFPE chains (hereinafter also referred to as "PFPE compounds") that can form high-strength surface layers. One method for forming a high-strength surface layer is to increase the molecular weight of the PFPE compound. However, according to the present inventors, the method described in Patent Document 1 makes it difficult to increase the molecular weight due to the formation of branched structures in the PFPE chains, making it difficult to obtain a high-molecular-weight PFPE compound. Furthermore, further polymerization of a PFPE compound having a branched structure and a carbonyl fluoride group at the end of the side chain results in the formation of a crosslinked structure, resulting in a compound that is difficult to flow and dissolve in solvents, making it difficult to apply to wet coating agents.

[0005] The present disclosure has been made in view of the above circumstances, and an object of one embodiment of the present disclosure is to provide a novel compound that has a perfluoropolyether chain, is applicable to a wet coating agent, and forms a high-strength surface layer when applied to the wet coating agent, and a composition containing the compound.An object of one embodiment of the present disclosure is to provide a method for producing a novel compound that has a perfluoropolyether chain, is applicable to a wet coating agent, and forms a high-strength surface layer when applied to the wet coating agent.

[0006] The present disclosure includes the following aspects. <1> A compound having a perfluoropolyether chain and a number average molecular weight of 40,000 or more, which dissolves at 25°C in an amount of 1 part by mass or more in 100 parts by mass of 1,1,1,2,2,3,3,4,4,5,5,6,6-tridecafluorohexane. <2> The compound according to <1>, which is a compound represented by the following formula (1): T １１ -O-Rf １ -T １２ ...Formula (1) In formula (1), T １１ and T １２ are each independently -R １１ -F, -R １１ -COOH or -R １１ -COOR １２ and R １１ are each independently a perfluoroalkylene group, and R １２ are each independently an alkyl group, and Rf １ is (R １３ O) ｎ１ and R １３are each independently a perfluoroalkylene group, and n1 is an integer of 130 or more. <3> A composition comprising the compound according to <1> or <2> and a fluorine-containing solvent. <4> A method for producing a compound having a perfluoropolyether chain, comprising irradiating a raw material compound having one or more perfluoroalkyleneoxy units and having at least one type selected from the group consisting of a carboxy group and an alkyloxycarbonyl group at a terminal, wherein the average total number of carboxy groups and alkyloxycarbonyl groups present in one molecule is 1.90 to 2.00 with ultraviolet light having a wavelength of 150 to 300 nm under a flow of inert gas, thereby polymerizing the raw material compound. <5> A method for producing the compound according to <4>, wherein the raw material compound includes a molecule having a structure represented by the following formula (2): T ２１ -O-Rf ２ -T ２２ ...Formula (2) In formula (2), T ２１ and T ２２ are each independently -R ２１ -COOH or -R ２１ -COOR ２２ and R ２１ are each independently a perfluoroalkylene group, and R ２２ are each independently an alkyl group, and Rf ２ is (R ２３ O) ｎ２ and R ２３ are each independently a perfluoroalkylene group, and n2 is an integer of 1 to 75. <6> The method for producing a compound according to <4> or <5>, wherein the irradiation of the raw material compound with ultraviolet light is carried out by irradiating a mixture of the raw material compound and a fluorine-containing solvent with ultraviolet light. <7> The method for producing a compound according to any one of <4> to <6>, wherein the temperature of the raw material compound during the irradiation with ultraviolet light is 0 to 150°C.

[0007] According to one embodiment of the present disclosure, there are provided a novel compound having a perfluoropolyether chain, which is applicable to a wet coating agent and which forms a high-strength surface layer when applied to the wet coating agent, and a composition containing the compound. According to one embodiment of the present disclosure, there is provided a method for producing a novel compound having a perfluoropolyether chain, which is applicable to a wet coating agent and which forms a high-strength surface layer when applied to the wet coating agent.

[0008] In the present disclosure, numerical ranges indicated using "to" include the numerical values ​​before and after "to" as the minimum and maximum values, respectively. In numerical ranges described in stages in the present disclosure, the upper or lower limit value described in one numerical range may be replaced with the upper or lower limit value of another numerical range described in stages. Furthermore, in numerical ranges described in the present disclosure, the upper or lower limit value of that numerical range may be replaced with a value shown in an example.

[0009] The terms used in this disclosure have the following meanings: A perfluoroalkyl group refers to a group in which all hydrogen atoms of an alkyl group are substituted with fluorine atoms; a perfluoroalkylene group refers to a group in which all hydrogen atoms of an alkylene group are substituted with fluorine atoms; a perfluoropolyether chain (PFPE chain) refers to a structure having two or more perfluoroalkyleneoxy units; and a "surface layer" refers to a layer formed on a substrate.

[0010] [Compound] A compound according to one embodiment of the present disclosure is a PFPE compound, a compound having a number-average molecular weight of 40,000 or more, and a compound that dissolves in an amount of 1 part by mass or more in 100 parts by mass of 1,1,1,2,2,3,3,4,4,5,5,6,6-tridecafluorohexane at 25° C. Hereinafter, 1,1,1,2,2,3,3,4,4,5,5,6,6-tridecafluorohexane will also be referred to as "CH," and the amount that dissolves in 100 parts by mass of CH at 25° C. will also be referred to as the "CH solubility amount."

[0011] As mentioned above, in recent years, there has been a demand for wet coating agents capable of forming high-strength surface layers, and high-molecular-weight PFPE compounds are desired. However, in the conventional method of photopolymerizing a compound having perfluoroalkyleneoxy units and carbonyl fluoride groups at both ends, a branched structure is formed, making it difficult to achieve high molecular weight. Specifically, in the photopolymerization of a compound having carbonyl fluoride groups at both ends, first, as represented by the following formula (5), the carbonyl fluoride group is removed to generate a carbonyl fluoride radical and a fluoroalkyl radical having a perfluoroalkyleneoxy unit. Then, as represented by the following formula (6), it is considered that the fluoroalkyl radicals of the generated radicals are bonded to each other to polymerize. Note that in formulas (5) and (6), Rf ３ is a structure having a perfluoroalkyleneoxy unit.

[0012]

[0013] On the other hand, as described in Patent Document 1, a fluoroalkyl radical bonds to the oxygen atom of another carbonyl fluoride group, as shown in the following formula (7), thereby radicalizing the carbon atom of the carbonyl group. Then, as shown in the following formula (8), it is thought that the radicalized carbon atom further bonds with another fluoroalkyl radical, thereby forming a branched structure. As a result, a PFPE compound having a carbonyl fluoride group at the end of the side chain is obtained. Note that in formulas (7) and (8), Rf ３ is Rf in the formulas (5) and (6). ３ is synonymous with.

[0014]

[0015] PFPE compounds having a carbonyl fluoride group at the end of the side chain have a three-dimensionally complex molecular structure, so that they are difficult to increase in molecular weight even when further irradiated with ultraviolet light. Furthermore, when a PFPE compound having a carbonyl fluoride group at the end of the side chain is further increased in molecular weight, a crosslinked structure is formed by the reaction of the end of the side chain, resulting in a PFPE compound with low solubility in solvents that is difficult to apply to wet coating agents.

[0016] In contrast, the present inventors have confirmed that, as described below, by irradiating a raw material compound having perfluoroalkyleneoxy units and at least one terminal group selected from the group consisting of a carboxy group and an alkyloxycarbonyl group under a flow of inert gas with ultraviolet light, a branched structure, as occurs when a compound having carbonyl fluoride groups at both ends is used as a raw material, is not produced. The obtained PFPE compound of this embodiment is a novel PFPE compound having a number-average molecular weight of 40,000 or more and a dissolved amount of CH of 1 part by mass or more. The PFPE compound of this embodiment has excellent solubility in solvents and is applicable to wet coating agents. In addition, due to its high molecular weight, a high-strength surface layer is formed when applied to a wet coating agent. The PFPE compound of this embodiment, which is difficult to obtain by conventional methods, can be obtained by a novel production method, as described below, in which a starting compound having one or more perfluoroalkyleneoxy units and at least one type selected from the group consisting of a carboxy group and an alkyloxycarbonyl group at a terminal thereof, wherein the average total number of carboxy groups and alkyloxycarbonyl groups present in one molecule is 1.90 to 2.00, is polymerized by irradiating the starting compound with ultraviolet light having a wavelength of 150 to 300 nm in a flow of inert gas. The novel production method for obtaining the PFPE compound of this embodiment will be described below.

[0017] <Number-average molecular weight> The number-average molecular weight of the PFPE compound according to one embodiment of the present disclosure is 40,000 or more, and from the viewpoint of obtaining a high-strength surface layer, it is preferably 50,000 or more, more preferably 100,000 or more, even more preferably 150,000 or more, and particularly preferably 200,000 or more. From the viewpoint of excellent solubility in solvents, the number-average molecular weight of the PFPE compound is preferably 250,000 or less.

[0018] In the present disclosure, the number average molecular weight of a compound can be determined by the following method. １９ F-NMR measurement １９ Obtain an F-NMR spectrum. Assuming that the compound to be measured does not have a branched structure, １９The number average molecular weight of the compound is calculated from the total amount of terminal groups (carboxy group, alkyloxycarbonyl group, perfluoroalkyl group, etc.) determined by F-NMR measurement.

[0019] <Dissolution Amount> From the viewpoint of application to a wet coating agent, the dissolution amount of CH of a PFPE compound according to an embodiment of the present disclosure is 1 part by mass or more, preferably 10 parts by mass or more, and more preferably 20 parts by mass or more. In the present disclosure, the dissolution amount of CH of a PFPE compound is a value determined by the following method. At 25°C, 1 g, 10 g, and 20 g of a PFPE compound are each added to 100 g of CH and stirred for 60 minutes to prepare mixtures. 10 g of the obtained mixture is added to 100 g of CH under 0.2 MPa of N ２ The gas is passed through a polytetrafluoroethylene (PTFE) filter with a diameter of 47 mm and a pore size of 5 μm under pressure, and the presence or absence of residue on the filter is confirmed after 1 to 30 minutes. If no residue is present on the filter, it is determined that the PFPE compound has completely dissolved in CH; if residue remains on the filter, it is determined that the PFPE compound has not completely dissolved.

[0020] <Perfluoropolyether Chain (PFPE Chain)> The PEPE compound according to one embodiment of the present disclosure has a PFPE chain. The PFPE chain has a structure in which two or more perfluoroalkyleneoxy units are repeated. The PFPE chain preferably does not have a side chain whose terminal is a highly reactive functional group (such as a carboxy group, an alkyloxycarbonyl group, or a carbonyl fluoride group), more preferably does not have a side chain, and even more preferably does not have a branched structure. The presence or absence of a branched structure in the PFPE chain can be determined by the following: １９ This is confirmed by F-NMR measurement.

[0021] An example of the PFPE chain is a structure represented by the following formula (3): -(R １３ O) ｎ１ -...Formula (3) In formula (3), R １３ are each independently a perfluoroalkylene group, and n1 is an integer of 130 or greater.

[0022] R １３The number of carbon atoms in R is preferably 1 to 6, more preferably 1 to 4, and particularly preferably 1 or 2, from the viewpoints of excellent fluidity and solubility, and excellent transparency depending on the application. １３ When R has 3 or more carbon atoms, it may be a linear perfluoroalkylene group, a branched perfluoroalkylene group, or a perfluoroalkylene group having a ring structure. １３ From the viewpoint of excellent fluidity, n1 R is preferably a linear perfluoroalkylene group or a branched perfluoroalkylene group, and more preferably a linear perfluoroalkylene group. １３ may be the same as or different from each other. In other words, the PFPE chain may have two or more types of (R １３ O). １３ O) means that two or more (R １３ O) is present, and two or more types of (R １３ O) is present.

[0023] R １３ Specific examples of the group include -CF ２ -, -CF ２ CF ２ -, -CF(CF ３ ) -, -CF ２ CF ２ CF ２ -, -CF(CF ３ )CF ２ -, -CF ２ CF ２ CF ２ CF ２ -, -CF(CF ３ )CF ２ CF ２ -, -CF ２ CF (CF ３ )CF ２ -, -CF ２ CF ２ CF ２ CF ２ CF ２ -, -CF(CF ３ )CF ２ CF２ CF ２ -, -CF ２ CF (CF ３ )CF ２ CF ２ -, -CF ２ CF ２ CF ２ CF ２ CF ２ CF ２ -, -CF(CF ３ )CF ２ CF ２ CF ２ CF ２ -, -CF ２ CF (CF ３ )CF ２ CF ２ CF ２ -, -CF ２ CF ２ CF (CF ３ )CF ２ CF ２ -, -cycloC ４ F ６ -, -cycloC ５ F ８ -, and -cycloC ６ F １０ - and combinations thereof.

[0024] Here, -cycloC ４ F ６ - means a perfluorocyclobutanediyl group. Examples of perfluorocyclobutanediyl groups include perfluorocyclobutane-1,2-diyl and perfluorocyclobutane-1,3-diyl groups. ５ F ８ - means a perfluorocyclopentanediyl group. Examples of perfluorocyclopentanediyl groups include perfluorocyclopentane-1,2-diyl and perfluorocyclopentane-1,3-diyl groups. ６ F １０- means a perfluorocyclohexanediyl group. Examples of the perfluorocyclohexanediyl group include a perfluorocyclohexane-1,2-diyl group, a perfluorocyclohexane-1,3-diyl group, and a perfluorocyclohexane-1,4-diyl group.

[0025] n1 is (R １３ O) and is, for example, 130 or more. From the viewpoint of achieving both a high-strength surface layer and good solubility in a solvent, it is preferably 300 to 2,000, more preferably 500 to 1,500, and even more preferably 800 to 1,300.

[0026] The PFPE chain is preferably represented by the following formula (3-1): -[(R ｆ１１ O) ｎ１１ (R ｆ１２ O) ｎ１２ (R ｆ１３ O) ｎ１３ (R ｆ１４ O) ｎ１４ (R ｆ１５ O) ｎ１５ (R ｆ１６ O) ｎ１６ ]- … (3-1) However, R ｆ１１ is a perfluoroalkylene group having one carbon atom, and R ｆ１２ is a perfluoroalkylene group having 2 carbon atoms, and R ｆ１３ is a perfluoroalkylene group having 3 carbon atoms, and R ｆ１４ is a perfluoroalkylene group having 4 carbon atoms, and R ｆ１５ is a perfluoroalkylene group having 5 carbon atoms, and R ｆ１６ is a perfluoroalkylene group having 6 carbon atoms. n11, n12, n13, n14, n15, and n16 each independently represent an integer of 0 or 1 or more, and n11 + n12 + n13 + n14 + n15 + n16 = n1.

[0027] In addition, (R ｆ１１ O) ~ (R ｆ１６ O) may be bonded in any order. n11 to n16 in formula (3-1) are each ｆ１１ O) ~ (R ｆ１６O), and does not represent the arrangement. For example, (R ｆ１５ O) ｎ１５ is (R ｆ１５ O) is n15, and (R ｆ１５ O) ｎ１５ Similarly, (R ｆ１１ O) ~ (R ｆ１６ The order of description of each unit does not represent the bonding order of the units.

[0028] Among them, -(R １３ O) ｎ１ - preferably includes at least one selected from the group consisting of structures represented by the following formulas (3-11) to (3-15), and more preferably includes a structure represented by formula (3-11). -(R ｆ１１ O) ｎ１１ - (R ｆ１２ O) ｎ１２ -...(3-11) -(R ｆ１２ O) ｎ１２ - (R ｆ１４ O) ｎ１４ -...(3-12) -(R ｆ１３ O) ｎ１３ - (R ｆ１５ O) ｎ１５ -...(3-13) -(R ｆ１１ O) ｎ１１ - (R ｆ１２ O) ｎ１２ - (R ｆ１３ O) ｎ１３ -...(3-14) -(R ｆ１２ O) ｎ１２ - (R ｆ１３ O) ｎ１３ - (3-15) where the symbols in equations (3-11) to (3-15) are the same as those in equation (3-1) above.

[0029] In formula (3-11), (R ｆ１１ O) and (R ｆ１２ O) and (R ｆ１３ O) and (R ｆ１４ O) can be bonded in any order. For example, (R ｆ１１ O) and (R ｆ１２ O) may be arranged alternately, and (R ｆ１１O) and (R ｆ１２ O) may be arranged in each block, and (R ｆ１１ O) and (R ｆ１２ O) and (R ｆ１３ O) and (R ｆ１４ O) may be arranged randomly. The same applies to formulas (3-12) to (3-15).

[0030] From the viewpoint of excellent thermal stability, chemical resistance, low surface energy, and electrical insulation, the molecular weight of the PFPE chain is preferably 95% or more of the molecular weight of the entire PFPE compound, more preferably 97% or more, and even more preferably 99% or more.

[0031] Examples of the terminal group of the PFPE compound include a fluorine atom, a carboxy group, and an alkyloxycarbonyl group. The PFPE compound may have a perfluoroalkylene group in addition to the PFPE chain and the terminal group. The PFPE compound preferably does not have a linking group such as an amide, urethane, ester, or carbonate, and is more preferably a compound consisting of a PFPE chain, a terminal group, and a perfluoroalkylene group. The PFPE compound represented by formula (1) described below consists only of a PFPE chain except for the terminal carboxyl group and alkyloxycarbonyl group, and does not have a linking group such as an amide, urethane, ester, or carbonate, and therefore has excellent thermal stability, chemical resistance, low surface energy, and electrical insulation.

[0032] <Formula (1)> An example of a PFPE compound according to an embodiment of the present disclosure is a compound represented by the following formula (1): T １１ -O-Rf １ -T １２ ...Formula (1) In formula (1), T １１ and T １２ are each independently -R １１ -F, -R １１ -COOH or -R １１ -COOR １２ and R １１ are each independently a perfluoroalkylene group, and R １２ are each independently an alkyl group, and Rf １ is (R １３ O) ｎ１and R １３ are each independently a perfluoroalkylene group, and n1 is an integer of 130 or greater.

[0033] Rf in formula (1) １ (R １３ O) ｎ１ is the above-mentioned (R １３ O) ｎ１ is synonymous with R １３ and n1 are the same as above. １１ The perfluoroalkylene group represented by the formula (I) is the same as the above-mentioned R １３ Examples include the same perfluoroalkylene groups as those represented by R １１ is n1 R １３ and n1 R １３ may be different from any of the n1 R １３ It is preferable that the two R １１ may be the same as or different from each other. １１ The number of carbon atoms in R is preferably 1 to 3, more preferably 1 or 2, and even more preferably 1, from the viewpoint of excellent fluidity and solubility, and excellent transparency depending on the application. １１ may be the same as or different from each other.

[0034] R １２ The alkyl group represented by the formula (I) is preferably a methyl group or an ethyl group, and a methyl group is more preferred in that it does not prevent the formation of a high molecular weight. １１ and T １２ All of these are -R １１ -COOR １２ When the two R １２ may be the same as or different from each other.

[0035] T in formula (1) １１ and T １２ are each independently -R １１ -F, -R １１ -COOH or -R １１ -COOR １２and from the viewpoint of ease of producing a high molecular weight substance, -R １１ In addition, T in formula (1) is preferred due to its high thermal stability. １１ and T １２ are each independently -R １１ It is also preferred that it is —F, and —R １１ -COOH and -R １１ The balance of the ratio of -F is important. Examples of the PFPE compound represented by formula (1) include the following compounds. １１ , Rf １ , and R １２ is as described above. １１ -O-Rf １ -R １１ -F F-R １１ -O-Rf １ -R １１ -COOH HOCO-R １１ -O-Rf １ -R １１ -COOH F-R １１ -O-Rf １ -R １１ -COOR １２ R １２ OCO-R １１ -O-Rf １ -R １１ -COOR １２

[0036] <Average number of specific functional groups in PFPE compound> In the PFPE compound according to one embodiment of the present disclosure, the number of carboxy groups (-COOH) and alkyloxycarbonyl groups (-COOR) present in one molecule is 1. １２ The average of the total number of carboxy groups and alkyloxycarbonyl groups present in one molecule is, for example, 1.6 or less, and may be 1.3 or less, 1.0 or less, 0.5 or less, or 0.2 or less. Hereinafter, the average of the total number of carboxy groups and alkyloxycarbonyl groups present in one molecule is also referred to as the "average number of specific functional groups."

[0037] In the present disclosure, the average number of specific functional groups of a compound is a value determined by the following method. １９It is determined by F-NMR. The carboxyl group and alkyloxycarbonyl group present at both ends and the non-reactive CF ３ It is a value calculated from the ratio of carboxy groups and alkyloxycarbonyl groups, assuming that the total of the groups is 2.0.

[0038] <Molecular Weight Distribution> The molecular weight distribution of the PFPE compound according to one embodiment of the present disclosure is not particularly limited, and is preferably, for example, 1.3 to 2.5. From the viewpoint of achieving both fluidity and surface layer strength, 1.3 to 2.0 is more preferable, and 1.3 to 1.7 is even more preferable. The polymerization method of the present disclosure is a sequential reaction of relatively stable fluoroalkyl radical ends, and it has been newly discovered that there is little broadening of the molecular weight distribution associated with increased molecular weight. In the present disclosure, the molecular weight distribution of the compound is a value expressed as Mw / Mn, where Mw is the weight average molecular weight measured by gel permeation chromatography (GPC) using polystyrene as the standard substance, and Mn is the number average molecular weight.

[0039] [Method for Producing Compound] A method for producing a compound according to one embodiment of the present disclosure is a method for producing a PFPE compound, comprising irradiating a raw material compound having one or more perfluoroalkyleneoxy units, having at least one type selected from the group consisting of a carboxy group and an alkyloxycarbonyl group at a terminal thereof, and having an average number of specific functional groups of 1.90 to 2.00 with ultraviolet light having a wavelength of 150 to 300 nm under a flow of inert gas, thereby polymerizing the raw material compound.

[0040] The manufacturing method of this embodiment produces a PFPE compound having a high molecular weight and excellent solubility in solvents, and is suitable for manufacturing the aforementioned PFPE compounds, i.e., PFPE compounds having a number-average molecular weight of 40,000 or more and a C6H solubility of 1 part by mass or more.

[0041] As described above, in the conventional method of photolyzing and coupling a compound having carbonyl fluoride groups at both ends, a branched structure is formed by the reaction of the generated fluoroalkyl radical with the carbonyl fluoride group, making it difficult to increase the molecular weight, and when the molecular weight is increased, a crosslinked structure is formed, resulting in a PFPE compound that is difficult to dissolve in a solvent. In contrast, in the production method of the present embodiment, a raw material compound having one or more perfluoroalkyleneoxy units, at least one selected from the group consisting of a carboxy group and an alkyloxycarbonyl group at the terminal, and an average specific functional group number of 1.90 to 2.00 is used, and ultraviolet light is irradiated under a flow of inert gas, thereby obtaining a PFPE compound with a high molecular weight and excellent solubility in a solvent.

[0042] Specifically, since the terminal of the raw material compound in this embodiment is not a carbonyl fluoride group but at least one selected from the group consisting of a carboxy group and an alkyloxycarbonyl group, the fluoroalkyl radical at the polymer terminal generated by the elimination of the carboxy group or alkyloxycarbonyl group as represented by the following formula (9) is unlikely to react with the carboxy group or alkyloxycarbonyl group in another molecule. Therefore, as represented by the following formula (10), polymerization by bonding between fluoroalkyl radicals proceeds, and the molecular weight is increased while maintaining a linear chain, so that a PFPE compound having excellent solubility in solvents can be obtained even with a high molecular weight. Note that in formulas (9) and (10), Rf ４ is a structure having a perfluoroalkyleneoxy unit.

[0043]

[0044] In addition, since the average number of specific functional groups of the raw material compound in this embodiment is equal to or greater than the lower limit, the proportion of compounds having only one carboxy group or one alkyloxycarbonyl group at their terminal is low compared to compounds having at least one type selected from the group consisting of a carboxy group and an alkyloxycarbonyl group at both terminals, making it less likely that polymerization will terminate due to lack of terminal reactivity. Therefore, it is believed that using a raw material compound having an average number of specific functional groups within the above range will make it easier to obtain a high molecular weight PFPE compound.

[0045] Furthermore, when the functional group at the terminal is a carboxy group, when ultraviolet light is irradiated without flowing an inert gas, it is thought that a carbonyl fluoride group is generated through a reaction between the fluoroalkyl radical and a hydroxyl radical generated by further decomposition of the eliminated carboxyl group, as represented by the following formula (11), and that a branched structure is easily formed. In contrast, in this embodiment, ultraviolet light is irradiated under a flow of inert gas, so that the generated hydroxyl radical is removed from the reaction system, making it difficult for a carbonyl fluoride group to be generated, and the molecular weight is increased while maintaining a linear chain structure.

[0046]

[0047] Furthermore, when the functional group at the terminal is an alkyloxycarbonyl group, if ultraviolet irradiation is performed without flowing inert gas, hydroxyl radicals are not generated, making it difficult to form a branched structure, but polymerization is difficult to proceed, making it difficult to obtain a high molecular weight PFPE compound.The reason why polymerization is difficult to proceed is unclear, but it is presumed that this is because the alkyl radicals generated by further decomposition of the detached alkyloxycarbonyl group add to the above-mentioned fluoroalkyl radicals, thereby terminating polymerization.In contrast, in this embodiment, ultraviolet irradiation is performed under flowing inert gas, so it is thought that the alkyloxy radicals or alkyl radicals produced as decomposition products volatilize out of the reaction system, making polymerization more likely to proceed and resulting in a high molecular weight.From the above, it is presumed that in this embodiment, a PFPE compound with a high molecular weight and excellent solubility in solvents can be obtained.

[0048] <Raw Material Compound> (Perfluoroalkyleneoxy Unit) The raw material compound used in the production method of this embodiment has one or more perfluoroalkyleneoxy units. An example of a structure composed of one or more perfluoroalkyleneoxy units is a structure represented by the following formula (4). -(R ２３ O) ｎ２ -...Formula (4) In formula (4), R ２３ are each independently a perfluoroalkylene group, and n2 is an integer of 1 to 75.

[0049] R ２３ The number of carbon atoms in R is preferably 1 to 6, more preferably 1 to 4, and even more preferably 1 or 2, from the viewpoint of obtaining a PFPE compound having excellent fluidity and solubility, and from the viewpoint of obtaining a PFPE compound having excellent transparency depending on the application of the PFPE compound. ２３ When R has 3 or more carbon atoms, it may be a linear perfluoroalkylene group, a branched perfluoroalkylene group, or a perfluoroalkylene group having a ring structure. ２３ is preferably a linear perfluoroalkylene group or a branched perfluoroalkylene group, more preferably a linear perfluoroalkylene group, from the viewpoint of obtaining a PFPE compound having excellent fluidity. ２３ may be the same as or different from each other. In other words, when n2 is 2 or more, the structure represented by formula (4) has two or more kinds of (R ２３ O). ２３ O) means that two or more (R ２３ O) is present, and two or more types of (R ２３ O) is present. ２３ Specific examples of the above include the above-mentioned R １３ Specific examples similar to those mentioned above are given.

[0050] n2 is an integer of 1 to 75, and is preferably 8 to 75, more preferably 18 to 75, and even more preferably 30 to 55, from the viewpoints of availability and ease of production of high molecular weight compounds.

[0051] The structure represented by formula (4) is preferably represented by the following formula (4-1): -[(R ｆ２１ O) ｎ２１ (R ｆ２２ O) ｎ２２ (R ｆ２３ O) ｎ２３ (R ｆ２４ O) ｎ２４ (R ｆ２５ O) ｎ２５ (R ｆ２６ O) ｎ２６ ] - (4-1) In the above formula (4-1), R ｆ２１ , R ｆ２２ , R ｆ２３ , R ｆ２４ , R ｆ２５ , and R ｆ２６ respectively represent R in the formula (3-1). ｆ１１ , R ｆ１２ , R ｆ１３ , R ｆ１４ , R ｆ１５ , and R ｆ１６ n21, n22, n23, n24, n25, and n26 each independently represent an integer of 0 or 1 or more, and n21 + n22 + n23 + n24 + n25 + n26 = n2.

[0052] In addition, (R ｆ２１ O) ~ (R ｆ２６ O) may be bonded in any order. n21 to n26 in formula (4-1) are each ｆ２１ O) ~ (R ｆ２６ O), and does not represent the arrangement.

[0053] Among them, -(R ２３ O) ｎ２ - preferably includes at least one selected from the group consisting of structures represented by the following formulas (4-11) to (4-15), and more preferably includes a structure represented by formula (4-11). -(R ｆ２１ O) ｎ２１ - (R ｆ２２ O)ｎ２２ -...(4-11) -(R ｆ２２ O) ｎ２２ - (R ｆ２４ O) ｎ２４ -...(4-12) -(R ｆ２３ O) ｎ２３ -...(4-13) -(R ｆ２１ O) ｎ２１ - (R ｆ２３ O) ｎ２３ -...(4-14) -(R ｆ２２ O) ｎ２２ - (R ｆ２３ O) ｎ２３ - (4-15) However, the symbols in the formulas (4-11) to (4-15) are the same as those in the above formula (4-1).

[0054] In formula (4-11), (R ｆ２１ O) and (R ｆ２２ O) can be bonded in any order. For example, (R ｆ２１ O) and (R ｆ２２ O) may be arranged alternately, and (R ｆ２１ O) and (R ｆ２２ O) may be arranged in each block, and (R ｆ２１ O) and (R ｆ２２ O) may be arranged randomly. The same applies to formulas (4-12) to (4-15).

[0055] The molecular weight of the structure represented by formula (4) is preferably 70% or more, more preferably 80% or more, and even more preferably 90% or more of the molecular weight of the entire raw material compounds, from the viewpoint of excellent thermal stability, chemical resistance, low surface energy, and electrical insulation.

[0056] The raw material compound used in the production method of this embodiment may have a perfluoroalkylene group in addition to the structure represented by formula (4) and at least one selected from the group consisting of a carboxy group and an alkyloxycarbonyl group as a terminal group. The raw material compound preferably does not have a linking group such as an amide, a urethane, an ester, or a carbonate, and is more preferably a compound consisting of the structure represented by formula (4), at least one selected from the group consisting of a carboxy group and an alkyloxycarbonyl group as a terminal group, and a perfluoroalkylene group.

[0057] (Terminal Functional Group and Average Number of Specific Functional Groups) The raw material compound used in the production method of this embodiment has at least one selected from the group consisting of a carboxy group and an alkyloxycarbonyl group at its terminal. The alkyl group contained in the alkyloxycarbonyl group is the same as R １２ The average number of specific functional groups in the raw material compound used in the production method of this embodiment, i.e., the average total number of carboxy groups and alkyloxycarbonyl groups present in one molecule, is 1.90 to 2.00, and from the viewpoint of obtaining a high molecular weight PFPE compound, it is preferably 1.95 to 2.00, and more preferably 1.97 to 2.00. The average number of specific functional groups in the raw material compound can be determined by the method described above.

[0058] Here, in raw material compounds having an average number of specific functional groups of less than 2.00, one end of the molecule is, for example, a non-reactive perfluoroalkyloxy group, rather than a carboxy group or an alkyloxycarbonyl group. Therefore, as the polymerization of the raw material compound progresses, the number of carboxy groups and alkyloxycarbonyl groups decreases, and only non-reactive end groups remain, which limits the maximum molecular weight. For example, if polymerization is carried out using a raw material compound having an average number of specific functional groups of 1.90 and a number-average molecular weight of 5,000, the theoretical maximum molecular weight is 100,000. Furthermore, if the average number of specific functional groups of the raw material compound is 1.95, and the number-average molecular weight of the raw material compound is 2,500, the theoretical maximum molecular weight is 100,000. Similarly, if the average number of specific functional groups of the raw material compound is 1.97, and the number-average molecular weight of the raw material compound is 1,500, the theoretical maximum molecular weight is 100,000. Thus, the closer the average number of specific functional groups of the raw material compound is to 2, the more likely it is that a high-molecular-weight PFPE compound with a molecular weight of 100,000 or more can be obtained, even if the raw material compound has a low molecular weight. In order to make the average number of specific functional groups of the raw material compound close to 2, separation and purification using a column may be carried out.

[0059] (Number Average Molecular Weight) From the viewpoint of availability and ease of producing a polymer, the number average molecular weight of the raw material compound is preferably 1,000 to 10,000, more preferably 2,000 to 7,000, and even more preferably 3,000 to 5,000. The number average molecular weight of the raw material compound is determined by the method described above.

[0060] (Formula (2)) The raw material compound preferably contains a molecule having a structure represented by the following formula (2): T ２１ -O-Rf ２ -T ２２ ...Formula (2) In formula (2), T ２１ and T ２２ are each independently -R ２１ -COOH or -R ２１ -COOR ２２ and R ２１ are each independently a perfluoroalkylene group, and R ２２are each independently an alkyl group, and Rf ２ is (R ２３ O) ｎ２ and R ２３ are each independently a perfluoroalkylene group, and n2 is an integer of 1 to 75.

[0061] Rf in formula (2) ２ (R ２３ O) ｎ２ is the above-mentioned (R ２３ O) ｎ２ is synonymous with R ２３ and n2 are the same as above. ２１ The perfluoroalkylene group represented by the formula (I) is the same as the above-mentioned R １３ The two R ２１ may be the same as or different from each other. ２２ Examples of the alkyl group represented by the formula (I) include a methyl or ethyl group, and a methyl group is preferred. ２１ and T ２２ All of these are -R ２１ -COOR ２２ When the two R ２２ may be the same as or different from each other.

[0062] When the raw material compound contains a molecule having a structure represented by formula (2), the raw material compound may contain a molecule having a structure other than that represented by formula (2), as long as the average number of specific functional groups satisfies the above-mentioned condition. ２１ and T ２２ At least one of the following is -R ２１ -F is exemplified. ２１ is T in formula (2) ２１ and T ２２ R included in ２１ The raw material compound is a compound having a structure represented by formula (2) and a compound having a structure represented by formula (2) in which T ２１ and T ２２ At least one of the following is -R ２１It is preferable that the compound contains a molecule having a structure in which -F is replaced by -F, and a molecule having a structure represented by formula (2) and a molecule having a structure in which T in formula (2) is replaced by -F. ２１ and T ２２ At least one of the following is -R ２１ It is more preferable that the structure is composed of a molecule in which the substituent is replaced by —F.

[0063] <Irradiation of ultraviolet rays> The wavelength of ultraviolet rays irradiated onto the raw material compound is 150 to 300 nm, and from the viewpoint of obtaining a PFPE compound having a high molecular weight and excellent solubility in a solvent, it is preferably 180 to 280 nm, more preferably 200 to 260 nm. The light source of ultraviolet rays is not particularly limited, and may be a high-pressure mercury lamp, a low-pressure mercury lamp, a metal halide lamp, an excimer lamp (Ar ２ , Kr ２ , Xe ２ , KrCl, KrF, ArF, F ２ Examples of suitable light sources include a metal halide lamp, a flash lamp, an electrodeless lamp, an LED lamp, etc. The light source of ultraviolet light can be selected appropriately depending on the wavelength of the ultraviolet light to be irradiated. Specifically, when the wavelength of the ultraviolet light is 250 to 300 nm, a metal halide lamp is used, when the wavelength is 185 nm or 254 nm, a low-pressure mercury lamp is used, and when the wavelength is 157 nm, a F ２ Excimer laser, Xe for 172 nm ２ Examples of such excimer lamps include an ArF excimer laser for 193 nm, a KrCl excimer lamp for 222 nm, and a KrF excimer laser for 248 nm.

[0064] The irradiation intensity of the ultraviolet light is, for example, 1 to 100 mW / cm ２ From the viewpoint of obtaining a PFPE compound having a high molecular weight and excellent solubility in a solvent, the range of 5 to 30 mW / cm ２ is preferred, and 10 to 20 mW / cm ２The irradiation intensity of ultraviolet light is measured using an ultraviolet integrating actinometer. The irradiation time of ultraviolet light varies depending on the molecular weight of the target PFPE compound, etc., and may be, for example, 1 to 100 hours. From the viewpoint of balancing energy cost and a high molecular weight of the PFPE compound, 5 to 50 hours is preferred, and 10 to 20 hours is more preferred. The irradiation dose of ultraviolet light varies depending on the molecular weight of the target PFPE compound, etc., and may be, for example, 1 to 2,000 J / cm. ２ From the viewpoint of balancing energy cost and a high molecular weight of the PFPE compound, 10 to 1,000 J / cm ２ is preferred, and 20 to 500 J / cm ２ is more preferred.

[0065] The ultraviolet irradiation is carried out under a flow of an inert gas. The flow of the inert gas is carried out by introducing the inert gas into the reactor. When the raw material compound is a liquid, the inert gas may be introduced (e.g., by bubbling) into the raw material compound (i.e., the liquid phase) in the reactor, or may be introduced into the gas phase in contact with the raw material compound. Examples of the inert gas include nitrogen gas, helium gas, neon gas, and argon gas. Nitrogen gas or helium gas is preferred, and nitrogen gas is preferred from the viewpoint of keeping costs low. From the viewpoint of suppressing the generation of carbonyl fluoride groups, the flow rate of the inert gas is preferably 0.1 L / min or more, more preferably 0.5 L / min or more, and even more preferably 1 L / min or more. The upper limit of the flow rate of the inert gas is not particularly limited, and may be, for example, 10 L / min. The flow rate of the inert gas is preferably 0.1 to 10 L / min, more preferably 0.5 to 10 L / min, and even more preferably 1 to 10 L / min.

[0066] It is preferable to irradiate the raw material with ultraviolet light while stirring it, in order to suppress the generation of carbonyl fluoride groups. For example, it is preferable to efficiently remove the generated carboxyl radicals and their decomposition products, such as hydroxyl radicals, from the reaction system by stirring. It is also preferable to renew the ultraviolet irradiation surface by stirring in order to efficiently carry out the reaction. The stirring means is not particularly limited, and examples thereof include a stirrer, a stirring blade, a mixer, etc.

[0067] The irradiation of the raw material compound with ultraviolet rays may be carried out by irradiating the raw material compound containing no solvent with ultraviolet rays, or by irradiating a mixture of the raw material compound and a fluorine-containing solvent with ultraviolet rays. In particular, when the viscosity of the raw material compound is high, it is preferable to add a fluorine-containing solvent to reduce the viscosity and then irradiate with ultraviolet rays, from the viewpoint of suppressing the generation of carbonyl fluoride groups. Alternatively, after starting the irradiation with ultraviolet rays without adding a fluorine-containing solvent to the raw material compound, a fluorine-containing solvent may be added when the viscosity of the raw material compound increases, to reduce the viscosity and further irradiate with ultraviolet rays.

[0068] The fluorine-containing solvent is preferably one that dissolves a high-molecular-weight PFPE compound and has low activity against the generated fluoroalkyl radicals. Furthermore, in order to pass an inert gas through the solvent, the boiling point of the fluorine-containing solvent is preferably higher than the temperature of the raw material compound (i.e., the reaction temperature) during UV irradiation. Specific examples of the fluorine-containing solvent include perfluorodecalin, perfluorotributylamine, Fomblin Y series (manufactured by Solvay), Galden (manufactured by Solvay), 1H-perfluorodecane, and other fluoroalkanes.

[0069] The temperature of the raw material compound during irradiation with ultraviolet light can be, for example, 0 to 150°C, and is preferably 50 to 100°C from the viewpoint of facilitating the photopolymerization and suppressing side reactions. The pressure inside the reactor during irradiation with ultraviolet light is, for example, slightly increased because the reaction is usually carried out under a flow of inert gas, but when a solvent is used, it may be increased to a gauge pressure of 0.1 MPa or less to suppress its volatilization. This is also preferred in that it suppresses the generation of carbonyl fluoride even under reduced pressure. The photopolymerization of the raw material compound by irradiation with ultraviolet light may be carried out by a batch method or a continuous method.

[0070] [Composition] A composition according to an embodiment of the present disclosure includes the above-described PFPE compound and a fluorinated solvent. The content of the above-described PFPE compound is preferably 0.001 to 30% by mass, more preferably 0.01 to 10% by mass, and even more preferably 0.1 to 5% by mass, based on the total mass of the composition.

[0071] Examples of fluorine-containing solvents include fluorine-based organic solvents. Examples of fluorine-based organic solvents include fluorinated alkanes, fluorinated aromatic compounds, fluoroalkyl ethers, fluorinated alkylamines, fluoroalcohols, and hydrofluoroolefins (HFOs). Specific examples of fluorinated alkanes are preferably compounds having 4 to 8 carbon atoms. Commercially available products include C ６ F １３ H (manufactured by AGC, Asahiklin (registered trademark) AC-2000), C ６ F １３ C ２ H ５ (AGC, Asahiklin (registered trademark) AC-6000), C ２ F ５ CHFCHFCF ３ (Vertrel (registered trademark) XF, manufactured by Chemours) and the like. Examples of fluorinated aromatic compounds include hexafluorobenzene, trifluoromethylbenzene, perfluorotoluene, and bis(trifluoromethyl)benzene.

[0072] As the fluoroalkyl ether, a compound having 4 to 12 carbon atoms is preferred. Commercially available products include CF ３ CH ２ OCF ２ CF ２ H (manufactured by AGC, Asahiklin (registered trademark) AE-3000), C ４ F ９ OCH ３ (3M Novec (registered trademark) 7100), C ４ F ９ O.C. ２ H ５ (3M Novec (registered trademark) 7200), C ２ F ５ CF (OCH ３ ) C ３ F ７(Novec (registered trademark) 7300, manufactured by 3M Corporation). Examples of fluorinated alkylamines include perfluorotripropylamine and perfluorotributylamine. Examples of HFOs include 1-chloro-2,3,3-trifluoro-1-propene (HCFO-1233yd). Commercially available products include Amorea (registered trademark) AS-300, manufactured by AGC.

[0073] In addition to the PFPE compound and fluorine-containing solvent, the composition may contain other components within a range that does not impair the effects of the present disclosure. Examples of other components include known additives such as aminosilanes, isocyanates, and epoxies. The aminosilanes, isocyanates, and epoxies have the effect of increasing the adhesion of the composition to a substrate on which it is coated.

[0074] The present disclosure will be described in detail below using examples. However, the present disclosure is not limited to these examples. Examples 1 to 3 are working examples, and Examples 4 and 5 are comparative examples.

[0075] [Example 1] While stirring 20 g of raw material compounds at 90°C under a nitrogen gas flow of 1.0 L / min, ultraviolet light having a wavelength of 254 nm was irradiated at an intensity of 15 mW / cm. ２ The mixture was irradiated with light for 14 hours (using a low-pressure mercury lamp (manufactured by Sen Special Light Sources Co., Ltd.)) to obtain PFPE compound (1-1). Raw material compound: a compound containing molecules of the structure represented by the following formula (2-1), having a number average molecular weight of 3,800 and an average number of specific functional groups of 1.97 (manufactured by Solvay, Fomblin ZDIAC4000). The average value of n21 was 20, and the average value of n22 was 20. HOCOCF ２ -O-(CF ２ O) ｎ２１ (CF ２ CF ２ O) ｎ２２ -CF ２ COOH...(2-1)

[0076] [Example 2] The PFPE compound (1-1) obtained in Example 1 was diluted with perfluorodecalin (PFD) to prepare a 20% by mass solution, and the solution temperature was adjusted to 60°C, and the solution was further irradiated with ultraviolet light for 6 hours while stirring. The viscosity increased, and a PFD solution of PFPE compound (1-2) was obtained. The PFD was removed by heating, thereby obtaining PFPE compound (1-2).

[0077] [Example 3] Under a nitrogen gas flow of 2.0 L / min at 90°C, 20 g of the same starting compound as in Example 1 was irradiated with ultraviolet light at the same wavelength and irradiation intensity as in Example 1 for 13 hours while stirring, thereby obtaining a PFPE compound. The PFPE compound obtained by 13 hours of ultraviolet light irradiation was diluted with a fluorinated solvent, Fomblin-Y06 (manufactured by Solvay), to obtain a 10 mass% solution, and then further irradiated with ultraviolet light for 3 hours while stirring at 90°C, resulting in a gel, and a Fomblin-Y06 solution of PFPE compound (1-3) was obtained. The solution was washed with Asahiklin (registered trademark) AE3000 (manufactured by AGC), and then Fomblin-Y06 was extracted and removed, thereby obtaining PFPE compound (1-3).

[0078] Example 4 UV irradiation was carried out in the same manner as in Example 1, except that nitrogen gas flow and stirring were not carried out and the irradiation time was set to 111 hours, to obtain a PFPE compound (C-1).

[0079] Example 5 UV irradiation was carried out in the same manner as in Example 1, except that nitrogen gas flow and stirring were not carried out and the irradiation time was changed to 204 hours, to obtain a PFPE compound (C-2).

[0080] [Measurement] (Confirmation of branched structure) The PFPE compounds obtained in Examples 1 to 5 １９ F-NMR measurement １９ F-NMR spectra were obtained to confirm the presence or absence of peaks derived from branched structures. １９ Since no peaks attributable to a branched structure were detected in the F-NMR spectrum, it is believed that the compound does not have a branched structure. １９ A slight peak due to a branched structure was detected in the F-NMR spectrum, but it did not increase with time.

[0081] (Number average molecular weight) For the PFPE compounds obtained in Examples 1 to 5, １９ The number of terminal carboxyl groups and perfluoroalkyl groups was determined by F-NMR measurement, and the number average molecular weight was calculated assuming that the PFPE compound had no branched structure. The results are shown in Table 1 ("Mn" in the table).

[0082] (Molecular weight distribution) The PFPE compounds obtained in Examples 1 and 2 were measured by gel permeation chromatography (GPC), and the molecular weight distribution Mw / Mn was calculated from the weight average molecular weight Mw and number average molecular weight Mn determined using polystyrene as a standard substance. The results are shown in Table 1 ("Mw / Mn" in the table). In the table, "-" means that the measurement was omitted.

[0083] (terminal group) １９ The terminal groups of the PFPE compounds obtained in Examples 1 to 5 were identified by F-NMR analysis, and the carboxyl groups and CF ３ The average number of specific functional groups ("COOH number" in the table) was calculated from the proportion of carboxy groups, assuming that the total number of specific functional groups was 2.0. The results are shown in Table 1. Furthermore, the average total number of carbonyl fluoride groups present in one molecule was calculated using the same method as for the average number of specific functional groups. The results are shown in Table 1 ("COF number" in the table).

[0084] (C6H Solubility) 1 g, 10 g, and 20 g of the PFPE compounds obtained in Examples 1 to 5 were added to 100 g of C6H at 25° C. and stirred for 60 minutes to prepare mixtures. 10 g of the resulting mixtures were added to N ２ The solution was passed through a PTFE filter with a diameter of 47 mm and a pore size of 5 μm under gas pressure, and the presence or absence of residue on the filter was confirmed after 1 to 30 minutes. If no residue was present on the filter, it was determined that the PFPE compound had completely dissolved in CH, and if residue remained on the filter, it was determined that the PFPE compound had not completely dissolved and was not dissolved. The results are shown in Table 1 ("CH solubility" in Table 1). In Table 1, "A" indicates that the compound was dissolved, and "B" indicates that the compound was not uniformly dissolved.

[0085]

[0086] As shown in Table 1, it was confirmed that the PFPE compounds obtained in Examples 1 to 3 had higher molecular weights and better solubility in solvents than the PFPE compounds obtained in Examples 4 and 5. Because the PFPE compounds obtained in Examples 1 to 3 have high molecular weights and excellent solubility in solvents, they are applicable to wet coating agents, and when applied to a wet coating agent, a high-strength surface layer is formed.

[0087] This shows that the method of the present disclosure can efficiently produce a high molecular weight product. If a raw material having a larger average number of specific functional groups than that of Example 1 is used, an even higher molecular weight product can be obtained.

[0088] On the other hand, in Examples 4 and 5, in which an inert gas was not passed through, -COOH contained in the raw material compound was not detected in the identification of the end group, but -COF was detected, which suggests that -COOH was converted to -COF. From the results of Examples 4 and 5, it can be seen that when an inert gas was not passed through, even when ultraviolet irradiation was carried out for a time 10 times longer than in Example 1, the polymerization did not proceed, and only a PFPE compound with a lower molecular weight than in Example 1, i.e., a molecular weight of less than 40,000, was obtained. From this, it is speculated that a compound in which -COOH in the raw material compound was converted to -COF has lower reactivity than the raw material compound before conversion, and therefore it is difficult to increase the molecular weight.

[0089] The compounds and compositions of the present disclosure, as well as compounds obtained by the methods for producing the compounds of the present disclosure, are useful as wet coating agents, which are used, for example, as water repellents for glass surfaces, antifouling coating agents, protective coating agents for electronic circuit boards, lubricants for magnetic recording media, and waterproofing agents for various devices.

[0090] The disclosure of Japanese Patent Application No. 2024-050200, filed on March 26, 2024, is incorporated herein by reference in its entirety. In addition, all documents, patent applications, and technical standards described herein are incorporated herein by reference to the same extent as if each individual document, patent application, and technical standard was specifically and individually indicated to be incorporated by reference.

Claims

1. A compound having a perfluoropolyether chain and a number average molecular weight of 40,000 or more, which dissolves at 25°C in 1,1,1,2,2,3,3,4,4,5,5,6,6-tridecafluorohexane at a rate of 1 part by mass or more in 100 parts by mass.

2. The compound according to claim 1, which is a compound represented by the following formula (1): T １１ -O-Rf １ -T １２ ...Formula (1) In formula (1), T １１ and T １２ are each independently -R １１ -F, -R １１ -COOH or -R １１ -COOR １２ and R １１ are each independently a perfluoroalkylene group, and R １２ are each independently an alkyl group, and Rf １ is (R １３ O) ｎ１ and R １３ are each independently a perfluoroalkylene group, and n1 is an integer of 130 or greater.

3. A composition comprising the compound according to claim 1 or 2 and a fluorine-containing solvent.

4. A method for producing a compound having a perfluoropolyether chain, comprising: irradiating a raw material compound having one or more perfluoroalkyleneoxy units and at least one type selected from the group consisting of a carboxy group and an alkyloxycarbonyl group at a terminal thereof, wherein the average total number of carboxy groups and alkyloxycarbonyl groups present in one molecule is 1.90 to 2.00, with ultraviolet light having a wavelength of 150 to 300 nm in a flow of inert gas, thereby polymerizing the raw material compound.

5. The method for producing a compound according to claim 4, wherein the raw material compound contains a molecule having a structure represented by the following formula (2): ２１ -O-Rf ２ -T ２２ ...Formula (2) In formula (2), T ２１ and T ２２ are each independently -R ２１ -COOH or -R ２１ -COOR ２２ and R ２１ are each independently a perfluoroalkylene group, and R ２２ are each independently an alkyl group, and Rf ２ is (R ２３ O) ｎ２ and R ２３ are each independently a perfluoroalkylene group, and n2 is an integer of 1 to 75.

6. The method for producing a compound according to claim 4, wherein the irradiation of the raw material compound with ultraviolet light is carried out by irradiating a mixture of the raw material compound and a fluorine-containing solvent with ultraviolet light.

7. The method for producing a compound according to claim 5, wherein the irradiation of the raw material compound with ultraviolet light is carried out by irradiating a mixture of the raw material compound and a fluorine-containing solvent with ultraviolet light.

8. The method for producing a compound according to any one of claims 4 to 7, wherein the temperature of the raw material compound during irradiation with ultraviolet light is 0 to 150°C.

Images