membrane

Abstract

An anion exchange membrane obtainable by curing a curable composition, the curable composition comprising a component (a) comprising a compound (A) and / or a compound (B) and / or a compound (C); wherein (A) is independently a 4-, 5-, 6-, or 7-membered non-aromatic bicyclic structure containing two optionally substituted nitrogen atoms; each of the rings contains a nitrogen atom which may be a bridgehead position; each of the nitrogen atoms is optionally substituted with hydrogen, C 1~3 Alkyl, C 5~6 (B) has one or two groups independently selected from cycloalkyl and vinylbenzyl attached thereto, provided that the compound contains at least two vinylbenzyl groups; (B) has one optionally substituted nitrogen atom and a C containing a nitrogen atom as a substituent to the ring. 1~6 and a 5-, 6-, or 7-membered non-aromatic heterocycle containing an alkyl group; and a nitrogen atom of the non-aromatic heterocycle is hydrogen, C 1~3 Alkyl, C 5~6 (C) is an optionally substituted, independently 4-, 5-, or 6-membered non-aromatic spirocyclic ring structure containing two nitrogen atoms; each of said rings contains at least one nitrogen atom which may be a bridgehead position; each of said nitrogen atoms is bonded to a hydrogen atom, C 1~3 Alkyl, C 5~6 The membrane of any of the preceding claims, wherein the compound has attached thereto one or two groups independently selected from cycloalkyl and vinylbenzyl, with the proviso that the compound contains at least two vinylbenzyl groups.

Description

[Technical Field]

[0001] This invention relates to ion exchange membranes, particularly anion exchange membranes (AEMs), their preparation processes, and their uses. [Background technology]

[0002] Ion exchange membranes are used in electrodialysis, electrolysis, acid and base production, and numerous other processes. Typically, ion transport across the membrane occurs under the influence of a driving force such as a potential gradient.

[0003] Some ion-exchange membranes contain a porous support, which provides mechanical strength. Such membranes are often called "composite membranes" because they contain both a polymer with ionic charge that identifies ions with opposite charges and a porous support that provides mechanical strength.

[0004] BPMs are commonly used for the production of acids and bases, for example, in a process called bipolar electrodialysis (BPED). BPMs have both a cationic or anion-exchange layer (AEL) and an anionic or cation-exchange layer (CEL), thus possessing both negatively charged and positively charged layers.

[0005] In the BPED process, acids and bases are generated at the BPM boundary by the dissociation reaction of water (WDR). + and OH -The ions pass through the corresponding ion exchange layers toward the cathode and anode, respectively. The BPED process is performed in a bipolar electrodialysis stack that includes monopolar anion exchange and monopolar cation exchange membranes in addition to the bipolar membrane. In the bipolar electrodialysis stack, the monopolar cation and anion exchange membranes are responsible for selectively separating the salt ions of the feed stream by their charge. The salt anions then combine with H+ formed by the WDR to form an acid, and the salt cations combine with OH- to form a base. For example, if NaCl is used in the feed stream, the monopolar membrane will be... - From Na + By separating them, NaOH and HCl are formed.

[0006] To generate high concentrations of acids and bases, it is crucial that the monopolar membrane has very high pH stability and durability (high pH stability and durability extend the membrane's lifespan). High efficiency in the process for generating acids and bases is also desirable. This is because H + and OH - To prevent ions from reaching the wrong channel, recombining, and leading to product loss, the membrane needs to have very high permeability selectivity. In particular, for anion exchange membranes, achieving high proton blocking performance at high concentrations is difficult due to the small size of protons.

[0007] WO2020 / 058665 describes porous cationic membranes for detecting, filtering, and / or purifying biomolecules. [Prior art documents] [Non-patent literature]

[0008] [Non-Patent Document 1] WO2020 / 058665 [Overview of the Initiative] [Problems to be Solved by the Invention]

[0009] An object of the present invention is to provide an anion exchange membrane that is mechanically strong, has high stability at a very low pH value, and has high permeation selectivity at a high acid concentration. [Means for Solving the Problems]

[0010] According to a first aspect of the present invention, there is provided an anion exchange membrane obtainable by curing a curable composition, the curable composition comprising a component (a) comprising a compound (A) and / or a compound (B) and / or a compound (C), (A) is a non-aromatic bicyclic structure containing two nitrogen atoms, which may be optionally substituted, the rings of the non-aromatic bicyclic structure are independently 4, 5, 6 or 7-membered; each of the rings contains a nitrogen atom, and the nitrogen atom may be at a bridgehead position; to each of the nitrogen atoms, one or two groups independently selected from hydrogen, C 1~3 alkyl, C 5~6 cycloalkyl, and vinylbenzyl are bonded, provided that the compound contains at least two vinylbenzyl groups; (B) is a 5, 6 or 7-membered non-aromatic heterocyclic ring containing one nitrogen atom and a C 1~6 alkyl group containing a nitrogen atom as a substituent on the ring; to the nitrogen atom of the non-aromatic heterocyclic ring, one or two groups independently selected from hydrogen, C 1~3 alkyl, C 5~6 cycloalkyl, and vinylbenzyl are bonded, provided that the compound contains at least two vinylbenzyl groups; (C) is an optionally substituted non-aromatic spiro ring structure containing two nitrogen atoms, the rings of the non-aromatic spiro ring structure are independently 4, 5 or 6-membered; Each of the rings contains at least one nitrogen atom, which may be located at the bridgehead position; Each of the nitrogen atoms is a hydrogen atom, C 1~3 Alkyl, C 5~6 The anion exchange membrane is provided, wherein one or two groups independently selected from cycloalkyl and vinylbenzyl are bonded to the compound, provided that the compound contains at least two vinylbenzyl groups.

[0011] In this document (including its claims), the verb “includes” and its conjugations are used in their non-restrictive sense, meaning that the items following the word are included, but not excluded from items not specifically mentioned. In addition, references to elements with the indefinite article “a” or “an” do not exclude the possibility of more than one of the elements being present unless the context clearly requires the presence of one or only one element. Thus, the indefinite article “a” or “an” usually means “at least one.” Component (a) of the curable composition may contain more than one compound selected from compound (A), compound (B), and / or compound (C). When referred to as component (a), it means all compounds that form part of component (a). “Optionally substituted” means that the compound contains optionally substituted substituents. The vinylbenzyl group is a CH2=CHC6H4CH2*- group, where the asterisk signifies a bond to other parts of the molecule.

[0012] The optional substituents in compounds (A), (B), and (C) are preferably C 1~3 It is alkyl. Component (a) of the curable composition has the function of a crosslinking agent. Preferably, the mole fraction of component (a) relative to all curable components of the curable composition is at least 0.90.

[0013] Preferably, at least one of the nitrogen (N) atoms in component (a) is a quaternary compound, and more preferably, at least two of the nitrogen atoms are quaternary compounds. If more than one compound is present in component (a), preferably all compounds in component (a) contain at least one quaternary nitrogen atom, and more preferably, at least two of the nitrogen atoms are quaternary compounds. The nitrogen atoms are non-aromatic, i.e., not part of an aromatic heterocycle. Preferably, the ratio of N to vinylbenzyl groups in the quaternary compound is at least 1:3, more preferably at least 1:2, for example 1:2 or 2:3. Preferably, the ratio of N to vinylbenzyl groups in the quaternary compound is at most 2:1, more preferably at most 3:2, for example 1:1. In one embodiment, component (a) contains two nitrogen atoms and two vinylbenzyl groups.

[0014] Component (a) (i.e., each of the compounds forming part of component (a)) preferably has a molecular weight of less than 700 Da, more preferably less than 600 Da, and particularly less than 550 Da. By maintaining a low molecular weight of compound (a), the ion exchange capacity of the AEM of the present invention is suitable for most applications.

[0015] Examples of compounds that can be used as component (a) include the following compounds AXL3-1 to AXL3-23.

[0016] [ka]

[0017] [ka]

[0018] [ka]

[0019] [ka]

[0020] [ka]

[0021] [ka]

[0022] The curable composition preferably comprises 65 to 85 wt% of component (a), more preferably 65 to 75 wt% of component (a), and in one embodiment, 70 to 75 wt% of component (a). In one embodiment, an anion exchange membrane according to a first aspect of the present invention contains at least 1 ppm of monomer(a) (typically as a result of incomplete curing when the membrane is formed), preferably at least 10 ppm, and more preferably at least 100 ppm of monomer(a). Preferably, the anion exchange membrane contains less than 20,000 ppm of component(a), more preferably less than 10,000 ppm of component(a). Component(a) means the sum of all compounds that make up component(a).

[0023] The curable composition optionally further comprises a monomer containing a cationic group and one or only one curable ethylenically unsaturated group as component (b). Preferably, the curable composition does not contain component (b), or the curable composition contains a small amount of component (b), for example, the curable composition preferably contains 0 to 10 wt% of component (b), more preferably 0 to 7 wt% of component (b).

[0024] Component (b) may contain one or more monomers, each containing a cationic group and one or more curable ethylenically unsaturated groups. In component (b), the group having a cationic charge is preferably a quaternary ammonium group. The one and only curable ethylenically unsaturated group present in component (b) is preferably a vinyl or allyl group, and more preferably a vinyl group.

[0025] In one embodiment, component (b) has formula (SM), where R 1 , R 2 and R 3 Each of these independently represents an alkyl group or an aryl group, or R 1 , R 2 and R 3 Two or three of these, along with the positively charged nitrogen atom to which they are bonded, form a optionally substituted five or six-membered ring; n3 represents an integer from 1 to 3; X3 Θ represents an anion, preferably a chloride ion, bromide ion, iodide ion, or hydroxide ion.

[0026] [ka]

[0027] Examples of component (b) in formula (SM) include the following compounds:

[0028] [ka]

[0029] The above ingredients can be prepared, for example, as described in US2016 / 177006. The curable composition optionally further comprises a radical initiator as component (c). Preferred radical initiators include thermal initiators, photoinitiators, and combinations thereof.

[0030] The curable composition preferably contains 0 to 10 wt% of a radical initiator, more preferably 0 to 3 wt% of a radical initiator. When the curable composition is cured using ultraviolet light, visible light, or thermally, the curable composition preferably contains 0.001 to 2 wt%, particularly 0.005 to 1.5 wt% of a radical initiator.

[0031] Examples of suitable thermal initiators that can be used as component (c) include 2,2'-azobis(2-methylpropionitrile) (AIBN), 4,4'-azobis(4-cyanovaleric acid), 2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azobis(2-methylbutyronitrile), 1,1'-azobis(cyclohexane-1-carbonitride), and 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile). Nitrile), dimethyl 2,2'-azobis(2-methylpropionate), 2,2'-azobis[N-(2-propenyl)-2-methylpropionamide, 1-[(1-cyano-1-methylethyl)azo]formamide, 2,2'-azobis(N-butyl-2-methylpropionamide), 2,2'-azobis(N-cyclohexyl-2-methylpropionamide), 2,2'-azobis(2-methylpropionamide) 2,2'-Azobis[2-(2-imidazolin-2-yl)propane]dihydrochloride, 2,2'-Azobis[2-(2-imidazolin-2-yl)propane]disulfate dihydrate, 2,2'-Azobis[N-(2-carboxyethyl)-2-methylpropionamidine]hydrate, 2,2'-Azobis{2-[1-(2-hydroxyethyl)-2-imidazolin-2-yl]propane}dihydrochloride, 2,2'-Azobis{2-[1-(2-hydroxyethyl)-2-imidazolin-2-yl]propane}dihydrochloride, 2,2'-Azobis[2-[1-(2-hydroxyethyl)-2-imidazolin-2-yl]propane]dihydrochloride, 2,2'-Azobis[2-[1-(2-hydroxyethyl)-2-imidazolin-2-yl]propane]dihydrochloride, 2,2'-Azobis[2-(2-imidazolin-2-yl)propane]dihydrochloride, 2,2'-Azobis[2-(2-imidazolin-2-yl)propane]disulfate dihydrate, 2,2'-Azobis[N-(2-carboxyethyl)-2-methylpropionamidine]hydrate, 2,2'-Azobis{2-[1-(2-hydroxyethyl)-2-imidazolin-2-yl]propane}dihydrochloride, 2,2'-Azobis[2-(2-imidazolin-2-yl)propane]dihydrochloride, 2,2'-Azobis[2-(2-imidazolin-2-yl)propane]disulfate dihydrate, 2,2'-Azobis[N-(2-carboxyethyl)-2-methylpropionamidine]hydrate, 2,2'-Azobis{2-[1-(2-hydroxyethyl)-2- Examples include hydrochloride, 2,2'-azobis[2-(2-imidazolin-2-yl)propane], 2,2'-azobis(1-imino-1-pyrrolidino-2-ethylpropane)dihydrochloride, 2,2'-azobis{2-methyl-N-[1,1-bis(hydroxymethyl)-2-hydroxyethyl]propionamide}, and 2,2'-azobis[2-methyl-N-(2-hydroxyethyl)propionamide].

[0032] Examples of suitable photoinitiators that may be included as component (c) in the curable composition include aromatic ketones, acylphosphine compounds, aromatic onium salt compounds, organic peroxides, thio compounds, hexaarylbiimidazole compounds, ketoxime ester compounds, boric acid compounds, azinium compounds, metallocene compounds, active ester compounds, compounds having a carbon-halogen bond, and alkylamine compounds. Preferred examples of aromatic ketones, acylphosphine oxide compounds, and thio compounds include compounds having a benzophenone skeleton or a thioxanthone skeleton as described in "RADIATION CURING IN POLYMER SCIENCE AND TECHNOLOGY", pp. 77-117 (1993).More preferred examples of these include the alpha-thiobenzophenone compounds described in JP1972-6416B (Japanese Patent Publication No. 47-006416), the benzoin ether compounds described in JP1972-3981B (Japanese Patent Publication No. 47-003981), the alpha-substituted benzoin compounds described in JP1972-22326B (Japanese Patent Publication No. 47-022326), and JP1972-23664B (Japanese Patent Publication No. 4 Benzoin derivatives as described in 7-023664), aroylphosphonic acid esters as described in JP1982-30704A (JP A 57-030704), dialkoxybenzophenones as described in JP1985-26483B (JP K 60-026483), and as described in JP1985-26403B (JP K 60-026403) and JP1987-81345A (JP A 62-081345) Benzoin ether, alpha-aminobenzophenone as described in JP1989-34242B (JP1989-34242), US4,318,791A, and EP0284561A1, p-di(dimethylaminobenzoyl)benzene as described in JP1990-211452A (JP1990-211452), and thiobenzoyl as described in JP1986-194062A (JP1986-194062). Examples include convertible aromatic ketones, acylphosphine sulfides described in JP1990-9597B (Japanese Patent Publication No. 02-009597), acylphosphines described in JP1990-9596B (Japanese Patent Publication No. 02-009596), thioxanthones described in JP1988-61950B (Japanese Patent Publication No. 63-061950), and coumarins described in JP1984-42864B (Japanese Patent Publication No. 59-042864). In addition, photoinitiators described in JP2008-105379A and JP2009-114290A are also preferred. Furthermore, photoinitiators described on pages 65-148 of "Ultraviolet Curing System" by Kato Kiyomi (published in 1989 by Research Center Co., Ltd.) may also be used.

[0033] Particularly preferred photoinitiators include Nourish type II photoinitiators that have an absorption maximum at wavelengths longer than 380 nm when measured at a temperature of 23°C in one or more solvents of water, ethanol, and toluene. Examples include photoinitiators derived from xanthenes, flavins, curcumin, porphyrins, anthraquinones, phenoxazines, camphaquinones, phenazines, acridines, phenothiazines, xanthones, thioxanthones, thioxanthenes, acridones, flavones, coumarins, fluorenones, quinolines, quinolones, naphthoquinones, quinolinones, arylmethanes, azos, benzophenones, carotenoids, cyanines, phthalocyanines, dipyrines, squarine, stilbenes, styryls, triazines, or anthocyanins.

[0034] Optionally, the curable composition further comprises a monomer that does not contain a cationic charge group, preferably a monomer containing at least two curable ethylenically unsaturated groups as component (d).

[0035] Preferably, the curable composition contains 0 to 5 wt% of component (d). More preferably, the curable composition does not contain component (d). The curable composition preferably further comprises a solvent as component (e). The solvent is preferably an inert solvent. The inert solvent does not react with any of the other components of the curable composition. In a preferred embodiment, component (e) comprises water and optionally an organic solvent, particularly if some or all of the organic solvent is water-miscible. Water is useful for dissolving components (a) and (b), and possibly component (c) as well, and the organic solvent is also useful for dissolving any organic components present in the curable composition.

[0036] Component (e) is useful for reducing the viscosity and / or surface tension of the curable composition. In a preferred embodiment, the curable composition contains 10 to 40 wt%, preferably 20 to 29 wt%, and particularly 20 to 26 wt% of component (e).

[0037] Examples of inert solvents that can be used as or in component (e) include water, alcohol-based solvents, ether-based solvents, amide-based solvents, ketone-based solvents, sulfoxide-based solvents, sulfone-based solvents, nitrile-based solvents, and organophosphorus-based solvents. Examples of alcohol-based solvents that can be used as or in component (e) (especially in combination with water) include methanol, ethanol, isopropanol, n-propanol, n-butanol, ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, and mixtures containing two or more of these. In addition, preferred inert organic solvents that can be used in component (e) include dimethyl sulfoxide, dimethylimidazolidinone, sulfolane, N-methylpyrrolidone, dimethylformamide, acetonitrile, acetone, 1,4-dioxane, 1,3-dioxolane, tetramethylurea, hexamethylphosphoramide, hexamethylphosphorotriamide, pyridine, propionitrile, butanone, cyclohexanone, tetrahydrofuran, tetrahydropyran, 2-methyltetrahydrofuran, ethylene glycol diacetate, cyclopentyl methyl ether, methyl ethyl ketone, ethyl acetate, γ-butyrolactone, and mixtures containing two or more of these.

[0038] The curable composition may further contain, preferably in small amounts, for example, 0-3 wt%, other components such as inhibitors and wetting agents to improve coating properties, biocides, and stabilizers.

[0039] The AEM preferably has low water permeability such that (hydrate) ions can pass through the membrane, but (free) water molecules do not easily pass through the membrane. The water permeability of the AEM is preferably 1.10 -11 m 3 / m 2 Lower than s·kPa, more preferably 5.10 -12 m 3 / m 2 Lower than s·kPa, especially 4.10 -12 m3 / m 2 Lower than s·kPa

[0040] The mole fraction of component (a) (all compounds in component (a)) relative to all curable compounds present in the curable composition is preferably at least 0.91, more preferably at least 0.95. A high ratio of component (a) relative to all curable compounds present in the curable composition is preferable for obtaining a film with high crosslinking density and therefore high permeability selectivity.

[0041] The permeability selectivity (PS) of the membrane of the present invention with respect to protons is preferably at least 50%, more preferably at least 60%, when determined as described later (in a 0.05 M to 4 M HCl system).

[0042] The electrical resistance (ER) of the film of the present invention is preferably 25 ohms / cm² when component (a) contains only one quaternary nitrogen atom. 2 Less than 20 ohms / cm², more preferably 20 ohms / cm² 2 It is less than . The ER of the film of the present invention is preferably 15 ohms / cm² when component (a) contains at least two quaternary nitrogen atoms. 2 It is less than [value]. ER can be determined (in 2M NaCl) as described later.

[0043] The mole fraction of component (a) relative to all curable compounds present in the curable composition is preferably a maximum of 1.0. The mole fraction of component (a) relative to all curable compounds present in the curable composition can be calculated by dividing the molar amount of component (a) by the total molar amount of all curable compounds present in the curable composition. Alternatively, the mole fraction can be determined by measuring what can be extracted from the anion exchange membrane, for example, as described on page 19 of WO2022 / 162083.

[0044] The distance between two nitrogen atoms in component (a) (compound of component (a)) is preferably at least 0.35 nm, which enhances the pH stability of the resulting film. Preferably, the distance between two nitrogen atoms in component (a) is less than 1.5 nm, which enhances the crosslinking density of the resulting film. Preferably, the nitrogen atoms have a cationic charge, which makes the anion exchange film suitable across the entire pH range. If the nitrogen atoms in component (a) do not have a cationic charge, the resulting anion exchange film can only be used in acidic environments.

[0045] Preferably, the ion exchange capacity (IEC) of the anion exchange membrane according to the present invention is at least 0.55 meq / g dry film, more preferably at least 0.65 meq / g dry film, when component (a) contains only one quaternary nitrogen atom. Preferably, the IEC of the anion exchange membrane according to the present invention is at least 1.15 meq / g dry film, more preferably at least 1.44 meq / g dry film, when component (a) contains at least two quaternary nitrogen atoms. Such an IEC can provide an anion exchange membrane with low electrical resistance. The IEC may be measured by the method described later.

[0046] Preferably, the IEC of the anion exchange membrane according to the present invention is less than 1.85 meq / g dry film when measured by the method described later. Such an IEC can provide an anion exchange membrane that maintains excellent permeation selectivity when in use because it does not swell excessively.

[0047] The anion exchange membrane of the present invention preferably further comprises a porous support. Examples of usable porous supports include woven and nonwoven synthetic fabrics, as well as extruded films. Examples include wet and dry nonwoven materials, spunbond and meltblown fabrics, and nanofiber webs made from polyethylene, polypropylene, polyacrylonitrile, polyvinyl chloride, polyphenylene sulfide, polyester, polyamide, polyaryletherketone, such as polyetheretherketone, and copolymers thereof. The porous support may also be a porous membrane, such as a membrane of polysulfone, polyethersulfone, polyphenylene sulfone, polyphenylene sulfide, polyimide, polyetherimide, polyamide, polyamideimide, polyacrylonitrile, polycarbonate, polyacrylate, cellulose acetate, polypropylene, poly(4-methyl-1-pentene), polyvinylidene fluoride, polytetrafluoroethylene, polyhexafluoropropylene, and polychlorotrifluoroethylene, and derivatives thereof.

[0048] The porous support preferably has an average thickness of 10 to 800 μm, more preferably 15 to 300 μm, particularly 20 to 150 μm, and even more particularly 30 to 130 μm, for example, about 60 μm or about 100 μm.

[0049] The porous support preferably has a porosity of 30-95%, more preferably 40-60%, in which case (in the final film) the pores are filled with an anion exchange polymer obtained by curing the composition, i.e., the film preferably comprises 40-60 vol% porous (unfilled) support material and 60-40 vol% anion exchange polymer material (i.e., a composition cured according to the first aspect of the present invention). These porosities provide an excellent balance of low electrical resistance and excellent permeability selectivity. The free volume of the porous support is determined by its thickness and weight (g / m²) before the film is made. 2 ) and fiber density (g / m 3 It can be calculated from the data of ).

[0050] If present, the porous support can be treated to modify its surface energy to a value greater than, for example, 45 mN / m, preferably greater than 55 mN / m. Suitable treatments include, for example, corona discharge treatment, plasma glow discharge treatment, flame treatment, ultraviolet light irradiation treatment, and chemical treatment, for the purpose of improving the wettability of the porous support and the adhesion of the porous support to the anion exchange film.

[0051] Commercially available porous supports are available from a variety of sources, including Freudenberg Filtration Technologies (Novatexx materials), Lydall Performance Materials, Celgard LLC, APorous Inc., SWM (Conwed Plastics, DelStar Technologies), Teijin Limited, Hirose Paper Co., Ltd., Mitsubishi Paper Mills Ltd., and Sefar AG.

[0052] Preferably, the porous support is a porous polymer support. Preferably, the porous support is a woven or nonwoven synthetic fabric, or an extruded film that does not have covalently bonded ionic groups.

[0053] Preferably, the anion exchange membrane of the present invention has an average thickness of 15 μm to 600 μm, more preferably 50 μm to 450 μm, and particularly 60 to 240 μm. A second aspect of the present invention is provided, which is a process for preparing an anion exchange film, comprising the step of curing a curable composition as defined with respect to the first aspect of the present invention (and preferably).

[0054] The process according to the second aspect of the present invention is preferably, i. A process of providing a porous support; ii. A step of impregnating a porous support with a curable composition; and iii. Process for curing the curable composition The curable composition includes the above-described elements.

[0055] The curable composition can be cured by any suitable process, examples of which include thermal curing, photocuring, electron beam (EB) irradiation, gamma ray irradiation, and combinations thereof.

[0056] Preferably, the process according to the second aspect of the present invention comprises a first curing step and a second curing step (double curing). Double curing is preferred because it increases the crosslinking density of the resulting anion exchange film, which in turn improves its permeation selectivity.

[0057] In a preferred embodiment of the process according to a second aspect of the present invention, the curable composition is first photocured, for example by irradiating the curable composition with ultraviolet (UV) or visible light, or by gamma or electron beam radiation, thereby polymerizing the curable components present in the curable composition, and then cured by applying a second curing step. The second curing step preferably includes thermal curing of the product of the first curing step, gamma ray irradiation, or EB irradiation, and therefore preferably the second curing step applies a different curing technique than the first curing step. If gamma or electron beam irradiation is used in the first curing step, a dose of preferably 60 to 200 kGy, more preferably 80 to 150 kGy, is applied to the curable composition.

[0058] In one embodiment, a process according to a second aspect of the present invention includes, in a first curing step, curing a curable composition to form an anion exchange film, winding the anion exchange film onto a core (optionally together with an inert polymer foil), and then performing a second curing step on the wound product of the first curing step.

[0059] In a preferred embodiment, the first and second curing steps are selected from (i) UV curing (first curing step), followed by thermal curing (second curing step); (ii) UV curing, followed by electron beam curing; and (iii) electron beam curing, followed by thermal curing, respectively.

[0060] Component (c) may contain one or more radical initiators, for example, a mixture of several photoinitiators (e.g., for single curing) or a mixture of a photoinitiator and a thermal initiator (e.g., for double curing).

[0061] In one embodiment, the second curing step is performed using gamma or electron beam (EB) irradiation. In the case of the second curing step by gamma or EB irradiation, a dose of 60 to 200 kGy is preferably applied to the product of the first curing step, and more preferably a dose of 80 to 150 kGy is applied.

[0062] Regarding the optional second curing step, thermocuring is preferred. Thermocuring is preferably carried out at a temperature of 50-100°C, more preferably 60-90°C. Thermocuring is preferably carried out for 2-72 hours, for example, about 3 hours for a sheet, and also 8-16 hours, for example, about 10 hours for a small roll, and 24-72 hours for a large roll. Optionally, after the first curing step, before winding it onto a spool, a polymer foil is applied to the product of the first curing step (this reduces oxygen inhibition, drying, and / or stacking of the product of the first curing step onto itself).

[0063] In a preferred process according to a second aspect of the present invention, the curable composition is continuously applied to a moving (preferably porous) support, preferably by a manufacturing unit comprising a curable composition application station, one or more irradiation sources for curing the curable composition, a film collection station, and means for moving the support from the curable composition application station to the irradiation sources and further to the film collection station.

[0064] The curable composition application station may be located upstream of the irradiation source, and the irradiation source may be located upstream of the film collection station. Suitable coating techniques for applying a curable composition to a support include slot die coating, slide coating, air knife coating, roller coating, screen printing, and dipping. Depending on the technique used and the desired final specifications, it is desirable to remove excess coating from the substrate, which can be done, for example, by roll-to-roll squeeze, roll-to-blade or blade-to-roll squeeze, blade-to-blade squeeze, or removal using a coating bar. Light curing is preferably performed for the first curing step, preferably at 40 to 20,000 mJ / cm². 2 This is done using a dose at a wavelength of 300 nm to 800 nm. In some cases, additional drying may be required, in which case a temperature of 40°C to 200°C may be employed. When gamma or EB curing is used, irradiation may be carried out under low-oxygen conditions, for example, with less than 200 ppm of oxygen.

[0065] A third aspect of the present invention provides a use (method of use) of an anion exchange membrane according to the first aspect of the present invention for use in an electromembrane process, for example, for processing polar liquids (e.g., desalting), producing acids and bases, or generating or storing electricity.

[0066] According to a fourth aspect of the present invention, an electrodialysis or reverse electrodialysis device, a bipolar electrodialysis device, an electrodeionization module, a flow-through capacitor, a diffusion dialysis apparatus, a membrane distillation module, an electrolytic cell, a redox flow battery, an acid-base flow battery, or a fuel cell is provided, comprising one or more anion exchange membranes according to a first aspect of the present invention. [Examples]

[0067] The present invention is illustrated here by the following non-limiting examples, all parts and percentages are by weight unless otherwise specified. pH stability The pH stability of anion exchange membranes was tested by immersing samples of the membrane under test in 4M HCl at 80°C for at least one month. After this treatment, the membrane's permeability selectivity (PS) was measured and compared to its PS before immersion. If the PS after immersion was at least 80% of the original PS, the membrane's pH stability was considered "OK"; if it was lower than 80% of the original PS, the pH stability was considered poor ("NG").

[0068] Permeability selectivity (PS) The permeability selectivity (PS) (%) (i.e., the selectivity of the anion exchange membrane for the passage of ions with the opposite charge) was measured as follows: The anion exchange membrane to be tested was placed in a system with two compartments. One compartment was filled with a 0.05 M HCl solution, and the other compartment was filled with a 4 M HCl solution, and the two compartments were separated by the membrane under test.

[0069] setting: The capillary and the Ag / AgCl reference electrode (Metrohm type 6.0750.100) contained 3M KCl; • Effective film area is 9.62 cm² 2 It was; The distance between the capillaries was approximately 15 mm. The measured temperature was 21.0 ± 0.2°C; • Two Cole Parmer Masterflex console drives (77521-47) with Easy Load II model 77200-62 gear pumps were used in two compartments; The flow rate was controlled to a constant 500 ml / min using a Porter Instruments flow meter (Type 150AV-B250-4RVS) and a Cole Palmer flow meter (Type G-30217-90). Before measurement, the anion exchange membrane sample was equilibrated in a 0.25 M HCl solution for 1 hour. After 20 minutes, the voltage was read from a standard VOM (multimeter).

[0070] PS was calculated from the voltage readings using the Nernst formula. Preferably, the PS for HCl was at least 50%.

[0071] Ion exchange capacity (IEC) Before measurement, the membrane was converted to chloride form by immersing the sample in a 2M NaCl solution for 1 hour. The 2M NaCl solution was changed once, and the sample was equilibrated for a further 24 hours. The membrane sample was then rinsed with Milli-Q® water, immersed in fresh Milli-Q® water for 1 hour, and rinsed again with Milli-Q® water.

[0072] A sample with a diameter of 2.0 cm was punched out from a membrane sample with chloride as a counterion (12.57 cm). 2 The samples were dried at 40°C for 24 hours and weighed. Next, the samples were placed in 75 ml of Milli-Q® water for 24 hours to remove all unpaired ions, followed by rinsing with Milli-Q® water, and each sample was immersed in 10.00 ml of 0.1 M AgNO3 solution, and the solution was shaken with the sample for 24 hours. During shaking, AgCl salt precipitated, causing Ag + - Ions - -As ions are removed, Cl - Aeon is No. 3 -The ions were completely exchanged. The samples were then removed from the AgNO3 solution and rinsed with a small amount of Milli-Q® water. The rinse water from each sample and the corresponding AgNO3 solution remaining after shaking the membrane sample were combined and titrated with a calibrated 0.1 M KBr solution. The results were compared to the titration value of 10.00 ml of a blank solution of 0.1 M AgNO3 without the membrane sample. Using equation (I), the difference in titration results between the blank solution and the test solution for each sample was correlated with the ion exchange capacity of the corresponding membrane: IEC(meq / g dry membrane)=(YX)×0.1 / W Equation (I) In the formula, Y is the amount (in ml) of 0.1 M KBr used in the titration of the blank AgNO3 solution; X is the amount (in ml) of 0.1 M KBr used in the titration of the AgNO3 solution in which the membrane sample was immersed, combined with Milli-Q® water used to rinse the membrane sample after immersion in the AgNO3 solution; W is the dry weight of the membrane (in grams).

[0073] Porosity of porous support The porosity of the porous support is determined by the thickness and weight (g / m²) provided by the supplier. 2 ) and fiber density (g / m 3 )Calculated from the data.

[0074] Electrical resistance (ER) The ER (ohms·cm) of the anion exchange membrane prepared in the examples 2 ) was measured using the method described by Dlugolecki et al., J. of Membrane Science 319 (2008), pp. 217-218, with the following modifications: The auxiliary membranes were CMX and AMX from Tokuyama Soda Co., Ltd. of Japan; The capillary and the Ag / AgCl reference electrode (Metrohm type 6.0750.100) contained 3M KCl; The calibration liquid and the liquids in sections 2, 3, 4, and 5 were 2.0 M NaCl solutions at 25°C; • Effective film area is 9.62 cm² 2 It was; The distance between the capillaries was 5.0 mm; The measured temperature was 25°C; • Cole Palmer Masterflex console drive (77521-47) with EasyLoad II Model 77200-62 gear pump was used in all sections; The flow rate of each stream was 475 ml / min and was controlled by a Porter Instruments flow meter (Type 150AV-B250-4RVS) and a Cole Palmer flow meter (Type G-30217-90); Prior to measurement, the anion exchange membrane samples were equilibrated in a 0.5 M NaCl solution at room temperature for at least 1 hour. ER is preferably low, for example, 15 ohms / cm². 2 It is less than.

[0075] Determination of the distance between nitrogen atoms in component (a) The distances between nitrogen atoms in each component (a) were determined by simulation using the open-source Avogadro software version 1.2.0 (Marcus D Hanwell, Donald E Curtis, David C Lonie, Tim Vandermeersch, Eva Zurek, and Geoffrey R Hutchison; see "Avogadro: An advanced semantic chemical editor, visualization, and analysis platform," Journal of Cheminformatics 2012, 4:17). The structure of each component (a) was plotted in the software, and the optimal chemical structure was determined using an automated optimization tool. The automated optimization tool was run with the following settings: - Force field: UFF - Steps per update: 4 - Algorithm: Molecular Dynamics (300K) - The atoms were neither fixed nor ignored.

[0076] Once the automated optimization tool finished (dE=0), the distance between nitrogen atoms was determined using the "click to measure" tool.

[0077] [Table 1]

[0078] Examples 1 to 6 and Comparative Examples 1 to 3.

[0079] [Table 2]

[0080] Procedure for preparing AXL3-1 to AXL3-5 The corresponding diamine (1 mmol) and TEMPO-OH (0.01 mmol) were dissolved in chloroform (100 ml). Potassium carbonate (4 mmol) was suspended in the mixture, and iodomethane (2.1 mmol) was added dropwise. The mixture was stirred at room temperature for 3 hours. Water was added to the reaction mixture, the organic layer was separated, and then washed with saturated ammonium chloride (2 × 150 ml). The organic layer was placed in a flask under reflux, and 2.05 mmol of CMS-14 was added dropwise. The mixture was gently warmed to 40°C and stirred overnight. After completion, the precipitated product was removed by filtration, and the solid was washed three times with diethyl ether. For AXL3-5, 2 mmol of potassium carbonate and 1.05 mmol of iodomethane were used instead of 4 mmol and 2.1 mmol, respectively. AXL3-1 to AXL3-5 were obtained as pale yellow solids.

[0081] CL-1 (used in Comparative Example 1) was synthesized as described in US2016 / 0177006.

[0082] [ka]

[0083] General procedure for preparing AXL-A and AXL-B for Comparative Examples 2 and 3

[0084] [ka]

[0085] To a 50% solution of the corresponding diamine (1 mmol) containing 4-OH-TEMPO (0.1 g) in ethyl acetate, CMS-14 (2.02 mmol) was added dropwise over 1 hour. The mixture was then vigorously stirred for 2 hours. The resulting precipitate was filtered, rinsed with additional ethyl acetate, and dried. The diammonium salt was isolated as a white solid. Table 2 below shows the structure and yield of the crosslinking agent prepared in this manner.

[0086] [Table 3]

[0087] [Table 4]

[0088] [Table 5]

[0089] In CL-1 and AXL-A, R a and R b One of each of the two is R c and R d Because each of the two is connected to one of the other, the distance between the two positively charged nitrogen atoms becomes even smaller, resulting in an unacceptable (poor) decrease in pH stability. This is undesirable.

[0090] AXL-B has an aromatic linking group L and exhibits low pH stability. CL-1, AXL-A, and AXL-B are crosslinking agents that do not have the claimed structure with respect to component (a).

[0091] Preparation of curable compositions and anion exchange films The curable compositions shown in Table 4 above were prepared by sequentially mixing the stated amounts of solid (in wt%) in a mixture of water and n-propanol at a temperature of 40°C. Each of the curable compositions listed in Table 4 was inoculated into a porous support (100 μm thick, 50% porosity, 50 g / m²) using a 100 μm Meyer bar. 2 Anion exchange films according to the first aspect and comparative examples of the present invention were prepared by applying the composition to a porous PP / PE support at room temperature (21°C), removing the excess using a 4 μm Meyer bar, and then curing the composition. Samples of the support containing the curable composition were placed at 5 m / min on a conveyor equipped with a D valve on a Light Hammer® 10 from Fusion UV Systems Inc., and UV curing was performed by exposing the samples to ultraviolet light emitted from the D valve at 50% power.

[0092] The UV-cured sample was placed in a metal-coated bag covered with 60 μm polyethylene terephthalate (PET) foil (from Toray Industries, Inc.) without any further processing. The bag was vacuum-sealed. The bag containing the film was placed in a standard oven and the film was heat-cured at 90°C for 3 hours.

Claims

1. An anion exchange film obtainable by curing a curable composition, wherein the curable composition comprises component (a) containing compound (A) and / or compound (B) and / or compound (C), During the ceremony, (A) is a non-aromatic bicyclic structure containing two nitrogen atoms, which may be optionally substituted. The rings of the non-aromatic bicyclic structure are independently 4, 5, 6, or 7 members; Each of the rings contains a nitrogen atom, which may be located at the bridgehead; Each of the aforementioned nitrogen atoms contains hydrogen, C １～３ Alkyl, C ５～６ The compound is bonded with one or two groups independently selected from cycloalkyl and vinylbenzyl groups, wherein the compound comprises at least two vinylbenzyl groups; (B) is a C containing one nitrogen atom, which may be optionally substituted, and a nitrogen atom as a substituent on the ring. １～６ A 5, 6, or 7-membered non-aromatic heterocycle containing an alkyl group; The nitrogen atom of the aforementioned non-aromatic heterocycle is replaced with hydrogen, C １～３ Alkyl, C ５～６ The compound is bonded with one or two groups independently selected from cycloalkyl and vinylbenzyl groups, wherein the compound comprises at least two vinylbenzyl groups; (C) is an optionally substituted non-aromatic spiro ring structure containing two nitrogen atoms, The rings of the aforementioned non-aromatic spiro ring structure are independently 4, 5, or 6 members; Each of the rings contains at least one nitrogen atom, which may be located at the bridgehead; Each of the aforementioned nitrogen atoms contains hydrogen, C １～３ Alkyl, C ５～６ The anion exchange membrane is bonded to one or two groups independently selected from cycloalkyl and vinylbenzyl groups, wherein the compound contains at least two vinylbenzyl groups.

2. The anion exchange membrane according to claim 1, wherein component (a) contains at least one quaternary nitrogen atom.

3. The anion exchange membrane according to claim 1, wherein component (a) contains at least two quaternary nitrogen atoms.

4. The anion exchange film according to claim 1, wherein the distance between two nitrogen atoms in component (a) is at least 0.35 nm.

5. Any optional substituent is C １～３ The anion exchange membrane according to claim 1 or 4, wherein the anion exchange membrane is alkyl.

6. The anion exchange membrane according to claim 1 or 4, wherein component (a) comprises two, three, or four vinylbenzyl groups.

7. An anion exchange membrane according to claim 1 or 4, wherein the dry film is at least 0.55 meq / g and has a lower ion exchange capacity than a dry film of 1.85 meq / g.

8. The anion exchange membrane according to claim 1 or 4, wherein component (a) has a molecular weight of less than 700 daltons.

9. The anion exchange membrane according to claim 1 or 4, wherein the curable composition comprises 65 to 85 wt% of component (a), 0 to 10 wt% of component (b) a monomer containing a cationic group and one or only one curable ethylenically unsaturated group, 0 to 10 wt% of component (c) a radical initiator, 0 to 5 wt% of component (d) a monomer not containing a cationic group, and 10 to 40 wt% of component (e) a solvent.

10. An anion exchange membrane according to claim 1 or 4, comprising at least 1 ppm of component (a).

11. (i) A step of providing a curable composition as defined in claim 1 or 4; (ii) a step of applying the curable composition onto a porous support to impregnate the porous support with at least a portion of the curable composition; and (iii) A step of curing the curable composition. A process for preparing anion exchange membranes, including [specific components / methods].

12. An electrodialysis device, a bipolar electrodialysis device, an electrolytic cell, a redox flow battery, an acid-base flow battery, or a fuel cell comprising one or more anion exchange membranes as described in claim 1 or 4.

13. Use of an anion exchange membrane according to claim 1 or 4 for processing polar liquids, for the production of acids and bases, or for the generation or storage of electricity.

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