membrane

Abstract

Monomer a of Formula I: AR 1 -(CH2) n -N + (R a R b )-(CH2) n -AR 2 , X - wherein each n is independently 1 or 2; (1) R a and R b are each independently optionally substituted C 1~3 alkyl group or optionally substituted C 2~3 (2) R is an alkenyl group; a and R b form an optionally substituted five- or six-membered ring together with the positively charged nitrogen atom to which they are attached; (3) R a and R b One of them is an arbitrarily replaceable C 1~3 alkyl group or optionally substituted C 2~3 R is an alkenyl group a and R b The other is AR 1 -(CH2) n -N + together with the R group to form an optionally substituted 5- or 6-membered ring; or (4) R a is AR 1 -(CH2) n -N + R 1 and R 2 form an optionally substituted 5- or 6-membered ring together. b is N + -(CH2) n -AR 2 together with the group X to form an optionally substituted 5- or 6-membered ring; - is the anion; AR 1 and AR 2 each independently contains an aromatic group; (1') AR 1 and AR 2 (2') monomer a of formula I contains at least two curable ethylenically unsaturated groups; and (3') the molar fraction of component a relative to all curable components of the curable composition is at least 0.90.

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 WDR to form acids, and the salt cations combine with OH- to form bases. For example, if NaCl is used in the feed stream, the monopolar membrane will... - From Na + By separating them, NaOH and HCl are formed.

[0006] To generate high concentrations of acids and bases, it is important that the monopolar membrane has very high pH stability and high durability (high pH stability and durability extend the membrane's lifespan). High efficiency in the acid and base generation process is also desirable. This is achieved by the membrane having very high permeation selectivity, which allows H + and OH - It is necessary to prevent ions from reaching the wrong channel, recombining, and leading to product loss. In particular, for anion exchange membranes, achieving high proton blocking performance at high concentrations is difficult due to the small size of protons. [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] The object of the present invention is to provide an anion exchange membrane that is mechanically strong, has high stability at very low pH values, and exhibits high permeation selectivity at high acid concentrations. [Modes for carrying out the invention]

[0008] According to a first aspect of the present invention, an anion exchange membrane obtainable by curing a curable composition, the curable composition comprising: (a) a monomer (a) of formula (I) AR 1 -(CH2) n -N + (R a R b )-(CH2) n -AR 2 、X - Formula (I) and wherein each n independently has a value of 1 or 2; (i) R a and R b are each independently an optionally substituted C 1~3 alkyl group or an optionally substituted C 2~3 alkenyl group; or (ii) R a and R b together with the positively charged nitrogen atom to which they are attached form an optionally substituted 5- or 6-membered ring; or (iii) one of R a and R b is an optionally substituted C 1~3 alkyl group or an optionally substituted C 2~3 alkenyl group, and the other of R a and R b forms an optionally substituted 5- or 6-membered ring together with the group of formula AR 1 -(CH2) n -N + ; or (iv) R a forms an optionally substituted 5- or 6-membered ring together with the group of formula AR 1 -(CH2) n -N + , and R b forms an optionally substituted 5- or 6-membered ring together with the group of formula N + -(CH2) n -AR 2 ; X - is an anion; AR 1 and AR 2 Each of these independently contains an aromatic group; (I)AR 1 and AR 2 At least one of them comprises a curable ethylenically unsaturated group; (II) Monomer (a) of formula (I) contains at least two curable ethylenically unsaturated groups; (III) The anion exchange film is provided wherein the mole fraction of component (a) relative to all curable components of the curable composition is at least 0.90.

[0009] 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, even if they are not specifically mentioned. In addition, when an element is referred to by the indefinite article “a” or “an,” the possibility of more than one element being present is not excluded unless the context clearly requires that only one or a single element be present. Thus, the indefinite article “a” or “an” usually means “at least one.”

[0010] Preferably, monomer (a) contains at least two curable ethylenically unsaturated groups, and more preferably two and only two curable ethylenically unsaturated groups. Preferably, the curable ethylenically unsaturated groups are AR 1 and / or AR 2 It is present in monomer (a) present inside. In a preferred embodiment, AR 1 and AR 2 Each contains one or only one curable ethylenically unsaturated group, and monomer (a) has a total of two curable ethylenically unsaturated groups.

[0011] A curable ethylenically unsaturated group can react with other curable ethylenically unsaturated groups to form covalent bonds, for example, when heated and / or irradiated with light (e.g., ultraviolet light) or an electron beam.

[0012] The preferred curable ethylenically unsaturated groups are vinyl groups and allyl groups, with vinyl groups being the most preferred. The vinyl group (CH2=CH-) is non-acrylic, meaning it is not bonded to a (C=O)O- or (C=O)NH- group.

[0013] A nitrogen atom with a positive charge as shown in formula (I) (N + ) is a non-aromatic system, meaning it is not part of an aromatic heterocycle. Preferably, anion X - It does not react with other components of the curable composition, i.e., X - X is inactive. - Preferred anions represented by include hydroxide ions, fluoride ions, chloride ions, bromide ions, iodide ions, nitrate ions, thiocyanate ions, hexafluoroborate ions, methanesulfonate ions, trifluoromethanesulfonate ions, formate ions, and acetate ions. Most preferably, X - This is a chloride anion because it can provide a monomer of formula (I) with excellent solubility without dramatically increasing the molecular weight of monomer (a) of formula (I).

[0014] Preferably, each n independently has a value of 1. In a particularly preferred embodiment, both n have a value of 1. In one embodiment, R a and R b Each of these can be substituted independently of the others. 1~3 Alkyl groups (e.g., methyl, ethyl, propyl, or isopropyl) and optionally substituted C 2~3 It is selected from alkenyl groups (e.g., -CH=CH2 or -CH2CH=CH2).

[0015] In another embodiment, R a and R b Together with the positively charged nitrogen atom to which they are bonded, they form optionally substituted five or six-membered rings, such as optionally substituted pyrrolidinium, pyrrolinium, imidazolinium, piperidinium, or morpholinium rings.

[0016] In another embodiment, R a and R b One of them may be arbitrarily substituted C 1~3 C is an alkyl group or optionally substituted. 2~3 It is an alkenyl group, R a and R b The other side is, formula AR 1 -(CH2) n -N + The basis of (in the formula, AR 1 Together with (where n is as defined above), they form an optionally substituted 5 or 6-membered ring, for example, an optionally substituted pyrrolidinium, pyrrolidinium, piperidinium, or morpholinium ring, in which case they have a fused aromatic ring (e.g., a benzene ring) thereon (preferably two or more, preferably one, curable ethylenically unsaturated group bonded to the benzene ring).

[0017] In another embodiment, R a is, formula AR 1 -(CH2) n -N + The basis of (in the formula, AR 1 (and n is as defined above) together form a 5 or 6-membered ring which may be optionally substituted, R b is, formula N + -(CH2) n -AR 2 The basis of (in the formula, AR 2 Together with n (as defined above), they form a 5- or 6-membered ring, which may be optionally substituted.

[0018] The preferred, optionally substituted, five- or six-membered rings are as defined above (one example being the 6-azoniaspiro[5.5]undecylene ring). A preferred optional substituent is a curable ethylenically unsaturated group (as described above, and therefore preferred).

[0019] Preferably, AR 1 and AR 2 Each independently contains a phenyl or styrenel group. More preferably, AR 1 and AR 2 Both are styrene groups. In a preferred embodiment, monomer (a) is given by formula (II):

[0020] [ka]

[0021] It has, in the formula, R a , R b and X - This is defined as above. Component (a) may optionally contain one or more monomers (a) of formula (I) (more preferably formula (II)), for example, AR 1 and / or AR 2 The compound may contain a mixture of isomers in which the curable unsaturated group present is located at different positions (e.g., ortho, meta, and / or para).

[0022] Examples of monomers that can be used as monomer (a) include the compounds AXL-1 to AX-11 shown below.

[0023] [ka]

[0024] [ka]

[0025]

Chem.

[0026] The curable composition preferably contains 50 to 90 wt% of component (a), more preferably 65 to 85 wt%, particularly 69 to 83 wt% of component (a). In one embodiment, the anion exchange membrane according to the 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, particularly at least 100 ppm of monomer (a). Preferably, the anion exchange membrane contains less than 20,000 ppm of monomer (a), more preferably less than 10,000 ppm of monomer (a).

[0027] The curable composition optionally further contains, as component (b), a monomer containing a cationic charge and only one curable ethylenically unsaturated group. Preferably, the curable composition does not contain component (b), or the 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).

[0028] In monomer (b), the group having a cationic charge is preferably a quaternary ammonium group. The one and only curable ethylenically unsaturated group present in monomer (b) is preferably a vinyl or allyl group, more preferably a vinyl group.

[0029] Component (b) may contain one or more monomers (b) containing a cationic charge and only one curable ethylenically unsaturated group. In one embodiment, component (b) has the formula (SM), wherein R 1 , R 2 and R 3 each independently represents an alkyl group or an aryl group, or R 1 , R 2and 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 - represents an anion, preferably a chloride ion, bromide ion, iodide ion, or hydroxide ion.

[0030] [ka]

[0031] Examples of component (b) in formula (SM) include the following compounds:

[0032] [ka]

[0033] The above ingredients can be prepared, for example, as described in US2016177006. The curable composition optionally further comprises a radical initiator as component (c). Preferred radical initiators include thermal initiators, photoinitiators, and combinations thereof.

[0034] 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.

[0035] 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].

[0036] 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.

[0037] 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.

[0038] 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).

[0039] 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.

[0040] Component (e) is useful for reducing the viscosity and / or surface tension of the curable composition. In a preferred embodiment, the curable composition comprises 10 to 40 wt%, particularly 20 to 30 wt%, of component (e).

[0041] 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.

[0042] The mole fraction of component (a) relative to all curable compounds present in the curable composition is preferably at least 0.91, and 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. The mole fraction of component (a) relative to all curable compounds present in the curable composition is preferably up to 1.0.

[0043] 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] Preferably, the ion exchange capacity (IEC) of the anion exchange membrane according to the present invention is at least 1.1 meq / g dry film, more preferably at least 1.2 meq / g dry film, when measured by the method described later. Such an IEC can provide an anion exchange membrane having low electrical resistance.

[0045] Preferably, the IEC of the anion exchange membrane according to the present invention is less than 1.65 meq / g dry film when measured by the method described later. Such an IEC can provide an anion exchange membrane that retains excellent permeation selectivity when in use because it does not swell excessively.

[0046] The anion exchange membrane of the present invention preferably further comprises a porous support. Examples of porous supports that can be used 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 porous membranes, such as membranes 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.

[0047] The porous support preferably has an average thickness of 10 to 800 μm, more preferably 15 to 300 μm, particularly 20 to 150 μm, even more particularly 30 to 130 μm, for example, about 60 μm, or about 100 μm.

[0048] The porous support preferably has a porosity of 30-95%, more preferably 60-75%, 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 25-40 vol% porous (unfilled) support material and 75-60 vol% anion exchange polymer material (i.e., a composition cured according to the first aspect of the present invention). The porosity of the support can be determined before film formation by a porometer, for example, Porolux® 1000 from IB-FT GmbH, Germany.

[0049] 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.

[0050] 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.

[0051] 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.

[0052] 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).

[0053] 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 is as defined above, and includes the following.

[0054] 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.

[0055] 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 and subsequently improves its permeation selectivity.

[0056] 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. When 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.

[0057] 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.

[0058] 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.

[0059] 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).

[0060] 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, preferably a dose of 60 to 200 kGy is applied to the product of the first curing step, and more preferably a dose of 80 to 150 kGy is applied.

[0061] Regarding an 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. After the first curing step, before winding it onto a spool, a polymer foil is optionally applied to the product of the first curing step (this reduces oxygen inhibition, drying, and / or adhesion of the product of the first curing step to itself).

[0062] 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.

[0063] 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 40-20000 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.

[0064] 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.

[0065] 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]

[0066] The present invention is illustrated here by the following non-limiting examples, all parts and percentages are by weight unless otherwise specified.

[0067] pH stability The pH stability of anion exchange membranes was tested by immersing a sample 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. The membrane's pH stability was considered "OK" if the PS after immersion was at least 80% of the original PS; 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) equipped with an Easy Load II model 77200 - 62 gear pump were used in two compartments; · A Porter Instrument flow meter (type 150AV - B250 - 4RVS) and a Cole Parmer flow meter (type G - 30217 - 90) were used to control the flow rate constantly at 500 ml / min; · Before measurement, the anion exchange membrane samples were equilibrated in 0.25 M HCl solution for 1 hour. After 20 minutes, the voltage was read from a standard VOM (multimeter).

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

[0071] Ion exchange capacity (IEC) Before measurement, the membranes were made into chloride form by immersing the samples in 2 M NaCl solution for 1 hour. The 2 M NaCl solution was exchanged once, and the samples were further equilibrated for 24 hours. Then, the membrane samples were rinsed with Milli - Q (registered trademark) water, immersed in fresh Milli - Q (registered trademark) water for 1 hour, and rinsed with Milli - Q (registered trademark) water again.

[0072] Samples with chloride as the counter ion were punched out into samples with a diameter of 2.0 cm (12.57 cm 2 ), dried at 40 °C for 24 hours, and weighed. Then the samples were placed in 75 ml of Milli - Q (registered trademark) water for 24 hours to remove all non - counter ions, followed by rinsing with Milli - Q (registered trademark) 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, as Ag + ions were removed by the precipitation of AgCl salt with Cl - ions, as Cl - ions were removed, NO3 -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 film)=(YX)×0.1 / W Equation (I) In the formula, Y is the volume (in ml) of 0.1 M KBr used in the titration of the blank AgNO3 solution; X is the volume (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; and W is the dry weight (in grams) of the membrane.

[0073] 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.

[0074] ER is preferably low, for example, 15 ohms / cm². 2 It is less than.

[0075] [Table 1]

[0076] CL-1 was synthesized as described in US20160177006, Example 1:

[0077] [ka]

[0078] General procedure for preparing AXL-1~4

[0079] [ka]

[0080] To a 40% solution (1 mmol) of the corresponding amine containing 4-OH-TEMPO (0.1 g) in PW, CMS-14 (2.02 mmol) was added dropwise over 1 hour. The mixture was then vigorously stirred for 2 hours. Diethyl ether was added, and the aqueous phase was extracted three times (3 × 200 mL). The product was isolated from water as a pale yellow solid by spray drying.

[0081] [Table 2]

[0082] Examples 1 to 6 and Comparative Examples 1 and 2.

[0083] [Table 3]

[0084] [Table 4]

[0085] In Comparative Example 1, the mole fraction of component (a) is low, resulting in a low PS. In Comparative Example 2, component (a) does not follow formula (I).

[0086] Preparation of curable compositions and anion exchange films The curable compositions shown in Table 3 above were prepared by sequentially mixing the stated amounts of components (in wt%) in the stated amounts of water / n-propanol mixture at a temperature of 40°C.

[0087] Anion exchange films according to the first aspect and comparative examples of the present invention were prepared by applying each of the curable compositions listed in Table 3 to a porous support (PS1) at room temperature (21°C) using a 100 μm Meyer bar, removing excess curable composition using a 4 μm Meyer bar, and then curing the composition. Samples of the porous support containing the curable composition were placed at 5 m / min on a conveyor equipped with a D valve in a Light Hammer® 10 from Fusion UV Systems Inc., and UV curing was performed by exposing the curable composition to ultraviolet light emitted from the D valve at 50% power. The UV-cured samples were covered with 60 μm polyethylene terephthalate (PET) foil (from Toray Industries, Inc.) with no surface treatment and placed in a metal-coated, vacuum-sealed bag. The bag containing the UV-cured film was then heat-cured in a standard oven at 90°C for 3 hours (as a second curing step).

Claims

1. An anion exchange film obtainable by curing a curable composition, wherein the curable composition is (a) Monomer (a) of equation (I) AR １ -(CH ２ ) ｎ -N ＋ (R ａ R ｂ )-(CH ２ ) ｎ -AR ２ 、X － including formula (I), During the ceremony, Each n independently has a value of either 1 or 2; (i) R ａ and R ｂ Each of these can be substituted independently and arbitrarily. １～３ C is an alkyl group or optionally substituted. ２～３ It is an alkenyl group; or (ii) R ａ and R ｂ They form a optionally substituted five- or six-membered ring with the positively charged nitrogen atom to which they are bonded; or (iii) R ａ and R ｂ One of them may be arbitrarily substituted C １～３ C is an alkyl group or optionally substituted. ２～３ It is an alkenyl group, R ａ and R ｂ The other is formula AR １ - (CH ２ ) ｎ -N ＋ Together with the base, it forms a 5 or 6-membered ring which may be optionally substituted; or (iv)R ａ is formula AR １ - (CH ２ ) ｎ -N ＋ Together with the base, it forms a 5 or 6-membered ring which may be optionally substituted, R ｂ is, formula N ＋ - (CH ２ ) ｎ -AR ２ Together with the base, it forms a 5 or 6-membered ring which may be optionally substituted; X － is an anion; AR １ and AR ２ Each of them independently contains an aromatic group; (I) AR １ and AR ２ At least one of them comprises a curable ethylenically unsaturated group; (II) Monomer (a) of formula (I) comprises at least two curable ethylenically unsaturated groups; (III) The anion exchange membrane, wherein the mole fraction of component (a) relative to all curable components of the curable composition is at least 0.

90.

2. The anion exchange membrane according to claim 1, wherein n in formula (I) has a value of 1.

3. AR of equation (I) １ and AR ２ The anion exchange membrane according to claim 1 or 2, wherein both contain a styrenel group.

4. The anion exchange membrane according to claim 1 or 2, wherein the curable composition further comprises a monomer (b) having a cationic charge and a single curable ethylenically unsaturated group.

5. The anion exchange membrane according to claim 1 or 2, wherein the curable ethylenically unsaturated group is a vinyl group.

6. An anion exchange membrane according to claim 1 or 2, having a lower ion exchange capacity than a 1.65 meq / g dry membrane.

7. The anion exchange membrane according to claim 1 or 2, wherein the curable composition comprises 50 to 90 wt% of component (a), 0 to 10 wt% of component (b) a monomer containing a cationic group and 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.

8. The anion exchange membrane according to claim 1 or 2, further comprising a porous support.

9. A process for preparing an anion exchange film, comprising the step of curing a curable composition according to claim 1 or 2.

10. (i) A step of providing the curable composition according to claim 1; (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. The process according to claim 9, including the process described in claim 9.

11. An electrodialysis device, a bipolar electrodialysis device, an electrolytic cell, a redox flow battery, an acid-base flow battery, or a fuel cell comprising the anion exchange membrane according to claim 1 or 2.

12. Use of an anion exchange membrane according to claim 1 or 2 for processing polar liquids, for producing acids and bases, or for generating or storing electricity.

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