Anion exchange membrane and manufacturing method therefor

Abstract

Disclosed is an anion exchange membrane comprising: a first polymer having a repeating unit represented by chemical formula 1; and a second polymer, which is a polymer or copolymer of a composition comprising a monomer represented by chemical formula 2, wherein the second polymer is entangled in a network formed by the first polymer, so as to form a semi-interpenetrating polymer network (semi-IPN) structure. <Chemical formula 1> <Chemical formula 2> The description of chemical formulas 1 and 2 refers to the present specification.

Description

Anion exchange membrane and method for manufacturing the same

[0001] The present disclosure relates to an anion exchange membrane and a method for manufacturing the same.

[0002] An ion exchange membrane is a synthetic resin membrane that selectively allows cations and anions to pass through. Cation exchange membranes have negatively charged functional groups, allowing them to selectively allow cations to pass through, while anion exchange membranes have positively charged functional groups, allowing them to selectively allow anions to pass through. Ion exchange membranes are widely used in various fields, including seawater concentration and desalination, organic acid purification, and precious metal recovery, based on electrodialysis technology. They are also being applied to hydrogen production technology through water electrolysis, which has recently been attracting attention as a sustainable energy source and as a way to reduce CO2 emissions due to global warming. Water electrolysis technologies using ion exchange membranes include cation exchange membrane or proton exchange membrane electrolysis technology that utilizes proton transfer, and anion exchange membrane electrolysis technology that utilizes anion exchange membranes in alkaline solution environments. Anion exchange membrane electrolysis technology utilizes water electrolysis through the conduction of hydroxide ions. Compared to proton exchange membrane electrolysis technology that utilizes hydrogen ion conduction, it has the advantage of allowing the use of low-cost water splitting catalysts, and thus, much research has been conducted recently.

[0003] These anion exchange membranes can be applied to water treatment systems such as electrodialysis, bipolar membrane electrodialysis, capacitive desalination, and electrodeionization, or to systems such as fuel cells, water electrolysis, reverse electrodialysis, and redox flow batteries. Perfluorinated anion exchange membranes can be used as anion exchange membranes, but hydrocarbon anion exchange membranes are used in actual systems due to their high price. However, hydrocarbon anion exchange membranes have limitations in increasing membrane properties such as ion exchange capacity (IEC) because a certain portion of porous support exists within the membrane.

[0004] The present invention provides an anion exchange membrane formed as a self-supporting membrane without a porous polymer support, which increases the mobility of hydroxide ions, has a high current density, and has low hydrogen permeability, and a method for manufacturing the same.

[0005] According to one aspect,

[0006] A first polymer having a repeating unit represented by the following chemical formula 1; and

[0007] A second polymer, which is a polymer or copolymer of a composition including a monomer represented by the following chemical formula 2;

[0008] An anion exchange membrane is provided in which the second polymer is entangled with the network formed by the first polymer to form a semi-interpenetrating polymer network (semi-IPN) structure:

[0009] <Chemical Formula 1>

[0010]

[0011] <Chemical Formula 2>

[0012]

[0013] Among the above chemical formulas 1 and 2,

[0014] R1 to R3 and R 11 Inland R 14 are independently substituted or unsubstituted C1-C 20 Alkyl group, substituted or unsubstituted C2-C 20 Alkenyl group and -(CH2) n -Selected from N(Q1)(Q2),

[0015] Each of Q1 and Q2 is hydrogen or a substituted or unsubstituted C1-C3 alkyl group,

[0016] R 11 and R 12 , R 11 and R 13 , R 11 and R 14 , R 12 Wow R13 , R 12 Wow R 14 and R 13 and R 14 Each of them optionally combines with the other,

[0017] L1 is a single bond and substituted or unsubstituted C1-C 20 Selected from alkylene groups,

[0018] a1 is 0 or 1, and if a1 is 0 (L1) a1 does not exist and i) R 11 and R 12 and ii) R 13 and R 14 At least one of them is combined with each other,

[0019] Vi is vinyl,

[0020] X - , Y - and Z - are independent of each other, F - , Cl - , Br - and I - Selected from among,

[0021] p is selected from 60 to 80,

[0022] q is selected from 20 to 40,

[0023] The sum of p and q is 100,

[0024] Each of n, n1 and n2 is selected from integers greater than or equal to 1.

[0025] According to another aspect,

[0026] A step of mixing the first polymer and the monomer into a solvent;

[0027] A step of casting the mixture onto a substrate;

[0028] A step of forming a film by irradiating the cast mixture with ultraviolet rays; and

[0029] A method for manufacturing an anion exchange membrane is provided, including a step of peeling the substrate from the film.

[0030] An anion exchange membrane formed as a self-supporting membrane without a porous polymer support and simultaneously containing both the first polymer and the second polymer described above can have a high ion exchange capacity (IEC) while having a low sheet resistance and a high ion conductivity level. In addition, as the second polymer is formed, it is entangled with the network formed by the first polymer to form a semi-interpenetrating polymer network (semi-IPN) structure, and an anion exchange membrane having such a dense structure can have a low hydrogen permeability.

[0031] Hereinafter, an ion exchange membrane and its manufacturing method according to an embodiment will be described in more detail. The following is provided as an example and is not intended to limit the present invention, which is defined solely by the scope of the claims set forth below.

[0032] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. In case of conflict, the present specification, including its definitions, shall prevail.

[0033] Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, suitable methods and materials are described herein.

[0034] The expressions “at least one,” “one or more,” or “one or more” preceding components in this specification may supplement the entire list of components and do not mean that they supplement individual components described above.

[0035] The term "include" in this specification is used to indicate that other components may be added and / or interposed, rather than to the exclusion of other components, unless specifically stated otherwise.

[0036] Unless otherwise specified herein, the unit “parts by weight” means the weight ratio between each component.

[0037] The numerical values ​​set forth in this specification may be understood to include the meaning of "about" even if not explicitly stated.

[0038] In this specification, the term “semi-interpenetrating polymer network (semi-IPN) structure” means a structure in which only one of two polymer components is selectively crosslinked without affecting the other component.

[0039] In this specification, "carbon number a to b" or "C a -C b "a and b of the above represent the number of carbon atoms in a specific functional group. That is, the functional group may include carbon atoms from a to b. For example, "an alkyl group having 1 to 2 carbon atoms" or "a C1-C2 alkyl group" means an alkyl group having 1 to 2 carbon atoms, i.e., -CH3 and -CH2CH3.

[0040] As used herein, the term "alkyl" means a branched (branched) or unbranched (straight-chain) aliphatic hydrocarbon. Alkyl groups include, but are not necessarily limited to, methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, s-butyl, tert-butyl, pentyl, hexyl, cyclopropyl, cyclopentyl, cyclohexyl, cycloheptyl, and the like, each of which may be optionally substituted or unsubstituted.

[0041] As used herein, the term "alkylene" refers to a divalent group having the same structure as "alkyl." Alkylene groups include, but are not necessarily limited to, methylene, ethylene, propylene, butylene, pentylene, hexylene, and heptylene groups, each of which may be optionally substituted or unsubstituted.

[0042] As used herein, the term "alkenyl" refers to a monovalent hydrocarbon group containing one or more carbon-to-carbon double bonds in the middle or terminal of an alkyl group. Alkenyl groups include, but are not necessarily limited to, ethenyl, propenyl, and butenyl groups, each of which may be optionally substituted or unsubstituted.

[0043] In this specification, a substituent is derived by exchanging one or more hydrogens in an unsubstituted mother group with another atom or functional group. For example, when a functional group is considered to be "substituted," it means that the functional group is C1-C 40 Alkyl group, C1-C 40 Alkoxy group, C2-C 40 Alkenyl group, C2-C 40 alkynyl group, C3-C 40 Cycloalkyl group, C3-C 40 Cycloalkenyl group, C6-C 40 It means that it is substituted with one or more substituents selected from among aryl groups, etc. When it is described that a functional group is "optionally substituted", it means that the functional group can be substituted with the above-mentioned substituents.

[0044] Conventional anion exchange membranes include a porous polymer support that acts as a reinforcing material to improve ionic conductivity and durability, and an electrolyte with anion exchange capacity is filled into the porous polymer support. However, these anion exchange membranes have relatively complex manufacturing processes, high sheet resistance, low hydroxide ion conductivity, and problems such as reduced durability and membrane properties due to gaps between the crosslinking electrolyte and the reinforcing material during long-term operation.

[0045] The present inventors have solved the above-described problems by providing an anion exchange membrane in the form of a free-standing film without a porous polymer support. Therefore, the anion exchange membrane according to one aspect is distinctly different from an anion exchange membrane in which an electrolyte with anion exchange capacity is filled on the surface or within the pores of a porous polymer support.

[0046] According to one aspect,

[0047] A first polymer having a repeating unit represented by the following chemical formula 1; and

[0048] A second polymer, which is a polymer or copolymer of a composition including a monomer represented by the following chemical formula 2;

[0049] An anion exchange membrane is provided in which the second polymer is entangled with the network formed by the first polymer to form a semi-interpenetrating polymer network structure:

[0050] <Chemical Formula 1>

[0051]

[0052] <Chemical Formula 2>

[0053]

[0054] Among the above chemical formulas 1 and 2,

[0055] R1 to R3 and R 11 Inland R 14 are independently substituted or unsubstituted C1-C 20 Alkyl group, substituted or unsubstituted C2-C 20 Alkenyl group and -(CH2) n -Selected from N(Q1)(Q2),

[0056] Each of Q1 and Q2 is hydrogen or a substituted or unsubstituted C1-C3 alkyl group,

[0057] R 11 and R 12 , R 11 and R13 , R 11 and R 14 , R 12 Wow R 13 , R 12 Wow R 14 and R 13 and R 14 Each of them optionally combines with the other,

[0058] L1 is a single bond and substituted or unsubstituted C1-C 20 Selected from alkylene groups,

[0059] a1 is 0 or 1, and if a1 is 0 (L1) a1 does not exist and i) R 11 and R 12 and ii) R 13 and R 14 At least one of them is combined with each other,

[0060] Vi is vinyl,

[0061] X - , Y - and Z - are independent of each other, F - , Cl - , Br - and I - Selected from among,

[0062] p is selected from 60 to 80,

[0063] q is selected from 20 to 40,

[0064] The sum of p and q is 100,

[0065] Each of n, n1 and n2 is selected from integers greater than or equal to 1.

[0066] First polymer

[0067] The first polymer may have a repeating unit represented by the above chemical formula 1 and may include a quaternary ammonium salt. The first polymer may serve as a main chain of an anion exchange membrane. The first polymer may form a three-dimensional network. The first polymer may not be chemically bonded to the second polymer. The weight of the first polymer in the anion exchange membrane may be greater than the weight of the second polymer.

[0068] According to one embodiment, at least one of R1 to R3 in chemical formula 1 is substituted or unsubstituted C1-C 20 It may be an alkyl group. For example, each of R1 to R3 is a substituted or unsubstituted C1-C 20 It may be an alkyl group. Specifically, each of R1 to R3 may be selected from a methyl group, an ethyl group, and a propyl group.

[0069] In the above chemical formula 1, q may be selected from 20 to 40, for example, q may be selected from 25 to 35. When q is less than 20, the physical properties of the anion exchange membrane, such as surface resistance, ion conductivity, ion exchange capacity, current density, and hydrogen permeability, may be reduced, and when q is greater than 40, the mechanical strength may be reduced, and there may be a problem of reduced solubility when manufacturing the solution.

[0070] Second polymer

[0071] The second polymer may be a cross-linked product of a composition including a monomer represented by the above chemical formula 2. During the manufacture of the anion exchange membrane, the monomer may be distributed between the three-dimensional networks formed by the first polymer. The monomer may include a vinyl group. When irradiated with ultraviolet rays, a bond between the monomers may be formed by the vinyl group. The second polymer formed by polymerization of the monomer may be entangled with the three-dimensional network formed by the first polymer. Therefore, the anion exchange membrane may have a semi-interpenetrating polymer network structure in which the first polymer and the second polymer are entangled with each other. That is, the first polymer and the second polymer may be physically entangled rather than chemically bonded. The weight of the second polymer in the anion exchange membrane may be greater than the weight of the first polymer.

[0072] According to one embodiment, the monomer may be represented by any one of the following chemical formulas 2-1 to 2-6:

[0073] <Chemical Formula 2-1>

[0074]

[0075] <Chemical Formula 2-2>

[0076]

[0077] <Chemical Formula 2-3>

[0078]

[0079] <Chemical Formula 2-4>

[0080]

[0081] <Chemical Formula 2-5>

[0082]

[0083] <Chemical Formula 2-6>

[0084]

[0085] Among the above chemical formulas 2-1 to 2-6,

[0086] R 11 Inland R 14 , L1, a1, Vi, Y - , Z - , the description for each of n1 and n2 is the same as that for the above chemical formula 2. That is, the vinyl group, which is a polymerization portion between monomers, can be present at various positions of the benzene group in the above chemical formula 2.

[0087] R 11 and N + The bond of R can be a single bond or a double bond, 12 Wow N + The bond of R can be a single bond or a double bond, 13 and N + The bond of R can be a single bond or a double bond, 14 Wow N + The bond can be a single bond or a double bond. For example, R 11 and R 12 are combined with each other, and R 13 and R 14 R formed by combining with each other 11 -R 12 -N + -R 14 -R 13 -N + The group may be a pyrazine group.

[0088] For example, R 11 Inland R 14 If they are not combined with each other, then a1 is 1, so (L1) a1 This may exist. For another example, R 11 and R 12 are combined with each other and R 13 and R 14 are combined with each other and a1 is 0 (L1) a1 If this does not exist, a pyrazine group may exist. Another example is R 11 and R 12 are combined with each other and R 13 and R 14are combined with each other and a1 is 1 (L1) a1 If this exists, a bicyclo group may exist.

[0089] In one implementation, each of n, n1 and n2 can be selected from an integer from 1 to 10. For example, each of n, n1 and n2 can be 1, 2, 3, 4 or 5.

[0090] According to one embodiment, among the chemical formulae 2 and 2-1 to 2-6, at least one of n1 and n2 may be 1. For example, each of n1 and n2 may be 1.

[0091] According to one embodiment, among the chemical formulas 2 and 2-1 to 2-6 The group represented by can be represented by any one of the following chemical formulas 3-1 to 3-4:

[0092] <Chemical Formula 3-1>

[0093]

[0094] <Chemical Formula 3-2>

[0095]

[0096] <Chemical Formula 3-3>

[0097]

[0098] <Chemical Formula 3-4>

[0099]

[0100] Each of the above * and *' represents a bonding site with a neighboring atom.

[0101] According to one embodiment, the monomer may be at least one selected from the following compounds 1 to 5:

[0102]

[0103]

[0104]

[0105]

[0106] .

[0107] That is, the monomers are N1,N1,N2,N2-tetramethyl-N1,N2-bis(4-vinylbenzyl)ethane-1,2-diaminium (compound 1 above; may be referred to as TMVE), N1,N1,N6,N6-tetramethyl-N1,N6-bis(4-vinylbenzyl)hexane-1,6-diaminium (compound 2 above; may be referred to as TMVH), 1,4-bis(4-vinylbenzyl)pyrazine-1,4-diium (compound 3 above; may be referred to as VBP), 1,3-bis(4-vinylbenzyl)-1,3,5,7-tetraazaadamantane-1,3-diium (compound 4 above; may be referred to as VTAA), and It may be at least one selected from 1,4-bis(4-vinylbenzyl)-1,4-diazabicyclo[2.2.2]octane-1,4-diium (compound 5 above; may be referred to as VBDAO).

[0108] Among the above chemical formulas 2 and 2-1 to 2-6, "R 11 Inland R 14 "Not bonded to each other" may refer to the above chemical formula 3-1 or the above compounds 1 and 2.

[0109] Among the above chemical formulas 2 and 2-1 to 2-6, "R 11 and R 12 are combined with each other, and R 13 and R 14 "Combined with each other" may refer to the above chemical formulas 3-2 to 3-4 or the above compounds 3 to 5.

[0110] In the above chemical formulas 2 and 2-1 to 2-6, "a1 is 0, so (L1) a1This non-existence" can refer to the above chemical formula 3-2 or the above compound 2. Since a1 is 0 (L1) a1 If this does not exist, i) R 11 and R 12 are combined with each other, and ii) R 13 and R 14 can be combined with each other.

[0111] According to one implementation example, R 11 Inland R 14 are independently a substituted or unsubstituted C1-C5 alkyl group, a substituted or unsubstituted C2-C5 alkenyl group and -(CH2) n -N(Q1)(Q2) is selected, and each of Q1 and Q2 is hydrogen or a substituted or unsubstituted C1-C3 alkyl group, and n can be 0, 1 or 2. For example, R 11 Inland R 14 can be independently selected from a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, an i-butyl group, an s-butyl group, a tert-butyl group, an ethenyl group, a propenyl group, a butenyl group, -CH2-NHCH3, and -CH2-N(CH3)2.

[0112] According to one embodiment, L1 is substituted or unsubstituted C1-C 10 It can be an alkylene group. For example, L1 is -CH2-, -(CH2)2-, -(CH2)3-, -(CH2)4-, -(CH2)5-, -(CH2)6-, -(CH2)7-, -(CH2)8-, -(CH2)9-, and -(CH2) 10 - can be selected from among.

[0113] Vi is It can be a group marked with , and * is a bonding site with a neighboring atom.

[0114] Y - and Z - may be identical or different. For example, Y - and Z - Each is Cl - It could be.

[0115] According to one embodiment, the monomer may comprise two to four nitrogens. For example, the monomer may comprise two N + may include. For another example, the monomer may include two N + and may contain two Ns.

[0116] According to one embodiment, the composition including the monomer represented by the above chemical formula 2 may further include a photoinitiator. The photoinitiator may be at least one selected from 2-hydroxy-2-methylpropiophenone, 2-hydroxy-4-(2-hydroxyethoxy)-2-methylpropiophenone, and 1-hydroxy-cyclohexyl-phenyl-ketone.

[0117] anion exchange membrane

[0118] According to one embodiment, the weight of the first polymer included in the anion exchange membrane may be greater than the weight of the second polymer included in the anion exchange membrane. For example, the weight of the first polymer to the weight of the second polymer may be 5:0.1 to 5:4. Specifically, the weight of the first polymer included in the anion exchange membrane may be greater than twice the weight of the second polymer included in the anion exchange membrane. The weight of the first polymer to the weight of the second polymer may be 5:0.5 to 5:2 or 5:1 to 5:2.

[0119] According to one embodiment, the anion exchange membrane may be a free-standing film. The anion exchange membrane may be a single-layer membrane. That is, the anion exchange membrane does not include a separate substrate (support). For example, the first polymer or the second polymer may be present in any portion of the anion exchange membrane.

[0120] In one embodiment, the anion exchange membrane may not include a porous polymer support. For example, the anion exchange membrane may not include polyethylene, polypropylene, polyethylene terephthalate, polyvinyl alcohol, polybenzimidazole, polyarylene sulfide, polyetheretherketone, polyethersulfone, polysulfone, polystyrene, polyarylene ethersulfone, and polyetherketone.

[0121] According to one embodiment, the sheet resistance of the anion exchange membrane measured at 25°C and in 1 M potassium hydroxide is 0.1Ω·cm. 2 Within 1Ω·cm 2 It can be. The above surface resistance can be calculated according to Evaluation Example 1 described below. For example, the surface resistance of the anion exchange membrane calculated according to Evaluation Example 1 at 25°C and in 1 M potassium hydroxide is 0.15Ω·cm. 2 Within 0.5Ω·cm 2 or 0.2Ω·cm 2 Within 0.4Ω·cm 2 It could be.

[0122] According to one embodiment, the ionic conductivity of the anion exchange membrane measured at 25°C and in 1 M potassium hydroxide may be 5 mS / cm to 80 mS / cm. The ionic conductivity may be calculated according to Evaluation Example 2 described below. For example, the ionic conductivity of the anion exchange membrane calculated according to Evaluation Example 2 at 25°C and in 1 M potassium hydroxide may be 5.5 mS / cm to 70 mS / cm, 6 mS / cm to 60 mS / cm, 6.5 mS / cm to 50 mS / cm, 7 mS / cm to 40 mS / cm, 7.5 mS / cm to 35 mS / cm, or 8 mS / cm to 30 mS / cm.

[0123] According to one embodiment, the ion exchange capacity of the anion exchange membrane may be 1.0 meq / g to 3.0 meq / g. The ion exchange capacity may be calculated according to Evaluation Example 3 described below. For example, the ion exchange capacity of the anion exchange membrane may be 1.5 meq / g to 3.0 meq / g, 1.8 meq / g to 3.0 meq / g, 1.5 meq / g to 2.5 meq / g, or 1.8 meq / g to 2.5 meq / g.

[0124] According to one embodiment, the thickness of the anion exchange membrane may be 30 μm to 100 μm. For example, the thickness of the anion exchange membrane may be 40 μm to 80 μm or 50 μm to 70 μm. If the thickness of the anion exchange membrane is outside the above-described range, the durability and mechanical stability, sheet resistance, ionic conductivity, ion exchange capacity, current density, and other physical properties of the anion exchange membrane may deteriorate.

[0125] Method for manufacturing anion exchange membrane

[0126] According to another aspect,

[0127] A step of mixing the first polymer and the monomer into a solvent;

[0128] A step of casting the mixture onto a substrate;

[0129] A step of forming a film by irradiating the cast mixture with ultraviolet rays; and

[0130] A method for manufacturing an anion exchange membrane is provided, including a step of peeling the substrate from the film.

[0131] The solvent may be a co-solvent including a first solvent that dissolves the first polymer and a second solvent that dissolves the monomer. An example of the first solvent may be 1-methyl-2-pyrrolidone, and an example of the second solvent may be methanol.

[0132] Examples of the above materials include glass plates, polyester films, and stainless steel (SUS).

[0133] Since the method for manufacturing the above anion exchange membrane includes a step of peeling off the substrate, the manufactured anion exchange membrane does not include the substrate (support). For example, the substrate can be peeled off from the film by immersing the substrate and the film attached to the substrate in water or a potassium hydroxide (KOH) solution, etc.

[0134] According to one embodiment, the ultraviolet rays may be selected from ultraviolet A (UVA), ultraviolet B (UVB), ultraviolet C (UVC), and vacuum ultraviolet (VUV). The intensity of the ultraviolet rays is 2,000 mJ / cm 2 Up to 10,000 mJ / cm 2 It could be.

[0135] According to one embodiment, the method for manufacturing an anion exchange membrane may further include a step of drying the composition or the film at a temperature higher than room temperature for at least 1 minute to evaporate the solvent. For example, drying may be performed at 50°C to 100°C or 60°C to 80°C for 5 to 60 minutes or 10 to 30 minutes.

[0136] Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

[0137] Example A1

[0138] The first polymer is dissolved in a mixed solvent of 1-methyl-2-pyrrolidone and methanol at 25 wt% of the total solution amount at 60°C, and then compound 1 is added at room temperature and stirred. At this time, the weight of the first polymer to the weight of compound 1 is 5:1. After the first polymer and compound 1 are completely dissolved, 2-hydroxy-2-methylpropiophenone is added as a photoinitiator at 1 wt% of the total solution amount, and then stirred for an additional 10 minutes.

[0139] After melting is complete, the mixture is cast onto the substrate using blade or slot die equipment.

[0140] After casting, the mixture was exposed to 3000 mJ / cm 2 Compound 1 is crosslinked by irradiating it with UVC ultraviolet rays of a high intensity. Thereafter, the solvent is evaporated by drying in a hot air oven at 70°C for 20 minutes to form a film. The film attached to the substrate is immersed in water or potassium hydroxide (KOH) to peel the substrate from the film, thereby producing an anion exchange membrane having a thickness of 70 μm.

[0141] Examples A2 to A5

[0142] An anion exchange membrane was prepared in the same manner as in Example A1, except that the compound described in Table 1 below was used instead of the compound 1 above.

[0143] Comparative Example A1 (excluding second polymer)

[0144] The first polymer is dissolved in a mixed solvent of 1-methyl-2-pyrrolidone and methanol at 25 wt% of the total amount of the solution at 60°C, and then cooled to room temperature.

[0145] Afterwards, the mixture is cast onto a substrate using a blade or slot die. The film is dried in a hot air oven at 70°C for 20 minutes to evaporate the solvent, thereby forming a film. The film attached to the substrate is immersed in water or potassium hydroxide (KOH) to peel the substrate from the film, thereby producing a 70 μm thick anion exchange membrane.

[0146] Comparative examples A2 to A6 (excluding the first polymer)

[0147] As a monomer of the second polymer, the compound described in Table 1 below is dissolved in a mixed solvent of 1-methyl-2-pyrrolidone and methanol at 25 wt% of the total amount of the solution. After the compound is completely dissolved, 2-hydroxy-2-methylpropiophenone is added as a photoinitiator at 1 wt% of the total amount of the solution, and the mixture is stirred for approximately 10 minutes.

[0148] After melting is complete, the mixture is cast onto the substrate using blade or slot die equipment.

[0149] After casting, the mixture was exposed to 3000 mJ / cm 2 Compound 1 is crosslinked by irradiating it with UVC ultraviolet rays of high intensity. Afterwards, it is dried in a hot air oven at 70°C for 20 minutes.

[0150] Comparative Examples B1 to B5 (including porous polymer support instead of first polymer)

[0151] A polypropylene (PP) porous polymer support (porosity: 51%) with a thickness of 60 ㎛ was prepared.

[0152] As a monomer of the second polymer, the compound described in Table 2 below was dissolved in a mixed solvent of 1-methyl-2-pyrrolidone and methanol at 25 wt% of the total amount of the solution. After the compound was completely dissolved, 2-hydroxy-2-methylpropiophenone was added as a photoinitiator at 1 wt% of the total amount of the solution, and the mixture was stirred for approximately 10 minutes to prepare a composition.

[0153] The hydrophilized porous polymer support was immersed in the composition for 5 minutes to fill the surface and interior of the pores of the porous polymer support with the composition.

[0154] A polyester film having a thickness of 50 μm was pressed onto the upper and lower surfaces of the porous polymer support filled with the above composition to manufacture a laminate in which the polyester film and the porous polymer support were combined.

[0155] 3000mJ / cm to the above laminate 2 A second polymer, which is a polymer or copolymer of the compound present on the surface and inside the pores of the porous polymer support, was formed by irradiating the porous polymer support with UVC ultraviolet rays of a high intensity. An anion exchange membrane was manufactured by peeling the polyester film from the porous polymer support in which the second polymer was formed on the surface and inside the pores.

[0156] Examples C1-1 to C5-2 and Comparative Examples C1-1 to C5-2 (thickness of anion exchange membrane)

[0157] An anion exchange membrane was manufactured in the same manner as Example A1, except that the compounds described in Table 3 below were used as monomers of the second polymer and the thickness of the anion exchange membrane was the value described in Table 3 below.

[0158] Evaluation Example 1 (Surface Resistance)

[0159] Each anion exchange membrane specimen was cut into 5 cm × 5 cm pieces to prepare a sample. The sample was immersed in a 1 M KOH solution for more than 12 hours. The measured value was stabilized by placing it between electrodes for measuring surface resistance under the conditions of a 1 M KOH solution.

[0160] The sample was placed between electrodes for measuring surface resistance, and the line resistance (R1) of the anion exchange membrane was measured using an LCR meter (Agilent, E4980A). After removing the anion exchange membrane, the resistance (R2) of a 1 M KOH solution was measured. The surface resistance of the anion exchange membrane was calculated using Equation 1 below.

[0161] <Formula 1>

[0162] Rm = (R1 - R2) × S

[0163] In the above formula 1,

[0164] Rm is the surface resistance of the anion exchange membrane (Ω·cm) 2 ) and,

[0165] R1 is the line resistance of the anion exchange membrane,

[0166] R2 is the resistance of 1M KOH solution,

[0167] S is the area of ​​the electrode.

[0168] Evaluation Example 2 (Ionic Conductivity)

[0169] The ionic conductivity was calculated by substituting the surface resistance (Rm) of the anion exchange membrane calculated in the above evaluation example 1 into Equation 2 below.

[0170] <Formula 2>

[0171] Ionic conductivity (mS / cm) = [thickness of anion exchange membrane (㎛) / Rm (Ω·cm) 2 )] / 10

[0172] Evaluation Example 3 (Ion Exchange Capacity)

[0173] Each anion exchange membrane was cut into 5 cm X 5 cm sizes to prepare samples. The samples were washed with distilled water and excess moisture was removed with a tissue. After filling a vial with 70 mL of a 1 M NaCl solution, the sample from which moisture had been removed was placed in the 1 M NaCl solution and immersed for more than 12 hours to perform the first pretreatment. Afterwards, the sample from which moisture had been removed was washed several times with distilled water and excess moisture was removed with a tissue. After filling a vial with 70 mL of a 0.5 M Na2CO3 solution, the sample from which moisture had been removed was placed in the 0.5 M Na2CO3 solution and immersed for more than 12 hours to perform the second pretreatment. Afterwards, the sample from which the second pretreatment had been completed was taken out of the vial, and the remaining solution was titrated with a 0.01 M AgNO3 solution, and the volume of the AgNO3 solution added during the titration was recorded. The sample was washed several times with distilled water and then dried in a hot air oven at 70°C for more than 1 hour. After drying was complete, the weight of the dried anion exchange membrane was measured. The measured weight of the dried anion exchange membrane was substituted into Equation 3 below to obtain the ion exchange capacity (IEC).

[0174] <Formula 3>

[0175] IEC (meq / g) = [volume of titrant (mL) x 0.01] / weight of dried anion exchange membrane (g)

[0176] Evaluation Example 4 (Current Density)

[0177] Each anion exchange membrane specimen was cut into 5 cm × 5 cm sizes to prepare a sample. The sample was pretreated by immersing it in a 1 M KOH solution at room temperature for 12 hours, and then the current density was measured by constantly applying a voltage of 1.5 V to 2 V using a water electrolysis system and recording the current value.

[0178] Evaluation Example 5 (Appearance Evaluation)

[0179] For each anion exchange membrane, the appearance was visually observed and evaluated using the following criteria.

[0180] ·Good: Smooth surface, no cracks or peeling

[0181] ·Defective: Surface is not smooth, cracks or peeling occur

[0182] Evaluation Example 6 (Leak Evaluation)

[0183] Each anion exchange membrane specimen was cut to a size of 5 cm × 5 cm to prepare a sample. After the sample was connected to the unit cell, hydrogen at a pressure of 20 kPa was injected into the cathode (at this time, the anode side port was open and the state was the same as atmospheric pressure). The unit cell was left to stand for more than 5 minutes to allow the internal pressure to stabilize. The hydrogen pressure was measured with a manometer 1 minute later on the opposite side of the anion exchange membrane from the point where the hydrogen was injected.

[0184] No. Thickness (㎛) of monomer anion exchange membrane of polymer No. 1 and polymer No. 2, surface resistance (Ω·cm) 2)Ionic conductivity (mS / cm)Ion exchange capacity (meq / g)Current density (mA at 1.8 V)Appearance evaluationLeakage evaluation (Barrer at 10 bar)Example A1Chemical formula 1Compound 1700.25282.11000Good5Example A2Chemical formula 1Compound 2700.27262.01000Good6Example A3Chemical formula 1Compound 3700.37192.0800Good4Example A4Chemical formula 1Compound 4700.42172.0950Good4Example A5Chemical formula 1Compound 5700.25282.21000Good4Comparative Example A1Chemical formula 1-700.18391.5600Good30Comparative Example A2-Compound 1 film formation is not possible. Comparative example A3-Compound 2. Comparative example A4-Compound 3. Comparative example A5-Compound 4. Comparative example A6-Compound 5

[0185] From Table 1 above, in Comparative Examples A2 to A6 where the first polymer having the repeating unit represented by Chemical Formula 1 was not used, membrane formation was impossible. This indicates that when the second polymer using the monomer represented by Chemical Formula 2 is used without the first polymer, a separate configuration is required for application as an anion exchange membrane. Accordingly, Comparative Examples B1 to B5 where a separate configuration is applied are described below with reference to Table 2 below.

[0186] The anion exchange membranes manufactured by Examples A1 to A5 had a dielectric constant of 0.05Ω·cm 2 It has a low surface resistance of the level below and a high ionic conductivity of 15 mS / cm or more, and has a higher ion exchange capacity than the anion exchange membrane according to Comparative Example A1 using the first polymer without the second polymer, and it can be seen that it has a low hydrogen permeability as seen from the low hydrogen pressure by leak evaluation.

[0187] No. Thickness (㎛) of the monomer anion exchange membrane of the second polymer, porous support material, surface resistance (Ω·cm) 2)Ionic conductivity (mS / cm)Ion exchange capacity (meq / g)Current density (mA at 1.8V)Appearance evaluationLeakage evaluation (Barrer at 10 bar)Comparative example B1PP compound 1701.74.11.0137Good0Comparative example B2PP compound 2701.25.81.0208Good0Comparative example B3PP compound 3701.83.91.1127Good0Comparative example B4PP compound 4701.35.41.7265Good0Comparative example B5PP compound 5701.25.81.6280Good0

[0188] Since a self-supporting anion exchange membrane cannot be manufactured when a second polymer using a monomer represented by the above chemical formula 2 is used without the above first polymer, an anion exchange membrane in which the second polymer exists on the surface and inside the pores of a porous polymer support can be manufactured and the physical properties can be compared.

[0189] Referring to Tables 1 and 2 above, it can be seen that the anion exchange membranes manufactured by Examples A1 to A5 including the first polymer and the second polymer without a porous polymer support have lower sheet resistance, higher ion conductivity, higher ion exchange capacity, and higher current density than the anion exchange membranes manufactured by Comparative Examples B1 to B5 using a porous polymer support instead of the first polymer.

[0190] No. Thickness (㎛) of monomer anion exchange membrane of polymer No. 1 and polymer No. 2, surface resistance (Ω·cm) 2)Ionic conductivity (mS / cm)Ion exchange capacity (meq / g)Current density (mA at 1.8 V)Appearance evaluationLeakage evaluation (Barrer at 10 bar)Example C1-1 Chemical formula 1 Compound 1300.2151.91050Good17Example C1-2 Chemical formula 1 Compound 11000.3332.2920Good4.8Comparative example C1-1 Chemical formula 1 Compound 120Unable to measure due to weak durabilityPoorUnable to measure due to weak durabilityComparative example C1-2 Chemical formula 1 Compound 11100.42262.2780Good4Example C2-1 Chemical formula 1 Compound 2300.25121.91020Good18Example C2-2 Chemical formula 1 Compound 21000.3332.1905 Good 5.8 Comparative Example C2-1 Chemical Formula 1 Compound 220 Cannot be measured due to weak durability Poor Cannot be measured due to weak durability Comparative Example C2-2 Chemical Formula 1 Compound 21100.31352.2729 Good 4.2 Example C3-1 Chemical Formula 1 Compound 3300.358.61.8810 Good 12 Example C3-2 Chemical Formula 1 Compound 31000.41242.1708 Good 3.8 Comparative Example C3-1 Chemical Formula 1 Compound 3200.3361.8800 Good 15 Comparative Example C3-2 Chemical Formula 1 Compound 31100.48232.1625 Good 3.8 Example C4-1 Chemical Formula 1 Compound 4300.387.91.8970 Good 19 Example C4-2 Chemical Formula 1 Compound 41000.50202.0803 Good 4 Comparative Example C4-1 Chemical Formula 1 Compound 4200.375.41.7992 Good 22 Comparative Example C4-2 Chemical Formula 1 Compound 41100.58192.1725 Good 3.7 Example C5-1 Chemical Formula 1 Compound 5300.23132.01020 Good 17 Example C5-2 Chemical Formula 1 Compound 51000.27372.3952 Good 3.9 Comparative Example C5-1 Chemical Formula 1 Compound 5200.20101.91005 Good 24 Comparative Example C5-2 Chemical Formula 1 Compound 51100.30372.3874 Good 3.8

[0191] Referring to Tables 1 and 3 above, it can be seen that the anion exchange membranes manufactured by Examples A1 to A5 and C1-1 to C5-2 and having a thickness of 30 μm to 100 μm have stronger durability, lower surface resistance, higher current density, higher ion exchange capacity, and / or lower hydrogen permeability than the anion exchange membranes manufactured by Comparative Examples C1-1 to C5-2 and having a thickness outside the range of 30 μm to 100 μm.

[0192] From the above-described evaluation examples 1 to 6, it can be seen that the anion exchange membranes manufactured by examples A1 to A5 and C1-1 to C5-2 are suitable for use in electrodialysis, bipolar membrane electrodialysis, electrodeionization, capacitive deionization, or water electrolysis.

[0193] The above description is provided for illustrative purposes only, and those skilled in the art will readily appreciate that the present invention can be readily modified into other specific forms without altering the technical spirit or essential characteristics of the present invention. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive.

Claims

1. A first polymer having a repeating unit represented by the following chemical formula 1; and A second polymer, which is a polymer or copolymer of a composition including a monomer represented by the following chemical formula 2; The above second polymer is entangled in the network formed by the above first polymer to form a semi-interpenetrating polymer network (semi-IPN) structure, an anion exchange membrane: <Chemical Formula 1> <Chemical Formula 2> Among the above chemical formulas 1 and 2, R 1 Inland R 3 and R 11 Inland R 14 are independently substituted or unsubstituted C 1 -C 20 Alkyl group, substituted or unsubstituted C 2 -C 20 Alkenyl group and -(CH 2 ) n -N(Q 1 )(Q 2 ) are selected from among Q 1 and Q 2 Each is hydrogen or substituted or unsubstituted C 1 -C 3 It is an alkyl group, R 11 And R 12 , R 11 And R 13 , R 11 And R 14 , R 12 Wow R 13 , R 12 Wow R 14 and R 13 And R 14 Each of them is optionally combined with the other, L 1 is a single bond and substituted or unsubstituted C 1 -C 20 Selected from alkylene groups, a1 is 0 or 1, and if a1 is 0 (L 1 ) a1 does not exist and i) R 11 And R 12 and ii) R 13 And R 14 At least one of them is combined with each other, Vi is vinyl group, X - , Y - and Z - are independent of each other, F - , Cl - , Br - and I - Selected from among, p is selected from 60 to 80, q is selected from 20 to 40, The sum of p and q is 100, Each of n, n1, and n2 is selected from integers greater than or equal to 1.

2. In paragraph 1, R 1 Inland R 3 Each is substituted or unsubstituted C 1 -C 20 Alkyl group, anion exchange membrane.

3. In paragraph 1, The above monomer is an anion exchange membrane represented by any one of the following chemical formulas 2-1 to 2-6: <Chemical Formula 2-1> <Chemical Formula 2-2> <Chemical Formula 2-3> <Chemical Formula 2-4> <Chemical Formula 2-5> <Chemical Formula 2-6> .

4. In paragraph 1, An anion exchange membrane, wherein at least one of n1 and n2 is 1.

5. In paragraph 1, Among the chemical formula 2 above The group represented by is an anion exchange membrane represented by any one of the following chemical formulas 3-1 to 3-4: <Chemical Formula 3-1> <Chemical Formula 3-2> <Chemical Formula 3-3> <Chemical Formula 3-4> Each of the above * and *' represents a bonding site with a neighboring atom.

6. In paragraph 1, The above monomer is an anion exchange membrane, wherein at least one compound is selected from the following compounds 1 to 5: .

7. In paragraph 1, An anion exchange membrane, wherein the weight of the first polymer to the weight of the second polymer is 5:0.1 to 5:

4.

8. In paragraph 1, The above composition further comprises a photoinitiator, An anion exchange membrane, wherein the photoinitiator is at least one selected from 2-hydroxy-2-methylpropiophenone, 2-hydroxy-4-(2-hydroxyethoxy)-2-methylpropiophenone, and 1-hydroxy-cyclohexyl-phenyl-ketone.

9. In paragraph 1, The above anion exchange membrane is a free-standing film.

10. In paragraph 1, The above anion exchange membrane is an anion exchange membrane that does not contain a porous polymer support.

11. In paragraph 1, The surface resistance is 0.1Ω cm at 25℃ and in 1M potassium hydroxide. 2 Within 1Ω·cm 2 In, anion exchange membrane.

12. In paragraph 1, An anion exchange membrane having an ionic conductivity of 5 mS / cm to 80 mS / cm in 1 M potassium hydroxide at 25°C.

13. In paragraph 1, An anion exchange membrane having an ion exchange capacity of 1.0 meq / g to 3.0 meq / g.

14. In paragraph 1, An anion exchange membrane having a thickness of 30 μm to 100 μm.

15. A step of mixing the first polymer of paragraph 1 and the monomer of paragraph 1 into a solvent; A step of casting the mixture onto a substrate; A step of forming a film by irradiating the cast mixture with ultraviolet rays; and A method for manufacturing an anion exchange membrane, comprising a step of peeling the substrate from the film.

16. In paragraph 15, A method for manufacturing an anion exchange membrane, wherein the above ultraviolet rays are selected from ultraviolet A (UVA), ultraviolet B (UVB), ultraviolet C (UVC), and vacuum ultraviolet (VUV).

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