Anion exchange membrane and method for producing the same

Abstract

An anion exchange membrane and a method for producing the same are disclosed. The anion exchange membrane includes a porous polymer support composed of a membrane structure, and an anion exchange polymer. The anion exchange polymer is located on the surface of the porous polymer support and inside the pores, and the anion exchange groups of the anion exchange polymer are uniformly distributed on the surface of the porous polymer support and inside the pores. The anion exchange polymer is a cross-linked product of a composition containing a cross-linkable monomer represented by the following chemical formula 1: [Chemical Formula 1] In Chemical Formula 1, X in JPEG2025523983000012.jpg72170 - is as disclosed in the specification.

Description

Technical Field

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

Background Art

[0002] An ion exchange membrane refers to a synthetic resin membrane that selects cations and anions and allows only one type of ion to permeate. Among them, an anion exchange membrane has a positively charged functional group and is a synthetic resin membrane that selects and permeates anions. Such an anion exchange membrane is applied to water treatment systems such as electrodialysis, bipolar membrane electrodialysis, energy storage desalination, and electro-deionization, or can be applied to systems such as fuel cells, water electrolysis, reverse electrodialysis, and redox flow batteries. Systems to which the anion exchange membrane is applied can apply acid or alkaline raw water to the process, and acid or alkali can be generated during the process operation of the raw water. Here, a perfluorinated anion exchange membrane can be used as the anion exchange membrane, but it is expensive, and a hydrocarbon-based anion exchange membrane is applied in actual systems. However, hydrocarbon-based anion exchange membranes have limitations in the application processes and conditions due to chemical resistance problems. In addition, since a certain portion of the support fraction exists in the membrane in the anion exchange membrane, there is a limit to increasing the ion exchange capacity in order to improve the membrane physical properties.

Summary of the Invention

Problems to be Solved by the Invention

[0003] One aspect is to provide an anion exchange membrane having a low sheet resistance, a high ion exchange capacity, and excellent chemical resistance in the presence of high-concentration acid and alkali.

[0004] Another aspect is to provide a method for producing the anion exchange membrane.

Means for Solving the Problems

[0005] According to one aspect, a porous polymer support comprising a membrane structure, An anion exchange polymer, and the anion exchange polymer is located on the surface of the porous polymer support and inside the pores, the anion exchange groups of the anion exchange polymer are uniformly distributed on the surface of the porous polymer support and inside the pores, an anion exchange membrane is provided, which is a cross-linked product of a composition containing a cross-linkable monomer represented by the following Chemical Formula 1:

[0006] [Chemical Formula]

[0007] In Chemical Formula 1, X - is F - , Cl - , Br - , or I - .

[0008] The membrane structure has a structure in which pores are regularly arranged or is also a three-dimensional network structure.

[0009] The porosity of the membrane structure is also 30% to 80%.

[0010] The membrane structure may include one or more polymers selected from polyethylene, polypropylene, polyethylene terephthalate, polyvinyl alcohol, polybenzimidazole, polyarylene sulfide, polyether ether ketone, polyether sulfone, polysulfone, polystyrene, polyarylene ether sulfone, and polyether ketone.

[0011] The thickness of the porous polymer support is also 10 μm to 110 μm.

[0012] The average thickness of the anion exchange membrane is also 10 μm to 200 μm.

[0013] The ion exchange capacity of the anion exchange membrane is also 1.5 meq / g or more.

[0014] The sheet resistance of the anion exchange membrane is 10 Ω·cm 2 or less.

[0015] The anion exchange membrane can be used in electrodialysis, bipolar membrane electrodialysis, electrodeionization, capacitive deionization, and water electrolysis systems.

[0016] According to another aspect, providing a porous polymer support comprising a membrane structure; manufacturing a composition for forming an anion exchange polymer, the composition comprising a crosslinkable monomer represented by the following Chemical Formula 1, a photoinitiator, and a solvent; impregnating the porous polymer support with the composition for forming an anion exchange polymer to fill the surface and the inside of the pores of the porous polymer support with the composition; pressing a polyester film onto at least one surface of the porous polymer support filled with the composition to manufacture a laminate in which the polyester film and the porous polymer support are laminated together; irradiating the laminate with light to cause a crosslinking reaction of the composition to form an anion exchange polymer, which is a crosslinked product of the composition, on the surface and the inside of the pores of the porous polymer support; peeling the polyester film from the porous polymer support having the anion exchange polymer formed on the surface and the inside of the pores to manufacture an anion exchange membrane. A method for manufacturing an anion exchange membrane is provided, the method including:

[0017]

Chemical formula

[0018] In Chemical Formula 1, X - is F - , Cl - , Br - , or I - .

[0019] The content of the crosslinkable monomer represented by the chemical formula 1 is also 30% by weight to 70% by weight based on 100% by weight of the whole of the composition for forming the anion exchange polymer.

[0020] Before impregnating the porous polymer support into the composition for forming the anion exchange polymer, the porous polymer support may be further immersed in a surfactant solution, dried, and a porous polymer support having a hydrophilic surface may be produced.

[0021] The irradiation of the light may be performed with UVC as ultraviolet light at a light quantity of 2000 mJ / cm 2 to 10,000 mJ / cm 2 .

[0022] An anion exchange membrane according to one aspect is an anion exchange polymer which is a crosslinked product of a composition containing a crosslinkable monomer represented by the above chemical formula 1, and is located on the surface and inside the pores of a porous polymer support composed of a membrane structure, and the anion exchange groups of the anion exchange polymer are uniformly distributed on the surface and inside the pores of the porous polymer support.

[0023] The anion exchange membrane can increase the content of the anion exchange polymer in the anion exchange membrane and has a high ion exchange capacity and a low sheet resistance. Further, the anion exchange membrane is excellent in chemical resistance and can be used under conditions of high-concentration acids and alkalis.

Brief Description of the Drawings

[0024]

Figure 1

Figure 2

Figure 3

Figure 4

Mode for Carrying Out the Invention

[0025] Hereinafter, with reference to the examples and drawings of the present invention, an anion exchange membrane and a method for manufacturing the same will be described in detail. It will be apparent to those having ordinary knowledge in the art that those examples are only presented illustratively to explain the present invention more specifically, and the scope of the present invention is not limited by those examples.

[0026] 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 belongs. In case of conflict, the present specification, including definitions, will control. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, the suitable methods and materials are described herein. As used herein, the term "comprising" means including other components and not excluding other components, unless specifically stated to the contrary. As used herein, the term "a combination thereof" means a mixture or combination with one or more of the described components. As used herein, the term "and / or" means any and all combinations of one or more of the associated listed items. As used herein, the term "or" means "and / or". As used herein, the expressions "at least one kind" or "one or more" before a component do not mean that the list of all components can be supplemented or the individual components mentioned above can be supplemented. As used herein, when a component is referred to as being "on" or "above" another component, the component can be directly disposed on the other component or there can be a component intervening between the components. On the other hand, when a component is referred to as being "directly on" or "directly above" another component, there is no intervening component. As used herein, the terms "~-based resin", "~-based polymer", "~-based polymer", and / or "~-based copolymer" are broad concepts that include any of "~ resin", "~ polymer", "~ polymer", "~ copolymer", and / or "derivatives of ~ resin, ~ polymer, ~ polymer, or ~ copolymer". As used herein, the term "a polymer or copolymer crosslinked to those resins" means "a polymer or copolymer crosslinked to the aforementioned resins".

[0027] Figure 1 is a conceptual diagram of a general anion exchange membrane.

[0028] Referring to FIG. 1, the anion exchange membrane 10 has an anion exchange polymer main chain 2 having a cationic functional group 1 disposed on a support 5. When the anion exchange membrane 10 allows the counter anion 3 and the co-cation 4 to permeate from the left side to the right side, the counter anion 3 selectively permeates.

[0029] Generally, the anion exchange membrane 10 is required to have high permeation selectivity, low electrical resistance, excellent mechanical strength, high chemical stability, etc. As materials for the anion exchange membrane 10, there are perfluorinated anion exchange membranes and hydrocarbon-based anion exchange membranes. Among them, the hydrocarbon-based anion exchange membrane has excellent price competitiveness, but has weak chemical resistance and limitations in application processes and conditions. In addition, the hydrocarbon-based anion exchange membrane has a certain portion of the support fraction, and there is a limit to increasing the ion exchange capacity for enhancing the membrane performance.

[0030] Focusing on such points, the inventors of the present invention propose the following anion exchange membrane and its manufacturing method.

[0031] An anion exchange membrane according to an embodiment includes a porous polymer support made of a membrane structure, and an anion exchange polymer, wherein the anion exchange polymer is located on the surface and inside the pores of the porous polymer support, and the anion exchange groups of the anion exchange polymer are uniformly distributed on the surface and inside the pores of the porous polymer support, and the anion exchange polymer is a cross-linked product of a composition containing a cross-linkable monomer represented by the following Chemical Formula 1:

[0032]

Chemical formula

[0033] In Chemical Formula 1, X - is F - , Cl - , Br - or I - and is.

[0034] The anion exchange membrane according to one embodiment can increase the content of the anion exchange polymer in the anion exchange membrane and can have a high ion exchange capacity and a low sheet resistance. Further, the anion exchange membrane is excellent in chemical resistance and can be used under conditions of high-concentration acids and alkalis.

[0035] FIG. 2 is a schematic diagram of an anion exchange membrane according to one embodiment.

[0036] Referring to FIG. 2, in an anion exchange membrane 40 according to one embodiment, an anion exchange polymer 31 having a cationic functional group is disposed on the surface of a porous polymer support 20 and inside pores 21. The anion exchange polymer 31 having a cationic functional group is uniformly distributed on the surface of the porous polymer support 20 and inside the pores 21, and a homogeneous anion exchange membrane 40 can be obtained. Such a structure of the anion exchange membrane 40 can have a low sheet resistance and a high ion conductivity. Further, the porous polymer support 20 can improve mechanical durability and have high dimensional stability.

[0037] The anion exchange polymer is a cross-linked product of a composition containing the cross-linkable monomer represented by Chemical Formula 1. The cross-linkable monomer represented by Chemical Formula 1 is a monomer in which two vinylbenzyl chlorides are cross-linked to a bi-functional cyclic diamine containing pendant chains to which quaternary ammonium cation groups are attached. The cross-linkable monomer represented by Chemical Formula 1 forms a rigid cage structure and can improve the ion exchange capacity while having chemical stability even under conditions of high-concentration acids or alkalis. Therefore, an anion exchange membrane containing such an anion exchange polymer can have excellent concentration and desalination performance. The "cross-linked product" means a product that includes any of an initial reaction product, an intermediate reaction product, and a final reaction product, in addition to a cured product of a composition containing the cross-linkable monomer represented by Chemical Formula 1.

[0038] The membrane structure has a structure in which pores are regularly arranged or is a three-dimensional network structure. The structure of such a membrane structure can be confirmed by FIG. 3 described later. For example, the membrane structure is formed by mixing a polymer material and a low molecular weight wax, extruding it into a film at a high temperature, and then extracting the wax using a solvent to form a microporous structure, or without using wax, a pore structure can be formed by a uniaxial or biaxial stretching and heat treatment process. However, it is not limited thereto, and the membrane structure can be formed by all manufacturing methods usable in the technical field.

[0039] The porosity of the membrane structure is 30% to 80%. For example, the porosity of the membrane structure is 35% to 70%, 40% to 65%, 45% to 60%, or 45% to 55%. If the pore size and / or porosity of the membrane structure is less than 30%, it is difficult to improve the physical durability and mechanical strength of the anion exchange membrane to be obtained as a porous polymer support. If the pore size and / or porosity of the membrane structure exceeds 80%, the fraction occupied by the porous polymer support in the anion exchange membrane becomes excessive, the sheet resistance increases, and the ion exchange capacity may decrease.

[0040] The membrane structure contains one or more polymers selected from polyethylene, polypropylene, polyethylene terephthalate, polyvinyl alcohol, polybenzimidazole, polyarylene sulfide, polyether ether ketone, polyether sulfone, polysulfone, polystyrene, polyarylene ether sulfone, and polyether ketone. For example, the membrane structure is polyethylene or polypropylene. For example, the membrane structure is polypropylene.

[0041] The thickness of the porous polymer support is 10 μm to 110 μm. For example, the thickness of the porous polymer support is 20 μm to 110 μm, 40 μm to 110 μm, or 60 μm to 110 μm. Within the thickness range of the porous polymer support, the sheet resistance can decrease and the ion exchange capacity can increase.

[0042] The average thickness of the anion exchange membrane is 10 μm to 200 μm. For example, the average thickness of the anion exchange membrane is 12 μm to 150 μm. If the average thickness of the anion exchange membrane is less than 10 μm, the physical durability and handleability of the anion exchange membrane will decrease, and there is a risk that the membrane will be damaged during module assembly or after system application during operation, and the system operation performance may decrease due to the permeation of unnecessary ions. When the average thickness of the anion exchange membrane exceeds 200 μm, the sheet resistance will increase, and when applied to a system or the like, the power consumption required for operation will increase, and the system operation performance may decrease.

[0043] The ion exchange capacity of the anion exchange membrane is 1.5 meq / g or more. For example, the ion exchange capacity of the anion exchange membrane is 1.6 meq / g or more, 1.7 meq / g or more, 1.8 meq / g or more, 1.9 meq / g or more, 2.0 meq / g or more, 2.1 meq / g or more, 2.2 meq / g or more, 2.3 meq / g or more, or 2.4 meq / g or more.

[0044] The sheet resistance of the anion exchange membrane is 10 Ω·cm 2 or less. For example, the sheet resistance of the anion exchange membrane is 9.9 Ω·cm 2 or less, 9.8 Ω·cm 2 or less, 9.7 Ω·cm 2 or less, 9.6 Ω·cm 2 or less, 9.0 Ω·cm 2 or less, 8.5 Ω·cm 2 or less, 8.0 Ω·cm 2 or less, 7.8 Ω·cm 2 or less, 7.6 Ω·cm 2 or less, 7.2 Ω·cm 2 or less, 6.5 Ω·cm 2 or less, 6.0 Ω·cm2 Less than or equal to 5.0 Ω·cm 2 Less than or equal to 4.0 Ω·cm 2 Less than or equal to, or 3.0 Ω·cm 2 or less.

[0045] The anion exchange membrane can be used in electrodialysis, bipolar membrane electrodialysis, electrodeionization, capacitive deionization, and water electrolysis systems. The anion exchange membrane can have excellent concentration and desalination performance.

[0046] A method for manufacturing an anion exchange membrane according to another embodiment includes providing a porous polymer support comprising a membrane structure, manufacturing a composition for forming an anion exchange polymer comprising a crosslinkable monomer represented by the following Chemical Formula 1, a photoinitiator, and a solvent, impregnating the porous polymer support with the composition for forming an anion exchange polymer to fill the surface and the inside of the pores of the porous polymer support with the composition, laminating a polyester film on at least one surface of the porous polymer support filled with the composition to produce a laminate in which the polyester film and the porous polymer support are laminated together, irradiating the laminate with light to cause a crosslinking reaction of the composition to form an anion exchange polymer, which is a crosslinked product of the composition, on the surface and the inside of the pores of the porous polymer support, and peeling the polyester film from the porous polymer support having the anion exchange polymer formed on the surface and the inside of the pores to produce an anion exchange membrane:

[0047]

Chemical Formula

[0048] In Chemical Formula 1, X - is F - , Cl -, Br - or I - is / are.

[0049] The method for manufacturing the anion exchange membrane can provide an anion exchange membrane having a low sheet resistance, a high ion exchange capacity, and excellent chemical resistance in the presence of high-concentration acids and alkalis.

[0050] FIG. 4 is a schematic flowchart relating to a method for manufacturing an anion exchange membrane according to an embodiment.

[0051] Referring to FIG. 4, first, a porous polymer support comprising a membrane structure is provided (step S1).

[0052] The porosity of the membrane structure is 30% to 80%. For example, the porosity of the membrane structure is 35% to 70%, or 40% to 65%, or 45% to 60%, or 45% to 55%. If the pore size and / or porosity of the membrane structure is less than 30%, it is difficult to improve the physical durability and mechanical strength of the anion exchange membrane to be obtained as a porous polymer support. If the pore size and / or porosity of the membrane structure exceeds 80%, the fraction occupied by the porous polymer support in the anion exchange membrane becomes excessive, the sheet resistance increases, and the ion exchange capacity may decrease.

[0053] The membrane structure contains one or more polymers selected from polyethylene, polypropylene, polyethylene terephthalate, polyvinyl alcohol, polybenzimidazole, polyarylene sulfide, polyether ether ketone, polyether sulfone, polysulfone, polystyrene, polyarylene ether sulfone, and polyether ketone. For example, the membrane structure is polyethylene or polypropylene. For example, the membrane structure is polypropylene.

[0054] The thickness of the porous polymer support is 10 μm to 110 μm. For example, the thickness of the porous polymer support is 20 μm to 110 μm, 40 μm to 110 μm, or 60 μm to 110 μm. Within the thickness range of the porous polymer support, the sheet resistance can decrease and the ion exchange capacity can increase.

[0055] Since the membrane structure has hydrophobic properties, sufficient wettability with the anion exchange polymer cannot be ensured, and thus the desired membrane performance cannot be achieved.

[0056] To complement this, before impregnating the porous polymer support with the composition for forming the anion exchange polymer, the porous polymer support may be further immersed in a surfactant solution, dried, and a porous polymer support having a hydrophilic surface may be produced. The surfactant can be used without limitation as long as it is a material for hydrophilizing in the technical field. For example, one or more materials selected from dodecylbenzenesulfonic acid (DBSA), alkylbenzenesulfonic acid (ABS), linear alkylbenzenesulfonic acid (LAS), alpha-sulfonic acid (AS), alpha-olefin sulfonic acid (AOS), alcohol polyoxyethylene ether (AE), and alcohol polyoxyethylene ether sulfonic acid (AES) can be used. For example, the surfactant can be dodecylbenzenesulfonic acid. If the hydrophobic part of the surfactant is bonded to the surface of the porous polymer support, which is hydrophobic, by hydrophobic-hydrophobic interaction, the hydrophilic part of the surfactant will replace the surface of the porous polymer support, and hydrophilization can be achieved. At this time, not only the surface of the porous polymer support but also the entire surface of the internal pores can be hydrophilized by the surfactant. However, it can be omitted when the degree of hydrophilization of the porous polymer support is sufficient or when the pores of the porous polymer support are sufficiently large and the composition for forming the anion exchange polymer can be filled.

[0057] The surfactant solution contains 0.001% to 6% by weight of a surfactant and the balance of a solvent. For example, the surfactant solution contains 0.01% to 4% by weight and the balance of a solvent, or 0.05% to 3% by weight and the balance of a solvent. If the content of the surfactant in the surfactant solution is less than 0.001% by weight, the surface of the porous polymer support is not hydrophilized, and the composition for forming an anion exchange polymer is not filled into the pores of the porous polymer support. If the content of the surfactant in the surfactant solution exceeds 6% by weight, the surfactant may be eluted or the filling amount of the composition for forming an anion exchange polymer may decrease.

[0058] The immersion is carried out for 0.1 minute to 10 minutes, for example, 0.5 minute to 5 minutes. If the immersion time is less than 0.1 minute, the surface of the porous polymer support is not sufficiently hydrophilized, and the composition for forming an anion exchange polymer is not filled into the pores of the porous polymer support. If the immersion time exceeds 10 minutes, the production rate may decrease and the production cost may increase. The drying is carried out at a temperature of 40°C to 90°C for 1 minute to 20 minutes. For example, the drying is carried out at a temperature of 40°C to 80°C for 1 minute to 10 minutes.

[0059] Next, a composition for forming an anion exchange polymer containing the crosslinkable monomer represented by Chemical Formula 1, a photoinitiator, and a solvent is produced (Step S2).

[0060] The crosslinkable monomer represented by the chemical formula 1 is a monomer in which two vinylbenzyl chlorides are crosslinked to a bi-functional cyclic diamine containing pendant chains to which a quaternary ammonium cation group is attached. The crosslinkable monomer represented by the chemical formula 1 forms a rigid cage structure and can have an improved ion exchange capacity while having chemical stability even under conditions of high concentrations of acid or alkali. Therefore, an anion exchange membrane containing such an anion exchange polymer can have excellent concentration and desalination performance. The "crosslinked product" means a product that includes any of an initial reaction product, an intermediate reaction product, and a final reaction product, in addition to a cured product of a composition containing the crosslinkable monomer represented by the chemical formula 1. The content of the crosslinkable monomer represented by the chemical formula 1 is 30% by weight to 70% by weight based on 100% by weight of the entire composition for forming the anion exchange polymer.

[0061] The photoinitiator is 0.01% by weight to 2% by weight or 0.1% by weight to 1% by weight based on 100% by weight of the entire composition for forming the anion exchange polymer. The photoinitiator can be used without limitation as long as it is a photoinitiator that can be used in the relevant technical field. For example, it is 2-hydroxy-2-methylpropiophenone. The solvent can be used without limitation as long as it is a solvent that can be used in the relevant technical field. For example, it is a water-soluble solvent such as water, methanol, or ethanol, and it is distilled water. The solvent is included in the composition for forming the anion exchange polymer in the remaining amount excluding the crosslinkable monomer represented by the chemical formula 1 and the photoinitiator.

[0062] Next, the porous polymer support is impregnated with the composition for forming an anion exchange polymer, and the composition is filled in the surface and the pores of the porous polymer support (step S3). The impregnation is carried out for 0.1 minute to 10 minutes, for example, 0.5 minute to 5 minutes. If the impregnation is carried out for less than 0.1 minute, the composition for forming an anion exchange polymer is not sufficiently filled in the pores of the porous polymer support, and the performance of the anion exchange membrane may deteriorate or leakage may occur. If the impregnation is carried out for more than 10 minutes, the production rate may decrease and the production cost may increase. Through the impregnation, the composition for forming an anion exchange polymer is filled in the pores of the porous polymer support, and the composition for forming an anion exchange polymer can cover the outer surface of the porous polymer support.

[0063] Next, a polyester film is pressure-bonded to at least one surface of the porous polymer support filled with the composition to produce a laminate in which the polyester film and the porous polymer support are laminated together (step S4).

[0064] The polyester film can be pressure-bonded to the upper surface and / or the lower surface of the porous polymer support via roll calendering. The polyester film is, for example, a polyethylene terephthalate film. The thickness of the polyester film is 10 μm to 150 μm, for example, 20 μm to 120 μm, or 30 μm to 100 μm. If the thickness of the polyester film is less than 10 μm, when laminating with the porous polymer support filled with the anion exchange polymer, poor lamination such as wrinkles in the film may occur. If the thickness of the polyester film exceeds 150 μm, during the crosslinking reaction described later, the thickness of the polyester film is excessively thick, light is not sufficiently irradiated to the porous polymer support, and the crosslinking reaction does not occur sufficiently. One surface of the polyester film that contacts the porous polymer support is untreated or release-treated. By using such a film, the bonding with the porous polymer support having a hydrophilic surface can be hindered, and the anion exchange polymer can be prevented from being removed from the support surface. The pressure bonding is performed at a temperature of 10°C to 35°C, for example, 15°C to 30°C, and a pressure of about 0 bar to 5 bar. The pressure can be appropriately adjusted in consideration of the thickness of the porous polymer support and the thickness of the polyester film.

[0065] Next, the laminate is irradiated with light to cause a crosslinking reaction of the composition, and an anion exchange polymer, which is a crosslinked product of the composition, is formed on the surface and inside the pores of the porous polymer support (step S5).

[0066] The light is ultraviolet light, and for example, UVA, UVB, UVC, and / or UVV can be used. For example, the light irradiation is performed using UVC as ultraviolet light at a light amount of 2000 mJ / cm 2 ~10000 mJ / cm 2 For example, it is performed at a light amount of 2000 mJ / cm 2 ~8000 mJ / cm 2It is carried out with the light quantity. If the amount of ultraviolet rays irradiated is less than the above range and the irradiation time, the crosslinking reaction of the composition for forming the anion exchange polymer does not proceed smoothly. If the amount of ultraviolet rays irradiated exceeds the above range and the irradiation time, the energy is excessively strong, and the porous polymer support and the polyester film may be melted or carbonized.

[0067] Finally, the polyester film is peeled off from the porous polymer support on which the anion exchange polymer is formed on the surface and inside the pores to produce an anion exchange membrane (step S6). The peeling can be performed by pulling out the polyester film attached to the porous polymer support in the opposite direction using a desorption roll.

Example

[0068] Hereinafter, the present invention will be described in more detail through examples. These examples are for more specifically explaining the present invention, and the scope of the present invention is not limited by these examples.

[0069] Example 1: Production of Anion Exchange Membrane A polypropylene porous polymer support with a thickness of 60 μm (porosity: 55%) was prepared.

[0070] Separately, a solution of 4-vinylbenzyl chloride dissolved in methanol was added to a solution of 1,4-diazabicyclo[2,2,2]octane dissolved in methanol so that the molar ratio of vinylbenzyl chloride to 1,4-diazabicyclo[2,2,2]octane was 2:1, and the mixture was stirred at room temperature under an inert atmosphere to produce a mixture. The mixture was filtered, washed with methanol, and then dried under vacuum at room temperature to obtain a crosslinkable monomer represented by the following Chemical Formula 1.

[0071] 66% by weight of the crosslinkable monomer represented by Chemical Formula 1, 0.6% by weight of a 2-hydroxy-2-methylpropiophenone (manufactured by Ciba) photoinitiator, and the balance of distilled water were mixed to produce a composition for forming an anion exchange polymer with a total of 100% by weight.

[0072] The polypropylene porous polymer support was impregnated with the composition for forming the anion exchange polymer, and the composition was filled on the surface and inside the pores of the porous polymer support. The porous polymer support filled with the composition was put into a pressure roll, and a polyester film with a thickness of 50 μm was pressure-bonded to the upper and lower surfaces of the porous polymer support at room temperature to produce a laminate in which the polyester film and the porous polymer support were laminated. Using UVC as ultraviolet light, the laminate was irradiated with a light quantity of 3000 mJ / cm 2 to form an anion exchange polymer, which is a cross-linked product of the composition, on the surface and inside the pores of the porous polymer support. The polyester film was peeled off from the porous polymer support on which the anion exchange polymer was formed on the surface and inside the pores to produce an anion exchange membrane.

[0073]

Chemical formula

[0074] In Chemical formula 1, X - is Cl - and that's it.

[0075] Example 2: Production of Anion Exchange Membrane An anion exchange membrane was produced in the same manner as in Example 1, except that a polypropylene porous polymer support with a thickness of 80 μm (porosity: 45%) was used.

[0076] Example 3: Production of Anion Exchange Membrane An anion exchange membrane was produced in the same manner as in Example 1, except that a polypropylene porous polymer support with a thickness of 110 μm (porosity: 48%) was used.

[0077] Comparative Example 1: Production of Anion Exchange Membrane An anion exchange membrane was produced in the same manner as in Example 1, except that a polypropylene porous polymer support with a thickness of 120 μm (porosity: 28%) was used.

[0078] Comparative Example 2: Production of Anion Exchange Membrane An anion exchange membrane was produced in the same manner as in Example 1, except that a cellulose acetate nonwoven fabric type support with a thickness of 60 μm (porosity: 75%) was used.

[0079] Comparative Example 3: Production of Anion Exchange Membrane An anion exchange membrane was produced in the same manner as in Example 1, except that a polyethylene / polypropylene mesh type support with a thickness of 20 μm (porosity: 84%) was used.

[0080] Comparative Example 4: Production of Anion Exchange Membrane An anion exchange membrane was produced in the same manner as in Example 1, except that a polyethylene porous polymer support with a thickness of 8 μm (porosity: 44%) was used.

[0081] Comparative Example 5: Production of Anion Exchange Membrane An anion exchange membrane was produced in the same manner as in Example 1, except that a composition for forming an anion exchange polymer containing 42% by weight of (3-acrylamidopropyl)trimethylammonium chloride (manufactured by TCI), 14% by weight of N,N'-methylenebisacrylamide (manufactured by Merck), 0.6% by weight of a photoinitiator 2-hydroxy-2-methylpropiophenone (manufactured by Ciba), and the balance of distilled water was used.

[0082] Analysis Example 1: Scanning Electron Microscope (SEM) Photograph The structure of the porous polymer support of the anion exchange membrane produced according to Example 1 was observed at a magnification of x30K using a scanning electron microscope (SEM). The scanning electron microscope used was the S-5500 manufactured by Hitachi. The results are shown in Figure 3.

[0083] Referring to Figure 3, it can be confirmed that the porous polymer support of the anion exchange membrane produced according to Example 1 has a three-dimensional network structure.

[0084] Evaluation Example 1: Physical Property Evaluation The physical properties of each anion exchange membrane produced in Examples 1 to 3 and Comparative Examples 1 to 5 were evaluated as follows. The results are shown in Table 1 below.

[0085] (1) Sheet resistance (Ω·cm 2 ) Each anion exchange membrane was cut into a size of 5 cm × 5 cm to prepare samples. The samples were immersed in a 0.5 M NaCl aqueous solution for 24 hours. The samples were placed between the electrodes for measuring sheet resistance, and the wire resistance (R1) of the anion exchange membrane and the resistance (R2) of the 0.5 M NaCl aqueous solution were measured using an LCR meter (E4908A, manufactured by Agilent). The measured resistance values (R1, R2) were substituted into the following Equation 1 to obtain the sheet resistance (Rm). The results are shown in Table 1.

[0086] [Equation 1] Rm (Ω·cm 2 ) = (R1 - R2) × S In Equation 1, Rm is the sheet resistance of the anion exchange membrane, R1 is the wire resistance of the anion exchange membrane, R2 is the resistance of the 0.5 M NaCl aqueous solution, S is the area of the electrode.

[0087] (2) Ion Exchange Capacity (IEC, meq / g) Each anion exchange membrane was cut into a size of 5 cm × 5 cm to prepare samples. After washing the samples with distilled water, the excess moisture was removed with tissue paper. After filling 70 ml of 1M NaCl solution into a vial, the samples with the removed moisture were placed in the 1M NaCl solution and immersed for 12 hours or more to perform primary pretreatment. Next, the samples after the primary pretreatment were washed several times with distilled water, and the excess moisture was removed with tissue paper. After filling 70 ml of 0.5M Na2CO3 solution into a vial, the samples with the removed moisture were placed in the 0.5M Na2CO3 solution and immersed for 12 hours or more to perform secondary pretreatment. Then, the samples after the secondary pretreatment were taken out from the vial, and the remaining solution was titrated with 0.01M AgNO3 solution, and the volume of the AgNO3 solution added during titration was recorded. After washing the samples several times with distilled water, they were dried in a hot air oven at 80 °C for 15 minutes. After drying was completed, the weight of the dried anion exchange membrane was measured. The measured weight of the dried anion exchange membrane was substituted into the following formula 2 to obtain the ion exchange capacity (IEC). The results are shown in Table 1.

[0088] [Formula 2] IEC (meq / g) = (volume of titrant (ml) × 0.01) / weight of dried anion exchange membrane (g)

[0089] (3) Chemical resistance The anion exchange membranes produced in Example 1 and Comparative Example 5 were cut into a size of 5 cm × 5 cm to prepare samples. After immersing the samples in 1M aqueous solution of NaOH and 0.5M aqueous solution of H2SO4 respectively, the sheet resistance of each was determined in the same manner as in the above “(1) Sheet resistance (Ω·cm 2 )” according to the immersion time (days). The results are shown in Tables 2 and 3.

[0090]

Table 1

[0091] Referring to Table 1, the porous polymer supports of the anion exchange membranes produced according to Examples 1 to 3 are polypropylene membranes with a porosity of 48% to 55% and a thickness of 60 μm to 110 μm. The porous polymer support of the anion exchange membrane produced according to Comparative Example 1 is a polypropylene membrane with a porosity of 28% and a thickness of 120 μm. The anion exchange membranes produced according to Examples 1 to 3 have a sheet resistance of 9.6 Ω·cm 2 or less, and the ion exchange capacity (IEC) is improved to 1.8 meq / g or more.

[0092] In addition, the porous polymer support of the anion exchange membrane produced according to Comparative Example 2 is a cellulose acetate non-woven fabric type support with a thickness of 60 μm and a porosity of 75%. The anion exchange membrane produced according to Comparative Example 2 was applied to an electrodialysis system using a 15 wt% NaCl aqueous solution as raw water for concentration, but concentration could not be achieved.

[0093] The porous polymer support of the anion exchange membrane produced according to Comparative Example 3 is a polyethylene / polypropylene porous polymer support with a thickness of 20 μm and a porosity of 84%. The anion exchange membrane produced according to Comparative Example 3 was applied to an electrodialysis system using a 15 wt% NaCl aqueous solution as raw water for concentration, but concentration could not be achieved.

[0094] The porous polymer support of the anion exchange membrane produced according to Comparative Example 4 is a polyethylene porous polymer support with a thickness of 8 μm and a porosity of 44%. The anion exchange membrane produced according to Comparative Example 4 was too thin in thickness and could not be assembled into a module.

[0095]

Table 2

[0096]

Table 3

[0097] Table 2 shows the results of immersing the anion exchange membrane produced in Example 1 and Table 3 shows the results of immersing the anion exchange membrane produced in Comparative Example 5 in 1M aqueous NaOH solution and 0.5M aqueous H2SO4 solution respectively, and measuring the sheet resistance according to the immersion time. Referring to Table 2, the anion exchange membrane produced in Example 1 was immersed in 1M aqueous NaOH solution and 0.5M aqueous H2SO4 solution respectively, and the change in sheet resistance after 40 days was about 6.7% and about 3% respectively. Referring to Table 3, the anion exchange membrane produced in Comparative Example 5 was immersed in 1M aqueous NaOH solution and 0.5M aqueous H2SO4 solution respectively, and the change in sheet resistance after 40 days was about 41% and about 11% respectively.

[0098] Therefore, it can be confirmed that the anion exchange membrane produced in Example 1 has less change in sheet resistance after 40 days and is excellent in chemical resistance when immersed in 1M aqueous NaOH solution and 0.5M aqueous H2SO4 solution respectively, compared with the anion exchange membrane produced in Comparative Example 5.

[0099] From this, it can be seen that the anion exchange membranes produced according to Examples 1 to 3 are suitable for use in electrodialysis, bipolar membrane electrodialysis, electrodeionization, capacitive deionization, or water electrolysis systems.

Claims

1. A porous polymer support comprising a membrane structure, and an anion exchange polymer, wherein the anion exchange polymer is located on the surface and inside the pores of the porous polymer support, the anion exchange groups of the anion exchange polymer are uniformly distributed on the surface and inside the pores of the porous polymer support, the anion exchange polymer is a cross-linked product of a composition containing a cross-linkable monomer represented by the following Chemical Formula 1: Anion exchange membrane 【Chemical 1】 In Chemical Formula 1, X － is F － , Cl － , Br － , or I － .

2. The anion exchange membrane according to Claim 1, wherein the membrane structure has a structure in which pores are regularly arranged or a three-dimensional network structure.

3. The anion exchange membrane according to Claim 1, wherein the porosity of the membrane structure is 30% to 80%.

4. The anion exchange membrane according to Claim 1, wherein the membrane structure contains one or more polymers selected from polyethylene, polypropylene, polyethylene terephthalate, polyvinyl alcohol, polybenzimidazole, polyarylene sulfide, polyether ether ketone, polyether sulfone, polysulfone, polystyrene, polyarylene ether sulfone, and polyether ketone.

5. The anion exchange membrane according to Claim 1, wherein the thickness of the porous polymer support is 10 μm to 110 μm.

6. The anion exchange membrane according to Claim 1, wherein the average thickness of the anion exchange membrane is 10 μm to 200 μm.

7. The anion exchange membrane according to Claim 1, wherein the ion exchange capacity of the anion exchange membrane is 1.5 meq / g or more.

8. The sheet resistance of the anion exchange membrane is 10 Ω·cm ２ The anion exchange membrane according to claim 1, wherein the following holds.

9. The anion exchange membrane according to Claim 1, wherein the anion exchange membrane is used in electrodialysis, bipolar membrane electrodialysis, electrodeionization, capacitive deionization, or a water electrolysis system.

10. Providing a porous polymer support comprising a membrane structure, Manufacturing a composition for forming an anion exchange polymer containing a cross-linkable monomer represented by the following Chemical Formula 1, a photoinitiator, and a solvent, Impregnating the porous polymer support with the composition for forming the anion exchange polymer, and filling the composition into the surface and the pores of the porous polymer support; Pressing a polyester film onto at least one surface of the porous polymer support filled with the composition to produce a laminate in which the polyester film and the porous polymer support are laminated; Irradiating the laminate with light to cause a cross-linking reaction of the composition, and forming an anion exchange polymer, which is a cross-linked product of the composition, on the surface and in the pores of the porous polymer support; Peeling the polyester film from the porous polymer support having the anion exchange polymer formed on the surface and in the pores to produce an anion exchange membrane. A method for producing an anion exchange membrane, comprising: 【Chemical Formula 2】 In Chemical Formula 1, X － is F － , Cl － , Br － , or I － .

11. The method for producing an anion exchange membrane according to claim 10, wherein the content of the crosslinkable monomer represented by Chemical Formula 1 is 30% by weight to 70% by weight based on 100% by weight of the entire composition for forming the anion exchange polymer.

12. The method for producing an anion exchange membrane according to claim 10, wherein the porosity of the membrane structure is 30% to 80%.

13. The method for producing an anion exchange membrane according to claim 10, wherein the membrane structure contains one or more polymers selected from polyethylene, polypropylene, polyethylene terephthalate, polyvinyl alcohol, polybenzimidazole, polyarylene sulfide, polyether ether ketone, polyether sulfone, polysulfone, polystyrene, polyarylene ether sulfone, and polyether ketone.

14. The method for producing an anion exchange membrane according to claim 10, wherein the thickness of the porous polymer support is 10 μm to 110 μm.

15. The method for producing an anion exchange membrane according to claim 10, further comprising, before impregnating the porous polymer support with the composition for forming the anion exchange polymer, immersing the porous polymer support in a surfactant solution, drying it, and producing a porous polymer support having a hydrophilic surface.

16. The irradiation of the light is performed using UVC as ultraviolet light with a light quantity of 2000 mJ / cm ２ to 10000 mJ / cm ２ for the method for producing an anion exchange membrane according to claim 10.

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