KR102166203B1 - Polyvalent ion excluding type ion exchange membrane - Google Patents

Abstract

Disclosed are a polyvalent ion exclusion type ion exchange membrane and a method of manufacturing the ion exchange membrane. The polyvalent ion exclusion type ion exchange membrane has a high content ratio of an anion exchange polymer electrolyte in the surface portion, a high content ratio of cation exchange polymer electrolyte in the center portion, and a cation exchange polymer electrolyte for an anion exchange polymer electrolyte from the surface to the center in the thickness direction. By having a structure in which the content ratio of is continuously increased, the permeation of the multivalent cation to the exchange membrane is significantly reduced compared to the monovalent cation, thereby having high selectivity to the monovalent cation.

Description

Polyvalent ion exclusion type ion exchange membrane {POLYVALENT ION EXCLUDING TYPE ION EXCHANGE MEMBRANE}

The present invention relates to a polyvalent ion exclusion type ion exchange membrane and a method of manufacturing the same.

The development of a new energy source that can replace this is required due to concerns such as depletion of fossil fuels such as petroleum and coal and global warming due to the generation of carbon dioxide generated by the use of fossil fuels. In this regard, various renewable energy sources, such as solar heat, biofuel, geothermal heat, and wind power, are currently being developed and researched around the world, but these new and renewable energy sources still remain at less than 10% of the world's energy consumption. Moreover, solar and wind, which are being studied as promising alternative energy sources for fossil fuels, have disadvantages in terms of securing stable energy production because the energy production is very sensitive to the surrounding climatic environment, and there is no fear of exhaustion. Of course, interest in eco-friendly alternative energy sources that can stably generate energy is increasing.

Meanwhile, as the eco-friendly alternative energy source, a monovalent cation-selective ion exchange membrane is required for the process of producing high-purity salt using the electrodialysis process, the process of producing high-purity caustic soda, and the process of producing soft water. There is an urgent need to develop a highly monovalent cation-selective ion exchange membrane for recovery of fermentation processes in which monovalent ion selectivity is required in the ion process, food industry, pharmaceutical chemicals, acid and heavy metal recovery, and wastewater neutralization. Accordingly, research on a monovalent cation-selective ion exchange membrane is actively progressing due to the above necessity, but the development of an ion exchange membrane that selectively permeates only monovalent cations compared to polyvalent cations at a high ratio is still insufficient.

Accordingly, the inventors of the present invention formed an ion exchange membrane by forming a cation exchange polymer electrolyte in the center of the porous polymer support and forming an anion exchange polymer electrolyte on the surface of the porous polymer support while researching the monovalent cation-selective ion exchange membrane. The present invention was completed by finding that the valent cations selectively permeate the ion exchange membrane at a high rate.

In this regard, Korean Patent Registration No. 10-1511990 discloses an ion exchange membrane for a reverse electrodialysis apparatus and a reverse electrodialysis apparatus including the same.

The present invention has been devised to solve the above-described problem, and an embodiment of the present invention provides a polyvalent ion exclusion type ion exchange membrane.

In addition, another embodiment of the present invention provides a method of manufacturing a polyvalent ion exclusion type ion exchange membrane.

The technical problem to be achieved by the present invention is not limited to the technical problems mentioned above, and other technical problems that are not mentioned can be clearly understood by those of ordinary skill in the technical field to which the present invention belongs from the following description. There will be.

As a technical means for achieving the above technical problem, one aspect of the present invention,

A polymeric support having a porous structure; And an ion exchange polymer electrolyte impregnated in the polymer support, wherein the ion exchange polymer electrolyte includes a cation exchange polymer electrolyte and an anion exchange polymer electrolyte, and a cation exchange polymer in the center of the polymer support An electrolyte is impregnated, and an anion exchange polymer electrolyte is impregnated on a surface portion of the polymer support.

The content ratio of the cation-exchange polymer electrolyte and the anion-exchange polymer electrolyte may have a relationship of Formula 1 below.

[Equation 1]

A ≥ B

In Equation 1, A is the content ratio of the cation exchange polymer electrolyte to the anion exchange polymer electrolyte at the center of the polymer support, and B is the content ratio of the cation exchange polymer electrolyte to the anion exchange polymer electrolyte at the surface part of the polymer support. And, the central portion is an area from a surface to a depth of 20% to 80% in a center direction with respect to 100% of the thickness of the polymer support, and the surface portion is 0 in a center direction from the surface to 100% of the thickness of the polymer support. % To 20% depth.

The content ratio of the cation exchange polymer electrolyte to the anion exchange polymer electrolyte may increase from the surface to the center according to the thickness direction of the polymer support.

The content of the anion exchange polymer electrolyte may be 10% to 40% of the content of the cation exchange polymer electrolyte.

The cation exchange polymer electrolyte may be crosslinked polymerization of an electrolyte monomer containing sulfonic acid having an anionic group.

The sulfonic acid-containing electrolyte monomer having an anionic group is 2-acrylamide-2-methylpropanesulfonate sodium, vinylsulfonate sodium, vinylsulfonic acid, Allyl sulfonate sodium, 2-methyl-2-propene-1-sulfonate sodium, 3-sulfopropyl acrylate sodium acrylate sodium) and combinations thereof may include a material selected from the group consisting of.

The anion exchange polymer electrolyte may be obtained by crosslinking polymerization of an electrolyte monomer of a quaternary ammonium salt having a cationic group.

Electrolytic monomers of the quaternary ammonium salt having a cationic group are (3-acrylamidopropyl) trimethylammonium chloride [(3-acrylamidopropyl) trimethylammonium chloride], (vinylbenzyl) trimethylammonium chloride [(vinylbenzyl)trimethylammonium chloride] and combinations thereof It may include a material selected from the group consisting of.

The porous polymer support may have a pore volume of 40% to 50%, a pore size of 0.07 μm to 0.1 μm, and a thickness of 8 μm to 30 μm.

The thickness ratio of the polyvalent ion exclusion type ion exchange membrane to the thickness of the polymer support may be 1.0 to 1.03.

In addition, another aspect of the present invention,

Impregnating a porous polymer support in a cation exchange precursor solution containing an electrolyte monomer having an anionic group, a crosslinking agent, an initiator, and a solvent; Irradiating light to the porous polymer support to crosslink the cation exchange precursor solution to form a cation exchange polymer electrolyte in the center of the porous polymer support; Impregnating an anion exchange precursor solution comprising an electrolyte monomer having a cationic group, a crosslinking agent, an initiator, and a solvent with a porous polymer support having the cation exchange polymer electrolyte formed therein; And forming an anion exchange polymer electrolyte on the surface of the porous polymer support by irradiating light to the porous polymer support impregnated with the anion exchange precursor solution to crosslink the anion exchange precursor solution to form an anion exchange polymer electrolyte on the surface of the porous polymer support. It provides a method of manufacturing an exchange membrane.

The electrolyte monomer having an anionic group may be a sulfonic acid-containing electrolyte monomer.

The electrolyte monomer having the cationic group may be a tetravalent ammonium salt electrolyte monomer.

The porous polymer support may be hydrophilized by a surfactant before being impregnated with the cation exchange precursor solution.

In the method of manufacturing the polyvalent ion exclusion type ion exchange membrane, before the step of forming the cation exchange polymer electrolyte, an upper film, a porous polymer support impregnated with the cation exchange precursor solution, and a lower film are added to a pressing roll to form the upper and lower layers of the polymer support. Compressing the upper film and the lower film to the lower part, respectively; And desorbing the polymer support, the upper film, and the lower film including the formed cation exchange polymer electrolyte from a desorption roll after the step of forming the cation exchange polymer electrolyte.

In the method of manufacturing the polyvalent ion exclusion type ion exchange membrane, before the step of forming the anion exchange polymer electrolyte, an upper film, a porous polymer support impregnated with the anion exchange precursor solution, and a lower film are added to a pressing roll to form the upper and lower layers of the polymer support. Compressing the upper film and the lower film to the lower part, respectively; And desorbing the polymer support, the upper film, and the lower film including the formed anion exchange polymer electrolyte from the desorption roll after the step of forming the anion exchange polymer electrolyte.

The upper film and the lower film may have one surface in contact with the porous polymer support having a hydrophilic treatment.

The compression is performed through squeeze compression, and the sum of the thickness of the porous polymer support and the film thickness introduced into the pressing roll through the squeeze compression may have a value of 70% to 97% compared to the total thickness before the injection.

The crosslinked polymerized polymer resin formed on the outside of the porous polymer support may be transferred to and removed from the upper film and the lower film through the desorption.

According to an embodiment of the present invention, the polyvalent ion exclusion type ion exchange membrane has a high content ratio of an anion exchange polymer electrolyte in the surface portion, a high content ratio of cation exchange polymer electrolyte in the center portion, and anion exchange from the surface toward the center in the thickness direction. By having a structure in which the content ratio of the cation exchange polymer electrolyte to the polymer electrolyte continuously increases, the permeation of the multivalent cation to the exchange membrane is significantly reduced compared to the monovalent cation, thereby having high selectivity to the monovalent cation.

The effects of the present invention are not limited to the above effects, and should be understood to include all effects that can be inferred from the configuration of the invention described in the detailed description or claims of the present invention.

1 is a schematic diagram showing a polyvalent ion exclusion type ion exchange membrane according to an embodiment of the present invention.
2 is a schematic diagram showing a method of manufacturing a polyvalent ion exclusion type ion exchange membrane according to an embodiment of the present invention.
3 is a schematic diagram showing a roll-to-roll manufacturing process of a polyvalent ion exclusion type exchange membrane according to an embodiment of the present invention.
4 is a schematic diagram of an apparatus for measuring conductivity in a solution in order to calculate the membrane permeability of an ion exclusion type exchange membrane according to an embodiment and a comparative example of the present invention.
5A to 5C show the concentration of the concentration calculated from the conductivity measured by the apparatus of FIG. 4 for the multivalent ion exclusion type ion exchange membrane according to the Examples and Comparative Examples of the present application using NaCl aqueous solution, MgCl ₂ aqueous solution, and CaCl ₂ aqueous solution, respectively. It is a graph showing the change according to the result, and FIG. 5D is a graph integrating the results shown in FIGS. 5A to 5C.

Hereinafter, the present invention will be described in more detail. However, the present invention may be implemented in various different forms, and the present invention is not limited by the embodiments described herein, and the present invention is only defined by the claims to be described later.

In addition, terms used in the present invention are used only to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In the entire specification of the present invention, "including" a certain component means that other components may be further included rather than excluding other components unless otherwise specified.

The first aspect of the present application,

A polymeric support having a porous structure; And an ion exchange polymer electrolyte impregnated in the polymer support, wherein the ion exchange polymer electrolyte includes a cation exchange polymer electrolyte and an anion exchange polymer electrolyte, and a cation exchange polymer in the center of the polymer support An electrolyte is impregnated, and an anion exchange polymer electrolyte is impregnated on a surface portion of the polymer support.

Hereinafter, a polyvalent ion exclusion type ion exchange membrane according to the first aspect of the present application will be described in detail with reference to FIG. 1.

In one embodiment of the present application, Figure 1 is a schematic diagram showing a polyvalent ion exclusion type ion exchange membrane 1, first, in the present specification, the cation exchange polymer electrolyte 120 impregnated in the center of the polymer support 110 is impregnated only in the center It should be interpreted to mean that the anion exchange polymer electrolyte 130 impregnated on the surface of the polymer support 110 is also partially impregnated not only in the surface portion but also in the center portion. do.

In one embodiment of the present application, the polyvalent ion exclusion type ion exchange membrane (1) is impregnated with an anion exchange polymer electrolyte (130) having a cationic group on the surface of the polymer support (110), so that the amount of charge relative to the monovalent cations In the case of this large polyvalent cation, the anion exchange polymer electrolyte 130 may be relatively impermeable to the anion exchange polymer electrolyte 130 compared to the monovalent cation due to a strong repulsion force with the cationic group of the anion exchange polymer electrolyte 130 impregnated on the surface. . On the other hand, the monovalent cation having a relatively small amount of charge has a weaker repulsive force with the anion exchange polymer electrolyte 130 having a cation group compared to the polyvalent cation, so that it can relatively easily penetrate the anion exchange polymer electrolyte 130, and the polymer support ( 110) Since the cation exchange polymer electrolyte 120 impregnated in the center can be reached, the multivalent ion exclusion type ion exchange membrane 1 may be capable of selectively permeating only monovalent cations.

In one embodiment of the present application, the content ratio of the cation exchange polymer electrolyte 120 and the anion exchange polymer electrolyte 130 may have a relationship of Equation 1 below.

[Equation 1]

A ≥ B

In Equation 1, A is the content ratio of the cation exchange polymer electrolyte 120 to the anion exchange polymer electrolyte 130 in the center of the polymer support 110, and B is an anion at the surface of the polymer support 110 It is the content ratio of the cation exchange polymer electrolyte 120 to the exchange polymer electrolyte 130, and the central portion is a region from the surface to a depth of 20% to 80% in the center direction with respect to 100% of the thickness of the polymer support 110 The surface portion may be a region ranging from 0% to 20% in a center direction from the surface with respect to 100% of the thickness of the polymer support 110. That is, the content of the cation exchange polymer electrolyte 120 to the anion exchange polymer electrolyte 130 is the same in the region from the surface to a depth of 20% to 80% in the center direction with respect to 100% of the thickness of the polymer support 110 The content of the anion exchange polymer electrolyte 130 to the cation exchange polymer electrolyte 120 may be larger, and in the region from 0% to 20% depth in the center direction from the surface to 100% of the thickness of the polymer support 110 It can be the same or even larger. Accordingly, the distribution of both the cation exchange polymer electrolyte 120 and the anion exchange polymer electrolyte 130 may not be excluded, only the content ratio is different with respect to the entire polymer support 110 (the center portion and the surface portion).

In one embodiment of the present application, the content ratio of the cation exchange polymer electrolyte 120 to the anion exchange polymer electrolyte 130 may increase as the polymer support 110 goes from the surface to the center according to the thickness direction. . The content ratio of the cation exchange polymer electrolyte 120 to the anion exchange polymer electrolyte 130 may continuously increase from the surface to the center according to the thickness direction of the polymer support 110 or may not be a continuous increase. . If it is not a continuous increase, the ratio of the content of the cation exchange polymer electrolyte 120 to the anion exchange polymer electrolyte 130 may increase rapidly at the interface between the surface portion and the center.

In one embodiment of the present application, the content of the anion exchange polymer electrolyte 130 may be 10% to 40% of the content of the cation exchange polymer electrolyte 120. When the content of the anion exchange polymer electrolyte 130 is less than 10%, polyvalent cations can also pass through the polyvalent ion exclusion type ion exchange membrane 1, so that only monovalent cations cannot be selectively permeated. Too many cationic groups in the exchange polymer electrolyte 130 may cause a problem in that monovalent cations are also impermeable.

In one embodiment of the present application, the cation exchange polymer electrolyte 120 may be crosslinked polymerized with a sulfonic acid-containing electrolyte monomer having an anionic group, and the sulfonic acid-containing electrolyte monomer having an anionic group may be represented by Formula 1 below.

[Formula 1]

In Formula 1, R ₁ may be a substituted or unsubstituted linear or branched alkyl or aryl, and A may be hydrogen and a metal element.

In one embodiment of the present application, the electrolytic monomer containing sulfonic acid having an anionic group is 2-acrylamide-2-methylpropanesulfonate sodium, vinylsulfonate sodium, vinyl Sulfonic acid, allyl sulfonate sodium, 2-methyl-2-propene-1-sulfonate sodium, 3-sulfonate It may include a material selected from the group consisting of 3-sulfopropyl acrylate sodium and combinations thereof.

In one embodiment of the present application, the anion exchange polymer electrolyte 130 may be a crosslinked polymerization of an electrolyte monomer of a quaternary ammonium salt having a cationic group, and the electrolyte monomer of the quaternary ammonium salt may be represented by Formula 2 below.

[Formula 2]

In Formula 2, R ₂ to R ₅ may be substituted or unsubstituted linear or branched alkyl or aryl, and B may be a halogen element.

In one embodiment of the present application, the electrolyte monomer of the quaternary ammonium salt having a cationic group is (3-acrylamidopropyl) trimethylammonium chloride [(3-acrylamidopropyl)trimethylammonium chloride], (vinylbenzyl) trimethylammonium chloride [(vinylbenzyl )trimethylammonium chloride] and combinations thereof may include a material selected from the group consisting of.

In one embodiment of the present application, the porous polymer support 110 is not limited if it is a hydrocarbon-based polymer, for example, polyethylene, polypropylene, polyimide, polyamideimide, polypropylene oxide, polyethersulfone, poly It may include a material selected from the group consisting of urethane and combinations thereof, but is not limited thereto.

In one embodiment of the present application, the porous polymer support 110 may have a pore volume of 40% to 50%, a pore size of 0.07 μm to 0.1 μm, and a thickness of 8 μm to 30 μm. If the porous polymer support 110 does not satisfy the above characteristics, the cation and anion exchange polymer electrolytes are not smoothly impregnated into the porous polymer support 110, so that the polyvalent ion exclusion type ion exchange membrane 1 may not be easily manufactured. have.

In one embodiment of the present application, the polyvalent ion exclusion type ion exchange membrane 1 may have no by-products on its surface by removing the polymer resin crosslinked on the outside of the porous polymer support 110, and thus the thickness is thin. Can have This may be that the above characteristics are achieved when the multivalent ion-embedded ion exchange membrane 1 is manufactured according to a roll-to-roll process, and this will be described in detail later in the second aspect of the present application.

In one embodiment of the present application, a ratio of the thickness of the polyvalent ion exclusion type ion exchange membrane 1 to the thickness of the polymer support 110 may be 1.0 to 1.03. Since the cation exchange polymer electrolyte 120 and the anion exchange polymer electrolyte 130 are filled in the polymer support, the thickness of the polyvalent ion exclusion type ion exchange membrane 1 is equal to the thickness of the polymer support 110, or 2 As will be described later, the surface may be slightly thick due to the roughness of the surface caused by the removal of the anionic polymer electrolyte, and when the thickness ratio exceeds 1.03, the anion exchange polymer electrolyte 130 is completely removed from the surface of the ion exchange membrane (1). It may not be, which may act as an impediment to ion exchange. For example, the thickness ratio may be more preferably 1.0 to 1.02.

The second aspect of the present application,

Impregnating a porous polymer support in a cation exchange precursor solution containing an electrolyte monomer having an anionic group, a crosslinking agent, an initiator, and a solvent; Irradiating light to the porous polymer support to crosslink the cation exchange precursor solution to form a cation exchange polymer electrolyte in the center of the porous polymer support; Impregnating an anion exchange precursor solution comprising an electrolyte monomer having a cationic group, a crosslinking agent, an initiator, and a solvent with a porous polymer support having the cation exchange polymer electrolyte formed therein; And forming an anion exchange polymer electrolyte on the surface of the porous polymer support by irradiating light to the porous polymer support impregnated with the anion exchange precursor solution to crosslink the anion exchange precursor solution to form an anion exchange polymer electrolyte on the surface of the porous polymer support. It provides a method of manufacturing an exchange membrane.

Detailed descriptions of portions overlapping with the first aspect of the present application have been omitted, but the description of the first aspect of the present application may be equally applied even if the description is omitted in the second aspect.

Hereinafter, a method of manufacturing the polyvalent ion exclusion type ion exchange membrane according to the second aspect of the present application will be described in detail step by step with reference to FIGS. 2 and 3. 2 is a schematic diagram showing a method of manufacturing a polyvalent ion exclusion type ion exchange membrane according to an embodiment of the present invention, and FIG. 3 is a schematic diagram showing a roll-to-roll manufacturing process of a polyvalent ion exclusion type exchange membrane according to an embodiment of the present invention .

First, in one embodiment of the present application, the method of manufacturing the polyvalent ion exclusion type ion exchange membrane 1 is a porous polymer support in the cation exchange precursor solution 700 including an electrolyte monomer having an anionic group, a crosslinking agent, an initiator, and a solvent ( 110) and impregnating (S100).

In one embodiment of the present application, the electrolyte monomer having an anionic group may be a sulfonic acid-containing electrolyte monomer, for example, 2-acrylamide-2-methylpropanesulfonate sodium. , Vinylsulfonate sodium, vinylsulfonic acid, allyl sulfonate sodium, 2-methyl-2-propene-1-sulfonate sodium (2-methyl-2- Propene-1-sulfonate sodium), 3-sulfopropyl acrylate sodium, and combinations thereof may include a material selected from the group consisting of.

In one embodiment of the present application, the crosslinking agent may be an acrylamide-based crosslinking agent having a tertiary amine functional group, which may be represented by Formula 3 below.

[Formula 3]

In Formula 3, R ₆ and R ₇ may be substituted or unsubstituted linear or branched alkyl or aryl.

In one embodiment of the present application, the acrylamide-based crosslinking agent having a tertiary amine functional group, for example, N,N'-bis(acryloyl)pyrerazine [N,N'bis(acryloyl)piperazine], N ,N'-(1,2-dihydroxyethylene)bisacrylamide [N,N'-(1,2-dihydroxyethylene)bisacrylamide], N,N'-methylenebisacrylamide (N,N'-methylenebisacrylamide) , N,N'-methylenebismethacrylamide (N,N'-methylenebismethacrylamide) and may include a material selected from the group consisting of combinations thereof.

In one embodiment of the present application, the crosslinking agent determines the degree of crosslinking of the polyvalent ion exclusion type ion exchange membrane 1, and the swelling degree and mechanical properties of the ion exchange membrane may be adjusted according to the content.

In one embodiment of the present application, the initiator may be a photoinitiator, and for example, one of the Darocur or Irgacure series manufactured by Ciba Geigy of Switzerland may be used, or 2-hydroxy It may be to use -2-methyl-1-phenylpropane-1-one (2-hydroxy-2-methy-1-phenylpropane-1-one).

In one embodiment of the present application, the solvent may be a water-soluble solvent such as water, methanol or ethanol, and preferably, the solvent may be water.

In one embodiment of the present application, the cation exchange precursor solution 700 contains about 44 parts by weight to about 47 parts by weight of the electrolyte monomer having the anionic group, and about 6 parts by weight to about 12 parts by weight of the crosslinking agent. And the content of the solvent may be mixed in a ratio of about 44 parts by weight to about 47 parts by weight, and the content of the initiator is about 0.1 parts by weight based on 100 parts by weight of a solution in which the electrolyte monomer having an anionic group, a crosslinking agent, and a solvent are mixed. To about 0.5 parts by weight. When the content of the electrolyte monomer having an anionic group is less than the above range, the ion exchange capacity capable of improving the ionic conductivity of the produced ion exchange membrane 1 may be insufficient, and when the content exceeds the above range, the durability of the manufactured ion exchange membrane 1 Can be reduced. In addition, when the content of the crosslinking agent is less than the above range, durability of the produced ion exchange membrane 1 may be reduced due to insufficient crosslinking, and when the content of the crosslinking agent is exceeding the above range, the degree of crosslinking is too high and the ionic conductivity of the produced ion exchange membrane 1 Can be significantly reduced.

In one embodiment of the present application, the porous polymer support 110 may be hydrophilized by a surfactant before being impregnated with the cation exchange precursor solution 700. At this time, the surfactant may be used that can be hydrophilic, for example, dodecylbenzenesulfonic acid (DBSA), alkylbenzenesulfonic acid (ABS), linear alkylbenzenesulfonic acid (linearalklybenzenesulfonic acid, LAS) ), alphasulfonic acid (AS), alphaolefinsulfonic acid (AOS), alcoholpolyoxyethyleneether (AE), alcoholpolyoxyethyleneethersulfonic acid (AES), and combinations thereof A material selected from the group consisting of may be used, and preferably dodecylbenzenesulfonic acid may be used. When the surfactant is bonded to the surface of the polymer support 110 in which the hydrophobic part is hydrophobic through hydrophobic-hydrophobic interaction, the hydrophilic part of the surfactant replaces the surface of the polymer support 110 and thus hydrophilization is achieved. I can. At this time, not only the outer surface of the polymer support 110 but also the entire inner pore surface may be hydrophilized by the surfactant. As the entire pore surface becomes hydrophilic, the hydrophilic cation exchange precursor solution 700 may be effectively and easily filled into the pores by hydrophilic-hydrophilic interaction. Specifically, the hydrophilization treatment is performed by immersing the porous polymer support 110 for 1 to 2 minutes in a solution of 0.5 to 1 part by weight of a commercially available surfactant diluted in water and then drying the pore surface. It may be to hydrophilize.

Next, in one embodiment of the present application, the method of manufacturing the polyvalent ion exclusion type ion exchange membrane 1 is a crosslinking reaction of the cation exchange precursor solution 700 by irradiating light to the porous polymer support 110 And forming a cation exchange polymer electrolyte 120 in the center of the porous polymer support 110 (S200).

In one embodiment of the present application, step S200 may be performed according to the roll-to-roll process shown in FIG. 3. In this case, before step S200, the upper film 200, the porous polymer support 110 and the lower film 300 impregnated in the cation exchange precursor solution 700 are added to a pressing roll to It may further include the step of compressing the upper film 200 and the lower film 300, respectively, to the lower portion, the polymer support 110 including the cation exchange polymer electrolyte formed after step S200, the upper film 200 ) And detaching the lower film 300 from the detachment roll. At this time, the compression roll may include an upper compression roll 400 and a lower compression roll 450 that are vertically spaced apart, that is, two compression rolls may be used, and the detachment roll is also vertically spaced apart. It may include an upper detachable roll 500 and a lower detachable roll 550, that is, it may be to use two detachable rolls. Hereinafter, the case where the step S200 is performed according to the roll-to-roll process will be described in detail, but this step is not limited to the roll-to-roll process.

In one embodiment of the present application, the upper film 200 and the lower film 300 may be poly(ethylene terephthalate) [poly(ethylene terephthalate), PET].

In one embodiment of the present application, the thickness of the upper film 200 and the lower film 300 may be about 30 μm to about 70 μm, preferably about 50 μm to about 60 μm. When the thickness of the upper film 200 and the lower film 300 is less than 30 μm, the porous polymer support 110 and the upper film 200 and the lower film 300 are not smoothly detached after a crosslinking reaction to be described later. The porous polymer support 110 may be torn, and if it exceeds 70 μm, the film is too thick when irradiated with light to be described later, and the light is not sufficiently irradiated to the porous polymer support 110, resulting in a crosslinking reaction. Problems that don't happen enough can arise.

In one embodiment of the present application, one surface of the upper film 200 and the lower film 300 in contact with the porous polymer support 110 may not be water-repellent or may be hydrophilic. The hydrophilic treatment may be, for example, hydrophilic treatment with silicone, polyvinyl alcohol, polyallylamine hydrochloride, polyvinylamine, polystyrene sulfonic acid, polyvinyl sulfonic acid, or the like, and preferably hydrophilic treatment with silicone. That is, by hydrophilizing one surface of the upper film 200 and the lower film 300 in contact with the porous polymer support 110, it is possible to more easily combine with the porous polymer support 110 that has been hydrophilized by a surfactant. It can be what can be.

In one embodiment of the present application, the compression may be performed through squeeze compression so as to have a value lower than the sum of the thickness of the porous polymer support 110 and the thickness of the films 200 and 300 added to the pressing roll. At this time, the squeeze compression is about 50 kg _f /cm ² to about 100 kg _f /cm ² It may be performed under the pressure of. That is, the crosslinked polymerized polymer resin 710 formed outside the porous polymer support 110 as described later by more strongly bonding the porous polymer support 110 and the films 200 and 300 through the squeeze compression is used as the upper film. It can be more easily transferred to the 200 and the lower film 300 and removed.

In one embodiment of the present application, the sum of the thickness of the porous polymer support and the film thickness added to the pressing roll through the squeeze pressing may have a value of 70% to 97% compared to the sum of the thickness before the injection. If the value is less than 70%, a problem may occur in that the porous polymer support 110, the upper film 200, and the lower film 300 may not be easily detached in the subsequent detachment step, and the value is 90%. If it is exceeded, the crosslinked polymerized polymer resin 710 formed on the outside of the porous polymer support 110 in the subsequent desorption step may not be removed due to poor transfer to the upper film 200 and the lower film 300.

In one embodiment of the present application, the speed at which the upper film 200, the porous polymer support 110 and the lower film 300 are introduced into the pressing roll may be about 0.5 M/min to about 2 M/min. If the speed is less than 0.5 M/min, the process proceeds slowly and production efficiency may decrease, and if it exceeds 2 M/min, the process proceeds rapidly, and the crosslinking reaction of the cation exchange precursor solution 700 is smoothly performed in the subsequent process. You can't lose.

In one embodiment of the present application, the crosslinking reaction of the cation exchange precursor solution 700 is performed by irradiating light to the porous polymer support 110 to which the upper film 200 and the lower film 300 are compressed. I can. In this case, the light irradiation may be performed on both the upper and lower portions of the porous polymer support 110 to which the upper film 200 and the lower film 300 are compressed.

In one embodiment of the present application, the irradiated light may be ultraviolet rays, and the types of ultraviolet rays may be classified into UVA, UVB and UVV, and the ultraviolet rays may have different wavelength bands. Specifically, UVA may have a wavelength band of about 320 nm to about 400 nm, UVB of about 280 nm to about 320 nm, and UVV of about 400 nm to about 450 nm.

In one embodiment of the present application, the energy of the irradiated ultraviolet rays is about 40 mW/cm ² to about 50 mW/cm ² for UVA, about 30 mW/cm ² to about 50 mW/cm ^{2 for} UVB, and UVV may be about 30 mW/cm ² to about 50 mW/cm ² , preferably about 47 mW/cm ² for UVA, about 37 mW/cm ^{2 for} UVB and about 35 mW/cm for UVV ^It can be ² . When the energy of the irradiated ultraviolet rays is less than the above range, the crosslinking reaction of the cation exchange precursor solution 700 may not proceed smoothly, and when the energy of the cation exchange precursor solution 700 is exceeded, the energy is too strong and the porous polymer support 110, the upper film ( 200) and the lower film 300 may be carbonized.

In one embodiment of the present application, the irradiation of the ultraviolet rays may be performed for about 360 seconds to about 480 seconds for UVA, about 360 seconds to about 480 seconds for UVB, and about 360 seconds to 480 seconds for UVV. . When the ultraviolet irradiation is performed for less than the above range, the crosslinking reaction of the cation exchange precursor solution 700 may not proceed smoothly, and when performed during the above range, the porous polymer support 110 and the upper film 200 ) And the lower film 300 may be carbonized.

In one embodiment of the present application, in the step S200, after forming the cation exchange polymer electrolyte 120 as described above, a polymer support 110 including the formed cation exchange polymer electrolyte 120, and an upper film 200 And detaching the lower film 300 from the detachment roll.

In one embodiment of the present application, the crosslinked polymerized polymer resin 710 formed on the outside of the porous polymer support 110 is transferred to and removed from the upper film 200 and the lower film 300 through the desorption. I can.

In one embodiment of the present application, the gap between the upper and lower detachable rolls 500 and 550 is equal to the sum of the thicknesses of the porous polymer support 110 and the films 200 and 300 before being introduced into the pressing roll. Can be. At this time, the porous polymer support 110 before being added to the pressing roll refers to the polymer support 110 before being impregnated with the cation exchange precursor solution 700. That is, the thickness of the porous polymer support 110 may be the thickness of the polymer support 110 not including the cation exchange precursor solution 700.

In one embodiment of the present application, the detachment may be achieved by pulling the upper film 200 and the lower film 300 past the detachment roll from the other side, respectively, and the direction of the other side is the upper detachable roll 500 ) And from the lower detachable roll 550 may be in a diagonal direction, respectively.

Next, in one embodiment of the present application, the method of manufacturing the polyvalent ion exclusion type ion exchange membrane 1 is the cation exchange in an anion exchange precursor solution 700 including an electrolyte monomer having a cationic group, a crosslinking agent, an initiator, and a solvent. The polymer electrolyte 120 includes a step (S300) of impregnating the porous polymer support 110 formed therein.

In one embodiment of the present application, the electrolyte monomer having the cationic group may be a quaternary ammonium salt electrolyte monomer, for example, (3-acrylamidopropyl) trimethylammonium chloride [(3-acrylamidopropyl)trimethylammonium chloride], It may include a material selected from the group consisting of (vinylbenzyl)trimethylammonium chloride [(vinylbenzyl)trimethylammonium chloride] and combinations thereof.

In one embodiment of the present application, the crosslinking agent and initiator may be the same as those used in step S100.

In one embodiment of the present application, the content of the electrolyte monomer having a cationic group is about 53 parts by weight to about 60 parts by weight, the content of the crosslinking agent is about 3 parts by weight to about 7 parts by weight, and the content of the solvent is about 33 parts by weight. It may be mixed in a ratio of parts to about 44 parts by weight, and the content of the initiator may be from about 0.1 parts by weight to about 0.5 parts by weight based on 100 parts by weight of a solution in which the electrolyte monomer having a cationic group, a crosslinking agent, and a solvent are mixed. When the content of the electrolyte monomer having a cationic group is less than the above range, the ion exchange capacity capable of improving the ion conductivity of the produced ion exchange membrane may be insufficient, and when it exceeds the above range, the durability of the produced ion exchange membrane may be reduced. In addition, when the content of the crosslinking agent is less than the above range, durability of the produced ion exchange membrane may be reduced due to insufficient crosslinking degree, and when the content of the crosslinking agent is exceeding the above range, the degree of crosslinking may be too high and the ionic conductivity of the produced ion exchange membrane may be significantly reduced.

Next, in one embodiment of the present application, in the method of manufacturing the polyvalent ion exclusion type ion exchange membrane, the porous polymer by irradiating light to the porous polymer support impregnated with the anion exchange precursor solution to crosslink the anion exchange precursor solution. And forming an anion exchange polymer electrolyte on the surface of the support (S400).

In the exemplary embodiment of the present application, the step S400 may be performed according to the roll-to-roll process shown in FIG. 3 in the same manner as the step S200, and the following process is the same as the above, so a description thereof will be omitted.

In one embodiment of the present application, the content of the anion exchange polymer electrolyte 130 may be 10% to 40% of the content of the cation exchange polymer electrolyte 120. When the content of the anion exchange polymer electrolyte 130 is less than 10%, polyvalent cations can also pass through the polyvalent ion exclusion type ion exchange membrane 1, so that only monovalent cations cannot be selectively permeated. Too many cationic groups in the exchange polymer electrolyte 130 may cause a problem in that monovalent cations are also impermeable.

In one embodiment of the present application, in the prepared polyvalent ion exclusion type ion exchange membrane 1, the anion exchange polymer electrolyte 130 is not formed outside the polymer support 110, and the polyvalent ion exclusion type ion exchange membrane ( The porous structure of the polymer support 110 may be exposed on the surface of 1).

In one embodiment of the present application, the meaning that the anion exchange polymer electrolyte 130 is not formed outside of the polymer support 110 should be interpreted as including that at least some of them may be formed. In addition, the exposure of the porous structure of the polymer support 110 to the surface of the polyvalent ion exclusion type ion exchange membrane 1 should be interpreted to mean that at least a portion of the porous structure may be exposed, and the polymer support 110 It should be interpreted that the porous structure of the surface is exposed.

In one embodiment of the present application, the polyvalent ion exclusion type ion exchange membrane 1 has no by-products on the surface by removing the crosslinked polymerized polymer resin formed on the outside of the porous polymer support 110, and the thickness of the ion exchange membrane 1 Can have thin properties.

In one embodiment of the present application, the weight (weight) ratio of the polymer support 110 and the ion exchange polymer electrolyte (cation exchange polymer electrolyte 120 and anion exchange polymer electrolyte 130) is 1: 0.8 to 1: 1.1 Can be When the weight ratio of the ion exchange polymer electrolyte filled in the polymer support 110 is less than 1:0.8, the ion exchange polymer electrolyte may not be sufficiently filled, and thus it may be difficult to express physical and electrochemical properties as an ion exchange membrane to be implemented. When the weight ratio is more than 1:1.1, the polymer electrolyte remains on the surface of the polyvalent ion exclusion type ion exchange membrane 1, and thus it may be difficult to form a uniform ion exchange membrane.

Hereinafter, embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the present invention. However, the present invention may be implemented in various different forms and is not limited to the embodiments described herein.

<Example 1> Preparation of polyvalent ion exclusion type ion exchange membrane (including 12% anion exchange polymer electrolyte based on the content of cation exchange polymer electrolyte)

1. Cation exchange polymer electrolyte filling

A mixture of acrylamide-2-methyl-1-propanesulfonic acid (99%), N,N'-ethylenebisacrylamide and water in a weight ratio of 6:1:6 A polymerization solution was prepared, and an initiator solution in which N,N'-azobisisobutyronitrile was diluted in methanol at a 10 weight ratio was used in a 0.01 weight ratio. After that, a porous polyethylene support with a thickness of 30 μm and a pore distribution of 40% is impregnated into the mixed solution so that the monomer can sufficiently penetrate into the support, and then crosslinked in an oven at 80°C for 2 hours, placing it between the polyethylene terephthalate (PET) films. The reaction was carried out. After performing the crosslinking process, the PET film was removed, and by-products adhering to the surface of the support were removed to obtain a cation exchange membrane.

2. Filling of anion exchange polymer electrolyte (12% of the content of cation exchange polymer electrolyte)

In order to fill both surfaces of the cation exchange membrane prepared by the above 1. cation exchange polymer electrolyte filling, vinylbenzyltrimethylammonium chloride ((vinylbenzyl)trimethylammonium chloride, 99%), N,N'-ethylenebis The cation exchange membrane prepared by 1 is impregnated with a solution of acrylamide and water in a weight ratio of 12:1:12, so that the solution can sufficiently penetrate into pores that are less filled on the surface of the cation exchange membrane prepared by 1 above. After making it so that it was placed between polyethylene terephthalate (PET) films, a crosslinking reaction was performed in an oven at 80°C for 2 hours, and then the PET film was removed and by-products on the surface of the support were removed to obtain a monovalent selective cation exchange membrane.

<Example 2> Preparation of polyvalent ion exclusion type ion exchange membrane (including 32% of anion exchange polymer electrolyte based on the content of cation exchange polymer electrolyte)

1. Cation exchange polymer electrolyte filling

A mixture of acrylamide-2-methyl-1-propanesulfonic acid (99%), N,N'-ethylenebisacrylamide and water in a weight ratio of 6:1:6 A polymerization solution was prepared, and an initiator solution in which Darocur 1173 was diluted in methanol at a 10 weight ratio was used in a 0.01 weight ratio. After that, a porous polyethylene support with a thickness of 16 μm (12-35 μm) and a pore distribution of 43% (40-50 %) is impregnated into the mixed solution so that the monomer can sufficiently penetrate into the support, and then a polyethylene terephthalate (PET) film It was irradiated with ultraviolet rays (30-150 mJ/cm ² ) for 6 minutes (5-10 minutes) for the first time between the ^two . After performing the crosslinking process, the PET film was removed, and by-products adhering to the surface of the support were removed to obtain a cation exchange membrane.

2. Filling of anion exchange polymer electrolyte (32% of the content of cation exchange polymer electrolyte)

In order to fill both surfaces of the cation exchange membrane prepared by the above 1. cation exchange polymer electrolyte filling, vinylbenzyltrimethylammonium chloride ((vinylbenzyl)trimethylammonium chloride, 99%), 1,4-bisacrylic The cation exchange membrane prepared by 1 is impregnated with a solution of ilpiperazine and water in a weight ratio of 12:1:4 so that the solution sufficiently penetrates into the pores less filled on the surface of the cation exchange membrane prepared by 1 above. After that, it was placed between polyethylene terephthalate (PET) films and irradiated with ultraviolet rays (30-150 mJ/cm ² ) for 6 minutes (5-10 minutes) for a ^{second time} . After performing the secondary electrolyte filling and crosslinking process as described above, the PET film was removed and by-products on the surface of the support were removed to obtain a monovalent selective cation exchange membrane.

<Comparative Example 1> Preparation of pure cation exchange membrane (E2)

In order to compare the selectivity of the polyvalent ion exclusion type ion exchange membrane according to Examples 1 and 2, a pure cation exchange membrane was prepared as follows.

A mixture of acrylamide-2-methyl-1-propanesulfonic acid (99%), N,N'-ethylenebisacrylamide and water in a weight ratio of 6:1:6 A polymerization solution was prepared, and an initiator solution in which Darocur 1173 was diluted in methanol at a 10 weight ratio was used in a 0.01 weight ratio. After that, a porous polyethylene support with a thickness of 16 μm (12-35 μm) and a pore distribution of 43% (40-50 %) is impregnated into the mixed solution so that the monomer can sufficiently penetrate into the support, and then a polyethylene terephthalate (PET) film It was irradiated with ultraviolet rays (30-150 mJ/cm ² ) for 6 minutes (5-10 minutes) for the first time between the ^two . After performing the crosslinking process, the PET film was removed and by-products on the surface of the support were removed to obtain a primary cation exchange membrane.

Next, a second cation exchange membrane was obtained by filling and crosslinking the first prepared cation exchange membrane in the same manner as above using a mixed solution of the same composition.

<Comparative Example 2> Preparation of a commercial cation exchange membrane (CMV)

It was compared with the Examples using a commercially available monovalent cation exchange membrane (Asahi Glass, Japan).

<Experimental Example>

After mounting the ion exchange membranes according to the above Examples and Comparative Examples in the measuring device shown in FIG. 4, an aqueous solution of 1 normal concentration of sodium chloride, magnesium chloride or calcium chloride was contained in the vessel on the left side of the membrane, and distilled water was contained in the vessel on the right side of the membrane. Conductivity was measured for 2 hours to determine the amount of ions in the aqueous solution permeating through the membrane sample over time. By measuring the conductivity of each solution, the result was converted into a concentration, and the change in concentration over time is shown in FIG. 2.

In addition, the results of calculating the membrane permeability (P _crossover ), the membrane resistance (Area resistance), etc. to ion crossover using the following equation are shown in Table 1 below.

(Wherein, V is a transmission cell on both sides for measuring (solution volume of the ion is supplied to the containing side and pure side) the same amount (cm ^3), L is an ion exchange membrane thickness (cm), A used in the permeability measurement Or S is the effective area of the ion exchange membrane used for measuring the permeability or sheet resistance (cm ² ), C _A is the initial ion concentration in the solution containing the ions (M), and C _B (t) is the change in time to the pure water. The concentration of the corresponding ion (M), t is the changed time at the time of measurement (s), t ₀ is the initial time before measurement (s), R ₁ is the resistance of the solution including the membrane (Ω), and R ₂ is the resistance of the solution only ( Ω))

[Table 1]

5A to 5D and Table 1, unlike the cation exchange membranes according to Comparative Examples 1 and 2, the cation exchange membranes according to Examples 1 and 2 herein have a degree of permeation of a monovalent cation (Na ⁺ ) and a divalent cation (Ca ^{2+ ).} And Mg ²⁺ ) is significantly higher than the degree of permeation, it can be confirmed that the selectivity for monovalent cations is significantly superior to the cation exchange membrane according to Comparative Examples 1 and 2.

Table 2 below shows the ratio of the transmittance of MgCl ₂ and CaCl ₂ based on the transmittance of NaCl of the cation exchange membrane according to the present Examples and Comparative Examples, as confirmed through FIGS. 5A to 5D and Table 1 above, The cation exchange membranes according to Examples 1 and 2 have remarkably superior selectivity to monovalent cations compared to the cation exchange membranes according to Comparative Examples 1 and 2, and in particular, in the case of the cation exchange membrane according to Example 2, monovalent cations (Na ⁺ ) It exhibited a selectivity of more than 10 times compared to the secondary cations (Ca ²⁺ and Mg ²⁺ ).

[Table 2]

1: polyvalent ion exclusion type ion exchange membrane
101: roll-to-roll processing equipment
110: porous polymer support
120: cation exchange polymer electrolyte
130: anion exchange polymer electrolyte
200: upper film
300: lower film
400: upper pressing roll
450: lower pressing roll
500: upper detachable roll
550: lower detachment roll
600: ultraviolet irradiation device
700: ion exchange precursor solution
710: crosslinked polymerized polymer resin

Claims (14)

A polymeric support having a porous structure; And
An ion exchange polymer electrolyte impregnated in the polymer support;
As a polyvalent ion exclusion type ion exchange membrane containing,
The ion exchange polymer electrolyte includes a cation exchange polymer electrolyte and an anion exchange polymer electrolyte,
A cation exchange polymer electrolyte is impregnated in the center of the polymer support,
An anion exchange polymer electrolyte is impregnated on the surface of the polymer support,
The content ratio of the cation exchange polymer electrolyte and the anion exchange polymer electrolyte has the relationship of the following formula 1,
A polyvalent ion exclusion type ion exchange membrane, wherein the content ratio of the cation exchange polymer electrolyte to the anion exchange polymer electrolyte increases from the surface to the center according to the thickness direction of the polymer support:
[Equation 1]
A ≥ B
In Equation 1 above,
A is the content ratio of the cation exchange polymer electrolyte to the anion exchange polymer electrolyte in the center of the polymer support,
B is the content ratio of the cation exchange polymer electrolyte to the anion exchange polymer electrolyte in the surface portion of the polymer support,
The center portion is a region from the surface to the center direction to a depth of 20% to 80% with respect to 100% of the thickness of the polymer support,
The surface portion is a region ranging from 0% to 20% in the center direction from the surface to 100% of the thickness of the polymer support.
delete delete The method of claim 1,
The content of the anion exchange polymer electrolyte is 10% to 40% of the content of the cation exchange polymer electrolyte polyvalent ion exclusion type ion exchange membrane.
The method of claim 1,
The cation exchange polymer electrolyte is a polyvalent ion exclusion type ion exchange membrane in which a sulfonic acid-containing electrolyte monomer having an anionic group is crosslinked and polymerized.
The method of claim 5,
The sulfonic acid-containing electrolyte monomer having an anionic group is 2-acrylamide-2-methylpropanesulfonate sodium, vinylsulfonate sodium, vinylsulfonic acid, Allyl sulfonate sodium, 2-methyl-2-propene-1-sulfonate sodium, 3-sulfopropyl acrylate sodium A polyvalent ion exclusion type ion exchange membrane comprising a material selected from the group consisting of acrylate sodium) and combinations thereof.
The method of claim 1,
The anion exchange polymer electrolyte is a polyvalent ion exclusion type ion exchange membrane obtained by crosslinking polymerization of an electrolyte monomer of a quaternary ammonium salt having a cationic group.
The method of claim 7,
Electrolytic monomers of the quaternary ammonium salt having a cationic group are (3-acrylamidopropyl) trimethylammonium chloride [(3-acrylamidopropyl)trimethylammonium chloride], (vinylbenzyl) trimethylammonium chloride [(vinylbenzyl)trimethylammonium chloride], and combinations thereof Multivalent ion exclusion type ion exchange membrane containing a material selected from the group consisting of.
The method of claim 1,
The porous polymer support is a polyvalent ion exclusion type ion exchange membrane having a pore volume of 40% to 50%, a pore size of 0.07 μm to 0.1 μm, and a thickness of 8 μm to 30 μm.
The method of claim 1,
The thickness ratio of the polyvalent ion exclusion type ion exchange membrane to the thickness of the polymer support is 1.0 to 1.03.
Impregnating a porous polymer support in a cation exchange precursor solution containing an electrolyte monomer having an anionic group, a crosslinking agent, an initiator, and a solvent;
Irradiating light to the porous polymer support to crosslink the cation exchange precursor solution to form a cation exchange polymer electrolyte in the center of the porous polymer support;
Impregnating an anion exchange precursor solution comprising an electrolyte monomer having a cationic group, a crosslinking agent, an initiator, and a solvent with a porous polymer support having the cation exchange polymer electrolyte formed therein; And
Forming an anion exchange polymer electrolyte on the surface of the porous polymer support by irradiating light to the porous polymer support impregnated with the anion exchange precursor solution to crosslink the anion exchange precursor solution;
As a method for producing a polyvalent ion exclusion type ion exchange membrane comprising,
The polyvalent ion exclusion type ion exchange membrane prepared by the above manufacturing method,
The content ratio of the cation exchange polymer electrolyte and the anion exchange polymer electrolyte has the relationship of the following formula 1,
A method of manufacturing a polyvalent ion exclusion type ion exchange membrane, wherein the content ratio of the cation exchange polymer electrolyte to the anion exchange polymer electrolyte increases from the surface to the center according to the thickness direction of the polymer support:
[Equation 1]
A ≥ B
In Equation 1 above,
A is the content ratio of the cation exchange polymer electrolyte to the anion exchange polymer electrolyte in the center of the polymer support,
B is the content ratio of the cation exchange polymer electrolyte to the anion exchange polymer electrolyte in the surface portion of the polymer support,
The center portion is a region from the surface to the center direction to a depth of 20% to 80% with respect to 100% of the thickness of the polymer support,
The surface portion is a region ranging from 0% to 20% in the center direction from the surface to 100% of the thickness of the polymer support.
The method of claim 11,
The method of manufacturing a polyvalent ion exclusion type ion exchange membrane, wherein the electrolyte monomer having an anionic group is an electrolyte monomer containing sulfonic acid.
The method of claim 11,
The method of manufacturing a polyvalent ion exclusion type ion exchange membrane, wherein the electrolyte monomer having a cationic group is a tetravalent ammonium salt electrolyte monomer.
The method of claim 11,
The method of manufacturing a polyvalent ion exclusion type ion exchange membrane, wherein the porous polymer support is hydrophilized with a surfactant before being impregnated with the cation exchange precursor solution.

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