KR102021286B1 - Ion exchange membrane and method for manufacturing thereof - Google Patents

Abstract

A method for producing an ion exchange membrane is provided. The method of manufacturing an ion exchange membrane according to an embodiment of the present invention includes the steps of electrospinning a spinning solution in which a support component and an ion exchange component are mixed to prepare a fiber mat. This makes it easy to adjust the thickness, electrical conductivity, mechanical strength, and pore diameter / ratio of the membrane to suit the use of the ion exchange membrane in the manufacturing process, and simplify the manufacturing process. It can be used as a general-purpose ion exchange membrane having mechanical strength and durability, and at the same time having a large ion exchange capacity and a small electric resistance and diffusion coefficient.

Description

Ion exchange membrane and method for manufacturing

The present invention relates to an ion exchange membrane, and more particularly, the ion exchange membrane prepared at the same time through a simplified manufacturing process and short production time has a high ion exchange capacity while having excellent mechanical strength and durability, electrical resistance and diffusion It relates to an ion exchange membrane having a small coefficient and a method of manufacturing the same.

Ion exchange resins are synthetic resins with ion exchange capacity. In 1935, B. A. Adams and F. L. Holmes of England found ion exchange between a polyhydric phenol condensed with formaldehyde and a m-phenylenediamine condensed with formaldehyde. It has been found that this resin can remove various ions in water, and then began production on a systematic and industrial scale in Germany and the United States. During World War II, Germany was used to purify water, recover copper and ammonia from artificial dog factories, and to classify nuclear fission products, ultrauranium elements, and rare earth elements in the United States. In addition, the purification of various substances (amino acids, antibiotics, etc.) was facilitated by ion exchange resins, and since the development of ion exchange membranes, electrochemical chemicals have played a more important role. Currently, ion exchange membranes are widely used in fields such as fuel cells, redox flow batteries, electrodialysis, desalination, ultrapure water and wastewater treatment. In particular, by reducing the use of fossil fuels, it is attracting worldwide attention for its clean technology for eco-friendly renewable energy production. Due to the rapid increase in the use of electronic products such as small notebooks and mobile phones, research on the ion exchange membrane, which is the core material, is actively conducted according to the necessity of developing a high-life, high-capacity battery and a new fuel cell.

On the other hand, conventional ion exchange membranes are often provided with a separate support to improve mechanical properties, specifically, a sheet-like ion exchange resin layer may be provided on one surface of the support, due to the material of the support and the ion exchange resin layer Peeling and separation frequently occur between interlayer interfaces due to compatibility and the like, and thus there is a problem in that ion exchange capacity and / or mechanical properties are significantly reduced. In addition, in the manufacturing process of the ion exchange membrane, there is a problem that it is very difficult to change the configuration, for example, controlling the thickness, electrical conductivity, mechanical strength, diameter / ratio of the pores, and the like to suit the purpose.

As a result, it is easy to change the structure and physical properties of the ion exchange membrane to suit the application even in the simplified process, and the manufactured ion exchange membrane has excellent mechanical strength and durability, high ion exchange capacity, and low electrical resistance and diffusion coefficient. There is an urgent need for research on ion exchange membranes and processes that can more easily implement such ion exchange membranes.

Republic of Korea Patent Publication No. 2014-0036609

The present invention has been devised in view of the above-mentioned point, and it is easy to control factors such as membrane thickness, electrical conductivity, mechanical strength, and diameter / ratio of pores to suit the purpose in the manufacturing process of ion exchange membrane, It is an object of the present invention to provide a method for producing an ion exchange membrane, in which a fabrication process is greatly simplified such that a filling process is omitted.

Another object of the present invention is to provide a general-purpose ion exchange membrane having excellent mechanical strength and physical / chemical durability and at the same time a large ion exchange capacity and a low electrical resistance and diffusion coefficient.

In order to solve the above problems, the present invention provides a method for producing an ion exchange membrane comprising (1) preparing a fiber mat by electrospinning a spinning solution in which a support component and an ion exchange component are mixed.

According to an embodiment of the present invention, the support component is polyimide, polyamic acid, polycarprolactone, polyetherimide, nylon, nylon, polyaramid ), Polybenzyl-glutamate, polyphenyleneterephthalamide, polyaniline, polyacrylonitrile, polyethylene oxide, polystyrene, cellulose, Polymethylmethacrylate, polylactic acid (PLA), polyglycolic acid (PGA), polylactic-co-glycolic acid, poly {poly (ethylene oxide) terephthalate-co-butyl Lenterephthalate} (PEOT / PBT), polyphosphoester (PPE), polyphosphazene (PPA), polyanhydride (PA), polyorthoester {poly (ortho ester; POE}, poly (propylene fumarate) -diacrylate (poly (propylene fumarate) -diacrylate; PPF-DA}, polyvinyl alcohol, polyester, polyurethane, polyvinyl chloride, polytetrafluoroethylene (PTFE, polytetra fluoroethylene), polyethylene tetrafluoro ethylene (ETFE), polyvinylidene fluoride (PVDF), ethylene chloro trifluoro ethylene (ECTFE, Ethylene Chlorotrifluoroethylene) and polychlorotrifluoro It may include one or more selected from the group consisting of ethylene (PCTFE, polychlorotrifluoro ethylene) and poly (styrene-co-maleic anhydride).

In addition, the ion exchange component may be a cationic ion exchange component or an anionic ion exchange component.

In addition, the spinning solution may include 20 to 80 parts by weight of an ion exchange component based on 100 parts by weight of the support component.

In addition, after the step (1), (2) applying heat and pressure to the fiber mat to adjust the porosity and pore size; may further include a.

In addition, the melting point of the support component included in the fiber mat may be lower than the melting point of the ion exchange component.

In addition, the present invention provides an ion exchange membrane comprising a; fiber mat comprising a first fiber comprising a support component and an ion exchange component.

According to an embodiment of the present invention, the fibrous mat may further include a second fiber including a support component and a third fiber including an ion exchange component.

In addition, the fiber mat may include a web region of a three-dimensional network structure formed by fusion between fibers.

In addition, the average diameter of the fibers included in the fiber mat is 0.1 ~ 100㎛, the average pore diameter of the island fiber mat may be 0.1 ~ 10㎛, the thickness of the fiber mat may be 0.1 ~ 200㎛.

In this case, the ion exchange membrane may be used for the filter for the liquid, the filter for the air.

In addition, the present invention is a fiber mat comprising a third fiber comprising an ion exchange component; And a support for filling the interfiber space in the fiber mat to support the third fiber.

According to an embodiment of the present invention, the ion exchange membrane may be a liquid filter, an air filter, a capacitive deionization (CDI), an electrodialysis (ED), or a battery separator.

Hereinafter, the term used by this invention is demonstrated.

The term " surface portion " of a mat used in the present invention is meant to include an area corresponding to a thickness of 15% or less of the total thickness of the mat from the mat surface.

The term "mat" used in the present invention means a state in which the electrospun fibers are accumulated, and the mat is formed by bending and entangled fibers of a plurality of times or by plural fibers being entangled with each other. It may be formed, and even if some of the fibers are melted to include a non-fibrous portion, the fibrous portion may be included in the "mat".

According to the present invention, the electrical conductivity, mechanical strength, voids, etc. can be easily adjusted according to the required characteristics according to the use of the ion exchange membrane, and the filling process of the ion exchange solution is omitted. Can be produced, which can significantly increase productivity. In addition, the ion exchange membrane prepared by expressing the effect of significantly increasing the filling capacity of the ion exchange component inside the support has excellent mechanical strength and durability, at the same time has a large ion exchange capacity, and has low electrical resistance and diffusion coefficient. Accordingly, the present invention can be widely applied to separators in the battery field, desalination systems such as CDI / ED, various materials, and the like, and may be particularly suitable for battery separator applications.

1 is a schematic view of the manufacturing process of the ion exchange membrane according to an embodiment of the present invention,
Figure 2 is a schematic cross-sectional view of the ion exchange membrane prepared through Figure 1, and
3 is a schematic diagram partially enlarged between fibers and fibers in the ion exchange membrane according to FIG. 2.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. The drawings and description are to be regarded as illustrative in nature and not restrictive. Like reference numerals designate like elements throughout the specification.

Referring to Figure 1 illustrates a method for producing an ion exchange membrane according to an embodiment of the present invention, the spinning solution is mixed with a support component and an ion exchange component through a plurality of electrospinning tips 10 to the fiber The integrated fiber mats 21 to 25 may be manufactured.

The spinning solution may include a support component and an ion exchange component, and the spinning solution may be a melt solution in which the support component and the ion exchange component are mixed / melted or a solution in which the components are dissolved by a solvent. The spinning solution may include from 20 to 80 parts by weight, more preferably from 30 to 60 parts by weight of the ion exchangeable component with respect to 100 parts by weight of the support component. If the ion exchangeable component is included in less than 20 parts by weight, the ion exchange capacity may be significantly lowered. If the ion exchangeable component is included in an amount greater than 80 parts by weight, the spinning ability may be remarkably decreased, such as spinning into beads. Can be.

The support component may be used without limitation in the case of a compound used as a component of a support in a conventional ion exchange membrane, preferably polyimides, polyamic acid, polycarprolactone, polyether Polyetherimide, nylon, polyaramid, polybenzyl-glutamate, polyphenyleneterephthalamide, polyaniline, polyacrylonitrile, polyethylene oxide (polyacrylonitrile) polyethylene oxide, polystyrene, cellulose, polymethylmethacrylate, polylactic acid (PLA), polyglycolic acid (PGA), polylactic-co-glycolic acid , Poly {poly (ethylene oxide) terephthalate-co-butylene terephthalate} (PEOT / PBT), polyphosphoester; PPE), polyphosphazene (PPA), polyanhydride (PA), poly (ortho ester; POE}, poly (propylene fumarate) -diacrylate {poly (propylene fumarate)- diacrylate; PPF-DA}, polyvinyl alcohol, polyester, polyurethane, polyvinyl chloride, polytetrafluoroethylene (PTFE, polytetra fluoroethylene), polyethylene tetrafluoro ethylene (ETFE), polyvinylidene fluorine 1 selected from the group consisting of polyvinylidene fluoride (PVDF), ethylenechlorotrifluoroethylene (ECTFE), polychlorotrifluoroethylene (PCTFE) and poly (styrene-co-maleic anhydride) It may be more than one species. However, the present invention is not limited thereto, and components may be changed according to the use of the ion exchange membrane.

In addition, when the support component contains at least two kinds of support components, for example, polyacrylonitrile (PAN) as a heat resistant support component and polyvinylidene fluoride (PVDF) as an adhesive support component (or swellable support component). ) May be mixed, and it is preferable to mix each component in a weight ratio range of 8: 2 to 5: 5.

When the mixing ratio of the heat resistant support component and the adhesive support component is less than 5: 5 by weight, the heat resistance is poor and does not have the required high temperature characteristics. When the mixing ratio is larger than 8: 2 by weight ratio, the strength drops and radiation trouble occurs.

The heat resistant support component is a resin that can be dissolved in an organic solvent for electrospinning and has a melting point of 180 or more, for example, polyacrylonitrile (PAN), polyamide, polyimide, polyamideimide, poly (meth-phenyl Isophthalamide), polysulfone, polyetherketone, polyethylene terephthalate, polytrimethylene telephthalate, polyethylene naphthalate and the like, aromatic polyesters, polytetrafluoroethylene, polydiphenoxyphosphazene, poly {bis [ 2- (2-methoxyethoxy) phosphazene]}, polyurethane copolymers including polyurethane and polyetherurethane, cellulose acetate, cellulose acetate butylate, cellulose acetate propionate, and the like. Can be.

The swellable support component is a resin that swells in the electrolyte and can be formed into ultrafine fibers by electrospinning, for example, polyvinylidene fluoride (PVDF), poly (vinylidene fluoride-co-hexafluoropropylene) , Polyethylene glycol derivatives including perfuluropolymer, polyvinyl chloride or polyvinylidene chloride and copolymers thereof and polyethylene glycol dialkyl ether and polyethylene glycol dialkyl ester, poly (oxymethylene-oligo-oxyethylene), Polyoxides comprising polyethylene oxide and polypropylene oxide, polyvinylacetate, poly (vinylpyrrolidone-vinylacetate), polystyrene and polystyrene acrylonitrile copolymers, polyacrylonitrile methyl methacrylate copolymers Acrylonitrile Copolymer, Poly Methyl methacrylate, polymethyl methacrylate copolymer, and mixtures thereof are mentioned.

Next, the ion exchange component may be a cationic ion exchange component or an anionic ion exchange component, and a cation exchange membrane or an anion exchange membrane may be implemented according to the polarity of the ion selected.

The cationic ion exchange component is quaternary ammonium salt (-NH ₃ ), primary to tertiary amine (-NH ₂ , -NHR, -NR ₂ ), quaternary phosphonium group (-PR ₄ ), tertiary sulfony It may be a high molecular compound having an anion-exchange functional group such as carboxyl group (-SR ₃ ).

In addition, the anionic ion-exchangeable component is a sulfonic acid group (-SO ₃ H), carboxyl group (-COOH), phosphonic group (-PO ₃ H ₂ ), phosphonic group (-HPO ₂ H), isonic group ( It may be a high molecular compound having a cation exchange functional group, such as -AsO ₃ H ₂ ), selenic group (-SeO ₃ H), specifically, can be used polysulfone, polyisulfone and the like.

In addition, the cationic or anionic ion exchange component is a hydroxyl group (-OH), an amine group (-NH ₂ , -NH-, -NR-, -NR ₂ which can be crosslinked by an ester bond with a crosslinking functional group. ) And a polymer compound having a carboxylic acid group (-COOH) and a condensation polymerization type crosslinking reaction group containing an isocyanate functional group capable of bonding an epoxy group or a urethane, or a crosslinking reaction by addition polymerization. A polymer compound having a heavy bond structure may be used, and such a polymer resin may be present in a solution form by dissolving in an organic solvent. Specifically, for example, polystyrene, polysulfone, polyisulfone, polyamide, polyester Any one or two or more selected from polyimide, polyether, polyethylene, polytetrafluoroethylene, polyglycidyl methacrylate You can use the water.

Next, when the spinning solution is a dissolving solution, a solvent may be further included. The solvent may be used without limitation in the case of a solvent used in a conventional electrospinning spinning solution, but it is soluble in a supporting component and an ion exchange component. This excellent solvent is preferred. In addition, it is preferable in the case of a solvent that can be easily evaporated, and the present invention is not particularly limited as the solvent may be differently selected according to the kind of the supporting component and the ion exchangeable component specifically selected. Preferably, γ-butyrolactone, cyclohexanone, 3-hexanone, 3-heptanone, 3-octanone, N-methylpyrrolidone, dimethylacetamide, dimethyl sulfoxide, acetic acid, toluene, formic acid , Acetone, chloroform, dichloromethane, trichloroethylene, ethanol, methanol, normal hexane and dimethylformamide may be used a single solvent selected from the group consisting of or a mixed two-component solvent. The two-component mixed solvent may be a two-component mixed solvent in which a high boiling point solvent and a low boiling point solvent are mixed, and the mixing ratio between the two-component mixed solvent and the entire supporting component is preferably set to about 8: 2 by weight, It is not limited to this.

In addition, when using a single solvent, considering that the solvent may not be volatilized well depending on the type of the supporting component after passing through the pre-air dry zone (Pre-Air Dry Zone) by the pre-heater after the spinning process will be described later The process of controlling the amount of solvent and water remaining on the surface of the fiber mat may be further processed.

The spinning solution described in step (1) according to the present invention may be added to a conventional electrospinning apparatus. The electrospinning device may be a device for wet spinning or dry spinning according to specific types of components included in the spinning solution to be selected.

For example, the spinning solution may be introduced into the supply unit of the electrospinning apparatus and transferred to the nozzle unit through a pump unit such as a known syringe pump. The nozzle unit may be configured of a nozzle and a connection unit connecting the nozzle to the supply unit. However, the nozzle may be coupled to the supply unit without a connection unit to form a nozzle unit, and thus the specific configuration of the nozzle unit is not particularly limited in the present invention, and the configuration of the nozzle unit included in the general electrospinning apparatus may be selected and changed.

The diameter of the nozzle of the nozzle unit may be selected in consideration of the basis weight, porosity, pore size, mechanical strength, etc. of the desired fiber mat, and the present invention is not particularly limited thereto. In addition, the cross-sectional shape of the nozzle may be a variety of shapes, such as circular, elliptical, polygonal, and the longitudinal cross-sectional shape of the nozzle may be a cross-sectional shape of a conventional electrospinning nozzle, such as single nozzle, double nozzle, triple nozzle. In addition, the nozzle unit may include a plurality of nozzles according to the purpose, and the present invention does not limit the specific shape, size, number, etc. of the nozzles, and so on. In addition, the material of the nozzle may be a material of the nozzle used in the normal electrospinning, and preferably may be a metal material having electrical conductivity, but is not limited thereto.

A portion of the nozzle portion may be connected in electrical communication with an electric field forming portion, for example a high voltage device, to form an electric field for electrospinning. The electric field forming unit is for forming a jet of the spinning solution from the nozzle unit to the collector, and is capable of forming an electric field between the nozzle tip of the nozzle unit and any one virtual point passing through the nozzle tip and the collector in a straight line. In this case, the present invention may be employed without limitation, and the configuration of the electric field forming unit provided in the general electrospinning apparatus may be selected, and thus the present invention is not particularly limited thereto. However, the electric field forming unit may include a current collector plate and a high voltage generator, the current collector plate may be grounded to the ground, and the high voltage generator may be electrically connected to the nozzle unit.

If wet electrospinning is performed, the collector may be further equipped with a coagulation bath. The coagulation bath may include an external coagulation solution for coagulating a jet of spinning solution into a fibrous form. The external coagulant may be used without limitation, such as water, organic solvent, the present invention is not particularly limited to the specific type, as a non-limiting example, hexane, benzene, ethanol, methanol, propanol, acetone Butaneol, dimethylformamide and tetrahydrofuran may be used, but not limited to one or more selected.

Meanwhile, the air gap, which is a vertical distance between the nozzle tip and the surface of the external coagulating solution of the collector or the coagulation bath, may be 0 to 50 cm, but is not limited thereto.

The ion exchange membrane prepared by the above-described manufacturing method includes a first fiber comprising a support component and an ion exchange component.

The fiber strand forming the fiber mat may be spun in a state containing both a support component and an ion exchange component, but some of the fibers included in the fiber mat are separated from each other by the phase separation between the components during the spinning process. The fiber mat may further include any one or more of a second fiber including a support component and a third fiber including an ion exchange component, as the component may form one strand of fiber, as shown in FIG. 2. The ion exchange membrane may include all of the first fibers 21a / 22b, the second fibers 21a, and the third fibers 22b.

Meanwhile, the fiber mat may include a web area having a three-dimensional network structure formed by fusion between fibers, and as shown in FIG. 3, the second fiber 21a and the other second fiber 22a. A portion of the surface is fused (B ₁ ), and a portion of the surface of the second fiber 21a and the third fiber 21b is fused (B ₂ ) can form a three-dimensional network structure. In addition, although not shown in FIG. 3, fusion may occur between the first fiber and the other first, second, or third fibers including both the support component and the ion exchange component.

The fusion does not mean only partial melting of the fiber through a separate heating process. Specifically, in the process of electrospinning, the solvent contained in the spinning solution is usually spun and then vaporized in air irrespective of the method of electrospinning. In the case of wet electrospinning, the remaining amount of the solvent which is not vaporized is dissolved in the external coagulation solution. Solvents that are present in the spun fiber that are not vaporized and / or dissolved entirely and can be removed can lead to the attachment of contact points or contact surfaces when contact between the fibers occurs.

When the three-dimensional network structure is formed in the fiber mat, the stable pore structure between the fibers can be formed and the mechanical strength of the fiber mat can be improved, thereby achieving the desired physical properties more easily.

On the other hand, the average diameter of the fibers included in the fiber mat may be 0.1 ~ 100㎛. If the diameter of the fiber is less than 0.1 [mu] m, the mechanical strength is weak, making it difficult to form a stable pore structure, which may be unsuitable for use in some applications, for example, filters, and the radioactivity may be reduced. In addition, if the diameter exceeds 100㎛ according to the use of the heat / pressure is applied through the step (2) to be described later melt the support component in the fiber is not easy to melt the support component, according to the pore diameter of the fiber mat, Porosity may not be easy to control. However, the diameter range of the fiber is not limited, and the fiber diameter range may be changed depending on the use of the ion exchange membrane.

The average pore diameter of the fiber mat may be 0.1 ~ 10㎛. If the average pore size is less than 0.1㎛ may have a problem that the flow rate is significantly reduced in the filter applications, if the average pore size exceeds 10㎛ there is a problem that the filtration efficiency in the filter use may be lowered. However, the mean pore size is not limited to the range, and the mean pore size may be changed according to the use of the ion exchange membrane.

In addition, the thickness of the fiber mat may be 0.1 ~ 200㎛, but is not limited thereto, the thickness may be changed according to the use.

On the other hand, the fiber mat can be adjusted in pore size and thickness according to the intended use of the ion exchange membrane through the step (2) to be described later, the heat applied above the melting point of the support component is part of the mono yarn containing the support component of the fiber Alternatively, melting all of them may affect the pore size and porosity of the fiber mat.

Specifically, the heat applied to the fiber mat may be a temperature of 60 to 180, the pressure may be 2 psi or less, but may be different depending on the specific use of the ion exchange membrane, the support component and the specific type of the ion exchange component is not limited thereto. .

In addition, in the case of an ion exchange membrane whose use of the ion exchange membrane is a liquid filter or an air filter, the heat and / or pressure applied may be low even if step (2) is omitted or step (2) is performed, and / or ( 2) The step execution time can be short. In addition, even if the same filter is used, the specific heat / pressure / run time may vary depending on the size of the target material to be filtered.

On the other hand, even if the step (2) described above does not go through the porosity / pore size through the adjustment of the diameter and / or hourly radiation dose of the plurality of spinning nozzles (11 to 15) in the step (1) in the manufacturing process as shown in FIG. The different mats 21 to 25 may be laminated with the fibrous mat 20, and thus, an ion exchange membrane having a gradient of pore size and / or porosity may be implemented from one surface portion of the fibrous mat to the other surface portion. .

On the other hand, the ion exchange membrane according to another preferred embodiment of the present invention may have a melting point of the material of the support fiber included in the support fiber mat is lower than the melting point of the ion exchange fiber material contained in the ion exchange fiber mat, (2) The heat and pressure applied through the step may melt at least some of the support components, thereby filling the melted support components in the interfiber fusion and / or pores in the fibrous mat.

Accordingly, the ion exchange membrane according to an embodiment of the present invention is implemented to include a fiber mat comprising a fiber including an ion exchange component and a support for filling the interfiber space in the fiber mat to support the fibers.

The fibers forming the fibrous mat may include an ion exchange component as the subject of the fiber forming component as the support component is melted by heat / pressure, and for some fibers, may include an unmelted support component. The support is formed by melting the support component contained in the first fiber or the support fiber contained in the second fiber of the fibers included in the fiber mat prepared through step (1), to fill the interfiber space in the fiber mat Porosity, pore size can be controlled and the bond between fibers with the ion exchangeable component as the subject can be increased to further improve the mechanical strength.

The porosity, pore size, etc. of the fiber mat may vary depending on the heat / pressure applied through the step (2), the melting point of the support component, and the capacitance is controlled by adjusting the porosity of the ion exchange membrane prepared through the step (2). It can be prepared to be suitable for the use of deacrination (CDI) or electrodialysis (ED).

Also, pore-free ion exchange membranes having a porosity of 5% or less, more preferably 3% or less, even more preferably 1% or less, and even more preferably 0% of porosity may be used in fuel cells or redox flow batteries. As the battery separator satisfies the required mechanical and electrical properties more remarkably, it may be very suitable as a battery separator.

On the other hand, the ion exchange membrane according to a preferred embodiment of the present invention may further include a separate support member, such as a non-woven fabric on one surface of the ion exchange membrane to supplement the mechanical strength. The support member is, for example, a nonwoven fabric made of a double structure PP / PE fiber coated with PE on the outer circumference of the PP fiber as a core, or a PET nonwoven fabric made of polyethyleneterephthalate (PET) fiber, a nonwoven fabric made of cellulose fiber. Any one may be used, but is not limited thereto. The basis weight, thickness, and the like of the nonwoven fabric may be changed and used according to the purpose, and are not particularly limited in the present invention.

In addition, depending on the purpose, the fiber mat and / or non-woven fabric may be coated or filled with an inorganic material, the inorganic material is nickel (Ni), copper (Cu), stainless steel (SUS), titanium (Ti), chromium (Cr), At least one metal of manganese (Mn), iron (Fe), cobalt (Co), zinc (Zn), molybdenum (Mo), tungsten (W), silver (Ag), gold (Au), aluminum (Al) Oxides thereof, and the like.

Although the present invention will be described in more detail with reference to the following examples, the following examples are not intended to limit the scope of the present invention, which will be construed as to aid the understanding of the present invention.

<Example 1>

First, 12 g of polyvinylidene fluoride (Arkema Co., Kynar761) as a supporting component was dissolved in a weight ratio of dimethylacetamide and acetone at 90:10 using 88 ° C. at 60 ° C. for 6 hours using a magnetic bar. Manufactured. Next, 12 g of APS (PolyStyrene: VinylBenzeneChloride: MethylMethAcrylate = 1: 1: 2) resin, an anion exchange resin, was dissolved in 88 g of dimethylacetamide at 60 ° C for 6 hours using a magnetic bar as an ion exchange component. Prepared. Thereafter, the first mixed solution and the second mixed solution were mixed again and stirred to prepare a spinning solution, but mixed so that the ion exchangeable component was 50 parts by weight based on 100 parts by weight of the supporting component. The prepared spinning solution was put in a solution tank of an electrospinning apparatus, and 15 µl / min / hole was discharged. At this time, the temperature of the spinning section was 28, the humidity was maintained at 45%, the distance between the collector and the spinning nozzle tip was 25cm.

Using a high voltage generator to give a spin nozzle pack (Spin Nozzle Pack) a voltage of 45kV or more and at the same time giving an air pressure of 0.05MPa per spin pack nozzle to spin as shown in Figure 1 to prepare a fiber mat. Thereafter, to dry the solvent and moisture remaining on the fiber mat, a calendering process was performed by applying heat and pressure at 140 and 1 kgf / cm 2 to obtain a total thickness of 95 μm and a porosity of 65%. Prepared.

<Examples 2 to 5>

Manufactured in the same manner as in Example 1, the contents of the support component and the ion exchangeable component of the spinning solution were changed as shown in Table 1 to prepare an ion exchange membrane as shown in Table 1 below.

Comparative Example 1

The preparation was carried out in the same manner as in Example 1, except that the support component was not included in the spinning solution to prepare an ion exchange membrane as shown in Table 1 below.

Comparative Example 2

To prepare a support fiber, 12 g of polyvinylidene fluoride (Arkema, Kynar761) was used as a support fiber forming component at 90:10 with a weight ratio of dimethylacetamide and acetone at 90:10. It was dissolved to prepare a spinning solution. The spinning solution was put into a solution tank of an electrospinning apparatus and discharged at a rate of 15 µl / min / hole. At this time, the temperature of the spinning section is 28 ℃, the humidity was maintained at 45%, the distance between the collector and the spinning nozzle tip was 25 cm. A spinneret pack was spun to give a spinning nozzle pack with a voltage of 45 kV or more and an air pressure of 0.05 MPa per spin pack nozzle to spin, thereby producing a support fiber mat having a thickness of 100 μm. Then, a calendering process was performed by applying heat and pressure at 140 and 1 kgf / cm 2 to dry the solvent and moisture remaining on the fiber mat, thereby preparing a support membrane having a total thickness of 95 μm. The support membrane was then dissolved in 8 g of an APS (PolyStyrene: VinylBenzeneChloride: MethylMethAcrylate = 1: 1: 2) resin, an anion-exchange resin, using a magnetic bar at 92 ° C. for 6 hours at a temperature of 60 ° C. After drying at 80 ° C., an ion exchange membrane was prepared as shown in Table 1 below.

Experimental Example

The following physical properties of the ion exchange membranes prepared in Examples and Comparative Examples were evaluated, and are shown in Table 1 below.

1. Dimensional change (%)

In order to measure the mechanical strength of the ion exchange membrane, the dimensional change of the membrane was measured. Specifically, the prepared membrane was immersed in distilled water for 24 hours, and the volume of the wet membrane (V _wet ) was measured, and the wet membrane was vacuum-dried again at 120 to 24 hours to measure the volume (V _dry ). These measured values were substituted in Equation 1 below to calculate the degree of dimensional change.

[Equation 1]

% Change = (V _wet -V _dry ) × 100 / V _dry

The larger the dimensional change, the poor the mechanical strength and the durability.

2. Sacrificiality

SEM photographs were taken at 2000 times magnification on the surface of the fiber mat to count the total number of beads and the number of beads on the photographed image, and then the sacrificial properties were calculated according to Equation 2 below.

[Equation 2]

3. Membrane Performance for Redox Flow Battery

After placing an ion exchange membrane with a surface area of 30 cm ² in the center, a pair of carbon felts (GF020, JMTG), a pair of graphite plates, a pair of current collector plates, and a hard plate are formed on both sides of the ion exchange membrane. End plates) sequentially and then include a charge / discharger (WBCS 3000, WonAtech), a pump, an anode electrolyte tank connected to one region of the cell divided into ion exchange membranes, and a cathode electrolyte tank connected to the other region of the cell. A redox flow cell was prepared. At this time, the anode electrolyte tank was filled with 40 ml of a solution containing 2.0 M sulfuric acid and 1.0 M vanadium oxysulfate, and the cathode electrolyte tank was filled with 40 ml of a solution containing 2.0 M sulfuric acid and V3 + 1.0 M.

Charging proceeded to 1.5V while maintaining the current density at 60mA / cm ² , and discharge proceeded to 1.0V at the same current density to measure the performance of the charge / discharge cycles.

At this time, by measuring the change in voltage with time in each cycle was calculated the energy efficiency in each cycle according to the following Equation 3, the rest of the implementation based on the energy efficiency of Example 1 100% in 10 charge / discharge cycles The energy efficiency was displayed relative to 10 charge / discharge cycles of the examples and the comparative examples. In addition, the cycles in which the 2% energy efficiency decreased compared to the energy efficiency in the first 1 cycle of each example / comparative example were also indicated.

 [Equation 3]

(Energy Efficiency: Energy Efficiency, Id: Discharge Current, Ic: Charge Current, V: Discharge Voltage, VC: Charge Voltage, t: Charge Time or Discharge Time)

Example 1 Example 2 Example 3 Example 4 Example 5 Comparative Example 1 Comparative Example 2 Spinning solution Support ingredient content (parts by weight) 100 100 100 100 100 0 100 Ion exchange component content (parts by weight) 50 10 25 75 90 100 0 Ion exchange membrane Dimensional change (%) 9 2 4 12 25 68 One Sacrifice (%) 99 100 100 96 78 76 100 Energy efficiency (%) 100 46 78 106 110 25 109 Cycles when energy efficiency is reduced by 2% 716 902 705 658 493 14 730

As can be seen from Table 1 above,

In Comparative Example 1, in which the ion-exchange membrane was manufactured using only ion-exchange fibers, the durability was not good as the dimensional change was significantly greater than in the Examples, and the energy efficiency in 10 charge / discharge cycles was 25% compared to that of Example 1. It is only a case, and it can be seen that energy efficiency cannot be maintained for a long time.

On the other hand, Comparative Example 2, which is a conventional ion exchange membrane filled with an ion exchange solution in the support membrane, has a somewhat superior physical property compared with Example 1, but Example 1 is more excellent in productivity as the immersion time is required separately. You can check it.

In addition, in Examples 2 and 5, the content of the ion-exchangeable components in the spinning solution is too low or excessive, it can be confirmed that it is difficult to satisfy all the physical properties at the same time compared to Example 1.

Although one embodiment of the present invention has been described above, the spirit of the present invention is not limited to the embodiments set forth herein, and those skilled in the art who understand the spirit of the present invention, within the scope of the same idea, the addition of components Other embodiments may be easily proposed by changing, deleting, adding, and the like, but this will also fall within the spirit of the present invention.

10: electrospinning tip 20: fiber mat

Claims (14)

(1) electrospinning a spinning solution in which an ion exchange component and a support component having a lower melting point than that of the ion exchange component are dissolved to produce a fiber mat comprising fibers partially or entirely formed of the ion exchange component; And
(2) applying heat, heat, or pressure to the fiber mat such that some or all of the support components are melted to control porosity and pore size; and a method for producing an ion exchange membrane. The method of claim 1,
The support component may be polyimides, polyamic acid, polycarprolactone, polyetherimide, nylon, nylon, polyaramid, polybenzyl-glutamate ), Polyphenyleneterephthalamide, polyaniline, polyacrylonitrile, polyethylene oxide, polystyrene, cellulose, polymethylmethacrylate, Polylactic acid (PLA), polyglycolic acid (PGA), polylactic-co-glycolic acid, poly {poly (ethylene oxide) terephthalate-co-butylene terephthalate} (PEOT / PBT) , Polyphosphoester (PPE), polyphosphazene (PPA), polyanhydride (PA), poly (ortho ester; POE}, poly (propylene fu Poly (propylene fumarate) -diacrylate; PPF-DA}, polyvinyl alcohol, polyester, polyurethane, polyvinyl chloride, polytetrafluoroethylene (PTFE), polyethylenetetraflow Polyethylene tetrafluoro ethylene (ETFE), polyvinylidene fluoride (PVDF), ethylene chloro trifluoro ethylene (ECTFE) Styrene-co-maleic anhydride) at least one selected from the group consisting of ion exchange membrane. The method of claim 1,
Wherein said ion exchange component is a cationic ion exchange component or an anionic ion exchange component. The method of claim 1,
The spinning solution is a method for producing an ion exchange membrane containing 20 to 80 parts by weight of an ion exchange component with respect to 100 parts by weight of the support component. delete delete A first fiber comprising an ion exchange component and a support component having a lower melting point than the ion exchange component, a second fiber comprising the support component, and a third fiber comprising the ion exchange component; And a fibrous mat in which part or all of the components are melted so that part or all of the space formed between the first fiber, the second fiber, and the third fiber is embedded. delete The method of claim 7, wherein
The fiber mat comprises a web region of a three-dimensional network structure formed by fusion between fibers. The method of claim 7, wherein
An average diameter of the fiber is 0.1 ~ 100㎛ ion exchange membrane. The method of claim 7, wherein
The average diameter of the fiber mat is 0.1 ~ 10㎛ ion exchange membrane. The method of claim 7, wherein
The thickness of the fiber mat is 0.1 ~ 200㎛ ion exchange membrane. A fiber mat comprising a third fiber comprising an ion exchange component; And
And a support for supporting a third fiber by filling a space between fibers in the fiber mat through melting of a support component having a lower melting point than the ion exchange component. The method according to any one of claims 7 and 9 to 13,
The ion exchange membrane is an ion exchange membrane for liquid filters, air filters, capacitive deionization (CDI), electrodialysis (ED) or battery separation membrane.

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