KR20210002166A - The organic-inorganic composite electrolyte membrane, a method for producing the same, and an application product including the membrane - Google Patents

Abstract

The present invention relates to an organic/inorganic reinforced composite electrolyte membrane and a method of manufacturing the same. More particularly, the present invention relates to: an organic/inorganic reinforced composite electrolyte membrane having a low transmittance characteristic by crosslinking an organic polymer and an inorganic polymer impregnated in a porous support to generate silica particles, a method of manufacturing the same, and an application product including the membrane. The organic/inorganic reinforced composite electrolyte membrane includes a porous polymer support, a hydrophilic polymer impregnation layer, an organic/inorganic polymer impregnation layer, and an upper and lower organic/inorganic polymer layer.

Description

The organic-inorganic composite electrolyte membrane, a method for producing the same, and an application product including the membrane}

The present invention relates to an organic/inorganic reinforced composite electrolyte membrane and a method for manufacturing the same, and more specifically, an organic/inorganic reinforced composite having a low permeability characteristic by generating silica particles while crosslinking an organic polymer and an inorganic polymer impregnated in a porous support. It relates to an electrolyte membrane, a method of manufacturing the same, and an application product including the membrane.

In recent years, there is an urgent need to develop an energy storage device for storing and managing power energy, along with equalizing power load and increasing the proportion of renewable energy generation.

A vanadium redox flow battery, a type of energy storage device, is attracting attention as a large-capacity long-cycle energy storage device because it is easy to increase its capacity because the capacity and output can be individually designed. In the vanadium redox flow battery, the polymer electrolyte membrane is a very important core component that determines the output and long-term performance of the battery and the price of the stack, but the commercially available polymer membrane has high manufacturing cost and high permeability, which hinders the commercialization of the vanadium redox flow battery. It is acting as a factor. Accordingly, there is a need to develop a polymer electrolyte membrane having low transmittance and low cost that can increase the efficiency of an energy storage device.

The separator used for the vanadium redox flow battery is typically commercially sold by DuPont's Nafion, but this is expensive and has high transmittance characteristics, so it was difficult to drive the redox flow battery for a long time.

In order to replace Nafion having such a problem, various types of polymer electrolyte membranes such as hydrocarbon-based polymer membranes and reinforced composite membranes have been developed. Specifically, hydrocarbon-based polymer membranes are typically sulfonated polyether ketone, sulfonated polyether-ether ketone, sulfonated polyether sulfone, sulfonated polysulfone, sulfonated polyphenylene sulfide, sulfonated polyphenylene oxide, and sulfonated polyether. Although mid and the like have been proposed, there is a problem in that the flexibility is low and the chemical stability is weak.

In addition, the reinforced composite membrane has been proposed as a method of preparing a porous support having excellent mechanical strength and durability by introducing an ionomer having excellent ion conductivity, but has a disadvantage in that separation between the porous support and the ionomer occurs.

Therefore, there is a need to develop a technology capable of solving this problem.

Patent Publication No. 10-2018-0003098

The present inventors completed the present invention by developing an organic/inorganic reinforced composite electrolyte membrane having a low permeability characteristic by impregnating an organic/inorganic polymer into a porous support as a result of a number of studies.

Accordingly, an object of the present invention is to ensure excellent dimensional stability through a porous support and at the same time impregnate organic/inorganic polymers with functional groups capable of ion conduction into a low-cost porous support, thereby reducing the cost of a polymer electrolyte membrane. It is to provide a reinforced composite electrolyte film and a method of manufacturing the film.

Another object of the present invention is to create silica particles while crosslinking the organic and inorganic polymers impregnated in a porous support, thereby imparting ionic conductivity and suppressing the permeation of the active material, resulting in significantly improved low-permeability properties than the conventional reinforced composite electrolyte membrane. It is to provide an organic/inorganic reinforced composite electrolyte membrane capable of implementing ionic conductivity and a method of manufacturing the same.

Another object of the present invention is an organic/inorganic reinforced composite electrolyte membrane having excellent binding strength between the porous support and the organic/inorganic polymer layer by first forming a hydrophilic polymer coating layer on a porous support and then impregnating the organic/inorganic polymer, and It is to provide a manufacturing method.

Another object of the present invention is to provide an energy storage device and a water treatment device advantageous for long-term operation by including an organic/inorganic reinforced composite electrolyte membrane having low cost and low transmittance characteristics.

The object of the present invention is not limited to the above-mentioned object, and even if not explicitly mentioned, the object of the invention that one of ordinary skill in the art can recognize from the description of the detailed description of the invention to be described later may naturally be included. .

In order to achieve the object of the present invention described above, the present invention is a porous polymer support; A hydrophilic polymer-impregnated layer formed on all surfaces exposed to the outside of the polymeric support including pores of the polymeric support; An organic/inorganic polymer impregnated layer formed on the hydrophilic polymer impregnated layer; And upper and lower organic/inorganic polymer layers respectively formed on the organic/inorganic polymer impregnated layers formed on the lower and upper surfaces of the porous polymer support. It provides an organic/inorganic reinforced composite electrolyte membrane comprising a.

In a preferred embodiment, the organic/inorganic polymer-impregnated layer and the upper and lower organic/inorganic polymer layers include a crosslinked structure of an inorganic polymer material and an organic polymer material, and nanosilica particles uniformly dispersed within the crosslinked structure. do.

In a preferred embodiment, the organic/inorganic polymer impregnated layer and the upper and lower organic/inorganic polymer layers contain an inorganic polymer material and an organic polymer material in a weight ratio of 0.01:19.99 to 19.99:0.01.

In a preferred embodiment, the inorganic polymer material is from the group consisting of DM-SP, D-SP (Diol Silica Precursor), BD-SP (Bisphenol Dimethylbenzanthracene SP), BDP-SP (Bisphenol Dimethylbenzanthracene Polydimethylsiloxane SP), and combinations thereof. Which one is chosen.

In a preferred embodiment, the organic polymer material is Nafion (Dupon), 3M ionomer (3M), Fumion (Fumatech), Aciplex (Asahi Chemical), Aquivion (Solvay), sulfonated perfluorinated polymer (PFSA, perfluorinated sulfonic acid), polytetrafluoroethylene, polyvinylidene fluoride, polyvinyl fluoride, polyvinylidene fluorocoperfluorinated alkyl vinyl ether, and combinations thereof.

In a preferred embodiment, the porous polymer support is made of polyethylene or polyethylene including hydrophilic silica.

In a preferred embodiment, the porous support includes pores having a diameter in the range of 5 nm to 100 μm.

In a preferred embodiment, the hydrophilic polymer is at least one selected from the group consisting of polydopamine, polyethylene glycol and polyvinyl alcohol.

In addition, the present invention comprises the steps of preparing a porous polymer support; A first impregnation step of impregnating the porous polymer support in a hydrophilic polymer solution to obtain a first impregnation treatment polymer support in which a hydrophilic polymer impregnation layer is formed on all surfaces exposed to the outside including pores of the porous polymer support; A second impregnation step of impregnating the first impregnated polymer support into an organic/inorganic polymer solution to obtain a secondary impregnation treatment polymer support having an organic/inorganic polymer impregnated layer formed on the hydrophilic polymer impregnated layer; A film forming step of obtaining a precursor film having an upper organic/inorganic polymer layer and a lower organic/inorganic polymer layer formed on the upper and lower surfaces of the secondary impregnation-treated polymer support; And pre-treating the precursor film. It provides a method for manufacturing an organic/inorganic enhanced composite electrolyte film including.

In a preferred embodiment, in the second impregnation step, the organic/inorganic polymer solution is prepared by preparing an inorganic polymer solution; Preparing an organic polymer solution; And mixing the inorganic polymer solution and the organic polymer solution in a weight ratio of 0.5:99.5 to 99.5:0.5.

In a preferred embodiment, the inorganic polymer solution or the organic polymer solution contains 1 to 70 parts by weight of the inorganic polymer or organic polymer per 100 parts by weight of the solvent.

In a preferred embodiment, the solvent is an alcohol-based solvent including distilled water, ethanol, isopropanol, and methanol; Dimethyl sulfoxide; N,N-dimethylacetamide, N-methyl-2-pyrillydinone, N,N-dimethylformamide; And combinations thereof.

In a preferred embodiment, the mixing step further comprises the step of mixing the inorganic polymer solution and the organic polymer solution and stirring for several minutes to several days in a reactor maintained at a temperature of 20 to 50 degrees.

In a preferred embodiment, the second impregnation step is performed by impregnating the first impregnated polymer support into an organic/inorganic polymer solution and then maintaining a vacuum state.

In a preferred embodiment, the film forming step includes forming a lower organic/inorganic polymer layer by casting an organic/inorganic polymer solution onto a flat plate; A lower layer forming step of placing the secondary impregnated polymer support on the lower organic/inorganic polymer layer, drying treatment, and peeling from the flat plate to obtain a primary precursor film having a lower organic/inorganic polymer layer; Casting an organic/inorganic polymer solution on a flat plate to form an upper organic/inorganic polymer layer; On the upper organic/inorganic polymer layer, the upper surface of the primary precursor film on which the lower organic/inorganic polymer layer is not formed is brought into contact, dried, and peeled from the flat plate to form upper and lower organic/inorganic polymer layers. And an upper layer forming step of obtaining a shielding sphere film.

In a preferred embodiment, through the drying treatment performed in the lower layer forming step and the upper layer forming step, a crosslinked structure of inorganic and organic polymers and nanosilica particles uniformly dispersed within the crosslinked structure are produced.

In a preferred embodiment, the pretreatment step is performed by immersing the secondary precursor membrane in a basic aqueous solution, immersing it in distilled water, immersing it in an acidic aqueous solution, and then immersing it in distilled water.

In a preferred embodiment, the basic aqueous solution is a 1 to 30% H ₂ O ₂ aqueous solution, and the acidic aqueous solution is a 0.05 to 5M H ₂ SO ₄ aqueous solution.

In addition, the present invention provides a redox flow battery including an organic/inorganic reinforced composite electrolyte membrane or an organic/inorganic reinforced composite electrolyte membrane manufactured by any one of the above-described manufacturing methods.

In addition, the present invention provides a water treatment apparatus including an organic/inorganic reinforced composite electrolyte membrane manufactured by any one of the above-described organic/inorganic reinforced composite electrolyte membranes or any one manufacturing method.

The present invention described above has the following effects.

First, according to the organic/inorganic reinforced composite electrolyte membrane of the present invention and the method of manufacturing the membrane, by impregnating an organic/inorganic polymer into which a functional group capable of ion conduction is introduced into a low-cost porous support while securing excellent dimensional stability through a porous support. The cost of the polymer electrolyte membrane can be reduced.

In addition, according to the organic/inorganic reinforced composite electrolyte membrane and its manufacturing method of the present invention, the organic polymer and the inorganic polymer impregnated in the porous support are crosslinked to generate silica particles to impart ionic conductivity while inhibiting the permeation of active materials. Compared to the reinforced composite electrolyte membrane, it is possible to realize a low transmittance characteristic and ionic conductivity that are significantly improved.

In addition, according to the organic/inorganic reinforced composite electrolyte membrane and its manufacturing method of the present invention, a hydrophilic polymer coating layer is first formed on a porous support and then impregnated with organic/inorganic polymers, so that the adhesion between the porous support and the organic/inorganic polymer layer is excellent. Has.

In addition, the energy storage device and the water treatment device of the present invention include an organic/inorganic reinforced composite electrolyte membrane having characteristics of low cost and low transmittance, thereby being advantageous in long-term operation and excellent in economic efficiency.

These technical effects of the present invention are not limited only to the ranges mentioned above, and even if not explicitly mentioned, the effects of the invention that can be recognized by those of ordinary skill in the art from the description of specific details for the implementation of the invention described later are also Of course it is included.

1 is a graph showing FT-IR results of an organic/inorganic reinforced composite electrolyte membrane according to embodiments of the present invention.
2 is a graph showing a result of measuring the moisture content of an organic/inorganic reinforced composite electrolyte membrane according to embodiments of the present invention.
3 is a graph showing a result of measuring dimensional stability of an organic/inorganic reinforced composite electrolyte membrane according to other embodiments of the present invention.
4 is a graph showing the measurement result of ionic conductivity of an organic/inorganic reinforced composite electrolyte membrane according to embodiments of the present invention.

The terms used in the present invention are only used 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 present application, terms such as "comprise" or "have" are intended to designate the existence of features, numbers, steps, actions, elements, parts, or a combination thereof described in the description of the invention, but one or more other It is to be understood that it does not preclude the presence or addition of features, numbers, steps, actions, components, parts, or combinations thereof.

Terms such as first and second may be used to describe various elements, but the elements should not be limited by the terms. These terms are only used for the purpose of distinguishing one component from another component. For example, without departing from the scope of the present invention, a first component may be referred to as a second component, and similarly, a second component may be referred to as a first component.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. Terms as defined in a commonly used dictionary should be interpreted as having a meaning consistent with the meaning in the context of the related technology, and should not be interpreted as an ideal or excessively formal meaning unless explicitly defined in the present invention. Does not.

In interpreting the constituent elements, it is interpreted as including an error range even if there is no explicit description. In particular, when the terms "about", "substantially" and the like of degree are used, it can be interpreted as being used in or close to that value when manufacturing and material tolerances specific to the stated meaning are presented. .

In the case of a description of a temporal relationship, for example,'after','following','after','before', etc. It includes cases that are not continuous unless' is used.

Hereinafter, the technical configuration of the present invention will be described in detail with reference to the accompanying drawings and preferred embodiments.

However, the present invention is not limited to the embodiments described herein, and the same reference numerals denote the same elements in different forms.

The technical feature of the present invention is that the cost of the polymer electrolyte membrane can be reduced by impregnating an organic/inorganic polymer into which a functional group capable of ion conduction is introduced into a low-cost porous support while securing excellent dimensional stability through a porous support. The organic/inorganic reinforced composite electrolyte is capable of realizing significantly improved low permeability and ionic conductivity compared to existing reinforced composite electrolyte membranes by creating silica particles while crosslinking organic and inorganic polymers to provide ionic conductivity while suppressing the permeation of active materials. In the membrane and its manufacturing method.

Accordingly, the organic/inorganic reinforced composite electrolyte membrane of the present invention comprises a porous polymer support; A hydrophilic polymer-impregnated layer formed on all surfaces exposed to the outside of the polymeric support including pores of the polymeric support; An organic/inorganic polymer impregnated layer formed on the hydrophilic polymer impregnated layer; And upper and lower organic/inorganic polymer layers respectively formed on the organic/inorganic polymer impregnated layers formed on the lower and upper surfaces of the porous polymer support.

Particularly, in the organic/inorganic reinforced composite electrolyte membrane of the present invention, the hydrophilic polymer-impregnated layer provides excellent binding between the porous polymer support and the organic/inorganic polymer, which is an ion transport material, and the organic/inorganic polymer impregnated layer and the upper and lower organic/inorganic Since the silica particles generated when the crosslinked structure is formed by the condensation reaction of the organic and inorganic polymers in the polymer layer are homogeneously distributed, it not only improves the low-permeability characteristics of the organic/inorganic reinforced composite electrolyte membrane, but also secures sufficient ion selectivity. I can.

In the present invention, all known porous polymers may be used as the porous polymer support in the form of a membrane, but may be any one selected from the group consisting of porous polyethylene and porous polyethylene including hydrophilic silica as an embodiment. The porous polymer scaffold may have a number of pores having a diameter in the range of 5 nm to 100 μm.If the pore diameter is less than 5 nm, it is difficult to form an ion conductive channel, and if the pore diameter exceeds 100 μm, it is difficult to control the transmittance. The optimal pore size included in the polymeric support was determined. In addition, the porosity is not particularly limited, but may be in the range of 30 to 80%. That is, if the porosity of the porous polymer support is less than 30%, it is difficult to coat the ion conductive material, and at the same time, the amount of the ion conductive material is small, so the properties of the ion conductivity may decrease. If the porosity exceeds 80%, the porous polymer This is because the mechanical strength of the support itself cannot be maintained, and when the ion conductive material is coated, the mechanical strength, which is an excellent property of the existing reinforced composite membrane, may decrease.

The hydrophilic polymer-impregnated layer is for imparting hydrophilicity to the porous polymer support, and is formed by impregnating the porous polymer support in a hydrophilic polymer solution. All known hydrophilic polymers may be used as the hydrophilic polymer, but as an embodiment, any one or more selected from the group consisting of polydopamine, polyethylene glycol, polyvinyl alcohol, and combinations thereof may be used. Particularly, since an organic/inorganic polymer impregnated layer is formed as an ion transport layer on the hydrophilic polymer impregnated layer formed on the porous polymer support, the hydrophilic polymer impregnation does not require a separate process of substituting a special hydrophilic functional group with an ionic functional group. Due to the layer, the interfacial bonding strength between the porous polymer support and the ion transport layer is very strong, so that the hydration stability can be improved as described later. As an embodiment, since dopamine is not only a hydrophilic material, but also has strong adhesive properties, polydopamine can be used as a hydrophilic polymer.In this case, dopamine chloride is added to distilled water, stirred, and then Tris (hydroxymethyl) aminomethane is added to the stirred solution and stirred. Thus, a hydrophilic polymer solution can be obtained.

The organic/inorganic polymer impregnated layer and the upper and lower organic/inorganic polymer layers are designed to ensure low permeability characteristics by significantly lowering the permeability of other active ions while improving the hydrogen ion conductivity.Inorganic and organic polymers are 0.01:19.99 To 19.99:0.01 may be included in a weight ratio, the set range is experimentally determined, and if the inorganic polymer material is included in excess of the set weight ratio, the transmittance is lowered due to the formed silica particles, but there is a problem in that the hydrogen ion conductivity is poor, and the set weight ratio When the inorganic polymer material was introduced below the value, the ionic conductivity was improved and the transmittance was increased.

In the present invention, all known silane-based polymers may be used as the inorganic polymer material, but as an embodiment, DM-SP, D-SP (Diol Silica Precursor), BD-SP (Bisphenol Dimethylbenzanthracene SP), BDP-SP (Bisphenol Dimethyl benzanthracene Polydimethylsiloxane SP) and combinations thereof may be any one or more selected from the group consisting of, and the weight average molecular weight (Mm) may be 50 ~ 　5000 g/mol. This is because if the weight average molecular weight of the silane-based polymer is less than or exceeds the set range, the time may be lengthened when dissolved in an organic solvent or crosslinking may occur in the polymer, resulting in many difficulties.

The organic polymer material is also not particularly limited as long as it is a polymer capable of ion exchange with cation conductivity or anion conductivity, and all known organic polymers may be used. However, as an embodiment, perfluorine-based polymer materials, especially Nafion (Dupon), 3M Ionomer (3M), Fumion (Fumatech), Aciplex (Asahi Chemical), Aquivion (Solvay), sulfonated perfluorinated polymer (PFSA, perfluorinated sulfonic acid), polytetrafluoroethylene, polyvinylidene fluoride, polyvinyl flow It may be any one or more selected from the group consisting of ide, polyvinylidene fluorcoperfluorinated alkyl vinyl ether, and combinations thereof.

In addition, the method of manufacturing an organic/inorganic reinforced composite electrolyte membrane of the present invention comprises: preparing a porous polymer support; A first impregnation step of impregnating the porous polymer support in a hydrophilic polymer solution to obtain a first impregnation treatment polymer support in which a hydrophilic polymer impregnation layer is formed on all surfaces exposed to the outside including pores of the porous polymer support; A second impregnation step of impregnating the first impregnated polymer support into an organic/inorganic polymer solution to obtain a secondary impregnation treatment polymer support having an organic/inorganic polymer impregnated layer formed on the hydrophilic polymer impregnated layer; A film forming step of obtaining a precursor film having an upper organic/inorganic polymer layer and a lower organic/inorganic polymer layer formed on the upper and lower surfaces of the secondary impregnation-treated polymer support; And pre-treating the precursor film.

In the second impregnation step, the organic/inorganic polymer solution is prepared by preparing an inorganic polymer solution; Preparing an organic polymer solution; And mixing the inorganic polymer solution and the organic polymer solution in a weight ratio of 5:95 to 95:5.

At this time, the steps of preparing the inorganic polymer solution and the organic polymer solution may be performed regardless of the sequence, and the inorganic polymer solution and the organic polymer solution are individually prepared by completely dissolving the inorganic polymer material and the organic polymer material in the same solvent. do. Here, the mixing ratio of the solvent and the inorganic polymer or the organic polymer may be 1 to 70 parts by weight of each polymer based on 100 parts by weight of the solvent. The blending ratio was determined experimentally.If the weight of the polymer is less than 1 part by weight or exceeds 70 parts by weight, the viscosity is too low or high, resulting in poor workability, difficulty in controlling the coating thickness, and difficulty in introducing an ion transport material into the pores of the support. Occurred and the optimum solution concentration was experimentally set.

At this time, the solvent used to dissolve the inorganic polymer material and the organic polymer material can act to induce uniform dispersion of the nano silica formed in the condensation reaction process of the crosslinking process by inducing the mixing of the two polymer solutions easily. have. Specifically, the solvent of the inorganic polymer solution and the organic polymer solution may be an alcohol-based solvent including distilled water, ethanol, isopropanol, and methanol; Dimethyl sulfoxide; It may be any one or more selected from the group consisting of N,N-dimethylacetamide, N-methyl-2-pyrillydinone, N,N-dimethylformamide, and combinations thereof.

The organic/inorganic polymer solution is obtained by preparing a homogeneous solution by mixing the prepared inorganic polymer solution and organic polymer solution in a certain ratio.As an embodiment, the inorganic polymer solution and the organic polymer solution are 0.5 parts by weight to 99.5 parts by weight: The composition of the solution can be formed by mixing at various mixing ratios required in the range of 99.5 parts by weight to 0.5 parts by weight. Meanwhile, the organic/inorganic polymer solution may be stirred for several minutes to several days in a reactor maintained at a temperature of 10 to 50 degrees to prepare a homogeneous phase.

The second impregnation step can be performed by impregnating the first impregnated polymer scaffold into an organic/inorganic polymer solution and then maintaining a vacuum state, in which the organic/inorganic polymer solution can be injected into the pores of the porous polymer scaffold. Is to keep.

The film forming step includes forming a lower organic/inorganic polymer layer by casting an organic/inorganic polymer solution onto a flat plate; A lower layer forming step of placing the secondary impregnated polymer support on the lower organic/inorganic polymer layer, drying treatment, and peeling from the flat plate to obtain a primary precursor film having a lower organic/inorganic polymer layer; Casting an organic/inorganic polymer solution on a flat plate to form an upper organic/inorganic polymer layer; On the upper organic/inorganic polymer layer, the upper surface of the primary precursor film on which the lower organic/inorganic polymer layer is not formed is brought into contact, dried, and peeled from the flat plate to form upper and lower organic/inorganic polymer layers. It may include an upper layer forming step of obtaining a shielding sphere film. In this case, the casting may include all commonly performed casting methods such as coating using a comma coater, spin coating, dip coating, slot die coating, or doctor blade coating, but as an embodiment, coating is performed using a doctor blade. In particular, the lower organic/inorganic polymer layer and the upper organic/inorganic polymer layer may be formed by performing casting using separate plates. In addition, in the lower layer forming step and the upper layer forming step, the drying treatment is carried out in a vacuum state at a temperature of 50 to 70°C. Through this drying treatment, the organic polymer and the inorganic polymer undergo thermal crosslinking reaction, and in the reaction process, silica Particles are generated and may be uniformly distributed in the ion transport layer, that is, the organic/inorganic polymer impregnated layer and the upper and lower organic/inorganic polymer layers.

The pretreatment step is performed by immersing the secondary precursor membrane in a basic aqueous solution, immersing it in distilled water, immersing it in an acidic aqueous solution, and immersing it in distilled water.As an embodiment, the basic aqueous solution is 1 to 30% H ₂ O ₂ aqueous solution, the acidic aqueous solution may be a 0.05 to 5M H ₂ SO ₄ aqueous solution, each process of the pretreatment step may be carried out 30 minutes at 50 ℃.

Therefore, the organic/inorganic reinforced composite electrolyte membrane of the present invention has an ion transport layer formed on the inside and surface of the pores of the porous polymer support, and a number of ionic crosslinks are formed inside the ion transport layer, and silica particles are formed from the inorganic polymer to form ions. The conductivity is excellent at 0.064 S/cm, and the transmittance is lowered to 2.00 x 10-6 cm 2 /min or less. In addition, the organic/inorganic reinforced composite electrolyte membrane exhibits excellent dimensional stability of 2.2% due to the excellent durability of the porous polymer support.

As described above, the organic/inorganic reinforced composite electrolyte membrane of the present invention can exhibit 100 times or more improved ionic conductivity compared to the existing support, and can exhibit dimensional stability improved by 10 times or more compared to the commercial membrane, so that the organic/inorganic reinforcement of the present invention It is possible to secure stable performance of energy storage devices and water treatment devices such as fuel cells including composite electrolyte membranes, water electrolysis and secondary batteries (redox flow cells).

Example 1

1. Step of preparing a porous polymer scaffold

A 150um-thick porous polymer support (PE separator) was prepared with a size of 10cm x 10cm. At this time, the pore size was 33 nm and the porosity was 67%. (BET measurement)

2. First impregnation step

① Hydrophilic polymer solution preparation step

Dopamine chloride was added to distilled water at a concentration of 1.5 g/L and stirred for 30 minutes. Tris(hydroxymethyl)aminomethane was added to the prepared solution at a concentration of 3.75mM, and stirred for 10 minutes to dissolve to prepare a hydrophilic polymer solution.

② Impregnation step

The prepared porous polymer support (PE separator) in the prepared hydrophilic polymer solution was impregnated in a vacuum at room temperature for one day, washed with distilled water, and dried under vacuum at 60° C. to obtain a first impregnated polymer support having a hydrophilic polymer impregnated layer formed thereon.

3. Second impregnation step

① Step of preparing inorganic polymer solution

①-1. Step of synthesizing inorganic polymer

14.8 g of DMBA and 34.8 g of TDI were completely dissolved in 100 mL of DMAC in a reaction flask at 60° C. and reacted for 12 hours, and then 22.1 g of APTES was added and reacted at 50° C. for 8 hours to obtain a nanohybrid alkoxy silane functional precursor.

②-2. Preparing an inorganic polymer solution

The synthesized nanohybrid alkoxy silane functional precursor was obtained through a hydrolysis reaction in HCl aqueous solution of 0.1M concentration to obtain a sol-gel mixture, and then the sol-gel mixture was dispersed in DMAc to obtain a homogeneous D-SP polymer solution.

② Step of preparing organic polymer solution

6 g of 3M ionomer and 24 g of DMAc were stirred in a hot-plate at 60° C. for 12 hours to obtain a 20 wt% organic polymer solution.

③ Mixing step

The prepared inorganic polymer solution and the organic polymer solution were variously mixed in 5 parts by weight to 95 parts by weight: 95 parts by weight to 5 parts by weight, respectively, to prepare a homogeneous solution. Specifically, the mixing ratio of the inorganic polymer solution and the organic polymer solution was 50:50, 25:75, 20:80, 10:90, and stirred at room temperature for 24 hours to prepare a homogeneous organic/inorganic polymer solution.

④ Impregnation step

The prepared organic/inorganic polymer solution is impregnated with the first impregnated porous polymer support in a vacuum at room temperature for one day, and then the organic/inorganic polymer solution is added to the inside of the pores of the first impregnated porous polymer support, and then on the hydrophilic polymer impregnated layer. An organic/inorganic polymer impregnated layer was formed to obtain a secondary impregnation-treated polymer support.

4. Production stage

① Step of forming the lower organic/inorganic polymer layer

The organic/inorganic polymer solution prepared in the second impregnation step was cast on a glass plate at room temperature with a doctor blade to form a lower organic/inorganic polymer layer.

② Lower layer formation stage

The secondary impregnation-treated polymer support was placed on the lower organic/inorganic polymer layer formed on the glass plate, and then dried in an oven at 60° C. in a vacuum state for 24 hours. After that, it was peeled from a glass plate to obtain a primary precursor film having a lower organic/inorganic polymer layer.

③ Upper layer formation stage

In order to form an upper layer on the opposite side of the surface where the lower organic/inorganic polymer layer is formed, an organic/inorganic polymer solution is cast on a new glass plate at room temperature with a doctor blade, and the lower organic/inorganic polymer layer of the primary precursor film is not formed thereon. After raising the upper surface to contact, dry it for 24 hours in a vacuum oven at 60℃. Thereafter, it was peeled from a glass plate to obtain a secondary precursor film having upper and lower organic/inorganic polymer layers.

5. Pre-treatment step

The secondary precursor membrane obtained in the film forming step was immersed in 3% H ₂ O ₂ aqueous solution and then immersed in distilled water, and then immersed in 0.5 MH ₂ SO ₄ aqueous solution and then immersed in distilled water to perform pretreatment. Each process of the pretreatment step was performed at 50° C. for 30 minutes to obtain a prototyped organic/inorganic reinforced composite electrolyte membrane 1.

Example 2

An organic/inorganic reinforced composite electrolyte membrane 2 was obtained by performing the same method as in Example 1 except that the thickness of the porous polymer support was set to 65 μm.

Example 3

15 g of 3M ionomer and 15 g of DMAc were stirred at a hot-plate at 60° C. for 12 hours to obtain an organic/inorganic reinforced composite electrolyte membrane 3 in the same manner as in Example 1, except that 50 wt% of an organic polymer solution was used.

Example 4

15 g of 3M ionomer and 15 g of DMAc were stirred in a hot-plate at 60° C. for 12 hours to obtain an organic/inorganic reinforced composite electrolyte membrane 4 in the same manner as in Example 2, except that 50 wt% of an organic polymer solution was used.

Experimental Example 1

In order to analyze the chemical structure of the organic/inorganic reinforced composite electrolyte films prepared in Examples 1 and 2, comparative analysis was performed by Fourier-transform infrared spectroscopy (FT-IR), and the results are shown in FIG.

1, CH bending vibration (1472 cm ^-1 ) and Si-O stretching (1012 cm ^-1 ) peaks of the PE separator as a support were observed in the organic/inorganic reinforced composite electrolyte membrane. In addition, the ?OH functional group (3400 cm ^-1 ) peak and the C=O functional group (1720 cm ^-1 ) peak derived from the carbonyl group appeared, confirming that the inorganic polymer SP was introduced into the ion transport layer. FCF functional group (1193, 1143 cm ^-1 ) peak, COC functional group (1057 cm ^-1 ) peak and S=O functional group derived from sulfonic acid group (870, 849 cm ^-1 ) peak and SO functional group (766 cm ^-1 ) As the peak appeared, it was confirmed that the organic polymer PFSA was introduced into the ion transport layer.

Experimental Example 2

In order to measure the water uptake and dimensional change of the organic/inorganic reinforced composite electrolyte membranes 1 to 4 prepared in Examples 1 to 4, targeting the organic/inorganic reinforced composite electrolyte membrane and Nafion 212 The moisture content and the dimensional change rate were measured as follows, and the results are shown in FIGS. 2 and 3.

Specifically, the organic/inorganic reinforced composite electrolyte membranes 1 to 4 and the PE separator were dried in an oven at 80°C under vacuum for 24 hours or more, and the mass was measured, and after being immersed in distilled water for 24 hours, the moisture on the surface was removed to increase the weight and The dimensional change was measured, and the moisture content and dimensional change rate were measured through the following equation.

In addition, in Examples 1 to 4, the water content (Water uptake) and the dimensional change according to the content of the organic and inorganic polymers contained in the organic/inorganic polymer solution were measured, and the results are shown in Tables 1 and 2. Shown in.

Mixing ratio
Example Weapon: Organic
50:50 Weapon: Organic
25:75 Weapon: Organic
20:80 Weapon: Organic
10:90 Example 1 46.2 47.2 47.8 48.7 Example 2 42.0 42.7 43.5 44.2 Example 3 46.0 47.3 47.9 49.0 Example 4 42.1 42.9 43.6 44.0

Mixing ratio
Example Weapon: Organic
50:50 Weapon: Organic
25:75 Weapon: Organic
20:80 Weapon: Organic
10:90 Example 1 2.0 2.2 2.3 2.7 Example 2 5.8 7.0 7.3 7.6 Example 3 2.0 2.3 2.5 2.8 Example 4 6.0 6.8 7.3 7.5

As shown in Figs. 2 and 3, which are the results of measuring the moisture content and dimensional change rate of the organic/inorganic reinforced composite electrolyte membranes 1 to 4 and the PE separator, the PE separator has a moisture content of 98 to 106% and a dimensional stability of 1 to 3 %, due to the pores of the PE separator, a very high moisture content was confirmed, and dimensional stability was very excellent. The moisture content of the organic/inorganic reinforced composite electrolyte membranes 1 to 4 is 42 to 50.2% and the dimensional stability is 2 to 8%. By forming the inorganic polymer layer, it was confirmed that the moisture content decreased and the dimensional stability increased. In general, the dimensional stability of Nafion, which is a commercial membrane, is known to be 15 to 20%, but it can be seen that the organic/inorganic reinforced composite electrolyte membranes 1 to 4 of the present invention exhibit superior dimensional stability.

Experimental Example 3

The organic/inorganic reinforced composite electrolyte membranes 1 and 2 prepared in Examples 1 and 2 were immersed in distilled water at room temperature for 24 hours, and then the membrane was placed between the electrodes of the ion conductivity cell, and AC impedance was measured in distilled water. Then, the ionic conductivity of the membrane was measured and the results are shown in FIG. 4.

From Figure 4, which is a result of measuring the ionic conductivity of the organic/inorganic reinforced composite electrolyte membranes 1 and 2 and the PE separator, the organic/inorganic reinforced composite electrolyte membrane of the present invention had higher ionic conductivity than the PE separator. It is predicted that a channel for ion transport was formed through impregnation of an organic/inorganic polymer having an ion-conductive functional group in a PE separator without

Although the present invention has been illustrated and described with a preferred embodiment as described above, it is not limited to the above-described embodiment, and within the scope of the spirit of the present invention, those of ordinary skill in the art Various changes and modifications will be possible.

Claims (20)

Porous polymer support;
A hydrophilic polymer-impregnated layer formed on all surfaces of the polymeric support exposed to the outside, including pores of the polymeric support;
An organic/inorganic polymer impregnated layer formed on the hydrophilic polymer impregnated layer; And
An organic/inorganic reinforced composite electrolyte membrane comprising an upper and lower organic/inorganic polymer layer formed on the organic/inorganic polymer impregnated layer formed on the lower and upper surfaces of the porous polymer support.
The method of claim 1,
The organic/inorganic polymer-impregnated layer and the upper and lower organic/inorganic polymer layers include a crosslinked structure of an inorganic polymer material and an organic polymer material, and nanosilica particles uniformly dispersed within the crosslinked structure. /Inorganic reinforced composite electrolyte membrane.
The method of claim 1,
The organic/inorganic reinforced composite electrolyte membrane, characterized in that the organic/inorganic polymer impregnated layer and the upper and lower organic/inorganic polymer layers contain an inorganic polymer material and an organic polymer material in a weight ratio of 0.01:19.99 to 19.99:0.01.
The method of claim 3,
The inorganic polymer material is any one selected from the group consisting of DM-SP, D-SP (Diol Silica Precursor), BD-SP (Bisphenol Dimethylbenzanthracene SP), BDP-SP (Bisphenol Dimethylbenzanthracene Polydimethylsiloxane SP), and combinations thereof. Organic/inorganic reinforced composite electrolyte membrane characterized by
The method of claim 3,
The organic polymer material is Nafion (DuPont), 3M ionomer (3M), Fumion (Fumatech), Aciplex (Asahi Chemical), Aquivion (Solvay), sulfonated perfluorinated polymer (PFSA, perfluorinated sulfonic acid), polytetra Organic/inorganic reinforced composite electrolyte membrane, characterized in that it is any one selected from the group consisting of fluoroethylene, polyvinylidene fluoride, polyvinyl fluoride, polyvinylidene fluorcoperfluorinated alkyl vinyl ether, and combinations thereof .
The method of claim 1,
The porous polymer support is an organic/inorganic reinforced composite electrolyte membrane, characterized in that made of polyethylene or polyethylene containing hydrophilic silica.
The method of claim 6,
The porous support is an organic/inorganic reinforced composite electrolyte membrane comprising pores having a diameter ranging from 5 nm to 100 μm.
The method of claim 1,
The hydrophilic polymer is an organic/inorganic reinforced composite electrolyte membrane, characterized in that at least one selected from the group consisting of polydopamine, polyethylene glycol, and polyvinyl alcohol.
Preparing a porous polymer support;
A first impregnation step of impregnating the porous polymer support in a hydrophilic polymer solution to obtain a first impregnation treatment polymer support in which a hydrophilic polymer impregnation layer is formed on all surfaces exposed to the outside including pores of the porous polymer support;
A second impregnation step of impregnating the first impregnated polymer support into an organic/inorganic polymer solution to obtain a secondary impregnation treatment polymer support having an organic/inorganic polymer impregnated layer formed on the hydrophilic polymer impregnated layer;
A film forming step of obtaining a precursor film having an upper organic/inorganic polymer layer and a lower organic/inorganic polymer layer formed on the upper and lower surfaces of the secondary impregnation-treated polymer support; And
Pre-treating the precursor film; an organic / inorganic enhanced composite electrolyte film manufacturing method comprising a.
The method of claim 9,
In the second impregnation step, the organic/inorganic polymer solution is prepared by preparing an inorganic polymer solution; Preparing an organic polymer solution; And mixing the inorganic polymer solution and the organic polymer solution in a weight ratio of 0.5:99.5 to 99.5:0.5. 2. A method for producing an organic/inorganic reinforced composite electrolyte membrane comprising:
The method of claim 10,
The method of manufacturing an organic/inorganic reinforced composite electrolyte membrane, wherein the inorganic polymer solution or the organic polymer solution contains 1 to 70 parts by weight of the inorganic polymer or organic polymer per 100 parts by weight of the solvent.
The method of claim 11,
The solvent is an alcohol-based solvent including distilled water, ethanol, isopropanol, and methanol; Dimethyl sulfoxide; N,N-dimethylacetamide, N-methyl-2-pyrillydinone, N,N-dimethylformamide; And organic / inorganic reinforced composite electrolyte film manufacturing method, characterized in that selected from the group consisting of a combination thereof.
The method of claim 10,
The mixing step further comprises the step of mixing the inorganic polymer solution and the organic polymer solution and stirring for a few minutes to several days in a reactor maintained at a temperature of 20 to 50 degrees.Preparation of an organic/inorganic reinforced composite electrolyte membrane Way.
The method of claim 9,
The second impregnation step is performed by impregnating the first impregnation-treated polymer support in an organic/inorganic polymer solution and then maintaining a vacuum state to prepare an organic/inorganic reinforced composite electrolyte membrane.
The method of claim 9,
The film forming step includes forming a lower organic/inorganic polymer layer by casting an organic/inorganic polymer solution onto a flat plate; A lower layer forming step of placing the secondary impregnated polymer support on the lower organic/inorganic polymer layer, drying treatment, and peeling from the flat plate to obtain a primary precursor film having a lower organic/inorganic polymer layer; Casting an organic/inorganic polymer solution on a flat plate to form an upper organic/inorganic polymer layer; On the upper organic/inorganic polymer layer, the upper surface of the primary precursor film on which the lower organic/inorganic polymer layer is not formed is brought into contact, dried, and peeled from the flat plate to form upper and lower organic/inorganic polymer layers. An organic/inorganic reinforced composite electrolyte film manufacturing method comprising a; forming an upper layer for obtaining a shielding body film.
The method of claim 15,
Organic/inorganic reinforced composite, characterized in that through the drying treatment performed in the lower layer forming step and the upper layer forming step, a crosslinked structure of inorganic and organic polymers and nanosilica particles uniformly dispersed within the crosslinked structure are produced. Electrolyte membrane manufacturing method.
The method of claim 9,
The pre-treatment is performed by immersing the secondary precursor membrane in a basic aqueous solution, immersing it in distilled water, immersing it in an acidic aqueous solution, and then immersing it in distilled water to prepare an organic/inorganic reinforced composite electrolyte membrane. Way.
The method of claim 17,
The basic aqueous solution is a 1 to 30% H ₂ O ₂ aqueous solution, and the acidic aqueous solution is an organic/inorganic reinforced composite electrolyte membrane manufacturing method, characterized in that the 0.05 to 5M H ₂ SO ₄ aqueous solution.
A redox flow battery comprising an organic/inorganic reinforced composite electrolyte membrane according to any one of claims 1 to 8 or an organic/inorganic reinforced composite electrolyte membrane manufactured by the manufacturing method of any one of claims 9 to 18.
A water treatment apparatus comprising an organic/inorganic reinforced composite electrolyte membrane according to any one of claims 1 to 8 or an organic/inorganic reinforced composite electrolyte membrane manufactured by the manufacturing method of any one of claims 9 to 18.

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