Separation membrane material, manufacturing method thereof, and separation membrane and water electrolysis apparatus comprising same

Abstract

The present invention relates to separation membrane material, a method for producing same, and a separation membrane and a water electrolysis apparatus comprising same. More specifically, the separation membrane material has excellent electrochemical properties such as ionic conductivity, mechanical properties, and chemical durability, and the membrane that is produced is superbly uniform.

Description

Membrane material, method for manufacturing same, membrane and electrolysis device including same

[0001] The present invention relates to a membrane material, and more specifically, to a membrane material having excellent mechanical properties, electrochemical properties such as ionic conductivity, and chemical durability, and having excellent uniformity of the membrane produced therefrom, a method for producing the same, and a membrane and electrolysis device including the same.

[0002] As the use of fossil fuels has rapidly increased due to recent population growth, the development and supply of alternative energy sources has become an urgent issue due to air pollution caused by byproducts generated from their use and the depletion of fossil fuels themselves.

[0003] Hydrogen energy, one of the alternative energy sources, is the cleanest alternative energy source that can replace fossil fuels. Among the methods of producing hydrogen, the water electrolysis method, which produces hydrogen through electrolysis that splits water into hydrogen and oxygen by supplying electricity to an electrolyte used to ionize water, is considered the most environmentally friendly method of producing hydrogen and is called green hydrogen.

[0004] The production methods of green hydrogen are divided into alkaline electrolysis, cation exchange membrane electrolysis, anion exchange membrane electrolysis, and solid oxide electrolysis depending on the type of electrolyte. The former two electrolysis methods are currently in the commercial technology stage, and the latter two electrolysis methods can be classified as next-generation technology stages.

[0005] Alkaline electrolysis technology is a technology that electrolyzes water using an alkaline electrolyte. It is currently the most commercialized of all electrolysis technologies and has the advantages of good durability and low equipment cost. However, when connected to renewable energy power with irregular output characteristics, the purity of the produced hydrogen decreases and durability and efficiency decrease.

[0006] Cation exchange membrane electrolysis is a type of electrolysis that uses an ion-conducting polymer electrolyte membrane as a separation membrane. It is suitable for connecting renewable energy power sources as it can quickly respond to fluctuations in the power load used, and is in the early stages of commercialization. However, it has the disadvantage of high equipment costs due to the use of precious metal electrodes.

[0007] Solid oxide electrolysis technology is a technology that produces hydrogen by electrolyzing high-temperature steam over 800 degrees Celsius using a solid oxide electrolyte. It is the most efficient technology due to its low power consumption. However, because securing high temperatures is essential, it has limitations in that it must utilize nuclear energy. In addition, there are still technical issues in securing heat-resistant materials for high-temperature operation stability and in assembly.

[0008] In contrast, anion exchange membrane electrolysis technology is a next-generation electrolysis technology that can improve problems that arise when linking renewable energy. It is a technology that combines the operating environment of alkaline electrolysis and the structure of cation exchange membrane electrolysis that uses an ionic polymer electrolyte membrane as a separation membrane.

[0009] In anion exchange membrane electrolysis technology, a unit cell includes an anion exchange membrane, an anode electrode formed on one side of the anion exchange membrane, and a cathode electrode formed on the other side of the anion exchange membrane. A plurality of unit cells are stacked in series to form a water electrolysis stack, and the water electrolysis stack receives an alkaline aqueous solution (KOH or NaOH) from an electrolyte tank, and water is decomposed at the anode to form hydrogen and hydroxide ions (OH - ) is generated. The generated hydroxide ions are transferred through the intermediate anion exchange membrane, and an electrochemical reaction occurs at the cathode in which oxygen is generated from the hydroxide ions. Each of these electrochemical reactions occurs on the catalyst on the gas diffusion layer (GDL), and the anion exchange membrane, as an intermediate electrolyte, exhibits high hydroxide ion conductivity in a wet state and, due to its low gas permeability, plays a role in separating hydrogen and oxygen generated by water electrolysis.

[0010] Unlike cation exchange membrane electrolysis, anion exchange membrane electrolysis (ANEM) technology utilizes inexpensive electrode materials instead of precious metals, and its miniaturization makes it highly economical. Furthermore, it easily adapts to irregular fluctuations in renewable energy loads, making it a promising green hydrogen production method that could replace existing alkaline, cation exchange membrane, and solid oxide electrolysis processes. Nevertheless, anion exchange membrane-based electrochemical systems face challenges in commercialization due to the low electrical performance and durability of their core chemical materials, the anion exchange membrane. Conventional anion exchange membranes suffer from poor mechanical and electrochemical properties, including ionic conductivity, and chemical durability, as well as poor membrane uniformity.

[0011] Accordingly, there is an urgent need to develop a membrane material that has excellent mechanical properties, electrochemical properties such as ionic conductivity, and chemical durability, and at the same time, excellent uniformity of the membrane being manufactured.

[0012] [Prior Art Literature]

[0013] [Patent Document]

[0014] (Patent Document 1) Republic of Korea Patent Publication No. 10-2016-0143103 (Published on December 14, 2016)

[0015] The present invention has been devised to solve the above-described problems, and its purpose is to provide a membrane material having excellent mechanical properties, electrochemical properties such as ionic conductivity, and chemical durability, and having excellent uniformity of the membrane produced therefrom, a method for producing the same, and a membrane and a water electrolysis device including the same.

[0016] In order to solve the above-described problem, the present invention provides a method for producing a membrane material, comprising the steps of: producing a polycarbazole-based anion exchange membrane material precursor by reacting a carbazole-based compound containing a halogen element in its structure, an acetone-based compound containing at least one fluoro group, and a superacid catalyst; and producing a membrane material comprising a polycarbazole-based polymer containing an anion exchange group by reacting the polycarbazole-based anion exchange membrane material precursor with an amine-based compound, wherein the polycarbazole-based polymer containing an anion exchange group has a weight average molecular weight of 120,000 to 500,000.

[0017] According to one embodiment of the present invention, the acetone compound containing at least one fluoro group may include trifluoroacetone.

[0018] Additionally, the acetic acid catalyst may include trifluoromethanesulfonic acid (TFSA).

[0019] Additionally, the amine compound may include trimethylamine.

[0020] In addition, the polycarbazole polymer including the anion exchanger may include a compound represented by the following chemical formula 1.

[0021] [Chemical Formula 1]

[0022]

[0023] In the above chemical formula 1,

[0024] The above R1 may be a substituted or unsubstituted C1 to C10 alkylene group, a substituted or unsubstituted C6 to C20 arylene group, or a substituted or unsubstituted C3 to C20 heteroarylene group, and the above R2 may be a C1 to C10 alkyl group having a substituent substituted with at least one fluoro group, a C6 to C20, or a C3 to C20 heteroaryl group, and the above X - is Cl - , Br - or OH - It may be, and the above n may be a rational number that satisfies the weight average molecular weight of 120,000 to 500,000 of the polycarbazole polymer including the above anion exchanger.

[0025] Additionally, in the step of manufacturing the polycarbazole-based anion exchange membrane material precursor, the superacid catalyst may be used in an amount of 1 to 12 equivalents based on the total amount of the carbazole-based compound containing a halogen element in the structure.

[0026] Additionally, in the step of manufacturing the polycarbazole-based anion exchange membrane material precursor, the superacid catalyst can be added dropwise at a rate of 1 to 100 ml / min.

[0027]

[0028] In addition, the present invention provides a membrane material including a polycarbazole-based polymer including an anion exchanger, wherein the polycarbazole-based polymer including the anion exchanger has a weight average molecular weight of 120,000 to 500,000.

[0029]

[0030] In addition, the present invention provides a separation membrane comprising the above-described separation membrane material.

[0031] According to one embodiment of the present invention, the separation membrane may be any one selected from the group consisting of a single membrane, a reinforced membrane, a composite membrane, and a reinforced composite membrane.

[0032] In addition, the above-mentioned separation membrane may be any one of a separation membrane for water electrolysis, a separation membrane for a redox flow battery, a separation membrane for a fuel cell, a separation membrane for carbon dioxide reduction, a separation membrane for electrochemical ammonia production / decomposition, a separation membrane for electrodialysis (ED), a separation membrane for reverse electrodialysis (RED), and a separation membrane for capacitive deionization (CDI).

[0033] Additionally, the separation membrane may be an anion exchange membrane for water electrolysis (AEMWE).

[0034]

[0035] In addition, the present invention provides a water electrolysis device including the above-described separation membrane.

[0036] The membrane material of the present invention and the membrane material according to the manufacturing method thereof can manufacture a material having a high molecular weight suitable for use as a membrane, and thus has excellent mechanical properties, electrochemical properties such as ionic conductivity, and chemical durability, and at the same time, can exhibit excellent uniformity of the membrane manufactured.

[0037] In addition, a separation membrane including the separation membrane material of the present invention and a water electrolysis device including the same can be configured as a device with improved reliability and performance by being able to operate stably for a longer period of time.

[0038] Figure 1 shows the NMR analysis results of a membrane material precursor according to one embodiment of the present invention.

[0039] Figure 2 shows the NMR analysis results of a membrane material according to one embodiment of the present invention.

[0040] Figure 3 is a graph showing the change in ionic conductivity over time of Example 1, Example 2, and Comparative Example 3 of the present invention and a commercial membrane.

[0041] Hereinafter, embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the invention. The present invention may be implemented in various different forms and is not limited to the embodiments described herein.

[0042]

[0043] A membrane material according to the present invention is manufactured through a manufacturing method including a step of manufacturing a polycarbazole-based anion exchange membrane material precursor by reacting a carbazole-based compound including a halogen element in its structure, an acetone-based compound including at least one fluoro group, and a superacid catalyst, and a step of manufacturing a membrane material including a polycarbazole-based polymer including an anion exchange group by reacting the polycarbazole-based anion exchange membrane material precursor with an amine-based compound. At this time, the polycarbazole-based polymer including the anion exchange group is implemented so as to have a weight average molecular weight of 120,000 to 500,000.

[0044] First, the steps for manufacturing the precursor of the polycarbazole-based anion exchange membrane material are described.

[0045] The step of manufacturing the above polycarbazole-based anion exchange membrane material precursor is performed by reacting a carbazole-based compound including a halogen element in the structure as described above, an acetone-based compound including at least one fluoro group, and a superacid catalyst.

[0046] The carbazole compound containing a halogen element in the above structure may be used without limitation as long as it is a carbazole compound containing a halogen element in a structure that can be commonly used in the art, but it is more advantageous for achieving the purpose of the present invention to use a compound containing a halogen element at the terminal of a hydrocarbon group bonded to a nitrogen atom in the molecular structure of carbazole.

[0047] Additionally, the halogen element may be any one of chlorine (Cl), bromine (Br), and iodine (I), and preferably bromine.

[0048] The acetone compound containing at least one fluoro group may be used without limitation as long as it is an acetone compound containing at least one fluoro group that can be commonly used in the art, but preferably, an acetone compound containing two or more fluoro groups may be used, and more preferably, using trifluoroacetone containing three fluoro groups may be more advantageous in achieving the purpose of the present invention.

[0049] In addition, the superacid catalyst may be used without limitation as long as it is a catalyst exhibiting a super acid that can be commonly used in the art, but preferably, at least one of trifluoromethanesulfonic acid (TFSA) and fluorosulfonic acid may be used, and more preferably, using trifluoromethanesulfonic acid may be more advantageous in achieving the purpose of the present invention.

[0050] In addition, in the step of manufacturing the polycarbazole-based anion exchange membrane material precursor, the superacid catalyst may be used in an amount of 1 to 12 equivalents based on the total amount of the carbazole-based compound containing a halogen element in the structure, and preferably 2 to 11 equivalents. If the superacid catalyst is less than 1 equivalent based on the total amount of the carbazole-based compound containing a halogen element in the structure, the synthesis of the polycarbazole-based anion exchange membrane material precursor may not be possible due to gelation, and if the superacid catalyst is more than 12 equivalents based on the total amount of the carbazole-based compound containing a halogen element in the structure, the synthesis of the polycarbazole-based anion exchange membrane material precursor is possible, but there may be issues with extremely acidic conditions, increased waste, increased raw material costs, and fume safety.

[0051] And, in the step of manufacturing the polycarbazole-based anion exchange membrane material precursor, the superacid catalyst may be added dropwise at a rate of 1 to 100 ml / min, and preferably at a rate of 2 to 50 ml / min. If the superacid catalyst's adding speed is less than 1 ml / min, there may be a problem in that it gels during adding and the reaction cannot proceed any further, and if the adding speed exceeds 100 ml / min, the weight average molecular weight of the produced precursor may be lowered to 100,000 or less, and it may not be usable as a membrane material.

[0052]

[0053] Next, the steps for manufacturing the membrane material are described.

[0054] The step of manufacturing the above-mentioned separation membrane material is performed by reacting the polycarbazole-based anion exchange membrane material precursor with an amine-based compound, as described above.

[0055] The above amine compound may be used without limitation as long as it is an amine compound that can be commonly used in the art, but it is more advantageous to use trimethylamine to achieve the purpose of the present invention.

[0056] A polycarbazole-based polymer including an anion exchange group is produced by reacting the above polycarbazole-based anion exchange membrane material precursor with an amine-based compound, and the polycarbazole-based polymer including the anion exchange group may include a compound represented by the following chemical formula 1.

[0057] [Chemical Formula 1]

[0058]

[0059] In the above chemical formula 1, the R1 may be a substituted or unsubstituted C1 to C10 alkylene group, a substituted or unsubstituted C6 to C20 arylene group, or a substituted or unsubstituted C3 to C20 heteroarylene group, preferably the R1 may be a substituted or unsubstituted C1 to C10 alkylene group, more preferably the R1 may be an unsubstituted C3 to C8 alkylene group, and the R2 may be a substituted or unsubstituted C1 to C10 alkyl group having a substituent substituted with at least one fluoro group, a substituted or unsubstituted C6 to C20 aryl group, or a substituted or unsubstituted C3 to C20 heteroaryl group, preferably the R2 may be a C1 to C10 alkyl group having a substituent substituted with at least one fluoro group, more preferably a C1 to C5 alkyl group having a substituent substituted with at least one fluoro group. It may be an alkyl group, more preferably a C1 to C5 alkyl group having a substituent substituted with at least two fluoro groups, and even more preferably a C1 to C3 alkyl group having a substituent substituted with three fluoro groups, and the X - is Cl - , Br - or OH - It can be, and preferably Br - or OH -It can be, and the above n can be a rational number that satisfies the weight average molecular weight of the polycarbazole polymer including the above anion exchanger of 120,000 to 500,000, preferably 150,000 to 400,000. Most preferably, in the above chemical formula 1, the above R1 can be an unsubstituted alkylene group of C6, and the above R2 can be a trifluoromethyl group, which can be more advantageous in achieving the purpose of the present invention.

[0060]

[0061] Meanwhile, the present invention provides a membrane material comprising a polycarbazole polymer including an anion exchanger.

[0062] The polycarbazole polymer including the anion exchanger may have a weight average molecular weight of 120,000 to 500,000, and preferably, the polycarbazole polymer including the anion exchanger may have a weight average molecular weight of 150,000 to 400,000. When the weight average molecular weight of the polycarbazole polymer including the anion exchanger satisfies the above range, the polycarbazole polymer may exhibit excellent mechanical properties, electrochemical properties such as ionic conductivity, and chemical durability, and at the same time, the uniformity of the manufactured membrane may exhibit an excellent effect.

[0063] In addition, according to one embodiment of the present invention, the polycarbazole-based polymer including the anion exchanger may have a number average molecular weight of 30,000 to 200,000, and preferably, a number average molecular weight of 50,000 to 150,000. When the number average molecular weight of the polycarbazole-based polymer including the anion exchanger satisfies the above range, the polycarbazole-based polymer may exhibit excellent mechanical properties, electrochemical properties such as ionic conductivity, and chemical durability, and at the same time, the uniformity of the manufactured membrane may exhibit an excellent effect.

[0064] Meanwhile, according to one embodiment of the present invention, the polycarbazole polymer including the anion exchanger may have a polydispersity index (PDI) of 1.2 to 9.0, and preferably, the polydispersity index may be 1.5 to 7.0. If the polydispersity index exceeds 9.0, membrane uniformity may deteriorate.

[0065] At this time, the polydispersity can be measured by calculating “weight average molecular weight / number average molecular weight.”

[0066]

[0067] The membrane material of the present invention and its manufacturing method can exhibit excellent mechanical properties, electrochemical properties such as ionic conductivity, and chemical durability, and at the same time, excellent uniformity of the membrane manufactured.

[0068]

[0069] The present invention will be described in more detail through the following examples, but the following examples do not limit the scope of the present invention, and should be interpreted as helping to understand the present invention.

[0070] [Example]

[0071] <Example 1>

[0072] First, 10.0 g of 9-(6-Bromohexyl)-9H-carbazole (JHChem), a carbazole compound containing a halogen element in its structure, was dissolved in MC, and then 10.7 g of trifluoroacetone (TFA, Thermo Fisher), an acetone compound containing at least one fluoro group, was mixed, and 9.5 equivalents of trifluoromethanesulfonic acid (TFSA, Thermo Fisher), an acetic acid catalyst, based on the total amount of the carbazole compound containing a halogen element in the structure, were added dropwise at a rate of 5 ml / min at -5°C or lower, and the mixture was reacted at 5°C for 40 hours. After completion of the reaction, MeOH was used for precipitation, and then the solution was washed three or more times with MeOH until the pH of the washing solution became 4 or higher. The precipitate was dried to prepare a precursor for a polycarbazole-based anion exchange membrane material. The NMR analysis results of the manufactured precursor are shown in Figure 1.

[0073] [ 1 H NMR (400 MHz, CDCl3-d1) d (ppm): 8.19(H a ), 7.30-7.23(H b , H c ), 4.19(H d ), 3.3(H i ), 2.15(H j ), 1.83-1.73(H e , H h ), 3.46-1.36(H f , H g )]

[0074] Then, 10 g of the precursor of the polycarbazole-based anion exchange membrane material was dissolved in NMP, and 6.3 g of trimethylamine (33% solution in ethanol, Thermo Fisher) as an amine compound was added and reacted at 25°C for 16 hours. By degassing using a vacuum pump, a membrane material including a polycarbazole-based polymer including an anion exchange group, which is a compound represented by the following chemical formula 1, was manufactured. The NMR analysis results of the manufactured membrane material are shown in Fig. 2.

[0075] [ 1 H NMR (400 MHz, DMSO-d6) d (ppm): 7.59 (H a ), 7.57(H b ), 7.19(H c ), 4.35(H d ), 3.28(H i ), 3.02(H k ), 2.15(H j ), 1.83-1.73(H e , H h ), 1.42-1.36(H f , H g )]

[0076] [Chemical Formula 1]

[0077]

[0078] In the above chemical formula 1, R1 is an unsubstituted alkylene group of C6, R2 is a trifluoromethyl group, and X is Br - , and the above n is a rational number that satisfies the weight average molecular weight of 276,490 of the polycarbazole polymer including the above anion exchange group.

[0079]

[0080] <Example 2>

[0081] In the above Example 1, except that 2.5 equivalents of trifluoromethanesulfonic acid (TFSA, Thermo Fisher) was used as an acetic acid catalyst based on the total amount of a carbazole compound containing a halogen element in the structure, a separation membrane material including a polycarbazole polymer containing an anion exchange group, which is a compound represented by the above chemical formula 1, was manufactured in the same manner as in Example 1.

[0082]

[0083] <Comparative Example 1>

[0084] In the above Example 1, except that 0.5 equivalents of trifluoromethanesulfonic acid (TFSA, Thermo Fisher) was used as an acetic acid catalyst based on the total amount of the carbazole compound containing a halogen element in the structure, a separation membrane material including a polycarbazole polymer containing an anion exchanger, which is a compound represented by the above chemical formula 1, was manufactured in the same manner as in Example 1. However, in the process of manufacturing the precursor, after trifluoromethanesulfonic acid was added dropwise at a rate of 5 ml / min at -5°C or lower, gelation occurred during the reaction at 5°C for 40 hours, and the reaction was stopped.

[0085]

[0086] <Comparative Example 2>

[0087] In the above Example 1, except that 15 equivalents of trifluoromethanesulfonic acid (TFSA, Thermo Fisher) was used as an acetic acid catalyst based on the total amount of a carbazole-based compound containing a halogen element in the structure, a membrane material including a polycarbazole-based polymer containing an anion exchange group, which is a compound represented by the above chemical formula 1, was manufactured in the same manner as in Example 1. However, during the precipitation process of the precursor of the polycarbazole-based anion exchange membrane material, an excessive amount of fumes were generated, making the operation impossible. In addition, during the washing process of the precipitate generated during the precipitation process, even after several MeOH washes, the pH of the washing solvent was found to be 4 or lower, making it difficult to remove the trifluoromethanesulfonic acid remaining after the completion of the reaction, and the reaction was stopped.

[0088]

[0089] <Comparative Example 3>

[0090] In the above Example 1, except that 9.5 equivalents of trifluoromethanesulfonic acid (TFSA, Thermo Fisher) as an acetic acid catalyst based on the total amount of a carbazole compound containing a halogen element in the structure was added dropwise at a rate of 200 ml / min at -5°C or lower, the same procedure as in Example 1 was performed to manufacture a membrane material including a polycarbazole polymer containing an anion exchange group, which is a compound represented by the above chemical formula 1.

[0091]

[0092] <Experimental Example>

[0093] The following physical properties were evaluated using the membrane material precursors, membrane materials, and membranes formed into films of Examples 1, 2, and Comparative Example 3.

[0094] 1. Molecular weight analysis

[0095] In order to compare the molecular weights of the membrane materials manufactured according to Examples 1, 2, and Comparative Example 3, the molecular weights of the precursors of each polycarbazole-based anion exchange membrane material were analyzed using GPC. GPC used HR 3 and HR 4 columns and Waters' 2414 model as a detector. The manufactured polymers were dissolved in a DMAc solution containing 0.05 M LiBr and injected. The analysis was performed at 25°C and a flow rate of 1.0 mL / min, and the results are summarized in Table 1. (Since polycarbazole-based polymers containing anion exchange groups are ionic substances, molecular weight analysis using GPC is difficult, so the precursors were used for comparative analysis.)

[0096] Number average molecular weight (g / mol) Weight average molecular weight (g / mol) Polydispersity index (PDI) Precursor of Example 1 113,682 243,281 2.14 Precursor of Example 2 116,101 320,439 2.76 Precursor of Comparative Example 3 45,508 73,268 1.61

[0097] As shown in Table 1 above, the precursors of Examples 1 and 2 according to the present invention had a weight average molecular weight that was 3 to 4 times higher than that of Comparative Example 3, and were found to have a molecular weight suitable for use as a separation membrane. This can indicate improved mechanical properties, chemical durability, and stability of the material when applied to a water electrolysis device.

[0098] 2. Mechanical properties evaluation

[0099] A tensile test was performed on the membranes formed into films using the membrane materials manufactured according to Example 1, Example 2 and Comparative Example 3, and the membranes were exposed to hydroxide ions (OH - ) was replaced with UTM and measured, and the results are summarized in Table 2 below.

[0100] Tensile strength (MPa) Example 1 Separator 32 Example 2 Separator 34 Comparative Example 3 Separator 26

[0101] As shown in Table 2 above, it can be seen that the membranes of Examples 1 and 2 of the present invention exhibit a high tensile strength of 30 MPa or more, and compared to Comparative Example 3, it can be seen that they exhibit an improved tensile strength of 20% to 30% or more. This is a comparison of the physical properties of a material with maximized molecular weight and a low molecular weight material, and molecular weight is a very important factor that determines the physical properties of a material, and as the molecular weight is increased, the physical durability of the membrane can be greatly improved.

[0102] 3. Chemical durability evaluation

[0103] For comparison of chemical durability, the ionic conductivity (OH) of the samples was measured every 100 hours while they were stored in an oven at 80℃ for 1,000 hours in a 1M KOH aqueous solution. - ) was measured, and Figure 3 is a graph showing the self-current hydroxide ion conductivity over time.

[0104] Since electrolysis is operated under very harsh conditions, its chemical stability is very important. To accelerate the chemical durability of the developed material, the membranes of Examples 1 and 2 of the present invention and the FAA-3 of Pumatech, a currently sold anion exchange membrane from Germany, were tested in a 1M KOH aqueous solution at 80°C. The ionic conductivity of the samples was measured every 100 hours to compare their chemical durability.

[0105] As shown in Fig. 3, the commercial membrane FAA-3 showed a rapid decrease in performance from the beginning, and after 300 hours, the ionic conductivity was reduced by more than 85% compared to the initial performance. In addition, the membrane of Comparative Example 3 also began to show a decrease in ionic conductivity after 500 hours, and after 800 hours, the ionic conductivity was reduced by more than 50% compared to the initial performance. On the other hand, the membranes of Examples 1 and 2 of the present invention with increased molecular weight maintained the initial ionic conductivity for up to 800 hours, and in particular, the membrane of Example 1 maintained the initial ionic conductivity for up to 1000 hours, showing very excellent chemical durability. From the results of the chemical durability of the membranes of the Examples and Comparative Examples, it can be seen that the membrane of the present invention with increased molecular weight exhibits greatly improved durability, and when introduced into a water electrolysis device, it can exhibit more stable performance.

[0106]

[0107] Although one embodiment of the present invention has been described above, the spirit of the present invention is not limited to the embodiment presented in this specification, and a person skilled in the art who understands the spirit of the present invention will be able to easily propose other embodiments by adding, changing, deleting, or adding components within the scope of the same spirit, but this will also be considered to fall within the spirit of the present invention.

Claims

1. A step of producing a polycarbazole-based anion exchange membrane material precursor by reacting a carbazole-based compound containing a halogen element in the structure, an acetone-based compound containing at least one fluoro group, and a superacid catalyst; and A step of manufacturing a membrane material including a polycarbazole-based polymer including an anion exchange group by reacting the polycarbazole-based anion exchange membrane material precursor with an amine-based compound; comprising; A method for manufacturing a membrane material, wherein the polycarbazole polymer containing the above anion exchanger has a weight average molecular weight of 120,000 to 500,000.

2. In paragraph 1, A method for manufacturing a membrane material, wherein the acetone-based compound containing at least one fluoro group comprises trifluoroacetone.

3. In paragraph 1, The above-mentioned acetic acid catalyst is a method for producing a membrane material including trifluoromethanesulfonic acid (TFSA).

4. In paragraph 1, The above amine compound is a method for manufacturing a membrane material containing trimethylamine.

5. In paragraph 1, A method for manufacturing a membrane material comprising a polycarbazole polymer containing the anion exchanger, wherein the polycarbazole polymer contains a compound represented by the following chemical formula 1: [Chemical Formula 1] In the above chemical formula 1, The above R1 is a substituted or unsubstituted alkylene group having C1 to C10, a substituted or unsubstituted arylene group having C6 to C20, or a substituted or unsubstituted heteroarylene group having C3 to C20, The above R2 is a C1 to C10 alkyl group having a substituent substituted with at least one fluoro group, a C6 to C20 aryl group, or a C3 to C20 heteroaryl group, Above X - is Cl - , Br - Or OH - And, The above n is a rational number that satisfies the weight average molecular weight of 120,000 to 500,000 of the polycarbazole polymer including the above anion exchanger.

6. In paragraph 1, A method for producing a membrane material, wherein in the step of producing the above polycarbazole-based anion exchange membrane material precursor, the superacid catalyst is used in an amount of 1 to 12 equivalents based on the total amount of a carbazole-based compound containing a halogen element in the structure.

7. In paragraph 1, A method for producing a membrane material, wherein in the step of producing the above polycarbazole-based anion exchange membrane material precursor, the acetic acid catalyst is added dropwise at a rate of 1 to 100 ml / min.

8. Contains a polycarbazole polymer containing an anion exchanger, The polycarbazole polymer containing the above anion exchanger is a membrane material having a weight average molecular weight of 120,000 to 500,000.

9. A separation membrane comprising a separation membrane material according to Article 8.

10. In paragraph 9, The above separation membrane is any one membrane selected from the group consisting of a single membrane, a reinforced membrane, a composite membrane, and a reinforced composite membrane.

11. In paragraph 9, the separation membrane, A membrane, any one of a membrane for electrolysis, a membrane for a redox flow battery, a membrane for a fuel cell, a membrane for carbon dioxide reduction, a membrane for electrochemical ammonia production / decomposition, a membrane for electrodialysis (ED), a membrane for reverse electrodialysis (RED), and a membrane for capacitive deionization (CDI).

12. In paragraph 9, The above membrane is an anion exchange membrane for water electrolysis (AEMWE).

13. A water electrolysis device comprising a separation membrane according to any one of clauses 9, 10 and 12.

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