Novel Branched Poly(arylpiperidinium) Copolymer Ionomer, Anion Exchange Membrane, and Method for Producing the Same

Abstract

The present invention relates to a poly(arylpiperidinium) copolymer ionomer in which a branched piperidinium group is introduced into a repeating unit while having no aryl ether bond in the polymer backbone, which has excellent chemical stability, excellent mechanical properties while having a high molecular weight, a low expansion rate, high dimensional stability and ionic conductivity, and a limited phenyl adsorption effect. Further, an anion exchange membrane produced from the above branched poly(arylpiperidinium) copolymer ionomer can operate even under low humidity conditions and has excellent water management ability, and thus can be applied to membranes and binders for alkaline fuel cells, water electrolysis devices, carbon dioxide reduction, vanadium redox flow batteries, or metal-air batteries.

Description

Technical Field

[0001] The present invention relates to a novel branched poly(arylpiperidinium) copolymer ionomer, an anion exchange membrane, and a method for producing the same. More specifically, the present invention relates to a technique for synthesizing a poly(arylpiperidinium) copolymer ionomer in which a branched piperidinium group is introduced into a repeating unit while having no aryl ether bond in the polymer backbone, and then producing an anion exchange membrane and applying it to an alkaline fuel cell and a water electrolysis device.

Background Art

[0002] Hitherto, polymer electrolyte membrane fuel cells (PEMFCs) have been extensively studied because they have relatively high current densities and are environmentally friendly. In particular, perfluorinated carbon-based proton exchange membranes typified by Nafion are mainly used as polymer electrolyte membranes. However, since the Nafion membrane requires the use of a platinum-based noble metal catalyst due to its low oxygen reduction reaction (ORR), its price is very high and its glass transition temperature is low. Therefore, research for replacing Nafion, including the development of aromatic hydrocarbon-based polymer electrolyte membranes, has been actively conducted.

[0003] Among such research, alkaline membrane fuel cells (AMFCs) and water electrolysis using anion exchange membranes can use inexpensive non-noble metals such as nickel and manganese as electrode catalysts instead of platinum, and are known to have excellent performance and remarkable price competitiveness, and continuous research has been conducted. However, research for improving the durability of alkaline membrane fuel cells is desired due to the problem of low long-term stability caused by the decomposition behavior of hydroxyl radicals and ions during operation.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Summary of the Invention

Problems to be Solved by the Invention

[0005] As an anion exchange membrane for application to an alkaline membrane fuel cell, a synthesis method in which a benzyltrimethylammonium group is introduced into an aryl ether-based aromatic polymer structure such as polysulfone (PSF), polyphenyl ether (PPO), or polyether ether ketone (PEEK) is known. This synthesis method has advantages such as improving the solubility of the polymer by forming repeating units having aryl ether (C-O) bonds along the polymer main chain. However, on the other hand, due to the aryl ether bonds in the polymer main chain, there is a problem that the hydroxyl radical decomposition behavior of the electrolyte membrane occurs during the operation of the fuel cell, and the long-term stability decreases. Therefore, preventing the decomposition of the polymer main chain has become an issue to be solved in improving the durability of the alkaline membrane fuel cell.

[0006] In addition, ordinary anion exchange membranes have limited chemical stability (less than 500 hours in 1M NaOH solution at 80°C) and mechanical properties (tensile strength less than 30 Mpa). Therefore, in a fuel cell applying this, the power density is low (0.1~0.5W cm -2 ), and there is a disadvantage that the durability is also low. In addition, when used as a binder due to the adsorption effect of the high phenyl structure, there is a problem that the formation of the three-phase interface is restricted and the fuel efficiency decreases.

[0007] In addition, the water permeation characteristics of anion exchange polymers are very important for water management in anion exchange membrane fuel cells. While water may accumulate at the positive electrode due to electrochemical water generation, the negative electrode is prone to drying due to water consumption. Therefore, in the case of polymers with high water content and swelling ratio, the mass transfer resistance increases while the electrochemical stability is inhibited, which has a great impact on durability.

[0008] On the other hand, there has not yet been a synthesis of poly(arylpiperidinium) copolymer ionomers in which a piperidinium group containing a branched moeity is introduced into the repeating unit while there is no aryl ether bond in the polymer backbone. Also, there is no specific knowledge about the technology of applying this to membranes and binders for alkaline fuel cells or the field of water electrolysis.

[0009] Therefore, as a result of repeated research to expand the application fields of aromatic polymer ion exchange membranes with excellent thermal, chemical stability and mechanical properties, the present inventors attempted to solve problems such as low molecular weight, ionic conductivity, water content, mechanical properties, power density, and durability of conventional anion exchange polymers by including a piperidinium group containing a branched moeity in the anion exchange polymer repeating unit. That is, the inventors synthesized a poly(arylpiperidinium) copolymer ionomer in which a piperidinium group containing a branched moeity was introduced while there was no aryl ether bond in the polymer backbone, and then discovered that an anion exchange membrane produced therefrom can be applied to membranes and binders for alkaline fuel cells, water electrolysis devices, carbon dioxide reduction, vanadium redox flow batteries, or metal-air batteries, etc., and thus completed the present invention.

[0010] The present invention has been made in view of the above problems, and a first object of the present invention is to provide a novel branched poly(arylpiperidinium) copolymer ionomer having excellent chemical stability, excellent mechanical properties while having a high molecular weight, a low expansion rate, high dimensional stability and ionic conductivity, and a limited phenyl adsorption effect, and a method for producing the same.

[0011] Another object of the present invention is to produce an anion exchange membrane from the above novel branched poly(arylpiperidinium) copolymer ionomer, so that it can operate even under low humidity conditions, and is excellent in water management ability, for use in membranes and binders for alkaline fuel cells, water electrolyzers, carbon dioxide reduction, vanadium redox flow batteries or metal-air batteries, etc.

Means for Solving the Problems

[0012] In order to solve the above problems, the present invention provides a branched poly(arylpiperidinium) copolymer ionomer having a repeating unit represented by the following Chemical Formula 1 (Formula 1).

Chemical Formula

Chemical Formula

Chemical Formula

[0013] Further, the present invention provides, as monomers, (a) one or more selected from compounds represented by the following Structural Formula (Formula 4),

Chemical Formula

[0014] The present invention also provides an anion exchange membrane containing the branched poly(arylpiperidinium) copolymer ionomer.

[0015] The present invention also provides (i) a step of dissolving the branched poly(arylpiperidinium) copolymer ionomer in an organic solvent to form a polymer solution, (ii) Casting and drying the polymer solution on a glass plate to obtain a membrane, (iii) Treating the obtained membrane with 1M NaHCO 3 or 1M NaOH, and then washing and drying several times with ultrapure water, Provided is a method for producing an anion exchange membrane including the above.

[0016] The present invention also provides a binder for an alkaline fuel cell containing the branched poly(arylpiperidinium) copolymer ionomer.

[0017] The present invention also provides an alkaline fuel cell including the anion exchange membrane.

[0018] The present invention also provides a water electrolysis device including the anion exchange membrane.

[0019] The present invention also provides a carbon dioxide reduction device including the anion exchange membrane.

[0020] The present invention also provides a vanadium redox flow battery including the anion exchange membrane.

[0021] The present invention also provides a metal-air battery including the anion exchange membrane.

Advantages of the Invention

[0022] The novel branched poly(arylpiperidinium) copolymer ionomer according to the present invention has excellent chemical stability, excellent mechanical properties despite its high molecular weight, low swelling ratio, high dimensional stability and ionic conductivity, and a limited phenyl adsorption effect.

[0023] In addition, the anion exchange membrane produced from the above-mentioned branched poly(arylpiperidinium) copolymer ionomer can operate even under low humidity conditions and has excellent water management ability, so it can be applied to membranes and binders for alkaline fuel cells, water electrolysis devices, carbon dioxide reduction, vanadium redox flow batteries, or metal-air batteries.

Brief Description of the Drawings

[0024]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Mode for Carrying Out the Invention

[0025] Hereinafter, the novel branched poly(arylpiperidinium) copolymer ionomer, anion exchange membrane, and method for manufacturing the same according to the present invention will be described in detail.

[0026] The present invention provides a branched poly(arylpiperidinium) copolymer ionomer having a repeating unit represented by the following Chemical Formula 1 (Formula 1).

Chemical Formula

[0027] In the above Chemical Formula 1, Aryl monomers are one or more selected from the compounds represented by the following Structural Formula (Formula 2).

Chemical Formula

[0028] The Branching agent is any one selected from the compounds represented by the following Structural Formula (Formula 3).

Chemical Formula

[0029] As can be seen in the above Chemical Formula 1 (Formula 1), the branched moiety-containing poly(arylpiperidinium) copolymer ionomer according to the present invention increases the free volume of the polymer by including a branched moiety, and improves the mass transfer ability of the catalyst layer of the alkaline fuel cell. In addition, the high water retention capability enables stable operation under low relative humidity conditions, reduces the adsorption ability with the catalyst surface, contributes to the improvement of the fuel cell performance by activating the electrode, and enhances the safety of the entire system.

[0030] In addition, the above-mentioned branched moiety-containing poly(arylpiperidinium) copolymer ionomer basically does not contain an aryl ether group in the polymer skeleton, and by using a stable N-heterocyclic ammonium group, it not only has excellent chemical stability, but also has a higher molecular weight, durability and excellent mechanical properties compared to linear polymers.

[0031] In addition, the present invention relates to (I) as monomers, (a) one or more selected from the compounds represented by the following structural formula (Formula 4),

Chemical Formula

Chemical Formula

[0032] At this time, the organic solvent in the above step (I) is a halogen-based solvent, and may be one or more selected from the group consisting of dichloromethane, chloroform, dichloroethane, dibromomethane, and tetrachloroethane, and dichloromethane is preferably used.

[0033] Further, the strong acid catalyst in the above step (II) may be trifluoroacetic acid, trifluoromethanesulfonic acid, pentafluoroethanesulfonic acid, heptafluoro-1-propanesulfonic acid, perfluoropropionic acid, heptafluorobutyric acid, or a mixture thereof, and a mixture of trifluoroacetic acid / trifluoromethanesulfonic acid is preferably used.

[0034] Further, the organic solvent in the above step (IV) may be N-methylpyrrolidone, dimethylacetamide, dimethyl sulfoxide, or dimethylformamide.

[0035] Further, in the above step (IV), the polymer is reacted with a halomethane to form a quaternary piperidinium salt. The halomethane may be fluoromethane, chloromethane, bromomethane, or iodomethane, and iodomethane is preferably used.

[0036] The present invention also provides an anion exchange membrane containing the above branched poly(arylpiperidinium) copolymer ionomer.

[0037] The anion exchange membrane according to the present invention is excellent in chemical stability due to the structure of the copolymer ionomer having an N-heteroammonium group while having no aryl ether bond in the polymer backbone. Moreover, due to the structure in which branches are introduced, the molecular weight is high, and in addition to excellent dimensional stability and mechanical properties, it has a unique effect of suppressing the swelling rate while having high ionic conductivity.

[0038] Further, the present invention includes: (i) a step of dissolving the above-mentioned branch-containing poly(arylpiperidinium) copolymer ionomer in an organic solvent to form a polymer solution; (ii) a step of casting and drying the above-mentioned polymer solution on a glass plate to obtain a film; and (iii) treating the obtained film with 1M NaHCO 3 or 1M NaOH, and then washing with ultrapure water several times and drying, and provides a method for producing an anion exchange membrane.

[0039] At this time, the organic solvent in the above step (i) may be N-methylpyrrolidone, dimethylacetamide, dimethyl sulfoxide, or dimethylformamide.

[0040] Further, the concentration of the above polymer solution is preferably 2 to 30% by weight, and more preferably 3.0 to 5.0% by weight. If the concentration of the polymer solution is less than 2% by weight, the film-forming ability may decrease. If it exceeds 30% by weight, the viscosity becomes too high, and the physical properties of the film may deteriorate after film formation.

[0041] Further, for the drying in the above step (ii), it is preferable to gradually remove the organic solvent in an oven at 80 to 90 °C for 24 hours and then completely remove the organic solvent by heating in a vacuum oven at 120 to 150 °C for 12 hours.

[0042] Next, by treating the branch-containing poly(arylpiperidinium) copolymer ionomer film obtained in the above steps (i) to (ii) with 1M NaHCO 3 or 1M NaOH, an anion exchange membrane in which the halide form (such as I-form) of the branch-containing poly(arylpiperidinium) copolymer ionomer is converted into the HCO 3- or OH - form can be produced.

[0043] Further, the present invention provides a binder for an alkaline fuel cell containing the above-mentioned branch-containing poly(arylpiperidinium) copolymer ionomer.

[0044] Furthermore, the present invention provides an alkaline fuel cell including the above anion exchange membrane.

[0045] Furthermore, the present invention provides a water electrolysis device including the above anion exchange membrane.

[0046] Furthermore, the present invention provides a carbon dioxide reduction device including the above anion exchange membrane.

[0047] Furthermore, the present invention provides a vanadium redox flow battery including the above anion exchange membrane.

[0048] Furthermore, the present invention provides a metal-air battery including the above anion exchange membrane.

[0049] Hereinafter, examples and comparative examples according to the present invention will be specifically described together with the accompanying drawings.

[0050] <Examples 1 and 2: Production of Triphenylene-branched Poly(arylpiperidinium) Copolymer Ionomer> As monomers, diphenylethane [DP, 6.75 mmol (1.23 g)], p-terphenyl [TP, 20.25 mmol (4.663 g)], triphenylene [Trip, 1 mmol (0.254 g)], and 1-methyl-4-piperidone [MP, 34.2 mmol (3.87 g)] were charged into a 100 mL reactor. Then, dichloromethane (DCM, 24 mL) was added and the monomers were dissolved with stirring to form a solution. After cooling the temperature of the above solution to -1 °C, a mixture of trifluoroacetic acid (TFA, 3.6 mL) and trifluoromethanesulfonic acid (TFSA, 30 mL) was gradually added to the above solution, stirred, and reacted for 2 hours to obtain a viscous solution. The above viscous solution was poured into distilled water for precipitation, washed several times with deionized water, and dried in an oven at 80 °C for 24 hours to produce a solid triphenylene-branched poly(diphenyl-co-terphenyl N-methylpiperidine) copolymer (yield 92%), which was named b-PDTM-Trip-3.5.

[0051] Next, after dissolving the above-prepared b-PDTM-Trip-3.5 (20 mmol) in dimethyl sulfoxide (200 mL) to obtain a polymer solution, K 2 CO 3 (6.9 g, 50 mmol) and iodomethane [MeI, 60 mmol (8.46 g)] were added, and the reaction was carried out at room temperature in the dark for 24 hours to form a quaternary piperidinium salt. Next, the polymer solution was precipitated in 500 mL of ethyl acetate, filtered, washed several times with deionized water, and completely dried in an 80 °C convection oven to produce a solid tribenzenyl-containing poly(diphenyl-co-terphenyl N,N-dimethylpiperidinium) copolymer ionomer (yield 83%), which was named b-PDTP-Trip-3.5, and its synthetic route is shown in the following Scheme 1 (Chemical Formula 6) by a reaction formula (Example 1).

[0052] [Chemical Formula] [Scheme 1. Synthetic route of tribenzenyl-containing poly(diphenyl-co-terphenyl N,N-dimethylpiperidinium) copolymer ionomer]

[0053] Also, in the reaction formula of the synthetic route shown in Scheme 1 above, a tribenzenyl-containing poly(diphenyl-co-terphenyl N,N-dimethylpiperidinium) copolymer and its ionomer with the molar fraction X (%) of tribenzenyl adjusted to 5% were prepared in the same manner as in Example 1, and these were named b-PDTM-Trip-5 and b-PDTP-Trip-5, respectively (Example 2).

[0054] [Examples 3 and 4: Preparation of tribenzenyl-containing poly(arylpiperidinium) copolymer ionomers] Except for using 9,9'-dimethylfluorene and biphenyl as monomers instead of the diphenylethane and p-terphenyl of Examples 1 and 2, the triphenylene-branched poly(fluorene-co-biphenyl N,N-dimethylpiperidinium) copolymer and its ionomer were produced in the same manner as in Examples 1 and 2, and these were named b-PFBM-Trip-3.5, b-PFBP-Trip-3.5 (Example 3), and b-PFBM-Trip-5, b-PFBP-Trip-5 (Example 4), respectively. The synthetic route thereof was shown by a reaction formula in the following Scheme 2 (Chemical Formula 6). (Using p-terphenyl of Example 1 instead of biphenyl, the triphenylene-branched poly(fluorene-co-terphenyl N,N-dimethylpiperidinium) copolymer and its ionomer as in Example 4 were also produced, and these were named b-PFTM-Trip-5 and b-PFTP-Trip-5, respectively.)

[0055] [Chemical Formula] [Scheme 2. Synthetic Route of Triphenylene-Branched Poly(fluorene-co-biphenyl N,N-dimethylpiperidinium) Copolymer Ionomer]

[0056] [Examples 5 and 6: Production of 1,3,5-Triphenylbenzene-Branched Poly(arylpiperidinium) Copolymer Ionomer] Except for using 1,3,5-triphenylbenzene as the monomer instead of triphenylene of Example 1, the 1,3,5-triphenylbenzene-branched poly(diphenyl-co-terphenyl N,N-dimethylpiperidinium) copolymer and its ionomer were produced in the same manner as in Example 1, and these were named b-PDTM-Tpb-3.5, b-PDTP-Tpb-3.5 (Example 5), and b-PDTM-Tpb-5, b-PDTP-Tpb-5 (Example 6), respectively. The synthetic route thereof was shown by a reaction formula in the following Scheme 3 (Chemical Formula 7).

[0057] [Chemical Formula] [Synthesis Route of Poly(diphenyl - co - terphenyl N,N - dimethylpiperidinium) Copolymer Ionomer Containing 1,3,5 - Triphenylbenzene Branches]

[0058] [Examples 7 and 8: Preparation of Poly(arylpiperidinium) Copolymer Ionomer Containing 1,3,5 - Triphenylbenzene Branches] Except for using 1,3,5 - triphenylbenzene instead of tripcene in Example 3 as the monomer, poly(fluorene - co - biphenyl N,N - dimethylpiperidinium) copolymer and its ionomer containing 1,3,5 - triphenylbenzene branches were prepared in the same manner as in Example 3, and were named b - PFBM - Tpb - 3.5, b - PFBP - Tpb - 3.5 (Example 7), and b - PFBM - Tpb - 5, b - PFBP - Tpb - 5 (Example 8) respectively. The synthesis route is shown in reaction formula in Scheme 4 (Chemical Formula 8) below.

[0059] [Chemical Formula] [Scheme 4. Synthesis Route of Poly(fluorene - co - biphenyl N,N - dimethylpiperidinium) Copolymer Ionomer Containing 1,3,5 - Triphenylbenzene Branches]

[0060] [Example 9: Preparation of Anion Exchange Membrane from Poly(arylpiperidinium) Copolymer Ionomer Containing Branches] The poly(arylpiperidinium) copolymer ionomer (1.7 g) prepared from the above Examples 1 - 8 was dissolved in dimethyl sulfoxide to form a polymer solution with a concentration of 4 wt%. Then, the above polymer solution was filtered through a 0.45 μm PTFE filter, and the transparent solution was cast onto a 21×24 cm glass plate. The casting solution was dried in an oven at 90 °C for 24 hours to gradually remove the solvent, and then heated in a vacuum oven at 140 °C for 12 hours to completely remove the solvent, thereby obtaining a membrane (I - form, thickness 25 ± 5 μm).

[0061] The above-mentioned I-shaped membrane was immersed in a 1 M aqueous NaOH solution for 24 hours to convert the counterions to OH-, and then washed several times with ultrapure water and dried to produce an anion exchange membrane. (The naming of the obtained anion exchange membrane samples was the same as that for the branched poly(arylpiperidinium) copolymer ionomers prepared in Examples 1 to 8.)

[0062] <Comparative Example 1: Preparation of Anion Exchange Membrane from Poly(arylpiperidinium) Copolymer Ionomer without Branched Moiety> An anion exchange membrane without a branched moiety was prepared by forming a film from the poly(diphenyl-co-terphenyl N,N-dimethylpiperidinium) copolymer ionomer obtained in the same manner as in Example 1 except that tripcene was not used as a monomer, in the same manner as in Example 9, and this was named PDTP.

[0063] <Comparative Example 2: Preparation of Anion Exchange Membrane from Poly(arylpiperidinium) Copolymer Ionomer without Branched Moiety> An anion exchange membrane without a branched moiety was prepared by forming a film from the poly(fluorene-co-biphenyl N,N-dimethylpiperidinium) copolymer ionomer obtained in the same manner as in Example 3 except that tripcene was not used as a monomer, in the same manner as in Example 9, and this was named PFBP.

[0064] <Test Example> Test data such as the mechanical properties, water content, swelling ratio, and fuel cell performance of the anion exchange membranes prepared in the examples and comparative examples of the present invention were measured and evaluated by the method described in the prior application Korean Patent Publication No. 10-2021-0071810 by the inventors of the present invention.

[0065] Figure 1 shows the nuclear magnetic resonance of b-PDTM-Trip-x (x = 3.5, 5) and b-PFBM-Trip-x (x = 3.5, 5) prepared from Examples 1 to 4 of the present invention. 1The (¹H NMR) spectra are shown. Figure 2 shows the nuclear magnetic resonance ((¹H NMR)) spectra of b-PDTM-Tpb-3.5 and b-PDTP-Tpb-3.5 produced from Example 5 of the present invention, and b-PFBM-Tpb-3.5 and b-PFBP-Tpb-3.5 produced from Example 7. 1 The characteristic peak of triphenylene was observed at 5.49 ppm and that of 1,3,5-triphenylbenzene was observed at 7.8 ppm, respectively, confirming the synthesis of the branched poly(arylpiperidinium) copolymer.

[0066] Also, Figure 3 shows the mechanical properties of some of the anion exchange membranes (I-form) produced from Example 9 of the present invention (produced from the copolymer ionomers obtained in Examples 1 to 8), and the anion exchange membranes produced from Comparative Examples 1 and 2.

[0067] Due to the structure containing branches, increased molecular weight, and entangled structure according to the examples of the present invention, higher tensile strength and elongation are shown compared to the comparative examples without branches, and it can be seen that the increased mechanical strength contributes to the improvement of cell performance and durability.

[0068] Also, Figure 4 shows the swelling ratio and water uptake of some of the anion exchange membranes (OH-form) produced from Example 9 of the present invention (produced from the copolymer ionomers obtained in Examples 1 to 8), and the anion exchange membranes produced from Comparative Examples 1 and 2.

[0069] It can be seen that the copolymer ionomer membrane containing branches according to the examples of the present invention exhibits a lower swelling ratio and a higher water content compared to the conventional copolymer ionomer membrane without branches due to its high molecular weight, supramolecular chain-threading, interlocking reaction, π-stacking interaction, high ion exchange capacity (IEC), and improved free volume.

[0070] Generally, an increase in water content and ionic conductivity leads to an increase in the swelling ratio. However, for the copolymer ionomer membrane containing the branch portion according to the present invention, although the water content is high, the swelling ratio is suppressed by the branch structure, and desired physical properties can be obtained.

[0071] That is, due to the structure containing the branch portion of the present invention, a high water content, improved dimensional stability, and mechanical strength of the anion exchange membrane can be obtained, and the dilemma between ionic conductivity and swelling ratio can be solved.

[0072] Further, FIG. 5 shows the hydrogen permeability of a part of the anion exchange membrane manufactured from Example 9 of the present invention (manufactured from the copolymer ionomers obtained in Examples 1 to 8) and the anion exchange membrane manufactured in Comparative Example 1.

[0073] Due to the improved free volume of the robust branch structure according to the present invention, the hydrogen permeability of the ionomer used in the catalyst layer is improved. Such improved hydrogen permeability can reduce the mass transfer resistance of reactants during the electrochemical reaction and assist in the formation of the three-phase interface of the catalyst layer.

[0074] Further, FIG. 6 shows the fuel cell performance when the anode and cathode binders of b-PDTP-Trip-5 among the anion exchange membranes manufactured from Example 9 of the present invention are separated [binder A / C b-PFBP-Trip-3.5 according to Example 3, binder A / C b-PFBP-Trip-5 according to Example 4]. FIG. 7 shows the fuel cell performance when the anode and cathode binder b-PFBP-Trip-5 according to Example 4 of the present invention is applied to b-PDTP-Trip-3.5 and b-PDTP-Trip-5 among the anion exchange membranes manufactured from Example 9 of the present invention. According to these, at high relative humidity, H 2- O 2 @ 80 ° C, 1.3 bar, it shows excellent performance of 2.5 W cm -2 . This is performance similar to the initial (pristine) structure.

[0075] Further, FIG. 8 shows the fuel cell performance when the negative and positive binders of b-PDTP-Trip-3.5 among the anion exchange membranes manufactured from Example 9 of the present invention are separated under low humidity conditions [binder A / C b-PFBP-Trip-3.5 according to Example 3, binder A / C b-PFBP-Trip-5 according to Example 4]. FIG. 9 shows the fuel cell performance when the negative and positive binder b-PFBP-Trip-3.5 according to Example 3 of the present invention is applied to b-PDTP-Trip-3.5 and b-PDTP-Trip-5 among the anion exchange membranes manufactured in Example 9.

[0076] Low relative humidity, H 2- O 2 @80 °C and 1.3 bar also shows excellent performance of 1.6 W cm -2 . This can be analyzed as showing excellent fuel cell performance even at low humidity and low flow rates due to the improved free volume, high ionic conductivity, high water content, and improved three-phase interface of the catalyst layer of the dendritic structure ionomer according to the present invention.

[0077] Further, FIG. 10 shows the water electrolysis performance of the anion exchange membrane depending on the content of the negative and positive ionomers when b-PDTP-Trip-5 among the anion exchange membranes manufactured from Example 9 of the present invention is used. According to this, the above b-PDTP-Trip-5 anion exchange membrane has the highest performance among the known performances due to its high ionic conductivity, and achieves a current density of 16 A cm -2 at 80 °C and 2.0 V.

[0078] Further, from FIG. 11, when b-PDTP-Trip-5 among the anion exchange membranes manufactured from Example 9 of the present invention is used (membrane thickness: 50 μm), it can be confirmed that it shows long-term stability of 1.5 A cm -2 at 60 °C for 110 hours.

Claims

1. A branched poly(arylpiperidinium) copolymer ionomer having repeating units represented by the following chemical formula. 【Chemical 1】 Here, in the said chemical formula, the Aryl monomers are one or more selected from the compounds represented by the following structural formula (Formula 2), 【Chemical Formula 2】 and the Branching agent is any one selected from the compounds represented by the following structural formula (Formula 3). 【Chemical Formula 3】

2. (I) As monomers, (a) one or more selected from the compounds represented by the following structural formula (Formula 4), 【Chemical Formula 4】 (b) one or more selected from the compounds represented by the following structural formula (Formula 5), and 【Chemical Formula 5】 (c) dissolving 1-methyl-4-piperidone in an organic solvent to form a solution; (II) gradually adding a strong acid catalyst to the said solution, stirring and reacting to obtain a viscous solution; (III) precipitating, washing and drying the said viscous solution to obtain a solid polymer; (IV) adding and reacting K ２ CO ３ and an excess amount of halomethane to a polymer solution obtained by dissolving the solid polymer in an organic solvent to form a quaternary piperidinium salt; (V) precipitating, washing and drying the polymer solution; A method for producing a branched poly(arylpiperidinium) copolymer ionomer, comprising the steps of.

3. In Claim 2, the organic solvent in the said step (I) is a halogen-based solvent, and is one or more selected from the group consisting of dichloromethane, chloroform, dichloroethane, dibromomethane and tetrachloroethane, a method for producing a branched poly(arylpiperidinium) copolymer ionomer.

4. In Claim 2, the strong acid catalyst in the said step (II) is trifluoroacetic acid, trifluoromethanesulfonic acid, pentafluoroethanesulfonic acid, heptafluoro-1-propanesulfonic acid, perfluoropropionic acid, heptafluorobutyric acid, or a mixture thereof, a method for producing a branched poly(arylpiperidinium) copolymer ionomer.

5. In Claim 2, the organic solvent in the said step (IV) is N-methylpyrrolidone, dimethylacetamide, dimethyl sulfoxide, or dimethylformamide, a method for producing a branched poly(arylpiperidinium) copolymer ionomer.

6. An anion exchange membrane comprising the branched poly(arylpiperidinium) copolymer ionomer according to Claim 1.

7. (i) dissolving the branched poly(arylpiperidinium) copolymer ionomer according to Claim 1 in an organic solvent to form a polymer solution; (ii)A step of casting and drying the polymer solution on a glass plate to obtain a film, (iii) After treating the obtained film with 1 M NaHCO ３ or 1 M NaOH, washing several times with ultrapure water and drying. A method for producing an anion exchange membrane, comprising the above steps.

8. In claim 7, The method for producing an anion exchange membrane, wherein the concentration of the polymer solution is 2 to 30% by weight.

9. In claim 7, The drying in the step (ii) includes gradually removing the organic solvent in an oven at 80 to 90 °C for 24 hours, and then completely removing the organic solvent by heating in a vacuum oven at 120 to 150 °C for 12 hours. A method for producing an anion exchange membrane.

10. A binder for an alkaline fuel cell, comprising the branched poly(arylpiperidinium) copolymer ionomer according to claim 1.

11. An alkaline fuel cell, comprising the anion exchange membrane according to claim 6.

12. A water electrolysis device, comprising the anion exchange membrane according to claim 6.

13. A carbon dioxide reduction device, comprising the anion exchange membrane according to claim 6.

14. A vanadium redox flow battery, comprising the anion exchange membrane according to claim 6.

15. A metal-air battery, comprising the anion exchange membrane according to claim 6.

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