Anion exchange membrane containing dipole inductor as well as preparation method and application of anion exchange membrane

Abstract

The invention discloses an anion exchange membrane containing a dipole inductor and a preparation method and application of the anion exchange membrane, and belongs to the technical field of polymeric membranes, and the anion exchange membrane contains a rigid twisted dipole induced aryl monomer Ar1 and a rigid twisted aryl monomer Ar2. The anion-exchange membrane provided by the invention has good ultrahigh ionic conductivity and good dimensional stability, and can promote efficient and stable operation of water electrolysis because the microporous structure of the anion-exchange membrane can effectively promote transmission of ions; the contained full-rigid polymer main chain can limit swelling of the anion exchange membrane, and the anion exchange membrane can be applied to alkaline electrolyzed water.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of high molecular film, in particular to an anion exchange membrane containing a dipole inducer and a preparation method and application thereof. BACKGROUND

[0002] Hydrogen energy, as an ideal zero-carbon carrier with high energy density, is an ideal choice for promoting the large-scale utilization of intermittent energy sources such as solar and wind energy. Anion exchange membrane water electrolysis has the advantages of non-noble metal catalyst and low-cost membrane material, and can produce high-purity green hydrogen and adapt to fluctuating energy sources. It is a green hydrogen production technology with broad application prospects. The ionic conductivity of the anion exchange membrane directly determines the energy efficiency of the system. Especially under high current density operating conditions, slow ion transport will force the operating voltage to rise to maintain the current density, further reducing system energy efficiency. Therefore, developing advanced anion exchange membranes with high ionic conductivity and long-term operation stability is the key to the industrial application of anion exchange membrane water electrolysis technology.

[0003] In order to construct an anion exchange membrane with high ionic conductivity, it is usually necessary to construct a nanoscale microphase separation structure, and to design an anion exchange membrane with a rigid polymer main chain and inherent micropores. Traditional anion exchange membranes with microphase separation structures are usually composed of hydrophobic flexible hydrocarbon main chains or rotatable semi-rigid aryl main chains and hydrophilic cationic groups. However, such anion exchange membranes with flexible or semi-rigid main chains will face the problem of uneven distribution of hydrophilic regions, especially under the hydration of high hydrophilic groups, which will cause the main chain to move and swell. It is difficult to achieve a balance between conductivity and dimensional stability. Compared with flexible polymer chains in phase separation membranes, this anion exchange membrane with a rigid twisted structure main chain can effectively improve the problem of excessive swelling of the anion exchange membrane. The rigid twisted three-dimensional structure weakens the close packing of the polymer main chain, and promotes the formation of micropores with limited effects in the membrane, promoting the ionic conductivity of the anion exchange membrane. However, most of the microporous anion exchange membranes are introduced by a small amount of rigid twisted monomers to maintain mechanical properties. Or it is a fully rigid gel insoluble membrane, which is difficult to process.

[0004] Therefore, it has become the focus of anion exchange membrane research to construct a membrane structure that has both microphase separation and high conductivity, and can inhibit swelling through a rigid main chain to provide a limited effect. SUMMARY

[0005] The purpose of the present application is to provide an anion exchange membrane containing a dipole inducer and a preparation method and application thereof to solve the problems raised in the background art.

[0006] To achieve the above purpose, the present application provides the following technical solutions: An anion exchange membrane containing a dipole inducer has a repeating unit shown in the following structural formula: ; wherein Ar1 is a rigid twisted dipole inducer aryl monomer; Ar2 is a rigid twisted aryl monomer; the molar ratio of Ar1 to Ar2 is n:(1-n), 0

[0007] Further, the Ar1 is selected from any one of the following structures: Formula 101, Formula 102, Formula 103, Formula 104, Formula 105, Formula 106, Formula 107.

[0008] Further, the Ar2 is selected from any one of the following structures: Formula 201, Formula 202, Formula 203, Formula 204, Formula 205.

[0009] Further, the R is independently selected from any one of the following structures: Formula 301, Formula 302, Formula 303, Formula 304.

[0010] Further, the n satisfies: 0.1≤n≤0.5.

[0011] Another object of the present application is to provide a preparation method of the above-mentioned anion exchange membrane containing a dipole inducer, comprising the following steps: dissolving the rigid twisted dipole inducer aryl monomer Ar1, the rigid twisted aryl monomer Ar2 and the diketohydindole in a first organic solvent, then adding trifluoromethanesulfonic acid dropwise to react, pouring the reaction product into a poor solvent to precipitate, and separating the polymer main chain; stirring and crushing the polymer main chain, collecting the crushed pieces through filtration, washing with a potassium carbonate solution, then washing with deionized water, finally washing with anhydrous ethanol, and drying to obtain a copolymer; dissolving the copolymer in a second organic solvent, adding potassium carbonate and an ionization reagent to react, pouring the reaction product into a poor solvent to precipitate, and obtaining a long side chain quaternary ammonium salt-containing copolymer; dissolving the long side chain quaternary ammonium salt-containing copolymer in a third organic solvent, and filtering, coating the filtrate on a substrate to heat and form a film, and obtaining a semi-finished product film; The semi-finished film is peeled off from the substrate, soaked in an alkaline solution, and then washed to obtain an anion exchange film containing a dipole inducer.

[0012] Further, the molar ratio of the rigid twisted dipole inducer aryl monomer Ar1, the rigid twisted aryl monomer Ar2 and the diketohydindole is (1-5):(5-9):(10-13); the molar concentration of the diketohydindole in the first organic solvent is 1-2 mol / L; and the molar ratio of the diketohydindole to trifluoromethanesulfonic acid is 1:(4-8).

[0013] Further, the first organic solvent is dichloromethane; the second organic solvent is N-methylpyrrolidone and / or dimethyl sulfoxide; the third organic solvent is N-methylpyrrolidone and / or dimethyl sulfoxide; the poor solvent is one or more of water, methanol and ethanol; and the alkaline solution is a potassium hydroxide solution or a sodium hydroxide solution.

[0014] Further, the concentration of the potassium carbonate solution is 1-3 mol / L; the molar concentration of the copolymer in the second organic solvent is 0.01-0.05 mol / L; the molar ratio of the copolymer to the ionization reagent is 1:(1.5-2); and the molar ratio of the copolymer to potassium carbonate is 1:(2-5).

[0015] Another object of the present application is to provide an application of the above-mentioned anion exchange film containing a dipole inducer in alkaline electrolytic water.

[0016] The anion exchange film containing a dipole inducer provided by the present application is a kind of polymer material with a microporous structure and a non-aromatic ether skeleton, which has strong dimensional stability, high ionic conductivity and good mechanical strength. The anion exchange film provided by the present application overcomes the problem of poor chemical stability caused by the ether bond in the polymer main chain, and weakens the problem of large swelling of the anion exchange film through the full-rigid polymer main chain. In addition, the present application introduces a rigid twisted dipole inducer to improve the microphase separation structure of the polymer, and at the same time, the full-rigid structure of the main chain promotes the formation of micropores in the film through side chain filling to improve the ionic conductivity of the anion exchange film. The anion exchange film has high ionic conductivity and can also promote the electrochemical performance of water electrolysis. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 The synthesis route of the anion exchange film QPFXI-10 provided by the embodiment of the present application is shown in the figure.

[0018] Figure 2NMR spectra of the polymer main chain (a) and anion exchange membrane (b) QPFXI-10, QPFSI-20 and QPXTI-40 provided by the embodiments of the present application.

[0019] Figure 3 Thermogravimetric characterization of the anion exchange membranes QPFXI-10 (a), QPFSI-20 (b) and QPXTI-40 (c) provided by the embodiments of the present application.

[0020] Figure 4 Water absorption of the anion exchange membranes QPFXI-10, QPFSI-20 and QPXTI-40 provided by the embodiments of the present application at different temperatures.

[0021] Figure 5 Dimensional change rate (swelling rate) of the anion exchange membranes QPFXI-10, QPFSI-20 and QPXTI-40 provided by the embodiments of the present application at different temperatures.

[0022] Figure 6 Conductivity of various ions of the anion exchange membranes QPFXI-10, QPFSI-20 and QPXTI-40 provided by the embodiments of the present application at different temperatures.

[0023] Figure 7 Anion exchange membrane electrolysis water performance (voltage at different current densities) of the anion exchange membranes QPFXI-10, QPFSI-20 and QPXTI-40 provided by the embodiments of the present application. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present application.

[0025] In view of the problems in the prior art, the embodiments of the present application provide an anion exchange membrane containing a dipole inducer, which provides a train of thought for developing ion exchange membranes with low cost and high performance. In the embodiments of the present application, different rigid twisted structure aryl monomers, dipole inducer aryl monomers and indole monomers are used as base materials, and a copolymer containing different proportions of rigid twisted dipole inducer aryl monomers is synthesized through a fast and simple reaction. The membrane after soaking in an alkaline solution is an anion exchange membrane, which can be applied to the field of alkaline water electrolysis.

[0026] Specifically, in one embodiment of the present application, an anion exchange membrane containing a dipole inducer is provided, which has a repeating unit as shown in the following structural formula: ; wherein Ar1 is a rigid twisted dipole-induced aryl monomer; Ar2 is a rigid twisted aryl monomer; the molar ratio of Ar1 to Ar2 is n:(1-n), 0

[0027] Preferably, Ar1 is selected from any one of the following structures: Formula 101, Formula 102, Formula 103, Formula 104, Formula 105, Formula 106, Formula 107.

[0028] Preferably, Ar2 is selected from any one of the following structures: Formula 201, Formula 202, Formula 203, Formula 204, Formula 205.

[0029] Preferably, R is independently selected from any one of the following structures: Formula 301, Formula 302, Formula 303, Formula 304.

[0030] Preferably, n satisfies: 0.1≤n≤0.5.

[0031] In another embodiment of the present application, a preparation method of the above-mentioned anion exchange membrane containing dipole-induced bodies is also provided, comprising the following steps: S1, dissolving the rigid twisted dipole-induced aryl monomer Ar1, the rigid twisted aryl monomer Ar2 and the diketohydindole in a first organic solvent, controlling the proportion of the dipole-induced bodies in the polymer by controlling the addition amount of the rigid twisted dipole-induced aryl monomer and the rigid twisted aryl monomer, and then slowly adding trifluoromethanesulfonic acid under ice bath for 2-10 h, precipitating the reaction product in a poor solvent to separate out the polymer main chain; S2, crushing the polymer main chain, collecting the crushed pieces by filtration, washing with potassium carbonate solution, then washing with deionized water, and finally washing with anhydrous ethanol, and drying to obtain the copolymer; wherein the washing temperature is 30-60°C; S3, dissolving the above-mentioned copolymer in a second organic solvent, adding potassium carbonate and an ionization reagent for reaction for 5-10 h, and the reaction temperature is 50-100°C, precipitating the reaction product in a poor solvent and washing to neutral, and then vacuum drying to obtain the copolymer containing long side chain quaternary ammonium salt. S4. Dissolve the above-mentioned long-side-chain quaternary ammonium salt copolymer in a third organic solvent. The concentration of the long-side-chain quaternary ammonium salt copolymer is 0.02-0.04 g / mL. Filter the solution through a 0.25-0.45 μm polytetrafluoroethylene filter. Coat the filtrate onto a substrate and heat it to 50-100°C for 5-24 h to form a film, thereby obtaining a semi-finished membrane. S5. Peel the above semi-finished membrane from the substrate and soak it in an alkaline solution for 1-24 hours at a soaking temperature of 60-80℃. Then wash it to obtain an anion exchange membrane containing a dipole inducer. It should be noted that in order to avoid CO2 pollution and carbonate formation, the anion exchange membrane can be stored in deionized water with nitrogen gas.

[0032] Preferably, the molar ratio of rigidly twisted dipole-induced aryl monomer Ar1, rigidly twisted aryl monomer Ar2, and diketadihydroindole is (1-5):(5-9):(10-13); the molar concentration of diketadihydroindole in the first organic solvent is 1-2 mol / L; the molar ratio of diketadihydroindole to trifluoromethanesulfonic acid is 1:(4-8); the first organic solvent is dichloromethane; the second organic solvent is N-methylpyrrolidone and / or dimethyl sulfoxide; the third organic solvent is N-methylpyrrolidone and / or dimethyl sulfoxide; the inferior solvent is one or more of water, methanol, and ethanol; the alkaline solution is potassium hydroxide solution or sodium hydroxide solution with a concentration of 1-2 mol / L; the concentration of potassium carbonate solution is 1-3 mol / L; the molar concentration of the copolymer in the second organic solvent is 0.01-0.05 mmol / L; the molar ratio of the copolymer to the ionizing reagent is 1:(1.5-2); and the molar ratio of the copolymer to potassium carbonate is 1:(2-5).

[0033] In this embodiment of the invention, a rigid polymer backbone containing a dipole inducer is provided, and micropores are formed by side chain filling to obtain an anion exchange membrane. This polymer backbone is prepared by Friedel-Crafts hydroxyalkylation of a rigid, twisted benzene derivative containing an electron-donating group with an indole ketone. By controlling the monomer feeding ratio to adjust the content of rigid units of different types of dipole inducers in the polymer chain segments, a polymer backbone containing dipole inducers and possessing micropores, and an anion exchange membrane can be synthesized. The anion exchange membrane prepared in this embodiment of the invention exhibits excellent ultra-high ionic conductivity and good dimensional stability, which can promote efficient and stable water electrolysis. This is because the microporous structure of the anion exchange membrane effectively promotes ion transport, and the rigid polymer backbone limits the swelling of the anion exchange membrane, making it applicable to alkaline water electrolysis.

[0034] Example 1: As Figure 1 As shown, this embodiment provides a method for preparing anion exchange membrane containing a dipole inducer, comprising the following steps: S1, Preparation of polymer backbone with Ar1 (structure formula is formula 101) and Ar2 (structure formula is formula 201) in a molar ratio of 1:9: 9, 9-dimethylfluorene (1.75 g, 9 mmol), 9, 9-dimethylxanthene (0.21 g, 1 mmol) and diketohydroindole (2.73 g, 13 mmol) and dichloromethane (20 mL) are poured into a 50 mL round-bottom flask equipped with a magnetic stirrer. Slowly add trifluoromethanesulfonic acid (4.6 mL, 52 mmol) under ice bath, react at 25°C for 6 hours, the solution color changes from orange to dark red, a viscous liquid is obtained. Pour the viscous liquid into excess ethanol to precipitate a light yellow polymer backbone, the structure formula is as follows: .

[0035] S2, Stir the above polymer backbone, collect the fragments by filtration, wash with 2 mol / L potassium carbonate solution for 3 times, then wash with deionized water for 3 times, and finally wash with anhydrous ethanol for 3 times, dry to obtain copolymer PFXI-10; the temperature of the washing process is controlled at 45°C.

[0036] S3, Copolymer grafting long side chain quaternary ammonium salt: under nitrogen environment, the above copolymer PFXI-10 (3 g, 4.3 mmol) is dissolved in 75 mL dimethyl sulfoxide, potassium carbonate (0.83 g, 6 mmol) and ionization reagent 3-(6-bromohexyl)-1-methyl quaternary ammonium salt (1.43 g, 6 mmol) are added for reaction, heated to 100°C and stirred for 12 hours. Pour the reaction mixture into deionized water to precipitate, and wash to neutral, put the product into a vacuum drying oven to dry, to long side chain quaternary ammonium salt copolymer QPFXI-10.

[0037] S4, weigh 0.22 g of the above prepared long side chain quaternary ammonium salt containing copolymer in 8 mL dimethyl sulfoxide to obtain a polymer solution; filter the polymer solution through a 0.3 μm polytetrafluoroethylene filter, and cast the filtrate on a glass plate and heat to 70°C for film forming for 12 h to obtain Br - type quaternary ammonium salt functionalized anion exchange membrane.

[0038] S5, peel the above Br - type quaternary ammonium salt functionalized anion exchange membrane from the glass plate, and immerse it in 1 mol / L potassium hydroxide solution for 12 h, the soaking temperature is 60°C, then wash with deionized water to obtain OH - type anion exchange membrane containing dipole inducer QPFXI-10, the structure formula (R corresponds to formula 301) is as follows: .

[0039] Embodiment 2: The embodiment provides a preparation method of an anion exchange membrane containing a dipole inducer, comprising the following steps: S1, preparing a polymer main chain with a molar ratio of Ar1 (the structural formula is formula 102) to Ar2 (the structural formula is formula 205) of 2:8: a 50 mL round-bottom flask is filled with fluorene (1.33 g, 8 mmol), 9,9-dimethylthioxanthene (0.45 g, 2 mmol), diketohydindole (2.73 g, 13 mmol) and dichloromethane (20 mL) and a magnetic stirrer is installed. Under an ice bath, trifluoromethanesulfonic acid (6 mL, 67 mmol) is slowly added dropwise, and the solution is reacted at 25°C for 6 hours, and the color of the solution changes from orange to dark red to obtain a viscous liquid. The viscous liquid is poured into an excess of ethanol to precipitate a light yellow polymer main chain, and the structural formula is as follows: .

[0040] S2, the polymer main chain is stirred and crushed, the crushed pieces are collected by filtration, washed with 2 mol / L potassium carbonate solution for 3 times, then washed with deionized water for 3 times, and finally washed with anhydrous ethanol for 3 times, and dried to obtain the copolymer PFSI-20; wherein the temperature of the washing process is controlled at 45°C.

[0041] S3, the copolymer is grafted with long side chain quaternary ammonium salt: under a nitrogen environment, the copolymer PFSI-20 (3 g, 0.93 mmol) is dissolved in 75 mL of dimethyl sulfoxide, potassium carbonate (0.83 g, 6 mmol) and ionization reagent 3-(6-bromohexyl)-1-methyl quaternary ammonium salt (1.43 g, 6 mmol) are added for reaction, and heated to 100°C for 12 hours of continuous stirring. The reaction mixture is poured into deionized water for precipitation, and washed to neutral, and the product is placed in a vacuum drying oven for drying, to obtain the long side chain quaternary ammonium salt copolymer QPFSI-20.

[0042] S4, 0.22 g of the long side chain quaternary ammonium salt copolymer prepared above is weighed and dissolved in 8 mL of dimethyl sulfoxide to obtain a polymer solution; the polymer solution is filtered through a 0.3 μm polytetrafluoroethylene filter, and the filtrate is cast on a glass plate and heated to 70°C for film formation for 12 hours to obtain a Br - type quaternary ammonium salt functionalized anion exchange membrane.

[0043] S5, the Br - type quaternary ammonium salt functionalized anion exchange membrane is peeled off from the glass plate and soaked in a 1 mol / L potassium hydroxide solution for 12 hours, the soaking temperature is 60°C, and then washed with deionized water to obtain an OH - type anion exchange membrane containing a dipole inducer QPFSI-20, and the structural formula (R corresponds to formula 301) is as follows: .

[0044] Example 3: The embodiment provides a preparation method of an anion exchange membrane containing a dipole inducer, comprising the following steps: S1, preparing a polymer main chain with a molar ratio of Ar1 (structural formula is formula 101) to Ar2 (structural formula is formula 203) of 4:6: meta-triphenyl (1.38 g, 6 mmol), 9,9-dimethylxanthene (0.84 g, 4 mmol), and diketohydroindole (2.73 g, 13 mmol) and dichloromethane (20 mL) are poured into a 50 mL round-bottom flask equipped with a magnetic stirrer. Slowly add trifluoromethanesulfonic acid (8 mL, 90 mmol) under ice bath, react at 25°C for 6 hours, and the solution color changes from orange to dark red to obtain a viscous liquid. Pour the viscous liquid into excess ethanol to precipitate a light yellow polymer main chain, and the structural formula is as follows: .

[0045] S2, stir the polymer main chain, collect the fragments, wash with 2 mol / L potassium carbonate solution for 3 times, then wash with deionized water for 3 times, and finally wash with anhydrous ethanol for 3 times, and dry to obtain the copolymer PFXI-40; wherein the temperature of the washing process is controlled at 45°C.

[0046] S3, grafting long side chain quaternary ammonium salt to the copolymer: under nitrogen environment, dissolve the copolymer PFXI-40 (3 g, 4.1 mmol) in 75 mL dimethyl sulfoxide, add potassium carbonate (0.83 g, 6 mmol) and ionization reagent 3-(6-bromohexyl)-1-methyl quaternary ammonium salt (1.43 g, 6 mmol) to react, heat to 100°C and continue to stir for 12 hours. Pour the reaction mixture into deionized water to precipitate, and wash to neutral, and dry the product in a vacuum drying oven to obtain the long side chain quaternary ammonium salt copolymer QPFXI-40.

[0047] S4, weigh 0.22 g of the prepared long side chain quaternary ammonium salt copolymer and dissolve it in 8 mL of dimethyl sulfoxide to obtain a polymer solution; filter the polymer solution through a 0.3 μm polytetrafluoroethylene filter, and cast the filtrate on a glass plate and heat to 70°C for film formation for 12 h to obtain a Br - type quaternary ammonium salt functionalized anion exchange membrane.

[0048] S5, peel the Br - type quaternary ammonium salt functionalized anion exchange membrane from the glass plate, and immerse it in a 1 mol / L potassium hydroxide solution for 12 h, the immersion temperature is 60°C, then wash with deionized water to obtain an OH - type anion exchange membrane containing a dipole inducer QPFXI-40, and the structural formula (R corresponds to formula 301) is as follows: .

[0049] Performance test: The polymer main chain and OH - type anion exchange membranes containing dipole inducer (QPFXI-10, QPFSI-20 and QPXTI-40) were structurally characterized by nuclear magnetic spectroscopy, as shown in Figure 2 , to confirm the synthesis of the target compound.

[0050] The OH - type anion exchange membranes containing dipole inducer (QPFXI-10, QPFSI-20 and QPXTI-40) were taken as samples, and the dry samples were heated from 80℃ to 800℃ at a heating rate of 10℃ / min in a nitrogen atmosphere, to obtain the degradation change curve of the polymer with the increase of temperature, as shown in Figure 3 It can be concluded that the polymer does not decompose within 200℃, and is suitable for anion exchange membrane electrolysis water application. Figure 3

[0051] The OH - type anion exchange membranes containing dipole inducer (QPFXI-10, QPFSI-20 and QPXTI-40) were taken as samples, and the water absorption (WU) and swelling ratio (SR) tests were carried out, and the test results are shown in Figure 4 and Figure 5 , and the test method is as follows: after the dry film sample is immersed in deionized water at different temperatures for 24h, the film sample is fully water-absorbed to saturation, the mass of the film sample before and after soaking is measured, and is recorded as W dry , W wet ; the length of the film sample before and after soaking is measured, and is recorded as L dry , L wet ; the calculation method of water absorption (WU) and swelling ratio (SR) is as follows: ; ; The OH - type anion exchange membranes containing dipole inducer (QPFXI-10, QPFSI-20 and QPXTI-40) were taken as samples, and the conductivity test was carried out, and the results are shown in Figure 6 ​The conductivity of the membrane sample at 30-80 DEG C was tested by using an alternating current impedance method (EIS), and the test was measured by using a CHI760e electrochemical workstation, the test frequency was 1 MHz-0.01 Hz, in the experiment, the membrane sample was cut into a size of 10 mm*50 mm, the membrane sample was placed in a polytetrafluoroethylene clamp, and the test was carried out under the condition of 100% humidity, and finally the ionic conductivity of the sample was calculated according to the formula; sigma = L / (wdR); in the formula, L is the length of the membrane between the electrodes (cm), w is the width of the membrane (cm), d is the thickness of the membrane (cm), and R is the measured resistance of the membrane (Omega).

[0052] OH - The anion exchange membrane electrolysis water performance test was carried out on the anion exchange membranes (QPFXI-10, QPFSI-20 and QPXTI-40) containing dipole inducers prepared in examples 1-3, and the test results are shown in table 7; from Figure 7 It can be seen that the current density of 1.5 A·cm -2 Can be reached at 2V, 80 DEG C. The test method is as follows: during the test, the assembled battery is kept at 80 DEG C, the cathode provides 10 mL / min of CO2 gas, and during the operation, the cathode gas is introduced into the cathode under the condition that the relative humidity is 100% and the temperature is 60 DEG C. The anode is introduced into 1 mol / L KOH solution heated to 80 DEG C at a flow rate of 10 mL / min.

[0053] In summary, the anion exchange membrane containing a dipole inducer provided by the embodiments of the present application has the following beneficial effects compared with the prior art: (1) The preparation process of the anion exchange membrane provided by the embodiments of the present application is simple, the reaction activity can be improved by using rigid twisted benzene-based monomers and high-activity reaction monomers of indole, the catalyst usage can be reduced, and the cost can be reduced; (2) The embodiments of the present application introduce a rigid twisted dipole induction unit to synthesize a polymer containing a long side chain quaternary ammonium salt, which promotes the formation of micropores and ion clusters in the membrane and the hydrophilic and hydrophobic microphase separation, and can significantly improve the conductivity of the anion exchange membrane; (3) The embodiments of the present application introduce a rigid twisted main chain structure, which can effectively inhibit the excessive swelling of the anion exchange membrane; (4) The embodiments of the present application use an ether-free polymer main chain, which can reduce the risk of hydroxyl attacking the anion exchange membrane, thereby enhancing the alkali resistance of the anion exchange membrane.

[0054] Based on the above ideal embodiments according to the present application, through the above description, relevant personnel can make various changes and modifications without deviating from the technical idea of the present application. The technical scope of the present application is not limited to the contents in the specification.

Claims

1. An anion exchange membrane containing a dipole inducer, characterized in that, It has repeating units as shown in the following structural formula: ； Wherein, Ar1 is a rigid twisted dipole-induced aryl monomer; Ar2 is a rigid twisted aryl monomer; the molar ratio of Ar1 to Ar2 is n:(1-n), 0<n<1; R is a nitrogen-containing group.

2. The anion exchange membrane containing a dipole inducer according to claim 1, characterized in that, The Ar1 is selected from any of the following structures: Formula 101 Formula 102 Formula 103 Formula 104 Formula 105 Formula 106 Formula 107.

3. The anion exchange membrane containing a dipole inducer according to claim 1, characterized in that, The Ar2 is selected from any of the following structures: Formula 201 Formula 202 Formula 203 Equation 204 Formula 205.

4. The anion exchange membrane containing a dipole inducer according to claim 1, characterized in that, The R is independently selected from any of the following structures: Formula 301 Formula 302 Formula 303 Formula 304.

5. The anion exchange membrane containing a dipole inducer according to claim 1, characterized in that, The n satisfies: 0.1≤n≤0.

5.

6. A method for preparing an anion exchange membrane containing a dipole inducer as described in any one of claims 1-5, characterized in that, Includes the following steps: Rigid twisted dipole-induced aryl monomer Ar1, rigid twisted aryl monomer Ar2 and diketone dihydroindole are dissolved in a first organic solvent, and then trifluoromethanesulfonic acid is added dropwise to carry out the reaction. The reaction product is poured into a inferior solvent to precipitate and the polymer backbone is precipitated. The polymer backbone was broken up, the fragments were collected by filtration, washed with potassium carbonate solution, then washed with deionized water, and finally washed with anhydrous ethanol. After drying, the copolymer was obtained. The copolymer was dissolved in a second organic solvent, potassium carbonate and an ionizing agent were added to react, and the reactants were poured into a poor solvent to precipitate, thus obtaining a copolymer containing long side-chain quaternary ammonium salts. The copolymer containing long side chain quaternary ammonium salt is dissolved in a third organic solvent and filtered. The filtrate is coated on a substrate and heated to form a film, thus obtaining a semi-finished film. The semi-finished membrane is peeled off from the substrate and soaked in an alkaline solution, and then washed to obtain an anion exchange membrane containing a dipole inducer.

7. The method for preparing anion exchange membrane containing a dipole inducer according to claim 6, characterized in that, The molar ratio of the rigid twisted dipole-induced aryl monomer Ar1, the rigid twisted aryl monomer Ar2, and the diketone dihydroindole is (1-5):(5-9):(10-13); the molar concentration of the diketone dihydroindole in the first organic solvent is 1-2 mol / L; and the molar ratio of the diketone dihydroindole to trifluoromethanesulfonic acid is 1:(4-8).

8. The method for preparing anion exchange membrane containing a dipole inducer according to claim 6, characterized in that, The first organic solvent is dichloromethane; the second organic solvent is N-methylpyrrolidone and / or dimethyl sulfoxide; the third organic solvent is N-methylpyrrolidone and / or dimethyl sulfoxide; the inferior solvent is one or more of water, methanol, and ethanol; and the alkaline solution is potassium hydroxide solution or sodium hydroxide solution.

9. The method for preparing anion exchange membrane containing a dipole inducer according to claim 6, characterized in that, The concentration of the potassium carbonate solution is 1-3 mol / L; the molar concentration of the copolymer in the second organic solvent is 0.01-0.05 mol / L; the molar ratio of the copolymer to the ionizing reagent is 1:(1.5-2); and the molar ratio of the copolymer to potassium carbonate is 1:(2-5).

10. The application of an anion exchange membrane containing a dipole inducer as described in any one of claims 1-5 in alkaline water electrolysis.

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