Azulenyl-branched poly(aryl-piperidine) anion exchange membrane, and preparation method therefor and use thereof

Abstract

The present invention relates to the technical field of membranes, and discloses an azulenyl-branched poly(aryl-piperidine) anion exchange membrane, and a preparation method therefor and the use thereof. The specific preparation method comprises: preparing an azulenyl-branched poly(aryl-piperidine) precursor; preparing cationized azulenyl-branched poly(aryl-piperidine); and preparing an azulenyl-branched poly(aryl-piperidine) anion exchange membrane. In this way, an alkaline anion exchange membrane is prepared by means of polymerization and quaternization, wherein a branched structure generates high mechanical strength and greatly reduces the water absorption and swelling rate of the anion exchange membrane, thereby improving the dimensional stability; moreover, a highly stable cationic group and a nucleophilic azulenyl group increase the alkaline stability thereof. The high OH- electrical conductivity, alkaline stability and high mechanical strength thereof indicate that the azulenyl-branched poly(aryl-piperidine) anion exchange membrane prepared by the method can be used as an anion exchange membrane material for alkaline fuel cells and alkaline electrolytic cells.

Description

An azulenyl branched poly(aryl-piperidine) anion exchange membrane, its preparation method and application TECHNICAL FIELD

[0001] The present application relates to the technical field of membranes, in particular to an azulenyl branched poly(aryl-piperidine) anion exchange membrane, its preparation method and application. BACKGROUND

[0002] Due to global development and population growth, the energy demand in the world continues to grow rapidly. Developing clean and efficient hydrogen energy is in line with the energy strategy of "carbon peak" and "carbon neutralization", which helps to achieve sustainable development of mankind. Green hydrogen can be produced by water electrolysis technology driven by "abandoned light-abandoned wind-waste electricity" with excess capacity, and fuel cells are the main application direction of hydrogen energy. At present, proton exchange membrane fuel cells and acid electrolysis cells operating in acidic conditions require the use of noble metal catalysts and expensive proton exchange membranes, and the cost of producing and utilizing hydrogen is too high, which has greatly hindered the industrialization development. Anion exchange membrane fuel cells and alkaline water electrolysis technology can use low-alkaline electrolyte and non-noble metal catalyst, greatly reducing the operating cost, and therefore have attracted widespread attention.

[0003] Anion exchange membrane (AEM) is a key component of anion exchange membrane fuel cells and alkaline electrolysis cells, and it is crucial to prepare anion exchange membranes with high hydroxyl ion conductivity and stable chemical properties, so as to realize high power density and long-term durability of anion exchange membrane fuel cells and alkaline electrolysis cells. AEM is composed of a polymer backbone, a cationic group and a mobile ion. The structure of the polymer backbone and the properties of the cationic group directly determine the performance of the AEM. The research of AEM still faces the following technical bottlenecks: (1) Due to the fact that the radius of OH - is larger than that of H + , the OH - conductivity of AEM is only 20% to 33% of the H + conductivity of proton exchange membrane under the same conditions, and the most direct way to improve the conductivity is to increase the ion exchange capacity (IEC), which means that more hydrophilic cationic groups need to be introduced, which will increase the water absorption rate of the membrane and cause the swelling to be larger, thereby causing the mechanical properties of the membrane to decrease. Therefore, it is crucial to solve the "trade-off" effect between the ion conductivity and the dimensional stability of the membrane for the development of AEM. (2) Under the condition of hot alkali, the polymer backbone and the cationic group are easily attacked by the nucleophilic OH - , which causes complex degradation reactions of the main chain structure and the cationic group, thereby causing the performance of the membrane to decrease and even reducing the service life of the AEM.

[0004] Therefore, it is an urgent problem to be solved to improve the alkaline stability of AEM and prolong the service life of the membrane.

[0005] SUMMARY

[0006] In order to solve the above technical problems existing in the prior art, the present application provides an azulene branched poly(aryl-piperidine) anion exchange membrane, a preparation method and application thereof, so as to overcome the problems of low ion conductivity and poor alkaline stability of AEM in the prior art.

[0007] In order to achieve the above-mentioned purpose, the technical scheme of the embodiments of the present application is:

[0008] The first aspect of the present application provides an azulene branched poly(aryl-piperidine) anion exchange membrane, which contains an azulene branched poly(aryl-piperidine) polymer and has the following structure:

[0009] wherein R is an aromatic group, A is an azulene branched group, a is any integer greater than or equal to 0, and b is any integer greater than or equal to 1.

[0010] In combination with the first aspect, preferably, the R is at least one of the following structures:

[0011] wherein R1 and R2 are at least one of H atoms, aliphatic or aromatic long chains.

[0012] In combination with the first aspect, preferably, the A is at least one of the following structures:

[0013] The second aspect of the present application provides a preparation method of the azulene branched poly(aryl-piperidine) anion exchange membrane of the first aspect, which comprises:

[0014] (1) preparing an azulene branched poly(aryl-piperidine) precursor:

[0015] dissolving aromatic monomers, azulene branched monomers and N-methyl-4-piperidone in a first organic solvent, adding trifluoroacetic acid and trifluoromethanesulfonic acid, and then collecting the azulene branched poly(aryl-piperidine) precursor after reaction;

[0016] (2) preparing a cationic azulene branched poly(aryl-piperidine):

[0017] dissolving the azulene branched poly(aryl-piperidine) precursor in a second organic solvent, adding potassium carbonate and iodomethane, and then collecting the cationic azulene branched poly(aryl-piperidine) after dark reaction and purification treatment with ethyl acetate;

[0018] (3) Preparation of azulene-branched poly(aryl-piperidine) anion exchange membrane:

[0019] Dissolve the cationic azulene-branched poly(aryl-piperidine) in a third organic solvent and collect Cl. - Type thin film, making the Cl - Ion exchange is performed on a thin film to obtain OH-. - After purification, the azulene-branched poly(aryl-piperidine) anion exchange membrane was collected.

[0020] Preferably, in conjunction with the second aspect, the molar ratio of the aromatic monomer to the azulene branched monomer is 0-99:1;

[0021] And / or, the molar ratio of the sum of the amounts of the azulene branched monomer and the aromatic monomer to the amount of the N-methyl-4-piperidinone is 1:0.9-1.2.

[0022] Preferably, in conjunction with the second aspect, the molar ratio of N-methyl-4-piperidinone to trifluoroacetic acid is 1:0.8-1.2;

[0023] And / or, the molar ratio of the N-methyl-4-piperidinone to the trifluoromethanesulfonic acid is 1:8-12.

[0024] Preferably, in conjunction with the second aspect, the first organic solvent is one or more of chloroform, dichloromethane, carbon tetrachloride, dichloroethane, and 1,1,2,2-tetrachloroethane.

[0025] Preferably, in conjunction with the second aspect, the second organic solvent is one or more of acetonitrile, tetrahydrofuran, N-methylpyrrolidone, dimethyl sulfoxide, N,N-dimethylacetamide, N,N-dimethylformamide, and sulfolane.

[0026] The third aspect of this application provides an azulene-branched poly(aryl-piperidine) anion exchange membrane as described in the first aspect, and the azulene-branched poly(aryl-piperidine) anion exchange membrane prepared by the method described in the second aspect for use in the preparation of alkaline fuel cells and alkaline electrolyzers.

[0027] Compared with the prior art, the advantages or beneficial effects of the embodiments of this application include at least the following:

[0028] The azulene-branched poly(aryl-piperidine) anion exchange membrane provided in this application is a basic anion exchange membrane prepared by polymerization and quaternization. The branched structure generates high mechanical strength, significantly reducing the water absorption and swelling rate of the anion exchange membrane, thereby improving dimensional stability. Simultaneously, the highly stable cationic groups and nucleophilic azulene groups increase its basic stability, and its high OH... -The conductivity, alkaline stability and high mechanical strength show that the azulene branched poly(aryl-piperidine) anion exchange membrane prepared in the application can be used as an anion exchange membrane material for alkaline fuel cells and alkaline electrolytic cells.

[0029] The azulene branched poly(aryl-piperidine) anion exchange membrane provided by the application has high OH - The conductivity (at 80℃, OH - The conductivity is >100 mS cm -1 , high mechanical strength (tensile strength >35 MPa, elongation at break >10%), high dimensional stability, good processing performance, and excellent alkaline stability (>500h) in 1M KOH at 80℃.

[0030] Compared with other types of branched poly(aryl-piperidine) anion exchange membranes, the introduction of the nucleophilic azulene group in the molecular structure makes the structure not easy to be attacked by OH - , and enhances the alkaline stability thereof; the formation of the branched structure makes the molecular chains intertangled with each other, and enhances the mechanical performance thereof. BRIEF DESCRIPTION OF DRAWINGS

[0031] Figure 1 is a synthesis path diagram of the 6,6'-linked azulene branched poly(p-terphenyl-piperidine) precursor polymer provided by the application;

[0032] Figure 2 is a synthesis path diagram of the 6,6'-linked azulene branched poly(p-terphenyl-piperidine) (h-PTP-BiAz-n) provided by the application;

[0033] Figure 3 is a mechanical performance comparison diagram of the azulene branched poly(p-terphenyl-piperidine) anion exchange membranes prepared in Examples 1 and 2 and the poly(p-terphenyl-piperidine) anion exchange membrane prepared in Comparative Example 1;

[0034] Figure 4 is a swelling rate test result of the azulene branched poly(p-terphenyl-piperidine) anion exchange membranes prepared in Examples 1 and 2;

[0035] Figure 5 is an anion exchange membrane electrolysis water test result of the azulene branched poly(p-terphenyl-piperidine) anion exchange membranes prepared in Examples 1 and 2. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical scheme and advantages of the application more clear, the application will be further described in detail below in combination with the drawings, and the described embodiments should not be regarded as a limitation on the application, and all other embodiments obtained by those skilled in the art without making creative efforts fall within the protection scope of the application.

[0037] In the following description, reference is made to "some embodiments", which describe a subset of all possible embodiments, but it is understood that "some embodiments" can be the same subset or different subsets as each other and can be combined with each other, without conflict. Unless otherwise defined, all technical and scientific terms used in the present embodiments have the same meaning as those commonly understood by one of ordinary skill in the art to which the present embodiments belong. The terms used in the present embodiments are only for the purpose of describing the present embodiments and are not intended to limit the present application.

[0038] In the following description of the present embodiments, the terms "comprising", "containing", "having" and "including" and the like are open-ended terms, i.e., they mean including but not limited to.

[0039] It should be noted that all raw materials / reagents in the present embodiments can be purchased on the market or prepared according to conventional methods well known to those skilled in the art; the term "and / or" in the present embodiments is only used to describe the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B means that there are three cases of A alone, B alone, and A and B together, wherein A and B can be singular or plural, and the character " / " generally represents an "or" relationship between the associated objects before and after it.

[0040] In the following description of the present embodiments, the term "at least one" means one or more, and "multiple" means two or more. "At least one of the following" or the like means any combination of the items, including any combination of single item or multiple items. For example, "at least one of a, b or c", or "at least one of a, b and c", can mean a, b, c, a-b (i.e., a and b), a-c, b-c, or a-b-c, wherein a, b, and c can be single or multiple.

[0041] Those skilled in the art should understand that in the following description of the present embodiments, the order of the serial numbers does not mean the order of execution, and some or all steps can be executed in parallel or in sequence, and the execution order of each process should be determined according to its function and inherent logic, and should not constitute any limitation on the implementation process of the present embodiments.

[0042] The terms used in the present embodiments are only for the purpose of describing the specific embodiments, and are not intended to limit the present application. The singular forms "a" and "the" used in the present embodiments and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise.

[0043] It should be understood by those skilled in the art that numerical ranges in the embodiments of the present application are to be understood to include each and every intervening value or sub-range between the upper and lower limits of that range. Intervening numerical values and sub-ranges that are within any stated range or within any stated sub-range are expressly included within the scope of the present application. Upper and lower limits of these smaller ranges and sub-ranges can independently be included or excluded in the range.

[0044] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. Although any methods and materials similar or equivalent to those described herein can be used in the practice of the present application, the preferred methods and materials are described herein. All documents mentioned herein are incorporated by reference for the disclosure and description in connection with the methods and / or materials associated with the documents. In the case of conflict, the present document will control.

[0045] It should be noted that all raw materials and / or reagents used in the embodiments of the present application are commercially available or prepared according to conventional methods well known to those skilled in the art.

[0046] The following are the test methods used in the examples:

[0047] Performance tests:

[0048] The equipment and test methods involved in the examples:

[0049] Ion exchange capacity (IEC) test method: Take the Cl - or Br - type or Br type film, vacuum oven 75℃ drying and weighing, record the dry film weight. The dry film is immersed in 25 mL of 0.2M NaNO3 solution for 6h, repeated three times, and the NaNO3 solution after ion exchange is collected. Add indicator potassium chromate solution to the solution, and titrate with 0.01M AgNO3 standard solution, when brick red precipitate appears and does not disappear after shaking, it means titration is complete. Record the volume of AgNO3 solution consumed. The concentration of AgNO3 solution is divided by the volume to obtain the IEC of the dry film.

[0050] The conductivity was measured by electrochemical workstation (CHI660E, Shanghai Chenhua Instrument Co. Ltd.) using electrochemical impedance spectroscopy (EIS). The potential amplitude was 10 mV. To reduce the error caused by the contact resistance, the resistance of the membrane was measured in the in-plane direction. The membrane was cut into 40 mm x 10 mm and placed in the clamp. The clamp was placed in pure water, and the temperature was from 30 to 80 °C. The resistance of the membrane was measured every 10 °C, and the sample was kept for 1 h before testing. Finally, the ionic conductivity of the sample was calculated according to the formula: σ = l / (wdR), where 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 (μm), and R is the measured resistance of the membrane (mΩ).

[0051] Alkaline fuel cell performance test: the instrument used was produced by the United States Scribner Associates co. company, the instrument model was 850e multi-range fuel cell test system, and the test was carried out under current mode. The test conditions were complete humidification of H2 and O2, the test temperature was 60 °C, 80 °C, and the flow rate of H2 and O2 was 200 mL / min.

[0052] Anion exchange membrane electrolysis water performance test: the anode was a titanium felt loaded with IrO2, the cathode was a carbon paper loaded with Pt / C, the electrode area was 4 cm 2 , and the electrolyte was 1M KOH. The MEA electrolysis cell was assembled. The test instrument was CHI660e, and the linear voltammetry scanning test was carried out on the electrolysis cell.

[0053] Tensile strength test: the dry membrane sample 5 x 0.5 cm was tested by Instron M3300 electronic universal testing machine, and the tensile rate was 5 mm / min.

[0054] Alkaline stability test: the prepared anion exchange membrane was immersed in NaOH solution with different concentrations at different temperatures, and the conductivity was measured at the same time. The alkaline stability of the electrolyte membrane was analyzed by the change of the conductivity of the electrolyte membrane.

[0055] In a first aspect, the embodiments of the present application provide an azulene branched poly(aryl-piperidine) anion exchange membrane, which contains an azulene branched poly(aryl-piperidine) polymer and has the following structure:

[0056] wherein R is an aromatic group, A is an azulene branched group, a is any integer greater than or equal to 0, and b is any integer greater than or equal to 1.

[0057] The azulene branched poly(aryl-piperidine) anion exchange membrane provided by the embodiment of the present application is prepared by polymerization and quaternization, and is a basic anion exchange membrane, wherein the branched structure produces high mechanical strength, greatly reduces the water absorption and swelling rate of the anion exchange membrane, thereby improving the dimensional stability; meanwhile, the high stability cationic group and nucleophilic azulene group increase the basic stability thereof, the high OH - The high conductivity, basic stability and high mechanical strength show that the azulene branched poly(aryl-piperidine) anion exchange membrane prepared by the present application can be used as an anion exchange membrane material for basic fuel cells and basic electrolytic cells.

[0058] In specific embodiments, R in the embodiment of the present application is preferably one of the following structures:

[0059] Preferably, R1 and R2 are one of H atom, aliphatic or aromatic long chain.

[0060] In specific embodiments, A in the embodiment of the present application is preferably one of the following structures:

[0061] In a second aspect, the present application provides a preparation method of the azulene branched poly(aryl-piperidine) anion exchange membrane of the first aspect, and the preparation method comprises:

[0062] (1) preparing an azulene branched poly(aryl-piperidine) precursor:

[0063] The aromatic monomer, azulene branched monomer and N-methyl-4-piperidone are dissolved in a first organic solvent, trifluoroacetic acid and trifluoromethanesulfonic acid are added, and after reaction, the azulene branched poly(aryl-piperidine) precursor is collected;

[0064] (2) preparing a cationized azulene branched poly(aryl-piperidine):

[0065] The azulene branched poly(aryl-piperidine) precursor is dissolved in a second organic solvent, potassium carbonate and iodomethane are added, and after light-avoiding reaction, ethyl acetate is added, and the cationized azulene branched poly(aryl-piperidine) is collected after purification treatment;

[0066] (3) preparing an azulene branched poly(aryl-piperidine) anion exchange membrane:

[0067] The cationized azulene branched poly(aryl-piperidine) is dissolved in a third organic solvent, and the Cl - type film is collected, the Cl - type film is subjected to ion exchange, and the OH- After purification, the azulene-branched poly(aryl-piperidine) anion exchange membrane was collected.

[0068] It should be noted that the azulene-branched poly(aryl-piperidine) precursor in the embodiments of this application is prepared by the following method: firstly, aromatic monomers, azulene-branched monomers and N-methyl-4-piperidinone are dissolved in a first organic solvent in a certain proportion to obtain a mixture. The mixture is stirred and reacted at 0-4℃ for 30 min. Then, a certain proportion of trifluoroacetic acid and trifluoromethanesulfonic acid are added. After reacting at 0-4℃ for a certain time, the resulting viscous solution is placed in excess methanol to precipitate. The obtained polymer solid is collected, washed with potassium carbonate solution and dried to obtain the azulene-branched poly(aryl-piperidine) precursor.

[0069] It should be noted that the collection of azulene branched poly(aryl-piperidine) precursor in the embodiments of this application includes: washing with potassium carbonate solution overnight, then washing three times with deionized water, and vacuum drying.

[0070] This application does not specify particular drying conditions, as long as a product of constant weight is obtained. In the embodiments of this application, the drying temperature is preferably 80°C, and the drying time is preferably 24 hours.

[0071] It should be noted that in the embodiments of this application, the reaction was carried out at room temperature with stirring in the dark for 24 hours.

[0072] It should be noted that, in the embodiments of this application, N-methyl-4-piperidinone reacts with iodomethane to form a quaternary ammonium cation.

[0073] It should be noted that ethyl acetate in the embodiments of this application is a good solvent for iodomethane, which can dissolve unreacted monomers. At the same time, it is a poor solvent for polymers, causing the polymers to precipitate and thus purifying the polymers.

[0074] In a specific embodiment, the molar ratio of the aromatic monomer to the azulene branched monomer in this application embodiment is preferably 0-99:1.

[0075] Specifically, when the molar ratio of aromatic monomer to azulene branched monomer is greater than 99:1, i.e. when the content of azulene branched monomer is too low, the azulene branched monomer has a weak effect on improving the performance of the anion exchange membrane.

[0076] In a specific embodiment, the molar ratio of the sum of the amounts of azulene branched monomers and aromatic monomers to the amount of N-methyl-4-piperidinone added is preferably 1:0.9-1.2.

[0077] In a specific embodiment, the molar ratio of N-methyl-4-piperidinone to trifluoroacetic acid is preferably 1:0.8-1.2.

[0078] When the molar ratio of N-methyl-4-piperidone to trifluoroacetic acid is less than 1:1.2, the reaction rate will decrease; when the molar ratio of N-methyl-4-piperidone to trifluoroacetic acid is greater than 1:0.8, the subsequent reaction (addition of trifluoromethanesulfonic acid) can be accompanied by severe fuming.

[0079] In specific embodiments, the molar ratio of N-methyl-4-piperidone to trifluoromethanesulfonic acid in the embodiments of the present application is preferably 1:8-12.

[0080] When the molar ratio of N-methyl-4-piperidone to trifluoromethanesulfonic acid is less than 1:12, local polymerization rate can be too fast, resulting in a too wide molecular weight distribution; when the molar ratio of N-methyl-4-piperidone to trifluoromethanesulfonic acid is greater than 1:8, the reaction yield and rate will decrease.

[0081] In specific embodiments, the first organic solvent in the embodiments of the present application is preferably one of chloroform, dichloromethane, carbon tetrachloride, dichloroethane and 1,1,2,2-tetrachloroethane.

[0082] The first organic solvents serve to dissolve the reactants.

[0083] In specific embodiments, the second organic solvent in the embodiments of the present application is preferably one of acetonitrile, tetrahydrofuran, N-methylpyrrolidone, dimethyl sulfoxide, N,N-dimethylacetamide, N,N-dimethylformamide and sulfolane.

[0084] The second organic solvents serve to dissolve the reactants and precipitate the polymer.

[0085] In a third aspect, the embodiments of the present application provide the use of the azulene-branched poly(aryl-piperidinium) anion exchange membrane of the first aspect and the azulene-branched poly(aryl-piperidinium) anion exchange membrane prepared by the method of the second aspect for preparing alkaline fuel cells and alkaline electrolytic cells.

[0086] In specific embodiments, the azulene-branched poly(p-terphenyl-piperidinium) anion exchange membrane of the embodiments of the present application has an OH - The conductivity is preferably at least 150 mS / cm.

[0087] The technical method of the present application will be further described below in conjunction with specific embodiments.

[0088] Example 1

[0089] The present embodiment 1 provides a preparation method of an azulene branched poly(p-terphenyl-piperidine) anion exchange membrane, i.e., a 6,6'-azulene branched poly(p-terphenyl-piperidine) (h-PTP-BiAz-1) anion exchange membrane, and the specific steps are as follows:

[0090] (1) Preparation of azulene branched poly(aryl-piperidine) precursor, i.e., preparation of 6,6'-azulene branched poly(p-terphenyl-piperidine) precursor polymer (h-PTP-BiAz-n):

[0091] p-terphenyl TP (2.30 g, 10 mmol), 6,6-azulene BiAz (0.025 g, 0.10 mmol), N-methyl-4-piperidone mPip (1.15 g, 10.15 mmol) are added to dichloromethane DCM (17 mL) to form a solution, the solution is stirred at 0°C for 30 min, trifluoroacetic acid TFA (0.82 mL, 10.1 mmol) and trifluoromethanesulfonic acid TFSA (8.97 mL, 101 mmol) are added dropwise into the solution, after 6 h, the obtained viscous solution is poured into excess methanol to precipitate, the obtained blue polymer fibers are collected; the solid is washed with 1M K2CO3 solution overnight at 50°C, then washed with deionized water three times, and dried at 80°C under vacuum for 24 h to obtain h-PTPE-BiAz-1. Wherein, n is the molar content in the form of percentage of BiAz monomer.

[0092] In order to facilitate the understanding of the above-mentioned synthesis process of the 6,6'-azulene branched poly(p-terphenyl-piperidine) precursor polymer, the present application provides a synthesis path diagram of the 6,6'-azulene branched poly(p-terphenyl-piperidine) precursor polymer h-PTPE-BiAz-n, as shown in Figure 1, which is a synthesis path diagram of the 6,6'-azulene branched poly(p-terphenyl-piperidine) precursor polymer provided by the present application.

[0093] (2) Preparation of cationized azulene branched poly(aryl-piperidine), i.e., 6,6'-azulene branched poly(p-terphenyl-piperidine) (h-PTP-BiAz-1):

[0094] 1g of h-PTPE-BiAz-n polymer is dissolved in 30mL of dimethyl sulfoxide (DMSO), then K2CO3 (0.39g) and iodomethane (1mL) are added, and the reaction is stirred in the dark at room temperature for 24h. Ethyl acetate is added to the obtained viscous solution. The light yellow precipitate is filtered and washed with water three times, and dried in an oven at 80°C under vacuum for 24h to obtain h-PTP-BiAz-1.

[0095] In order to facilitate the understanding of the synthesis process of the above-mentioned 6,6'-bi-azulenyl branched poly(p-terphenyl-piperidine) (h-PTP-BiAz-n), the application provides a synthesis path diagram of 6,6'-bi-azulenyl branched poly(p-terphenyl-piperidine) (h-PTP-BiAz-n), as shown in Figure 2, which is a synthesis path diagram of 6,6'-bi-azulenyl branched poly(p-terphenyl-piperidine) (h-PTP-BiAz-n) provided by the application.

[0096] (3) Preparation of azulenyl branched poly(aryl-piperidine) anion exchange membrane:

[0097] h-PTPE-BiAz-1 (1 g) was dissolved in 30 mL of DMSO, the polymer solution was filtered through a 0.45 μm polytetrafluoroethylene filter membrane, and cast on a clean glass plate. Subsequently, the solution was evaporated at 80°C for 12 h, at 120°C for 12 h, and vacuum dried at 120°C for 24 h to completely remove the residual solvent. The I-type membrane was peeled off from the glass plate. Ion exchange was carried out in 1M KCl solution at 80°C for 12 h, followed by washing with deionized water for 3 times to remove residual salt, to obtain Cl - type membrane. Ion exchange was carried out in 1M KOH solution at 80°C for 12 h, followed by washing with deionized water for 3 times under nitrogen atmosphere, to obtain OH - type membrane, i.e. azulenyl branched poly(aryl-piperidine) h-PTP-BiAz-1 anion exchange membrane.

[0098] Example 2

[0099] The present example 2 provides a preparation method of azulenyl branched poly(p-terphenyl-piperidine) anion exchange membrane, i.e. 6,6'-bi-azulenyl branched poly(p-terphenyl-piperidine) (h-PTP-BiAz-2) anion exchange membrane, and the specific steps are as follows:

[0100] The 6,6'-bi-azulenyl branched poly(p-terphenyl-piperidine) (h-PTP-BiAz-2) anion exchange membrane was prepared according to the method of example 1, except that the molar content of BiAz monomer in the form of percentage was 2.

[0101] In order to verify the performance of the azulenyl branched poly(aryl-piperidine) anion exchange membrane prepared in example 1, the performance test of the azulenyl branched poly(aryl-piperidine) anion exchange membrane was carried out, and the test results are shown in the figure.

[0102] The test shows that the h-PTP-BiAz-1 anion exchange membrane prepared in examples 1-2 has an OH -The conductivity is 154 mS / cm, the ion exchange capacity is 2.4 mmol / g, the swelling ratio is 54%, the tensile strength is 55 MPa, the elongation at break is 10%, and the alkaline stability is maintained for 1000 h in 1M KOH at 80°C. At the same time, the h-PTP-BiAz-2 anion exchange membrane maintains OH - The conductivity is 168 mS / cm, the ion exchange capacity is 2.4 mmol / g, the swelling ratio is 42%, the tensile strength is 72 MPa, the elongation at break is 13%, and the alkaline stability is maintained for 1000 h in 1M KOH at 80°C, indicating that the homogeneous anion exchange membrane prepared in this embodiment has smaller swelling, suitable ion conductivity and anion exchange capacity, and good mechanical properties; and as the amount of azulene monomer increases, the OH - The conductivity increases, the swelling ratio decreases, and the mechanical properties are enhanced.

[0103] Comparative Example 1

[0104] Comparative Example 1 provides a method for preparing a poly(p-terphenyl-piperidine) anion exchange membrane (PTP), and the specific steps are as follows:

[0105] The poly(p-terphenyl-piperidine) anion exchange membrane (PTP) is prepared according to the method of Example 1, except that 6,6'-azulene monomer is not added.

[0106] Tests show that the poly(p-terphenyl-piperidine) anion exchange membrane prepared in Comparative Example 1 maintains OH - The conductivity is 110 mS / cm, the anion exchange capacity is 2.1 mmol / g, the swelling ratio is 55%, the tensile strength is 42 MPa, the elongation at break is 17%, and the alkaline stability is maintained for 728 h in 1M KOH at 80°C.

[0107] Figure 3 is a comparison of the mechanical properties of the azulene-branched poly(p-terphenyl-piperidine) anion exchange membranes prepared in Examples 1 and 2 and the poly(p-terphenyl-piperidine) anion exchange membrane prepared in Comparative Example 1. Figure 4 is the swelling ratio test results of the azulene-branched poly(p-terphenyl-piperidine) anion exchange membranes prepared in Examples 1 and 2. Figure 5 is the anion exchange membrane electrolysis water test results of the azulene-branched poly(p-terphenyl-piperidine) anion exchange membranes prepared in Examples 1 and 2.

[0108] As can be seen from Figure 3, the azulene-branched poly(p-terphenyl-piperidine) anion exchange membranes prepared in Examples 1 and 2 have enhanced mechanical properties compared to the poly(p-terphenyl-piperidine) anion exchange membrane prepared in the comparative example.

[0109] As shown in Figure 4, the azulene branched poly(p-terphenyl-piperidine) anion exchange membranes prepared in Examples 1 and 2 have lower swelling ratio than the poly(p-terphenyl-piperidine) anion exchange membranes prepared in the comparative examples.

[0110] As shown in Figure 5, the azulene branched poly(p-terphenyl-piperidine) anion exchange membranes prepared in Examples 1 and 2 have enhanced performance in water electrolysis than the poly(p-terphenyl-piperidine) anion exchange membranes prepared in the comparative examples.

[0111] The results show that the performance of the anion exchange membranes prepared in the comparative examples is significantly lower than that of the anion exchange membranes prepared in Examples 1 and 2.

[0112] The above description is merely a specific implementation of the present application. However, the scope of protection of the present application is not limited in this way. Any person skilled in the art can easily think of changes or replacements within the technical scope disclosed in the present application, and all such changes or replacements should be covered within the scope of protection of the present application. Therefore, the scope of protection of the present application should be subject to the scope of protection of the claims.

Claims

1. An azulenyl branched poly(aryl-piperidine) anion exchange membrane characterized by, The azulenyl branched poly(aryl-piperidine) anion exchange membrane contains an azulenyl branched poly(aryl-piperidine) polymer having the following structure: wherein R is an aromatic group, A is an azulenyl branched group, a is an arbitrary integer equal to or greater than 0, and b is an arbitrary integer equal to or greater than 1.

2. The azulenyl branched poly(aryl-piperidine) anion exchange membrane according to claim 1, characterized in that, The R is at least one of the following structures: wherein R1 and R2 are one or more of H atoms, aliphatic groups, or aromatic groups.

3. The azulenyl branched poly(aryl-piperidene) anion exchange membrane of claim 1, wherein, The A is at least one of the following structures:

4. A process for the preparation of the azolyl branched poly(aryl-piperidine) anion exchange membrane according to any one of claims 1 to 3, characterized in that, The method comprises: (1) preparing an azulenyl branched poly(aryl-piperidine) precursor: dissolving aromatic monomers, azulenyl branched monomers, and N-methyl-4-piperidone in a first organic solvent, adding trifluoroacetic acid and trifluoromethanesulfonic acid, and collecting the azulenyl branched poly(aryl-piperidine) precursor after reaction; (2) preparing a cationized azulenyl branched poly(aryl-piperidine): dissolving the azulenyl branched poly(aryl-piperidine) precursor in a second organic solvent, adding potassium carbonate and iodomethane, and collecting the cationized azulenyl branched poly(aryl-piperidine) after light-avoiding reaction and purification treatment with ethyl acetate; (3) preparing an azulenyl branched poly(aryl-piperidine) anion exchange membrane: dissolving the cationized azulenyl branched poly(aryl-piperidine) in a third organic solvent, collecting Cl - type thin film, subjecting the Cl - type thin film to ion exchange, obtaining OH - type membrane, and after purification treatment, collecting the azulenyl branched poly(aryl-piperidine) anion exchange membrane.

5. The method for preparing azulene-based branched poly(aryl-piperidine) anion exchange membrane according to claim 4, characterized by, the molar ratio of the aromatic monomers to the azulenyl branched monomers is 0-99:1; and / or the molar ratio of the sum of the addition amounts of the azulenyl branched monomers and the aromatic monomers to the addition amount of the N-methyl-4-piperidone is 1:0.9-1.

2.

6. The method for preparing azulene-based branched poly(aryl-piperidine) anion exchange membrane according to claim 4, characterized by, the molar ratio of the N-methyl-4-piperidone to the trifluoroacetic acid is 1:0.8-1.2; and / or the molar ratio of the N-methyl-4-piperidone to the trifluoromethanesulfonic acid is 1:8-12.

7. The method for preparing azulene-based branched poly(aryl-piperidine) anion exchange membrane according to claim 4, characterized by, the first organic solvent is one or more of chloroform, dichloromethane, carbon tetrachloride, dichloroethane, and 1,1,2,2-tetrachloroethane.

8. The method for preparing azulenyl branched poly(aryl-piperidine) anion exchange membrane according to claim 4, characterized by, the second organic solvent is one or more of acetonitrile, tetrahydrofuran, N-methylpyrrolidone, dimethyl sulfoxide, N,N-dimethylacetamide, N,N-dimethylformamide, and sulfolane.

9. Use of the azulenyl branched poly(aryl-piperidine) anion exchange membrane according to any one of claims 1-3 and the azulenyl branched poly(aryl-piperidine) anion exchange membrane prepared by the method according to any one of claims 4-7 in preparing alkaline fuel cells and alkaline electrolytic cells.

10. Use according to claim 9, characterized in that, The azulene-based branched poly(p-terphenyl-piperidine) anion exchange membrane has an OH - The conductivity is at least 150 mS / cm.

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