Polymers containing triazolyl aether branches, methods of preparation and uses thereof

Abstract

The application provides a polymer containing a triazole cryptand branched chain, which contains a 1,2,3-triazole cryptand branched chain. The polymer is prepared by a click reaction of a [2.2.2]-cryptand compound containing an alkyne group substituent and an azide polymer, and then is hot-pressed into a film to obtain an anion exchange film with a cryptand group. The anion exchange film provided by the application does not involve groups such as quaternary phosphonium and quaternary ammonium used by most anion exchange films, avoids degradation problems in a strong alkali environment, and has the advantages of high ion conductivity and good alkali stability.

Description

Technical Field

[0001] This invention belongs to the field of fuel cell technology, specifically relating to a polymer containing triazole cryptether side chains, and its application in the preparation of anion exchange membranes. Background Technology

[0002] Hydrogen-based fuel cell technology converts chemical energy into electrical energy. It effectively meets humanity's growing energy demands while producing relatively low environmental pollution, making it a crucial pathway to achieving carbon neutrality. Hydrogen-based fuel cells primarily include anion exchange membrane (AEMFC) cells and proton exchange membrane (PEMFC) cells. Among these, AEMFCs have attracted widespread attention due to their lower cost and better potential for scalability compared to PEMFCs, which require precious metal catalysts (such as platinum). AEMFCs, on the other hand, can achieve energy conversion using more affordable bipolar plates and lower-cost polymers. Currently, AEMFCs are still in the early stages of development, particularly requiring improvements in the stability and heat resistance of the anion exchange membrane (AEM), which determines their performance.

[0003] An AEMFC consists of an anode, a cathode, and an anion exchange membrane (AEM). The efficient and rapid operation of an AEMFC depends on the performance of the AEM. The AEM mainly consists of a polymer backbone, covalently attached cationic functional groups, and mobile anions. The cationic functional group is OH... – The ionic conductivity of AEMs is a crucial conductive medium, thus significantly influencing their ion exchange capacity and ionic conductivity. The trade-off between ionic conductivity and water absorption rate limits the applicability of AEMs in AEMFCs.

[0004] Currently, the cationic functional groups on anion exchange membranes (AEMs) have the following problems: 1) Organic cations are easily attacked by hydroxide ions and degraded under alkaline conditions; 2) Transition metal ligand complexes have good alkaline stability as cationic functional groups, but as transition metals, their redox stability is poor; 3) Crown ethers with cavity structures can complex alkali metal cations as cationic functional groups, exhibiting excellent alkaline stability. However, the complexation constant of crown ethers complexing alkali metal cations is small, so the cations are easily released, leading to a decrease in the conductivity of AEMs during practical applications. Therefore, it is necessary to develop new materials with good alkaline stability. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a polymer containing triazole cryptether branches. The three-dimensional cavity structure of the cryptether in this polymer can bind to various cations, such as alkali metal cations, alkaline earth metal cations, and lanthanides, exhibiting stronger complexing ability. The exchange membrane prepared from this polymer exhibits high ionic conductivity, excellent alkaline stability, and good flexibility, demonstrating good stability when used as an anion exchange membrane, thus completing this invention.

[0006] A first aspect of this invention aims to provide a polymer containing a triazole cryptether branch, wherein the triazole cryptether branch is selected from 1,2,3-triazole cryptether branches, and preferably, the triazole cryptether branch is:

[0007]

[0008] The second aspect of this invention aims to provide a polymer containing a triazole cryptether branch, which is prepared by a click reaction of a [2.2.2]-cryptether compound containing an alkynyl substituent with an azide polymer.

[0009] Preferably, the polymer containing triazole cavitary ether branches has the following structural units:

[0010]

[0011]

[0012] Where x is 1-7, preferably 1-5, more preferably 1-3, and x is an integer.

[0013] A third aspect of the present invention aims to provide a method for preparing the polymer containing triazole cryptether branches, wherein the method prepares the polymer containing triazole cryptether branches by clicking a [2.2.2]-cryptether compound containing an alkynyl substituent with an azide polymer.

[0014] The [2.2.2]-cavitary ether compounds containing alkynyl substituents are prepared by a method comprising the following steps:

[0015] Step 1: React an alkynyl diol with a 2-haloethanol ether protected by an umami group to remove the umami protection and obtain intermediate product I;

[0016] Step 2: Add p-toluenesulfonyl chloride to a solution containing intermediate product I and react to obtain intermediate product II;

[0017] Step 3: React intermediate product II with diaza-18-crown ether-6 to prepare [2.2.2]-cavitary ether compounds containing alkynyl substituents.

[0018] The fourth aspect of this invention aims to provide the use of the polymer containing triazole cryptether branches for the preparation of anion exchange membranes in anion fuel cells.

[0019] The polymer containing triazole cavitary ether side chains provided in this invention has the following beneficial effects:

[0020] (1) Cavitation ethers are three-dimensional derivatives of crown ethers, but unlike crown ethers, the three-dimensional cavity structure of cavitation ethers can combine with a variety of cations, such as alkali metal cations, alkaline earth metal cations, and lanthanides. Compared with crown ethers, they have a stronger complexing ability. In addition, cavitation ethers themselves have good basic stability, which can greatly enhance the stability of anion exchange membranes.

[0021] (2) In this invention, triazole cryptether is grafted onto the polymer backbone via a click reaction. A rationally designed synthetic route and method for triazole cryptether are employed, enabling its successful preparation and providing a prerequisite for subsequent polymer preparation. The preparation method has low production costs and is safe and versatile.

[0022] (3) This invention grafts alkynyl cryptethers onto the polymer backbone via a click reaction, which can be a polyethylene backbone, a polyetherketone backbone, an aryl backbone, etc., to prepare a polymer containing a cryptether structure. This polymer has great application potential in anion exchange membrane batteries, fluorescent probes, and water electrolysis.

[0023] (4) The obtained anion exchange membrane has good conductivity. Based on the high efficiency of the click reaction between alkynyl cryptether and azide polymer, anion exchange membranes with high cryptether content can be synthesized. The prepared anion exchange membrane has good stability and has potential industrial application prospects in anion exchange membrane batteries. Attached Figure Description

[0024] Figure 1 The infrared spectrum of the polymer prepared in Example 6 of the present invention is shown.

[0025] Figure 2 The graph shows the trend of OH- ion conductivity of the anion exchange membranes prepared by treating PECryp7 and PECryp13 obtained in Example 6 of this invention as a function of temperature.

[0026] Figure 3 The graph shows the change in membrane conductivity over time for PECryp7-BaCl2, PECryp13-BaCl2 and commercially available PiperION-A80 prepared in Experimental Example 1 of this invention at 40°C and 60°C. Detailed Implementation

[0027] The present invention will now be described in detail through specific embodiments, and the features and advantages of the present invention will become clearer and more explicit with these descriptions.

[0028] This invention provides a polymer containing triazole cryptether branches. The three-dimensional cavity structure of the cryptether in this polymer can bind to various cations, such as alkali metal cations, alkaline earth metal cations, and lanthanides, exhibiting stronger complexing ability. The exchange membrane prepared from this polymer exhibits high ionic conductivity, excellent alkaline stability, and good flexibility. It demonstrates good stability when used as an anion exchange membrane and shows potential for industrial application in anion fuel cells.

[0029] The first aspect of this invention provides a polymer containing a triazole cryptether branch, wherein the triazole cryptether branch is selected from 1,2,3-triazole cryptether branches, and preferably, the triazole cryptether branch is:

[0030]

[0031] A second aspect of the present invention provides a polymer containing a triazole cryptether branch, which is prepared by a click reaction of a [2.2.2]-cryptether compound containing an alkynyl substituent with an azide polymer.

[0032] The [2.2.2]-cavitary ether containing an alkynyl substituent is selected from compounds having the following structure:

[0033]

[0034] Preferably, the [2.2.2]-cavitary ether of the alkynyl substituent is:

[0035]

[0036] Where y is 1-7, preferably 1-5, more preferably 1-3, and y is an integer.

[0037] The azide polymer is selected from polymers having the following structural units:

[0038] The azide polymer may also be selected from copolymers containing the following structural units:

[0039]

[0040]

[0041] Where x is 1-7, preferably 1-5, more preferably 1-3, and x is an integer.

[0042] Preferably, the polymer containing triazole cavitary ether branches has the following structural units:

[0043]

[0044]

[0045] Where x is 1-7, preferably 1-5, more preferably 1-3, and x is an integer.

[0046] The third aspect of the present invention also provides a method for preparing the polymer containing triazole cavitary ether branches, wherein the method prepares the polymer containing triazole cavitary ether branches by clicking reaction of a [2.2.2]-cavitary ether compound containing an alkynyl substituent with an azide polymer.

[0047] The click reaction is a cycloaddition reaction of an azide group and an alkynyl group under a copper catalyst. The copper catalyst is selected from copper salts, preferably cuprous iodide and / or cuprous chloride, and more preferably cuprous iodide.

[0048] Preferably, a ligand compound, selected from organic amines, is also added to the click reaction, preferably triethylamine and / or N,N-diisopropylethylamine (DIPEA). Organic amines can form complexes with copper salts, which is beneficial for the click reaction.

[0049] Preferably, a reducing agent is also added to the click reaction to prevent the formation of oxidative coupling products. The reducing agent is selected from one or more amino acids and ascorbic acid salts, preferably ascorbic acid salts, such as sodium ascorbate.

[0050] The reaction is carried out in a solvent selected from one or more of ether solvents, ketone solvents and sulfone solvents, preferably one or more of tetrahydrofuran, methyl isobutyl ketone, cyclohexanone, and dimethyl sulfoxide, more preferably tetrahydrofuran.

[0051] The molar ratio of the [2.2.2]-catechol ether compound containing an alkynyl substituent to the azide polymer is 1:(0.6-1.8), preferably 1:(0.8-1.5), and more preferably 1:(1-1.2).

[0052] The molar ratio of the [2.2.2]-catechol ether compound containing an alkynyl substituent to the copper catalyst is 1:(0.02-1), preferably 1:(0.03-0.08), more preferably 1:(0.03-0.05), for example 1:0.04.

[0053] The molar ratio of the copper catalyst to the ligand compound is 1:(1.2-2.8), preferably 1:(1.5-2.5), and more preferably 1:(1.8-2.2).

[0054] The molar ratio of the copper catalyst to the reducing agent is 0.0:(0.3-0.8), preferably 0.02:(0.3-0.7), and more preferably 0.02:(0.4-0.6).

[0055] The molar volume ratio of the [2.2.2]-caecinate compound containing an alkynyl substituent to the solvent is 0.5 mmol:(4-18) mL, preferably 0.5 mmol:(6-15) mL, and more preferably 0.5 mmol:(8-12) mL.

[0056] The reaction temperature is 50-110℃, preferably 60-100℃, more preferably 70-90℃; the reaction time is 12-30h, preferably 14-25h, more preferably 16-20h.

[0057] After the reaction was complete, the crude product precipitated from the reaction solution. The precipitated crude polymer product was cut into small pieces, ultrasonically washed with water, acid-washed, adjusted to neutral, filtered, washed and dried to obtain a polymer containing triazole cryptether branches.

[0058] The pickling process involves washing with an inorganic acid at a controlled temperature for 10-20 hours, preferably 12-15 hours, to remove residual copper ions. The inorganic acid is selected from dilute sulfuric acid or dilute hydrochloric acid, preferably dilute hydrochloric acid; the controlled temperature is 40-80°C, preferably 45-75°C, and more preferably 50-70°C.

[0059] The washing and drying process involves washing in alcoholic solvents and / or ether solvents followed by drying, such as washing with anhydrous ethanol and anhydrous diethyl ether in sequence.

[0060] The [2.2.2]-cavitary ether compounds containing alkynyl substituents are prepared by a method comprising the following steps:

[0061] Step 1: Nucleophilic substitution reaction is carried out using an alkynyl diol and a 2-haloethanol ether protected by uranium to remove uranium protection and obtain intermediate product I;

[0062] The alkynyl diol is selected from diol compounds having the following structures:

[0063] Preferred

[0064] Where y is 1-7, preferably 1-5, more preferably 1-3, and if it is 1, y is an integer.

[0065] The alkynyl diol can be commercially available or prepared in-house.

[0066] The alkynyl-containing diol The reaction of acetone glycerol and haloalkynes in the presence of an alkali metal hydride catalyst yields a diol containing an alkali group, which is then reacted under acidic conditions. The alkali metal hydride is selected from potassium hydride or sodium hydride, preferably sodium hydride.

[0067] The haloacetylene is 3-halopropyne or 4-halophenylacetylene, and the halogenation is selected from iodination, bromination or chlorination.

[0068] The reaction is carried out in a solvent selected from one or more of halogenated hydrocarbon solvents, amide solvents, ether solvents and aromatic hydrocarbon solvents, preferably selected from one or more of dichloromethane, N,N-dimethylformamide, tetrahydrofuran and toluene, and more preferably N,N-dimethylformamide.

[0069] The molar volume ratio of the acetone glycerol to the solvent is 20 mmol:(25-55) mL, preferably 20 mmol:(30-50) mL, and more preferably 20 mmol:(35-45) mL.

[0070] The molar ratio of acetone glycerol to haloacetylene is 20:(14-34), preferably 20:(18-30), and more preferably 20:(22-26).

[0071] The molar ratio of acetone glycerol to alkali metal hydride is 20:(30-55), preferably 20:(35-50), and more preferably 20:(40-45).

[0072] The reaction temperature is 15-35℃, preferably 20-30℃, and the reaction time is 18-28h, preferably 20-25h.

[0073] Preferably, acetone glycerol is first added to a reaction solvent containing alkali metal hydrides, and the reaction is stirred until complete. Then, haloalkynes are slowly added under ice bath conditions, such as dropwise, and the temperature is raised to carry out the reaction.

[0074] After the reaction was completed, deionized water was added dropwise to the reaction solution under ice-water bath conditions until no more bubbles were produced. Then, NaOH aqueous solution was added, and the mixture was extracted three times with anhydrous diethyl ether. The organic phases were combined, backwashed with saturated sodium chloride, and the organic phase was collected. The mixture was dried over anhydrous sodium sulfate, filtered, and rotary evaporated to obtain the process product.

[0075] The product of the process is added to an alcohol solvent, followed by an inorganic acid. The mixture is stirred and reacted at 20-30°C for 20-28 hours. After the reaction, the product is washed with alkali to remove the solvent, dissolved in dichloromethane, filtered to remove impurities, and then purified by rotary evaporation to obtain a diol containing an alkynyl group. The inorganic acid is selected from hydrochloric acid and / or sulfuric acid, preferably hydrochloric acid.

[0076] In this invention, the 2-haloethanol ether protected by uranium is selected from 2-(2-bromoethoxy)tetrahydropyran and / or 2-[(2-bromoethoxy)methyl]tetrahydrofuran, preferably 2-(2-bromoethoxy)tetrahydropyran.

[0077] The molar ratio of the alkynyl-containing diol to the 2-haloethanol ether protected by uman is 1:(2-4.0), preferably 1:(2.3-3.6), and more preferably 1:(2.5-3.2).

[0078] The nucleophilic substitution reaction is carried out in the presence of a catalyst selected from alkali metal hydrides, preferably sodium hydride and / or potassium hydride, more preferably sodium hydride. The molar ratio of the alkynyl-containing diol to the catalyst is 1:(3-5), preferably 1:(3.2-4.5), more preferably 1:(3.5-4.0).

[0079] The nucleophilic substitution reaction is carried out in a solvent selected from one or more of halocarbon solvents, amide solvents, ether solvents and aromatic hydrocarbon solvents, preferably selected from one or more of dichloromethane, N,N-dimethylformamide, tetrahydrofuran and toluene, and more preferably N,N-dimethylformamide.

[0080] The molar volume ratio of the alkynyl diol to the solvent is 12 mmol:(6-25) mL, preferably 12 mmol:(8-20) mL, and more preferably 12 mmol:(10-15) mL.

[0081] Preferably, under conditions of -5 to 8°C, a diol solution containing an alkynyl group is added to the catalyst solution, stirred, and then a 2-haloethanol ether protected by an umanoyl group is added, followed by heating to carry out the reaction. The substitution reaction temperature is 15 to 30°C, preferably 20 to 25°C; the reaction time is 18 to 30 hours, preferably 22 to 26 hours.

[0082] After the reaction was complete, deionized water was added dropwise under ice bath conditions until no more bubbles emerged; the mixture was extracted three times with anhydrous diethyl ether, the organic phases were combined, backwashed with saturated sodium chloride, and the organic phase was collected; the mixture was dried over anhydrous sodium sulfate, filtered, and rotary evaporated; the residue was purified by rapid silica gel column chromatography (using a mixture of petroleum ether and ethyl acetate as the mobile phase) to give a product with the following structure and protected by an alkyl nitrate group:

[0083] Preferred

[0084] Where R is a nan protecting group, such as...

[0085] The removal of uranium protection was carried out in the presence of a catalyst in an alcohol solvent at a controlled temperature. After the reaction was completed, the reaction solution was cooled to room temperature, the solvent was evaporated, and the solution was purified by column chromatography to obtain intermediate product I.

[0086] The catalyst is selected from acid compounds, preferably one or more of p-toluenesulfonic acid, p-toluenesulfonic acid pyridine, and heteropoly acids, and more preferably p-toluenesulfonic acid pyridine.

[0087] The molar ratio of the product with uranyl protection to the catalyst is (4-18):1, preferably (6-15):1, and more preferably (8-12):1.

[0088] The alcohol solvent is selected from alkyl alcohols, preferably one or more of methanol, propanol, n-butanol and isobutanol, and more preferably methanol. The molar volume ratio of the product with alkyl alkyl group protection to the alcohol solvent is 6 mmol:(15-45) mL, preferably 6 mmol:(20-40) mL, and more preferably 6 mmol:(25-35) mL.

[0089] The deprotection reaction temperature is 45-75℃, preferably 55-65℃, and the reaction time is 18-30h, preferably 22-26h.

[0090] The intermediate product I is selected from compounds having the following structures:

[0091] Preferred

[0092] Step 2: Add p-toluenesulfonyl chloride to a solution containing intermediate product I and react to obtain intermediate product II;

[0093] Intermediate product I is added to a solvent, wherein the solvent is selected from one or more of halogenated hydrocarbons, amides, ethers, and aromatic hydrocarbons, preferably from one or more of halogenated hydrocarbons, and more preferably from halogenated hydrocarbons.

[0094] The molar volume ratio of intermediate product I to solvent is 6 mmol:(15-45) mL, preferably 6 mmol:(20-40) mL, and more preferably 6 mmol:(25-35) mL.

[0095] The molar ratio of intermediate product I to p-toluenesulfonyl chloride is 6:(7-30), preferably 6:(10-25), and more preferably 6:(13-20).

[0096] The reaction in step 2 is carried out under alkaline conditions, and an organic amine is added to the reaction solution, preferably one or more of diethylamine, triethylamine, ethylenediamine, and hexamethylenediamine, more preferably triethylamine. The molar ratio of intermediate product I to the organic amine is 6:(20-45), preferably 6:(25-40), more preferably 6:(30-35).

[0097] After the reaction was complete, the reaction solution was added with water and extracted three times with dichloromethane. The organic phases were combined, dried with a solid desiccant, filtered, and the solvent was rotary evaporated. The crude product was purified by rapid silica gel column chromatography using a mixture of petroleum ether and ethyl acetate as the mobile phase.

[0098] The intermediate product II is selected from compounds having the following structures:

[0099] Preferred Where Ts is

[0100] Step 3: React intermediate product II with diaza-18-crown ether-6 to prepare [2.2.2]-cavitary ether compounds containing alkynyl substituents.

[0101] The reaction in step 3 is carried out in a solvent, which is selected from one or more of nitrile solvents, alcohol solvents, ether solvents and amide solvents, preferably one or more of nitrile solvents, and more preferably acetonitrile.

[0102] The molar volume ratio of intermediate product II to solvent is 3.4 mmol:(50-110) mL, preferably 3.4 mmol:(60-100) mL, and more preferably 3.4 mmol:(70-90) mL.

[0103] The molar ratio of intermediate product II to diaza-18-crown ether-6 is 1:(0.6-1.8), preferably 1:(0.8-1.5), and more preferably 1:(1-1.2).

[0104] The reaction in step 3 is carried out under alkaline conditions, and an inorganic alkaline substance is added to the reaction solvent. The substance is selected from one or more of carbonates, phosphates and bicarbonates, preferably carbonates, such as sodium carbonate or potassium carbonate.

[0105] The molar ratio of intermediate product II to inorganic alkaline substance is 3.4:(9-29), preferably 3.4:(12-24), and more preferably 3.4:(15-19).

[0106] The reaction temperature is 70-105℃, preferably 85-95℃, and the reaction time is 20-40h, preferably 25-35h.

[0107] After the reaction was completed, the reaction solution was cooled to room temperature, and the lower layer liquid was collected by diatomaceous earth filtration. The lower layer liquid was then purified by rotary evaporation and rapid silica gel column chromatography (the mobile phase was a mixture of chloroform and anhydrous ethanol) to obtain [2.2.2]-cavitary ether compounds containing alkynyl substituents.

[0108] In current research on cryptethers, benzo-fused structures are a common strategy for mounting functional groups onto cryptethers, but the increased rigidity leads to a decrease in binding strength. Therefore, in this invention, alkyne functionalization of [2.2.2]-cryptethers is the synthetic target, and copper-catalyzed azido-alkyne cycloaddition (CuAAC) reaction (click reaction) is used for linkage.

[0109] In this invention, acetone glycerol and haloalkynes are used as raw materials to obtain alcohol products. To extend the carbon chain, an um-protected 2-haloethanol ether is added to react and obtain the process product. Further, the um-protection is removed with p-toluenesulfonic acid pyridine in methanol solution to obtain intermediate product I. This intermediate I then reacts with p-toluenesulfonyl chloride to obtain a bis-p-toluenesulfonyl-substituted alkynyl intermediate, i.e., intermediate product II, ensuring minimal solvent residue. Finally, intermediate product II reacts with diaza-18-crown-6 ether in a solvent to obtain a [2.2.2]-cavitary ether compound containing an alkynyl substituent.

[0110] The present invention employs a rationally designed synthetic route for the aforementioned [2.2.2]-cryptoether compounds containing alkynyl substituents, yielding polymers containing triazole cryptoether branches. The designed route is rational, with high synthetic yields and few impurities. The obtained polymers containing triazole cryptoether branches can be used to prepare anion exchange membranes in anion fuel cells.

[0111] The fourth aspect of the invention also provides the use of the polymer containing triazole cryptether branches for the preparation of anion exchange membranes in anion fuel cells.

[0112] The synthetic route of this invention successfully prepared a polymer containing triazole cryptethers. The preparation method is low-cost, safe, and versatile. By grafting triazole cryptethers onto the polymer backbone via a click reaction, a polymer containing triazole cryptether side chains was successfully obtained. Based on the high efficiency of the click reaction between triazole cryptethers and azide-containing polymers, anion exchange membranes with high cryptether content can be synthesized. The anion exchange membrane prepared from the obtained polymer exhibits good conductivity and basic stability. Due to the high basic stability of the cryptether group, the prepared anion exchange membrane containing the cryptether group also possesses excellent basic stability.

[0113] Example

[0114] Example 1

[0115] Under ice-water bath conditions, sodium hydride (NaH) (1.6 g, approximately 40 mmol), acetone glycerol (2.6 g, approximately 20 mmol), and N,N-dimethylformamide (DMF, 40 mL) were added sequentially to a 100 mL three-necked round-bottom flask, and the mixture was magnetically stirred for 2 hours. Then, under ice-water bath conditions, 3-bromopropyne (1.8 mL, approximately 24 mmol) was slowly added dropwise to the flask, and the mixture was magnetically stirred at 25 °C for 24 hours. The reaction progress was confirmed by TLC. After the reaction was confirmed to be complete, deionized water was added dropwise to the reaction mixture under ice-water bath conditions until no more bubbles emerged. Then, 2 M NaOH aqueous solution (30 mL) was added, and the mixture was extracted three times with anhydrous diethyl ether. The organic phases were combined, backwashed once with saturated sodium chloride, and collected. The organic phase was dried over anhydrous sodium sulfate, filtered, and rotary evaporated to obtain the process product.

[0116] The product (approximately 20 mmol) was then placed in a 100 mL three-necked round-bottom flask, and concentrated hydrochloric acid (36 wt%–38 wt%, 4 mL) and methanol (MeOH, 40 mL) were added. The mixture was magnetically stirred at 25 °C for 24 hours, and the reaction progress was confirmed by TLC. After the reaction was confirmed to be complete, the pH of the reaction solution was adjusted to alkaline with 6 M NaOH solution, and the solvent was then evaporated. Dichloromethane was added to the reaction flask to dissolve the crude product, which was dried over anhydrous sodium sulfate. Impurities were filtered off, and dichloromethane was removed by rotary evaporation. The residue was purified by rapid silica gel column chromatography (mobile phase: petroleum ether: ethyl acetate = 1:1) to give 1.5 g of alkynyl-containing diol product 1, yield: 77%.

[0117] The main synthetic route is as follows:

[0118]

[0119] The NMR characterization data are as follows:

[0120] 1 H NMR (400MHz, Chloroform-d) δ4.19 (d, J = 2.4Hz, 2H), 3.90–3.80 (m, 1H), 3.71 (dd, J = 11.5, 3.9Hz, 1H), 3.67–3.54 (m, 3H), 2.46 (t, J = 2.4Hz, 1H).

[0121] 13 C NMR(101MHz,Chloroform-d)δ79.4,75.1,71.2,70.8, 63.8,58.6.

[0122] Example 2

[0123] Sodium hydride (1.8 g, approximately 46 mmol) and DMF (40 mL) were added to a 100 mL three-necked round-bottom flask. Product 1 (1.5 g, approximately 12 mmol) obtained in Example 1 was dissolved in 10 mL of DMF solution and then slowly added dropwise to the flask under ice-water bath conditions. After magnetic stirring for 2 hours, tetrahydropyranyl ether of 2-bromoethanol (7.2 g, approximately 35 mmol) was added under ice-water bath conditions, and the mixture was stirred at 25 °C for 24 hours. The reaction progress was confirmed by TLC. After the reaction was confirmed to be complete, deionized water was added dropwise to the reaction mixture under ice-water bath conditions until no more bubbles were observed. The mixture was extracted three times with anhydrous diethyl ether, and the organic phases were combined. The mixture was backwashed once with saturated sodium chloride, and the organic phase was collected, dried over anhydrous sodium sulfate, filtered, and rotary evaporated. The residue was purified by rapid silica gel column chromatography (petroleum ether: ethyl acetate = 2:1) to give 2.2 g of product 2, yield: 70%.

[0124] The main synthetic route is as follows:

[0125]

[0126] The NMR characterization data are as follows:

[0127] 1 H NMR(400MHz,Chloroform-d)δ4.63(q,J=3.3Hz,2H), 4.18(d,J=2.4Hz,2H),3.93–3.75(m,7H),3.73–3.55(m,8H), 3.51–3.48(m,2H),2.40(t,J=2.4Hz,1H),1.90–1.77(m,2H), 1.76–1.65(m,2H),1.63–1.43(m,8H).

[0128] 13 C NMR(101MHz,Chloroform-d)δ99.0,98.9,98.8,78.4, 74.5,74.4,71.2,71.1,70.8,70.0,69.9,69.8,66.9,66.6,62.1,58.6,30.6,25.5,19.5,19.4.

[0129] Example 3

[0130] In a 100 mL three-necked round-bottom flask, product 2 (2.2 g, approximately 6 mmol), pyridine 4-methylbenzenesulfonic acid (PPTS, 143.2 mg, approximately 0.6 mmol), and methanol (30 mL) were added sequentially. The mixture was magnetically stirred at 60 °C for 24 hours. The reaction progress was confirmed by TLC. After the reaction was confirmed to be complete, the reaction solution was cooled to room temperature, and the solvent was evaporated. The residue was then purified by rapid silica gel column chromatography (petroleum ether: ethyl acetate = 1:1) to give product 3 1.2 g, yield: 96%.

[0131] The main synthetic route is as follows:

[0132]

[0133] The NMR characterization data are as follows:

[0134] 1 H NMR (400MHz, Chloroform-d) δ4.16 (d, J = 2.4Hz, 2H), 3.75–3.66 (m, 7H), 3.62–3.55 (m, 6H), 3.14 (s, 2H), 2.44 (t, J = 2.4Hz, 1H).

[0135] 13 C NMR(101MHz,Chloroform-d)δ79.3,78.0,74.9,72.8, 71.95,71.1,69.6,61.7,61.4,58.5

[0136] Example 4

[0137] In a 100 mL three-necked flask, product 3 (1.2 g, approx. 6 mmol), dichloromethane (DCM, 30 mL), p-toluenesulfonyl chloride (TsCl, 3.1 g, approx. 17 mmol), 4-dimethylaminopyridine (0.06 g, approx. 0.6 mmol), and triethylamine (TEA, 4.6 mL, approx. 33 mmol) were added sequentially, and the mixture was stirred at 25 °C for 24 h. The reaction progress was confirmed by TLC. After the reaction was complete, the reaction mixture was added to water, extracted three times with dichloromethane, and the organic phases were combined, dried over anhydrous sodium sulfate, filtered, and rotary evaporated. The residue was purified by rapid silica gel column chromatography (petroleum ether:ethyl acetate = 2:1, v / v) to give product 4 2.9 g, yield: 81%.

[0138] The main synthetic route is as follows:

[0139]

[0140] The NMR characterization data are as follows:

[0141] 1H NMR(400MHz,Chloroform-d)δ7.81–7.72(m,4H), 7.41–7.32(m,4H),4.15–4.07(m,6H),3.83–3.76(m,2H), 3.67–3.60(m,2H),3.57–3.39(m,5H),2.47–2.38(m,7H).

[0142] 13 C NMR(101MHz,Chloroform-d)δ144.9,144.8,133.2, 133.1,129.9,129.8,127.9,127.8,79.5,78.5,74.7,71.3,69.6,69.51,69.2,68.9,68.1,58.6,21.6.

[0143] Example 5

[0144] In a 150 mL three-necked flask, diaza-18-crown-6 ether (0.9 g, approx. 3.4 mmol), anhydrous sodium carbonate (1.8 g, approx. 17.1 mmol), product 4 (1.8 g, approx. 3.4 mmol), and acetonitrile (80 mL) were added sequentially, and the mixture was stirred at 90 °C for 30 h. The reaction progress was confirmed by TLC. After the reaction was confirmed to be complete, the reaction mixture was cooled to room temperature, and the lower layer was collected by diatomaceous earth filtration. The lower layer was then rotary evaporated, and the residue was purified by rapid silica gel column chromatography (chloroform: anhydrous ethanol = 3:1) to give 1.8 g of product 5, yield: 52%.

[0145] The main synthetic route is as follows:

[0146]

[0147] The NMR characterization data are as follows:

[0148] 1 H NMR (400MHz, Chloroform-d) δ7.83(d,J=7.9Hz,2H), 7.09(d,J=7.9Hz,2H), 4.16(d,J=2.5Hz,2H), 3.77–3.44(m, 25H), 2.94–2.50 (m, 12H), 2.48 (t, J = 2.4Hz, 1H), 2.30 (s, 3H).

[0149] 13C NMR(101MHz,Chloroform-d)δ144.9,138.3,128.3, 126.4,79.5,76.6,75.1,70.1,68.9,68.8,68.8,68.7,68.7,68.6, 68.1,67.9,67.7,67.6,66.3,58.7,53.9,53.8,53.3,53.3,53.2, 53.1,21.4.

[0150] Example 6

[0151] The purchased ethylene-vinyl acetate copolymer (EVA) comes in two types: EVA (VA = 19wt% = 7mol%, melt index @190℃ = 16g / 10min, Sinopec Yanshan Petrochemical Company) and EVA (VA = 32wt% = 13mol%, melt index @190℃ = 43g / 10min, Aladdin Biochemical Technology Co., Ltd.).

[0152] In a 150 ml three-necked round-bottom flask, 6 g of ethylene-vinyl acetate copolymer (EVA) with a VA molar ratio of 7% or 13% and 100 ml of xylene were added. The EVA was dissolved at 110 °C. After complete dissolution, 25 ml of 2 M sodium hydroxide-ethanol solution was added dropwise to the reaction mixture. After complete addition, the reaction was carried out at 110 °C for 2 h, then cooled to room temperature. The crude product was precipitated in anhydrous ethanol, filtered, and the filtrate was washed with acid, water, and alcohol until neutral. The filtrate was then dried under vacuum at 50 °C to constant weight to obtain EVOH. EVOH7 (M) was obtained by hydrolyzing EVA with different VA contents. n =9750g mol -1 ) and EVOH13 (M n =9243 g mol -1 ).

[0153] In a 100 mL three-necked round-bottom flask, EVOH (EVOH7 or EVOH13, 1 mmol) and THF (20 mL) were added. The mixture was magnetically stirred at 50 °C until EVOH dissolved in THF. Triphenylphosphine (3 mmol) was then added, and the reaction was cooled to room temperature. Diphenyl azidophosphate (3 mmol) was added in an ice-water bath, and the mixture was stirred for 15 minutes. Then, diisopropyl azodicarbonate (3 mmol) and 2,6-di-tert-butyl-4-methylphenol (BHT, 50 mg) were added, and the mixture was magnetically stirred at 25 °C for 15 minutes. The temperature was then raised to 60 °C and magnetically stirred for 2 hours. The reaction mixture was then poured into methanol to precipitate the product, and the filtered material was sonicated three times with methanol. The desired polymer was dried under vacuum to obtain polyethylene azidophosphate (PE-N3-VA7 or PE-N3-VA13).

[0154] The main synthetic route is as follows:

[0155]

[0156] Where x = 0.07 or 0.13.

[0157] Add the prepared azide-coated polyethylene (PE-N3-VA7 or PE-N3-VA13, 0.5 mmol) to a 25 ml sealed tube, purge with nitrogen three times, add 10 mL of THF under a nitrogen atmosphere, and heat and stir to dissolve. Then add cuprous iodide (0.02 mmol), N,N-diisopropylethylamine (DIPEA, 0.04 mmol), compound 5 (0.5 mmol), and sodium ascorbate (100 mg), and magnetically stir at 80 °C for 18 hours. Cut the crude product precipitated from the solution into small pieces, wash with water and sonicate three times, then stir in 1 M HCl solution at 60 °C for 12 hours to remove residual copper ions. Add 1 M Na2CO3 solution to adjust the pH to neutral, filter, wash with anhydrous ethanol and anhydrous diethyl ether, and vacuum dry the polymer to obtain non-ionized polymer 6. A polymer with a pore ether content of 7 mol% is obtained from EVA with VA = 7 mol% via the following route: PECryp7. A polymer with a pore ether content of 13 mol% is obtained from EVA with VA = 13 mol% via the following route: PECryp13.

[0158] The polymer 6 has the following repeating units:

[0159]

[0160] The main synthetic route is as follows:

[0161]

[0162] Where x = 0.07 or 0.13.

[0163] Infrared data for PECryp13: 3446 (m), 2917 (s), 2849 (s), 1465 (m), 1355 (m), 1101 (s), 719 (m). The detailed infrared spectrum is as follows: Figure 1 As shown.

[0164] Experimental Example

[0165] Experimental Example 1

[0166] The polymers PECryp7 and PECryp13 obtained in Example 6 were hot-pressed into films. The films were then immersed in 1M HCl solution for 24 hours, washed with water, and then immersed in 1M LiOH solution for 24 hours, washed with water, to obtain non-ionic neutral films PECryp7 and PECryp13. The neutral films PECryp7 and PECryp13 were then immersed in 1M BaCl2 solution for 24 hours, washed with water three times for 30 minutes each time, to obtain PECryp7-BaCl2 and PECryp13-BaCl2, respectively.

[0167] Experimental Example 2

[0168] PECryp7-BaCl2 and PECryp13-BaCl2 were respectively soaked in 1M NaHCO3 solution for 24 hours, and washed with water three times for 30 minutes each time to obtain HCO3. – Sample membrane in the form of a sample.

[0169] The above HCO3 – The sample membrane was sandwiched within a BT-112 membrane conductivity cell and connected to an FD-HG temperature and humidity controller. (HCO3) – Conductivity measurements were performed for two hours to ensure membrane stability under the specified temperature and humidity conditions. A constant DC current of 400 μA was applied via an external electrode at 40°C and a relative humidity (RH) >98% at a nitrogen flow rate of 100 mL / min. The ionic resistance of the membrane was measured every 10 minutes using the four-probe EIS technique described above, and the in-plane conductivity of the membrane was then calculated using the following formula:

[0170]

[0171] In the formula, L is the distance between the two electrodes in the BT-112 membrane conductive cell (0.425 cm); R is the membrane resistance; W and d are the width and thickness of the sample, respectively.

[0172] Continuously measure the anionic conductivity until it reaches a stable value (resistance change <0.1kΩ within 3 hours), and record the OH- at 40℃. – The conductivity value was measured by continuously increasing the operating temperature of the test battery and the feed gas to 50℃ and 60℃ respectively while maintaining the RH level. The test results are as follows: Figure 2 As shown.

[0173] exist Figure 2 As can be seen, the conductivity gradually increases with increasing temperature, with PECryp13-Ba exhibiting a higher OH content at 60℃. – The conductivity can reach 81 mS / cm, proving that PECryp7 and PECryp13 films have high conductivity.

[0174] Experimental Example 3

[0175] The PECryp7-BaCl2 and PECryp13-BaCl2 membrane samples prepared in Example 1 were immersed in 15M KOH aqueous solution at 40℃ and 60℃, respectively. The samples were washed several times with deionized water at regular intervals to remove residual KOH, and then immersed in 1M BaCl2 aqueous solution for 24 hours. After washing with deionized water, the Cl- content was measured. – Conductivity. The alkaline stability of PECryp7-BaCl2 and PECryp13-BaCl2 membrane samples as anion exchange membranes was evaluated by using the relationship curves between ionic conductivity and immersion time.

[0176] When testing the alkali resistance of the above-mentioned PECryp7-BaCl2 and PECryp13-BaCl2 membrane samples as anion exchange membranes, the temperatures used were 40℃ and 60℃, respectively. At these temperatures, the membranes were immersed in a 15M KOH solution, and the change in ionic conductivity of the AEMs with immersion time was measured. Specific test results are as follows: Figure 3 As shown.

[0177] Depend on Figure 3 It can be seen that after soaking in strongly alkaline conditions for 1500 hours, the conductivity of PECryp7-BaCl2 and PECryp13-BaCl2 membranes remained stable at both 40℃ and 60℃. It is worth noting that placing the membrane in a 15M KOH solution under elevated temperature is one of the most stringent alkaline stability testing conditions currently available. When using the commercially available PiperION-A80 membrane, it was found that it almost completely lost its conductivity after only 15 days in a 15M KOH solution at 60℃. This indicates that the anion exchange membrane prepared from the polymer containing triazole cryptether side chains of this invention exhibits excellent alkaline stability.

[0178] The above results indicate that anion exchange membranes prepared from polymers containing triazole cryptether side chains exhibit excellent alkaline stability and high conductivity, and have promising application prospects in the field of AEM.

[0179] The present invention has been described in detail above with reference to specific embodiments and / or exemplary examples, as well as the accompanying drawings. However, these descriptions should not be construed as limiting the present invention. Those skilled in the art will understand that various equivalent substitutions, modifications, or improvements can be made to the technical solutions and embodiments of the present invention without departing from the spirit and scope of the invention, and all such modifications and improvements fall within the scope of the present invention. The scope of protection of the present invention is defined by the appended claims.

Claims

1. A polymer containing a triazole cryptether branch, wherein the triazole cryptether branch is selected from 1,2,3-triazole cryptether branches, and the structure of the triazole cryptether branch is as follows: ， The polymer was prepared by a click reaction of a [2.2.2]-catechol ether compound containing an alkyne substituent with an azide polymer. The [2.2.2]-cavitary ether containing an alkynyl substituent is selected from compounds having the following structure: in, y is 1; The azide polymer is selected from polymers having the following structural units: , The azide polymer is also selected from copolymers containing the following structural units: and ; Where x is between 1 and 7, and x is an integer.

2. The polymer according to claim 1, characterized in that, x is between 1 and 5.

3. The polymer according to claim 2, characterized in that, x is between 1 and 3.

4. A method for preparing a polymer containing a triazole cryptether branch according to any one of claims 1 to 3, characterized in that, The method prepares a polymer containing triazole cavitary ether branches by clicking reaction of a [2.2.2]-cavitary ether compound containing an alkynyl substituent with an azide polymer; The click reaction is a cycloaddition reaction of an azide group and an alkynyl group carried out under a copper catalyst, wherein the copper catalyst is selected from monovalent copper salts or copper complexes.

5. The method according to claim 4, characterized in that, The copper catalyst is selected from cuprous iodide and / or cuprous chloride.

6. The method according to claim 5, characterized in that, The click reaction also includes a ligand compound selected from organic amines.

7. The method according to claim 6, characterized in that, The ligand compound is selected from triethylamine and / or N , N -Diisopropylethylamine.

8. The method according to claim 4, characterized in that, The click reaction also includes a reducing agent, selected from one or more amino acids and ascorbic acid salts.

9. The method according to claim 8, characterized in that, The reducing agent is ascorbate.

10. The method according to claim 4, characterized in that, The [2.2.2]-cavitary ether compounds containing alkynyl substituents are prepared by a method comprising the following steps: Step 1: React an alkynyl diol with a 2-haloethanol ether protected by an uranium group to remove the uranium protection and obtain intermediate product I. Step 2: Add p-toluenesulfonyl chloride to a solution containing intermediate product I and react to obtain intermediate product II; Step 3: React intermediate product II with diaza-18-crown ether-6 to prepare [2.2.2]-cavitary ether compounds containing alkynyl substituents.

11. The method according to claim 10, characterized in that, In step 1, the alkynyl-containing diol is selected from diol compounds having the following structures: ； The 2-haloethanol ether protected by uranium is selected from 2-(2-bromoethoxy)tetrahydropyran and / or 2-[(2-bromoethoxy)methyl]tetrahydrofuran; The intermediate product I is selected from compounds having the following structures: 。 12. The method according to claim 11, characterized in that, In step 1, the alkynyl-containing diol is ; The 2-haloethanol ether protected by uranium is 2-(2-bromoethoxy)tetrahydropyran; The intermediate product I is .

13. The method according to claim 10, characterized in that, In step 2, the intermediate product II is selected from compounds having the following structures: Where Ts is .

14. Use of a polymer containing a triazole cryptether branch according to any one of claims 1 to 3, characterized in that, It is used to prepare anion exchange membranes in anion fuel cells.

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