Anion exchange resin containing fluorinated alkyl side chain and preparation method of membrane of anion exchange resin

Abstract

The invention belongs to the technical field of anion exchange resin, and particularly relates to fluorinated alkyl side chain anion exchange resin and a preparation method of a membrane of the fluorinated alkyl side chain anion exchange resin. The anion exchange polymer poly (aryl-alkylene) comprises a side chain with a polyfluorine structure, and the hydrophobicity of a fluorine element on the side chain reduces the water absorption of a skeleton chain. And the stability of a membrane framework is guaranteed by improving the anti-swelling performance. When the length of a fluorocarbon chain on a side chain is increased, the phase separation degree is higher, and the ionic conductivity is higher. The main chain of the anion exchange polymer poly (aryl-alkylene) does not contain heteroatoms such as sulfur, ether and oxygen, so that unstable electron-rich sites generated on aryl by the electron donating effect of the heteroatoms are avoided, and hydroxyl radicals are not easy to attack the poly (aryl-alkylene) polymer. In addition, the fluorine-containing functional group can reduce the density of benzene electron cloud, effectively prevent attack of free radicals and increase the stability of a main chain.

Description

Technical Field

[0001] The invention belongs to the technical field of anion exchange resins, and particularly relates to an anion exchange resin containing a fluorinated alkyl side chain and a preparation method of a membrane thereof. Background Art

[0002] Low-temperature water electrolysis technology provides a clean, efficient and sustainable way to produce high-purity hydrogen. Low-temperature water electrolyzers are commonly used in industry to produce hydrogen. There are three main types of low-temperature water electrolyzers: conventional alkaline electrolyzers, proton exchange membrane (PEM) electrolyzers and anion exchange membrane (AEM) electrolyzers. Among them, compared with the other two types of electrolyzers, AEM electrolyzers have the characteristics of being able to use low or non-platinum-based metal (PGM) electrocatalysts and produce pressurized hydrogen in an alkaline environment. It is the focus of current research, and hydroxide exchange membrane water electrolysis (AEMWE) is also known as the most ideal method for hydrogen production. The AEM electrolyzer consists of an anion exchange membrane and a catalytic electrode, and generally uses pure water or a low-concentration alkaline solution as an electrolyte. Among them, the anion exchange membrane (AEM) is the core part of the AEMWE water electrolysis system. Its function is to conduct OH- while blocking the direct transfer of gases and other ions between the electrodes. However, the OH in the AEM - The conduction efficiency is much lower than that of H + The conduction efficiency in its acidic counterpart is low, which results in significant dissipation losses in energy conversion applications.

[0003] Ionic conductivity is determined by two factors: ion mobility and ion exchange capacity (IEC). - To improve electrical conductivity, the conventional approach is to increase the IEC value. However, high IEC is often accompanied by excessive water absorption and swelling, which can lead to significant swelling and deformation of the AEM membrane, thereby reducing device durability. CN118344634A discloses a fluoroformaldehyde-containing piperidine-type anion exchange membrane and a preparation method thereof. The membrane material is obtained by synthesizing a fluoroformaldehyde-containing piperidine-type trimonomer polymer in varying proportions and then directly quaternizing the polymer using the piperidone of the polymer as a grafting site. This method improves conductivity while also resulting in very high water absorption and swelling. The water absorption at 80°C is as high as 76.14-130.06%, and the swelling is as high as 18.3-40.0%.

[0004] Another method for increasing OH- conductivity is to promote OH- mobility in AEMs. A common approach is to introduce hydrophobic chains to enhance hydrophilic / hydrophobic microphase separation, driving ion clusters on the AEM to form larger ion channels. This approach can effectively address the problems of excessive water absorption and swelling. CN112552488A discloses an ionomer containing alkali-resistant cationic groups and fluorocarbon side chains, as well as its preparation method and application. In this preparation method, a precursor polymer containing fluorocarbon side chains and piperidine moieties is prepared by condensation polymerization or condensation copolymerization of an aromatic compound with an N-substituted piperidone, a methyl perfluoroalkyl ketone, a trifluoroalkyl ketone, or a trifluoroaryl ketone under strong acid catalysis. Water absorption remains as high as 58% at 80°C and 47% at room temperature, while dimensional stability remains poor. Furthermore, its resistance to alkaline hydrolysis in a 2M NaOH solution at 80°C is only approximately 300 hours. In addition, the methyl perfluoroalkyl ketone used in the invention has β-H, which easily forms an enol form during the reaction and competes with the aromatic compound, resulting in the generation of by-products and limiting the degree of polymerization of the polymer.

[0005] The performance of AEM, including poor thermal and chemical stability and limited anion conductivity, restricts the lifespan and electrolytic performance of AEM electrolyzers and is currently the primary limiting factor in the development of AEMWE (Aqueous Electrolyzer) water electrolysis technology. The search for high-conductivity polymers with excellent chemical and alkaline stability remains a key research priority.

[0006] To this end, the present invention introduces a polyfluorinated structure into the side chain to achieve better phase separation of the membrane, thereby increasing the conductivity of OH- while reducing the water absorption and swelling rate of the membrane. Summary of the Invention

[0007] The purpose of the present invention is to solve the existing problems and provide a method for preparing an anion exchange resin with a fluorinated alkyl side chain and a membrane thereof.

[0008] The present invention is achieved through the following technical solutions:

[0009] A method for preparing an anion exchange resin containing a fluorinated alkyl side chain and a membrane thereof comprises the following steps:

[0010] S1: dissolving an aromatic structure monomer (0.1 mol) of formula 2A, a perfluorocarbon chain structure monomer of formula 1A or formula 1B, and an optional cationic group monomer (0.1 mol) of formula 3A or 3B or 3C or 3D in 60 mL of an organic solvent, cooling the temperature to 0°C with an ice bath, adding a catalyst dropwise, and polymerizing at 0°C for 2 to 12 days. After the reaction is completed, a polar solvent is added to the reaction solution to quench the reaction, and the polymer is dissolved under stirring at 100°C. The dissolved mixed solution is poured into a precipitation solvent, precipitated, filtered under reduced pressure, washed with deionized water 2 to 3 times, and then vacuum dried at 80°C for 12 hours to obtain a dry white solid;

[0011] S2: The dry white solid prepared above is dissolved in a polar solvent, and then alkylated with a quaternary amine or a nitrogen-containing heterocycle and an alkylating agent at room temperature for more than 12 hours. The light yellow solid is precipitated and filtered with a solvent, and then washed with distilled water and dried.

[0012] Furthermore, the structures of Formula 1A, Formula 1B, Formula 2A, Formula 3A, Formula 3B, Formula 3C, and Formula 3D in step S1 are respectively as follows:

[0013]

[0014] Furthermore, each of the R1s is independently selected from one or more of the following structures:

[0015]

[0016] k represents an integer between 1 and 10;

[0017] Said R2 is selected from hydrogen or methyl;

[0018] Said R3, R4, R5 and R6 are each independently any one of hydrogen, halide, alkyl, alkenyl, alkynyl, and aryl, and said alkyl, alkenyl, alkynyl or aryl is optionally substituted with halide;

[0019] R8, R9, R 10 、R 11 and R 12 are each independently an alkyl group;

[0020] In Formula 2A, the dotted portion is present or absent. When the dotted portion is absent, R7 is absent. When the dotted portion is present, R7 is an alkyl group, an alkenyl group, or an alkynyl group, and the alkyl group, the alkenyl group, or the alkynyl group is optionally substituted with a halide.

[0021] The R 20 、R 30 、R 40 、R 50 、R 60 、R 70 、R 80 and R 90 are each independently any one of hydrogen, halide, alkyl, alkenyl, alkynyl, and aryl, and the alkyl, alkenyl, alkynyl, or aryl is optionally substituted with halide, and wherein R 30 and R 60 an optionally attached halide or alkyl-substituted five- or six-membered ring;

[0022] The R 13 is oxygen, sulfur, nitrogen, alkyl, alkenyl, alkynyl, or a substituent having the following structure:

[0023]

[0024] R 110 、R 120 、R 130 and R 140 Each is independently any one of hydrogen, halide, alkyl, alkenyl, alkynyl, and aryl, and the alkyl, alkenyl, alkynyl, or aryl is optionally substituted with halide;

[0025] R 100 is a cation exchange group;

[0026] n represents an integer between 0 and 5;

[0027] m represents an integer between 0 and 10;

[0028] p represents an integer between 0 and 10;

[0029] The cation exchange group is a quaternary ammonium or a nitrogen-containing heterocycle:

[0030]

[0031] in:

[0032] R 17 are each independently an alkyl group;

[0033] R 14 、R 15 、R 16 、R 18 and R 19 Each is independently any one of alkyl, alkenyl, aryl, and alkynyl;

[0034] a is 0, 1, 2, 3, 4, 5, or 6;

[0035] R' is a nitrogen-containing heterocyclic ring;

[0036] The nitrogen-containing heterocycle comprises optionally substituted pyrrole, pyrroline, pyrazole, pyrazoline, imidazole, imidazoline, triazole, pyridine, triazine, pyrazine, pyridazine, pyrimidine, azepine, quinoline, piperidine, pyrrolidine, pyrazolidine, imidazolidine, wherein each substituent is independently alkyl, alkenyl, alkynyl or aryl;

[0037] Nitrogen-containing heterocyclic groups include imidazolium groups having (Formula 4):

[0038]

[0039] Where: R 150 、R 160 、R 170 and R 180Each is independently any one of hydrogen, halide, alkyl, alkenyl, alkynyl, and aryl, and the alkyl, alkenyl, alkynyl, or aryl is optionally substituted with halide;

[0040] X - Anion: Br - , I - 、Cl - OH - 、HCO3 - .

[0041] Furthermore, the organic solvent described in step S1 is one or a combination of, but not limited to, dichloromethane, dichloroethane, trifluoroacetic acid, trifluoromethanesulfonic acid, chloroform, 1,1,2,2-tetrachloroethane, and dimethylacetamide.

[0042] Furthermore, the catalyst in step S1 is trifluoromethanesulfonic acid, pentafluoroethanesulfonic acid, heptafluoro-1-propanesulfonic acid, trifluoroacetic acid, perfluoropropionic acid, heptafluorobutyric acid or a combination thereof.

[0043] Furthermore, the polar solvent in step S1 and step S2 is the same, which is one of NMP, DMF, DMSO, and DMAc.

[0044] Furthermore, the precipitation solvent in step S1 includes but is not limited to water, methanol, ethanol, propanol, isopropanol, butanol, isobutanol, pentanol, tetrahydrofuran or a combination thereof.

[0045] Furthermore, the basic structure of the quaternary amine or nitrogen-containing heterocycle described in step S2 is as follows:

[0046]

[0047] in:

[0048] R 17 are each independently an alkylene group;

[0049] R 14 、R 15 、R 16 、R 18 and R 19 are each independently alkyl, alkenyl, aryl or alkynyl;

[0050] a is 0, 1, 2, 3, 4, 5, or 6;

[0051] R' is a nitrogen-containing heterocyclic ring.

[0052] The nitrogen-containing heterocycle comprises optionally substituted pyrrole, pyrroline, pyrazole, pyrazoline, imidazole, imidazoline, triazole, pyridine, triazine, pyrazine, pyridazine, pyrimidine, azepine, quinoline, piperidine, pyrrolidine, pyrazolidine, imidazolidine, wherein each substituent is independently alkyl, alkenyl, alkynyl or aryl;

[0053] The nitrogen-containing heterocyclic group may include an imidazolium having (Formula 4).

[0054]

[0055] Where: R 150 、R 160 、R 170 and R 180 Each is independently hydrogen, halide, alkyl, alkenyl, alkynyl or aryl, and the alkyl, alkenyl, alkynyl or aryl is optionally substituted with halide.

[0056] X - Anion: Br - , I - 、Cl - OH - 、HCO3 -

[0057] Furthermore, the solvent in step S2 includes but is not limited to ethyl acetate, propyl acetate, n-butyl acetate, isobutyl acetate or a combination thereof.

[0058] Furthermore, the alkylating agent described in step S2 includes but is not limited to methyl iodide, ethyl iodide, 1-iodopropane, 1-iodobutane, 1-iodopentane, 1-iodohexane, 1,10-dibromodecane, methyl bromide, ethyl bromide, 1-bromopropane, 1-bromobutane, 1-bromopentane, 1-bromohexane, methyl chloride, ethyl chloride, 1-chloropropane, 1-chlorobutane, 1-chloropentane, 1-chlorohexane, 1,3- dibromopropane, 1,4-dibromobutane, 1,5-dibromopentane, 1,6-dibromohexane, 1,7-dibromoheptane, 1,3-diiodopropane, 1,4-diiodobutane, 1,5-diiodopentane, 1,6-diiodohexane, 1,7-diiodoheptane, methyl trifluoromethanesulfonate, methyl methanesulfonate, methyl fluorosulfonate, 1,2-dimethylhydrazine, trimethyl phosphate, dimethyl sulfate, or a combination thereof.

[0059] An anion exchange membrane is made of an anion exchange resin containing a fluorinated alkyl side chain. The anion exchange membrane includes a uniform anion exchange membrane and an enhanced anion exchange membrane.

[0060] Furthermore, the preparation method of the uniform anion exchange membrane is as follows: the light yellow solid obtained above is vacuum dried at 80°C for 24 hours, dissolved in a polar solvent (one or more of NMP, DMF, DMSO, DMAc, etc.) and centrifuged, cast on a substrate, dried at 60-100°C for 5-24 hours to form a membrane, and then vacuum dried at 80-150°C for 5-24 hours. The thickness of the membrane is between 10 and 100 μm.

[0061] More preferably, the thickness of the film is 30 to 50 μm.

[0062] Furthermore, the substrate includes but is not limited to stainless steel plate, glass, PET plate, PP plate, PEN, etc.

[0063] Furthermore, the enhanced anion exchange membrane can be prepared by methods including but not limited to the following: wetting a porous substrate in a liquid to form a wetted substrate; dissolving the anion exchange resin polymer containing fluorinated alkyl side chains obtained above in a solvent to form a uniform solution; applying the solution to the wetted substrate to form the enhanced membrane; and drying the enhanced membrane.

[0064] Further, the reinforced membrane can be impregnated with polymer multiple times by any known membrane forming technique, such as casting, spraying, dipping or knife coating onto the wetted substrate, and if necessary, by rewetting the reinforced membrane and repeating the dissolving, casting and drying steps.

[0065] Furthermore, the porous substrate used in the preparation of the enhanced anion membrane includes but is not limited to PPS, PEK, PET, porous polytetrafluoroethylene, porous polyvinylidene fluoride, steel belt, polypropylene, polyethylene, glass fiber cloth, etc.

[0066] Furthermore, the liquid used to wet the porous substrate may be a low-boiling point solvent, such as lower alcohol or water.

[0067] More preferably, the liquid is anhydrous ethanol.

[0068] Furthermore, the porous substrate may have a thickness of 1 μm to 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95 or 100 μm.

[0069] More preferably, the thickness of the porous substrate is 5 to 30 μm, or 7 to 20 μm.

[0070] In Formula 1A, a perfluoroalkyl aldehyde without β-H is used as a substrate to introduce a perfluorocarbon structure into the side chain, thereby avoiding the enol interconversion of the substrate and the competitive reaction with the aromatic compound to produce by-products during the polymerization process, thereby increasing the molecular weight of the polymer to a certain extent.

[0071] Compared with the prior art, the present invention has the following advantages:

[0072] 1. The anion exchange polymer poly(aryl-alkylene) of the present invention contains a polyfluorinated side chain. The hydrophobicity of the fluorine element on the side chain reduces the water absorption of the backbone chain. This improved anti-swelling performance ensures the stability of the membrane backbone. Increasing the length of the carbon-fluorine chain on the side chain enhances phase separation and ionic conductivity.

[0073] 2. The anion exchange polymer poly(aryl-alkylene) of the present invention does not contain heteroatoms such as sulfur, ether, or oxygen on its backbone. This prevents the electron-donating effect of these heteroatoms from creating unstable electron-rich sites on the aromatic groups, making it difficult for hydroxyl radicals to attack the poly(aryl-alkylene) polymer. Furthermore, the fluorinated functional groups in the present invention can reduce the electron cloud density of benzene, effectively preventing free radical attack and increasing backbone stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0074] Figure 1 The water absorption, electrical conductivity, and IEC test results of Examples 1 to 5 and Comparative Example 1 are shown;

[0075] Figure 2 The anti-aging test results of Example 1, Example 2 and Comparative Example 1 are shown;

[0076] Figure 3 For Example 1 1 H NMR spectra;

[0077] Figure 4 The molecular weight data (GPC) of Example 4. DETAILED DESCRIPTION

[0078] In order to further explain the present invention, it is described below with reference to the following specific embodiments.

[0079] AEMs formed from polymers with various pendant cationic groups and cation-conducting channels have been reported, with (biphenyl-subunit) polymers being representative. These polymers offer improved chemical stability, electrical conductivity, water absorption, mechanical properties, and other attributes relevant to AEM performance. The present invention synthesizes a polymer containing perfluorocarbon alkane side chains and a backbone free of heteroatoms such as sulfur, ether, and oxygen. Compared to conventional AEMs, AEMs formed from these structural units exhibit both increased hydrophobicity and good phase separation, while also displaying the superior alkaline stability of (biphenyl-subunit) polymers.

[0080] The polymer includes perfluorocarbon chain structural units of formula 1A and formula 1B, aromatic structural units of formula 2A, and optional cationic group structural units of formula 3A as shown in the figure below.

[0081] 1. Perfluorocarbon chain structural units of formula 1A and formula 1B

[0082]

[0083] The R1 are each independently selected from one or more of the following structures:

[0084]

[0085] k represents an integer between 1 and 10, such as 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10.

[0086] Said R2 is selected from hydrogen or methyl;

[0087] Said R3, R4, R5 and R6 are each independently hydrogen, halide, alkyl, alkenyl, alkynyl or aryl, and said alkyl, alkenyl, alkynyl or aryl is optionally substituted with halide;

[0088] (i) As an example, the monomer of formula 1A includes, but is not limited to, trifluoroacetaldehyde hydrate, pentafluoropropionaldehyde hydrate, heptafluorobutyraldehyde hydrate, nonafluoropentanal hydrate, perfluorohexanal hydrate, etc.; or a hydrate containing a heteroatom as shown in the following figure;

[0089]

[0090] (ii) As an example, the monomer of formula 1B includes but is not limited to the compound shown in the following figure;

[0091]

[0092] As an example, another method for synthesizing a monomer of formula 1B is provided:

[0093] Add dichloromethane (300 mL) to a flask, followed by 0.22 mol of aluminum chloride, and stir at below 5°C. Place pentafluoropropionic anhydride (0.13 mol) in the flask and stir for 15 minutes. Add a diluted solution of benzaldehyde (0.1 mol in 50 mL of dichloromethane) dropwise. After the addition is complete, react at 0°C for 16 hours. When the reaction is complete, filter the filtrate, pour it into ice water, extract with ether, and evaporate. The product is recrystallized from acetonitrile to obtain a white solid (15.68 g) with a yield of 70%.

[0094]

[0095] In other cases, similar methods can be used to synthesize the monomer of formula 1B.

[0096] 2. Aromatic structural units

[0097]

[0098] n represents an integer between 0 and 5, such as 0, 1, 2, 3, 4 and 5.

[0099] In Formula 2A, the dotted line portion may be present or absent. When the dotted line portion is absent, R7 is absent. When the dotted line portion is present, R7 is an alkyl group, an alkenyl group, or an alkynyl group, and the alkyl group, the alkenyl group, or the alkynyl group is optionally substituted with a halide.

[0100] The R 20 、R 30 、R 40 、R 50 、R 60 、R 70 、R 80 and R 90 are each independently hydrogen, halide, alkyl, alkenyl, alkynyl or aryl, and said alkyl, alkenyl, alkynyl or aryl is optionally substituted with halide, and wherein R 30 and R 60 an optionally attached halide or alkyl-substituted five- or six-membered ring;

[0101] As an example, the monomer of formula 2A includes but is not limited to the compound shown in the following figure;

[0102]

[0103] As an example, a method for synthesizing a monomer of formula (2A) (named QBPAF-C6) is provided:

[0104] 1,6-diiododecafluorohexane (0.036 mol, 20 g), tetrahydrofuran (90 g), NMP (90 g) and copper powder (4.6 g) were added to a 500 mL four-necked round-bottom flask and stirred for 2 h under nitrogen protection. 4-iodobiphenyl (0.072 mol, 20.2 g) was then added to the mixture. The temperature was raised to 125°C and the reaction was continued for 48 h. Water was added dropwise to quench the reaction, and the mixture was extracted with ethyl acetate. The organic phase was dried over anhydrous magnesium sulfate and the solvent was removed by rotary evaporation. 19.4 g of pure polymer monomer was obtained by column chromatography with a yield of 89%. The synthesis equation is as follows:

[0105]

[0106] 3. Cationic group structural unit

[0107]

[0108] R8, R9, R 10 、R 11 and R 12 are each independently an alkyl group;

[0109] The R13 is oxygen, sulfur, nitrogen, alkyl, alkenyl, alkynyl, etc., or a substituent having the following structure:

[0110]

[0111] R 110 、R 120 、R 130 and R 140 Each is independently hydrogen, halide, alkyl, alkenyl, alkynyl or aryl, and the alkyl, alkenyl, alkynyl or aryl is optionally substituted with halide.

[0112] R 100 A cation exchange group.

[0113] m represents an integer between 0 and 10, such as 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10.

[0114] The monomers of formula 3A and 3B include piperidone monomers or salts or hydrates thereof;

[0115] The salt of the piperidinone may comprise a hydrochloride, hydrofluoride, hydrobromide, hydroiodide, trifluoroacetate, acetate, triflate, methanesulfonate, sulfate, nitrate, tetrafluoroborate, hexafluorophosphate, formate, benzenesulfonate, toluate, perchlorate, or benzoate, or any hydrate of the salt, or any combination thereof. For example, the salt of the piperidone monomer can include 4-piperidone hydrofluoride, 4-piperidone hydrochloride, 4-piperidone hydrobromide, 4-piperidone hydroiodide, 4-piperidone trifluoroacetate, 4-piperidone tetrafluoroborate, 4-piperidone hexafluorophosphate, 4-piperidone acetate, 4-piperidone trifluoromethanesulfonate, 4-piperidone methanesulfonate, 4-piperidone formate, 4-piperidone benzenesulfonate, 4-piperidone toluate, 4-piperidone sulfate, 4-piperidone nitrate, 4-piperidone perchlorate, 4-piperidone benzoate, N-methyl-4-piperidone hydrofluoride, N-methyl-4-piperidone hydrochloride, N-methyl-4-piperidone hydrobromide, salt, N-methyl-4-piperidone hydroiodide, N-methyl-4-piperidone trifluoroacetate, N-methyl-4-piperidone tetrafluoroborate, N-methyl-4-piperidone hexafluorophosphate, N-methyl-4-piperidone acetate, N-methyl-4-piperidone trifluoromethanesulfonate, N-methyl-4-piperidone methanesulfonate, N-methyl-4-piperidone formate, N-methyl-4-piperidone benzenesulfonate, N-methyl-4-piperidone toluate, N-methyl-4-piperidone sulfate, N-methyl-4-piperidone nitrate, N-methyl-4-piperidone perchlorate, N-methyl-4-piperidone benzoate, or any hydrate of the salt, or any combination thereof.

[0116] For example, a 3-oxo-6-azaspiro[5,5]undecane salt monomer having the formula:

[0117]

[0118] As an example, the synthesis method of nitrogen spiro salt:

[0119] A mixture of KCO (23.0 g, 166.6 mmol), 1,5-diiodopentane (53.83 g, 166.6 mmol), and 4-piperidone hydrobromide (10 g, 55.5 mmol) was stirred in 500 mL of acetone for 24 h. The solvent was then removed by rotary evaporation, and the crude product was subsequently diluted with 300 mL of acetonitrile and heated at 70°C for 15 h to obtain a solid iodinated 3-oxo-6-azaspiro[5,5]undecane salt monomer. The product was filtered and dried under vacuum.

[0120]

[0121] As another example, the synthesis method of azaspiro salt:

[0122] A mixture of KCO (23.0 g, 166.6 mmol), 1,4-diiodobutane (51.63 g, 166.6 mmol) and 4-piperidone hydrobromide (10 g, 55.5 mmol) was stirred in 500 mL of acetone for 24 h. The solvent was then removed by rotary evaporation, and the crude product was then diluted with 300 mL of acetonitrile and heated at 70 ° C for 15 h to obtain a solid nitrogen iodide spiro salt monomer. The product was filtered and dried in vacuo.

[0123]

[0124] X - Anion: Br - , I - 、Cl - OH - 、HCO3 - wait.

[0125] In other cases, similar or other methods can be used to synthesize monomers having the structural formula (3B).

[0126] As an example, monomers of formula 3C include but are not limited to the compounds shown below;

[0127]

[0128] As an example, a synthesis method of a monomer having a structure of formula (3C) is provided:

[0129] To synthesize the ketone monomer 5-bromo-1,1,1-trifluoromethyl-2-one, 4-bromobutyric acid (167 g, 1 mol, 1 eq) was dissolved in toluene (400 ml) in a 5000 ml three-necked flask. Trifluoroacetic anhydride (778.4 ml, 5.6 mol, 5.58 eq) was slowly added under stirring in an ice bath. After cooling to 0°C, pyridine (650 mL, 8 mol, 8 eq) was added dropwise. After the addition was complete, the temperature was raised to 50°C. The mixture was reacted under nitrogen for 48 h. Then, the temperature was lowered to 0°C, 1430 ml of deionized water was added dropwise, and the temperature was raised to 45°C for reaction for 2 h.

[0130] After the reaction, the layers were allowed to stand and the organic layer was extracted with ethyl acetate (4 x 1250 mL). The organic phase was washed sequentially with deionized water, saturated sodium carbonate, and saturated sodium chloride solution, and then dried over anhydrous sodium sulfate. The solvent was then evaporated, and the product, 5-bromo-1,1,1-trifluoromethyl-2-one (65.4 g, approximately 30% yield), was isolated by column chromatography to give light brown crystalline product. The synthesis equation is shown in the figure below.

[0131]

[0132] As another example, another method for synthesizing a monomer of formula (3C) is provided:

[0133] Bromoalkylated perfluoropropiophenone monomers are obtained via Friedel-Craft acylation. Add dichloromethane (300 mL) to a flask, followed by 0.22 mol of aluminum chloride, and stir at below 5°C. Add pentafluoropropionic anhydride (0.13 mol) to the flask and stir for 15 minutes. Add a diluted solution of 1-bromo-3-phenylpropane (0.1 mol in 50 mL of dichloromethane) dropwise. After the addition is complete, react at 0°C for 16 hours. Pour the reaction mixture into ice water and stir for 10 minutes. Separate the layers, extract the aqueous phase twice with DCM, and combine the organic phases; wash the organic phases three times with saturated sodium bicarbonate solution and three times with deionized water. Dry over anhydrous sodium sulfate. Dry under reduced pressure at 40°C to obtain a crude solid. Dissolve the crude solid in a 2:8 DCM / cyclohexane solution and allow to crystallize at 0°C. Filter the mother liquor and spin dry. Repeat the above recrystallization to obtain the fine product, and obtain 13.42g of product with a yield of 39%.

[0134]

[0135] As an example, monomers of formula 3D include, but are not limited to, the compounds shown below;

[0136]

[0137] As an example, a synthesis method of a monomer having a structure of formula (3D) is provided:

[0138] S1: Toluene (4.7 mol) and butanol (0.07 mol) were mixed and stirred, potassium tert-butoxide (0.35 mol) was added, and the temperature was raised to 105°C. A mixed solution of 1-ethoxycarbonylmethyl-4-piperidinic acid ethyl ester (0.21 mol) and toluene (0.9 mol) was slowly added dropwise under reflux. After the addition was completed, the reflux reaction was continued for 3 hours. The obtained reaction mixture was acidified with hydrochloric acid solution, the aqueous phase was separated, and the organic phase was extracted with dilute hydrochloric acid (10%, 0.55 mol). The aqueous phases were combined to obtain a ketoester hydrochloride solution.

[0139] S2: Activated carbon (0.83 mol) was added to the ketoester hydrochloride solution obtained in S1, and then the temperature was raised to 60°C and refluxed for 7 h. After the reaction, the temperature was lowered to 30°C, and the activated carbon was removed by filtration. Sodium carbonate (1.8 mol) was slowly added to the filtrate in batches, and the pH value was adjusted to 8. After filtration, the mixture was extracted three times with DCM, and the organic phases were separated and combined. The crude solid was dried under reduced pressure at 40°C, and 0.178 mol of 3-quinuclidinone was obtained after drying under reduced pressure. The yield was 85.6% and the purity was 99.12%.

[0140]

[0141] 4. The quaternary ammonium or nitrogen-containing heterocycle is:

[0142]

[0143] in:

[0144] R 17 are each independently an alkyl group;

[0145] R 14 、R 15 、R 16 、R 18 and R 19 are each independently alkyl, alkenyl, aryl or alkynyl;

[0146] a is 0, 1, 2, 3, 4, 5, or 6;

[0147] R' is a nitrogen-containing heterocyclic ring.

[0148] The nitrogen-containing heterocycle comprises optionally substituted pyrrole, pyrroline, pyrazole, pyrazoline, imidazole, imidazoline, triazole, pyridine, triazine, pyrazine, pyridazine, pyrimidine, azepine, quinoline, piperidine, pyrrolidine, pyrazolidine, imidazolidine, wherein each substituent is independently alkyl, alkenyl, alkynyl or aryl;

[0149] The nitrogen-containing heterocyclic group may include an imidazolium having (Formula 4).

[0150]

[0151] Where: R 150 、R 160 、R 170 and R 180 Each is independently hydrogen, halide, alkyl, alkenyl, alkynyl or aryl, and the alkyl, alkenyl, alkynyl or aryl is optionally substituted with halide.

[0152] X - Anion: Br - , I - 、Cl - OH - 、HCO3 - ;

[0153] As an example: a is 0, R 14 、R 15 、R 16 is methyl, R 17 It is hexamethylene and named (MQN).

[0154] Synthesis of MQN-Br. A mixture of THF (100 mL) and trimethylamine ethanol solution (1 eq) was added dropwise to a solution of 1,6-dibromohexane (0.15 mol, 5 eq) in THF (200 mL). After the addition, the mixture was stirred for 24 h. A white solid slowly formed. The white precipitate was filtered and washed with cold THF. After vacuum drying, MQN-Br was obtained as a white or light yellow powder (90% yield).

[0155]

[0156] As another example: a is 1, R 14 、R 15 、R 16 is methyl, R 17 It is hexamethylene and named (PMDA).

[0157] Synthesis of pentamethyldiammonium side chain (PMDA). A THF solution of MeI (1 eq) was added dropwise to N,N,N',N'-tetramethyl-1,6-hexanediamine (2 eq) and THF at 0°C under mechanical stirring over 1 hour. The reaction was then continued at this temperature for 24 hours. The resulting slurry with a white precipitate was filtered and washed with cold THF. The product was vacuum dried and collected, yielding 90% yield.

[0158]

[0159] The present invention provides a method for preparing an ion exchange polymer membrane according to the present invention. The method comprises: reacting an optional cationic group monomer, a perfluorocarbon chain monomer, and an aromatic monomer in the presence of an organic solvent and a polymerization catalyst to form a polymer; subjecting the polymer to an alkylation reaction to obtain a target ion polymer; dissolving the target ion polymer in a polar solvent (such as NMP / DMSO / DMF) to form a uniform solution, casting the polymer solution on stainless steel to form a polymer membrane; and subjecting the polymer membrane to cation exchange to obtain an anion exchange membrane.

[0160] For example, optional cationic group monomers, such as N-methyl-4-piperidone or 4-piperidone, perfluorocarbon chain monomers, such as perfluoropropionaldehyde hydrate and aromatic monomers, can be dissolved in an organic solvent (e.g., DCM) with an overhead stirrer. A polymerization catalyst (e.g., trifluoromethanesulfonic acid) is then added dropwise at 0°C, and the reaction is continued at this reaction temperature for about 1 to 72 hours. The resulting solution is slowly poured into an ethanol aqueous solution. The solid obtained is filtered, washed with water and immersed in 1M sodium hydroxide at room temperature for about 1 to 48 hours. Finally, the product is filtered, washed with water and completely dried under vacuum to form a first intermediate polymer. The first intermediate polymer is subjected to an alkylation reaction to obtain the target polymer.

[0161] Example 1

[0162] Poly(aryl-piperidinium) was prepared from N-methyl-4-piperidone, pentafluoropropionaldehyde hydrate, and p-terphenyl (designated FPAP-1-x, where x is the molar ratio of N-methyl-4-piperidone to p-terphenyl and ranges from 1 to 100). FPAP-1-x was prepared by the following three main steps:

[0163] (1) Synthesis of poly(aryl-piperidine) polymer. In a 50 mL three-necked flask equipped with a magnetic stirrer, N-methyl-4-piperidone (1.054 ml, 8.5 mmol), pentafluoropropionaldehyde hydrate (0.2 g, 1.5 mmol) and p-terphenyl (2.3 g, 10 mmol) were dissolved in dichloromethane (10 mL) and trifluoroacetic acid (0.77 mL) and trifluoromethanesulfonic acid (TFSA) (7.96 mL) were added dropwise at 0°C over 30 min. Thereafter, the reaction was continued at this temperature for 4 to 48 h. The resulting viscous dark green solution was slowly poured into an ethanol-water solution. The white fibrous solid was filtered, washed with water and immersed in 1 M sodium hydroxide at room temperature for 12 h. Finally, the white fibrous product was filtered, washed with water and dried under vacuum at 80°C for 12 h. The yield of the polymer was 97%.

[0164] (2) Synthesis of alkylated polymer (FPAP-1-85). In a 50 mL single-necked flask equipped with magnetic stirring, the piperidine-functionalized polymer (1.0 g) was dissolved in 1-methyl-2-pyrrolidone (20 mL). Iodomethane (1 mL) was quickly added. The solution was stirred at room temperature for 12 h. The resulting viscous yellow solution was added dropwise to diethyl ether. The yellow solid was filtered, washed with diethyl ether and completely dried under vacuum at 60°C. The yield of polymer FPAP-1-85 was almost 100%.

[0165] (3) FPAP-1-85 forged membrane and hydroxide ion exchange. FPAP-1-85 polymer (1.0 g) was dissolved in NMP (20 mL), cast on a glass plate or stainless steel plate, dried at 60-100°C for 5-24 h to form a membrane, and then vacuum dried at 80-150°C for 5-24 h. The membrane thickness was between 10 and 100 μm. The membrane was peeled off from the glass plate while in contact with deionized water. The membrane was subjected to hydroxide ion exchange in 1 M sodium hydroxide solution at 80°C to obtain an anion exchange membrane in the hydroxide form. Other FPAP-1-x membranes were prepared by using different molar ratios of N-methyl-4-piperidone and p-terphenyl.

[0166] The synthesis formula is as follows:

[0167]

[0168] This embodiment 1 H NMR spectrum Figure 3 shown

[0169] Example 2

[0170] Poly(aryl-alkylene) is prepared from 5-bromo-1,1,1-trifluoromethyl-2-one, pentafluoropropionaldehyde hydrate, and p-terphenyl (designated FPAP-2-x, where x is the molar ratio of 5-bromo-1,1,1-trifluoromethyl-2-one to p-terphenyl, ranging from 1 to 100). FPAP-2-x is prepared by the following three main steps:

[0171] (1) Synthesis of poly(aryl-alkylene) polymers. In a 50 mL three-necked flask equipped with a magnetic stirrer, 5-bromo-1,1,1-trifluoromethyl-2-one (1.85 g, 8.5 mmol), pentafluoropropionaldehyde hydrate (0.2 g, 1.5 mmol) and p-terphenyl (2.3 g, 10 mmol) were dissolved in dichloromethane (10 mL) and trifluoroacetic acid (0.77 mL) and trifluoromethanesulfonic acid (TFSA) (7.96 mL) were added dropwise at 0°C over 30 min. Thereafter, the reaction was continued at this temperature for 4 to 48 h. The resulting viscous dark green solution was slowly poured into an ethanol-water solution. The white fibrous solid was filtered, washed with water and immersed in 1 M sodium hydroxide at room temperature for 12 h. Finally, the white fibrous product was filtered, washed with water and dried under vacuum at 80°C for 12 h. The yield of the polymer was 97%.

[0172] (2) Synthesis of alkylated polymer (FPAP-1-85). In a 50 mL single-necked flask equipped with a magnetic stirrer, the brominated polymer (1.0 g) was dissolved in 1-methyl-2-pyrrolidone (20 mL). Trimethylamine (1 mL) was quickly added. The solution was stirred at room temperature for 12 h. The resulting viscous yellow solution was added dropwise to diethyl ether. The yellow solid was filtered, washed with diethyl ether and completely dried under vacuum at 60°C. The yield of polymer FPAP-1-85 was almost 100%.

[0173] (3) FPAP-1-85 forged membrane and hydroxide ion exchange. FPAP-1-85 polymer (1.0 g) was dissolved in NMP (20 mL), cast on a glass plate or stainless steel plate, dried at 60-100°C for 5-24 h to form a membrane, and then vacuum dried at 80-150°C for 5-24 h. The membrane thickness was between 10 and 100 μm. The membrane was peeled off from the glass plate in contact with deionized water. The membrane was subjected to hydroxide ion exchange in 1 M sodium hydroxide solution at 80°C to obtain a hydroxide-form anion exchange membrane. Other FPAP-1-x membranes were prepared by using different molar ratios of 5-bromo-1,1,1-trifluoromethyl-2-one and p-terphenyl.

[0174] The synthesis formula is as follows:

[0175]

[0176] Example 3

[0177] Poly(aryl-piperidinium) was prepared from N-methyl-4-piperidone, 4-(perfluoroethyl)benzaldehyde, and p-terphenyl (designated FPAP-3-x, where x is the molar ratio of N-methyl-4-piperidone to p-terphenyl, ranging from 1 to 100). FPAP-3-x was prepared by the following three main steps:

[0178] (1) Synthesis of poly(aryl-piperidine) polymer. In a 50 mL three-necked flask equipped with a magnetic stirrer, N-methyl-4-piperidone (1.054 ml, 8.5 mmol), 4-(perfluoroethyl)benzaldehyde (0.34 g, 1.5 mmol) and p-terphenyl (2.3 g, 10 mmol) were dissolved in dichloromethane (10 mL) and trifluoroacetic acid (0.77 mL) and trifluoromethanesulfonic acid (TFSA) (7.96 mL) were added dropwise at 0°C over 30 min. Thereafter, the reaction was continued at this temperature for 4 to 48 h. The resulting viscous dark green solution was slowly poured into an ethanol-water solution. The white fibrous solid was filtered, washed with water and immersed in 1 M sodium hydroxide at room temperature for 12 h. Finally, the white fibrous product was filtered, washed with water and dried under vacuum at 80°C for 12 h. The yield of the polymer was 97%.

[0179] (2) Synthesis of alkylated polymer (FPAP-3-85). In a 50 mL single-necked flask equipped with magnetic stirring, the piperidine-functionalized polymer (1.0 g) was dissolved in 1-methyl-2-pyrrolidone (20 mL). Iodomethane (1 mL) was quickly added. The solution was stirred at room temperature for 12 h. The resulting viscous yellow solution was added dropwise to diethyl ether. The yellow solid was filtered, washed with diethyl ether and completely dried under vacuum at 60°C. The yield of polymer FPAP-3-85 was almost 100%.

[0180] (3) FPAP-3-85 forged membrane and hydroxide ion exchange. FPAP-3-85 polymer (1.0 g) was dissolved in NMP (20 mL), cast on a glass plate or stainless steel plate, dried at 60-100°C for 5-24 h to form a membrane, and then vacuum dried at 80-150°C for 5-24 h. The membrane thickness was between 10 and 100 μm. The membrane was peeled off from the glass plate in contact with deionized water. The membrane was subjected to hydroxide ion exchange in 1 M sodium hydroxide solution at 80°C to obtain a hydroxide-form anion exchange membrane. Other FPAP-3-x membranes were prepared by using different molar ratios of N-methyl-4-piperidone and p-terphenyl.

[0181] The synthesis formula is as follows:

[0182]

[0183] Example 4

[0184] Poly(aryl-piperidinium) was prepared from N-methyl-4-piperidone, 3,5-diperfluoroethylbenzaldehyde, and p-terphenyl (designated FPAP-4-x, where x is the molar ratio of N-methyl-4-piperidone to p-terphenyl, ranging from 1 to 100). FPAP-3-x was prepared by three main steps: (1) synthesis of poly(aryl-piperidine) polymer, (2) synthesis of alkylated polymer, and (3) membrane forging and hydroxide ion exchange. The structural formula is as follows:

[0185]

[0186] The molecular weight data (GPC) of this example is as follows Figure 4 shown.

[0187] Example 5

[0188] Poly(aryl-piperidinium) was prepared from N-methyl-4-piperidone, pentafluoropropionaldehyde hydrate, and m-terphenyl (designated FPAP-5-x, where x is the molar ratio of N-methyl-4-piperidone to m-terphenyl, ranging from 1 to 100). FPAP-5-x was prepared by three main steps: (1) synthesis of a poly(aryl-piperidine) polymer, (2) synthesis of an alkylated polymer, and (3) membrane forging and hydroxide ion exchange. The structural formula is as follows:

[0189]

[0190] Example 6

[0191] Poly(aryl-piperidinium) was prepared from N-methyl-4-piperidone, heptafluorobutyraldehyde hydrate, and m-terphenyl (designated FPAP-6-x, where x is the molar ratio of N-methyl-4-piperidone to m-terphenyl, ranging from 1 to 100). FPAP-6-x was prepared by three main steps: (1) synthesis of a poly(aryl-piperidine) polymer, (2) synthesis of an alkylated polymer, and (3) membrane forging and hydroxide ion exchange. The structural formula is as follows:

[0192]

[0193] Example 7

[0194] Poly(aryl-alkylene) was prepared from 1-(4-(3-bromopropyl)phenyl)-2,2,2-trifluoroethanone, pentafluoropropionaldehyde hydrate, and p-terphenyl (designated as FPAP-7-x, where x is the molar ratio of 1-(4-(3-bromopropyl)phenyl)-2,2,2-trifluoroethanone to p-terphenyl, ranging from 1 to 100). FPAP-7-x was prepared by the following three main steps: (1) synthesis of poly(aryl-alkylene) polymer, (2) synthesis of alkylated polymer, and (3) membrane forging and hydroxide ion exchange. The structural formula is as follows:

[0195]

[0196] Example 8

[0197] Poly(aryl-alkylene) was prepared from 1-(4-(3-bromopropyl)phenyl)-2,2,3,3,3-pentafluoroacetone, pentafluoropropionaldehyde hydrate, and p-terphenyl (designated FPAP-8-x, where x is the molar ratio of 1-(4-(3-bromopropyl)phenyl)-2,2,3,3,3-pentafluoroacetone to p-terphenyl, ranging from 1 to 100). FPAP-7-x was prepared by the following three main steps: (1) synthesis of poly(aryl-alkylene) polymer, (2) synthesis of alkylated polymer, and (3) membrane forging and hydroxide ion exchange. The structural formula is as follows:

[0198]

[0199] Example 9

[0200] Poly(aryl-piperidinium) was prepared from N-methyl-4-piperidone, 1-(4-(perfluoroethyl)phenyl)ethanone, and p-terphenyl (designated FPAP-9-x, where x is the molar ratio of N-methyl-4-piperidone to p-terphenyl, ranging from 1 to 100). FPAP-9-x was prepared by three main steps: (1) synthesis of a poly(aryl-piperidine) polymer, (2) synthesis of an alkylated polymer, and (3) membrane forging and hydroxide ion exchange. The synthesis equation is as follows:

[0201]

[0202] Example 10

[0203] Poly(aryl-alkylene) was prepared from 1-(4-(3-bromopropyl)phenyl)-2,2,2-trifluoroethanone, pentafluoropropionaldehyde hydrate, and p-terphenyl (designated as FPAP-10-x, where x is the molar ratio of 1-(4-(3-bromopropyl)phenyl)-2,2,2-trifluoroethanone to p-terphenyl, ranging from 1 to 100). FPAP-10-x was prepared by the following three main steps: (1) synthesis of poly(aryl-alkylene) polymer, (2) synthesis of alkylated polymer, and (3) membrane forging and hydroxide ion exchange. The structural formula is as follows:

[0204]

[0205] Example 11

[0206] Poly(aryl-alkylene) was prepared from 1-(4-(3-bromopropyl)phenyl)-2,2,2-trifluoroethanone, pentafluoropropionaldehyde hydrate, and p-terphenyl (designated as FPAP-11-x, where x is the molar ratio of 1-(4-(3-bromopropyl)phenyl)-2,2,2-trifluoroethanone to p-terphenyl, ranging from 1 to 100). FPAP-11-x was prepared by the following three main steps: (1) synthesis of poly(aryl-alkylene) polymer, (2) synthesis of alkylated polymer, and (3) membrane forging and hydroxide ion exchange. The structural formula is as follows:

[0207]

[0208] Example 12

[0209] Poly(aryl-piperidinium) was prepared from 3-oxo-6-azaspiro[5,5]undecane salt, pentafluoropropionaldehyde hydrate, and p-terphenyl (designated as FPAP-12-x, where x is the molar ratio of 3-oxo-6-azaspiro[5,5]undecane salt to p-terphenyl, ranging from 1 to 100). FPAP-12-x was prepared by three main steps: (1) synthesis of poly(aryl-piperidine) polymer, (2) synthesis of alkylated polymer, and (3) membrane forging and hydroxide ion exchange. The structural formula is as follows:

[0210]

[0211] Example 13

[0212] Poly(aryl-piperidinium) is prepared from azospiro salt, pentafluoropropionaldehyde hydrate, and p-terphenyl (designated FPAP-13-x, where x is the molar ratio of azospiro salt to p-terphenyl, ranging from 1 to 100). FPAP-13-x is prepared by three main steps: (1) synthesis of a poly(aryl-piperidine) polymer, (2) synthesis of an alkylated polymer, and (3) membrane forging and hydroxide ion exchange. The structural formula is as follows:

[0213]

[0214] Example 14

[0215] Poly(aryl-piperidinium) was prepared from N-methyl-4-piperidone, pentafluoropropionaldehyde hydrate, and QBPAF-C6 (designated FPAP-14-x, where x is the molar ratio of N-methyl-4-piperidone to QBPAF-C6, ranging from 1 to 100). FPAP-14-x was prepared by three main steps: (1) synthesis of poly(aryl-piperidinium) polymer, (2) synthesis of alkylated polymer, and (3) membrane forging and hydroxide ion exchange. The structural formula is as follows:

[0216]

[0217] Example 15

[0218] Poly(aryl-piperidinium) was prepared from N-methyl-4-piperidone, pentafluoropropionaldehyde hydrate, and 1,2-diphenylethane (designated FPAP-15-x, where x is the molar ratio of N-methyl-4-piperidone to 1,2-diphenylethane, ranging from 1 to 100). FPAP-15-x was prepared by three main steps: (1) synthesis of poly(aryl-piperidinium) polymer, (2) synthesis of alkylated polymer, and (3) membrane forging and hydroxide ion exchange. The synthesis equation is as follows:

[0219]

[0220] Example 16

[0221] Poly(aryl-piperidinium) was prepared from N-methyl-4-piperidone, pentafluoropropionaldehyde hydrate, and biphenyl (designated FPAP-16-x, where x is the molar ratio of N-methyl-4-piperidone to biphenyl, ranging from 1 to 100). FPAP-16-x was prepared by three main steps: (1) synthesis of poly(aryl-piperidine) polymer, (2) synthesis of alkylated polymer, and (3) membrane forging and hydroxide ion exchange. The synthesis equation is as follows:

[0222]

[0223] Example 17

[0224] Poly(aryl-piperidinium) was prepared from N-methyl-4-piperidone, 2,2-difluoro-2-(trifluoromethoxy)acetaldehyde hydrate, and p-terphenyl (designated FPAP-17-x, where x is the molar ratio of N-methyl-4-piperidone to p-terphenyl, ranging from 1 to 100). FPAP-17-x was prepared by three main steps: (1) synthesis of poly(aryl-piperidine) polymer, (2) synthesis of alkylated polymer, and (3) membrane forging and hydroxide ion exchange. The synthesis equation is as follows:

[0225]

[0226] Example 18

[0227] Poly(aryl-piperidinium) was prepared from N-methyl-4-piperidone, 2,2-difluoro-2-(trifluoromethylthio)acetaldehyde hydrate, and p-terphenyl (designated FPAP-18-x, where x is the molar ratio of N-methyl-4-piperidone to p-terphenyl, ranging from 1 to 100). FPAP-18-x was prepared by the following three main steps: (1) synthesis of poly(aryl-piperidine) polymer, (2) synthesis of alkylated polymer, and (3) membrane forging and hydroxide ion exchange. The synthesis equation is as follows:

[0228]

[0229] Example 19

[0230] Poly(aryl-quinuclidine) was prepared from 3-quinuclidine, pentafluoropropionaldehyde hydrate, and p-terphenyl (designated FPAP-19-x, where x is the molar ratio of 3-quinuclidine to p-terphenyl, ranging from 1 to 100). FPAP-19-x was prepared by three main steps: (1) synthesis of poly(aryl-quinuclidine) polymer, (2) synthesis of alkylated polymer, and (3) membrane forging and hydroxide ion exchange. The structural formula is as follows:

[0231]

[0232] Comparative Example 1

[0233] Poly(aryl-piperidinium) was prepared from N-methyl-4-piperidone, trifluoroacetophenone, and p-terphenyl (designated PAP-1-x, where x is the molar ratio of N-methyl-4-piperidone to p-terphenyl, ranging from 1 to 100). The preparation of PAP-1-x is similar to FPAP-1-x by the following three main steps:

[0234] (1) Synthesis of poly(aryl-piperidine) polymer. In a 250 mL three-necked flask equipped with an overhead mechanical stirrer, N-methyl-4-piperidone (10.179 g, 0.09 mol), 2,2,2-trifluoroacetophenone (1.74 g, 0.01 mol) and p-terphenyl (23 g, 0.1 mol) were dissolved in dichloromethane (60 mL) and trifluoroacetic acid (7.7 mL) and trifluoromethanesulfonic acid (TFSA) (79.6 mL) were added dropwise at 0°C over 30 min. Thereafter, the reaction was continued at this temperature for 4 to 48 h. The resulting viscous brown solution was slowly poured into an ethanol-water solution. The white fibrous solid was filtered, washed with water and immersed in 1 M sodium hydroxide at room temperature for 12 h. Finally, the white fibrous product was filtered, washed with water and dried under vacuum at 80°C for 12 h. The yield of the polymer was 97%.

[0235] (2) Synthesis of alkylated polymer (PAP-1-85). In a 50 mL single-necked flask equipped with magnetic stirring, the piperidine-functionalized polymer (1.0 g) was dissolved in 1-methyl-2-pyrrolidone (20 mL). Iodomethane (1 g) was quickly added. The solution was stirred at room temperature for 12 h. The resulting viscous yellow solution was added dropwise to diethyl ether. The yellow solid was filtered, washed with diethyl ether and dried completely under vacuum at 60°C. The yield of polymer PAP-1-85 was almost 100%.

[0236] (3) PAP-1-85 forging membrane and hydroxide ion exchange. PAP-1-85 polymer (1.0 g) was dissolved in NMP (20 mL), cast on a glass plate or stainless steel plate, dried at 60-100°C for 5-24 hours to form a membrane, and then vacuum dried at 80-150°C for 5-24 hours. The membrane thickness was between 10 and 100 μm. The membrane (in the form of iodide) was peeled off from the glass plate in contact with deionized water. The membrane was subjected to hydroxide ion exchange in 1 M sodium hydroxide solution at 80°C to obtain an anion exchange membrane in the hydroxide form. Other PAP-1-x membranes were prepared by different molar ratios of N-methyl-4-piperidone and p-terphenyl.

[0237] The synthesis formula is as follows:

[0238]

[0239] Table 1

[0240]

[0241]

[0242] From the test results in Table 1 above, it can be seen that according to the technical solution of the present invention:

[0243] According to the test results of Examples 1 to 18 and Comparative Example 1, it can be concluded that the free radical resistance stability of the product manufactured by this design is significantly improved.

[0244] According to the test results of Examples 1 to 18 and Comparative Example 1, it can be concluded that the water absorption and swelling rate of the polymer manufactured by this design are reduced.

[0245] According to the test results of Examples 1 to 18 and Comparative Example 1, it was found that under the condition of similar IEC, the ionic conductivity of the membrane manufactured by this design was improved due to the microphase separation of the membrane after the introduction of fluorine element.

[0246] Judging from the experimental data, the introduction of fluorine element can effectively reduce water absorption and swelling rate, increase microphase separation and improve ionic conductivity, which is in line with the expected effect.

[0247] The test method is as follows:

[0248] 1) Conductivity: The OH- ion conductivity of the fully wetted anion exchange membrane in pure water was measured using the four-electrode AC impedance method. The specific test parameters are as follows: a membrane material with an area of ​​5 mm × 10 mm and a thickness of 40 μm was taken. The AC impedance test was performed using a Chenhua (CHI760E) electrochemical workstation at a frequency of 1 Hz to 1000 kHz. The ionic conductivity was calculated by fitting the curve. The test temperature was 20-100°C.

[0249] 2) Water absorption rate and swelling rate: The test method refers to the water absorption rate and swelling rate method of proton exchange membrane GB / T 20042.3-2022.

[0250] 3) Ion Exchange Capacity (IEC): The IEC of the chloride ion form membrane was determined by Mohr titration. A sample weighing not less than 50.0 mg was placed in a vacuum oven at an absolute pressure of not more than 20.0 kPa and a temperature of 80°C for 8 h. The mass (m) of the dry membrane was then weighed using an analytical balance.

[0251] Ion exchange: Place the sample in a sealed reagent bottle filled with 0.5M KCl solution for 24 hours (KCl needs to be replaced 3 times), and then wash it thoroughly with deionized water to obtain a chloride ion exchange membrane.

[0252] Soak the chloride ion exchange membrane in 50.0 mL of 0.2 M sodium nitrate for 8 hours. Collect the entire sodium nitrate solution and titrate it with 0.10 M standard silver nitrate using K2CrO4 as a colorimetric indicator. Record the volume of silver nitrate solution consumed (VagNO3). Calculate the membrane's IEC value using the following formula:

[0253] IEC=CAgNO3×VAgNO3

[0254] Where:

[0255] IEC------The ion exchange capacity of the membrane, in grams per mole (g / mol);

[0256] m-------mass of dry anion exchange membrane, in grams (g);

[0257] VAgNO3----the volume of AgNO3 solution consumed in titration, in liters (L);

[0258] CAgNO3----The molar concentration of AgNO3 standard solution, in moles per liter (mol / L);

[0259] Note: Take 3 samples as a group and calculate the average value as the test result

[0260] Fenton stability test. First, measure the dry weight m0 of the membrane at 25°C, then soak the membrane in a 3% weight concentration hydrogen peroxide solution (3ppm Fe 2+ ) for 1 hour, then rinse with water to remove the solution, dry and weigh m1. Weight loss (%) = (m1-m0) / m0*100.

[0261] Alkali aging test

[0262] Films were prepared from Example 1, Example 2 and Comparative Example 1, and subjected to anti-aging tests. Figure 2 A is the picture before aging test. Figure 2 Figure B is the picture after aging test. The aging process is as follows:

[0263] The resulting membranes were placed in a 1M NaOH solution and oven-dried at 80°C for 180 days before being removed. After drying and weighing, the membranes from Comparative Example 1 became unevenly colored black, while the membranes from Examples 1 and 2 only slightly darkened. The IEC loss for Comparative Example 1 was approximately 13.3%, while the IEC loss for Examples 1 and 2 was approximately 6.1% after aging.

[0264] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A method for preparing an anion exchange resin containing a fluorinated alkyl side chain and a membrane thereof, characterized in that: The steps include: S1: dissolving an aromatic structure monomer of formula 2A, a perfluorocarbon chain structure monomer of formula 1A or formula 1B, and an optional cationic group monomer of formula 3A or 3B or 3C or 3D in an organic solvent, cooling the temperature to 0°C with an ice bath, adding a catalyst dropwise, and polymerizing at 0°C for 2 to 12 days. After the reaction is completed, a polar solvent is added to the reaction solution to quench the reaction, and the polymer is dissolved under stirring at 100°C. The dissolved mixed solution is poured into a precipitation solvent, precipitated, filtered under reduced pressure, washed with deionized water, and vacuum dried to obtain a dry white solid; S2: The dry white solid prepared above is dissolved in a polar solvent, and then alkylated with a quaternary amine or a nitrogen-containing heterocycle and an alkylating agent at room temperature for more than 12 hours. The light yellow solid is precipitated and filtered with a solvent, and then washed with distilled water and dried.

2. The method for preparing an anion exchange resin containing a fluorinated alkyl side chain according to claim 1, wherein: The structures of Formula 1A, Formula 1B, Formula 2A, Formula 3A, Formula 3B, Formula 3C, and Formula 3D in step S1 are respectively as follows:

3. The method for preparing an anion exchange resin containing a fluorinated alkyl side chain according to claim 2, wherein: The R1 are each independently selected from one or more of the following structures: k represents an integer between 1 and 10; Said R2 is selected from hydrogen or methyl; Said R3, R4, R5 and R6 are each independently any one of hydrogen, halide, alkyl, alkenyl, alkynyl, and aryl, and said alkyl, alkenyl, alkynyl or aryl is optionally substituted with halide; R8, R9, R 10 、R 11 and R 12 are each independently an alkyl group; In Formula 2A, the dotted portion is present or absent. When the dotted portion is absent, R7 is absent. When the dotted portion is present, R7 is an alkyl group, an alkenyl group, or an alkynyl group, and the alkyl group, the alkenyl group, or the alkynyl group is optionally substituted with a halide. The R 20 、R 30 、R 40 、R 50 、R 60 、R 70 、R 80 and R 90 are each independently any one of hydrogen, halide, alkyl, alkenyl, alkynyl, and aryl, and the alkyl, alkenyl, alkynyl, or aryl is optionally substituted with halide, and wherein R 30 and R 60 an optionally attached halide or alkyl-substituted five- or six-membered ring; The R 13 is oxygen, sulfur, nitrogen, alkyl, alkenyl, alkynyl, or a substituent having the following structure: R 110 、R 120 、R 130 and R 140 Each is independently any one of hydrogen, halide, alkyl, alkenyl, alkynyl, and aryl, and the alkyl, alkenyl, alkynyl, or aryl is optionally substituted with halide; R 100 is a cation exchange group; n represents an integer between 0 and 5; m represents an integer between 0 and 10; p represents an integer between 0 and 10; The cation exchange group is a quaternary ammonium or a nitrogen-containing heterocycle: in: R 17 are each independently an alkyl group; R 14 、R 15 、R 16 、R 18 and R 19 Each is independently any one of alkyl, alkenyl, aryl, and alkynyl; a is 0, 1, 2, 3, 4, 5, or 6; R' is a nitrogen-containing heterocyclic ring; The nitrogen-containing heterocycle comprises optionally substituted pyrrole, pyrroline, pyrazole, pyrazoline, imidazole, imidazoline, triazole, pyridine, triazine, pyrazine, pyridazine, pyrimidine, azepine, quinoline, piperidine, pyrrolidine, pyrazolidine, imidazolidine, wherein each substituent is independently alkyl, alkenyl, alkynyl or aryl; Nitrogen-containing heterocyclic groups include imidazolium groups having (Formula 4): Where: R 150 、R 160 、R 170 and R 180 Each is independently any one of hydrogen, halide, alkyl, alkenyl, alkynyl, and aryl, and the alkyl, alkenyl, alkynyl, or aryl is optionally substituted with halide; X - Anion: Br - , I - 、Cl - OH - 、HCO3 - .

4. The method for preparing an anion exchange resin containing a fluorinated alkyl side chain according to claim 1, wherein: The organic solvent in step S1 is one or a combination of dichloromethane, dichloroethane, trifluoroacetic acid, trifluoromethanesulfonic acid, chloroform, 1,1,2,2-tetrachloroethane, and dimethylacetamide.

5. The method for preparing an anion exchange resin containing a fluorinated alkyl side chain according to claim 1, wherein: The catalyst in step S1 is one of trifluoromethanesulfonic acid, pentafluoroethanesulfonic acid, heptafluoro-1-propanesulfonic acid, trifluoroacetic acid, perfluoropropionic acid, heptafluorobutyric acid, or a combination thereof.

6. The method for preparing an anion exchange resin containing a fluorinated alkyl side chain according to claim 1, characterized in that: The polar solvent described in step S1 and step S2 is the same, which is one of NMP, DMF, DMSO, and DMAc.

7. The method for preparing an anion exchange resin containing a fluorinated alkyl side chain according to claim 1, characterized in that: The precipitation solvent in step S1 is one of water, methanol, ethanol, propanol, isopropanol, butanol, isobutanol, amyl alcohol, tetrahydrofuran, or a combination thereof.

8. The method for preparing an anion exchange resin containing a fluorinated alkyl side chain according to claim 1, wherein: The basic structure of the quaternary amine or nitrogen-containing heterocycle described in step S2 is as follows: in: R 17 are each independently an alkylene group; R 14 、R 15 、R 16 、R 18 and R 19 Each is independently any one of alkyl, alkenyl, aryl, and alkynyl; a is 0, 1, 2, 3, 4, 5, or 6; R' is a nitrogen-containing heterocyclic ring. The nitrogen-containing heterocycle comprises optionally substituted pyrrole, pyrroline, pyrazole, pyrazoline, imidazole, imidazoline, triazole, pyridine, triazine, pyrazine, pyridazine, pyrimidine, azepine, quinoline, piperidine, pyrrolidine, pyrazolidine, imidazolidine, wherein each substituent is independently alkyl, alkenyl, alkynyl or aryl; The nitrogen-containing heterocyclic group may include an imidazolium having (Formula 4). Where: R 150 、R 160 、R 170 and R 180 Each is independently any one of hydrogen, halide, alkyl, alkenyl, alkynyl, and aryl, and the alkyl, alkenyl, alkynyl, or aryl is optionally substituted with halide. X - Anion: Br - , I - 、Cl - OH - 、HCO3 - .

9. The method for preparing an anion exchange resin containing a fluorinated alkyl side chain according to claim 1, wherein: The solvent in step S2 is one or a combination of ethyl acetate, propyl acetate, n-butyl acetate, and isobutyl acetate; The alkylating agent is one of iodomethane, iodoethane, 1-iodopropane, 1-iodobutane, 1-iodopentane, 1-iodohexane, 1,10-dibromodecane, bromomethane, bromoethane, 1-bromopropane, 1-bromobutane, 1-bromopentane, 1-bromohexane, chloromethane, chloroethane, 1-chloropropane, 1-chlorobutane, 1-chloropentane, 1-chlorohexane, 1,3-dibromopropane, 1,4-dibromobutane, 1,5-dibromopentane, 1,6-dibromohexane, 1,7-dibromoheptane, 1,3-diiodopropane, 1,4-diiodobutane, 1,5-diiodopentane, 1,6-diiodohexane, 1,7-diiodoheptane, methyl trifluoromethanesulfonate, methyl methanesulfonate, methyl fluorosulfonate, 1,2-dimethylhydrazine, trimethyl phosphate, and dimethyl sulfate, or a combination thereof.

10. An anion exchange membrane, characterized in that The invention is prepared by using the anion exchange resin containing a fluorinated alkyl side chain according to any one of claims 1 to 8.

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