Anion exchange polymers and membranes for electrolysis

Abstract

The anion exchange polymer comprises a plurality of repeating units of formula (I). The polymer may be synthesized from a superacid catalyzed polyhydroxyalkylation reaction of monomers Ar1 'and X1' to form a neutral precursor polymer followed by a Menshutkin reaction to convert the neutral precursor polymer to the anion exchange polymer having halide-based counterions, and followed by an ion exchange reaction to convert the anion exchange polymer having the halide-based counter ion to an acetate (CH3COO-), trifluoroacetate (CF3COO-), propionate (CH3CH2COO-) or butyrate anion (CH3CH2CH2COO-) counter ion. # imgabs0 # also describes anion exchange membranes and membrane electrode assemblies incorporating anion exchange polymers.

Description

[0001] Priority Statement

[0002] This application claims the benefit and priority of U.S. Patent Application No. 18 / 064,569, filed on December 9, 2022, the entire disclosure of which provisional patent application is incorporated herein by reference. Background Art

[0003] Hydrogen plays an important role in the path towards an environmentally friendly low-carbon energy structure as an energy carrier for grid balancing or power-to-gas and power-to-liquid processes. Water electrolysis produces high-quality hydrogen by electrochemically decomposing water into hydrogen and oxygen; this reaction is given by Equation 1 below. The water electrolysis process is endothermic, and electricity is the energy source. When this method is operated with renewable energy sources such as wind, solar, or geothermal energy, water electrolysis has a zero carbon footprint. The main water electrolysis technologies include alkaline electrolysis, proton exchange membrane (PEM) water electrolysis (such as Figure 1 PEMWE as shown), anion exchange membrane (AEM) water electrolysis (such as Figure 2 AEMWE as shown), and solid oxide water electrolysis.

[0004] As Figure 1 shown in PEMWE system 100, the anode 105 and the cathode 110 are separated by a solid PEM electrolyte 115, such as a sulfonated tetrafluoroethylene-based cofluoropolymer sold under the trademark by Chemours company. The anode and cathode catalysts typically comprise IrO2 and Pt, respectively. At the positively charged anode 105, pure water 120 is oxidized to produce oxygen 125, electrons (e - ) and protons; this reaction is given by Equation 2. Protons are transported from the anode 105 to the cathode 110 through the proton-conducting PEM 115. At the negatively charged cathode 110, a reduction reaction occurs, where electrons from the cathode 110 are given to protons to form hydrogen 130; this reaction is given by Equation 3. The PEM 115 not only conducts protons from the anode 105 to the cathode 110 but also separates the H2 gas 130 and O2 gas 125 produced in the water electrolysis reaction. PEM water electrolysis is one of the advantageous methods for converting renewable energy into high-purity hydrogen, with the advantages of a compact system design under high pressure difference, high current density, high efficiency, fast response, small footprint, low-temperature (20 °C - 90 °C) operation, and high-purity oxygen by-products. However, one of the main challenges of PEM water electrolysis is the high capital cost of the cell stack, including expensive acid-resistant stack hardware (such as Pt-coated Ti bipolar plates), expensive noble metal catalysts required for the electrodes, and expensive PEMs.

[0005] Water electrolysis reaction: 2H2O → 2H2 + O2 (1)

[0006] Anodic oxidation reaction of PEMWE: 2 H2O → O2 + 4H + + 4e - (2)

[0007] Cathodic reduction reaction of PEMWE: 2H + + 2e - → H2 (3)

[0008] AEMWE is a developing technology. As Figure 2 shown, in AEMWE system 200, anode 205 and cathode 210 are separated by a solid AEM electrolyte 215. Generally, a water feed 220 with an added electrolyte (such as diluted KOH or K2CO3 or deionized water) is fed to the cathode side. Anode and cathode catalysts generally include Ni-based or Ni-alloy catalysts without platinum group metals. At the negatively charged cathode 210, water is reduced by adding four electrons to form hydrogen gas 225 and hydroxide ions; this reaction is given by Equation 4. The hydroxide ions diffuse from the cathode 210 to the anode 205 through the AEM 215 that conducts hydroxide ions. At the positively charged anode 205, the hydroxide ions recombine to form water and oxygen 230; this reaction is given by Equation 5. The AEM 215 not only conducts the hydroxide ions from the cathode 210 to the anode 205, but also separates the H2 225 and O2 230 generated in the water electrolysis reaction. The AEM 215 allows the preparation of hydrogen gas 225 with a very high purity of at least 99.9% at a high pressure of up to 35 bar.

[0009] Cathodic reduction reaction of AEMWE: 4 H2O + 4e - → 2 H2 + 4OH - (4)

[0010] Anodic oxidation reaction of AEMWE: 4OH - → 2 H2O + O2 + 4e - (5)

[0011] AEMWE has advantages over PEMWE because it allows the use of cheaper catalysts without platinum group metals, such as Ni and Ni-alloy catalysts. In addition, much cheaper stainless steel bipolar plates can be used in the gas diffusion layer (GDL) of AEMWE instead of the expensive Pt-coated Ti bipolar plates currently used in PEMWE. However, the biggest obstacles to developing AEM systems are the membrane hydroxide ion conductivity and stability, as well as the lack of understanding of how to integrate catalysts into AEM systems. Research on AEMWE in the literature focuses on developing electrocatalysts, AEMs, and understanding the operating mechanism, with the general aim of obtaining an efficient, low-cost, and stable AEMWE technology.

[0012] Fuel cells, as the next generation of clean energy, convert the energy of chemical reactions such as the oxidation / reduction redox reaction of hydrogen and oxygen into electrical energy. The three main types of fuel cells are alkaline electrolyte fuel cells, polymer electrolyte membrane fuel cells, and solid oxide fuel cells. Polymer electrolyte membrane fuel cells can include proton exchange membrane fuel cells (PEMFCs), anion exchange membrane fuel cells (AEMFCs), and direct methanol fuel cells. PEMFCs use a PEM to conduct protons from the anode to the cathode, and it also separates H2 gas and O2 gas to prevent gas crossover. AEMFCs use an AEM to conduct OH - from the cathode to the anode, and it also separates H2 gas and O2 gas to prevent gas crossover.

[0013] The anode in an electrochemical cell is the electrode where the main reaction is oxidation (e.g., the water oxidation / oxygen evolution reaction electrode for a water electrolyzer, or the hydrogen oxidation electrode for a fuel cell). The cathode in an electrochemical cell is the electrode where the main reaction is reduction (e.g., the proton reduction / hydrogen evolution reaction electrode for a water electrolyzer, or the oxygen reduction electrode for a fuel cell). The membrane is one of the key materials that make up an electrolyzer or a fuel cell and is an important driver of safety and performance. Some important properties of the membranes used in fuel cells and membrane electrolysis include high conductivity, high ionic permeability, high ion exchange capacity (for ion exchange membranes), high ion / H2 and O2 selectivity (low H2 and O2 permeability / crossover), low price, low area resistance that minimizes the efficiency loss caused by ohmic polarization, high tolerance to oxidation and reduction conditions, chemical inertness over a wide pH range, high thermal stability, and high proton conductivity and high mechanical strength (thickness, low swelling).

[0014] For AEM water electrolysis and AEMFCs, which have wide applications in renewable energy systems, significant progress is needed in terms of high cost-effectiveness, high performance, stable catalysts, membrane materials, and other fuel cell stack components. Brief Description of the Drawings

[0015] Figure 1 is a diagram of an embodiment of a PEMWE cell.

[0016] Figure 2 is a diagram of an embodiment of an AEMWE cell.

[0017] Figure 3 is a diagram of an embodiment of the synthesis of poly(triphenylbenzene-co-phenanthrenepiperidinium acetate) anion exchange polymer (abbreviated as PTPP-OAc).

[0018] Figure 4Graph of the polarization curves of a single water electrolysis cell comprising (a) a Pt / PAPP-OAc 2-layer MEA or (b) a Pt / PAPP-HCO3 2-layer MEA prepared according to the present invention. Detailed Description

[0019] Novel anion exchange polymers comprising multiple repeating units of formula (I)

[0020]

[0021] Previously developed for the preparation of AEMs. The anion exchange polymers have a stable hydrophobic polymer backbone that includes linear aromatic units (such as biphenyl and terphenyl) and polycyclic aromatic units (such as naphthalene and phenanthrene). Cationic groups, such as piperidinium, quaternized carbazole derivatives, quaternized phenothiazine derivatives, or piperidinium salts, are covalently incorporated into the polymer for the preparation of novel AEMs. Thus, these polymers provide high OH - conductivity, high chemical stability, low swelling in alkaline water at 60 °C to 120 °C, and high mechanical stability. The anion exchange polymers can be used in electrolysis, such as water or CO2 electrolysis, and other applications such as redox flow batteries and fuel cell applications.

[0022] The anion exchange polymers are designed to achieve high OH - conductivity by incorporating piperidinium, or piperidinium salts, or both into the polymer side chains; high chemical stability by having a polymer backbone free of ether bonds; and high mechanical strength due to high polymer backbone rigidity and molecular weight by incorporating both linear aromatic units (such as biphenyl and terphenyl) and polycyclic aromatic units (such as naphthalene and phenanthrene) into the polymer backbone. The polymer has hydrophilic anion exchange functional groups (such as piperidinium functional groups) on the polymer side chains and a stable hydrophobic polymer backbone free of ether bonds that includes linear aromatic units (such as biphenyl and terphenyl) and polycyclic aromatic units (such as naphthalene and phenanthrene), which enables efficient and stable operation in water or CO2 electrolysis, redox flow batteries, and fuel cell applications.

[0023] However, it has been found that some poly(arylpiperidinium) anion exchange polymers derived from aromatic hydrocarbons and 4-piperidone tend to have low or very poor solubility in common organic solvents, even polar solvents (such as dimethyl sulfoxide (DMSO) and N-methylpyrrolidone (NMP), etc.). Thus, it has proven challenging to dissolve polymers with iodide counterions in organic solvents and maintain the solution stable. In some cases, the polymer solutions are unstable and prone to discoloration due to oxidation. It has been found that having OH -Poly(arylpiperidinium)-based anion exchange polymers with counterions are unstable in the presence of O2. Anion exchange polymers based on poly(arylpiperidinium) with bicarbonate (HCO3 - ) counterions are insoluble in most organic solvents commonly used for membrane fabrication, such as NMP, dimethylformamide (DMF), DMSO, and dimethylacetamide (DMAc), although they are stable. Additionally, anion exchange polymers based on poly(arylpiperidinium) with HCO3 - counterions are soluble in some alcohols, such as ethanol. However, their solubility in alcohols leads to compatibility issues with formulations for catalyst coatings on membranes, which contain polycyclic aromatic hydrocarbon-based anion exchange polymers with HCO3 - counterions, which is important for the preparation of catalyst-coated membranes. Ethanol or other alcohol solvents used in catalyst ink formulations may potentially damage or partially dissolve anion exchange membranes prepared from poly(arylpiperidinium)-based anion exchange polymers with HCO3 - counterions.

[0024] The solubility and solution stability of poly(arylpiperidinium)-based anion exchange polymers in common organic solvents (such as DMSO) can be improved, for example, by converting the original poly(arylpiperidinium)-based anion exchange polymer from its iodide form (where iodide is the anion counterion) to the acetate form (acetate anion as the counterion). This is achieved through an ion exchange process.

[0025] Anion exchange polymers and polymer solutions containing them have many benefits. The unique solubility properties of the polymers make them promising anion exchange polymers for the preparation of anion exchange membranes. Poly(arylpiperidinium)-based anion exchange polymers with specified counterions have improved solubility in common organic solvents (such as NMP, DMF, DMSO, and DMAc). Additionally, the stability of the polymer solutions used to prepare anion exchange membranes is also improved. Poly(arylpiperidinium)-based anion exchange polymers with acetate (CH3COO - ), trifluoroacetate (CF3COO - ), propionate (CH3CH2COO - ), or butyrate (CH3CH2CH2COO - ) anions as counterions also have unique solubility curves, which are beneficial for membrane casting and catalyst coating on their membranes.

[0026] One aspect of the invention is an anion exchange polymer. In one embodiment, the polymer comprises a plurality of repeating units of formula (I)

[0027]

[0028] wherein Ar1 is selected from the group consisting of:

[0029]

[0030]

[0031] and mixtures thereof;

[0032] X1 is selected from the group consisting of:

[0033]

[0034] optionally and mixtures thereof;

[0035] wherein Y1 - or Y2 - or both are

[0036] wherein R1 to R 28 are each independently hydrogen, a halide, an alkyl group, an alkenyl group, an alkynyl group or an aryl group, and the alkyl group, alkenyl group, alkynyl group or aryl group is optionally substituted by a halide or a positively charged functional group;

[0037] wherein R 29 to R 31 are each independently hydrogen, an alkyl group, an alkenyl group, an alkynyl group or an aryl group, and the alkyl group, alkenyl group, alkynyl group or aryl group is optionally substituted by a halide or a positively charged functional group;

[0038] wherein R 32 is an alkyl group, an alkenyl group, an alkynyl group or an aryl group, and the alkyl group, alkenyl group, alkynyl group or aryl group is optionally substituted by a halide or a positively charged functional group;

[0039] wherein R 50 is CH3, CF3, CH3CH2 or CH3CH2CH2;

[0040] wherein A is O, S or NR 100 ;

[0041] wherein R 100 is hydrogen, an alkyl group, an alkenyl group, an alkynyl group or an aryl group, and the alkyl group, alkenyl group, alkynyl group or aryl group is optionally substituted by a halide or a positively charged functional group;

[0042] wherein n is an integer from 10 to 1000;

[0043] where p is 1, 2, 3, or 4;

[0044] where q is 0, 1, 2, or 3; and

[0045] where t is 1, 2, 3, 4, 5, or 6.

[0046] In some embodiments, Ar1 is selected from the group consisting of:

[0047]

[0048] and mixtures thereof.

[0049] In some embodiments, Ar1 is selected from the group consisting of:

[0050]

[0051] and mixtures thereof.

[0052] In some embodiments, Ar1 is selected from the group consisting of:

[0053]

[0054] and mixtures thereof;

[0055] where R 25 、R 26 、R 27 and R 28 are each independently -H or -CH3;

[0056] where p is 1 or 2; and

[0057] where q is 0 or 1.

[0058] In some embodiments, Ar1 is selected from the group consisting of:

[0059]

[0060] and mixtures thereof.

[0061] In some embodiments, Ar1 is selected from the group consisting of:

[0062]

[0063] and mixtures thereof.

[0064] In some embodiments, X1 is

[0065]

[0066] where R30 and R 31 each independently is -H, -CH3, -CH2CH3, -CH(CH3)2, -C(CH3)3, -CH2-C6H5 or -CH2-CH(CH3)2,

[0067] wherein Y1 - is and

[0068] wherein R 50 is CH3, CF3, CH3CH2 or CH3CH2CH2.

[0069] In some embodiments, X1 is

[0070]

[0071] wherein t is 1, 2, 3, 4, 5 or 6,

[0072] wherein Y2 - is and

[0073] wherein R 50 is CH3, CF3, CH3CH2 or CH3CH2CH2.

[0074] In some embodiments, X1 is a mixture of the following items

[0075]

[0076] wherein R 30 and R 31 each independently is -H, -CH3, -CH2CH3, -CH(CH3)2, -C(CH3)3, -CH2-C6H5 or -CH2-CH(CH3)2;

[0077] wherein t is 1, 2, 3, 4, 5 or 6;

[0078] wherein Y1 - and Y2 - is and

[0079] wherein R 50 is CH3, CF3, CH3CH2 or CH3CH2CH2.

[0080] In some embodiments, a polymer comprising multiple repeating units of formula (I) is formed by a superacid-catalyzed polyhydroxyalkylation reaction of monomers Ar1' and X1', followed by a Menshutkin reaction and an ion exchange reaction, wherein Ar1' is selected from the group consisting of:

[0081]

[0082]

[0083] and their mixtures; and

[0084] X1' is selected from the group consisting of:

[0085]

[0086] optionally and their mixtures;

[0087] wherein Y2 - is

[0088] wherein R 50 is CH3, CF3, CH3CH2 or CH3CH2CH2;

[0089] wherein R1 to R 28 are each independently hydrogen, a halide, an alkyl group, an alkenyl group, an alkynyl group or an aryl group, and the alkyl group, alkenyl group, alkynyl group or aryl group is optionally substituted with a halide or a positively charged functional group;

[0090] wherein R 29 and R 30 are each independently hydrogen, an alkyl group, an alkenyl group, an alkynyl group or an aryl group, and the alkyl group, alkenyl group, alkynyl group or aryl group is optionally substituted with a halide or a positively charged functional group;

[0091] wherein R 32 is an alkyl group, an alkenyl group, an alkynyl group or an aryl group, and the alkyl group, alkenyl group, alkynyl group or aryl group is optionally substituted with a halide or a positively charged functional group;

[0092] wherein A is O, S or NR 100 ;

[0093] wherein R 100 is hydrogen, an alkyl group, an alkenyl group, an alkynyl group or an aryl group, and the alkyl group, alkenyl group, alkynyl group or aryl group is optionally substituted with a halide or a positively charged functional group;

[0094] wherein p is 1, 2, 3 or 4;

[0095] wherein q is 0, 1, 2 or 3; and

[0096] wherein t is 1, 2, 3, 4, 5 or 6.

[0097] In some embodiments, Ar1' is selected from the group consisting of:

[0098]

[0099] and mixtures thereof.

[0100] In some embodiments, Ar1' is selected from the group consisting of:

[0101]

[0102] and mixtures thereof.

[0103] In some embodiments, Ar1' is selected from the group consisting of:

[0104]

[0105] and mixtures thereof;

[0106] wherein R 25 , R 26 , R 27 and R 28 are each independently -H or -CH3; where p is 1 or 2; and

[0107] where q is 0 or 1.

[0108] In some embodiments, Ar1' is selected from the group consisting of:

[0109]

[0110] and mixtures thereof.

[0111] In some embodiments, Ar1' is selected from the group consisting of:

[0112]

[0113] and mixtures thereof.

[0114] In some embodiments, X1' is

[0115]

[0116] and wherein R 30 is -H, -CH3, -CH2CH3, -CH(CH3)2, -C(CH3)3, -CH2-C6H5 or -CH2-CH(CH3)2.

[0117] In some embodiments, X1' is

[0118]

[0119] where t is 1, 2, 3, 4, 5 or 6,

[0120] where Y2 - is and

[0121] where R 50 is CH3, CF3, CH3CH2 or CH3CH2CH2.

[0122] In some embodiments, X1' is a mixture of the following

[0123]

[0124] where R 30 is -H, -CH3, -CH2CH3, -CH(CH3)2, -C(CH3)3, -CH2-C6H5 or -CH2-CH(CH3)2;

[0125] where t is 1, 2, 3, 4, 5 or 6,

[0126] where Y2 - is and

[0127] where R 50 is CH3, CF3, CH3CH2 or CH3CH2CH2.

[0128] The anion exchange polymer comprising multiple repeating units of formula (I) can be synthesized in three steps: 1) a superacid-catalyzed polyhydroxyalkylation reaction of monomer Ar1’ with X1' (such as a mixture of terphenyl and phenanthrene as Ar1’ and N-methylpiperidone as X1') to form a neutral precursor polymer; 2) a Menshutkin reaction to convert the neutral precursor polymer having a functional group (such as a piperidine-based group) into an anion exchange polymer comprising multiple repeating units of formula (I) having an anion-conducting functional group (such as a piperidinium-based cationic group and a halide-based counterion); and 3) an ion exchange reaction to convert the anion exchange polymer comprising multiple repeating units of formula (I) having a halide-based counterion into an acetate (CH3COO - ), trifluoroacetate (CF3COO - ), propionate (CH3CH2COO - ), or butyrate anion (CH3CH2CH2COO - ) counterion. Optionally, after forming the polymer into a membrane, by soaking in an alkaline solution, the anion exchange polymer having an anion-conducting functional group (such as a piperidinium-based cationic group and a negatively charged acetate (CH3COO- ) trifluoroacetate (CF3COO - ), propionate (CH3CH2COO - ), or butyrate anion (CH3CH2CH2COO - ) counterions)) is converted to an anion exchange polymer containing multiple repeating units of formula (I) having an anion conducting functional group (such as a piperidinium-based cationic group and a negatively charged hydroxide (HO - ) ion) containing multiple repeating units of formula (I).

[0129] The three-step reaction of monomer Ar1' with monomer X1' provides an anion exchange polymer having a polymer backbone free of ether bonds, which achieves high chemical stability of the polymer. Incorporating the electron-rich monomer Ar1' into the anion exchange polymer provides a hydrophobic polymer backbone free of ether bonds, and incorporating the monomer X1' into the anion exchange polymer provides a piperidinium derivative or a piperidinium salt derivative anion conducting functional group or both, which helps to achieve stable high OH - conductivity. Incorporating the monomer Ar1' into the anion exchange polymer provides a polymer having high mechanical strength due to high polymer backbone rigidity and molecular weight. Incorporating the negatively charged acetate (CH3COO - ), trifluoroacetate (CF3COO - ), propionate (CH3CH2COO - ), or butyrate anion (CH3CH2CH2COO - ) counterions into the anion exchange polymer provides improved solubility of the polymer in common organic solvents (e.g., NMP, DMF, DMSO, and DMAc). An anion exchange membrane prepared from an anion exchange polymer containing multiple repeating units of formula (I) having an anion conducting functional group (such as a piperidinium-based cationic group) and a negatively charged acetate (CH3COO - ), trifluoroacetate (CF3COO - ), propionate (CH3CH2COO - ), or butyrate anion (CH3CH2CH2COO - ) counterions has good compatibility with the catalyst ink coated on the membrane surface to form a catalyst-coated membrane. The combination of a hydrophobic polymer backbone with high mechanical strength, hydrophilic polymer side chains, and a basic-stable hydrophilic piperidinium cationic group provides a novel anion exchange polymer membrane with high OH - conductivity, high chemical stability, high mechanical strength, and long-term performance stability.

[0130] The hyperacid-catalyzed polyhydroxyalkylation reaction can be carried out at -10 °C to 50 °C, or at -5 °C to 30 °C, or at -5 °C to 25 °C for 2 h to 72 h, or 10 h to 48 h, or 12 h to 24 h. Suitable hyperacid catalysts include, but are not limited to, trifluoromethanesulfonic acid (CF3SO3H (TFSA)), methanesulfonic acid (MSA), fluorosulfuric acid (FSO3H), or mixtures thereof. The solvents used for the polyhydroxyalkylation reaction are those that can dissolve one or more of the monomers in the monomer. Suitable solvents include, but are not limited to, dichloromethane, chloroform, trifluoroacetic acid (TFA), or mixtures thereof.

[0131] The Menshutkin reaction is used to react a neutral precursor polymer with an alkyl halide, or first with an alkylamine and then with an alkyl halide to convert the neutral precursor polymer into an anion exchange polymer containing a plurality of repeating units of formula (I) (which has linear aromatic units (such as biphenyl and terphenyl) or polycyclic aromatic units (such as naphthalene and phenanthrene) and stable cation-conducting functional groups (such as piperidinium, quaternized carbazole derivatives, quaternized phenothiazine derivatives, and piperidinium salts)). Suitable alkyl halides include, but are not limited to, iodoalkanes or bromoalkanes. Suitable alkylamines include, but are not limited to, trimethylamine or triethylamine. The Menshutkin reaction can be carried out at 10 °C to 80 °C, or at 20 °C to 30 °C for 2 h to 72 h, or 10 h to 48 h, or 12 h to 24 h. The solvents used for the Menshutkin reaction are those that can dissolve the neutral precursor polymer. Suitable solvents include, but are not limited to, N-methylpyrrolidone (NMP), N,N-dimethylacetamide (DMAC), N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), 1,3-dioxolane, or mixtures thereof.

[0132] Ion exchange reaction is used to convert an anion exchange polymer containing a plurality of repeating units of formula (I) having linear aromatic units (such as biphenyl and terphenyl) or polycyclic aromatic units (such as naphthalene and phenanthrene), stable cation-conducting functional groups, and halide-based counterions into an anion exchange polymer having linear aromatic units (such as biphenyl and terphenyl) or polycyclic aromatic units (such as naphthalene and phenanthrene), stable cation-conducting functional groups, and acetate (CH3COO - ), trifluoroacetate (CF3COO - ), propionate (CH3CH2COO - ), or butyrate anions (CH3CH2CH2COO -)An anion exchange polymer containing counterions and having multiple repeating units of formula (I). The ion exchange reaction can be carried out in an acidic aqueous solution (such as an aqueous solution of acetic acid, trifluoroacetic acid, propionic acid or butyric acid) or an aqueous solution of a salt of an acid (such as potassium acetate) with a concentration of 0.2 wt% to 10 wt% or 0.5 wt% to 2 wt% at 20 °C to 60 °C or at 20 °C to 30 °C for 0.5 h to 72 h, or 0.5 h to 6 h, or 0.5 h to 1 h.

[0133] The anion exchange polymer containing multiple repeating units of formula (I) has a weight average molecular weight in the range of 10,000 daltons to 1,000,000 daltons or in the range of 50,000 daltons to 500,000 daltons.

[0134] Another aspect of the present invention is an anion exchange membrane containing the above polymer. The anion exchange membrane can be used in a variety of applications, including but not limited to fuel cells, electrolyzers, flow batteries, electrodialyzers, waste metal recovery systems, electrocatalytic hydrogen production systems, desalination devices, water purifiers, wastewater treatment systems, ion exchangers or CO2 separators.

[0135] In some embodiments, the anion exchange membrane includes a non-porous symmetric dense membrane, a dense skin asymmetric membrane, a reinforced composite membrane or a thin film composite membrane. "Dense" means that the membrane does not have pores larger than 1 nm.

[0136] In some embodiments, the reinforced composite membrane or the thin film composite membrane contains a porous substrate membrane impregnated or coated with an anion exchange polymer. The porous substrate membrane is made of a polymer different from the anion exchange polymer.

[0137] In some embodiments, the non-porous symmetric dense membrane, the dense skin asymmetric membrane, the reinforced composite membrane or the thin film composite membrane can be a flat sheet membrane.

[0138] In some embodiments, a method for preparing a non-porous symmetric dense membrane anion exchange membrane includes the following steps: 1) dissolving an anion exchange polymer in a solvent to form a polymer casting solution; 2) casting the polymer casting solution on a non-porous substrate to form a uniform layer of the polymer casting solution; 3) drying the polymer casting solution layer at 50 °C to 180 °C, or 50 °C to 120 °C, or 80 °C to 120 °C to form a dry membrane on the non-porous substrate; and optionally, 4) replacing the acetate (CH3COO - )、trifluoroacetate (CF3COO - )、propionate (CH3CH2COO - ) or butyrate (CH3CH2CH2COO -)Anions are ion-exchanged with hydroxide anions to form a non-porous symmetric dense membrane anion exchange polymer membrane. When the membrane is used in a desired application, the non-porous substrate is removed from the membrane. The solvent used to dissolve the anion exchange polymer can be selected from, but not limited to, NMP, DMAC, DMF, DMSO, 1,3-dioxolane, or mixtures thereof. The non-porous substrate used to fabricate the non-porous symmetric dense membrane can be selected from, but not limited to, glass plates, polyolefin membranes, polyimide membranes (such as membrane), polyester membranes (such as membrane), or fluorocarbon-based polymer membranes (such as poly(tetrafluoroethylene) (PTFE) membranes and poly(vinylidene fluoride) (PVDF) membranes).

[0139] In some embodiments, a method comprising the following steps is used to prepare a dense skin asymmetric anion exchange membrane: 1) preparing an anion exchange polymer membrane casting solution that comprises an anion exchange polymer of formula (I), a water-miscible solvent that can dissolve the anion exchange polymer, and a non-solvent that cannot dissolve the anion exchange polymer; 2) casting a layer of the anion exchange polymer membrane casting solution onto a support substrate; 3) evaporating the solvent and non-solvent from the surface of the coated layer and then coagulating the coated polymer layer in a coagulation bath to form a dense skin asymmetric membrane structure; 5) drying the membrane at 50 °C to 150 °C, or 50 °C to 120 °C, or 80 °C to 120 °C; and optionally, 6) ion-exchanging the acetate (CH3COO - ), trifluoroacetate (CF3COO - ), propionate (CH3CH2COO - ), or butyrate (CH3CH2CH2COO - ) anions of the anion exchange polymer in the membrane with hydroxide anions to form a dense skin asymmetric anion exchange polymer membrane. In some embodiments, when the membrane is used in a desired application, the support substrate is removed from the membrane. In some embodiments, the support substrate is part of the final dense skin asymmetric anion exchange polymer membrane. The support substrate can include polyolefins (such as polypropylene and polyethylene), polyesters, polyamides (such as nylon 6 and nylon 6,6), cellulose, or fluorocarbon-based polymers (such as PTFE and PVDF). The solvents used to prepare the dense skin asymmetric membrane include, but are not limited to, NMP, DMAC, DMF, DMSO, dioxane, 1,3-dioxolane, and mixtures thereof. The non-solvents used to prepare the dense skin asymmetric membrane include, but are not limited to, acetone, methanol, ethanol, tetrahydrofuran (THF), toluene, n-octane, n-decane, lactic acid, citric acid, isopropyl alcohol, and mixtures thereof. The dense skin asymmetric membrane can have a thin non-porous dense layer of less than 500 nm located on a microporous support layer.

[0140] In some embodiments, a method comprising the following steps is used to prepare a reinforced composite anion exchange membrane: 1) Dissolve an anion exchange polymer in a solvent to form a polymer solution; 2) Impregnate a porous matrix support membrane with the anion exchange polymer via dip coating, soaking, spraying, painting, or other known conventional solution impregnation methods to fill the pores with the anion exchange polymer; 3) Dry the impregnated membrane at 50 °C to 150 °C, or 50 °C to 120 °C, or 80 °C to 120 °C; and optionally, 4) Perform an ion exchange of the acetate (CH3COO - ), trifluoroacetate (CF3COO - ), propionate (CH3CH2COO - ), or butyrate (CH3CH2CH2COO - ) anions of the anion exchange polymer in the pores of the reinforced membrane with hydroxide anions to form a reinforced composite anion exchange membrane having interconnected anion exchange polymer domains in the porous matrix. Solvents suitable for preparing thin film composite anion exchange membranes include, but are not limited to, NMP, DMAC, DMF, DMSO, dioxane, 1,3-dioxolane, and mixtures thereof. The porous matrix should have good thermal stability (stable up to at least 120 °C), high stability under high pH conditions (e.g., pH greater than 8), high tolerance to oxidative and reductive conditions (insoluble and no performance degradation under oxidative and reductive conditions), high mechanical strength (no dimensional change under system operating conditions), and other factors determined by the operating conditions of the electrochemical reaction. The porous matrix must be electrochemically cell-chemically compatible and meet the mechanical requirements of cell stacking or winding assembly operations.

[0141] Polymers suitable for preparing the porous matrix can be selected from, but are not limited to, polyolefins (such as polyethylene and polypropylene), polyamides (such as nylon 6 and nylon 6,6), polyesters, cellulose acetate, polybenzimidazole, fluorocarbon-based polymers (such as PTFE and PVDF), polycarbonates, cellulose, or combinations thereof. These polymers offer various properties such as low cost, high stability in alkaline water, good mechanical stability, and ease of processing for porous matrix fabrication.

[0142] The porous matrix can be a non-woven matrix or a woven matrix and has a symmetric porous structure or an asymmetric porous structure. The porous matrix can be formed by electrospinning, direct air drying after a phase inversion membrane manufacturing method, or by a solvent exchange method after phase inversion. The porous matrix can also be manufactured via dry processing of thermoplastic polyolefins or wet processing of thermoplastic olefins. Dry processing of thermoplastic polyolefins uses extrusion to heat the polymer above its melting point and form it into a desired shape. Subsequent annealing and stretching processes can also be carried out to increase the crystallinity, orientation, and size of the pores. Wet processing of polyolefin porous matrices is carried out by mixing a hydrocarbon liquid or a low molecular weight oil with a polymer resin or a mixture of a polymer resin and inorganic nanoparticles in the molten phase. The molten mixture is extruded through a die similar to the spacer used in dry processing. The thickness of the porous matrix can be in the range of 10 microns to 400 microns, or in the range of 10 microns to 200 microns, or in the range of 10 microns to 100 microns, or in the range of 20 microns to 100 microns. The pore size of the porous matrix can be in the range of 1 micron to 500 microns, or in the range of 10 microns to 200 microns, or in the range of 50 microns to 100 microns.

[0143] In some embodiments, a thin film composite anion exchange membrane is prepared using a method comprising the following steps: 1) dissolving an anion exchange polymer in a solvent to form a polymer coating solution; 2) coating a layer of the anion exchange polymer coating solution on one surface of a microporous support membrane via dip coating, meniscus coating, concave coating, comma knife coating, spin coating, casting, soaking, spraying, painting, or other known conventional solution coating techniques; 3) drying the coated membrane at 50°C to 150°C, or 50°C to 120°C, or 80°C to 120°C; and optionally, 4) replacing the acetate (CH3COO - )、trifluoroacetate (CF3COO - )、propionate (CH3CH2COO - ) or butyrate (CH3CH2CH2COO -) Anions are ion-exchanged with hydroxide anions to form a thin-film composite anion exchange membrane. Solvents for preparing the thin-film composite anion exchange membrane include, but are not limited to, NMP, DMAC, DMF, DMSO, dioxane, 1,3-dioxolane, and mixtures thereof. The microporous support membrane should have good thermal stability (stable at up to at least 120 °C), high stability under high pH conditions (e.g., pH greater than 8), high tolerance to oxidation and reduction conditions (insoluble and no performance degradation under oxidation and reduction conditions), high mechanical strength (no dimensional change under the operating conditions of the system), and other factors determined by the operating conditions of the electrochemical reaction. The microporous support membrane must be chemically compatible with the electrochemical cell and meet the mechanical requirements for cell stacking or winding assembly operations.

[0144] Polymers suitable for preparing the microporous support membrane can be selected from, but are not limited to, polyolefins (such as polyethylene and polypropylene), polyamides (such as nylon 6 and nylon 6,6), polyesters, cellulose acetate, polybenzimidazole, fluorocarbon-based polymers (such as PTFE and PVDF), polycarbonates, cellulose, or combinations thereof. These polymers offer various properties such as low cost, high stability in alkaline water, good mechanical stability, and ease of processing for membrane fabrication.

[0145] The microporous support membrane can have a symmetric porous structure or an asymmetric porous structure. The asymmetric microporous support membrane can be formed by direct air drying after a phase inversion membrane fabrication method or by a solvent exchange method after phase inversion. The microporous support membrane can also be fabricated by dry processing of thermoplastic polyolefins or wet processing of thermoplastic olefins. Dry processing of thermoplastic polyolefins uses extrusion to heat the polymer above its melting point and form it into a desired shape. Subsequent annealing and stretching processes can also be carried out to increase the crystallinity, orientation, and size of the micropores. Wet processing of polyolefin separators is carried out by mixing a hydrocarbon liquid or low molecular weight oil with a polymer resin or a mixture of a polymer resin and inorganic nanoparticles in the molten phase. The molten mixture is extruded through a die similar to that in the dry process for the separator. The thickness of the microporous support membrane can be in the range of 10 microns to 400 microns, or in the range of 10 microns to 200 microns, or in the range of 10 microns to 100 microns, or in the range of 20 microns to 100 microns. The pore size of the microporous membrane can be in the range of 10 nanometers to 50 microns, or in the range of 50 nanometers to 10 microns, or in the range of 0.2 microns to 1 micron.

[0146] Another aspect of the present invention is a membrane electrode assembly. In one embodiment, the membrane electrode assembly includes: an anion exchange membrane comprising the above polymer; a cathode comprising a cathode catalyst on a first surface of the anion exchange membrane; and optionally, an anode comprising an anode catalyst on a second surface of the anion exchange membrane.

[0147] In some embodiments, the membrane electrode assembly further includes: a cathode porous transport layer adjacent to the cathode; and an anode porous transport layer or an anode catalyst-coated anode porous transport layer adjacent to the anode. In some embodiments, the anode and cathode catalysts are platinum group metal (PGM)-free electrocatalysts. The anode and cathode catalysts are used for oxygen evolution reaction and hydrogen evolution reaction respectively. The anode and cathode catalysts should have low cost, good conductivity, and good electrocatalytic activity and stability. Suitable PGM-free cathode catalysts can be selected from but not limited to Ni-based alloys (such as Ni-Mo, Ni-Al, Ni-Cr, Ni-Sn, Ni-Co, Ni-W, and Ni-Al-Mo), metal carbides (such as Mo2C), metal phosphides (such as CoP), metal dichalcogenides (such as MoSe2), and mixtures thereof. Suitable anode catalysts can be selected from but not limited to Ni-Fe alloys, Ni-Mo alloys, spinel Cu x Co 3x CoO3, Ni-Fe layered double hydroxide nanosheets, immobilized metal catalysts on conductive supports, and mixtures thereof. In some embodiments, the anode and cathode catalysts are PGM electrocatalysts. Suitable PGM cathode catalysts can be selected from but not limited to platinum, ruthenium, osmium, rhodium, palladium, tin, tungsten, vanadium, cobalt, silver, gold, nickel, molybdenum, iron, copper, chromium, their alloys, their oxides, their carbides, their phosphides, or combinations thereof. Suitable PGM anode catalysts can be selected from but not limited to iridium, platinum, ruthenium, osmium, rhodium, palladium, tin, tungsten, vanadium, cobalt, silver, gold, copper, nickel, molybdenum, iron, chromium, their alloys, their oxides, their carbides, their phosphides, or combinations thereof.

[0148] In some embodiments, the cathode including the cathode catalyst on the first surface of the anion exchange membrane is formed by: coating the cathode catalyst ink on the first surface of the anion exchange membrane via meniscus coating, knife coating, spraying, painting, concave coating, comma knife coating, or other known conventional ink coating techniques, and then drying the coated anion exchange membrane.

[0149] In some embodiments, the anode including the anode catalyst on the second surface of the anion exchange membrane is formed by: coating the anode catalyst ink on the second surface of the anion exchange membrane via meniscus coating, knife coating, spraying, painting, concave coating, comma knife coating, or other known conventional ink coating techniques, and then drying the coated anion exchange membrane.

[0150] In some embodiments, the anode catalyst ink contains an anode catalyst and OH as a binder- Exchange the ionomer and the solvent. In some embodiments, the cathode catalyst ink comprises a cathode catalyst, OH as a binder - Exchange the ionomer and the solvent. OH - The OH exchange ionomer binder creates OH transport channels between the reaction sites within the membrane and the electrode, thus greatly improving the utilization of the electrocatalyst particles while reducing the internal resistance. OH - transport channels, thus greatly improving the utilization of the electrocatalyst particles while reducing the internal resistance. OH - The OH exchange ionomer binder may have a chemical structure similar to the above-mentioned anion exchange polymer, such that the binder will achieve low interfacial resistance and similar swelling upon contact with water to avoid catalyst delamination, but maintain OH - conductivity as well as high oxygen and hydrogen permeability. OH - The OH exchange ionomer binder may have a chemical structure similar to the above-mentioned anion exchange polymer, but with different counterions, such as bicarbonate (HCO3 - ) counterions. The solvent may be selected from but not limited to water, alcohols, or mixtures thereof.

[0151] The anode porous transport layer and the cathode porous transport layer transport electrons, heat, and products simultaneously with minimal voltage, current, heat, interface, and fluid losses. The cathode porous transport layer may be made of but not limited to stainless steel, titanium mesh, titanium felt, titanium foam, or carbon-based materials (such as non-woven carbon paper, non-woven carbon cloth, or woven carbon cloth). The anode porous transport layer may be made of but not limited to stainless steel, titanium mesh, titanium felt, or titanium foam.

[0152] Example

[0153] Example 1: Synthesis of poly(triphenylene-co-phenanthrenylene piperidinium acetate) (abbreviated as PTPP-OAc)

[0154] As Figure 3 shown, the poly(triphenylbenzene-co-phenanthrenepiperidinium iodide) (abbreviated as PTPP-I) polymer having iodide counterions as described in Example 2 of U.S. Patent Application No. 17 / 823,975 was converted to poly(triphenylbenzene-co-phenanthrenepiperidinium acetate) (abbreviated as PTPP-OAc) via an ion exchange reaction. 140 g of the PTPP-I anion exchange polymer was dispersed in 4 L of a 1.0 wt% potassium acetate or acetic acid aqueous solution and stirred at ambient temperature for 1 h. The mixture was filtered, and the filter cake was resuspended in 4 L of a 1.0 wt% potassium acetate or acetic acid aqueous solution to repeat the ion exchange filtration process. The ion exchange filtration step was repeated several times to completely exchange the iodide anions for acetate anions. The product was soaked in 4 L of reverse osmosis water with stirring for 1 h and filtered. The water soaking and filtration were repeated three times. Then the obtained filtered product was dried at 60 °C for at least 24 h to produce the PTPP-OAc anion exchange polymer.

[0155] Example 2: Synthesis of poly(triphenylene-co-phenanthrenylene piperidinium hydrogencarbonate) (abbreviated as PTPP-HCO3 - )

[0156] The poly(triphenylene-co-phenanthrenepiperidinium iodide) (abbreviated as PTPP-I) polymer having an iodide counterion as described in Example 2 of U.S. Patent Application No. 17 / 823,975 was converted to poly(triphenylene-co-phenanthrenepiperidinium hydrogencarbonate) (abbreviated as PTPP-HCO₃) via an ion exchange reaction. - ) 100 g of the PTPP-I anion exchange polymer was dispersed in 4 L of a 2.0 wt% aqueous sodium hydrogencarbonate solution and stirred at ambient temperature for 1 h. The mixture was filtered, and the filter cake was resuspended in 4 L of a 2.0 wt% aqueous sodium hydrogencarbonate solution to repeat the ion exchange filtration process. The ion exchange filtration step was repeated several times to completely exchange the iodide anions for hydrogencarbonate anions. The product was soaked in 4 L of reverse osmosis water with stirring for 1 h and filtered. The water soaking and filtration were repeated three times. Then the obtained filtered product was dried at 60 °C for at least 24 h to produce the PTPP-HCO₃ - polymer.

[0157] Example 3: Preparation of poly(triphenylene-co-phenanthrenylene piperidinium acetate) anion exchange polymer membrane (abbreviated as PTPP-OAc membrane)

[0158] The PTPP-OAc anion exchange polymer membrane was prepared by dissolving the PTPP-OAc anion exchange polymer (5.0 g) as described in Example 1 in DMSO (20 g), casting the solution on a clean substrate, and drying it overnight at 60 °C. The membrane was peeled off from the substrate and further dried in a vacuum oven at 100 °C for 48 h. The PTPP-OAc membrane was subjected to ion exchange in a 1 M aqueous KOH solution for 10 h to convert the PTPP-OAc anion exchange membrane having acetate anions to an anion exchange membrane having OH - anions (abbreviated as PAPP-OH membrane) to measure its in-plane hydroxide conductivity. The in-plane hydroxide conductivity of the PAPP-OH membrane was 126.8 mS / cm at room temperature.

[0159] Example 4: Preparation of a bilayer membrane electrode assembly (MEA) (abbreviated as Pt / PAPP-OAc MEA) comprising a PAPP-OAc anion exchange membrane and a cathode catalyst coating

[0160] The cathode catalyst ink was prepared by mixing a 40% Pt / C catalyst, the PAPP-HCO₃ - polymer as an ionomer prepared as in Example 2, in H₂O and ethanol. The mixture was finely dispersed using an ultrasonic bath. The cathode catalyst ink was coated onto one surface of the PAPP-OAc anion exchange membrane prepared as in Example 3 via a spraying or Mayer rod coating technique. The Pt loading was 0.15 mg / cm 2。

[0161] Comparative Example 1: Poly(triphenylene-co-phenanthrenylene piperidinium bicarbonate) anion exchange polymer membrane (abbreviated as PTPP-HCO3 - Preparation of (membrane)

[0162] By dissolving the PTPP-HCO3 - anion exchange polymer (5.0 g) as described in Example 2 in ethanol (30 g), casting the solution on a clean substrate, and drying it overnight at 50 °C to prepare the PTPP-HCO3 - anion exchange polymer membrane. The membrane was peeled off from the substrate and further dried in a vacuum oven at 100 °C for 48 h.

[0163] Comparative Example 2: Containing PTPP-HCO3 - Double-membrane electrode assembly of anion exchange membrane and cathode catalyst coating (MEA) (abbreviated as Pt / PTPP-HCO3 - Preparation of MEA

[0164] A cathode catalyst ink was prepared by mixing a 40% Pt / C catalyst in H2O and ethanol, and the PAPP-HCO3 - polymer prepared as an ionomer in Example 2. The mixture was finely dispersed using an ultrasonic bath. The cathode catalyst ink was coated onto one surface of the PTPP-HCO3 - anion exchange membrane prepared in Comparative Example 1 by spraying or Mayer rod coating techniques. The Pt loading was 0.15 mg / cm 2 。

[0165] Example 5: Preparation of an anodic catalyst-coated porous transport layer (abbreviated as IrO2 / PTL)

[0166] An anode catalyst ink was prepared by mixing the PGM anode catalyst IrO2 and the PAPP-HCO3 - ionomer prepared in Example 2 in H2O and ethanol. The mixture was finely dispersed using an ultrasonic bath. The IrO2 anode catalyst ink was sprayed onto one surface of a stainless steel porous transport layer to form an IrO2 anode catalyst-coated stainless steel porous transport layer (abbreviated as IrO2 / PTL). The IrO2 anode catalyst loading was 2.0 mg / cm 2 。

[0167] Example 6: Evaluation of the water electrolysis performance of (a) Pt / PAPP-OAc MEA and (b) Pt / PAPP-HCO3 - MEA

[0168] An anion exchange membrane (AEM) water electrolysis test station was used to evaluate (a) the Pt / PAPP-OAc 2-layer MEA prepared in Example 4 and (b) the Pt / PTPP-HCO3 - 2-layer MEA at 5 cm 2The water electrolysis performance in a single electrolytic cell with an active membrane area. The test station includes an integrated power supply, a voltage regulator, an impedance analyzer for electrochemical impedance spectroscopy (EIS) and high-frequency resistance (HFR), and real-time sensors for product flow rate and permeation monitoring. The Pt / PAPP-OAc 2-layer MEA or Pt / PTPP-HCO3 - The 2-layer MEA was sandwiched between carbon paper (as the cathode PTL) and IrO2 / PTL prepared as in Example 5. The test was carried out at 80 °C and at atmospheric pressure. Ultra-pure water was supplied to the anode side and the cathode side of the electrolytic cell at a flow rate of 100 mL / min. Polarization curves were collected at 80 °C, and the results are shown in Figure 4 From Figure 4 In the polarization curves in, it can be observed that at the same current density, especially at current densities above 200 mA / cm 2 The Pt / PAPP-OAc 2-layer MEA provides a lower cell voltage for the AEM water electrolyzer than the Pt / PTPP-HCO3 - 2-layer MEA, indicating that the AEM water electrolyzer containing the Pt / PAPP-OAc 2-layer MEA has higher efficiency than the electrolyzer containing the Pt / PTPP-HCO3 - 2-layer MEA.

[0169] Specific embodiments

[0170] Although the following is described in connection with specific embodiments, it should be understood that the description is intended to illustrate and not limit the scope of the foregoing description and the appended claims.

[0171] A first embodiment of the present invention is a composition comprising a plurality of repeating units of formula (I) wherein Ar1 is selected from the group consisting of:

[0172]

[0173] and mixtures thereof; X1 is selected from the group consisting of: Optionally and mixtures thereof; wherein Y1 - or Y2 - or both are wherein R1 to R 28 are each independently hydrogen, a halide, an alkyl group, an alkenyl group, an alkynyl group or an aryl group, and the alkyl group, alkenyl group, alkynyl group or aryl group is optionally substituted with a halide or a positively charged functional group; wherein R 29 to R 31Each is independently hydrogen, an alkyl group, an alkenyl group, an alkynyl group, or an aryl group, and the alkyl group, alkenyl group, alkynyl group, or aryl group is optionally substituted with a halide or a positively charged functional group; wherein R 32 is an alkyl group, an alkenyl group, an alkynyl group, or an aryl group, and the alkyl group, alkenyl group, alkynyl group, or aryl group is optionally substituted with a halide or a positively charged functional group; wherein R 50 is CH3, CF3, CH3CH2, or CH3CH2CH2; wherein A is O, S, or NR 100 ; wherein R 100 is hydrogen, an alkyl group, an alkenyl group, an alkynyl group, or an aryl group, and the alkyl group, alkenyl group, alkynyl group, or aryl group is optionally substituted with a halide or a positively charged functional group; wherein n is an integer from 10 to 1000; wherein p is 1, 2, 3, or 4; wherein q is 0, 1, 2, or 3; and wherein t is 1, 2, 3, 4, 5, or 6. Embodiments of the present invention are one, any, or all of the previous embodiments in this paragraph up to the first embodiment in this paragraph, wherein Ar1 is selected from the group consisting of:

[0174] and mixtures thereof; wherein R 25 , R 26 , R 27 and R 28 are each independently -H or -CH3; wherein p is 1 or 2; and wherein q is 0 or 1. Embodiments of the present invention are one, any, or all of the previous embodiments in this paragraph up to the first embodiment in this paragraph, wherein Ar1 is selected from

[0175]

[0176] and mixtures thereof. Embodiments of the present invention are the previous embodiments in this paragraph

[0177] up to one, any, or all of the first embodiments in this paragraph, wherein Ar1 is selected from the group consisting of:

[0178]

[0179] and mixtures thereof. Embodiments of the present invention are one, any, or all of the previous embodiments in this paragraph up to the first embodiment in this paragraph, wherein X1 is wherein R 30 and R 31Each is independently -H, -CH3, -CH2CH3, -CH(CH3)2, -C(CH3)3, -CH2-C6H5 or -CH2-CH(CH3)2, where Y1 - is and where R 50 is CH3, CF3, CH3CH2 or CH3CH2CH2. Embodiments of the present invention are one, any or all of the previous embodiments in this paragraph up to the first embodiment in this paragraph, where X1 is where t is 1, 2, 3, 4, 5 or 6, where Y2 - is and where R 50 is CH3, CF3, CH3CH2 or CH3CH2CH2. Embodiments of the present invention are one, any or all of the previous embodiments in this paragraph up to the first embodiment in this paragraph, where X1 is a mixture of, where R 30 and R 31 are each independently -H, -CH3, -CH2CH3, -CH(CH3)2, -C(CH3)3, -CH2-C6H5 or -CH2-CH(CH3)2; where t is 1, 2, 3, 4, 5 or 6; where Y1 - and Y2 - are and where R 50 is CH3, CF3, CH3CH2 or CH3CH2CH2. Embodiments of the present invention are one, any or all of the previous embodiments in this paragraph up to the first embodiment in this paragraph, where the anion exchange polymer is synthesized from monomers Ar1' and X1', where Ar1' is selected from the group consisting of

[0180]

[0181] and mixtures thereof; and X1' is selected from the group consisting of optionally and mixtures thereof; where Y2 - is where R 50 is CH3, CF3, CH3CH2 or CH3CH2CH2; where R1 to R 28 are each independently hydrogen, halide, alkyl group, alkenyl group, alkynyl group or aryl group, and the alkyl group, alkenyl group, alkynyl group or aryl group is optionally substituted with a halide or a positively charged functional group; where R 29 and R 30each independently is hydrogen, an alkyl group, an alkenyl group, an alkynyl group or an aryl group, and the alkyl group, alkenyl group, alkynyl group or aryl group is optionally substituted by a halide or a positively charged functional group; wherein R 32 is an alkyl group, an alkenyl group, an alkynyl group or an aryl group, and the alkyl group, alkenyl group, alkynyl group or aryl group is optionally substituted by a halide or a positively charged functional group; wherein A is O, S or NR 100 ; wherein R 100 is hydrogen, an alkyl group, an alkenyl group, an alkynyl group or an aryl group, and the alkyl group, alkenyl group, alkynyl group or aryl group is optionally substituted by a halide or a positively charged functional group; wherein p is 1, 2, 3 or 4; wherein q is 0, 1, 2 or 3; and wherein t is 1, 2, 3, 4, 5 or 6. Embodiments of the present invention are one, any or all of the previous embodiments in this paragraph up to the first embodiment in this paragraph, wherein Ar1' is selected from the group consisting of and mixtures thereof; wherein R 25 , R 26 , R 27 and R 28 are each independently -H or -CH3; wherein p is 1 or 2; and wherein q is 0 or 1. Embodiments of the present invention are one, any or all of the previous embodiments in this paragraph up to the first embodiment in this paragraph, wherein Ar1' is selected from the group consisting of and mixtures thereof. Embodiments of the present invention are one, any or all of the previous embodiments in this paragraph up to the first embodiment in this paragraph, wherein Ar1' is selected from the group consisting of and mixtures thereof. Embodiments of the present invention are one, any or all of the previous embodiments in this paragraph up to the first embodiment in this paragraph, wherein X1' is and wherein R 30 is -H, -CH3, -CH2CH3, -CH(CH3)2, -C(CH3)3, -CH2-C6H5 or -CH2-CH(CH3)2. Embodiments of the present invention are one, any or all of the previous embodiments in this paragraph up to the first embodiment in this paragraph, wherein X1 is wherein t is 1, 2, 3, 4, 5 or 6, wherein Y2 - is wherein R 50is CH3, CF3, CH3CH2 or CH3CH2CH2. Embodiments of the present invention are one, any or all of the previous embodiments in this paragraph up to the first embodiment in this paragraph, where X1’ is a mixture of the composition, and where t is 1, 2, 3, 4, 5 or 6, where Y2 - is and where R 50 is CH3, CF3, CH3CH2 or CH3CH2CH2. A system comprising the anion exchange polymer. Embodiments of the present invention are one, any or all of the previous embodiments in this paragraph up to the first embodiment in this paragraph, where the anion exchange membrane is used in a fuel cell, an electrolyzer, a flow battery, an electrodialyzer, a waste metal recovery system, an electrocatalytic hydrogen production system, a desalination device, a water purifier, a wastewater treatment system, an ion exchanger or a CO2 separator. Embodiments of the present invention are one, any or all of the previous embodiments in this paragraph up to the first embodiment in this paragraph, where the anion exchange membrane comprises a non-porous symmetric dense membrane, a dense skin asymmetric membrane, a reinforced composite membrane or a thin film composite membrane. Embodiments of the present invention are one, any or all of the previous embodiments in this paragraph up to the first embodiment in this paragraph, where the dense skin asymmetric membrane, the reinforced composite membrane or the thin film composite membrane comprises a porous substrate material impregnated or coated with the anion exchange polymer.

[0182] A second embodiment of the present invention is a membrane electrode assembly, the membrane electrode assembly comprising an anion exchange membrane, the anion exchange membrane comprising the anion exchange polymer; a cathode, the cathode comprising a cathode catalyst on a first surface of the anion exchange membrane; and optionally, an anode, the anode comprising an anode catalyst on a second surface of the anion exchange membrane. Embodiments of the present invention are one, any or all of the previous embodiments in this paragraph up to the second embodiment in this paragraph, where the assembly further comprises: a cathode porous transport layer adjacent to the cathode; and an anode porous transport layer or an anode porous transport layer coated with an anode catalyst, the anode porous transport layer or the anode porous transport layer coated with an anode catalyst adjacent to the anode.

[0183] Although no further elaboration is provided, it is believed that those skilled in the art can make the most of the present invention by using the foregoing description and can readily determine the basic features of the present invention without departing from the essence and scope of the present invention to make various changes and modifications thereto and adapt it to various uses and conditions. Therefore, the foregoing preferred specific embodiments should be construed as illustrative only and not in any way limiting the remainder of the disclosure, and are intended to cover various modifications and equivalent arrangements included within the scope of the appended claims.

[0184] In the foregoing, all temperatures are shown in degrees Celsius and all parts and percentages are by weight unless otherwise indicated.

Claims

1. An anion exchange polymer, the anion exchange polymer comprising a plurality of repeating units of formula (I) wherein Ar1 is selected from the group consisting of: and mixtures thereof; X1 is selected from the group consisting of: Optionally and mixtures thereof; where Y1 - or Y2 - or both are wherein R1 to R 28 are each independently hydrogen, a halide, an alkyl group, an alkenyl group, an alkynyl group or an aryl group, and the alkyl group, alkenyl group, alkynyl group or aryl group is optionally substituted by a halide or a positively charged functional group; wherein R 29 to R 31 are each independently hydrogen, an alkyl group, an alkenyl group, an alkynyl group or an aryl group, and the alkyl group, alkenyl group, alkynyl group or aryl group is optionally substituted by a halide or a positively charged functional group; wherein R 32 is an alkyl group, an alkenyl group, an alkynyl group or an aryl group, and the alkyl group, alkenyl group, alkynyl group or aryl group is optionally substituted by a halide or a positively charged functional group; wherein R 50 is CH3, CF3, CH3CH2 or CH3CH2CH2; wherein A is O, S or NR 100 ; wherein R 100 is hydrogen, an alkyl group, an alkenyl group, an alkynyl group or an aryl group, and the alkyl group, alkenyl group, alkynyl group or aryl group is optionally substituted by a halide or a positively charged functional group; where n is an integer from 10 to 1000; where p is 1, 2, 3 or 4; where q is 0, 1, 2 or 3; and where t is 1, 2, 3, 4, 5 or 6.

2. The anion exchange polymer according to claim 1, wherein Ar1 is selected from the group consisting of: and mixtures thereof; wherein R 25 , R 26 , R 27 and R 28 are each independently -H or -CH3; where p is 1 or 2; and where q is 0 or 1.

3. The anion exchange polymer according to claim 1, wherein Ar1 is selected from the group consisting of: and mixtures thereof.

4. The anion exchange polymer according to claim 1, wherein Ar1 is selected from the group consisting of: and mixtures thereof.

5. The anion exchange polymer according to claim 1, wherein X1 is wherein R 30 and R 31 are each independently -H, -CH3, -CH2CH3, -CH(CH3)2, -C(CH3)3, -CH2-C6H5 or -CH2-CH(CH3)2, where Y1 - is and wherein R 50 is CH3, CF3, CH3CH2 or CH3CH2CH2.

6. The anion exchange polymer according to claim 1, wherein X1 is where t is 1, 2, 3, 4, 5 or 6, Among them, Y2 - is and wherein R 50 is CH3, CF3, CH3CH2 or CH3CH2CH2.

7. The anion exchange polymer according to claim 1, wherein X1 is a mixture of the following wherein R 30 and R 31 are each independently -H, -CH3, -CH2CH3, -CH(CH3)2, -C(CH3)3, -CH2-C6H5 or -CH2-CH(CH3)2; where t is 1, 2, 3, 4, 5 or 6; where Y1 - and Y2 - are and wherein R 50 is CH3, CF3, CH3CH2 or CH3CH2CH2.

8. The anion exchange polymer according to claim 1, wherein the anion exchange polymer is synthesized from monomers Ar1' and X1', where Ar1' is selected from the group consisting of: and mixtures thereof; and X1' is selected from the group consisting of: Optionally and mixtures thereof; Among which Y2 - is wherein R 50 is CH3, CF3, CH3CH2 or CH3CH2CH2; wherein R1 to R 28 are each independently hydrogen, a halide, an alkyl group, an alkenyl group, an alkynyl group or an aryl group, and the alkyl group, alkenyl group, alkynyl group or aryl group is optionally substituted by a halide or a positively charged functional group; wherein R 29 and R 30 are each independently hydrogen, an alkyl group, an alkenyl group, an alkynyl group or an aryl group, and the alkyl group, alkenyl group, alkynyl group or aryl group is optionally substituted with a halide or a positively charged functional group; wherein R 32 is an alkyl group, an alkenyl group, an alkynyl group or an aryl group, and the alkyl group, alkenyl group, alkynyl group or aryl group is optionally substituted by a halide or a positively charged functional group; where A is O, S or NR 100 ; wherein R 100 is hydrogen, an alkyl group, an alkenyl group, an alkynyl group or an aryl group, and the alkyl group, alkenyl group, alkynyl group or aryl group is optionally substituted with a halide or a positively charged functional group; where p is 1, 2, 3 or 4; where q is 0, 1, 2 or 3; and where t is 1, 2, 3, 4, 5 or 6.

9. An anion exchange membrane, the anion exchange membrane comprising the anion exchange polymer according to claim 1.

10. A membrane electrode assembly, the membrane electrode assembly comprising: an anion exchange membrane, the anion exchange membrane comprising the anion exchange polymer according to claim 1; a cathode, the cathode comprising a cathode catalyst on a first surface of the anion exchange membrane; optionally, an anode, the anode comprising an anode catalyst on a second surface of the anion exchange membrane. optionally, a cathode porous transport layer adjacent to the cathode; and optionally, an anode porous transport layer or an anode catalyst-coated anode porous transport layer adjacent to the anode.

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