Norbornene-containing bis-benzocyclobutane polyaryl piperidine anion exchange membrane material as well as preparation method and application thereof

Abstract

The invention discloses an anion exchange membrane material containing norbornene dibenzocyclobutane polyaryl piperidine as well as a preparation method and application of the anion exchange membrane material, and relates to the field of anion exchange membrane materials for hydrogen production by electrolysis of water. According to the invention, norbornene bis-benzocyclobutane is introduced into a polymer main chain of aromatic hydrocarbon and piperidone to form a distorted and difficult-to-rotate space structure. By adopting the technical scheme, the structural rigidity and larger free volume of a polymer skeleton are improved, the formation of a large number of microporous structures is promoted, the agglomeration of ion clusters is facilitated, more phase separation structures are formed, and the ionic conductivity of the membrane material is improved through the synergistic effect of the two, so that the membrane material is more stable in performance. And meanwhile, the problem of relatively poor dimensional stability caused by excessive water absorption of the membrane material is inhibited, and the prepared anion exchange membrane has a wide application prospect in the field of hydrogen production by water electrolysis.

Description

Technical Field

[0001] This invention belongs to the technical field of water electrolysis and ion exchange membrane materials, specifically relating to a norbornene-containing dibenzocyclobutane-based polyarylpiperidine anion exchange membrane material, its preparation method, and its application. Background Technology

[0002] With the advancement of global "dual-carbon" goals, hydrogen energy, as a secondary energy source that is abundant, green, low-carbon, and widely applicable, is being regarded as a key carrier for building a future clean energy system. However, currently, over 95% of the world's hydrogen is produced from fossil fuel reforming or industrial by-products (collectively referred to as "gray hydrogen" and "blue hydrogen"), a process accompanied by substantial carbon dioxide emissions, which contradicts the original intention of developing hydrogen energy. Therefore, utilizing renewable energy to drive water electrolysis to produce "green hydrogen" has become the fundamental path to achieving the sustainable development of the hydrogen energy industry. Although using intermittent renewable energy sources such as wind and solar power to electrolyze water for hydrogen production is an ideal "green hydrogen" preparation scheme, its large-scale commercialization still faces bottlenecks in the economics and efficiency of core technologies. Among existing water electrolysis hydrogen production technologies, alkaline water electrolysis (AWE) has a long equipment life and low cost, but its current density is limited and its start-up and shutdown response is slow. Proton exchange membrane water electrolysis (PEMWE) has a fast dynamic response and high efficiency, but it relies on precious metal catalysts and perfluorosulfonic acid membranes, resulting in high equipment costs. Solid oxide water electrolysis (SOE) has the best theoretical efficiency, but its operating temperature is as high as 700-900℃, posing serious challenges to system stability and material durability. Anion exchange membrane water electrolysis (AEMWE), as an emerging technology, combines the advantages of using non-precious metal catalysts in alkaline environments and the compact structure of polymer membranes, and is recognized by the industry as the next-generation water electrolysis technology with the greatest potential for cost breakthrough.

[0003] Compared to traditional proton exchange membrane electrolyzers, AEM electrolyzers can utilize inexpensive metal catalysts such as nickel, iron, and cobalt under weakly alkaline conditions, eliminating reliance on precious metals like platinum and iridium and significantly reducing system costs. Simultaneously, AEM technology retains the advantages of PEM technology, such as compact structure and flexible operation, providing an ideal solution for distributed hydrogen production and the consumption of fluctuating renewable energy. However, to achieve large-scale commercial application of AEM technology, three major technical bottlenecks in anion exchange membrane materials still need to be overcome: First, the OH content of existing anion exchange membranes... - The ion conductivity is generally lower than that of proton exchange membranes, making it difficult to further improve electrolysis efficiency. Secondly, under strongly alkaline and high-temperature (>60℃) operating environments, the functional cationic groups (such as quaternary ammonium groups, imidazolium groups, etc.) of the membrane material are easily affected by OH groups. -Chemical degradation due to nucleophilic attack by ions leads to a continuous decline in ionic conductivity. Finally, traditional linear polymer anion exchange membranes generally have high water absorption rates; excessive hydration and swelling not only reduce the dimensional stability of the membrane but also affect the assembly accuracy and long-term operational reliability of the electrolyzer. Therefore, the design of the polymer backbone structure is crucial to improving the alkali resistance and service life of anion exchange membranes. An article in the journal *Polymer*, Volume 320, 2025 (DOI: 10.1016 / j.polymer.2025.128117), reported on anion exchange membranes prepared by superacid polymerization of bromospirobisfluorene monomers, terphenyl, and N-methyl-4-piperidinone to increase the free volume between polymer chains, thereby improving ionic conductivity. However, the water absorption and swelling rate of the membrane did not decrease, thus dimensional stability was not maintained. Chinese invention patent CN 117843933 A discloses a high free volume polyarylpiperidine copolymer and anion exchange membrane. This polymer structure incorporates a class of high free volume phenyl monomers (such as 2,2'-dibromo-9,9'-spirodifluorene), resulting in a larger free volume in the polymer backbone, which is beneficial for ion cluster aggregation and conduction. In the 2,2'-dibromo-9,9'-spirodifluorene monomer, two bromine atoms replace hydrogen atoms at the reaction sites of the superacid-catalyzed polymerization in the 9,9'-spirodifluorene monomer. After replacement, these reaction sites no longer participate in the reaction. Superacid polymerization exposes the original benzene ring structure from the polymer backbone, providing a larger free volume. This invention improves the free volume and microphase separation structure of the polymer, thereby increasing the membrane's conductivity. However, the anion exchange membrane provided in this invention suffers from the same technical problem as the anion exchange membranes in the aforementioned technology: although it can improve ionic conductivity, the high water absorption and swelling rate of the membrane makes it impossible to guarantee its dimensional stability during use.

[0004] To address the technical problems existing in the prior art, this invention provides a norbornene-containing bisbenzocyclobutane-based polyarylpiperidine anion exchange membrane material, its preparation method, and its application, which improves the electrical conductivity of the material while reducing the ionic conductivity and enhancing dimensional stability during use. Summary of the Invention

[0005] To address the shortcomings of the aforementioned anion exchange membranes, this invention provides a norbornene-containing bisbenzocyclobutane-based polyarylpiperidine anion exchange membrane material, its preparation method, and its application.

[0006] To achieve the above-mentioned objectives, the present invention adopts the following technical solution: The present invention provides a norbornene bisbenzocyclobutane-based polyarylpiperidine anion exchange membrane, comprising norbornene bisbenzocyclobutane-based polymer backbones introduced into aromatic hydrocarbons and piperidinones to form a twisted and difficult-to-rotate spatial structure.

[0007] In a preferred embodiment, the norbornene-containing bisbenzocyclobutane-based polyarylpiperidine anion exchange membrane has the general structural formula shown in formula (I): Equation (I) Wherein, x is the molar percentage of norbornene-containing bisbenzocyclobutane units in the polymer, y is the molar percentage of linear structural units in the polymer, x is 1~50, y is 50~99, and x:y = (1~50):(99~50); Ar1 ​​is a norbornene-containing bisbenzocyclobutane monomer, and Ar2 is a linear phenyl monomer.

[0008] As a preferred embodiment, the protonated norbornene-containing bisbenzocyclobutane monomer comprises any one of the following structural formulas: .

[0009] The structures (a)-(c) above are respectively: (a) is 1,9-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl; (b) is 1,9-difluoro-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-difluoro-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl; (c) is 1,9-dichloro-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-dichloro-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl.

[0010] In a preferred embodiment, the linear phenyl monomer has any one of the following structures:

[0011] Among them, (a) is biphenyl, (b) is terphenyl, and (c) is tetraphenyl.

[0012] The method for preparing norbornene bisbenzocyclobutane monomers according to any one of the methods is characterized by comprising the following steps: 2-Bromotoluene, 2,5-norbornadiene, palladium acetate, triphenylphosphine, and cesium carbonate were mixed and then added to dioxane and stirred until homogeneous. The mixture was heated to 120-180°C until the reaction was complete. After cooling to room temperature, the mixture was purified to obtain a white solid powder, which is the norbornene bisbenzocyclobutane monomer (a) of 1,9-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl. 2-Fluorobromobenzene, 2,5-norbornadiene, palladium acetate, triphenylphosphine, and cesium carbonate were mixed and then dioxane was added and stirred until homogeneous. The mixture was heated to 120-180°C until the reaction was complete. After cooling to room temperature, the mixture was purified to obtain a white solid powder, which is the norbornene bisbenzocyclobutane monomer (b) of which is 1,9-difluoro-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-difluoro-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl. 2-Chlorobromobenzene, 2,5-norbornadiene, palladium acetate, triphenylphosphine, and cesium carbonate were mixed and then added to dioxane and stirred until homogeneous. The mixture was heated to 120-180°C until the reaction was complete. After cooling to room temperature, the mixture was purified to obtain a white solid powder, which is the norbornene bisbenzocyclobutane monomer (c) of which is 1,9-dichloro-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-dichloro-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl.

[0013] Exemplarily, the present invention provides a specific example of a method for preparing the above-mentioned norbornene bisbenzocyclobutane monomer (a), the specific steps of which include: adding 2-bromotoluene (3.4206 g, 20 mmol), 2,5-norbornadiene (0.9214 g, 10 mmol), palladium acetate (0.0449 g, 0.2 mmol), triphenylphosphine (0.1049 g, 0.4 mmol) and cesium carbonate (6.5164 g, 20 mmol) into a 350 mL pressure-resistant bottle, and then adding 100 mL of dioxane and stirring until homogeneous. The reaction was carried out at 150°C for 72 hours. After cooling to room temperature, the mixture was extracted with dichloromethane, filtered, rotary evaporated, and purified by column chromatography (developing solvent: pure petroleum ether) to obtain a white solid powder (a mixture of isomers of 1,9-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl), with a yield of 43%.

[0014] As a second aspect of the invention, the present invention also provides a method for preparing the norbornene-containing bisbenzocyclobutane-based polyarylpiperidine anion exchange membrane as described above, comprising: reacting a protonated norbornene-containing bisbenzocyclobutane-based polyarylpiperidine polymer with iodomethane to obtain the norbornene-containing bisbenzocyclobutane-based polyarylpiperidine polymer shown in formula (I).

[0015] As a preferred embodiment, the preparation method of the norbornene-containing bisbenzocyclobutane-based polyarylpiperidine anion exchange membrane includes: dissolving the protonated norbornene-containing bisbenzocyclobutane-based polyarylpiperidine polymer in a first organic solvent at 50°C, then adding iodomethane to react, then precipitating the reaction product in a second organic solvent, filtering and drying it, then dissolving it again in a third organic solvent, uniformly coating it on a substrate and drying it, and after ion exchange, obtaining the norbornene-containing bisbenzocyclobutane-based polyarylpiperidine anion exchange membrane shown in formula (I).

[0016] In a preferred embodiment, the reaction temperature is 50°C and the reaction time is 48–72 hours.

[0017] Preferably, the first organic solvent is at least one of dimethyl sulfoxide, N-methylpyrrolidone, N,N-dimethylformamide, and N,N-dimethylacetamide.

[0018] Preferably, the amount of the first organic solvent is 50 to 100 times the mass of the protonated norbornene-containing bisbenzocyclobutane polyarylpiperidine polymer.

[0019] Preferably, the second organic solvent is at least one selected from ethyl acetate, methanol, ethanol, acetone, and diethyl ether.

[0020] Preferably, the amount of the second organic solvent is 10 to 20 times the volume of the first organic solvent.

[0021] Preferably, the third organic solvent is at least one selected from dimethyl sulfoxide, N-methylpyrrolidone, N,N-dimethylformamide, and N,N-dimethylacetamide.

[0022] Preferably, the amount of the third organic solvent is 30 to 40 times the mass of the norbornene-containing dibenzocyclobutane-based polyarylpiperidine anion exchange membrane material.

[0023] The present invention also provides a protonated norbornene bisbenzocyclobutane polyarylpiperidine anionic polymer as described above, the structural formula of which is shown in formula (II): Formula (II); Wherein, x is the molar percentage of norbornene-containing bisbenzocyclobutane units in the polymer, y is the molar percentage of linear structural units in the polymer, x is 1~50, y is 50~99, and x:y = (1~50):(99~50); Ar1 ​​is a norbornene-containing bisbenzocyclobutane monomer, and Ar2 is a linear phenyl monomer.

[0024] Furthermore, the present invention also provides a method for preparing the protonated norbornene bisbenzocyclobutane polyarylpiperidine anionic polymer as described above, comprising the following steps: under a nitrogen atmosphere and an ice-water bath, adding a norbornene bisbenzocyclobutane monomer, a linear phenyl monomer, and N-methyl-4-piperidinone to a reaction vessel, then adding a fourth organic solvent, stirring, and then adding trifluoroacetic acid (TFA) and trifluoromethanesulfonic acid (TFSA) dropwise to the solution, reacting for 6-12 hours, pouring the resulting viscous solution into a fifth organic solvent, precipitating a white polymer precipitate, then washing with deionized water until the pH value is neutral, and drying in a vacuum oven at 80°C for 12-24 hours to obtain the polymer.

[0025] In a preferred embodiment, the molar ratio of the norbornene-containing bisbenzocyclobutane monomer and the linear phenyl monomer is (1~50):(99~50).

[0026] Preferably, the molar ratio of the linear phenyl monomer and N-methyl-4-piperidinone is 1:(1~1.5).

[0027] Preferably, the molar ratio of trifluoroacetic acid and N-methyl-4-piperidinone is (1~2):1.

[0028] Preferably, the molar ratio of trifluoromethanesulfonic acid to N-methyl-4-piperidinone is (8~12):1.

[0029] Preferably, the fourth organic solvent is any one of dichloromethane, chloroform, or tetrahydrofuran.

[0030] Preferably, the amount of the fourth organic solvent is 8 to 10 times the amount of N-methyl-4-piperidinone.

[0031] Preferably, the fifth organic solvent is any one of ethyl acetate, methanol, ethanol, diethyl ether, tetrahydrofuran, and acetone.

[0032] Preferably, the amount of the fifth organic solvent is 40 to 50 times the volume of the fourth organic solvent.

[0033] As a third aspect of the invention, the present invention also provides the application of the norbornene-containing bisbenzocyclobutane-based polyarylpiperidine anion exchange membrane material as described above in an alkaline water electrolyzer.

[0034] As a fourth aspect of the invention, the present invention also provides an alkaline water electrolyzer, including an electrolyte membrane, said electrolyte membrane comprising the norbornene-containing bisbenzocyclobutane-based polyarylpiperidine anion exchange membrane material as described above.

[0035] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) The present invention uses polyarylepiperidine polymer as the main chain, which can effectively improve the chemical stability of the membrane material; then, norbornene bisbenzocyclobutane monomers are introduced to improve the structural rigidity of the polymer skeleton, thereby promoting ion cluster aggregation and increasing phase separation. At the same time, the large-volume twisted structure also increases the free volume of the polymer chain, promotes the formation of a large number of micropores, effectively improves the ion conductivity of the membrane material, and also suppresses the problem of poor dimensional stability caused by excessive water absorption of the membrane material. The prepared anion exchange membrane has broad application prospects in the field of water electrolysis for hydrogen production.

[0036] (2) The norbornene-containing dibenzocyclobutane polyarylpiperidine polymer provided by the present invention is prepared by superacid-catalyzed Friedel-Crafts reaction. It can be directly used to prepare anion exchange membranes by casting. The prepared anion exchange membranes have good ionic conductivity, dimensional stability and chemical stability, and have good application prospects in the field of hydrogen production in alkaline water electrolyzers. Attached Figure Description

[0037] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0038] Figure 1 The 1H NMR spectrum of the monomer 1,9-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl provided in Example 1 of this invention.

[0039] Figure 2 This is a synthetic route diagram of the norbornene-containing bisbenzocyclobutane-based polyarylpiperidine anion exchange membrane material provided in Example 1 of the present invention.

[0040] Figure 3 The above are the 1H NMR spectra of the norbornene-containing bisbenzocyclobutane-based polyarylpiperidine anion exchange membrane materials described in Example 4 and Comparative Example 1 of this invention.

[0041] Figure 4 The OH groups of the norbornene-containing bisbenzocyclobutane-based polyarylpiperidine anion exchange membrane materials provided in Examples 1-5 and Comparative Example 1 of this invention are OH groups. - Ion conductivity diagram.

[0042] Figure 5 The CO2 adsorption-desorption curves are shown for the norbornene-containing bisbenzocyclobutane-based polyarylpiperidine anion exchange membrane materials provided in Examples 1 to 5 and Comparative Example 1 of this invention.

[0043] Figures 6a-6f The images are TEM images of the norbornene-containing bisbenzocyclobutane-based polyarylpiperidine anion exchange membrane materials provided in Comparative Example 1 and Examples 1 to 5 of the present invention. Detailed Implementation

[0044] The invention will be more fully understood through the following detailed description, which should be read in conjunction with the accompanying drawings. Detailed embodiments of the invention are disclosed herein; however, it should be understood that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. Therefore, the specific functional details disclosed herein should not be construed as limiting, but rather as the basis for the claims and as intended to teach those skilled in the art to employ the representative basis of the invention in different ways in any suitable detailed embodiment.

[0045] The present invention provides a norbornene-bisbenzocyclobutane-based polyarylpiperidine anion exchange membrane material having a structure of Formula 1; in Formula 1, x is the molar percentage of the norbornene-bisbenzocyclobutane-based unit in the polymer, y is the molar percentage of the linear structural unit in the polymer, x is 1~50, y is 50~99, and x:y = (1~50):(99~50).

[0046] Formula 1

[0047] Ar1 is a bisbenzocyclobutane monomer containing norbornene, and Ar2 is a linear phenyl monomer; The norbornene-containing dibenzocyclobutane monomer is:

[0048] Wherein, (a) is 1,9-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl, and (b) is 1,9-difluoro-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-difluoro-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl, and (b) is 1,9-difluoro-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-difluoro-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl. (b) Biphenyl, (c) is 1,9-dichloro-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-dichloro-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl; The method for preparing norbornene bisbenzocyclobutane monomers according to any one of the methods is characterized by comprising the following steps: 2-Bromotoluene, 2,5-norbornadiene, palladium acetate, triphenylphosphine, and cesium carbonate were mixed and then added to dioxane and stirred until homogeneous. The mixture was heated to 120-180°C until the reaction was complete. After cooling to room temperature, the mixture was purified to obtain a white solid powder, which is the norbornene bisbenzocyclobutane monomer (a) of 1,9-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl. 2-Fluorobromobenzene, 2,5-norbornadiene, palladium acetate, triphenylphosphine, and cesium carbonate were mixed and then dioxane was added and stirred until homogeneous. The mixture was heated to 120-180°C until the reaction was complete. After cooling to room temperature, the mixture was purified to obtain a white solid powder, which is the norbornene bisbenzocyclobutane monomer (b) of which is 1,9-difluoro-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-difluoro-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl. 2-Chlorobromobenzene, 2,5-norbornadiene, palladium acetate, triphenylphosphine, and cesium carbonate were mixed and then added to dioxane and stirred until homogeneous. The mixture was heated to 120-180°C until the reaction was complete. After cooling to room temperature, the mixture was purified to obtain a white solid powder, which is the norbornene bisbenzocyclobutane monomer (c) of which is 1,9-dichloro-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-dichloro-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl.

[0049] Exemplarily, the present invention provides a specific example of a method for preparing the above-mentioned norbornene bisbenzocyclobutane monomer (a), the specific steps of which include: adding 2-bromotoluene (3.4206 g, 20 mmol), 2,5-norbornadiene (0.9214 g, 10 mmol), palladium acetate (0.0449 g, 0.2 mmol), triphenylphosphine (0.1049 g, 0.4 mmol) and cesium carbonate (6.5164 g, 20 mmol) into a 350 mL pressure-resistant bottle, and then adding 100 mL of dioxane and stirring until homogeneous. The reaction was carried out at 150°C for 72 hours. After cooling to room temperature, the mixture was extracted with dichloromethane, filtered, rotary evaporated, and purified by column chromatography (developing solvent: pure petroleum ether) to obtain a white solid powder (a mixture of isomers of 1,9-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl), with a yield of 43%.

[0050] The linear phenyl monomers are:

[0051] Among them, (a) is biphenyl, (b) is terphenyl, and (c) is tetraphenyl.

[0052] As one of the objectives of the invention, the present invention also provides a method for preparing a norbornene-bisbenzocyclobutane-based polyarylpiperidine anion exchange membrane material, comprising: reacting the protonated trifluoroacetic acid-containing norbornene-bisbenzocyclobutane-based polyarylpiperidine polymer shown in Formula 2 with iodomethane (CH3I) to obtain the norbornene-bisbenzocyclobutane-based polyarylpiperidine anion exchange membrane material shown in Formula 1.

[0053] The protonated norbornene-containing bisbenzocyclobutane polyarylpiperidine polymer has the structural formula shown in Formula 2: Equation 2 Where x is the molar percentage of norbornene-containing bisbenzocyclobutane units in the polymer, y is the molar percentage of linear structural units in the polymer, x is 1~50, y is 50~99, and x:y = (1~50): (99~50).

[0054] Ar1 is a bisbenzocyclobutane monomer containing norbornene, and Ar2 is a linear phenyl monomer.

[0055] The norbornene-containing bisbenzocyclobutane monomer has any one of the following structures: , Wherein, (a) is 1,9-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl, and (b) is 1,9-difluoro-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-difluoro-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl, and (b) is 1,9-difluoro-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-difluoro-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl. (b) Biphenyl, (c) is 1,9-dichloro-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-dichloro-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl; The method for preparing norbornene bisbenzocyclobutane monomers according to any one of the methods is characterized by comprising the following steps: 2-Bromotoluene, 2,5-norbornadiene, palladium acetate, triphenylphosphine, and cesium carbonate were mixed and then added to dioxane and stirred until homogeneous. The mixture was heated to 120-180°C until the reaction was complete. After cooling to room temperature, the mixture was purified to obtain a white solid powder, which is the norbornene bisbenzocyclobutane monomer (a) of 1,9-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl. 2-Fluorobromobenzene, 2,5-norbornadiene, palladium acetate, triphenylphosphine, and cesium carbonate were mixed and then dioxane was added and stirred until homogeneous. The mixture was heated to 120-180°C until the reaction was complete. After cooling to room temperature, the mixture was purified to obtain a white solid powder, which is the norbornene bisbenzocyclobutane monomer (b) of which is 1,9-difluoro-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-difluoro-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl. 2-Chlorobromobenzene, 2,5-norbornadiene, palladium acetate, triphenylphosphine, and cesium carbonate were mixed and then added to dioxane and stirred until homogeneous. The mixture was heated to 120-180°C until the reaction was complete. After cooling to room temperature, the mixture was purified to obtain a white solid powder, which is the norbornene bisbenzocyclobutane monomer (c) of which is 1,9-dichloro-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-dichloro-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl.

[0056] Exemplarily, the present invention provides a specific example of a method for preparing the above-mentioned norbornene bisbenzocyclobutane monomer (a), the specific steps of which include: adding 2-bromotoluene (3.4206 g, 20 mmol), 2,5-norbornadiene (0.9214 g, 10 mmol), palladium acetate (0.0449 g, 0.2 mmol), triphenylphosphine (0.1049 g, 0.4 mmol) and cesium carbonate (6.5164 g, 20 mmol) into a 350 mL pressure-resistant bottle, and then adding 100 mL of dioxane and stirring until homogeneous. The reaction was carried out at 150°C for 72 hours. After cooling to room temperature, the mixture was extracted with dichloromethane, filtered, rotary evaporated, and purified by column chromatography (developing solvent: pure petroleum ether) to obtain a white solid powder (a mixture of isomers of 1,9-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl), with a yield of 43%.

[0057] The linear phenyl monomers mentioned are any one of the following structures:

[0058] Among them, (a) is biphenyl, (b) is terphenyl, and (c) is tetraphenyl.

[0059] Preferably, the preparation method includes: dissolving a protonated norbornene-containing bisbenzocyclobutane-based polyarylpiperidine polymer in a first organic solvent at 50°C, then adding iodomethane to react, then precipitating the reaction product in a second organic solvent, filtering and drying it, then dissolving it again in a third organic solvent, uniformly coating it on a substrate and drying it, and after ion exchange, obtaining the norbornene-containing bisbenzocyclobutane-based polyarylpiperidine anion exchange membrane shown in Formula 1.

[0060] In a preferred embodiment, the reaction temperature is 50°C and the reaction time is 48–72 hours.

[0061] In a preferred embodiment, the first organic solvent is any one of dimethyl sulfoxide, N-methylpyrrolidone, N,N-dimethylformamide, or N,N-dimethylacetamide.

[0062] In a preferred embodiment, the amount of the first organic solvent is 50 to 100 times the mass of the protonated norbornene-containing bisbenzocyclobutane polyarylpiperidine polymer.

[0063] In a preferred embodiment, the second organic solvent is any one of ethyl acetate, methanol, ethanol, acetone, or diethyl ether.

[0064] In a preferred embodiment, the amount of the second organic solvent is 10 to 20 times the volume of the first organic solvent.

[0065] In a preferred embodiment, the third organic solvent is any one of dimethyl sulfoxide, N-methylpyrrolidone, N,N-dimethylformamide, or N,N-dimethylacetamide.

[0066] In a preferred embodiment, the amount of the third organic solvent is 30 to 40 times the mass of the norbornene-containing bisbenzocyclobutane-based polyarylpiperidine anion exchange membrane material.

[0067] As a preferred embodiment, the method for preparing the protonated norbornene-containing bisbenzocyclobutane-based polyarylpiperidine polymer includes: Under a nitrogen atmosphere and in an ice-water bath, bisbenzocyclobutane monomers containing norbornene, linear phenyl monomers, and N-methyl-4-piperidinone were added to a reaction vessel. Then, a fourth organic solvent was added, and after stirring, trifluoroacetic acid (TFA) and trifluoromethanesulfonic acid (TFSA) were added dropwise to the solution. The reaction was carried out for 6-12 hours. The resulting viscous solution was poured into a fifth organic solvent, and a white polymer precipitate was formed. The precipitate was then washed with deionized water until the pH value was neutral and dried in a vacuum oven at 80°C for 12-24 hours to obtain the final product.

[0068] Preferably, the molar ratio of the norbornene-containing bisbenzocyclobutane monomer and the linear phenyl monomer is (1~50):(99~50).

[0069] Preferably, the molar ratio of the linear phenyl monomer and N-methyl-4-piperidinone is 1:(1~1.5).

[0070] Preferably, the molar ratio of trifluoroacetic acid to N-methyl-4-piperidinone is (1~2):1.

[0071] Preferably, the molar ratio of trifluoromethanesulfonic acid to N-methyl-4-piperidinone is (8~12):1.

[0072] In a preferred embodiment, the fourth organic solvent includes, but is not limited to, any one of dichloromethane, chloroform, or tetrahydrofuran.

[0073] In a preferred embodiment, the amount of the fourth organic solvent is 8 to 10 times the amount of N-methyl-4-piperidinone.

[0074] In a preferred embodiment, the fifth organic solvent is any one of ethyl acetate, methanol, ethanol, diethyl ether, tetrahydrofuran, or acetone, but is not limited thereto.

[0075] In a preferred embodiment, the amount of the fifth organic solvent is 40 to 50 times the volume of the fourth organic solvent.

[0076] As one of the objectives of this invention, the present invention also provides an application of the norbornene-containing bisbenzocyclobutane-based polyarylpiperidine anion exchange membrane material as described above in an alkaline water electrolyzer.

[0077] As one of the objectives of the invention, the present invention also provides an alkaline water electrolyzer, including an electrolyte membrane, wherein the electrolyte membrane comprises the norbornene-containing dibenzocyclobutane-based polyarylpiperidine anion exchange membrane material as described above.

[0078] The present invention will now be described in detail with reference to specific embodiments. It should be noted that the following embodiments are only used to further illustrate the present invention and should not be construed as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the content of the present invention still fall within the scope of protection of the present invention.

[0079] All raw materials used in the embodiments of this invention were purchased from the market.

[0080] The instruments and equipment used in the following examples are all conventional equipment in the relevant fields, and the performance tests are all conducted in accordance with the requirements of conventional standards.

[0081] Example 1

[0082] This embodiment provides a method for preparing a norbornene-containing dibenzocyclobutane-based polyarylpiperidine anion exchange membrane material. (See attached document for details.) Figure 2 The above is a synthetic route diagram for the norbornene-containing bisbenzocyclobutane-based polyarylpiperidine anion exchange membrane material provided in this embodiment. Specifically, the preparation method includes the following steps: (1) Preparation of trifluoroacetic acid protonated norbornene-containing bisbenzocyclobutane polyarylpiperidine polymers Under a nitrogen atmosphere, 1,9-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl (0.2274 g, 1.0 mmol), p-terphenyl (2.073 g, 9.0 mmol), and N-methyl-4-piperidinone (1.2448 g, 11 mmol) were added to a three-necked flask equipped with a mechanical stirrer, and the flask was covered with ice to more than half its volume. Then, 10 mL of dichloromethane and 1 mL of trifluoroacetic acid were added, and the mixture was stirred until homogeneous. Then, 12 mL of trifluoromethanesulfonic acid was added, and the reaction was carried out at 0 °C for 4 hours. The highly viscous solution was poured into methanol to precipitate the product, which was then cut into fragments and washed repeatedly with deionized water until the pH was neutral. Finally, it was dried in a vacuum oven at 80°C for 12 hours to obtain white solid fibers (PTP-C-Me-10%), with a yield of 92%.

[0083] The specific steps for preparing 1,9-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl include: adding 2-bromotoluene (3.4206 g, 20 mmol), 2,5-norbornadiene (0.9214 g, 10 mmol), palladium acetate (0.0449 g, 0.2 mmol), triphenylphosphine (0.1049 g, 0.4 mmol), and cesium carbonate (6.5164 g, 20 mmol) into a 350 mL pressure-resistant bottle, and then adding 100 mL of dioxane and stirring until homogeneous. The reaction was carried out at 150°C for 72 hours. After cooling to room temperature, the mixture was extracted with dichloromethane, filtered, rotary evaporated, and purified by column chromatography (developing solvent: pure petroleum ether) to obtain a white solid powder (a mixture of isomers of 1,9-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl), with a yield of 43%. Figure 1 The image shown is the 1H NMR spectrum of the monomer, proving that the synthesis was successful.

[0084] (2) Preparation of norbornene-containing bisbenzocyclobutane-based polyarylpiperidine anion exchange membrane materials

[0085] PTP-C-Me-10 (1 g) was added to a round-bottom flask and dissolved in 100 mL of DMSO. Then, potassium carbonate (2 g) and CH3I (9 g) were added. The mixture was magnetically stirred until homogeneous and reacted at 50 °C in the dark for 48 hours. The resulting solution was filtered, and the filtrate was poured into 1 L of ethyl acetate for precipitation. The precipitate was then filtered and dried in a vacuum oven at 80 °C for 12 hours to obtain a yellowish-brown solid powder (QPTP-C-Me-10%), with a yield of 88%. Where x = 10 and y = 90.

[0086] Example 2

[0087] This embodiment provides a method for preparing a norbornene-containing dibenzocyclobutane-based polyarylpiperidine anion exchange membrane material, including the following steps: The other steps are the same as in Example 1, except that in step (1), the mass of 1,9-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl is changed from 0.2274 g to 0.4548 g, and the mass of terphenyl is changed from 2.073 g to 1.8424 g. g, the molar ratio of 1,9-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl to p-terphenyl is 2:8; Finally, the anion exchange membrane material QPTP-C-Me-20% was obtained with a yield of 90%. Where x=20 and y=80.

[0088] Example 3

[0089] This embodiment provides a method for preparing a norbornene-containing dibenzocyclobutane-based polyarylpiperidine anion exchange membrane material, including the following steps: The other steps are the same as in Example 1, except that in step (1), the mass of 1,9-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl is changed from 0.2274 g to 0.6822 g, and the mass of terphenyl is changed from 2.073 g to 1.6121 g. g, the molar ratio of 1,9-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl to p-terphenyl is 3:7; Finally, the anion exchange membrane material QPTP-C-Me-30% was obtained with a yield of 91%. Where x=30 and y=70.

[0090] Example 4

[0091] This embodiment provides a method for preparing a norbornene-containing dibenzocyclobutane-based polyarylpiperidine anion exchange membrane material, including the following steps: The other steps are the same as in Example 1, except that in step (1), the mass of 1,9-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl is changed from 0.2274 g to 0.9096 g, and the mass of terphenyl is changed from 2.073 g to 1.3818 g. g, the molar ratio of 1,9-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl to p-terphenyl is 4:6; Finally, the anion exchange membrane material QPTP-C-Me-40% was obtained with a yield of 89%. Where x=40 and y=60.

[0092] Example 5

[0093] This embodiment provides a method for preparing a norbornene-containing dibenzocyclobutane-based polyarylpiperidine anion exchange membrane material, including the following steps: The other steps are the same as in Example 1, except that in step (1), the mass of 1,9-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl is changed from 0.2274 g to 1.1370 g, and the mass of terphenyl is changed from 2.073 g to 1.1515 g. g, the molar ratio of 1,9-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl / 1,6-dimethyl-4b,5,5a,9b,10,10a-hexahydro-5,10-methylenebenzo[3,4]cyclobutane[1,2-b]biphenyl to p-terphenyl is 5:5; Finally, the anion exchange membrane material QPTP-C-Me-50 was obtained with a yield of 92%. Where x=50 and y=50.

[0094] Comparative Example 1

[0095] This comparative example provides a method for preparing a linear polyarylpiperidine anion exchange membrane material without norbornene dibenzocyclobutane, including the following steps: (1) Preparation of trifluoroacetic acid protonated linear polyarylepiperidine polymers without norbornene and bisbenzocyclobutane 2.303 g (10 mmol) of terphenyl and 1.2448 g (11 mmol) of N-methyl-4-piperidinone were added to a three-necked flask equipped with a mechanical stirrer, and the flask was covered with an ice bath to more than half its volume. Then, 10 mL of dichloromethane and 1 mL of trifluoroacetic acid were added, and the mixture was stirred until homogeneous. Next, 12 mL of trifluoromethanesulfonic acid was added, and the reaction was carried out at 0 °C for 3 hours. The highly viscous solution was poured into methanol to precipitate the product, which was then cut into fragments and washed repeatedly with deionized water until the pH was neutral. Finally, the product was dried in a vacuum oven at 80 °C for 12 hours to obtain a pale yellow solid powder (PTP) in 93% yield.

[0096] (2) Preparation of linear polyarylpiperidine anion exchange membrane materials without norbornene and bisbenzocyclobutane

[0097] PTP (1 g) was added to a round-bottom flask and dissolved in 100 mL of DMSO. Then, potassium carbonate (2 g) and CH3I (9 g) were added. The mixture was magnetically stirred until homogeneous and reacted at 50°C in the dark for 48 hours. The resulting solution was filtered, and the filtrate was poured into 1 L of ethyl acetate for precipitation. The precipitate was then filtered again and dried in a vacuum oven at 80°C for 12 hours to obtain a yellowish-brown solid powder (QPTP) with a yield of 90%.

[0098] Comparative Example 2

[0099] This comparative example provides a method for preparing a high free volume polyarylpiperidine anion exchange membrane material (see Chinese Invention Patent CN117843933A), including the following steps: (1) Preparation of high free volume polyarylepiperidine polymers protonated by trifluoroacetic acid Terphenyl (2.1879 g, 9.5 mmol), N-methyl-4-piperidinone (1.2448 g, 11 mmol), and 2,7-dibromo-9,9'-spirodifluorene (0.2371 g, 0.5 mmol) were added to a three-necked flask equipped with a mechanical stirrer, and the flask was covered with an ice bath to more than half its volume. Then, 10 mL of dichloromethane and 1 mL of trifluoroacetic acid were added, and the mixture was stirred until homogeneous. Next, 12 mL of trifluoromethanesulfonic acid was added, and the reaction was carried out at 0 °C for 6 hours. The highly viscous solution was poured into methanol to precipitate the product, which was then cut into fragments and washed repeatedly with deionized water until the pH was neutral. Finally, the product was dried in a vacuum oven at 80 °C for 12 hours to obtain a pale yellow solid powder (PTP-CD-10%), with a yield of 93%.

[0100] The structural formula of the obtained polymer is shown below:

[0101] (2) Preparation of high free volume polyarylpiperidine anion exchange membrane material

[0102] PTP-CD-10% (1 g) was added to a round-bottom flask and dissolved in 100 mL of DMSO. Then, potassium carbonate (2 g) and CH3I (9 g) were added. The mixture was magnetically stirred until homogeneous and reacted at 50 °C in the dark for 48 hours. The resulting solution was filtered, and the filtrate was poured into 1 L of ethyl acetate for precipitation. The precipitate was then filtered and dried in a vacuum oven at 80 °C for 12 hours to obtain a yellowish-brown solid powder (QPTP-CD-10%), with a yield of 90%.

[0103] like Figure 3The figures shown are the norbornene-bisbenzocyclobutane-based linear polyarylpiperidine anion exchange membrane material prepared in the examples and the norbornene-bisbenzocyclobutane-based linear polyarylpiperidine anion exchange membrane material prepared in Comparative Example 1. 1 The 1H NMR (DMSO-d6) comparison diagram shows that the norbornene bisbenzocyclobutane-based linear polyarylpiperidine anion exchange membrane material of Example 4 was successfully prepared.

[0104] See Figure 4 The OH groups of the norbornene-containing bisbenzocyclobutane-based polyarylpiperidine anion exchange membrane materials provided in Examples 1-5 and Comparative Example 1 of this invention are OH groups. - The ion conductivity diagram shows that, as the content of norbornene dibenzocyclobutane copolymer increases, the conductivity of the anion exchange membrane significantly improves, and the OH content also increases. - The highest ionic conductivity can reach 169.3 mS / cm. -1 .

[0105] See Figure 5 The figures show the CO2 adsorption-desorption curves of the norbornene-containing bisbenzocyclobutane-based polyarylpiperidine anion exchange membrane materials provided in Examples 1-5 and Comparative Example 1 of this invention. As can be seen from the figures, the specific surface area S of the materials obtained in Examples 1-5 is... BET 81 m in sequence 2 g -1 88 m 2 g -1 97m 2 g -1 and 119 m 2 g -1 126 m 2 g -1 The specific surface area S of Comparative Example 1 BET =67 m 2 g -1 With the introduction of the norbornene bisbenzocyclobutane structure, the polymer molecular chain conformation of the anion exchange membrane material becomes more distorted, the free volume increases, and thus more micropores are formed, greatly increasing the micropore content, which is more conducive to ion transport and improves the ionic conductivity of the anion membrane.

[0106] See Figures 6a-6f Comparative Example 1 of the present invention ( Figure 6a ) and Examples 1 to 5 (in order) Figure 6b , Figure 6c , Figure 6d , Figure 6fThe TEM images of the norbornene-containing bisbenzocyclobutane-based polyarylpiperidine anion exchange membrane materials provided are shown in the figures. As can be seen from the figures, Examples 1 to 5 have obvious phase separation structures, which are more conducive to the formation of ion transport channels, thereby improving ion transport efficiency and conductivity. In contrast, Comparative Example 1 shows a more uniform structure, and the phase separation phenomenon is not obvious.

[0107] The anion exchange capacity (IEC) of the anion exchange membranes obtained in the comparative examples and the embodiments was tested. The water absorption rate, swelling rate and OH- ion conductivity were also tested at 30°C and 80°C, respectively. The results are shown in Table 1.

[0108] Table 1. Performance comparison of anion exchange membrane materials obtained in the examples and comparative examples.

[0109] As shown in Table 1, the IEC value of the norbornene-containing dibenzocyclobutane-based polyarylpiperidine anion exchange membrane material provided by this invention is slightly lower than that of Comparative Example 1. Therefore, its water absorption rate and swelling rate at 30℃ and 80℃ are significantly lower than those of Comparative Example 1, while its conductivity is significantly higher. Compared with Comparative Example 2, the conductivity of all examples is significantly higher than that of Comparative Example 2, while the water absorption rate and swelling rate of the examples are lower than those of Comparative Example 2. This indicates that the anion exchange membrane prepared using the technical solution of this invention has very high dimensional stability and mechanical strength, and at the same time, it exhibits high conductivity, indicating that the OH groups inside the material... - High ion transport efficiency improves its performance, such as increasing the efficiency of hydrogen production through water electrolysis. Clearly, the norbornene-bisbenzocyclobutane-based polyarylpiperidine anion exchange membrane material provided by this invention effectively improves the chemical stability of the membrane material. The norbornene-bisbenzocyclobutane structure not only enhances the structural rigidity and tortuosity of the polymer skeleton and increases the free volume between polymer chains, but also promotes the formation of numerous micropores, effectively improving the ion conductivity of the membrane material. Simultaneously, it suppresses the problem of poor dimensional stability caused by excessive water absorption. The prepared anion exchange membrane can significantly improve hydrogen production efficiency in the field of water electrolysis, giving it broader application prospects.

[0110] In addition, the inventors of this case also conducted experiments with other raw materials, process operations, and process conditions described in this specification, referring to the aforementioned embodiments, and obtained relatively ideal results in all cases.

[0111] Although the invention has been described with reference to illustrative embodiments, those skilled in the art will understand that various other changes, omissions, and / or additions can be made without departing from the spirit and scope of the invention, and that elements of the described embodiments can be substituted with substantially equivalents. Furthermore, many modifications can be made without departing from the scope of the invention to adapt particular situations or materials to the teachings of the invention. Therefore, this document is not intended to limit the invention to the specific embodiments disclosed for carrying out the invention, but rather to include all embodiments falling within the scope of the appended claims.

Claims

1. A norbornene bisbenzocyclobutene polyarylpiperidine anion exchange membrane, characterized by, The polylaryl piperidine polymer main chain is formed by introducing aromatic hydrocarbon into piperidone to react, to form a space structure which is twisted and difficult to rotate.

2. The norbornene bis-benzocyclobutene polyarylpiperidine anion exchange membrane according to claim 1, characterized by: The structural formula is shown in formula (I). Formula (I) Wherein, x is the mole ratio of the norbornene bis-bicycloalkane unit in the polymer, y is the mole ratio of the linear structure unit in the polymer, x is 10-50, y is 50-90, and x:y=(10-50):(50-90). The Ar1 is a norbornene bis-bicycloalkane monomer, and the Ar2 is a linear structure phenyl monomer.

3. The norbornene bis-benzocyclobutene polyarylpiperidine anion exchange membrane of claim 2, wherein: The norbornene bis-bicycloalkane monomer is any one of the following structural formula: ； And / or, the linear structure phenyl monomer is any one of the following structure: Wherein, (a) is biphenyl, (b) is terphenyl, and (c) is quaterphenyl.

4. A method for producing a norbornene bisbenzocyclophosphetane polyarylpiperidine anion exchange membrane according to any one of claims 1 to 3, characterized by, It comprises the following steps: The protonated norbornene bis-bicycloalkane polylaryl piperidine polymer is reacted with iodomethane to obtain the norbornene bis-bicycloalkane polylaryl piperidine polymer shown in formula (I).

5. The production method according to claim 4, characterized by, It comprises: The protonated norbornene bis-bicycloalkane polylaryl piperidine polymer is dissolved in a first organic solvent at 50°C, then iodomethane is added for reaction, then the reaction product is precipitated in a second organic solvent, filtered and dried, then dissolved in a third organic solvent again, uniformly coated on a substrate and dried, and after ion exchange, the norbornene bis-bicycloalkane polylaryl piperidine anion exchange membrane shown in formula (I) is obtained.

6. The method of claim 5, wherein: The reaction temperature is 50°C, and the reaction time is 48-72 hours; And / or, the first organic solvent is at least one of dimethyl sulfoxide, N-methyl pyrrolidone, N, N-dimethylformamide, and N, N-dimethylacetamide; And / or, the amount of the first organic solvent is 50-100 times the mass of the protonated norbornene bis-bicycloalkane polylaryl piperidine polymer; And / or, the second organic solvent is at least one of ethyl acetate, methanol, ethanol, acetone, and diethyl ether; And / or, the amount of the second organic solvent is 10-20 times the volume of the first organic solvent; And / or, the third organic solvent is at least one of dimethyl sulfoxide, N-methyl pyrrolidone, N, N-dimethylformamide, and N, N-dimethylacetamide; And / or, the amount of the third organic solvent is 30-40 times the mass of the norbornene bis-bicycloalkane polylaryl piperidine anion exchange membrane material.

7. The method of any one of claims 4-6, wherein, The protonated norbornene bis-bicycloalkane polylaryl piperidine polymer has a general structure shown in formula (II): Formula (II); Wherein, x is the mole ratio of the norbornene bis-bicycloalkane unit in the polymer, y is the mole ratio of the linear structure unit in the polymer, x is 1-50, y is 50-99, and x:y=(1-50):(99-50); The Ar1 is a norbornene bis-bicycloalkane monomer, and the Ar2 is a linear structure phenyl monomer.

8. The preparation method according to claim 7, characterized in that, The preparation method of the protonated norbornene-containing bisbenzocyclobutane polyarylpiperidine polymer includes: adding norbornene-containing bisbenzocyclobutane monomers, linear phenyl monomers, and N-methyl-4-piperidinone to a reaction vessel under a nitrogen atmosphere and an ice-water bath; then adding a fourth organic solvent; stirring; and then adding trifluoroacetic acid (TFA) and trifluoromethanesulfonic acid (TFSA) dropwise to the solution; reacting for 6-12 hours; pouring the resulting viscous solution into a fifth organic solvent; precipitating a white polymer precipitate; washing with deionized water until the pH is neutral; and drying in a vacuum oven at 80°C for 12-24 hours to obtain the polymer. The molar ratio of the norbornene-containing bisbenzocyclobutane monomer and the linear phenyl monomer is (1~50):(99~50). And / or, the molar ratio of the linear phenyl monomer and N-methyl-4-piperidinone is 1:(1~1.5). And / or, the molar ratio of the trifluoroacetic acid and N-methyl-4-piperidinone is (1~2):1; And / or, the molar ratio of the trifluoromethanesulfonic acid and N-methyl-4-piperidinone is (8~12):1; And / or, the fourth organic solvent is dichloromethane, chloroform, or tetrahydrofuran; And / or, the amount of the fourth organic solvent is 8 to 10 times the amount of N-methyl-4-piperidinone; And / or, the fifth organic solvent is any one of ethyl acetate, methanol, ethanol, diethyl ether, tetrahydrofuran, and acetone; And / or, the amount of the fifth organic solvent is 40 to 50 times the volume of the fourth organic solvent.

9. The application of a norbornene-containing bisbenzocyclobutane-based polyarylpiperidine anion exchange membrane material as described in any one of claims 1-3 in an alkaline water electrolyzer.

10. An alkaline water electrolyzer, comprising an electrolyte membrane, said electrolyte membrane comprising the norbornene-containing bisbenzocyclobutane-based polyarylpiperidine anion exchange membrane material as described in any one of claims 1-3.

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