Imidazolidinone compounds, porous organic polymer gels, and preparation methods and applications thereof

Abstract

The present invention belongs to the field of functional porous materials, and particularly relates to imidazolidinone compounds, porous organic polymer gels, and their preparation methods and applications. The present invention uses amino acid amide monomers and pyridine aldehyde monomers as raw materials to prepare a positively charged porous organic polymer gel in one step. The porous organic polymer gel has good processing performance and high conductivity.

Description

Technical Field

[0001] The present invention belongs to the field of functional porous materials, and particularly relates to imidazolidinone compounds, porous organic polymer gels, and their preparation methods and applications. Background Art

[0002] Developing materials with efficient ion conduction is very important for high-performance electrochemical applications, such as fuel cells, electrolytes, supercapacitors, etc. A fuel cell is an electrochemical device that can directly convert the chemical energy of a fuel (such as hydrogen or methanol) into electrical energy. Among them, alkaline fuel cells use anion conduction and have many advantages compared with proton-conducting acidic fuel cells, including fast reaction kinetics and the need not to use noble metal catalysts. Despite these advantages, developing materials capable of achieving efficient anion conduction remains a challenge.

[0003] Currently, most porous organic polymers used for anion conduction are in the form of membranes. For example, in 2023, Jiang et al. prepared a series of self-supporting COF membranes through a phase transfer polymerization process. The prepared QA-COF membrane has a high hydroxide ion conductivity. Polymers that can efficiently conduct anions (such as OH − and Cl − ) usually contain positively charged groups in their molecular structures. The cationic functional groups can be directly or indirectly bonded to the polymer backbone through covalent bonds. In 2024, Zhu et al. successfully prepared continuously porous aromatic frameworks (PAFs) membranes with adjustable thickness by liquid-solid interfacial polymerization. The rigid framework and stable C−C coupling endow it with excellent chemical stability, showing a OH 1 conductivity of 356.6 mS∙cm − at 80 °C and 98% relative humidity, which is also the highest value reported in anion exchange membranes (AEMs) so far.

[0004] However, for membranes, the balance between ion exchange capacity and size stability needs to be considered. Since the presence of water is beneficial to anion conduction, it can make the anion exchange membrane (AEM) have a high degree of dissociation and ion exchange capacity (IEC), thereby improving the mobility and conductivity of anions. However, in most of the reported chain polymer anion conductors, excessive water content will lead to the problem of chain polymer swelling, while low water content will lead to slow hydroxide migration. Gels do not need to consider this, because different-shaped and -sized voids are randomly generated during the formation of gels, which provides the possibility for promoting the migration and diffusion of guest molecules.

[0005] Ionic porous organic polymers (iPOPs) are a new type of porous organic polymers with ionic sites in their frameworks or pores. Compared with neutral porous organic polymers, the introduction of charges into the polymer structure can provide electrostatic interactions for these materials, enhancing their molecular recognition and conduction abilities. Currently, most iPOPs are obtained through the direct polymerization of charged monomers or post-modification with charged molecules after synthesis. Many synthetic methods have problems such as unsatisfactory reaction efficiency, limited tunability of monomer structures, and the blockage of porous channels by the modification of charged molecules after synthesis. In addition, most iPOPs exist in the form of powders, with poor processability, which limits their practical applications. Generally, solution processing methods can endow iPOPs with certain processability, but they require cumbersome treatment of samples, and some methods highly rely on the adjustment of pH value to maintain ionic properties, restricting their potential uses. Therefore, the development of efficient synthetic chemical methods for in-situ preparation of processable iPOP gels with tunable chemical structures can bring new opportunities for the potential applications of iPOPs. Summary of the Invention

[0006] The object of the present invention is to provide a preparation method using amino acid amide and pyridine aldehyde as raw materials and a positively charged imidazolidinone compound prepared by this method. The present invention further introduces this type of reaction into the synthesis of polymers to obtain a five-membered ring positively charged ionic porous organic polymer gel, which exhibits good processability and hydroxide conductivity and other properties.

[0007] The first technical problem to be solved by the present invention is to provide a preparation method for imidazolidinone compounds. The preparation method includes the following steps: reacting amino acid amide hydrochloride with pyridine aldehyde in an organic solvent to obtain the imidazolidinone compound ; wherein, the structural formula of the amino acid amide hydrochloride is , R 1 is selected from H, C 1-8 alkyl, phenyl-substituted C 1-4 alkyl, hydroxyl-substituted C 1-4 alkyl, carboxyl-substituted C 1-4 alkyl, -C 1-4 alkyl-CONH 2 , methylthio-substituted C 1-4 alkyl, mercapto-substituted C 1-4 alkyl; R 2 is selected from C 1-12 alkyl, C 1-4 haloalkyl, C 3-6 cycloalkyl, phenyl, C 1-4 alkoxy-substituted phenyl, nitro-substituted phenyl, carboxyl-substituted C 1-4 alkyl, A single amino acid group with one amino group removed, a polypeptide group composed of 2 - 10 amino acids with one amino group removed, n = 1 - 500; the pyridine aldehyde structural formula is , R 3 is selected from H, halogen, C 1-4 alkyl, C 1-4 alkoxy, C 1-4 haloalkyl, amide group, ester group, phenyl.

[0008] Furthermore, in the preparation method of the above imidazolidinone compounds, R 1 is selected from H, methyl, isopropyl, i-Bu, hydroxymethyl, benzyl, and R 2 is selected from methyl, -CH 2 CF 3 , cyclopropyl, phenyl, p-methoxyphenyl, p-nitrophenyl, , .

[0009] Preferably, in the preparation method of the above imidazolidinone compounds, the amino acid amide hydrochloride is selected from: glycine-N-methylamide hydrochloride, (S)-2-amino-N-methylpropanamide hydrochloride, (S)-2-amino-3-methyl-N-phenylbutanamide hydrochloride, (S)-2-amino-N-methyl-3-phenylpropanamide hydrochloride, (R)-2-amino-N-methyl-3-phenylpropanamide hydrochloride, 2-amino-N-(2,2,2-trifluoroethyl)acetamide hydrochloride, 2-amino-N-cyclopropylethanamide hydrochloride, N1-phenylglycinamide hydrochloride, 2-amino-N-(4-methoxyphenyl)acetamide hydrochloride, L-leucine-4-nitroaniline hydrochloride, L-alanine-4-nitroaniline hydrochloride, glycylglycine hydrochloride.

[0010] Furthermore, in the preparation method of the above imidazolidinone compounds, R 3 is selected from H, methyl, Cl, methoxy, -CF 3 .

[0011] Preferably, in the preparation method of the above imidazolidinone compounds, the pyridine aldehyde is selected from: pyridine-2-carboxaldehyde, 5-methylpyridine-2-carboxaldehyde, 5-methoxypyridine-2-carboxaldehyde, 5-chloropyridine-2-carboxaldehyde, 5-trifluoromethylpyridine-2-carboxaldehyde.

[0012] Furthermore, in the preparation method of the above imidazolidinone compounds, the molar ratio of the amino acid amide hydrochloride to the pyridine aldehyde is 1 : 1 - 10.

[0013] Further, in the preparation method of the above imidazolidinone compounds, the organic solvent is selected from acetic acid (HOAC), dimethyl sulfoxide (DMSO), N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAC), ethanol (EtOH), and n-butanol (n-BuOH). Preferably, it is acetic acid (HOAC).

[0014] Further, in the preparation method of the above imidazolidinone compounds, the molar volume ratio of the amino acid amide hydrochloride to the organic solvent is 1 mmol : 1 - 15 mL.

[0015] Further, in the preparation method of the above imidazolidinone compounds, the reaction temperature is 25 - 80 °C, and the reaction time is 10 minutes - 24 hours. Preferably, it is 10 minutes - 12 hours.

[0016] The second technical problem to be solved by the present invention is to provide imidazolidinone compounds prepared by the above preparation method of imidazolidinone compounds.

[0017] Specifically, the above imidazolidinone compounds have a structural formula as shown in formula ( )

[0018]

[0019] Formula ( )

[0020] wherein, R 1 is selected from H, C 1-8 alkyl, phenyl-substituted C 1-4 alkyl, hydroxy-substituted C 1-4 alkyl, carboxy-substituted C 1-4 alkyl, -C 1-4 alkyl-CONH 2 、methylthio-substituted C 1-4 alkyl, mercapto-substituted C 1-4 alkyl; R 2 is selected from C 1-12 alkyl, C 1-4 haloalkyl, C 3-6 cycloalkyl, phenyl, C 1-4 alkoxy-substituted phenyl, nitro-substituted phenyl, carboxy-substituted C 1-4 alkyl, , a single amino acid group with one amino group removed, a polypeptide group formed by 2 - 10 amino acids with one amino group removed, n = 1 - 500, R 3 is selected from H, halogen, C 1-4 alkyl, C 1-4 alkoxy, C 1-4 haloalkyl, amide group, ester group, phenyl.

[0021] Preferably, in the above imidazolidinone compounds, R 1 is selected from H, methyl, isopropyl, i-Bu, hydroxymethyl, benzyl, and R 2 is selected from methyl, -CH 2 CF 3 , cyclopropyl, phenyl, p-methoxyphenyl, p-nitrophenyl, , , and R 3 is selected from H, methyl, Cl, methoxy, -CF 3 .

[0022] Furthermore, the above imidazolidinone compounds are selected from the following specific structures:

[0023] .

[0024] The present invention also provides an imidazolidinone compound or its stereoisomer having the structure shown in formula ( ):

[0025]

[0026] Formula ( )

[0027] wherein, R 1 is selected from H, C 1-8 alkyl, phenyl-substituted C 1-4 alkyl, hydroxy-substituted C 1-4 alkyl, carboxy-substituted C 1-4 alkyl, -C 1-4 alkyl-CONH 2 , methylthio-substituted C 1-4 alkyl, mercapto-substituted C 1-4 alkyl; R 2 is selected from C 1-12 alkyl, C 1-4 haloalkyl, C 3-6 cycloalkyl, phenyl, C 1-4 alkoxy-substituted phenyl, nitro-substituted phenyl, carboxy-substituted C 1-4 alkyl, , a single amino acid group with one amino group removed, a polypeptide group formed by 2-10 amino acids with one amino group removed, n = 1-500, and R 3 is selected from H, halogen, C 1-4 alkyl, C 1-4 alkoxy, C 1-4 haloalkyl, amido, ester, phenyl.

[0028] Preferably, in the above imidazolidinone compound or its stereoisomer, R1 Selected from H, methyl, isopropyl, i-Bu, hydroxymethyl, benzyl, R 2 Selected from methyl, -CH 2 CF 3 , cyclopropyl, phenyl, p-methoxyphenyl, p-nitrophenyl, , , R 3 Selected from H, methyl, Cl, methoxy, -CF 3 .

[0029] Furthermore, the above-mentioned imidazolidinone compounds or their stereoisomers are selected from the following specific structures:

[0030] .

[0031] The third technical problem to be solved by the present invention provides a preparation method of an ionic porous organic polymer gel. The preparation method includes the following steps: reacting an amino acid amide monomer and a pyridine aldehyde monomer in an organic solvent to obtain the ionic porous organic polymer gel; wherein, the structural formula of the amino acid amide monomer is , R 1 Selected from H, C 1-8 alkyl, phenyl-substituted C 1-4 alkyl, hydroxyl-substituted C 1-4 alkyl, carboxyl-substituted C 1-4 alkyl, -C 1-4 alkyl-CONH 2 、methylthio-substituted C 1-4 alkyl, mercapto-substituted C 1-4 alkyl; R 2 Selected from C 1-12 alkyl, C 1-4 haloalkyl, C 3-6 cycloalkyl, phenyl, C 1-4 alkoxy-substituted phenyl, nitro-substituted phenyl, carboxyl-substituted C 1-4 alkyl, , , a single amino acid group with one amino group removed, a polypeptide group formed by 2-10 amino acids with one amino group removed, n = 1-500; the pyridine aldehyde monomer is selected from [3,3'-bipyridine]-6,6'-dialdehyde or 1,3,5-tris(2-formylpyridin-5-yl)benzene.

[0032] Further, in the above preparation method of the ionic porous organic polymer gel, R 1 Selected from H, methyl, isopropyl, i-Bu, hydroxymethyl, benzyl, R 2 Selected from methyl, -CH 2 CF 3, cyclopropyl, phenyl, p-methoxyphenyl, p-nitrophenyl, , , .

[0033] Preferably, in the preparation method of the above ionic porous organic polymer gel, the amino acid amide monomer is selected from: glycine-N-methylamide hydrochloride, (S)-2-amino-N-methylpropanamide hydrochloride, (S)-2-amino-3-methyl-N-phenylbutanamide hydrochloride, (S)-2-amino-N-methyl-3-phenylpropanamide hydrochloride, (R)-2-amino-N-methyl-3-phenylpropanamide hydrochloride, 2-amino-N-(2,2,2-trifluoroethyl)acetamide hydrochloride, 2-amino-N-cyclopropylethanamide hydrochloride, N1-phenylglycinamide hydrochloride, 2-amino-N-(4-methoxyphenyl)acetamide hydrochloride, L-leucine-4-nitroaniline hydrochloride, L-alanine-4-nitroaniline hydrochloride, , glycylglycine hydrochloride.

[0034] Preferably, in the preparation method of the above ionic porous organic polymer gel, the pyridine aldehyde monomer is selected from: [3,3'-bipyridine]-6,6'-dialdehyde (the structural formula is ) or 1,3,5-tris(2-formylpyridin-5-yl)benzene (the structural formula is ).

[0035] Further, in the preparation method of the above ionic porous organic polymer gel, the molar ratio of the amino acid amide monomer to the pyridine aldehyde monomer is 1 - 4:2. Preferably 3:2, 1:2 or 3:4.

[0036] Further, in the preparation method of the above ionic porous organic polymer gel, the organic solvent is dimethyl sulfoxide (DMSO).

[0037] Further, in the preparation method of the above ionic porous organic polymer gel, the molar volume ratio of the amino acid amide monomer to the organic solvent is 0.1 - 0.3 mmol:1 mL.

[0038] Further, in the preparation method of the above ionic porous organic polymer gel, the reaction temperature is 90 - 120 °C. The reaction time is 3 hours - 3 days.

[0039] The fourth technical problem to be solved by the present invention is to provide an ionic porous organic polymer gel prepared by the above preparation method of the ionic porous organic polymer gel.

[0040] The fifth technical problem to be solved by the present invention is to provide a xerogel prepared from the above ionic porous organic polymer gel.

[0041] Furthermore, the obtained ionic porous organic polymer hydrogel is processed into a xerogel. The xerogel can be obtained through solvent exchange and supercritical carbon dioxide drying. For example: the wet gel containing organic solvent is immersed in a solvent (such as DMF) for a period of time (such as 2 days), taken out and then immersed in a solvent (such as ethanol) for a period of time (such as 2 days), and then supercritical carbon dioxide drying is carried out to obtain the xerogel.

[0042] The sixth technical problem to be solved by the present invention is to use the obtained ionic porous organic polymer gel or xerogel above for anion conduction, heavy metal adsorption or gas separation.

[0043] The seventh technical problem to be solved by the present invention is to provide an anion conduction material. This anion conduction material is prepared by carrying out solvent exchange on the above-prepared ionic porous organic polymer gel or xerogel in a solution containing hydroxide ions. Preferably, the solution containing hydroxide ions is sodium hydroxide solution (1 mol / L) or potassium hydroxide solution (1 mol / L).

[0044] Advantages of the present invention:

[0045] The present invention provides a methodology that can be generally applicable to the synthesis of a new five-membered ring positively charged substance. This method has the advantages of one-pot reaction, simple reaction operation, short reaction time, mild reaction conditions, no need for harsh conditions such as anhydrous and anaerobic, and the yield is basically as high as 95%. Furthermore, the method is further used to synthesize an ionic porous organic polymer gel with a positively charged five-membered ring. The synthesized gel not only has excellent processability, but also generates charged substances in-situ without post-modification, and the synthesis method is simple. The polymer backbone is positively charged, and its counter ion is chloride ion. The chloride ion can be replaced by hydroxide ion through simple solvent exchange, and excellent anion conduction performance is exhibited. The obtained anion conduction material has an anion conductivity of 186 mS cm under the conditions of 80 °C and 100%RH -1 , and its conductivity is at a leading level among the reported amorphous porous organic polymer materials currently. Description of the drawings

[0046] Figure 1 Structures of amide and pyridine aldehyde raw materials used in the imidazolidinone compounds of the present invention are listed

[0047] Figure 2 Structures of amide monomers and pyridine aldehyde monomers used in the ionic porous organic polymers of the present invention are listed

[0048] Figure 3 Enumeration of imidazolidinone compounds and ionic porous organic polymer structures of the present invention

[0049] Figure 4 Physical pictures of ionic porous organic polymer gels in Examples 7, 10 - 13

[0050] Figure 5 Infrared spectra of monomers and polymers corresponding to Examples 7, 10 - 13

[0051] Figure 6 N of polymers corresponding to Examples 7, 10 - 13 2 Adsorption - desorption and pore size distribution diagrams

[0052] Figure 7 Impedance diagrams of polymer MeG1 - Tpy in Example 7 at different temperatures under 100%RH

[0053] Figure 8 Impedance diagrams of polymers MeG1 - Tpy with different monomer concentrations in Examples 8, 9 at different temperatures under 100%RH

[0054] Figure 9 Impedance diagrams of polymers obtained in Examples 10 - 13 at different temperatures under 100%RH

[0055] Figure 10 Conductivity diagrams of polymers obtained in Examples 7 - 13 at different temperatures under 100%RH

[0056] Figure 11 Proton nuclear magnetic resonance spectrum of the product of Example 1

[0057] Figure 12 Carbon nuclear magnetic resonance spectrum of the product of Example 1

[0058] Figure 13 Proton nuclear magnetic resonance spectrum of the product of Example 2

[0059] Figure 14 Carbon nuclear magnetic resonance spectrum of the product of Example 2

[0060] Figure 15 Proton nuclear magnetic resonance spectrum of the product of Example 3

[0061] Figure 16 Carbon nuclear magnetic resonance spectrum of the product of Example 3

[0062] Figure 17 Proton nuclear magnetic resonance spectrum of the product of Example 4

[0063] Figure 18 Carbon nuclear magnetic resonance spectrum of the product of Example 4

[0064] Figure 19 1H NMR spectrum of the product of Example 5

[0065] Figure 20 13C NMR spectrum of the product of Example 5

[0066] Figure 21 13C NMR spectrum of the product of Example 6

[0067] Figure 22 13C NMR spectrum of the product of Example 6 Detailed implementation mode

[0068] The present invention first provides a preparation method of imidazolidinone compounds, which uses amino acid amide hydrochloride and pyridine aldehyde as raw materials to react in an organic solvent to obtain the imidazolidinone compounds. This reaction can obtain the positively charged imidazolidinone compounds in a one-pot reaction, with simple operation, short reaction time, mild reaction conditions, no need for harsh conditions such as anhydrous and anaerobic, and the yield is basically as high as 95%. Only by simply removing the solvent can the pure product be obtained.

[0069] The specific reaction path is as follows: (1) Amino acid amide hydrochloride and pyridine aldehyde undergo Schiff base condensation to form an imine intermediate (the first step); (2) Isomerization occurs at the amide of the imine intermediate to obtain an iminol intermediate (the second step); (3) The iminol intermediate undergoes an intramolecular cyclization reaction to form an imidazolidinone intermediate with a secondary amine (the third step); (4) By undergoing a second Schiff base condensation with pyridine aldehyde, an imidazolidinone product with an imine cation can be obtained (the fourth step).

[0070]

[0071] According to the above mechanism diagram, the structural formula of amino acid amide hydrochloride is , it is necessary to ensure that the amino acid amide raw material uses α-amino acid and contains primary amine and amide functional groups. The substituents at the R 1 and R 2 positions do not participate in the formation of the final product and do not affect the reaction. R 1 is applicable to the side chains of natural amino acids such as H, C 1-8 alkyl (preferably C 1-4 alkyl), phenyl-substituted C 1-4 alkyl, hydroxy-substituted C 1-4 alkyl, carboxy-substituted C 1-4 alkyl, -C 1-4 alkyl-CONH 2 , methylthio-substituted C 1-4 alkyl, mercapto-substituted C 1-4 alkyl, etc.; R 2 is selected from C 1-12 alkyl (preferably C1-8 alkyl group, more preferably C 1-4 alkyl group), C 1-4 haloalkyl group, C 3-6 cycloalkyl group, phenyl group, C 1-4 phenyl group substituted with alkoxy group, phenyl group substituted with nitro group, C substituted with carboxyl group 1-4 alkyl group, , a single amino acid group with one amino group removed, a polypeptide group formed by 2 - 10 amino acids with one amino group removed, etc., n = 1 - 500, preferably n = 1 - 400. n = 1 - 300. n = 1 - 200. n = 1 - 100. n = 1 - 50. n = 1 - 20. n = 1 - 10. The structural formula of pyridine aldehyde is , R 3 is selected from H, halogen, C 1-4 alkyl group, C 1-4 alkoxy group, C 1-4 haloalkyl group, amide group, ester group, phenyl group, etc. Further, R 1 is selected from H, methyl group, isopropyl group, i - Bu, hydroxymethyl group, benzyl group, R 2 is selected from methyl group, -CH 2 CF 3 , cyclopropyl group, phenyl group, p - methoxyphenyl group, p - nitrophenyl group, -CH 2 COOH, . Most preferably, the amino acid amide hydrochloride is selected from: glycine - N - methylamide hydrochloride, (S)-2 - amino - N - methylpropanamide hydrochloride, (S)-2 - amino - 3 - methyl - N - phenylbutanamide hydrochloride, (S)-2 - amino - N - methyl - 3 - phenylpropanamide hydrochloride, (R)-2 - amino - N - methyl - 3 - phenylpropanamide hydrochloride, 2 - amino - N-(2,2,2 - trifluoroethyl)acetamide hydrochloride, 2 - amino - N - cyclopropylethanamide hydrochloride, N1 - phenylglycinamide hydrochloride, 2 - amino - N-(4 - methoxyphenyl)acetamide hydrochloride, L - leucine - 4 - nitroaniline hydrochloride, L - alanine - 4 - nitroaniline hydrochloride, glycylglycine hydrochloride. Most preferably, the pyridine aldehyde is selected from: pyridine - 2 - carbaldehyde, 5 - methylpyridine - 2 - carbaldehyde, 5 - methoxypyridine - 2 - carbaldehyde, 5 - chloropyridine - 2 - carbaldehyde, 5 - trifluoromethylpyridine - 2 - carbaldehyde.

[0072] For the raw material amino acid amide hydrochloride of the present invention , an amino acid raw material protected with tert - butyloxycarbonyl (Boc) at the N - terminal and a raw material with an amino group can be condensed by conventional methods in the art and deprotected under acidic conditions to form a salt. Therefore, for R 2 , as long as it is a raw material with an amino group. Therefore, for the raw material with an amino group , which can be a single amino acid or a polypeptide formed by multiple amino acids, preferably 2 - 10 amino acids, 2 - 8 amino acids, 2 - 6 amino acids, or 2 - 4 amino acids. Therefore, for R 2 can be a single amino acid group with one amino group removed or a polypeptide group with one amino acid removed.

[0073] In the preparation method of the above imidazolidinone compounds, the reaction temperature is generally from room temperature to 80 °C. For raw materials with less steric hindrance, the reaction can be carried out at room temperature, while those with larger steric hindrance require reaction at 80 °C. The reaction temperature can be reasonably selected according to the raw materials. The reaction time is 10 minutes - 24 hours. Preferably 10 minutes - 12 hours.

[0074] In the preparation method of the above imidazolidinone compounds, the organic solvent used in the reaction is selected from acetic acid, dimethyl sulfoxide, N,N - dimethylformamide, N,N - dimethylacetamide, ethanol, and n - butanol. Preferably acetic acid.

[0075] In the present invention, small molecules are used as raw materials to verify the feasibility of the tandem condensation - cyclization - condensation reaction, and then this reaction is further applied to the preparation of positively charged ionic porous organic polymer gels. Furthermore, an ionic porous organic polymer gel and its preparation method are provided. The preparation method includes the following steps: reacting an amino acid amide monomer and a pyridine aldehyde monomer in an organic solvent to obtain the ionic porous organic polymer gel; wherein, the structural formula of the amino acid amide monomer is , and the pyridine aldehyde is a substance with a pyridine aldehyde structure; the amino acid amide monomer is monofunctional or bifunctional, and the pyridine aldehyde monomer is bifunctional or trifunctional.

[0076] Furthermore, the amino acid amide monomer, pyridine aldehyde monomer, and reaction solvent are ultrasonically treated to fully dissolve the organic monomers, and then added to a syringe (5 mL), placed in an oven at 90 - 120 °C for reaction for 3 hours - 3 days. After the reaction is completed, the gel is pushed out of the syringe to obtain a complete ionic porous organic polymer.

[0077] In the preparation method of the above ionic porous organic polymer gel, R 1 is selected from H, C 1-8 alkyl (preferably C 1-4 alkyl), phenyl - substituted C 1-4 alkyl, hydroxy - substituted C 1-4 alkyl, carboxy - substituted C 1-4 alkyl, -C 1-4 alkyl - CONH 2 , methylthio - substituted C 1-4 alkyl, mercapto - substituted C 1-4 alkyl; R2 Selected from C 1-12 alkyl (preferably C 1-8 alkyl, more preferably C 1-4 alkyl), C 1-4 haloalkyl, C 3-6 cycloalkyl, phenyl, C 1-4 phenyl substituted with alkoxy, phenyl substituted with nitro, C substituted with carboxyl 1-4 alkyl, , a single amino acid group with one amino group removed, a polypeptide group formed by 2 - 10 amino acids with one amino group removed, , n = 1 - 500. Preferably n = 1 - 400. n = 1 - 300. n = 1 - 200. n = 1 - 100. Further, R 1 is selected from H, methyl, isopropyl, i - Bu, hydroxymethyl, benzyl, R 2 is selected from methyl, -CH 2 CF 3 , cyclopropyl, phenyl, p - methoxyphenyl, p - nitrophenyl, -CH 2 COOH, , . Most preferably, the amino acid amide monomer is selected from: glycine - N - methylamide hydrochloride, (S)-2 - amino - N - methylpropanamide hydrochloride, (S)-2 - amino - 3 - methyl - N - phenylbutanamide hydrochloride, (S)-2 - amino - N - methyl - 3 - phenylpropanamide hydrochloride, (R)-2 - amino - N - methyl - 3 - phenylpropanamide hydrochloride, 2 - amino - N-(2,2,2 - trifluoroethyl)acetamide hydrochloride, 2 - amino - N - cyclopropylethanamide hydrochloride, N1 - phenylglycinamide hydrochloride, 2 - amino - N-(4 - methoxyphenyl)acetamide hydrochloride, L - leucine - 4 - nitroaniline hydrochloride, L - alanine - 4 - nitroaniline hydrochloride, , glycylglycine hydrochloride.

[0078] In the preparation method of the above ionic porous organic polymer gel, for the raw material pyridine aldehyde monomer, any substance with a pyridine - 2 - carbaldehyde structure can be used. At the same time, in order to prepare the polymer, pyridine - 2 - carbaldehyde needs to be bifunctional or trifunctional. Preferably, the pyridine - 2 - carbaldehyde monomer is selected from: [3,3’ - bipyridine] - 6,6’ - dialdehyde or 1,3,5 - tris(2 - formylpyridin - 5 - yl)benzene.

[0079] In the preparation method of the above ionic porous organic polymer gel, it is preferred that the organic solvent is DMSO. In DMSO, the reaction rate can be reduced, and the interaction between the polymer and the solvent can be promoted, thus forming a gel.

[0080] Examples of the structures of the amino acid amide hydrochloride and pyridine aldehyde raw materials that can be used in the present invention are shown in Figure 1 , and examples of the structures of the amino acid amide monomer and pyridine aldehyde monomer raw materials that can be used are shown in Figure 2 . Examples of the structures of the imidazolidinone compounds and ionic porous organic polymers prepared in the present invention are shown in Figure 3 .

[0081] The experimental scheme of the present invention will be described in detail below with reference to examples. For raw materials, reagents or instruments, etc. whose manufacturers are not specified, they can all be obtained by purchasing commercially or prepared from conventional raw materials by existing methods.

[0082] Example 1 Synthesis of a five-membered ring positively charged ionic small molecule

[0083] Add glycine-N-methylamide hydrochloride (1 mmol), pyridine-2-carboxaldehyde (2 mmol) and acetic acid (3 mL) to a 10 mL sample bottle, react at 80 °C for 12 hours, and evaporate the solvent to obtain the final product ( Figure 11 and 12 ).

[0084] Examples 2-6

[0085] The preparation process and the ratio of reactants are the same as in Example 1, except that in step 1), the amino monomer is changed from glycine-N-methylamide hydrochloride to (S)-2-amino-N-methylpropanamide hydrochloride (Example 2, Figure 13 and 14 ), 2-amino-N-cyclopropylethanamide hydrochloride (Example 3, Figure 15 and 16 ), 2-amino-N-(4-methoxyphenyl)ethanamide hydrochloride (Example 4, Figure 17 and 18 ), (S)-2-amino-3-methyl-N-phenylbutanamide hydrochloride (Example 5, Figure 19 and 20 ), diglycine hydrochloride (Example 6, Figure 21 and 22 ) to react with pyridine-2-carboxaldehyde to form the corresponding products.

[0086] Example 7 Preparation of a five-membered ring positively charged porous organic polymer gel

[0087] 1) In a 10 mL sample bottle, add glycine-N-methylamide hydrochloride (0.1 mmol), 1,3,5-tris(2-formylpyridin-5-yl)benzene (0.066 mmol) and DMSO (1 mL), and ultrasonicate for 10 minutes to fully dissolve the monomers. Then transfer it to a 5 mL syringe and place it in an oven at 90 °C for reaction for 1 day. After the reaction, push out the gel from the syringe to obtain a complete black gel (MeG1-Tpy).

[0088] 2) Immerse the wet gel obtained in step 1) in N,N-dimethylformamide for 2 days, change the solvent every 12 hours. After two days, take it out and immerse it in ethanol for 2 days, change the solvent every 12 hours, and then dry it by supercritical carbon dioxide to obtain a dry gel (MeG1-Tpy).

[0089] Examples 8 - 9

[0090] The preparation process is the same as that in Example 7, except that in step 1), the monomer concentration is changed (i.e., the molar volume ratio of glycine-N-methylamide hydrochloride to DMSO in Example 7 is changed) to 0.2 mol / L (Example 8) and 0.3 mol / L (Example 9) respectively; gels can be obtained in both cases.

[0091] Examples 10 - 13

[0092] The preparation process is the same as that in Example 7, except only that in step 1), the amino monomer is changed from glycine-N-methylamide hydrochloride to (S)-2-amino-N-methylpropanamide hydrochloride (Example 10, polymer MeA1-Tpy), N1-phenylglycinamide hydrochloride (Example 11, polymer PhG1-Tpy), (Example 12, polymer PhG2-Tpy) reacts with 1,3,5-tris(2-formylpyridin-5-yl)benzene to form a polymer; in step 1), the aldehyde monomer is changed from 1,3,5-tris(2-formylpyridin-5-yl)benzene to [3,3'-bipyridine]-6,6'-dicarboxaldehyde and reacts to form a polymer (Example 13, polymer PhG2-Bpy). It is found that the corresponding gel structures can be obtained in all cases (as Figure 4 shown).

[0093] Example 14 Preparation of anionic conductive materials from ionic porous organic polymer gels after solvent exchange

[0094] Immerse the wet gel of MeG1-Tpy (Example 7) with a monomer concentration of 0.1 mol / L in 1 mol / L sodium hydroxide solution, take it out after soaking for 24 hours, and an anionic conductive material can be obtained.

[0095] Structural characterization

[0096] 1) Infrared spectra of polymers corresponding to different amino acid amide monomers

[0097] After the wet gel of the product obtained by reacting different amino acid amide monomers with pyridine aldehyde was dried completely, infrared tests were carried out on the samples. As Figure 5 shown: There is no peak at 2865 cm -1 in the spectrum of MeG1-Tpy, and this peak corresponds to the N-H vibration in monomer MeG1, indicating that glycine-N-methylamide hydrochloride was completely consumed. The peak appearing at 2925 cm -1 is attributed to the C-H vibration of methylene, which confirms that the amino acid derivative has been successfully incorporated into the polymer. In addition, the peak corresponding to the C=O vibration of the aldehyde group at 1698 cm -1 in MeG1-Tpy disappeared and a new peak appeared at 1683 cm -1 , which indicates that the aldehyde group was successfully converted into an imine, so it can be known from the infrared spectrum that the reaction occurred.

[0098] 2) N 2 adsorption-desorption spectra of polymers corresponding to different amino acid amide monomers

[0099] A certain amount of the sample was taken into a sample tube, and after vacuum drying pretreatment at 120 °C, the program was set to test the N 2 adsorption-desorption curve of the sample to obtain the specific surface area (BET). As Figure 6 shown, the adsorption-desorption curves of the five polymers (a is the adsorption-desorption curve of MeG1-Tpy, b is the pore size distribution of MeG1-Tpy; c is the adsorption-desorption curve of MeA1-Tpy, d is the pore size distribution of MeA1-Tpy; e is the adsorption-desorption curve of PhG1-Tpy, f is the pore size distribution of PhG1-Tpy; g is the adsorption-desorption curve of PhG2-Tpy, h is the pore size distribution of PhG2-Tpy; i is the adsorption-desorption curve of PhG2-Bpy, j is the pore size distribution of PhG2-Bpy) all show typical type II adsorption curves, among which MeG1-Tpy has the largest specific surface area, which is 681 m 2 g -1 . The pore size distribution shows that the ionic porous organic polymer contains micropores, mesopores and macropores at the same time, and the main size distribution is about 2 nm.

[0100] Electrochemical impedance experiment

[0101] The MeG1-Tpy obtained in Example 7 was placed in a hollow polytetrafluoroethylene gasket with a height of 0.2 cm, an outer diameter of 1.5 cm, and an inner diameter of 1 cm. The two ends were contacted with the sample using silver sheets with a diameter of 1.5 cm. Then, the gasket was clamped with electrodes, and the sample was placed in a constant temperature and humidity chamber. The humidity was adjusted to 100% RH, and the electrochemical impedance spectroscopy was measured at 30 - 80 °C using an electrochemical workstation. The conductivity was calculated according to σ = l / (A*R), where σ is the conductivity (mS cm -1 ), l is the electrode distance (cm), A is the contact area between the electrode and the sample (cm 2 ), and R is the impedance (Ω). As Figure 7 shown, MeG1-Tpy exhibited excellent anion conduction performance under different temperature conditions at 100% RH. At 80 °C and a relative humidity of 100% RH, the anion conductivity reached 164 mS cm -1 .

[0102] Under the same test conditions as above, the impedance of the polymers with different monomer concentrations in Examples 8 and 9 was measured at a relative humidity of 100% RH in the temperature range of 30 - 80 °C as Figure 8 shown (a corresponds to Example 8, b corresponds to Example 9). Figure 9 (a corresponds to Example 10, b corresponds to Example 11, c corresponds to Example 12, d corresponds to Example 13). It can be seen that as the monomer concentration increases, the conductivity decreases. The speculated reason is that the increase in monomer concentration leads to a more compact microstructure of the iPOP gel, thus blocking the ion transport channels and resulting in a decrease in ion conductivity.

[0103] Furthermore, under the same test conditions, the conductivity of the polymers corresponding to different amino acid amide monomers in Examples 7 - 13 was measured at a relative humidity of 100% RH in the temperature range of 30 - 80 °C as Figure 10 shown (a corresponds to Examples 7, 8, and 9 respectively). It was found that among the 5 polymers, when the amino acid derivative monomer was (S)-2-amino-N-methylpropanamide hydrochloride, the conductivity of the corresponding polymer MeA1-Tpy was the largest under the same conditions, reaching 186 mS cm -1 .

Claims

1. A method for preparing an ionic porous organic polymer gel, characterized in that: The method comprises the following steps: reacting an amino acid amide monomer and a pyridine aldehyde monomer in an organic solvent to obtain the ionic porous organic polymer gel; wherein the amino acid amide monomer is selected from the group consisting of glycine-N-methylamide hydrochloride, (S)-2-amino-N-methylpropionamide hydrochloride, (S)-2-amino-3-methyl-N-phenylbutyramide hydrochloride, (S)-2-amino-N-methyl-3-phenylpropionamide hydrochloride, (R)-2-amino-N-methyl-3-phenylpropionamide hydrochloride, 2-amino-N-(2 ,2,2-trifluoroethyl)acetamide hydrochloride, 2-amino-N-cyclopropylacetamide hydrochloride, N1-phenylglycinamide hydrochloride, 2-amino-N-(4-methoxyphenyl)acetamide hydrochloride, L-leucine-4-nitroaniline hydrochloride, L-alanine-4-nitroaniline hydrochloride, 4,4'-bis-glycinylamino-biphenyl-dihydrochloride, glycylglycine hydrochloride; the pyridine aldehyde monomer is selected from [3,3'-bipyridine]-6,6'-dicarboxaldehyde or 1,3,5-tris(2-formylpyridin-5-yl)benzene.

2. The method for preparing the ionic porous organic polymer gel according to claim 1, characterized in that: Satisfy at least one of the following: The molar ratio of the amino acid amide monomer to the pyridine aldehyde monomer is 1-4:2; The organic solvent is dimethyl sulfoxide; The molar volume ratio of the amino acid amide monomer to the organic solvent is 0.1 - 0.3 mmol: 1 mL; The reaction temperature is 90-120°C; The reaction time is 3 hours to 3 days.

3. An ionic porous organic polymer gel, characterized in that: The ionic porous organic polymer gel is prepared by the preparation method of claim 1 or 2.

4. An anion conducting material, characterized in that: The ionic porous organic polymer gel according to claim 3 or the dry gel prepared therefrom is prepared by subjecting the gel to solvent exchange in a solution containing hydroxide.

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