Pyridyl-doped vinyl porous organic polymer as well as preparation method and application thereof

Abstract

The invention relates to the technical field of vinyl porous organic polymers, and discloses a pyridyl-doped vinyl porous organic polymer as well as a preparation method and application thereof. The preparation method comprises the following steps: carrying out melt polymerization on 2, 4, 6-trimethylpyridine, an aromatic monomer, a pyridine-based modulator and a fluxing agent in a closed reactor to obtain a crude product; and purifying the crude product to obtain the pyridyl-doped vinyl porous organic polymer. Wherein the aromatic monomer is an aromatic compound containing two aldehyde functional groups. The pyridyl-doped vinyl porous organic polymer is prepared from the specific reaction monomer and the fluxing agent through a melt polymerization method, and the pyridyl-doped vinyl porous organic polymer has high surface area, high porosity and high stability, can be recycled when adsorbing HF acid in an electrolyte, and has very high application value and economic benefits. The preparation process is simple, the phenomena of high temperature and high pressure caused by the use of a large amount of organic solvents are avoided, and large-scale industrial production can be realized.

Description

Technical Field

[0001] The present application relates to the technical field of vinyl porous organic polymers, and in particular to a pyridine-doped vinyl porous organic polymer and a preparation method and application thereof. Background Art

[0002] Hydrogen fluoride is the main harmful byproduct in the electrolyte. Its formation mainly comes from the decomposition of electrolytes (such as LiPF6) and side reactions such as residual water. The presence of HF not only causes corrosion of electrode materials, dissolution of transition metals, and damage to the diaphragm structure, but also accelerates the decomposition reaction of the electrolyte, seriously threatening the cycle stability and safety of the battery system. In addition, the accumulation of HF may also trigger electrochemical side reactions, reduce energy density, and even cause safety accidents. Therefore, the development of efficient, stable, and sustainable HF adsorption materials is one of the key links to improve battery performance and extend battery life.

[0003] Currently, traditional HF capture materials, such as inorganic oxides, molecular sieves, and organic amines, suffer from low selectivity, low adsorption capacity, and poor structural stability, making them inadequate for efficient HF management in complex electrolyte environments. Furthermore, traditional HF capture materials are non-renewable and expensive to use. There is an urgent need to develop a new, highly efficient, selective, and long-term stable HF capture material to achieve precise HF management in electrolytes.

[0004] Covalent organic frameworks (COFs) are a class of crystalline, porous polymers with well-defined structures, high surface areas, excellent stability, adjustable pores, and designable functional groups. They provide ample adsorption sites and diffusion pathways for HF molecules. Through pore size regulation, they can selectively capture small acids such as HF while avoiding interference with electrolyte solvents or lithium salts. COFs can enhance their affinity for HF by introducing nitrogen- and oxygen-containing Lewis basic sites (e.g., pyridine, amine, and nitrile functional groups) into their molecular structure, enabling efficient complexation and capture of acidic molecules.

[0005] Based on this, it is of great significance to develop a stable and regenerable pyridine-doped vinyl porous organic HF adsorption material. Summary of the Invention

[0006] The present application provides a pyridine-doped vinyl porous organic polymer and its preparation method and application, aiming to solve the technical problems of poor structural stability and non-renewable utilization of existing HF capture materials.

[0007] In order to achieve the above objectives, this application adopts the following technical solutions.

[0008] In a first aspect of the present application, a preparation method of a pyridyl-doped vinyl porous organic polymer is provided, comprising:

[0009] melting polymerization of 2,4,6-trimethylpyridine, an aromatic monomer, a pyridyl modulator and a fluxing agent in a closed reactor to obtain a crude product;

[0010] purifying the crude product to obtain the pyridyl-doped vinyl porous organic polymer;

[0011] wherein the aromatic monomer is an aromatic compound containing two aldehyde functional groups;

[0012] the pyridyl modulator is a methyl- or aldehyde-substituted pyridine or a methyl- or aldehyde-substituted pyridine derivative;

[0013] the fluxing agent is a compound containing an anhydride functional group, a compound containing an acid chloride functional group or a compound containing a carboxylic acid functional group.

[0014] Preferably, the aromatic monomer comprises any one of benzene or a derivative thereof, biphenyl or a derivative thereof, naphthalene or a derivative thereof, pyridine or a derivative thereof, bipyridine or a derivative thereof, anthracene or a derivative thereof, pyrazine or a derivative thereof or phenanthroline or a derivative thereof containing two aldehyde functional groups.

[0015] Further preferably, the aromatic monomer comprises any one of p-phthalaldehyde, m-phthalaldehyde or biphenylaldehyde.

[0016] Preferably, the pyridyl modulator comprises any one of 6-methyl-2-pyridine carboxylic acid, 2-trifluoromethyl-6-methylpyridine, 2-cyano-6-methylpyridine, 2-hydroxy-6-methylpyridine, 4-bromo-2,6-dimethylpyridine, 4-chloro-2,6-dimethylpyridine, 4-amino-2,6-dimethylpyridine, 4-hydroxy-2,6-dimethylpyridine, 4-carboxy-2,6-dimethylpyridine, 2,6-dimethyl-4-hydroxymethylpyridine, 2,6-dimethyl-4-pyridine carboxaldehyde, 2,3,5-trimethylpyridine, 2,3,6-trimethylpyridine, 6-bromo-2-pyridine carboxaldehyde, pyridine-2-carboxaldehyde, 6-hydroxymethylpyridine carboxaldehyde, 2-methylpyridine, 2,6-dimethylpyridine, 2-amino-6-methylpyridine, 2-bromo-6-methylpyridine, 2-chloro-6-methylpyridine, 2-methoxy-6-methylpyridine, 4-methylpyridine, 2,4-dimethylpyridine, 2-amino-4-methylpyridine, 2-hydroxy-4-methylpyridine or 2-amino-4,6-dimethylpyridine.

[0017] Preferably, the fluxing agent comprises at least one of benzoic anhydride, sodium benzoate, 4-methoxybenzoic anhydride, acetic anhydride, trifluoroacetic anhydride, benzoic acid, 4-fluorobenzoic acid, 4-hydroxybenzoic acid, acetic acid or propionic acid.

[0018] Preferably, the molar ratio of the pyridyl modulator, 2,4,6-trimethylpyridine, the aromatic monomer and the fluxing agent is 1:(0.5-10):(1.5-15):(4-30).

[0019] Preferably, the temperature of the melt polymerization reaction is 160-200℃, and the reaction time is 72-120h.

[0020] The pressure of the melt polymerization reaction is normal pressure or negative pressure.

[0021] Preferably, the purification specifically comprises:

[0022] The reaction product is soaked in DMF to remove unreacted monomers, Soxhlet extraction in methanol to remove excess fluxing agent, and then dried at 80-100℃.

[0023] In a second aspect of the present application, the pyridyl-doped vinyl porous organic polymer prepared by the above preparation method is provided.

[0024] In a third aspect of the present application, the pyridyl-doped vinyl porous organic polymer is applied to HF capture materials.

[0025] Compared with the prior art, the present application has the following beneficial effects:

[0026] The present application uses specific reaction monomers and fluxing agents to prepare pyridyl-doped vinyl porous organic polymers by melt polymerization, which has high surface area, high porosity and high stability, and can be recycled multiple times when used in the adsorption of HF acid in electrolyte, and has high application value and economic benefits.

[0027] The preparation process of the present application is simple, avoids the high temperature and high pressure phenomenon caused by the use of a large amount of organic solvent, and can realize large-scale industrial production. BRIEF DESCRIPTION OF DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments described in the present application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0029] Figure 1Infrared spectrum of 2,4,6-trimethylpyridine, p-xylylformaldehyde, 2,3,5-trimethylpyridine, and pyridyl-doped vinyl porous organic material NKPy-VPOM-1 of Example 1;

[0030] Figure 2 PXRD pattern of pyridyl-doped vinyl porous organic polymer NKPy-VPOM-1;

[0031] Figure 3 Nitrogen isotherm adsorption-desorption curve of pyridyl-doped vinyl porous organic material NKPy-VPOM-1 at 77 K;

[0032] Figure 4 Pore size distribution curve of pyridyl-doped vinyl porous organic material NKPy-VPOM-1;

[0033] Figure 5 Thermogravimetric curve of pyridyl-doped vinyl porous organic material NKPy-VPOM-1;

[0034] Figure 6 Infrared spectrum of 2,4,6-trimethylpyridine, p-xylylformaldehyde, 4-methylpyridine, and pyridyl-doped vinyl porous organic material NKPy-VPOM-4;

[0035] Figure 7 PXRD pattern of pyridyl-doped vinyl porous organic polymer NKPy-VPOM-4;

[0036] Figure 8 Nitrogen isotherm adsorption-desorption curve of pyridyl-doped vinyl porous organic material NKPy-VPOM-4 at 77 K;

[0037] Figure 9 Pore size distribution curve of pyridyl-doped vinyl porous organic material NKPy-VPOM-4;

[0038] Figure 10 Thermogravimetric curve of pyridyl-doped vinyl porous organic material NKPy-VPOM-4;

[0039] Figure 11 Pyridyl-doped vinyl porous organic material HF adsorption performance test chart;

[0040] Figure 12 Pyridyl-doped vinyl porous organic material NKPy-VPOM-1 HF cyclic adsorption performance chart. DETAILED DESCRIPTION

[0041] With reference to the drawings and the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described. Obviously, the described embodiments are some of the embodiments of the present application, but not all the embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of the present application.

[0042] In the following description of the embodiments of the present application, the terms "comprising", "containing", "having" and "including" and the like are open-ended terms, i.e., meaning "including, but not limited to".

[0043] In the following description of the embodiments of the present application, the term "and / or" is used to describe the association relationship of the associated objects, which means that there can be three kinds of relationships, for example, A and / or B, which can represent the cases of A alone, B alone and A and B existing at the same time. Wherein A and B can be singular or plural. The character " / " generally represents an "or" relationship between the front and rear associated objects.

[0044] In the following description of the embodiments of the present application, the term "at least one" means one or more, and "multiple" means two or more. "At least one of the following (one)" or the like means any combination of these items, including any combination of single (one) or multiple items. For example, "at least one of a, b or c", or "at least one of a, b and c", can represent a, b, c, a-b (i.e., a and b), a-c, b-c, or a-b-c, wherein a, b, and c can be single or multiple.

[0045] The terms used in the embodiments of the present application are merely for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "a" and "the" used in the embodiments of the present application and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise.

[0046] Those skilled in the art should understand that in the following description of the embodiments of the present application, the order of the serial numbers does not mean the order of execution, and some or all steps can be executed in parallel or in sequence, and the execution order of each process should be determined according to its function and inherent logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0047] Those skilled in the art should understand that the numerical ranges in the embodiments of the present application should be understood as each intermediate value between the upper limit and the lower limit of the range. Each smaller range between any stated value or stated range and any other stated value or intermediate value within the stated range is also included in the present application. The upper limit and the lower limit of these smaller ranges can be independently included or excluded from the range.

[0048] Unless otherwise indicated, the technical / scientific terms used herein have the same meaning as is commonly understood by one of ordinary skill in the art to which this application belongs. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present application, the preferred methods and materials are described. All documents mentioned herein are incorporated by reference to disclose and describe in full the methods and / or materials which are described therein. In case of conflict, the content of the present specification will control.

[0049] In a first aspect, the present application provides a method for preparing a pyridine-doped vinyl porous organic polymer, comprising:

[0050] melting polymerization of 2,4,6-trimethylpyridine, an aromatic monomer, a pyridine modulator and a fluxing agent in a closed reactor to obtain a crude product;

[0051] purifying the crude product to obtain the pyridine-doped vinyl porous organic polymer.

[0052] Specifically, the present application adds 2,4,6-trimethylpyridine, an aromatic monomer, a pyridine modulator and a fluxing agent into a closed reactor, such as a high-temperature and high-pressure resistant Pyrex tube, a flame-sealed ampoule or a high-pressure reactor with a polytetrafluoroethylene liner, to carry out a melting polymerization reaction to obtain a crude product of the pyridine-doped vinyl porous organic polymer. The crude product is soaked in DMF to remove unreacted monomers, then subjected to Soxhlet extraction in methanol to remove excess fluxing agent, and then dried in an oven at 80-100°C to obtain a pyridine-doped vinyl porous organic polymer in the form of powder or block.

[0053] Preferably, the molar ratio of the pyridine modulator, 2,4,6-trimethylpyridine, the aromatic monomer and the fluxing agent is 1:(0.5-10):(1.5-15):(4-30) in the melting polymerization reaction. The melting polymerization reaction is carried out at a temperature of 160-200°C for 72-120 hours under normal pressure or negative pressure, preferably under negative pressure. More preferably, the molar ratio of the pyridine modulator, 2,4,6-trimethylpyridine, the aromatic monomer and the fluxing agent is 1:(1-9):(2-15):(5-30).

[0054] In the present application, the aromatic monomer is an aromatic compound containing two aldehyde functional groups; preferably, benzene or its derivatives containing two aldehyde functional groups, biphenyl or its derivatives containing two aldehyde functional groups, naphthalene or its derivatives containing two aldehyde functional groups, pyridine or its derivatives containing two aldehyde functional groups, bipyridine or its derivatives containing two aldehyde functional groups, anthracene or its derivatives containing two aldehyde functional groups, pyrazine or its derivatives containing two aldehyde functional groups, or phenanthroline or its derivatives containing two aldehyde functional groups; particularly preferably, benzene or its derivatives containing two aldehyde functional groups, such as any one of terephthalaldehyde, isophthalaldehyde or biphenyldicarboxaldehyde.

[0055] In the present application, the pyridine-based modulator is a methyl or aldehyde-substituted pyridine, or a methyl or aldehyde-substituted pyridine derivative, preferably 6-methyl-2-pyridinecarboxylic acid, 2-trifluoromethyl-6-methylpyridine, 2-cyano-6-methylpyridine, 2-hydroxy-6-methylpyridine, 4-bromo-2,6-dimethylpyridine, 4-chloro-2,6-dimethylpyridine, 4-amino-2,6-dimethylpyridine, 4-hydroxy-2,6-dimethylpyridine, 4-carboxyl-2,6-dimethylpyridine, 2,6-dimethyl-4-hydroxymethylpyridine, 2,6-dimethyl any one of 6-methyl-4-pyridinecarboxaldehyde, 2,3,5-trimethylpyridine, 2,3,6-trimethylpyridine, 6-bromo-2-pyridinecarboxaldehyde, pyridine-2-carboxaldehyde, 6-hydroxymethylpyridinecarboxaldehyde, 2-methylpyridine, 2,6-dimethylpyridine, 2-amino-6-methylpyridine, 2-bromo-6-methylpyridine, 2-chloro-6-methylpyridine, 2-methoxy-6-methylpyridine, 4-methylpyridine, 2,4-dimethylpyridine, 2-amino-4-methylpyridine, 2-hydroxy-4-methylpyridine or 2-amino-4,6-dimethylpyridine.

[0056] In the present application, the flux is used to promote the polymerization reaction of the methyl group in 2,4,6-trimethylpyridine, the methyl / aldehyde group in the pyridyl modulator, and the aldehyde group in the aromatic monomer to form a carbon-carbon double bond, thereby obtaining a pyridyl-doped vinyl porous organic polymer. The flux is a compound containing an anhydride functional group, a compound containing an acyl chloride functional group, or a compound containing a carboxylic acid functional group, preferably at least one of benzoic anhydride, sodium benzoate, 4-methoxybenzoic anhydride, acetic anhydride, trifluoroacetic anhydride, benzoic acid, 4-fluorobenzoic acid, 4-hydroxybenzoic acid, acetic acid, or propionic acid.

[0057] The preparation method of the present application has a simple process, avoids the high temperature and high pressure phenomena caused by the use of a large amount of organic solvents, and can realize large-scale industrial production.

[0058] The application prepares a pyridyl-doped vinyl porous organic polymer by a melt polymerization method with specific reaction monomers and fluxing agents, which has a high surface area, high porosity and high stability, a pore size of 1.8 nm to 7.0 nm, and pyridyl basic sites and more action sites with HF acid. The pyridyl-doped vinyl porous organic polymer can be used for capturing HF in an electrolyte, realizing accurate management of HF in the electrolyte, solving the safety hazard of the battery system, and being recycled multiple times, and has important application value.

[0059] The pyridyl-doped vinyl porous organic polymer of the application can be used as an HF capturing material or for preparing an HF capturing material, has high stability, can be reused after desorption treatment after adsorption, has renewability, greatly reduces the cost, has very high application value and economic benefits.

[0060] The application is further described below through examples.

[0061] Example 1

[0062] The example provides a preparation method of a pyridyl-doped vinyl porous organic polymer, comprising:

[0063] 0.71 mmol of 2,4,6-trimethylpyridine, 1.2 mmol of p-xylylene glycol, 0.08 mmol of 2,3,5-trimethylpyridine, and 2.4 mmol of acetic anhydride are loaded into a high-temperature and high-pressure thick-walled glass tube, the glass tube is sealed by a flame generated by a hydrogen-oxygen machine to isolate the internal and external systems. The sealed glass tube is reacted in an oven at 180°C for 5 days to obtain a red block-shaped solid. After soaking in DMF, the solid is Soxhlet extracted in methanol for 24 h, and then dried at 80°C to obtain an orange powder-shaped material with a yield of about 96%, which is denoted as NKPy-VPOM-1.

[0064] Example 2

[0065] The example provides a preparation method of a pyridyl-doped vinyl porous organic polymer, comprising:

[0066] 0.65 mmol of 2,4,6-trimethylpyridine, 1.2 mmol of p-xylylene glycol, 0.17 mmol of 2,3,5-trimethylpyridine, and 4.8 mmol of 4-methoxybenzoic anhydride are loaded into a high-temperature and high-pressure thick-walled glass tube, the glass tube is sealed by a flame generated by a hydrogen-oxygen machine to isolate the internal and external systems. The sealed glass tube is reacted in an oven at 180°C for 5 days to obtain a red block-shaped solid. After soaking in DMF, the solid is Soxhlet extracted in methanol for 24 h, and then dried at 80°C to obtain an orange powder-shaped material with a yield of about 90%, which is denoted as NKPy-VPOM-2.

[0067] Example 3

[0068] This example provides a method of preparing a pyridyl-doped vinyl porous organic polymer, comprising:

[0069] A high temperature and pressure resistant thick-walled glass tube was charged with 0.56 mmol of 2,4,6-trimethylpyridine, 1.2 mmol of p-xylylene glycol, 0.24 mmol of 2,3,5-trimethylpyridine, and 4.8 mmol of acetic acid, and the glass tube was sealed by a flame generated by a hydrogen-oxygen machine to isolate the internal and external systems. The sealed glass tube was reacted in an oven at 180 °C for 5 days to obtain a red block solid. After soaking in DMF, it was Soxhlet extracted in methanol for 12 h, and then dried at 80 °C to obtain an orange powdery material with a yield of about 89%, which is denoted as NKPy-VPOM-3.

[0070] The polymerization reactions in Examples 1-3 are shown below:

[0071]

[0072] Example 4

[0073] This example provides a method of preparing a pyridyl-doped vinyl porous organic polymer, comprising:

[0074] A high temperature and pressure resistant thick-walled glass tube was charged with 0.72 mmol of 2,4,6-trimethylpyridine, 1.2 mmol of p-xylylene glycol, 0.24 mmol of 4-methylpyridine, and 2.4 mmol of acetic anhydride, and the glass tube was sealed by a flame generated by a hydrogen-oxygen machine to isolate the internal and external systems. The sealed glass tube was reacted in an oven at 180 °C for 5 days to obtain a red block solid. After soaking in DMF, it was Soxhlet extracted in methanol for 12 h, and then dried at 100 °C to obtain an orange powdery material with a yield of about 95%, which is denoted as NKPy-VPOM-4.

[0075] Example 5

[0076] This example provides a method of preparing a pyridyl-doped vinyl porous organic polymer, comprising:

[0077] Into a high temperature and pressure resistant thick-walled glass tube, 0.64 mmol of 2,4,6-trimethylpyridine, 1.2 mmol of p-xylylene dichalide, 0.48 mmol of 4-methylpyridine, and 2.4 mmol of 4-fluorobenzoic acid were charged, and the glass tube was sealed by a flame generated by a hydrogen-oxygen machine to isolate the inside and outside systems. The sealed glass tube was reacted in an oven at 180 °C for 5 days to obtain a red block solid. After soaking in DMF, it was Soxhlet extracted in methanol for 48 h, and then dried at 100 °C to obtain a yellow powdery material with a yield of about 93%, which is recorded as NKPy-VPOM-5.

[0078] Example 6

[0079] The present example provides a method for preparing a pyridyl-doped vinyl porous organic polymer, comprising:

[0080] Into a high temperature and pressure resistant thick-walled glass tube, 0.56 mmol of 2,4,6-trimethylpyridine, 1.2 mmol of p-xylylene dichalide, 0.72 mmol of 4-methylpyridine, and 4 mmol of 4-hydroxybenzoic acid were charged, and the glass tube was sealed by a flame generated by a hydrogen-oxygen machine to isolate the inside and outside systems. The sealed glass tube was reacted in an oven at 200 °C for 5 days to obtain a red-brown block solid. After soaking in DMF, it was Soxhlet extracted in methanol for 12 h, and then dried at 100 °C to obtain an orange powdery material with a yield of about 88%, which is recorded as NKPy-VPOM-6.

[0081] The polymerization reactions in Examples 4-6 are shown as follows:

[0082]

[0083] Example 7

[0084] The present example provides a method for preparing a pyridyl-doped vinyl porous organic polymer, comprising:

[0085] Into a high temperature and pressure resistant thick-walled glass tube, 0.72 mmol of 2,4,6-trimethylpyridine, 1.2 mmol of p-xylylene dichalide, 0.12 mmol of 4-hydroxy-2,6-dimethylpyridine, and 2.4 mmol of acetic anhydride were charged, and the glass tube was sealed by a flame generated by a hydrogen-oxygen machine to isolate the inside and outside systems. The sealed glass tube was reacted in an oven at 200 °C for 5 days to obtain a red-brown block solid. After soaking in DMF, it was Soxhlet extracted in methanol for 24 h, and then dried at 100 °C to obtain a yellow powdery material with a yield of about 93%, which is recorded as NKPy-VPOM-7.

[0086] Example 8

[0087] This embodiment provides a method for preparing a pyridine-doped vinyl porous organic polymer, comprising:

[0088] 0.68 mmol of 2,4,6-trimethylpyridine, 1.2 mmol of terephthalaldehyde, 0.18 mmol of 4-hydroxy-2,6-dimethylpyridine, and 4.8 mmol of acetic acid were placed in a high-temperature, high-pressure, thick-walled glass tube. The tube was sealed with a flame generated by an oxyhydrogen generator to isolate the internal and external systems. The sealed glass tube was reacted in an oven at 200°C for 5 days to obtain a reddish-brown blocky solid. After soaking it in DMF, Soxhlet extraction was carried out in methanol for 12 hours, and then drying at 100°C to obtain an orange powder with a yield of approximately 89%, which was recorded as NKPy-VPOM-8.

[0089] The polymerization reactions in Examples 7-8 are as follows:

[0090]

[0091] Comparative Example 1

[0092] Existing organic amine HF adsorption materials include triethanolamine, ethylenediamine and polyethyleneimine

[0093] The pyridyl-doped vinyl porous organic polymer NKPy-VPOM-1 prepared in Example 1 and the pyridyl-doped vinyl porous organic polymer NKPy-VPOM-4 prepared in Example 4 were characterized and their performance was evaluated.

[0094] Figure 1 The infrared spectrum test results of 2,4,6-trimethylpyridine, terephthalaldehyde, 2,3,5-trimethylpyridine and NKPy-VPOM-1 in Example 1 are shown in FIG. Figure 1 It can be seen that NKPy-VPOM-1 has a peak at 1629 cm -1 The peak corresponding to the stretching vibration of the carbon-carbon double bond indicates that it is a vinyl connection.

[0095] Figure 2 is the PXRD pattern of NKPy-VPOM-1. Figure 2 It can be seen that it has good crystallinity, and good crystallinity gives it a higher specific surface area and a suitable pore structure, which gives it a better HF acid adsorption capacity.

[0096] Figure 3 is the nitrogen isothermal adsorption-desorption curve of NKPy-VPOM-1 at 77K. Figure 3 It can be concluded that its BET surface area is 746.8m 2 / g, with high surface area.

[0097] Figure 4is the pore size distribution curve of NKPy-VPOM-1, from Figure 4 It can be seen that the pore diameters are 1.8 nm and 3.3 nm, which means that the material is a micro-mesoporous material with high porosity.

[0098] The thermal stability of NKPy-VPOM-1 of Example 1 was tested by TGA analyzer, and its thermogravimetric diagram is shown in FIG. Figure 5 As shown. Figure 5 It can be seen that NKPy-VPOM-1 does not undergo obvious structural collapse before 500°C, and it has excellent structural stability.

[0099] Figure 6 The infrared spectrum test results of 2,4,6-trimethylpyridine, terephthalaldehyde, 4-methylpyridine and NKPy-VPOM-4 in Example 4 are shown in FIG. Figure 6 It can be seen that NKPy-VPOM-4 has a peak at 1630 cm -1 The peak corresponding to the stretching vibration of the carbon-carbon double bond indicates that it is a vinyl bond.

[0100] Figure 7 is the PXRD pattern of NKPy-VPOM-4. Figure 7 It can be seen that it has good crystallinity, and good crystallinity gives it a higher specific surface area and a suitable pore structure, which gives it a better HF acid adsorption capacity.

[0101] Figure 8 is the nitrogen isothermal adsorption-desorption curve of NKPy-VPOM-4 at 77K. Figure 8 It can be concluded that its BET surface area is 542.04m 2 / g, the hysteresis loop of the curve proves the existence of mesopores in the material.

[0102] Figure 9 is the pore size distribution curve of NKPy-VPOM-4, from Figure 9 It can be seen that it has a multi-level pore structure, and its pore diameter is roughly distributed between 1.9-4nm. It is a micro-mesoporous material with high porosity.

[0103] The thermal stability of NKPy-VPOM-4 was tested by TGA analyzer, and its thermogravimetric diagram is shown in Figure 10 As shown. Figure 10 It can be seen that NKPy-VPOM-4 does not undergo obvious structural collapse before 500°C, and it has excellent structural stability.

[0104] The HF performance of the pyridine-doped vinyl porous organic materials NKPy-VPOM-1 to NKPy-VPOM-5 prepared in Examples 1-5 was tested in a 0.5% HF dimethyl carbonate solution (simulated electrolyte) as follows:

[0105] 100 mg of the above materials were placed in 0.5% HF acid dimethyl carbonate solution and stirred overnight for static adsorption. An appropriate amount of the solution was taken to determine its adsorption capacity for HF acid by potentiometric titration. The adsorption test results are shown in Figure 2. Figure 11 As shown. Figure 11 It can be seen that the pyridine-doped vinyl porous organic materials prepared in Examples 1-5 all have good HF adsorption performance.

[0106] The adsorbed NKPy-VPOM-1 was washed from top to bottom with 0.1M NaOH ethanol solution until the washing solution was neutral, completing the desorption. The desorbed NKPy-VPOM-1 was subjected to HF acid static adsorption again, and then desorbed again after adsorption, and a cycle experiment was performed. The results of the cycle experiment are shown in Figure 2. Figure 12 As shown. Figure 12 It can be seen that after 5 cycles, the adsorption performance of NKPy-VPOM-1 has hardly decreased, and its adsorption performance has not changed after multiple cycles, which proves that the material has good regeneration performance.

[0107] The triethanolamine of comparative example 1 and ethylenediamine are easily protonated or decomposition reaction occurs under acidic conditions, and especially under high concentration HF or hot condition, its molecular skeleton may be destroyed, causes material property decay, recycles.In addition, part amine molecule is low molecular weight liquid or is soluble in polar solvent, and immobilization difficulty, easily oozes out or runs off, poor stability, is difficult to cycle test. Polyethyleneimine (PEI) class material, owing to being rich in amido, can be combined with HF acid by physical adsorption or weak chemical action, possesses certain regeneration capacity.But the reversibility of its adsorption-desorption process is relatively poor, and it is easy to occur phenomena such as active site loss, structure local degradation or amido irreversible passivation in it in recycle, causes adsorption capacity progressively to decline.

[0108] Although this specification has been used to fully describe the present application using general descriptions and specific embodiments, it is obvious to those skilled in the art that modifications or improvements may be made based on the present application. Therefore, such modifications or improvements made without departing from the spirit of the present application are within the scope of protection claimed in this application.

Claims

1. A method for preparing a pyridine-doped vinyl porous organic polymer, characterized in that: include: 2,4,6-trimethylpyridine, an aromatic monomer, a pyridine-based modulator, and a flux are melt-polymerized in a closed reactor to obtain a crude product; Purifying the crude product to obtain a pyridine-doped vinyl porous organic polymer; Wherein, the aromatic monomer is an aromatic compound containing two aldehyde functional groups; The pyridyl modulator is a methyl- or aldehyde-substituted pyridine, or a methyl- or aldehyde-substituted pyridine derivative; The flux is a compound containing an anhydride functional group, a compound containing an acyl chloride functional group or a compound containing a carboxylic acid functional group.

2. The preparation method according to claim 1, characterized in that The aromatic monomer includes any one of benzene or its derivatives, biphenyl or its derivatives, naphthalene or its derivatives, pyridine or its derivatives, bipyridine or its derivatives, anthracene or its derivatives, pyrazine or its derivatives, or phenanthroline or its derivatives containing two aldehyde functional groups.

3. The preparation method according to claim 2, characterized in that The aromatic monomer includes any one of terephthalaldehyde, isophthalaldehyde or biphenyldicarboxaldehyde.

4. The preparation method according to claim 1, characterized in that The pyridine-based modulators include 6-methyl-2-pyridinecarboxylic acid, 2-trifluoromethyl-6-methylpyridine, 2-cyano-6-methylpyridine, 2-hydroxy-6-methylpyridine, 4-bromo-2,6-dimethylpyridine, 4-chloro-2,6-dimethylpyridine, 4-amino-2,6-dimethylpyridine, 4-hydroxy-2,6-dimethylpyridine, 4-carboxyl-2,6-dimethylpyridine, 2,6-dimethyl-4-hydroxymethylpyridine, 2,6-dimethyl-4-pyridinecarboxaldehyde, 2,3,5-trimethylpyridine, any one of pyridine, 2,3,6-trimethylpyridine, 6-bromo-2-pyridinecarboxaldehyde, pyridine-2-carboxaldehyde, 6-hydroxymethylpyridinecarboxaldehyde, 2-methylpyridine, 2,6-lutidine, 2-amino-6-methylpyridine, 2-bromo-6-methylpyridine, 2-chloro-6-methylpyridine, 2-methoxy-6-methylpyridine, 4-methylpyridine, 2,4-lutidine, 2-amino-4-methylpyridine, 2-hydroxy-4-methylpyridine or 2-amino-4,6-lutidine.

5. The preparation method according to claim 1, characterized in that The flux includes at least one of benzoic anhydride, sodium benzoate, 4-methoxybenzoic anhydride, acetic anhydride, trifluoroacetic anhydride, benzoic acid, 4-fluorobenzoic acid, 4-hydroxybenzoic acid, acetic acid or propionic acid.

6. The preparation method according to claim 1, characterized in that The molar ratio of the pyridine-based modulator, 2,4,6-trimethylpyridine, the aromatic monomer and the flux is 1:(0.5-10):(1.5-15):(4-30).

7. The preparation method according to claim 1, characterized in that The temperature of the melt polymerization reaction is 160-200°C, and the reaction time is 72-120h; The pressure of the melt polymerization reaction is normal pressure or negative pressure.

8. The preparation method according to claim 1, characterized in that The purification specifically comprises: The reaction product was soaked in DMF to remove unreacted monomers, subjected to Soxhlet extraction in methanol to remove excess flux, and then dried at 80-100°C.

9. A pyridine-doped vinyl porous organic polymer prepared by the preparation method according to any one of claims 1 to 8.

10. Use of the pyridyl-doped vinyl porous organic polymer according to claim 9 in HF capture materials.

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