Cyclocarbazolyl porous polymer and preparation method and application thereof

Abstract

The invention provides a cup carbazolyl porous polymer as well as a preparation method and application thereof, and belongs to the field of organic polymer materials. The carbazolyl porous polymer has the advantages of hierarchical pore structure, large specific surface area, good stability, simple polymerization process and the like, and can be used in the fields of volatile organic pollutant adsorption, sewage treatment and the like.

Description

Technical Field

[0001] The invention relates to the field of organic polymer materials, and in particular to a calixcarbazole-based porous polymer and a preparation method and application thereof. Background Art

[0002] Volatile organic compounds (VOCs) generated by industrial processes and human activities are the main cause of air pollution. VOCs include a variety of chemicals, such as aromatic hydrocarbons, alcohols, ketones, and halogenated compounds. Many of these VOCs are not easily degradable and pose significant risks to human health and the environment. Therefore, air treatment solutions targeting VOCs are gaining more and more attention from industry and academia.

[0003] Currently, a variety of technologies have been used to control and treat VOCs, including catalytic oxidation, biofiltration, condensation and adsorption. Among them, adsorption technology is widely used due to its advantages of low cost, simple operation, high efficiency and environmental friendliness. However, the removal effect of traditional adsorbent materials such as activated carbon and zeolite is poor. Compared with these materials, porous organic polymers (POPs) are excellent candidates for potential VOCs adsorption due to their inherent advantages, including high porosity, controllable pore size and easy functionalization.

[0004] Due to the host-guest chemistry, incorporating macrocyclic receptors into POP networks is an effective strategy to improve their adsorption performance. Currently, crown ethers, calixarene, resorcinol calixarene, pillararene, and calix[4]pyrrole have been successfully incorporated into POP networks and have shown effectiveness in wastewater adsorption treatment. However, macrocyclic POPs have not yet been used for VOCs adsorption treatment. Therefore, it is of great significance to design and synthesize a macrocyclic POP adsorbent for VOCs treatment. Summary of the invention

[0005] The invention provides a calixcarbazolyl porous polymer and a preparation method and application thereof. The calixcarbazolyl porous polymer has high stability and excellent VOCs adsorption capacity.

[0006] The present invention provides a cup-carbazole-based porous polymer having a structural formula shown in Formula I:

[0007]

[0008] Preferably, the BET specific surface area of ​​the cup-carbazole-based porous polymer is 750 to 1000 m 2 ·g -1 .

[0009] Preferably, the method comprises the following steps:

[0010] The compound of formula II, the compound of formula III, an inorganic base and an organic solvent are mixed to carry out a nucleophilic substitution reaction to obtain the calixcarbazole-based porous polymer;

[0011]

[0012] Preferably, the molar ratio of the compound of the structural formula represented by formula II to the compound of the structural formula represented by formula III is 1:1.5.

[0013] Preferably, the inorganic base comprises one or more of potassium carbonate, sodium carbonate, cesium carbonate, potassium bicarbonate and sodium bicarbonate.

[0014] Preferably, the molar ratio of the compound of the structural formula represented by formula II to the inorganic base is 1:6-15.

[0015] Preferably, the organic solvent includes one or more of tetrahydrofuran, N-methylpyrrolidone, dimethyl sulfoxide, 1,4-dioxane, N,N-dimethylformamide and N,N-dimethylacetamide.

[0016] Preferably, the solid-to-liquid ratio of the compound of the structural formula represented by Formula II to the organic solvent is 50-100 mg:1 mL.

[0017] Preferably, the temperature of the nucleophilic substitution reaction is 80-200° C. and the time is 1-48 h.

[0018] The present invention also provides the use of the calixcarbazole-based porous polymer described in the above technical solution or the calixcarbazole-based porous polymer prepared by the preparation method described in the above technical solution in adsorbing VOCs or treating sewage.

[0019] The carbazole-based porous polymer of the present invention has the advantages of multi-level pore structure, large specific surface area, good stability, simple polymerization process, etc. The multi-level pore structure can reduce mass transfer resistance, which is conducive to the entry of pollutant molecules into the cavity. The large specific surface area can provide sufficient adsorption space. The carbazole macrocycle as a strong adsorption site brings excellent adsorption performance to the polymer, and the high stability is conducive to the practical use of the polymer. Therefore, the carbazole-based porous polymer of the present invention can be used in the fields of volatile organic pollutant adsorption and sewage treatment. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The cross polarization / magic angle spin of the carbazole-based porous polymer prepared in Example 1 13 C NMR spectrum;

[0021] Figure 2 is the infrared analysis spectrum of the carbazole-based porous polymer prepared in Example 1;

[0022] Figure 3Thermogravimetric analysis spectrum of the carbazole-based porous polymer prepared in Example 1;

[0023] Figure 4 is a nitrogen adsorption-desorption isotherm diagram of the carbazole-based porous polymer prepared in Example 1 at 77K;

[0024] Figure 5 is a pore size distribution diagram of the carbazole-based porous polymer prepared in Example 1;

[0025] Figure 6 is a scanning electron microscope image of the carbazole-based porous polymer prepared in Example 1;

[0026] Figure 7 This is a graph showing the VOCs adsorption amount of the carbazole-based porous polymer prepared in Example 1. DETAILED DESCRIPTION

[0027] The present invention provides a cup-carbazole-based porous polymer having a structural formula shown in Formula I;

[0028]

[0029] In the present invention, the BET specific surface area of ​​the cup-carbazole-based porous polymer is preferably 836 to 883 m 2 ·g -1 .

[0030] The wavy lines in Formula I represent repeating units.

[0031] In the present invention, the BET specific surface area of ​​the cup-carbazole-based porous polymer is preferably 750 to 1000 m 2 ·g -1 .

[0032] The present invention provides a method for preparing the cupcarbazole-based porous polymer described in the above technical solution, comprising the following steps:

[0033] The compound of formula II, the compound of formula III, an inorganic base and an organic solvent are mixed to carry out a nucleophilic substitution reaction to obtain the calixcarbazole-based porous polymer;

[0034]

[0035] In the present invention, the mixing preferably comprises: mixing the compound of formula II, the compound of formula III and an organic solvent, and then mixing the obtained mixture with an inorganic base under a protective atmosphere.

[0036] In the present invention, the molar ratio of the compound of the structural formula shown in formula II to the compound of the structural formula shown in formula III is preferably 1:1-3. In a specific embodiment of the present invention, the molar ratio of the compound of the structural formula shown in formula II to the compound of the structural formula shown in formula III can be 1:1, 1:1.5, 1:2, 1:2.5 or 1:3.

[0037] In the present invention, the molar ratio of the compound of the structural formula shown in Formula II to the inorganic base is preferably 1:6-15. In a specific embodiment of the present invention, the molar ratio of the compound of the structural formula shown in Formula II to the inorganic base can be 1:6, 1:7, 1:8, 1:9, 1:10, 1:11, 1:12, 1:13, 1:14 or 1:15; the inorganic base preferably includes one or more of potassium carbonate, sodium carbonate, cesium carbonate, potassium bicarbonate and sodium bicarbonate.

[0038] In the present invention, the solid-liquid ratio of the compound of the structural formula shown in Formula II to the organic solvent is preferably 50-100 mg:1 mL. In a specific embodiment of the present invention, the solid-liquid ratio of the compound of the structural formula shown in Formula II to the organic solvent can be 50 mg:1 mL, 60 mg:1 mL, 70 mg:1 mL, 80 mg:1 mL, 90 mg:1 mL or 100 mg:1 mL; the organic solvent preferably includes one or more of tetrahydrofuran, N-methylpyrrolidone, dimethyl sulfoxide, 1,4-dioxane, N,N-dimethylformamide and N,N-dimethylacetamide.

[0039] In the present invention, the temperature of the nucleophilic substitution reaction is preferably 80-200°C, and the time is preferably 1-48h; in a specific embodiment of the present invention, the temperature of the nucleophilic substitution reaction can be 80°C, 100°C, 120°C, 140°C, 160°C, 180°C or 200°C; the time of the nucleophilic substitution reaction can be 1h, 6h, 12h, 18h, 24h, 30h, 36h, 42h or 48h.

[0040] In the present invention, after the nucleophilic substitution reaction, the method preferably further comprises: performing solid-liquid separation on the product obtained by the nucleophilic substitution reaction, and then washing, Soxhlet extraction and drying the solid obtained by the solid-liquid separation.

[0041] In the present invention, the washing preferably includes a first deionized water washing, an acid solution washing and a second deionized water washing in sequence.

[0042] The present invention has no special limitation on the first deionized water washing, and conventional technical solutions can be used for washing until the washing liquid is colorless and there is no obvious white potassium carbonate solid in the crude product.

[0043] In the present invention, the acid solution used for the acid solution washing preferably includes hydrochloric acid, sulfuric acid, fluoroboric acid or acetic acid; the concentration of the acid solution is preferably 0.1-2M. In a specific embodiment of the present invention, the acid solution can be dilute hydrochloric acid with a concentration of 1M.

[0044] The present invention has no special limitation on the acid solution washing, and the inorganic alkali in the solid can be removed by using conventional technical solutions.

[0045] The present invention has no special limitation on the second deionized water washing, and conventional technical solutions can be used for washing until neutrality.

[0046] In the present invention, the reagent used for the Soxhlet extraction preferably includes methanol.

[0047] The present invention has no special limitation on Soxhlet extraction, and conventional technical solutions can be used to perform Soxhlet extraction until no polymer dissolution is left in the extract.

[0048] The present invention also provides the use of the calixcarbazole-based porous polymer described in the above technical solution or the calixcarbazole-based porous polymer prepared by the preparation method described in the above technical solution in adsorbing VOCs or treating sewage.

[0049] The cup-carbazole-based porous polymer provided by the present invention and its preparation method and application are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0050] Example 1

[0051] Dissolve cup[3]carbazole (250 mg, 0.290 mmol) and tetrafluoroterephthalonitrile (87 mg, 0.435 mmol) in 5 mL of anhydrous DMSO, and then add K2CO3 (601 mg, 4.35 mmol) under nitrogen protection. Quickly place the reaction bottle at 150 ° C for 6 hours. After the reaction is completed, wash the solid with deionized water. Then use 50 mL of dilute hydrochloric acid (1M) to fully wash away the alkali in the reaction system, then wash with deionized water, then use methanol Soxhlet extraction for 24 hours, and then vacuum dry at 80 ° C. The resulting polymer yield is 98% and the BET specific surface area is 836m 2 g -1 .

[0052] Figure 1 The cross polarization / magic angle spin of the carbazole-based porous polymer prepared in Example 1 13 C NMR spectrum.

[0053] Depend on Figure 1 It can be seen that the most obvious peak at 154 ppm is attributed to the CO bond, indicating that the polymer was successfully synthesized according to the set synthesis route.

[0054] Figure 2 This is the infrared analysis spectrum of the carbazole-based porous polymer prepared in Example 1.

[0055] Depend on Figure 2 It can be seen that 1233cm -1 The peak at is attributed to CO stretching vibration.

[0056] Figure 3 Thermogravimetric analysis spectrum of the carbazole-based porous polymer prepared in Example 1;

[0057] Depend on Figure 3 It can be seen that the polymer has almost no weight loss below 350°C, indicating that the polymer has high thermal stability.

[0058] Figure 4 This is a nitrogen adsorption-desorption isotherm diagram of the carbazole-based porous polymer prepared in Example 1 at 77K.

[0059] Depend on Figure 4 It can be seen that the polymer shows a type IV adsorption curve, and the specific surface area is calculated to be 836

[0060] m 2 / g.

[0061] Figure 5 This is the pore size distribution diagram of the carbazole-based porous polymer prepared in Example 1.

[0062] Depend on Figure 5 It can be seen that the polymer has abundant micropores. The micropore volume can be calculated to be 0.30 cm 3 / g, and the mesopore volume is 0.34cm 3 / g.

[0063] Figure 6 This is a scanning electron microscope image of the carbazole-based porous polymer prepared in Example 1.

[0064] Depend on Figure 6 It can be seen that the polymer is a fluffy mass.

[0065] Figure 7 This is a graph showing the VOCs adsorption amount of the carbazole-based porous polymer prepared in Example 1.

[0066] Depend on Figure 7 It can be seen that the polymer has good adsorption capacity for various volatile organic compounds (dichloromethane, chloroform, 1,2-dichloroethane, ethyl acetate, acetone, chlorobenzene, toluene, methanol, etc.), especially for dichloromethane and chloroform.

[0067] Example 2

[0068] Dissolve cup[3]carbazole (250 mg, 0.290 mmol) and 2,3,5,6-tetrafluoroisonicotinonitrile (77 mg, 0.435 mmol) in 5 mL of anhydrous DMSO, and then add K2CO3 (601 mg, 4.35 mmol) under nitrogen protection. Quickly place the reaction bottle at 150 ° C for 6 hours. After the reaction is completed, wash the solid with deionized water. Then use 50 mL of dilute hydrochloric acid (1M) to fully wash away the alkali in the reaction system, then wash with deionized water, then extract with methanol Soxhlet for 24 hours, and then dry in vacuo at 80 ° C. The yield of the obtained polymer is 99%, and the BET specific surface area is 883m 2 g -1 .

[0069] Application Example 1

[0070] Adsorption of volatile organic compounds (taking dichloromethane as an example)

[0071] After the polymer sample in Example 1 was vacuum degassed at 120°C, 50 mg of the sample was placed in a 10 mL small sample bottle, and 5 mL of dichloromethane was placed in another 10 mL small sample bottle. The two sample bottles were then placed in a 500 mL glass bottle, which was sealed and placed in a 30°C thermostat for 24 hours. The adsorption amount was calculated to be 1720 mg g based on the weight change of the sample before and after adsorption. -1 .

[0072] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A calixcarbazolyl porous polymer, characterized in that: It has the structural formula shown in Formula I:

2. The cupcarbazole-based porous polymer according to claim 1, characterized in that: The BET specific surface area of ​​the cup-carbazole-based porous polymer is 750 to 1000 m 2 ·g -1 .

3. The method for preparing the cupcarbazole-based porous polymer according to claim 1 or 2, characterized in that: The following steps are involved: The compound of formula II, the compound of formula III, an inorganic base and an organic solvent are mixed to carry out a nucleophilic substitution reaction to obtain the calixcarbazole-based porous polymer; 4. The preparation method according to claim 3, characterized in that: The molar ratio of the compound of the structural formula represented by formula II to the compound of the structural formula represented by formula III is 1:1-3.

5. The preparation method according to claim 3, characterized in that: The inorganic base includes one or more of potassium carbonate, sodium carbonate, cesium carbonate, potassium bicarbonate and sodium bicarbonate.

6. The preparation method according to claim 3 or 5, characterized in that: The molar ratio of the compound of the structural formula represented by formula II to the inorganic base is 1:6-15.

7. The preparation method according to claim 3, characterized in that: The organic solvent includes one or more of tetrahydrofuran, N-methylpyrrolidone, dimethyl sulfoxide, 1,4-dioxane, N,N-dimethylformamide and N,N-dimethylacetamide.

8. The preparation method according to claim 3 or 7, characterized in that: The solid-to-liquid ratio of the compound of the structural formula represented by formula II to the organic solvent is 50-100 mg:1 mL.

9. The preparation method according to claim 3, characterized in that: The temperature of the nucleophilic substitution reaction is 80-200° C., and the time is 1-48 hours.

10. Use of the calixcarbazole-based porous polymer according to claim 1 or 2 or the calixcarbazole-based porous polymer prepared by the preparation method according to any one of claims 3 to 9 in adsorption of VOCs or sewage treatment.

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