Supramolecular polymer porous material PTP3 and synthesis and application thereof

Abstract

The invention discloses a supramolecular polymer porous material PTP3, which is formed by crosslinking terphenyl macrocycle with a large cavity as a basis, and a complex polymer network structure is formed in a crosslinking mode. The terphenyl macrocyclic TP3 with a large cavity is changed into a supramolecular polymer porous material PTP3 with a larger specific surface area, so that the binding capacity to dye molecules is improved. The polymer porous material has abundant cavities and a net-shaped structure, and the cavities and the net-shaped structure simultaneously play a synergistic effect, so that when the supramolecular polymer porous material PTP3 adsorbs and removes multi-component dyes in water, the removal rate is higher, and the use amount of an adsorbent is smaller. The invention provides a new thought for a novel supramolecular adsorbent for removing dye in an aqueous solution.

Description

Technical Field

[0001] The invention relates to a supramolecular polymer porous material PTP3, and also relates to the synthesis of the supramolecular polymer porous material PTP3 and the application of removing dyes in water, belonging to the fields of chemical synthesis and wastewater treatment. Background Art

[0002] Fresh water is one of the most important natural resources in the world. However, with the continuous advancement of modern science and technology in recent years, the global production and use of chemicals, such as dyes, pharmaceuticals and pesticides, has increased. Most of the dyes are organic compounds with strong carcinogenic and mutagenic properties. Their random discharge will have adverse effects on water bodies, aquatic organisms, human health and the environment. Common water purification technologies include electrochemistry, photochemistry and sonochemistry, and adsorption, as a simple and efficient water treatment technology, is also widely used in the field of water treatment. Therefore, it is of far-reaching significance to develop functional materials that can effectively remove organic dyes from water bodies, especially supramolecular polymer materials with advantages such as good stability, strong recyclability and high removal rate, which have more advantages than traditional adsorbents.

[0003] Therefore, in order to improve the removal rate of dyes, the present invention uses a terphenyl macrocycle with a large cavity as the basis for cross-linking to form a supramolecular polymer porous material PTP3. The terphenyl macrocycle has a larger cavity and can accommodate larger dye molecules, and the electron-rich cavity of the terphenyl macrocycle has a strong affinity for cationic and electron-deficient neutral dyes. Therefore, the supramolecular polymer based on the terphenyl macrocycle can improve its adsorption capacity for dyes. And the supramolecular polymer porous material PTP3 also has a large electron-rich cavity and a network structure, and the synergistic effect between the two can further improve the binding capacity for the target object. Therefore, the present invention designs and discloses a synthesis of a supramolecular polymer porous material PTP3 based on a terphenyl macrocycle and its synergistic adsorption of multi-component dye molecules. Summary of the invention

[0004] The purpose of the present invention is to provide a supramolecular polymer porous material PTP3 based on terphenyl macrocycle; Another object of the present invention is to provide a method for synthesizing the supramolecular polymer porous material PTP3; Another object of the present invention is to provide an application of the supramolecular polymer porous material PTP3 for adsorbing and removing dyes in water.

[0005] 1. Supramolecular polymer porous materials and their synthesis The structural formula of supramolecular polymer porous material PTP3 is: .

[0006] The preparation method of the supramolecular polymer porous material PTP3 of the present invention comprises the following steps: (1) Synthesis of compound TP: p-dibromobenzene and 2,4-dimethoxyphenylboronic acid are used as substrates, 1,4-dioxane / water mixture is used as solvent, sodium carbonate and [1,1'-bis(diphenylphosphino)ferrocene] palladium dichloride are added, and the mixture is reacted at 100-105°C for 10-15h under nitrogen protection; after the reaction, 1,4-dioxane is dried at 60-70°C and extracted with dichloroethane; the combined organic phase is concentrated, and the residue is separated by column chromatography to obtain a white solid, which is compound TP. The molar ratio of p-dibromobenzene to 2,4-dimethoxyphenylboronic acid is 1:1-1:3 (preferably 1:2); in the 1,4-dioxane / water mixture, the volume ratio of 1,4-dioxane to water is 3:1-5:1 (preferably 4:1). The molar ratio of p-dibromobenzene to [1,1'-bis(diphenylphosphino)ferrocene]palladium dichloride is 18:1-22:1 (preferably 20:1); the molar ratio of p-dibromobenzene to sodium carbonate is 1:1-1:3 (preferably 1:2).

[0007] (2) Synthesis of compound TP3: Compound TP and paraformaldehyde are used as substrates, 1,2-dichloroethane is used as solvent, and boron trifluoride ether is slowly added to react at room temperature for 1 to 3 hours; after the reaction is completed, the reaction solution is directly added to a saturated sodium bicarbonate solution to quench; the combined organic phase is concentrated after extraction and dried over anhydrous sodium sulfate; the residue is subjected to column chromatography to obtain a white solid, and the obtained product is compound TP3. The molar ratio of compound TP to paraformaldehyde is 1:1 to 1:2.

[0008] (3) Synthesis of compound OH-TP3: Using compound TP3 as substrate and dichloromethane as solvent, slowly add boron tribromide and react at room temperature for 45-50 hours. After the reaction, pipette the reaction solution into ice water to precipitate a white solid. Filter and rinse with dichloromethane to obtain compound OH-TP3.

[0009] Wherein, the molar ratio of compound TP3 to boron tribromide is 1:45-1:50 (preferably 1:48).

[0010] (4) Synthesis of compound PTP3: Compound OH-TP3 is used as a substrate, 1,2-dibromoethane is used as a cross-linking agent, acetonitrile is used as a solvent, triphenylphosphine is added, and the mixture is reacted at 70-80°C for 48 hours under nitrogen protection; after the reaction, an orange-red solid is precipitated, which is filtered and washed with water and methanol to obtain compound PTP3. The molar ratio of compound OH-TP3 to 1,2-dibromoethane is 1:8-1:10 (preferably 1:9); the molar ratio of compound OH-TP3 to triphenylphosphine is 1:3-1:5 (preferably 1:4).

[0011] The supramolecular polymer porous material prepared above is labeled as: PTP3, and its synthesis route is: .

[0012] The infrared spectra and high temperature gel permeation chromatography of compound OH-TP3 and compound PTP3 are shown in Figure 1 and Figure 2 By comparing the FT-IR spectra of PTP3 and its raw material OH-TP3 ( Figure 1 )It can be seen that: at 1300 and 699cm −1 The stretching vibration characteristic peaks of Ph-O-C and C-Br were shown nearby, indicating that the cross-linking reaction was successful and the compound PTP3 was successfully synthesized. In addition, the molecular weight of PTP3 was measured by high temperature gel permeation chromatography to be about 10 6 g / mol, which is about 1000 times larger than the molecular weight of its raw material OH-TP3, proving the successful polymerization of PTP3.

[0013] The nitrogen adsorption-desorption curve of compound OH-TP3 is shown in Figure 3 The nitrogen adsorption-desorption curve of compound PTP3 is shown in Figure 4 Through N2 adsorption-desorption experiments at 77 K, it was found that the specific surface areas of the raw material OH-TP3 and the polymer PTP3 were 20.4100 and 461 42.4821 m 2 ·g −1 The specific surface area of ​​polymer PTP3 is expanded to about twice that of the raw material. It can be seen that the polymer network structure increases the specific surface area of ​​polymer PTP3.

[0014] 2. Application of supramolecular polymer porous material PTP3 in removing dyes from water 1. Performance of supramolecular polymer porous material PTP3 in removing dyes from water The supramolecular polymer porous material PTP3 is insoluble in common solutions such as dimethyl sulfoxide, water, dichloromethane, petroleum ether, methanol, and ethanol, so it can be used to remove dyes in water. We selected typical anionic and cationic dyes, methyl green (MG), rhodamine B (RhB), methyl orange (MO), and acid chrome blue K (AK), with the structural formula shown in Figure 5 , and then the adsorption experiments of anionic and cationic dyes were carried out. The study on the performance of supramolecular polymer porous material PTP3 in removing dyes from water showed that supramolecular polymer porous material PTP3 has a synergistic effect in the adsorption and removal of multi-component dyes, and can remove dyes more quickly than single-component dyes ( Figure 6 ).

[0015] Inspired by the synergistic effect of supramolecular polymer porous material PTP3 in the adsorption and removal of multi-component dyes, we verify the synergistic effect of supramolecular polymer porous material PTP3 from another perspective. We will test the amount of adsorbent used for typical cationic dyes methyl green, rhodamine B and their mixed dyes. The results of the experiment using the controlled variable method showed that: 0.3 mg of supramolecular polymer porous material PTP3 is required to adsorb the same amount of methyl green; 30.3 mg of supramolecular polymer porous material PTP3 is also required to adsorb the same amount of rhodamine B; and only 0.2 mg of supramolecular polymer porous material PTP3 is required to adsorb the same amount of methyl green and rhodamine B mixed dyes ( Figure 7 ). We have once again demonstrated from the perspective of adsorbent dosage that the supramolecular polymer porous material PTP3 has a synergistic effect on the adsorption and removal of multi-component dyes.

[0016] 2. Recycling of supramolecular polymer porous material PTP3 The reusability and recyclability of the adsorbent are also important factors in evaluating the adsorption capacity of the adsorbent. Taking rhodamine B as a model pollutant, the used supramolecular polymer porous material PTP3 was soaked in a hydrochloric acid / ethanol mixture as a solvent, and desorption was achieved after centrifugation, washing, and freeze drying. The desorption process is simple and Figure 8 As shown, the UV-visible spectrum of the supramolecular polymer porous material PTP3 for rhodamine B is almost the same in each cycle, and the removal rate does not change significantly after five cycles, which indicates that the supramolecular polymer porous material PTP3 has good reusability and recyclability. In addition, Figure 8 In a, the UV-visible spectrum of the supramolecular polymer porous material PTP3 after five cycles did not change significantly compared with the original adsorbent, further proving the stability of the supramolecular polymer porous material PTP3 in repeated use experiments.

[0017] In summary, the present invention forms a supramolecular polymer porous material PTP3 by cross-linking a terphenyl macrocycle with rich electrons and a large cavity, and forms a complex polymer network structure by cross-linking, so that the terphenyl macrocycle TP3, which already has a large cavity, becomes a supramolecular polymer porous material PTP3 with a larger specific surface area, and thereby improves the binding ability to dye molecules. Due to the rich cavities and mesh structure of the polymer porous material, the two play a synergistic role at the same time, so that the supramolecular polymer porous material PTP3 has a faster removal rate and a smaller amount of adsorbent when adsorbing and removing multi-component dyes in water. The present invention provides a new idea for a new supramolecular adsorbent for removing dyes in aqueous solutions. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1Infrared spectra of supramolecular polymer porous material PTP3 and compound OH-TP3; Figure 2 It is the gel permeation chromatogram of supramolecular polymer porous material PTP3 and compound OH-TP3; Figure 3 is the nitrogen adsorption-desorption curve of compound TP3; Figure 4 It is a nitrogen adsorption-desorption curve diagram of the supramolecular polymer porous material PTP3 of the present invention; Figure 5 A schematic diagram of the structure of the dye adsorbed by the supramolecular polymer porous material PTP3 of the present invention; Figure 6 This is a comparison chart of the adsorption rate of dyes by the supramolecular polymer porous material PTP3 of the present invention; Figure 7 This is a comparison chart of the amount of adsorbent used in the supramolecular polymer porous material PTP3 of the present invention; Figure 8 This is a diagram of the recycling use of the supramolecular polymer porous material PTP3 of the present invention. DETAILED DESCRIPTION

[0019] The synthesis of the supramolecular polymer porous material PTP3 of the present invention and its application in adsorbing dyes in water are further described below through specific examples.

[0020] Example 1. Synthesis of supramolecular polymer porous material PTP3 (1) Synthesis of compound TP: p-Dibromobenzene (2.36 g, 10 mmol) and 2,4-dimethoxyphenylboronic acid (3.64 g, 20 mmol) were dissolved in 25 mL of solvent (water:1,4-dioxane=1:4, V:V) and a catalyst [1,1'-bis(diphenylphosphino)ferrocene]palladium dichloride (0.366 g, 0.5 mmol) was added. Then sodium carbonate (2.12 g, 20 mmol) was added while stirring. The mixture was reacted at 101 °C for 12 h under anaerobic conditions. After the reaction, 1,4-dioxane was dried by spin drying at 65 °C, and then water was added to separate the mixture and extracted with dichloromethane until no product was found in the upper aqueous phase. Then, anhydrous sodium sulfate was added to the organic phase to dry it and then concentrated in vacuo. A white solid was obtained by column chromatography, which was compound TP (2.73 g). Yield: 78%; Melting point: 165~170 ℃.

[0021] (2) Synthesis of compound TP3: Compound TP (1 g, 2.85 mmol) and paraformaldehyde (107 mg, 3.567 mmol) were dissolved in 100 mL of 1,2-dichloroethane, stirred at room temperature and slowly added with boron trifluoride etherate (500 µL) for 2 h until the reactants were completely reacted. After the reaction was complete, the reaction solution was directly added to a saturated sodium bicarbonate solution to quench, then separated and dried over anhydrous sodium sulfate, and the resulting solution was concentrated in vacuo. A white solid was obtained by column chromatography, namely compound TP3 (0.72 g). Yield: 70%; Melting point: 254~260°C.

[0022] (3) Synthesis of compound OH-TP3: Compound TP3 (0.272 g, 0.25 mmol) was dissolved in 50 mL of dichloromethane, stirred at room temperature and 1.13 mL (12 mmol) of boron tribromide was slowly added. After the reaction was sealed for 48 h, the resulting reaction solution was pipetted into an appropriate amount of ice water bath to obtain a white solid, which was then filtered and rinsed with dichloromethane to obtain compound OH-TP3.

[0023] (4) Synthesis of compound PTP3: Compound OH-TP3 (0.36 g, 0.4 mmol), 1,2-dibromoethane (0.35 mL, 3.6 mmol), and triphenylphosphine (0.43 g, 1.6 mmol) were dissolved in a two-necked flask containing 60 mL of acetonitrile and heated to 75 °C under a N2 atmosphere for 48 h. After the reaction, the precipitate was collected by filtration, rinsed with water and methanol, and dried and weighed to obtain 60 mg of an orange-red solid, which was compound PTP3.

[0024] Example 2: Removal of dyes from water by adsorption using supramolecular polymer porous material PTP3 1 mg of supramolecular polymer porous material PTP3 was added to four centrifuge tubes, and 3 mL of aqueous solution of methyl green, rhodamine B, methyl orange, and acid chrome blue K were added respectively. The centrifuge tubes were fixed on a magnetic stirrer for stirring. Then, the absorbance of the dye was measured by UV spectrophotometry after a certain time interval. It can be seen with the naked eye that the color of the dye solution gradually fades with the passage of time; the trend of the absorbance of the dye molecule decreasing over time can also be seen in the UV spectrum. Next, we added 1.5 mL of aqueous solution of two dyes to the centrifuge tube added with 1 mg of supramolecular polymer porous material PTP3, and also measured the absorbance of the dye by UV spectrophotometry after a certain time interval. We obtained the same result as the adsorption and removal of single-component dyes, and the supramolecular polymer porous material PTP3 has a faster rate of adsorption and removal of multi-component dyes. In order to further explore the performance of supramolecular polymer porous material PTP3 in adsorbing and removing multi-component dyes, we selected methyl green and rhodamine B as pollution models. The adsorption comparison of methyl green, rhodamine B and mixed dyes of methyl green and rhodamine B by supramolecular polymer porous material PTP3 showed that 0.2 mg of PTP3 can remove the mixed dyes of methyl green and rhodamine B in aqueous solution, while 0.3 mg is required for either methyl green or rhodamine B alone. Combined with the above results, we believe that when supramolecular polymer porous material PTP3 adsorbs and removes mixed dye solutions, its cavity and its network structure achieve a synergistic effect, which promotes the adsorption and removal of dye molecules.

Claims

1. A supramolecular polymer porous material PTP3, whose structural formula is: 。 2. The method for preparing the supramolecular polymer porous material PTP3 according to claim 1, comprising the following steps: (1) Synthesis of compound TP: p-dibromobenzene and 2,4-dimethoxyphenylboronic acid are used as substrates, 1,4-dioxane / water mixture is used as solvent, sodium carbonate and [1,1'-bis(diphenylphosphino)ferrocene]palladium dichloride are added, and the mixture is reacted at 100-105°C for 10-15h under nitrogen protection; after the reaction, 1,4-dioxane is dried at 60-70°C and extracted with dichloroethane; the combined organic phase is concentrated, and the residue is separated by column chromatography to obtain a white solid, which is compound TP; (2) Synthesis of compound TP3: Compound TP and paraformaldehyde were used as substrates, 1,2-dichloroethane was used as solvent, and boron trifluoride ether was slowly added to react at room temperature for 1-3 hours; after the reaction was completed, the reaction solution was directly added to a saturated sodium bicarbonate solution to quench; the combined organic phase was concentrated after extraction and dried over anhydrous sodium sulfate; the residue was subjected to column chromatography to obtain a white solid, and the obtained product was compound TP3; (3) Synthesis of compound OH-TP3: Using compound TP3 as substrate and dichloromethane as solvent, slowly add boron tribromide and react at room temperature for 45-50 hours. After the reaction, add the reaction solution into ice water with a pipette to precipitate a white solid. Filter and rinse with dichloromethane to obtain compound OH-TP3. (4) Synthesis of compound PTP3: Using compound OH-TP3 as substrate, 1,2-dibromoethane as cross-linking agent, acetonitrile as solvent, and triphenylphosphine, the reaction was carried out at 70-80°C for 48 h under nitrogen protection. After the reaction, an orange-red solid was precipitated, which was filtered and washed with water and methanol. The resulting product was compound PTP3.

3. The method for preparing the supramolecular polymer porous material PTP3 according to claim 2, characterized in that: In step (1), the molar ratio of p-dibromobenzene to 2,4-dimethoxyphenylboric acid is 1:1 to 1:

3.

4. The method for preparing the supramolecular polymer porous material PTP3 according to claim 2, characterized in that: In step (1), in the 1,4-dioxane / water mixture, the volume ratio of 1,4-dioxane to water is 3:1 to 5:

1.

5. The method for preparing the supramolecular polymer porous material PTP3 according to claim 2, characterized in that: In step (1), the molar ratio of p-dibromobenzene to [1,1'-bis(diphenylphosphino)ferrocene]palladium dichloride is 18:1-22:1; and the molar ratio of p-dibromobenzene to sodium carbonate is 1:1-1:

3.

6. The method for preparing the supramolecular polymer porous material PTP3 according to claim 2, characterized in that: In step (2), the molar ratio of compound TP to paraformaldehyde is 1:1 to 1:

2.

7. The method for preparing the supramolecular polymer porous material PTP3 according to claim 2, characterized in that: In step (3), the molar ratio of compound TP3 to boron tribromide is 1:45 to 1:

50.

8. The method for preparing the supramolecular polymer porous material PTP3 according to claim 2, characterized in that: In step (4), the molar ratio of compound OH-TP3 to 1,2-dibromoethane is 1:8-1:10; the molar ratio of compound OH-TP3 to triphenylphosphine is 1:3-1:

5.

9. Use of the supramolecular polymer porous material PTP3 according to claim 1 in removing dyes from water.

10. The use of the supramolecular polymer porous material PTP3 according to claim 9 in removing dyes from water, characterized in that: The supramolecular polymer porous material PTP3 synergistically adsorbs at least two of methyl green, rhodamine B, methyl orange and acid chrome blue K.

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