Long alkyl chain strong anion exchange resin and preparation method thereof

Abstract

The invention discloses long alkyl chain strong anion exchange resin and a preparation method thereof, which are characterized in that a double bond-containing polymerizable monomer, a cross-linking agent and a halogen-containing polymerizable functional monomer are used for preparing a halogen functionalized microsphere matrix by using a suspension polymerization or seed swelling method, and then the halogen functionalized microsphere matrix reacts with a long alkyl chain amino functional monomer to obtain the long alkyl chain strong anion exchange resin. And finally, carrying out post-modification by using a halogen-containing long alkyl chain quaternary ammonium salt to obtain the novel long alkyl chain strong anion exchange resin. The long alkyl chain strong anion exchange resin synthesized by the method has the advantages of simple synthesis process, controllable number of quaternary ammonium groups, no use of toxic organic reagents, and large-scale preparation.

Description

Technical Field

[0001] This invention relates to a strong anion exchange resin and its preparation method, specifically to a long alkyl chain strong anion exchange resin microsphere, its preparation method, and its application, belonging to the technical field of adsorption and separation material preparation and application. Background Technology

[0002] Strong anion exchange resins are a class of resins containing strongly basic groups in their structure. Because their ion exchange groups can adsorb ions and compounds with opposite charges, they are widely used in ion chromatography packing materials, water treatment, separation of active ingredients from traditional Chinese medicine, and protein separation. Long-alkyl chain strong anion exchange resins can enhance the resin's hydrophobicity, making them more affinityous for organic anions and enabling efficient adsorption of hydrophobic anionic compounds. Simultaneously, they can reduce interference from other ions, improving the selectivity and separation efficiency for organic anions.

[0003] Currently, several synthetic methods for long-chain alkyl strong anion exchange resins have been reported. Patent CN117756991A discloses a method using cross-linked polystyrene white spheres as seed microspheres. Utilizing seed polymerization technology with glycidyl methacrylate as a monomer, the seed microspheres undergo swelling polymerization to obtain core-shell resin microspheres. These microspheres then form a backbone by ring-opening the epoxy groups into hydroxyl groups using sulfuric acid solution. This backbone is then reacted with synthesized 2,3-epoxypropyltrimethylammonium chloride (GTA) to obtain a strong basic anion exchange resin containing long-chain alkyl quaternary ammonium groups. This process requires sulfuric acid solution, demands sophisticated industrial equipment, is not environmentally friendly, and is unsuitable for industrial production. Patent CN103755846A discloses a process that uses cross-linked polystyrene white spheres as a backbone, uses chloromethyl ether as an alkylating agent to attach benzyl chloride to the white sphere backbone via a Friedel-Crafts reaction, and then performs an amination reaction with a long-chain alkylamine to obtain a strongly basic anion exchange resin. The chloromethyl ether used in this process is highly toxic and is on the list of Class 1 carcinogens, and is also environmentally unfriendly.

[0004] Current technologies for synthesizing long alkyl chain strong anion exchange resins generally suffer from drawbacks such as complex processes, the use of toxic or highly toxic reagents, and environmental unfriendliness. Therefore, this invention provides a simple method for preparing long alkyl chain strong anion exchange resins that does not use highly toxic reagents, is easy to synthesize industrially, and allows for controllable strong anion exchange capacity, thus overcoming the shortcomings of existing processes. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to address the shortcomings of the existing technology by providing a long alkyl chain strong anion exchange resin and its preparation method. The method of the present invention is simple, environmentally friendly, has controllable strong anion exchange capacity, and is easy to synthesize industrially.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: This invention first provides a method for preparing a long alkyl chain strong anion exchange resin, comprising the following steps: (1) Mix the polymerizable monomer, crosslinking agent and halogen-containing polymerizable functional monomer in a certain proportion, then add the initiator for ultrasonic dissolution, then add the stabilizer for polymerization, filter after polymerization, wash with water and ethanol several times, and dry to obtain a long alkyl chain strong anion exchange resin matrix. (2) Take a certain amount of long alkyl chain strong anion exchange resin matrix and disperse it in a dispersant. Add a certain amount of long alkyl chain amino functional monomer and react under certain conditions. After the reaction is completed, filter it, wash it several times with water and ethanol respectively, and dry it to obtain the long alkyl chain strong anion exchange resin intermediate. (3) Take a certain amount of long alkyl chain strong anion exchange resin intermediate and disperse it in a dispersant. Add a certain amount of halogen-containing long alkyl chain quaternary ammonium and react under certain conditions. After the reaction is completed, filter it, wash it several times with water and ethanol respectively, and dry it to obtain a new type of long alkyl chain strong anion exchange resin.

[0007] In the above technical solution, in step (1), the polymerizable monomers include, but are not limited to, styrene, ethylstyrene, methacrylates, acrylates, etc.; the crosslinking agents include, but are not limited to, divinylbenzene, ethylene glycol dimethacrylate, etc.; the halogen-containing polymerizable functional monomers include, but are not limited to, vinyl benzyl chloride, vinyl chloride, allyl chloride, etc.; the initiators include, but are not limited to, azobisisobutyronitrile, azobisisoheptanenitrile, benzoyl peroxide, dilauryl peroxide, etc.; the stabilizers include, but are not limited to, polyvinyl alcohol solution, polyvinylpyrrolidone solution, hydroxypropyl cellulose aqueous solution, hydroxypropyl methyl cellulose aqueous solution, dextran solution, agar solution, gelatin solution, etc.

[0008] In the above technical solution, in step (1), the mass ratio of the polymerizable monomer, crosslinking agent, and halogen-containing polymerizable functional monomer is 1:(0.01~10):(0.01~10); the mass of the initiator is 0.1%~10% of the mass of the polymerizable monomer, and the mass fraction of the polymerizable monomer, crosslinking agent, and halogen-containing polymerizable functional monomer in the reaction system is 1%~50%; the mass of the stabilizer is 0.01%~10% of the total mass of the polymerizable monomer, crosslinking agent, and halogen-containing polymerizable functional monomer.

[0009] In the above technical solution, in step (1), the polymerization method includes, but is not limited to, seed swelling polymerization and suspension polymerization, wherein seed swelling polymerization yields a monodisperse long alkyl chain strong anion exchange resin matrix, and suspension polymerization yields a polydisperse long alkyl chain strong anion exchange resin matrix.

[0010] In the above technical solution, step (1), the seed swelling polymerization specifically includes the following steps: first, the PS microspheres are swollen; then, the polymerizable monomer, crosslinking agent and halogen-containing polymerizable functional monomer are mixed in a certain proportion and an initiator is added and ultrasonically dissolved, then sodium dodecyl sulfonate aqueous solution is added for ultrasonic emulsification, and then the emulsion solution is added to the PS microspheres to continue swelling; finally, a stabilizer is added to the system, the temperature is raised to 50~90℃, and the reaction is carried out at 100~500 r / min for 4~48h; after the reaction is completed, the mixture is filtered, washed several times with water and ethanol respectively, and dried at 30~90℃ to obtain a long alkyl chain strong anion exchange resin matrix.

[0011] In the above technical solution, the suspension polymerization in step (2) specifically includes the following steps: mixing the polymerizable monomer, crosslinking agent and halogen-containing polymerizable functional monomer in a certain proportion, then adding an initiator for ultrasonic dissolution, finally adding a stabilizer, stirring at 30~50 ℃ and 100~500 r / min for 1~5 h, heating to 40~90 ℃ and reacting for 4~48 h for polymerization, filtering after polymerization, washing several times with water and ethanol respectively, and drying at 30~90 ℃ to obtain a long alkyl chain strong anion exchange resin matrix.

[0012] In the above technical solution, in step (2), the dispersant can be an organic solvent such as ethanol, methanol, acetonitrile, tetrahydrofuran, or an aqueous solution of different proportions thereof; the long alkyl chain amine functional monomer is a functional group containing two or more nitrogen atoms, including but not limited to compounds with the following structural formula: , where n>3.

[0013] In the above technical solution, in step (2), the mass of the long alkyl chain amine functional monomer is 0.1% to 100% of the mass of the long alkyl chain strong anion exchange resin matrix; the reaction conditions are 50 to 500 r / min, 50 to 100 ℃, and 2 to 48 h; the number of times of washing with water and ethanol is 2 to 5, and the drying temperature is 30 to 90 ℃.

[0014] In the above technical solution, in step (3), the dispersant can be an organic solvent such as ethanol, methanol, acetonitrile, tetrahydrofuran, or an aqueous solution of the same solvent in different proportions; the halogen-containing long alkyl chain quaternary ammonium includes, but is not limited to, compounds with the following structural formula: , where n>3.

[0015] In the above technical solution, in step (3), the mass of the halogen-containing long alkyl chain quaternary ammonium is 0.1% to 100% of the mass of the long alkyl chain strong anion exchange resin intermediate; the reaction conditions are: stirring speed of 50 to 500 r / min, reaction temperature of 50 to 100 ℃, reaction time of 2 to 48 h; washing with water and ethanol 2 to 5 times respectively, and drying temperature of 20 to 70 ℃.

[0016] The second objective of this invention is to provide a long alkyl chain strong anion exchange resin obtained by the above preparation method.

[0017] A third objective of this invention is to provide a long alkyl chain strong anion exchange resin for the separation of flavonoids and acid compounds in traditional Chinese medicine.

[0018] The present invention has the following advantages over the prior art: 1. The synthesis process of long alkyl chain strong anion exchange resin is simple, environmentally friendly, and easy to industrialize; 2. The ion exchange capacity of long alkyl chain strong anion exchange resins is controllable. Attached Figure Description

[0019] Figure 1 SEM image of the monodisperse long alkyl chain strong anion exchange resin obtained in Example 1; Figure 2 SEM image of the polydisperse long alkyl chain strong anion exchange resin obtained in Example 2. Detailed Implementation

[0020] The present invention will now be described in detail with reference to specific examples and accompanying drawings, but the present invention is not limited to the following description: Example 1: A long alkyl chain strong anion exchange resin is prepared by the following method, including the following steps: (1) Preparation of long alkyl chain strong anion exchange resin matrix by seed swelling polymerization: A. Weigh 20 g of swellable, monodisperse 2.5 μm PS microspheres and add them to 1000 mL of 0.15% sodium dodecyl sulfonate aqueous solution. Disperse by sonication for 30 min. Take 200 g of dimethyl phthalate and add it to 1000 mL of 0.15% sodium dodecyl sulfonate aqueous solution. Disperse by sonication for 30 min. Then mix the two solutions in a 5000 mL three-necked round-bottom flask and allow them to swell for 24 h at 35 ℃ and 180 r / min. B. Weigh 100 g styrene, 100 g ethylene glycol dimethacrylate, 20 g vinyl benzyl chloride and 5 g benzoyl peroxide and dissolve them by sonication. Then add them to 1500 mL of 0.15% sodium dodecyl sulfonate water and sonicate for 30 min. Add this solution to the reactor and continue to swell for 20 h at 35 ℃ and 180 r / min. C. Add 500 mL of 10% hydroxypropyl methylcellulose aqueous solution, heat to 70℃, and react at 350 r / min for 24 h. After the reaction is complete, filter, wash three times with water and ethanol respectively, and dry at 70℃ to obtain a monodisperse long alkyl chain strong anion exchange resin matrix. (2) Accurately weigh 200 g of monodisperse long alkyl chain strong anion exchange resin and add it to 4000 mL of 60% ethanol. Disperse it by ultrasonication for 20 min, add 50 g of hexamethylenediamine, and after 12 h at 300 r / min and 50℃, filter it, wash it 4 times with water and ethanol respectively, and dry it at 60℃ to obtain the monodisperse long alkyl chain strong anion exchange resin intermediate. (3) Take 100 g of monodisperse long alkyl chain strong anion exchange resin intermediate and add it to 3000 mL of 60% acetonitrile. Disperse it ultrasonically for 20 min. Add 10 g of 6-bromohexyltrimethylammonium bromide and disperse it at 200 r / min and 70℃ for 10 h. Filter the mixture and wash it four times with water and ethanol respectively. Dry it at 60℃ to obtain monodisperse long alkyl chain strong anion exchange resin. The SEM image of the monodisperse long alkyl chain strong anion exchange resin is shown below. Figure 1 As shown, by Figure 1 It can be seen that the synthesized monodisperse long alkyl chain strong anion exchange resin has a uniform spherical morphology with a particle size of about 10 μm.

[0021] Example 2: A long alkyl chain strong anion exchange resin is prepared by the following method, including the following steps: (1) Preparation of long alkyl chain strong anion exchange resin matrix by suspension polymerization: Weigh 200 g styrene, 200 g divinylbenzene, 50 g vinylbenzyl chloride and 10 g azobisisobutyronitrile and dissolve them by sonication. Add them to 4000 mL of 1% gelatin solution. Stir at 50 °C and 300 r / min for 1 h. Then heat to 70 °C and react for 24 h. After the reaction is complete, filter, wash three times with water and ethanol respectively, and dry at 60 °C to obtain a polydisperse long alkyl chain strong anion exchange resin matrix. (2) Accurately weigh 200 g of polydisperse long alkyl chain strong anion exchange resin and add it to 4000 mL of 80% ethanol. Disperse it by ultrasonication for 20 min. Add 50 g of 2,6,10-trimethyl-2,6,10-triazaundecane. After 16 h at 200 r / min and 60℃, filter it and wash it three times with water and ethanol respectively. Dry it at 50℃ to produce polydisperse long alkyl chain strong anion exchange resin intermediate. (3) Take 100 g of the polydisperse long alkyl chain strong anion exchange resin intermediate and add it to 3000 mL of 80% acetonitrile. Disperse it ultrasonically for 20 min. Add 10 g of 3-bromopropyltrimethylammonium bromide and disperse it at 200 r / min and 70℃ for 10 h. Filter the mixture and wash it three times with water and ethanol respectively. Dry it at 50℃ to obtain the polydisperse long alkyl chain strong anion exchange resin. The SEM image of the polydisperse long alkyl chain strong anion exchange resin is shown below. Figure 2 As shown, by Figure 2 It can be seen that the synthesized polydisperse long alkyl chain strong anion exchange resin has a regular spherical morphology with a particle size between 400 and 800 μm.

[0022] Application Examples: The wolfberry leaves were extracted twice by reflux with 60% ethanol at a material-to-liquid ratio of 1:10. After extraction, the concentration was concentrated to a concentration equivalent to 100g of leaves per liter. The extract was then adsorbed for 2 hours using a long alkyl chain strong anion exchange resin at a material-to-liquid ratio of 1:10. After adsorption, 60% ethanol was used as the desorbent and desorbed for 2 hours at a material-to-liquid ratio of 1:15. After adsorption, the total flavonoid content, yield, and extract yield were measured. The results are shown in Table 1.

[0023] Salvia miltiorrhiza was extracted twice by reflux with 70% ethanol at a material-to-liquid ratio of 1:10. After extraction, the extract was concentrated to a concentration equivalent to 50g of Salvia miltiorrhiza per liter. Long alkyl chain strong anion exchange resin was used for adsorption at a material-to-liquid ratio of 1:10 for 2 hours. Then, 60% ethanol was used as the desorbent and desorbed at a material-to-liquid ratio of 1:15 for 2 hours. After adsorption, the content, yield and extract yield of tanshinone A and tanshinone B were measured. The results are shown in Table 1.

[0024] As shown in Table 1, the long alkyl chain strong anion exchange resin obtained by the present invention has the advantages of high adsorption efficiency for anionic organic compounds, high product content, and simple operation without the need for column packing.

[0025] The present invention illustrates the main preparation process and simple application of the long alkyl chain strong anion exchange resin of the present invention through the above embodiments. However, the present invention is not limited to the above embodiments. All equivalent transformations or modifications made in accordance with the essence of the present invention, as well as the application of the long alkyl chain strong anion exchange resin, should be covered within the protection scope of the present invention.

Claims

1. A method for preparing a long alkyl chain strong anion exchange resin, characterized in that, Includes the following steps: (1) Mix the polymerizable monomer, crosslinking agent and halogen-containing polymerizable functional monomer in a certain proportion, then add the initiator for ultrasonic dissolution, then add the stabilizer for polymerization, filter after polymerization, wash with water and ethanol several times, and dry to obtain a long alkyl chain strong anion exchange resin matrix. (2) Take a certain amount of long alkyl chain strong anion exchange resin matrix and disperse it in a dispersant. Add a certain amount of long alkyl chain amino functional monomer and react under certain conditions. After the reaction is completed, filter it, wash it several times with water and ethanol respectively, and dry it to obtain the long alkyl chain strong anion exchange resin intermediate. (3) Take a certain amount of long alkyl chain strong anion exchange resin intermediate and disperse it in a dispersant. Add a certain amount of halogen-containing long alkyl chain quaternary ammonium and react under certain conditions. After the reaction is completed, filter it, wash it several times with water and ethanol respectively, and dry it to obtain a new type of long alkyl chain strong anion exchange resin.

2. The preparation method according to claim 1, characterized in that, In step (1), the polymerizable monomers include, but are not limited to, styrene, ethylstyrene, methacrylates, and acrylates; the crosslinking agents include, but are not limited to, divinylbenzene and ethylene glycol dimethacrylate; the halogen-containing polymerizable functional monomers include, but are not limited to, vinyl benzyl chloride, vinyl chloride, and allyl chloride; the initiators include, but are not limited to, azobisisobutyronitrile, azobisisoheptanenitrile, benzoyl peroxide, and dilauryl peroxide; and the stabilizers include, but are not limited to, polyvinyl alcohol solution, polyvinylpyrrolidone solution, hydroxypropyl cellulose aqueous solution, hydroxypropyl methylcellulose aqueous solution, dextran solution, agar solution, and gelatin solution.

3. The preparation method according to claim 1, characterized in that, In step (1), the mass ratio of the polymerizable monomer, crosslinking agent, and halogen-containing polymerizable functional monomer is 1:(0.01~10):(0.01~10); the mass of the initiator is 0.1%~10% of the mass of the polymerizable monomer, and the mass fraction of the polymerizable monomer, crosslinking agent, and halogen-containing polymerizable functional monomer in the reaction system is 1%~50%; the mass of the stabilizer is 0.01%~10% of the total mass of the polymerizable monomer, crosslinking agent, and halogen-containing polymerizable functional monomer.

4. The preparation method according to claim 1, characterized in that, In step (1), the polymerization method includes, but is not limited to, seed swelling polymerization and suspension polymerization, wherein seed swelling polymerization yields a monodisperse long alkyl chain strong anion exchange resin matrix, and suspension polymerization yields a polydisperse long alkyl chain strong anion exchange resin matrix.

5. The preparation method according to claim 4, characterized in that, In step (1), the seed swelling polymerization specifically includes the following steps: first, the PS microspheres are swollen; then, the polymerizable monomer, crosslinking agent and halogen-containing polymerizable functional monomer are mixed in a certain proportion and an initiator is added and ultrasonically dissolved; then, sodium dodecyl sulfonate aqueous solution is added and ultrasonically emulsified; then, the emulsion solution is added to the PS microspheres to continue swelling; finally, a stabilizer is added to the system, the temperature is raised to 50~90℃, and the reaction is carried out at 100~500 r / min for 4~48 h; after the reaction is completed, the mixture is filtered, washed several times with water and ethanol respectively, and dried at 30~90℃ to obtain a long alkyl chain strong anion exchange resin matrix.

6. The preparation method according to claim 4, characterized in that, In step (2), the suspension polymerization specifically includes the following steps: mixing the polymerizable monomer, crosslinking agent and halogen-containing polymerizable functional monomer in a certain proportion, then adding an initiator for ultrasonic dissolution, finally adding a stabilizer, stirring at 30~50 ℃ and 100~500 r / min for 1~5 h, heating to 40~90 ℃ and reacting for 4~48 h for polymerization, filtering after polymerization, washing several times with water and ethanol respectively, and drying at 30~90 ℃ to obtain a long alkyl chain strong anion exchange resin matrix.

7. The preparation method according to claim 1, characterized in that, In step (2), the dispersant can be an organic solvent such as ethanol, methanol, acetonitrile, tetrahydrofuran, or an aqueous solution of the same solvent in different proportions; the long alkyl chain amine functional monomer is a functional group containing two or more nitrogen atoms, including but not limited to compounds with the following structural formula: , where n>

3.

8. The preparation method according to claim 1, characterized in that, In step (2), the mass of the long alkyl chain amine functional monomer is 0.1% to 100% of the mass of the long alkyl chain strong anion exchange resin matrix; the reaction conditions are 50 to 500 r / min, 50 to 100 ℃, and 2 to 48 h; the number of times of washing with water and ethanol is 2 to 5, and the drying temperature is 30 to 90 ℃.

9. The preparation method according to claim 1, characterized in that, In step (3), the dispersant can be an organic solvent such as ethanol, methanol, acetonitrile, tetrahydrofuran, or an aqueous solution of the same solvent in different proportions; the halogen-containing long alkyl chain quaternary ammonium includes, but is not limited to, compounds with the following structural formula: , where n>

3.

10. The preparation method according to claim 1, characterized in that, In step (3), the mass of the halogen-containing long alkyl chain quaternary ammonium is 0.1% to 100% of the mass of the long alkyl chain strong anion exchange resin intermediate; the reaction conditions are as follows: stirring speed is 50 to 500 r / min, reaction temperature is 50 to 100 ℃, reaction time is 2 to 48 h; the number of times of washing with water and ethanol is 2 to 5, and the drying temperature is 20 to 70 ℃.

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