Method for manufacturing fouling-resistant films based on amphoteric dynamic supramolecules

Abstract

Conventional water treatment membranes are prone to fouling due to the adhesion of contaminants, making it difficult to achieve both high flux and high fouling resistance. Furthermore, manufacturing costs are high, and regenerating membrane performance is complicated. [Solution] This invention relates to a method for producing a fouling-resistant film based on an amphoteric dynamic supramolecular. A high-flux base film is formed by a non-solvent-induced phase separation method, and an amphoteric supramolecular with a pseudo-polyrotaxane structure is synthesized by a solvent-induced self-assembly method. This supramolecular structure, composed of cyclodextrin and polydimethylsiloxane, allows hydrophilic and low-surface-energy microdomains to work together to prevent contamination, achieving high flux and low decay rate of the film. The manufacturing process is simple, the raw materials are inexpensive, the film can be easily regenerated by washing, and it exhibits excellent adaptability over a wide temperature and pH range.

Description

[Technical Field]

[0001] This invention belongs to the field of water treatment membrane manufacturing technology, and more specifically relates to a method for manufacturing fouling-resistant membranes based on amphoteric dynamic supramolecular technology. [Background technology]

[0002] In the development of water treatment technology, membrane fouling has always been one of the main problems limiting membrane performance and service life. To improve the fouling resistance of water treatment membranes, hydrophilic modification has become a widely used strategy. The surface of a hydrophilic membrane preferentially adsorbs water molecules and forms a protective layer of hydration, effectively preventing the direct adhesion of foulants. This fouling resistance mechanism is called the "fouling resistance mechanism" and has a certain effect in many water treatment applications. However, while hydrophilic membranes can prevent foulant adhesion in the initial stages, hydrophilic modification cannot completely prevent foulant accumulation once the membrane has deformed and adhered to the membrane surface, still leading to a decrease in membrane performance after long-term use.

[0003] To further improve the fouling resistance of membranes, heterogeneous membranes have attracted attention. Such membranes combine two mechanisms—fouling resistance and fouling release—by constructing heterogeneous microdomains with hydrophilicity and low surface energy on the membrane surface. Hydrophilic microdomains can prevent initial adhesion of foulants, while low surface energy microdomains promote foulant release under external perturbation conditions by reducing the adhesion between the foulants and the membrane surface. Such a cooperative fouling resistance mechanism can significantly improve the fouling resistance of membranes in practical operation, and low surface energy microdomains can effectively reduce foulant residue, especially when some foulants have already adhered. However, the application of heterogeneous membranes in water treatment also faces several challenges. While this mechanism generally relies on relatively strong tangential flow, hydrophobic microdomains with low surface energy can increase the membrane's water flow resistance and affect the membrane's water flux. Therefore, improving the underlying flux of heterogeneous fouling-resistant membranes and eliminating their dependence on tangential flow velocity is a focus of research and development in this field. This is expected to enable the production of high-quality water treatment membranes that combine low cost, high flux, and fouling resistance, thereby solving the problem of conventional membranes being prone to contamination and performance degradation during water treatment. [Overview of the Initiative] [Problems that the invention aims to solve]

[0004] The direct object of the present invention is to improve the base flux of heterogeneous fouling-resistant membranes and solve the problem of the heterogeneous membrane's dependence on tangential flow velocity. The ultimate objective is to produce a high-quality water treatment membrane that combines low cost, high flux, and fouling resistance. Therefore, the present invention provides a method for producing a fouling-resistant membrane based on an amphoteric dynamic supramolecular system. [Means for solving the problem]

[0005] A method for producing a fouling-resistant film based on an amphoteric dynamic supramolecular, which is carried out according to the following steps: 1. Production of high-flux polyethersulfone film: A casting solution is formed by mixing polyethersulfone, polyvinylpyrrolidone, Pluronic F127, and dimethylformamide in a mass ratio of 14:7:7:72. The mixture is then stirred at 70°C for 4 hours, allowed to stand at 70°C for 4 hours to remove air bubbles, and after the casting solution has cooled naturally to 25°C, it is applied to a glass plate to form a 250 μm thick liquid film. The film is then immersed in a special coagulation bath for 5 minutes to obtain a base film, and immersed in deionized water for ≥12 hours to prepare for use. 2. Production of hydrophilic, low-surface-energy amphoteric supramolecules: Polydimethylsiloxane is added to a saturated cyclodextrin solution, followed by sonication, shaking, and standing in sequence, and the product is precipitated. Further extraction and washing with cyclohexane, washing with distilled water, and vacuum drying are performed to obtain a hydrophilic, low-surface-energy amphoteric dynamic supramolecular, i.e., cyclodextrin / polydimethylsiloxane pseudopolyrotaxane. A cyclodextrin / polydimethylsiloxane pseudopolyrotaxane dispersion is then prepared. III. Manufacturing of a hydrophilic, low-surface-energy dynamic fouling-resistant layer: The substrate film produced in Step 1 is coated with a desalted glycidyl methacrylate aqueous solution, then irradiated with ultraviolet light under nitrogen gas protection, and further washed with deionized water to obtain film A. At room temperature, film A is immersed for 12 hours in the cyclodextrin / polydimethylsiloxane pseudopolyrotaxane dispersion prepared in step 2, and after removal, is further immersed for 3 hours in a fluorescein-4-isothiocyanate solution to obtain a hydrophilic, low-surface-energy dynamic fouling-resistant layer, i.e., a fouling-resistant film based on an amphoteric dynamic supramolecular, thus completing the manufacturing method. Here, regarding the precipitation of the product described in Step 2, the precipitation method is adapted to the type of cyclodextrin. If the cyclodextrin is β-cyclodextrin, 60% to 90% by weight of dimethylformamide is removed by rotary evaporation, and an equal mass of distilled water is added to induce precipitation of β-cyclodextrin / polydimethylsiloxane pseudopolyrotaxane. If the cyclodextrin is γ-cyclodextrin, the γ-cyclodextrin / polydimethylsiloxane pseudopolyrotaxane spontaneously forms a gel-like precipitate. Regarding the cyclodextrin / polydimethylsiloxane pseudopolyrotaxane obtained in Step 2, the molar ratio of cyclodextrin to polydimethylsiloxane is determined by the type of cyclodextrin and the mass input ratio of cyclodextrin to polydimethylsiloxane. When cyclodextrin is β-cyclodextrin, the mass input ratio of β-cyclodextrin to polydimethylsiloxane is (2.24~10.10):1, and the molar ratio of β-cyclodextrin to polydimethylsiloxane in the resulting cyclodextrin / polydimethylsiloxane pseudopolyrotaxane is (0.13~0.53):1. When the cyclodextrin is γ-cyclodextrin, the mass input ratio of γ-cyclodextrin to polydimethylsiloxane is (2.45~13.78):1, and the molar ratio of γ-cyclodextrin to polydimethylsiloxane in the resulting cyclodextrin / polydimethylsiloxane pseudopolyrotaxane is (0.13~0.67):1.

[0006] Furthermore, the special coagulation bath described in Step 1 consists of water and dimethylformamide, with a mass ratio of (1:8) to (8:1).

[0007] Furthermore, the cyclodextrin described in step 2 is β-cyclodextrin or γ-cyclodextrin, the polydimethylsiloxane terminal group is an aminopropyl group, and its molecular weight is 1000 to 5000 Da.

[0008] Furthermore, for the saturated cyclodextrin solution described in Step 2, here, the solvent used is compatible with the type of cyclodextrin. When the cyclodextrin is β-cyclodextrin, the solvent is dimethylformamide. When the cyclodextrin is γ-cyclodextrin, the solvent is water.

[0009] Furthermore, for the ultrasonic treatment, shaking, and standing still described in Step 2, the parameters are all compatible with the type of cyclodextrin. When the cyclodextrin is β-cyclodextrin, the ultrasonic treatment power is 500 - 1500 W, the time is 5 - 15 min, the shaking speed is 50 - 100 r / min, the time is 5 - 10 d, and the standing still time is 2 d. When the cyclodextrin is γ-cyclodextrin, the ultrasonic treatment power is 200 - 600 W, the time is 3 - 9 min, the shaking speed is 50 - 100 r / min, the time is 10 - 30 h, and the standing still time is 5 - 8 h.

[0010] Furthermore, for the cyclodextrin / polydimethylsiloxane pseudo-polyrotaxane dispersion prepared in Step 2, the solute concentration in the dispersion is 1 - 3 g / L, the solvents are dimethylformamide and distilled water. Here, the volume ratio of dimethylformamide to distilled water is (2:1) - (1:2). For the preparation of the dispersion, the cyclodextrin / polydimethylsiloxane pseudo-polyrotaxane is dissolved in dimethylformamide, and distilled water is added to ensure effective dispersion.

[0011] Furthermore, the mass concentration of the glycidyl methacrylate aqueous solution described in Step 3 is 1% - 3%, and the coating amount is 100 μl / cm 2 is.

[0012] Furthermore, the usage amount of the cyclodextrin / polydimethylsiloxane pseudo-polyrotaxane dispersion described in Step 3 is 25 ml / cm 2 is.

[0013] Furthermore, regarding the ultraviolet irradiation described in Step 3, the ultraviolet intensity is 3 - 8 mW / cm 2 and the irradiation time length is 5 - 15 min.

[0014] Furthermore, regarding the fluorescein - 4 - isothiocyanate solution described in Step 3, the concentration is 2.5 - 7.5 mg / mL and the usage amount is 1.5 - 3.5 mL / cm 2 is.

[0015] Furthermore, the fouling - resistant membrane based on amphiphilic dynamic supramolecules obtained in Step 3 is immersed in deionized water for 24 h, and the water is exchanged every 8 h for preparation for use.

[0016] In the present invention, in the production of the fouling - resistant membrane based on amphiphilic dynamic supramolecules, that is, the fouling - resistant membrane based on heterogeneous supramolecular dynamics, for the first time, the cooperative fouling - resistant mechanism due to the hydrophilicity - low surface energy of the heterogeneous membrane and the supramolecular dynamic characteristics are combined. Compared with general heterogeneous membranes, the basic flux is higher, and the dependence on the tangential water flow velocity is smaller. In a weak perturbation environment, excellent fouling - resistant ability can be maintained. Compared with conventional supramolecular membranes, the interaction force between the host - guest of amphiphilic molecules is lower, the motility is stronger, and with the combined cooperative fouling - resistant mechanism, the fouling - resistant ability is increased by leaps and bounds.

Advantages of the Invention

[0017] Compared with the prior art, the present invention has the following advantages and beneficial effects.

[0018] (1) The raw materials used in the present invention are easily available, inexpensive, manufactured at room temperature, do not require protection by atmosphere, and can produce a fouling - resistant membrane based on amphiphilic dynamic supramolecules on a general membrane production line of production - surface coating modification by phase conversion.

[0019] (2) Compared to general heterogeneous films, the film flux is improved by 2 to 4 times, the flux decay rate of the fouling-resistant film based on amphoteric dynamic supramolecular technology is reduced by 40 to 65% under weak tangential flow conditions, and the flux decay rate of the film is reduced by 25 to 35% under strong tangential flow conditions, and almost 100% of the flux can be recovered by simple hydraulic washing.

[0020] (3) The fouling resistance of the fouling-resistant film itself, based on the amphoteric dynamic supramolecular, increases with increasing temperature, and can offset to a certain extent the increased tendency of the film to foul due to the increase in temperature, thus having a good applicable temperature range (5~50°C).

[0021] (4) Fouling-resistant membranes based on amphoteric dynamic supramolecules exhibit good properties in the pH range of 3 to 11, and can enhance the interaction between cyclodextrin and water molecules under alkaline conditions, which is advantageous for further increasing fouling resistance.

[0022] (5) The high flux, high adaptability, and low maintenance of the amphoteric dynamic supramolecular-based fouling-resistant membranes make them applicable to a variety of water treatment processes, including advanced treatment of drinking water, multi-stage treatment and reuse of wastewater.

[0023] This invention is applied to the production of fouling-resistant films based on amphoteric dynamic supramolecules. [Brief explanation of the drawing]

[0024] [Figure 1] These are flux data diagrams for Examples 1-9 and Comparative Examples at temperatures of 5°C, 20°C, 35°C, and 50°C, and a pressure of 1.0 bar, respectively. [Figure 2] These are flux data diagrams for Examples 1-9 and Comparative Examples at temperatures of 5°C, 20°C, 35°C, and 50°C, and a pressure of 1.0 bar, respectively. [Figure 3] These are flux data diagrams for Examples 1-9 and Comparative Examples at temperatures of 5°C, 20°C, 35°C, and 50°C, and a pressure of 1.0 bar, respectively. [Figure 4]These are flux data diagrams for Examples 1-9 and Comparative Examples at temperatures of 5°C, 20°C, 35°C, and 50°C, and a pressure of 1.0 bar, respectively. [Figure 5] This graph shows the bovine serum albumin (BSA) rejection rate data for Examples 1-9 and the Comparative Example. Here, the BSA concentration in the input material was 1 g / L, the environment was neutral, the temperature was 20°C, and the stirring speed was 60 rpm. [Figure 6] This diagram shows the fouling resistance data for BSA in Examples 1-9 and Comparative Examples, where BSA is used as a simulated foulant. Here, the test time for the base water flux is 15 min, the test time for the wastewater treatment flux is 30 min, the washing time is 15 min, and the test time for the water flux after washing is 15 min. The conditions are neutral, the temperature is 20°C, the operating agitation speed is 60 rpm, the washing agitation speed is 480 rpm, the flux decay rate (FDR) is (base water flux - wastewater treatment flux) / base water flux, and the flux recovery rate (FRR) is water flux after washing / base water flux. [Figure 7] These are data diagrams showing the fouling resistance of BSA as a simulated foulant under different pH environments, different stirring speed environments, and different temperature environments for Examples 3 and 6, respectively. [Figure 8] These are data diagrams showing the fouling resistance of BSA as a simulated foulant under different pH environments, different stirring speed environments, and different temperature environments for Examples 3 and 6, respectively. [Figure 9] These are data diagrams showing the fouling resistance of BSA as a simulated foulant under different pH environments, different stirring speed environments, and different temperature environments for Examples 3 and 6, respectively. [Figure 10]These are fouling resistance data diagrams for different simulated foulants from Examples 3 and 6, respectively. Here, the simulated foulants contained BSA, emulsified hexadecane, sodium alginate (SA), yeast, and humic acid (HA), all at a concentration of 1 g / L. The hexadecane emulsion also contained an additional 0.1 g / L of sodium dodecyl sulfate. The test time for the base water flux was 15 min, the wastewater treatment time was 30 min, the washing time was 15 min, and the test time for the water flux after washing was 15 min. This was repeated 5 times. The base water flux in the second cycle was the water flux after washing in the first cycle. The environment was neutral, the temperature was 20°C, the operating agitation speed was 60 rpm, and the washing agitation speed was 480 rpm. [Figure 11] These are fouling resistance data diagrams for different simulated foulants from Examples 3 and 6, respectively. Here, the simulated foulants contained BSA, emulsified hexadecane, sodium alginate (SA), yeast, and humic acid (HA), all at a concentration of 1 g / L. The hexadecane emulsion also contained an additional 0.1 g / L of sodium dodecyl sulfate. The test time for the base water flux was 15 min, the wastewater treatment time was 30 min, the washing time was 15 min, and the test time for the water flux after washing was 15 min. This was repeated 5 times. The base water flux in the second cycle was the water flux after washing in the first cycle. The environment was neutral, the temperature was 20°C, the operating agitation speed was 60 rpm, and the washing agitation speed was 480 rpm. [Modes for carrying out the invention]

[0025] The technical proposal of the present invention is not limited to the specific embodiments listed below, but further includes any combination of each specific embodiment.

[0026] Specific Embodiment 1: A method for manufacturing a fouling-resistant film based on the amphoteric dynamic supramolecular of this embodiment, which is carried out according to the following steps: 1. Production of high-flux polyethersulfone film: A casting solution is formed by mixing polyethersulfone, polyvinylpyrrolidone, Pluronic F127, and dimethylformamide in a mass ratio of 14:7:7:72. The mixture is then stirred at 70°C for 4 hours, allowed to stand at 70°C for 4 hours to remove air bubbles, and after the casting solution has cooled naturally to 25°C, it is applied to a glass plate to form a 250 μm thick liquid film. The film is then immersed in a special coagulation bath for 5 minutes to obtain a base film, and immersed in deionized water for ≥12 hours to prepare for use. 2. Production of hydrophilic, low-surface-energy amphoteric supramolecules: Polydimethylsiloxane is added to a saturated cyclodextrin solution, followed by sonication, shaking, and standing in sequence, and the product is precipitated. Further extraction and washing with cyclohexane, washing with distilled water, and vacuum drying are performed to obtain a hydrophilic, low-surface-energy amphoteric dynamic supramolecular, i.e., cyclodextrin / polydimethylsiloxane pseudopolyrotaxane. A cyclodextrin / polydimethylsiloxane pseudopolyrotaxane dispersion is then prepared. III. Manufacturing of a hydrophilic, low-surface-energy dynamic fouling-resistant layer: The substrate film produced in Step 1 is coated with a desalted glycidyl methacrylate aqueous solution, then irradiated with ultraviolet light under nitrogen gas protection, and further washed with deionized water to obtain film A. At room temperature, film A is immersed for 12 hours in the cyclodextrin / polydimethylsiloxane pseudopolyrotaxane dispersion prepared in step 2, and after removal, is further immersed for 3 hours in a fluorescein-4-isothiocyanate solution to obtain a hydrophilic, low-surface-energy dynamic fouling-resistant layer, i.e., a fouling-resistant film based on an amphoteric dynamic supramolecular, thus completing the manufacturing method. Here, regarding the precipitation of the product described in Step 2, the precipitation method is adapted to the type of cyclodextrin. If the cyclodextrin is β-cyclodextrin, 60% to 90% by weight of dimethylformamide is removed by rotary evaporation, and an equal mass of distilled water is added to induce precipitation of β-cyclodextrin / polydimethylsiloxane pseudopolyrotaxane. If the cyclodextrin is γ-cyclodextrin, the γ-cyclodextrin / polydimethylsiloxane pseudopolyrotaxane spontaneously forms a gel-like precipitate. Regarding the cyclodextrin / polydimethylsiloxane pseudopolyrotaxane obtained in Step 2, the molar ratio of cyclodextrin to polydimethylsiloxane is determined by the type of cyclodextrin and the mass input ratio of cyclodextrin to polydimethylsiloxane. When cyclodextrin is β-cyclodextrin, the mass input ratio of β-cyclodextrin to polydimethylsiloxane is (2.24~10.10):1, and the molar ratio of β-cyclodextrin to polydimethylsiloxane in the resulting cyclodextrin / polydimethylsiloxane pseudopolyrotaxane is (0.13~0.53):1. When the cyclodextrin is γ-cyclodextrin, the mass input ratio of γ-cyclodextrin to polydimethylsiloxane is (2.45~13.78):1, and the molar ratio of γ-cyclodextrin to polydimethylsiloxane in the resulting cyclodextrin / polydimethylsiloxane pseudopolyrotaxane is (0.13~0.67):1.

[0027] In step 1 of this embodiment, the production of a high-flux polyethersulfone film is carried out by combining non-solvent-induced phase separation and surface segregation.

[0028] The substrate membrane obtained in step 1 of this embodiment has a pore size at the ultrafiltration level, and its porosity is 10% to 50% higher than that of a typical ultrafiltration membrane.

[0029] The hydrophilic, low-surface-energy amphoteric supramolecular obtained in step 1 of this embodiment is a pseudopolyrotaxane structure in which "thread-like molecules penetrate cyclic molecules," where cyclodextrin is a hydrophilic cyclic host and polydimethylsiloxane is a low-surface-energy thread-like host.

[0030] The hydrophilic, low-surface-energy amphoteric supramolecule in step 2 of this embodiment is produced by a solvent-induced self-assembly method.

[0031] The purpose of UV irradiation in step 3 of this embodiment is to initiate radical polymerization and graft glycidyl methacrylate onto the substrate.

[0032] The purpose of washing with deionized water in step 3 of this embodiment is to remove unreacted glycidyl methacrylate from the base film.

[0033] In the immersion process described in step 3 of this embodiment, during the immersion in a cyclodextrin / polydimethylsiloxane pseudopolyrotaxane dispersion, an addition reaction occurs between the terminal amino groups of polydimethylsiloxane and the epoxy groups of glycidyl methacrylate, grafting both ends of most of the pseudopolyrotaxane to polyglycidyl methacrylate to form a "clothesline-shaped" structure, which is then converted to polyrotaxane by end capping. During the immersion in a fluorescein-4-isothiocyanate solution, the remaining amino groups are end capped, converting almost all of the pseudopolyrotaxane to polyrotaxane, thereby obtaining cyclodextrin / polydimethylsiloxane polyrotaxane. The range of motion of the cyclodextrin is restricted to the polydimethylsiloxane chain, preventing detachment.

[0034] Specific Embodiment 2: The difference between this embodiment and Specific Embodiment 1 is that the special coagulation bath described in step 1 consists of water and dimethylformamide, with a mass ratio of (1:8) to (8:1). The other steps and parameters are the same as in Specific Embodiment 1.

[0035] Specific Embodiment 3: The difference between this embodiment and Specific Embodiment 2 is that the cyclodextrin described in step 2 is β-cyclodextrin or γ-cyclodextrin, the polydimethylsiloxane terminal group is an aminopropyl group, and its molecular weight is 1000 to 5000 Da. The other steps and parameters are the same as in Specific Embodiment 2.

[0036] Specific Embodiment 4: The difference between this embodiment and Specific Embodiment 1 is that, regarding the saturated cyclodextrin solution described in step 2, the solvent used here is compatible with the type of cyclodextrin; if the cyclodextrin is β-cyclodextrin, the solvent is dimethylformamide, and if the cyclodextrin is γ-cyclodextrin, the solvent is water. The other steps and parameters are the same as in Specific Embodiment 1.

[0037] Specific Embodiment 5: The difference between this embodiment and Specific Embodiment 1 is that, regarding the ultrasonic treatment, shaking, and standing described in step 2, the parameters are all compatible with the type of cyclodextrin. When the cyclodextrin is β-cyclodextrin, the ultrasonic treatment power is 500-1500W, the time is 5-15min, the shaking speed is 50-100r / min, the time is 5-10d, and the standing time is 2d. When the cyclodextrin is γ-cyclodextrin, the ultrasonic treatment power is 200-600W, the time is 3-9min, the shaking speed is 50-100r / min, the time is 10-30h, and the standing time is 5-8h. The other steps and parameters are the same as in Specific Embodiment 1.

[0038] Specific Embodiment 6: The difference between this embodiment and Specific Embodiment 1 is that, for the cyclodextrin / polydimethylsiloxane pseudopolyrotaxane dispersion prepared in step 2, the solute concentration in the dispersion is 1 to 3 g / L, the solvent is dimethylformamide and distilled water, where the volume ratio of dimethylformamide to distilled water is (2:1) to (1:2), and for the preparation of the dispersion, the cyclodextrin / polydimethylsiloxane pseudopolyrotaxane is dissolved in dimethylformamide, and then distilled water is added to ensure effective dispersion. Other steps and parameters are the same as in Specific Embodiment 1.

[0039] Specific Embodiment 7: The difference between this embodiment and Specific Embodiment 1 is that the mass concentration of the glycidyl methacrylate aqueous solution described in step 3 is 1% to 3%, and the application amount is 100 μl / cm². 2 The other steps and parameters are the same as in the specific embodiment 1.

[0040] Specific Embodiment 8: The difference between this embodiment and Specific Embodiment 1 is that, regarding the ultraviolet irradiation described in step 3, the ultraviolet intensity is 3-8 mW / cm². 2 The irradiation time is 5 to 15 minutes. Other steps and parameters are the same as in the specific embodiment 1.

[0041] Specific Embodiment 9: The difference between this embodiment and Specific Embodiment 1 is that the amount of cyclodextrin / polydimethylsiloxane pseudopolyrotaxane dispersion used in step 3 is 25 ml / cm³. 2 The other steps and parameters are the same as in the specific embodiment 1.

[0042] Specific Embodiment 10: The difference between this embodiment and Specific Embodiment 1 is that, for the fluorescein-4-isothiocyanate solution described in step 3, the concentration is 2.5 to 7.5 mg / mL, and the amount used is 1.5 to 3.5 mL / cm³. 2 The other steps and parameters are the same as in the specific embodiment 1.

[0043] Specific Embodiment 11: The difference between this embodiment and Specific Embodiment 1 is that the fouling-resistant membrane based on the amphoteric dynamic supramolecular obtained in step 3 is immersed in deionized water for 24 hours, with the water being changed every 8 hours, in preparation for use. Other steps and parameters are the same as in Specific Embodiment 1.

[0044] The beneficial effects of the present invention will be verified by the following examples.

[0045] Example 1: A method for producing a fouling-resistant film based on an amphoteric dynamic supramolecular, which is carried out according to the following steps: 1. Production of high-flux polyethersulfone film: A casting solution is formed by mixing polyethersulfone, polyvinylpyrrolidone, Pluronic F127, and dimethylformamide in a mass ratio of 14:7:7:72. The mixture is then stirred at 70°C for 4 hours, allowed to stand at 70°C for 4 hours to remove air bubbles, and after the casting solution has cooled naturally to 25°C, it is applied to a glass plate to form a 250 μm thick liquid film. The film is then immersed in a special coagulation bath for 5 minutes to obtain a base film, and immersed in deionized water for ≥12 hours to prepare for use. 2. Production of hydrophilic, low-surface-energy amphoteric supramolecules: Polydimethylsiloxane is added to a saturated cyclodextrin solution, followed by sonication, shaking, and standing in sequence, and the product is precipitated. Further extraction and washing with cyclohexane, washing with distilled water, and vacuum drying are performed to obtain a hydrophilic, low-surface-energy amphoteric dynamic supramolecular, i.e., cyclodextrin / polydimethylsiloxane pseudopolyrotaxane. A cyclodextrin / polydimethylsiloxane pseudopolyrotaxane dispersion is then prepared. III. Manufacturing of a hydrophilic, low-surface-energy dynamic fouling-resistant layer: The substrate film produced in Step 1 is coated with a desalted glycidyl methacrylate aqueous solution, then irradiated with ultraviolet light under nitrogen gas protection, and further washed with deionized water to obtain film A. At room temperature, film A is immersed for 12 hours in the cyclodextrin / polydimethylsiloxane pseudopolyrotaxane dispersion prepared in step 2, and after removal, is further immersed for 3 hours in a fluorescein-4-isothiocyanate solution to obtain a hydrophilic, low-surface-energy dynamic fouling-resistant layer, i.e., a fouling-resistant film based on an amphoteric dynamic supramolecular, thus completing the manufacturing method. Here, regarding the precipitate of the product described in step 2, 90% by weight of dimethylformamide is removed by rotary evaporation, and then an equal mass of distilled water is added to induce a precipitate of β-cyclodextrin / polydimethylsiloxane pseudopolyrotaxane. Regarding the cyclodextrin / polydimethylsiloxane pseudo-polyrotaxane obtained in Step 2, here, the cyclodextrin is β-cyclodextrin, the mass input ratio of β-cyclodextrin to polydimethylsiloxane is 2.24:1, and the molar ratio of β-cyclodextrin to polydimethylsiloxane in the obtained cyclodextrin / polydimethylsiloxane pseudo-polyrotaxane is 0.13:1. The special coagulation bath described in Step 1 consists of water and dimethylformamide, and the mass ratio thereof is 1:1. The cyclodextrin described in Step 2 is β-cyclodextrin, the polydimethylsiloxane end group is an aminopropyl group, and its molecular weight is 3000 Da. Regarding the saturated cyclodextrin solution described in Step 2, here, the cyclodextrin is β-cyclodextrin and the solvent is dimethylformamide. Regarding the ultrasonic treatment, shaking, and standing described in Step 2, the ultrasonic treatment power is 900 W, the time is 15 min, the shaking speed is 50 r / min, the time is 7 d, and the standing time is 2 d.

[0046] Regarding the cyclodextrin / polydimethylsiloxane pseudo-polyrotaxane dispersion prepared in Step 2, the solute concentration in the dispersion is 2 g / L, the solvents are dimethylformamide and distilled water, here, the volume ratio of dimethylformamide to distilled water is 1:1. For the production of the dispersion, the cyclodextrin / polydimethylsiloxane pseudo-polyrotaxane is dissolved in dimethylformamide, and distilled water is added to ensure effective dispersion. The mass concentration of the glycidyl methacrylate aqueous solution described in Step 3 is 2%, and the coating amount is 100 μl / cm 2 Yes. Regarding the ultraviolet irradiation described in Step 3, the ultraviolet intensity is 5 mW / cm 2 Yes, and the irradiation time is 10 min. The amount of cyclodextrin / polydimethylsiloxane pseudopolyrotaxane dispersion to be used as described in Step 3 is 25 ml / cm³. 2 And, The fluorescein-4-isothiocyanate solution described in Step 3 has a concentration of 5 mg / mL and a usage volume of 2.5 mL / cm³. 2 And, The fouling-resistant membrane based on the amphoteric dynamic supramolecular obtained in Step 3 was immersed in deionized water for 24 hours, with the water changed every 8 hours, to prepare it for use.

[0047] In step 1 of this embodiment, the high-flux polyethersulfone film was produced by combining non-solvent-induced phase separation and surface segregation.

[0048] The substrate membrane obtained in step 1 of this embodiment had a pore size at the ultrafiltration level, and its porosity was 10% to 50% higher than that of a typical ultrafiltration membrane.

[0049] The hydrophilic, low-surface-energy amphoteric supramolecular obtained in step 1 of this embodiment is a pseudopolyrotaxane structure in which "thread-like molecules penetrate a cyclic molecule," where the cyclodextrin is the hydrophilic cyclic host and the polydimethylsiloxane is the low-surface-energy thread-like host.

[0050] The hydrophilic, low-surface-energy amphoteric supramolecule in step 2 of this embodiment was fabricated by solvent-induced self-assembly.

[0051] The purpose of UV irradiation in step 3 of this embodiment was to initiate radical polymerization and graft glycidyl methacrylate onto the substrate.

[0052] The purpose of washing with deionized water in step 3 of this embodiment was to remove unreacted glycidyl methacrylate from the base film.

[0053] In the immersion process described in step 3 of this embodiment, during the immersion in the cyclodextrin / polydimethylsiloxane pseudopolyrotaxane dispersion, an addition reaction occurs between the terminal amino groups of polydimethylsiloxane and the epoxy groups of glycidyl methacrylate, grafting both ends of most of the pseudopolyrotaxane to polyglycidyl methacrylate to form a "clothesline-shaped" structure, and converting to polyrotaxane by end capping. During the immersion in the fluorescein-4-isothiocyanate solution, the remaining amino groups are end-capped, converting almost all of the pseudopolyrotaxane to polyrotaxane, and the range of movement of the cyclodextrin is restricted to the polydimethylsiloxane chain, preventing detachment.

[0054] The fouling-resistant membrane based on the amphoteric dynamic supramolecular obtained in this example is denoted as β-CD / PDMS@M-0.13, where CD is an abbreviation for cyclodextrin, PDMS is an abbreviation for polydimethylsiloxane, @ represents the load, M is an abbreviation for membrane, and -0.13 represents a molar ratio of cyclodextrin to polydimethylsiloxane of 0.13:1.

[0055] Example 2: In step 2 of this example, the mass input ratio of β-cyclodextrin to polydimethylsiloxane was 4.82:1, and the molar ratio of β-cyclodextrin to polydimethylsiloxane in the resulting cyclodextrin / polydimethylsiloxane pseudopolyrotaxane was 0.27:1. All other aspects were the same as in Example 1. The fouling-resistant film based on the amphoteric dynamic supramolecular obtained in this example was named β-CD / PDMS@M-0.27.

[0056] Example 3: In step 2 of this example, the mass input ratio of β-cyclodextrin to polydimethylsiloxane was 7.32:1, and the molar ratio of β-cyclodextrin to polydimethylsiloxane in the resulting cyclodextrin / polydimethylsiloxane pseudopolyrotaxane was 0.40:1. All other aspects were the same as in Example 1.

[0057] The fouling-resistant film based on the amphoteric dynamic supramolecular obtained in this example was named β-CD / PDMS@M-0.40.

[0058] Example 4: In step 2 of this example, the mass input ratio of β-cyclodextrin to polydimethylsiloxane was 10.10:1, and the molar ratio of β-cyclodextrin to polydimethylsiloxane in the resulting cyclodextrin / polydimethylsiloxane pseudopolyrotaxane was 0.53:1. All other aspects were the same as in Example 1.

[0059] The fouling-resistant film based on the amphoteric dynamic supramolecular obtained in this example was named β-CD / PDMS@M-0.53.

[0060] Example 5: In step 2 of this embodiment, the cyclodextrin was γ-cyclodextrin, the solvent was water, the sonication power was 400W, the time was 5 min, the shaking rate was 50 r / min, the time was 24 h, and the standing time was 8 h. The γ-cyclodextrin / polydimethylsiloxane pseudopolyrotaxane spontaneously formed a gel-like precipitate, the mass input ratio of γ-cyclodextrin to polydimethylsiloxane was 2.45:1, and the molar ratio of γ-cyclodextrin to polydimethylsiloxane in the obtained cyclodextrin / polydimethylsiloxane pseudopolyrotaxane was 0.13:1. Everything else was the same as in Example 1.

[0061] The fouling-resistant film based on the amphoteric dynamic supramolecular obtained in this example was named γ-CD / PDMS@M-0.13.

[0062] Example 6: In step 2 of this example, the mass input ratio of γ-cyclodextrin to polydimethylsiloxane was 5.27:1, and the molar ratio of γ-cyclodextrin to polydimethylsiloxane in the resulting cyclodextrin / polydimethylsiloxane pseudopolyrotaxane was 0.27:1. All other aspects were the same as in Example 5.

[0063] The fouling-resistant film based on the amphoteric dynamic supramolecular obtained in this example was named γ-CD / PDMS@M-0.27.

[0064] Example 7: In step 2 of this example, the mass input ratio of γ-cyclodextrin to polydimethylsiloxane was 8.02:1, and the molar ratio of γ-cyclodextrin to polydimethylsiloxane in the resulting cyclodextrin / polydimethylsiloxane pseudopolyrotaxane was 0.40:1. All other aspects were the same as in Example 5.

[0065] The fouling-resistant film based on the amphoteric dynamic supramolecular obtained in this example was named γ-CD / PDMS@M-0.40.

[0066] Example 8: In step 2 of this example, the mass input ratio of γ-cyclodextrin to polydimethylsiloxane was 10.81:1, and the molar ratio of γ-cyclodextrin to polydimethylsiloxane in the resulting cyclodextrin / polydimethylsiloxane pseudopolyrotaxane was 10.81:1. All other aspects were the same as in Example 5.

[0067] The fouling-resistant film based on the amphoteric dynamic supramolecular obtained in this example was named γ-CD / PDMS@M-0.53.

[0068] Example 9: In step 2 of this example, the mass input ratio of γ-cyclodextrin to polydimethylsiloxane was 10.10:1, and the molar ratio of γ-cyclodextrin to polydimethylsiloxane in the resulting cyclodextrin / polydimethylsiloxane pseudopolyrotaxane was 13.79:1. All other aspects were the same as in Example 5.

[0069] The fouling-resistant film based on the amphoteric dynamic supramolecular obtained in this example was named γ-CD / PDMS@M-0.67.

[0070] Comparative example: In this comparative example, cyclodextrin was not added in step 2, and in step 3, polydimethylsiloxane was used directly to carry out the grafting reaction, with cyclohexane as the solvent. Otherwise, it was the same as in Example 1.

[0071] The amphoteric dynamic supramolecular fouling-resistant film obtained in this example was denoted as PDMS@M.

[0072] result: As shown in Figure 1, the flux volumes at 5°C for β-CD / PDMS@M-0.13, β-CD / PDMS@M-0.27, β-CD / PDMS@M-0.40, and β-CD / PDMS@M-0.53 obtained in Examples 1-4 were 208.4, 286.6, 379.1, and 399.8 Lm, respectively. -2 h -1 The fluxes obtained in Examples 5-9, γ-CD / PDMS@M-0.13, γ-CD / PDMS@M-0.27, γ-CD / PDMS@M-0.40, γ-CD / PDMS@M-0.53, and γ-CD / PDMS@M-0.67, at 5°C were 291.0, 340.1, 435.0, 438.4, and 445.7 Lm, respectively. -2 h -1 Therefore, the flux of PDMS@M obtained in the comparative example at 5°C was 94.4 Lm -2 h -1 That was the case.

[0073] As shown in Figure 2, the flux volumes at 20°C for β-CD / PDMS@M-0.13, β-CD / PDMS@M-0.27, β-CD / PDMS@M-0.40, and β-CD / PDMS@M-0.53 obtained in Examples 1-4 were 289.1, 408.9, 481.2, and 474.1 Lm, respectively. -2 h -1 The fluxes obtained in Examples 5-9, γ-CD / PDMS@M-0.13, γ-CD / PDMS@M-0.27, γ-CD / PDMS@M-0.40, γ-CD / PDMS@M-0.53, and γ-CD / PDMS@M-0.67, at 20°C were 405.2, 492.7, 546.2, 522.0, and 506.8 Lm, respectively. -2 h -1 Therefore, the flux of PDMS@M obtained in the comparative example at 20°C was 126.91 Lm³. -2 h -1 That was the case.

[0074] As shown in Figure 3, the flux volumes at 35°C for β-CD / PDMS@M-0.13, β-CD / PDMS@M-0.27, β-CD / PDMS@M-0.40, and β-CD / PDMS@M-0.53 obtained in Examples 1-4 were 397.6, 588.7, 618.8, and 554.0 Lm, respectively. -2 h -1 The fluxes obtained in Examples 5-9, γ-CD / PDMS@M-0.13, γ-CD / PDMS@M-0.27, γ-CD / PDMS@M-0.40, γ-CD / PDMS@M-0.53, and γ-CD / PDMS@M-0.67, at 35°C were 565.8, 735.5, 711.8, 623.6, and 612.6 Lm, respectively. -2 h -1 Therefore, the flux of PDMS@M obtained in the comparative example at 35°C was 148.7 Lm -2 h -1 That was the case.

[0075] As shown in Figure 4, the flux volumes at 50°C for β-CD / PDMS@M-0.13, β-CD / PDMS@M-0.27, β-CD / PDMS@M-0.40, and β-CD / PDMS@M-0.53 obtained in Examples 1-4 were 479.0, 691.6, 693.7, and 646.5 Lm, respectively. -2 h -1 The flux volumes at 50°C for γ-CD / PDMS@M-0.13, γ-CD / PDMS@M-0.27, γ-CD / PDMS@M-0.40, γ-CD / PDMS@M-0.53, and γ-CD / PDMS@M-0.67 obtained in Examples 5-9 were 725.8, 887.1, 860.7, 777.0, and 696.0 Lm, respectively. -2 h -1 Therefore, the flux of PDMS@M obtained in the comparative example at 50°C was 181.2 Lm -2 h -1 That was the case.

[0076] As can be seen by comparing Figures 1 to 4, the dynamism of cyclodextrin / polydimethylsiloxane pseudopolyrotaxane is advantageous for improving membrane flux. Overall, the flux of γ-CD / PDMS@M was higher than that of β-CD / PDMS@M, and the most advantageous conditions for improving flux were when the mass ratio of cyclodextrin to polydimethylsiloxane in the cyclodextrin / polydimethylsiloxane pseudopolyrotaxane was 0.27 and 0.4.

[0077] As shown in Figure 5, the inhibition rates against BSA for β-CD / PDMS@M-0.13, β-CD / PDMS@M-0.27, β-CD / PDMS@M-0.40, and β-CD / PDMS@M-0.53 obtained in Examples 1-4, γ-CD / PDMS@M-0.13, γ-CD / PDMS@M-0.27, γ-CD / PDMS@M-0.40, γ-CD / PDMS@M-0.53, and γ-CD / PDMS@M-0.67 obtained in Examples 5-9, and PDMS@M obtained in the comparative example were all slightly higher than 99%. This inhibition rate was mainly determined by the pore size of the substrate and had no significant relationship with the modifier.

[0078] As shown in Figure 6, the flux decay rates of β-CD / PDMS@M-0.13, β-CD / PDMS@M-0.27, β-CD / PDMS@M-0.40, and β-CD / PDMS@M-0.53 obtained in Examples 1-4 were 32.9%, 28.8%, 25.2%, and 26.5%, respectively, and the flux recovery rates were 95.1%, 97.2%, 99.3%, and 97.7%, respectively. The flux recovery rates of γ-CD / PDMS@M-0.13 and γ-CD / PDMS obtained in Examples 5-9 were 32.9%, 28.8%, 25.2%, and 26.5%, respectively. The flux decay rates for @M-0.27, γ-CD / PDMS@M-0.40, γ-CD / PDMS@M-0.53, and γ-CD / PDMS@M-0.67 were 24.7%, 14.2%, 16.4%, 22.5%, and 27.2%, respectively, and the flux recovery rates were 97.3%, 99.7%, 99.5%, 98.1%, and 96.4%, respectively. In comparison, the flux decay rate for PDMS@M obtained was 34.3%, and the flux recovery rate was 93.6%. As the analysis shows, the dynamism of the cyclodextrin / polydimethylsiloxane pseudopolyrotaxane is advantageous for improving the membrane's fouling resistance. Overall, the fouling resistance of γ-CD / PDMS@M was higher than that of β-CD / PDMS@M. For β-CD / PDMS@M, the optimal fouling resistance was found when the mass ratio of cyclodextrin to polydimethylsiloxane in the cyclodextrin / polydimethylsiloxane pseudopolyrotaxane was 0.4, and for γ-CD / PDMS@M, the optimal fouling resistance was found when the mass ratio of cyclodextrin to polydimethylsiloxane in the cyclodextrin / polydimethylsiloxane pseudopolyrotaxane was 0.27.

[0079] As shown in Figure 7, the β-CD / PDMS@M-0.40 and γ-CD / PDMS@M-0.27 obtained in Examples 3 and 6 were applicable in a pH range of 3 to 11, and showed stronger fouling resistance under alkaline conditions (pH=9, 11) or BSA isoelectric point conditions (pH=5). The former was due to the stronger interaction between cyclodextrin and water molecules and better dynamism in an alkaline environment, while the latter was due to the weaker BSA adsorption capacity under isoelectric point conditions.

[0080] As shown in Figure 8, β-CD / PDMS@M-0.40 and γ-CD / PDMS@M-0.27 obtained in Examples 3 and 6 still exhibited excellent fouling resistance even at low stirring speeds. At stirring speeds of 120 rpm or higher, γ-CD / PDMS@M-0.27 achieved the best fouling resistance, while at stirring speeds of 180 rpm or higher, β-CD / PDMS@M-0.40 achieved the best fouling resistance.

[0081] As shown in Figure 9, β-CD / PDMS@M-0.40 and γ-CD / PDMS@M-0.27 obtained in Examples 3 and 6 were able to maintain excellent fouling resistance within the range of 5°C to 50°C, and the fouling resistance remained almost constant within the range of 5°C to 35°C. This is because temperature synchronously improved the mobility of cyclodextrin / polydimethylsiloxane polyrotaxane, the activity of water, and the fouling tendency of foulants, and all three reached an equilibrium state within a certain range.

[0082] As shown in Figures 10 and 11, the β-CD / PDMS@M-0.40 and γ-CD / PDMS@M-0.27 obtained in Examples 3 and 6 exhibited universal fouling resistance to various foulants, where flux attenuation due to the separation of sodium alginate was greatest, followed by bovine serum albumin and emulsified hexadecane, and least for yeast and humic acid.

[0083] In summary, the fouling-resistant membrane based on the amphoteric dynamic supramolecular material manufactured in this embodiment has good fouling resistance, adapts to different flow rates and temperature conditions, has high flux and low decay rate, and is applicable to various water treatment processes. The overall performance of the membrane can be precisely adjusted and controlled by adjusting the membrane manufacturing parameters. For example, different types of cyclodextrin have different dynamic properties. Within the scope of this embodiment, the dynamics of γ-cyclodextrin / polydimethylsiloxane pseudopolyrotaxane are superior to those of β-cyclodextrin / polydimethylsiloxane pseudopolyrotaxane. Therefore, γ-CD / PDMS@M has overall higher flux and better fouling resistance. By adjusting and controlling the ratio, precise optimization of the overall performance of the membrane can be achieved. For β-CD / PDMS@M, the best overall performance is achieved when the mass ratio of cyclodextrin to polydimethylsiloxane in the cyclodextrin / polydimethylsiloxane pseudopolyrotaxane is 0.4, and for γ-CD / PDMS@M, the best overall performance is achieved when the mass ratio of cyclodextrin to polydimethylsiloxane in the cyclodextrin / polydimethylsiloxane pseudopolyrotaxane is 0.27.

[0084] The above description of the present invention has been accompanied by drawings, but the present invention is not limited to the above-described specific embodiments; the above-described specific embodiments are merely illustrative and not limiting. Those skilled in the art can make many modifications based on the suggestions of the present invention without departing from the spirit of the invention, and all of these will fall within the scope of protection of the present invention.

Claims

1. A method for producing a fouling-resistant film based on an amphoteric dynamic supramolecular, which is carried out according to the following steps:

1. Production of high-flux polyethersulfone substrate films: A casting solution is formed by mixing polyethersulfone, polyvinylpyrrolidone, Pluronic F127, and dimethylformamide in a mass ratio of 14:7:7:

72. The mixture is then stirred at 70°C for 4 hours, allowed to stand at 70°C for 4 hours to remove bubbles, and after the casting solution has cooled naturally to 25°C, it is applied to a glass plate to form a 250 μm thick liquid film. This film is then immersed in a special coagulation bath for 5 minutes to obtain a base film, and immersed in deionized water for ≥12 hours to prepare for use.

2. Production of hydrophilic-low surface energy amphoteric supramolecules: Polydimethylsiloxane is added to a saturated cyclodextrin solution, followed by sonication, shaking, and standing in sequence, and the product is precipitated. Further extraction and washing with cyclohexane, washing with distilled water, and vacuum drying are performed to obtain a hydrophilic, low-surface-energy amphoteric dynamic supramolecular, i.e., cyclodextrin / polydimethylsiloxane pseudopolyrotaxane. A cyclodextrin / polydimethylsiloxane pseudopolyrotaxane dispersion is then prepared. III. Manufacturing of a hydrophilic, low-surface-energy dynamic fouling-resistant layer: In step 1, a desalted aqueous solution of glycidyl methacrylate is applied to the substrate film, and then the film is irradiated with ultraviolet light under nitrogen gas protection, and further washed with deionized water to obtain film A. At room temperature, film A is immersed for 12 hours in the cyclodextrin / polydimethylsiloxane pseudopolyrotaxane dispersion prepared in step 2, and after removal, is further immersed for 3 hours in a fluorescein-4-isothiocyanate solution to obtain a hydrophilic, low-surface-energy dynamic fouling-resistant layer, i.e., a fouling-resistant film based on an amphoteric dynamic supramolecular, thus completing the manufacturing method. Here, regarding the precipitation of the product described in step 2, the precipitation method is appropriate to the type of cyclodextrin. If the cyclodextrin is β-cyclodextrin, 60% to 90% by weight of dimethylformamide is removed by rotary evaporation, and an equal mass of distilled water is added to induce precipitation of β-cyclodextrin / polydimethylsiloxane pseudopolyrotaxane. If the cyclodextrin is γ-cyclodextrin, the γ-cyclodextrin / polydimethylsiloxane pseudopolyrotaxane spontaneously forms a gel-like precipitate. Regarding the cyclodextrin / polydimethylsiloxane pseudopolyrotaxane obtained in Step 2, the molar ratio of cyclodextrin to polydimethylsiloxane is determined by the type of cyclodextrin and the mass input ratio of cyclodextrin to polydimethylsiloxane. When the cyclodextrin is β-cyclodextrin, the mass input ratio of β-cyclodextrin to polydimethylsiloxane is (2.24–10.10):1, and the molar ratio of β-cyclodextrin to polydimethylsiloxane in the resulting cyclodextrin / polydimethylsiloxane pseudopolyrotaxane is (0.13–0.53):

1. A method for producing a fouling-resistant film based on an amphoteric dynamic supramolecular, characterized in that, when the cyclodextrin is γ-cyclodextrin, the mass input ratio of γ-cyclodextrin to polydimethylsiloxane is (2.45 to 13.78):1, and the molar ratio of γ-cyclodextrin to polydimethylsiloxane in the obtained cyclodextrin / polydimethylsiloxane pseudopolyrotaxane is (0.13 to 0.67):

1.

2. The method for producing a fouling-resistant film based on an amphoteric dynamic supramolecular according to claim 1, characterized in that the special coagulation bath described in step 1 consists of water and dimethylformamide, and the mass ratio thereof is (1:8) to (8:1).

3. The method for producing a fouling-resistant film based on an amphoteric dynamic supramolecular according to claim 1, characterized in that the cyclodextrin described in step 2 is β-cyclodextrin or γ-cyclodextrin, the polydimethylsiloxane terminal group is an aminopropyl group, and its molecular weight is 1000 to 5000 Da.

4. The method for producing a fouling-resistant film based on an amphoteric dynamic supramolecular according to claim 1, wherein the solvent used in the saturated cyclodextrin solution described in step 2 is compatible with the type of cyclodextrin, and when the cyclodextrin is β-cyclodextrin, the solvent is dimethylformamide, and when the cyclodextrin is γ-cyclodextrin, the solvent is water.

5. The method for producing a fouling-resistant film based on an amphoteric dynamic supramolecular as described in Step 1, characterized in that the parameters for the ultrasonic treatment, shaking, and standing described in Step 2 are all compatible with the type of cyclodextrin, and when the cyclodextrin is β-cyclodextrin, the ultrasonic treatment power is 500 to 1500 W, the time is 5 to 15 min, the shaking speed is 50 to 100 r / min, the time is 5 to 10 d, and the standing time is 2 d; when the cyclodextrin is γ-cyclodextrin, the ultrasonic treatment power is 200 to 600 W, the time is 3 to 9 min, the shaking speed is 50 to 100 r / min, the time is 10 to 30 h, and the standing time is 5 to 8 h.

6. The method for producing a fouling-resistant film based on an amphoteric dynamic supramolecular, as described in claim 1, is characterized in that the cyclodextrin / polydimethylsiloxane pseudopolyrotaxane dispersion prepared in step 2 has a solute concentration of 1 to 3 g / L, the solvents are dimethylformamide and distilled water, the volume ratio of dimethylformamide to distilled water is (2:1) to (1:2), and the dispersion is prepared by dissolving the cyclodextrin / polydimethylsiloxane pseudopolyrotaxane in dimethylformamide and then adding distilled water to ensure effective dispersion.

7. The mass concentration of the glycidyl methacrylate aqueous solution described in Step 3 is 1% to 3%, and the application amount is 100 μl / cm². ２ A method for producing a fouling-resistant film based on an amphoteric dynamic supramolecular as described in claim 1.

8. Regarding the UV irradiation described in Step 3, the UV intensity is 3-8 mW / cm². ２ The method for producing a fouling-resistant film based on an amphoteric dynamic supramolecular as described in claim 1, wherein the irradiation time is 5 to 15 mins.

9. The amount of cyclodextrin / polydimethylsiloxane pseudopolyrotaxane dispersion to be used as described in Step 3 is 25 ml / cm³. ２ The fluorescein-4-isothiocyanate solution described in step 3 has a concentration of 2.5 to 7.5 mg / mL, and the amount used is 1.5 to 3.5 mL / cm³. ２ A method for producing a fouling-resistant film based on an amphoteric dynamic supramolecular as described in claim 1.

10. A method for producing a fouling-resistant membrane based on an amphoteric dynamic supramolecular according to claim 1, characterized in that the fouling-resistant membrane based on an amphoteric dynamic supramolecular obtained in step 3 is immersed in deionized water for 24 hours, the water is changed every 8 hours, and the membrane is prepared for use.

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