A hydrophilic and antifouling polyethersulfone hollow fiber membrane, its preparation method and application

Abstract

A hydrophilic and antifouling polyethersulfone hollow fiber membrane, its preparation method, and its applications belong to the field of polymer separation membrane material technology. The process includes: 1) Casting solution preparation: dissolving polyethersulfone in N,N-dimethylacetamide, adding polyethylene glycol 400, polyvinylpyrrolidone, Tween 60, and N,N-methylenebisacrylamide to prepare the casting solution; 2) Spinning: extruding the casting solution and core solution through a spinneret, and solidifying them in a coagulation bath to form hollow fiber membrane filaments; 3) Hydrophilic modification: first immersing the hollow fiber membrane filaments in a hydrophilic modification solution, then subjecting them to a microwave crosslinking reaction in a microwave radiation chamber, and finally drying them in a hot air chamber to remove surface moisture. This hollow fiber membrane exhibits excellent comprehensive performance, combining low contact angle, high pure water flux, and excellent antifouling ability. The hydrophilic modification is uniform and thorough, improving product reliability. It can be produced continuously in an integrated manner with low production costs, and is widely used in household water purification, seawater desalination, and industrial wastewater treatment.

Description

Technical Field

[0001] This invention belongs to the field of polymer separation membrane material technology, specifically a hydrophilic and antifouling polyethersulfone hollow fiber membrane, its preparation method, and its application. Background Technology

[0002] Hollow fiber separation membranes refer to a membrane technology used for separating, filtering, and concentrating liquids. The working principle is to separate different components in a solution through tiny pores on the membrane. When pressure is applied to the membrane, solutes in the solution (such as macromolecules, suspended solids, or bacteria) are trapped by the pores on the membrane, while water molecules can pass through these pores to achieve separation and concentration.

[0003] Polyethersulfone (PES) is a high-performance hollow fiber ultrafiltration membrane material due to its high-temperature resistance, good chemical stability, and excellent mechanical strength. It has been widely applied in various fields, including electronics, pharmaceuticals, electrophoretic coatings, beverages, food chemicals, medical treatment, and wastewater treatment and recycling. However, despite its advantages, PES hollow fiber ultrafiltration membranes suffer from strong surface hydrophobicity, leading to the easy adsorption of charged pollutants onto the membrane surface and resulting in membrane fouling. This degrades membrane performance and shortens its lifespan. Therefore, developing a highly hydrophilic, high-flux, and fouling-resistant PES hollow fiber membrane has become an important research direction recently.

[0004] Existing technologies modify the hydrophilicity of polyethersulfone (PES) hollow fiber ultrafiltration membranes through chemical or physical modification of the PES surface, or by introducing hydrophilic additives into the PES material. Specifically, this involves: 1. grafting hydrophilic functional groups onto the membrane surface for chemical modification; 2. blending PES with hydrophilic polymers to form a stable blend system, thereby achieving bulk physical modification. However, most of these methods suffer from drawbacks such as complex manufacturing processes, high material costs, and stringent process requirements, hindering large-scale industrial production and thus limiting the application of PES hollow fiber ultrafiltration membranes. Summary of the Invention

[0005] In view of the above-mentioned problems in the prior art, the purpose of this invention is to design and provide a technical solution for a hydrophilic antifouling polyethersulfone hollow fiber membrane, its preparation method and application. The membrane product has excellent comprehensive performance, with low contact angle, high pure water flux and excellent antifouling ability. The hydrophilic modification is uniform and thorough, which improves the reliability of the product. It can be produced continuously in an integrated manner with low production cost. It can be widely used in household water purification, seawater desalination, industrial wastewater treatment and other fields.

[0006] The method for preparing a hydrophilic, antifouling polyethersulfone hollow fiber membrane is characterized by comprising the following steps:

[0007] 1) Preparation of casting solution: At 55-65℃, dissolve 15-20wt% polyethersulfone in 50-60wt% N,N-dimethylacetamide. After the polyethersulfone is evenly dissolved, add 5-15wt% polyethylene glycol 400, 2-8wt% polyvinylpyrrolidone, 0.5-3wt% Tween 60, and 0.5-1.2wt% N,N-methylenebisacrylamide. Continue to dissolve until it is clear and transparent. Then, degas online to obtain the casting solution and lower the temperature of the casting solution to 25-35℃.

[0008] 2) Spinning and forming: The above casting solution and core solution are extruded through a spinneret and solidified in a coagulation bath to form hollow fiber membrane filaments;

[0009] 3) Hydrophilic modification: First, the hollow fiber membrane fibers are soaked in a hydrophilic modification solution for 1-5 minutes. The hydrophilic modification solution is an aqueous solution of acrylic acid with a neutralization degree of 50-70 wt%, specifically composed of: 20-40 wt% acrylic acid, 1-4 wt% sodium hydroxide, 0.02-1 wt% potassium persulfate, 0.1-0.5 wt% N,N-methylenebisacrylamide, 1-5 wt% Tween 60 and 1-2 wt% Tween 61. Then, the membrane is placed in a microwave radiation chamber for 40-80 seconds for microwave crosslinking reaction, and then placed in a hot air chamber at 50-80℃ to dry and remove surface moisture, thus obtaining a hydrophilic antifouling polyethersulfone hollow fiber membrane.

[0010] The method for preparing a hydrophilic and antifouling polyethersulfone hollow fiber membrane is characterized in that, in step 1), the polyethersulfone has a weight-average molecular weight of 50,000-70,000 and is in powder form; the dissolution temperature is 60-62℃; the concentration of polyethersulfone is 16-18wt%, the concentration of N,N-dimethylacetamide is 54-57wt%, the concentration of polyethylene glycol 400 is 8-10wt%, the concentration of polyvinylpyrrolidone is 4-6wt%, the concentration of Tween 60 is 1-2wt%, the concentration of N,N-methylenebisacrylamide is 0.5-1.2wt%, and the temperature of the casting solution is reduced to 28-30℃.

[0011] The method for preparing a hydrophilic and antifouling polyethersulfone hollow fiber membrane is characterized in that, in step 2), the casting solution and core solution are extruded through a spinneret to form a hollow fiber membrane preform, which is then passed through an air section of 10-30cm and enters a coagulation bath to induce phase separation and solidify to form hollow fiber membrane filaments. Then, the preforms are circulated and cleaned in a water bath at 5-15℃ to remove residual pore-forming agents and solvents and are then dried on the surface.

[0012] The method for preparing a hydrophilic and antifouling polyethersulfone hollow fiber membrane is characterized in that, in step 3), the specific composition of the acrylic acid aqueous solution is: 25-30 wt% acrylic acid, 2-3 wt% sodium hydroxide, 1-0.5 wt% potassium persulfate, 0.2-0.3 wt% N,N-methylenebisacrylamide, 2-4 wt% Tween 60 and 1.2-1.5 wt% Tween 61.

[0013] The method for preparing a hydrophilic and antifouling polyethersulfone hollow fiber membrane is characterized in that, in step 3), a circulating soaking is used so that the surface and interior of the hollow fiber membrane filaments are covered with a hydrophilic modification liquid.

[0014] The method for preparing a hydrophilic and antifouling polyethersulfone hollow fiber membrane is characterized in that, in step 3), the power of the microwave radiation box is 2000-3000MHz, the microwave time is 50-60 seconds, and the temperature of the hot air box is 60-70℃.

[0015] The method for preparing a hydrophilic and antifouling polyethersulfone hollow fiber membrane is characterized in that the core liquid is a mixture of N,N-dimethylacetamide and water, with the water content being 10-30 wt%; and the coagulation bath is a mixture of water and N,N-dimethylacetamide, with the N,N-dimethylacetamide content being 0-50 wt%.

[0016] The hydrophilic and antifouling polyethersulfone hollow fiber membrane prepared by the method described in this invention.

[0017] The hydrophilic and antifouling polyethersulfone hollow fiber membrane prepared by the method described in this invention can be used in household water purification, seawater desalination, and industrial wastewater treatment.

[0018] The hydrophilic and antifouling polyethersulfone hollow fiber membrane prepared by this invention can achieve ultra-high self-hydrophilization, and water droplets can achieve ultra-fast wetting on the membrane surface. Unlike the process of adding hydrophilic agents during the preparation of the casting solution, which results in loss, the hydrophilicity of this invention through subsequent coating radiation crosslinking has higher stability, more thorough hydrophilization, and does not affect the formation of the membrane pore structure.

[0019] This invention uses sodium hydroxide as a catalyst, requiring precise control of the neutralization degree of the modification solution between 50-70%. If the sodium hydroxide concentration is too high, it can easily damage the structure of the polyethersulfone. However, if the sodium hydroxide concentration is too low, it cannot catalyze the cross-linking of acrylic acid and acrylamide to form a strong cross-linked network, ultimately resulting in a stable and robust hydrophilic network, thus leading to poor modification effects. The hydrophilically modified polyethersulfone hollow fiber ultrafiltration membrane prepared by this invention exhibits strong hydrophilicity, strong negative charge, strong fouling resistance, and high flux and organic matter rejection.

[0020] Compared with existing blending and surface post-treatment coating technologies, this invention has the following characteristics and beneficial effects:

[0021] This invention pre-adds a low concentration of the crosslinking agent N,N-methylenebisacrylamide to the polyethersulfone solution. This does not affect the film formation or structural regulation of the polyethersulfone, but provides robust membrane surface sites for subsequent hydrophilic modification of the acrylic acid crosslinking network system. After the polyethersulfone hollow fiber membrane is formed, it is continuously immersed in an aqueous acrylic acid solution. Under the action of the surfactant Tween, acrylic acid and bisacrylamide can accumulate on the membrane surface, forming a stable aqueous film. Then, under microwave radiation, highly stable crosslinking is achieved, ultimately endowing the membrane with hydrophilicity and antifouling properties. In this invention, the application of Tween significantly improves the accumulation of acrylic acid and bisacrylamide on the membrane surface, solving the problem of the difficulty in stabilizing the hydrophilic agent on the membrane surface in general coating schemes. Furthermore, the continued addition of N,N-methylenebisacrylamide to the acrylic acid aqueous solution can improve the crosslinking effect, preventing or solving the problem of insufficient crosslinking agent added to the membrane body previously. This invention innovatively utilizes the continuous hydrophilic modification method of adding acrylic acid during the spinning process, which has the advantages of simple process, simple formulation and high controllability. The polyethersulfone hollow fiber membrane obtained by this method has the advantages of high hydrophilicity and uniform distribution, and can be widely used in industrial production. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the preparation process of the hollow fiber membrane in this invention. Detailed Implementation

[0023] The present invention will now be clearly and completely described with reference to specific embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention are within the scope of protection of the present invention.

[0024] Example 1

[0025] 1) At 55°C, 15 wt% of polyethersulfone with a molecular weight of 50,000 was dissolved in 60 wt% N,N-dimethylacetamide. After the polyethersulfone was dissolved evenly, 5 wt% of polyethylene glycol 400, 2 wt% of polyvinylpyrrolidone, 0.5 wt% of Tween 60 and 0.5 wt% of N,N-methylenebisacrylamide were added. The dissolution was continued for a certain period of time until it was pure and transparent. Then, the casting solution was degassed online to obtain the casting solution, and the temperature of the casting solution was reduced to 25°C.

[0026] 2) The above casting solution and the core solution composed of 10wt% N,N-dimethylacetamide and 90wt% water are extruded through a spinneret to form a hollow fiber membrane preform. After passing through a 10cm air section, it enters a 5% N,N-dimethylacetamide aqueous solution to induce phase separation and solidify to form hollow fiber membrane filaments. Then, it enters a 5°C water bath for circulating cleaning to remove residual pore-forming agents and solvents and the surface is dried.

[0027] 3) Clean hollow fiber membrane fibers are guided to a hydrophilic modification solution. The hydrophilic modification solution formulation is: 20wt% acrylic acid, 1wt% sodium hydroxide, 0.02wt% potassium persulfate, 0.1wt% N,N-methylenebisacrylamide, 1wt% Tween 60 and 1wt% Tween 61, and 77.88wt% deionized water. After 1 minute of cyclic soaking to ensure that both the surface and interior are covered with the hydrophilic agent, the membrane is then subjected to a 40-second microwave crosslinking reaction in a 2000MHz microwave radiation chamber. Finally, it is dried in a 50℃ hot air chamber to remove surface moisture, resulting in a hydrophilic and antifouling hollow fiber polyethersulfone membrane material.

[0028] The hydrophilic modified polyethersulfone hollow fiber membrane was characterized in terms of performance. Its main performance parameters are: membrane fiber contact angle of 20-35°, pure water flux of about 650 LMH / bar@25°C, and flux recovery rate of 96% after anti-bovine serum albumin adhesion.

[0029] Example 2

[0030] At 56°C, 15 wt% of polyethersulfone with a molecular weight of 70,000 was dissolved in 57 wt% N,N-dimethylacetamide. After the polyethersulfone was dissolved evenly, 7 wt% polyethylene glycol 400, 3 wt% polyvinylpyrrolidone, 1 wt% Tween 60 and 0.6 wt% N,N-methylenebisacrylamide were added. The dissolution was continued for a certain period of time until it was pure and transparent. Then, the casting solution was obtained by online degassing and the temperature of the casting solution was reduced to 28°C.

[0031] 2) The above casting solution and the core solution composed of 10wt% N,N-dimethylacetamide and 90wt% water are extruded through a spinneret to form a hollow fiber membrane preform. After passing through a 15cm air section, it enters deionized water to induce phase separation and solidify to form hollow fiber membrane filaments. Then, it enters an 8°C water bath for circulating cleaning to remove residual pore-forming agents and solvents and is then dried on the surface.

[0032] 3) Clean hollow fiber membrane fibers are guided to a hydrophilic modification solution. The hydrophilic modification solution formulation is: 20wt% acrylic acid, 1wt% sodium hydroxide, 0.02wt% potassium persulfate, 0.1wt% N,N-methylenebisacrylamide, 1wt% Tween 60 and 2wt% Tween 61, and 75.97wt% deionized water. After 2 minutes of cyclic soaking to ensure that both the surface and interior are covered with the hydrophilic agent, the membrane is then subjected to a 60-second microwave crosslinking reaction in a 2200MHz microwave radiation chamber. Finally, it is dried in a 55℃ hot air chamber to remove surface moisture, resulting in a hydrophilic and antifouling hollow fiber polyethersulfone membrane material.

[0033] The hydrophilic modified polyethersulfone hollow fiber membrane was characterized in terms of its main performance parameters: the contact angle of the membrane fibers was 40-55°, the pure water flux was about 1000 LMH / bar@25℃, and the flux recovery rate after anti-bovine serum albumin adhesion reached 94%.

[0034] Example 3

[0035] At 60°C, 18 wt% of polyethersulfone with a molecular weight of 70,000 was dissolved in 54 wt% N,N-dimethylacetamide. After the polyethersulfone was dissolved evenly, 10 wt% of polyethylene glycol 400, 4 wt% polyvinylpyrrolidone, 1.5 wt% Tween 60, and 0.8 wt% N,N-methylenebisacrylamide were added. The dissolution was continued for a certain period of time until it was pure and transparent. Then, the casting solution was obtained by online degassing and the temperature of the casting solution was reduced to 30°C.

[0036] 2) The above casting solution and the core solution composed of 20wt% N,N-dimethylacetamide and 80wt% water are extruded through a spinneret to form a hollow fiber membrane preform. After passing through a 20cm air section, the preform enters a 25% N,N-dimethylacetamide aqueous solution to induce phase separation and solidify, forming hollow fiber membrane filaments. Then, the preforms are placed in a 10°C water bath for circulating cleaning to remove residual pore-forming agents and solvents, and the surface is dried.

[0037] 3) Clean hollow fiber membrane fibers are guided to a hydrophilic modification solution. The hydrophilic modification solution formulation is: 30wt% acrylic acid, 2wt% sodium hydroxide, 0.3wt% potassium persulfate, 0.3wt% N,N-methylenebisacrylamide, 3wt% Tween 60 and 1.5wt% Tween 61, and 62.9wt% deionized water. After 3 minutes of cyclic soaking to ensure that both the surface and interior are covered with the hydrophilic agent, the membrane is then subjected to a 60-second microwave crosslinking reaction in a 2500MHz microwave radiation chamber. Finally, it is dried in a 65℃ hot air chamber to remove surface moisture, resulting in a hydrophilic and antifouling hollow fiber polyethersulfone membrane material.

[0038] The hydrophilic modified polyethersulfone hollow fiber membrane was characterized in terms of its main performance parameters: the contact angle of the membrane fibers was 30-40°, the pure water flux was about 800 LMH / bar@25℃, and the flux recovery rate after anti-bovine serum albumin adhesion reached 95%.

[0039] Example 4

[0040] At 63°C, 16 wt% of polyethersulfone with a molecular weight of 60,000 was dissolved in 56 wt% N,N-dimethylacetamide. After the polyethersulfone was dissolved evenly, 12 wt% polyethylene glycol 400, 5 wt% polyvinylpyrrolidone, 2 wt% Tween 60 and 1 wt% N,N-methylenebisacrylamide were added. The dissolution was continued for a certain period of time until it was pure and transparent. Then, the casting solution was obtained by online degassing and the temperature of the casting solution was reduced to 33°C.

[0041] 2) The above casting solution and the core solution composed of 25wt% N,N-dimethylacetamide and 75wt% water are extruded through a spinneret to form a hollow fiber membrane preform. After passing through a 25cm air section, the preform enters a 35% N,N-dimethylacetamide aqueous solution to induce phase separation and solidify, forming hollow fiber membrane filaments. Then, the preforms are placed in a 12°C water bath for circulating cleaning to remove residual pore-forming agents and solvents, and the surface is dried.

[0042] 3) Clean hollow fiber membrane fibers are guided to a hydrophilic modification solution. The hydrophilic modification solution formulation is: 35wt% acrylic acid, 3wt% sodium hydroxide, 0.6wt% potassium persulfate, 0.4wt% N,N-methylenebisacrylamide, 4wt% Tween 60 and 1.8wt% Tween 61, and 55.2wt% deionized water. After 4 minutes of cyclic soaking to ensure that both the surface and interior are covered with the hydrophilic agent, the membrane is then subjected to a 70-second microwave crosslinking reaction in a 2800MHz microwave radiation chamber. Finally, it is dried in a 70℃ hot air chamber to remove surface moisture, resulting in a hydrophilic and antifouling hollow fiber polyethersulfone membrane material.

[0043] The hydrophilic modified polyethersulfone hollow fiber membrane was characterized in terms of its main performance parameters: the contact angle of the membrane fibers was 20-30°, the pure water flux was about 900 LMH / bar@25℃, and the flux recovery rate after anti-bovine serum albumin adhesion reached 97%.

[0044] Example 5

[0045] At 64°C, 19 wt% of polyethersulfone with a molecular weight of 65,000 was dissolved in 52 wt% N,N-dimethylacetamide. After the polyethersulfone was dissolved evenly, 14 wt% of polyethylene glycol 400, 6 wt% of polyvinylpyrrolidone, 2.5 wt% of Tween 60, and 1.1 wt% of N,N-methylenebisacrylamide were added. The dissolution was continued for a certain period of time until it was pure and transparent. Then, the casting solution was obtained by online degassing and the temperature of the casting solution was reduced to 34°C.

[0046] 2) The above casting solution and the core solution composed of 30wt% N,N-dimethylacetamide and 70wt% water are extruded through a spinneret to form a hollow fiber membrane preform. After passing through a 25cm air section, it enters a 45% N,N-dimethylacetamide aqueous solution to induce phase separation and solidify to form hollow fiber membrane filaments. Then, it enters a 14°C water bath for circulating cleaning to remove residual pore-forming agents and solvents and the surface is dried.

[0047] 3) Clean hollow fiber membrane fibers are drawn and transported to a hydrophilic modification solution. The hydrophilic modification solution formulation is: 38wt% acrylic acid, 3.5wt% sodium hydroxide, 0.8wt% potassium persulfate, 0.45wt% N,N-methylenebisacrylamide, 4.5wt% Tween 60 and 1.9wt% Tween 61, and 50.85wt% deionized water. After 4 minutes of cyclic soaking to ensure that both the surface and interior are covered with the hydrophilic agent, the membrane is then subjected to a 65-second microwave crosslinking reaction in a 2800MHz microwave radiation chamber. Finally, it is dried in a 75℃ hot air chamber to remove surface moisture, resulting in a hydrophilic and antifouling hollow fiber polyethersulfone membrane material.

[0048] The hydrophilic modified polyethersulfone hollow fiber membrane was characterized in terms of its main performance parameters: the contact angle of the membrane fibers was 35-45°, the pure water flux was about 850 LMH / bar@25℃, and the flux recovery rate after anti-bovine serum albumin adhesion reached 92%.

[0049] Example 6

[0050] At 65°C, 20 wt% of polyethersulfone with a molecular weight of 70,000 was dissolved in 50 wt% N,N-dimethylacetamide. After the polyethersulfone was dissolved evenly, 15 wt% polyethylene glycol 400, 8 wt% polyvinylpyrrolidone, 3 wt% Tween 60 and 1.2 wt% N,N-methylenebisacrylamide were added. The dissolution was continued for a certain period of time until it was pure and transparent. Then, the casting solution was obtained by online degassing and the temperature of the casting solution was reduced to 35°C.

[0051] 2) The above casting solution and the core solution composed of 30wt% N,N-dimethylacetamide and 70wt% water are extruded through a spinneret to form a hollow fiber membrane preform. After passing through a 30cm air section, it enters a 50% N,N-dimethylacetamide aqueous solution to induce phase separation and solidify to form hollow fiber membrane filaments. Then, it enters a 15°C water bath for circulating cleaning to remove residual pore-forming agents and solvents and the surface is dried.

[0052] 3) Clean hollow fiber membrane fibers are guided to a hydrophilic modification solution. The hydrophilic modification solution consists of 40 wt% acrylic acid, 4 wt% sodium hydroxide, 1 wt% potassium persulfate, 0.5 wt% N,N-methylenebisacrylamide, 5 wt% Tween 60 and 2 wt% Tween 61, and 47.5 wt% deionized water. After 4 minutes of cyclic soaking to ensure both the surface and interior are covered with the hydrophilic agent, the membrane is then subjected to an 80-second microwave crosslinking reaction in a 3000MHz microwave radiation chamber. Finally, it is dried in an 80°C hot air chamber to remove surface moisture, resulting in a hydrophilic and antifouling hollow fiber polyethersulfone membrane material.

[0053] The hydrophilic modified polyethersulfone hollow fiber membrane was characterized in terms of its main performance parameters: the contact angle of the membrane fibers was 20-35°, the pure water flux was about 750 LMH / bar@25℃, and the flux recovery rate after anti-bovine serum albumin adhesion reached 95%.

[0054] This invention is not limited to the preferred embodiments described above. Anyone can derive other products in various forms under the guidance of this invention. However, regardless of any changes in shape or structure, any technical solution that is the same as or similar to this application falls within the protection scope of this invention.

Claims

1. A method for preparing a hydrophilic, antifouling polyethersulfone hollow fiber membrane, characterized in that... Includes the following steps: 1) Preparation of casting solution: At 55-65℃, dissolve 15-20wt% polyethersulfone in 50-60wt% N,N-dimethylacetamide. After the polyethersulfone is evenly dissolved, add 5-15wt% polyethylene glycol 400, 2-8wt% polyvinylpyrrolidone, 0.5-3wt% Tween 60, and 0.5-1.2wt% N,N-methylenebisacrylamide. Continue to dissolve until it is clear and transparent. Then, degas online to obtain the casting solution and lower the temperature of the casting solution to 25-35℃. 2) Spinning and forming: The above casting solution and core solution are extruded through a spinneret and solidified in a coagulation bath to form hollow fiber membrane filaments; 3) Hydrophilic modification: First, the hollow fiber membrane fibers are soaked in a hydrophilic modification solution for 1-5 minutes. The hydrophilic modification solution is an aqueous solution of acrylic acid with a neutralization degree of 50-70 wt%, specifically composed of: 20-40 wt% acrylic acid, 1-4 wt% sodium hydroxide, 0.02-1 wt% potassium persulfate, 0.1-0.5 wt% N,N-methylenebisacrylamide, 1-5 wt% Tween 60 and 1-2 wt% Tween 61. Then, the membrane is placed in a microwave radiation chamber for 40-80 seconds for microwave crosslinking reaction, and then placed in a hot air chamber at 50-80℃ to dry and remove surface moisture, thus obtaining a hydrophilic antifouling polyethersulfone hollow fiber membrane.

2. The method for preparing a hydrophilic antifouling polyethersulfone hollow fiber membrane as described in claim 1, characterized in that... In step 1): the polyethersulfone has a weight-average molecular weight of 50,000-70,000 and is in powder form; the dissolution temperature is 60-62℃, the concentration of polyethersulfone is 16-18wt%, the concentration of N,N-dimethylacetamide is 54-57wt%, the concentration of polyethylene glycol 400 is 8-10wt%, the concentration of polyvinylpyrrolidone is 4-6wt%, the concentration of Tween 60 is 1-2wt%, the concentration of N,N-methylenebisacrylamide is 0.5-1.2wt%, and the temperature of the casting solution is reduced to 28-30℃.

3. The method for preparing a hydrophilic antifouling polyethersulfone hollow fiber membrane as described in claim 1, characterized in that... In step 2): the casting solution and core solution are extruded through a spinneret to form a hollow fiber membrane preform. After passing through an air section of 10-30cm, it enters a coagulation bath to induce phase separation and solidify to form hollow fiber membrane filaments. Then, it enters a water bath at 5-15℃ for circulating cleaning to remove residual pore-forming agents and solvents and is then dried on the surface.

4. The method for preparing a hydrophilic antifouling polyethersulfone hollow fiber membrane as described in claim 1, characterized in that... In step 3), the specific composition of the acrylic acid aqueous solution is: 25-30 wt% acrylic acid, 2-3 wt% sodium hydroxide, 1-0.5 wt% potassium persulfate, 0.2-0.3 wt% N,N-methylenebisacrylamide, 2-4 wt% Tween 60 and 1.2-1.5 wt% Tween 61.

5. The method for preparing a hydrophilic antifouling polyethersulfone hollow fiber membrane as described in claim 1, characterized in that... In step 3): Circulating immersion is used to ensure that the surface and interior of the hollow fiber membrane are covered with the hydrophilic modification solution.

6. The method for preparing a hydrophilic antifouling polyethersulfone hollow fiber membrane as described in claim 1, characterized in that... In step 3): the power of the microwave radiation box is 2000-3000MHz, the microwave time is 50-60 seconds, and the temperature of the hot air box is 60-70℃.

7. The method for preparing a hydrophilic antifouling polyethersulfone hollow fiber membrane as described in claim 3, characterized in that... The core liquid is a mixture of N,N-dimethylacetamide and water, with water accounting for 10-30 wt%; the coagulation bath is a mixture of water and N,N-dimethylacetamide, with N,N-dimethylacetamide accounting for 0-50 wt%.

8. A hydrophilic antifouling polyethersulfone hollow fiber membrane prepared by the method according to any one of claims 1-7.

9. The application of a hydrophilic antifouling polyethersulfone hollow fiber membrane prepared by the method according to any one of claims 1-7 in household water purification, seawater desalination, and industrial wastewater treatment.

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