A polyethersulfone, a method of preparation and use thereof

Abstract

This invention discloses a polyethersulfone, its preparation method, and its applications. The polyethersulfone satisfies the following formula: x = A1 / (A1+A2) < 6%; where A1 is the integral area occupied by the weight-average molecular weight of not less than 200,000 g / mol in the GPC spectrum, and A1 is denoted as the high molecular weight peak area; A2 is the integral area occupied by the weight-average molecular weight of less than 200,000 g / mol in the GPC spectrum, and A2 is denoted as the main peak area. The polyethersulfone prepared by this invention exhibits a bimodal molecular weight distribution, with the main peak area accounting for more than 90%. The main peak molecular weight can be controlled, and the weight-average molecular weight is between 60,000 and 180,000 g / mol, which can meet the performance requirements of applications such as hemodialysis membranes.

Description

Technical Field

[0001] This invention belongs to the field of polymer material synthesis, specifically relating to a polyethersulfone, its preparation method, and its application. Background Technology

[0002] Polyethersulfone (PES) is a high-performance special engineering plastic, belonging to the sulfone polymer family. Its main chain contains aryl, sulfone, and ether bonds. PES possesses excellent thermal stability, water vapor resistance, flame retardancy and self-extinguishing properties, creep resistance, dimensional stability, mechanical properties, and biocompatibility. It is widely used in electronics, automotive, aerospace, kitchenware, and medical devices. With the increasing demand for high-performance materials as society develops, the application range of PES is becoming increasingly broad.

[0003] Currently, conventional sulfone polymers are prepared by polycondensation reaction of dihydroxy aromatic monomers (bisphenol A, biphenyl, bisphenol S, etc.) and dichloro aromatic monomers (dichlorodiphenyl sulfone) in the presence of a salting agent. However, compared with bisphenol A and biphenyl, the monomer bisphenol S of polyethersulfone is more acidic and forms phenolate with the salting agent at a faster rate. This results in the prepared polyethersulfone products affecting the viscosity of the spinning solution, pore-forming properties, and dialysis effect when used in hemodialysis membranes.

[0004] CN115028837A discloses an aromatic sulfone polymer, wherein the peak area S of the polymer chain with a molecular weight greater than 150,000 g / mol is... M150000 Peak area S of total polymer chains M The proportion is between 7-10%. This aromatic sulfone polymer can be used to prepare molded plastic parts, ultrafiltration membranes, coatings, etc., but when applied to hemodialysis membranes, the above-mentioned defects still exist, making it difficult to meet application requirements.

[0005] Therefore, it is necessary to develop polyethersulfone products that meet the performance requirements for applications such as hemodialysis membranes. Summary of the Invention

[0006] The inventors of this application, by optimizing the molecular weight distribution of polyethersulfone and reducing the proportion of the high molecular weight portion (weight-average molecular weight > 200,000 g / mol) in polyethersulfone to a specific range, unexpectedly discovered that the prepared polyethersulfone product could meet the application performance requirements of hemodialysis membranes, thus completing this invention.

[0007] To achieve the above objectives, one objective of the present invention is to provide a polyethersulfone product with a high molecular weight fraction (weight average molecular weight not less than 200,000 g / mol) of less than 6%, which can meet the application requirements of hemodialysis membranes.

[0008] Another object of the present invention is to provide a method for preparing such polyethersulfone.

[0009] Another object of the present invention is to provide applications for such polyethersulfone products.

[0010] To achieve the above-mentioned objectives, the present invention adopts the following technical solution:

[0011] A polyethersulfone, the general structural formula of which is shown in formula (I):

[0012]

[0013] Wherein, the following formula is satisfied: x = A1 / (A1+A2) < 6%, preferably, x = A1 / (A1+A2) < 5%, more preferably, x = A1 / (A1+A2) < 3%;

[0014] Where A1 is the integral area occupied by the weight-average molecular weight of not less than 200,000 g / mol in the GPC spectrum, and A1 is denoted as the high molecular weight peak area; A2 is the integral area occupied by the weight-average molecular weight of less than 200,000 g / mol in the GPC spectrum, and A2 is denoted as the main peak area.

[0015] In one specific implementation, the weight-average molecular weight of the main peak is between 60,000 and 180,000 g / mol, preferably between 80,000 and 145,000 g / mol.

[0016] In one specific implementation, the molecular weight distribution is less than 2.0, preferably 1.2 to 1.8.

[0017] On the other hand, the aforementioned method for preparing polyethersulfone includes the following steps:

[0018] 1) Salt formation stage: Dissolve monomer one and monomer two in the reaction solvent, then add salt forming agent and dehydrating agent to the reaction vessel under stirring, heat and reflux reaction, and then raise the temperature to completely evaporate the dehydrating agent in the reaction vessel; wherein, at least one of monomer one, monomer two and salt forming agent is added in batches;

[0019] 2) Polymerization stage: After the polymerization reaction, the stirring speed is reduced, and then a capping agent is added for capping. Subsequently, the reaction mixture is filtered, crushed, washed with water, and vacuum dried to obtain polyethersulfone.

[0020] In one specific implementation, the monomer and / or salt-forming agent are added in batches.

[0021] In a preferred embodiment, the monomer and / or salt-forming agent are added in three batches; preferably, they are added in three batches at the beginning of the reaction, after reflux for 1 hour, and after reflux for 3 hours.

[0022] In a specific implementation plan, the phased addition can be either proportional or non-proportional.

[0023] In one specific implementation, the salt formation stage is heated to 140–220°C and refluxed for 2–6 hours, while the polymerization stage is carried out at 160–230°C for 2–48 hours.

[0024] In one specific implementation, monomer one is bisphenol S, and monomer two is one or more of dichlorodiphenyl sulfone and difluorodiphenyl sulfone.

[0025] In one specific embodiment, the salt-forming agent is one or more of sodium hydroxide, potassium hydroxide, cesium hydroxide, potassium carbonate, sodium carbonate, cesium carbonate, potassium bicarbonate, and sodium bicarbonate.

[0026] In one specific embodiment, the reaction solvent is any one of dimethyl sulfoxide, dimethyl sulfone, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, and sulfolane.

[0027] In one specific implementation, the water-removing agent is one or more of toluene, xylene, o-xylene, chlorobenzene, and mesitylene.

[0028] In one specific implementation, the capping agent is chloromethane.

[0029] In one specific implementation, the blade tip linear velocity of the agitator during the salt formation stage is between 6 and 10 m / s, and the blade tip linear velocity of the agitator during the polymerization stage is between 2 and 4 m / s.

[0030] On the other hand, the polyethersulfone mentioned above or the polyethersulfone prepared by the aforementioned method is used in the fields of electronics, automotive and aerospace, kitchenware and medical devices, with a preference for its use in hemodialysis membranes.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] (1) The polyethersulfone product of the present invention has a narrow molecular weight distribution, and the area of ​​high molecular weight peaks with a weight average molecular weight of not less than 200,000 g / mol in the GPC spectrum is less than 6%, which can meet the performance requirements of application scenarios such as hemodialysis membranes.

[0033] (2) The preparation method of the present invention efficiently solves the key problems in the polymerization of polyethersulfone. The molecular weight of the main peak of polyethersulfone can be controlled to a weight-average molecular weight between 60,000 and 180,000 g / mol, which has certain guiding significance for the industrial production of sulfone series products. Attached Figure Description

[0034] Figure 1 The image shows the GPC spectrum of the polyethersulfone prepared in Example 1 of this invention. Detailed Implementation

[0035] Preferred embodiments of the invention will now be described in more detail. While preferred embodiments of the invention are described below, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein.

[0036] A polyethersulfone, the general structural formula of which is shown in formula (I):

[0037]

[0038] The following formula must be satisfied: x = A1 / (A1+A2) < 6%, for example, x < 5%, x < 4%, x < 3%, x < 2%, x < 1%, etc., preferably x = A1 / (A1+A2) < 5%, more preferably x = A1 / (A1+A2) < 3%;

[0039] Where A1 is the integral area occupied by the weight-average molecular weight of not less than 200,000 g / mol in the GPC spectrum, and A1 is denoted as the high molecular weight peak area; A2 is the integral area occupied by the weight-average molecular weight of less than 200,000 g / mol in the GPC spectrum, and A2 is denoted as the main peak area.

[0040] The GPC testing conditions in this invention are as follows: N,N-dimethylformamide is used as the mobile phase, the flow rate is 1.0 mL / min, polystyrene is used as the reference standard, and Shodex KD-802, KD-803 and KD-804 columns are used in series.

[0041] The polyethersulfone of the present invention has a main peak weight-average molecular weight between 60,000 and 180,000 g / mol, for example, weight-average molecular weights of 60,000 g / mol, 70,000 g / mol, 80,000 g / mol, 90,000 g / mol, 100,000 g / mol, 110,000 g / mol, 120,000 g / mol, 130,000 g / mol, 140,000 g / mol, 150,000 g / mol, 160,000 g / mol, 170,000 g / mol, 180,000 g / mol, etc., preferably between 80,000 and 145,000 g / mol. Simultaneously, the molecular weight distribution is less than 2.0, for example, 1.9, 1.8, 1.7, 1.6, 1.5, 1.4, 1.3, 1.2, etc., preferably between 1.2 and 1.8. Given the above-mentioned weight-average molecular weight and molecular weight distribution, the degree of polymerization n of polyethersulfone in formula (I) can also be determined accordingly, for example, n is 100 to 800, preferably 300 to 600.

[0042] The polyethersulfone with the above-mentioned structural characteristics has a very small proportion of high molecular weight portion with a weight average molecular weight of not less than 200,000 g / mol, for example, less than 6%, preferably less than 5%, more preferably less than 3%, and has the characteristic of narrow molecular weight distribution. Therefore, when the prepared polyethersulfone product is used in hemodialysis membrane, it will have a relatively small impact on the viscosity and pore-forming properties of the spinning solution, and ultimately will not affect the dialysis effect.

[0043] Those skilled in the art will understand that any polyethersulfone possessing the above-mentioned structural characteristics can exhibit essentially the same performance when applied to hemodialysis membranes, regardless of the method used to prepare the polyethersulfone product with these structural characteristics.

[0044] Polyethersulfone (PES) is typically prepared by a nucleophilic substitution reaction of bisphenol S salts (sodium, potassium, etc.) with dichlorodiphenyl sulfone, followed by chloromethane end-capping. To prepare PES products with the aforementioned performance characteristics, the inventors of this application discovered that one reason for the wide molecular weight distribution and high content of the high molecular weight fraction in PES is the rapid salt formation rate of bisphenol S with the salting agent. This rapid and short-term release of large amounts of gas easily causes material splashing, resulting in material adhering to the walls, leading to monomer imbalance and increased dead zones. This, in turn, widens the molecular weight distribution of PES. Therefore, it is necessary to control the salt formation rate to reduce material splashing.

[0045] In addition, another important reason why the molecular weight distribution of polyethersulfone is multi-peaked is that as the viscosity of the system increases, the mass and heat transfer in the system is insufficient and untimely, and there are hot spots. Therefore, it is necessary to strengthen the stirring intensity, optimize the material circulation in the system, control the stirring intensity at a high level, and further optimize the material distribution in the system.

[0046] The following provides an exemplary preparation method, but does not constitute any limitation. A method for preparing polyethersulfone includes the following steps:

[0047] All or part of the monomer and salt-forming agent are added to the reaction solvent, and then a dehydrating agent is added to the reaction vessel under stirring. The mixture is heated to 140-220℃ and refluxed for 2-6 hours, with the blade tip linear velocity of the agitator between 6-10 m / s. The temperature is increased to completely evaporate the dehydrating agent in the reaction vessel, and then the mixture is reacted at 160-230℃ for 2-48 hours, with the blade tip linear velocity of the agitator between 2-4 m / s. After that, a certain amount of end-capping agent is added, and then the reaction vessel is hydraulically filtered, crushed, washed with water, and vacuum dried to obtain polyethersulfone.

[0048] Wherein, monomer one is bisphenol S, monomer two is one or more of dichlorodiphenyl sulfone and difluorodiphenyl sulfone, preferably dichlorodiphenyl sulfone; the salting agent is one or more of sodium hydroxide, potassium hydroxide, cesium hydroxide, potassium carbonate, sodium carbonate, cesium carbonate, potassium bicarbonate, and sodium bicarbonate, preferably sodium carbonate and / or potassium carbonate; the reaction solvent is one of dimethyl sulfoxide, dimethyl sulfone, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, and sulfolane, preferably N-methylpyrrolidone or sulfolane; the dehydrating agent is one or more of toluene, xylene, o-xylene, chlorobenzene, and mesitylene, preferably xylene; and the end-capping agent is chloromethane.

[0049] During the salt formation stage, the mixture is heated to 140–220°C and refluxed for 2–6 hours. The reflux temperature can be, for example, 140°C, 150°C, 160°C, 170°C, 180°C, 190°C, 200°C, 210°C, 220°C, etc. The specific temperature can be set according to the boiling point of the reaction solvent, for example, below the boiling point of the reaction solvent. The reflux time can be, for example, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, etc., depending on whether water is produced.

[0050] During the polymerization stage, the reaction is carried out at 160–230℃ for 2–48 hours. For example, the polymerization reaction temperature is 160℃, 170℃, 180℃, 190℃, 200℃, 210℃, 220℃, etc., and the polymerization reaction time is 2h, 3h, 4h, 5h, 6h, 10h, 15h, 20h, 25h, 30h, 35h, 40h, 45h, 48h, etc. In the actual preparation process, the degree of polymerization reaction can also be judged by monitoring indicators such as the viscosity or current value of the reaction system.

[0051] In this invention, there are no particular restrictions on the amount of each reactant. For example, taking bisphenol S and dichlorodiphenyl sulfone as reactants, the molar ratio of bisphenol S to dichlorodiphenyl sulfone is 1:1.0 to 1:1.03. The amount of salt-forming agent added is 1.05 to 1.3 times the molar amount of bisphenol S. The amount of reaction solvent added is to make the solid content of the reaction system reach 20% to 40%. The amount of dehydrating agent added is 0.1 to 0.5 times the mass of the reaction solvent. The amount of capping agent added is 0.02 to 0.1 times the molar amount of bisphenol S.

[0052] In this invention, all or part of bisphenol S, dichlorodiphenyl sulfone, and / or the salt-forming agent are added to the reaction solvent. For example, bisphenol S, dichlorodiphenyl sulfone, or the salt-forming agent are added in batches, or they are added in pairs in batches, or all three are added simultaneously in batches. The batch addition can be, for example, in three or more equal or unequal portions added multiple times. Preferably, the salt-forming agent is added in batches at the beginning of the reaction, at 1 hour of reflux, and at 3 hours of reflux, but it is not limited to this. For example, it can be added in batches at the beginning of the reaction, at 2 hours of reflux, and at 4 hours of reflux, or at the beginning of the reaction, at 1.5 hours of reflux, and at 3.5 hours of reflux. To improve the reaction efficiency and shorten the reaction time, it is preferable to add all the salt-forming agent in batches within 5 hours of the reaction.

[0053] In a preferred embodiment, the stirring intensity during the salt formation and polymerization stages is further controlled. For example, the blade tip linear velocity of the agitator during the salt formation stage is controlled between 6 and 10 m / s, such as 6 m / s, 7 m / s, 8 m / s, 9 m / s, and 10 m / s; the blade tip linear velocity during the polymerization stage is controlled between 2 and 4 m / s, such as 2 m / s, 2.5 m / s, 3 m / s, 3.5 m / s, and 4 m / s. By controlling the blade tip linear velocity of the agitator during the salt formation and polymerization stages, the material circulation within the system is optimized, further optimizing the material distribution within the system and resulting in a narrower molecular weight distribution.

[0054] All reaction conditions described in this invention are under a nitrogen atmosphere. The reaction vessels used are baked, dried, and dehydrated, and then repeatedly evacuated and purged with nitrogen. Steps not specifically described in this invention can be referenced from existing technologies. For example, processes such as hydraulic filtration, crushing, washing, and vacuum drying can all be achieved using conventional techniques in this field.

[0055] The present invention will be further explained and illustrated below through more specific embodiments, but these do not constitute any limitation.

[0056] The test methods and test conditions used in the following embodiments are as follows:

[0057] Molecular structure was characterized using GPC with N,N-dimethylformamide as the mobile phase at a flow rate of 1.0 mL / min, polystyrene as the reference standard, and Shodex KD-802, KD-803, and KD-804 columns used in series.

[0058] Example 1

[0059] 2002g of bisphenol S, 2320g of dichlorodiphenyl sulfone, and 424g of potassium carbonate were added sequentially to 6894g of sulfolane. Then, 1380g of xylene was added to the reactor. During the salt formation stage, the blade tip linear velocity of the agitator was 6m / s. The mixture was heated to 180℃ and refluxed with water. After refluxing for 1h and 3h, 423g of potassium carbonate was added respectively. When no more water was produced, the temperature was increased to completely evaporate the xylene in the reactor. The blade tip linear velocity of the agitator was adjusted to 2m / s. The reaction was then carried out at 220℃ for 3.5h. After cooling to 150℃, chloromethane was introduced for 30min. Finally, the reaction mixture was filtered, crushed, washed with water, and vacuum dried to obtain polyethersulfone.

[0060] Molecular structure characterization: GPC spectra as follows Figure 1 As shown, the weight-average molecular weight of the main peak of the prepared polyethersulfone is 137200 g / mol, the molecular weight distribution is 1.94, and x = 3.4%.

[0061] Example 2

[0062] The difference from Example 1 is that N-methylpyrrolidone was used as the solvent, the polymerization temperature was 190°C, and the polymerization time was 6 hours.

[0063] Molecular structure characterization: The weight-average molecular weight of polyethersulfone is 139350 g / mol, the molecular weight distribution is 1.88, and x = 4.8%.

[0064] Example 3

[0065] The difference from Example 1 is that sodium carbonate is used as the salt-forming agent, and sodium carbonate is added in three equal parts, with 340g, 339g, and 339g of sodium carbonate added at the initial stage, after 1 hour of reflux, and after 3 hours of reflux, respectively.

[0066] Molecular structure characterization: The weight-average molecular weight of the polyethersulfone main peak is 142,200 g / mol, the molecular weight distribution is 1.82, and x = 4.3%.

[0067] Example 4

[0068] The difference from Example 1 is that a mixture of potassium carbonate (663g) and sodium carbonate (509g) was used as a salting agent, and 221g of potassium carbonate / 170g of sodium carbonate, 221g of potassium carbonate / 169g of sodium carbonate, and 221g of potassium carbonate / 169g of sodium carbonate were added at the beginning of the reaction, 1 hour of reflux, and 3 hours of reflux, respectively.

[0069] Molecular structure characterization: The weight-average molecular weight of the polyethersulfone main peak is 140020 g / mol, the molecular weight distribution is 1.78, and x = 2.9%.

[0070] Example 5

[0071] The difference from Example 1 is that a process of adding bisphenol S in three equal parts was adopted, with 668g, 667g, and 667g of bisphenol S added at the beginning of the reaction, 1h of reflux, and 3h of reflux, respectively.

[0072] Molecular structure characterization: The weight-average molecular weight of polyethersulfone is 139,000 g / mol, the molecular weight distribution is 1.65, and x = 3.1%.

[0073] Example 6

[0074] The difference from Example 1 is that a process of adding potassium carbonate and bisphenol S in three unequal portions is adopted, with 635g potassium carbonate / 1001g bisphenol S, 318g potassium carbonate / 501g bisphenol S, and 317g potassium carbonate / 500g bisphenol S added at the beginning of the reaction, 1h of reflux, and 3h of reflux, respectively.

[0075] Molecular structure characterization: The weight-average molecular weight of polyethersulfone is 141,300 g / mol, and the molecular weight distribution is 1.72, x = 2.6%.

[0076] Example 7

[0077] The difference from Example 6 is that the blade tip linear velocity of the agitator during the salt formation stage is 10 m / s.

[0078] Molecular structure characterization: The weight-average molecular weight of polyethersulfone is 140240 g / mol, the molecular weight distribution is 1.72, and x = 1.1%.

[0079] Example 8

[0080] The difference from Example 1 is that the polymerization time is extended to 6 hours.

[0081] Molecular structure characterization: The weight-average molecular weight of polyethersulfone is 179010 g / mol, the molecular weight distribution is 1.92, and x = 5.2%.

[0082] Example 9

[0083] The difference from Example 1 is that the blade tip linear velocity of the agitator is 6 m / s throughout the reaction stage.

[0084] Molecular structure characterization: The weight-average molecular weight of polyethersulfone is 140230 g / mol, the molecular weight distribution is 1.84, and x = 5.7%.

[0085] Comparative Example 1

[0086] The difference from Example 1 is that all materials were added at the beginning of the reaction, and the blade tip linear velocity of the agitator was 2 m / s throughout the reaction.

[0087] Molecular structure characterization: The weight-average molecular weight of the polyethersulfone main peak is 138,400 g / mol, the molecular weight distribution is 2.11, and the area of ​​the main peak accounts for x = 22.8%.

[0088] Comparative Example 2

[0089] The difference from Example 1 is that all materials were added at the beginning of the reaction, while all other conditions were exactly the same.

[0090] Molecular structure characterization: The weight-average molecular weight of the polyethersulfone main peak is 139760 g / mol, the molecular weight distribution is 2.05, and x = 13.3%.

[0091] In the polyethersulfone products prepared in the embodiments of the present invention, the area of ​​high molecular weight peaks with a weight-average molecular weight greater than or equal to 200,000 g / mol accounts for less than 6%, and the weight-average molecular weight of the main polyethersulfone peak is between 60,000 and 180,000 g / mol. According to feedback from downstream customers, polyethersulfone products with this structural feature can meet the application performance requirements of hemodialysis membranes.

Claims

1. A polyethersulfone that can be used in hemodialysis membranes, having the general structural formula shown in formula (I): Equation (I) Its features are, Satisfy the following formula: x=A1 / (A1+A2)<6%, the weight-average molecular weight of the main peak is between 60000 and 180000 g / mol, and the molecular weight distribution is less than 2.0; Where A1 is the integral area occupied by the weight-average molecular weight of not less than 200,000 g / mol in the GPC spectrum, and A1 is denoted as the high molecular weight peak area; A2 is the integral area occupied by the weight-average molecular weight of less than 200,000 g / mol in the GPC spectrum, and A2 is denoted as the main peak area; The preparation method of the polyethersulfone includes the following steps: 1) Salt formation stage: Dissolve monomer one and monomer two in the reaction solvent, then add salt-forming agent and dehydrating agent to the reaction vessel under stirring, heat to reflux reaction, and then raise the temperature to completely evaporate the dehydrating agent in the reaction vessel; wherein, at least one of monomer one, monomer two, and salt-forming agent is added in batches; monomer one is bisphenol S, and monomer two is one or more of dichlorodiphenyl sulfone and difluorodiphenyl sulfone; 2) Polymerization stage: After the polymerization reaction, the stirring speed is reduced, and then a capping agent is added for capping. Subsequently, the reaction mixture is filtered, crushed, washed with water, and vacuum dried to obtain polyethersulfone. The blade tip linear velocity of the agitator during the salt formation stage is between 6 and 10 m / s, while the blade tip linear velocity during the polymerization stage is between 2 and 4 m / s.

2. The polyethersulfone according to claim 1, characterized in that, x = A1 / (A1 + A2) < 5%.

3. The polyethersulfone according to claim 2, characterized in that, x = A1 / (A1 + A2) < 3%.

4. The polyethersulfone according to any one of claims 1 to 3, characterized in that, The weight-average molecular weight of the main peak is between 80,000 and 145,000 g / mol.

5. The polyethersulfone according to claim 4, characterized in that, Molecular weight distribution: 1.2–1.

8.

6. The polyethersulfone according to claim 1, characterized in that, The monomer and / or salt-forming agent are added in batches.

7. The polyethersulfone according to claim 6, characterized in that, The monomer and / or salt-forming agent are added in three batches.

8. The polyethersulfone according to claim 7, characterized in that, The monomer and / or salt-forming agent are added in three batches at the beginning of the reaction, after reflux for 1 hour, and after reflux for 3 hours.

9. The polyethersulfone according to claim 6, characterized in that, The phased addition can be either proportional or non-proportional.

10. The polyethersulfone according to claim 1, characterized in that, During the salt formation stage, the mixture is heated to 140-220℃ and refluxed for 2-6 hours. During the polymerization stage, the mixture is reacted at 160-230℃ for 2-48 hours.

11. The polyethersulfone according to claim 1, characterized in that, The salt-forming agent is one or more of sodium hydroxide, potassium hydroxide, cesium hydroxide, potassium carbonate, sodium carbonate, cesium carbonate, potassium bicarbonate, and sodium bicarbonate.

12. The polyethersulfone according to claim 1, characterized in that, The reaction solvent is any one of dimethyl sulfoxide, dimethyl sulfone, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, and sulfolane.

13. The polyethersulfone according to claim 1, characterized in that, The water-removing agent is one or more of toluene, xylene, chlorobenzene, and mesitylene.

14. The polyethersulfone according to claim 1, characterized in that, The capping agent is chloromethane.

15. The application of the polyethersulfone according to any one of claims 1 to 14 in the fields of electronics and electrical appliances, automotive and aerospace, kitchenware, and medical devices.

16. The application according to claim 15, characterized in that, Application in hemodialysis membranes.

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