Efficient and rapid synthesis method of high-molecular-weight polyether sulfone

Abstract

The invention discloses an efficient and rapid synthesis method of high molecular weight polyether sulfone, which comprises the following steps: (a) in a nitrogen or argon atmosphere, sequentially adding an aromatic diphenol monomer, an alkali metal salt, a mixed organic solvent and water into a reaction kettle, then stirring and heating to 100-120 DEG C, dissolving the aromatic diphenol monomer and salifying; (b) after the salt forming reaction is performed for 10 to 30 minutes, adjusting the temperature of the reaction kettle to 120 to 150 DEG C, and removing water from a reaction system; (c) removing water for 0.5-2 hours, adding an aromatic dihalogenated compound monomer into the system, raising the reaction temperature to 160-250 DEG C, reacting for 1-7 hours, and carrying out polymerization reaction to obtain reaction feed liquid; and (d) precipitating, cleaning and drying the reaction material liquid to obtain the polyethersulfone resin. The synthesis method has the advantages of simplicity in operation, short time, high efficiency, low energy consumption and the like, and the obtained product is high in molecular weight and high in quality.

Description

Technical Field

[0001] This invention relates to the field of polymer material synthesis technology, and in particular to an efficient and rapid synthesis method for high molecular weight polyether sulfone. Background Technology

[0002] Polyethersulfone (PES) is a traditional engineering plastic with excellent thermal stability, chemical stability, high mechanical strength and oxidation resistance, and easy processing and molding. It is widely used in membrane separation, medical, machinery manufacturing, and electronics industries. The principle and process of synthesizing PES includes the following three key steps: (1) activation of aromatic diphenol monomers to form salts; (2) removal of water, a small molecule byproduct generated during the salt formation process; and (3) co-condensation reaction of aromatic diphenol salts and aromatic dihalogen monomers to generate PES. In the above reaction process, the activation of aromatic diphenol monomers to form salts is slow and inefficient, which becomes the key step that determines the efficiency and time of PES synthesis.

[0003] The core reason for the slow activation and salt formation of aromatic bisphenol monomers is that this salt formation reaction mainly uses strongly alkaline metal salts (such as potassium bicarbonate, potassium carbonate, sodium hydroxide, potassium hydroxide, etc.) as catalysts in a high-boiling-point and highly stable sulfolane solvent. During the activation of bisphenol S to bisphenol S potassium (sodium) salt (4',4-dipotassium (sodium)oxydiphenyl sulfone), bisphenol S monopotassium (sodium) salt (4-hydroxy-4-potassium (sodium)oxydiphenyl sulfone) precipitates out of the solvent. Moreover, the alkali metal catalyst is poorly soluble in sulfolane, which makes it difficult for the bisphenol S monopotassium (sodium) salt solid and the alkali metal catalyst solid to be further activated and salted (slow solid-solid medium reaction, low efficiency). The required activation time is long (greater than 12 hours) and the required activation temperature is high (greater than 140 ℃), resulting in a waste of time and energy. The monomer activation is incomplete, making it difficult to accurately control the monomer feed ratio and polymerization reaction. The resulting polyethersulfone has a low molecular weight and high cost.

[0004] Furthermore, due to the high conjugation degree and high synthesis temperature of polyethersulfone (PES), the use of strongly alkaline alkali metal catalysts in the actual synthesis process can accelerate the decomposition rate of sulfolane, causing the reaction solution to turn black. This results in a lower molecular weight of the synthesized PES, a longer synthesis cycle, and difficulty in controlling product quality. Conversely, using weakly alkaline alkali metal salts as catalysts, such as sodium bicarbonate or sodium carbonate, to activate bisphenol S into its potassium (sodium) salt form causes the precipitation of monopotassium (sodium) bisphenol S in the reaction system, leading to slow monomer activation, requiring high activation temperatures (above 230 °C), resulting in high energy consumption and a dangerous experimental process.

[0005] Therefore, the polyethersulfone synthesis process mentioned above has certain defects, and the polyethersulfone synthesized using the above synthesis process has a low molecular weight, high cost, and low quality, which seriously limits the practical application of polyethersulfone. Summary of the Invention

[0006] The purpose of this invention is to provide an efficient and rapid synthesis method for high molecular weight polyethersulfone, in order to solve the problems of high activation temperature, high energy consumption and dangerous experiments in the above-mentioned polyethersulfone synthesis process, and the low molecular weight and low quality of the obtained product.

[0007] To achieve the above objectives, the first aspect of the present invention provides an efficient and rapid synthesis method for high molecular weight polyether sulfone, comprising the following steps: (a) Under a nitrogen or argon atmosphere, add aromatic diphenol monomer, alkali metal salt, mixed organic solvent and water in sequence to a reaction vessel, then stir and heat to 100~120 °C to dissolve the aromatic diphenol monomer and form a salt; (b) After the salt formation reaction has been going on for 10 to 30 minutes, the temperature of the reactor is adjusted to 120 to 150 °C and the reaction system is dehydrated. (c) After removing water for 0.5 to 2 h, add aromatic dihalogenated compound monomers to the system, raise the reaction temperature to 160 to 250 °C and react for 1 to 7 h to carry out the polymerization reaction and obtain the reaction solution; (d) After the reaction solution is subjected to precipitation, washing and drying, polyethersulfone resin is obtained.

[0008] Preferably, in step (a), the general structural formula of the aromatic diphenol monomer is as follows: ; Component R1 is any derivative containing a sulfone group.

[0009] Preferably, in step (a), the alkali metal salt is one or more of potassium carbonate, sodium carbonate, sodium hydroxide, potassium hydroxide, sodium hydride, and potassium hydride.

[0010] Preferably, in step (a), the mixed organic solvent includes a high-boiling-point organic solvent with a boiling point above 180 °C and a low-boiling-point organic solvent with a boiling point below 150 °C. The high-boiling-point organic solvent is sulfolane, and the low-boiling-point organic solvent is one or more of benzene, toluene, xylene, chlorobenzene, ethylbenzene, pyridine, and cyclohexane.

[0011] Preferably, in step (a), the volume ratio of the high-boiling-point organic solvent, the low-boiling-point organic solvent, and water is 1:(0.2~1):(0.12~0.4).

[0012] Preferably, in step (c), the general structural formula of the aromatic dihalogenated compound monomer is as follows: ; Among them, components R2 and R4 are halogen atoms, and component R3 is composed of any compound or element.

[0013] Preferably, the molar ratio of aromatic diphenol monomer, aromatic dihalogenated compound monomer and alkali metal salt is 1:(0.8~1.2):(1~6); wherein the required mixed organic solvent per molar amount of aromatic diphenol monomer is 0.2~3 L.

[0014] The second aspect of this invention provides the application of high molecular weight polyethersulfone prepared by the above-mentioned efficient and rapid synthesis method in the fields of biology, medicine, pharmaceuticals, semiconductors, coatings, environmental protection, and membrane separation.

[0015] Preferably, the polyethersulfone prepared by the above synthesis method has a number-average molecular weight greater than 60,000 Da and a weight-average molecular weight greater than 100,000 Da.

[0016] Therefore, the present invention employs the above-mentioned efficient and rapid synthesis method for high molecular weight polyethersulfone, which has the following beneficial effects: (1) The present invention adopts a novel synthesis process, which shortens the synthesis time and saves energy. The prepared polyethersulfone material can be applied to fields such as biology, medicine, machinery manufacturing, aviation, automobile, petrochemical, electronic information, and membrane separation.

[0017] (2) The polyethersulfone resin prepared by the synthesis method of the present invention has a short production cycle, and the resulting material has a high molecular weight and stable performance, making it suitable for industrial scale-up.

[0018] The technical solution of the present invention will be further described in detail below through embodiments. Detailed Implementation

[0019] The present invention will be further described below. It should be noted that this embodiment is based on the present technical solution and provides detailed implementation methods and specific operation processes, but the present invention is not limited to this embodiment.

[0020] Example 1 A highly efficient and rapid synthesis method for high molecular weight polyether sulfone includes the following steps: 0.1 mol of bisphenol S and 0.2 mol of KOH were added to a four-necked flask. The system was subjected to a Schlenk operation to ensure an inert gas atmosphere. 150 mL of sulfolane, 50 mL of water, and 140 mL of toluene were added to the system. The temperature was adjusted to 138 °C for 30 min of activation. After activation, the water in the four-necked flask was removed. After dehydration, the xylene in the system was drained. 0.1 mol of p-chlorodiphenyl sulfone was added to the system. The temperature was adjusted to 208 °C and the reaction was allowed to proceed for 7.5 h. The reaction solution was then filtered through a 5 μm PTFE filter membrane. The filtered reaction solution was then settled in pure water to obtain solid particles. A certain amount of hydrochloric acid was added, and the mixture was repeatedly washed until the pH was neutral. Finally, the obtained solid material was thoroughly dried in a 60 °C oven to obtain the desired material.

[0021] Comparative Example 1 A method for synthesizing a polyethersulfone material includes the following steps: 0.1 mol of bisphenol S and 0.2 mol of KOH were added to a four-necked flask. The system was subjected to a Schlenk operation to ensure an inert gas atmosphere. 150 mL of sulfolane and 140 mL of toluene were added, and the system temperature was adjusted to 138 °C for 24 h of activation. After activation, the toluene was removed, and 0.1 mol of p-chlorodiphenyl sulfone was added. The system temperature was adjusted to 208 °C, and the reaction was allowed to proceed for 7.5 h. The reaction solution was then filtered through a 5 μm PTFE filter membrane. The filtered reaction solution was then settled in pure water to obtain solid particles. A certain amount of hydrochloric acid was added, and the mixture was repeatedly washed until the pH was neutral. Finally, the obtained solid material was thoroughly dried in a 60 °C oven to obtain the desired material.

[0022] Test case The dried polyethersulfone was tested using a DVS digital rotational viscometer (DVS+, Brookfield Ametek). A rotor of size 31 was used, with the rotor completely submerged in the test solution. The rotational speed was set to 10 rpm, and the torque range was controlled between 10% and 100%. Specific test results are shown in Table 1.

[0023]

[0024] The molecular weights of the synthesized polyethersulfone (PES) were compared with those of commercially available PES, which were purchased directly. The comparison results are shown in Table 2.

[0025] In Example 1, different volumes of water were added during the activation of bisphenol S to bisphenol S potassium salt. The dehydration time and the viscosity of the synthesized polymer were compared, with the activation time fixed at 30 min. The comparison results are shown in Table 3.

[0026]

[0027] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A highly efficient and rapid synthesis method for high molecular weight polyethersulfone, characterized in that: Includes the following steps: (a) Under a nitrogen or argon atmosphere, aromatic diphenol monomer, alkali metal salt, mixed organic solvent, and water are added sequentially to a reaction vessel, then stirred and heated to 100-120 °C to dissolve the aromatic diphenol monomer and form a salt; the mixed organic solvent includes high-boiling-point organic solvents with boiling points above 180 °C and low-boiling-point organic solvents with boiling points below 150 °C; the volume ratio of high-boiling-point organic solvent, low-boiling-point organic solvent, and water is 1:(0.2-1):(0.12-0.4). (b) After the salt formation reaction has been going on for 10 to 30 minutes, the temperature of the reactor is adjusted to 120 to 150 °C and the reaction system is dehydrated. (c) After removing water for 0.5 to 2 h, add aromatic dihalogenated compound monomers to the system, raise the reaction temperature to 160 to 250 °C and react for 1 to 7 h to carry out the polymerization reaction and obtain the reaction solution; (d) After the reaction solution is subjected to precipitation, washing and drying, polyethersulfone resin is obtained.

2. The efficient and rapid synthesis method for high molecular weight polyethersulfone according to claim 1, characterized in that: In step (a), the general structural formula of the aromatic diphenol monomer is shown below: ； Component R1 is any derivative containing a sulfone group.

3. The efficient and rapid synthesis method for high molecular weight polyethersulfone according to claim 1, characterized in that: In step (a), the alkali metal salt is one or more of potassium carbonate, sodium carbonate, sodium hydroxide, potassium hydroxide, sodium hydride, and potassium hydride.

4. The efficient and rapid synthesis method for high molecular weight polyethersulfone according to claim 1, characterized in that: In step (a), the high-boiling-point organic solvent is sulfolane, and the low-boiling-point organic solvent is one or more of benzene, toluene, xylene, chlorobenzene, ethylbenzene, pyridine, and cyclohexane.

5. The efficient and rapid synthesis method for high molecular weight polyethersulfone according to claim 1, characterized in that: In step (c), the general structural formula of the aromatic dihalogenated compound monomer is shown below: ； Among them, components R2 and R4 are halogen atoms, and component R3 is composed of any compound or element.

6. The efficient and rapid synthesis method for high molecular weight polyethersulfone according to claim 1, characterized in that: The molar ratio of aromatic diphenol monomer, aromatic dihalogenated compound monomer and alkali metal salt is 1:(0.8~1.2):(1~6); wherein the required mixed organic solvent per molar amount of aromatic diphenol monomer is 0.2~3 L.

7. The application of high molecular weight polyethersulfone prepared by the efficient and rapid synthesis method according to any one of claims 1 to 6 in the fields of biology, medicine, pharmaceuticals, semiconductors, coatings, environmental protection, and membrane separation.

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