A continuous feeding method of polyether ether ketone and a continuous feeding device thereof

Abstract

The present application relates to the preparation field of polyether ether ketone, and discloses a continuous feeding method and device for polyether ether ketone, which comprises the following steps: S1, preheating and mixing alkali metal salt and a first solvent in a first premixing kettle, wherein the kettle temperature condition of the first premixing kettle is set to 110-165 DEG C, and a first preheated liquid mixture composition is obtained; S2, preheating and mixing hydroquinone, fluoroketone and a second solvent in a second premixing kettle, wherein the kettle temperature condition of the second premixing kettle is set to 110-165 DEG C, and a second preheated liquid mixture composition is obtained; S3, continuously feeding the first preheated liquid mixture composition and the second preheated liquid mixture composition into a polymerization kettle respectively, and under the condition of stepped temperature rising, the first preheated liquid mixture composition and the second preheated mixture are subjected to high-efficiency polymerization reaction; the applicant finds that the feeding method can not only obviously improve the synthesis efficiency, but also ensure the performance and batch stability of the polyether ether ketone product through a single polymerization kettle.

Description

Technical Field

[0001] This invention relates to the field of polyether ether ketone (PEEK), and specifically to a continuous feeding method and apparatus for PEEK. Background Technology

[0002] The current mainstream synthetic route for polyetheretherketone (PEEK) is basically derived from the nucleophilic substitution condensation reaction developed by Vigers in the 1970s. This route is widely used by various manufacturers. The main synthetic route involves melting diphenyl sulfone at high temperature, then adding 4,4'-difluorobenzophenone, hydroquinone, and sodium / potassium carbonate to a reactor and carrying out a polymerization reaction under inert gas protection to obtain poly(aryletheretherketone). In the synthesis of PEEK, diphenyl sulfone is used as a solvent; hydroquinone and sodium / potassium carbonate first react to form disodium / potassium hydroquinone, which then undergoes an aromatic nucleophilic substitution reaction with 4,4'-difluorobenzophenone. The reactants are purified to obtain PEEK. However, this preparation route still suffers from significant batch instability and low production efficiency in large-scale industrial applications.

[0003] Patent application CN 116874769 A discloses a continuous polymerization method for polyetheretherketone (PEEK). This method employs a two-reactor series continuous polymerization process. 4,4'-difluorobenzophenone, a diphenyl sulfone solution of sodium carbonate and potassium carbonate, and a diphenyl sulfone solution of hydroquinone are continuously added to a primary reactor at a constant rate in a certain proportion. After the materials react in the primary reactor, they continuously enter the secondary reactor at a constant rate from the primary reactor's outlet. After the materials react in the secondary reactor, they are continuously discharged from the secondary reactor's outlet at a constant rate, achieving continuous production of PEEK, improving production efficiency, and contributing to uniform and stable product quality. During raw material pretreatment, 4,4'-difluorobenzophenone is... The process involves melting benzophenone (-difluorobenzophenone) as reactant one in a molten tank for later use. A certain amount of diphenyl sulfone is melted and combined with sodium carbonate and potassium carbonate to form reactant two, which is then added to the molten diphenyl sulfone in a specific ratio and stirred until homogeneous. A certain amount of diphenyl sulfone is also melted and hydroquinone is added to the molten diphenyl sulfone in a specific ratio and stirred until homogeneous. In other words, this scheme involves melting the three reactants of polyetheretherketone (PEEK) separately to achieve continuous feeding into a primary reactor, followed by polymerization via two reactors. While this achieves continuous polymerization of PEEK, the essence of the scheme is still feeding the three reactants separately into the reactors. The polymerization efficiency and product yield achieved in the reactors remain mediocre. Furthermore, the two-stage reactor setup not only results in a longer actual reaction time but also, because the continuous reaction process in the two-stage reactors is dynamic, it cannot be guaranteed that there will be no residual material in the primary reactor (thus, 100% completion of the primary reaction cannot be guaranteed). This leads to changes in the proportion of reactants in the reactors, resulting in significant batch-to-batch stability variations. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a continuous feeding method and a continuous feeding device for polyether ether ketone. The applicant has found that this feeding method not only significantly improves the synthesis efficiency, but also ensures the performance and batch stability of polyether ether ketone products through a single polymerization reactor.

[0005] The technical solution adopted in this invention is as follows: A continuous feeding method for polyetheretherketone (PEEK) includes the following steps: S1. The alkali metal salt and the first solvent are preheated and mixed in a first premixing vessel, the temperature of the first premixing vessel is set to 110-165℃, to obtain a first preheated liquid mixture composition; the alkali metal salt is sodium carbonate and / or potassium carbonate, and the first solvent is diphenyl sulfone; the mass ratio of the alkali metal salt to the first solvent is in the range of 1:0.5-2. S2. Hydroquinone, fluoroketone, and the second solvent are preheated and mixed in a second premixing vessel. The temperature of the second premixing vessel is set to 110-165℃ to obtain a second preheated liquid mixture composition. The second solvent is diphenyl sulfone. The mass ratio of the fluoroketone, hydroquinone, and the second solvent is in the range of 1:1-1.5:1-2. S3. The first preheated liquid mixture and the second preheated liquid mixture are continuously fed into the polymerization reactor. Under the step-heating condition, the first preheated liquid mixture and the second preheated mixture undergo a high-efficiency polymerization reaction in the polymerization reactor. After the reaction is completed, the polyether ether ketone reaction solution is directly obtained from the discharge end of the polymerization reactor.

[0006] Preferably, in step S1, the mass ratio of the alkali metal salt to the first solvent is in the range of 1:0.8-1.6.

[0007] Preferably, in step S1, after introducing an inert gas to replace the air in the first premixing vessel and simultaneously controlling the temperature of the first premixing vessel to the target temperature, the first solvent is delivered to the first premixing vessel through a feed pump, and then the alkali metal salt is added to the first premixing vessel and stirred thoroughly to obtain the first preheated liquid mixture composition.

[0008] Preferably, in step S2, the fluoroketone is 4,4'-difluorobenzophenone.

[0009] Preferably, in step S2, after the air in the second premixing vessel is replaced by an inert gas and the temperature of the second premixing vessel is simultaneously controlled to the target temperature, the second solvent is delivered to the second premixing vessel through a feed pump. Then, hydroquinone and fluoroketone are added to the second premixing vessel and stirred thoroughly to obtain the second preheated liquid mixture composition.

[0010] Preferably, the temperature conditions of the first premixing vessel in step S1 are the same as those of the second premixing vessel in step S2, and the temperature conditions of the first premixing vessel in step S1 are set to 135-160℃.

[0011] Preferably, in step S3, an inert gas is introduced to replace the air in the polymerization reactor, and the reactor temperature is simultaneously controlled to 110-160°C. Then, the first preheated liquid mixture composition and the second preheated liquid mixture composition are successively added into the polymerization reactor, and the temperature in the polymerization reactor is raised stepwise from the specified temperature to 280-350°C. The reaction time in the polymerization reactor is 2.5-3.5 hours.

[0012] Preferably, the polyetheretherketone reaction solution is discharged into a tablet press through a closed pipeline to obtain crude polyetheretherketone; the crude polyetheretherketone is pressed into thin sheets, and the thin sheets are crushed, washed and dried to obtain polyetheretherketone product; wherein the yield of the polyetheretherketone product is not less than 92%.

[0013] Preferably, a continuous feeding device for polyetheretherketone (PEEK) includes a first premixing vessel, a second premixing vessel, and a polymerization vessel; wherein, The first premixing vessel is respectively provided with a solid phase feeding inlet for adding alkali metal salts, a first solvent injection port, and a first preheated liquid mixture discharge port; the first solvent injection port is connected to a first solvent feed pump, and a first solvent flow meter is provided on the connecting pipeline; The second premixing vessel is provided with one or more solid phase feeding inlets, a second solvent injection port, and a second preheated liquid mixture discharge port; the second solvent injection port is connected to a second solvent feed pump, and a second solvent flow meter is provided on the connecting pipeline; The polymerization reactor is connected to the discharge port of the first preheated liquid mixture and the discharge port of the second preheated liquid mixture, respectively.

[0014] Preferably, the reaction product outlet of the polymerization reactor is connected to a tablet press via a sealed pipeline.

[0015] This application proposes a mixing scheme consisting of a first premixing vessel and a second premixing vessel. The key aspect is that: an alkali metal salt and a first solvent are preheated and mixed in the first premixing vessel to obtain a first preheated liquid mixture composition; simultaneously, hydroquinone, fluoroketone, and a second solvent are preheated and mixed in the second premixing vessel to obtain a specific second preheated liquid mixture composition (hydroquinone and fluoroketone are preheated and mixed in a specific combination under a solvent atmosphere); then, the first preheated liquid mixture composition and the specific second preheated liquid mixture composition are continuously fed into a polymerization vessel. Under stepped heating conditions, the first preheated liquid mixture composition and the second preheated mixture composition achieve a stable and efficient polymerization reaction in the polymerization vessel. After the reaction, a high-yield and batch-stable polyetheretherketone reaction solution is directly obtained from the outlet of the polymerization vessel. The applicant found that this feeding method not only significantly improves the synthesis efficiency but also ensures the performance and batch stability of the polyetheretherketone product through a single polymerization vessel. Attached Figure Description

[0016] Figure 1 This is a flowchart of the continuous feeding method for polyetheretherketone (PEEK) according to a specific embodiment of this application; Figure 2 This is a structural connection diagram of the continuous feeding device for polyetheretherketone (PEEK) according to a specific embodiment of this application. Detailed Implementation

[0017] Please refer to the above. Figure 1 and Figure 2 As shown in the figure, this embodiment proposes a continuous feeding method for polyetheretherketone (PEEK), which includes the following operation steps: S1. The alkali metal salt and the first solvent are preheated and mixed in the first premixing vessel. The temperature of the first premixing vessel is set to 110-165℃ to obtain the first preheated liquid mixture composition. S2. The hydroquinone, fluoroketone and the second solvent are preheated and mixed in the second premixing vessel. The temperature of the second premixing vessel is set to 110-165℃ to obtain the second preheated liquid mixture composition. S3. The first preheated liquid mixture and the second preheated liquid mixture are continuously fed into the polymerization reactor. Under the condition of step heating, the first preheated liquid mixture and the second preheated mixture undergo a high-efficiency polymerization reaction in the polymerization reactor. After the reaction is completed, the polyether ether ketone reaction liquid is directly obtained from the discharge end of the polymerization reactor. Preferably, in this embodiment, the polyether ether ketone reaction liquid is discharged to the tablet press through a closed pipeline to obtain crude polyether ether ketone. The crude polyether ether ketone is pressed into thin sheets, and the thin sheets are crushed, washed and dried to obtain the polyether ether ketone product. The yield of the polyether ether ketone product is not less than 92%.

[0018] Preferably, in step S1, the alkali metal salt is sodium carbonate and / or potassium carbonate, and the first solvent is diphenyl sulfone.

[0019] Preferably, in step S1, the mass ratio of the alkali metal salt to the first solvent is in the range of 1:0.5-2, more preferably 1:0.8-1.6.

[0020] Preferably, in step S1, after the air in the first premixing vessel is replaced by an inert gas and the temperature of the first premixing vessel is controlled to the target temperature, the first solvent is delivered to the first premixing vessel through a feed pump, and then the alkali metal salt is added to the first premixing vessel and stirred thoroughly to obtain the first preheated liquid mixture composition.

[0021] Preferably, in step S2, the fluoroketone is 4,4'-difluorobenzophenone; and the second solvent is diphenyl sulfone.

[0022] Preferably, in step S2, the mass ratio of fluoroketone, hydroquinone, and the second solvent is in the range of 1:1-1.5:1-2.

[0023] Preferably, in step S2, an inert gas is introduced to replace the air in the second premixing vessel, and the temperature of the second premixing vessel is simultaneously controlled to the target temperature. Then, the second solvent is delivered to the second premixing vessel through a feed pump, and hydroquinone and fluoroketone are added to the second premixing vessel respectively and stirred thoroughly to obtain the second preheated liquid mixture composition.

[0024] Preferably, the temperature conditions of the first premixing vessel in step S1 are the same as those of the second premixing vessel in step S2, and the temperature conditions of the first premixing vessel in step S1 are set to 135-160℃.

[0025] Preferably, in step S3, an inert gas is introduced to replace the air in the polymerization reactor, and the reactor temperature is simultaneously controlled to 110-160°C. Then, the first preheated liquid mixture composition and the second preheated liquid mixture composition are successively added into the polymerization reactor, and the temperature inside the polymerization reactor is raised stepwise from the specified temperature to 280-350°C.

[0026] Preferably, a continuous feeding device for polyetheretherketone (PEEK) includes a first premixing vessel, a second premixing vessel, and a polymerization vessel; wherein, The first premixing vessel is respectively provided with a solid feeding inlet for adding alkali metal salts, a first solvent injection port, and a first preheated liquid mixture discharge port; the first solvent injection port is connected to a first solvent feed pump, and a first solvent flow meter is provided on the connecting pipeline; The second premixing vessel is provided with one or more solid phase feeding inlets, a second solvent injection port, and a second preheated liquid mixture discharge port; the second solvent injection port is connected to the second solvent feed pump, and a second solvent flow meter is provided on the connecting pipeline; The polymerization reactor is connected to the discharge ports of the first preheated liquid mixture and the second preheated liquid mixture, respectively; preferably, the discharge port of the reaction product of the polymerization reactor is connected to the tablet press through a closed pipeline.

[0027] To enable those skilled in the art to better understand the technical solutions of this invention, based on the above embodiments, the following specific embodiments will be proposed in conjunction with the accompanying drawings. Obviously, the described embodiments are merely some embodiments of this invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort should fall within the scope of protection of this invention.

[0028] It should be noted that the raw materials involved in the following embodiments of this application are all directly purchased from the market.

[0029] Example 1: High-purity nitrogen is introduced to replace the air in the first premixing vessel, and the temperature of the premixing vessel is simultaneously controlled to the specified temperature: 145℃. Then, diphenyl sulfone is fed into the first premixing vessel by a feed pump and a flow meter to replace the air in the first premixing vessel. Then, sodium carbonate is added into the first premixing vessel by a weighing device and stirred thoroughly. After that, high-purity nitrogen is purged again. High-purity nitrogen is introduced to replace the air in the second premixing vessel, and the temperature of the premixing vessel is simultaneously controlled to the specified temperature range: 145℃. Then, diphenyl sulfone is fed into the second premixing vessel by a feed pump and a flow meter at a specified weight. High-purity nitrogen is introduced to replace the air in the second premixing vessel. Then, hydroquinone and 4,4'-difluorobenzophenone are successively added to the second premixing vessel by a weighing device and thoroughly stirred. After the mixture is purged with high-purity nitrogen again, the mixture is purged with high-purity nitrogen. High-purity nitrogen gas is introduced to replace the air in the polymerization reactor, and the reactor temperature is simultaneously controlled to a specified temperature of 145℃. Then, the materials from the first premixing reactor and the second premixing reactor are successively added into the polymerization reactor, and the temperature is slowly increased in a stepwise manner (the specific heating conditions are: first, the temperature is increased to 245℃ at a rate of 5℃ / min, and then increased to 330℃ at a rate of 10℃ / min) until the reaction ends at 330℃ (the reaction time is 2.5 hours). The progress of the reactants in the polymerization reactor is monitored online. Fluoroketone is added as a capping agent, and the reaction is stopped after half an hour. The discharge valve of the polymerization reactor is opened, and the material is discharged into the tablet press through a closed pipeline to obtain crude PEEK resin (i.e., polyether ether ketone). The crude PEEK resin is pressed into thin sheets, and the sheets are crushed, washed, and dried to obtain the polyether ether ketone product. In this Example 1, the total feed ratio was set as follows: diphenyl sulfone: sodium carbonate: hydroquinone: fluoroketone = 3:1:1.1:1, and the amount of fluoroketone fed was 2 mol; the reaction time in the polymerization reactor was 3 hours.

[0030] To verify the batch stability of the embodiments of this application, five consecutive batches of the above steps were performed in this embodiment 1. After testing, the yield of the obtained polyether ether ketone product was greater than 92%. Specifically, the yields of the five batches of polyether ether ketone product were 93.5%, 94.1%, 93.3%, 93.7%, and 94.8%, respectively.

[0031] This application also conducted strength performance tests on the five batches of polyetheretherketone products obtained in this embodiment, specifically, the performance of the five batches of polyetheretherketone products are as follows: The first batch has a tensile strength of 101.37 MPa and a flexural modulus of 4.01 GPa. The second batch: its tensile strength is 100.94 MPa and its flexural modulus is 3.98 GPa; The third batch: its tensile strength is 101.49 MPa and its flexural modulus is 4.02 GPa; The fourth batch: its tensile strength is 101.15 MPa, and its flexural modulus is 3.99 GPa; The fifth batch has a tensile strength of 100.78 MPa and a flexural modulus of 3.98 GPa.

[0032] The tensile strength described in this application is based on ASTM D638-2024, and the flexural modulus is based on ASTM D790-2024.

[0033] Example 2: High-purity nitrogen is introduced to replace the air in the first premixing vessel, and the temperature of the premixing vessel is simultaneously controlled to the specified temperature: 130℃. Then, diphenyl sulfone is fed into the first premixing vessel by a feed pump and a flow meter, and high-purity nitrogen is introduced to replace the air in the first premixing vessel. Then, sodium carbonate is added to the first premixing vessel by a weighing device and stirred thoroughly before being replaced with high-purity nitrogen again. High-purity nitrogen is introduced to replace the air in the second premixing vessel, and the temperature of the premixing vessel is simultaneously controlled to the specified temperature range: 130℃. Then, diphenyl sulfone is fed into the second premixing vessel by a feed pump and a flow meter at a specified weight. High-purity nitrogen is introduced to replace the air in the second premixing vessel. Then, hydroquinone and 4,4'-difluorobenzophenone are successively added to the second premixing vessel by a weighing device and thoroughly stirred. After being replaced by high-purity nitrogen again, the mixture is stirred. High-purity nitrogen gas is introduced to replace the air in the polymerization reactor, and the reactor temperature is simultaneously controlled to the specified temperature: 160℃. Then, the materials from the first premixing reactor and the second premixing reactor are successively added into the polymerization reactor, and the temperature is slowly increased in a stepwise manner (the specific temperature increase conditions are: first increase the temperature to 245℃ at a rate of 5℃ / min, and then increase the temperature to 310℃ at a rate of 10℃ / min) until the reaction ends (the reaction time is 2.25 hours). The progress of the reactants in the polymerization reactor is monitored online. Fluoroketone is added as a capping agent, and the reaction ends after 15 minutes. The discharge valve of the polymerization reactor is opened, and the material is discharged into the tablet press through a closed pipeline to obtain crude PEEK resin (i.e., polyether ether ketone). The crude PEEK resin is pressed into thin sheets, and the sheets are crushed, washed, and dried to obtain the polyether ether ketone product.

[0034] The overall feed ratio was set as follows: diphenyl sulfone: sodium carbonate: hydroquinone: fluoroketone = 3.6:1:1.05:1, and the amount of fluoroketone fed was 2 mol; the reaction time in the polymerization reactor was 2.5 hours.

[0035] To verify the batch stability of the embodiments of this application, this embodiment 2 was carried out for three consecutive batches following the above steps. After testing, the yield of the obtained polyether ether ketone product was greater than 92%. Specifically, the yields of the polyether ether ketone products in the three batches were 92.9%, 93.5%, and 93.1%, respectively.

[0036] Example 3: High-purity nitrogen gas is introduced to replace the air in the first premixing vessel, and the temperature of the premixing vessel is simultaneously controlled to the specified temperature: 155℃. Then, diphenyl sulfone is fed into the first premixing vessel by a feed pump and a flow meter, and high-purity nitrogen gas is introduced to replace the air in the first premixing vessel. Then, potassium carbonate is added to the first premixing vessel by a weighing device and stirred thoroughly. After that, high-purity nitrogen gas is purged again. High-purity nitrogen is introduced to replace the air in the second premixing vessel, and the temperature of the premixing vessel is simultaneously controlled to the specified temperature range: 155℃. Then, diphenyl sulfone is fed into the second premixing vessel by a feed pump and a flow meter at a specified weight. High-purity nitrogen is introduced to replace the air in the second premixing vessel. Then, hydroquinone and 4,4'-difluorobenzophenone are successively added to the second premixing vessel by a weighing device and thoroughly stirred. After that, high-purity nitrogen is introduced to replace the air in the second premixing vessel again. High-purity nitrogen gas is introduced to replace the air in the polymerization reactor, and the reactor temperature is simultaneously controlled to a specified temperature of 150℃. Then, the materials from the first premixing reactor and the second premixing reactor are successively added into the polymerization reactor, and the temperature is slowly increased in a stepwise manner (the specific heating conditions are: first, the temperature is increased to 245℃ at a rate of 5℃ / min, and then increased to 300℃ at a rate of 10℃ / min) until the reaction ends at 300℃ (the reaction time is 3 hours). The progress of the reactants in the polymerization reactor is monitored online. Fluoroketone is added as a capping agent. The reaction is stopped after half an hour. The discharge valve of the polymerization reactor is opened, and the material is discharged into the tablet press through a closed pipeline to obtain crude PEEK resin (i.e., polyether ether ketone). The crude PEEK resin is pressed into thin sheets, and the sheets are crushed, washed, and dried to obtain the polyether ether ketone product.

[0037] The overall feed ratio was set as follows: diphenyl sulfone: potassium carbonate: hydroquinone: fluoroketone = 3.5:1:1.4:1, and the amount of fluoroketone fed was 2 mol; the reaction time in the polymerization reactor was 3.5 hours.

[0038] To verify the batch stability of the embodiments of this application, this embodiment 3 was carried out with three consecutive batches of the above steps. After testing, the yield of the obtained polyether ether ketone product was greater than 92%. Specifically, the yields of the polyether ether ketone products of the three batches were 94.3%, 94.2%, and 93.8%, respectively.

[0039] Comparative Example 1: The remaining technical solutions of Comparative Example 1 are the same as those of Example 1, except that the first premixing kettle and the second mixing kettle are eliminated in Comparative Example 1, and the raw materials are directly and continuously fed into the polymerization kettle respectively; the product yields obtained in the three consecutive batches are low and vary greatly, namely 80.9%, 76.3%, and 70.1% respectively; the batch stability is significantly worse than that of Example 1.

[0040] Comparative Example 2: The remaining technical solutions of Comparative Example 2 are the same as those of Example 1, except that in Comparative Example 2, the first premixing vessel is eliminated and the raw materials of the first premixing vessel are directly and continuously fed into the polymerization vessel; the product yields of the three consecutive batches are low and vary greatly, namely 82.9%, 88.6%, and 86.4%; the batch stability is significantly worse than that of Example 1.

[0041] Comparative Example 3: The remaining technical solutions of Comparative Example 3 are the same as those of Example 1, except that in Comparative Example 3, the second premixing vessel is eliminated and the raw materials of the second premixing vessel are directly and continuously fed into the polymerization vessel. The product yields of the three consecutive batches are low and vary greatly, at 91.4%, 86.9%, and 85.1%, respectively. The batch stability is significantly worse than that of Example 1.

[0042] Comparative Example 4: The remaining technical solutions of Comparative Example 4 are the same as those of Example 1, except that in Comparative Example 4, the second premixing vessel is eliminated, and the raw materials of the first premixing vessel are sent to the second premixing vessel for premixing together with the raw materials of the second premixing vessel; the product yields obtained in three consecutive batches are low and vary greatly, namely 88.3%, 92.4%, and 83.9% respectively; the batch stability is significantly worse than that of Example 1.

[0043] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0044] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A continuous feeding method for polyetheretherketone (PEEK), characterized in that, The following steps are included: S1. An alkali metal salt and a first solvent are preheated and mixed in a first premixing vessel. The temperature of the first premixing vessel is set to 135-160℃ to obtain a first preheated liquid mixture composition. The alkali metal salt is sodium carbonate and / or potassium carbonate, and the first solvent is diphenyl sulfone. The mass ratio of the alkali metal salt to the first solvent is in the range of 1:0.5-2. S2. Hydroquinone, fluoroketone, and the second solvent are preheated and mixed in a second premixing vessel. The temperature of the second premixing vessel is set to 135-160℃ to obtain a second preheated liquid mixture composition. The second solvent is diphenyl sulfone. The mass ratio of the fluoroketone, hydroquinone, and the second solvent is in the range of 1:1-1.5:1-2. S3. The first preheated liquid mixture and the second preheated liquid mixture are continuously fed into the polymerization reactor. Under the step-heating condition, the first preheated liquid mixture and the second preheated mixture undergo a high-efficiency polymerization reaction in the polymerization reactor. After the reaction is completed, the polyether ether ketone reaction solution is directly obtained from the discharge end of the polymerization reactor.

2. The continuous feeding method for polyetheretherketone according to claim 1, characterized in that, In step S1, the mass ratio of the alkali metal salt to the first solvent is in the range of 1:0.8-1.

6.

3. The continuous feeding method for polyetheretherketone according to claim 1 or 2, characterized in that, In step S1, an inert gas is introduced to replace the air in the first premixing vessel. After the temperature of the first premixing vessel is controlled to the target temperature, the first solvent is delivered to the first premixing vessel through a feed pump. Then, the alkali metal salt is added to the first premixing vessel and stirred thoroughly to obtain the first preheated liquid mixture composition.

4. The continuous feeding method for polyetheretherketone according to claim 1, characterized in that, In step S2, the fluoroketone is 4,4'-difluorobenzophenone.

5. The continuous feeding method for polyetheretherketone according to claim 1 or 4, characterized in that, In step S2, an inert gas is introduced to replace the air in the second premixing vessel. After the temperature of the second premixing vessel is controlled to the target temperature, the second solvent is delivered to the second premixing vessel through a feed pump. Then, hydroquinone and fluoroketone are added to the second premixing vessel and stirred thoroughly to obtain the second preheated liquid mixture composition.

6. The continuous feeding method for polyetheretherketone according to claim 1, characterized in that, The temperature conditions of the first premixing vessel in step S1 are set to the same state as the temperature conditions of the second premixing vessel in step S2.

7. The continuous feeding method for polyetheretherketone according to claim 1, characterized in that, In step S3, an inert gas is introduced to replace the air in the polymerization reactor, and the reactor temperature is simultaneously controlled to 145-160°C. Then, the first preheated liquid mixture composition and the second preheated liquid mixture composition are successively added into the polymerization reactor, and the temperature inside the polymerization reactor is raised stepwise from the specified temperature to 280-350°C. The reaction time in the polymerization reactor is 2.5-3.5 hours.

8. The continuous feeding method for polyetheretherketone according to claim 1, characterized in that, The polyetheretherketone (PEEK) reaction solution is discharged into a tablet press through a closed pipeline to obtain crude PEEK. The crude PEEK is pressed into thin sheets, which are then crushed, washed, and dried to obtain the PEEK product. The yield of the PEEK product is not less than 92%.

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