Process for the preparation of polyetherketoneketones and polyetherketoneketones prepared thereby

Abstract

The application discloses a method for preparing polyether ketone ketone and polyether ketone ketone prepared by the method, and the method comprises the following steps: (1) adding a first part of raw materials and diphenyl ether and a solvent into a reaction container, wherein the first part of raw materials comprises part of a Lewis acid and part of a Lewis base; (2) adding a first acyl chloride solution at a first dropping speed; (3) after temperature rising, adding a second part of raw materials and adding a second acyl chloride solution at a second dropping speed, wherein the second part of raw materials comprises the remaining Lewis acid and Lewis base, the molar ratio of the Lewis acid and the Lewis base in the first part of raw materials to the Lewis acid and the Lewis base in the second part of raw materials is (5-9):(5-1), the mass ratio of acyl chloride in the first acyl chloride solution to acyl chloride in the second acyl chloride solution is (5-9):(5-1), and the first and second dropping speeds are 2.2%vol / min-6.6%vol / min. The polyether ketone ketone prepared by the method has a narrow molecular weight distribution.

Description

Technical Field

[0001] This application relates to the field of polymers, specifically to a method for preparing polyether ketone ketones and the polyether ketone ketones prepared therefrom. Background Technology

[0002] Polyetherketoneketone (PEKK) is widely used in aerospace, automotive manufacturing, and electronics industries due to its advantages such as high temperature resistance, good self-lubrication, chemical resistance, radiation resistance, and good mechanical properties. In the 1960s, DuPont reported a method for preparing PEKK using aluminum trichloride as a catalyst and diphenyl ether and terephthaloyl chloride as monomers in a nitrobenzene solution. However, this method involved numerous side reactions, resulting in low intrinsic viscosity of the synthesized PEKK, making it impractical for application. Subsequently, foreign companies gradually developed two routes for PEKK polymerization research. One was the Lewis acid-Lewis base co-catalysis method invented by Raychem, which synthesizes gel-like crude PEKK in a chlorinated solvent / Lewis acid / Lewis base catalytic system. This method can produce high molecular weight polymers, but it suffers from numerous side reactions and poor batch stability, making it difficult to apply to industrial production. The other route was DuPont's two-step method, which first prepares a trimer from diphenyl ether and terephthaloyl chloride, and then uses the purified trimer as a monomer to synthesize the PEKK product. DuPont's two-step method largely solved the problem of numerous side reactions in PEKK and was successfully put into industrial production. However, this method has high production costs and is difficult to promote in the market, thus it has not been widely used. Currently, the electrophilic substitution method for preparing PEKK basically follows or modifies Raychem's Lewis acid-Lewis base co-catalysis method. This method uses dichloromethane as a solvent, adds diphenyl ether, acyl chloride, and Lewis acid at low temperature, and then raises the temperature. Under the co-catalysis of Lewis base and Lewis acid, PEKK can be prepared at room temperature. This method adds Lewis base and Lewis acid to the polymerization system to form a complex system with aluminum trichloride in solution. Its advantage is that this complex system has enough active end groups to allow the polymer chain to continue to grow.

[0003] In electrophilic substitution, controlling the monomer concentration distribution in the reactant system and suppressing side reactions have a significant impact on the molecular weight distribution, thermal stability, and processing performance of the product. Improving the homogeneity of the reactants can enhance the structural homogeneity of the product. However, how to precisely control the various parameters in the reaction process and optimize and balance the reaction efficiency and product quality has become one of the important research directions for optimizing the PEKK synthesis process and improving the overall performance of the material. Summary of the Invention

[0004] In view of the above problems, this application provides a method for preparing polyether ketone ketone and the polyether ketone ketone prepared therefrom. This method, by adding Lewis acid, Lewis base, and acyl chloride in two batches and precisely controlling the ratio between the key raw materials and solvents, as well as the dropping rate of the acyl chloride, can achieve the preparation of narrow molecular weight polyether ketone ketone within a short preparation cycle, thus achieving a better balance between reaction efficiency and product quality.

[0005] In one aspect of this application, a method for preparing polyetherketoneketone is proposed. The method includes: (1) mixing a first part of raw materials, diphenyl ether, and solvent at a first temperature and adding them to a reaction vessel, wherein the first part of raw materials includes a portion of Lewis acid and a portion of Lewis base; (2) adding a first acyl chloride solution to the reaction vessel at a first drop rate and maintaining the first temperature; (3) heating to a second temperature, adding a second part of raw materials, and adding a second acyl chloride solution at a second drop rate, wherein the second part of raw materials includes the remaining Lewis acid and the remaining Lewis base, wherein the second temperature is higher than the first temperature, the molar ratio of Lewis acid in the first part of raw materials to Lewis acid in the second part of raw materials is (5-9):(5-1), the molar ratio of Lewis base in the first part of raw materials to Lewis base in the second part of raw materials is (5-9):(5-1), the mass ratio of acyl chloride in the first acyl chloride solution to the mass ratio of acyl chloride in the second acyl chloride solution is (5-9):(5-1), the first drop rate is 2.2%vol / min to 6.6%vol / min, and the second drop rate is 2.2%vol / min to 6.6%vol / min.

[0006] This method, by precisely controlling the ratio between key raw materials and solvents as well as the dropping rate of acyl chloride, can produce polyether ketone ketone with a narrow molecular weight distribution within a short production cycle. The acyl chloride solution is added dropwise in two stages, which can significantly shorten the time required for adding raw materials. Therefore, it has the advantages of producing high-quality polyether ketone ketone and high production efficiency.

[0007] According to an embodiment of the present invention, both the first acyl chloride solution and the second acyl chloride solution include the solvent, and the ratio of the total mass of the solvent to the total mass of the solute acyl chloride in the first and second acyl chloride solutions is 4:1 to 15:1, optionally 10:1, wherein the total mass of the solvent is the sum of the mass of the solvent added in step (1), the mass of the solvent contained in the first acyl chloride solution, and the mass of the solvent contained in the second acyl chloride solution. This further improves the quality of the obtained polyetherketoneketone.

[0008] According to an embodiment of the present invention, M 路易斯碱总摩尔 M 酰氯总摩尔The ratio is from 1.5:1 to 3.0:1, optionally 2.5:1, wherein M 路易斯碱总摩尔 M represents the total molar number of Lewis bases in the first and second portions of the raw materials added; 酰氯总摩尔 This refers to the total number of moles of acyl chloride in the first and second acyl chloride solutions added. This can further improve the quality of the obtained polyetherketone ketone.

[0009] According to an embodiment of the present invention, M 路易斯酸总摩尔 :(M 酰氯总摩尔 +M 路易斯碱总摩尔 The ratio is 1.2:1 to 2.0:1, optionally 1.5:1, where M 路易斯酸总摩尔 M represents the total number of moles of Lewis acids in the first and second portions of the raw materials added. 酰氯总摩尔 M represents the total number of moles of acyl chloride in the first and second acyl chloride solutions added. 路易斯碱总摩尔 This refers to the total molar number of Lewis bases in the first and second portions of the raw materials added. This can further improve the quality of the obtained polyetherketone ketone.

[0010] According to an embodiment of the present invention, the ratio of the molar number of the added diphenyl ether to the total molar number of the acyl chloride is 0.8:1 to 1.2:1, optionally 1:1, wherein the total molar number of the acyl chloride is the total number of molar numbers of the acyl chloride in the first acyl chloride solution and the second acyl chloride solution. This further improves the quality of the obtained polyetherketoneketone.

[0011] According to an embodiment of the present invention, the mass ratio of the solvent to the acyl chloride in the first and second acyl chloride solutions is 1:1 to 3:1, optionally 1.5:1. This further improves the quality of the obtained polyetherketoneketone.

[0012] According to an embodiment of the present invention, the method satisfies at least one of the following requirements: the mass ratio of Lewis acid in the first portion of the raw material to Lewis acid in the second portion of the raw material is (6-8):(4-2); the molar ratio of Lewis base in the first portion of the raw material to Lewis base in the second portion of the raw material is (6-8):(4-2); and the molar ratio of acyl chloride in the first acyl chloride solution to the molar ratio of acyl chloride in the second acyl chloride solution is (6-8):(4-2). This further improves the quality of the obtained polyetherketoneketone.

[0013] According to an embodiment of the present invention, the solute acyl chlorides in the first and second acyl chloride solutions are independently selected from one, two, or three of terephthaloyl chloride, phthaloyl chloride, and isophthaloyl chloride; the Lewis base is selected from one, two, or more of N,N-dimethylformamide, dimethylacetamide, diphenyl sulfone, triphenylphosphine oxide, nitropropane, sulfolane, dimethyl sulfoxide, dimethyl sulfone, N-methylpyrrolidone, anhydrous lithium chloride, and anhydrous sodium chloride; the Lewis acid includes one, two, or more of anhydrous aluminum trichloride, anhydrous ferric chloride, boron trifluoride, anhydrous zinc dichloride, anhydrous antimony pentachloride, and anhydrous tin dichloride; the solvent includes one, two, or more of dichloromethane, dichloroethane, o-dichlorobenzene, carbon disulfide, and nitrobenzene. Therefore, the quality of the obtained polyetherketone ketone can be further improved.

[0014] According to an embodiment of the present invention, the first acyl chloride solution includes terephthaloyl chloride, and the concentration of the terephthaloyl chloride in the first acyl chloride solution is 25% to 50%; the second acyl chloride solution includes isophthaloyl chloride, and the concentration of the isophthaloyl chloride in the second acyl chloride solution is 25% to 50%. This further improves the quality of the obtained polyetherketone ketone.

[0015] According to an embodiment of the present invention, the ratio of the total moles of acyl chloride in the first acyl chloride solution to the total moles of acyl chloride in the second acyl chloride solution is (6-8):(4-2). This further improves the quality of the obtained polyetherketone.

[0016] According to an embodiment of the present invention, before adding the first portion of raw materials, diphenyl ether, and solvent to the reaction vessel, the temperature of the reaction vessel is pre-cooled, and an inert gas is introduced, including one, two, or three of nitrogen, argon, and neon. This further improves the quality of the obtained polyetherketoneketone.

[0017] According to an embodiment of the present invention, the first temperature is -25℃ to 0℃, and the second temperature is 15℃ to 25℃; in step (2), the first temperature is maintained for 0.5 to 1.5 hours; in step (3), the reaction is carried out for 3 to 5 hours after the second acyl chloride solution is added dropwise. This further improves the quality of the obtained polyether ketone.

[0018] According to an embodiment of the present invention, step (3) is further followed by the addition of hydrochloric acid as a terminating agent, and the mixture is allowed to stand for 4 to 10 hours. This further improves the quality of the obtained polyetherketone ketone.

[0019] According to an embodiment of the present invention, the method further includes: sequentially crushing, sieving, and washing the reaction product, wherein the crushing process includes grinding and pulverizing, and the washing process includes water washing, organic solvent washing, and acid washing. This can further improve the quality of the obtained polyetherketoneketone.

[0020] In another aspect of this application, a polyetherketoneketone is provided, which is prepared using the method described above. This polyetherketoneketone has the advantages of high quality and low production cost.

[0021] According to an embodiment of the present invention, the molecular weight distribution coefficient of the polyetherketone is between 2.5 and 4.6, and the weight-average molecular weight is between 15w and 16w. Detailed Implementation

[0022] The technical solution of this application will be described in detail below with reference to the embodiments. The following embodiments are only used to illustrate the technical solution of this application more clearly, and are therefore only examples, and should not be used to limit the protection scope of this application.

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the description and claims of this application are intended to cover non-exclusive inclusion.

[0024] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0025] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0026] In the description of the embodiments of this application, the terms "multiple" or "repeatedly" refer to two or more times (including two), and similarly, "multiple groups" refer to two or more groups (including two groups).

[0027] Unless otherwise stated, the terms used in this application have their common meanings as commonly understood by those skilled in the art. Unless otherwise stated, the values ​​of the parameters mentioned in this application can be measured using various measurement methods commonly used in the art (e.g., they can be tested according to the methods given in the embodiments of this application).

[0028] In one aspect of this application, a method for preparing polyether ketone ketone is provided. The method includes:

[0029] (1) The first part of the raw materials, diphenyl ether, and solvent are mixed and added to the reaction vessel at a first temperature. The first part of the raw materials includes a portion of Lewis acid and a portion of Lewis base.

[0030] (2) The first acyl chloride solution is added to the reaction vessel at a first drop rate, while maintaining the first temperature;

[0031] (3) After heating to the second temperature, the second part of the raw materials is added, and the second acyl chloride solution is added dropwise at the second drop rate. The second part of the raw materials includes the remaining Lewis acid and the remaining Lewis base. The second temperature is higher than the first temperature.

[0032] The molar ratio of Lewis acid in the first part of the raw material to Lewis acid in the second part of the raw material is (5-9):(5-1), the molar ratio of Lewis base in the first part of the raw material to Lewis base in the second part of the raw material is (5-9):(5-1), the mass ratio of acyl chloride in the first acyl chloride solution to the mass ratio of acyl chloride in the second acyl chloride solution is (5-9):(5-1), the acceleration rate of the first drop is 2.2%vol / min to 6.6%vol / min, and the acceleration rate of the second drop is 2.2%vol / min to 6.6%vol / min.

[0033] As mentioned earlier, the preparation of PEKK using the electrophilic substitution method typically involves the addition of Lewis acids and Lewis bases. The combined action of these two substances causes the polymer to form a complex system in solution, as shown in the typical reaction equation below:

[0034]

[0035] In the Lewis acid-base co-catalytic method for preparing polyetherketoneketone (PEKK), Lewis acids (such as AlCl3 in the above formula) and Lewis bases (such as DMF in the above formula) mainly provide suitable conditions for the reaction through synergistic effects. During the synthesis of PEKK, the dropping rate of the reactants is a core parameter for controlling the monomer concentration distribution in the reaction system, suppressing side reactions, and ensuring the uniformity of the product structure. It has a direct and crucial impact on the molecular weight distribution, thermal stability, and processing performance of the final PEKK material. An excessively rapid dropping rate of reactants, especially acyl chlorides, leads to excessively high local acyl chloride concentrations in the reaction system, easily triggering side reactions such as cross-linking and chain termination, resulting in a wider molecular weight distribution of the product. Conversely, an excessively slow dropping rate prolongs the reaction cycle, not only reducing production efficiency but also potentially causing product structural inhomogeneity. Therefore, controlling the dropping rate of reactants to balance reaction efficiency and product quality has become one of the important research directions for optimizing the PEKK synthesis process and improving the overall performance of the material.

[0036] Therefore, controlling the dropping rate of raw materials, especially acyl chlorides, has a significant impact on the performance of the reaction products. Furthermore, the addition methods of Lewis acids and Lewis bases, as well as the proportion of key solvents, all affect the initial catalyst and monomer concentrations. Improper settings can lead to problems such as a sudden increase in monomer concentration causing a violent reaction and the formation of insoluble solids, or a wide rate range where the molecular weight distribution is too wide at slow rates and a sudden increase in local monomer concentration at fast rates may cause aggregation. At the same time, a lack of solvent ratio optimization can lead to uneven monomer dissolution, further increasing the risk of runaway reaction.

[0037] This invention is based on the fact that terephthaloyl chloride has higher reactivity than isophthaloyl chloride. Terephthaloyl chloride is first added at a low temperature of -20°C to effectively slow down the reaction rate of the highly reactive terephthaloyl chloride, avoiding localized concentrated growth of molecular chains due to its rapid polymerization caused by high reactivity. At the same time, with the optimized dropping rate, the monomer is uniformly dispersed in the system, achieving slow and orderly growth of molecular chains. After the terephthaloyl chloride reaction is stable, the temperature is raised to 20°C and then isophthaloyl chloride is added. The heated environment can enhance the reactivity of the low-reactivity isophthaloyl chloride, allowing it to fully participate in the polymerization reaction. There is no need for repeated cooling and heating, which greatly simplifies the temperature control process, reduces the frequency of equipment parameter switching and operation waiting time, and avoids the temperature gradient difference in the system caused by frequent temperature control due to the precise matching of activity and temperature, thus reducing the complexity of operation. In terms of improving the molecular weight distribution of the product, this invention avoids the problems of uneven molecular chain growth due to excessively slow dropping speed or agglomeration caused by excessively fast dropping speed by adjusting the molar ratio of terephthaloyl chloride to isophthaloyl chloride and the dropping rate of the acyl chloride solution. Simultaneously, it strictly limits the ratio and experimental procedures to ensure stable catalytic activity and uniform monomer concentration throughout the reaction, effectively reducing the molecular weight distribution of the finished product. Furthermore, this application involves only two temperature adjustments. By reducing temperature gradient fluctuations within the system, the molecular chain growth process is more uniform, further improving the stability of the product quality.

[0038] In this invention, the dropping rate is 2.2% vol to 6.6% vol / min, which is the percentage of the volume added per minute relative to the total volume of the acyl chloride solution to be added in that batch. For example, the dropping rate of the first acyl chloride solution is 2.2% vol / min to 6.6% vol / min, meaning that the percentage of the first acyl chloride solution added per minute is 2.2% vol to 6.6% vol, and the dropping rate of the second acyl chloride solution is 2.2% vol / min to 6.6% vol / min, meaning that the percentage of the second acyl chloride solution added per minute is 2.2% vol to 6.6% vol.

[0039] According to an embodiment of the present invention, both the first acyl chloride solution and the second acyl chloride solution include the solvent, and the ratio of the total mass of the solvent to the total mass of the acyl chloride is 4:1 to 15:1, for example, 8:1 to 12:1, specifically 8:1, 9:1, 10:1, 11:1 or 12:1. The total mass of the solvent is the sum of the mass of the solvent added in step (1), the solvent contained in the first acyl chloride solution, and the solvent contained in the second acyl chloride solution. Adjusting the ratio of solvent to acyl chloride allows for precise control of the amount of acyl chloride monomer added to the reaction system.

[0040] According to an embodiment of the present invention, the ratio of the total molar number of Lewis bases to the total molar number of acyl chlorides is 1.5:1 to 3.0:1, for example, it can be 1.5:1, 2:1, 2.5:1 or 3:1. The total molar number of Lewis bases refers to the total number of Lewis bases in the first and second portions of raw materials added. The total molar number of acyl chlorides refers to the total number of acyl chlorides in the first and second acyl chloride solutions added. This further improves the quality of the obtained polyetherketone ketone. The ratio of Lewis bases to acyl chlorides directly determines the activity and selectivity of the catalytic system. If the ratio is too small, such as less than 1.5:1, excess free Lewis acid will trigger side reactions such as cross-linking, leading to a decrease in molecular weight and a wider distribution. If the ratio is too large, such as greater than 3.0:1, excess Lewis bases will terminate chain growth, similarly limiting the increase in molecular weight. Excess Lewis bases will consume Lewis acid, significantly reducing its activation of acyl chlorides and catalytic effect. Controlling the ratio within the above-mentioned preferred range can ensure the full formation of active catalytic complexes while avoiding side reactions and chain termination, which is the key to achieving high molecular weight, narrow distribution PEKK.

[0041] According to an embodiment of the present invention, M 路易斯酸总摩尔 :(M 酰氯总摩尔 +M 路易斯碱总摩尔 The ratio can be 1.2:1 to 2.0:1. For example, it can be 1.2:1, 1.3:1, 1.4:1, 1.5:1, 1.6:1, 1.7:1, or 1.8:1. Where M... 路易斯酸总摩尔 M represents the total molar number of Lewis acids in the first and second batches of feedstock. 酰氯总摩尔 M represents the total number of moles of acyl chloride in the first and second acyl chloride solutions. 路易斯碱总摩尔 This refers to the total molar number of Lewis bases in the first and second batches of raw materials. This can further improve the quality of the obtained polyetherketone ketone.

[0042] According to an embodiment of the present invention, the ratio of the molar number of added diphenyl ether to the total molar number of acyl chlorides is 0.8:1 to 1.2:1. For example, it can be 0.8:1, 0.9:1, 1:1, 1.1:1, or 1.2:1. The total molar number of acyl chlorides refers to the total number of molars of acyl chlorides in the first and second acyl chloride solutions. This further improves the quality of the obtained polyetherketoneketone. This ratio approaches the theoretical stoichiometric ratio of 1:1, aiming to ensure that the two key monomers participate in polymerization as synchronously and equally as possible, thereby maximizing the growth efficiency and length of the polymer chain. When the ratio is unbalanced (where one component is in excess), premature chain termination occurs because monomers are more efficient and reactive than polymers. This means a polymer chain preferentially reacts with a monomer for chain extension rather than the two polymers reacting for chain expansion, making it difficult to further increase the molecular weight and resulting in a wider molecular weight distribution. For example, when diphenyl ether is in severe excess, a large number of unreacted diphenyl ether molecules act as chain terminators, occupying the active ends of the growing chains and hindering further polymerization, similarly preventing an effective increase in molecular weight. Simultaneously, excess diphenyl ether remains in the product as a difficult-to-remove impurity, reducing the polymer's glass transition temperature, thermal stability, and the mechanical properties of the final product.

[0043] According to an embodiment of the present invention, the mass ratio of the solvent to the acyl chloride in the first and second acyl chloride solutions is 1:1 to 3:1, for example, 1:1, 1.2:1, 1.3:1, 1.4:1, 1.5:1, 1.6:1, 1.7:1, 1.8:1, 1.9:1, 2:1, 2.5:1, or 3:1. This further improves the quality of the obtained polyetherketoneketone.

[0044] According to an embodiment of the present invention, the quality of the polyetherketone ketone obtained by the method can be further improved by adjusting the proportions of the materials added to the reaction system. For example, the mass ratio of Lewis acid in the first part of the raw material to Lewis acid in the second part of the raw material is (6-8):(4-2), for example, 6:4, 7:3, or 8:2. Alternatively, the molar ratio of Lewis base in the first part of the raw material to Lewis base in the second part of the raw material is (6-8):(4-2), for example, 6:4, 7:3, or 8:2. Alternatively, the molar ratio of acyl chloride in the first acyl chloride solution to the molar ratio of acyl chloride in the second acyl chloride solution is (6-8):(4-2), for example, 6:4, 7:3, or 8:2. Thus, the quality of the obtained polyetherketone ketone can be further improved.

[0045] According to embodiments of the present invention, the acyl chloride may be selected from one, two, or three of terephthaloyl chloride, phthaloyl chloride, and isophthaloyl chloride. The Lewis base may be selected from one, two, or more of N,N-dimethylformamide, dimethylacetamide, diphenyl sulfone, triphenylphosphine oxide, nitropropane, sulfolane, dimethyl sulfoxide, dimethyl sulfone, N-methylpyrrolidone, anhydrous lithium chloride, and anhydrous sodium chloride, for example, N,N-dimethylformamide. The Lewis acid may include one, two, or more of anhydrous aluminum trichloride, anhydrous ferric chloride, boron trifluoride, anhydrous zinc dichloride, anhydrous antimony pentachloride, and anhydrous tin dichloride, for example, anhydrous aluminum trichloride. The solvent may include one, two, or more of dichloromethane, dichloroethane, o-dichlorobenzene, carbon disulfide, and nitrobenzene, for example, at least one of dichloromethane and dichloroethane. This further improves the quality of the obtained polyetherketone ketone.

[0046] According to an embodiment of the present invention, the first acyl chloride solution includes terephthaloyl chloride, and the concentration of the terephthaloyl chloride in the first acyl chloride solution is 25% to 50%; the second acyl chloride solution includes isophthaloyl chloride, and the concentration of the isophthaloyl chloride in the second acyl chloride solution is 25% to 50%. Based on the difference in reactivity between terephthalamide and isophthalamide, a method of adding terephthaloyl chloride at a low temperature followed by adding isophthaloyl chloride at a high temperature is specifically designed. The low-temperature environment can slow down the reaction rate of the highly reactive terephthaloyl chloride, avoiding a sudden increase in local monomer concentration due to excessively rapid reaction, thereby further improving the quality of the obtained polyetherketone ketone.

[0047] According to an embodiment of the present invention, the ratio of the total moles of acyl chloride in the first acyl chloride solution to the total moles of acyl chloride in the second acyl chloride solution is (6-8):(4-2), for example, it can be 6:4, 7:3 or 8:2. This further improves the quality of the obtained polyetherketoneketone.

[0048] According to an embodiment of the present invention, the first temperature can be low, such as below zero, specifically -25℃ to 0℃, such as -25℃, -20℃, -15℃, -10℃, etc. The second temperature can be higher, such as 15℃ to 25℃, specifically 20℃. The time for maintaining the first temperature in step (2) can be 0.5 to 1.5 hours, such as 1 hour. In step (3), after the second acyl chloride solution is added dropwise, the reaction is carried out for a period of time, such as 3 to 5 hours. The reaction can be carried out under stirring conditions. Thus, the quality of the obtained polyether ketone ketone can be further improved.

[0049] According to an embodiment of the present invention, after step (3), the process further includes stopping stirring, adding a terminating agent such as hydrochloric acid (which can be dilute hydrochloric acid, specifically 1% to 10% concentration), and allowing it to stand for 4 to 10 hours. This further improves the quality of the obtained polyetherketone ketone.

[0050] According to an embodiment of the present invention, the method further includes: sequentially crushing, sieving, and washing the reaction product, wherein the crushing process includes grinding and pulverizing, and the washing process includes water washing, organic solvent washing, and acid washing, specifically water washing, methanol washing, and dilute hydrochloric acid washing sequentially. This can further improve the quality of the obtained polyether ketone.

[0051] According to an embodiment of the present invention, the method may include the following specific operational steps:

[0052] 1) Install a thermometer, stirrer, and gas delivery tube on the reaction vessel, such as a four-necked flask. Place the apparatus in a cryogenic bath and set the temperature to the first temperature, such as -20°C. Connect the nitrogen flow meter to the nitrogen pipeline, turn on the nitrogen gas, and continuously introduce nitrogen through the gas delivery tube for at least 30 minutes to remove air from the reaction flask and keep the reaction system dry.

[0053] 2) Weigh a certain proportion of Lewis base, Lewis acid, diphenyl ether, and solvent into a four-necked flask and start stirring. The Lewis base, Lewis acid, diphenyl ether, and solvent are as described above.

[0054] 3) Prepare a first acyl chloride solution by mixing acyl chloride with a solvent, and add a certain proportion of the first acyl chloride solution to a four-necked flask at a certain dropping rate. Keep the flask at -20°C for 1 hour, then raise the temperature to 20°C and add a certain proportion of Lewis acid and Lewis base to the four-necked flask. Prepare a second acyl chloride solution by mixing acyl chloride with a solvent, and add a certain proportion of the second acyl chloride solution to the four-necked flask at a certain dropping rate. Stir for 3-5 hours after the addition is complete.

[0055] The acyl chloride is any one or a mixture of several of terephthaloyl chloride, phthaloyl chloride, and isophthaloyl chloride. The mass ratio of the total solvent to the total acyl chloride can be selected between 4:1 and 15:1, preferably 10:1. The total solvent is the sum of the mass of the solvent added in step (2) and the solvent used to prepare the acyl chloride solution in step (3).

[0056] In step (3), the total solvent content of the acyl chloride solution and the mass ratio of the acyl chloride can be selected from 1:1 to 3:1, preferably 1.5:1. In step (3), the mass ratio of the acyl chloride solution added before heating to the acyl chloride solution added after heating is 7:3. The molar ratio of the Lewis acid added in step (2) to the Lewis acid added in step (3) is 7:3. The molar ratio of the Lewis base added in step (2) to the Lewis base added in step (3) is 7:3. The molar ratio of the acyl chloride solution added dropwise before heating to the acyl chloride solution added dropwise after heating in step (3) is 7:3. The molar ratio of the total Lewis base content to the total acyl chloride content can be selected from 1.5:1 to 3.0:1, preferably 2.5:1.

[0057] The molar ratio of the total Lewis acid to the sum of the total acyl chloride and the total Lewis base can be selected from 1.2:1 to 2.0:1, preferably 1.5:1. The molar ratio of diphenyl ether to the total acyl chloride can be selected from 0.8:1 to 1.2:1, preferably 1:1. The rate of addition of the first acyl chloride solution before heating is 2.2% vol to 6.6% vol per minute, preferably 3.4% vol per minute. The rate of addition of the second acyl chloride solution after heating is 2.2% vol to 6.6% vol per minute, preferably 3.4% vol per minute.

[0058] 4) Stop stirring, add 1%~10% dilute hydrochloric acid to decomplex, let stand for 4~10 hours to obtain a gel-like polymer.

[0059] 5) After grinding, crushing and sieving the above-mentioned colloidal polymer, wash it with deionized water, methanol and 1%~10% hydrochloric acid respectively to obtain crude PEKK.

[0060] The core of this invention lies in utilizing the difference in reactivity between terephthaloyl chloride and isophthaloyl chloride, and controlling the sequence through a stepwise feeding and temperature regulation strategy: first, the more reactive terephthaloyl chloride is added at a low temperature, followed by the addition of isophthaloyl chloride at a higher temperature. Furthermore, the specific molar ratio of the two is also a key design parameter for achieving the purpose of this invention. The low-temperature environment slows down the reaction rate of the highly reactive terephthaloyl chloride, preventing a sudden increase in local monomer concentration due to excessively rapid reaction. Combined with a preferred dropping rate, this ensures uniform dispersion of monomers in the system, avoiding uneven molecular chain growth or aggregation reactions, effectively reducing the molecular weight distribution of the finished product, making the product molecular weight more uniform, and thus ensuring the stability of material properties in subsequent processing. Regarding improved reaction efficiency, this invention eliminates the repetitive cycle of "cooling-monomer addition-heating" commonly used in related technologies. Instead, the device is simply fixed in a -20°C cryogenic bath, continuously purged with nitrogen for at least 30 minutes to ensure system dryness, and then heated to 20°C to complete the subsequent addition of isophthaloyl chloride. This eliminates the need for repeated temperature parameter switching, reducing equipment complexity and temperature adjustment waiting time, significantly shortening the overall reaction cycle, improving production efficiency, reducing operational difficulty, minimizing the impact of human factors on the reaction, and ensuring batch-to-batch product quality consistency. Simultaneously, the use of dilute hydrochloric acid for decomposition combined with a specific cleaning sequence effectively removes residual impurities, improves product purity, and further ensures stable finished product performance. Finally, by clearly defining the parameters and processes at each stage, this invention reduces raw material waste caused by side reactions (such as agglomeration and short chains), improving raw material utilization. The simplified process route and parameters make it easier to match the requirements of continuous industrial production, providing strong support for large-scale application.

[0061] In summary, this invention effectively overcomes common problems in traditional PEKK synthesis, such as difficulty in reaction control, wide molecular weight distribution, and non-uniform product structure, through a phased feeding and dropwise addition strategy. It has comprehensive advantages such as stable reaction process, controllable product structure, and good process repeatability, providing a reliable path for the large-scale preparation of high-performance PEKK.

[0062] The following describes embodiments of this application. The embodiments described below are exemplary and are only used to explain this application, and should not be construed as limiting this application. Where specific techniques or conditions are not specified in the embodiments, they are performed according to the techniques or conditions described in the literature in this field or according to the product instructions. Reagents or instruments used, unless otherwise specified, are all conventional products that can be obtained commercially.

[0063] Example 1

[0064] Install a thermometer, stirrer, and gas delivery tube on a four-necked flask. Place the apparatus in a cryogenic bath at -20°C. Connect the nitrogen flow meter to the nitrogen pipeline, turn on the nitrogen gas, and continuously introduce nitrogen through the gas delivery tube for at least 30 minutes to remove air from the reaction flask and keep the reaction system dry. Turn on the stirrer. Weigh 220.5 g of Lewis acid anhydrous aluminum trichloride, 76.8 g of diphenyl ether, 778.6 g of dichloroethane, and 52.5 g of Lewis base N,N-dimethylformamide and add them sequentially to the four-necked flask. Weigh 64 g of terephthaloyl chloride and 96.18 g of dichloroethane to prepare an acyl chloride solution, and add the solution dropwise to the flask at a rate of 3.4% vol per minute. Keep the system at this temperature for 1 hour. After that, add... Heat to 20℃, weigh 94.5g of Lewis acid anhydrous aluminum trichloride and 22.5g of Lewis base N,N-dimethylformamide and put them into a four-necked flask. Then weigh 27.6g of isophthaloyl chloride and 41.22g of dichloroethane to prepare an acyl chloride solution. Add the acyl chloride solution dropwise into the flask at a rate of 3.4% vol per minute. After the addition is complete, keep stirring. After reacting for 4 hours, stop stirring, add 5% dilute hydrochloric acid to decomplex, and let stand for 10 hours to obtain a colloidal polymer. Grind, pulverize and sieve the polymer, and wash it with deionized water, methanol and 5% hydrochloric acid respectively to obtain crude PEKK.

[0065] Example 2

[0066] The remaining operations are the same as in Example 1, except that the acyl chloride solution is added to the flask at a rate of 2.2% vol per minute.

[0067] Example 3

[0068] The remaining operations are the same as in Example 1, except that the acyl chloride solution is added to the flask at a rate of 6.6% vol per minute.

[0069] Example 4

[0070] The remaining operations are the same as in Example 1, except that the Lewis acid added for the first time is 252g, the Lewis base is 60g, and the terephthaloyl chloride is 73.28g; the Lewis acid added for the second time is 63g, the Lewis base is 15g, and the isophthaloyl chloride is 18.32g.

[0071] Example 5

[0072] The remaining operations are the same as in Example 1, except that 229.0 g of dichloroethane was added at the beginning of the reaction, 96.0 g of dichloroethane was added to prepare a solution with terephthaloyl chloride, and 41.4 g of dichloroethane was added to prepare a solution with isophthaloyl chloride.

[0073] Example 6

[0074] The remaining operations are the same as in Example 1, except that 1223.4 g of dichloroethane was added at the beginning of the reaction, 96.0 g of dichloroethane was added to prepare a solution with terephthaloyl chloride, and 41.4 g of dichloroethane was added to prepare a solution with isophthaloyl chloride.

[0075] Example 7

[0076] The remaining operations are the same as in Example 1, except that the mass of the added diphenyl ether is 61.4g.

[0077] Example 8

[0078] The remaining operations are the same as in Example 1, except that the mass of the added diphenyl ether is 92.2g.

[0079] Comparative Example 1

[0080] The remaining operations are the same as in Example 1, except that the acyl chloride solution is added to the flask at a rate of 1.66% vol per minute.

[0081] Comparative Example 2

[0082] The remaining operations are the same as in Example 1, except that the acyl chloride solution is added to the flask at a rate of 33.4% vol per minute.

[0083] Comparative Example 3

[0084] Install a thermometer, a stirrer, and a gas delivery tube on a four-necked flask. Place the apparatus in a cryogenic bath and set the temperature to -20°C. Connect the nitrogen flow meter to the nitrogen pipeline, turn on the nitrogen gas, and continuously introduce nitrogen gas through the gas delivery tube to replace the air in the reaction flask for at least 30 minutes, keeping the reaction system dry. Turn on the stirrer. Weigh 315g of Lewis acid anhydrous aluminum trichloride, 76.8g of diphenyl ether, 778.6g of dichloroethane, and 75g of Lewis base N,N-dimethylformamide and add them sequentially to a four-necked flask. Weigh 27.6g of isophthaloyl chloride, 64g of terephthaloyl chloride, and 137.4g of dichloroethane to prepare an acyl chloride solution, and add it dropwise to the flask at a rate of 1.7% vol per minute. Keep the temperature for 1 hour, then heat the system to 20°C and keep stirring. After reacting for 4 hours, stop stirring, add dilute hydrochloric acid to decomposite, and let stand for 10 hours to obtain a gel-like polymer. Grind, pulverize, and sieve the polymer, and wash it with deionized water, methanol, and 5% hydrochloric acid to obtain crude PEKK.

[0085] Comparative Example 4

[0086] Add 50g AlCl3, 300mL dichloroethane, and 12.5mL N2 to a 500mL three-necked flask equipped with a magnetic stirrer and a nitrogen delivery tube. Methylpyrrolidone and 16 mL of diphenyl ether were cooled to -10°C to -5°C.

[0087] Weigh 4.06g of terephthaloyl chloride and 15mL of dichloroethane, 4.06g of isophthaloyl chloride and 15mL of dichloroethane, and 12.8g of terephthaloyl chloride and 30mL of dichloroethane respectively, and dissolve them to prepare the first terephthaloyl chloride solution, the isophthaloyl chloride solution, and the second terephthaloyl chloride solution for later use;

[0088] While stirring, the first terephthaloyl chloride solution was added dropwise. After the addition was completed within 30 minutes, the reaction was carried out at this temperature for 20 minutes, and then the temperature was raised to 22°C and the reaction was carried out for 1 hour.

[0089] Cool down again to -10℃ to -5℃, and add isophthaloyl chloride solution dropwise while stirring. After the addition is completed within 30 minutes, react at this temperature for 20 minutes, and then raise the temperature to 22℃ and react for 1 hour.

[0090] The temperature was lowered again to -10℃ to -5℃, and the second terephthaloyl chloride solution was added dropwise while stirring. After the addition was completed within 30 minutes, the reaction was carried out at this temperature for 20 minutes, and then the temperature was raised to 22℃ and the reaction was carried out for 2 hours.

[0091] The product was quenched with 50 mL of methanol to obtain a white colloid. After crushing, it was washed sequentially with hydrochloric acid, methanol, and deionized water. Finally, the product was placed in an oven and dried at 150 °C to constant weight to obtain polyether ketone powder.

[0092] Comparative Example 5

[0093] Install a thermometer, stirrer, and gas delivery tube on a four-necked flask. Place the apparatus in a cryogenic bath and set the temperature to -20°C. Connect the nitrogen flow meter to the nitrogen pipeline, turn on the nitrogen gas, and continuously introduce nitrogen through the gas delivery tube for at least 30 minutes to remove air from the reaction flask and keep the reaction system dry. Turn on the stirrer. Weigh 315.0 g of Lewis acid anhydrous aluminum trichloride, 76.8 g of diphenyl ether, 778.6 g of dichloroethane, and 75.0 g of Lewis base N,N-dimethylformamide and add them sequentially to the four-necked flask. Weigh 64 g of terephthaloyl chloride and 96.18 g of dichloroethane to prepare an acyl chloride solution, and add 3.4% volumetric acid of this acyl chloride solution dropwise at a rate of [missing value] per minute. The solution was added dropwise to the flask at a rate of l, and kept at the temperature for 1 hour. Then the system was heated to 20°C. Subsequently, 27.6 g of isophthaloyl chloride and 41.22 g of dichloroethane were weighed to prepare an acyl chloride solution. The solution was added dropwise to the flask at a rate of 3.4% vol per minute. After the addition was completed, the mixture was stirred. After reacting for 4 hours, the stirring was stopped, and 5% dilute hydrochloric acid was added to decomposite the polymer. After standing for 10 hours, a gelatinous polymer was obtained. The polymer was then ground, pulverized, and sieved. After washing with deionized water, methanol, and 5% hydrochloric acid, respectively, crude PEKK was obtained.

[0094] Table 1

[0095]

[0096] Example 1, as the optimal solution of the present invention, involves first adding terephthaloyl chloride solution dropwise at a rate of 3.4% vol per minute at -20°C, maintaining the temperature, then raising the temperature to 20°C. A second batch of Lewis acid and Lewis base is then added, with isophthaloyl chloride solution added dropwise at the same rate. The total dropwise addition time is 1 hour. The corresponding molecular weight data exhibits the best uniformity—the number-average molecular weight (Mn) reaches 40640, the highest among all cases; the weight-average molecular weight (Mw) is 165538; the polydispersity index (PDI) is only 4.073 (the lowest among all cases); the peak molecular weight (Mp) is 55632; the Z-average molecular weight (Mz) is 685077; and Mz+1 is 1443902, all within a reasonable range. This result stems from a temperature-controlled feeding experimental design based on the differences in the reactivity of the two acyl chlorides: terephthaloyl chloride has higher reactivity, and the low-temperature environment can slow down its reaction rate, avoiding a sudden increase in local monomer concentration. A dropping rate of 3.4% vol / min ensures that the monomer is uniformly dispersed in the system, preventing uneven molecular chain growth due to slow monomer replenishment, which would result in a wide molecular weight distribution of the product, or disordered growth or agglomeration of molecular chains due to local excess caused by excessive dropping rate. Stepwise feeding allows isophthaloyl chloride to react fully at high temperature, complementing the reaction process of terephthaloyl chloride, ultimately achieving controllable molecular chain growth and narrowing the molecular weight distribution.

[0097] Examples 2 and 3 are supporting examples of adjusting the dropping rate of acyl chloride based on Example 1. In Example 2, the dropping rate was reduced to 2.2% vol per minute, and the total dropping time was 1.5 hours. The remaining operations were completely consistent with Example 1. The molecular weight indicators decreased—Mn decreased to 36646, PDI increased to 4.378, and although Mw, Mz, and Mz+1 were close to those of Example 1 (160456, 680466, and 1431851, respectively), the uniformity of the molecular chains was not as good as in Example 1. The reason is that the slow dropping rate and slow monomer replenishment led to uneven molecular chain growth, resulting in a wide molecular weight distribution of the product. Example 3 increased the dropping rate to 6.6% vol per minute, with a total dropping time of 0.5 hours. Mn further decreased to 34530, PDI increased to 4.516, and Mw, Mz, and Mz+1 slightly decreased (155954, 653361, 1365106). This was because the excessively fast dropping rate prevented the acyl chloride solution from mixing with the system in time, resulting in excessively high monomer concentrations in localized areas, triggering a violent reaction. This not only generated short-chain molecules but also caused a small amount of aggregation, leading to insoluble solids in the system, resulting in a decrease in molecular weight and a further broadening of the molecular weight distribution. Although Examples 2 and 3 experienced a performance decrease due to the dropping rate deviating from the optimal value, their PDIs were still lower than all comparative examples, indicating that stepwise feeding as the core strategy provided a fundamental guarantee for molecular weight uniformity. The difference between Examples 2 and 3 is that Example 2 had a slower acyl chloride dropping rate, resulting in more uniform monomer dispersion and a more controllable reaction compared to Example 3, with a narrower molecular weight distribution. Example 3 had a faster dropping rate, leading to a sudden increase in local monomer concentration, a violent reaction, more short chains, and a wider molecular weight distribution.

[0098] Comparative Examples 1 to 4 demonstrate the advantages of this invention from three dimensions: uncontrolled dropping rate, incorrect feeding method, and complex process. Comparative Example 1 reduced the acyl chloride dropping rate to 1.66% vol per minute, with a total dropping time of 2 hours. Although stepwise feeding was maintained, the excessively slow dropping rate resulted in slow monomer replenishment, leading to uneven molecular chain growth and a wide molecular weight distribution of the product. Consequently, Mn was only 29487, far lower than the three examples, PDI soared to 5.108, and Mw was 150644 and Mz was 667413, also significantly lower than Example 1. This indicates that even with controlled dropping rate, the invention still has advantages. Even with stepwise feeding, a drop rate that is too low can still severely disrupt the molecular weight distribution. Comparative Example 2 employed a rapid dropping strategy of adding 33.4% vol per minute over a total of 0.1 hours. Although Mp (56910) was slightly higher than in Example 1, Mn was only 27279, the lowest among all examples, and PDI was as high as 6.129, the highest among all examples. While Mw (167203), Mz (720845), and Mz+1 (1492148) were not low, they reflected a chaotic state in which short-chain and extremely long-chain molecules coexisted in the system. The reason for the poor molecular weight uniformity in the first example is that the excessively rapid dropping rate caused the acyl chloride to concentrate instantaneously, leading to localized uncontrolled reactions. The system contained both a large number of insufficiently grown short chains and ultra-long chains formed by aggregation. In the second example, the stepwise addition of Lewis acid, Lewis base, and both acyl chlorides was eliminated, and all were added to the system at once. The Mn (28346) and Mw (149804) were both low, and the PDI was 5.284. This is because the highly reactive terephthaloyl chloride reacted instantaneously with the diphenyl ether at low temperature, generating a large number of short-chain products, while the terephthaloyl chloride, due to its high activity... The low reactivity of the two acyl chlorides means they cannot fully participate in the reaction in a single feeding, resulting in raw material waste and uneven molecular chain growth. This directly confirms the necessity of stepwise temperature-controlled feeding to match the differences in activity between the two acyl chlorides. Comparative Example 4 used more complex temperature and dropping conditions, the core problem of which was the cumbersome process. Although a certain degree of molecular weight uniformity could be achieved through multiple temperature controls, the frequent temperature switching not only prolonged the reaction cycle but also increased the complexity of equipment operation and the risk of human error, making it difficult to ensure the consistency of product quality between batches, and the molecular weight distribution was very wide. In contrast, Example 1 of this invention has a simplified process and a shorter cycle. At the same time, through precise dropping rate and stepwise feeding, it achieves better molecular weight uniformity and production stability than Comparative Example 4.

[0099] In summary, the embodiments of the present invention, especially Embodiment 1, through the segmented temperature-controlled feeding strategy, are superior to the comparative embodiment in terms of molecular weight uniformity and reaction efficiency, fully demonstrating its technical advantages and industrial application value.

[0100] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A method for preparing polyetherketoneketone, characterized in that, include: (1) The first part of the raw material, diphenyl ether, and solvent are mixed and added to the reaction vessel at a first temperature. The first part of the raw material includes a portion of Lewis acid and a portion of Lewis base. The Lewis base is selected from at least one of N,N-dimethylformamide, dimethylacetamide, and N-methylpyrrolidone. (2) The first acyl chloride solution is added to the reaction vessel at a first drop rate, while maintaining the first temperature; (3) After heating to the second temperature, add the second part of the raw materials, and add the second acyl chloride solution dropwise at the second drop rate. The second part of the raw materials includes the remaining Lewis acid and the remaining Lewis base. The second temperature is higher than the first temperature. The molar ratio of Lewis acid in the first part of the raw material to Lewis acid in the second part of the raw material is (6-8):(4-2), the molar ratio of Lewis base in the first part of the raw material to Lewis base in the second part of the raw material is (6-8):(4-2), the mass ratio of acyl chloride in the first acyl chloride solution to the mass ratio of acyl chloride in the second acyl chloride solution is (6-8):(4-2), the mass ratio of solvent in the first acyl chloride solution and the second acyl chloride solution to the mass ratio of acyl chloride is 1:1 to 3:1, the ratio of the number of moles of diphenyl ether added to the total number of moles of acyl chloride is 0.8:1 to 1.2:1, and the total number of moles of acyl chloride is the total number of moles of acyl chloride in the first acyl chloride solution and the second acyl chloride solution added; The acceleration rate of the first drop was 2.2% vol / min to 6.6% vol / min. The acceleration rate of the second drop was 2.2% vol / min to 6.6% vol / min.

2. The method according to claim 1, characterized in that, Both the first acyl chloride solution and the second acyl chloride solution include the solvent. The ratio of the total mass of the solvent to the total mass of the solute acyl chlorides in the first and second acyl chloride solutions is 4:1 to 15:

1. The total mass of the solvent is the sum of the mass of the solvent added in step (1), the mass of the solvent contained in the first acyl chloride solution, and the mass of the solvent contained in the second acyl chloride solution.

3. The method according to claim 2, characterized in that, The ratio of the total mass of the solvent to the total mass of the solute acyl chloride in the first and second acyl chloride solutions is 10:

1.

4. The method according to claim 1, characterized in that, M 路易斯碱总摩尔 M 酰氯总摩尔 The ratio is from 1.5:1 to 3.0:1, and / or M 路易斯酸总摩尔 :(M 酰氯总摩尔 +M 路易斯碱总摩尔 The ratio is 1.2:1 to 2.0:

1. Wherein, the M 路易斯碱总摩尔 M is the total molar number of Lewis bases in the first and second portions of raw materials added; 酰氯总摩尔 M represents the total number of moles of acyl chloride in the first and second acyl chloride solutions added; 路易斯酸总摩尔 The total number of moles of Lewis acid in the first and second portions of raw materials added.

5. The method according to claim 4, characterized in that, M 路易斯碱总摩尔 M 酰氯总摩尔 The ratio is 2.5:1, and / or M 路易斯酸总摩尔 :(M 酰氯总摩尔 +M 路易斯碱总摩尔 The ratio is 1.5:

1.

6. The method according to claim 1, characterized in that, The ratio of the molar amount of the added diphenyl ether to the total molar amount of the added acyl chloride is 1:

1.

7. The method according to claim 6, characterized in that, The mass ratio of the solvent to the acyl chloride in the first acyl chloride solution and the second acyl chloride solution is 1.5:

1.

8. The method according to claim 1, characterized in that, The solute acyl chlorides in the first acyl chloride solution and the second acyl chloride solution are each independently selected from one, two, or three of terephthaloyl chloride, phthaloyl chloride, and isophthaloyl chloride; The solvent includes one, two, or more of dichloromethane, dichloroethane, o-dichlorobenzene, carbon disulfide, and nitrobenzene.

9. The method according to claim 8, characterized in that, The first acyl chloride solution includes terephthaloyl chloride, and the concentration of the terephthaloyl chloride in the first acyl chloride solution is 25% to 50%; The second acyl chloride solution comprises isophthaloyl chloride, wherein the concentration of the isophthaloyl chloride in the second acyl chloride solution is 25% to 50%; and / or The ratio of the total number of moles of acyl chloride in the first acyl chloride solution to the total number of moles of acyl chloride in the second acyl chloride solution is (6-8):(4-2).

10. The method according to claim 1, characterized in that, Before adding the first portion of raw materials, diphenyl ether, and solvent to the reaction vessel, the temperature of the reaction vessel is pre-cooled and an inert gas is introduced. The inert gas includes one, two, or three of nitrogen, argon, and neon; and / or The first temperature is -25℃ to 0℃, and the second temperature is 15℃ to 25℃; In step (2), maintain the first temperature for 0.5 to 1.5 hours; In step (3), the reaction is carried out for 3-5 hours after the second acyl chloride solution is added; and / or Step (3) further includes adding hydrochloric acid as a stop agent and allowing it to stand for 4 to 10 hours; and / or The method further includes: sequentially crushing, sieving, and washing the reaction products. The crushing process includes grinding and pulverizing, and the washing process includes water washing, organic solvent washing, and acid washing.

11. A polyether ketone ketone, characterized in that, The polyether ketone ketone is prepared by the method according to any one of claims 1-10, wherein the molecular weight distribution coefficient of the polyether ketone ketone is between 2.5 and 4.6, and the weight-average molecular weight is between 15w and 16w.

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