A polyaryletherketone copolymer and its preparation method

Abstract

This application relates to a polyaryletherketone copolymer and a method for preparing the same. The polyaryletherketone copolymer is basically composed of repeating units of Formula I and repeating units of Formula II: O-Ph-O-Ph-CO-Ph Formula IO-Ph-Ph-O-Ph-CO-Ph Formula II; wherein the molar ratio of the repeating units of Formula I to the repeating units of Formula II is 50:50 to 95:5, preferably 60:40 to 90:10, more preferably 70:30 to 85:15; and the polydispersity index (PDI) of the polyaryletherketone copolymer is at most 2.7, preferably at most 2.65, more preferably at most 2.6, and most preferably at most 2.55.

Description

Technical Field

[0001] This application belongs to the field of polymer materials technology and relates to a polyaryletherketone copolymer and its preparation method. Background Technology

[0002] Polyaryletherketones (PAEKs), including polyetheretherketones (PEEK), polyetherketones (PEK), polyetherketoneketones (PEKK), and polyaryletherketone copolymers (PEEK-PEDEK), are a class of semi-crystalline thermoplastic polymers whose molecular backbone is composed of arylene groups, ether bonds, and ketone bonds. Due to their excellent high-temperature resistance, superior mechanical strength, outstanding chemical corrosion resistance, good flame retardancy, and radiation resistance, they are widely used in high-end fields such as aerospace, automotive manufacturing, electronics, and medical implants.

[0003] Currently, the most common industrial method for synthesizing polyaryletherketones (PAKs) is nucleophilic substitution polycondensation, which involves the polymerization of aromatic difluoro monomers and diphenols in a polar aprotic solvent under high temperature and an inert atmosphere to form a polymer. The traditional one-pot process involves adding all monomers (one or more diphenols, one or more aromatic difluoro monomers), solvents, and salt-forming agents to the same reactor at once. This one-pot method typically suffers from the following problems in preparing PAK copolymers: competitive salt formation, random structure of the resulting copolymer, increased side reactions, and difficulty in achieving high molecular weights.

[0004] Therefore, it is of great significance to develop a synthetic method that can overcome competitive salt formation, achieve controlled polymerization, and effectively suppress side reactions to obtain high molecular weight and structurally regular polyarylether ketone copolymers. Summary of the Invention

[0005] The purpose of this application is to provide a polyaryletherketone copolymer and a method for preparing the same.

[0006] The first aspect of this application provides a polyaryletherketone copolymer, which is essentially composed of repeating units of Formula I and repeating units of Formula II: O-Ph-O-Ph-CO-Ph Formula I O-Ph-Ph-O-Ph-CO-Ph Formula II Wherein, the molar ratio of the repeating unit of Formula I to the repeating unit of Formula II is 50:50 to 95:5, preferably 60:40 to 90:10, more preferably 70:30 to 85:15; and The polydispersity index (PDI) of the polyaryletherketone copolymer is at most 2.7, preferably at most 2.65, more preferably at most 2.6, and most preferably at most 2.55.

[0007] In some embodiments according to this application, the number-average molecular weight of the polyaryletherketone copolymer is in the range of 18,000 to 35,000, as determined by GPC.

[0008] In some embodiments according to this application, the L value of the polyaryletherketone copolymer is at least 80.0, preferably at least 80.1, more preferably at least 80.2, as determined by a colorimeter; and the b value of the polyaryletherketone copolymer is at most 3.60, preferably at most 3.55, more preferably at most 3.45, and most preferably at most 3.40.

[0009] In some embodiments according to this application, the initial decomposition temperature of the polyaryletherketone copolymer is determined by thermogravimetric analysis to be at least 566°C, preferably at least 568°C, and more preferably at least 569°C.

[0010] In some embodiments according to this application, the gel content of the polyaryletherketone copolymer is determined by filtration method to be at most 0.10%, preferably at most 0.08%, more preferably at most 0.07%, and most preferably at most 0.06%.

[0011] In some embodiments of this application, the absorbance of the concentrated sulfuric acid solution of the polyaryletherketone copolymer at 550 nm is at most 0.170, preferably at most 0.160, and more preferably at most 0.150.

[0012] A second aspect of this application provides a method for preparing the above-mentioned polyaryletherketone copolymer, comprising the following steps: a) Mix the first diphenol monomer in a polar aprotic solvent and heat to form a homogeneous monomer solution; b) Mix the second diphenol monomer in a polar aprotic solvent and heat to form a homogeneous monomer solution; c) In a batch reactor, aromatic difluorine monomers are mixed with a polar aprotic solvent and heated to form a homogeneous monomer solution; d) Mix the salt-forming agent with a polar aprotic solvent; e) The monomer solution obtained in step a) and a portion of the material obtained in step d) undergo a salt formation reaction at 160-180℃ through the first microchannel, with a residence time of 1-20 min; f) The monomer solution obtained in step b) and the remaining material obtained in step d) undergo a salt formation reaction at 180-235℃ through a second microchannel for a residence time of 1-20 min; g) The remaining materials obtained in steps e) and f) are fed into a batch reactor and polycondensed at 280-340°C for 1 to 5 hours to obtain the polyaryletherketone copolymer.

[0013] In some embodiments of this application, the method is carried out in a series system of a batch reactor and a microchannel reactor containing at least two microchannels.

[0014] In some embodiments of this application, the first diphenol is selected from one or more of hydroquinone, resorcinol, catechol, and 2-methyl-1,4-hydroquinone, preferably hydroquinone; the second diphenol is selected from one or more of 2,2'-dihydroxybiphenyl, 3,3'-dihydroxybiphenyl, 4,4'-dihydroxybiphenyl, 1,4-naphthoquinone, 1,5-naphthoquinone, 2,6-naphthoquinone, and 2,7-naphthoquinone, preferably 4,4'-dihydroxybiphenyl.

[0015] In some embodiments according to this application, the salt-forming agent is an alkali metal carbonate or an alkali metal bicarbonate, preferably selected from one or more of potassium carbonate, sodium carbonate, cesium carbonate and potassium bicarbonate, and more preferably selected from one or more of potassium carbonate and sodium carbonate.

[0016] In some embodiments according to this application, the amount of the salt-forming agent is in excess of 1 mol% to 20 mol% relative to the total molar amount of diphenols in the system, preferably in excess of 5 mol% to 20 mol%.

[0017] In some embodiments of this application, the polar aprotic solvent is selected from one or more of diphenyl sulfone, N-methylpyrrolidone and N,N-dimethylacetamide, preferably diphenyl sulfone.

[0018] In some embodiments of this application, the aromatic difluoro monomer is 4,4'-difluorobenzophenone or 2,4'-difluorobenzophenone, preferably 4,4'-difluorobenzophenone.

[0019] In some embodiments according to this application, the particle size of the salt-forming agent is ≤400 micrometers.

[0020] Furthermore, a third aspect of this application relates to polyaryletherketone copolymers obtained by the above method.

[0021] By independently salting different phenol monomers under different reaction conditions, the reactivity was controlled, effectively avoiding competing reactions and side reactions. Furthermore, by using a microchannel reactor for the salting reaction, the salting reaction time was greatly shortened, achieving a major breakthrough in reaction efficiency. This resulted in the synthesis of high molecular weight, narrow distribution, and more regular polyaryletherketone copolymers, which was unforeseen before this application.

[0022] The fourth aspect of this application provides printing materials, particularly 3D printing materials, comprising polyaryletherketone copolymers according to the first or third aspect of this application or polyaryletherketone copolymers prepared by the method according to the second aspect of this application.

[0023] The fifth aspect of this application provides the use of polyaryletherketone copolymers according to the first or third aspect of this application, or polyaryletherketone copolymers prepared by the method according to the second aspect of this application, for the preparation of printing materials, particularly 3D printing materials.

[0024] The sixth aspect of this application provides a prepreg prepared from a polyaryletherketone copolymer according to the first or third aspect of this application or from a polyaryletherketone copolymer prepared by the method according to the second aspect of this application.

[0025] The printing materials and prepregs of this application contain the polyaryletherketone copolymers provided in this application, and therefore have at least the same advantages as the polyaryletherketone copolymers. Attached Figure Description

[0026] Figure 1 A flowchart of a method for preparing polyaryletherketone copolymers according to this application is shown. Detailed Implementation

[0027] The following detailed description, with appropriate reference to the accompanying drawings, discloses embodiments of the polyaryletherketone copolymer and its preparation method thereof. However, unnecessary details may be omitted. For example, detailed descriptions of well-known matters and repetitive descriptions of essentially identical structures may be omitted. This is to avoid unnecessarily lengthy descriptions and to facilitate understanding by those skilled in the art. Furthermore, the accompanying drawings and the following description are provided for the purpose of enabling those skilled in the art to fully understand this application and are not intended to limit the subject matter of the claims.

[0028] The "range" disclosed in this application is defined by a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of a particular range. Ranges defined in this way can include or exclude endpoints and can be arbitrarily combined; that is, any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60-120 and 80-110 are listed for a specific parameter, it is expected that ranges of 60-110 and 80-120 are also included. Furthermore, if minimum range values ​​of 1 and 2 are listed, and if maximum range values ​​of 3, 4, and 5 are listed, then the following ranges are all expected: 1-3, 1-4, 1-5, 2-3, 2-4, and 2-5. In this application, unless otherwise stated, the numerical range "ab" represents a shortened representation of any combination of real numbers between a and b, where a and b are real numbers. For example, the numerical range "0-5" indicates that all real numbers between "0-5" have been listed in this article; "0-5" is simply a shortened representation of these numerical combinations. Furthermore, when a parameter is stated as an integer ≥2, it is equivalent to disclosing that the parameter is, for example, an integer such as 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0029] Unless otherwise specified, all embodiments and optional embodiments of this application may be combined with each other to form new technical solutions, and such technical solutions should be considered to be included in the disclosure of this application.

[0030] Unless otherwise specified, all technical features and optional technical features of this application may be combined to form new technical solutions, and such technical solutions shall be deemed to be included in the disclosure of this application.

[0031] Unless otherwise specified, all steps in this application may be performed sequentially or randomly, preferably sequentially. For example, the method includes steps (a) and (b), indicating that the method may include steps (a) and (b) performed sequentially, or it may include steps (b) and (a) performed sequentially. For example, the method may also include step (c), indicating that step (c) may be added to the method in any order. For example, the method may include steps (a), (b), and (c), or it may include steps (a), (c), and (b), or it may include steps (c), (a), and (b), etc.

[0032] Unless otherwise specified, the terms "comprising" and "including" as used in this application can be open-ended or closed-ended. For example, "comprising" and "including" can mean that other components not listed may also be included, or that only the listed components may be included.

[0033] Unless otherwise specified, the term "or" is inclusive in this application. For example, the phrase "A or B" means "A, B, or both A and B". More specifically, the condition "A or B" is satisfied by any of the following conditions: A is true (or exists) and B is false (or does not exist); A is false (or does not exist) and B is true (or exists); or both A and B are true (or exist).

[0034] Unless otherwise specified, in this application, the terms "first," "second," "third," etc., are used to distinguish different objects, rather than to describe a specific order or primary / secondary relationship.

[0035] In this application, the terms "multiple", "various", etc., refer to two or more kinds.

[0036] Unless otherwise stated, the terms used in this application have the common meanings as commonly understood by those skilled in the art.

[0037] Unless otherwise stated, the values ​​of the parameters mentioned in this application can be determined using various testing methods commonly used in the art, for example, according to the testing methods given in the embodiments of this application. Unless otherwise stated, the test temperature is 25°C.

[0038] Polyaryletherketones (PAGEs) are a class of semi-crystalline thermoplastic polymers whose molecular backbone consists of arylene groups, ether bonds, and ketone bonds. Due to their excellent high-temperature resistance, superior mechanical strength, outstanding chemical corrosion resistance, good flame retardancy, and radiation resistance, they are widely used in high-end fields such as aerospace, automotive manufacturing, electronics, and medical implants. Currently, the most commonly used method for industrial preparation of PAGEs is nucleophilic substitution polymerization. When using diphenol monomers with different reactivity to prepare PAGE copolymers, the traditional one-pot process adds all monomers, solvents, and salt-forming agents to the same reactor at once. This method has the following problems: 1. Competitive salt formation: Diphenol monomers with different reactivity (such as hydroquinone and 4,4'-dihydroxybiphenyl) have different salt formation rates and equilibrium constants with salt-forming agents, resulting in uneven concentrations of phenolic salt active species in the reaction system; 2. Random structure: The difference in nucleophilic substitution activity of different phenol salts causes the monomer units in the copolymer chain to be randomly distributed, making it difficult to obtain a well-structured polymer chain, thereby impairing the crystallinity, melting point and mechanical properties of the product; 3. Increased side reactions: After the highly reactive phenol salts react preferentially, the residual low-reactivity diphenol monomers will lead to a local increase in alkalinity of the reaction medium, which may induce side reactions such as ether bond cleavage, resulting in a wider molecular weight distribution, polymer branching or cross-linking, and may also cause product discoloration. 4. High molecular weight is difficult to achieve: Due to the competition and interference between salt formation and condensation reactions, it is difficult to accurately control the stoichiometric balance, thus making it difficult to obtain ultra-high molecular weight PAEK products.

[0039] To address the aforementioned issues, the inventors of this application conducted extensive experiments and in-depth research, and surprisingly discovered that by independently salting different phenol monomers under different reaction conditions, precise control of reactivity was achieved, effectively avoiding competing reactions and side reactions. By using a microchannel reactor for the salting reaction, the salting reaction time was greatly shortened, achieving a major breakthrough in reaction efficiency, thereby synthesizing high molecular weight, narrow distribution, and more regular sequence structure polyaryletherketone copolymers.

[0040] Therefore, a first aspect of the embodiments of this application provides a polyaryletherketone copolymer, which is basically composed of repeating units of Formula I and repeating units of Formula II: O-Ph-O-Ph-CO-Ph Formula I O-Ph-Ph-O-Ph-CO-Ph Formula II Wherein, the molar ratio of the repeating unit of Formula I to the repeating unit of Formula II is 50:50 to 95:5, preferably 60:40 to 90:10, more preferably 70:30 to 85:15; and The polydispersity index (PDI) of the polyaryletherketone copolymer is at most 2.7, preferably at most 2.65, more preferably at most 2.6, and most preferably at most 2.55.

[0041] In the context of this application, "consistently of" means that, in addition to the listed components, the other components are present in an amount of up to 5% by weight, preferably up to 3% by weight, more preferably up to 1.5% by weight, and most preferably 1% by weight.

[0042] In embodiments of this application, the molar ratio of repeating units of Formula I to repeating units of Formula II in the polyaryletherketone copolymer is 50:50 to 95:5, preferably 60:40 to 90:10, more preferably 70:30 to 85:15, and even more preferably 70:30 to 80:20. Exemplarily, the molar ratio of repeating units of Formula I to repeating units of Formula II in the polyaryletherketone copolymer is 50:50, 55:45, 60:40, 65:35, 70:30, 75:25, 80:20, 85:15, 90:10, etc., or within any range of two of the above values.

[0043] In this paper, the term "polydispersity index (PDI)" is a key parameter used to measure the breadth of the molecular weight distribution of a polymer. Its value is defined as the ratio of the weight-average molecular weight (Mw) to the number-average molecular weight (Mn) of the polymer (PDI = Mw / Mn).

[0044] In embodiments of this application, the polydispersity index (PDI) of the polyaryletherketone copolymer is at most 2.7, preferably at most 2.65, more preferably at most 2.6, and most preferably at most 2.55. Exemplarily, the PDI of the polyaryletherketone copolymer can be 2.7, 2.65, 2.6, 2.55, 2.5, 2.45, 2.4, 2.35, 2.3, 2.25, 2.2, 2.15, etc., or within any range of two of the above values.

[0045] For the polyaryletherketone copolymer described in this application, the characteristic of PDI ≤ 2.7 directly indicates that it has a narrow and controllable molecular weight distribution. This gives it excellent melt stability and rheological behavior during processing, thus enabling the preparation of products with uniform structure and low internal stress. At the same time, the highly uniform molecular chain structure endows the material with more consistent and predictable mechanical strength, thermal stability, and long-term reliability, with overall performance significantly superior to similar materials with wider distributions.

[0046] In this document, the terms "number-average molecular weight" and "weight-average molecular weight" have meanings known in the field of polymer materials and can be determined using instruments and methods known in the art. As an example, gel permeation chromatography (GPC) is used, for instance, with an Agilent Technologies PL-GPC220 High Temperature GPC system, using α-chloronaphthalene as solvent and 1,2,4-trichlorobenzene as diluent; the column temperature is 125°C, and the mobile phase is a mixture of α-chloronaphthalene and 1,2,4-trichlorobenzene (mass ratio of α-chloronaphthalene to 1,2,4-trichlorobenzene = 1:2.2), with K = 14.2 and α = 0.72, to determine the number-average molecular weight of the sample.

[0047] In some embodiments of this application, the number-average molecular weight of the polyaryletherketone copolymer is in the range of 18,000 to 35,000, preferably in the range of 18,000 to 30,000, more preferably in the range of 19,000 to 29,000, and most preferably in the range of 19,000 to 28,000. Exemplarily, the number-average molecular weight of the polyaryletherketone copolymer can be 18,000, 19,000, 20,000, 21,000, 22,000, 23,000, 24,000, 25,000, 26,000, 27,000, 28,000, 29,000, 30,000, 31,000, 32,000, 33,000, 34,000, 35,000, or within any two of the above values. When the number-average molecular weight of the polyaryletherketone copolymer is within the above range, the polyaryletherketone copolymer has appropriate mechanical strength, which is beneficial for forming products with excellent performance.

[0048] In some embodiments of this application, the weight-average molecular weight of the polyaryletherketone copolymer is in the range of 50,000 to 130,000, preferably in the range of 51,000 to 100,000, more preferably in the range of 51,000 to 80,000, and most preferably in the range of 51,000 to 70,000. For example, the weight-average molecular weight of the polyaryletherketone copolymer can be 50,000, 51,000, 51,500, 52,000, 53,000, 54,000, 55,000, 56,000, 57,000, 58,000, 59,000, 60,000, 61,000, 62,000, 63,000, 64,000, 65,000, 70,000, 75,000, 80,000, 85,000, 90,000, 95,000, 100,000, 105,000, 110,000, 115,000, 120,000, 125,000, 130,000, or within any two of the above values. Weight-average molecular weight affects the mechanical, thermal, processing, and final application properties of polyaryletherketone copolymers. When the weight-average molecular weight of the polyaryletherketone copolymer is within the aforementioned range, its overall performance achieves optimal balance. By controlling the weight-average molecular weight within this range, the polyaryletherketone copolymer of this application achieves performance optimization, expanding its application potential in high-end engineering fields.

[0049] In some embodiments of this application, the L value of the polyaryletherketone copolymer is at least 80.0, preferably at least 80.1, more preferably at least 80.2, even more preferably at least 80.3, and most preferably at least 80.5. Exemplarily, measured by a colorimeter, the L value of the polyaryletherketone copolymer can be 80.0, 80.1, 80.2, 80.3, 80.4, 80.5, 80.6, 80.7, 80.8, 80.9, 81.0, 81.1, 81.2, 81.3, 81.4, 81.5, 81.6, 81.7, 81.8, 81.9, 82.0, 82.1, 82.2, 82.3, 82.4, 82.5, 82.6, 82.7, 82... 8, 82.9, 83.0, 83.1, 83.2, 83.3, 83.4, 83.5, 83.6, 83.7, 83.8, 83.9, 84.0, 84.1, 84.2, 84.3, 84.4, 84.5, 84.6, 84.7, 84.8, 84.9, 85.0, 85.5, 86.0, 86.5, 87.0, 87.5, 88.0, 88.5, 89.0, etc., or within the range formed by any two of the above values.

[0050] In color science, the L-value represents lightness, ranging from 0 (pure black) to 100 (pure white). Therefore, the high L-value (at least 80.0) of the polyaryletherketone copolymer directly characterizes the material's extremely high whiteness and visual clarity. This not only signifies excellent color and lower impurity content but also reflects the high precision and controllability of the polymerization and processing. This superior color stability is a comprehensive manifestation of the material's high internal homogeneity, controlled thermal history, and excellent purity, giving it significant aesthetic advantages and reliable quality in fields with stringent requirements for appearance quality, purity, and consistency.

[0051] In some embodiments of this application, the b-value of the polyaryletherketone copolymer is at most 3.60, preferably at most 3.55, more preferably at most 3.45, and most preferably at most 3.40. Exemplarily, measured by a colorimeter, the b-value of the polyaryletherketone copolymer can be 3.60, 3.55, 3.50, 3.45, 3.40, 3.35, 3.30, 3.25, 3.20, 3.15, 3.10, 3.05, 3.00, or within any range of two of the above values.

[0052] In color difference measurement systems, the b-value represents the yellow-blue index, with positive values ​​indicating a yellowish tint and negative values ​​indicating a bluish tint. Therefore, the low b-value (at most 3.60) of the polyaryletherketone copolymer directly characterizes the material's extremely low yellowness, resulting in a highly pure and near-neutral color. This stringent color control not only signifies a premium and clean visual appeal for the product but also reflects the material's excellent thermal stability and anti-aging properties, demonstrating its effective suppression of thermal degradation and yellowing tendencies during synthesis and high-temperature processing. This outstanding color stability gives it a competitive advantage and reliable quality assurance in fields with stringent requirements for appearance consistency, long-term durability, and high-quality perception (such as high-end electronic casings, precision optical components, and high-quality consumer goods).

[0053] In some embodiments of this application, the initial decomposition temperature of the polyaryletherketone copolymer, determined by thermogravimetric analysis, is at least 566°C, preferably at least 568°C, more preferably at least 569°C, and even more preferably at least 570°C. Exemplarily, the initial decomposition temperature of the polyaryletherketone copolymer, determined by thermogravimetric analysis, can be 566°C, 567°C, 568°C, 569°C, 570°C, 571°C, 572°C, 573°C, 574°C, 575°C, 576°C, 577°C, 578°C, 579°C, 580°C, 581°C, 582°C, 583°C, 584°C, 585°C, 586°C, 587°C, 588°C, or within any two of the above values.

[0054] In thermogravimetric analysis, the initial decomposition temperature refers to the temperature at which a material begins to experience significant thermogravimetric loss during a programmed temperature rise, and it is a core indicator for measuring the thermal stability of a material. Therefore, the high initial decomposition temperature (at least 566°C) of the polyaryletherketone copolymer directly characterizes its excellent heat resistance and thermal stability. This strictly controlled parameter not only means that the material can maintain structural integrity and performance stability at higher temperatures, but also reflects, more profoundly, the extremely strong bond energy, excellent chemical stability, and low content of easily decomposable impurities in its polymer chain structure. This thermal stability provides crucial long-term reliability and safety under extreme conditions such as continuous high temperatures, instantaneous high temperatures, or harsh thermal cycling.

[0055] In some embodiments of this application, the gel content of the polyaryletherketone copolymer, as determined by filtration, is at most 0.10%, preferably at most 0.08%, more preferably at most 0.07%, and most preferably at most 0.06%. Exemplarily, the gel content of the polyaryletherketone copolymer, as determined by filtration, is 0.10%, 0.09%, 0.08%, 0.07%, 0.06%, 0.05%, 0.04%, 0.03%, or within any range of two of the above values.

[0056] Gel content refers to the mass percentage of cross-linked or giant molecular networks in a material that are insoluble in a specific solvent. It is a key indicator for measuring the purity and linear structural integrity of a polymer solution or melt. Therefore, the extremely low gel content (at most 0.10%) of the polyaryletherketone copolymer directly characterizes its extremely high chemical purity and highly regular molecular structure. This near-stringent control standard not only ensures excellent flow uniformity and superior film-forming ability during melt processing, but also reflects the high precision and controllability of its synthesis process, effectively avoiding performance defects caused by side reactions or impurities. This purity gives it a competitive advantage in fields with extreme requirements for long-term durability, such as additive manufacturing.

[0057] Additive manufacturing, often referred to as 3D printing, is an advanced manufacturing technology that uses digital model files as a basis and integrates computer-aided design, material processing, and forming technologies. Through software and CNC systems, it uses methods such as extrusion, sintering, melting, photopolymerization, and spraying to build solid objects layer by layer. Unlike traditional manufacturing technologies, additive manufacturing employs a bottom-up material accumulation method, overcoming the limitations of traditional manufacturing in creating complex structural parts and achieving a manufacturing process from scratch. The polyaryletherketone copolymer described in this application is particularly useful for additive manufacturing of parts.

[0058] In some embodiments of this application, the absorbance of the concentrated sulfuric acid solution of the polyaryletherketone copolymer at 550 nm is at most 0.170, preferably at most 0.160, more preferably at most 0.150, and most preferably at most 0.148. For example, the absorbance of the concentrated sulfuric acid solution of the polyaryletherketone copolymer at 550 nm is 0.170, 0.165, 0.160, 0.155, 0.154, 0.153, 0.152, 0.151, 0.150, 0.149, 0.148, 0.147, 0.146, 0.145, 0.144, 0.143, 0.142, 0.141, 0.140, 0.139, 0.138, 0.137, 0.136, 0.135, 0.134, 0.133, 0.133, 0.132, 0.131, 0.130, 0.125, 0.120, etc., or within the range formed by any two of the above values.

[0059] In ultraviolet-visible spectroscopy, absorbance refers to the degree to which light of a specific wavelength is absorbed by a material when it passes through a solution. It is a key optical indicator for quantitatively characterizing the concentration of impurities or chromophores in a solution. Therefore, the extremely low absorbance (at most 0.170) of the concentrated sulfuric acid solution of the polyaryletherketone copolymer at 550 nm directly characterizes the material's extremely high chemical purity and extremely low impurity content. This strictly controlled indicator not only means that the material is clearer and more stable in terms of visual and optical performance, but also reflects the high degree of cleanliness and controllability of its polymerization process, effectively avoiding the formation of byproducts or chromophores such as oxidized structures. This optical purity gives it a competitive advantage in fields with extremely stringent material requirements (such as additive manufacturing).

[0060] As described above, the inventors of this application have discovered that traditional one-pot copolymerization processes are difficult to precisely control the reaction process for phenolic monomers with different reactivity, easily leading to imbalances in the reactivity ratio and side reactions. To address this, the inventors have creatively proposed a core technical solution of stepwise independent salt formation: based on the unique acidity and steric hindrance of each phenolic monomer, it reacts separately with a salt-forming agent under differentiated temperature, time, or medium conditions to form phenolic salt intermediates with well-defined structures and uniform activity. This method enables the control of the activity and feeding sequence of each reaction site, thereby allowing different monomers to grow in a predetermined order and kinetic equilibrium during subsequent copolymerization reactions, effectively suppressing side reactions such as chain-end deactivation or sequence isomerization. The result is that the copolymer fundamentally ensures a high molecular weight, narrow molecular weight distribution, and highly regular chain sequence structure, ultimately achieving the theoretically designed performance of the material and exhibiting excellent batch repeatability.

[0061] A second aspect of this application provides a method for preparing the above-mentioned polyaryletherketone copolymer, the method comprising the following steps: a) Mix the first diphenol monomer in a polar aprotic solvent and heat to form a homogeneous monomer solution; b) Mix the second diphenol monomer in a polar aprotic solvent and heat to form a homogeneous monomer solution; c) In a batch reactor, aromatic difluorine monomers are mixed with a polar aprotic solvent and heated to form a homogeneous monomer solution; d) Mix the salt-forming agent with a polar aprotic solvent; e) The monomer solution obtained in step a) and a portion of the material obtained in step d) undergo a salt formation reaction at 160-180℃ through the first microchannel, with a residence time of 1-20 min; f) The monomer solution obtained in step b) and the remaining material obtained in step d) undergo a salt formation reaction at 180-235℃ through a second microchannel for a residence time of 1-20 min; g) Feed the materials obtained in steps e) and f) into a batch reactor and polycondense at 280-340°C for 1 to 5 hours, preferably 1 to 3 hours, to obtain the polyaryletherketone copolymer.

[0062] Step e) above involves the salt formation process of the first phenol monomer. Specifically, a solution of the first diphenol monomer and a solution of the salt-forming agent are added to the first microchannel; under inert gas protection, the mixture is heated to a first salt-forming temperature T1 (typically 160-180°C) to carry out the salt-forming reaction for a reaction time of t1 (typically 1-20 min), yielding a first phenol salt solution. The first diphenol is preferably a monomer with high reactivity. In some embodiments according to this application, the first diphenol is selected from one or more of hydroquinone, resorcinol, catechol, and 2-methyl-1,4-hydroquinone, preferably hydroquinone.

[0063] Step f) involves the salt formation process of the second phenol monomer. Specifically, a solution of the second diphenol monomer and a salt-forming agent solution are added to the second microchannel; under inert gas protection, the mixture is heated to a second salt-forming temperature T2 (typically 180-235°C) to carry out the salt-forming reaction for a reaction time of t2 (typically 1-20 min), yielding a second phenol salt solution. The second diphenol is preferably a monomer with low reactivity. In some embodiments according to this application, the second diphenol is selected from one or more of 2,2'-dihydroxybiphenyl, 3,3'-dihydroxybiphenyl, 4,4'-dihydroxybiphenyl, 1,4-naphthol, 1,5-naphthol, 2,6-naphthol, and 2,7-naphthol, preferably 4,4'-dihydroxybiphenyl.

[0064] Of course, T1, T2, and t1 and t2 can be optimized and adjusted according to the differences in activity and ratio of the diphenol monomers.

[0065] The stepwise independent salt formation method disclosed in this application has technical advantages and applications that are not limited to binary copolymer systems. The core of this method lies in precise pre-activation and sequence control based on the differences in reactivity of different phenolic monomers; this principle is universally applicable. When the system contains three or more phenolic monomers with different structures and activities, the method of this application remains fully applicable and is particularly crucial.

[0066] To achieve stepwise salt formation and polymerization reactions in the synthesis of polyaryletherketone copolymers, this application provides a tandem reaction system. This system innovatively integrates a microchannel reactor with a batch reactor, solving the technical problems of uneven mixing, low heat transfer efficiency, numerous side reactions, and poor product quality consistency in traditional batch processes.

[0067] In an embodiment according to this application, the tandem reaction system includes a microchannel reactor and a batch reactor, each containing at least two microchannels, connected sequentially. The microchannel reactor is used to continuously and rapidly complete the stepwise salt formation reaction; the batch reactor is connected to the outlet of the microchannel reactor to receive the output material and complete the final polycondensation and molecular weight construction.

[0068] In some embodiments according to this application, the fluid channels of the microchannel reactor have characteristic dimensions between 500 and 1000 micrometers and possess the following structural features and technical parameters: 1) Reactor body: An integrated chip made of high-purity silicon carbide or corrosion-resistant alloy through integral molding or 3D printing technology; the chip surface is anodized and the surface roughness Ra is less than 0.1 micrometers to prevent material from sticking to the wall; 2) Hybrid Enhancement Structure: The reaction channels are multi-stage serpentine or wave-shaped configurations, and contain porous titanium sintered hybrid structures with a porosity of 40% to 60%. This design enables the Reynolds number Re in the reactor to exceed 2000, achieving molecular-level mixing. 3) Heat transfer and temperature control structure: An integrated "reaction / heat exchange" design is adopted, with the reaction channel and heat exchange channel combined. A turbulence diffuser is installed within the heat exchange channel and connected to a high-precision temperature control system; an embedded thermocouple is installed within the reaction channel to achieve a temperature control accuracy of ±0.5℃. The specific surface area of ​​the reaction channel is not less than 15,000 m² / m³. 4) Vacuum devouring interface: The reactor outlet is equipped with a vacuum devouring unit interface, which can be connected to a vacuum system, and the operating vacuum degree is not higher than -0.09MPa.

[0069] 5) System accessories: The reactor feed end is connected to a precision metering pump with a flow error of ±0.5%.

[0070] The reactants are first precisely delivered to the microchannel reactor via a precision metering pump. Within the reactor, the materials undergo efficient mixing and reaction within milliseconds. Thanks to its extremely high heat transfer efficiency and precise temperature control, the salt formation reaction is ensured to proceed at a constant optimal temperature, effectively suppressing side reactions. The generated material, along with any incompletely removed small-molecule byproducts, enters the vacuum devolatilization unit through the outlet, where volatile components are removed under continuous conditions.

[0071] Subsequently, the resulting material enters the batch reactor, where the final molecular chain growth is achieved through nucleophilic substitution.

[0072] This application provides an advanced process solution for the synthesis of high-performance polyaryletherketone copolymers by connecting a microchannel reactor with a batch reactor of the aforementioned specific structure in series. This solution is efficient, precise, and can be mass-produced.

[0073] In some embodiments according to this application, the first salt-forming reaction and the second salt-forming reaction are carried out for 1-20 minutes at a temperature of 170°C to 220°C under an inert atmosphere.

[0074] Therefore, this application achieves a major upgrade and innovation in the process by leveraging the extreme mass and heat transfer capabilities of the microchannel reactor, resulting in significant breakthroughs in reaction efficiency, product quality, and operational stability.

[0075] Step g) involves a polycondensation reaction process. Specifically, a polar aprotic solvent and an aromatic difluoro monomer in approximately the same molar amount as the total diphenol monomers are added to a batch reactor. After heating to a completely molten state, the first and second phenol salt solutions in the microchannel reactor are simultaneously transferred to the batch reactor via a conveying system. Then, under vigorous stirring and an inert atmosphere, the reaction system is gradually heated to the polycondensation temperature T3 (typically 280-340°C). The polycondensation reaction is carried out at this temperature for a time t3 (typically 1-5 hours, preferably 1-3 hours, more preferably 1-2.5 hours).

[0076] After the polycondensation reaction is completed, the resulting viscous material is cooled and pulverized to obtain a crude copolymer. Then, it can be extracted with an organic solvent (such as acetone or ethanol) to remove the solvent and low molecular weight byproducts, followed by washing with deionized water multiple times to remove inorganic salts, and finally dried to obtain a high-purity copolymer.

[0077] In some embodiments of this application, the first diphenol is selected from one or more of hydroquinone, resorcinol, catechol, and 2-methyl-1,4-hydroquinone, preferably hydroquinone; the second diphenol is selected from one or more of 2,2'-dihydroxybiphenyl, 3,3'-dihydroxybiphenyl, 4,4'-dihydroxybiphenyl, 1,4-naphthoquinone, 1,5-naphthoquinone, 2,6-naphthoquinone, and 2,7-naphthoquinone, preferably 4,4'-dihydroxybiphenyl.

[0078] In fact, the stepwise independent salt formation method disclosed in this application has technical advantages and applications not limited to binary copolymer systems. The core of this method lies in precise pre-activation and sequence control based on the differences in reactivity of different phenolic monomers, a principle with universal applicability. When the system contains three or more binary phenolic monomers with different structures and activities, the method of this application remains fully applicable and is particularly crucial.

[0079] In the case of multi-component copolymerization, the method naturally extends to include a corresponding number of independent salt-forming steps, and the microchannel reactor naturally extends to include a corresponding number of microchannels. By optimizing the salt-forming conditions for each phenol monomer to match its chemical properties, the optimal precursor state can be "customized" for each reactant component. This allows for the control of polymerization kinetics in subsequent polycondensation reactions, even when faced with more complex monomer combinations and competitive relationships, ensuring that each monomer participates in chain growth in a predetermined order and proportion.

[0080] Therefore, the method of this application provides an operable and efficient technical route for synthesizing binary, ternary, and even more diverse polyaryletherketone copolymers with well-defined and controllable structures. It significantly broadens the freedom of polymer molecular design, thereby meeting the increasingly complex demands for specialty engineering plastics in high-end fields.

[0081] Typically, the entire reaction process is protected by a continuous flow of inert gas (such as nitrogen) to protect the materials.

[0082] In some embodiments according to this application, the salt-forming agent is an alkali metal carbonate or an alkali metal bicarbonate, preferably selected from one or more of sodium carbonate, potassium carbonate, cesium carbonate, and potassium bicarbonate, more preferably selected from one or more of sodium carbonate and potassium carbonate, and most preferably a mixture of sodium carbonate and potassium carbonate. When the salt-forming agent is a mixture of sodium carbonate and potassium carbonate, the molar ratio of the two is in the range of 60-150:1, preferably in the range of 65-100:1, more preferably in the range of 65-90:1, for example, 60:1, 65:1, 70:1, 72:1, 74:1, 75:1, 76:1, 78:1, 80:1, 82:1, 84:1, 85:1, 87:1, 90:1, 95:1, 100:1, 110:1, 120:1, 130:1, 140:1, 150:1, etc., or within any two of the above values. Compared to single carbonates, this mixed alkali metal carbonate system can optimize the catalytic activity and compatibility of the reaction system through synergistic effects, effectively reduce the activation energy of the reaction, promote the full progress of nucleophilic condensation reaction, reduce the occurrence of side reactions, and improve the molecular weight and structural uniformity of the polymer.

[0083] In some embodiments according to this application, the amount of the salt-forming agent is in excess of 1 mol% to 20 mol% relative to the total molar amount of the diphenols in the system, preferably in excess of 5 mol% to 20 mol%. This excess range represents the balance point between effective salt formation and stable polycondensation. An appropriate excess (e.g., 1-20 mol%) ensures that all phenolic hydroxyl groups are fully converted to phenolate salts and provides the necessary alkaline buffer for the continuous neutralization of byproducts (e.g., hydrogen halides) during subsequent high-temperature polycondensation, thereby driving the reaction towards completion and inhibiting chain termination. Insufficient excess (<1%) may lead to incomplete reaction or a low molecular weight; however, within this preferred range, it ensures reaction kinetics while avoiding side reactions (e.g., hydrolysis or degradation) that may be caused by excessive alkalinity (e.g., excess much higher than 20%), thus providing a quantitative guarantee for achieving high conversion rates and high product quality.

[0084] In some embodiments according to this application, the polar aprotic solvent is selected from one or more of diphenyl sulfone, N-methylpyrrolidone, and N,N-dimethylacetamide, preferably diphenyl sulfone. Preferably, the total weight of the solvent is 2 times or more the weight of the aromatic difluoro monomer, more preferably 2.1 times or more the weight of the aromatic difluoro monomer, more preferably 2.2 times or more the weight of the aromatic difluoro monomer, but not exceeding 10 times. Controlling the solvent weight within the above range ensures that the viscosity of the reaction system is within an appropriate range while avoiding environmental pollution and increased costs caused by excessive solvent.

[0085] In some embodiments according to this application, the aromatic difluoro monomer is 4,4'-difluorobenzophenone or 2,4'-difluorobenzophenone, preferably 4,4'-difluorobenzophenone. The strong electron-withdrawing effect of the fluorine substituent can significantly enhance the electrophilicity of the carbonyl group, promote the efficient nucleophilic substitution reaction with the phenolic hydroxyl group, and the reaction byproduct (fluoride salt) is easily separated from the solvent. The symmetrical structure is more conducive to the formation of regular polymer segments, further ensuring the structural uniformity and performance stability of the material. Therefore, 4,4'-difluorobenzophenone is preferred.

[0086] In some embodiments according to this application, the molar ratio of the total amount of the aromatic difluoro monomer to the diphenol is in the range of 1.001-1.08:1, preferably in the range of 1.003-1.07:1, more preferably in the range of 1.005-1.06:1, and most preferably in the range of 1.005-1.03:1.

[0087] In some embodiments according to this application, the polycondensation reaction is carried out at a temperature of 280°C to 340°C for 1 to 5 hours, preferably at a temperature of 300°C to 330°C for 1 to 3 hours. This temperature range is sufficient to provide the activation energy required to overcome the reaction energy barrier and promote the full progress of the nucleophilic substitution reaction on the aromatic ring, while ensuring that the reaction system is in a molten homogeneous state. The duration within the above range provides the necessary reaction time window for the gradual growth of high molecular weight polymers, achieving an optimal balance between avoiding insufficient polymerization due to too short a time or thermal degradation due to too long a time.

[0088] In some embodiments according to this application, the particle size of the salt-forming agent is ≤400 micrometers. This specific physical specification parameter is one of the key guarantees for achieving long-term, stable, and continuous operation of the subsequent microchannel reactor.

[0089] By limiting the upper limit of the salt-forming agent particle size as described above, it can be ensured that it can smoothly pass through precisely designed microchannels (e.g., channels with characteristic sizes of 500-1000 micrometers) after entering the microchannel reactor, effectively avoiding problems such as microchannel blockage, uneven flow, or local stagnation that may occur due to excessively large particle sizes. The uniformity and fineness of the particle size promote the rapid dispersion and dissolution of the salt-forming agent in the molten medium, thereby ensuring the efficient and uniform conduct of the salt-forming reaction at the molecular scale. This is crucial for obtaining polymers with narrow molecular weight distribution and regular structure.

[0090] Based on this particle size control of the salt-forming agent, combined with the excellent mass and heat transfer capabilities of the microchannel reactor described in this application, the series system can achieve continuous and stable operation for over 300 hours without clogging. This significant technical effect directly translates into a substantial increase in production efficiency and a reduction in production costs, as it greatly reduces downtime caused by equipment cleaning, maintenance, or unplanned shutdowns, ensuring high batch-to-batch consistency of product quality and laying a solid technical foundation for the industrial continuous production of high-performance polyaryletherketone copolymers.

[0091] In summary, these optimized materials, proportions, and process conditions collectively constitute the technical solution for the efficient and controllable synthesis of high-performance polyaryletherketone copolymers presented in this application. Therefore, the preparation method according to this application has the following beneficial effects: Improved reaction efficiency: The extreme mass and heat transfer capacity of the microchannel reactor significantly shortens the salt formation reaction time, realizing a continuous and efficient process. Product quality optimization: Precise material ratio, instantaneous and uniform mixing, and a reaction environment without temperature gradients ensure a narrower molecular weight distribution and more uniform structure of the product, resulting in significantly improved product performance stability and repeatability. Enhanced process control and stability: The entire system achieves continuous and precise control from feeding and reaction to post-processing, eliminating batch differences, improving production automation and operational stability, and is inherently safer due to the small liquid holdup of the system.

[0092] As described above, the method for independent salt formation using a microchannel reactor disclosed in this application has technical advantages and application scope that are not limited to binary copolymer systems. The core of this method lies in precise pre-activation and sequence control based on the differences in reactivity of different phenol monomers, a principle that is universally applicable. When the system contains three or more binary phenol monomers with different structures and activities, the method of this application is still fully applicable. Therefore, the third aspect of this application relates to polyaryletherketone copolymers obtained by the method of this application. In some embodiments of this application, the polyaryletherketone copolymer satisfies one or more of the following (1)-(8): (1) The polyaryletherketone copolymer comprises at least repeating units of Formula I and repeating units of Formula II: O-Ph-O-Ph-CO-Ph Formula I; O-Ph-Ph-O-Ph-CO-Ph Formula II; (2) The polydispersity index (PDI) of the polyaryletherketone copolymer is at most 2.7, preferably at most 2.65, more preferably at most 2.6, and most preferably at most 2.55; (3) The number average molecular weight of the polyaryletherketone copolymer is in the range of 18,000 to 35,000, as determined by GPC. (4) The L value of the polyaryletherketone copolymer is at least 80.0, preferably at least 80.1, and more preferably at least 80.2, as determined by a colorimeter. (5) The b value of the polyaryletherketone copolymer is determined by a colorimeter to be at most 3.60, preferably at most 3.55, more preferably at most 3.45, and most preferably at most 3.40; (6) The initial decomposition temperature of the polyaryletherketone copolymer is determined by thermogravimetric analysis to be at least 566°C, preferably at least 568°C, and more preferably at least 569°C. (7) The gel content of the polyaryletherketone copolymer is determined by filtration method to be at most 0.10%, preferably at most 0.08%, more preferably at most 0.07%, and most preferably at most 0.06%; (8) The absorbance of the concentrated sulfuric acid solution of the polyaryletherketone copolymer at 550 nm is at most 0.170, preferably at most 0.160, and more preferably at most 0.150.

[0093] The fourth aspect of this application provides a printing material, particularly a 3D printing material, comprising a polyaryletherketone copolymer according to the first or third aspect of this application or a polyaryletherketone copolymer prepared by the method according to the second aspect of this application.

[0094] The fifth aspect of this application provides the use of polyaryletherketone copolymers according to the first or third aspect of this application, or polyaryletherketone copolymers prepared by the method according to the second aspect of this application, for the preparation of printing materials, particularly 3D printing materials.

[0095] A sixth aspect of this application provides a prepreg prepared from a polyaryletherketone copolymer according to the first or third aspect of this application, or from a polyaryletherketone copolymer prepared by the method according to the second aspect of this application. In the context of this application, the term "prepreg" refers to a composition of a resin matrix and a reinforcement formed by impregnating a resin matrix with fibers or fabrics continuously used as reinforcement, which is an intermediate material for manufacturing composite materials.

[0096] Example The following embodiments describe the disclosure of this application in more detail. These embodiments are merely illustrative, as various modifications and variations will be apparent to those skilled in the art within the scope of the disclosure of this application. Unless otherwise stated, all parts, percentages, and ratios reported in the following embodiments are based on mass, and all reagents used in the embodiments are commercially available or synthesized by conventional methods and can be used directly without further processing, and the instruments used in the embodiments are commercially available.

[0097] Test method: (1) Molecular weight distribution test: An Agilent Technologies PL-GPC220 HighTemperature Chromatograph was used with α-chloronaphthalene as solvent and 1,2,4-trichlorobenzene as diluent. The column temperature was 125℃, and the mobile phase was a mixture of α-chloronaphthalene and 1,2,4-trichlorobenzene with a mass ratio of α-chloronaphthalene:1,2,4-trichlorobenzene = 1:2.2. The test parameters were K = 14.2 and α = 0.72.

[0098] (2) Colorimetric test: Use a colorimeter to measure the L value, a value, and b value of the sample; (3) The degree of carbonyl branching in polyarylether ketone copolymers can be determined by the following methods: Accurately weigh 1.0 g of polyaryletherketone copolymer and add it to a 100 ml volumetric flask. Add 70 ml (95-98% by weight) of concentrated sulfuric acid to the flask, seal the flask and place it on a shaker for about 30 to 40 hours until dissolved. Add concentrated sulfuric acid to the 100 ml mark and shake the flask to obtain a homogeneous solution. The absorbance of the solution at 550 nm was measured using a UV spectrophotometer. The spectrophotometer was set to absorption mode, with a measurement range of 400 nm to 1000 nm, a data interval of 0.2 nm, a UV / Vis bandwidth of 1.5 nm, a scan rate of 100 nm / min, and a halogen D2 / WI light source.

[0099] (4) Gel content test: The gel content in the copolymer resin was determined using a filtration method. The specific steps are as follows: A. Take a certain mass of polyaryletherketone copolymer resin, keep it at 120℃ for 6 hours until the measured water content is ≤0.1%, take 1.0-1.5g of the above dried resin, accurately weigh it using an analytical balance, and record the mass as M0. Dissolve the weighed resin sample in trichlorotoluene solvent, seal it, and place it on a shaker at 180℃ for 30 hours to dissolve. B. Select a suitable microporous filter membrane that has been treated (soaked in formic acid solution until the mass is constant), with a pore size range of 0.2-0.4 micrometers, and record the mass of the filter membrane as M1; C. Install a sand core filter and a circulating water vacuum pump. During the filtration process, prevent contamination by foreign objects. D. Filter the resin solution. After filtration, rinse with a certain amount of deionized water and anhydrous ethanol. Remove the filter membrane and dry it to constant weight. Its mass is recorded as M2. The gel content in the resin is calculated using the following formula: Gel content = (M2-M1) / M0*100% (5) Thermal stability: Thermogravimetric analysis (TGA) was used to characterize the thermal stability of polyaryletherketone copolymer resin. The initial decomposition temperature determined by TGA was used as the indicator of the thermal stability of the resin because the initial decomposition temperature is the temperature at which the TGA curve begins to deviate from the baseline point and has good repeatability.

[0100] Example 1 Nitrogen gas was continuously introduced into a 3L reactor (raw material melting vessel 1) connected to a water separator, condenser, and stirrer. 490.27g (2.25mol) of diphenyl sulfone and 330.33g (3.0mol) of hydroquinone were added. The mixture was heated to 165℃ to melt the materials and then mixed evenly at a stirring rate of 80r / min. The temperature was maintained at 165℃, and the generated water and gas were separated through a condenser and a separator.

[0101] Nitrogen gas was continuously introduced into a 3L reactor (raw material melting vessel 2) connected to a water separator, condenser, and stirrer. 163.42g (0.75mol) of diphenyl sulfone and 186.21g (1.0mol) of 4,4'-dihydroxybiphenyl were added. The mixture was heated to 165℃ to melt the materials and then mixed evenly at a stirring rate of 80r / min. The temperature was maintained at 165℃, and the generated water and gas were separated through a condenser and a separator.

[0102] Nitrogen gas was continuously introduced into a 3L reactor (raw material melting vessel 3) connected to a water separator, condenser, and stirrer. 742.60g (3.40mol) of diphenyl sulfone, 474.84g (4.48mol) of sodium carbonate and 8.85g (0.064mol) of potassium carbonate were added. The mixture was heated to 160℃ to melt the materials and then mixed evenly at a stirring rate of 80r / min. The temperature was maintained at 160℃, and the generated water and gas were separated through a condenser and a separator.

[0103] Nitrogen gas was continuously introduced into a 5L polymerization reactor (breeding vessel) connected to a water separator, condenser, and agitator. 653.70g (2.99mol) of diphenyl sulfone and 872.80g (4.0mol) of 4,4'-difluorobenzophenone were added. The mixture was heated to 165℃ to melt the materials and then mixed evenly at a stirring rate of 80r / min. The temperature was maintained at 165℃, and the generated water and gas were separated through a condenser and a separator.

[0104] Under nitrogen protection, the materials in raw material melting vessels 1-3 are transported to a microchannel reactor for mixing via a linear flow constant flow pump (metering pump). The materials in raw material melting vessel 1 and part of the materials in raw material melting vessel 3 are kept at 180°C for 10 minutes in microchannel reactor #1 to carry out the salt formation reaction of hydroquinone. At the same time, the materials in raw material melting vessel 2 and the remaining materials in raw material melting vessel 3 are kept at 220°C for 6 minutes in microchannel reactor #2 to carry out the salt formation reaction of 4,4'-dihydroxybiphenyl.

[0105] After the salt formation reaction, the material in the microchannel reactor was transferred to a batch reactor. A stirring rate of 80 r / min was maintained, and the temperature was raised to 310℃ and held at 310℃ for 1-2 hours. When the torque value of the stirrer's torque sensor reached the target value, 10.91 g (0.050 mol) of 4,4'-difluorobenzophenone was added in one go for end-capping. After another 30 minutes, the discharge valve was opened, and the mixture in the batch reactor was quickly poured onto a smooth stainless steel plate for cooling. The cooled material was ground and pulverized (maximum size <2 mm), washed 5-7 times with pure acetone until diphenyl sulfone was no longer detectable in the acetone washing solution, and then washed 5-7 times with deionized water at 68-76℃ until the conductivity of the washing solution was <3 μS / cm. The washed material was then placed in a stainless steel tray and dried in an oven at 150℃ for 8 hours to obtain the PEEK-PEDEK copolymer.

[0106] Example 2 Nitrogen gas was continuously introduced into a 3L reactor (raw material melting vessel 1) connected to a water separator, condenser, and stirrer. 588.33g (2.70mol) of diphenyl sulfone and 405.20g (3.68mol) of hydroquinone were added. The mixture was heated to 160℃ to melt the materials and then mixed evenly at a stirring rate of 80r / min. The temperature was maintained at 160℃, and the generated water and gas were separated through a condenser and a separator.

[0107] Nitrogen gas was continuously introduced into a 3L reactor (raw material melting vessel 2) connected to a water separator, condenser, and stirrer. 65.37g (0.2995mol) of diphenyl sulfone and 76.14g (0.41mol) of 4,4'-dihydroxybiphenyl were added. The mixture was heated to 160℃ to melt the materials and then mixed evenly at a stirring rate of 80r / min. The temperature was maintained at 160℃, and the generated water and gas were separated through a condenser and a separator.

[0108] Nitrogen gas was continuously introduced into a 3L reactor (raw material melting vessel 3) connected to a water separator, condenser, and stirrer. 742.60g (3.40mol) of diphenyl sulfone, 485.39g (4.58mol) of sodium carbonate and 9.04g (0.0654mol) of potassium carbonate were added. The mixture was heated to 160℃ to melt the materials and then mixed evenly at a stirring rate of 80r / min. The temperature was maintained at 160℃, and the generated water and gas were separated through a condenser and a separator.

[0109] Nitrogen gas was continuously introduced into a 5L polymerization reactor (breeding vessel) connected to a water separator, condenser, and agitator. 653.70g (2.99mol) of diphenyl sulfone and 892.19g (4.09mol) of 4,4'-difluorobenzophenone were added. The mixture was heated to 165℃ to melt the materials and then mixed evenly at a stirring rate of 80r / min. The temperature was maintained at 165℃, and the generated water and gas were separated through a condenser and a separator.

[0110] Under nitrogen protection, the materials in raw material melting vessels 1-3 are transported to a microchannel reactor for mixing via a linear flow constant flow pump (metering pump). The materials in raw material melting vessel 1 and part of the materials in raw material melting vessel 3 are kept at 180°C for 12 minutes in microchannel reactor #1 to carry out the salt formation reaction of hydroquinone. At the same time, the materials in raw material melting vessel 2 and the remaining materials in raw material melting vessel 3 are kept at 220°C for 3 minutes in microchannel reactor #2 to carry out the salt formation reaction of 4,4'-dihydroxybiphenyl.

[0111] After the salt formation reaction, the material in the microchannel reactor was transferred to a batch reactor. A stirring rate of 80 r / min was maintained, and the temperature was raised to 310℃ and held at 310℃ for 1-2 hours. When the torque value of the stirrer's torque sensor reached the target value, 10.91 g (0.050 mol) of 4,4'-difluorobenzophenone was added in one go for end-capping. After another 30 minutes, the discharge valve was opened, and the mixture in the batch reactor was quickly poured onto a smooth stainless steel plate for cooling. The cooled material was ground and pulverized (maximum size <2 mm), washed 5-7 times with pure acetone until diphenyl sulfone was no longer detectable in the acetone washing solution, and then washed 5-7 times with deionized water at 68-76℃ until the conductivity of the washing solution was <3 μS / cm. The washed material was then placed in a stainless steel tray and dried in an oven at 150℃ for 8 hours to obtain the PEEK-PEDEK copolymer.

[0112] Example 3 Nitrogen gas was continuously introduced into a 3L reactor (raw material melting vessel 1) connected to a water separator, condenser, and stirrer. 315.69g (1.45mol) of diphenyl sulfone and 220.22g (2.0mol) of hydroquinone were added. The mixture was heated to 165℃ to melt the materials and then mixed evenly at a stirring rate of 80r / min. The temperature was maintained at 165℃, and the generated water and gas were separated through a condenser and a separator.

[0113] Nitrogen gas was continuously introduced into a 3L reactor (raw material melting vessel 2) connected to a water separator, condenser, and stirrer. 315.69g (1.45mol) of diphenyl sulfone and 372.42g (2.0mol) of 4,4'-dihydroxybiphenyl were added. The mixture was heated to 175℃ to melt the materials and then mixed evenly at a stirring rate of 80r / min. The temperature was maintained at 175℃, and the generated water and gas were separated through a condenser and a separator.

[0114] Nitrogen gas was continuously introduced into a 3L reactor (raw material melting vessel 3) connected to a water separator, condenser, and stirrer. 717.24g (3.29mol) of diphenyl sulfone, 474.83g (4.48mol) of sodium carbonate and 8.85g (0.064mol) of potassium carbonate were added. The mixture was heated to 170℃ to melt the materials and then mixed evenly at a stirring rate of 80r / min. The temperature was maintained at 170℃, and the generated water and gas were separated through a condenser and a separator.

[0115] Nitrogen gas was continuously introduced into a 5L polymerization reactor (breeding vessel) connected to a water separator, condenser, and agitator. 631.38g (2.89mol) of diphenyl sulfone and 872.80g (4.0mol) of 4,4'-difluorobenzophenone were added. The mixture was heated to 170℃ to melt the materials and then mixed evenly at a stirring rate of 80r / min. The temperature was maintained at 170℃, and the generated water and gas were separated through a condenser and a separator.

[0116] Under nitrogen protection, the materials in raw material melting vessels 1-3 are transported to a microchannel reactor for mixing via a linear flow constant flow pump (metering pump). The materials in raw material melting vessel 1 and part of the materials in raw material melting vessel 3 are kept at 180°C for 8 minutes in microchannel reactor #1 to carry out the salt formation reaction of hydroquinone. At the same time, the materials in raw material melting vessel 2 and the remaining materials in raw material melting vessel 3 are kept at 220°C for 8 minutes in microchannel reactor #2 to carry out the salt formation reaction of 4,4'-dihydroxybiphenyl.

[0117] After the salt formation reaction, the material in the microchannel reactor was transferred to a batch reactor. A stirring rate of 80 r / min was maintained, and the temperature was raised to 310℃. This temperature was held constant for 1-2 hours. When the torque sensor of the stirrer reached the target value, 10.91 g (0.050 mol) of 4,4'-difluorobenzophenone was added in one go for end-capping. After another 30 minutes, the discharge valve was opened, and the mixture in the batch reactor was quickly poured onto a smooth stainless steel plate for cooling. The cooled material was then ground (maximum size <2 mm), washed 5-7 times with pure acetone until diphenyl sulfone was no longer detectable in the acetone wash, and then washed 5-7 times with deionized water at 68-76℃ until the conductivity of the wash solution was <3 μS / cm. The washed material was then placed in a stainless steel tray and dried in an oven at 150℃ for 8 hours to obtain the PEEK-PEDEK copolymer.

[0118] Comparative Example 1 Nitrogen gas was continuously introduced into a 15L reactor (breeding vessel) connected to a water separator, condenser, and stirrer. 2050.0g (9.39mol) diphenyl sulfone, 872.80g (4.0mol) 4,4-difluorobenzophenone, 330.33g (3.0mol) hydroquinone, 186.21g (1.0mol) 4,4'-dihydroxybiphenyl, 474.84g (4.48mol) sodium carbonate, and 8.85g (0.064mol) potassium carbonate were added. The mixture was heated to 180℃ to melt the materials, then stirred at 80r / min until homogeneous. The temperature was maintained at 180℃ for 2 hours, then increased to 220℃ and maintained for 2.5 hours. The generated water and gas were condensed by the condenser and separated by the water separator.

[0119] Maintain a stirring rate of 80 r / min, raise the temperature to 310℃, and hold at 310℃ for 1-2 hours. When the torque value of the stirrer's torque sensor reaches the target value, add 10.91 g (0.050 mol) of 4,4'-difluorobenzophenone for end-capping treatment. After another 30 minutes, open the discharge valve and quickly pour the mixture in the batch reactor onto a smooth stainless steel plate for cooling. Grind the cooled material (maximum size <2 mm), wash it 5-7 times with pure acetone until diphenyl sulfone is no longer detected in the acetone washing solution, wash it 5-7 times with deionized water at 68-76℃ until the conductivity of the washing solution is <3 μS / cm, and place the washed material into a stainless steel tray and dry it in an oven at 150℃ for 8 hours to obtain the PEEK-PEDEK copolymer.

[0120] Comparative Example 2 Nitrogen gas was continuously introduced into a 5L reactor (breeding vessel) connected to a water separator, condenser, and stirrer. 2050.0g (9.39mol) of diphenyl sulfone, 892.19g (4.09mol) of 4,4'-difluorobenzophenone, 405.20g (3.68mol) of hydroquinone, 76.13g (0.4089mol) of 4,4'-dihydroxybiphenyl, 485.39g (4.58mol) of sodium carbonate, and 9.04g (0.0654mol) of potassium carbonate were added. The mixture was heated to 180℃ to melt the materials, and then stirred at 80r / min until homogeneous. The temperature was maintained at 180℃ for 2 hours, then increased to 220℃ and maintained at 220℃ for 2.5 hours. The generated water and gas were separated through a condenser and a separator.

[0121] Maintain a stirring rate of 80 r / min, raise the temperature to 310℃, and hold at 310℃ for 1-2 hours. When the torque value of the stirrer's torque sensor reaches the target value, add 10.91 g (0.050 mol) of 4,4'-difluorobenzophenone for end-capping treatment. After another 30 minutes, open the discharge valve and quickly pour the mixture in the batch reactor onto a smooth stainless steel plate for cooling. Grind the cooled material (maximum size <2 mm), wash with pure acetone 5-7 times until diphenyl sulfone is no longer detected in the acetone washing solution, and wash with deionized water at 68-76℃ 5-7 times until the conductivity of the washing solution is <3 μS / cm. Place the washed material into a stainless steel tray and dry in an oven at 150℃ for 8 hours to obtain the PEEK-PEDEK copolymer.

[0122] Comparative Example 3 Nitrogen gas was continuously introduced into a 5L reactor (breeding vessel) connected to a water separator, condenser, and stirrer. 1980.0g (9.07mol) of diphenyl sulfone, 872.80g (4.0mol) of 4,4'-difluorobenzophenone, 220.22g (2.0mol) of hydroquinone, 372.42g (2.0mol) of 4,4'-dihydroxybiphenyl, 474.83g (4.48mol) of sodium carbonate, and 8.85g (0.064mol) of potassium carbonate were added. The mixture was heated to 180℃ to melt the materials, and then stirred at 80r / min until homogeneous. The temperature was maintained at 180℃ for 2 hours, then increased to 220℃ and maintained at 220℃ for 2.5 hours. The generated water and gas were separated by a condenser and a separator.

[0123] Maintain a stirring rate of 80 r / min, raise the temperature to 310℃, and hold at 310℃ for 1-2 hours. When the torque value of the stirrer's torque sensor reaches the target value, add 10.91 g (0.050 mol) of 4,4'-difluorobenzophenone for end-capping treatment. After another 30 minutes, open the discharge valve and quickly pour the mixture in the batch reactor onto a smooth stainless steel plate for cooling. Grind the cooled material (maximum size <2 mm), wash with pure acetone 5-7 times until diphenyl sulfone is no longer detected in the acetone washing solution, and wash with deionized water at 68-76℃ 5-7 times until the conductivity of the washing solution is <3 μS / cm. Place the washed material into a stainless steel tray and dry in an oven at 150℃ for 8 hours to obtain the PEEK-PEDEK copolymer.

[0124] The torque values ​​in the above embodiments and comparative examples may be the same or different. Those skilled in the art can make reasonable selections based on specific experimental equipment, experimental conditions, and conventional operating experience.

[0125] The copolymers of the examples and comparative examples were tested according to the above test methods, and the results are shown in Tables 1 to 5 below.

[0126] Table 1. Color test results of polyaryletherketone copolymers

[0127] According to the color test results in Table 1, there are significant differences in the L and b values ​​between the example samples and the comparative samples in terms of color parameters. Specifically, the L value of the example samples is significantly higher, indicating better brightness and a lighter color; while the b value of the comparative samples is significantly higher, indicating a more yellowish color. Overall, the comparative samples are darker and more yellowish, which is likely related to their lower thermal stability and greater susceptibility to oxidative degradation.

[0128] Table 2. TGA test results of polyaryletherketone copolymers

[0129] According to the test results in Table 2, the polyaryletherketone copolymers prepared in the embodiments of this application are superior to the polyaryletherketone copolymers prepared in the comparative examples in terms of thermal stability.

[0130] Table 3. Molecular weight distribution of polyaryletherketone copolymers

[0131] According to the test results in Table 3, the PDI value of the polyaryletherketone copolymer prepared in the embodiments of this application is significantly lower than that of the comparative sample, indicating that the polyaryletherketone copolymer of the embodiments has a narrower molecular weight distribution.

[0132] Table 4. Test results of gel content of polyaryletherketone copolymer resin

[0133] According to the test results in Table 4, the gel content of the polyaryletherketone copolymer prepared in the embodiments of this application is significantly lower than that of the polyaryletherketone copolymer in the comparative example, indicating that the polyaryletherketone copolymer in the embodiments exhibits higher purity.

[0134] Table 5. Branching degree test results of polyaryletherketone copolymers

[0135] As shown in Table 5, the absorbance of the concentrated sulfuric acid solution of the polyaryletherketone copolymer according to the embodiments of this application is significantly lower than that of the comparative example at 550 nm. The lower absorbance directly reflects the low degree of branching of the polymer chains and the high structural regularity, indicating that it has superior intrinsic quality.

[0136] Table 6. Comparison of the method according to this application with the traditional one-pot method

[0137] As can be seen from the table above, the method of this application has achieved a major breakthrough in reaction efficiency and product quality.

[0138] Some exemplary implementations are described below: Implementation Method 1. A polyaryletherketone copolymer, which is basically composed of repeating units of Formula I and repeating units of Formula II: O-Ph-O-Ph-CO-Ph Formula I O-Ph-Ph-O-Ph-CO-Ph Formula II Wherein, the molar ratio of the repeating unit of Formula I to the repeating unit of Formula II is 50:50 to 95:5, preferably 60:40 to 90:10, more preferably 70:30 to 85:15; and The polydispersity index (PDI) of the polyaryletherketone copolymer is at most 2.7, preferably at most 2.65, more preferably at most 2.6, and most preferably at most 2.55.

[0139] Embodiment 2. The polyaryletherketone copolymer according to Embodiment 1, wherein the number-average molecular weight of the polyaryletherketone copolymer is in the range of 18,000 to 35,000 as determined by GPC.

[0140] Embodiment 3. The polyaryletherketone copolymer according to Embodiment 1 or 2, wherein the L value of the polyaryletherketone copolymer, as determined by a colorimeter, is at least 80.0, preferably at least 80.1, and more preferably at least 80.2.

[0141] Embodiment 4. The polyaryletherketone copolymer according to any one of Embodiments 1 to 3, wherein, as determined by a colorimeter, the b-value of the polyaryletherketone copolymer is at most 3.60, preferably at most 3.55, more preferably at most 3.45, and most preferably at most 3.40.

[0142] Embodiment 5. The polyaryletherketone copolymer according to any one of Embodiments 1 to 4, wherein the initial decomposition temperature of the polyaryletherketone copolymer, as determined by thermogravimetric analysis, is at least 566°C, preferably at least 568°C, and more preferably at least 569°C.

[0143] Embodiment 6. The polyaryletherketone copolymer according to any one of Embodiments 1 to 5, wherein, as determined by filtration, the gel content of the polyaryletherketone copolymer is at most 0.10%, preferably at most 0.08%, more preferably at most 0.07%, and most preferably at most 0.06%.

[0144] Embodiment 7. The polyaryletherketone copolymer according to any one of Embodiments 1 to 6, wherein the absorbance of the concentrated sulfuric acid solution of the polyaryletherketone copolymer is at most 0.170, preferably at most 0.160, and more preferably at most 0.150.

[0145] Embodiment 8. A method for preparing the polyaryletherketone copolymer according to any one of Embodiments 1 to 7, comprising the following steps: a) Mix the first diphenol monomer in a polar aprotic solvent and heat to form a homogeneous monomer solution; b) Mix the second diphenol monomer in a polar aprotic solvent and heat to form a homogeneous monomer solution; c) In a batch reactor, aromatic difluorine monomers are mixed with a polar aprotic solvent and heated to form a homogeneous monomer solution; d) Mix the salt-forming agent with a polar aprotic solvent; e) The monomer solution obtained in step a) and a portion of the material obtained in step d) undergo a salt formation reaction at 160-180℃ through the first microchannel, with a residence time of 1-20 min; f) The monomer solution obtained in step b) and the remaining material obtained in step d) undergo a salt formation reaction at 180-235℃ through a second microchannel for a residence time of 1-20 min; g) Feed the materials obtained in steps e) and f) into a batch reactor and polycondense them at 280-340°C for 1 to 5 hours to obtain the polyaryletherketone copolymer.

[0146] Implementation 9. The method according to Implementation 8, wherein the method is carried out in a series system of a batch reactor and a microchannel reactor containing at least two microchannels.

[0147] Embodiment 10. The method according to Embodiment 8 or 9, wherein the first diphenol is selected from one or more of hydroquinone, resorcinol, catechol and 2-methyl-1,4-hydroquinone, preferably hydroquinone; the second diphenol is selected from one or more of 2,2'-dihydroxybiphenyl, 3,3'-dihydroxybiphenyl, 4,4'-dihydroxybiphenyl, 1,4-naphthoquinone, 1,5-naphthoquinone, 2,6-naphthoquinone and 2,7-naphthoquinone, preferably 4,4'-dihydroxybiphenyl.

[0148] Embodiment 11. The method according to any one of Embodiments 8 to 10, wherein the salt-forming agent is an alkali metal carbonate or an alkali metal bicarbonate, preferably selected from one or more of potassium carbonate, sodium carbonate, cesium carbonate and potassium bicarbonate, and more preferably selected from one or more of potassium carbonate and sodium carbonate.

[0149] Implementation Method 12. The method according to any one of Implementation Methods 8 to 11, wherein the amount of the salt-forming agent is in excess of 1 mol% to 20 mol% relative to the total molar amount of the diphenols in the system, preferably in excess of 5 mol% to 20 mol%.

[0150] Embodiment 13. The method according to any one of Embodiments 8 to 12, wherein the polar aprotic solvent is selected from one or more of diphenyl sulfone, N-methylpyrrolidone and N,N-dimethylacetamide, preferably diphenyl sulfone.

[0151] Embodiment 14. The method according to any one of Embodiments 8 to 13, wherein the aromatic difluoro monomer is 4,4'-difluorobenzophenone or 2,4'-difluorobenzophenone, preferably 4,4'-difluorobenzophenone.

[0152] Implementation Method 15. The method according to any one of Implementation Methods 8 to 14, wherein the particle size of the salt-forming agent is ≤400 micrometers.

[0153] Embodiment 16. A polyaryletherketone copolymer obtained by the method according to any one of Embodiments 8 to 15.

[0154] Embodiment 17. The polyaryletherketone copolymer according to Embodiment 16, wherein the polyaryletherketone copolymer satisfies one or more of the following (1)-(8): (1) The polyaryletherketone copolymer comprises at least repeating units of Formula I and repeating units of Formula II: O-Ph-O-Ph-CO-Ph Formula I; O-Ph-Ph-O-Ph-CO-Ph Formula II; (2) The polydispersity index (PDI) of the polyaryletherketone copolymer is at most 2.7, preferably at most 2.65, more preferably at most 2.6, and most preferably at most 2.55; (3) The number average molecular weight of the polyaryletherketone copolymer is in the range of 18,000 to 35,000, as determined by GPC. (4) The L value of the polyaryletherketone copolymer is at least 80.0, preferably at least 80.1, and more preferably at least 80.2, as determined by a colorimeter. (5) The b value of the polyaryletherketone copolymer is determined by a colorimeter to be at most 3.60, preferably at most 3.55, more preferably at most 3.45, and most preferably at most 3.40; (6) The initial decomposition temperature of the polyaryletherketone copolymer is determined by thermogravimetric analysis to be at least 566°C, preferably at least 568°C, and more preferably at least 569°C. (7) The gel content of the polyaryletherketone copolymer is determined by filtration method to be at most 0.10%, preferably at most 0.08%, more preferably at most 0.07%, and most preferably at most 0.06%; (8) The absorbance of the concentrated sulfuric acid solution of the polyaryletherketone copolymer at 550 nm is at most 0.170, preferably at most 0.160, and more preferably at most 0.150.

[0155] Embodiment 18. A printing material, particularly a 3D printing material, comprising any one of Embodiments 1 to 7 or the polyaryletherketone copolymer described in Embodiments 16 or 17 or the polyaryletherketone copolymer prepared by the method described in any one of Embodiments 8 to 15.

[0156] Example 19. Use of the polyaryletherketone copolymer of any one of Examples 1 to 7 or the polyaryletherketone copolymer of Example 16 or 17 or the polyaryletherketone copolymer prepared by the method of any one of Examples 8 to 15 for the preparation of printing materials, particularly 3D printing materials.

[0157] Embodiment 20. A prepreg prepared from any one of Embodiments 1 to 7 or the polyaryletherketone copolymer described in Embodiments 16 or 17, or the polyaryletherketone copolymer prepared by the method described in any one of Embodiments 8 to 15.

[0158] Although this application has been described with reference to numerous embodiments and examples, those skilled in the art will recognize from the disclosure of this application that other embodiments can be designed without departing from the protection scope of this application.

Claims

1. A polyaryletherketone copolymer, which is basically composed of repeating units of Formula I and repeating units of Formula II: O-Ph-O-Ph-CO-Ph Formula I O-Ph-Ph-O-Ph-CO-Ph Formula II Wherein, the molar ratio of the repeating unit of Formula I to the repeating unit of Formula II is 50:50 to 95:5, preferably 60:40 to 90:10, more preferably 70:30 to 85:15; and The polydispersity index (PDI) of the polyaryletherketone copolymer is at most 2.7, preferably at most 2.65, more preferably at most 2.6, and most preferably at most 2.

55.

2. The polyaryletherketone copolymer according to claim 1, wherein, The number-average molecular weight of the polyaryletherketone copolymer, as determined by GPC, is in the range of 18,000 to 35,000.

3. The polyaryletherketone copolymer according to claim 1 or 2, wherein, The L value of the polyaryletherketone copolymer, as determined by a colorimeter, is at least 80.0, preferably at least 80.1, and more preferably at least 80.

2.

4. The polyaryletherketone copolymer according to any one of claims 1 to 3, wherein, The b-value of the polyaryletherketone copolymer, as determined by a colorimeter, is at most 3.60, preferably at most 3.55, more preferably at most 3.45, and most preferably at most 3.

40.

5. The polyaryletherketone copolymer according to any one of claims 1 to 4, wherein, The initial decomposition temperature of the polyaryletherketone copolymer, as determined by thermogravimetric analysis, is at least 566°C, preferably at least 568°C, and more preferably at least 569°C.

6. The polyaryletherketone copolymer according to any one of claims 1 to 5, wherein, The gel content of the polyaryletherketone copolymer, as determined by filtration, is at most 0.10%, preferably at most 0.08%, more preferably at most 0.07%, and most preferably at most 0.06%.

7. The polyaryletherketone copolymer according to any one of claims 1 to 6, wherein, The absorbance of the concentrated sulfuric acid solution of the polyaryletherketone copolymer at 550 nm is at most 0.170, preferably at most 0.160, and more preferably at most 0.

150.

8. A method for preparing the polyaryletherketone copolymer according to any one of claims 1 to 7, comprising the following steps: a) Mix the first diphenol monomer in a polar aprotic solvent and heat to form a homogeneous monomer solution; b) Mix the second diphenol monomer in a polar aprotic solvent and heat to form a homogeneous monomer solution; c) In a batch reactor, aromatic difluorine monomers are mixed with a polar aprotic solvent and heated to form a homogeneous monomer solution; d) Mix the salt-forming agent with a polar aprotic solvent; e) The monomer solution obtained in step a) and a portion of the material obtained in step d) undergo a salt formation reaction at 160-180℃ through the first microchannel, with a residence time of 1-20 min; f) The monomer solution obtained in step b) and the remaining material obtained in step d) undergo a salt formation reaction at 180-235℃ through a second microchannel for a residence time of 1-20 min; g) Feed the materials obtained in steps e) and f) into a batch reactor and polycondense them at 280-340°C for 1 to 5 hours to obtain the polyaryletherketone copolymer.

9. The method according to claim 8, wherein, The method is carried out in a series system of a batch reactor and a microchannel reactor containing at least two microchannels.

10. The method according to claim 8 or 9, wherein, The first diphenol is selected from one or more of hydroquinone, resorcinol, catechol and 2-methyl-1,4-hydroquinone, preferably hydroquinone; the second diphenol is selected from one or more of 2,2'-dihydroxybiphenyl, 3,3'-dihydroxybiphenyl, 4,4'-dihydroxybiphenyl, 1,4-naphthoquinone, 1,5-naphthoquinone, 2,6-naphthoquinone and 2,7-naphthoquinone, preferably 4,4'-dihydroxybiphenyl.

11. The method according to any one of claims 8 to 10, wherein, The salt-forming agent is an alkali metal carbonate or an alkali metal bicarbonate, preferably selected from one or more of potassium carbonate, sodium carbonate, cesium carbonate and potassium bicarbonate, and more preferably selected from one or more of potassium carbonate and sodium carbonate.

12. The method according to any one of claims 8 to 11, wherein, The amount of the salt-forming agent used is 1 mol% to 20 mol excess relative to the total molar amount of diphenols in the system, preferably 5 mol% to 20 mol excess.

13. The method according to any one of claims 8 to 12, wherein, The polar aprotic solvent is selected from one or more of diphenyl sulfone, N-methylpyrrolidone and N,N-dimethylacetamide, preferably diphenyl sulfone.

14. The method according to any one of claims 8 to 13, wherein, The aromatic difluoro monomer is 4,4'-difluorobenzophenone or 2,4'-difluorobenzophenone, preferably 4,4'-difluorobenzophenone.

15. The method according to any one of claims 8 to 14, wherein, The particle size of the salt-forming agent is ≤400 micrometers.

16. A polyaryletherketone copolymer obtained by the method according to any one of claims 8 to 15.

17. The polyaryletherketone copolymer according to claim 16, wherein, The polyaryletherketone copolymer satisfies one or more of the following (1)-(8): (1) The polyaryletherketone copolymer comprises at least repeating units of Formula I and repeating units of Formula II: O-Ph-O-Ph-CO-Ph Formula I; O-Ph-Ph-O-Ph-CO-Ph Formula II; (2) The polydispersity index (PDI) of the polyaryletherketone copolymer is at most 2.7, preferably at most 2.65, more preferably at most 2.6, and most preferably at most 2.55; (3) The number average molecular weight of the polyaryletherketone copolymer is in the range of 18,000 to 35,000, as determined by GPC. (4) The L value of the polyaryletherketone copolymer is at least 80.0, preferably at least 80.1, and more preferably at least 80.2, as determined by a colorimeter. (5) The b value of the polyaryletherketone copolymer is determined by a colorimeter to be at most 3.60, preferably at most 3.55, more preferably at most 3.45, and most preferably at most 3.40; (6) The initial decomposition temperature of the polyaryletherketone copolymer is determined by thermogravimetric analysis to be at least 566°C, preferably at least 568°C, and more preferably at least 569°C. (7) The gel content of the polyaryletherketone copolymer is determined by filtration method to be at most 0.10%, preferably at most 0.08%, more preferably at most 0.07%, and most preferably at most 0.06%; (8) The absorbance of the concentrated sulfuric acid solution of the polyaryletherketone copolymer at 550 nm is at most 0.170, preferably at most 0.160, and more preferably at most 0.

150.

18. A printing material comprising any one of claims 1 to 7 or the polyaryletherketone copolymer of claims 16 or 17 or the polyaryletherketone copolymer prepared by the method of any one of claims 8 to 15, particularly a 3D printing material.

19. Use of the polyaryletherketone copolymer of any one of claims 1 to 7 or the polyaryletherketone copolymer of claims 16 or 17 or the polyaryletherketone copolymer prepared by the method of any one of claims 8 to 15 for the preparation of printing materials, particularly 3D printing materials.

20. A prepreg prepared from any one of claims 1 to 7 or the polyaryletherketone copolymer of claims 16 or 17 or the polyaryletherketone copolymer prepared by the method of any one of claims 8 to 15.

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