Polyether ether ketone composite and method of forming

Abstract

The application discloses a polyether ether ketone composite material and a forming method, and belongs to the technical field of new materials; the polyether ether ketone composite material is prepared from raw materials of modified hexagonal boron nitride and PEEK powder; the hexagonal boron nitride hBN-PEEK with a surface grafted PEEK is prepared through fused deposition 3D printing, and the structure of the hexagonal boron nitride hBN-PEEK is oriented along the X-Y direction; and the hBN-PEEK with a liquid crystal structure is formed through heat treatment. The FDM process is used to form a highly oriented and closely packed liquid crystal structure; the polar group and the dipole in the liquid crystal polymer are limited in the movement perpendicular to the orientation direction, the polarization movement rate is effectively slowed down, the work done by the intermolecular friction in a unit time is reduced, and thus the dielectric loss of the liquid crystal PEEK at a high frequency is reduced.

Description

Technical Field

[0001] This invention belongs to the field of new materials technology, specifically relating to a polyether ether ketone composite material and its molding method. Background Technology

[0002] PEEK (polyetheretherketone) materials possess properties such as low density, corrosion resistance, dimensional stability, good wave transmission, and resistance to mold and salt spray, enabling guidance equipment to operate normally in extreme environments without interference to transmitted and received signals. However, with the continuous increase in information transmission power, high-frequency communication millimeter waves (26.5–300 GHz) cause a significant increase in the heat flux density of chips, leading to a rapid increase in heat generation. Excessive heat accumulation can easily cause electronic components or equipment to burn out or age, reducing the reliability of material operation and shortening its lifespan. Furthermore, the wave transmission performance of conventional PEEK is no longer sufficient to meet the application requirements. Therefore, it is necessary to further reduce the dielectric constant and loss of PEEK materials to reduce their electromagnetic wave loss, while simultaneously improving the thermal conductivity of the material to meet the heat dissipation requirements of high-frequency, high-speed communication.

[0003] Currently, common solutions include molecular structure design and blending modification. Molecular structure design reduces the dielectric constant by introducing structures such as large fluorine-containing side groups or rigid naphthalene ring chains to decrease crystallinity or introduce large free volumes. Blending modification, on the other hand, introduces voids by adding fillers such as hollow glass microspheres to reduce the dielectric constant. It is evident that existing solutions all aim to reduce the dielectric constant by introducing low-dielectric functional groups or voids. However, this approach typically leads to deterioration of mechanical properties and increases losses from electromagnetic field polarization of functional groups, making it difficult to meet the requirements of low loss and high thermal conductivity in high-power electromagnetic wave transmission. Summary of the Invention

[0004] The purpose of this invention is to provide a polyetheretherketone composite material and a molding method to solve the problem that conventional PEEK materials cannot meet the requirements of low loss and high thermal conductivity.

[0005] This invention is achieved through the following technical solution:

[0006] The polyetheretherketone (PEEK) composite material is prepared from raw materials made of modified hexagonal boron nitride and PEEK powder. The hexagonal boron nitride (hBN-PEEK) grafted with PEEK is prepared by fused deposition modeling (FDM) to obtain a structure in which all the hexagonal boron nitride (hBN-PEEK) grafted with PEEK is oriented along the XY direction. The hBN-PEEK is then heat-treated to form a liquid crystal-like structure.

[0007] In some embodiments of the present invention, the modified hexagonal boron nitride is hexagonal boron nitride hBN-PEEK with PEEK grafted on the surface.

[0008] On the other hand, the present invention also provides a method for molding polyetheretherketone composite materials, comprising the following steps:

[0009] S01. Hexagonal boron nitride is modified to obtain hexagonal boron nitride hBN-PEEK with PEEK grafted on the surface.

[0010] S02. A printing filament suitable for FDM was prepared using modified hexagonal boron nitride (hBN-PEEK), PEEK powder, and a plasticizer.

[0011] S03. Using the prepared printing filament, printing was started along the X-0° direction according to the digital model to prepare a structure in which hBN-PEEK is oriented along the XY direction;

[0012] S04. The obtained hBN-PEEK structure, which is oriented along the XY direction, is subjected to heat treatment to allow the incompletely crystallized molecular chains to recrystallize and form a liquid crystal-like structure of hBN-PEEK.

[0013] In some embodiments of the present invention, the step of modifying hexagonal boron nitride includes:

[0014] S011. Hexagonal boron nitride (hBN) is hydroxylated to obtain modified boron nitride hBN-OH with hydroxyl functional groups on its surface.

[0015] S012. By esterification of carboxyl and hydroxyl groups, hBN-OH is converted into boron nitride hBN-COOH with carboxyl-terminal groups modified.

[0016] S013. Soluble polyether ether ketone molecular chains with protected carbonyl groups are grafted onto the surface of hBN-COOH via esterification of carboxyl groups.

[0017] S014. The grafted soluble polyether ether ketone is converted into polyether ether ketone with high crystallinity through a deprotection reaction, thereby obtaining hexagonal boron nitride hBN-PEEK with PEEK grafted on the surface.

[0018] In some embodiments of the present invention, in step S011, hydroxylation is performed using a sodium hydroxide chemical reaction method, with a sodium hydroxide solution concentration of 5 mol / mL, a reaction temperature of 100 °C, and a reaction time of 6-24 hours.

[0019] In some embodiments of the present invention, in step S013, a soluble polyether ether ketone molecular chain with a carbonyl protected grafted onto a polyether ether ketone-1,3-dithiopentane is used, and the hydroxyl content of the polyether ether ketone-1,3-dithiopentane is 5%-10%.

[0020] In some embodiments of the present invention, in step S02, the hBN-PEEK content used in preparing the printing filament is 1wt% to 40wt%.

[0021] In some embodiments of the present invention, in step S03, during the fused deposition modeling 3D printing operation, the obtained hBN-PEEK structure, which is oriented along the XY direction, is subjected to a rolling operation by a rolling device.

[0022] In some embodiments of the present invention, in step S04, the heat treatment temperature is 200℃-300℃, the heat treatment time is 1-10 hours, and the cooling rate after heat treatment is 0.1℃ / min-10℃ / min.

[0023] On the other hand, the present invention also provides a polyetheretherketone composite material prepared by the aforementioned polyetheretherketone composite material molding method.

[0024] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0025] This invention uses FDM process to form a highly oriented and closely packed liquid crystal-like structure. The movement of polar groups and dipoles in the liquid crystal-like polymer perpendicular to the orientation direction is restricted, and the polarization rate is effectively slowed down, reducing the work done by intermolecular friction per unit time (friction work), thereby reducing the dielectric loss of liquid crystal-like PEEK at high frequencies.

[0026] By combining the FDM molding process with horizontally oriented hBN grafted with PEEK along the printing direction, an orderly arrangement structure resembling a "mussel" can be formed, thereby more effectively utilizing the thermal conductivity and impact resistance of boron nitride.

[0027] This invention uses FDM printing, which allows for flexible structural design and optimization, high material utilization, and fewer post-processing steps. This can shorten the design and manufacturing cycle, reduce production costs, and allow for the design of various complex structures according to requirements, thereby achieving flexible and efficient customization of target components. Attached Figure Description

[0028] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a flowchart illustrating the molding process of polyetheretherketone composite materials according to an embodiment of the present invention.

[0030] Figure 2This is a schematic diagram of the modification treatment of hexagonal boron nitride according to an embodiment of the present invention.

[0031] Figure 3 The chemical structural formula of hBN-PEEK.

[0032] Figure 4 The chemical structural formula of hBN-PEEKDith.

[0033] Figure 5 This is a schematic diagram of the structure prepared by fused deposition modeling in an embodiment of the present invention.

[0034] Figure 6 A schematic diagram showing the structure of an embodiment of the present invention with the addition of a rolling process.

[0035] Figure 7 This is a schematic diagram showing the crystal strand configurations formed by unmodified and modified liquid crystal arrangements.

[0036] Figure 8 This is a schematic diagram showing the dielectric loss of a liquid crystal-like structure and a conventional structure at high frequencies. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments.

[0038] Hexagonal boron nitride (hBN) possesses excellent physicochemical properties and high mechanical properties due to its unique crystal structure. Its in-plane mechanical strength can reach 500 N / m, and it exhibits outstanding high-temperature resistance, with an oxidation resistance temperature of 800–900℃ in air and reaching 2000℃ under vacuum conditions. It also has extremely high thermal conductivity. The theoretically calculated thermal conductivity of hexagonal boron nitride nanosheets (BNNSs) is as high as 1700–2000 W / (m·K). More importantly, hBN possesses excellent insulating properties, with a bandgap of 5.0–6.0 eV, a breakdown strength as high as 35 kV / mm, a dielectric constant of approximately 3.5, and a dielectric loss of 2.5 × 10⁻⁶. -4 This allows hBN to be used in the field of functional composite materials where both insulation and heat dissipation are required.

[0039] However, how to uniformly disperse hBN in PEEK to improve the dielectric and thermal conductivity of PEEK remains an urgent problem to be solved.

[0040] Research has found that the main reason is that PEEK's excellent chemical stability is a "double-edged sword." Although it enables PEEK to be used in a variety of extreme environments, it inevitably brings the problem of not being able to form chemical bonds with the filler surface. This is one of the two major factors contributing to the poor interfacial performance of PEEK composites.

[0041] Dynamic molecular simulation studies have revealed:

[0042] Polymers physically adsorbed onto rigid surfaces (especially those with highly rigid molecular chains) tend to be distributed in an extended manner within a monolayer of molecules on the filler surface. In this case, the polymer not only cannot nucleate in a folded manner, but the mobility of the molecular chains (the ability to fit into the crystal lattice) is also significantly reduced. When the polymer is chemically bonded to the filler surface, the polymer molecular chains not only tend to align perpendicular to the grafted surface, but the entropy penalty for nucleation is also reduced, thereby improving the crystallinity of the interfacial polymer.

[0043] Therefore, modifying the hBN surface by grafting PEEK molecular chains will facilitate the alignment of PEEK on the hBN surface, thereby forming a quasi-crystal structure. If the quasi-crystals can be regularly aligned along the direction of electromagnetic wave propagation, a liquid crystal-like polymer structure can be formed, which can effectively reduce the loss during electromagnetic wave propagation. This requires that the hBN be regularly aligned perpendicular to the direction of electromagnetic waves, which can also help to maximize the thermal conductivity of hBN.

[0044] Currently, emerging additive manufacturing (3D printing) technology is based on the principle of discrete deposition, using automated control to deposit materials layer by layer to achieve rapid manufacturing of complex parts. It offers advantages such as flexible structural design, integrated processing and molding, high manufacturing precision, and short production cycles, providing a new approach for fabricating parts with complex structures. Among these, fused deposition modeling (FDM) 3D printing is a method that melts various fusible filaments or granules by heating, then solidifies them layer by layer on a printing table to ultimately obtain a three-dimensional component. During the fused deposition process, the internal filler material orients along the path, forming anisotropic special configurations.

[0045] Therefore, FDM molding process can be used to horizontally align the grafted PEEK hBN along the printing direction, and then heat treatment can be used to form a liquid crystal-like structure with PEEK molecular weight on the hBN surface in a vertical and horizontal direction, thereby achieving high thermal conductivity and low dielectric loss.

[0046] The core principle is that the polar functional groups and dipoles in PEEK can move and align under the influence of an electric field. During this movement, they are simultaneously subjected to electric force (FE) and friction. The work done by friction leads to the dielectric loss of PEEK at high frequencies. For liquid crystal polymers, due to their highly oriented and closely packed liquid crystal structure, the movement of polar groups and dipoles perpendicular to the orientation direction is restricted. The polarization rate is effectively slowed down, reducing the work done by intermolecular friction per unit time (frictional work), thereby reducing the dielectric loss of liquid crystal PEEK at high frequencies.

[0047] This invention provides a low dielectric loss and high thermal conductivity polyetheretherketone composite material based on fused deposition modeling (FDM) 3D printing and a molding method thereof. In some embodiments, reference is made to... Figure 1 The process for preparing polyetheretherketone composite materials is as follows:

[0048] Modification of S1 and hexagonal boron nitride, refer to Figure 2 This includes the following steps:

[0049] a. Hydroxylation treatment of hexagonal boron nitride (hBN) to obtain modified boron nitride (hBN-OH) with a large number of hydroxyl functional groups on the surface.

[0050] b. By esterification of the carboxyl and hydroxyl groups, hBN-OH is converted into boron nitride (hBN-COOH) with carboxyl-terminated groups.

[0051] c. Soluble polyether ether ketone (hBN-PEEKDith) molecular chains with protected carbonyl groups are grafted onto the surface of hBN-COOH via esterification of carboxyl groups.

[0052] e. The grafted soluble polyether ether ketone is converted into polyether ether ketone with high crystallinity through a deprotection reaction, thereby obtaining hexagonal boron nitride (hBN-PEEK) with PEEK grafted on the surface.

[0053] S2. Preparation of printing filament

[0054] Modified hexagonal boron nitride (hBN-PEEK), PEEK powder, plasticizer and other raw materials are dried, blended, mixed and screw extruded to obtain printable filaments for FDM.

[0055] S3, Fused Deposition Modeling 3D Printing

[0056] Printable filaments containing hBN-PEEK were placed in an FDM device, and printing was started along the X-0° direction according to the digital model to prepare a structure with a certain thickness in which all hBN-PEEK fibers are oriented along the XY direction. Figure 5 .

[0057] S4, Heat Treatment

[0058] The obtained hBN-PEEK structure, which is oriented along the XY direction, is placed in a high-temperature oven for heat treatment, which causes the molecular chains that were not fully crystallized during the 3D printing process to recrystallize and form a liquid crystal-like structure.

[0059] The hydroxylation treatment in step S1 can be carried out by physical or chemical methods, preferably by sodium hydroxide chemical reaction, with a sodium hydroxide solution concentration of 5 mol / mL, a reaction temperature of 100 ℃, and a reaction time of 6-24 hours, preferably 12 hours.

[0060] The soluble polyether ether ketone molecular chain with the grafted carbonyl protected is preferably polyether ether ketone-1,3-dithiopentane, wherein the hydroxyl content is preferably 5%-10%.

[0061] In step S2, the hBN-PEEK content used in preparing the printing filament is 1wt% to 40wt%, preferably 20wt%.

[0062] In step S3, the diameter of the printing needle is 0.25mm, 0.4mm, 0.6mm and 0.8mm, etc. Considering printing efficiency and improving boron nitride orientation, 0.4mm is preferred.

[0063] In fused deposition modeling (FDM) 3D printing, a roll forming device can be added to improve the orientation of hBN-PEEK along the plane, while also enhancing interlayer bonding strength, such as... Figure 6 As shown.

[0064] In step S4, the heat treatment temperature is 200℃-300℃, preferably 250℃; the heat treatment time is 1-10 hours, preferably 3 hours.

[0065] The cooling method after heat treatment is programmed cooling, with a cooling rate of 0.1℃ / min-10℃ / min, preferably 0.5℃ / min.

[0066] Compared to injection-molded pure polyether ether ketone (PEEK), unmodified hexagonal boron nitride composite polyether ether ketone (hBN / PEEK), and modified hexagonal boron nitride composite polyether ether ketone (hBN-PEEK / PEEK), the modified hexagonal boron nitride composite polyether ether ketone (FDM-hBN-PEEK / PEEK) prepared by the melt deposition method provided in this invention can form such as Figure 7 and Figure 8The highly oriented and closely packed liquid crystal-like structure (regularly arranged crystal strands) shown is observed, while unmodified hBN, due to poor interfacial interactions, can only induce irregular crystal arrangement. Therefore, compared with materials prepared by other processes, FDM-hBN-PEEK / PEEK exhibits the lowest dielectric loss (0.008), the highest thermal conductivity (2.34 W / (m·K)), the lowest coefficient of friction (0.18), the highest tensile strength (123.6 MPa), the highest flexural strength (173.8 MPa), and the largest impact strength (15.4 KJ / m²). 2 ).

[0067] Table 1 shows a comparison of the performance of materials formed by different processes.

[0068] Table 1

[0069]

[0070] This invention innovatively employs FDM technology to form a highly oriented and closely packed liquid crystal-like structure. The movement of polar groups and dipoles in the liquid crystal-like polymer perpendicular to the orientation direction is restricted, and the polarization rate is effectively slowed down, reducing the work done by intermolecular friction per unit time (frictional work), thereby reducing the dielectric loss of liquid crystal-like PEEK at high frequencies.

[0071] By combining the FDM molding process with horizontally oriented hBN grafted with PEEK along the printing direction, an orderly arrangement structure resembling a "mussel" can be formed, thereby more effectively utilizing the thermal conductivity and impact resistance of boron nitride.

[0072] Based on the resulting dense composite structure, it exhibits superior mechanical properties compared to traditional methods that introduce gaps or cavities, meeting the application requirements of most scenarios.

[0073] This invention utilizes FDM printing, offering flexible structural design and optimization, high material utilization, and fewer post-processing steps. This shortens the design and manufacturing cycle, reduces production costs, and provides a rapid pathway for the development and flexible mass production of microwave absorbing components. The molding method of this invention is also applicable to various additive manufacturing processes, such as photopolymerization and direct ink writing.

[0074] The following detailed description, with reference to specific embodiments, illustrates the molding method of the polyether ether ketone composite material of the present invention and the polyether ether ketone composite material obtained by molding.

[0075] Example 1

[0076] S1, Boron nitride modification

[0077] S011. Surface hydroxylation modification of boron nitride: Hexagonal boron nitride (hBN) was used as raw material and dissolved in 5 mol / mL sodium hydroxide solution to form a 5 mg / mL dispersion. The dispersion was mechanically stirred for 12 h under oil bath heating at 100 ℃. The resulting mixture was washed multiple times until the filtrate was neutral and dried to obtain surface hydroxylation modified boron nitride (hBN-OH).

[0078] S012, Carboxylation Modification: 3g of hBN-OH was added to 50mL of terephthalic acid and dispersed by ultrasonication for 30min. Then, 50mg of anhydrous aluminum trichloride was added and magnetically stirred. The mixture was heated to 120℃ and maintained for 5 hours. After naturally cooling to room temperature, the mixture was filtered and washed to remove ungrafted terephthalic acid. The mixture was then dried at room temperature for 48 hours to obtain carboxylated boron nitride (hBN-COOH).

[0079] S013, Grafted polyether ether ketone-1,3-dithiopentane: 2.00 g of hBN-COOH was slowly added in portions to 600 mL of anhydrous N-methylpyrrolidone. After ultrasonic dispersion for 1 h, 60 g of N,N'-dicyclohexyldiimide was added, and the mixture was ultrasonically treated at 40 °C for 2 h before use.

[0080] Polyetheretherketone-1,3-dithiopentane (PEEKDith) was dissolved in 700 mL of ultra-dry tetrahydrofuran. After complete dissolution under magnetic stirring, 32.4 g of N,N'-dicyclohexyldiimide and 6.8 g of 4-dimethylaminopyridine were added. After complete dissolution, the polymer solution was rapidly poured into an hBN-COOH dispersion under ultrasonic conditions, and the reaction was continued at 60 °C for 96 h. After the reaction was completed, the reactants were filtered to obtain a solid product. Then, using a Soxhlet extractor, the product was washed sequentially with anhydrous N-methylpyrrolidone, tetrahydrofuran, and ethanol for 4 h, and dried to obtain polyetheretherketone-1,3-dithiopentane grafted boron nitride, labeled as hBN-PEEKDith. Figure 3 .

[0081] S014, Deprotection: Slowly pour 2.7 g of hBN-PEEKDith into 340 mL of chloroform, sonicate for 1 h, then rapidly add 35 mL of dimethyl sulfoxide and 27 mL of 2-iodo-2-methylpropane, and sonicate again for 24 h. Then, install a reflux condenser and heat to 65 °C for 48 h. After the reaction, filter the reactants to obtain a solid product. Then, use a Soxhlet extractor, wash with methanol for 4 h, and dry to obtain polyetheretherketone grafted boron nitride, labeled as hBN-PEEK, as shown below. Figure 4 .

[0082] S2. Preparation of printing filament

[0083] S021. Mixing: Pour 200g of hBN-PEEK and 800g of PEEK powder into the mixing drum of the V-type mixer, and add grinding balls of different diameters. Start the drive motor and set the parameters: speed of 50r / min and mixing time of 8 hours. After mixing is completed, take out the mixture from the outlet.

[0084] S022. Drying: Since the powder mixing time is as long as 8 hours, in order to ensure the extrusion quality, the mixed powder needs to be dried. The drying temperature is set at 120℃ and the drying time is 12 hours.

[0085] S023, Screw Extrusion: The blended, dispersed, and dried hBN-PEEK / PEEK mixed powder is added to the feed port of the screw extruder. Passing through different heating zones, the powder undergoes a transformation from a solid state to a glassy state and then to a viscous flow state. Finally, the composite material filaments are extruded from the die. After being cooled by air blowing in a cooling tank, the filaments are wound by a traction wheel to obtain the product. The temperatures in zones 1-7 are 327℃, 339℃, 343℃, 346℃, 345℃, 343℃, and 341℃, respectively, and the screw speed is 35 r·min. -1 The winding speed is 11 mm / s. -1 .

[0086] S3, Fused Deposition Modeling 3D Printing

[0087] The model to be printed is drawn using Materialise Magics software, and then sliced ​​using Cura software. Before printing, the printability of the filament needs to be tested to determine the appropriate printing rate and slice thickness.

[0088] A printing filament containing 20 wt% hBN-PEEK was placed in an FDM device with a nozzle diameter of 0.4 mm. Printing was started along the X-0° direction according to the digital model to prepare a structure with a certain thickness of hBN-PEEK oriented along the XY direction.

[0089] S4, Heat Treatment

[0090] The printed material was placed in a heat treatment furnace with programmable temperature control. The temperature was first raised to 250°C at a rate of 5°C / min and held for 3 hours. Then, the heat treatment furnace was slowly cooled to room temperature at a rate of 0.5°C / min. Finally, the sample was removed to prepare a polyetheretherketone composite material with low dielectric loss and high thermal conductivity.

[0091] The performance of the polyether ether ketone composite material prepared in Example 1 was tested, and the test data are shown in Table 1.

[0092] Certain terms are used in the specification and claims to refer to specific components. Those skilled in the art will understand that hardware manufacturers may use different names to refer to the same component. This specification and claims do not distinguish components based on differences in name, but rather on differences in function. The terms "comprising" and "including" used throughout the specification and claims are open-ended and should be interpreted as "comprising / including but not limited to". "Approximately" means that within an acceptable margin of error, those skilled in the art can solve the technical problem and substantially achieve the technical effect within a certain margin of error. The following descriptions in the specification are preferred embodiments for carrying out this application; however, these descriptions are for the purpose of illustrating the general principles of this application and are not intended to limit the scope of this application. The scope of protection of this application shall be determined by the appended claims.

[0093] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a product or system comprising a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a product or system. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the product or system that includes said element.

[0094] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0095] The foregoing description illustrates and describes several preferred embodiments of this application. However, as previously stated, it should be understood that this application is not limited to the forms disclosed herein and should not be construed as excluding other embodiments. It can be used in various other combinations, modifications, and environments, and can be altered within the scope of the application concept described herein through the foregoing teachings or techniques or knowledge in related fields. Any modifications and variations made by those skilled in the art that do not depart from the spirit and scope of this application should be within the protection scope of the appended claims.

Claims

1. A method for molding polyetheretherketone composite materials, characterized in that, Includes the following steps: S01. Hexagonal boron nitride is modified to obtain hexagonal boron nitride hBN-PEEK with PEEK grafted on the surface. S02. A printing filament suitable for FDM was prepared using modified hexagonal boron nitride (hBN-PEEK), PEEK powder, and a plasticizer. S03. Using the prepared printing filament, printing was started along the X-0° direction according to the digital model to prepare a structure in which hBN-PEEK is oriented along the XY direction; S04. The obtained hBN-PEEK structure, which is oriented along the XY direction, is subjected to heat treatment to allow the incompletely crystallized molecular chains to recrystallize and form a liquid crystal-like structure of hBN-PEEK.

2. The molding method for polyetheretherketone composite materials according to claim 1, characterized in that, The steps for modifying hexagonal boron nitride include: S011. Hydroxylation treatment of hexagonal boron nitride hBN is performed to obtain modified boron nitride hBN-OH with hydroxyl functional groups on the surface. S012. By esterification of carboxyl and hydroxyl groups, hBN-OH is converted into boron nitride hBN-COOH with carboxyl-terminal groups modified. S013. Soluble polyether ether ketone molecular chains with protected carbonyl groups are grafted onto the surface of hBN-COOH via esterification of carboxyl groups. S014. The grafted soluble polyether ether ketone is converted by a deprotection reaction to obtain hexagonal boron nitride hBN-PEEK with PEEK grafted on the surface.

3. The molding method for polyetheretherketone composite materials according to claim 2, characterized in that, In step S011, hydroxylation is performed using a sodium hydroxide chemical reaction method. The concentration of the sodium hydroxide solution is 5 mol / mL, the reaction temperature is 100 ℃, and the reaction time is 6-24 hours.

4. The molding method for polyetheretherketone composite materials according to claim 2, characterized in that, In step S013, a soluble polyether ether ketone (PEEK) molecular chain with a carbonyl protected grafted onto a polyether ether ketone-1,3-dithiopentane is used, and the hydroxyl content of the polyether ether ketone-1,3-dithiopentane is 5%-10%.

5. The molding method for polyetheretherketone composite materials according to claim 1, characterized in that, In step S02, the hBN-PEEK content used in preparing the printing filament is 1wt% to 40wt%.

6. The molding method for polyetheretherketone composite materials according to claim 1, characterized in that, In step S03, during the fused deposition modeling (FDM) 3D printing operation, the obtained hBN-PEEK structure, which is oriented along the XY direction, is subjected to a roll forming operation using a roll forming device.

7. The molding method for polyetheretherketone composite materials according to claim 1, characterized in that, In step S04, the heat treatment temperature is 200℃-300℃, the heat treatment time is 1-10 hours, and the cooling rate after heat treatment is 0.1℃ / min - 10℃ / min.

8. The polyetheretherketone composite material prepared by the molding method of any one of claims 1-7.

9. A polyetheretherketone composite material, characterized in that, The polyetheretherketone composite material is prepared from raw materials made of modified hexagonal boron nitride and PEEK powder. The hexagonal boron nitride hBN-PEEK grafted with PEEK is prepared by fused deposition modeling and has a structure in which all the surface grafted PEEK is oriented along the XY direction. After heat treatment, the hBN-PEEK is formed into a liquid crystal-like structure.

10. The polyetheretherketone composite material according to claim 9, characterized in that, The modified hexagonal boron nitride is hexagonal boron nitride hBN-PEEK with PEEK grafted on the surface.

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