PEEK composite material with high wear resistance and preparation method thereof

Abstract

The invention relates to the technical field of high polymer materials, and discloses a PEEK composite material with high wear resistance and a preparation method thereof, the PEEK composite material comprises the following components by weight: 50-70 parts of PEEK resin, 10-20 parts of PTFE resin, 6-10 parts of modified carbon fiber, 4-6 parts of a modified Ti3C2Tx MXene material, and 1-2 parts of a silicone composite lubricant; the modified carbon fiber is prepared by depositing a PDA coating on the surface of the carbon fiber and then directionally grafting nano ZrO2 through ultraviolet light; the modified Ti < 3 > C < 2 > T < x > MXene material is prepared by the following steps: hybridizing Ti < 3 > C < 2 > T < x > MXene prepared by an HF etching method with graphene oxide, performing ammonification reduction, and loading cobalt by an impregnation-pyrolysis method; the PTFE resin and the PEEK resin are compounded, the modified carbon fiber and the modified Ti3C2Tx MXene are added, the modified carbon fiber is mainly used for enhancing rigidity and interface bonding, the modified Ti3C2Tx MXene is used for optimizing lubrication and crack inhibition, and the PTFE resin and the modified Ti3C2Tx MXene synergistically improve the mechanical property and the wear resistance of the PEEK composite material.

Description

Technical Field

[0001] The invention belongs to the technical field of polymer materials, and particularly relates to a PEEK composite material with high wear resistance and a preparation method thereof. Background Art

[0002] Polyetheretherketone (PEEK) is a high-performance engineering polymer characterized by high toughness, low density, a high glass transition temperature and melting point, and excellent resistance to organic solvents, acids, and bases. Therefore, it is considered a potential alternative to alloy components in the aerospace, biomedical, and precision manufacturing sectors. However, with the rapid development of the manufacturing industry, the speed and load of power machinery are increasing. Coupled with environmental protection requirements, the load-bearing capacity and friction properties of a single PEEK material are insufficient to meet diverse application requirements. Therefore, optimizing its overall performance requires the most effective method: material composites.

[0003] Common modification techniques for PEEK composites include filling modification, blending modification, and surface modification. Carbonaceous materials such as carbon fibers (CFs), carbon nanotubes (CNTs), and graphene are commonly used reinforcing materials for PEEK-based composites, with advantages such as low density, high strength, and low cost. In particular, compared with CFs and CNTs, graphene, with its two-dimensional characteristics, not only has excellent mechanical properties but also has potential low shear resistance, which is beneficial to improving the tribological properties of PEEK. However, the interfacial bonding strength between simple inorganic nanomaterials such as carbon fibers (CFs), carbon nanotubes (CNTs), and graphene and the matrix is ​​low, making it difficult for the two to directly produce chemical bonds to form a good interfacial phase, resulting in unsatisfactory tribological properties of the composites. Summary of the Invention

[0004] In order to solve the deficiencies mentioned in the above background technology, the purpose of the present invention is to provide a PEEK composite material with high wear resistance and a preparation method thereof, by compounding PTFE resin with PEEK resin and adding modified carbon fiber and modified Ti3C2T x MXene, modified carbon fiber mainly enhances rigidity and interface bonding, while modified Ti3C2T x MXene optimizes lubrication and crack suppression, and the two synergistically improve the mechanical properties and wear resistance of PEEK composites.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] A PEEK composite material with high wear resistance, comprising the following components by weight: 50-70 parts of PEEK resin, 10-20 parts of PTFE resin, 6-10 parts of modified carbon fiber, and modified Ti3C2T x 4-6 parts of MXene material, 1-2 parts of silicone composite lubricant;

[0007] The modified carbon fiber is prepared by depositing a PDA coating on the carbon fiber surface and then directional grafting nano ZrO2 using ultraviolet light;

[0008] The modified Ti3C2T x MXene material is Ti3C2T prepared by HF etching x MXene was hybridized with graphene oxide, and then reduced by ammonia and loaded with cobalt via an impregnation-pyrolysis method.

[0009] Preferably, the PEEK resin has a number average molecular weight of 18,000 to 22,000 g / mol, a polydispersity index (PDI) of 2 to 2.2, and a melt index of 45 to 55 g / 10 min; the PTFE resin has a molecular weight of 500,000 to 2,000,000 g / mol and an average particle size of 5 to 10 μm.

[0010] Preferably, the modified carbon fiber preparation method comprises the following steps:

[0011] A1. The carbon fibers were washed with acetone and deionized water in sequence and then vacuum dried. The carbon fibers were then treated in a low-temperature oxygen plasma apparatus for 5 to 10 minutes. Dopamine hydrochloride was dissolved in Tris-HCl buffer and ultrasonically dispersed for 20 to 40 minutes. The treated carbon fibers were immersed in the solution and magnetically stirred at 25°C for 6 to 10 hours to form a polydopamine layer.

[0012] A2, immersing the polydopamine-coated carbon fiber in an ethanol solution of 3-mercaptopropyltriethoxysilane, reacting at 50°C for 3-5 hours, centrifuging and washing, and then vacuum drying to obtain a surface mercaptan-modified carbon fiber;

[0013] A3. Disperse nano-ZrO2 in toluene, add vinyltrimethoxysilane, and reflux at 110°C for 10-12 hours under nitrogen protection. Centrifuge, wash, and vacuum dry to obtain vinyl-modified nano-ZrO2.

[0014] A4. Disperse vinyl-modified nano-ZrO2 in anhydrous ethanol, add polyvinyl pyrrolidone, and ultrasonically treat for 40 to 60 minutes. Then, immerse the carbon fiber obtained in A2 in the nano-ZrO2 dispersion, deoxygenate with nitrogen for 5 to 10 minutes, and irradiate under ultraviolet light for 10 to 20 minutes to induce a thiol-ene reaction, and graft nano-ZrO2 on the surface of the PAD coating to obtain the modified carbon fiber.

[0015] Preferably, in step A1, the mass ratio of dopamine hydrochloride to carbon fiber is 1:5-10.

[0016] Preferably, in step A4, the mass ratio of vinyl-modified nano ZrO2 to surface hydrophobic carbon fiber is 1:10-20.

[0017] Preferably, the wavelength of ultraviolet light is 360-370 nm, and the intensity is 20-40 mW / cm 2 .

[0018] Preferably, the modified Ti3C2T x The preparation method of MXene material includes the following steps:

[0019] B1. Slowly add MAX phase Ti3AlC2 into HF and stir at 35℃ for 20-24h. Centrifuge and wash the acidic precipitate until the supernatant is neutral. Ultrasonicate in an ice bath and centrifuge repeatedly to collect the upper dispersion to obtain Ti3C2T x MXene dispersion;

[0020] B2. Add graphene oxide to deionized water and ultrasonically disperse for 10 to 20 minutes to obtain graphene oxide dispersion. Then, x The MXene dispersion and graphene oxide dispersion were mixed and ultrasonic dispersion was continued for 20-40 min. The dispersion was freeze-dried and placed in a tube furnace. A mixture of NH3 and Ar was introduced and heated to 600 °C for 1-3 h to generate TiN / Ti3C2T x / N-rGO heterostructure;

[0021] B3, TiN / Ti3C2T x The N-rGO heterostructure was ultrasonically mixed with ZIF-67 in methanol for 1-2 h, dried in vacuo at 60 °C, placed in an Ar atmosphere, and heated to 900 °C at a heating rate of 5 °C / min and annealed for 1 h to obtain the modified Ti3C2T x MXene materials.

[0022] Preferably, in step B2, graphene oxide and Ti3C2T x The mass ratio of MXene is 1:1 to 1.2, and NH3 and Ar are mixed in a volume ratio of 1:4.

[0023] Preferably, in step B3, TiN / Ti3C2T x The mass ratio of / N-rGO heterostructure to ZIF-67 is 2-4:1, and the modified Ti3C2T x The Co single atom loading in MXene materials is 1 to 1.2 wt%.

[0024] A method for preparing a PEEK composite material with high wear resistance comprises the following steps:

[0025] (1) PEEK resin and PTFE resin were vacuum dried at 120℃ for 4-6h, and the modified Ti3C2T xThe MXene material and PTFE oligomer were ultrasonically mixed in ethanol for 40-60 min, filtered and vacuum dried to obtain pretreated modified Ti3C2T x MXene materials;

[0026] (2) Then PEEK resin, PTFE resin, modified carbon fiber and pretreated modified Ti3C2T x MXene material was added to the extruder, and the extruder temperature was zoned: zone 1 340°C, zone 2 360°C, zone 3 380°C, zone 4 380°C;

[0027] (3) applying a horizontal magnetic field in the third zone of the extruder barrel with a magnetic field intensity of 0.5 T, a screw speed of 150 rpm, and a residence time of 2 to 4 min, and water-cooling and pelletizing the extruded strips to obtain composite particles;

[0028] (4) The composite particles are placed in a mold, preheated at 385° C. for 8 to 10 minutes, maintained at a pressure of 20 MPa for 12 to 15 minutes, quenched in cold water to set the shape, and finally annealed at 200° C. for 1 to 3 hours to obtain the PEEK composite material with high wear resistance.

[0029] Beneficial effects of the present invention:

[0030] The PEEK composite material with high wear resistance of the present invention is compounded by PTFE resin and PEEK resin, and modified carbon fiber and modified Ti3C2T are added. x MXene, modified carbon fiber mainly enhances rigidity and interface bonding, while modified Ti3C2T x MXene optimizes lubrication and crack suppression, and the two synergistically improve the mechanical properties and wear resistance of PEEK composites.

[0031] The phenolic hydroxyl / amino groups in the modified carbon fiber PDA layer of the present invention form hydrogen bonds and Michael addition reactions with the carboxyl groups on the carbon fiber surface, achieving strong adhesion and simultaneously improving the compatibility of the carbon fiber with the resin matrix. Furthermore, -SH groups are introduced to the carbon fiber surface of the PDA layer. UV light is used to initiate a reaction between the vinyl-modified nano-ZrO2 and the -SH groups, achieving high-density grafting and forming a granular, rough surface on the carbon fiber surface, thereby enhancing the interfacial bonding strength with the resin matrix. The ZrO2 nanoparticles also increase the rigidity and flexural stiffness of the carbon fiber, reducing fiber breakage. Furthermore, the ZrO2 nanoparticles also increase the surface hardness of the composite material, reducing abrasive wear and enhancing wear resistance.

[0032] Modified Ti3C2T x MXene is hybridized with Ti3C2Tx MXene and graphene, and in-situ amination treatment is used to transform Ti3C2T xPartial conversion into TiN nanocrystals increases hardness. During friction, MXene bears the primary load, while graphene releases shear stress, reducing the material's wear rate. Cobalt is loaded on the MXene surface as a catalytic site. At PEEK processing temperature (380°C), Co-SA catalyzes the reaction between the benzene rings in the PEEK molecular chain and the -Ti bonds on the MXene surface, forming a Ti-C covalent interface layer. During friction, local high temperatures can also trigger Co-SA to continuously catalyze the generation of Ti-C, reducing the friction coefficient and thus improving the wear resistance of the composite material. In addition, the MXene / GO layered structure hinders crack propagation, improves toughness, and enhances the bending properties of the composite material. Cobalt nanoparticles promote PEEK crystallization, increasing the modulus and enhancing mechanical properties.

[0033] The present invention utilizes magnetic field-assisted molding in the preparation of a highly wear-resistant PEEK composite. A 0.5T horizontal magnetic field is applied during PEEK melt blending, aligning the paramagnetic MXene (paramagnetic) along the shear force, forming a "nano-armor" parallel to the friction surface. Graphene is also functionalized and grafted with a fluoropolymer (PTFE oligomer). The fluorine atoms released by frictional heat form a low-shear Ti-F interface with the MXene. This oriented alignment aligns the wear direction with the reinforcement phase, further reducing the friction coefficient and improving the wear resistance of the PEEK composite. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0035] Figure 1 1 is an SEM image of the unmodified carbon fiber, the polydopamine-coated carbon fiber, and the modified carbon fiber with nano-zirconium dioxide grafted on the surface in Example 1;

[0036] Figure 2 It is TiN / Ti3C2T in Example 2 x / N-rGO heterostructure and modified Ti3C2T x SEM image of MXene material. DETAILED DESCRIPTION

[0037] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0038] Example 1

[0039] A method for preparing modified carbon fiber comprises the following steps:

[0040] A1. 3.8 g of glass fiber was washed with acetone and deionized water in sequence, then vacuum dried. The fiber was then treated in a low-temperature oxygen plasma apparatus for 5-10 minutes to introduce active groups and increase roughness to improve the adhesion of subsequent coatings. 0.5 g of dopamine hydrochloride was dissolved in Tris-HCl buffer at a solid-liquid ratio of 2 mg:1 mL, and ultrasonically dispersed for 30 minutes. The treated glass fiber was immersed in the solution and magnetically stirred at 25°C for 8 hours to form a polydopamine layer.

[0041] A2. Immerse the obtained polydopamine-coated carbon fiber in 50 ml of 2 Vol% 3-mercaptopropyltriethoxysilane ethanol solution, react at 50° C. for 4 h, centrifuge, wash with ethanol three times, and vacuum dry at 80° C. to obtain surface thiolated carbon fiber;

[0042] A3. Disperse 1.2 g of nano-zirconium dioxide in 50 mL of toluene, add 2 mL of vinyltrimethoxysilane, and ultrasonically treat for 30 min. Under nitrogen protection, reflux at 110° C. for 12 h. The Si-OH group after hydrolysis of vinyltrimethoxysilane condenses with the hydroxyl group on the surface of zirconium dioxide to form Si-O-Si bonds, and vinyl groups (-CH=CH2) are grafted. After centrifugation, wash with toluene three times, and dry in vacuo at 80° C. to obtain vinyl-modified nano-zirconium dioxide.

[0043] A4, 0.5g of vinyl modified nano zirconium dioxide was dispersed in 100ml of ethanol, 0.01g of polyvinyl pyrrolidone was added, and ultrasonication was performed for 50min. 7.5g of surface thiolated carbon fiber was immersed in the nano zirconium dioxide dispersion, and nitrogen was passed through to deoxygenate for 10min. 2 The modified carbon fiber was irradiated with ultraviolet light (wavelength 365 nm) for 15 min to induce a thiol-ene reaction and grafted with nano-zirconium dioxide on the surface of the polydopamine layer of the carbon fiber. The carbon fiber was centrifuged, washed with ethanol three times, and dried in vacuum at 80° C. to obtain the modified carbon fiber.

[0044] Scanning electron microscopy analysis was performed on unmodified carbon fiber, polydopamine coated carbon fiber and modified carbon fiber with surface grafted nano zirconium dioxide, and the SEM images were obtained as follows: Figure 1 shown. Figure 1 a is the SEM morphology of unmodified carbon fiber, which has a smooth and slender surface. Figure 1 b is the SEM morphology of polydopamine coated carbon fiber. Compared with the unmodified carbon fiber in 1a, it can be seen that its surface is covered with a coating, which increases the fiber diameter. Figure 1c is the SEM morphology of the surface-modified carbon fiber. It can be seen that there are obvious nano-scale particles on the surface of the polydopamine layer, indicating that nano-zirconium dioxide has been successfully grafted.

[0045] Example 2

[0046] A modified Ti3C2T x The preparation method of MXene material includes the following steps:

[0047] B1. Slowly add 5.0 g of MAX phase Ti3AlC2 into 50 mL of 40 Vol% HF and stir at 35 °C for 24 h. Centrifuge and wash the acidic precipitate until the supernatant is neutral. Ultrasonicate in an ice bath and centrifuge repeatedly to collect the upper dispersion to obtain Ti3C2T x MXene dispersion;

[0048] B2, 4.6g of graphene oxide was added to 50ml of deionized water and ultrasonically dispersed for 15min to obtain a graphene oxide dispersion, and then Ti3C2T x The MXene dispersion and graphene oxide dispersion were mixed and ultrasonic dispersion was continued for 30 min. The dispersion was freeze-dried and placed in a tube furnace. A mixture of NH3 and Ar (NH3:Ar=1:4) was introduced and heated to 600℃ for 2 h to generate TiN / Ti3C2T x / N-rGO heterostructure;

[0049] B3, 7.2g TiN / Ti3C2T x The Ti3C2T / N-rGO heterostructure was ultrasonically mixed with 2.6 g ZIF-67 in 100 mL methanol for 1.5 h, dried under vacuum at 60 °C, and placed in an Ar atmosphere. The temperature was raised to 900 °C at a heating rate of 5 °C / min and annealed for 1 h to obtain the modified Ti3C2T x MXene material, with a Co loading of 1.2 wt%.

[0050] The prepared TiN / Ti3C2T x / N-rGO heterostructure and modified Ti3C2T x The MXene material was subjected to scanning electron microscopy analysis, and the SEM images were obtained as follows: Figure 2 shown. Figure 2 a, 2b are TiN / Ti3C2T x From the SEM morphology of the Mg / N-rGO heterostructure, it can be seen that MXene and graphene oxide are evenly dispersed, and there are obvious wrinkles on the surface. Figure 2 c and 2d are modified Ti3C2T x The SEM morphology of MXene material shows that a large area of ​​particles are uniformly adhered to the TiN / Ti3C2Tx The surface of the / N-rGO heterostructure indicates the successful loading of metallic cobalt nanoparticles.

[0051] Example 3

[0052] A PEEK composite material with high wear resistance, comprising the following components by weight: 50 parts of PEEK resin, 20 parts of PTFE resin, 6 parts of modified carbon fiber, and modified Ti3C2T x 6 parts of MXene material and 1 part of silicone composite lubricant; PEEK resin number average molecular weight of 18000-22000 g / mol, polydispersity index PDI of 2-2.2, melt index of 45-55 g / 10 min; PTFE resin molecular weight of 500000-2000000 g / mol, average particle size of 5-10 μm; modified carbon fiber prepared by the method in Example 1; the modified Ti3C2T x The MXene material was prepared by the method in Example 2.

[0053] The method for preparing the above-mentioned PEEK composite material with high wear resistance comprises the following steps:

[0054] (1) PEEK resin and PTFE resin were vacuum dried at 120℃ for 6h, and the modified Ti3C2T x The MXene material and PTFE oligomer were ultrasonically mixed in ethanol for 40 min, filtered and vacuum dried to obtain pretreated modified Ti3C2T x MXene materials;

[0055] (2) Then PEEK resin, PTFE resin, modified carbon fiber and pretreated modified Ti3C2T x MXene material was added to the extruder, and the extruder temperature was zoned: zone 1 340°C, zone 2 360°C, zone 3 380°C, zone 4 380°C;

[0056] (3) applying a horizontal magnetic field in the third zone of the extruder barrel with a magnetic field intensity of 0.5 T, a screw speed of 150 rpm, and a residence time of 4 min, and then water-cooling and pelletizing the extruded strips to obtain composite particles;

[0057] (4) The composite particles were placed in a mold, preheated at 385°C for 8 minutes, maintained at a pressure of 20 MPa for 15 minutes, quenched in cold water to set the shape, and finally annealed at 200°C for 1 hour to obtain the PEEK composite material with high wear resistance.

[0058] Example 4

[0059] A PEEK composite material with high wear resistance, comprising the following components by weight: 70 parts of PEEK resin, 10 parts of PTFE resin, 10 parts of modified carbon fiber, and modified Ti3C2T x 4 parts of MXene material and 2 parts of silicone composite lubricant; PEEK resin number average molecular weight of 18000-22000 g / mol, polydispersity index PDI of 2-2.2, melt index of 45-55 g / 10 min; PTFE resin molecular weight of 500000-2000000 g / mol, average particle size of 5-10 μm; modified carbon fiber prepared by the method in Example 1; the modified Ti3C2T x The MXene material was prepared by the method in Example 2.

[0060] The method for preparing the above-mentioned PEEK composite material with high wear resistance comprises the following steps:

[0061] (1) PEEK resin and PTFE resin were vacuum dried at 120℃ for 4h, and the modified Ti3C2T x The MXene material and PTFE oligomer were ultrasonically mixed in ethanol for 60 min, filtered and vacuum dried to obtain pretreated modified Ti3C2T x MXene materials;

[0062] (2) Then PEEK resin, PTFE resin, modified carbon fiber and pretreated modified Ti3C2T x MXene material was added to the extruder, and the extruder temperature was zoned: zone 1 340°C, zone 2 360°C, zone 3 380°C, zone 4 380°C;

[0063] (3) applying a horizontal magnetic field in the third zone of the extruder barrel with a magnetic field intensity of 0.5 T, a screw speed of 150 rpm, and a residence time of 2 min, and water-cooling and pelletizing the extruded strips to obtain composite particles;

[0064] (4) The composite particles are placed in a mold, preheated at 385° C. for 10 min, maintained at a pressure of 20 MPa for 12 min, quenched in cold water to set the shape, and finally annealed at 200° C. for 3 h to obtain the PEEK composite material with high wear resistance.

[0065] Example 5

[0066] A PEEK composite material with high wear resistance, comprising the following components by weight: 60 parts of PEEK resin, 15 parts of PTFE resin, 8 parts of modified carbon fiber, and modified Ti3C2T x5 parts of MXene material and 1.5 parts of silicone composite lubricant; PEEK resin number average molecular weight of 18000-22000 g / mol, polydispersity index PDI of 2-2.2, melt index of 45-55 g / 10 min; PTFE resin molecular weight of 500000-2000000 g / mol, average particle size of 5-10 μm; modified carbon fiber prepared by the method in Example 1; the modified Ti3C2T x The MXene material was prepared by the method in Example 2.

[0067] The method for preparing the above-mentioned PEEK composite material with high wear resistance comprises the following steps:

[0068] (1) PEEK resin and PTFE resin were vacuum dried at 120℃ for 5h, and the modified Ti3C2T x The MXene material and PTFE oligomer were ultrasonically mixed in ethanol for 50 min, filtered and vacuum dried to obtain pretreated modified Ti3C2T x MXene materials;

[0069] (2) Then PEEK resin, PTFE resin, modified carbon fiber and pretreated modified Ti3C2T x MXene material was added to the extruder, and the extruder temperature was zoned: zone 1 340°C, zone 2 360°C, zone 3 380°C, zone 4 380°C;

[0070] (3) applying a horizontal magnetic field in the third zone of the extruder barrel with a magnetic field intensity of 0.5 T, a screw speed of 150 rpm, and a residence time of 3 min, and then water-cooling and pelletizing the extruded strips to obtain composite particles;

[0071] (4) The composite particles are placed in a mold, preheated at 385° C. for 10 min, maintained at a pressure of 20 MPa for 15 min, quenched in cold water to set the shape, and finally annealed at 200° C. for 2 h to obtain the PEEK composite material with high wear resistance.

[0072] Comparative Example 1

[0073] A PEEK composite material with high wear resistance, comprising the following components by weight: 60 parts of PEEK resin, 15 parts of PTFE resin, 8 parts of carbon fiber, and modified Ti3C2T x 5 parts of MXene material, 1.5 parts of silicone composite lubricant; PEEK resin number average molecular weight 18000-22000 g / mol, polydispersity index PDI 2-2.2, melt index 45-55 g / 10 min; PTFE resin molecular weight 500000-2000000 g / mol, average particle size 5-10 μm; the modified Ti3C2T xThe MXene material was prepared by the method in Example 2.

[0074] The method for preparing the above-mentioned PEEK composite material with high wear resistance comprises the following steps:

[0075] (1) PEEK resin and PTFE resin were vacuum dried at 120℃ for 5h, and the modified Ti3C2T x The MXene material and PTFE oligomer were ultrasonically mixed in ethanol for 50 min, filtered and vacuum dried to obtain pretreated modified Ti3C2T x MXene materials;

[0076] (2) Then PEEK resin, PTFE resin, carbon fiber and pretreated modified Ti3C2T x MXene material was added to the extruder, and the extruder temperature was zoned: zone 1 340°C, zone 2 360°C, zone 3 380°C, zone 4 380°C;

[0077] (3) applying a horizontal magnetic field in the third zone of the extruder barrel with a magnetic field intensity of 0.5 T, a screw speed of 150 rpm, and a residence time of 3 min, and then water-cooling and pelletizing the extruded strips to obtain composite particles;

[0078] (4) The composite particles are placed in a mold, preheated at 385° C. for 10 min, maintained at a pressure of 20 MPa for 15 min, quenched in cold water to set the shape, and finally annealed at 200° C. for 2 h to obtain the PEEK composite material with high wear resistance.

[0079] Comparative Example 2

[0080] A PEEK composite material with high wear resistance, comprising the following components by weight: 60 parts of PEEK resin, 15 parts of PTFE resin, 8 parts of modified carbon fiber, Ti3C2T x 5 parts of MXene material and 1.5 parts of silicone composite lubricant; PEEK resin with a number average molecular weight of 18000-22000 g / mol, a polydispersity index PDI of 2-2.2, and a melt index of 45-55 g / 10 min; PTFE resin with a molecular weight of 500000-2000000 g / mol and an average particle size of 5-10 μm; modified carbon fiber prepared by the method in Example 1; Ti3C2T x The MXene material is Ti3C2T prepared by step B1 in Example 2. x MXene dispersion was directly freeze-dried to obtain unmodified Ti3C2T x MXene materials.

[0081] The method for preparing the above-mentioned PEEK composite material with high wear resistance comprises the following steps:

[0082] (1) PEEK resin and PTFE resin were vacuum dried at 120℃ for 5h, and Ti3C2T x The MXene material and PTFE oligomer were ultrasonically mixed in ethanol for 50 min, filtered and vacuum dried to obtain pretreated Ti3C2T x MXene materials;

[0083] (2) Then PEEK resin, PTFE resin, modified carbon fiber and pretreated Ti3C2T x MXene material was added to the extruder, and the extruder temperature was zoned: zone 1 340°C, zone 2 360°C, zone 3 380°C, zone 4 380°C;

[0084] (3) applying a horizontal magnetic field in the third zone of the extruder barrel with a magnetic field intensity of 0.5 T, a screw speed of 150 rpm, and a residence time of 3 min, and then water-cooling and pelletizing the extruded strips to obtain composite particles;

[0085] (4) The composite particles are placed in a mold, preheated at 385° C. for 10 min, maintained at a pressure of 20 MPa for 15 min, quenched in cold water to set the shape, and finally annealed at 200° C. for 2 h to obtain the PEEK composite material with high wear resistance.

[0086] Performance testing

[0087] 1. Mechanical properties test

[0088] The mechanical properties of the PEEK composite materials with high wear resistance obtained in Examples 3 to 5 and Comparative Examples 1 to 2 were tested, and the tensile properties were tested with reference to GB / T 1040.1-2018. Standard type I specimens were prepared and tested on an electronic universal testing machine with a tensile speed of 5 mm / min. The stress-strain curve was recorded, and the tensile strength (MPa), elastic modulus (GPa) and elongation at break (%) were calculated. The bending properties were tested with reference to GB / T 9341-2008. The three-point bending method with a span of 64 mm and a loading rate of 2 mm / min was used to determine the bending strength (MPa) and bending modulus. The impact properties were tested with reference to GB / T 1843-2008. A V-notch specimen was used to determine the impact strength (kJ / m 2 ). The test results are shown in Table 1 below.

[0089] Table 1 Mechanical properties test results of PEEK composite materials with high wear resistance

[0090]

[0091]

[0092] As can be seen from the data in Table 1, the tensile properties, bending properties and impact properties of the PEEK composite materials in Comparative Examples 1 and 2 have all decreased, indicating that the modified carbon fibers and modified Ti3C2Tx MXene materials of the present invention synergistically improve the mechanical properties of the PEEK composite materials. The PDA coating strengthens the bonding of the fibers to the matrix, the ZrO2 nanoparticles improve the rigidity, significantly improving the tensile strength, the GO / MXene hybrid structure is evenly dispersed, and the cobalt nanoparticles promote PEEK crystallization, increase the modulus, and improve the tensile properties of the composite material. The ZrO2 grafted carbon fibers enhance flexural rigidity and reduce fiber breakage, while the MXene / GO layered structure hinders crack propagation, improves toughness, and improves the bending properties of the composite material. The PDA layer improves interfacial toughness, reduces fiber debonding during impact, and the cobalt nanoparticles induce plastic deformation, absorb impact energy, and improve the impact properties of the composite material.

[0093] 2. Wear resistance test

[0094] The wear resistance of the PEEK composite materials with high wear resistance obtained in Examples 4 to 6 and Comparative Examples 1 to 2 was tested. The sliding wear test was carried out in accordance with GB / T 3960-2016. A ring-block friction tester was used, the grinding pair was a GCr15 steel ring, the load was 50N, the speed was 200r / min, and the test time was 60min. The wear amount (mg) was measured and converted into the wear rate (mm 3 / N·m), and record the friction coefficient at the same time, and the data are shown in Table 2 below.

[0095] Table 2 Wear resistance test results of PEEK composite materials with high wear resistance

[0096]

[0097] It can be seen from the data in Table 2 that the wear resistance of the PEEK composite materials in Comparative Examples 1 and 2 is lower than that in Examples 3 and 4. x MXene materials synergistically improve the wear resistance of PEEK composites. ZrO2 particles increase surface hardness and reduce abrasive wear. MXene / GO releases a lubricating film, and cobalt catalyzes the formation of a carbon-based protective layer, reducing the friction coefficient, thereby improving the wear resistance of the composite material.

[0098] Throughout this specification, references to terms such as "one embodiment," "example," or "specific example" indicate that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0099] The basic principles, main features, and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention, and such changes and modifications fall within the scope of the invention as claimed.

Claims

1. A PEEK composite material with high wear resistance, characterized in that: The invention comprises the following components by weight: 50-70 parts of PEEK resin, 10-20 parts of PTFE resin, 6-10 parts of modified carbon fiber, and modified Ti3C2T x 4-6 parts of MXene material, 1-2 parts of silicone composite lubricant; The modified carbon fiber is prepared by depositing a PDA coating on the carbon fiber surface and then directional grafting nano ZrO2 using ultraviolet light; The modified Ti3C2T x MXene material is Ti3C2T prepared by HF etching x MXene was hybridized with graphene oxide, and then reduced by ammonia and loaded with cobalt via an impregnation-pyrolysis method.

2. The PEEK composite material with high wear resistance according to claim 1, characterized in that: The PEEK resin has a number average molecular weight of 18,000 to 22,000 g / mol, a polydispersity index (PDI) of 2 to 2.2, and a melt index of 45 to 55 g / 10 min. The PTFE resin has a molecular weight of 500,000 to 2,000,000 g / mol and an average particle size of 5 to 10 μm.

3. The PEEK composite material with high wear resistance according to claim 1, characterized in that: The modified carbon fiber preparation method comprises the following steps: A1. The carbon fibers were washed with acetone and deionized water in sequence and then vacuum dried. The carbon fibers were then treated in a low-temperature oxygen plasma apparatus for 5 to 10 minutes. Dopamine hydrochloride was dissolved in Tris-HCl buffer and ultrasonically dispersed for 20 to 40 minutes. The treated carbon fibers were immersed in the solution and magnetically stirred at 25°C for 6 to 10 hours to form a polydopamine layer. A2, immersing the polydopamine-coated carbon fiber in an ethanol solution of 3-mercaptopropyltriethoxysilane, reacting at 50°C for 3-5 hours, centrifuging and washing, and then vacuum drying to obtain a surface mercaptan-modified carbon fiber; A3. Disperse nano-ZrO2 in toluene, add vinyltrimethoxysilane, and reflux at 110°C for 10-12 hours under nitrogen protection. Centrifuge, wash, and vacuum dry to obtain vinyl-modified nano-ZrO2. A4. Disperse the vinyl-modified nano ZrO2 in anhydrous ethanol, add polyvinyl pyrrolidone, and ultrasonically treat for 40 to 60 minutes. Then, immerse the carbon fiber obtained in A2 in the nano ZrO2 dispersion, deoxygenate it with nitrogen for 5 to 10 minutes, irradiate it under ultraviolet light for 10 to 20 minutes, centrifuge and wash it, and then vacuum dry it to obtain the modified carbon fiber.

4. The PEEK composite material with high wear resistance according to claim 4, characterized in that: In step A1, the mass ratio of dopamine hydrochloride to carbon fiber is 1:5-10.

5. The PEEK composite material with high wear resistance according to claim 4, characterized in that: In the step A4, the mass ratio of the vinyl-modified nano ZrO2 to the surface-sulfhydrylated carbon fiber is 1:10-20.

6. The PEEK composite material with high wear resistance according to claim 4, characterized in that: The ultraviolet light has a wavelength of 360-370 nm and a light intensity of 20-40 mW / cm 2 .

7. The PEEK composite material with high wear resistance according to claim 1, characterized in that: The modified Ti3C2T x The preparation method of MXene material includes the following steps: B1. Slowly add MAX phase Ti3AlC2 into HF and stir at 35℃ for 20-24h. Centrifuge and wash the acidic precipitate until the supernatant is neutral. Ultrasonicate in an ice bath and centrifuge repeatedly to collect the upper dispersion to obtain Ti3C2T x MXene dispersion; B2. Add graphene oxide to deionized water and ultrasonically disperse for 10 to 20 minutes to obtain graphene oxide dispersion. Then, x The MXene dispersion and graphene oxide dispersion were mixed and ultrasonic dispersion was continued for 20-40 min. The dispersion was freeze-dried and placed in a tube furnace. A mixture of NH3 and Ar was introduced and heated to 600 °C for 1-3 h to generate TiN / Ti3C2T x / N-rGO heterostructure; B3, TiN / Ti3C2T x The N-rGO heterostructure was ultrasonically mixed with ZIF-67 in methanol for 1-2 h, dried in vacuo at 60 °C, placed in an Ar atmosphere, and heated to 900 °C at a heating rate of 5 °C / min and annealed for 1 h to obtain the modified Ti3C2T x MXene materials.

8. The PEEK composite material with high wear resistance according to claim 7, characterized in that: In step B2, graphene oxide and Ti3C2T x The mass ratio of MXene is 1:1 to 1.2, and NH3 and Ar are mixed in a volume ratio of 1:

4.

9. The PEEK composite material with high wear resistance according to claim 7, characterized in that: In step B3, TiN / Ti3C2T x The mass ratio of / N-rGO heterostructure to ZIF-67 is 2-4:1, and the modified Ti3C2T x The Co loading amount in MXene material is 1-1.2 wt%.

10. The method for preparing a PEEK composite material with high wear resistance according to any one of claims 1 to 9, characterized in that: The following steps are included: (1) PEEK resin and PTFE resin were vacuum dried at 120℃ for 4-6h, and the modified Ti3C2T x The MXene material and PTFE oligomer were ultrasonically mixed in ethanol for 40-60 min, filtered and vacuum dried to obtain pretreated modified Ti3C2T x MXene materials; (2) Then PEEK resin, PTFE resin, modified carbon fiber and pretreated modified Ti3C2T x MXene material was added to the extruder, and the extruder temperature was zoned: zone 1 340°C, zone 2 360°C, zone 3 380°C, zone 4 380°C; (3) applying a horizontal magnetic field in the third zone of the extruder barrel with a magnetic field intensity of 0.5 T, a screw speed of 150 rpm, and a residence time of 2 to 4 min, and water-cooling and pelletizing the extruded strips to obtain composite particles; (4) The composite particles are placed in a mold, preheated at 385° C. for 8 to 10 minutes, maintained at a pressure of 20 MPa for 12 to 15 minutes, quenched in cold water to set the shape, and finally annealed at 200° C. for 1 to 3 hours to obtain the PEEK composite material with high wear resistance.

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