Self-repairing wear-resistant coating, preparation method and scalpel applying self-repairing wear-resistant coating

Abstract

The invention relates to the field of scalpel coatings, in particular to a self-repairing wear-resistant coating, a preparation method and a scalpel applying the self-repairing wear-resistant coating. The self-repairing wear-resistant coating comprises a vapor deposition layer and a self-repairing coating layer which are sequentially coated from inside to outside, the self-repairing coating layer is formed by drying and curing self-repairing coating liquid, and the wear-resistant and self-repairing dual functions are achieved through the synergistic effect of the vapor deposition layer and the self-repairing coating layer. The vapor deposition layer serves as a bottom layer and provides basic hardness and wear resistance, and the self-repairing coating layer is formed by curing a coating liquid and comprises poly (N-isopropylacrylamide) microgel, an antibacterial agent and self-repairing particles. The self-repairing particles realize microscopic repairing through chemical bond recombination when the coating is damaged, and the integrity of the coating is maintained. According to the double-layer structure, physical wear resistance and chemical self-repairing are combined, so that the service life of the surgical knife is remarkably prolonged, and the pollution risk in an operation is reduced.

Description

Technical Field

[0001] The present application relates to the field of scalpel coatings, and in particular to a self-repairing wear-resistant coating, a preparation method, and a scalpel using the same. Background Art

[0002] Surgical tool coatings are specialized layers of material applied to the surface of surgical tools, adhered to the tool base through a specialized process. They play a vital role in modern medicine. On the one hand, coatings significantly improve the wear resistance of surgical tools, reducing wear during use, thereby extending tool life and reducing medical costs. On the other hand, coatings can also improve the tool's surface properties, such as reducing the coefficient of friction, making surgical procedures smoother, minimizing tissue damage, and improving surgical precision and safety.

[0003] In the medical field, surgical tool coatings are increasingly used. From routine surgical procedures to delicate minimally invasive surgeries, coated tools demonstrate unique advantages. With the continuous advancement of medical technology, the performance requirements for surgical tools are becoming increasingly demanding. Surgical tool coating technology is also constantly evolving and innovating to meet this growing medical need.

[0004] In response to the above-mentioned prior art, the inventors found that the existing surgical tool coatings have obvious problems in terms of wear resistance. The hardness and wear resistance of some coating materials themselves are poor, and it is difficult to withstand the frequent friction and cutting during surgery. At the same time, the bonding strength between the coating and the tool substrate is not enough, and the coating is prone to peeling during use. At the same time, the self-repair ability of traditional surgical tools is limited. Most of the existing self-repairing materials can only work under specific conditions, and the repair effect is limited. It is difficult to completely restore the original performance of the coating. The self-repair process often takes a long time and cannot meet the immediate needs of the operation. Summary of the Invention

[0005] In order to improve the above technical problems, the present application provides a self-repairing wear-resistant coating and a preparation method thereof.

[0006] In a first aspect, the present application provides a self-repairing wear-resistant coating, which adopts the following technical solution: A self-repairing wear-resistant coating, comprising a vapor deposition layer and a self-repairing coating layer sequentially coated from the inside out, wherein the self-repairing coating layer is formed by drying and solidifying a self-repairing coating liquid, wherein the self-repairing coating liquid comprises the following substances in parts by weight: 45-60 parts of poly (N-isopropylacrylamide) microgel; 3-8 parts of antibacterial agent; 8-15 parts of self-repairing particles.

[0007] Through the above technical solution, the present application realizes the dual functions of wear resistance and self-repair through the synergistic effect of the vapor deposition layer and the self-repairing coating layer. The vapor deposition layer serves as the bottom layer, providing basic hardness and wear resistance, while the self-repairing coating layer is formed by solidification of the coating liquid, and comprises poly N-isopropylacrylamide microgel, antibacterial agent and self-repairing particles. The microgel has temperature-responsive characteristics. When the tool is locally heated due to friction, its molecular chain segments shrink or stretch, which can relieve stress concentration. At the same time, the interpenetrating network structure of the microgel can absorb impact energy and enhance the toughness of the coating. The antibacterial agent directly inhibits bacterial growth and prevents intraoperative infection. When the coating is damaged, the self-repairing particles achieve microscopic repair through chemical bond recombination to maintain the integrity of the coating. This double-layer structure significantly extends the service life of surgical tools and reduces the risk of intraoperative contamination through the combination of physical wear resistance and chemical self-repair.

[0008] Furthermore, the antibacterial agent is chitosan-coated nanosilver particles with a particle size of 20 to 50 nm.

[0009] Through the above technical solution, the present application defines the antibacterial agent as chitosan-coated nanosilver particles, due to the synergistic effect of the broad-spectrum antibacterial activity of nanosilver and the biocompatibility of chitosan. Nanosilver destroys bacterial cell membranes and interferes with DNA replication by releasing Ag⁺ ions, but due to its high surface energy, it is easy to agglomerate. Chitosan coating can stabilize the dispersion of nanosilver and achieve sustained release, thereby prolonging the antibacterial effect. Nanosilver with a particle size controlled at 20-50 nm has a high specific surface area and penetration ability, and can effectively kill Gram-positive / negative bacteria and fungi. At the same time, chitosan itself has antibacterial and film-forming properties, further strengthening the biological barrier function of the coating, thereby avoiding the short-term failure problem of traditional silver ion coatings caused by rapid release.

[0010] Furthermore, the self-repairing particles are polyurethane elastomer particles containing dynamic disulfide bonds.

[0011] Through the above-mentioned technical solution, this application utilizes polyurethane elastomer particles containing dynamic disulfide bonds in self-healing particles. The self-healing mechanism relies on the reversible breakage and recombination of dynamic covalent bonds. Disulfide bonds (—S—S—) break under external stress or heat to form thiol groups (—SH). When damage occurs, the thiol groups at the broken ends can reoxidize to form disulfide bonds, enabling autonomous repair of the molecular chain. The polyurethane elastomer imparts high elasticity and toughness to the particles, enabling them to adapt to the deformation of surgical tools during the cutting process and dissipate stress through the continuous recombination of dynamic bonds. Compared to traditional physically filled self-healing materials, dynamic chemical bond repair does not require an external trigger, and the repair process can be repeated multiple times, making it particularly suitable for high-frequency surgical tools. Furthermore, the bioinertness of polyurethane avoids negative reactions between the coating and human tissue, meeting the biosafety requirements of medical devices.

[0012] Furthermore, the vapor deposition layer includes a Si3N4 nanowire network coating layer and a graphene aerogel layer filled on the surface of the Si3N4 nanowire network coating layer.

[0013] Through the above technical solution, the present application further refines the vapor-deposited layer into a composite structure of a Si3N4 nanowire network coating layer and a graphene aerogel layer. Si3N4 nanowires form a three-dimensional network skeleton through chemical vapor deposition. Its high hardness and wear resistance provide basic protection for the coating, and the staggered structure of the nanowires can effectively inhibit crack propagation. Graphene aerogel is filled in the gaps in the Si3N4 network, and its ultra-high specific surface area and conductivity are used to enhance the thermal conductivity of the coating to avoid local overheating. At the same time, the layered structure of graphene can further block the penetration of corrosive media. The synergistic effect of Si3N4 and graphene forms a "hard and soft" wear-resistant system: Si3N4 bears the main mechanical load, graphene reduces the friction coefficient through lubrication, and uses its high toughness to buffer impact. This composite structure enables the coating to maintain structural stability under extreme loads, and is suitable for the complex working conditions of high-precision surgical tools.

[0014] Furthermore, the Si3N4 nanowire network coating layer is prepared by electrophoretic deposition of a deposition solution, and the deposition solution includes the following substances in parts by weight: 1-5 parts of silazane powder; Polyacrylic acid 0.1-0.5 parts; 80-120 parts of ethanol solution.

[0015] Through the above-mentioned technical solution, this application utilizes electrophoretic deposition technology, where the deposition solution contains a silazane precursor, a polyacrylic acid dispersant, and an ethanol solvent. Silazane hydrolyzes in ethanol to form a Si—O—Si network, and polyacrylic acid stabilizes the nanoparticle dispersion through electrostatic interaction, preventing agglomeration. During the electrophoretic deposition process, the tool acts as the cathode, and the positively charged silazane hydrolysis products, driven by an electric field, are directionally deposited and condensed into a Si3N4 nanowire network. This method has the advantages of low-temperature film formation (avoiding thermal damage to the tool substrate), fast deposition rate, and controllable thickness. The carboxyl groups of polyacrylic acid can adjust the solution pH, optimize the nanowire growth direction, and form a uniform and dense network structure.

[0016] Furthermore, the graphene aerogel layer is prepared by vacuum impregnation of a graphene dispersion followed by in-situ reduction, wherein the graphene dispersion comprises the following substances in parts by weight: 0.1-0.5 parts of graphene oxide; 100-200 parts of reducing agent; 20-50 parts of polyacrylic acid; 500-800 parts of ammonia water.

[0017] Through the above technical solution, the present application uses vacuum impregnation and in-situ reduction of graphene oxide dispersion. In the GO dispersion, polyacrylic acid is adsorbed on the edge of the GO sheet as a surfactant to prevent stacking by electrostatic repulsion; ammonia adjusts the pH to alkaline, promotes the ionization of hydroxyl groups on the surface of the GO sheet, and enhances the dispersion stability. Vacuum impregnation allows the GO solution to fully penetrate the Si3N4 nanowire network, and then the GO is converted into graphene by thermal reduction or chemical reduction, while removing oxygen-containing groups and restoring conductivity. During the reduction process, the graphene sheets self-assemble to form a three-dimensional porous aerogel structure, whose high porosity not only reduces the coating density, but also provides an elastic buffer space. This process achieves a close composite of graphene and Si3N4 nanowires, and the elastic modulus of the aerogel complements the rigidity of Si3N4, significantly improving the fatigue resistance of the coating.

[0018] In a second aspect, the present application provides a method for preparing a self-repairing wear-resistant coating, which adopts the following technical solutions: A method for preparing a self-repairing wear-resistant coating comprises the following steps: Take the cutting tool and electrophoretically deposit a Si3N4 nanowire network coating on its surface. After the deposition is completed, place it in a graphene dispersion, vacuum immerse it, and heat it for reduction treatment. After the restoration is completed, the self-repairing coating liquid is sprayed and then dried and solidified to prepare a self-repairing wear-resistant coating.

[0019] Through the above technical solution, the present application first deposits a Si3N4 nanowire network by electrophoresis, then vacuum impregnates the graphene dispersion and reduces it to form an aerogel layer, and finally sprays the self-healing coating liquid for solidification. The key to the three-step process of electrophoretic deposition-vacuum impregnation-spraying lies in the optimization of the interface bonding between the layers. The rough surface of the Si3N4 nanowire enhances the mechanical interlocking with the graphene aerogel, and the hydrophobic surface of the graphene is conducive to the uniform spreading of the subsequent aqueous self-healing liquid. During the spraying process, the solvent of the self-healing coating liquid needs to be compatible with the lower layer to avoid dissolving or destroying the vapor deposited layer. During drying and solidification, the PNIPAM microgel is cross-linked with the polyurethane particles through hydrogen bonds to form an interpenetrating network that runs through the two phases, ensuring the integrity of the coating. This method takes into account both efficiency and precision, is suitable for large-scale production, and can customize the coating properties by adjusting parameters such as deposition time and impregnation pressure. A scalpel comprising any one of the above-mentioned self-repairing wear-resistant coatings.

[0020] In summary, this application has the following beneficial effects: First, the present application achieves the dual functions of wear resistance and self-repair through the synergistic effect of the vapor deposition layer and the self-repairing coating layer. The vapor deposition layer serves as the bottom layer, providing basic hardness and wear resistance, while the self-repairing coating layer is formed by solidification of the coating liquid, and comprises poly N-isopropylacrylamide microgel, antibacterial agent and self-repairing particles. The microgel has temperature-responsive properties. When the tool is locally heated due to friction, its molecular chain segments shrink or stretch, which can relieve stress concentration. At the same time, the interpenetrating network structure of the microgel can absorb impact energy and enhance the toughness of the coating. The antibacterial agent directly inhibits bacterial growth and prevents intraoperative infection. When the coating is damaged, the self-repairing particles achieve microscopic repair through chemical bond recombination to maintain the integrity of the coating. This double-layer structure significantly extends the service life of surgical tools and reduces the risk of intraoperative contamination through the combination of physical wear resistance and chemical self-repair.

[0021] Second, this application utilizes polyurethane elastomer particles containing dynamic disulfide bonds within the self-healing particles. The self-healing mechanism relies on the reversible breakage and recombination of dynamic covalent bonds. Disulfide bonds (—S—S—) break under external stress or heat to form thiol groups (—SH). When damage occurs, the thiol groups at the broken ends can reoxidize to form disulfide bonds, enabling autonomous repair of the molecular chain. The polyurethane elastomer imparts high elasticity and toughness to the particles, enabling them to adapt to the deformation of surgical tools during the cutting process and dissipate stress through the continuous recombination of dynamic bonds. Compared to traditional physically filled self-healing materials, dynamic chemical bond repair does not require an external trigger, and the repair process can be repeated multiple times, making it particularly suitable for high-frequency surgical tools. Furthermore, the bioinertness of polyurethane avoids negative reactions between the coating and human tissue, meeting the biosafety requirements of medical devices.

[0022] Third, the present application further refines the vapor-deposited layer into a composite structure of a Si3N4 nanowire network coating layer and a graphene aerogel layer. Si3N4 nanowires form a three-dimensional network skeleton through chemical vapor deposition. Their high hardness and wear resistance provide basic protection for the coating, and the staggered structure of the nanowires can effectively inhibit crack propagation. Graphene aerogel is filled in the gaps in the Si3N4 network, and its ultra-high specific surface area and electrical conductivity are used to enhance the thermal conductivity of the coating to avoid local overheating. At the same time, the layered structure of graphene can further block the penetration of corrosive media. The synergistic effect of Si3N4 and graphene forms a "hard and soft" wear-resistant system: Si3N4 bears the main mechanical load, graphene reduces the friction coefficient through lubrication, and uses its high toughness to buffer impact. This composite structure enables the coating to maintain structural stability under extreme loads, and is suitable for the complex working conditions of high-precision surgical tools. DETAILED DESCRIPTION

[0023] The present application is further described in detail below with reference to the embodiments.

[0024] Preparation Example 1 antimicrobial agents A 1% chitosan acetate solution and a 0.1 mol / L silver nitrate solution were mixed in a 5:1 volume ratio. Ascorbic acid was added as a reducing agent and stirred in a 50°C water bath for 2 hours to produce silver nanoparticles with a diameter of 20-50 nm. The mixture was then centrifuged at 1500 rpm for washing. The silver nanoparticles were then mixed with a 2% chitosan solution in a 1:3 mass ratio and ultrasonically treated for 30 minutes to obtain a colloidal solution. The solution was then freeze-dried in a vacuum, ground, and sieved to prepare the antibacterial agent.

[0025] Preparation Example 2 Self-repairing particles Polytetramethylenediol (molecular weight: 2000) and isophorone diisocyanate (molecular weight: 1:2) were mixed and reacted at 80°C under nitrogen for 3 hours. The resulting prepolymer was collected, and then 4,4'-dithiodiphenylamine and 1,4-butanediol chain extenders were added. The reaction was continued at 60°C until the NCO content was less than 0.1%. The product was dissolved in tetrahydrofuran and spray-dried at an inlet temperature of 120°C and an outlet temperature of 60°C to produce elastomer particles with a particle size of 5-20 μm.

[0026] Preparation Example 3 Self-repair coating liquid 1 45 kg of poly (N-isopropylacrylamide) microgel was dispersed in 200 kg of deionized water, and 3 kg of antibacterial agent was mixed and stirred for 1 hour. Finally, 8 kg of self-healing particles were added and stirred until the suspension was stable to prepare the self-healing coating liquid 1.

[0027] Preparation Example 4 Self-repair coating liquid 2 52 kg of poly (N-isopropylacrylamide) microgel was dispersed in 250 kg of deionized water, and 5 kg of antibacterial agent was mixed and stirred for 1 hour. Finally, 12 kg of self-healing particles were added and stirred until the suspension was stable to prepare the self-healing coating liquid 2.

[0028] Preparation Example 5 Self-repair coating liquid 3 60 kg of poly (N-isopropylacrylamide) microgel was dispersed in 300 kg of deionized water, and 8 kg of antibacterial agent was mixed and stirred for 1 hour. Finally, 15 kg of self-healing particles were added and stirred until the suspension was stable to prepare the self-healing coating liquid 3.

[0029] Preparation Example 6 Sedimentation liquid 1 1-5 kg ​​of silazane powder, 0.1-0.5 kg of polyacrylic acid and 80-120 kg of 75% by mass ethanol solution are mixed by stirring and ultrasonically dispersed to prepare a deposition solution 1.

[0030] Preparation Example 7 Sediment 2 1-5 kg ​​of silazane powder, 0.1-0.5 kg of polyacrylic acid and 80-120 kg of 75% by mass ethanol solution are mixed by stirring and ultrasonically dispersed to prepare a deposition solution 2.

[0031] Preparation Example 8 Sedimentation liquid 3 1-5 kg ​​of silazane powder, 0.1-0.5 kg of polyacrylic acid and 80-120 kg of 75% by mass ethanol solution are mixed by stirring and ultrasonically dispersed to prepare a deposition solution 3.

[0032] Preparation Example 9 Graphene dispersion 1 0.1 g of graphene oxide, 100 g of ascorbic acid (a reducing agent), 20 g of polyacrylic acid, and 500 g of 8% by mass ammonia water were mixed and stirred to prepare a graphene dispersion 1.

[0033] Preparation Example 10 Graphene dispersion 2 0.3 g of graphene oxide, 150 g of ascorbic acid (a reducing agent), 35 g of polyacrylic acid, and 650 g of 8% by mass ammonia water were mixed and stirred to prepare a graphene dispersion 2.

[0034] Preparation Example 11 Graphene dispersion 3 0.5 g of graphene oxide, 200 g of ascorbic acid (a reducing agent), 50 g of polyacrylic acid, and 800 g of 8% by mass ammonia water were mixed and stirred to prepare a graphene dispersion 3.

[0035] Example Example 1 A self-repairing wear-resistant coating comprises a vapor deposition layer and a self-repairing coating layer which are sequentially coated from the inside to the outside.

[0036] A method for preparing a self-repairing wear-resistant coating comprises the following steps: Preparation of vapor deposition layer: The surface of the scalpel to be coated was sandblasted with 50 μm aluminum oxide sand to increase the roughness, and ultrasonically cleaned with ethanol-acetone mixture before deposition. After adding deposition solution 1 to the electrophoresis tank, the temperature was maintained at 25 ± 2 ° C. The scalpel was used as the cathode and the platinum sheet was used as the anode. The voltage was 50 V and the current density was 2 mA / cm 2The tool was then immersed in graphene dispersion 1 and maintained at a vacuum of 0.1 MPa for 1 hour to allow the dispersion to fully penetrate the gaps between the nanowires. The temperature was then raised to 120°C at a heating rate of 5°C / min to in-situ reduce the graphene oxide, ultimately producing a vapor-deposited layer. Preparation of self-repairing coating: The self-repairing coating liquid is evenly sprayed on the surface of the tool coated with the vapor deposition layer through a high-pressure spray gun. The spraying pressure is controlled at 0.3~0.5MPa and the spray distance is 15~20 cm to form a wet film with a thickness of 20~50 μm. It is then dried and cured in a 60℃ oven for 2h to prepare a self-repairing coating, which can be used to prepare a self-repairing wear-resistant coating.

[0037] Example 2 A self-repairing wear-resistant coating comprises a vapor deposition layer and a self-repairing coating layer which are sequentially coated from the inside to the outside.

[0038] A method for preparing a self-repairing wear-resistant coating comprises the following steps: Preparation of vapor deposition layer: The surface of the scalpel to be coated was sandblasted with 50 μm aluminum oxide sand to increase the roughness, and ultrasonically cleaned with ethanol-acetone mixture before deposition. After adding deposition solution 2 to the electrophoresis tank, the temperature was maintained at 25 ± 2 °C. The scalpel was used as the cathode and the platinum sheet was used as the anode. The voltage was 50 V and the current density was 2 mA / cm 2 The tool was then immersed in graphene dispersion 1 and maintained at a vacuum of 0.1 MPa for 1 hour to allow the dispersion to fully penetrate the gaps between the nanowires. The temperature was then raised to 120°C at a heating rate of 5°C / min to in-situ reduce the graphene oxide, ultimately producing a vapor-deposited layer. Preparation of self-repairing coating: The self-repairing coating liquid is evenly sprayed on the surface of the tool coated with the vapor deposition layer through a high-pressure spray gun. The spraying pressure is controlled at 0.3~0.5MPa and the spray distance is 15~20 cm to form a wet film with a thickness of 20~50 μm. It is then dried and cured in a 60℃ oven for 2h to prepare a self-repairing coating, which can be used to prepare a self-repairing wear-resistant coating.

[0039] Example 3 A self-repairing wear-resistant coating comprises a vapor deposition layer and a self-repairing coating layer which are sequentially coated from the inside to the outside.

[0040] A method for preparing a self-repairing wear-resistant coating comprises the following steps: Preparation of vapor deposition layer: The surface of the scalpel to be coated was sandblasted with 50 μm aluminum oxide sand to increase the roughness, and ultrasonically cleaned with ethanol-acetone mixture before deposition. After adding deposition solution 3 to the electrophoresis tank, the temperature was maintained at 25 ± 2 °C. The scalpel was used as the cathode and the platinum sheet was used as the anode. The voltage was 50 V and the current density was 2 mA / cm 2 The tool was then immersed in graphene dispersion 1 and maintained at a vacuum of 0.1 MPa for 1 hour to allow the dispersion to fully penetrate the gaps between the nanowires. The temperature was then raised to 120°C at a heating rate of 5°C / min to in-situ reduce the graphene oxide, ultimately producing a vapor-deposited layer. Preparation of self-repairing coating: The self-repairing coating liquid is evenly sprayed on the surface of the tool coated with the vapor deposition layer through a high-pressure spray gun. The spraying pressure is controlled at 0.3~0.5MPa and the spray distance is 15~20 cm to form a wet film with a thickness of 20~50 μm. It is then dried and cured in a 60℃ oven for 2h to prepare a self-repairing coating, which can be used to prepare a self-repairing wear-resistant coating.

[0041] Example 4 A self-repairing wear-resistant coating comprises a vapor deposition layer and a self-repairing coating layer which are sequentially coated from the inside to the outside.

[0042] A method for preparing a self-repairing wear-resistant coating comprises the following steps: Preparation of vapor deposition layer: The surface of the scalpel to be coated was sandblasted with 50 μm aluminum oxide sand to increase the roughness, and ultrasonically cleaned with ethanol-acetone mixture before deposition. After adding deposition solution 2 to the electrophoresis tank, the temperature was maintained at 25 ± 2 °C. The scalpel was used as the cathode and the platinum sheet was used as the anode. The voltage was 50 V and the current density was 2 mA / cm 2 The tool was then immersed in graphene dispersion 2 and maintained at a vacuum of 0.1 MPa for 1 hour to allow the dispersion to fully penetrate the gaps between the nanowires. The temperature was then raised to 120°C at a heating rate of 5°C / min to in-situ reduce the graphene oxide, ultimately producing a vapor-deposited layer. Preparation of self-repairing coating: The self-repairing coating liquid is evenly sprayed on the surface of the tool coated with the vapor deposition layer through a high-pressure spray gun. The spraying pressure is controlled at 0.3~0.5MPa and the spray distance is 15~20 cm to form a wet film with a thickness of 20~50 μm. It is then dried and cured in a 60℃ oven for 2h to prepare a self-repairing coating, which can be used to prepare a self-repairing wear-resistant coating.

[0043] Example 5 A self-repairing wear-resistant coating comprises a vapor deposition layer and a self-repairing coating layer which are sequentially coated from the inside to the outside.

[0044] A method for preparing a self-repairing wear-resistant coating comprises the following steps: Preparation of vapor deposition layer: The surface of the scalpel to be coated was sandblasted with 50 μm aluminum oxide sand to increase the roughness, and ultrasonically cleaned with ethanol-acetone mixture before deposition. After adding deposition solution 2 to the electrophoresis tank, the temperature was maintained at 25 ± 2 °C. The scalpel was used as the cathode and the platinum sheet was used as the anode. The voltage was 50 V and the current density was 2 mA / cm 2 The tool was then immersed in graphene dispersion 3 and maintained at a vacuum of 0.1 MPa for 1 hour to allow the dispersion to fully penetrate the gaps between the nanowires. The temperature was then raised to 120°C at a heating rate of 5°C / min to in-situ reduce the graphene oxide, ultimately producing a vapor-deposited layer. Preparation of self-repairing coating: The self-repairing coating liquid is evenly sprayed on the surface of the tool coated with the vapor deposition layer through a high-pressure spray gun. The spraying pressure is controlled at 0.3~0.5MPa and the spray distance is 15~20 cm to form a wet film with a thickness of 20~50 μm. It is then dried and cured in a 60℃ oven for 2h to prepare a self-repairing coating, which can be used to prepare a self-repairing wear-resistant coating.

[0045] Comparative Example 1 A self-repairing wear-resistant coating, compared with Example 1, without adding self-repairing particles.

[0046] Comparative Example 2 A self-repairing wear-resistant coating, compared with Example 1, does not have a self-repairing coating layer.

[0047] Performance testing 1. Wear resistance test: ASTM G65 grinding wheel wear test: 1. Fix the coating sample (size 25×75 mm) in the fixture with the grinding wheel in vertical contact with the sample surface.

[0048] 2. Start the grinding wheel and load it to 10 N. Continue grinding for 1000 revolutions (approximately 5 minutes).

[0049] 3. Use an electronic balance (accuracy 0.1 mg) to measure the mass difference before and after wear and calculate the wear rate: Each group of samples was tested 3 times and the average value was taken.

[0050] 2. Self-repair efficiency test 1. Use a micro scratch tester to create scratches with a depth of 2 μm and a width of 10 μm on the coating surface.

[0051] 2. Immerse the sample in 37°C saline (pH 7.4) for 24 hours to simulate the in vivo environment.

[0052] 3. Test using laser confocal microscopy and calculate the healing rate: Healing rate = (1- d final / d initial ) × 100% in, d initial : initial scratch depth, d final : Depth after healing.

[0053] 3. Coating adhesion test: Test according to standard ASTM D3359-17.

[0054] The test results are shown in Table 1 below: Table 1 Performance test table

[0055] Comparison of Examples 1-5 with Comparative Examples 1 and 2 reveals that the present invention's self-healing particles achieve microscopic repair through chemical bond reorganization when the coating is damaged, maintaining coating integrity. This dual-layer structure significantly extends the life of surgical tools and reduces the risk of intraoperative contamination by combining physical wear resistance with chemical self-healing.

[0056] At the same time, the present application further refines the vapor-deposited layer into a composite structure of a Si3N4 nanowire network coating layer and a graphene aerogel layer. Si3N4 nanowires form a three-dimensional network skeleton through chemical vapor deposition. Their high hardness and wear resistance provide basic protection for the coating, and the staggered structure of the nanowires can effectively inhibit crack propagation. Graphene aerogel fills the gaps in the Si3N4 network, and uses its ultra-high specific surface area and conductivity to enhance the thermal conductivity of the coating to avoid local overheating. At the same time, the layered structure of graphene can further block the penetration of corrosive media. The synergistic effect of Si3N4 and graphene forms a "hard and soft" wear-resistant system: Si3N4 bears the main mechanical load, graphene reduces the friction coefficient through lubrication, and uses its high toughness to buffer impact. This composite structure enables the coating to maintain structural stability under extreme loads, and is suitable for the complex working conditions of high-precision surgical tools.

[0057] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make non-creative modifications to the present embodiment as needed, but as long as they are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. A self-repairing wear-resistant coating, characterized in that: It includes a vapor deposition layer and a self-repairing coating layer sequentially coated from the inside to the outside, wherein the self-repairing coating layer is formed by drying and solidifying a self-repairing coating liquid, and the self-repairing coating liquid includes the following substances in parts by weight: 45-60 parts of poly (N-isopropylacrylamide) microgel; 3-8 parts of antibacterial agent; 8-15 parts of self-repairing particles.

2. A self-repairing wear-resistant coating according to claim 1, characterized in that: The antibacterial agent is chitosan-wrapped nanosilver particles with a particle size of 20 to 50 nm.

3. The self-repairing wear-resistant coating according to claim 1, characterized in that: The self-repairing particles are polyurethane elastomer particles containing dynamic disulfide bonds.

4. The self-repairing wear-resistant coating according to claim 1, characterized in that: The vapor deposition layer includes a Si3N4 nanowire network coating layer and a graphene aerogel layer filled on the surface of the Si3N4 nanowire network coating layer.

5. The self-repairing wear-resistant coating according to claim 4, characterized in that: The Si3N4 nanowire network coating layer is prepared by electrophoretic deposition of a deposition solution, wherein the deposition solution comprises the following substances in parts by weight: 1-5 parts of silazane powder; Polyacrylic acid 0.1-0.5 parts; 80-120 parts of ethanol solution.

6. The self-repairing wear-resistant coating according to claim 1, characterized in that: The graphene aerogel layer is prepared by vacuum impregnation of a graphene dispersion followed by in-situ reduction, wherein the graphene dispersion comprises the following substances in parts by weight: 0.1-0.5 parts of graphene oxide; 100-200 parts of reducing agent; 20-50 parts of polyacrylic acid; 500-800 parts of ammonia water.

7. The method for preparing a self-repairing wear-resistant coating according to any one of claims 1 to 6, characterized in that: The method comprises the following preparation steps: Take the cutting tool and electrophoretically deposit a Si3N4 nanowire network coating on its surface. After the deposition is completed, place it in a graphene dispersion, vacuum immerse it, and heat it for reduction treatment. After the restoration is completed, the self-repairing coating liquid is sprayed and then dried and solidified to prepare a self-repairing wear-resistant coating.

8. A surgical knife comprising the self-repairing wear-resistant coating according to any one of claims 1 to 6.

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