A fluorinated diamond nanosheet anti-corrosion coating and its preparation method

Abstract

This invention discloses a fluorinated diamond nanosheet anti-corrosion coating and its preparation method. The method includes: mixing a diamond nanosheet dispersion with a perfluorosilane coupling agent solution to obtain a mixed solution; adding an alkaline catalyst to the mixed solution to carry out a reaction, obtaining a fluorinated diamond nanosheet polymer; melting the fluorinated diamond nanosheet polymer and applying it to a substrate, followed by cooling and curing. This invention designs a fluorinated diamond nanosheet anti-corrosion coating with self-healing properties through a simple fluorination treatment of diamond nanosheets. This coating possesses a sensitive temperature response mechanism; when the coating suffers large-area damage, it can self-heal with simple heating treatment. The low-temperature curing characteristic also enables the coating to withstand low-temperature conditions. The addition of nanodiamond sheets can further block the erosion of corrosive media and improve the anti-corrosion ability of the coating.

Description

Technical Field

[0001] This invention relates to the fields of coating technology and anti-corrosion technology, and in particular to a fluorinated diamond nanosheet anti-corrosion coating and its preparation method. Background Technology

[0002] In modern industrial production, metallic materials are widely used in various industries. However, metallic materials are easily corroded by corrosive media during use, which not only affects their service life but also seriously impacts their performance. Therefore, metal corrosion prevention has always been an important issue in industrial production.

[0003] Currently, existing corrosion prevention methods mainly fall into three categories: physical corrosion prevention, chemical corrosion prevention, and biological corrosion prevention. Among them, biological corrosion prevention mainly uses biological means to prevent the corrosion of metal materials. Common methods include microbial corrosion prevention and biological preservatives. The advantage of biological corrosion prevention is that it is environmentally friendly and non-toxic, but the disadvantage is that it is greatly affected by environmental factors and its application scenarios are limited.

[0004] Chemical corrosion protection uses chemical methods to prevent the corrosion of metallic materials. Common methods include corrosion inhibitors and corrosion preservatives. The advantage of chemical corrosion protection is that it has a good anti-corrosion effect and can effectively inhibit the corrosion of materials. However, the disadvantage is that it has a greater impact on the environment and its application scenarios are limited.

[0005] Physical corrosion protection primarily prevents material corrosion through physical means. Common methods include coating corrosion protection, cathodic protection, and anodic protection. Cathodic and anodic protection offer high corrosion protection efficiency, but their high maintenance costs may limit their practical application due to cost constraints. Among physical corrosion protection methods, coating corrosion protection is currently the most commonly used. Its advantages include simple operation and obvious effects, but its disadvantage is that the coating may crack due to physical impact or over time, losing its anti-corrosion effect.

[0006] In recent years, self-healing anti-corrosion coatings have become a focus of attention. The advantage of anti-corrosion coatings is that they can automatically repair damage to the coating with minimal external stimulation or even without any intervention. This solves the problem of anti-corrosion materials being limited by the environment and the problem of traditional anti-corrosion coatings losing their anti-corrosion effect due to damage. In practical applications, this can greatly improve anti-corrosion efficiency and reduce maintenance costs.

[0007] Patent document CN105238211B discloses a method for preparing a self-healing coating material and its application. This coating material includes an inner repair layer and an outer surface layer. Urea-formaldehyde resin-encapsulated epoxy resin microcapsules (EP-UF microcapsules) are added to the repair layer to provide an epoxy resin (EP) repair agent. The repair agent repairs damage by interacting with a curing agent in the surface layer. However, the preparation method of this coating is relatively complex, the repair speed is not fast enough, and corrosive media continuously penetrate into the coating during the repair process, causing irreversible corrosion of the metal substrate before the coating is fully repaired.

[0008] Furthermore, current research has found that existing anti-corrosion coatings, due to issues with their repair mechanisms, struggle to achieve large-area repair effects and are also ineffective in protecting against the impact of low-temperature environments. Summary of the Invention

[0009] To address the shortcomings of existing technologies, this invention provides a method for preparing a fluorinated diamond nanosheet anti-corrosion coating. This method is simple; by subjecting diamond nanosheets to a simple fluorination treatment, a coating with a sensitive temperature response mechanism, high damage repair capability, and anti-corrosion effect can be obtained.

[0010] A method for preparing a fluorinated diamond nanosheet anti-corrosion coating includes the following steps:

[0011] (1) Disperse diamond nanosheets in deionized water to obtain a diamond nanosheet dispersion; dissolve a perfluorosilane coupling agent in an organic solvent to obtain a perfluorosilane coupling agent solution; mix the diamond nanosheet dispersion with the perfluorosilane coupling agent solution to obtain a mixed solution;

[0012] (2) Add an alkaline catalyst to the mixed solution obtained in step (1) and react to obtain fluorinated diamond nanosheet polymer;

[0013] (3) The fluorinated diamond nanosheet polymer obtained in step (2) is melted and coated onto the substrate, and then cooled and cured to obtain the fluorinated diamond nanosheet anti-corrosion coating.

[0014] This invention uses diamond nanosheets and perfluorosilane coupling agents as raw materials. The surface of diamond nanosheets is rich in hydroxyl groups, while the perfluorosilane coupling agent can undergo a hydrolysis reaction, thereby undergoing a condensation reaction with the hydroxyl groups on the surface of the diamond nanosheets. At the same time, the addition of an alkaline catalyst can not only accelerate this reaction, but also cause the perfluorosilane coupling agent to undergo self-polymerization. That is, the entire reaction process includes both the grafting reaction between the silane coupling agent and the diamond nanosheets and the self-polymerization reaction of the silane coupling agent itself, so that the diamond nanosheets can be encapsulated by the silane coupling agent self-polymer.

[0015] The reactant selected in this invention is a perfluorosilane coupling agent. This type of silane coupling agent contains a large amount of fluorine, resulting in a coating with low surface energy and good hydrophobic properties. It can effectively isolate corrosive agents such as water and oxygen in the early stages of corrosion. As corrosion progresses and corrosive agents penetrate the coating, the grafted diamond nanosheets exhibit a disordered, maze-like arrangement within the coating, further prolonging the erosion process and enhancing the coating's anti-corrosion performance. The coating possesses self-healing capabilities because when the temperature exceeds its glass transition temperature, the macromolecular chains begin to move, and the material enters a fluid state. Due to the height difference between the damaged and intact areas of the coating, the coating gradually flows towards the damaged area, ultimately achieving a self-healing effect.

[0016] Preferably, in step (1), the diamond nanosheets have a diameter of 60-300 nm and a thickness of 10-30 nm. Since diamonds of this size are two-dimensional nanosheets, these two-dimensional diamond nanosheets in the prepared anti-corrosion coating can play a good barrier effect in the coating, prolong the erosion process of corrosive agents, and further enhance the anti-corrosion performance of the coating.

[0017] Preferably, in step (1), diamond nanosheets are dispersed in deionized water and ultrasonically treated to obtain a diamond nanosheet dispersion. Ultrasonic treatment can make the diamond nanosheets more uniformly dispersed in deionized water.

[0018] Preferably, the ultrasonic treatment is performed at a temperature of 40-80℃, a power of 400-700W, and a time of 0.5-2h.

[0019] Preferably, in step (1), the concentration of the diamond nanosheet dispersion is 30-80 mg / mL.

[0020] Preferably, in step (1), the perfluorosilane coupling agent includes at least one of the following: triethoxy-1H,1H,2H,2H-nonafluorohexylsilane, triethoxy-1H,1H,2H,2H-tridecyl-N-octylsilane, 1H,1H,2H,2H-perfluorodecyltriethoxysilane, 1H,1H,2H,2H-perfluorooctyltrichlorosilane, or 1H,1H,2H,2H-perfluorodecyltrichlorosilane. In these silane coupling agents, the H atoms in the main chain are replaced by F atoms, which maintains the characteristics of silane coupling agents while having a low surface energy. Coatings prepared using this type of silane coupling agent exhibit good hydrophobic properties and can enhance the anti-corrosion performance of the coating.

[0021] Preferably, in step (1), the concentration of the perfluorosilane coupling agent solution is 3-15 mg / ml.

[0022] Preferably, in step (1), the volume ratio of the diamond nanosheet dispersion to the perfluorosilane coupling agent solution is 1:10-15.

[0023] Preferably, in step (2), the alkaline catalyst includes at least one of sodium hydroxide, ammonia, trimethylamine, or tetrahydropyrimidine. This invention adjusts the pH of the mixed solution to 9-12 by adding an alkaline catalyst, which accelerates the reaction rate between the perfluorosilane coupling agent and diamond nanosheets, while simultaneously promoting the self-polymerization of the perfluorosilane coupling agent itself.

[0024] Preferably, in step (2), the reaction temperature is 25-60℃ and the time is 12-48h.

[0025] Preferably, in step (3), the melting temperature of the fluorinated diamond nanosheet polymer is 50-120℃.

[0026] Preferably, in step (3), the substrate includes carbon steel substrate, titanium alloy substrate, glass substrate or polytetrafluoroethylene substrate, etc.

[0027] Preferably, in step (3), the curing temperature is -10℃ to 20℃ and the curing time is 0 to 48h.

[0028] This invention also provides a fluorinated diamond nanosheet anti-corrosion coating prepared by the aforementioned method. The anti-corrosion coating of this invention exhibits excellent damage repair and anti-corrosion effects, and possesses a unique temperature response mechanism, effectively protecting metallic materials from corrosion in low-temperature environments.

[0029] Preferably, the fluorinated diamond nanosheet anti-corrosion coating achieves self-healing function through heat treatment.

[0030] Preferably, the temperature of the heat treatment is 60-150℃.

[0031] Preferably, the fluorinated diamond nanosheet anti-corrosion coating can be used in an environment with a temperature range of -70 to 27°C.

[0032] Compared with the prior art, the present invention has at least the following beneficial effects:

[0033] The fluorinated diamond nanosheet anti-corrosion coating of this invention is prepared by simple fluorination of diamond nanosheets under catalytic conditions, resulting in a temperature-responsive, self-healing anti-corrosion coating (high-temperature melting, low-temperature curing). This allows for repair of coating damage through simple heat treatment. The coating itself has a certain degree of adhesion and can be easily applied to metal substrates without the aid of additional adhesives. Simultaneously, the fluorination treatment reduces the surface energy of the coating, giving it a certain degree of hydrophobic and oleophobic properties, thus providing excellent anti-corrosion performance. Furthermore, the random dispersion of diamond nanosheets within the coating further blocks corrosive media, enhancing the coating's anti-corrosion effect. The unique temperature responsiveness also allows the coating to provide good protection in low-temperature environments, effectively protecting metals and other materials from low-temperature corrosion.

[0034] The above description is merely an overview of the technical solution of the present invention. In order to enable those skilled in the art to better understand the technical means of this application and to implement it in accordance with the contents of the specification, the preferred embodiments of the present invention are described below in conjunction with detailed drawings. Attached Figure Description

[0035] Figure 1 This is the infrared spectrum of the fluorinated diamond nanosheets from Example 1.

[0036] Figure 2 This is the Raman spectrum of the fluorinated diamond nanosheets from Example 1.

[0037] Figure 3 This is the XRD pattern of the fluorinated diamond nanosheets from Example 1.

[0038] Figure 4 This is a TGA image of the fluorinated diamond nanosheets from Example 1.

[0039] Figure 5 This is a transmission electron microscope (TEM) image of the fluorinated diamond nanosheets from Example 1.

[0040] Figure 6 This is the DSC curve of the fluorinated diamond nanosheets from Example 1.

[0041] Figure 7These are optical photographs and 3D contour maps of the fluorinated diamond nanosheet anti-corrosion coating before and after self-healing damage in Example 2. Figure a is the initial optical photograph of the coating, and the initial 3D contour map of the coating is shown below Figure a. Figure b is the optical photograph of the damaged coating, and the 3D contour map of the damaged coating is shown below Figure b. Figures ch are optical photographs of the coating after 10 min, 20 min, 30 min, 40 min, 50 min, and 60 min of repair, respectively, and the 3D contour maps of the coating after 10 min, 20 min, 30 min, 40 min, 50 min, and 60 min of repair are shown below Figure ch.

[0042] Figure 8 a- Figure 8 b represents the curves showing the change in cross-sectional profile of the damaged diamond nanosheet anti-corrosion coating with healing time, and the curves showing the change in maximum volume and depth of the damaged diamond nanosheet anti-corrosion coating with healing time, respectively, in Example 2.

[0043] Figure 9 a1- Figure 9 a3 are Nyquist plots, Bode plots, and Tafel curves of the steel plate coated with fluorinated diamond nanosheet anti-corrosion coating and the pure Q235 steel plate in Example 3 before and after self-healing.

[0044] Figure 10 a1- Figure 10 a3 are the Nyquist plot, Bode plot, and Tafel curve of the steel plate coated with fluorinated diamond nanosheet anti-corrosion coating in Example 4 after being placed at room temperature and -64℃ for 15 hours, respectively.

[0045] Figure 11 a1- Figure 11 a3 are scanning electron microscope (SEM) images, elemental selection area distribution (SID) maps, and atomic force microscope (AFM) surface roughness maps of the pure Q235 steel plate after immersion in 3.5 wt% NaCl solution for 35 days, respectively.

[0046] Figure 12 b1- Figure 12 b3 are scanning electron microscope (SEM) images, elemental selection area distribution (SID) maps, and atomic force microscope (AFM) surface roughness maps of the steel plate coated with fluorinated diamond nanosheets for corrosion protection in Example 5 after immersion in 3.5% NaCl solution for 35 days.

[0047] Figure 13 This is the ultraviolet spectrum of the soaking solution collected after immersing a steel plate coated with fluorinated diamond nanosheets and a pure Q235 steel plate in a 3.5wt% NaCl solution for 35 days in Example 5. Detailed Implementation

[0048] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and therefore the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0049] In the embodiments of the present invention, diamond nanosheets and fluorinated diamond nanosheets were characterized by Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA), and transmission electron microscopy (TEM).

[0050] In the accompanying drawings and embodiments of this invention, DN represents diamond nanosheets, F-DN represents fluorinated diamond nanosheets, PFDTES represents perfluorosilane coupling agent, Q235 represents Q235 steel plate, and F-DN Coating represents fluorinated diamond nanosheet coating.

[0051] Example 1

[0052] This embodiment describes the specific process for preparing a fluorinated diamond nanosheet anti-corrosion coating on Q235 steel plate, including the following steps:

[0053] (1) Select a Q235 steel plate sample (specification: 20×20×3mm), and clean it ultrasonically in ethanol and petroleum ether for 30 minutes each, repeating 2-3 times. After cleaning, dry it with nitrogen for later use.

[0054] (2) Disperse 0.5g of diamond nanosheets in 10mL of deionized water and sonicate (550w power, 30min time) to form a uniform dispersion, and obtain a diamond nanosheet dispersion with a concentration of 50mg / ml.

[0055] (3) Dissolve 1.5g of 1H,1H,2H,2H-perfluorodecyltriethoxysilane in 100mL of anhydrous ethanol to form a homogeneous solution, and obtain a perfluorosilane coupling agent solution with a concentration of 15mg / ml.

[0056] (4) Mix 10 mL of diamond nanosheet dispersion with 100 mL of the solution obtained in step (3) to obtain a mixed solution.

[0057] (5) Add ammonia to the mixed solution obtained in step (4) to adjust the pH of the mixed solution to 10, and react at 25°C for 24 hours to obtain fluorinated diamond nanosheet polymer.

[0058] (6) The fluorinated diamond nanosheet polymer obtained in step (5) is melted at 80°C and coated onto a Q235 steel plate. Then it is cooled and cured at 4°C for 24 hours to obtain a diamond nanosheet anti-corrosion coating.

[0059] The infrared spectrum of the fluorinated diamond nanosheets in this embodiment is as follows: Figure 1 As shown. By Figure 1 It can be seen that for the DN and F-DN curves at 3423cm -1 Stretch vibrations of the -OH group were observed at 1210 and 1149 cm⁻¹ for F-DN and PFDTES. -1 The presence of antisymmetric and symmetric stretching vibration peaks of CF2 at all locations indicates that the DN modification was successful.

[0060] Depend on Figure 2 It can be seen that the DN curve is at 1327cm. -1 There is a characteristic peak at 1324 cm⁻¹, while the F-DN curve has a peak at 1324 cm⁻¹. -1 There is a characteristic peak at this point, which is similar to the standard diamond peak (1332 cm). -1 Compared to the previous value, the value is slightly lower. This is because there is tensile stress in the diamond nanosheets, but their properties have not changed.

[0061] Depend on Figure 3 It can be seen that both DN and F-DN have two characteristic peaks corresponding to the {111} and {220} crystal planes of diamond, indicating that the crystallinity of diamond did not change much before and after modification.

[0062] Depend on Figure 4 It can be seen that F-DN showed almost no weight loss before 300℃, and after 300℃, the organic matter began to decompose, eventually decomposing completely at around 500℃, with a residual amount of 14.16%. In contrast, DN showed a smaller loss at the same temperature, only 7.2%, which further confirms the successful modification of F-DN.

[0063] Depend on Figure 5 As can be seen, the diamond nanosheets are completely encapsulated by the self-polymerized fluoride, which proves both the self-polymerization of the fluoride and the successful grafting of the diamond nanosheets with the fluorinated polymer. The structure of the diamond nanosheets can also be clearly seen from the figure.

[0064] Depend on Figure 6 It is known that F-DN has a melting point of 27.4℃ and a freezing point of 15.5℃, which gives it the characteristic of temperature response.

[0065] Example 2

[0066] This embodiment is a test of the self-healing ability of the fluorinated nanodiamond sheet anti-corrosion coating provided in Example 1 above.

[0067] An artificial notch (approximately 2 mm wide and 200 μm deep) was created in the anti-corrosion coating of a fluorinated nanodiamond sheet. The sheet was then placed in an environment of 120°C to allow for self-healing. Optical images and 3D contour images of the surface morphology changes over time were recorded using a laser confocal microscope.

[0068] Figure 7 The images shown in A and B are, in order, optical images of the initial coating state and optical images and 3D contour images after a repair time of 60 minutes (repair temperature was 120℃, with each repair interval being 10 minutes). Figure 7 'a' represents the initial state of the coating. Figure 7 b. Damaged coating condition Figure 7 c represents the coating repair state after 10 minutes, and so on. From Figure 7 According to AH, when the healing time of the coating wound is 0-40 minutes, the area of ​​the damaged site mainly shrinks, while the wound depth heals relatively slowly. After 50 minutes, the wound gradually flattens out, and... Figure 7 In g, the base is no longer visible at the damaged location, and Figure 7 The damage to the intermediate coating has basically disappeared.

[0069] Figure 8 The cross-sectional profile curve in Figure a also shows that the profile curve after 60 minutes of healing almost coincides with the initial curve of the coating, which can be basically considered as the coating completing the repair of a 2mm wide wound in 60 minutes. Figure 8 Figure b shows the curves of the maximum volume and depth of the coating scratch as a function of healing time. The figure indicates that the depth of the coating wound changes relatively slowly in the first 40 minutes, but decreases sharply during the self-healing period from 40 to 50 minutes, dropping from 138 μm to 15 μm, and finally decreasing to 4 μm after 60 minutes. Meanwhile, the maximum volume of the coating wound gradually decreases with healing time, from an initial 2.126 mm. 3 Reduced to 0.023mm 3 The repair rate is approximately 98.92%. Therefore, it can be concluded that wounds treated with fluorinated nanodiamond sheets with anti-corrosion coating can be essentially completely healed after 60 minutes of self-healing time at 120°C.

[0070] Example 3

[0071] This embodiment illustrates the corrosion resistance test of the fluorinated nanodiamond sheet anti-corrosion coating provided in Embodiment 1 above before and after two self-healing cycles, as well as the test of the control sample.

[0072] The electrodynamic polarization curves and electrochemical impedance spectroscopy (EIS) of the samples were measured using an electrochemical workstation. The electrolyte was a 3.5 wt% NaCl solution, with a calomel electrode as the reference electrode, a platinum electrode as the counter electrode, and a working electrode with an exposure area of ​​1 cm². 2 The sample. The EIS test frequency range is 10. 5 Hz to 10 -2The Hz, the scan rate of the potentiodynamic polarization test was 0.5 mVs⁻¹. Two damage-self-healing cycles were performed on the coating sample, corresponding to the coating damage repair in Example 2.

[0073] Figure 9 a1 shows Nyquist plots of a pure Q235 steel plate and a steel plate coated with a fluorinated diamond nanosheet anti-corrosion coating before and after two self-healing cycles. Figure 9 a2 shows Bode plots of a pure Q235 steel plate and a steel plate coated with a fluorinated diamond nanosheet anti-corrosion coating before and after two self-healing cycles. Figure 9 a3 shows the Tafel curves of pure Q235 steel plate and steel plate coated with fluorinated diamond nanosheet anti-corrosion coating before and after two self-healing cycles. The graphs show that the fluorinated diamond nanosheet anti-corrosion coating has better corrosion resistance than the pure Q235 steel plate. Although the anti-corrosion performance is slightly reduced after two cycles of damage and self-healing, it does not affect its overall anti-corrosion performance and still provides good protection for the metal substrate.

[0074] Example 4

[0075] This embodiment illustrates the corrosion resistance test of the fluorinated nanodiamond sheet anti-corrosion coating provided in Embodiment 1 above before and after low-temperature impact.

[0076] The electrodynamic polarization curves and electrochemical impedance spectroscopy (EIS) of the samples were measured using an electrochemical workstation. The electrolyte was a 3.5 wt% NaCl solution, with a calomel electrode as the reference electrode, a platinum electrode as the counter electrode, and a working electrode with an exposure area of ​​1 cm². 2 The sample. The EIS test frequency range is 10. 5 Hz to 10 -2 The Hz readings were obtained, and the scan rate for the potentiodynamic polarization test was 0.5 mV s⁻¹. The sample was placed at -65°C for 15 hours before electrochemical testing.

[0077] Figure 10 a1 shows the Nyquist plots of the steel plate coated with fluorinated diamond nanosheet anti-corrosion coating after being placed at room temperature and -64℃ for 15 hours. Figure 10 a2 shows the Bode plots of a steel plate coated with fluorinated diamond nanosheets for corrosion protection after being placed at room temperature and -64℃ for 15 hours. Figure 10 a3 shows Tafel graphs of steel plates coated with fluorinated diamond nanosheets after being placed at room temperature and -64℃ for 15 hours. The graphs show that after 15 hours of low-temperature impact, the anti-corrosion performance of the coating did not decrease significantly compared to its initial state. This indicates that even in the extremely cold environment of -64℃, the fluorinated diamond nanosheet coating can still provide good protection for the metal substrate.

[0078] Example 5

[0079] This embodiment demonstrates the long-term corrosion resistance test of the fluorinated nanodiamond sheet anti-corrosion coating provided in Embodiment 1 above.

[0080] Pure Q235 steel plate and steel plate coated with fluorinated diamond nanosheet anti-corrosion coating were respectively immersed in 100ml of 3.5wt% NaCl solution for 35 days. Both were then encapsulated with epoxy resin to ensure that only an area of ​​1cm² was exposed. 2 The surfaces of the two steel plates were characterized using scanning electron microscopy, atomic force microscopy, and ultraviolet spectroscopy after 35 days.

[0081] Figure 11 Images a1-a3 are, respectively, SEM, selected area elemental analysis, and atomic force microscopy images of the surface roughness of pure Q235 steel plates after immersion for 35 days. Figure 12 Images b1-b3 show, respectively, SEM, selected area elemental analysis, and atomic force microscopy images of the surface roughness of steel plates coated with fluorinated diamond nanosheets after immersion for 35 days. The images reveal a significant change in the surface morphology of the pure Q235 steel plate, with a marked increase in roughness and surface oxygen content. In contrast, the steel plate coated with fluorinated diamond nanosheets exhibits a smooth surface with lower roughness and a lower surface oxygen content. Figure 13 The images show the UV spectra of the immersion solutions collected after immersing pure Q235 steel plates and steel plates coated with fluorinated diamond nanosheets in a 3.5 wt% NaCl solution for 35 days. The spectra reveal the presence of iron ions in the immersion solution of the pure Q235 steel plate, while no iron ions were detected in the immersion solution of the steel plate coated with fluorinated diamond nanosheets. This indicates that the fluorinated diamond nanosheet anti-corrosion coating provides good protection even under long-term exposure to corrosive environments.

[0082] Based on the above embodiments, it is clear that the fluorinated diamond nanosheet anti-corrosion coating provided by the embodiments of the present invention has self-healing properties for repairing large-area damage, good anti-corrosion performance, and the ability to resist low-temperature impact and long-term corrosion protection.

[0083] It should be understood that the above embodiments are merely illustrative of the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A method for preparing a fluorinated diamond nanosheet anti-corrosion coating, characterized in that, Includes the following steps: (1) Disperse diamond nanosheets in deionized water to obtain a diamond nanosheet dispersion; dissolve a perfluorosilane coupling agent in an organic solvent to obtain a perfluorosilane coupling agent solution; mix the diamond nanosheet dispersion with the perfluorosilane coupling agent solution to obtain a mixed solution; (2) Add an alkaline catalyst to the mixed solution obtained in step (1) and react to obtain fluorinated diamond nanosheet polymer; (3) The fluorinated diamond nanosheet polymer obtained in step (2) is melted and coated onto the substrate, and then cooled and cured to obtain the fluorinated diamond nanosheet anti-corrosion coating. The concentration of the diamond nanosheet dispersion is 30-80 mg / mL, the concentration of the perfluorosilane coupling agent solution is 3-15 mg / mL, and the volume ratio of the diamond nanosheet dispersion to the perfluorosilane coupling agent solution is 1:10-15.

2. The preparation method according to claim 1, characterized in that, The diamond nanosheets have a diameter of 60-300 nm and a thickness of 10-30 nm.

3. The preparation method according to claim 1, characterized in that, The perfluorosilane coupling agent includes at least one of the following: triethoxy-1H,1H,2H,2H-nonafluorohexylsilane, triethoxy-1H,1H,2H,2H-tetrafluoro-N-octylsilane, 1H,1H,2H,2H-perfluorodecyltriethoxysilane, 1H,1H,2H,2H-perfluorooctyltrichlorosilane, or 1H,1H,2H,2H-perfluorodecyltrichlorosilane.

4. The preparation method according to claim 1 or 2, characterized in that, The alkaline catalyst includes at least one of sodium hydroxide, ammonia, trimethylamine, or tetrahydropyrimidine; the alkaline catalyst adjusts the pH of the mixed solution to 9-12.

5. The preparation method according to claim 1 or 2, characterized in that, In step (2), the reaction temperature is 25-60℃ and the time is 12-48h.

6. The preparation method according to claim 1 or 2, characterized in that, In step (3), the melting temperature of the fluorinated diamond nanosheet polymer is 50-120℃; the curing temperature of the fluorinated diamond nanosheet polymer is -10-20℃, and the curing time is 24-48h.

7. The anti-corrosion coating of fluorinated diamond nanosheets prepared by the preparation method according to any one of claims 1-6.

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