Preparation method of copper-anchored silicon defect montmorillonite-based anticorrosive material

Abstract

The present application relates to a kind of copper anchoring silicon defect montmorillonite-based anticorrosive material preparation method, by trace hydrofluoric acid etching montmorillonite, peeling off interlayer silicon atom to manufacture surface vacancy, with inorganic montmorillonite as carrier, interlayer silicon vacancy anchors copper ion to capture conductive polymer, realize in montmorillonite interlayer stable in situ polymerization.Polymer-montmorillonite is used as filler, and montmorillonite-based composite anticorrosive coating is prepared by coating method.Adding layered montmorillonite in coating matrix not only can provide physical barrier, prevent water, corrosive ion in environment from diffusing into substrate, but also can make conductive polymer maintain good dispersibility and long-term service stability in coating matrix, play the role of electrochemical shielding, thereby avoid the possibility of electrochemical reaction between corrosive substance and substrate, increase the corrosion resistance of coating.Preparation method, process is simple, reaction condition is mild;Raw material and equipment are cheap and easy to obtain, low cost;Synthesis efficiency is high, suitable for large-scale production.

Description

Technical Field

[0001] This invention relates to montmorillonite-based anti-corrosion coatings, specifically to a method for preparing a copper-anchored silicon-defect montmorillonite-based anti-corrosion material. Background Technology

[0002] In certain environments, such as soil, seawater, and exploration boreholes, coatings are needed to provide better protection against certain corrosive substances. Adding functional fillers to coatings is crucial for adjusting coating performance or developing new functions. Montmorillonite can be functionalized through ion exchange, intercalation, and exfoliation. Rigid montmorillonite fillers incorporated into the matrix coating can effectively inhibit the penetration of corrosive substances, thus giving the coating strong corrosion resistance. Simultaneously, conductive polymers can act as corrosion inhibitors, effectively reducing the corrosion rate of the coating. Composite materials combining conductive polymers and montmorillonite are a promising filler. However, the presence of numerous impurity ions between montmorillonite layers and the poor competitiveness of polymer monomers for montmorillonite intercalation make it difficult to achieve stable loading of conductive polymers. Furthermore, polymer segments are easily lost after ordinary intercalation, leading to a decline in the long-term service life of the anti-corrosion coating. Therefore, improving the compatibility of these two materials to enable their synergistic effect and enhance the anti-corrosion durability of the coating remains a pressing issue. Summary of the Invention

[0003] The purpose of this invention is to address the shortcomings of existing technologies by providing a method for preparing a copper-anchored silicon-defect-based montmorillonite-based anti-corrosion material. By reacting a trace amount of hydrofluoric acid (HF) with the O-Si on the surface of montmorillonite layers, some Si is etched into vacancies, giving these vacancies a certain degree of negative charge. Subsequently, copper active sites capable of capturing and anchoring conductive monomers are introduced. Long-chain conductive polymers are then firmly anchored to these copper sites between the montmorillonite layers using in-situ polymerization. The hydrophobic and anti-corrosion properties of the montmorillonite-based composite anti-corrosion material as a filler in the coating are investigated. Montmorillonite is dispersed in the polymer coating, and the conductive polymer acts as a corrosion inhibitor, inserted into and anchored within the montmorillonite layers, significantly improving the corrosion resistance of the composite anti-corrosion coating. The combination of the conductive polymer and the dispersed montmorillonite nanolayers results in a coating with low surface free energy, and the two exhibit strong compatibility. Through synergistic effects, the composite anti-corrosion coating achieves long-term corrosion resistance.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A method for preparing a copper-anchored silicon defect montmorillonite-based anti-corrosion material includes the following steps:

[0006] (1) Preparation of montmorillonite powder with copper anchoring defects: First, the surface of montmorillonite is etched: 65-80g of montmorillonite is added to 800-1000mL of deionized water and stirred at 80℃ until uniformly mixed. An acidic regulator is added and stirred evenly to adjust the pH to 2-6. Then, HF aqueous solution is added at a rate of 0.1mL / s and stirred for 2-4h to obtain a yellow precipitate. The yellow precipitate is washed by centrifugation, dried and ground to obtain montmorillonite powder with silicon vacancies. Finally, the obtained montmorillonite powder with defects is added to 80-100mL of 5-10mol / L copper sulfate solution and stirred for half an hour to fully impregnate for 10-12h. The powder is filtered, dried and ground to obtain montmorillonite powder with copper anchoring defects.

[0007] (2) Intercalation of conductive polymer: Copper-anchored montmorillonite-loaded conductive polymer composite powder was prepared by in-situ intercalation polymerization: 10-40g of copper-anchored montmorillonite powder and 0.8-1.5mol of conductive polymer monomer prepared in step (1) were added to 400-800mL of deionized water and stirred evenly. Then, an initiator aqueous solution was added dropwise at a rate of 0.05mL / s while stirring evenly at room temperature to make the conductive polymer monomer and copper ions firmly polymerize and obtain a precipitate. The precipitate was centrifuged, washed, dried and ground, and passed through a 200-mesh sieve to obtain copper-anchored montmorillonite-loaded conductive polymer composite powder.

[0008] (3) Preparation of anti-corrosion material: 3-8g of copper-anchored montmorillonite-loaded conductive polymer composite powder prepared in step (2) is added to 80-100g of epoxy resin and dissolved evenly. After stirring at room temperature, epoxy resin curing agent is added and stirred. The mixture is then ultrasonicated to eliminate air bubbles, thus obtaining copper-anchored silicon-defect montmorillonite-based anti-corrosion material. In this application, epoxy resin model E51 purchased from Langfang Rongwei Anti-corrosion Materials Co., Ltd. is used, and the epoxy resin curing agent is polyamide curing agent 650.

[0009] Further, the acid regulator in step (1) is selected from dilute hydrochloric acid, dilute sulfuric acid, and dilute nitric acid, with a concentration of 0.5-1 mol / L and a stirring speed of 100-400 rpm.

[0010] Further, the conductive polymer monomer in step (2) is selected from one of 2-mercaptoaniline, 2-mercaptopyridine, and 3-mercaptothiophene.

[0011] Further, the initiator in step (2) is selected from one of ammonium persulfate, hydrogen peroxide, potassium dichromate, and ferric chloride.

[0012] Further, the concentration of the HF aqueous solution in step (1) is 40wt%, the amount is 3-8mL, the stirring speed is 200rpm, and the stirring temperature is 40℃.

[0013] Further, the centrifugal washing in step (1) involves alternating washing with anhydrous ethanol and deionized water 2-4 times, and the drying involves drying in a vacuum environment at 60-80℃ for 6-8 hours.

[0014] Further, the initiator aqueous solution in step (2) is a 0.1 mol / L initiator aqueous solution prepared with 1-4 g of initiator, and the stirring time at room temperature is 12 h.

[0015] Further, the centrifugal washing in step (2) involves washing with deionized water 2-4 times, and the drying involves drying in a vacuum environment at 60-80℃ for 6-8 hours.

[0016] Further, in step (3), the amount of epoxy resin curing agent is 20-50 wt% of the epoxy resin mass, and the mixture is stirred for 10 min and sonicated for 5 min.

[0017] The beneficial effects of this invention are as follows:

[0018] (1) The present invention prepares surface-defect montmorillonite, obtains charged silicon vacancies, and then adsorbs copper ions as trapping sites for polymer monomers. The copper ions have strong inter-bonding with the mercapto-conductive polymer, thereby achieving stable loading of conductive polymers on montmorillonite through in-situ polymerization. This improves the compatibility between the montmorillonite matrix and the functional conductive polymers, solves the problem of easy loss of polymer chain segments during ordinary intercalation, and synergistically reduces the corrosion rate of the material. Furthermore, using this composite powder as a filler, a novel epoxy resin-based composite anti-corrosion coating is prepared by coating method, improving the long-term service performance of the coating.

[0019] (2) The present invention adds layered montmorillonite to the epoxy resin coating, which can not only provide a physical barrier to prevent water and corrosive ions in the environment from diffusing into the substrate, but also improve the dispersion and long-term service stability of conductive polymers in epoxy resin, and play an electrochemical shielding role, thereby avoiding the possibility of electrochemical reaction with the substrate and increasing the corrosion resistance of the coating.

[0020] (3) The method provided by the present invention has mild reaction conditions, simple operation process, short reaction cycle and high repeatability. Attached Figure Description

[0021] Figure 1 This is a process flow diagram of the present invention;

[0022] Figure 2 The image shown is a transmission electron microscope (TEM) image of the silicon-defect montmorillonite-based anti-corrosion material obtained in Example 1 of this invention.

[0023] Figure 3 The dynamic polarization curves of the anti-corrosion coatings obtained in Example 1 and Comparative Example 1 are shown.

[0024] Figure 4 These are photographs of the salt spray test obtained in Example 1 of the present invention;

[0025] Figure 5 These are photographs of the salt spray test obtained in Example 2 of the present invention;

[0026] Figure 6 This is a photograph of the salt spray test obtained in Comparative Example 2 of the present invention. Detailed Implementation

[0027] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided below.

[0028] This invention introduces long-chain conductive polymers into copper ions between montmorillonite layers through in-situ polymerization, thereby improving the compatibility between the montmorillonite matrix and the functional conductive polymer, and the prepared anti-corrosion material has strong corrosion resistance.

[0029] Example 1

[0030] This embodiment uses, as follows: Figure 1 The process flow and specific steps are as follows:

[0031] (1) First, the surface of montmorillonite was etched. 72g of montmorillonite was added to 900mL of deionized water and stirred at 80℃ until uniformly mixed. 0.6mol / L dilute hydrochloric acid was added and stirred at 200rpm to adjust the pH to 4. Then, 5mL of 40% HF was added at a rate of 0.1mL / s and stirred at 200rpm and 40℃. After stirring for 2h, a yellow precipitate was obtained. The precipitate was washed three times with anhydrous ethanol and deionized water and dried at 70℃ for 7h. The precipitate was then ground to obtain defective montmorillonite powder with silicon vacancies. Finally, the defective montmorillonite powder was added to 100mL of 10mol / L copper sulfate solution and stirred for half an hour to fully impregnate for 12h. The powder was then filtered, dried and ground to obtain copper-anchored defective montmorillonite powder.

[0032] (2) Add 20g of copper-anchored montmorillonite powder and 1.0mol of 2-mercaptoaniline prepared in step (1) to 600mL of deionized water and stir evenly to obtain solution A. Prepare 0.1mol / L ammonium persulfate solution with 2g of ammonium persulfate and then add it dropwise to solution A at a rate of 0.05mL / s. Stir at room temperature for 12h to allow 2-mercaptoaniline to polymerize firmly with copper ions and obtain a precipitate. Wash the precipitate three times with deionized water by centrifugation and dry it under vacuum at 70℃. Grind the dried sample and pass it through a 200-mesh sieve to obtain copper-anchored montmorillonite-supported conductive polymer composite powder.

[0033] (3) Add 4g of copper-anchored montmorillonite-loaded conductive polymer composite powder prepared in step (2) to 96g of epoxy resin and dissolve evenly. After stirring at room temperature, add 40g of epoxy resin curing agent and stir. Ultrasonicate to eliminate bubbles to obtain copper-anchored silicon defect montmorillonite-based anti-corrosion material.

[0034] The coating was applied to a stainless steel substrate, and the coated sample was placed in a vacuum drying oven at 60°C for 12 hours before testing.

[0035] Transmission electron microscopy images of the obtained silicon-defect montmorillonite-based anticorrosive material are as follows: Figure 2 As shown, this indicates that the material has a uniform lamellar structure.

[0036] Electrochemical testing of the obtained anti-corrosion coating samples in 3.5 wt% NaCl solution: Dynamic polarization curves of the stainless steel substrate and coating were tested using a Shanghai Chenhua electrochemical workstation (CH1660D). The Tafel curve test potential range was -1.3 to -0.6 V, and the scan rate was 0.005 V / s. Figure 3 The dynamic polarization curves of the anti-corrosion coating sample, epoxy resin sample, and stainless steel sample show a positive shift in corrosion potential. The decrease in corrosion current indicates the high efficiency of the composite anti-corrosion coating in protecting the stainless steel substrate.

[0037] The obtained anti-corrosion coating samples were subjected to salt spray testing in a 5wt% NaCl solution: After the surface of the composite anti-corrosion coating was scratched, it was placed in a salt spray chamber for 200 hours of high-concentration salt spraying. Figure 4 The results of the salt spray test on the anti-corrosion coating showed no defects such as blistering or cracking, indicating that the coating has not failed and maintains good long-term corrosion resistance.

[0038] Example 2

[0039] This embodiment uses, as follows: Figure 1 The process flow and specific steps are as follows:

[0040] (1) First, the surface of montmorillonite was etched. 65g of montmorillonite was added to 800mL of deionized water and stirred at 80℃ until uniformly mixed. 0.5mol / L dilute sulfuric acid was added and stirred at 100rpm to adjust the pH to 6. Then, 3mL of 40% HF was added at a rate of 0.1mL / s and stirred at 200rpm and 40℃. After stirring for 2h, a yellow precipitate was obtained. The precipitate was washed twice with anhydrous ethanol and deionized water and dried at 60℃ for 8h. The precipitate was then ground to obtain defective montmorillonite powder with silicon vacancies. Finally, the defective montmorillonite powder was added to 80mL of 5mol / L copper sulfate solution and stirred for half an hour to fully impregnate for 11h. The powder was then filtered, dried and ground to obtain copper-anchored defective montmorillonite powder.

[0041] (2) Add 10g of copper-anchored montmorillonite powder and 0.8mol of 2-mercaptopyridine prepared in step (1) to 400mL of deionized water and stir evenly to obtain solution A. Prepare 1g of ferric chloride into a 0.1mol / L ferric chloride solution and then add it dropwise to solution A at a rate of 0.05mL / s. Stir at room temperature for 12h to allow 2-mercaptopyridine to firmly polymerize with copper ions and obtain a precipitate. Wash the precipitate twice with deionized water by centrifugation and dry it under vacuum at 60℃ for 8h. Grind the dried sample and pass it through a 200-mesh sieve to obtain copper-anchored montmorillonite-supported conductive polymer composite powder.

[0042] (3) Add 3g of copper-anchored montmorillonite-loaded conductive polymer composite powder prepared in step (2) to 80g of epoxy resin and dissolve it evenly. After stirring at room temperature, add 16g of epoxy resin curing agent and stir for 10min. Ultrasound to eliminate bubbles to obtain copper-anchored silicon defect montmorillonite-based anti-corrosion material.

[0043] The coating was applied to a stainless steel substrate, and the coated sample was placed in a vacuum drying oven at 60°C for 12 hours before testing.

[0044] The obtained anti-corrosion coating samples were subjected to salt spray testing in a 5wt% NaCl solution: After the surface of the composite anti-corrosion coating was scratched, it was placed in a salt spray chamber for 200 hours of high-concentration salt spraying. Figure 5 The results of the salt spray test on the anti-corrosion coating showed no defects such as blistering or cracking, indicating that the coating has not failed and maintains good long-term corrosion resistance.

[0045] Example 3

[0046] This embodiment uses, as follows: Figure 1 The process flow and specific steps are as follows:

[0047] (1) First, the surface of montmorillonite was etched. 80g of montmorillonite was added to 1000mL of deionized water and stirred at 80℃ until uniformly mixed. 1mol / L dilute nitric acid was added and stirred at 400rpm to adjust the pH to 2. Then, 8mL of 40% montmorillonite was added at a rate of 0.1mL / s and stirred at 200rpm and 40℃. After stirring for 2h, a yellow precipitate was obtained. The precipitate was washed 4 times with anhydrous ethanol and deionized water alternately and dried at 80℃ for 6h. The precipitate was then ground to obtain defective montmorillonite powder with silicon vacancies. Finally, the defective montmorillonite powder was added to 90mL of 8mol / L copper sulfate solution and stirred for half an hour to fully impregnate for 10h. The powder was then filtered, dried and ground to obtain copper-anchored defective montmorillonite powder.

[0048] (2) Add 40g of copper-anchored montmorillonite powder and 1.5mol of 3-mercaptothiophene prepared in step (1) to 800mL of deionized water and stir evenly to obtain solution A. Prepare 0.1mol / L potassium dichromate solution with 4g of potassium dichromate and then add it dropwise to solution A at a rate of 0.05mL / s. Stir at room temperature for 12h to allow 3-mercaptothiophene to polymerize firmly with copper ions and obtain a precipitate. Wash the precipitate with deionized water by centrifugation 4 times and vacuum dry at 80℃ for 6h. Grind the dried sample and pass it through a 200-mesh sieve to obtain copper-anchored montmorillonite-supported conductive polymer composite powder.

[0049] (3) Add 100g of epoxy resin to the 8g of montmorillonite-loaded conductive polymer composite powder prepared in step (2) and dissolve it evenly. After stirring at room temperature, add 50g of epoxy resin curing agent and stir for 10min. Ultrasound to eliminate bubbles to obtain copper-anchored silicon defect montmorillonite-based anti-corrosion material.

[0050] Comparative Example 1

[0051] (1) First, the surface of montmorillonite was etched. 72g of montmorillonite was added to 900mL of deionized water and stirred at 80℃ until uniformly mixed. 0.6mol / L dilute hydrochloric acid was added and stirred at 200rpm to adjust the pH to 4. Then, 5mL of 40% HF was added at a rate of 0.1mL / s and stirred at 200rpm and 40℃. After stirring for 2h, a yellow precipitate was obtained. The precipitate was washed three times alternately with anhydrous ethanol and deionized water and dried at 70℃ for 7h. The precipitate was then ground to obtain montmorillonite powder with silicon vacancies.

[0052] (2) Add 20g of defective montmorillonite powder and 1.0mol of 2-mercaptoaniline prepared in step (1) to 600mL of deionized water and stir evenly to obtain solution A. Prepare 2g of ammonium persulfate into a 0.1mol / L ammonium persulfate solution, and then add it dropwise to solution A at a rate of 0.05mL / s. Stir at room temperature for 12h to allow 2-mercaptoaniline to polymerize in situ at silicon vacancies to obtain a precipitate. Wash the precipitate three times with deionized water by centrifugation, and dry it under vacuum at 70℃. Grind the dried sample and pass it through a 200-mesh sieve to obtain montmorillonite-supported conductive polymer composite powder.

[0053] (3) Add 4g of montmorillonite-loaded conductive polymer composite powder prepared in step (2) to 96g of epoxy resin and dissolve it evenly. After stirring at room temperature, add 40g of epoxy resin curing agent and stir. Ultrasound to eliminate bubbles to obtain silicon defect montmorillonite-based anti-corrosion material.

[0054] The coating was applied to a stainless steel substrate, and the coated sample was placed in a vacuum drying oven at 60°C for 12 hours before testing.

[0055] Electrochemical testing of the obtained anti-corrosion coating sample in 3.5wt% NaCl solution: First, dynamic polarization curve testing was carried out on the stainless steel substrate and coating using a Shanghai Chenhua electrochemical workstation (CH1660D). The Tafel curve test potential range was -1.3 to -0.6 V, and the scan rate was 0.005 V / s. Figure 3 The dynamic polarization curves of the anti-corrosion coating sample, epoxy resin sample, and stainless steel sample prepared by the comparative sample were compared with those of Example 1, demonstrating that the anchoring of copper ions effectively improves the anti-corrosion performance of the material, indicating that the composite anti-corrosion coating prepared by the method of the present invention provides efficient protection for stainless steel substrates.

[0056] Comparative Example 2

[0057] (1) First, the surface of montmorillonite was etched. 72g of montmorillonite was added to 900mL of deionized water and stirred at 80℃ until uniformly mixed. 0.6mol / L dilute hydrochloric acid was added and stirred at 200rpm to adjust the pH to 4. After stirring for 2h, it was washed three times alternately with anhydrous ethanol and deionized water and dried at 70℃ for 7h. The powder was then ground to obtain montmorillonite powder with no silicon defects. Finally, the obtained defective montmorillonite powder was added to 90mL of 8mol / L copper sulfate solution and stirred for half an hour to fully impregnate for 10h. The powder was then filtered, dried and ground to obtain copper-adsorbed montmorillonite powder.

[0058] (2) Add 20g of copper-adsorbed montmorillonite powder and 1.0mol of 2-mercaptoaniline prepared in step (1) to 600mL of deionized water and stir evenly to obtain solution A. Prepare 2g of ammonium persulfate into a 0.1mol / L ammonium persulfate solution and then add it dropwise to solution A at a rate of 0.05mL / s. Stir at room temperature for 12h to allow 2-mercaptoaniline to polymerize with copper sites and obtain a precipitate. Wash the precipitate three times with deionized water by centrifugation and dry it under vacuum at 70℃. Grind the dried sample and pass it through a 200-mesh sieve to obtain montmorillonite-loaded conductive polymer composite powder.

[0059] (3) Add 4g of montmorillonite-loaded conductive polymer composite powder prepared in step (2) to 96g of epoxy resin and dissolve it evenly. After stirring at room temperature, add 40g of epoxy resin curing agent and stir. Ultrasound to eliminate bubbles to obtain silicon defect montmorillonite-based anti-corrosion material.

[0060] The coating was applied to a stainless steel substrate, and the coated sample was placed in a vacuum drying oven at 60°C for 12 hours before testing.

[0061] The obtained anti-corrosion coating samples were subjected to salt spray testing in a 5wt% NaCl solution: After the surface of the composite anti-corrosion coating was scratched, it was placed in a salt spray chamber for 200 hours of high-concentration salt spraying. Figure 6 The salt spray test results of the anti-corrosion coating in Comparative Example 2 showed blistering and pitting, indicating coating failure. This demonstrated the strong interaction between silicon defects and copper ion anchoring, thus effectively improving the long-term anti-corrosion stability of the coating.

[0062] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A method for preparing a copper-anchored silicon defect montmorillonite-based anti-corrosion material, characterized in that, Includes the following steps: (1) Preparation of montmorillonite powder with copper anchoring defects: First, the surface of montmorillonite is etched: 65-80 g of montmorillonite is added to 800-1000 mL of deionized water and stirred at 80 °C until uniformly mixed. An acidic regulator is added and stirred evenly to adjust the pH to 2-6. Then, HF aqueous solution is added at a rate of 0.1 mL / s and stirred for 2-4 h to obtain a yellow precipitate. The yellow precipitate is washed by centrifugation, dried and ground to obtain montmorillonite powder with silicon vacancies. Finally, the obtained montmorillonite powder with defects is added to 80-100 mL of 5-10 mol / L copper sulfate solution and stirred for half an hour to fully impregnate for 10-12 h. The powder is filtered, dried and ground to obtain montmorillonite powder with copper anchoring defects. (2) Intercalation of conductive polymer: Copper-anchored montmorillonite-loaded conductive polymer composite powder was prepared by in-situ intercalation polymerization: 10-40 g of copper-anchored defect montmorillonite powder prepared in step (1) and 0.8-1.5 mol of conductive polymer monomer were added to 400-800 mL of deionized water and stirred evenly. Then, an initiator aqueous solution was added dropwise at a rate of 0.05 mL / s while stirring evenly at room temperature to make the conductive polymer monomer and copper ions firmly polymerize and obtain a precipitate. The precipitate was centrifuged, washed, dried and ground, and passed through a 200-mesh sieve to obtain copper-anchored montmorillonite-loaded conductive polymer composite powder; the conductive polymer monomer was selected from one of 2-mercaptoaniline, 2-mercaptopyridine, and 3-mercaptothiophene. (3) Preparation of anti-corrosion material: 3-8 g of copper-anchored montmorillonite-loaded conductive polymer composite powder prepared in step (2) is added to 80-100 g of epoxy resin and dissolved evenly. After stirring at room temperature, epoxy resin curing agent is added and stirred. Ultrasonication is used to eliminate bubbles to obtain copper-anchored silicon defect montmorillonite-based anti-corrosion material.

2. The method according to claim 1, characterized in that, The acid regulator in step (1) is selected from dilute hydrochloric acid, dilute sulfuric acid, and dilute nitric acid, with a concentration of 0.5-1 mol / L and a stirring speed of 100-400 rpm.

3. The method according to claim 1, characterized in that, The initiator in step (2) is selected from one of ammonium persulfate, hydrogen peroxide, potassium dichromate, and ferric chloride.

4. The method according to claim 1, characterized in that, The concentration of the HF aqueous solution in step (1) is 40 wt%, the amount used is 3-8 mL, the stirring speed is 200 rpm, and the stirring temperature is 40 ℃.

5. The preparation method according to claim 1, characterized in that, The centrifugal washing in step (1) involves washing with anhydrous ethanol and deionized water alternately 2-4 times, and the drying involves drying in a vacuum environment at 60-80 ℃ for 6-8 h.

6. The method according to claim 1, characterized in that, The initiator aqueous solution in step (2) is a 0.1 mol / L initiator aqueous solution prepared by 1-4 g of initiator, and the stirring time at room temperature is 12 h.

7. The preparation method according to claim 1, characterized in that, The centrifugal washing in step (2) involves washing with deionized water 2-4 times, and the drying involves drying in a vacuum environment at 60-80 ℃ for 6-8 hours.

8. The method according to claim 1, characterized in that, In step (3), the amount of epoxy resin curing agent used is 20-50 wt% of the epoxy resin mass, and the mixture is stirred for 10 min and ultrasonically sonicated for 5 min.

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