An anti-corrosion and anti-icing super-hydrophobic coating, and a preparation method and application thereof

Abstract

This invention relates to a superhydrophobic coating with anti-corrosion and anti-icing properties, its preparation method, and its application, belonging to the field of protective coating technology. The coating preparation method includes: dispersing metal oxide nanoparticle powder in a blend solution containing hydrochloric acid and o-methoxyaniline monomer, stirring and reacting in an ice-water bath, then slowly adding an ammonium persulfate aqueous solution, continuing the stirring reaction to obtain a hydrochloric acid-doped POA / NPs composite material; dispersing it in an ammonia aqueous solution, stirring and reacting at room temperature to obtain a dedoped powder; blending it with epoxy resin and polydimethylsiloxane in a blend solvent of anhydrous ethanol and N-methylpyrrolidone, adding fatty acids, heating and stirring in a water bath, and then uniformly spraying it onto a substrate to obtain the coating. The coating obtained by this invention is a superhydrophobic coating with excellent anti-corrosion and anti-icing properties, and can be used for comprehensive protection of marine engineering and wind power generation equipment.

Description

Technical Field

[0001] This invention relates to a superhydrophobic coating that is corrosion-resistant and anti-icing, its preparation method, and its application, belonging to the field of protective coating technology. Background Technology

[0002] With the rapid development of the steel industry, metal materials exposed to extreme environments such as humidity, high temperature, ultra-low temperature, ocean, and acid rain for extended periods suffer performance degradation. This not only causes severe economic losses but also generates a series of safety issues. Therefore, research on metal corrosion protection technology is of great significance for practical applications. Among numerous corrosion prevention methods, organic coatings have attracted widespread attention due to their excellent physical barrier properties, chemical stability, and cost-effectiveness. Organic coating precursors, such as organic paints, mainly consist of film-forming substances, solvents, and pigments and fillers. The pigments and fillers are primarily lead-based and chromate-based heavy metal rust-preventive pigments, which offer excellent performance and are relatively inexpensive. However, the preparation of these pigments and fillers can easily pollute the environment. The lead they contain can cause chronic lead poisoning through skin, digestion, and inhalation, and hexavalent chromium ions in chromates are carcinogenic. Therefore, developing economical, environmentally friendly, and intelligent new corrosion-resistant coatings has become an urgent goal.

[0003] In recent years, polyaniline (PANI) has been considered an environmentally friendly coating material that aligns with modern technological development due to its easy synthesis, non-toxicity, high conductivity, good chemical and environmental stability, and reversible redox properties. However, the difficulty in melting and processing of PANI leads to a non-dense coating structure, weak adhesion to metal substrates, and insufficient durability in corrosive environments, limiting its practical applications. Poly(o-methoxyaniline) (POA), a derivative of PANI, is considered the most promising material for practical applications due to its good solubility, electrical conductivity, and processability. Inspired by the "lotus effect" in nature, superhydrophobicity has attracted widespread attention from researchers. Generally, surfaces with a water contact angle greater than 150° and a roll-off angle less than 10° are called superhydrophobic surfaces. Superhydrophobic surfaces are used for metal protection because they can effectively prevent the diffusion of corrosive substances to metal surfaces. Combining the superhydrophobic properties of hydrophobic materials with the excellent properties of conductive polymers holds promise for developing higher-performance metal protective layers. CN105623497B discloses a polyaniline coating and its preparation method. This coating, through a carefully proportioned combination of raw materials, successfully produces a pollution-free and low-cost environmentally friendly anti-corrosion coating. This coating solves the environmental pollution problem caused by the large amounts of organic solvents and heavy metal zinc in traditional anti-corrosion coatings, while exhibiting excellent anti-corrosion performance at a relatively low thickness, effectively reducing material consumption and costs. However, problems such as complex operating procedures, coating uniformity, precise condition control, and long-term durability still exist. CN118165613A discloses a hydrophobic modified anti-corrosion coating and its preparation method. It uniformly disperses polyaniline composite nanomaterials in an aqueous epoxy resin and further cures them by immersion in a homogeneous PDMS solution to obtain a hydrophobic modified anti-corrosion coating. This successfully solves the problems of insufficient solubility, adhesion, and density of traditional polyaniline coatings, while endowing the coating with high hydrophobicity and excellent anti-corrosion performance. However, the etching and photopolymerization reaction conditions in the preparation process are relatively harsh, the raw material handling process is complex, and it produces acid and alkali waste that pollutes the environment. Meanwhile, a single protective mechanism cannot simultaneously achieve hydrophobicity, corrosion resistance, and anti-icing properties. Therefore, developing a superhydrophobic surface coating that is simple to process, environmentally friendly, efficient, and offers multiple protective functions is of great significance for improving the protective performance of materials. Summary of the Invention

[0004] To address the technical problems of complex preparation processes, harsh conditions, high costs, poor corrosion resistance, and low-temperature icing in existing protective coating technologies, this invention provides a corrosion-resistant and icing-resistant superhydrophobic coating, its preparation method, and its application.

[0005] A method for preparing a corrosion-resistant and anti-icing superhydrophobic coating includes the following steps:

[0006] (1) Disperse metal oxide nanoparticle powder in a mixed solution containing hydrochloric acid (HCl) and o-methoxyaniline monomer (OA) to obtain a suspension; place it in an ice-water bath and stir to react, then slowly add ammonium persulfate aqueous solution, and continue stirring to react in an ice-water bath to obtain a black-purple suspension; filter, wash, and dry to obtain hydrochloric acid doped POA / NPs composite material; (2) The hydrochloric acid-doped POA / NPs composite material obtained in step (1) is dispersed in ammonia water (NH3·H2O) solution, stirred at room temperature, filtered, washed, and dried to obtain dedoped POA / NPs composite powder; it is then mixed with epoxy resin (EP) and polydimethylsiloxane (PDMS) in a mixed solvent of anhydrous ethanol and N-methylpyrrolidone (NMP), followed by the addition of fatty acids, and the reaction is carried out by water bath heating and stirring to obtain a coating; finally, the coating is uniformly sprayed onto the substrate and dried to obtain a superhydrophobic coating that is corrosion-resistant and anti-icing.

[0007] Furthermore, the substrate is a pretreated substrate, the specific process of which is as follows: the surface of the substrate is polished with 400-5000 grit metallographic sandpaper until there are no obvious scratches on the surface, and then ultrasonically cleaned with anhydrous ethanol and deionized water at room temperature.

[0008] More preferably, the substrate is a carbon steel sheet.

[0009] In the above technical solution, in step (1), the metal oxide nanoparticles are either zirconium oxide (ZrO2) nanoparticles or titanium oxide (TiO2) nanoparticles.

[0010] Further, in step (1), the metal oxide nanoparticles are prepared by the following method: an aqueous dispersion of the metal oxide is placed in a water bath at 45-70°C and stirred in the water bath, and then an alcoholic solution of γ-aminopropyltriethoxysilane (KH-550) is slowly added dropwise over 5-20 min. After stirring continuously for 2-4 h, the nanoparticles are obtained by filtration, washing, and drying. The mass ratio of the metal oxide to γ-aminopropyltriethoxysilane is 5-10:1.

[0011] In the above technical solution, in step (2), the fatty acid is one or both of stearic acid and myristic acid.

[0012] In the above technical solution, in step (1), the solid-liquid ratio of the metal oxide nanoparticle powder to the blended solution is 1:5-20; the molar ratio of o-methoxyaniline to ammonium persulfate is 1:1-1.5; in the blended solution, the concentration of hydrochloric acid is 0.3-2 mol / L, and the concentration of o-methoxyaniline is 0.02-0.3 mol / L.

[0013] In the above technical solution, in step (1), the suspension is placed in an ice-water bath at 0-5℃ and stirred for 15-40 minutes. Then, ammonium persulfate aqueous solution is slowly added dropwise. The entire addition process is completed within 15-20 minutes. The suspension is stirred and reacted in the ice-water bath for 6-8 hours to obtain a blackish-purple suspension. The suspension is then filtered, washed, and dried at 60-80℃ for 24 hours to obtain hydrochloric acid-doped POA / NPs composite material.

[0014] In the above technical solution, in step (2), the solid-liquid ratio of the hydrochloric acid-doped POA / NPs composite material to the ammonia solution is 1:5-25, and the concentration of the ammonia solution is 0.8-3 mol / L; in the coating, the mass fraction of the dedoped POA / NPs composite powder is 1-35 wt%, the mass fraction of the epoxy resin is 1-25 wt%, the mass fraction of the polydimethylsiloxane is 1-6 wt%, and the mass fraction of the fatty acid is 1-15 wt%; in the blending solvent, the volume ratio of anhydrous ethanol to N-methylpyrrolidone is 20-40:1.

[0015] Preferably, in the coating, the mass ratio of the de-doped POA / NPs composite powder to the mixture of epoxy resin and polydimethylsiloxane is 4:1, 2:1, 1:1 or 1:2.

[0016] In the above technical solution, in step (2), the room temperature stirring reaction time is 6-8 h; the water bath stirring conditions are 4-6 h at 60-70℃; and the drying conditions are 6-10 h at 40-60℃.

[0017] Another object of the present invention is to provide a corrosion-resistant and anti-icing superhydrophobic coating obtained by the above method.

[0018] Furthermore, the water contact angle of the superhydrophobic coating is 152.4°~161.2°, and the roll-off angle is 4.3°~6.2°.

[0019] Another object of the present invention is to provide the application of the anti-corrosion and anti-icing superhydrophobic coating obtained by the above method, or the above-mentioned anti-corrosion and anti-icing superhydrophobic coating, in the preparation of integrated protective materials for marine engineering and / or wind power generation.

[0020] The beneficial effects of this invention are as follows: the reagents used in the preparation method provided by this invention are all safe and non-toxic, posing little harm to operators and the environment; the operation method is simple and the process is straightforward, making it suitable for large-scale production. The surface morphology of the prepared coating consists of micro-nano-scale particles and lamellar structures, with enhanced surface hydrophobicity, and it also possesses excellent anti-corrosion and anti-icing properties. Attached Figure Description

[0021] Figure 1 SEM images of the coating (a) obtained in Comparative Example 1 and the superhydrophobic coating (b) obtained in Example 2.

[0022] Figure 2 The image shows the EDS diagram of the superhydrophobic coating obtained in Example 2.

[0023] Figure 3 The icing time results for bare carbon steel sheet (a) and the superhydrophobic coating obtained in Example 2 (b) are shown in the figure when the temperature of the cooling station is set to -15°C.

[0024] Figure 4 Tafel curves of bare carbon steel sheet (CS) and superhydrophobic coating (SPZC) obtained in Example 2 in 3.5% NaCl solution. Detailed Implementation

[0025] The following non-limiting embodiments are intended to enable those skilled in the art to more fully understand the invention, but do not limit the invention in any way.

[0026] Unless otherwise specified, the experimental methods described in the following examples are conventional methods; the reagents and materials described are commercially available unless otherwise specified.

[0027] Example 1 A method for preparing a corrosion-resistant and anti-icing superhydrophobic coating includes the following steps: (1) Pretreatment of carbon steel sheets The surface of the carbon steel sheet was polished with 400-5000 grit metallographic sandpaper until there were no obvious scratches. After polishing, the carbon steel sheet was ultrasonically cleaned with anhydrous ethanol and deionized water at room temperature to obtain the treated carbon steel sheet for later use.

[0028] (2) Preparation of metal oxide nanoparticles A 4 wt% aqueous dispersion of ZrO2 was placed in a water bath at 70°C and stirred. Then, an alcoholic solution of 0.8 wt% KH-550 was slowly added dropwise. The mass ratio of ZrO2 to KH-550 was 5:1. The addition was completed within 10 minutes. After stirring for 2 hours, the solution was filtered, washed, and dried in an oven at 80°C to obtain ZrO2 nanoparticle powder for later use.

[0029] (2) Preparation of hydrochloric acid-doped poly(o-methoxyaniline) / nano (POA / NPs) composite material HCl-doped POA-ZrO2 composite material was prepared by in-situ polymerization. ZrO2 nanoparticles were dispersed in a mixed solution of HCl and o-methoxyaniline monomer to form a suspension, with concentrations of HCl and o-methoxyaniline of 0.3 mol / L and 0.02 mol / L, respectively. The suspension was stirred in an ice-water bath at 0–5 °C for 30 min. Then, a 0.02 mol / L aqueous solution of ammonium persulfate was gradually added to the suspension over 15 min, with a molar ratio of o-methoxyaniline to ammonium persulfate of 1:1. After addition, stirring was continued in the ice-water bath for 6 h to ensure complete polymerization, yielding a dark purple suspension. The obtained suspension was then filtered, washed, and dried at 60 °C for 24 h to obtain hydrochloric acid-doped POA / NPs composite material powder.

[0030] (3) Preparation of coating Dry hydrochloric acid-doped POA / NPs composite powder was dispersed in a 1 mol / L NH3·H2O solution, stirred at room temperature for 6 h, filtered, washed, and dried to obtain dedoped POA / NPs composite powder. First, epoxy resin (EP) and PDMS were mixed at a mass ratio of 4:1 to obtain a mixture. Then, the dedoped POA / NPs composite powder was blended with the mixture at a mass ratio of 1:2 in a co-solvent consisting of 20 ml anhydrous ethanol and 0.5 ml N-methylpyrrolidone (NMP) to obtain a suspension. Finally, myristic acid was added, and the mixture was stirred in a 70°C water bath for 5 h to obtain a coating. The coating contained 4.95 wt% dedoped composite powder, 7.42 wt% epoxy resin, 3.46 wt% PDMS, and 2.47 wt% myristic acid. The prepared coating was uniformly sprayed onto a treated carbon steel sheet using a spray gun and then dried at 45°C for 6 h to form a coating layer.

[0031] Example 2 A method for preparing a corrosion-resistant and anti-icing superhydrophobic coating includes the following steps: (1) Pretreatment of carbon steel sheets The surface of the carbon steel sheet was polished with 400-5000 grit metallographic sandpaper until there were no obvious scratches. After polishing, the carbon steel sheet was ultrasonically cleaned with anhydrous ethanol and deionized water at room temperature to obtain the treated carbon steel sheet for later use.

[0032] (2) Preparation of metal oxide nanoparticles A 2.5 wt% aqueous dispersion of ZrO2 was placed in a water bath at 70°C and stirred. Then, an alcoholic solution of 0.25 wt% KH-550 was slowly added dropwise. The mass ratio of ZrO2 to KH-550 was 10:1, and the addition was completed within 10 minutes. After stirring for 2 hours, the solution was filtered, washed, and dried in an oven at 80°C to obtain ZrO2 nanoparticle powder for later use.

[0033] (3) Preparation of hydrochloric acid-doped poly(o-methoxyaniline) / nano (POA / NPs) composite material HCl-doped POA-ZrO2 composite material was prepared by in-situ polymerization. ZrO2 nanoparticles were dispersed in a mixed solution of HCl and o-methoxyaniline monomer to form a suspension, with concentrations of HCl and o-methoxyaniline of 1 mol / L and 0.041 mol / L, respectively. The suspension was stirred in an ice-water bath at 0–5 °C for 30 min. Then, a 0.041 mol / L aqueous solution of ammonium persulfate was gradually added to the suspension over 15 min, with a molar ratio of o-methoxyaniline to ammonium persulfate of 1:1. After addition, stirring continued in the ice-water bath for 6 h to ensure complete polymerization, yielding a dark purple suspension. The obtained suspension was then filtered, washed, and dried at 80 °C for 24 h to obtain hydrochloric acid-doped POA / NPs composite material powder.

[0034] (4) Coating preparation Dry hydrochloric acid-doped POA / NPs composite powder was dispersed in a 1.5 mol / L NH3·H2O solution and stirred at room temperature for 6 h. After filtration, washing, and drying, dedoped POA / NPs composite powder was obtained. First, epoxy resin (EP) and PDMS were mixed at a mass ratio of 4:1 to obtain a mixture. Then, the dedoped POA / NPs composite powder was blended with the mixture at a mass ratio of 4:1 in a co-solvent consisting of 20 ml anhydrous ethanol and 0.5 ml N-methylpyrrolidone (NMP) to obtain a suspension. Finally, stearic acid was added, and the mixture was stirred in a 70°C water bath for 4 h to obtain a coating. The coating contained 9.27 wt% dedoped composite powder, 1.85 wt% epoxy resin, 0.46 wt% PDMS, and 11.59 wt% stearic acid. The prepared coating was then uniformly sprayed onto a treated carbon steel sheet using a spray gun. It is then dried at 50°C for 6 hours to form a coating.

[0035] Example 3 A method for preparing a corrosion-resistant and anti-icing superhydrophobic coating includes the following steps: (1) Pretreatment of carbon steel sheets The surface of the carbon steel sheet was polished with 400-5000 grit metallographic sandpaper until there were no obvious scratches. After polishing, the carbon steel sheet was ultrasonically cleaned with anhydrous ethanol and deionized water at room temperature to obtain the treated carbon steel sheet for later use.

[0036] (2) Preparation of metal oxide nanoparticles A 5 wt% aqueous dispersion of ZrO2 was placed in a water bath at 60°C and stirred. Then, a 1 wt% alcoholic solution of KH-550 was slowly added dropwise. The mass ratio of ZrO2 to KH-550 was 5:1. The addition was completed within 10 minutes. After stirring for 3 hours, the solution was filtered, washed, and dried in an oven at 80°C to obtain ZrO2 nanoparticle powder for later use.

[0037] (2) Preparation of hydrochloric acid-doped poly(o-methoxyaniline) / nano-(POA / NPs) composite materials: HCl-doped POA-ZrO2 composite material was prepared by in-situ polymerization. ZrO2 nanoparticles were dispersed in a mixed solution of HCl and o-methoxyaniline monomer to form a suspension, with concentrations of HCl and o-methoxyaniline of 1.5 mol / L and 0.08 mol / L, respectively. The suspension was stirred in an ice-water bath at 0–5 °C for 30 min. Then, a 0.1 mol / L aqueous solution of ammonium persulfate was gradually added to the suspension over 15 min, with a molar ratio of o-methoxyaniline to ammonium persulfate of 1:1.5. After addition, stirring was continued in the ice-water bath for 8 h to ensure complete polymerization, resulting in a dark purple suspension. The obtained suspension was then filtered, washed, and dried at 70 °C for 24 h to obtain hydrochloric acid-doped POA / NPs composite material powder.

[0038] (4) Coating preparation Dry hydrochloric acid-doped POA / NPs composite powder was dispersed in a 2 mol / L NH3·H2O solution and stirred at room temperature for 8 h. After filtration, washing, and drying, dedoped POA / NPs composite powder was obtained. First, epoxy resin (EP) and PDMS were mixed at a mass ratio of 4:1 to obtain a mixture. Then, the dedoped POA / NPs composite powder was mixed with the mixture at a mass ratio of 2:1 in a co-solvent consisting of 29.3 ml anhydrous ethanol and 0.7 ml N-methylpyrrolidone (NMP) to obtain a suspension. Finally, stearic acid was added, and the mixture was stirred in a water bath at 70°C for 6 h to obtain a coating. The coating contained 5.68 wt% dedoped composite powder, 2.27 wt% epoxy resin, 0.57 wt% PDMS, and 5.68 wt% stearic acid. The prepared coating was uniformly sprayed onto a treated carbon steel sheet using a spray gun. It was then dried at 60°C for 6 h to form a coating layer.

[0039] Example 4 A method for preparing a corrosion-resistant and anti-icing superhydrophobic coating includes the following steps: (1) Pretreatment of carbon steel sheets The surface of the carbon steel sheet was polished with 400-5000 grit metallographic sandpaper until there were no obvious scratches. After polishing, the carbon steel sheet was ultrasonically cleaned with anhydrous ethanol and deionized water at room temperature to obtain the treated carbon steel sheet for later use.

[0040] (2) Preparation of metal oxide nanoparticles A 6 wt% aqueous dispersion of ZrO2 was placed in a water bath at 60°C and stirred. Then, an alcoholic solution of 1.2 wt% KH-550 was slowly added dropwise. The mass ratio of ZrO2 to KH-550 was 5:1. The addition was completed within 10 minutes. After stirring for 2 hours, the solution was filtered, washed, and dried in an oven at 80°C to obtain ZrO2 nanoparticle powder for later use.

[0041] (2) Preparation of hydrochloric acid-doped poly(o-methoxyaniline) / nano-(POA / NPs) composite materials: HCl-doped POA-ZrO2 composite material was prepared by in-situ polymerization. ZrO2 nanoparticles were dispersed in a mixture of HCl and o-methoxyaniline monomer to form a suspension, with concentrations of HCl and o-methoxyaniline of 1 mol / L and 0.123 mol / L, respectively. The suspension was stirred in an ice-water bath at 0–5 °C for 30 min. Then, a 0.184 mol / L aqueous solution of ammonium persulfate was gradually added to the suspension over 15 min, with a molar ratio of o-methoxyaniline to ammonium persulfate of 1:1.5. After addition, stirring continued in the ice-water bath for 7 h to ensure complete polymerization, yielding a dark purple suspension. The obtained suspension was then filtered, washed, and dried at 65 °C for 24 h to obtain hydrochloric acid-doped POA / NPs composite material powder.

[0042] (4) Coating preparation Dry hydrochloric acid-doped POA / NPs composite powder was dispersed in a 2 mol / L NH3·H2O solution and stirred at room temperature for 10 h. After filtration, washing, and drying, dedoped POA / NPs composite powder was obtained. First, epoxy resin (EP) and PDMS were mixed at a mass ratio of 4:1 to obtain a mixture. Then, the dedoped POA / NPs composite powder was mixed with the mixture at a mass ratio of 1:1 in a co-solvent consisting of 39.1 ml anhydrous ethanol and 0.9 ml N-methylpyrrolidone (NMP) to obtain a suspension. Finally, myristic acid was added, and the mixture was stirred in a 70°C water bath for 6 h to obtain a coating. The coating contained 9.30 wt% dedoped composite powder, 7.43 wt% epoxy resin, 1.86 wt% PDMS, and 8.13 wt% myristic acid. The prepared coating was uniformly sprayed onto a treated carbon steel sheet using a spray gun. It is then dried at 45°C for 6 hours to form a coating.

[0043] Comparative Example 1 A method for preparing an unmodified coating includes the following steps: (1) Pretreatment of carbon steel sheets The surface of the carbon steel sheet was polished with 400-5000 grit metallographic sandpaper until there were no obvious scratches. After polishing, the carbon steel sheet was ultrasonically cleaned with anhydrous ethanol and deionized water at room temperature to obtain the treated carbon steel sheet for later use.

[0044] (2) Preparation of metal oxide nanoparticles A 2.5 wt% aqueous dispersion of ZrO2 was placed in a water bath at 70°C and stirred. Then, an alcoholic solution of 0.25 wt% KH-550 was slowly added dropwise. The mass ratio of ZrO2 to KH-550 was 10:1, and the addition was completed within 10 minutes. After stirring for 2 hours, the solution was filtered, washed, and dried in an oven at 80°C to obtain ZrO2 nanoparticle powder for later use.

[0045] (3) Preparation of hydrochloric acid-doped poly(o-methoxyaniline) / nano (POA / NPs) composite material HCl-doped POA-ZrO2 composite material was prepared by in-situ polymerization. ZrO2 nanoparticles were dispersed in a mixed solution of HCl and o-methoxyaniline monomer to form a suspension, with concentrations of HCl and o-methoxyaniline of 1 mol / L and 0.041 mol / L, respectively. The suspension was stirred in an ice-water bath at 0–5 °C for 30 min. Then, a 0.041 mol / L aqueous solution of ammonium persulfate was gradually added to the suspension over 15 min, with a molar ratio of o-methoxyaniline to ammonium persulfate of 1:1. After addition, stirring continued in the ice-water bath for 6 h to ensure complete polymerization, yielding a dark purple suspension. The obtained suspension was then filtered, washed, and dried at 80 °C for 24 h to obtain hydrochloric acid-doped POA / NPs composite material powder.

[0046] (4) Preparation of unmodified coating Dry hydrochloric acid-doped POA / NPs composite powder was dispersed in a 1.5 mol / L NH3·H2O solution and stirred at room temperature for 6 h. After filtration, washing, and drying, dedoped POA / NPs composite powder was obtained. First, epoxy resin (EP) and PDMS were mixed at a mass ratio of 4:1 to obtain a mixture. Then, the dedoped POA / NPs composite powder and the mixture were blended at a mass ratio of 4:1 in a co-solvent consisting of 20 ml anhydrous ethanol and 0.5 ml N-methylpyrrolidone (NMP). The mixture was stirred in a water bath at 70°C for 4 h to obtain a coating. The coating contained 9.27 wt% dedoped composite powder, 1.85 wt% epoxy resin, and 0.46 wt% PDMS. The prepared coating was uniformly sprayed onto a treated carbon steel sheet using a spray gun. It was then dried at 50°C for 6 h to form a coating layer.

[0047] The superhydrophobic coatings obtained in Example 2 and Comparative Example 1 were characterized, and their SEM images, as well as the surface contact angle and roll-off angle results of the superhydrophobic coating obtained in Example 2, are shown in the figure. Figure 1It can be seen that: the surface morphology of the coating obtained in Comparative Example 1 is an irregular gravel-like mixed particle stacking structure, which is hydrophilic; the surface morphology of the superhydrophobic coating obtained in Example 2 is a sheet-like mixed particle stacking structure, which is superhydrophobic and its surface contact angle is 164° and its roll-off angle is 6.1°.

[0048] The superhydrophobic coating obtained in Example 2 was subjected to EDS testing, and the results are shown in [Figure 2]. Figure 2 It can be seen that the coating surface obtained in Example 2 contains C, O, N, and Zr elements. Therefore, it can be determined that stearic acid is grafted onto the coating surface.

[0049] The icing performance of the superhydrophobic coating obtained in Example 2 was tested under a cooling stage temperature of -15°C. The results are shown in [Figure 2]. Figure 3 It can be seen that the freezing time of the superhydrophobic coating obtained in Example 2 is 676 seconds, which significantly prolongs the freezing time of water droplets on the material compared with the bare carbon steel sheet, indicating that the superhydrophobic coating obtained by the present invention has excellent anti-icing performance.

[0050] Electrochemical corrosion tests were conducted on the superhydrophobic coating (SPZC coating) obtained in Example 2 in a 3.5% NaCl solution to evaluate its corrosion resistance. The results are shown in [Figure number missing]. Figure 4 It can be seen that the corrosion potential of the SPZC coating is -323 mV, which is significantly positively shifted compared with the bare carbon steel sheet (CS, -685 mV); at the same time, the corrosion current of the SPZC coating is significantly reduced, and the protection efficiency of the superhydrophobic coating is 99.4%.

Claims

1. A method for preparing a corrosion-resistant and anti-icing superhydrophobic coating, characterized in that: Includes the following steps: (1) Disperse metal oxide nanoparticle powder in a blend solution containing hydrochloric acid and o-methoxyaniline monomer to obtain a suspension; place it in an ice-water bath and stir to react, then slowly add ammonium persulfate aqueous solution, continue stirring to react in an ice-water bath to obtain a black-purple suspension; filter, wash, and dry to obtain hydrochloric acid doped POA / NPs composite material; (2) The hydrochloric acid-doped POA / NPs composite material obtained in step (1) is dispersed in an ammonia solution, stirred at room temperature, filtered, washed, and dried to obtain dedoped POA / NPs composite powder; it is then mixed with epoxy resin and polydimethylsiloxane in a blended solvent of anhydrous ethanol and N-methylpyrrolidone, followed by the addition of fatty acids, and the reaction is carried out by water bath heating and stirring to obtain a coating; finally, the coating is uniformly sprayed onto the substrate and dried to obtain a superhydrophobic coating that is corrosion-resistant and anti-icing.

2. The preparation method according to claim 1, characterized in that: In step (1), the metal oxide nanoparticles are either zirconium oxide nanoparticles or titanium oxide nanoparticles.

3. The preparation method according to claim 1, characterized in that: In step (2), the fatty acid is one or more of stearic acid or myristic acid.

4. The preparation method according to claim 1, characterized in that: In step (1), the metal oxide nanoparticles are prepared by the following method: an aqueous dispersion of the metal oxide is placed in a water bath at 45-70°C and stirred in the water bath, and then an alcoholic solution of γ-aminopropyltriethoxysilane is slowly added dropwise over 5-20 minutes. After stirring continuously for 2-4 hours, the nanoparticles are filtered, washed, and dried to obtain the final product. The mass ratio of the metal oxide to γ-aminopropyltriethoxysilane is 5-10:

1.

5. The preparation method according to claim 1, characterized in that: In step (1), the solid-liquid ratio of the metal oxide nanoparticle powder to the blend solution is 1:5-20; the molar ratio of o-methoxyaniline to ammonium persulfate is 1:1-1.5; in the blend solution, the concentration of hydrochloric acid is 0.3-2 mol / L and the concentration of o-methoxyaniline is 0.02-0.3 mol / L.

6. The preparation method according to claim 1, characterized in that: In step (1), the suspension is placed in an ice-water bath at 0-5℃ and stirred for 15-40 min. Then, ammonium persulfate aqueous solution is slowly added dropwise. The entire addition process is completed within 15-20 min. The suspension is stirred and reacted in the ice-water bath for 6-8 h to obtain a blackish-purple suspension. The suspension is then filtered, washed, and dried at 60-80℃ for 24 h to obtain hydrochloric acid-doped POA / NPs composite material.

7. The preparation method according to claim 1, characterized in that: In step (2), the solid-liquid ratio of the hydrochloric acid-doped POA / NPs composite material to the ammonia solution is 1:5-25, and the concentration of the ammonia solution is 0.8-3 mol / L; in the coating, the mass fraction of the dedoped POA / NPs composite powder is 1-35 wt%, the mass fraction of the epoxy resin is 1-25 wt%, the mass fraction of the polydimethylsiloxane is 1-6 wt%, and the mass fraction of the fatty acid is 1-15 wt%; in the blending solvent, the volume ratio of anhydrous ethanol to N-methylpyrrolidone is 20-40:

1.

8. The preparation method according to claim 1, characterized in that: In step (2), the room temperature stirring reaction time is 6-8 h; the water bath stirring conditions are 4-6 h at 60-70℃; and the drying conditions are 6-10 h at 40-60℃.

9. The anti-corrosion and anti-icing superhydrophobic coating prepared by the method according to any one of claims 1 to 8, characterized in that: The superhydrophobic coating has a water contact angle of 152.4°~161.2° and a roll-off angle of 4.3°~6.2°.

10. The application of the anti-corrosion and anti-icing superhydrophobic coating of claim 9 in the preparation of integrated protective materials for marine engineering and / or wind power generation.

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