Self-healing super-hydrophobic corrosion-resistant composite coating and preparation method and application thereof

Abstract

The present application belongs to the technical field of super-hydrophobic material surface modification, and particularly relates to a self-healing super-hydrophobic corrosion-resistant composite coating, a preparation method and application thereof. The preparation method comprises the following steps: mixing bisphenol A diglycidyl ether, neopentyl glycol diglycidyl ether, polyether amine, microcrystalline wax emulsion and KH560 modified CeO2 to obtain a self-healing epoxy coating; mixing perfluorodecanethiol, octavinyl cage silsesquioxane and a photoinitiator, carrying out thiol-ene click reaction, and then mixing with an ethanol solution to obtain a super-hydrophobic coating; and depositing the super-hydrophobic coating on the self-healing epoxy coating to obtain a self-healing super-hydrophobic corrosion-resistant composite coating. The self-healing super-hydrophobic corrosion-resistant composite coating has multi-environmental response self-healing super-hydrophobic corrosion-resistant performance, not only overcoming the problem that traditional corrosion-resistant coatings are prone to corrosion after damage, but also solving the problems that existing super-hydrophobic coatings have poor durability, limited self-repairing capacity, and shape memory coatings are prone to failure in a corrosive environment.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of electrochemistry, in particular to a self-healing super-hydrophobic corrosion-resistant composite coating and a preparation method and application thereof. BACKGROUND

[0002] Corrosion exists in all fields of the national economy, from daily life to industrial and agricultural production, from cutting-edge technology to national defense industry, wherever materials are used. Using polymer protective coatings to protect the substrate is one of the most widely used technologies in material corrosion protection. Traditional organic corrosion-resistant coatings are widely used in the field of corrosion protection due to their good compactness, which can isolate corrosive media from contact with metal. However, coating damage can lead to direct contact between corrosive media and the surface of the substrate, and with the passage of time, the electrolyte solution will penetrate the coating to reach the metal substrate, resulting in corrosion.

[0003] The micro-nano structure of the biomimetic super-hydrophobic surface can capture a layer of air between the coating and the corrosive medium, thereby effectively reducing the contact area and contact time of the coating and the corrosive medium. However, most super-hydrophobic coatings are easily damaged by physical scratching or even gentle finger touch, which leads to the loss of super-hydrophobicity and the protective air cushion at the solid-liquid interface. By enhancing the inherent durability of the super-amphiphobic coating or endowing the super-hydrophobic coating with self-healing ability, the super-hydrophobicity can be maintained without damage.

[0004] It is well known that self-repairing super-hydrophobic coatings are rarely seen, mainly constructed on fabrics. A common strategy for making self-repairing super-hydrophobic coatings is to introduce self-repairing agents into the coating. Once the coating is damaged, the self-healing agent is released and repairs the damage. This self-healing strategy is suitable for chemical damage, but is usually ineffective for physical damage, because the release of the self-healing agent cannot repair micron or nanometer structure damage.

[0005] In addition, the introduction of self-healing agents affects the inherent properties of super-hydrophobic coatings. Shape memory polymer coatings have good compactness and can recover their original shape under heating conditions after being deformed by external force, thus having self-healing ability for physical damage, and are therefore widely used in many fields, including corrosion protection of metal alloys. However, this single shape memory polymer coating is inherently hydrophilic and has a small porosity. When the shape memory polymer coating comes into contact with corrosive media such as seawater, the corrosive media can penetrate into the interior of the coating through the voids, and then come into contact with the protected metal substrate. Although it can provide protection in the short term, over time, it will still cause the metal to suffer serious corrosion. SUMMARY

[0006] In view of the problems existing in the prior art, the self-healing super-hydrophobic corrosion-resistant composite coating and a preparation method and application thereof are provided.The self-healing super-hydrophobic corrosion-resistant composite coating is prepared by using bisphenol A diglycidyl ether, neopentyl glycol diglycidyl ether, polyether amine, microcrystalline wax emulsion and KH560 modified CeO2 as raw materials, and adopting a blending method to obtain a self-healing epoxy coating; a mixture of perfluorodecanethiol and octavinylsilsesquioxane is subjected to a thiol-ene click reaction under the action of a photoinitiator to obtain a super-hydrophobic coating; and finally, the self-healing epoxy coating is immersed in the super-hydrophobic coating to obtain the self-healing super-hydrophobic corrosion-resistant composite coating.The self-healing super-hydrophobic corrosion-resistant composite coating has the performance of multi-environmental response, self-healing, super-hydrophobicity, self-cleaning and corrosion resistance, overcomes the problem that a traditional anticorrosive coating is prone to causing corrosion medium penetration after damage, and solves the problems of poor physical durability of an existing super-hydrophobic coating, limited self-repairing capacity and easy failure of a shape memory polymer coating in a long-time corrosion environment.

[0007] In order to achieve the above-mentioned purpose, the technical scheme adopted by the present application is:

[0008] The first object of the present application is to provide a preparation method of a self-healing super-hydrophobic corrosion-resistant composite coating, comprising the following steps:

[0009] S1, cleaning the substrate to remove surface grease, floating dust and other pollutants, and then drying to obtain a pretreated substrate.

[0010] S2, preparation of the self-healing epoxy coating:

[0011] The silane coupling agent KH560 suspension liquid is mixed with CeO2 to perform a substitution reaction to obtain KH560 modified CeO2; the silane coupling agent KH560 contains glycidyl ether bonds and three methoxy groups, the methoxy groups can hydrolyze and substitute the hydroxyl groups on the surface of CeO2, and endow the CeO2 with glycidyl ether bonds, and the bisphenol A diglycidyl ether also contains glycidyl ether bonds, according to the principle of similarity and compatibility, the CeO2 doped with the same groups has better compatibility and can better play the performance.

[0012] The shape memory polymer bisphenol A diglycidyl ether, the diluent neopentyl glycol diglycidyl ether, the crosslinking agent polyether amine, the microcrystalline wax emulsion and the KH560 modified CeO2 are mixed, the bisphenol A diglycidyl ether and the neopentyl glycol diglycidyl ether are subjected to epoxy ring-opening reaction through the amine groups of the polyether amine to gradually form a crosslinking network, and are mixed uniformly with the microcrystalline wax emulsion and the KH560 modified CeO2, the synergistic effect of the two kinds of epoxy resins and the crosslinking action of the polyether amine together improve the mechanical properties of the self-healing epoxy coating, finally a stable three-dimensional thermosetting network structure is formed, and the self-healing epoxy coating is obtained.

[0013] S3, preparation of the super-hydrophobic coating:

[0014] The perfluorodecanethiol, octavinylsilsesquioxane and photoinitiator 2,2-dimethoxy-2-phenylacetophenone are mixed, and a thiol-ene click reaction is carried out under the action of the photoinitiator to obtain fluorinated vinylsilsesquioxane nanoparticles.

[0015] The fluorinated vinylsilsesquioxane nanoparticles are mixed with an ethanol solution to obtain a super-hydrophobic coating.

[0016] S4, preparation of a self-healing super-hydrophobic corrosion-resistant composite coating:

[0017] After the self-healing epoxy coating is applied, curing treatment is performed to form a self-healing epoxy coating; a super-hydrophobic coating is deposited on the self-healing epoxy coating, and drying treatment is performed, and under the action of a photoinitiator, addition reaction occurs between the epoxy matrix of the bottom layer self-healing epoxy coating and the vinyl matrix of the surface layer super-hydrophobic coating to obtain a self-healing super-hydrophobic corrosion-resistant composite coating.

[0018] Preferably, the mass ratio of bisphenol A diglycidyl ether, neopentyl glycol diglycidyl ether, polyether amine, microcrystalline wax emulsion and KH560 modified CeO2 is 1-10:1-10:1-10:10-100:10-100; the bisphenol A diglycidyl ether is a thermoplastic epoxy resin, which plays a key role in the thermal field self-healing performance, the neopentyl glycol diglycidyl ether is a diluent, and the polyether amine is a crosslinking agent, and an equimolar ratio can fully play the effect of each component to form an effective crosslinked network structure; the amount of KH560 modified CeO2 is obtained by experiment, and under this amount, the corrosion protection performance of the self-healing super-hydrophobic corrosion-resistant composite coating is greatly improved; if the amount of KH560 modified CeO2 is too small, the corrosion protection performance of the self-healing super-hydrophobic corrosion-resistant composite coating is not obviously improved, and the self-healing performance of CeO2 itself cannot be played; if the amount of KH560 modified CeO2 is too much, the self-healing performance of the epoxy resin and the corrosion protection performance of the self-healing super-hydrophobic corrosion-resistant composite coating will be affected.

[0019] Preferably, the mass ratio of perfluorodecanethiol, octavinylsilsesquioxane and 2,2-dimethoxy-2-phenylacetophenone is 3-150:1-50:0.1-5; perfluorodecanethiol is used as a fluorinated modifier to provide low surface energy, and octavinylsilsesquioxane particles are endowed with superhydrophobic properties; under this ratio, the eight vinyl functional groups of octavinylsilsesquioxane can be completely subjected to thiol-ene click reaction to provide optimal grafting effect; too much perfluorodecanethiol will float on the surface, and because of too low surface energy and too much residual amount, octavinylsilsesquioxane will be bonded and agglomerated; too little perfluorodecanethiol cannot complete effective thiol-ene click reaction, and cannot provide effective hydrophobic properties; 2,2-dimethoxy-2-phenylacetophenone is used as a photoinitiator, and its content should not be too high; it can promote the occurrence of substitution reaction, but will not be consumed, and after reaction, it will be mixed with fluorinated vinyl silsesquioxane nanoparticles, and is not easy to remove.

[0020] Preferably, the conditions of thiol-ene click reaction are as follows: under ultraviolet lamp irradiation, reaction is carried out at 10-30℃ for 0.5-2h. Thiol-ene click reaction is usually carried out in a relatively mild environment, and the solvent is dichloromethane, which is easily volatile, and its boiling point is 39℃; if the temperature is too high, the solvent will be too fast to volatilize, and the reaction will not be carried out; if the temperature is too low, the reaction rate will be slow, and 0.5-2h is a relatively ideal reaction time obtained by experiment; too short reaction time will result in incomplete reaction, and cannot form effective superhydrophobic coating; long time exposure to ultraviolet light will induce other side reactions, such as oxidation of thiol to disulfide or polymerization of ethylene, which will affect the purity and yield of fluorinated vinyl silsesquioxane nanoparticles; meanwhile, long reaction time will consume more energy, cause light source to age or be damaged, and increase maintenance cost.

[0021] Preferably, the silane coupling agent KH560 suspension is prepared according to the following steps:

[0022] The silane coupling agent KH560, γ-glycidoxypropyltrimethoxysilane and n-butanol are mixed to obtain the silane coupling agent KH560 suspension; in the silane coupling agent KH560 suspension, the mass concentration of γ-glycidoxypropyltrimethoxysilane is 10-100g / L.

[0023] Preferably, the mass-volume ratio of silane coupling agent KH560 and CeO2 is 1-5:2-10; this concentration range is relative to CeO2; too high concentration of silane coupling agent KH560 will result in too much residual amount which has not been grafted with CeO2, and will affect the performance of self-healing superhydrophobic corrosion-resistant composite coating; too low concentration of silane coupling agent KH560 will result in poor grafting effect, and CeO2 will not be dispersed enough, and will be easily agglomerated, which will affect the performance of self-healing superhydrophobic corrosion-resistant composite coating.

[0024] Preferably, the addition reaction is dry at room temperature under light.

[0025] Preferably, in the preparation of the self-healing epoxy coating, the conditions of the substitution reaction are: drying at 80-150℃ for 1-6h; since the boiling point of n-butanol is 76℃, it is not easy to volatilize at room temperature, so if the temperature is too low, n-butanol cannot volatilize and dry; if the temperature is too high, it will affect the stability of the fluorinated modified chain and the performance of the self-healing super-hydrophobic corrosion-resistant composite coating. If the temperature is too high, the fluorinated molecular modified chain segment of octa-vinyl cage silsesquioxane is prone to thermal degradation, leading to molecular chain rupture, resulting in loss of super-hydrophobic performance of the coating. In the experimental test, this phenomenon is true, and the thermal stability is not more than 150℃.

[0026] Preferably, the microcrystalline wax emulsion is prepared according to the following steps:

[0027] The microcrystalline wax is melted and mixed with the dispersant to obtain a microcrystalline wax emulsion; wherein the mass ratio of microcrystalline wax to sodium dodecyl benzene sulfonate is 10-100:1-10; sodium dodecyl benzene sulfonate, as a commonly used dispersant, can improve the dispersibility of microcrystalline wax; too much dispersant will increase its proportion in the self-healing super-hydrophobic corrosion-resistant composite coating, making the dispersion effect of the self-healing epoxy coating worse and affecting the comprehensive performance of the self-healing super-hydrophobic corrosion-resistant composite coating; too little dispersant will make the microcrystalline wax easy to form a group after cooling, which is not conducive to the corrosion protection of the self-healing super-hydrophobic corrosion-resistant composite coating.

[0028] Preferably, the curing treatment conditions are: curing at 25-60℃ for 2-48h; the self-healing epoxy coating is in a condensed flow state, and after curing treatment, the cohesion of the self-healing epoxy coating is released to ensure its protective performance; the glass transition temperature of the self-healing epoxy coating is 60℃, and if the temperature is too high or the curing time is too short, the cohesion of the self-healing epoxy coating cannot be completely released, which not only affects the performance of the self-healing epoxy coating, but also causes the self-healing epoxy coating to peel off due to too high cohesion; if the temperature is too low, the self-healing epoxy coating cannot be cured.

[0029] Preferably, the mass-volume ratio of fluorinated ethenyl cage silsesquioxane nanoparticles to ethanol solution is 1g-10g:10mL-100mL.

[0030] Preferably, the thickness of the self-healing epoxy coating is 5-2000μm; if the thickness is too low, neither the protection nor the self-healing performance can be achieved; if the thickness is too much, the self-healing epoxy coating is prone to peeling off due to too high cohesion.

[0031] Preferably, the drying treatment conditions are: drying at room temperature for 0.5-1h.

[0032] Preferably, the substrate is selected from metal, ceramic, cement, concrete or fabric.

[0033] Preferably, the coating method is selected from spraying, dipping or doctor blading.

[0034] A second object of the present application is to provide a self-healing super-hydrophobic corrosion-resistant composite coating prepared by the above preparation method.

[0035] A third object of the present application is to provide the use of the above self-healing super-hydrophobic corrosion-resistant composite coating in the preparation of fabric corrosion inhibitors, ice-repellent agents or self-cleaning agents.

[0036] Compared with the prior art, the present application has the following advantages:

[0037] 1. The present application provides a preparation method of a self-healing super-hydrophobic corrosion-resistant composite coating. A silane coupling agent KH560 suspension solution is mixed with CeO2 to perform a substitution reaction to obtain KH560 modified CeO2. A shape memory polymer bisphenol A diglycidyl ether, a diluent neopentyl glycol diglycidyl ether, a crosslinking agent polyether amine, a microcrystalline wax emulsion composed of microcrystalline wax and sodium dodecyl benzene sulfonate, and the sodium dodecyl benzene sulfonate as a dispersant are mixed with the KH560 modified CeO2. The bisphenol A diglycidyl ether and the neopentyl glycol diglycidyl ether initiate an epoxy ring-opening reaction through the amine group of the polyether amine to gradually form a crosslinked network to obtain a self-healing epoxy coating, which is then mixed uniformly with the microcrystalline wax emulsion and the KH560 modified CeO2 to obtain a self-healing epoxy coating. Perfluorodecanethiol, octavinylsilsesquioxane and a photoinitiator 2,2-dimethoxy-2-phenylphenylacetophenone are mixed to perform a thiol-ene click reaction under the action of the photoinitiator to obtain fluorinated ethenylsilsesquioxane nanoparticles. The fluorinated ethenylsilsesquioxane nanoparticles are mixed with an ethanol solution to obtain a super-hydrophobic coating. After the self-healing epoxy coating is applied, a curing treatment is performed to form a self-healing epoxy coating. After the self-healing epoxy coating is applied, a curing treatment is performed to form a self-healing epoxy coating. The super-hydrophobic coating is deposited on the self-healing epoxy coating, and after drying treatment, an addition reaction occurs between the epoxy matrix of the bottom layer self-healing epoxy coating and the ethylene matrix of the surface layer super-hydrophobic coating under the action of the photoinitiator to obtain a self-healing super-hydrophobic corrosion-resistant composite coating. The self-healing super-hydrophobic corrosion-resistant composite coating of the present application has the performance of multi-environmental response self-healing super-hydrophobic self-cleaning corrosion resistance, not only overcoming the problem that traditional corrosion-resistant coatings are easily penetrated by corrosion media after damage, but also solving the problems of poor physical durability (poor corrosion resistance) of existing super-hydrophobic coatings, limited self-repairing ability, single repair mode, and easy failure of shape memory polymer coatings exposed to corrosive environments for a long time (poor acid, alkali and salt resistance).

[0038] 2、The self-healing epoxy coating is prepared by using bisphenol A diglycidyl ether as a shape memory polymer and doping KH560 modified CeO2 with good dispersibility through a blending method. 2+ react with OH - in the environment to form Ce(OH) 3+ or Ce(OH) 4+ with excellent corrosion resistance, and form a protective film, thereby endowing the self-healing super-hydrophobic corrosion-resistant composite coating with the ability of self-repairing in a hot field and a corrosive medium after damage.

[0039] 3、In the self-healing super-hydrophobic corrosion-resistant composite coating, the self-healing epoxy coating serves as a bottom layer, and the super-hydrophobic coating serves as a top layer. Under the action of a photoinitiator, the epoxy matrix composed of bisphenol A diglycidyl ether and neopentyl glycol diglycidyl ether in the bottom layer and the vinyl matrix of fluorinated vinyl cage silsesquioxane in the top layer undergo addition reaction. This reaction causes the two to be tightly combined through ether bonds (-O-CH2-CH2-), thereby forming high-strength interfacial bonding force. This combination mode of the bottom layer and the top layer not only enhances the overall strength of the material, but also realizes performance improvement through synergistic effect, that is, 1+1>2. When the bottom layer coating heals itself, it can drive the movement of the top layer coating, thereby restoring the super-hydrophobic performance of the damaged part. In particular, the three healing mechanisms of the self-healing super-hydrophobic corrosion-resistant composite coating can be triggered at the same time, so that the self-healing super-hydrophobic corrosion-resistant composite coating has excellent performances of multi-environmental response self-healing, super-hydrophobicity and self-cleaning, can realize synchronous repair of low-surface-energy substances and surface rough structures, can maintain effective corrosion resistance even after long-term immersion in a harsh acid-alkali-salt corrosion environment, and can realize self-healing after chemical damage and mechanical damage.

[0040] 3、The preparation method of the self-healing super-hydrophobic corrosion-resistant composite coating is simple in process and high in economic benefits.

[0041] 4. The self-healing super-hydrophobic corrosion-resistant composite coating prepared by the application is applied to a fabric, the surface of the fabric is in situ grafted with octavinyl cage silsesquioxane particles with nano-papillary structure, and after modification by a vinyl-terminated polydimethylsiloxane, the water contact angle of the fabric in air is greater than 150°, the rolling angle is less than 10°, the fabric has a self-healing property, excellent super-hydrophobicity, and corrosion resistance to acid, alkali and salt, and can be applied to the fields of ice suppression, ice prevention and self-cleaning in addition to the field of substrate surface corrosion prevention. BRIEF DESCRIPTION OF DRAWINGS

[0042] Figure 1 The surface morphology diagrams of SHEP, SHEP+KH560-CeO2, FPOSS, SHEP+KH560-CeO2+FPOSS prepared in Example 1, wherein a is SHEP, b is SHEP+KH560-CeO2, c is FPOSS, and d is SHEP+KH560-CeO2+FPOSS.

[0043] Figure 2 The contact angle result diagram of SHEP+KH560-CeO2+FPOSS in Example 1.

[0044] Figure 3 The self-healing performance result diagram of SHEP+KH560-CeO2+FPOSS prepared in Example 1, wherein a is before scratch healing, and b is after scratch healing.

[0045] Figure 4 The long-term corrosion resistance result diagram of SHEP+KH560-CeO2 prepared in Example 1, wherein a is the impedance modulus curve during long-term immersion in 3.5% NaCl, b is the dynamic polarization curve during long-term immersion in 3.5% NaCl, c is the impedance modulus curve during long-term immersion in 1 mol / L NaOH, and d is the dynamic polarization curve during long-term immersion in 1 mol / L NaOH.

[0046] Figure 5 The long-term corrosion resistance result diagram of SHEP+KH560-CeO2+FPOSS prepared in Example 1, wherein a is the impedance modulus curve during long-term immersion in 3.5% NaCl, b is the phase angle diagram during long-term immersion in 3.5% NaCl, c is the dynamic polarization curve during long-term immersion in 3.5% NaCl, d is the impedance modulus curve during long-term immersion in 1 mol / L NaOH, e is the phase angle diagram during long-term immersion in 1 mol / L NaOH, and f is the dynamic polarization curve during long-term immersion in 1 mol / L NaOH.

[0047] Figure 6Figure for long-term corrosion protection performance results of SHEP+KH560-CeO2+FPOSS in Example 1, wherein a is the impedance modulus curve in 3.5% NaCl long-term immersion, b is the phase angle plot in 3.5% NaCl long-term immersion, c is the dynamic polarization curve in 3.5% NaCl long-term immersion, d is the impedance modulus curve in 1 mol / L NaOH long-term immersion, e is the phase angle plot in 1 mol / L NaOH long-term immersion, and f is the dynamic polarization curve in 1 mol / L NaOH long-term immersion. DETAILED DESCRIPTION

[0048] The technical solutions of the present application will be clearly and completely described below in combination with the data in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0049] It should be noted that the professional terms used in the present application are only for the purpose of describing the specific embodiments and are not intended to limit the scope of protection of the present application. Unless otherwise specified, the various raw materials, reagents, instruments and equipment used in the following embodiments of the present application can be purchased from the market or prepared by the existing method. Among them, γ-glycidyl ether oxypropyl trimethoxysilane is denoted as KH560; cerium dioxide is denoted as CeO2; bisphenol A diglycidyl ether is denoted as BADGE; neopentyl glycol diglycidyl ether is denoted as NGDE; polyetheramine is denoted as D230; octavinyl cage silsesquioxane is denoted as OVPOSS; 2,2-dimethoxy-2-phenylacetophenone is denoted as DMPA.

[0050] In the prior art, although polymer protective coatings and biomimetic superhydrophobic surfaces have achieved certain results in material corrosion protection, there are still many technical defects. Although the traditional organic anticorrosive coating has good compactness and can effectively isolate the corrosive medium from contacting the metal, once the coating is damaged, the corrosive medium will directly contact the substrate surface, leading to corrosion. Although the biomimetic superhydrophobic surface can reduce the contact area and time with the corrosive medium by capturing an air layer through micro-nano structures, it has poor physical durability and is easily scratched or even damaged by slight touch, thereby losing the superhydrophobic performance and protective air cushion. In addition, self-repairing superhydrophobic coatings are rare and are mainly constructed on fabrics, and the self-healing strategy is usually ineffective for physical damage, and the introduced self-healing reagents affect the inherent properties of the coating. Although the shape memory polymer coating has self-healing ability for physical damage, the single shape memory polymer coating itself has hydrophilicity and porosity, and will gradually fail under long-term immersion of corrosive medium, leading to serious corrosion of the metal.

[0051] In order to overcome the above technical defects, the present application provides a preparation method of a self-healing super-hydrophobic corrosion-resistant composite coating, comprising the following steps: mixing a silane coupling agent KH560 suspension solution with CeO2 to carry out a substitution reaction to obtain KH560 modified CeO2; mixing a shape memory polymer bisphenol A diglycidyl ether, a diluent neopentyl glycol diglycidyl ether, a crosslinking agent polyether amine, a microcrystalline wax emulsion and the KH560 modified CeO2, the bisphenol A diglycidyl ether and the neopentyl glycol diglycidyl ether being initiated to carry out an epoxy ring-opening reaction through the amine group of the polyether amine to gradually form a crosslinking network, and being mixed with the microcrystalline wax emulsion and the KH560 modified CeO2 to be uniform to obtain a self-healing epoxy coating; mixing perfluorodecanethiol, octavinyl cage silsesquioxane and a photoinitiator 2,2-dimethoxy-2-phenylphenylacetophenone to carry out a thiol-alkene click reaction under the action of the photoinitiator to obtain fluorinated ethenyl cage silsesquioxane nanoparticles; mixing the fluorinated ethenyl cage silsesquioxane nanoparticles with an ethanol solution to obtain a super-hydrophobic coating; after the self-healing epoxy coating is coated, carrying out a curing treatment to form a self-healing epoxy coating layer; depositing the super-hydrophobic coating on the self-healing epoxy coating layer, and carrying out a drying treatment, under the action of the photoinitiator, an addition reaction occurs between the epoxy matrix of the bottom layer self-healing epoxy coating and the ethylene matrix of the surface layer super-hydrophobic coating to obtain a self-healing super-hydrophobic corrosion-resistant composite coating.

[0052] The self-healing super-hydrophobic corrosion-resistant composite coating has the performance of multi-environmental response self-healing super-hydrophobic self-cleaning corrosion resistance, and the super-hydrophobic coating prepared by mixing the fluorinated ethenyl cage silsesquioxane nanoparticles with the ethanol solution in the present application can effectively block the contact between the self-healing epoxy coating and the corrosive medium, thereby avoiding the corrosion of the metal substrate. The present application not only overcomes the problem that the traditional anti-corrosion coating is easy to cause the penetration of corrosive medium after damage, but also solves the problems of poor physical durability, limited self-repairing ability, single repair mode of the existing super-hydrophobic coating, and easy failure of the shape memory polymer coating exposed to the corrosive environment for a long time.

[0053] In order to enable those skilled in the art to more clearly understand the technical solutions of the present application, the technical solutions of the present application will be described in detail below in combination with specific examples.

[0054] Example 1

[0055] A preparation method of a self-healing super-hydrophobic corrosion-resistant composite coating, comprising the following steps:

[0056] S1, cleaning the magnesium alloy substrate to remove surface grease, floating dust and other pollutants, and then drying to obtain a pretreated substrate.

[0057] S2, preparation of a self-healing epoxy coating:

[0058] 3.5 g of KH560 was added into a mixed solution prepared from 45 g of n-butanol and 5 g of deionized water, and magnetically stirred for 30 min to obtain a suspension of KH560 with a concentration of 70 g / L. Then, 5 g of CeO2 was added into the suspension, and magnetically stirred for another 30 min. After that, the suspension was dried at 80 °C for 6 h to obtain KH560-modified CeO2.

[0059] After 1 g, 10 g / L of microcrystalline wax was hot-melted at 80 °C, 0.1 g, 1 g / L of sodium dodecyl benzene sulfonate was added, and magnetically stirred for 10 min to form a microcrystalline wax emulsion. Meanwhile, equal molar amounts of 4.56 g of BADGE, 2.96 g of NGDE, 2.55 g of D230 and the microcrystalline wax emulsion were mixed by magnetic stirring to obtain a clear solution, which was denoted as SHEP. 1 g, 50 g / L of KH560-modified CeO2 was added into the clear solution, and magnetically stirred for 30 min to obtain a self-healing epoxy coating, which was denoted as SHEP+KH560-CeO2, and was ready for use.

[0060] S3, Preparation of a superhydrophobic coating:

[0061] After 0.3 g, 30 g / L of perfluorodecanethiol was added into a dichloromethane solution of 1 g, 10 g / L of OVPOSS and 0.1 g, 1 g / L of DMPA, and irradiated under a UV lamp for 15 min, the fluorinated ethenyl cage silsesquioxane nanoparticles, i.e. FPOSS nanoparticles, were obtained by washing with dichloromethane and drying. The FPOSS nanoparticles were added into an ethanol solution, and ultrasonically treated for 20 min to obtain a superhydrophobic coating, which was denoted as FPOSS, and was ready for use.

[0062] S4, Preparation of a self-healing superhydrophobic corrosion-resistant composite coating:

[0063] The self-healing epoxy coating was coated onto the pretreated substrate and cured at 50 °C for 24 h to form a self-healing epoxy coating, i.e. a bottom layer coating, with a thickness of 100 μm. Then, 20 g / L of FPOSS was coated onto the substrate, and dried under light at room temperature to obtain a self-healing superhydrophobic corrosion-resistant composite coating, which was denoted as SHEP+KH560-CeO2+FPOSS.

[0064] Example 2

[0065] A method for preparing a self-healing superhydrophobic corrosion-resistant composite coating, comprising the following steps:

[0066] S1, The magnesium alloy substrate was cleaned to remove surface grease, floating dust and other contaminants, and then dried to obtain a pretreated substrate.

[0067] S2, Preparation of a self-healing epoxy coating:

[0068] 2g of KH560 was added into a mixed solution of 40g of n-butanol and 10g of deionized water, and magnetically stirred for 30min to obtain a suspension of KH560 with a concentration of 40g / L. Then, 3g of CeO2 was added into the suspension, and magnetically stirred for another 10min. The mixture was dried at 90°C for 5h to obtain KH560-modified CeO2.

[0069] 3g of microcrystalline wax with a concentration of 30g / L was hot-melted at 85°C, and 0.3g of sodium dodecyl benzene sulfonate with a concentration of 3g / L was added into the hot-melted microcrystalline wax, and magnetically stirred for 5min to form a microcrystalline wax emulsion. Meanwhile, equal molar amounts of 13.68g of BADGE, 8.88g of NGDE, 7.68g of D230 and the microcrystalline wax emulsion were mixed by magnetic stirring to obtain a clear solution, which was denoted as SHEP. 1g of KH560-modified CeO2 with a concentration of 50g / L was added into the clear solution, and magnetically stirred for 60min to obtain a self-healing epoxy coating, which was denoted as SHEP+KH560-CeO2, and was ready for use.

[0070] S3, Preparation of a super-hydrophobic coating:

[0071] 0.3g of perfluorodecanethiol with a concentration of 3g / L was added into a dichloromethane solution of 1g of OVPOSS with a concentration of 1g / L and 0.1g of DMPA with a concentration of 0.1g / L, and irradiated under a UV lamp for 10min. After that, the FPOSS nanoparticles were obtained by washing with dichloromethane and drying. The FPOSS nanoparticles were added into an ethanol solution, and ultrasonically treated for 10min to obtain a super-hydrophobic coating, which was denoted as FPOSS, and was ready for use.

[0072] S4, Preparation of a self-healing super-hydrophobic corrosion-resistant composite coating:

[0073] The self-healing epoxy coating was coated onto a pretreated substrate and cured at 25°C for 48h to form a self-healing epoxy coating, i.e., a bottom layer coating, with a thickness of 5μm. Then, 5g / L of FPOSS was coated onto the substrate, and dried under light irradiation at room temperature to obtain a self-healing super-hydrophobic corrosion-resistant composite coating, which was denoted as SHEP+KH560-CeO2+FPOSS.

[0074] The contact angle of a 3.5% NaCl water droplet on the surface of the prepared SHEP+KH560-CeO2+FPOSS was 168°, indicating that the surface of the prepared fabric had super-hydrophobicity. The initial impedance modulus of the coating was 2.21×10 -10 Ω, the phase angle was -8.39, the corrosion voltage was -1.21V, and the corrosion current density was 7.54×10 -12 A / cm 2 After immersion in a 3.5% NaCl solution for 60 days, the impedance modulus of the coating was 1.31×10 -5Ω, phase angle -1.05, corrosion voltage -1.51 V, and corrosion current density 1.32 x 10 -9 A / cm 2 ; the impedance modulus and the corrosion current density remained at a high value, which represented good long-term corrosion resistance. After the SHEP + KH560-CeO2+FPOSS self-healing coating was immersed in 3.5% NaCl solution for 60 days, the coating impedance modulus was 9.14 x 10 -4 Ω, phase angle -1.69, corrosion voltage -1.53 V, and corrosion current density 5.12 x 10 -9 A / cm 2 ; the impedance modulus and the corrosion current density remained at a high value, which represented good long-term self-healing corrosion resistance.

[0075] Example 3

[0076] A method for preparing a self-healing super-hydrophobic corrosion-resistant composite coating, comprising the following steps:

[0077] S1, cleaning the magnesium alloy substrate to remove surface grease, floating dust and other contaminants, and then drying to obtain a pretreated substrate.

[0078] S2, preparation of a self-healing epoxy coating:

[0079] 1.5 g of KH560 was added to a mixed solution prepared from 35 g of n-butanol and 15 g of deionized water, and magnetically stirred for 30 min to obtain a suspension with a KH560 concentration of 30 g / L. Then, 2 g of CeO2 was added to the suspension, and magnetically stirred for another 50 min. After that, the mixture was dried at 100°C for 4 h to obtain KH560-modified CeO2.

[0080] 5 g of microcrystalline wax at 50 g / L was heated to melt at 90°C, and 0.5 g of sodium dodecylbenzenesulfonate at 5 g / L was added and magnetically stirred for 15 min to form a microcrystalline wax emulsion. Meanwhile, equal molar amounts of 22.8 g of BADGE, 14.8 g of NGDE, and 12.75 g of D230 were mixed with the microcrystalline wax emulsion by magnetic stirring to obtain a clear solution, which was denoted as SHEP. Then, 1.5 g of KH560-modified CeO2 at 80 g / L was added to the clear solution, and magnetically stirred for 60 min to obtain a self-healing epoxy coating, which was denoted as SHEP+KH560-CeO2, and was ready for use.

[0081] S3, preparation of a super-hydrophobic coating:

[0082] 5 g, 50 g / L of perfluorodecanethiol was added to a dichloromethane solution of 1.5 g, 15 g / L of OVPOSS and 0.15 g, 1.5 g / L of DMPA, and after irradiation under a UV lamp for 20 min, the fluorinated vinyl cage silsesquioxane nanoparticles, i.e. FPOSS nanoparticles, were obtained by washing with dichloromethane and drying; the FPOSS nanoparticles were added to an ethanol solution, ultrasonicated for 30 min to obtain a superhydrophobic coating, denoted as FPOSS, for standby use.

[0083] S4, Preparation of a self-healing superhydrophobic corrosion-resistant composite coating:

[0084] A self-healing epoxy coating was applied to a pretreated substrate and cured at 30°C for 40 h to form a self-healing epoxy coating, i.e. a primer coating, with a thickness of 500 μm; then, 5 g / L of FPOSS was coated on the substrate under light irradiation conditions at room temperature to dry to obtain a self-healing superhydrophobic corrosion-resistant composite coating, denoted as SHEP+KH560-CeO2+FPOSS.

[0085] The contact angle of a 3.5% NaCl water droplet on the surface of the prepared SHEP+KH560-CeO2+FPOSS was 167°, indicating that the prepared fabric surface had superhydrophobicity. The initial impedance modulus of the coating was 1.21×10 -10 Ω, the phase angle was -15.39, the corrosion voltage was -1.31 V, and the corrosion current density was 2.54×10 -12 A / cm 2 ; after immersion in a 3.5% NaCl solution for 60 days, the impedance modulus of the coating was 2.31×10 -5 Ω, the phase angle was -3.05, the corrosion voltage was -1.53 V, and the corrosion current density was 1.82×10 -9 A / cm 2 ; the impedance modulus and the corrosion current density remained at a relatively high value, demonstrating good long-term corrosion resistance. After self-healing, the SHEP+KH560-CeO2+FPOSS was immersed in a 3.5% NaCl solution for 60 days, the impedance modulus of the coating was 3.14×10 -4 Ω, the phase angle was -5.24, the corrosion voltage was -1.50 V, and the corrosion current density was 3.21×10 -9 A / cm 2 ; the impedance modulus and the corrosion current density remained at a relatively high value, demonstrating good long-term self-healing corrosion resistance.

[0086] Example 4

[0087] A method for preparing a self-healing superhydrophobic corrosion-resistant composite coating, comprising the following steps:

[0088] S1, cleaning the magnesium alloy substrate to remove surface grease, floating dust and other contaminants, drying to obtain a pretreated substrate.

[0089] S2, preparation of self-healing epoxy coating:

[0090] 2.5g of KH560 was added to the mixed solution prepared from 42g of n-butanol and 8g of deionized water, and magnetically stirred for 50min to obtain a suspension with a KH560 concentration of 50g / L. Then 3.5g of CeO2 was added to the suspension, and magnetically stirred for another 50min. Finally, the mixture was dried at 120℃ for 2h to obtain KH560 modified CeO2.

[0091] 7g of microcrystalline wax with a concentration of 70g / L was heated to melt at 95℃, and 0.7g of sodium dodecylbenzenesulfonate with a concentration of 7g / L was added. The mixture was magnetically stirred for 20min to form a microcrystalline wax emulsion. Meanwhile, equal molar amounts of 31.92g of BADGE, 20.72g of NGDE, 17.85g of D230 and the microcrystalline wax emulsion were mixed by magnetic stirring to obtain a clear solution, which was labeled as SHEP. 2g of KH560 modified CeO2 with a concentration of 70g / L was added to the clear solution, and magnetically stirred for 100min to obtain a self-healing epoxy coating, which was labeled as SHEP+KH560-CeO2 and stored for later use.

[0092] S3, preparation of superhydrophobic coating:

[0093] 10g of perfluorodecanethiol with a concentration of 100g / L was added to a dichloromethane solution containing 3g of OVPOSS with a concentration of 30g / L and 0.3g of DMPA with a concentration of 3g / L. The mixture was irradiated under a UV lamp for 25min, and then washed with dichloromethane and dried to obtain fluorinated vinyl cage silsesquioxane nanoparticles, i.e. FPOSS nanoparticles. The FPOSS nanoparticles were added to an ethanol solution and ultrasonicated for 40min to obtain a superhydrophobic coating, which was labeled as FPOSS and stored for later use.

[0094] S4, preparation of self-healing superhydrophobic corrosion-resistant composite coating:

[0095] The self-healing epoxy coating was applied to the pretreated substrate and cured at 40℃ for 30h to form a self-healing epoxy coating, i.e. a bottom layer coating, with a thickness of 1000μm. Then, FPOSS with a concentration of 60g / L was applied to the substrate, and the mixture was dried under light at room temperature to obtain a self-healing superhydrophobic corrosion-resistant composite coating, which was labeled as SHEP+KH560-CeO2+FPOSS.

[0096] The contact angle of a 3.5% NaCl water droplet on the surface of the prepared SHEP+KH560-CeO2+FPOSS was 169°, indicating that the prepared fabric surface had superhydrophobicity. The initial impedance modulus of the coating was 6.51×10 -10Ω, phase angle -11.24, corrosion voltage -1.22V, corrosion current density 4.24x10 -12 Ω / cm 2 ; after 60 days of immersion in 3.5% NaCl solution, the coating impedance modulus was 1.74x10 -5 Ω, phase angle -2.54, corrosion voltage -1.55V, corrosion current density 1.14x10 -9 Ω / cm 2 ; the impedance modulus and corrosion current density remained at a high value, demonstrating good long-term corrosion resistance. After 60 days of immersion in 3.5% NaCl solution, the coating impedance modulus was 8.54x10 -4 Ω, phase angle -4.85, corrosion voltage -1.54V, corrosion current density 1.52x10 -9 Ω / cm 2 ; the impedance modulus and corrosion current density remained at a high value, demonstrating good long-term self-healing corrosion resistance.

[0097] Example 5

[0098] A method for preparing a self-healing super-hydrophobic corrosion-resistant composite coating, comprising the following steps:

[0099] S1, cleaning the magnesium alloy substrate to remove surface grease, dust and other contaminants, and then drying to obtain a pretreated substrate.

[0100] S2, preparation of a self-healing epoxy coating:

[0101] 5g of KH560 was added to a mixed solution prepared from 47g of n-butanol and 3g of deionized water, and magnetically stirred for 60min to obtain a suspension with a KH560 concentration of 100g / L. Then 7g of CeO2 was added to the suspension, and magnetically stirred for another 60min. The mixture was then dried at 150℃ for 1h to obtain KH560-modified CeO2.

[0102] 10g of microcrystalline wax at 100℃ was heated and melted, and 1g of 10g / L sodium dodecylbenzenesulfonate was added and magnetically stirred for 30min to form a microcrystalline wax emulsion. Meanwhile, equal molar amounts of 45.6g of BADGE, 29.6g of NGDE, 25.5g of D230 and the microcrystalline wax emulsion were mixed by magnetic stirring to obtain a clear solution, which was labeled as SHEP. 3g of 100g / L KH560-modified CeO2 was added to the clear solution, and magnetically stirred for 120min to obtain a self-healing epoxy coating, which was labeled as SHEP+KH560-CeO2 and stored for later use.

[0103] S3, preparation of a super-hydrophobic coating:

[0104] 15 g of 150 g / L perfluorodecyl mercaptan was added to a dichloromethane solution containing 5 g of 50 g / L OVPOSS and 0.5 g of 5 g / L DMPA. After irradiation under a UV lamp for 30 min, the solution was washed with dichloromethane and dried to obtain fluorinated vinyl cage-type silsesquioxane nanoparticles, i.e., FPOSS nanoparticles. The FPOSS nanoparticles were added to an ethanol solution and sonicated for 60 min to obtain a superhydrophobic coating, denoted as FPOSS, for later use.

[0105] S4. Preparation of self-healing superhydrophobic and corrosion-resistant composite coating:

[0106] A self-healing epoxy coating was applied to the pretreated substrate and cured at 60°C for 2 hours to form a self-healing epoxy coating, i.e., the base coat, with a thickness of 2000 μm. Then, FPOSS containing 100 g / L was applied to the substrate and dried at room temperature under light conditions to obtain a self-healing superhydrophobic and corrosion-resistant composite coating, i.e., the top coat, denoted as SHEP+KH560-CeO2+FPOSS.

[0107] The contact angle of 3.5% NaCl water droplets on the prepared SHEP+KH560-CeO2+FPOSS surface was 169°, indicating that the prepared fabric surface has superhydrophobicity. The initial impedance modulus of the coating was 9.51 × 10⁻⁶. -10 Ω, phase angle -15.32, corrosion voltage -1.20V, corrosion current density 9.52×10 -12 A / cm 2 After being soaked in a 3.5% NaCl solution for 60 days, the coating's impedance modulus was 2.14 × 10⁻⁶. -5 Ω, phase angle -4.21, corrosion voltage -1.56V, corrosion current density 2.51×10 -9 A / cm 2 The impedance modulus and corrosion current density remained at high values, demonstrating good long-term corrosion resistance. After immersion in 3.5% NaCl solution for 60 days following self-healing, the SHEP+KH560-CeO2+FPOSS coating exhibited an impedance modulus of 9.24 × 10⁻⁶. -4 Ω, phase angle -3.54, corrosion voltage -1.51V, corrosion current density 3.24×10 -9 A / cm 2 The impedance modulus and corrosion current density remain at high values, demonstrating good long-term self-healing corrosion protection performance.

[0108] Depend on Figure 1 Figure a shows that the SHEP coating has a dense surface; Figure 1b of FIG. 1 shows that there are many nanoparticles on the surface of the coating, which indicates that the KH560-CeO2 successfully doped the SHEP coating; from c of FIG. 1, it can be seen that the FPOSS coating is very rough and has many nanopores; from d of FIG. 1, it can be seen that the surface microstructure of SHEP+KH560-CeO2+FPOSS is similar to that of the FPOSS coating. The combination of the SHEP+KH560-CeO2 coating and the FPOSS coating endows the SHEP+KH560-CeO2+FPOSS double layer with the advantages of the compact SHEP+KH560-CeO2 bottom layer and the rough FPOSS top layer. Figure 1 Figure 1 b of FIG. 1 shows that there are many nanoparticles on the surface of the coating, which indicates that the KH560-CeO2 successfully doped the SHEP coating; from c of FIG. 1, it can be seen that the FPOSS coating is very rough and has many nanopores; from d of FIG. 1, it can be seen that the surface microstructure of SHEP+KH560-CeO2+FPOSS is similar to that of the FPOSS coating. The combination of the SHEP+KH560-CeO2 coating and the FPOSS coating endows the SHEP+KH560-CeO2+FPOSS double layer with the advantages of the compact SHEP+KH560-CeO2 bottom layer and the rough FPOSS top layer.

[0109] b of FIG. 1 shows that there are many nanoparticles on the surface of the coating, which indicates that the KH560-CeO2 successfully doped the SHEP coating; from c of FIG. 1, it can be seen that the FPOSS coating is very rough and has many nanopores; from d of FIG. 1, it can be seen that the surface microstructure of SHEP+KH560-CeO2+FPOSS is similar to that of the FPOSS coating. The combination of the SHEP+KH560-CeO2 coating and the FPOSS coating endows the SHEP+KH560-CeO2+FPOSS double layer with the advantages of the compact SHEP+KH560-CeO2 bottom layer and the rough FPOSS top layer. Figure 2 b of FIG. 1 shows that there are many nanoparticles on the surface of the coating, which indicates that the KH560-CeO2 successfully doped the SHEP coating; from c of FIG. 1, it can be seen that the FPOSS coating is very rough and has many nanopores; from d of FIG. 1, it can be seen that the surface microstructure of SHEP+KH560-CeO2+FPOSS is similar to that of the FPOSS coating. The combination of the SHEP+KH560-CeO2 coating and the FPOSS coating endows the SHEP+KH560-CeO2+FPOSS double layer with the advantages of the compact SHEP+KH560-CeO2 bottom layer and the rough FPOSS top layer.

[0110] b of FIG. 1 shows that there are many nanoparticles on the surface of the coating, which indicates that the KH560-CeO2 successfully doped the SHEP coating; from c of FIG. 1, it can be seen that the FPOSS coating is very rough and has many nanopores; from d of FIG. 1, it can be seen that the surface microstructure of SHEP+KH560-CeO2+FPOSS is similar to that of the FPOSS coating. The combination of the SHEP+KH560-CeO2 coating and the FPOSS coating endows the SHEP+KH560-CeO2+FPOSS double layer with the advantages of the compact SHEP+KH560-CeO2 bottom layer and the rough FPOSS top layer. Figure 3 b of FIG. 1 shows that there are many nanoparticles on the surface of the coating, which indicates that the KH560-CeO2 successfully doped the SHEP coating; from c of FIG. 1, it can be seen that the FPOSS coating is very rough and has many nanopores; from d of FIG. 1, it can be seen that the surface microstructure of SHEP+KH560-CeO2+FPOSS is similar to that of the FPOSS coating. The combination of the SHEP+KH560-CeO2 coating and the FPOSS coating endows the SHEP+KH560-CeO2+FPOSS double layer with the advantages of the compact SHEP+KH560-CeO2 bottom layer and the rough FPOSS top layer. Figure 3 b of FIG. 1 shows that there are many nanoparticles on the surface of the coating, which indicates that the KH560-CeO2 successfully doped the SHEP coating; from c of FIG. 1, it can be seen that the FPOSS coating is very rough and has many nanopores; from d of FIG. 1, it can be seen that the surface microstructure of SHEP+KH560-CeO2+FPOSS is similar to that of the FPOSS coating. The combination of the SHEP+KH560-CeO2 coating and the FPOSS coating endows the SHEP+KH560-CeO2+FPOSS double layer with the advantages of the compact SHEP+KH560-CeO2 bottom layer and the rough FPOSS top layer.

[0111] b of FIG. 1 shows that there are many nanoparticles on the surface of the coating, which indicates that the KH560-CeO2 successfully doped the SHEP coating; from c of FIG. 1, it can be seen that the FPOSS coating is very rough and has many nanopores; from d of FIG. 1, it can be seen that the surface microstructure of SHEP+KH560-CeO2+FPOSS is similar to that of the FPOSS coating. The combination of the SHEP+KH560-CeO2 coating and the FPOSS coating endows the SHEP+KH560-CeO2+FPOSS double layer with the advantages of the compact SHEP+KH560-CeO2 bottom layer and the rough FPOSS top layer. Figure 4 b of FIG. 1 shows that there are many nanoparticles on the surface of the coating, which indicates that the KH560-CeO2 successfully doped the SHEP coating; from c of FIG. 1, it can be seen that the FPOSS coating is very rough and has many nanopores; from d of FIG. 1, it can be seen that the surface microstructure of SHEP+KH560-CeO2+FPOSS is similar to that of the FPOSS coating. The combination of the SHEP+KH560-CeO2 coating and the FPOSS coating endows the SHEP+KH560-CeO2+FPOSS double layer with the advantages of the compact SHEP+KH560-CeO2 bottom layer and the rough FPOSS top layer. -6 -9 2 -3 -6 2 ​​​​​​; after 60 days of immersion in 1 mol / L NaOH solution, the impedance modulus of SHEP+KH560-CeO2 was 9.41 x 10 -4 Ω, the corrosion voltage was -1.53 V, and the corrosion current density was 2.48 x 10 -7 A / cm 2 ; the impedance modulus and the corrosion current density remained at a high value, indicating that SHEP+KH560-CeO2 had good long-term corrosion resistance.

[0112] By Figure 5 , the initial impedance modulus of SHEP+KH560-CeO2+FPOSS was 2.41 x 10 -10 Ω, the phase angle was -10.39, the corrosion voltage was -1.14 V, and the corrosion current density was 8.61 x 10 -12 A / cm 2 ; after 60 days of immersion in 3.5% NaCl solution, the impedance modulus of SHEP+KH560-CeO2+FPOSS was 1.53 x 10 -5 Ω, the phase angle was -2.06, the corrosion voltage was -1.48 V, and the corrosion current density was 1.54 x 10 -9 A / cm 2 ; after 60 days of immersion in 1 mol / L NaOH solution, the impedance modulus of SHEP+KH560-CeO2+FPOSS was 1.75 x 10 -4 Ω, the phase angle was -3.85, the corrosion voltage was -1.6 V, and the corrosion current density was 1.49 x 10 -9 A / cm 2 ; the impedance modulus and the corrosion current density remained at a high value, indicating that SHEP+KH560-CeO2+FPOSS had good long-term corrosion resistance. Compared with the SHEP+KH560-CeO2 base coating, the initial corrosion resistance was improved by 4 orders of magnitude in initial impedance modulus, the initial corrosion voltage was positively shifted by 0.34 V, and the initial corrosion current density was improved by 3 orders of magnitude. After 60 days of immersion experiment, the long-term corrosion resistance of the base coating was significantly improved.

[0113] By Figure 6 , after 60 days of immersion in 3.5% NaCl solution, the impedance modulus of SHEP+KH560-CeO2+FPOSS was 9.41 x 10 -4 Ω, the phase angle was -3.69, the corrosion voltage was -1.52 V, and the corrosion current density was 5.33 x 10 -9 A / cm 2; After 60 days of immersion in 1 mol / L NaOH solution, the impedance modulus of SHEP+KH560-CeO2+FPOSS was 3.2 x 10 -4 Ω, the phase angle was -2.46, the corrosion voltage was -1.49 V, and the corrosion current density was 4.83 x 10 -8 A / cm 2 ; the impedance modulus and the corrosion current density still maintained at a high value, which embodied the good long-term self-healing corrosion protection performance of SHEP+KH560-CeO2+FPOSS.

[0114] Although preferred embodiments of the application have been described, those skilled in the art will be able to make additional changes and modifications, which embody the principles of the application, once they have the basic inventive concept. Therefore, the appended claims are intended to cover all such changes and modifications that fall within the scope of the application.

Claims

1. A method for preparing a self-healing superhydrophobic corrosion-resistant composite coating, characterized in that, Includes the following steps: A suspension of silane coupling agent KH560 was mixed with CeO2 to carry out a substitution reaction, resulting in KH560 modified CeO2. A self-healing epoxy coating is obtained by mixing shape memory polymer bisphenol A diglycidyl ether, diluent neopentyl glycol diglycidyl ether, crosslinking agent polyetheramine, microcrystalline wax emulsion, and KH560 modified CeO2. Bisphenol A diglycidyl ether and neopentyl glycol diglycidyl ether initiate an epoxy ring-opening reaction through the amino groups of polyetheramine, gradually forming a crosslinking network. The coating is then mixed evenly with microcrystalline wax emulsion and KH560 modified CeO2. Perfluorodecyl thiols, octavinyl cage silsesquioxane and photoinitiator 2,2-dimethoxy-2-phenylacetophenone were mixed and subjected to thiol-ene click reaction under the action of photoinitiator to obtain fluorinated vinyl cage silsesquioxane nanoparticles. Fluorinated vinyl cage-type silsesquioxane nanoparticles were mixed with an ethanol solution to obtain a superhydrophobic coating. After applying the self-healing epoxy coating, a curing process is performed to form a self-healing epoxy coating. A superhydrophobic coating is deposited on a self-healing epoxy coating. After drying, under the action of a photoinitiator, an addition reaction occurs between the epoxy body of the bottom self-healing epoxy coating and the vinyl body of the top superhydrophobic coating to obtain a self-healing superhydrophobic corrosion-resistant composite coating. The mass ratio of bisphenol A diglycidyl ether, neopentyl glycol diglycidyl ether, polyetheramine, microcrystalline wax emulsion to KH560 modified CeO2 is 1~10:1~10:1~10:10~100:10~100; The mass ratio of perfluorodecyl mercaptan, octavinylcage-type silsesquioxane, and 2,2-dimethoxy-2-phenylacetophenone is 3~150:1~50:0.1~5.

2. The method for preparing a self-healing superhydrophobic corrosion-resistant composite coating according to claim 1, characterized in that, The conditions for the thiol-alkene click reaction are: under ultraviolet light irradiation, the reaction is carried out at 10℃~30℃ for 0.5h~2h.

3. The method for preparing a self-healing superhydrophobic corrosion-resistant composite coating according to claim 1, characterized in that, The mass ratio of silane coupling agent KH560 to CeO2 is 1~5:2~10.

4. The method for preparing a self-healing superhydrophobic corrosion-resistant composite coating according to claim 1, characterized in that, Microcrystalline wax emulsions are prepared according to the following steps: Microcrystalline wax is melted and mixed with a dispersant to obtain a microcrystalline wax emulsion; wherein the mass ratio of microcrystalline wax to dispersant is 10~100:1~10.

5. The method for preparing a self-healing superhydrophobic corrosion-resistant composite coating according to claim 1, characterized in that, The addition reaction is carried out under light conditions and then dried at room temperature.

6. The method for preparing a self-healing superhydrophobic corrosion-resistant composite coating according to claim 1, characterized in that, The thickness of the self-healing epoxy coating ranges from 5 μm to 2000 μm.

7. A self-healing superhydrophobic and corrosion-resistant composite coating prepared by the preparation method according to any one of claims 1 to 6.

8. The application of the self-healing superhydrophobic corrosion-resistant composite coating of claim 7 in the preparation of fabric preservatives, anti-icing and anti-icing agents or self-cleaning agents.

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