Preparation method of super-hydrophobic composite coating capable of being stripped after being electrified

Abstract

The invention discloses a preparation method of a super-hydrophobic composite coating capable of being stripped after being electrified, which comprises the following steps: firstly, coating an ion coating on the surface of a protective base material, coating a super-hydrophobic electronic coating on the surface of the ion coating after the ion coating is cured and dried to a certain degree, and after the ion coating and the super-hydrophobic electronic coating are completely cured and dried, preparing the super-hydrophobic composite coating capable of being stripped after being electrified. The super-hydrophobic composite coating capable of being stripped after being electrified is obtained. The ion coating is an ionic polymer system with ion transmission capacity, a copolymerization type ionic polymer system formed by copolymerizing an ionic monomer and a functional monomer, or a blending type ionic polymer system formed by compounding a first matrix polymer, a functional polymer and an ionic filler. The super-hydrophobic composite coating prepared by the invention has excellent waterproof, protective and anti-pollution properties, and can be quickly stripped under an electrified condition. The method can solve the problem of high energy consumption of a traditional mechanical method for removing the failed coating, and effectively reduces physical damage to the protective base material.

Description

Technical Field

[0001] The present invention belongs to the technical field of functional material preparation, and more specifically, the present invention relates to a preparation method of a superhydrophobic composite coating that can be peeled off by electrification. Background Art

[0002] A superhydrophobic coating is a protective material with a surface contact angle greater than 150° and a rolling angle less than 10°, and has protective properties such as waterproof, antifouling, dustproof, anticorrosion, antifrost, and anti-icing. Regarding superhydrophobic protective coatings, the main focus of current researchers is on how to improve the adhesion and protective ability of the coatings, and rarely pay attention to the problem of how to quickly and effectively remove the failed coatings after the coatings reach their service life. Although the mechanical removal methods such as sandblasting and laser ablation can be used to achieve the peeling of the failed coatings, there are problems such as high energy consumption, low peeling efficiency, and large damage to the substrate, which are very unfavorable for practical applications. Therefore, it is of great practical significance to develop a superhydrophobic coating that can be peeled off quickly and efficiently. Summary of the Invention

[0003] An object of the present invention is to solve at least the above problems and / or defects, and provide at least the advantages described hereinafter.

[0004] To achieve these objects and other advantages in accordance with the present invention, there is provided a preparation method of a superhydrophobic composite coating that can be peeled off by electrification, including: first, an ionic coating is coated on the surface of a protective substrate, and after the ionic coating is cured and dried to a certain extent, a superhydrophobic electronic coating is coated on the surface of the ionic coating. After the ionic coating and the superhydrophobic electronic coating are completely cured and dried, a superhydrophobic composite coating that can be peeled off by electrification is obtained; The preparation method of the superhydrophobic composite coating that can be peeled off by electrification specifically includes: S1. Mix a second matrix polymer (0 wt% - 50 wt%), an electronic filler (0 wt% - 50 wt%), a non-conductive nano filler (0 wt% - 20 wt%) with a solvent 2 (5 - 100 times the mass of the superhydrophobic electronic coating), ultrasonically disperse, and add a hydrophobic modifier (0 - 30 wt% of the electronic filler material) to hydrophobically modify the electronic filler to obtain a superhydrophobic electronic coating; A curing agent and a catalyst can be optionally used. The curing agent includes a 593 curing agent, and the catalyst includes dibutyltin dilaurate; S2. Mix the first matrix polymer, functional polymer (5 wt% - 50 wt%), solvent 1 (5 - 100 times the mass of the ionic coating), and ionic filler (5 wt% - 50 wt%) to obtain an ionic coating. Curing agents (593 curing agent, ethylenediamine) and catalysts (dibutyltin dilaurate) can be optionally used; or copolymerize ionic monomers (10 wt% - 100 wt%) and functional monomers (0 wt% - 90 wt%) to obtain an ionic coating; or crosslink polyether polyol, inorganic metal salt, and isocyanates (including polyisocyanates, hexamethylene diisocyanate, dicyclohexylmethane diisocyanate, isophorone diisocyanate) under the catalysis of a catalyst to obtain an ionic coating. S3. Coating the prepared ionic coating on the surface of the protective substrate, after standing for curing, evenly coat the superhydrophobic electronic coating on the surface of the ionic coating. After the ionic coating and the superhydrophobic electronic coating are completely cured and dried, a superhydrophobic composite coating that can be electrically peeled off is obtained.

[0005] Preferably, the ionic coating is an ionic polymer system with ionic transport ability, a copolymeric ionic polymer system formed by copolymerizing ionic monomers and functional monomers, or a blended ionic polymer system formed by compounding a first matrix polymer, a functional polymer, and an ionic filler. The ionic monomers in the copolymeric ionic polymer system refer to olefin monomers that can dissociate into anions and cations and contain carbon-carbon double bonds that can undergo free radical polymerization. The carbon-carbon double bonds of the olefin monomers can be bonded to anions or cations, that is, the free ions are cations or anions. The ionic monomers in the copolymeric ionic polymer system are ionic soft monomers with a glass transition temperature of the homopolymer less than 0 °C or ionic hard monomers with a glass transition temperature of the homopolymer greater than 0 °C. The functional monomers in the copolymeric ionic polymer system refer to olefin monomers or glycerol ether monomers used to adjust the hardness, modulus, adhesion, glass transition temperature of the copolymeric ionic polymer system, or introduce physical and chemical crosslinking sites in the ionic polymer system; the olefin monomers include water-soluble olefin monomers or oil-soluble olefin monomers, specifically including: styrene, acrylic acid, methacrylic acid, acrylonitrile, acrylate esters, methacrylate esters, vinyl acetate, acrylamide, vinyl pyrrolidone, 2-acrylamido-2-methylpropanesulfonic acid, styrenesulfonic acid, sodium styrenesulfonate, isooctyl acrylate, isocyanates, etc., and the glycerol ether monomers include one or more of polyethylene glycol diglycidyl ether and polypropylene oxide diglycidyl ether. The polymerization methods of the copolymeric ionic polymer system include one or more of bulk polymerization, solution polymerization, emulsion polymerization, suspension polymerization, inverse emulsion polymerization, seed emulsion polymerization, and inverse suspension polymerization. When the copolymeric ionic polymer system is polymerized, the content of the ionic monomer accounts for 10 wt% - 100 wt% of the copolymeric ionic polymer system, and the content of the functional monomer accounts for 0 wt% - 90 wt% of the copolymeric ionic polymer system.

[0006] Preferably, the first matrix polymer of the blended ionic polymer system refers to a common polymer resin or a copolymeric ionic polymer system with strong adhesion. The polymer resin includes one or more of polyurethane, epoxy resin, phenolic resin, polyester resin, acrylic resin, silicone resin, polyamide, polyimide, polyvinyl alcohol, polyvinyl chloride resin, bisphenol A epoxy resin, and fluorophosphate resin.

[0007] Preferably, the functional polymer of the blended ionic polymer system refers to a polymer material or a copolymeric ionic polymer system with ionic complexation sites that can improve the ionic transport performance of the blended ionic polymer system. The polymer material includes one or more of polylactic acid, polyethylene oxide, polypropylene oxide, polyacrylonitrile, polytetrafluoroethylene, polyvinylidene fluoride, polyacrylate, polydimethylsiloxane, polycaprolactone, polyethyl carbonate, polypropyl carbonate, trimethyl carbonate, and polyether polyol. The dosage of the functional polymer accounts for 5 wt% - 50 wt% of the blended ionic polymer system.

[0008] Preferably, the ionic filler of the blended ionic polymer system refers to an organic salt or an inorganic salt that can dissociate into free anions and free cations, including ionic liquids, organometallic salts, inorganic metal salts, and deep eutectic solvents. The ionic filler is a single ionic filler or a combination of multiple ionic fillers. The dosage of the ionic filler accounts for 5 wt% - 50 wt% of the blended ionic polymer system.

[0009] Preferably, in order to improve the miscibility, fluidity, and workability of the ionic coating, a solvent 1 is introduced into the copolymeric ionic polymer system and the blended ionic polymer system in the ionic coating. The solvent 1 includes one or more of water, benzene, toluene, methanol, ethanol, propanol, acetone, acetonitrile, acetic acid, hexane, heptane, chloroform, n-butanol, isopentane, n-pentane, cyclopentane, petroleum ether, cyclohexane, ethyl acetate, butyl acetate, trifluoroacetic acid, ethyl acetate, and butyl acetate. The cross-linking method inside the copolymeric ionic polymer system and the blended ionic polymer system is a thermosetting type with chemical cross-linking or a thermoplastic type with only physical cross-linking without chemical cross-linking. The coating processing method of the ionic coating on the surface of the protective substrate is any one or more of brushing, scraping, spraying, or dipping. The protective substrate refers to a metal substrate or an electronically conductive substrate, including: copper, iron, magnesium, zinc, nickel, beryllium, tungsten, stainless steel, metal alloy, or a polymer conductive composite; if the surface of the protective substrate is not electronically conductive, conductive treatment is required; The curing and drying methods of the ion coating include standing at room temperature, air drying, heating, radiation, and ultraviolet irradiation; the ion coating is cured and dried to a certain extent means that the bulk viscosity of the ion coating reaches 5000 mPa·s or more; The ion transport ability of the ion coating refers to that the ionic conductivity of the ion coating after being completely cured and dried is greater than 1×10 -6 S / cm.

[0010] Preferably, the superhydrophobic electronic coating is obtained by compounding a second matrix polymer and an electronic filler. In order to improve the dispersibility of the electronic filler and the fluidity and workability of the superhydrophobic electronic coating, a solvent 2 is introduced during the compounding of the second matrix polymer and the electronic filler. The solvent 2 includes: water, benzene, toluene, methanol, ethanol, propanol, acetone, acetonitrile, acetic acid, hexane, heptane, chloroform, n-butanol, isopentane, n-pentane, cyclopentane, petroleum ether, cyclohexane, ethyl acetate, butyl acetate, trifluoroacetic acid, ethyl acetate, butyl acetate, or one or more of them; The second matrix polymer of the superhydrophobic electronic coating refers to a high molecular resin material with strong adhesion, including: polyurethane, epoxy resin, phenolic resin, polyester resin, acrylic resin, silicone resin, polyamide, polyimide, polyvinyl alcohol, polyvinyl chloride, bisphenol A epoxy resin, methyl silicone resin, or one or more of them; the dosage of the second matrix polymer accounts for 0 wt% - 50 wt% of the superhydrophobic electronic coating; The electronic filler of the superhydrophobic electronic coating refers to a micro-nano material or a polymer material with electronic conduction ability, including: acetic acid, ammonia water, conductive graphite, conductive carbon black, reduced graphene oxide, graphene, carbon nanotubes, metal nanowires, metal micro-nano powders, metal alloy micro-nano powders, conductive metal oxides, conductive polymers, liquid metals, or one or more of them; the metal micro-nano powders include one or more of gold powder, silver powder, magnesium powder, aluminum powder, zinc powder; the metal alloy micro-nano powders include one or more of magnesium-aluminum alloy powder, zinc-magnesium alloy powder, magnesium-aluminum-zinc alloy powder, zinc-aluminum alloy powder, copper-silver alloy powder, nickel-copper alloy powder; the conductive metal oxides include one or more of antimony-doped tin dioxide, aluminum-doped zinc oxide, indium-doped tin oxide; the conductive polymers include one or more of doped polyaniline, doped polypyrrole, doped polythiophene; the liquid metals include one or more of indium-tin alloy, gallium-tin alloy, gallium-indium-tin alloy; the dosage of the electronic filler accounts for 0 wt% - 50 wt% of the superhydrophobic electronic coating.

[0011] Preferably, the electronic filler of the superhydrophobic electronic coating is hydrophobically modified with a hydrophobic modifier, and the hydrophobic modifier includes one or more of: 1H,1H,2H,2H-perfluorodecyltriethoxysilane, heptadecafluorodecyltrimethoxysilane, 3-aminopropyltrimethoxysilane, cetyltrimethoxysilane, fluorosilane, trifluorochlorosilane, polytetrafluoroethylene, n-octyltrifluorochlorosilane, cycloalkylsilane, hexamethyldisiloxane, polymethylhydrosiloxane, tetrabutyl titanate; hydrophobically modifying the electronic filler is to reduce the surface energy of the superhydrophobic electronic coating and improve the superhydrophobic properties of the superhydrophobic electronic coating; To increase the roughness of the superhydrophobic electronic coating and improve the hydrophobicity, non-conductive nano-fillers are introduced into the superhydrophobic electronic coating, and the non-conductive nano-fillers include one or more of: silica nanoparticles, alumina nanoparticles, zinc oxide nanoparticles, titanium oxide nanoparticles, polystyrene microspheres; the amount of the non-conductive nano-fillers accounts for 0 wt% - 20 wt% of the superhydrophobic electronic coating.

[0012] Preferably, the coating method of the superhydrophobic electronic coating on the surface of the ion coating is one or more of brushing, scraping, spraying or dipping; The curing and drying method of the superhydrophobic electronic coating includes one of standing at room temperature, air drying, heating, radiation, ultraviolet irradiation; The electronic transport ability of the superhydrophobic electronic coating means that the electronic conductivity of the superhydrophobic electronic coating after complete curing and drying is less than 0.01 S / m.

[0013] Preferably, the energization of the electrically peelable means applying a voltage on both sides of the protective substrate and the superhydrophobic electronic coating, the applied voltage is direct current or alternating current, the magnitude of the applied voltage is 6 - 150V, and the energization time is 0 - 120 min; The peeling of the electrically peelable means that the adhesion reduction ratio of the ion coating before and after energization is greater than 50%, so as to facilitate the rapid peeling of the ion coating and the superhydrophobic electronic coating from the substrate.

[0014] The present invention has at least the following beneficial effects: The superhydrophobic composite coating prepared by the present invention has excellent waterproof, protective and anti-pollution properties, and can achieve rapid peeling of the coating under energized conditions. The present invention can solve the high energy consumption problem of removing the failed coating by the traditional mechanical method and effectively reduce the physical damage to the protective substrate.

[0015] Other advantages, objectives and features of the present invention will be partially reflected by the following description and partially understood by those skilled in the art through the research and practice of the present invention. Description of the Drawings

[0016] Figure 1Thrust test curve of the superhydrophobic composite coating prepared in Example 1; Figure 2 Thrust test curve of the superhydrophobic composite coating prepared in Example 4; Figure 3 Schematic diagram of electro-induced peeling of the superhydrophobic composite coating. Detailed implementation manners

[0017] The present invention will be further described in detail below with reference to the accompanying drawings, so that those skilled in the art can implement it according to the description in the specification.

[0018] It should be understood that the terms such as "having", "comprising" and "including" used herein do not exclude the presence or addition of one or more other elements or their combinations.

[0019] Example 1 A preparation method of an electro-conductive peelable superhydrophobic composite coating specifically includes the following steps: S1: By weight, 10 parts of ammonia water, 20 parts of deionized water, 200 parts of absolute ethanol and 10 parts of carbon nanotubes (diameter 10 - 15 nm, length 9 - 15 μm) are ultrasonically dispersed for 10 min, and then 1 part of 1H,1H,2H,2H-perfluorodecyltriethoxysilane is added and stirred for 24 h to obtain a superhydrophobic electronic coating.

[0020] S2: By weight, 30 parts of polyethylene oxide with a number average molecular weight of 600 g·mol -1 , 100 parts of bisphenol A epoxy resin E51 (industrial grade), 30 parts of 593 curing agent (industrial grade) and 27 parts of 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (ionic liquid) are fully stirred and mixed evenly to obtain an ionic coating.

[0021] S3: Using a stainless steel plate as the protective substrate, the ionic coating prepared in S2 is brush-coated on its surface and left standing at room temperature for 1 h; then the superhydrophobic electronic coating prepared in S1 is evenly sprayed on the surface of the ionic coating and left standing at room temperature for another 24 h to obtain an electro-conductive peelable superhydrophobic composite coating.

[0022] For the superhydrophobic composite coating prepared according to Example 1, the surface contact angle reaches 160º and the rolling angle reaches 5º, and when a DC voltage is applied (as shown in the schematic diagram of electro-induced peeling of the superhydrophobic composite coating) Figure 3 ), the peeling behavior of the composite coating can be clearly observed. As Figure 1 and Table 1 show, without applying voltage, the adhesion of the composite coating can reach 2.92 N / mm 2When a DC voltage of 60 V is applied across the protective substrate and the superhydrophobic electronic coating for 2 min, the adhesion of the composite coating is reduced to 0.4 N / mm 2 (The coating thrust test curve is as shown in Figure 1 ). Moreover, the effect of the electrified peeling of the composite coating becomes more and more obvious with the increase of voltage and the extension of the electrified time. After applying a DC voltage of 90 V for 5 min, the adhesion of the composite coating decays to 0.208 N / mm 2 (as shown in Table 1).

[0023] Table 1 Example 2: A preparation method of an electrified peelable superhydrophobic composite coating specifically includes the following steps: S1: By weight, add 10 parts of reduced graphene oxide, 20 parts of deionized water and 2 parts of acetic acid into 150 parts of acetone. After ultrasonic dispersion for 30 min, under stirring, add 2 parts of heptadecafluorodecyltrimethoxysilane, continuously stir for 24 h, then add 10 parts of bisphenol A epoxy resin E51, continuously stir for 15 min, and then add 3 parts of 593 curing agent, continuously stir for 15 min to obtain a superhydrophobic electronic coating.

[0024] S2: By weight, fully stir 50 parts of polyether polyol with a number average molecular weight of 2000 g·mol -1 , 30 parts of lithium bis(trifluoromethanesulfonyl)imide (inorganic metal salt) and 100 parts of acetone to mix evenly; then add 20 parts of polyisocyanate and 1 part of dibutyltin dilaurate and mix evenly to obtain an ionic coating.

[0025] S3: Using a copper plate as the protective substrate, spray the ionic coating prepared in S2 on its surface and let it stand at room temperature for 30 min; then evenly spray the superhydrophobic electronic coating prepared in S1 on the surface of the ionic coating, and continue to let it stand at room temperature for 24 h to obtain an electrified peelable superhydrophobic composite coating.

[0026] For the superhydrophobic composite coating prepared according to Example 2, the surface contact angle reaches 158° and the rolling angle reaches 7°. Moreover, when a DC voltage is connected, the peeling behavior of the composite coating can be clearly observed. As shown in Table 2, without electrification, the adhesion of the composite coating can reach 3.62 N / mm 2 When a DC voltage of 30 V is applied across the protective substrate and the superhydrophobic electronic coating for 3 min, the adhesion of the composite coating is reduced to 0.5 N / mm 2Moreover, the effect of the electro-stripping of the composite coating becomes more and more obvious with the increase of voltage and the extension of the electro-stripping time. When a DC voltage of 150 V is applied continuously for 15 min, the adhesion of the composite coating decays to 0.12 N / mm 2 .

[0027] Table 2 Example 3: A preparation method of an electro-strippable superhydrophobic composite coating specifically includes the following steps: S1: By weight, add 8 parts of silver nanowires, 2 parts of silicon dioxide nanoparticles and 0.1 part of acetic acid into 100 parts of ethyl acetate. After ultrasonic dispersion for 30 min, under stirring, add 0.5 part of heptadecafluorodecyltrimethoxysilane and stir for 12 h; under stirring, add 8 parts of polyacrylate resin with a number average of 100,000 g·mol -1 to obtain a superhydrophobic electronic coating after stirring for 1 h.

[0028] S2: By weight, fully dissolve 75 parts of isooctyl acrylate, 25 parts of 1-vinyl-3-butylimidazolium bis(trifluoromethylsulfonyl)imide, 10 parts of acrylic acid and 3 parts of benzoyl peroxide in 300 parts of ethyl acetate. Under the protection of dry inert gas, gradually heat up to 70 °C and react for 24 h, discharge and add 20 parts of lithium bis(trifluoromethylsulfonyl)imide and 1 part of isophorone diisocyanate, and mix evenly to obtain an ionic coating.

[0029] S3: Using stainless steel as the protective substrate, spray the ionic coating prepared in S2 on its surface and let it stand at room temperature for curing for 30 min; then evenly spray the superhydrophobic electronic coating prepared in S1 on the surface of the ionic coating, and continue to let it stand at room temperature for 72 h to obtain an electro-strippable superhydrophobic composite coating.

[0030] For the superhydrophobic composite coating prepared according to Example 3, the surface contact angle reaches 155° and the rolling angle reaches 7°. Moreover, under the condition of connecting a DC voltage, the stripping behavior of the composite coating can be clearly observed. As shown in Table 3, without applying voltage, the adhesion of the composite coating can reach 3.4 N / mm 2 . When a DC voltage of 50 V is applied between the protective substrate and the superhydrophobic electronic coating and continuously applied for 1 min, the adhesion of the composite coating decreases to 0.61 N / mm 2 . Moreover, the effect of the electro-stripping of the composite coating becomes more and more obvious with the increase of voltage and the extension of the electro-stripping time. When a DC voltage of 150 V is applied continuously for 5 min, the adhesion of the composite coating decays to 0.12 N / mm 2 .

[0031] Table 3 Example 4: A preparation method of an electro - strippable super - hydrophobic composite coating, specifically including the following steps: S1: By weight, add 15 parts of graphene and 3 parts of 1H,1H,2H,2H - perfluorooctyltriethoxysilane into 100 parts of acetone, and ultrasonicate for 1 h; under stirring, add 10 parts of fluorophosphorus resin, after stirring for 30 min, add 1 part of hexamethylene diisocyanate, and after stirring for 30 min, obtain a super - hydrophobic electronic coating.

[0032] S2: By weight, add 40 parts of 1 - styryl - 3 - ethylimidazolium bis(trifluoromethylsulfonyl)imide, 60 parts of 1 - acryloyloxyethyl - 3 - butylimidazolium bis(trifluoromethylsulfonyl)imide, 20 parts of 1 - ethyl - 3 - methylimidazolium acryloyloxypropylsulfonate, 20 parts of acrylamide and 5 parts of benzoyl peroxide into 200 parts of acetonitrile in turn and dissolve them fully; under the protection of dry inert gas, gradually heat up to 75 °C and react for 24 h. After discharging, add 10 parts of lithium hexafluorophosphate and 1.5 parts of dicyclohexylmethane diisocyanate, and mix evenly to obtain an ionic coating.

[0033] S3: Using an iron plate as the protective substrate, brush - coat the ionic coating prepared in S2 on its surface and let it stand at room temperature for 1 h; then evenly brush - coat the super - hydrophobic electronic coating prepared in S1 on the surface of the ionic coating, and continue to let it stand at room temperature for 36 h to obtain an electro - strippable super - hydrophobic composite coating.

[0034] For the super - hydrophobic composite coating prepared according to Example 4, the surface contact angle reaches 165°, the rolling angle reaches 4°, and moreover, when a DC voltage is connected, the peeling behavior of the composite coating can be clearly observed. As shown in Table 4, without power supply, the adhesion of the composite coating can reach 2.72 N / mm 2 . When a 15 V DC voltage is applied across the protective substrate and the super - hydrophobic electronic coating for 2 min continuously, the adhesion of the composite coating is reduced to 0.4 N / mm 2 (The coating thrust test curve is as Figure 2 ). Moreover, the effect of electro - stripping of the composite coating becomes more and more obvious with the increase of voltage and the extension of power - on time. When a 60 V DC voltage is applied for 6 min continuously, the adhesion of the composite coating decays to 0.21 N / mm 2 .

[0035] Table 4 Example 5: A preparation method of an electro - strippable super - hydrophobic composite coating, specifically including the following steps: S1: By weight, add 10 parts of carbon nanotubes to 100 parts of acetone and ultrasonicate for 30 min; under stirring, add 5 parts of 3-aminopropyltrimethoxysilane, stir for 10 h, then add 20 parts of deionized water and stir for 2 h; add 8 parts of polyurethane with a number-average molecular weight of 10000 g·mol -1 After stirring for 15 min, add 8 parts of hexamethylene diisocyanate, and after stirring for 15 min, a superhydrophobic electronic coating is obtained.

[0036] S2: By weight, add 10 parts of lithium bis(trifluoromethanesulfonyl)imide, 30 parts of 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide salt, and 100 parts of hydroxyl-terminated polydimethylsiloxane with a number-average molecular weight of 10000 g·mol -1 to 200 parts of ethyl lactate and stir well to mix evenly; then add 6 parts of methyltrimethoxysilane and 0.5 part of dibutyltin dilaurate, and stir evenly to obtain an ionic coating.

[0037] S3: Using a stainless steel plate as the protective substrate, spray the ionic coating prepared in S2 on its surface and let it stand at room temperature for 2 h; then evenly brush the superhydrophobic electronic coating prepared in S1 on the surface of the ionic coating, and after standing at room temperature for 36 h, a superhydrophobic composite coating that can be peeled off by electrification is obtained.

[0038] Example 6: A method for preparing a superhydrophobic composite coating that can be peeled off by electrification, specifically including the following steps: S1: By weight, add 20 parts of aluminum hydroxide nanoparticles, 1 part of polyvinylpyrrolidone with a number-average molecular weight of 50000 g·mol -1 and 5 parts of carbon nanotubes to 100 parts of toluene and ultrasonicate for 1 h; under stirring, add 1 part of cetyltrimethoxysilane and stir for 24 h; add 10 parts of methyl silicone resin, stir for 30 min, then add 0.5 part of dibutyltin dilaurate and stir for 15 min to obtain a superhydrophobic electronic coating.

[0039] S2: By weight, add 15 parts of 1-vinyl-3-methylimidazolium acryloyloxypropylsulfonate, 100 parts of 1-vinyl-3-butylimidazolium bis(trifluoromethanesulfonyl)imide salt, 15 parts of glycidyl methacrylate, and 2 parts of hydroxybenzophenone to 200 parts of tetrahydrofuran in sequence and dissolve them fully; under the protection of dry inert gas, stir and react under 365 nm ultraviolet light for 30 min, discharge and add 10 parts of 593 curing agent to obtain an ionic coating.

[0040] S3: Using galvanized steel sheet as the protective substrate, brush the ion coating prepared in S2 on its surface, and let it stand at room temperature for 2 h; then uniformly dip-coat the superhydrophobic electronic coating prepared in S1 on the surface of the ion coating, and continue to let it stand at room temperature for 48 h to obtain an electrically strippable superhydrophobic composite coating.

[0041] Example 7: A method for preparing an electrically strippable superhydrophobic composite coating, specifically comprising the following steps: S1: By weight, add 5 parts of silica nanoparticles and 5 parts of graphene into 100 parts of toluene, ultrasonicate for 30 min, and then, under stirring, add 5 parts of heptadecafluorodecyltrimethoxysilane and stir for 36 h; add 10 parts of polyacrylate with a number average molecular weight of 50000 g·mol -1 After stirring for 30 min, add 0.1 part of dibutyltin dilaurate and stir for 10 min to obtain a superhydrophobic electronic coating.

[0042] S2: Mix 10 parts of polyethylene glycol diglycidyl ether with a number average molecular weight of 1000 g·mol -1 10 parts of polypropylene oxide diglycidyl ether with a number average molecular weight of 600 g·mol, 20 parts of 1-butyl-3-methylimidazolium trifluoromethylsulfonate and 100 parts of absolute ethanol uniformly to form a homogeneous transparent solution; then add 50 parts of bisphenol A epoxy resin and 10 parts of ethylenediamine (curing agent), and stir evenly to obtain an ion coating. -1

[0043] S3: Using aluminum plate as the protective substrate, scrape the ion coating prepared in S2 on its surface, cure at 80 °C for 10 min; then uniformly brush the superhydrophobic electronic coating prepared in S1 on the surface of the ion coating, and cure at 80 °C for 4 h to obtain an electrically strippable superhydrophobic composite coating.

[0044] The equipment quantities and processing scales described here are used to simplify the description of the present invention. The applications, modifications, and variations of the present invention are obvious to those skilled in the art.

[0045] Although the embodiments of the present invention have been disclosed as above, it is not limited to only the applications listed in the specification and embodiments. It can be fully applied to various fields suitable for the present invention. For those familiar with the field, additional modifications can be easily achieved. Therefore, without departing from the general concept defined by the claims and the equivalent scope, the present invention is not limited to specific details and the illustrated examples described herein.​

Claims

1. A preparation method of an electro-conductive peelable superhydrophobic composite coating, characterized in that, Comprising: Firstly, an ionic coating is applied on the surface of a protective substrate. After the ionic coating is cured and dried to a certain extent, a superhydrophobic electronic coating is then applied on the surface of the ionic coating. After the ionic coating and the superhydrophobic electronic coating are completely cured and dried, a superhydrophobic composite coating that can be electrically peeled off is obtained.

2. The preparation method of the electro-energizable peelable superhydrophobic composite coating according to claim 1, wherein, The ionic coating is an ionic polymer system with ionic transport ability, a copolymeric ionic polymer system formed by copolymerization of ionic monomers and functional monomers, or a blended ionic polymer system formed by compounding a first matrix polymer, a functional polymer, and an ionic filler; The ionic monomer in the copolymeric ionic polymer system refers to an olefin monomer that can dissociate into anions and cations and contains a carbon-carbon double bond that can undergo free radical polymerization. The carbon-carbon double bond of the olefin monomer can be bonded to an anion or a cation, that is, the free ion is a cation or an anion; The ionic monomer in the copolymeric ionic polymer system is an ionic soft monomer with a glass transition temperature of the homopolymer less than 0 °C or an ionic hard monomer with a glass transition temperature of the homopolymer greater than 0 °C; The functional monomer in the copolymeric ionic polymer system refers to an olefin monomer or a glycerol ether monomer used to adjust the hardness, modulus, adhesion, glass transition temperature of the copolymeric ionic polymer system, or to introduce physical and chemical cross-linking sites in the ionic polymer system; the olefin monomer includes a water-soluble olefin monomer or an oil-soluble olefin monomer, specifically including: styrene, acrylic acid, methacrylic acid, acrylonitrile, acrylate esters, methacrylate esters, vinyl acetate, acrylamide, vinyl pyrrolidone, 2-acrylamido-2-methylpropanesulfonic acid, styrenesulfonic acid, sodium styrenesulfonate, isooctyl acrylate, etc. One or more of them, and the glycerol ether monomers include one or more of polyethylene glycol diglycidyl ether and polypropylene oxide diglycidyl ether; The polymerization method of the copolymeric ionic polymer system includes one or more of bulk polymerization, solution polymerization, emulsion polymerization, suspension polymerization, inverse emulsion polymerization, seed emulsion polymerization, and inverse suspension polymerization; When the copolymeric ionic polymer system is polymerized, the content of the ionic monomer accounts for 10 wt% - 100 wt% of the copolymeric ionic polymer system, and the content of the functional monomer accounts for 0 wt% - 90 wt% of the copolymeric ionic polymer system.

3. The preparation method of the superhydrophobic composite coating that can be peeled off by electrification according to claim 2, characterized in that, The first matrix polymer of the blended ionic polymer system refers to a common high molecular resin with strong adhesion or the copolymeric ionic polymer system described in claim 2. The high molecular resin includes one or more of polyurethane, epoxy resin, phenolic resin, polyester resin, acrylic resin, silicone resin, polyamide, polyimide, polyvinyl alcohol, polyvinyl chloride resin, bisphenol A epoxy resin, fluorophosphate resin, etc.

4. The preparation method of the superhydrophobic composite coating capable of being peeled off by electrification according to claim 2, wherein, The functional polymer in the blend-type ionomer system refers to a polymer material or a copolymer-type ionomer system that has ion complexation sites and can improve the ion transport performance of the blend-type ionomer system. The polymer material includes one or more of polylactic acid, polyethylene oxide, polypropylene oxide, polyacrylonitrile, polytetrafluoroethylene, polyvinylidene fluoride, polyacrylate, polydimethylsiloxane, polycaprolactone, polyethyl carbonate, polypropyl carbonate, trimethyl carbonate, and polyether polyol. The dosage of the functional polymer accounts for 5 wt% - 50 wt% of the blend-type ionomer system.

5. The preparation method of the superhydrophobic composite coating capable of being stripped by electrification according to claim 2, wherein, The ion filler in the blend-type ionomer system refers to an organic salt or an inorganic salt that can dissociate into free anions and free cations, including ionic liquids, organometallic salts, inorganic metal salts, and deep eutectic solvents. The ion filler is a single ion filler or a combination of multiple ion fillers, and the dosage of the ion filler accounts for 5 wt% - 50 wt% of the blend-type ionomer system.

6. The preparation method of the superhydrophobic composite coating capable of being electrically stripped as described in claim 2, characterized in that, Solvent 1 is introduced into the copolymer-type ionomer system and the blend-type ionomer system in the ion coating. Solvent 1 includes one or more of water, benzene, toluene, methanol, ethanol, propanol, acetone, acetonitrile, acetic acid, hexane, heptane, chloroform, n-butanol, isopentane, n-pentane, cyclopentane, petroleum ether, cyclohexane, ethyl acetate, butyl acetate, trifluoroacetic acid, ethyl acetate, butyl acetate. The internal cross-linking method of the copolymer-type ionomer system and the blend-type ionomer system is a thermosetting type with chemical cross-linking or a thermoplastic type with only physical cross-linking without chemical cross-linking. The coating and processing method of the ion coating on the surface of the protective substrate is any one or more of brushing, scraping, spraying, or dipping. The protective substrate refers to a metal substrate or an electronically conductive substrate, including one of copper, iron, magnesium, zinc, nickel, beryllium, tungsten, stainless steel, metal alloy, and polymer conductive composite material. If the surface of the protective substrate is not electronically conductive, conductive treatment is required. The curing and drying method of the ion coating includes standing at room temperature, air drying, heating, radiation, and ultraviolet irradiation. The ion coating is cured and dried to a certain extent, which means that the bulk viscosity of the ion coating reaches more than 5000 mPa·s. The ion transport ability of the ion coating refers to that the ionic conductivity of the ion coating after complete curing and drying is greater than 1×10 -6 S / cm.

7. The preparation method of the superhydrophobic composite coating that can be peeled off by electrification according to claim 1, characterized in that, The superhydrophobic electronic coating is obtained by compounding a second matrix polymer and an electronic filler. Solvent 2 is introduced during the compounding process of the second matrix polymer and the electronic filler. Solvent 2 includes one or more of water, benzene, toluene, methanol, ethanol, propanol, acetone, acetonitrile, acetic acid, hexane, heptane, chloroform, n-butanol, isopentane, n-pentane, cyclopentane, petroleum ether, cyclohexane, ethyl acetate, butyl acetate, trifluoroacetic acid, ethyl acetate, butyl acetate. The second matrix polymer of the superhydrophobic electronic coating refers to a high molecular resin material with strong adhesion, including: polyurethane, epoxy resin, phenolic resin, polyester resin, acrylic resin, silicone resin, polyamide, polyimide, polyvinyl alcohol, polyvinyl chloride, bisphenol A epoxy resin, methyl silicone resin, or one or more of them; the dosage of the second matrix polymer accounts for 0 wt% - 50 wt% of the superhydrophobic electronic coating; The electronic filler of the superhydrophobic electronic coating refers to a micro-nano material or high molecular material with electronic conduction ability, including: acetic acid, ammonia water, conductive graphite, conductive carbon black, reduced graphene oxide, graphene, carbon nanotubes, metal nanowires, metal micro-nano powders, metal alloy micro-nano powders, conductive metal oxides, conductive polymers, liquid metals, or one or more of them; the metal micro-nano powders include one or more of gold powder, silver powder, magnesium powder, aluminum powder, zinc powder; the metal alloy micro-nano powders include one or more of magnesium-aluminum alloy powder, zinc-magnesium alloy powder, magnesium-aluminum-zinc alloy powder, zinc-aluminum alloy powder, copper-silver alloy powder, nickel-copper alloy powder; the conductive metal oxides include one or more of antimony-doped tin dioxide, aluminum-doped zinc oxide, indium-doped tin oxide; the conductive polymers include one or more of doped polyaniline, doped polypyrrole, doped polythiophene; the liquid metals include one or more of indium-tin alloy, gallium-tin alloy, gallium-indium-tin alloy; the dosage of the electronic filler accounts for 0 wt% - 50 wt% of the superhydrophobic electronic coating.

8. The preparation method of the superhydrophobic composite coating capable of being electrically peeled as claimed in claim 7, wherein, The electronic filler of the superhydrophobic electronic coating is hydrophobically modified by a hydrophobic modifier, and the hydrophobic modifier includes: 1H,1H,2H,2H-perfluorodecyltriethoxysilane, heptadecafluorodecyltrimethoxysilane, 3-aminopropyltrimethoxysilane, cetyltrimethoxysilane, fluorosilane, trifluorochlorosilane, polytetrafluoroethylene, n-octyltrifluorochlorosilane, cycloalkylsilane, hexamethyldisiloxane, polymethylhydrosiloxane, tetrabutyl titanate, or one or more of them; Non-conductive nano-fillers are introduced into the superhydrophobic electronic coating, and the non-conductive nano-fillers include: silica nanoparticles, alumina nanoparticles, zinc oxide nanoparticles, titanium oxide nanoparticles, polystyrene microspheres, or one or more of them; the dosage of the non-conductive nano-fillers accounts for 0 wt% - 20 wt% of the superhydrophobic electronic coating.

9. The preparation method of the electroconductive strippable superhydrophobic composite coating according to claim 1, characterized in that, The coating method of the superhydrophobic electronic coating on the surface of the ion coating is one or more of brushing, scraping, spraying, or dipping; The curing and drying method of the superhydrophobic electronic coating includes one of normal temperature static setting, air drying, heating, radiation, or ultraviolet irradiation; The electronic transmission ability of the superhydrophobic electronic coating means that the electronic conductivity of the superhydrophobic electronic coating after complete curing and drying is less than 0.01 S / m.

10. The preparation method of the electroconductive strippable superhydrophobic composite coating according to claim 1, characterized in that, The energization of the electrically detachable refers to applying a voltage on both sides of the protective substrate and the superhydrophobic electronic coating, the applied voltage is direct current or alternating current, the magnitude of the applied voltage is 6 - 150V, and the energization time is 0 - 120 min; The peelable property by electrification mentioned above means that the adhesion reduction ratio of the ionic coating before and after electrification is greater than 50%, so as to facilitate the rapid peeling of the ionic coating and the superhydrophobic electronic coating from the substrate.

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