Preparation method of anti-frosting super-hydrophobic coating with armor structure

Abstract

The invention discloses a preparation method of an anti-frosting super-hydrophobic coating of an armor structure, and belongs to the technical field of surface protection, and the preparation method comprises the following steps: step 1, taking an aluminum sheet, grinding and polishing the aluminum sheet, then placing the aluminum sheet in a cleaning solution for ultrasonic degreasing, and drying after ultrasonic treatment is completed; 2, the dried aluminum sheet, deionized water, a zinc ion solution and an alkaline solution are placed in a high-pressure reaction kettle, pH is adjusted, and an armor structure is formed on the aluminum sheet; 3, the high-pressure reaction kettle is taken out and cooled to the room temperature, the aluminum sheet is taken out and placed in a cleaning solution to be subjected to ultrasonic cleaning, and the aluminum sheet with the Zn-Al LDH film of the armor structure is obtained and placed in a drying oven to be dried for use; and 4, the treated aluminum sheet with the Zn-Al LDH film of the armor structure is subjected to hydrophobic treatment through an electro-deposition method. According to the preparation method of the anti-frosting super-hydrophobic coating with the armor structure, the operation time is greatly saved, and the operation process is safe, stable and controllable.

Description

Technical Field

[0001] The present invention relates to the technical field of surface protection, and particularly to a preparation method of a frost - resistant super - hydrophobic coating with an armor structure. Background Art

[0002] In the fields of refrigeration and air - conditioning, frosting is inevitable. Frosting will seriously affect the operating efficiency of equipment and also result in huge defrosting energy consumption. In addition, the frost layer will block the fin gaps, leading to a reduction in the heat transfer of the air flow and ultimately reducing the operating efficiency of refrigeration equipment. Research has found that the surface hydrophobic technology is an effective way to improve the energy efficiency of refrigeration and air - conditioning systems under frosting conditions. Summary of the Invention

[0003] The purpose of the present invention is to provide a preparation method of a frost - resistant super - hydrophobic coating with an armor structure, and the prepared super - hydrophobic coating has the characteristics of corrosion resistance, strong durability and excellent frost - resistant properties.

[0004] To achieve the above - mentioned purpose, the present invention provides a preparation method of a frost - resistant super - hydrophobic coating with an armor structure, comprising the following steps:

[0005] Step 1: Take an aluminum sheet, polish the aluminum sheet, and then place the aluminum sheet in a cleaning solution for ultrasonic degreasing. After ultrasonic treatment, it is dried.

[0006] Step 2: Place the dried aluminum sheet, deionized water, zinc ion solution and alkaline solution in a high - pressure reactor, adjust the pH to form an armor structure on the aluminum sheet.

[0007] Step 3: Take out the completely reacted high - pressure reactor and cool it to room temperature. Take out the aluminum sheet and place it in a cleaning solution for ultrasonic cleaning to prepare a Zn - Al LDH film with an armor structure on the aluminum sheet, and then put it in an oven for drying for standby.

[0008] Step 4: Use the electrodeposition method to perform hydrophobic treatment on the aluminum sheet obtained in Step 3 to prepare a super - hydrophobic coating on the surface of the aluminum sheet.

[0009] Preferably, in Step 1, the aluminum sheet is polished with 80 - 1200 - mesh sandpaper, the cleaning solution is one or more of acetone, ethanol and water, the ultrasonic time is 5 - 15 min, and the drying operation is: drying by a blower.

[0010] Preferably, in Step 1, the aluminum sheet is polished with 600 - 1200 - mesh sandpaper, and the cleaning solution is sequentially selected as acetone, ethanol and water for cleaning.

[0011] Preferably, in step two, the zinc ion solution is one or more of zinc acetate, zinc nitrate, and zinc chloride, the concentration of the zinc ion solution is 1-30 mmol / L, the alkaline solution is one or more of sodium carbonate, sodium bicarbonate, ammonia water, and sodium hydroxide, and the pH is adjusted to 8-14.

[0012] Preferably, in step two, the concentration of the zinc ion solution is 10-15 mmol / L, and the pH is adjusted to 10-12.

[0013] Preferably, in step three, the reaction time is 1-5 h, the reaction temperature is 50-100 °C, and the cleaning solution is one or more of deionized water, ethanol, acetone, and ethyl acetate.

[0014] Preferably, in step three, the reaction time is 2-3 h, and the cleaning solution is deionized water.

[0015] Preferably, the specific operation of step four is as follows: Dissolve the cerium salt and stearic acid in a solvent, and after complete stirring, obtain a uniform and transparent electrolyte solution. Use ordinary aluminum sheets as the anode and the aluminum sheets obtained in step three as the cathode for electrodeposition. After the reaction is completed, clean with a cleaning agent, and then dry and cool to prepare a superhydrophobic coating on the aluminum sheet.

[0016] Preferably, in step four, the cerium salt is one of cerium chloride heptahydrate, cerium nitrate hexahydrate, and cerium sulfate octahydrate, the concentration of the cerium salt is 0.1-0.5 mol / L, the solvent is one of water and ethanol, the electrodeposition voltage is 15-50 V, the electrode spacing is 1-5 cm, the reaction temperature is 30-60 °C, and the reaction time is 20-60 min.

[0017] Preferably, in step four, the concentration of the cerium salt is 0.2 mol / L, the electrodeposition voltage is 20-40 V, the electrode spacing is 2-3 cm, the reaction temperature is 40-50 °C, and the reaction time is 30-45 min.

[0018] Therefore, the preparation method of the anti-frosting superhydrophobic coating with the above-mentioned armor structure of the present invention has the following beneficial effects:

[0019] (1) Using a controllable, environmentally friendly, and safe hydrothermal method to prepare an armor friction-resistant structure, and then combining the electrodeposition method to prepare a superhydrophobic coating with an armor ball stacking structure on the substrate surface, which greatly saves the operation time and realizes the safety, stability, and controllability of the operation process;

[0020] (2) After combining electrodeposition, an armor ball stacking structure is formed on the surface of the coating, showing extremely excellent superhydrophobic performance, showing a very high water contact angle and a very low rolling angle. In addition, due to its extremely low surface energy and micro-nano secondary structure, pollutants are difficult to adhere, showing excellent self-cleaning ability;

[0021] (3) Under the support and protection of the armor ball stacking structure, the superhydrophobic coating exhibits excellent durability and corrosion resistance, and has extremely wide applications in fields such as anti-corrosion industrial components, air conditioner anti-icing and anti-frosting, and biomedical devices.

[0022] The technical solutions of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Description of the Drawings

[0023] Figure 1 is the preparation flow chart of Example 1 of the preparation method of the anti-frosting superhydrophobic coating with an armor structure of the present invention;

[0024] Figure 2 is the microscopic morphology diagram of the Zn-Al LDH film with an armor structure and the superhydrophobic coating prepared on an aluminum sheet in Step 3 of Example 1 of the preparation method of the anti-frosting superhydrophobic coating with an armor structure of the present invention;

[0025] Figure 3 is the surface roughness analysis diagram of the aluminum sheet with a superhydrophobic coating and the polished aluminum sheet prepared in Example 1 of the preparation method of the anti-frosting superhydrophobic coating with an armor structure of the present invention;

[0026] Figure 4 is the infrared spectrum and element analysis diagram of the superhydrophobic coating prepared in Example 1 of the preparation method of the anti-frosting superhydrophobic coating with an armor structure of the present invention and the element analysis diagram of the Zn-Al LDH film with an armor structure;

[0027] Figure 5 is the self-cleaning performance test diagram of the aluminum sheet with a superhydrophobic coating and the polished aluminum sheet prepared in Example 1 of the preparation method of the anti-frosting superhydrophobic coating with an armor structure of the present invention;

[0028] Figure 6 is the mechanical durability test diagram of the superhydrophobic coating prepared in Example 1 of the preparation method of the anti-frosting superhydrophobic coating with an armor structure of the present invention;

[0029] Figure 7 is the microscopic morphology diagram of the superhydrophobic coating after 60 times of repeated tape peeling prepared in Example 1 of the preparation method of the anti-frosting superhydrophobic coating with an armor structure of the present invention;

[0030] Figure 8 is the surface frosting test diagram of the aluminum sheet with a superhydrophobic coating and the pure aluminum sheet prepared in Example 1 of the preparation method of the anti-frosting superhydrophobic coating with an armor structure of the present invention. Detailed Embodiments

[0031] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0032] Unless otherwise defined, the technical terms or scientific terms used in the present invention shall have the ordinary meanings understood by those of ordinary skill in the field to which the present invention pertains.

[0033] The present invention provides a method for preparing a frost-resistant superhydrophobic coating with an armor structure, comprising the following steps:

[0034] Step 1: Take an aluminum sheet and polish it with sandpaper of 80 - 1200 mesh, preferably polish it with sandpaper of 600 - 1200 mesh. Then place the aluminum sheet in a cleaning solution for ultrasonic degreasing. The cleaning solution is one or more of acetone, ethanol, and water. Preferably, acetone, ethanol, and deionized water are selected in sequence for cleaning. The ultrasonic time is 5 - 15 min. After ultrasonic cleaning, dry it with a blower;

[0035] Step 2: Place the dried aluminum sheet, deionized water, zinc ion solution, and alkaline solution in a high-pressure reactor, adjust the pH, and form an armor structure on the aluminum sheet. Among them, the zinc ion solution is one or more of zinc acetate, zinc nitrate, and zinc chloride, the concentration of the zinc ion solution is 1 - 30 mmol / L, preferably 10 - 15 mmol / L, the alkaline solution is one or more of sodium carbonate, sodium bicarbonate, ammonia water, and sodium hydroxide, and adjust the pH to 8 - 14, preferably adjust the pH to 10 - 12.

[0036] Step 3: Take out the completely reacted high-pressure reactor and cool it to room temperature. The reaction time is 1 - 5 h, the reaction temperature is 50 - 100 °C, preferably the reaction time is 2 - 3 h. Take out the aluminum sheet in the reactor and place it in a cleaning solution for ultrasonic cleaning. The cleaning solution is one or more of deionized water, ethanol, acetone, and ethyl acetate. Preferably, it is deionized water. A Zn-Al LDH film with an armor structure is prepared on the aluminum sheet and dried in an oven for standby;

[0037] Step 4: Perform hydrophobic treatment on the aluminum sheet obtained in Step 3 by electrodeposition to obtain a superhydrophobic coating. The specific operation is as follows: Dissolve cerium salt and stearic acid in a solvent, and after complete stirring, obtain a uniform and transparent electrolyte solution. Use a common aluminum sheet as the anode and the aluminum sheet obtained in Step 3 as the cathode for electrodeposition. After the reaction, clean it with a cleaning agent, then dry and cool it to prepare a superhydrophobic coating on the aluminum sheet.

[0038] The cerium salt is one of cerium chloride heptahydrate, cerium nitrate hexahydrate, and cerium sulfate octahydrate. The concentration of the cerium salt is 0.1 - 0.5 mol / L, the solvent is one of water and ethanol, the electrodeposition voltage is 15 - 50 V, the electrode spacing is 1 - 5 cm, the reaction temperature is 30 - 60 °C, and the reaction time is 20 - 60 min.

[0039] Preferably, the cerium salt concentration is 0.2 mol / L, the electrodeposition voltage is 20 - 40 V, the electrode spacing is 2 - 3 cm, the reaction temperature is 40 - 50 °C, and the reaction time is 30 - 45 min.

[0040] Example 1

[0041] As Figure 1 shown, the present invention provides a method for preparing an anti - frosting super - hydrophobic coating with an armor structure, comprising the following steps:

[0042] Step 1: Take an aluminum sheet, and polish the aluminum sheet successively with 600#, 800#, 1000#, and 1200# sandpapers to remove surface grease and oxide layer. Subsequently, place the aluminum sheet in acetone, ethanol, and deionized water successively for ultrasonic degreasing within 10 min, and then dry it with a blower;

[0043] Step 2: Put the treated aluminum sheet, deionized water, 10 mmol / L zinc acetate solution, and ammonia water into a stainless - steel autoclave with a polytetrafluoroethylene inner liner, adjust the pH to 10.7 and then react to form an armor structure;

[0044] Step 3: React at 60 °C for 2 h, take out the completely reacted autoclave, cool it to room temperature, take out the aluminum sheet and place it in deionized water for ultrasonic cleaning, prepare a Zn - Al LDH film with an armor structure on the aluminum sheet, and put it in an oven at 60 °C for drying for later use;

[0045] Step 4: Dissolve 2.16 g of cerium nitrate hexahydrate and 2.84 g of stearic acid in 100 mL of ethanol, stir with a magnetic stirrer until completely dissolved to obtain a uniform and transparent electrolyte solution. Use a common aluminum sheet as the anode and the aluminum sheet obtained in Step 3 as the cathode, and carry out electrochemical deposition for 30 min under the reaction conditions of a constant voltage of 30 V, an electrode spacing of 2 cm, and a temperature of 40 °C. After the reaction, rinse the treated aluminum sheet with ethanol, and finally dry it in a drying oven at 60 °C for 4 h. Take it out, clean it with a cleaning agent, and then dry and cool it to room temperature to prepare a super - hydrophobic coating on the aluminum sheet.

[0046] Example 2

[0047] The present invention provides a method for preparing an anti - frosting super - hydrophobic coating with an armor structure, comprising the following steps:

[0048] Step 1: Take an aluminum sheet, and polish the aluminum sheet successively with 600#, 800#, 1000#, and 1200# sandpapers to remove surface grease and oxide layer. Subsequently, place the aluminum sheet in acetone, ethanol, and deionized water successively for ultrasonic degreasing within 10 min, and then dry it with a blower;

[0049] Step 2: Put the treated aluminum sheet, deionized water, 10 mmol / L zinc chloride solution and ammonia water into a stainless steel high-pressure reactor with a polytetrafluoroethylene inner liner. Adjust the pH to 10.7 and then react to form an armor structure.

[0050] Step 3: React at 60 °C for 2 h. Take out the completely reacted reactor, cool it to room temperature, take out the aluminum sheet and ultrasonically clean it in deionized water. A Zn-Al LDH film with an armor structure is prepared on the aluminum sheet and placed in an oven at 60 °C for drying for later use.

[0051] Step 4: Dissolve 2.16 g of cerium nitrate hexahydrate and 2.84 g of stearic acid in 100 mL of ethanol, and stir with a magnetic stirrer until completely dissolved to obtain a uniform and transparent electrolyte solution. Use a common aluminum sheet as the anode and the aluminum sheet obtained in Step 3 as the cathode, and carry out electrochemical deposition for 30 min under the reaction conditions of a constant voltage of 30 V, an electrode spacing of 2 cm, and a temperature of 40 °C. After the reaction is completed, rinse the treated aluminum sheet with ethanol, and finally dry it in a drying oven at 60 °C for 4 h. Take it out, clean it with a cleaning agent, and then dry and cool it to room temperature. A superhydrophobic coating is prepared on the aluminum sheet.

[0052] Example 3

[0053] The present invention provides a method for preparing an anti-frost superhydrophobic coating with an armor structure, including the following steps:

[0054] Step 1: Take an aluminum sheet and polish it successively with 600#, 800#, 1000#, and 1200# sandpapers to remove the surface grease and oxide layer. Subsequently, place the aluminum sheet in acetone, ethanol, and deionized water successively and carry out degreasing by ultrasonic cleaning within 10 min, and then dry it with a blower.

[0055] Step 2: Put the treated aluminum sheet, deionized water, 10 mmol / L zinc acetate solution and ammonia water into a stainless steel high-pressure reactor with a polytetrafluoroethylene inner liner. Adjust the pH to 10.7 and then react to form an armor structure.

[0056] Step 3: React at 60 °C for 2 h. Take out the completely reacted reactor, cool it to room temperature, take out the aluminum sheet and ultrasonically clean it in deionized water to obtain an aluminum sheet with a Zn-Al LDH film having an armor structure, and place it in an oven at 60 °C for drying for later use.

[0057] Step 4: Dissolve 2.16 g of cerium nitrate hexahydrate and 2.84 g of stearic acid in 100 mL of ethanol, and stir with a magnetic stirrer until completely dissolved to obtain a homogeneous and transparent electrolyte solution. Use a common aluminum sheet as the anode and the aluminum sheet obtained in Step 3 as the cathode, and carry out electrochemical deposition for 30 min under the reaction conditions of a constant voltage of 40 V, an electrode spacing of 3 cm, and a temperature of 40 °C. After the reaction, rinse the treated aluminum sheet with ethanol, and finally dry it in an oven at 60 °C for 4 h. Take it out and clean it with a cleaning agent, and then dry and cool it to room temperature to prepare a superhydrophobic coating on the aluminum sheet.

[0058] Example 4

[0059] The present invention provides a method for preparing an anti-frosting superhydrophobic coating with an armor structure, including the following steps:

[0060] Step 1: Take an aluminum sheet, polish the aluminum sheet successively with 600#, 800#, 1000#, and 1200# sandpapers to remove the surface grease and oxide layer. Subsequently, place the aluminum sheet in acetone, ethanol, and deionized water in turn and carry out degreasing by ultrasonic wave within 10 min, and then dry it with a blower;

[0061] Step 2: Put the treated aluminum sheet, deionized water, 10 mmol / L zinc acetate solution, and ammonia water into a stainless steel autoclave with a polytetrafluoroethylene inner liner, adjust the pH to 10.7 and then react to form an armor structure;

[0062] Step 3: React at 60 °C for 2 h, take out the completely reacted autoclave, cool it to room temperature, take out the aluminum sheet and place it in deionized water for ultrasonic cleaning, prepare a Zn-Al LDH film with an armor structure on the aluminum sheet, and put it in an oven at 60 °C for drying for later use;

[0063] Step 4: Dissolve 2.16 g of cerium chloride hexahydrate and 2.84 g of stearic acid in 100 mL of ethanol, and stir with a magnetic stirrer until completely dissolved to obtain a homogeneous and transparent electrolyte solution. Use a common aluminum sheet as the anode and the aluminum sheet obtained in Step 3 as the cathode, and carry out electrochemical deposition for 30 min under the reaction conditions of a constant voltage of 30 V, an electrode spacing of 2 cm, and a temperature of 40 °C. After the reaction, rinse the treated aluminum sheet with ethanol, and finally dry it in an oven at 60 °C for 4 h. Take it out and clean it with a cleaning agent, and then dry and cool it to room temperature to prepare a superhydrophobic coating on the aluminum sheet.

[0064] Performance test:

[0065] I. Microscopic morphology characterization

[0066] Use a scanning electron microscope (SEM) to characterize the microscopic morphology of the superhydrophobic coating prepared in Example 1. Figure 2Microscopic morphology diagrams of the Zn-Al LDH film with an armor structure and the superhydrophobic coating prepared on the aluminum sheet in Step 3 of Example 1: Among them, Figure 2 Figure (a) in Figure 2 is a low-magnification SEM image of the Zn-Al LDH film with an armor structure; Figure 2 Figure (b) in Figure 2 is a high-magnification SEM image of the Zn-Al LDH film with an armor structure; Figure 2 Figure (c) in Figure 2 is a low-magnification SEM image of the superhydrophobic coating;

[0067] Figure 3 Figure (d) in Figure 3 is an enlarged view of the clusters and spherical protrusion-like structures on the surface of the superhydrophobic coating. It can be seen from the figure that obvious changes have occurred on the surface of the substrate after hydrothermal synthesis. Due to mutual compression during the growth process, a stable rough structure of micron-scale armor rod-like accumulation has formed on the surface of the substrate. From Figure 3 Figure (c) in Figure 3 and Figure 3 Figure (d) in

[0068] Figure 4 it can be seen that after cathodic electrodeposition, spherical papilla structures appear on the surface, indicating that low-surface-energy substances have successfully adhered to the Zn-Al LDH film. The sizes of these structures range from a few hundred nanometers to a few micrometers, and they aggregate with each other to form clusters. A large amount of air is filled between these clusters, thereby significantly reducing the liquid-solid contact area of water droplets on the surface.

[0067] Figure 3 Surface roughness analysis diagrams of the aluminum sheet with a superhydrophobic coating and the polished aluminum sheet in Example 1, where Figure 3 Figure (a) in Figure 3 is a 3D image of the surface of the polished aluminum sheet, Figure 3 Figure (b) in Figure 3 is a plan view of the surface of the polished aluminum sheet,

[0068] Figure 4 Figure (c) in Figure 4 is a 3D image of the surface of the aluminum sheet with a superhydrophobic coating,Figure 4 (b) is the EDS spectrum of the Zn-Al LDH film surface. Figure 4 (c) is the EDS spectrum of the super-hydrophobic coating. It can be seen from the figure that at 2917 cm -1 and 2853cm -1 The asymmetric stretching vibration peak and antisymmetric stretching vibration peak of the CH bond in stearic acid are shown at the surface, and the infrared test of the super-hydrophobic coating also shows this characteristic peak, indicating that the surface of the super-hydrophobic coating contains stearic acid. Through EDS energy spectrum analysis, it can be seen that after the hydrothermal reaction, the main elements on the surface are Zn, Al, C, and O, which mainly come from the Zn-Al LDH film; after electrochemical deposition, the main elements on the surface are Zn, Al, C, O, and Ce, and the proportion of C increases significantly, indicating that cerium stearate is successfully grown on the Zn-Al LDH film.

[0069] 2. Contact angle test

[0070] The contact angle of the aluminum sheet with super-hydrophobic coating in Example 1 was measured using an OCA25 contact angle meter, with a measurement range of 0-180°, a contact angle resolution of 0.01°, and a measurement accuracy of ±0.1°. Special note: Due to the complex structure of the corrugated fin plate, friction resistance test cannot be performed. After the test, it was shown that the contact angle of the super-hydrophobic coating reached 157.2°±4°, indicating that the super-hydrophobic coating has excellent hydrophobicity and self-cleaning properties.

[0071] Figure 5 This is a self-cleaning performance test diagram of the aluminum sheet with super-hydrophobic coating and the polished aluminum sheet prepared in Example 1, wherein Figure 5 (a) is a self-cleaning test of the surface of an aluminum sheet with a super-hydrophobic coating at different times. Figure 5 (b) in the figure is a self-cleaning test of the surface of the polished aluminum sheet at different times. It can be seen from the figure that under the impact of water flow, the pollutants of the super-hydrophobic coating can be easily detached; and the cleaning experiment of the polished aluminum sheet found that the water droplets were not easy to fall off the surface of the polished aluminum sheet. When there are enough water droplets, due to gravity, the water takes away some of the pollutants, but there are still a large number of pollutants trapped on the surface of the polished aluminum sheet. Due to the extremely low surface energy and its micro-nano secondary structure, the super-hydrophobic coating makes it difficult for pollutants to adhere to the surface. After the water flow passes, the pollutants will be taken away by the water flow to restore the surface to clean, showing excellent self-cleaning properties; relatively speaking, the surface of the polished aluminum sheet has a relatively high adhesion, so that a large number of pollutants are retained on the surface.

[0072] 3. Mechanical durability test

[0073] The mechanical durability of the superhydrophobic coating obtained in Example 1 was characterized by tape peeling and sandpaper rubbing over a quantitative distance, and the contact angle after the test was recorded until the contact angle was lower than 150°. Figure 6 Figure for the mechanical durability test of the superhydrophobic coating prepared in Example 1, where Figure 6 (a) in it is the figure for the mechanical durability test of the aluminum sheet with the superhydrophobic coating after 60 tape peelings, Figure 6 (b) in it is the figure for the mechanical durability test of the aluminum sheet with the superhydrophobic coating after 30 sanding tests. It can be seen from the figure that after 60 tape peelings, the surface hydrophobic angle reaches 144.4°, still having hydrophobicity; after 30 sanding tests, the contact angle on the material surface decreases to 145.5°, still retaining hydrophobicity.

[0074] Figure 7 Figure for the microscopic morphology of the superhydrophobic coating prepared in Example 1 after 60 repeated tape peelings: where Figure 7 (a) in it is the worn surface at high magnification; Figure 7 (b) in it is the worn surface at low magnification. It can be seen from the figure that the armor structure formed by the hydrothermal reaction is worn, exposing part of the cross-section. At the same time, the spherical low-surface-energy substances are worn, but there are still some low-surface-energy substances in the gaps of the armor structure (substances within the red circle), so that the worn surface still has a certain degree of hydrophobicity.

[0075] IV. Surface frosting test

[0076] The test sample was placed on a cold stage with a surface temperature of -10 °C, and the temperature of the cold stage was kept constant, and the surface of the sample was photographed. Figure 8 Figure for the surface frosting test of the aluminum sheet with the superhydrophobic coating prepared in Example 1 and the pure aluminum sheet, where Figure 8 (a) in it is the experimental figure for surface frosting of the pure aluminum sheet, Figure 8 (b) in it is the experimental figure for surface frosting of the superhydrophobic coating. It can be seen from the figure that a relatively obvious frost layer has appeared on the surface of the pure aluminum sheet at 3 minutes. As time increases, the frost layer begins to thicken continuously and becomes compact; while for the superhydrophobic coating, at 30 minutes, one-third of the area still has no frosting but forms many droplets. The trajectory of small droplets bouncing and merging into large droplets can be clearly seen in the dotted circle, and the dry surface is exposed, indicating that the phenomenon of droplet bouncing further enhances the anti-frosting effect.

[0077] Therefore, the present invention adopts the above preparation method of an anti-frosting superhydrophobic coating with an armor structure, and uses electrodeposition to prepare a superhydrophobic coating with an armor structure on the substrate surface, greatly saving the operation time and realizing the safety, stability and controllability of the operation process.

[0078] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions of the present invention or make equivalent replacements, and these modifications or equivalent replacements cannot make the modified technical solutions deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for preparing an anti-frost super-hydrophobic coating for an armor structure, characterized in that: The following steps are involved: Step 1: Take an aluminum sheet, grind and polish it, then place the aluminum sheet in a cleaning solution for ultrasonic degreasing, and dry it after the ultrasonic treatment; Step 2: placing the dried aluminum sheet, deionized water, zinc ion solution and alkaline solution in a high-pressure reactor, adjusting the pH, and forming an armor structure on the aluminum sheet; Step 3, take out the high-pressure reactor after the reaction is completed, cool it to room temperature, take out the aluminum sheet and place it in a cleaning solution for ultrasonic cleaning, prepare a Zn-AlLDH film with an armor structure on the aluminum sheet, and put it in an oven to dry for later use; Step 4: The aluminum sheet obtained in step 3 is subjected to a hydrophobic treatment by an electrodeposition method to prepare a super-hydrophobic coating on the surface of the aluminum sheet.

2. The method for preparing an anti-frost super-hydrophobic coating for an armor structure according to claim 1, characterized in that: In step 1, the aluminum sheet is polished with sandpaper of 80-1200 mesh, the cleaning solution is one or more of acetone, ethanol and water, the ultrasonic time is 5-15 minutes, and the drying operation is: drying by a blower.

3. The method for preparing an anti-frost super-hydrophobic coating of an armor structure according to claim 2, characterized in that: In step 1, the aluminum sheet is polished using 600-1200 mesh sandpaper, and acetone, ethanol and water are selected as cleaning fluids in turn for cleaning.

4. The method for preparing an anti-frost super-hydrophobic coating for an armor structure according to claim 1, characterized in that: In step 2, the zinc ion solution is one or more of zinc acetate, zinc nitrate and zinc chloride, the concentration of the zinc ion solution is 1-30 mmol / L, the alkaline solution is one or more of sodium carbonate, sodium bicarbonate, ammonia water and sodium hydroxide, and the pH is adjusted to 8-14.

5. The method for preparing an anti-frost super-hydrophobic coating for an armor structure according to claim 4, characterized in that: In step 2, the concentration of the zinc ion solution is 10-15 mmol / L, and the pH is adjusted to 10-12.

6. The method for preparing an anti-frost super-hydrophobic coating for an armor structure according to claim 1, characterized in that: In step three, the reaction time is 1-5 hours, the reaction temperature is 50-100° C., and the cleaning solution is one or more of deionized water, ethanol, acetone and ethyl acetate.

7. The method for preparing an anti-frost super-hydrophobic coating for an armor structure according to claim 6, characterized in that: In step 3, the reaction time is 2-3 hours, and the cleaning solution is deionized water.

8. The method for preparing an anti-frost super-hydrophobic coating for an armor structure according to claim 1, characterized in that: The specific operation of step four is: dissolving the cerium salt and stearic acid in a solvent, stirring thoroughly to obtain a uniform and transparent electrolyte solution, using an ordinary aluminum sheet as an anode and the aluminum sheet obtained in step three as a cathode for electrodeposition, and after the reaction is completed, using a cleaning agent to clean, then drying and cooling, to prepare a super-hydrophobic coating on the aluminum sheet.

9. The method for preparing an anti-frost super-hydrophobic coating for an armor structure according to claim 8, characterized in that: In step 4, the cerium salt is one of cerium chloride heptahydrate, cerium nitrate hexahydrate and cerium sulfate octahydrate, the cerium salt concentration is 0.1-0.5 mol / L, the solvent is one of water and ethanol, the electrodeposition voltage is 15-50V, the electrode spacing is 1-5cm, the reaction temperature is 30-60°C, and the reaction time is 20-60min.

10. The method for preparing an anti-frost super-hydrophobic coating for an armor structure according to claim 9, characterized in that: In step 4, the concentration of cerium salt is 0.2 mol / L, the electrodeposition voltage is 20-40 V, the electrode spacing is 2-3 cm, the reaction temperature is 40-50° C., and the reaction time is 30-45 min.

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