An ice-repellent and ice-phobic composite surface and a preparation method thereof

Abstract

The application is an ice-preventing and ice-repellent composite surface and a preparation method thereof, and belongs to the field of ice-preventing and ice-repellent. The surface comprises a porous material base, super-hydrophobic / oleophobic lubricating fluid top microstructure coupled to the surface of the base, and hydrophobic / oleophilic lubricating fluid internal microstructure, wherein the surface of the hydrophobic / oleophilic lubricating fluid internal microstructure is injected with lubricating fluid; the super-hydrophobic / oleophobic lubricating fluid top microstructure is located on the surface of a plurality of columnar bodies arranged in an array on the porous material base, i.e. has super-hydrophobic characteristics for water and lubricating fluid; and the hydrophobic / oleophilic lubricating fluid internal microstructure is also arranged in an array and surrounds the root of each columnar body, and has oleophilic lubricating fluid and hydrophobic characteristics. The surface of the application can simultaneously have the ice-preventing and ice-repellent performance of super-hydrophobic and super-smooth characteristics, i.e. can have the excellent ice-preventing performance of a super-hydrophobic surface, and can also repel ice like a super-smooth surface after the surface is iced, so that the ice is easier to remove.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of anti-icing and de-icing, and particularly relates to an anti-icing and de-icing composite surface and a preparation method. BACKGROUND

[0002] Ice formation is very common in life, but it can cause great safety problems in the fields of aviation, navigation, etc. For example, high-altitude icing of a wing can cause an airplane to stall and result in an aviation accident, and icing of a long-distance freighter can affect normal navigation. A super-hydrophobic surface is a surface with good hydrophobicity, and the contact angle of a water droplet on the surface can be more than 150°, and the contact angle hysteresis is less than 10°. Due to the good hydrophobicity, the water droplet can quickly roll off the surface after falling on the surface. Therefore, the surface is also used for preventing equipment surfaces from icing in the fields of aviation, navigation, etc. However, to achieve good super-hydrophobicity, microstructures and low surface energy are indispensable. This also makes the super-hydrophobic surface used for anti-icing, and once the surface is damaged, the water droplet will adhere to the super-hydrophobic surface and ice will form. In the process of icing, ice crystals will be embedded in the microstructures of the super-hydrophobic surface, forming a strong combination similar to a mortise and tenon structure, so that the generated ice is very difficult to remove.

[0003] Inspired by the surface of a pitcher plant, scholars have proposed a super-slippery surface with lubricating fluid injection. The super-slippery surface is a surface covered with lubricating fluid prepared by injecting lubricating fluid into the surface of a solid material. The super-slippery surface changes the contact between the solid material and water into the contact between the lubricating fluid and water by means of the lubricating fluid on the surface, thereby greatly reducing the adhesion of water to the solid surface. This makes it easier for water to fall off the material surface after icing, and the lubricating oil film of the super-slippery surface also reduces the thermal conductivity between the solid surface and water, further delaying icing. However, because the water droplet is not easy to fall off the super-slippery surface after falling on it, the surface is more likely to form large-area icing. A large amount of lubricating oil is taken away in the process of ice layer falling off. This greatly reduces the service life of the super-slippery surface.

[0004] It can be seen that the super-hydrophobic surface and the super-slippery surface each have fatal shortcomings in the field of anti-icing and de-icing. In the current research on super-slippery surface anti-icing and de-icing, various biomimetic structure super-hydrophobic coatings and super-hydrophobic anti-icing surfaces are disclosed, which basically solve the problems of poor wear resistance of super-hydrophobic materials and short service life of super-hydrophobic surfaces, but do not mention the ice adhesion problem, which is an important factor directly affecting the de-icing effect. The existing technology also discloses that the durability of the super-slippery surface is enhanced through structural design, but fundamentally speaking, the process of water droplet contact with lubricating fluid and sliding will constantly take away the lubricating fluid. The disclosed technology can only delay failure, but cannot fundamentally solve the problem of lubricating fluid loss leading to failure of the super-slippery surface.

[0005] In summary, in view of the problems that ice is difficult to remove after icing on the super-hydrophobic surface and the lubricating fluid of the super-slippery surface is easy to lose and invalid, an effective solution is urgently needed. SUMMARY

[0006] Technical problems to be solved:

[0007] In order to avoid the shortcomings of the prior art, the present application provides an anti-icing-ice-repellent composite surface and a preparation method, which is coupled with two microstructures of super-hydrophobic / ice-repellent lubricating fluid and hydrophobic / lubricant-philic fluid. By means of the characteristics that the super-hydrophobic / ice-repellent lubricating fluid is not infiltrated by the lubricating fluid, and the hydrophobic / lubricant-philic fluid is completely wrapped by the lubricating fluid, the surface can simultaneously have the anti-icing / ice-repellent performance of super-hydrophobic and super-slippery, that is, it can have excellent anti-icing performance of super-hydrophobic surface, and after icing on the surface, it can be ice-repellent like super-slippery surface, so that the ice is easier to remove. The present application solves the anti-icing technology which cannot be realized by the prior art in practical sense.

[0008] The technical solution of the present application is: an anti-icing-ice-repellent composite surface, comprising a porous material substrate, a super-hydrophobic / ice-repellent lubricating fluid top microstructure coupled to the surface of the substrate, and a hydrophobic / lubricant-philic fluid internal microstructure, wherein the surface of the hydrophobic / lubricant-philic fluid internal microstructure is injected with lubricating fluid.

[0009] The super-hydrophobic / ice-repellent lubricating fluid top microstructure is located on the surface of a plurality of columnar bodies arranged in an array on the porous material substrate, and is a super-hydrophobic / ice-repellent lubricating fluid surface, that is, it has super-hydrophobic characteristics for water and lubricating fluid; the hydrophobic / lubricant-philic fluid internal microstructure is also arranged in an array and surrounds the root of each columnar body, and its surface is a hydrophobic / lubricant-philic fluid surface, that is, it has the characteristics of being lubricant-philic and hydrophobic.

[0010] A further technical solution of the present application is that the particle diameter of the porous material used in the porous material substrate is between 0.1-20 microns.

[0011] A further technical solution of the present application is that the surface of the super-hydrophobic / ice-repellent lubricating fluid top microstructure is a three-level composite microstructure, which is a composite structure of 20-micron-level, 500-nanometer-level and 10-nanometer-level microstructures from bottom to top, which can ensure the characteristics of super-hydrophobic and super-ice-repellent lubricating fluid.

[0012] A further technical solution of the present application is that the columnar body height of the super-hydrophobic / ice-repellent lubricating fluid top microstructure is 30-60 microns, and the size between adjacent columnar bodies is between 1 micron and 500 microns; the characteristic size of the columnar body is between 500 nanometers and 1000 microns.

[0013] A preparation method of an anti-icing-ice-repellent composite surface, the specific steps are as follows:

[0014] Selecting a porous material substrate, and cleaning and drying the surface thereof;

[0015] Preparation of a low surface energy treatment solution;

[0016] Low surface energy treatment of the particles for preparing the multi-level composite microstructure using the low surface energy treatment solution;

[0017] Preparation of the composite microstructure coating for super-hydrophobic and super-oleophobic lubricant using the particles after low surface energy treatment;

[0018] Spraying the composite microstructure coating on the surface of the porous material substrate, coupling the composite nanoscale microstructure in the coating and the microscale microstructure on the surface of the porous substrate, forming a three-level composite microstructure surface with 10 nanometer, 500 nanometer and 20 micrometer, i.e. a super-hydrophobic / oleophobic lubricant top microstructure;

[0019] Generation of the hydrophobic / oleophilic lubricant internal microstructure by removing material from the generation area;

[0020] Low surface energy treatment of the porous material substrate after removing material, generating the hydrophobic / oleophilic lubricant internal microstructure in the area where material is removed;

[0021] Injection of lubricant on the surface of the hydrophobic / oleophilic lubricant internal microstructure, i.e. an ice-prevention-ice-repellent composite surface.

[0022] Further technical solutions of the present application are as follows:

[0023] Adding anhydrous ethanol into a beaker and stirring at room temperature;

[0024] Gradually adding perfluorodecyltriethoxysilane and continuously stirring for 10 minutes to obtain a perfluorodecyltriethoxysilane ethanol low surface energy treatment solution;

[0025] The ratio of perfluorodecyltriethoxysilane to anhydrous ethanol is 2:100.

[0026] Further technical solutions of the present application are as follows:

[0027] Taking 300-500 nanometer diameter silica nanoparticles, 10-50 nanometer diameter silica nanoparticles and carbon nanotubes with a mass ratio of 3.5:2.2:2, slowly adding them into the low surface energy treatment solution respectively, and continuously stirring for 3-5 hours;

[0028] The obtained solution after stirring is filtered by filter paper, and 300-500 nm diameter silica nanoparticles, 10-50 nm diameter silica nanoparticles and carbon nanotubes are filtered out, and surface moisture is dried;

[0029] The surface perfluorodecyl triethoxysilane is completely grafted to the surface of the nanoparticles by continuously drying at a temperature of 120 DEG C for 3 hours, and a mixed powder is obtained.

[0030] A further technical solution of the present application is that the method for preparing the composite microstructure coating of super-hydrophobic and super-oleophobic lubricating fluid is:

[0031] Ethanol is added as a solvent into a beaker and continuously stirred at room temperature;

[0032] The mixed powder after low surface energy treatment is added into the ethanol solution and uniformly stirred;

[0033] The polytetrafluoroethylene emulsion is gradually added and uniformly stirred to obtain a mixed solution;

[0034] The uniformly mixed solution is placed into an ultrasonic tank for ultrasonic treatment for 30 minutes, and a composite microstructure coating with uniformly mixed particles is obtained.

[0035] The mass ratio between the polytetrafluoroethylene emulsion, 300-500 nm diameter silica nanoparticles, 10-50 nm diameter silica nanoparticles, carbon nanotubes and anhydrous ethanol is 3.6:3.5:2.2:2:10.

[0036] A further technical solution of the present application is that the preparation method of the top microstructure of the super-hydrophobic / oleophobic lubricating fluid is:

[0037] The composite microstructure coating is sprayed on the surface of a porous material substrate with a thickness less than 20 microns;

[0038] The porous material substrate after spraying the coating is placed into an oven, the temperature is set for 3 hours, and the temperature is increased from room temperature to 350 DEG C, maintained at 350 DEG C for 10 minutes, and then slowly decreased to room temperature;

[0039] The composite nanoscale microstructure in the coating and the micrometer-scale microstructure of the porous substrate surface are coupled to form a three-level composite microstructure surface with 10 nm, 500 nm and 20 microns, which can ensure the characteristics of the super-hydrophobic and super-oleophobic lubricating fluid.

[0040] A further technical solution of the present application is that the preparation method of the internal microstructure of the hydrophobic / oleophilic lubricating fluid is:

[0041] The porous material substrate with a composite microstructure surface is subjected to material removal processing, wherein the recessed part after material removal is a generation area of the hydrophobic / oleophilic fluid internal microstructure, and the part without material removal is a plurality of columnar bodies with superhydrophobic / oleophobic fluid top microstructure and arranged in a periodic array;

[0042] The surface of the porous material substrate after material removal is subjected to low surface energy treatment; first, perfluorodecyltriethoxysilane is dropped into a culture dish, and the surface of the porous material substrate after material removal is placed in the culture dish; then, the culture dish is placed in an oven and heated to 80 degrees Celsius, and then quickly taken out and placed in a vacuum tank for vacuum treatment for 1 hour; then, it is taken out and continuously heated in the oven at 120 degrees Celsius for 3 hours, and then taken out, thereby obtaining the hydrophobic / oleophilic fluid internal microstructure.

[0043] Advantages

[0044] The present application has the advantages that the present application couples the superhydrophobic / oleophobic fluid microstructure and the hydrophobic / oleophilic fluid microstructure, so that the porous material substrate surface has the characteristics of the superhydrophobic / oleophobic fluid microstructure and the hydrophobic / oleophilic fluid microstructure, thereby enabling the superhydrophobic surface to have the ice prevention characteristic, and even if the surface is iced, the ice can be easily removed. The surface structure of the present application can greatly promote the progress of modern ice prevention surface technology. The specific advantages are as follows:

[0045] 1. The present application creatively proposes an ice prevention-ice prevention composite surface combining superhydrophobic surface and super slippery surface, which has excellent superhydrophobic properties (average contact angle greater than 150°) and can greatly reduce the adhesion of ice (so that the ice adhesion can be reduced to below 85 kPa) after icing.

[0046] 2. The superhydrophobic layer of the top layer of the surface can play a superhydrophobic role. When the surface encounters water droplets, the superhydrophobic property can make the water droplets bounce away quickly without adhering to the surface, preventing large-area icing. At the same time, since the water droplets are quickly bounced away and do not come into contact with the lubricating fluid inside the microstructure, the lubricating fluid loss caused by the water droplets carrying away the lubricating fluid is also avoided. Unlike superhydrophobic, when the surface is subjected to long-term and multiple flushing, the superhydrophobic surface defects cause the hydrophobicity to weaken, resulting in water droplets adhering and icing, or when water vapor sublimates on the surface, the lubricating fluid in the superhydrophobic structure groove hinders the embedding of ice crystals into the superhydrophobic structure, preventing the formation of mechanical interlocking between the microstructure and the surface microstructure, thereby greatly reducing the adhesion of ice. With the increase of ice accumulation, the ice will also fall off the surface under the action of its own gravity. In addition, since the lubricating fluid is inside the superhydrophobic surface groove, the lubricating fluid is less likely to be lost, thereby greatly increasing the effective service life of the surface.

[0047] 3. The preparation method of the present application specifically defines the raw materials and particle sizes for preparing the super-hydrophobic / oleophobic fluid top microstructure which is both super-hydrophobic and super-oleophobic, wherein the mass ratio between the polytetrafluoroethylene emulsion, 300-500 nanometer diameter silica nanoparticles, 10-50 nanometer diameter silica nanoparticles, carbon nanotubes, and anhydrous ethanol is 3.6:3.5:2.2:2:10. Under this mass ratio, the number of particles of each size is moderate, the gravity and surface tension are balanced, the small-size nanoscale silica particles, carbon nanotubes, and polytetrafluoroethylene particles can be attached to the surface of the large-size particles, the large-size particle surface is completely covered by small-size particles without forming a large-area accumulation, and finally a three-level composite microstructure surface with 10 nanometer, 500 nanometer, and 20 micrometer levels is formed, which is more uniform, has more distinct structure levels, and has a larger surface area. After low-surface-energy treatment, the complex three-level microstructure can more stably bind air in the microstructure cavities, thereby preventing the lubricating fluid and water from entering the microstructure, and further achieving better super-oleophobic fluid properties while ensuring super-hydrophobicity.

[0048] The surface ice-prevention and ice-repellent performance mentioned in the present application is strong, the processing method has strong applicability, can be used for large-area processing on the surface of different metal materials or polymer materials, and is expected to solve the ice-prevention and ice-repellent engineering problems. BRIEF DESCRIPTION OF DRAWINGS

[0049] Figure 1 FIG. 1 is a structural diagram of an ice-prevention and ice-repellent composite surface according to an embodiment of the present application;

[0050] Figure 2 FIG. 5 is a top view of a square columnar microstructure according to an embodiment of the present application;

[0051] Figure 3 FIG. 7 is a top view of a cylindrical microstructure according to an embodiment of the present application;

[0052] Figure 4 FIG. 11 is a macroscopic large-scale sample diagram of microstructure processing according to an embodiment of the present application;

[0053] Figure 5 FIG. 13 is a microscopic enlarged sample diagram of microstructure according to an embodiment of the present application;

[0054] Figure 6 FIG. 15 is a super-hydrophobic measurement diagram of the microstructure surface according to an embodiment of the present application;

[0055] Figure 7 FIG. 17 is an ice adhesion test result diagram according to an embodiment of the present application;

[0056] Figure 8 FIG. 19 is a surface and contact angle (a) and adhesion test result (b) according to an embodiment 1 of the present application;

[0057] Figure 9 Table 1 Surface and contact angle (b) Adhesion test results for Example 2 of the present application (a);

[0058] Legend: 1. Porous material substrate, 2. Superhydrophobic / omniphobic lubricant top microstructure, 3. Hydrophobic / omniphilic lubricant inner microstructure, 4. Lubricant. DETAILED DESCRIPTION

[0059] The examples described below by reference to the accompanying drawings are exemplary and are intended to serve to explain the present application and cannot be understood as a limitation of the present application.

[0060] Based on the problems that the prior art superhydrophobic surface is difficult to remove after icing and the super-slippery surface lubricant is easy to lose and fail, the present application provides an anti-icing-ice-repellent composite surface, referring to Figure 1 , which comprises a porous material substrate 1, a superhydrophobic / omniphobic lubricant top microstructure 2, a hydrophobic / omniphilic lubricant inner microstructure 3 and a lubricant 4; the superhydrophobic / omniphobic lubricant top microstructure 2 is located on the surface of a plurality of columnar bodies arranged in an array on the porous material substrate 1, and is a superhydrophobic / omniphobic lubricant surface, i.e. has superhydrophobic properties to water and lubricant; the hydrophobic / omniphilic lubricant inner microstructure 3 is also arranged in an array and surrounds the root of each columnar body, and its surface is a hydrophobic / omniphilic lubricant surface, i.e. has omniphilic lubricant and hydrophobic properties.

[0061] , referring to Figure 2 and Figure 3 , the porous material substrate 1 is a carrier for all microstructure processing; the superhydrophobic / omniphobic lubricant top microstructure 2 is the outermost microstructure after etching and contacting with water droplets and ice, and has superhydrophobic properties to water and lubricant, so that water droplets and super-slippery fluid cannot wet the surface thereof; the hydrophobic / omniphilic lubricant inner microstructure 3 is a concave structure etched on the surface of the porous material substrate 1, and the surface thereof has omniphilic lubricant and hydrophobic properties, can be wetted by lubricant (the contact angle of lubricant on the surface thereof is less than 90°) but cannot be wetted by water droplets (the contact angle of water droplets on the surface thereof is greater than 90°); the lubricant 4 is inside the hydrophobic / omniphilic lubricant microstructure 3 and does not wet the superhydrophobic / omniphobic lubricant top microstructure 2; it should be noted that the porous material substrate 1 can be selected from different materials according to different use scenarios, and the particle diameter of the porous material is between 0.1-20 microns; the icing temperature of the lubricant 4 should be lower than the minimum temperature of the used environment (generally, the icing temperature of the lubricant should be lower than -20℃).

[0062] The anti-icing / ice-phobic principle of the anti-icing-ice-phobic composite surface: the super-hydrophobic layer on the top layer of the surface can play a super-hydrophobic role. When the surface encounters water droplets, the super-hydrophobic property can make the water droplets quickly bounce off and not adhere to the surface, preventing large-area icing. At the same time, since the water droplets are quickly bounced off and do not come into contact with the lubricating fluid inside the microstructure, the loss of lubricating fluid caused by the water droplets carrying away the lubricating fluid is also avoided. Unlike super-hydrophobic, when the surface is washed for a long time and many times, the super-hydrophobic surface defects cause the hydrophobicity to weaken, causing water droplets to adhere and accumulate to ice, or when encountering water vapor subliming on the surface to form ice, the lubricating fluid in the super-hydrophobic structure groove will hinder the embedding of ice crystals into the super-hydrophobic structure, preventing the mechanical interlocking between the microstructure and the surface microstructure, thereby greatly reducing the adhesion of ice. With the increase of accumulated ice, the accumulated ice will also fall off from the surface under the action of its own gravity. In addition, since the lubricating fluid is inside the super-hydrophobic surface groove, the lubricating fluid is also less likely to be lost, thereby greatly increasing the effective service life of the surface.

[0063] The application discloses a preparation method of an anti-icing-ice-phobic composite surface with super-hydrophobic-super-slippery properties, and specific steps are as follows:

[0064] Step one: preparing a material substrate: take a porous material substrate of appropriate size, first ultrasonic clean with acetone for 30 minutes, take out and then ultrasonic clean with anhydrous ethanol for 30 minutes, finally ultrasonic clean with deionized water for 30 minutes, and then place in a high-temperature drying oven at 120 degrees Celsius for drying for 2 hours for standby, to obtain a substrate surface free of impurities.

[0065] Step two: selecting raw materials for preparing super-hydrophobic / ice-phobic lubricating fluid top microstructure 2 which can be ice-phobic and lubricating fluid-phobic: take silica nanoparticles with a diameter of 10-50 nanometers and silica nanoparticles with a diameter of 300-500 nanometers, polytetrafluoroethylene emulsion (mass fraction 60%), perfluorodecyltriethoxysilane, carbon nanotubes and anhydrous ethanol for standby;

[0066] Step three: preparing a low surface energy treatment solution: take perfluorodecyltriethoxysilane and anhydrous ethanol with a volume ratio of 2:100, first add anhydrous ethanol into a beaker, place the beaker on a magnetic stirrer and start stirring at room temperature, then gradually add perfluorodecyltriethoxysilane and continue stirring for 10 minutes, to obtain a perfluorodecyltriethoxysilane ethanol low surface energy treatment solution.

[0067] Step four: low surface energy treatment of the particles: take 300-500 nanometer diameter silica nanoparticles, 10-50 nanometer diameter silica nanoparticles and carbon nanotubes with a mass ratio of 3.5:2.2:2, slowly add to the solution prepared in step three respectively, and continuously stir for 3-5 hours; wherein the carbon nanotubes, 10-50 nanometer diameter silica nanoparticles and 300-500 nanometer diameter silica nanoparticles are used to form a composite microstructure with a multi-level structure. It should be noted that the beaker opening is covered with plastic wrap during stirring to prevent the evaporation of liquid components.

[0068] Step five: filter out the 300-500 nanometer diameter silica nanoparticles, 10-50 nanometer diameter silica nanoparticles and carbon nanotubes in the beaker of step four through filter paper, and then put the filtered mixed powder into an oven; first use 80°C to dry for 3 hours, slowly dry the surface of the anhydrous ethanol, and then use a temperature of 120°C to dry for 3 hours, so that the perfluorodecyltriethoxysilane on the surface is completely grafted to the surface of the nanoparticles, i.e. the mixed powder is obtained.

[0069] Step six: preparation of a composite microstructure coating that can both repel lubricating fluid and water: take the above dried powder for standby, and take polytetrafluoroethylene emulsion and anhydrous ethanol, so that the mass ratio between the polytetrafluoroethylene emulsion, 300-500 nanometer diameter silica nanoparticles, 10-50 nanometer diameter silica nanoparticles, carbon nanotubes and anhydrous ethanol reaches 3.6:3.5:2.2:2:10.

[0070] First, add ethanol as a solvent into a beaker and continuously stir using a magnetic stirrer, then add the mixed powder prepared in step five into the ethanol solution, cover the beaker with plastic wrap, and stir at room temperature for 3-5 hours until it is evenly stirred. Then gradually add the polytetrafluoroethylene emulsion into the aforementioned uniform solution, continue to stir at room temperature for 3-5 hours until it is evenly stirred. Finally, put the uniformly mixed solution into an ultrasonic tank for ultrasonic treatment for 30 minutes to ensure that the particles are mixed more uniformly, i.e. a composite microstructure coating with uniformly mixed particles is obtained.

[0071] It has been verified that this ratio can ensure that small-sized nanoscale silica particles, carbon nanotubes and polytetrafluoroethylene particles are attached to the surface of large-sized particles to form a multi-level composite microstructure.

[0072] Step seven: spray the coating on the surface of the substrate to form a coating: use the solution prepared in step six to spray on the surface of the porous material substrate prepared in step one by spraying, and the spraying thickness should be less than 20 microns.

[0073] Step eight: drying the coating and enhancing the adhesion of the coating: the surface of the substrate after spraying the coating is placed in an oven, and the temperature is set to increase from room temperature to 350 degrees Celsius for 3 hours, maintained at 350 degrees Celsius for 10 minutes, and then slowly cooled to room temperature; the temperature will cause the polytetrafluoroethylene particles in the polytetrafluoroethylene emulsion to begin to melt into a fluid state, thereby firmly bonding the above-mentioned nanoparticles and the substrate surface together, and the heating lasts for 10 minutes to ensure that the polytetrafluoroethylene particles do not flow into the porous microstructure substrate after melting. At this time, the composite nanoscale microstructure in the coating and the micrometer-scale microstructure of the porous substrate surface are coupled to form a three-level composite microstructure surface with 10 nanometer, 500 nanometer and 20 micrometer levels, which can guarantee the properties of superhydrophobicity and superlubricant.

[0074] Step nine: preparing the hydrophobic / lubricant-wettable internal microstructure 3: the prepared surface is taken out of the oven, and a material removal processing method (such as laser processing, mechanical processing, etc.) is used to process a microstructure as shown in Figure 2 on the surface of the substrate material (the microstructure in the figure is a square, and it can also be processed into a circle, an ellipse, a polygon or other shapes), wherein the shaded part is the material removal part, and the material removal thickness is about 30-60 micrometers (completely removing the coating prepared in steps seven and eight from the substrate surface). The inter-column distance L1 and L2 are between 1 micrometer and 500 micrometers, and the column feature size L is between 500 nanometers and 1000 micrometers.

[0075] Step ten: low surface energy treatment of the substrate surface: 5 microliters of perfluorodecyltriethoxysilane is dropped into a culture dish, the surface processed in step nine is placed in the culture dish, and then the culture dish is placed in an oven and heated to 80 degrees Celsius. It is quickly taken out and placed in a vacuum tank for vacuum treatment for 1 hour, and then it is taken out and continued to be placed in an oven at 120 degrees Celsius for 3 hours. After heating, it is taken out.

[0076] Step eleven: filling with lubricant 4: the surface processed in step ten is taken out and soaked in a lubricant for 5 minutes, and then taken out, at which time the surface microstructure as shown in Figure 1 is obtained.

[0077] The above technical solutions are further described in conjunction with examples as follows:

[0078] Example one:

[0079] This embodiment is a titanium plate porous material-based anti-ice-ice-repellent composite surface and a preparation method, and the specific steps are as follows:

[0080] Step one: prepare a 40cm*40cm titanium plate porous material substrate, first use acetone ultrasonic cleaning for 30 minutes, take out and then use anhydrous ethanol ultrasonic cleaning for 30 minutes, finally use deionized water ultrasonic cleaning for 30 minutes, and then put it into a high temperature drying oven at 120 degrees Celsius for 2 hours for standby.

[0081] Step two: take 50 nanometer diameter and 500 nanometer diameter silica nanoparticles, polytetrafluoroethylene emulsion (mass fraction 60%), perfluorodecyl triethoxysilane, carbon nanotube and anhydrous ethanol for standby.

[0082] Step three: take 1 milliliter of perfluorodecyl triethoxysilane and 100 milliliters of anhydrous ethanol, first add anhydrous ethanol into beaker, put the beaker on the magnetic stirrer and start stirring at room temperature, then gradually add perfluorodecyl triethoxysilane and continue stirring for 10 minutes.

[0083] Step four: take 56 grams of 500 nanometer diameter silica nanoparticles, 35.2 grams of 50 nanometer diameter silica nanoparticles and 32 grams of carbon nanotube respectively, slowly add them into the solution prepared in step three respectively, and continue stirring for 3-5 hours; it should be noted that the beaker opening should be covered with plastic wrap during stirring to prevent the evaporation of liquid components.

[0084] Step five: filter out the nanodiameter silica nanoparticles and carbon nanotubes in the beaker of step four through filter paper, then put the filtered mixed powder into an oven and dry it at 80℃ and 120℃ respectively for 3 hours until it is completely dry.

[0085] Step six: take out the above dried powder for standby, and take 57.6 grams of polytetrafluoroethylene emulsion and 160 grams of anhydrous ethanol, first add ethanol into beaker, use magnetic stirrer to stir constantly, then add the mixed powder prepared in step five into the ethanol solution, cover the beaker with plastic wrap, stir at room temperature for 3-5 hours until it is evenly stirred. Then gradually add polytetrafluoroethylene emulsion into the above uniform solution, continue to stir at room temperature for 3-5 hours until it is evenly stirred. Finally, put the uniform mixed solution into an ultrasonic tank for ultrasonic treatment for 30 minutes.

[0086] Step seven: use spraying method to spray the solution prepared in step six on the surface of the porous material substrate prepared in step one, and the spraying thickness should be less than 20 microns.

[0087] Step eight: put the substrate surface after spraying coating into the oven, set the temperature to increase from room temperature to 350 degrees Celsius for 3 hours, maintain at 350 degrees Celsius for 10 minutes, then slowly cool it to room temperature.

[0088] Step nine: the prepared surface is taken out of the oven, and laser etching is used to process a square microstructure as shown in Figure 2 , where the shaded part is the removed material part, and the removed material thickness is 30 microns. The inter-column distance L1 and L2 size is 100 microns, and the column feature size L is 100 microns.

[0089] Step ten: 5 microliters of perfluorodecyltriethoxysilane is dropped into a culture dish, and the surface processed in step nine is placed in the culture dish, and then the culture dish is placed in an oven and heated to 80 degrees Celsius. It is quickly taken out and placed in a vacuum tank for vacuum treatment for 1 hour, and then it is taken out and continued to be heated in an oven at 120 degrees Celsius for 3 hours. After heating, it is taken out.

[0090] Step eleven: the surface processed in step ten is taken out and soaked in a lubricating fluid with a viscosity of 50 mPa.s for 5 minutes, and then taken out. At this time, an ice-repellent and ice-repellent microstructure surface is obtained.

[0091] The processed microstructure surface is as shown in Figure 8 . The surface has excellent super-hydrophobic properties, and the ice adhesion force can be maintained below 80 KPa in multiple measurements.

[0092] Example two

[0093] This embodiment is an aluminum-based ice-repellent and ice-repellent composite surface with super-hydrophobic and super-slippery properties and a preparation method. The specific steps are as follows:

[0094] Step one: prepare a 40 cm*40 cm aluminum-based porous material substrate. First, ultrasonic cleaning with acetone for 30 minutes, then ultrasonic cleaning with anhydrous ethanol for 30 minutes, and finally ultrasonic cleaning with deionized water for 30 minutes. Then, place it in a high-temperature drying oven at 120 degrees Celsius for 2 hours for standby.

[0095] Step two: take 50 nanometer diameter and 500 nanometer diameter silica nanoparticles, polytetrafluoroethylene emulsion (60% mass fraction), perfluorodecyltriethoxysilane, carbon nanotubes, and anhydrous ethanol for standby.

[0096] Step three: take 1 milliliter of perfluorodecyltriethoxysilane and 100 milliliters of anhydrous ethanol. First, add anhydrous ethanol to a beaker, place the beaker on a magnetic stirrer, and start stirring at room temperature. Then gradually add perfluorodecyltriethoxysilane and continue stirring for 10 minutes.

[0097] Step four: Take 56 grams of 500 nanometer diameter silica nanoparticles, 35.2 grams of 50 nanometer diameter silica nanoparticles and 32 grams of carbon nanotubes respectively, slowly add them into the solution prepared in step three, and continue stirring for 3-5 hours; it should be noted that during the stirring process, the beaker opening should be covered with plastic wrap to prevent the evaporation of liquid components.

[0098] Step five: Filter out the nanometer diameter silica nanoparticles and carbon nanotubes in the beaker of step four through filter paper, then put the filtered mixed powder into an oven and dry it at 80°C and 120°C respectively for 3 hours until it is completely dry.

[0099] Step six: Take out the above dried powder for standby, and take 57.6 grams of polytetrafluoroethylene emulsion and 160 grams of anhydrous ethanol, first add ethanol into the beaker, continuously stir with a magnetic stirrer, then add the mixed powder prepared in step five into the ethanol solution, cover the beaker with plastic wrap, and stir at room temperature for 3-5 hours until it is evenly stirred. Then gradually add the polytetrafluoroethylene emulsion into the above uniform solution, continue to stir at room temperature for 3-5 hours until it is evenly stirred. Finally, put the uniformly mixed solution into an ultrasonic tank for ultrasonic treatment for 30 minutes.

[0100] Step seven: The solution prepared in step six is sprayed on the surface of the porous material substrate prepared in step one by spraying, and the spraying thickness should be less than 20 microns.

[0101] Step eight: Put the substrate surface after spraying into an oven, set the temperature to increase from room temperature to 350°C in 3 hours, maintain at 350°C for 10 minutes, and then slowly cool it to room temperature.

[0102] Step nine: Take out the prepared surface from the oven, and use laser etching method to process circular microstructure on the surface of the substrate material as shown in Figure 3 , where the shaded part is the removed material part, and the removed material thickness is 40 microns. The column interval L1 and L2 size is 100 microns, and the column feature size L is 100 microns.

[0103] Step ten: Take 5 microliters of perfluorodecyltriethoxysilane and drop it into a culture dish, then put the surface processed in step nine into the culture dish, and then put the culture dish into an oven and heat it to 80°C. Take it out and put it into a vacuum tank for vacuum treatment for 1 hour, then take it out and continue to heat it in the oven at 120°C for 3 hours. After heating, take it out.

[0104] Step eleven: Take out the surface processed in step ten and soak it in a lubricating fluid with a viscosity of 50 mPa.s for 5 minutes, then take it out, and you can get the ice and icephobic microstructure surface.

[0105] The processed microstructure surface has excellent super-hydrophobic properties, and the ice adhesion force is also maintained below 80 KPa in multiple measurements. Figure 9 The processed microstructure surface has excellent super-hydrophobic properties, and the ice adhesion force is also maintained below 80 KPa in multiple measurements.

[0106] It should be noted that: (1) the examples provided in the present application are the expansion and extension of the idea of the present application, and are not used to limit the content of the present application; (2) all the surfaces that realize the idea provided by the present application, no matter how they are prepared, i.e. the part of the groove top directly contacting water or ice (or the microstructure protruding part, the top microstructure part) has the dual-scarcity property of being oil-repellent and water-repellent, the inside of the groove (the microstructure recessed part, the bottom microstructure part, or the remaining part other than the top microstructure) has the property of being lubricant-wettable and water-repellent, and the surface in which the lubricant is injected into the inside of the groove while the groove top still has the dual-scarcity property, all fall within the protection scope of the present application.

[0107] Although the embodiments of the present application have been shown and described above, it should be understood that the above-mentioned embodiments are exemplary and should not be construed as limiting the present application, and those of ordinary skill in the art can make changes, modifications, replacements and variations to the above-mentioned embodiments without departing from the principles and purposes of the present application within the scope of the present application.

Claims

1. A method for preparing an anti-icing-repellent composite surface, characterized in that: The anti-icing-repellent composite surface comprises a porous material substrate and a superhydrophobic / lubricant-repellent top microstructure and a hydrophobic / lubricant-affinity internal microstructure coupled to its surface. The surface of the hydrophobic / lubricant-affinity internal microstructure is filled with lubricating fluid. The superhydrophobic / lubricant-repellent top microstructure is located on the surface of several columnar bodies arranged in an array on the porous material substrate, and is a superhydrophobic / lubricant-repellent surface, i.e., it has superhydrophobic properties to both water and lubricating fluid. The hydrophobic / lubricant-affinity internal microstructure is also arranged in an array and surrounds the root of each columnar body, and its surface is a hydrophobic / lubricant-affinity surface, i.e., it has both lubricant-affinity and hydrophobic properties. The specific steps of the preparation method are as follows: Select a porous material substrate and clean and dry its surface; Preparation of low surface energy treatment solutions; The particles used to prepare the multi-level composite microstructure were subjected to low surface energy treatment using a low surface energy treatment solution. Specifically, 300-500 nm diameter silica nanoparticles, 10-50 nm diameter silica nanoparticles, and carbon nanotubes in a mass ratio of 3.5:2.2:2 were slowly added to the low surface energy treatment solution and stirred continuously for 3-5 hours. The resulting solution was filtered through filter paper to remove the 300-500 nm diameter silica nanoparticles, 10-50 nm diameter silica nanoparticles, and carbon nanotubes, and the surface moisture was dried. The solution was then dried at 120°C for 3 hours to ensure complete grafting of perfluorodecyltriethoxysilane onto the nanoparticle surface, resulting in a mixed powder. A composite microstructure coating for superhydrophobic and superlubricating fluids was prepared using particles treated with low surface energy. The specific method involved: adding ethanol as a solvent to a beaker and continuously stirring at room temperature; adding the mixed powder treated with low surface energy to the ethanol solution and stirring until homogeneous; gradually adding polytetrafluoroethylene (PTFE) emulsion and stirring until homogeneous to obtain a mixed solution; and ultrasonically treating the homogeneous mixed solution in an ultrasonic bath for 30 minutes to obtain a composite microstructure coating with uniformly mixed particles. The mass ratio of PTFE emulsion, 300-500 nm diameter silica nanoparticles, 10-50 nm diameter silica nanoparticles, carbon nanotubes, and anhydrous ethanol was 3.6:3.5:2.2:2:

10. The composite microstructure coating is sprayed onto the surface of a porous material substrate. The composite nanoscale microstructure in the coating is coupled with the micron-scale microstructure on the porous substrate surface, forming a three-level composite microstructure surface with 10 nanometer, 500 nanometer, and 20 micrometer scales, thus obtaining a superhydrophobic / superlubricant-repellent fluid top microstructure. Specifically, the composite microstructure coating is sprayed onto the surface of the porous material substrate with a thickness of less than 20 micrometers. The coated porous material substrate surface is placed in an oven, and the temperature is set for 3 hours, increasing from room temperature to 350 degrees Celsius, maintaining at 350 degrees Celsius for 10 minutes, and then slowly decreasing to room temperature. The composite nanoscale microstructure in the coating is coupled with the micron-scale microstructure on the porous substrate surface, forming a three-level composite microstructure surface with 10 nanometer, 500 nanometer, and 20 micrometer scales, ensuring the superhydrophobic and superlubricant-repellent fluid properties. The generation region of the internal microstructure of hydrophobic / lubricating fluids is prepared by material removal; Low surface energy treatment is applied to the porous material substrate after material removal to generate hydrophobic / lubricating fluid internal microstructures in the material removal area; By injecting lubricating fluid into the surface of the microstructure inside the hydrophobic / lubricating fluid, an anti-icing-repellent composite surface is obtained.

2. The method for preparing an anti-icing-repellent composite surface according to claim 1, characterized in that: The porous material used in the porous material substrate has a particle diameter between 0.1 and 20 micrometers.

3. The method for preparing an anti-icing-repellent composite surface according to claim 1, characterized in that: The surface of the top microstructure of the superhydrophobic / lubricant-repellent fluid is a three-level composite microstructure, consisting of 20-micrometer, 500-nanometer, and 10-nanometer microstructures from bottom to top, which can ensure the properties of superhydrophobic and superlubricant fluids.

4. The method for preparing an anti-icing-repellent composite surface according to claim 1, characterized in that: The columnar structure at the top of the superhydrophobic / lubricant-repellent fluid has a height of 30-60 micrometers, and the size between adjacent columns is between 1 micrometer and 500 micrometers; the characteristic size of the column is between 500 nanometers and 1000 micrometers.

5. The method for preparing an anti-icing-repellent composite surface according to claim 1, characterized in that: The preparation method of the low surface energy treatment solution is as follows: Add anhydrous ethanol to a beaker and stir at room temperature; Perfluorodecyltriethoxysilane was gradually added and stirred for 10 minutes to obtain a perfluorodecyltriethoxysilane ethanol low surface energy treatment solution. The product ratio of perfluorodecyltriethoxysilane to anhydrous ethanol is 2:

100.

6. The method for preparing an anti-icing-repellent composite surface according to claim 1, characterized in that: The method for preparing the internal microstructure of the hydrophobic / lubricating fluid is as follows: A porous material substrate with a composite microstructure surface is subjected to material removal processing. The recessed part after material removal is the generation region of the internal microstructure of hydrophobic / lubricating fluid, while the part without material removal is a number of columnar bodies with superhydrophobic / lubricating fluid top microstructures, arranged in a periodic array. The porous material substrate surface after material removal is subjected to low surface energy treatment. First, perfluorodecyltriethoxysilane is dropped into a petri dish, and the porous material substrate surface after material removal is placed into the petri dish at the same time. Then, the petri dish is placed in an oven and heated to 80 degrees Celsius. After that, it is quickly removed and placed in a vacuum autoclave for vacuum treatment for 1 hour. Then, it is removed and placed in an oven for heating at 120 degrees Celsius for 3 hours. After heating is completed, it is removed to obtain the hydrophobic / lubricating fluid internal microstructure.

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