An anti-icing coating for polar ships with adjustable ice adhesion and its preparation method

Abstract

An anti-icing coating for polar ships with adjustable ice adhesion and its preparation method, belonging to the field of anti-icing on the ship surface; it includes a double-layer coupling structure composed of a primer and a topcoat, and the coverage area of the topcoat on the primer is in a dynamically controllable form; the primer is a super-slippery surface, and its surface microstructure prevents ice crystals from embedding into the interior of the microstructure by locking lubricating oil; the topcoat is a super-hydrophobic surface obtained by directionally screening and removing magnetic particles in the topcoat paint, and the micro-region distribution of the super-hydrophobic surface is complementary to the spatial arrangement of the removed magnetic particles. By controlling the spatial distribution of the magnetic particles, the exposed area of the super-slippery surface primer is regulated. The present invention solves the problem of the contradiction that a single coating cannot take into account both "anti-icing" and "low adhesion".

Description

Technical Field

[0001] The present invention belongs to the field of anti-icing on the surface of ships, and particularly relates to an anti-icing coating for polar ships with adjustable ice adhesion and a preparation method thereof. Background Art

[0002] The icing phenomenon is very common in life, but ship icing will seriously affect the navigation safety of ships. Under icing climate conditions, seawater splashing and scouring the hull, and supercooled water droplets in the atmosphere condensing on the ship surface are extremely likely to cause icing on the ship surface. Icing will not only seriously affect the basic functions of polar ships, but also increase the draft depth and center of gravity of the ships, affecting the ship stability. In addition, the icing of seawater containing salts on radio communication equipment and radars will change their dielectric constants, affecting signal transmission and reception. Therefore, how to effectively prevent polar ships from icing is one of the important technical challenges faced by polar ships at present.

[0003] At present, ship anti-icing technologies can be divided into two types: anti-icing with superhydrophobic coatings and anti-icing with super-slippery coatings. The specific problems are as follows: Although the superhydrophobic surface can delay surface icing, when the superhydrophobic surface is iced, ice crystals will embed into the microstructures of the superhydrophobic surface, greatly increasing the ice adhesion force; The super-slippery surface can greatly reduce the ice adhesion force, but it cannot prevent icing, and the oil film on its surface will quickly lose under the long-term scouring of rainwater and sea waves, losing the super-slippery effect.

[0004] It can be seen that the current anti-icing coatings cannot solve the problems of delaying icing and reducing ice adhesion force at the same time, and cannot achieve the regulation of ice adhesion force. Therefore, there is an urgent need to invent a coating with simple preparation, strong applicability, which can delay icing and reduce ice adhesion force after icing. Summary of the Invention

[0005] Technical Problems to be Solved

[0006] In order to avoid the deficiencies of the prior art, the present invention provides an anti-icing coating for polar ships with adjustable ice adhesion and a preparation method thereof. The anti-icing coating couples a topcoat with superhydrophobic performance and a primer with super-slippery performance. The superhydrophobic topcoat delays icing, and the super-slippery primer reduces the ice adhesion force, solving the contradiction problem that a single coating cannot take into account both "anti-icing" and "low adhesion"; At the same time, by using the coating reaction of iron powder particles and ammonium carbonate, combined with the electromagnetic field directional adsorption technology, the particle distribution in the topcoat is accurately controlled to ensure the coating uniformity, and the dynamic regulation of the exposed area of the super-slippery primer is ensured, which can be applicable to different environmental requirements.

[0007] The technical solution of the present invention is: an anti-icing coating for polar ships with adjustable ice adhesion, including a double-layer coupling structure composed of a primer and a topcoat, and the coverage area of the topcoat on the primer is in a dynamically controllable form;

[0008] The primer has a super-slippery surface, and its surface microstructure prevents ice crystals from embedding into the interior of the microstructure by locking lubricating oil.

[0009] The topcoat is a super-hydrophobic surface obtained by directionally screening and removing magnetic particles in the topcoat paint. The micro-region distribution of the super-hydrophobic surface is complementary to the spatial arrangement of the removed magnetic particles, and the exposed area of the super-slippery surface primer is regulated by controlling the spatial distribution of the magnetic particles.

[0010] A further technical solution of the present invention is that the primer is a super-slippery layer formed by spraying primer paint on the surface of the substrate and filling the microstructure with lubricating oil. The primer paint is composed of polydimethylsiloxane, dichloromethane, dimethyl silicone oil, and silane coupling agent.

[0011] A further technical solution of the present invention is that the topcoat is a super-hydrophobic surface formed by heating the topcoat paint sprayed on the surface of the primer, covering part of the primer, and exposing part of the primer; the topcoat paint is composed of super-hydrophobic particles, iron powder particles wrapped with ammonium carbonate crystals, and ethanol.

[0012] A further technical solution of the present invention is that the spraying thickness of the primer paint is 20 microns, and the spraying thickness of the topcoat paint is 10 microns.

[0013] A further technical solution of the present invention is the method for adjusting the coverage area of the topcoat on the primer:

[0014] Determine the super-hydrophobic particles in the topcoat paint as 10-micron porous silica particles;

[0015] Set the exposed area ratio of the primer as required, and calculate the diameter of the iron powder particles by using the following formula:

[0016]

[0017] Wherein, is the exposed area ratio of the primer, is the diameter of the porous silica particles, is the diameter of the iron powder particles;

[0018] According to the density ratio of the porous silica particles and the iron powder particles, calculate the mass ratio of the porous silica particles and the iron powder particles, and prepare the topcoat paint according to the obtained mass ratio, then an anti-icing coating that can control the coverage area of the topcoat on the primer as required can be obtained.

[0019] A preparation method of an anti-icing coating for polar ships with adjustable ice adhesion force is as follows:

[0020] Preparation of topcoat paint: Superhydrophobic particles, iron powder particles wrapped with ammonium carbonate crystals, and ethanol are mixed and stirred at room temperature, and then subjected to ultrasonic dispersion treatment to obtain the topcoat paint; among them, the superhydrophobic particles and the iron powder particles wrapped with ammonium carbonate crystals are used as solute particles, and ethanol is used as a solvent, and the mass ratio of the solute particles to the solvent is 2:5;

[0021] Preparation of primer paint: Polydimethylsiloxane, dichloromethane, and dimethyl silicone oil are mixed and stirred at room temperature, and then subjected to ultrasonic dispersion treatment to obtain a paint precursor solution. The paint precursor solution is mixed and stirred evenly with a silane coupling agent to obtain the primer paint;

[0022] The primer paint is sprayed on the surface of the substrate and dried at 60 °C for 15 minutes to obtain a semi-cured primer;

[0023] The topcoat paint is sprayed on the surface of the semi-cured primer, heated and cured, and then cooled to room temperature; during the heating process, the ammonium carbonate crystals coated on the surface of the iron powder particles volatilize, exposing the iron powder particles;

[0024] The exposed iron powder particles are removed by an electromagnet, so that the primer at the position where the iron powder particles are located is exposed, and an anti-icing coating with a double-layer coupling of primer and topcoat is obtained.

[0025] A further technical solution of the present invention is: The specific steps for preparing the topcoat paint are as follows:

[0026] Etch the surface of the porous silica particles with a sodium hydroxide solution to form silica particles with a nanoscale micro-surface structure;

[0027] Perform low surface energy treatment on the silica particles with the nanoscale micro-surface structure to obtain silica nanoparticles with dual hydrophobic properties, that is, superhydrophobic particles;

[0028] Prepare iron powder particles wrapped with ammonium carbonate crystals;

[0029] The silica nanoparticles with dual hydrophobic properties, the iron powder particles wrapped with ammonium carbonate crystals, and ethanol are mixed and stirred at room temperature, and then subjected to ultrasonic dispersion treatment at room temperature to obtain the topcoat paint.

[0030] A further technical solution of the present invention is: The preparation method of the iron powder particles wrapped with ammonium carbonate crystals is as follows:

[0031] The iron powder particles, ammonium carbonate, and water are stirred evenly under a water bath heating at 35 °C, and then continue to be subjected to ultrasonic dispersion treatment to obtain a mixed solution; among them, the mass ratio of the iron powder particles, ammonium carbonate, and water is 3:5:60;

[0032] Continue to cool the mixed solution after dispersion treatment to 15 °C at a cooling rate of 1 °C per minute in an ultrasonic dispersion environment;

[0033] Stir the mixed solution after cooling treatment with an electromagnet. The particles adsorbed by the electromagnet are iron powder particles wrapped by ammonium carbonate crystals.

[0034] A further technical solution of the present invention is that in the preparation process of the primer coating, the mass ratio of polydimethylsiloxane, dichloromethane, dimethyl silicone oil and silane coupling agent is 10:20:8:1.

[0035] A further technical solution of the present invention is that when spraying the topcoat on the surface of the semi-cured primer and heating for curing, the temperature is raised from 95 °C to 150 °C within 30 minutes and maintained at 150 °C for 10 minutes.

[0036] Beneficial effects

[0037] The beneficial effects of the present invention are as follows: Through the partially covered double-layer coupling structure and preparation process, the present invention realizes the efficient coordination of anti-icing and low adhesion force, and has the characteristics of excellent performance, flexible preparation and low cost, providing a breakthrough solution for anti-icing technology in fields such as polar ships and aerospace equipment. The specific advantages are analyzed as follows:

[0038] 1. The present invention combines the superhydrophobic topcoat to delay surface icing and the super-slippery primer to reduce ice adhesion force, achieving the synergistic effect of anti-icing and low adhesion force, and effectively solving the industry problem that a single coating cannot take into account both "delayed icing" and "low adhesion". Among them, the lubricating oil locked in the microstructure of the primer is reduced in loss through mechanical interlocking design, significantly prolonging the durability of the super-slippery performance, and is suitable for the polar environment where the waves frequently wash.

[0039] 2. By adjusting the diameter ratio of iron powder particles and silica particles, the present invention realizes the precise control of the exposed area of the primer, meets the polar working conditions requirements of different temperatures, humidities and salt spray concentrations; is applicable to substrates such as metals and composite materials with different roughnesses, and can be extended to multi-field applications such as ships, aerospace equipment and high-voltage cables.

[0040] 3. In the preparation process of the present invention, the primer and the topcoat are sprayed in stages, combined with low-temperature pre-curing (60 °C) and high-temperature final curing (150 °C), ensuring strong coating interface bonding force and stable structure. Using an electromagnet to accurately adsorb and remove iron powder particles, realizing the controllable adjustment of the micro-area distribution on the coating surface, with high process repeatability and simple operation.

[0041] 4. The present invention uses common materials such as polydimethylsiloxane and silicon dioxide. The spraying process does not require complex equipment and is suitable for large-scale industrial production. The iron powder particles used can be recycled, reducing waste generation and meeting environmental protection requirements; the coating does not contain controlled chemicals and is environmentally friendly. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 It is a schematic structural diagram of an anti-icing coating for polar ships with adjustable ice adhesion force in Embodiment 1 of the present invention and a schematic diagram of the contact state of a droplet on the surface of the anti-icing coating;

[0043] Figure 2 It is a top view schematic diagram of an anti-icing coating for polar ships with adjustable ice adhesion force in Embodiment 1 of the present invention;

[0044] Figure 3 It is a micrograph of an anti-icing coating for polar ships with adjustable ice adhesion force in Embodiment 2 of the present invention; (a) A micrograph of an anti-icing coating with the exposed surface of the super-slippery primer and the super-hydrophobic topcoat area accounting for about 50%; (b) A test result diagram of the droplet contact angle;

[0045] Figure 4 It is a micrograph of an anti-icing coating for polar ships with adjustable ice adhesion force in Embodiment 3 of the present invention; (a) A micrograph of an anti-icing coating with the exposed surface of the super-slippery primer and the super-hydrophobic topcoat area accounting for about 30% and 70%; (b) A test result diagram of the droplet contact angle;

[0046] Figure 5 It is a micrograph of an anti-icing coating for polar ships with adjustable ice adhesion force in Embodiment 4 of the present invention; (a) A micrograph of an anti-icing coating with the exposed surface of the super-slippery primer and the super-hydrophobic topcoat area accounting for about 60% and 40%; (b) A test result diagram of the droplet contact angle;

[0047] Figure 6 It is a comparison diagram of ice adhesion forces with different proportions of super-hydrophobic surfaces of the topcoat.

[0048] Description of the reference numerals: 1. Substrate; 2. Primer; 3. Topcoat; 4. Droplet. DETAILED DESCRIPTION OF THE INVENTION

[0049] The embodiments described below by referring to the drawings are exemplary and are intended to explain the present invention and should not be construed as limiting the present invention.

[0050] At present, ship anti-icing technologies can be divided into two types: superhydrophobic coating anti-icing and super-slippery coating anti-icing. Although a superhydrophobic surface can delay surface icing, when ice forms on the superhydrophobic surface, ice crystals will embed inside the microstructures of the superhydrophobic surface, greatly increasing the adhesion force of the ice. A super-slippery surface can greatly reduce the ice adhesion force, but it cannot prevent icing, and the oil film on its surface will quickly be lost under the long-term scouring of rainwater and sea waves, losing the super-slippery effect.

[0051] For example, the publicly disclosed shape memory anti-icing composite material film is to solve the problem of increased ice adhesion force on the superhydrophobic surface after icing.

[0052] The publicly disclosed super-slippery coating with a photothermal function adds a photothermal function on the basis of the super-slippery coating, but the photothermal use has great limitations and it cannot prevent icing on cloudy days.

[0053] The publicly disclosed anti-icing coating with hydrophilic and hydrophobic intervals has a hydrophobic part on the surface that makes water easy to slide off the surface, while the hydrophilic part can inhibit the icing of surface water and form a water lubricating layer, thus having low adhesion. However, its hydrophilic part is a traditional water film. When the surface is in a low-temperature environment for a long time, ice will form on the surface, losing the hydrophilic effect and instead increasing the ice adhesion force.

[0054] The publicly disclosed superhydrophobic anti-icing coating still has not solved the problem of the increased adhesion force on the superhydrophobic surface after icing.

[0055] The publicly disclosed super-slippery coating has not solved the problem of preventing icing on the super-slippery surface.

[0056] Based on the above problems, the present invention provides a polar ship anti-icing coating capable of adjusting the ice adhesion force, which includes a double-layer coupling structure composed of a primer and a topcoat, and the coverage area of the topcoat on the primer is in a dynamically controllable form; the primer is a super-slippery surface, and its surface microstructure prevents ice crystals from embedding inside the microstructure by locking lubricating oil. The topcoat is a superhydrophobic surface obtained by directionally screening and removing magnetic particles in the topcoat paint. The micro-region distribution of the superhydrophobic surface is complementary to the spatial arrangement of the removed magnetic particles, and the exposure area of the super-slippery surface primer is regulated by controlling the spatial distribution of the magnetic particles.

[0057] Specifically, the primer is a lubricating layer with a microstructure filled with lubricating oil formed by spraying primer paint on the substrate surface. The primer paint is mixed with polydimethylsiloxane, dichloromethane, dimethyl silicone oil and silane coupling agent.

[0058] Specifically, the topcoat is a superhydrophobic surface formed by heating the topcoat paint sprayed on the primer surface to cover part of the primer, so that part of the primer is exposed; the topcoat paint is composed of superhydrophobic particles, iron powder particles wrapped with ammonium carbonate crystals, and ethanol.

[0059] The present invention provides a method for preparing an anti-icing coating for polar ships with adjustable ice adhesion force, and the specific steps are as follows:

[0060] Prepare the topcoat paint: Mix superhydrophobic particles, iron powder particles wrapped with ammonium carbonate crystals, and ethanol at room temperature, stir, and then perform ultrasonic dispersion treatment to obtain the topcoat paint; among them, the superhydrophobic particles and the iron powder particles wrapped with ammonium carbonate crystals are used as solute particles, and ethanol is used as a solvent, and the mass ratio of the solute particles to the solvent is 2:5;

[0061] Prepare the primer paint: Mix polydimethylsiloxane, dichloromethane, and dimethyl silicone oil at room temperature, stir, and then perform ultrasonic dispersion treatment to obtain a paint precursor solution. Mix the paint precursor solution with a silane coupling agent and stir evenly to obtain the primer paint;

[0062] Spray the primer paint on the surface of the substrate and dry it at 60 °C for 15 minutes to obtain a semi-cured primer;

[0063] Spray the topcoat paint on the surface of the semi-cured primer, heat and cure it, and then cool it to room temperature; during the heating process, the ammonium carbonate crystals coated on the surface of the iron powder particles volatilize, exposing the iron powder particles;

[0064] Use an electromagnet to suck out the exposed iron powder particles, so that the primer at the position where the iron powder particles are located is exposed, and an anti-icing coating with a double-layer coupling of primer and topcoat is obtained.

[0065] In summary, the adhesion force of the traditional superhydrophobic coating surges after icing, while in the present invention, the exposed part of the super-slippery primer directly contacts the ice layer, significantly reducing the energy consumption for de-icing. The traditional super-slippery coating relies on the oil film which is easy to lose, and the present invention improves the lubrication durability through micro-structure oil locking and double-layer coupling design.

[0066] The above technical solutions will be further described below with reference to the accompanying drawings:

[0067] Example 1:

[0068] Refer to Figure 1 and Figure 2As shown in the figure, an anti-icing coating for polar ships with adjustable ice adhesion force in this embodiment consists of two parts: a primer 2 and a topcoat 3. After the primer 2 is sprayed, the surface of the substrate 1 can be transformed into a super-slippery surface, and the internal microstructure of this surface is filled with lubricating oil, which can effectively prevent ice crystals from embedding into the internal microstructure after icing, thus achieving the effect of reducing ice adhesion force. The topcoat 3 is a super-hydrophobic surface, which can effectively prevent the surface from being wetted by liquids; the topcoat paint is sprayed on the upper layer of the super-slippery primer 2, but the super-hydrophobic topcoat 3 does not completely cover the super-slippery primer, but has certain voids, which can expose part of the super-slippery primer surface so that it can contact with ice. At the same time, the exposed area of the super-slippery primer can be adjusted by adjusting the composition of the topcoat; the contact state of the liquid droplets on the surface of the anti-icing coating is as Figure 1 shown. The present invention has an anti-icing coating with super-hydrophobic on the top layer and super-slippery on the bottom layer, and solves the problem of its preparation.

[0069] The preparation method of an anti-icing coating for polar ships with adjustable ice adhesion force described in this embodiment includes the following steps:

[0070] Step 1: Prepare polydimethylsiloxane, dichloromethane, dimethyl silicone oil, silane coupling agent, 10-micron porous silica particles, sodium hydroxide, perfluorotriethoxysilane, ethanol, deionized water, ammonium carbonate, and iron powder with different diameters (the diameter is between 0.5 microns and 100 microns) for standby.

[0071] Preparation of the topcoat:

[0072] Step 2: Prepare a sodium hydroxide solution with a concentration of 5 mol / L, slowly add 10-micron porous silica particles into the sodium hydroxide solution, and react at 95 °C for 10 minutes. During this process, the mouth of the beaker needs to be sealed to prevent gas volatilization. After the reaction is completed, silica particles with a nano-scale micro surface structure are obtained. Then filter out the silica particles with a nano-scale micro surface structure, ultrasonically clean them with deionized water for 20 minutes, and put them in an oven to dry for standby.

[0073] During the above process, the surface material of the porous silica particles will react under the action of sodium hydroxide. Among them, the surface material of the porous silica particles will continuously react with sodium hydroxide to generate sodium silicate, which will fall off from the surface of the porous silica particles, thus forming a smaller nano-scale micro structure on the surface of the porous silica particles.

[0074] Step 3: Take a mixture of perfluorotriethoxysilane and ethanol with a mass ratio of 1:100, add the dried silica particles with a nano-scale micro surface structure, stir at room temperature for 3 hours, then filter them out and dry them in an oven at 120 °C for 3 hours to complete the low surface energy treatment. At this time, silica nanoparticles with dual hydrophobic properties are obtained.

[0075] Step 4: Take iron powder particles, ammonium carbonate, and water with a mass ratio of 3:5:60 and add them to a beaker. Stir evenly under a water bath heating at 35 °C; then ultrasonically disperse for half an hour. During this process, use the water bath method to maintain the solution temperature at around 35 °C. After half an hour, continue to cool down to 15 °C at a cooling rate of 1 °C per minute in the ultrasonically dispersed environment. Then, place an electromagnet on the side wall of the beaker and stir for about 10 minutes. Pour out the particles and solution in the beaker that are not adsorbed by the electromagnet. The remaining particles adsorbed by the electromagnet are iron powder particles wrapped by ammonium carbonate crystals.

[0076] Step 5: Take iron powder particles wrapped by ammonium carbonate crystals, silica nanoparticles with dual hydrophobic properties, and ethanol with a certain mass ratio. Stir with a magnetic stirrer at room temperature (25 °C) for 1 hour, and then ultrasonically disperse at room temperature for 30 minutes. During this period, use a water bath for temperature control to obtain the topcoat paint. The solution should be sealed during this process to prevent volatilization.

[0077] It should be noted that in this step, the mass ratio between the solute particles (iron powder particles wrapped by ammonium carbonate crystals, silica nanoparticles with dual hydrophobic properties) and the solvent (ethanol) is about 2:5. The ratio between the iron powder particles wrapped by ammonium carbonate crystals and the silica nanoparticles with dual hydrophobic properties can be adjusted between 1:18 and 5:1 to achieve different coverage area ratios for the primer.

[0078] Preparation of primer:

[0079] Step 6: Take polydimethylsiloxane, dichloromethane, and dimethyl silicone oil with a mass ratio of 5:10:4, and add them to the beaker in sequence. Stir with a magnetic stirrer at room temperature for 30 minutes, and cover the beaker with plastic wrap to prevent evaporation. After stirring, ultrasonically disperse for 30 minutes to obtain the coating precursor solution.

[0080] Spray coating:

[0081] Step 7: Add a silane coupling agent to the coating precursor solution prepared in Step 6. The mass ratio between polydimethylsiloxane, dichloromethane, dimethyl silicone oil, and the silane coupling agent is 10:20:8:1. After stirring for 15 minutes, obtain the primer coating. Spray the primer coating on the surface of the substrate to be sprayed, control the spraying thickness within 20 microns, and then place it in an oven and dry at 60 °C for 15 minutes to obtain a semi-cured primer.

[0082] Step 8: Spray the topcoat paint prepared in Step 5 on the surface of the semi-cured primer, with a spraying thickness of 10 microns.

[0083] Step 9: Place the substrate sprayed with primer and topcoat in an oven, increase the temperature from 95 degrees Celsius to 150 degrees Celsius within 30 minutes, maintain 150 degrees Celsius for 10 minutes, then take it out and cool it down to room temperature.

[0084] Step 10: Use an electromagnet to remove the iron powder particles on the surface of the coating prepared in step 9 from the surface of the substrate. At this time, the entire coating is prepared.

[0085] Specifically, the method for adjusting the coverage area of ​​the topcoat on the primer comprises the following steps:

[0086] The super-hydrophobic particles in the topcoat coating were determined to be 10-micron-sized porous silica particles;

[0087] Set the exposed area ratio of the primer as needed and use the following formula to calculate the iron powder particle diameter:

[0088]

[0089] in, is the primer exposed area ratio, is the diameter of porous silica particles, is the diameter of iron powder particles;

[0090] The mass ratio of porous silica particles to iron powder particles is calculated based on the density ratio of porous silica particles to iron powder particles, and a topcoat coating is prepared according to the obtained mass ratio, thereby obtaining an anti-icing coating with the coverage area of ​​the topcoat on the primer controlled as needed.

[0091] It should be noted that the substrate to be sprayed should have a roughness of R5 to R10 to ensure the adhesion between the primer and the substrate. The diameter of the 10 micron-level porous silica nanoparticles mentioned in step one can be between 5 and 500 microns, and the porous structure is to maintain the roughness of the surface of the silica particles. In step two, the porous silica particles are treated with sodium hydroxide to prepare nanoscale microstructures. Under this parameter, it can be ensured that the silica particles are not excessively corroded, and nanoscale composite microstructures can be produced. While ensuring better super-phobic properties, the adhesion between the primer is stronger. After spraying the primer in step six, it is placed in an oven at 60 degrees Celsius for 15 minutes and then taken out, in order to make it initially formed but not completely solidified. After spraying the topcoat, the silica particles of the topcoat can be trapped in the primer to form a strong mechanical interlocking, and the combination between the back paint and the primer after heating again is more firmly.

[0092] The method mentioned in the present invention is easy to prepare, and the coating only needs to be sprayed, the steps are simple, and it can be widely used in the anti-icing and anti-corrosion of equipment in the fields of aerospace, navigation, etc.

[0093] Embodiment 2:

[0094] The specific steps for preparing an anti-icing coating with a super-slippery primer surface and a super-hydrophobic topcoat surface each accounting for about 50% on the aluminum surface are as follows:

[0095] Step 1: Prepare polydimethylsiloxane, dichloromethane, dimethyl silicone oil, silane coupling agent, 10-micron porous silica particles, sodium hydroxide, perfluorotriethoxysilane, ethanol, deionized water, ammonium carbonate, and 10-micron diameter iron powder particles for standby.

[0096] Topcoat preparation:

[0097] Step 2: Configure a sodium hydroxide solution with a concentration of 5 mol / L, slowly add 10-micron porous silica particles to the sodium hydroxide solution, react at 95 °C for 10 minutes. During this process, cover the beaker mouth to prevent gas volatilization. After the reaction is completed, silica particles with a nano-scale micro surface structure are obtained. Then filter out the silica particles with a nano-scale micro surface structure, ultrasonically clean them with deionized water for 20 minutes, and place them in an oven for drying for standby.

[0098] In the above process, the surface material of the porous silica particles will react under the action of sodium hydroxide. Among them, the surface material of the porous silica particles will continuously react with sodium hydroxide to generate sodium silicate and fall off from the surface of the porous silica particles, thereby forming a smaller nano-scale micro structure on the surface of the porous silica particles. In this process, there is a complex relationship between whether a uniform nano microstructure can be formed on the surface of the porous silica particles and the concentration of sodium hydroxide, the reaction time, the diameter of the porous silica particles, and the porosity of the porous silica particles. It is necessary to operate according to the ratio proposed in this application.

[0099] Step 3: Mix perfluorotriethoxysilane and ethanol with a mass ratio of 1:100, then add the dried silica particles with a nano-scale micro surface structure, stir at room temperature for 3 hours, and then filter them out and place them in an oven at 120 °C for drying for 3 hours to complete the low surface energy treatment. At this time, silica nanoparticles with dual hydrophobic properties are obtained.

[0100] Step 4: Add iron powder particles, ammonium carbonate, and water with a mass ratio of 3:5:60 to a beaker, stir evenly under a water bath heating at 35 °C; then ultrasonically disperse for half an hour. During this process, use the water bath method to maintain the solution temperature at about 35 °C; after half an hour, during the ultrasonic dispersion process, cool down at a rate of 1 °C per minute to 15 °C, and then place an electromagnet on the side wall of the beaker and stir for about 10 minutes. Pour out the particles and solution in the beaker that are not adsorbed by the electromagnet. The remaining particles adsorbed by the electromagnet are iron powder particles wrapped with ammonium carbonate crystals.

[0101] Step Five: Take iron powder particles wrapped with ammonium carbonate crystals, silica nanoparticles with dual hydrophobicity, and ethanol with a mass ratio of 1:3.6:11.5. Stir them with a magnetic stirrer at room temperature of 25 °C for 1 hour, and ultrasonically disperse them at room temperature for 30 minutes. During this process, use a water bath to control the temperature to obtain the topcoat paint. The solution should be sealed to prevent volatilization.

[0102] Primer Preparation:

[0103] Step Six: Take polydimethylsiloxane, dichloromethane, and dimethyl silicone oil with a mass ratio of 5:10:4. Add them to a beaker in sequence, stir with a magnetic stirrer at room temperature for 30 minutes, and cover the beaker with plastic wrap to prevent evaporation. After stirring, ultrasonically disperse for 30 minutes to obtain the coating precursor solution.

[0104] Spray Coating:

[0105] Step Seven: Add a silane coupling agent to the coating precursor solution prepared in Step Six. The mass ratio between polydimethylsiloxane, dichloromethane, dimethyl silicone oil, and the silane coupling agent is 10:20:8:1. After stirring for 15 minutes, spray it on the surface of the substrate to be sprayed with a spray gun. Control the spraying thickness at 20 microns, and then put it into an oven and dry it at 60 °C for 15 minutes to obtain a semi-cured primer.

[0106] Specific spraying parameters are: the spray gun air pressure is set at 2.8 bar, the spraying height is about 25 cm, the moving speed is about 2 cm / s, the spraying flow rate is 80 ml / min, and the nozzle diameter is selected as 1 mm.

[0107] Step Eight: Spray the topcoat paint prepared in Step Five on the surface of the semi-cured primer, and the spraying thickness is 10 microns.

[0108] Specific spraying parameters are: the spray gun air pressure is set at 2.8 bar, the spraying height is about 25 cm, the moving speed is about 4 cm / s, the spraying flow rate is 60 ml / min, and the nozzle diameter is selected as 1 mm.

[0109] Step Nine: Put the substrate sprayed with the primer paint and the topcoat paint into an oven, raise the temperature from 95 °C to 150 °C within 30 minutes, keep it at 150 °C for 10 minutes, and then take it out and cool it down to room temperature.

[0110] Step Ten: Use an electromagnet to remove the iron powder particles on the surface of the coating prepared in Step Nine from the substrate surface. At this time, the entire coating preparation is completed, and the surface of the coating is as Figure 3 shown.

[0111] In this embodiment, the superhydrophobic particles in the topcoat paint are determined to be 10-micron porous silica particles;

[0112] Set the exposed area ratio of the primer as needed, and calculate the iron powder particle diameter using the following formula:

[0113]

[0114] Wherein, is the exposed area ratio of the primer, is the diameter of the porous silica particles, is the diameter of the iron powder particles; here, take as 50%, as 10 microns. At this time, it can be calculated that is 10 microns.

[0115] According to the density ratio of the porous silica particles and the iron powder particles being approximately 1:3.6, the mass ratio of the porous silica particles and the iron powder particles can be calculated as 3.6:1 at this time. Prepare the topcoat paint according to the obtained mass ratio, and an anti-icing coating that can control the coverage area of the topcoat on the primer as needed can be obtained.

[0116] From Figure 6 it can be seen that when the proportion of the superhydrophobic topcoat is 50%, the adhesion force of the surface ice is about 95 kPa.

[0117] Example 3:

[0118] The specific steps for preparing an anti-icing coating with a super-slippery primer surface and a superhydrophobic topcoat area ratio of approximately 30%:70% on the substrate surface are as follows:

[0119] Step 1: Prepare polydimethylsiloxane, dichloromethane, dimethyl silicone oil, silane coupling agent, 10-micron porous micron silica particles, sodium hydroxide, perfluorotriethoxysilane, ethanol, deionized water, ammonium carbonate, and 6-micron diameter iron powder particles for standby.

[0120] Topcoat preparation:

[0121] Step 2: Configure a sodium hydroxide solution with a concentration of 5 mol / L, slowly add 10-micron porous silica particles to the sodium hydroxide solution, and react at 95 °C for 10 minutes. During this process, the mouth of the beaker needs to be sealed to prevent gas volatilization. After the reaction is completed, silica particles with a nano-scale micro surface structure are obtained. Then filter out the silica particles with a nano-scale micro surface structure, ultrasonically clean them with deionized water for 20 minutes, and put them in an oven to dry for standby.

[0122] In the above process, the surface material of the porous silica particles will react under the action of sodium hydroxide. Among them, the surface material of the porous silica particles will continuously react with sodium hydroxide to generate sodium silicate and fall off from the surface of the porous silica particles, thereby forming a finer nano-scale microstructure on the surface of the porous silica. In this process, there is a complex relationship between whether a uniform nano-microstructure can be formed on the surface of the porous silica particles and the concentration of sodium hydroxide, the reaction time, the diameter of the porous silica particles, and the porosity of the porous silica particles. It is necessary to operate according to the ratio proposed in this application.

[0123] Step 3: Mix perfluorotriethoxysilane and ethanol with a mass ratio of 1:100, and then put in the dried silica particles with a nano-scale micro surface structure. Stir at room temperature for 3 hours, then filter it out and dry it in an oven at 120 °C for 3 hours to complete the low surface energy treatment. At this time, silica nanoparticles with dual hydrophobic properties are obtained.

[0124] Step 4: Add iron powder particles, ammonium carbonate, and water with a mass ratio of 3:5:60 to a beaker, and stir evenly under a water bath heating at 35 °C; then ultrasonically disperse for half an hour. During this process, the water bath method is used to maintain the solution temperature at about 35 °C; after half an hour, during the ultrasonic dispersion process, the temperature is decreased at a rate of 1 °C per minute to 15 °C, and then an electromagnet is placed on the side wall of the beaker and stirred for about 10 minutes. Pour out the particles and solution in the beaker that are not adsorbed by the electromagnet. The remaining particles adsorbed by the electromagnet are iron powder particles wrapped with ammonium carbonate crystals.

[0125] Step 5: Take the iron powder particles wrapped with ammonium carbonate crystals prepared in Step 4, the silica nanoparticles with dual hydrophobic properties prepared in Step 3, and ethanol with a mass ratio of 7.7:10:44.25, and stir with a magnetic stirrer at room temperature of 25 °C for 1 hour, and ultrasonically disperse at room temperature for 30 minutes. During this period, the water bath is used for temperature control. The solution should be sealed during this process to prevent its volatilization.

[0126] Primer preparation:

[0127] Step 6: Take polydimethylsiloxane, dichloromethane, and dimethyl silicone oil with a mass ratio of 5:10:4, add them to the beaker in sequence, stir with a magnetic stirrer at room temperature for 30 minutes, and cover the beaker with plastic wrap to prevent evaporation. After stirring, ultrasonically disperse for 30 minutes to obtain a coating precursor solution.

[0128] Spray coating:

[0129] Step 7: Add a silane coupling agent to the coating precursor solution stirred in Step 6. The mass ratio among dimethylsiloxane, dichloromethane, dimethyl silicone oil and the silane coupling agent is 10:20:8:1. After stirring for 15 minutes, spray it onto the surface of the substrate to be sprayed using a spray gun. Control the spraying thickness at 20 microns, and then put it into an oven and dry it at 60 °C for 15 minutes to obtain a semi-cured primer.

[0130] The specific spraying parameters are as follows: the air pressure of the spray gun is set at 2.8 bar, the spraying height is about 25 cm, the moving speed is about 2 cm / s, the spraying flow rate is 80 ml / min, and the nozzle diameter is selected as 1 mm.

[0131] Step 8: Spray the topcoat paint prepared in Step 5 onto the surface of the semi-cured primer. The spraying thickness is 10 microns.

[0132] The specific spraying parameters are as follows: the air pressure of the spray gun is set at 2.8 bar, the spraying height is about 25 cm, the moving speed is about 4 cm / s, the spraying flow rate is 60 ml / min, and the nozzle diameter is selected as 1 mm.

[0133] Step 9: Put the substrate sprayed with the primer paint and the topcoat paint into an oven, raise the temperature from 95 °C to 150 °C within 30 minutes, keep it at 150 °C for 10 minutes, and then take it out and cool it down to room temperature.

[0134] Step 10: Use an electromagnet to remove the iron powder particles on the surface of the coating prepared in Step 9 from the substrate surface. At this time, the entire coating preparation is completed, and the surface of the coating is as Figure 4 shown.

[0135] In this embodiment, the superhydrophobic particles in the topcoat paint are determined to be 10-micron porous silica particles;

[0136] Set the exposed area ratio of the primer as needed, and calculate the iron powder particle diameter using the following formula:

[0137]

[0138] where, is the exposed area ratio of the primer, is the diameter of the porous silica particles, is the diameter of the iron powder particles; here, take as 30%, as 10 microns. At this time, the calculated is about 6 microns.

[0139] According to the density ratio of porous silica particles to iron powder particles being approximately 1:3.6, the mass ratio of porous silica particles to iron powder particles can be calculated as 10:7.7 at this time. By preparing the topcoat paint according to the obtained mass ratio, an anti-icing coating that can control the coverage area of the topcoat on the primer as required can be obtained.

[0140] From Figure 6 It can be seen that when the proportion of the superhydrophobic topcoat is 70%, the adhesion force of the surface ice is about 136 kPa.

[0141] Example 4:

[0142] The specific steps for preparing an anti-icing coating with a super-slippery primer surface and a proportion of the superhydrophobic topcoat area of about 60% and 40% on the substrate are as follows:

[0143] Step 1: Prepare polydimethylsiloxane, dichloromethane, dimethyl silicone oil, silane coupling agent, 10-micron porous silica particles, sodium hydroxide, perfluorotriethoxysilane, ethanol, deionized water, ammonium carbonate, and 12-micron diameter iron powder particles for later use.

[0144] Topcoat preparation:

[0145] Step 2: Configure a sodium hydroxide solution with a concentration of 5 mol / L. Slowly add 10-micron porous silica particles to the sodium hydroxide solution and react at 95 °C for 10 minutes. During this process, the mouth of the beaker needs to be covered to prevent gas volatilization. After the reaction is completed, silica particles with a nano-scale micro surface structure are obtained. Then filter out the silica particles with a nano-scale micro surface structure, ultrasonically clean them with deionized water for 20 minutes, and put them in an oven to dry for later use.

[0146] In the above process, the surface material of the porous silica particles will react under the action of sodium hydroxide. Among them, the surface material of the porous silica particles will continuously react with sodium hydroxide to generate sodium silicate and fall off from the surface of the porous silica particles, thereby forming a smaller nano-scale micro structure on the surface of the porous silica particles. In this process, there is a complex relationship between whether a uniform nano-scale micro structure can be formed on the surface of the porous silica particles and the concentration of sodium hydroxide, the reaction time, the diameter of the porous silica particles, and the porosity of the porous silica particles. It is necessary to operate according to the ratio proposed in this application.

[0147] Step 3: Mix perfluorotriethoxysilane and ethanol in a mass ratio of 1:100, then put in the dried silica particles with a nano-scale micro surface structure, stir at room temperature for 3 hours, and then filter them out and dry them in an oven at 120 °C for 3 hours to complete the low surface energy treatment. At this time, silica nanoparticles with dual hydrophobic properties are obtained.

[0148] Step 4: Take iron powder particles, ammonium carbonate, and water with a mass ratio of 3:5:60 and add them to a beaker. Stir evenly under a water bath heating at 35 °C; then ultrasonically disperse for half an hour. During this process, use the water bath method to maintain the solution temperature at about 35 °C. After half an hour, during the ultrasonic dispersion process, cool down to 15 °C at a cooling rate of 1 °C per minute. Then, place an electromagnet on the side wall of the beaker and stir for about 10 minutes. Pour out the particles and solution in the beaker that are not adsorbed by the electromagnet. The remaining particles adsorbed by the electromagnet are iron powder particles wrapped by ammonium carbonate crystals.

[0149] Step 5: Take iron powder particles wrapped by ammonium carbonate crystals, silica nanoparticles with dual hydrophobic properties, and ethanol with a mass ratio of 6.2:1:18. Stir with a magnetic stirrer at room temperature (25 °C) for 1 hour, and ultrasonically disperse at room temperature for 30 minutes. During this period, use a water bath for temperature control to obtain the topcoat paint. The solution should be sealed during this process to prevent volatilization.

[0150] Primer preparation:

[0151] Step 6: Take polydimethylsiloxane, dichloromethane, and dimethyl silicone oil with a mass ratio of 5:10:4, and add them to the beaker in sequence. Stir with a magnetic stirrer at room temperature for 30 minutes, and cover the beaker with plastic wrap to prevent evaporation. After stirring well, ultrasonically disperse for 30 minutes to obtain the coating precursor solution.

[0152] Spray coating:

[0153] Step 7: Add a silane coupling agent to the coating precursor solution stirred well in Step 6. The mass ratio between polydimethylsiloxane, dichloromethane, dimethyl silicone oil, and the silane coupling agent is 10:20:8:1. After stirring for 15 minutes, spray it on the surface of the substrate to be sprayed using a spray gun. Control the spraying thickness at 20 microns, and then place it in an oven and dry at 60 °C for 15 minutes to obtain a semi-cured state primer.

[0154] The specific spraying parameters are: the spray gun air pressure is set at 2.8 bar, the spraying height is about 25 cm, the moving speed is about 2 cm / s, the spraying flow rate is 80 ml / min, and the nozzle diameter is selected as 1 mm.

[0155] Step 8: Spray the topcoat paint prepared in Step 5 on the surface of the semi-cured state primer, with a spraying thickness of 10 microns.

[0156] The specific spraying parameters are: the spray gun air pressure is set at 2.8 bar, the spraying height is about 25 cm, the moving speed is about 4 cm / s, the spraying flow rate is 60 ml / min, and the nozzle diameter is selected as 1 mm.

[0157] Step 9: Place the substrate sprayed with the primer coating and the topcoat coating into an oven, raise the temperature from 95 °C to 150 °C within 30 minutes, maintain at 150 °C for 10 minutes, and then take it out and cool it down to room temperature.

[0158] Step 10: Use an electromagnet to remove the iron powder particles on the surface of the coating prepared in Step 9 from the substrate surface. At this time, the entire coating preparation is completed, and the surface of the coating is as Figure 5 shown.

[0159] In this embodiment, the superhydrophobic particles in the topcoat coating are determined to be 10-micron porous silica particles;

[0160] Set the exposed area ratio of the primer as needed, and calculate the diameter of the iron powder particles using the following formula:

[0161]

[0162] where, is the exposed area ratio of the primer, is the diameter of the porous silica particles, is the diameter of the iron powder particles; here, take as 60%, as 10 microns. At this time, the calculated is about 12 microns.

[0163] According to the density ratio of the porous silica particles to the iron powder particles being about 1:3.6, the mass ratio of the porous silica particles to the iron powder particles can be calculated as 1:6.2 at this time. Prepare the topcoat coating according to the obtained mass ratio, and an anti-icing coating that can control the coverage area of the topcoat on the primer as needed can be obtained.

[0164] It can be seen from Figure 6 that when the proportion of the superhydrophobic topcoat is 40%, the adhesion force of the surface ice is about 76 kPa.

[0165] In the above embodiment, when the exposed area ratios of the primer and the topcoat are both 50%, the surface electron micrograph is as shown in Figure 3 (a) therein, the surface porosity is moderate, and the surface contact angle is as shown in Figure 3 (b) therein and can reach about 150°; when the exposed area ratios of the primer and the topcoat reach 30% and 70% respectively, the surface micrograph is as shown in Figure 4 (a) therein, the surface porosity is low, and the surface contact angle is as shown in Figure 4 (b) therein and can reach about 129°; when the exposed area ratios of the primer and the topcoat are 60% and 40% respectively, the surface electron micrograph is as shown in Figure 5 (a) therein, the surface porosity is high, and the surface contact angle is as shown in Figure 5 (b) therein and can reach about 159°. At the same time, asFigure 6 As shown, when the surface is completely covered by the super-slippery surface, the adhesion force of ice is the lowest, about 15 kPa. Although it has the lowest ice adhesion force at this time, the surface has poor hydrophobicity, and the lubricating fluid is likely to be lost under long-term rain washing, resulting in the failure of the surface anti-icing. When the surface is completely covered by the super-hydrophobic paint, the ice adhesion force after the surface freezes is the largest, about 208 kPa. It can be seen that only when the primer super-slippery surface and the topcoat super-hydrophobic surface appear alternately, that is, the anti-icing coating for polar ships with adjustable ice adhesion force proposed in the present invention can achieve both a lower ice adhesion force and a controllable adjustment of better super-hydrophobic characteristics.

[0166] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention without departing from the principles and purposes of the present invention.

Claims

1. A polar ship anti-icing coating with adjustable ice adhesion, characterized in that: It includes a double-layer coupling structure consisting of a primer and a topcoat, wherein the coverage area of ​​the topcoat on the primer is in a dynamically controllable form; The primer has an ultra-slip surface, and its surface microstructure prevents ice crystals from embedding into the microstructure by locking lubricating oil; The topcoat is a superphobic surface obtained by directional screening and removal of magnetic particles in the topcoat coating, the micro-area distribution of the superphobic surface and the removed magnetic particles are complementary in spatial arrangement, and the exposed area of ​​the superslippery surface primer is regulated by controlling the spatial distribution of the magnetic particles; The topcoat is a super-hydrophobic surface formed by heating a topcoat coating sprayed on the surface of the primer to cover part of the primer, so that part of the primer is exposed; the topcoat coating is composited by super-hydrophobic particles, iron powder particles wrapped by ammonium carbonate crystals, and ethanol; Method for adjusting the coverage area of ​​the topcoat on the primer: The super-hydrophobic particles in the topcoat coating were determined to be 10-micron-sized porous silica particles; Set the exposed area ratio of the primer as needed and use the following formula to calculate the iron powder particle diameter: in, is the primer exposed area ratio, is the diameter of porous silica particles, is the diameter of iron powder particles; According to the density ratio of the porous silica particles and the iron powder particles, the mass ratio of the porous silica particles and the iron powder particles is calculated, and the topcoat coating is prepared according to the obtained mass ratio, so that an anti-icing coating can be obtained with the coverage area of ​​the topcoat on the primer controlled as needed; The spraying thickness of the primer coating is 20 microns, and the spraying thickness of the topcoat coating is 10 microns.

2. The polar ship anti-icing coating with adjustable ice adhesion according to claim 1, characterized in that: The primer is an ultra-slip layer of microstructure filled with lubricating oil formed by a primer coating sprayed on the surface of a substrate, and the primer coating is a mixture of polydimethylsiloxane, dichloromethane, dimethyl silicone oil and a silane coupling agent.

3. A method for preparing a polar ship anti-icing coating with adjustable ice adhesion as claimed in claim 1 or 2, characterized in that The specific steps are as follows: Preparation of topcoat coating: super-hydrophobic particles, iron powder particles wrapped by ammonium carbonate crystals, and ethanol are mixed and stirred at room temperature, and then subjected to ultrasonic dispersion treatment to obtain topcoat coating; wherein the super-hydrophobic particles and the iron powder particles wrapped by ammonium carbonate crystals are used as solute particles, ethanol is used as solvent, and the mass ratio of solute particles to solvent is 2:5; Preparation of primer coating: polydimethylsiloxane, dichloromethane and dimethyl silicone oil are mixed and stirred at room temperature, and then subjected to ultrasonic dispersion treatment to obtain a coating precursor liquid, and the coating precursor liquid is mixed and stirred with a silane coupling agent to obtain a primer coating; The primer is sprayed on the surface of the substrate and dried at 60 degrees Celsius for 15 minutes to obtain a semi-cured primer; The topcoat is sprayed on the semi-cured primer surface, and then heated and cured and cooled to room temperature; during the heating process, the ammonium carbonate crystals coated on the surface of the iron powder particles volatilize, exposing the iron powder particles; The exposed iron powder particles are sucked out by an electromagnet, so that the primer at the position where the iron powder particles are located is exposed, thereby obtaining an anti-icing coating with a double layer coupling of primer and topcoat.

4. The method for preparing a polar ship anti-icing coating with adjustable ice adhesion according to claim 3, characterized in that: The specific steps of preparing the topcoat coating are as follows: The surface of porous silica particles is etched with a sodium hydroxide solution to form silica particles with nanoscale micro-surface structures; The silicon dioxide particles with nano-scale micro-surface structures are subjected to low surface energy treatment to obtain silicon dioxide nanoparticles with amphiphobic properties, i.e., superhydrophobic particles; preparing iron powder particles coated with ammonium carbonate crystals; The silicon dioxide nanoparticles with amphiphobic properties, the iron powder particles wrapped by ammonium carbonate crystals and ethanol are mixed and stirred at room temperature, and then subjected to ultrasonic dispersion treatment at room temperature to obtain a topcoat coating.

5. The method for preparing a polar ship anti-icing coating with adjustable ice adhesion according to claim 4, characterized in that: The preparation method of the iron powder particles wrapped by ammonium carbonate crystals is as follows: The iron powder particles, ammonium carbonate and water were stirred uniformly in a water bath heated at 35 degrees Celsius, and then ultrasonically dispersed to obtain a mixed solution; wherein the mass ratio of the iron powder particles, ammonium carbonate and water was 3:5:60; The mixed solution after dispersion treatment is further cooled to 15 degrees Celsius at a cooling rate of 1 degree Celsius per minute under an ultrasonic dispersion environment; The mixed solution after the cooling treatment is stirred by an electromagnet, and the particles adsorbed by the electromagnet are the iron powder particles wrapped by the ammonium carbonate crystals.

6. The method for preparing a polar ship anti-icing coating with adjustable ice adhesion according to claim 5, characterized in that: During the preparation of the primer coating, the mass ratio of polydimethylsiloxane, dichloromethane, dimethyl silicone oil and silane coupling agent is 10:20:8:

1.

7. The method for preparing a polar ship anti-icing coating with adjustable ice adhesion according to claim 6, characterized in that: The topcoat is sprayed on the semi-cured primer surface, and the heating and curing process is to increase the temperature from 95° C. to 150° C. within 30 minutes and maintain the temperature at 150° C. for 10 minutes.

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