A wear-resistant multidimensional micro-nanostructure super-hydrophobic coating and its preparation method

Abstract

The present invention provides a kind of wear-resistant multidimensional micro-nano structure super-hydrophobic coating and preparation method thereof, relate to super-hydrophobic coating technical field.The wear-resistant multidimensional micro-nano structure super-hydrophobic coating includes: the primer applied to substrate surface and the topcoat attached to the primer;Its preparation method includes: Step1. primer raw material mixed and dispersed uniformly, and sprayed on substrate surface;Step2. topcoat raw material mixed and dispersed uniformly, after primer coating surface is dry, the topcoat raw material mixed and dispersed uniformly is sprayed on primer, room temperature curing;Wherein, the primer raw material includes vinyl resin, silicone resin, inorganic filler, solvent, curing agent and auxiliary agent;The topcoat raw material includes super-hydrophobically modified nano-silicon, silicone resin and solvent;And the super-hydrophobically modified nano-silicon at least includes two kinds of particle size particles;The super-hydrophobic coating process of the present invention is simple, convenient construction and good surface wear resistance, strong durability.

Description

Technical Field

[0001] The present invention relates to the technical field of super-hydrophobic coatings, and in particular to a wear-resistant multi-dimensional micro-nanostructure super-hydrophobic coating and a preparation method thereof. Background Art

[0002] Inspired by the lotus effect, superhydrophobic surfaces have been found to possess excellent properties such as self-cleaning, oil-water separation, anti-icing and anti-corrosion. Consequently, superhydrophobic materials have garnered significant attention in recent years. The key to creating superhydrophobic surfaces lies in constructing fine hydrophobic micro- and nanostructures. However, this delicate surface structure makes them susceptible to external damage, resulting in a loss of superhydrophobicity, a significant obstacle hindering their application.

[0003] Wear-resistant superhydrophobic coatings are special materials that not only possess superhydrophobic properties, reducing the adhesion of water droplets, but also possess excellent wear resistance, capable of withstanding the wear and tear of daily use. This material has broad application prospects in a variety of fields, including self-cleaning, anti-icing, and drag reduction. Researchers have been exploring methods to improve the wear resistance of superhydrophobic coatings. For example, by adding special nanomaterials, such as cerium dioxide (CeO2), to the coating, the coating's wear resistance, as well as its resistance to heat and chemical corrosion, can be improved. Furthermore, by optimizing the coating's micro- and nanostructures, its wear resistance can also be enhanced to a certain extent.

[0004] The micro-nano structure of the super-hydrophobic surface is extremely susceptible to external damage, and even a slightly strong wind can destroy this micro-nano structure. At present, there are probably the following methods for improving the mechanical durability of super-hydrophobic surfaces: 1. Microstructure protection method; 2. Self-repairing surface method; 3. Adhesive protection method. For example, Chinese invention patent CN202310123571.3 discloses a super-wear-resistant and weather-resistant shell-like structure super-hydrophobic coating and its preparation method. The specific scheme is to mix alkyd resin, acrylic acid and tetrafluororesin, silane coupling agent and other fillers as a primer, spray HMDS modified nano-silica dispersion on the surface as a topcoat, and obtain a wear-resistant super-hydrophobic surface through multi-layer composite on the bottom surface. Chinese invention patent CN202111095677.4 discloses a wear-resistant and corrosion-resistant super-hydrophobic composite coating and its preparation method. Mica / silica composite powder is modified with silane coupling agent KH560, supplemented with epoxy resin and solvent to obtain a wear-resistant super-hydrophobic surface. Chinese invention patent CN202311312130.4 discloses a method for preparing a highly wear-resistant and water-impact-resistant super-hydrophobic coating. The method uses a nano-silica dispersion and acrylic resin mixed with a silane coupling agent and a solvent to prepare a wear-resistant super-hydrophobic coating that can be impacted more than 10 times by a 300ml water flow at a height of 1.2m.

[0005] Although there are many methods for preparing wear-resistant super-hydrophobic coatings in the prior art and many performance improvements have been made, there are still defects. The main manifestation is that the existing wear-resistant super-hydrophobic coatings generally have complex processes, harsh construction conditions, high costs, and high maintenance costs. It is difficult to achieve large-surface preparation, which restricts the further widespread application and development of wear-resistant super-hydrophobic coatings. Summary of the Invention

[0006] The present invention aims to solve the problems in the prior art of wear-resistant super-hydrophobic coatings, such as complex process, harsh construction conditions, high cost, high maintenance cost, and difficulty in preparing large surfaces. The present invention provides a wear-resistant multi-dimensional micro-nanostructured super-hydrophobic coating with simple process, low cost, convenient construction, good surface wear resistance and strong durability, and a preparation method thereof.

[0007] The technical solution adopted in the present invention is:

[0008] A method for preparing a wear-resistant multi-dimensional micro-nanostructure super-hydrophobic coating comprises the following steps:

[0009] Step 1. Mix and disperse the primer raw materials evenly and spray them on the surface of the substrate;

[0010] Step 2. Mix and disperse the topcoat raw materials evenly. After the primer coating is dry, spray the evenly mixed and dispersed topcoat raw materials on the primer and cure at room temperature.

[0011] The primer raw materials include vinyl resin, silicone resin, inorganic filler, solvent, curing agent and additives; the topcoat raw materials include super-hydrophobic modified nano-silica, silicone resin and solvent; and the super-hydrophobic modified nano-silica contains at least two particle sizes.

[0012] Furthermore, the primer raw materials include: 20% vinyl resin, 10% to 20% silicone resin, 15% to 35% inorganic filler, and the balance solvent A1, curing agent and additives, calculated by weight percentage.

[0013] Furthermore, the inorganic filler includes an inorganic filler B1 and an inorganic filler B2, the inorganic filler B1 is hollow glass microspheres with a particle size of 20-50 μm, and the inorganic filler B2 is hollow glass microspheres with a particle size of 100-150 μm.

[0014] Furthermore, the inorganic filler comprises: 5% to 10% of inorganic filler B1 and 10% to 25% of inorganic filler B2, calculated by weight percentage.

[0015] Furthermore, the topcoat and primer of the wear-resistant multi-dimensional micro-nanostructure super-hydrophobic coating are mutually inlaid structures, and the topcoat and primer form a multi-level rough structure from large micron structure C1, micron structure C2 to nanostructure C3.

[0016] Furthermore, the distance between the mastoids of the large microstructure C1 is 50-150 μm, the distance between the mastoids of the microstructure C2 is 1-5 μm, and the distance between the particles of the nanostructure C3 is 10-1000 nm.

[0017] Furthermore, the topcoat raw materials include: 10-20% silicone resin, 30-50% super-hydrophobic modified nano-silica, 2-4% organotin catalyst and the balance solvent, calculated by weight percentage; the particle size of the nano-silica is 10-1000nm.

[0018] Furthermore, the topcoat raw materials include: 15-20% silicone resin, 30-50% super-hydrophobic modified nano-silica, 2-4% organotin catalyst and the balance solvent, calculated by weight percentage.

[0019] Furthermore, the preparation method of the super-hydrophobic modified nano-silica comprises:

[0020] An alcohol solvent, an alkaline catalyst, and a silicate are sequentially added to a reactor, the temperature is raised to 60±10°C and then maintained constant, the reaction is divided into two parts, and the reaction is carried out for 24 hours and 72 hours respectively. After filtration and drying, unmodified nano-silica of two particle sizes are obtained; the dried nano-silica of two particle sizes is mixed with an alcohol solvent and an ester solvent, and polysiloxane with a molecular weight between 500 and 5w is added, and the reaction is carried out at 80±5°C for 5±0.5 hours to obtain super-hydrophobic nano-silica containing particles of two particle sizes.

[0021] A wear-resistant multidimensional micro-nanostructured super-hydrophobic coating comprises a primer coated on a substrate surface and a topcoat attached to the primer; the preparation process of the wear-resistant multidimensional micro-nanostructured super-hydrophobic coating comprises the preparation method of the wear-resistant multidimensional micro-nanostructured super-hydrophobic coating as described above.

[0022] The beneficial effects of the present invention are:

[0023] 1. The super-hydrophobic coating preparation method of the present invention is simple and easy to operate, convenient for large-scale promotion and application, and its water static contact angle can reach 160°, the rolling angle is less than 5°, and it can withstand 5m / s (6L / min) water flow impact for more than 20min. It can be applied to a variety of substrate surfaces, effectively improving its surface self-cleaning and anti-corrosion properties, and extending the service life of the substrate, thereby solving the problems of complex wear-resistant super-hydrophobic coating process in the prior art, harsh construction conditions, high cost, and high maintenance cost, and it is difficult to achieve large-surface preparation;

[0024] 2. The super-hydrophobic coating of the present invention also relies on the characteristics of super-hydrophobic nanoparticles of different particle sizes in the topcoat to form a "micron-nano" hierarchical structure, and then through the combination of two inorganic fillers with different particle sizes, further forming a "large micron-micron-nano" multi-level micro-nano structure, constructing a multi-level long-term and effective protection mechanism, thereby improving the wear resistance and hydrophobicity of the super-hydrophobic coating as a whole;

[0025] 3. The present invention also utilizes the organic silicone resin in the primer in combination with a curing agent to cure and crosslink to form a flexible substrate, which can effectively mitigate external impact and reduce the loss of super-hydrophobic nanoparticles;

[0026] 4. The present invention also utilizes the modified nano-silica particles in the topcoat to have the ability to produce chemical cross-linking with the topcoat and primer at the same time, which can effectively avoid the coating failure caused by the shedding of the modified nano-silica particles. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0028] Figure 1 Schematic diagram of the structure of a super-hydrophobic coating according to an embodiment of the present invention;

[0029] Figure 2 Schematic diagram of a water impact resistance test according to an embodiment of the present invention. DETAILED DESCRIPTION

[0030] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0031] The disclosure below provides many different embodiments or examples to realize different structures of the present invention. In order to simplify the disclosure of the present invention, the parts and settings of specific examples are described below. Of course, they are only examples, and the purpose is not to limit the present invention.

[0032] In the prior art, there are many methods for preparing wear-resistant super-hydrophobic coatings, but the existing wear-resistant super-hydrophobic coatings generally have complex processes, harsh construction conditions, high costs, high maintenance costs, and difficulty in achieving large-surface preparation.

[0033] The present invention provides a wear-resistant multidimensional micro-nanostructure super-hydrophobic coating and a preparation method thereof, which have simple process, low cost, convenient construction, good surface wear resistance and strong durability. The wear-resistant multidimensional micro-nanostructure super-hydrophobic coating provided by the present invention mainly includes a primer coated on the surface of a substrate and a topcoat attached to the primer.

[0034] The raw materials of the primer mainly include vinyl resin, silicone resin, inorganic filler, solvent A1, curing agent and additives; the raw materials of the topcoat mainly include super-hydrophobic modified nano-silica, silicone resin and solvent.

[0035] The organic silicone resin is one or more of urea polysiloxane resin, methyl polysiloxane resin, hydroxy polysiloxane resin and vinyl polysiloxane resin.

[0036] The inorganic filler includes an inorganic filler B1 having a particle size of 20-50 μm and an inorganic filler B2 having a particle size of 100-150 μm. Inorganic filler B1 and inorganic filler B2 can be different inorganic fillers or the same inorganic filler. Preferably, inorganic filler B1 and inorganic filler B2 are hollow glass microspheres of different particle sizes.

[0037] The solvent A1 is at least one of volatile organic solvents such as ethyl acetate, ethanol, xylene, and carbon tetrachloride.

[0038] The auxiliary agent is at least three of a defoamer, a cosolvent, a dispersant, a catalyst, and an adhesion promoter. The auxiliary agent is mainly used to strengthen the combination of the resin and the inorganic particles in the primer, and the combination of the primer and the topcoat.

[0039] The preparation process of the super-hydrophobic modified nano-silica is as follows: an alcohol solvent, an alkaline catalyst, and a silicate are sequentially added to a reactor, the temperature is raised to 50-70°C and then kept constant, the reaction is divided into two parts, the reaction is carried out for 24 hours and 72 hours respectively, and the unmodified nano-silica of two particle sizes is obtained after filtration and drying; the dried nano-silica of two particle sizes is mixed with an alcohol solvent and an ester solvent, a polysiloxane with a molecular weight between 500 and 5w is added, and the reaction is carried out at 80±5°C for 5±0.5h to obtain super-hydrophobic nano-silica containing particles of two particle sizes. In the preparation process, the alkaline catalyst is ammonia water; the alcohol solvent is one or more of methanol, ethanol, n-butanol, and glycerol, preferably ethanol; the silicate is one or two of tetrabutyl orthosilicate and tetraethyl orthosilicate, preferably ethyl orthosilicate; the ester solvent is one or more of butyl acetate, ethyl acetate, and dimethyl carbonate; and the polysiloxane includes one or more of urea polysiloxane, methyl polysiloxane, hydroxy polysiloxane, and vinyl polysiloxane.

[0040] Preferably, an organic tin catalyst may be added to the topcoat raw material, and the organic tin catalyst is one or more of stannous octoate, dibutyltin dilaurate, and dibutyltin diacetate.

[0041] The preparation method of the wear-resistant multi-dimensional micro-nanostructure super-hydrophobic coating provided by the present invention comprises:

[0042] Step 1. Mix and disperse the primer raw materials evenly, and use a spray gun to spray evenly on the surface of the substrate.

[0043] Step 2. Mix and disperse the topcoat raw materials evenly. After 10 to 30 minutes of primer spraying, wait for the primer coating to dry on the surface; spray the evenly mixed and dispersed topcoat raw materials on the primer and cure at room temperature.

[0044] It should be pointed out that the step of uniformly mixing and dispersing the topcoat raw materials only needs to be completed before spraying the topcoat, and there is no fixed order between the mixing and spraying steps of the primer raw materials.

[0045] The working principle of the present invention includes:

[0046] The present invention utilizes the organic silicone resin in the primer in combination with a curing agent to cure and cross-link to form a flexible substrate, which can effectively mitigate external impact and reduce the loss of super-hydrophobic nanoparticles.

[0047] The present invention utilizes the ability of modified nano-silicon dioxide particles in the topcoat to simultaneously produce chemical crosslinking with the topcoat and primer, which can effectively avoid coating failure caused by the shedding of the modified nano-silicon dioxide particles.

[0048] And as Figure 1As shown in , the present invention also utilizes the characteristics of super-hydrophobic nanoparticles of different particle sizes in the topcoat, and the super-hydrophobic nanoparticles of different particle sizes can be dispersed and reassembled to form a hierarchical structure of "micron-nanometer", which is similar to the bionic structure of lotus leaves and can improve the wear resistance and hydrophobicity of the coating at the same time. At the same time, the inorganic filler in the primer of the present invention also includes at least two different particle sizes, which can meet the conventional filler requirements, and also improve the surface micro-nano structure roughness of the primer, and then form a "large micron" structure layer. Thus after the super-hydrophobic topcoat is attached, the entire coating obtains a multi-level micro-nano structure of "large micron-micron-nanometer", and the papillary spacing of the large micron structure C1 produced by the primer is 50~150μm, and this large micron structure C1 includes a framework structure connected to each other, and a "pocket"-shaped gap is formed between the framework structure. The "pocket"-shaped gap can accommodate the super-hydrophobic topcoat and the mechanically fragile nanostructure C3, and the surface framework structure plays a role in protecting the shell, preventing the nanostructure from being removed by an abrasive larger than the frame size. The papilla spacing of the microstructure C2 under the large microstructure is 1~5μm, and the particle spacing of the nanostructure C3 is 10~1000nm. The strong hydrophobicity and wear resistance of the "micron-nano" hierarchical structure composed of the two can be maintained for a long time and is not easily damaged. Therefore, the three-layer multi-level micro-nano rough structure greatly improves the overall wear resistance and hydrophobicity of the superhydrophobic coating.

[0049] The wear-resistant multidimensional micro-nanostructure super-hydrophobic coating prepared by the present invention has a water static contact angle of up to 160°, a rolling angle of less than 5°, and can withstand the impact of a 5m / s (6L / min) water flow for more than 20 minutes. It can be applied to the surfaces of various substrates, effectively improving their surface self-cleaning and anti-corrosion properties and extending the service life of the substrate. The preparation method of the wear-resistant multidimensional micro-nanostructure super-hydrophobic coating of the present invention is simple and easy to operate, and is convenient for large-scale promotion and application. It has good application prospects in the fields of anti-fouling, anti-icing, etc.

[0050] In order to better understand the present invention, the content of the present invention is further explained below in conjunction with specific examples, but the content of the present invention is not limited to the following examples.

[0051] Example 1

[0052] First, by weight, 20% vinyl resin, 10% silicone resin, 5% 20-50 μm hollow glass microspheres (inorganic filler B1), 10% 100-150 μm hollow glass microspheres (inorganic filler B2), 15% ethanol (solvent A1), 30% cosolvent (auxiliary agent), 6% catalyst (auxiliary agent), 2% dispersant (auxiliary agent), and 2% curing agent were dispersed at room temperature at 800 rpm for 30 minutes to obtain a primer for use. In this example, the cosolvent was ethyl acetate, the catalyst was styrene, the dispersant was BYK-130, and the curing agent was methyl ethyl ketone peroxide.

[0053] Next, super-hydrophobic modified nano-silica was prepared. The preparation process is as follows: an alcohol solvent, an alkaline catalyst, and a silicate ester in a mass ratio of 70:10:20 are added to a reactor in sequence, the temperature is raised to 50°C and then kept constant, and the reaction is carried out for 24 hours and 72 hours respectively. After filtration and drying, unmodified nano-silica of two particle sizes are obtained; the dried nano-silica is mixed with alcohol and ester solvents, and polysiloxane with a molecular weight between 500 and 5w is added. The reaction is carried out at 75°C for 4.5 hours to obtain super-hydrophobic nano-silica.

[0054] Then, 10% hydroxy polysiloxane resin, 30% super hydrophobic modified nano-silica, 2% dibutyltin dilaurate (organotin catalyst) and 58% ethyl acetate (solvent) were dispersed at 1200 r / min for 30 minutes at room temperature to obtain a topcoat for use.

[0055] Finally, use a 5-8Mpa air spray gun to evenly spray the primer on the tinplate substrate. After the primer is dry for 20 minutes, spray the topcoat on top of the primer. After waiting at room temperature for 3 hours, a wear-resistant multi-dimensional micro-nanostructure super-hydrophobic coating sample is obtained.

[0056] Example 2

[0057] First, by weight, 20% vinyl resin, 20% silicone resin, 5% 20-50 μm hollow glass microspheres (inorganic filler B1), 10% 100-150 μm hollow glass microspheres (inorganic filler B2), 15% ethanol (solvent A1), 20% cosolvent (auxiliary agent), 6% catalyst (auxiliary agent), 2% dispersant (auxiliary agent), and 2% curing agent were dispersed at 800 rpm for 30 minutes at room temperature to obtain a primer for use. In this example, the cosolvent was ethyl acetate, the catalyst was styrene, the dispersant was BYK-130, and the curing agent was methyl ethyl ketone peroxide.

[0058] Next, super-hydrophobic modified nano-silica was prepared. The preparation process is as follows: an alcohol solvent, an alkaline catalyst, and a silicate ester in a mass ratio of 70:10:20 are added to a reactor in sequence, the temperature is raised to 70°C and then kept constant, and the reaction is carried out for 24 hours and 72 hours respectively. After filtration and drying, unmodified nano-silica of two particle sizes is obtained; the dried nano-silica is mixed with alcohol and ester solvents, and polysiloxane with a molecular weight between 500 and 5w is added. The reaction is carried out at 80°C for 5 hours to obtain super-hydrophobic nano-silica.

[0059] Then, 15% hydroxy polysiloxane resin, 30% super hydrophobic modified nano-silica, 4% dibutyltin dilaurate (organotin catalyst) and 51% ethyl acetate (solvent) were dispersed at 1200 r / min for 30 minutes at room temperature to obtain a topcoat for use.

[0060] Finally, use a 5-8Mpa air spray gun to evenly spray the primer on the tinplate substrate. After the primer is dry for 20 minutes, spray the topcoat on top of the primer. After waiting at room temperature for 3 hours, a wear-resistant multi-dimensional micro-nanostructure super-hydrophobic coating sample is obtained.

[0061] Example 3

[0062] First, by weight, 20% vinyl resin, 14% silicone resin, 5% 20-50 μm hollow glass microspheres (inorganic filler B1), 10% 100-150 μm hollow glass microspheres (inorganic filler B2), 15% ethanol (solvent A1), 26% cosolvent (auxiliary agent), 6% catalyst (auxiliary agent), 2% dispersant (auxiliary agent), and 2% curing agent were dispersed at room temperature at 800 rpm for 30 minutes to obtain a primer for use. In this example, the cosolvent was ethyl acetate, the catalyst was styrene, the dispersant was BYK-130, and the curing agent was methyl ethyl ketone peroxide.

[0063] Next, super-hydrophobic modified nano-silica was prepared. The preparation process is as follows: an alcohol solvent, an alkaline catalyst, and a silicate ester in a mass ratio of 70:10:20 are added to a reactor in sequence, the temperature is raised to 60°C and then kept constant, and the reaction is carried out for 24 hours and 72 hours respectively. After filtration and drying, unmodified nano-silica of two particle sizes are obtained; the dried nano-silica is mixed with alcohol and ester solvents, and polysiloxane with a molecular weight between 500 and 5w is added. The reaction is carried out at 85°C for 5 hours to obtain super-hydrophobic nano-silica.

[0064] Then, 20% hydroxy polysiloxane resin, 50% super hydrophobic modified nano-silica, 2% dibutyltin dilaurate (organotin catalyst) and 28% ethyl acetate (solvent) were dispersed at 1200 r / min for 30 minutes at room temperature to obtain a topcoat for use.

[0065] Finally, use a 5-8Mpa air spray gun to evenly spray the primer on the tinplate substrate. After the primer is dry for 20 minutes, spray the topcoat on top of the primer. After waiting at room temperature for 3 hours, a wear-resistant multi-dimensional micro-nanostructure super-hydrophobic coating sample is obtained.

[0066] Example 4

[0067] First, by weight, 20% vinyl resin, 20% silicone resin, 10% 20-50 μm hollow glass microspheres (inorganic filler B1), 25% 100-150 μm hollow glass microspheres (inorganic filler B2), 10% ethanol (solvent A1), 5% cosolvent (additive), 6% catalyst (additive), 2% dispersant (additive), and 2% curing agent were dispersed at room temperature at 800 rpm for 30 minutes to obtain a primer for later use. In this example, the cosolvent was ethyl acetate, the catalyst was styrene, the dispersant was BYK-130, and the curing agent was methyl ethyl ketone peroxide.

[0068] Next, super-hydrophobic modified nano-silica was prepared. The preparation process is as follows: an alcohol solvent, an alkaline catalyst, and a silicate ester in a mass ratio of 70:10:20 were added to a reactor in sequence, the temperature was raised to 70°C and then kept constant, and the reaction was carried out for 24 hours and 72 hours respectively. After filtration and drying, unmodified nano-silica of two particle sizes was obtained; the dried nano-silica was mixed with alcohol and ester solvents, and polysiloxane with a molecular weight between 500 and 5w was added. The reaction was carried out at 80°C for 5.5 hours to obtain super-hydrophobic nano-silica.

[0069] Then, 10% hydroxy polysiloxane resin, 30% super hydrophobic modified nano-silica, 2% dibutyltin dilaurate (organotin catalyst) and 58% ethyl acetate (solvent) were dispersed at 1200 r / min for 30 minutes at room temperature to obtain a topcoat for use.

[0070] Finally, use a 5-8Mpa air spray gun to evenly spray the primer on the tinplate substrate. After the primer is dry for 20 minutes, spray the topcoat on top of the primer. After waiting at room temperature for 3 hours, a wear-resistant multi-dimensional micro-nanostructure super-hydrophobic coating sample is obtained.

[0071] Comparative Example 1

[0072] A domestic brand of super-hydrophobic coating: DSAN-S2001-DL (III) D-energy-absorbing super-hydrophobic super-self-cleaning anti-icing new material (double layer). This coating has been widely used in the State Grid.

[0073] Comparative Example 2

[0074] First, by weight, 20% vinyl resin, 20% silicone resin, 5% 20-50 μm hollow glass microspheres (inorganic filler B1), 10% 100-150 μm hollow glass microspheres (inorganic filler B2), 15% ethanol (solvent A1), 20% cosolvent (additive), 6% catalyst (additive), 2% dispersant (additive), and 2% curing agent were dispersed at 800 rpm for 30 minutes at room temperature to obtain a resin-based primer dispersion for later use. In this example, the cosolvent was ethyl acetate, the catalyst was styrene, the dispersant was BYK-130, and the curing agent was methyl ethyl ketone peroxide.

[0075] Next, super-hydrophobic modified nano-silica was prepared. The preparation process is as follows: an alcohol solvent, an alkaline catalyst, and a silicate ester in a mass ratio of 70:10:20 are added to a reactor in sequence, the temperature is raised to 70°C and then kept constant, and the reaction is carried out for 24 hours and 72 hours respectively. After filtration and drying, unmodified nano-silica of two particle sizes is obtained; the dried nano-silica is mixed with alcohol and ester solvents, and polysiloxane with a molecular weight between 500 and 5w is added. The reaction is carried out at 80°C for 5 hours to obtain super-hydrophobic nano-silica.

[0076] Then, 70% of super-hydrophobic modified nano-silica and 30% of ethyl acetate (solvent) were dispersed at 1200 r / min for 30 minutes at room temperature to obtain a topcoat dispersion for use.

[0077] Finally, the prepared superhydrophobic silica topcoat dispersion was poured into the prepared resin-based primer dispersion (mass ratio of topcoat: primer = 5:1), mixed and stirred for 30 minutes, and then the tinplate sheet was used as the substrate. The mixed paint was evenly sprayed on the tinplate base sheet using an air spray gun at room temperature of 25°C. After natural curing, a comparative coating sample was obtained.

[0078] Experimental analysis

[0079] All coating samples were subjected to comparative tests on super-hydrophobicity, long-term water flow impact resistance, short-term water flow impact resistance, and finger friction resistance, and the results are shown in Table 1. The water impact resistance test was set up as follows: Figure 2 As shown, the nozzle diameter is 5mm, the spray distance is 20cm, the long-term water flow resistance water flow velocity is set to 5m / s (6L / min), and the short-term water flow resistance is set to 8m / s (9L / min).

[0080] / Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Water contact angle 158 158 161 158 158 153 Short-term resistance to water flow impact for 10s Water contact angle (after impact) 141 138 158 152 104 123 Long-term water impact resistance 20min water contact angle 101 123 145 124 103 124 Finger friction resistance 300 times without problem 300 times without problem 600 times without problem 600 times without problem After 200 times, the contact angle is less than 150° After 20 times, the contact angle is less than 150°

[0081] Table 1

[0082] After the short-term water flow impact test, the hydrophobic properties of the coatings of Comparative Example 1 and Comparative Example 2 deteriorated significantly, indicating that most of the super-hydrophobic modified nano-silica contained in the coating had fallen off at this time, proving that the bonding strength between the topcoat material and the primer was poor; the finger friction resistance in Comparative Example 2 was the worst, which shows that the super-hydrophobic coating prepared by physical intercalation without the addition of hydroxyl polysiloxane resin has poor wear resistance and is difficult to meet practical applications.

[0083] Comparing Example 1 and Example 2, it is found that the change in the primer resin content does not actually affect the super-hydrophobic property of the coating, and the durability of the super-hydrophobic property is also unrelated to the primer resin content. The primer resin mainly plays a bonding role with the substrate.

[0084] Comparing Examples 2 and 4, it was found that varying the amount of hollow glass microspheres added to the primer significantly affected the coating's short-term water impact resistance. This is primarily because the hollow glass microspheres, after curing, form a "macro-microstructure" on the coating surface: spherical papillae of varying sizes, with grooves between them. These grooves protect the super-hydrophobic nano-topcoat. However, under long-term water impact, the nanoparticles still fall off, and the coating no longer possesses super-hydrophobic properties.

[0085] Comparing Examples 2 and 3, it was found that increasing the amount of silicone resin added to the topcoat significantly improved the coating's short-term and long-term water impact resistance, as well as its resistance to finger rubbing. This is because the silicone resin has strong crosslinking interactions with both the substrate and the superhydrophobic modified particles, firmly adsorbing the superhydrophobic nanoparticles to form micron-sized clusters. Nanoparticles are distributed within these micron-sized clusters, forming a hierarchical "micron-nano" structure. This structure protects the fragile nanoparticles, resulting in excellent resistance to abrasion and water impact.

[0086] In summary, the wear-resistant multi-dimensional micro-nanostructured super-hydrophobic coatings of Examples 1 to 4 prepared according to the present invention all have excellent super-hydrophobicity, water flow impact resistance, and abrasion resistance.

[0087] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely preferred examples of the present invention and are not intended to limit the present invention. Various changes and improvements may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and improvements fall within the scope of the present invention. The scope of protection claimed in the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a wear-resistant multidimensional micro-nanostructure super-hydrophobic coating, characterized in that: The following steps are involved: Step 1. Mix and disperse the primer raw materials evenly and spray them on the surface of the substrate; Step 2. Mix and disperse the topcoat raw materials evenly. After the primer coating is dry, spray the evenly mixed and dispersed topcoat raw materials on the primer and cure at room temperature. The primer raw materials include: 20% vinyl resin, 14% to 20% silicone resin, 15% to 35% inorganic filler, and the balance solvent A1, curing agent and additives, calculated by weight percentage; The inorganic filler includes an inorganic filler B1 and an inorganic filler B2, wherein the inorganic filler B1 is hollow glass microspheres with a particle size of 20 to 50 μm, and the inorganic filler B2 is hollow glass microspheres with a particle size of 100 to 150 μm; The topcoat and primer of the wear-resistant multi-dimensional micro-nanostructure super-hydrophobic coating are mutually inlaid structures, and the topcoat and primer form a multi-level rough structure from large micron structure C1, micron structure C2 to nanostructure C3; The distance between the mastoids of the large microstructure C1 is 50-150 μm, the distance between the mastoids of the microstructure C2 is 1-5 μm, and the distance between the particles of the nanostructure C3 is 10-1000 nm. The topcoat raw materials include: 10-20% silicone resin, 30-50% super-hydrophobic modified nano-silica, 2-4% organotin catalyst and the balance solvent, calculated by weight percentage; the super-hydrophobic modified nano-silica contains particles of at least two particle sizes.

2. The method for preparing a wear-resistant multidimensional micro-nanostructure super-hydrophobic coating according to claim 1, wherein The inorganic filler comprises: 5% to 10% of inorganic filler B1 and 10% to 25% of inorganic filler B2, calculated by weight percentage.

3. The method for preparing a wear-resistant multidimensional micro-nanostructure super-hydrophobic coating according to claim 1, wherein The particle size of the nano-silicon dioxide is 10-1000 nm.

4. The method for preparing a wear-resistant multidimensional micro-nanostructure super-hydrophobic coating according to claim 1, wherein The topcoat raw materials include: 15-20% silicone resin, 30-50% super-hydrophobic modified nano-silica, 2-4% organotin catalyst and the balance solvent, calculated by weight percentage.

5. The method for preparing a wear-resistant multidimensional micro-nanostructure super-hydrophobic coating according to claim 1, wherein The preparation method of the super-hydrophobic modified nano-silica comprises: An alcohol solvent, an alkaline catalyst, and a silicate are sequentially added to a reactor, the temperature is raised to 60±10°C and then maintained constant, the reaction is divided into two parts, and the reaction is carried out for 24 hours and 72 hours respectively. After filtration and drying, unmodified nano-silica of two particle sizes is obtained; the dried nano-silica of two particle sizes is mixed with an alcohol solvent and an ester solvent, and polysiloxane with a molecular weight between 500 and 5w is added, and the reaction is carried out at 80±5°C for 5±0.5 hours to obtain super-hydrophobic modified nano-silica containing particles of two particle sizes.

6. A wear-resistant multi-dimensional micro-nanostructure super-hydrophobic coating, characterized in that: It includes a primer coated on the surface of a substrate and a topcoat attached to the primer; the preparation process of the wear-resistant multidimensional micro-nanostructure super-hydrophobic coating includes the preparation method of the wear-resistant multidimensional micro-nanostructure super-hydrophobic coating according to any one of claims 1 to 5.

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