Highly abrasion resistant transparent superhydrophobic icephobic coating with pyramid structure and method of making the same

Abstract

This application provides a highly wear-resistant, transparent, superhydrophobic, and anti-icing coating with a pyramid structure and its preparation method, relating to the field of superhydrophobic anti-icing technology. The method first prepares a transparent substrate with a pyramid structure array; after surface activation of the transparent substrate, a transparent adhesive resin dilution is coated and pre-cured by heating; subsequently, a hydrophobic particle dispersion is coated on the surface of the semi-cured film, causing the hydrophobic particles to mainly accumulate in the grooves between the pyramid protrusions, thus obtaining a composite coating. This application utilizes the pyramid array structure to disperse stress, improving mechanical wear resistance, and the combination of the pyramid structure and hydrophobic particles can significantly prolong the freezing time of water droplets in low-temperature environments and reduce ice adhesion. This application achieves superhydrophobicity while maintaining excellent optical transparency, and has broad application prospects in fields requiring both transparency and anti-icing functions, such as transparent aircraft components, photovoltaic modules, and outdoor optical devices.

Description

Technical Field

[0001] This application relates to the field of superhydrophobic anti-icing technology, and in particular to a highly wear-resistant transparent superhydrophobic anti-icing coating with a pyramid structure and its preparation method. Background Technology

[0002] Traditional active anti-icing technologies, such as electrothermal de-icing and hot gas de-icing, consume enormous amounts of energy. In contrast, superhydrophobic surfaces have attracted significant attention in passive anti-icing technologies due to their ability to significantly delay icing and reduce ice adhesion. The achievement of superhydrophobic properties typically relies on low surface energy chemicals and micro / nano-hierarchical rough structures on the surface, thereby significantly reducing droplet adhesion and ice adhesion strength. This approach is considered a highly promising passive anti-icing technology.

[0003] In existing technologies, superhydrophobic self-cleaning functions are achieved by constructing nano-rough structures through methods such as spraying, sol-gel, self-assembly, or particle stacking. For example, patent application CN 109971231A discloses a method for preparing superhydrophobic, corrosion-resistant, self-assembled three-dimensional nanomaterials. This method first prepares dahlia-shaped carbon nanohorns using an arc discharge method, and then performs a transient oxidation treatment to obtain open-pore carbon nanohorn materials. Then, after thoroughly mixing the carbon nanohorn materials with a zinc nano-ethanol slurry, a supercritical fluid method is used to self-assemble the carbon nanohorns and zinc nanohorns into a three-dimensional superhydrophobic pearl-like structure. However, the material preparation process in this method is very complex and difficult to meet the requirements of industrial-scale production; moreover, the structure of the prepared material surface is directly exposed, and under friction, impact, wind and sand erosion, or freeze-thaw cycles, structural collapse and damage easily occur, causing the surface to change from a Cassie state to a Wenzel state, resulting in a rapid decline in hydrophobic properties, which is difficult to meet the needs of long-term applications.

[0004] In addition to its primary function, for applications such as optical devices, displays, protective covers, and solar panels, coatings must simultaneously meet the requirements of high light transmittance and anti-icing properties. However, traditional superhydrophobic structures often employ randomly stacked micro / nano particles or large-scale rough structures, which easily cause light scattering and interface reflection, thereby reducing light transmittance. Excessively large or unevenly distributed microstructures can lead to a significant increase in haze; conversely, if nanoparticles are uniformly exposed on the surface, differences in refractive index can also enhance scattering. Therefore, achieving high transparency while maintaining superhydrophobic properties is a significant technical challenge currently facing transparent anti-icing coatings. Research on such surfaces and their preparation methods has important scientific significance and practical application value. Summary of the Invention

[0005] To address the shortcomings of the existing technology, the purpose of this application is to provide a highly wear-resistant, transparent, superhydrophobic, and anti-icing coating with a pyramidal structure and its preparation method. This highly wear-resistant, transparent, superhydrophobic, and anti-icing coating achieves both high transparency and mechanical durability while maintaining superhydrophobic properties, and has broad application prospects.

[0006] Specifically, the method first prepares an inverted pyramid array template using laser engraving technology, then casts the template using a transparent flexible substrate material and demolds it to obtain a transparent substrate with a pyramid structure array; the substrate is then surface-activated, coated with a transparent adhesive resin diluent and pre-cured by heating; subsequently, a hydrophobic particle dispersion is coated on the surface of the semi-cured film, so that the hydrophobic particles are mainly concentrated in the grooves between the pyramid protrusions, and then gradient heating is performed for curing to obtain a fully cured transparent superhydrophobic anti-icing composite film.

[0007] To achieve the above-mentioned objectives, this application provides a method for preparing a highly wear-resistant, transparent, superhydrophobic, and anti-icing coating with a pyramidal structure, comprising the following steps: S1. Laser engrave an inverted pyramid array on a rigid substrate as a template, pour a flexible polymer prepolymer onto the template, and demold after curing to obtain a transparent flexible substrate with a pyramid microstructure. S2. Surface activation treatment is performed on the transparent flexible substrate with pyramid microstructure obtained in step S1; then, resin dilution is uniformly coated on the surface of the transparent flexible substrate for pre-curing to form an incompletely cured resin adhesive layer. S3. Add a dispersant and a surfactant to the suspension containing hydrophobic nanoparticles, and sonicate to obtain a mixture; then, coat the mixture onto the surface of the semi-cured resin adhesive layer obtained in step S2, so that the hydrophobic nanoparticles are enriched in the valley grooves between the pyramid protrusions; then perform gradient temperature curing to obtain a fully cured transparent superhydrophobic anti-icing composite film.

[0008] Furthermore, in step S1, the rigid substrate is a silicon wafer, quartz glass, or a metal plate, and the laser engraving process is ultraviolet laser etching, femtosecond laser etching, or photolithography with humidification etching.

[0009] Furthermore, in step S2, the surface activation treatment method is one of oxygen plasma treatment or ultraviolet irradiation.

[0010] Furthermore, in step S3, the surfactant is polyether-modified polydimethylsiloxane.

[0011] Furthermore, in step S3, the coating method of the mixture is either spraying or dipping.

[0012] This application also provides a highly wear-resistant, transparent, superhydrophobic, and anti-icing coating with a pyramid structure, which is prepared by the preparation method described in any of the foregoing technical solutions; the highly wear-resistant, transparent, superhydrophobic, and anti-icing coating with a pyramid structure includes a flexible transparent substrate with a pyramid-shaped structure array, a transparent adhesive resin layer covering the surface of the flexible transparent substrate, and hydrophobic nanoparticles filling the grooves between adjacent pyramid-shaped structures.

[0013] Furthermore, the base of the pyramid-shaped structure has a side length of 5~10μm, a height of 3~8μm, and a distance of 1~3μm between the centers of adjacent protrusions.

[0014] Furthermore, the material of the flexible transparent substrate is either polydimethylsiloxane or a transparent polyurethane elastomer.

[0015] Furthermore, the transparent adhesive resin layer is made of epoxy resin or polyurethane acrylate resin, and the thickness of the transparent adhesive resin layer is 50~300 nm.

[0016] Furthermore, the hydrophobic nanoparticles have a particle size of 5-100 nm; the hydrophobic nanoparticles are one of silicon dioxide, zinc oxide, or titanium dioxide nanoparticles.

[0017] The beneficial effects of this application are: (1) The combination of the pyramid structure and the flexible substrate material in this application gives it excellent mechanical durability. The pyramid structure has inclined sides and a sharp apex. On the one hand, when subjected to normal load or tangential friction, the external force first acts on the apex of the pyramid protrusion. Moreover, the pyramid has a conical geometry, and the contact stress is rapidly dispersed along the inclined surface, which can effectively avoid microstructure collapse caused by local stress overload. On the other hand, the pyramid array transforms the continuous solid-solid contact interface into discrete point-to-surface contact. In the friction process, it actually only contacts the apex region of the pyramid, so that the wear is limited to the local area of ​​the apex, thereby greatly improving the service life of the coating. At the same time, the substrate uses a flexible material, which has a low elastic modulus and can undergo reversible elastic deformation when subjected to friction or impact. When the external force acts on the surface pyramid protrusion, the flexible substrate absorbs part of the mechanical energy through local deformation, transforming the concentrated load into dispersed strain energy. This stress buffering effect avoids brittle failure and allows the microstructure to maintain geometric integrity under repeated friction.

[0018] Furthermore, the flexible substrate used in this application forms a gradient modulus structure with the adhesive resin layer and the nanoparticle layer. This design effectively releases the shear stress generated by friction at the interface and avoids interface delamination caused by sudden changes in modulus.

[0019] (2) Through ingenious structural design and process control, this application enables the composite membrane to maintain its hydrophobic function for a long time, solving the core problem of "easy functional decay and short lifespan" of traditional superhydrophobic surfaces.

[0020] First, the spatial configuration of the pyramid structure gives it a unique physical shielding effect. When the surface is subjected to friction, scratching or impact, the pyramid protrusions act as "mechanical armor" to preferentially bear the external force, while the nanoparticles located in the grooves are physically protected by the surrounding protrusions and are always in the weakest area. Even if the top of the protrusions wears down to a certain extent during long-term use, the particles in the grooves are still protected by the residual structure and continue to perform hydrophobic functions.

[0021] Secondly, during long-term use, as the raised parts gradually wear down due to friction, the particles originally located deep in the grooves are gradually exposed to the surface, taking over from the worn particles to continue providing nanoscale roughness and low surface energy. Simultaneously, the introduction of a transparent adhesive resin layer strengthens the strong chemical bond and physical interlocking between the nanoparticles and the substrate. During the preparation process, nanoparticles are coated onto the surface of the semi-cured resin layer, with some particles embedded in the resin surface. In the final curing stage, the resin is fully cross-linked, firmly encapsulating and anchoring the nanoparticles. This anchoring mechanism makes it difficult for the nanoparticles to detach from the surface under mechanical forces, thus maintaining the surface's hydrophobicity over a long period.

[0022] (3) This application achieves superhydrophobicity while maintaining excellent optical transparency. By controlling the coating process, hydrophobic nanoparticles are selectively concentrated in the valley recesses between the pyramidal protrusions, rather than uniformly covering the entire surface. This avoids the accumulation of nanoparticles in key areas of the light propagation path, minimizing scattering loss. Furthermore, the discontinuous distribution of particles avoids agglomeration, as aggregated nanoparticles would act as strong scattering centers, leading to a significant increase in haze. In this application, there is no multilayer accumulation of particles within the pyramidal recesses, further suppressing scattering.

[0023] Furthermore, by selecting suitable materials—namely, the transparent bonding resin layer (such as epoxy resin, with a refractive index adjustable to 1.45~1.50), the transparent substrate material (such as polydimethylsiloxane, with a refractive index of approximately 1.43), and the silica nanoparticles (with a refractive index of approximately 1.46)—which have similar refractive indices, Fresnel reflection at the interface is significantly reduced, minimizing the impact of interface reflection on light transmittance. Simultaneously, by using spin-coating or wire-bar coating processes, the film thickness of the bonding resin layer can be precisely controlled, ensuring the anchoring of the nanoparticles while maintaining a thin film thickness that does not affect light transmittance.

[0024] (4) The method for preparing the high wear-resistant transparent superhydrophobic anti-icing coating with a pyramid structure provided in this application is simple and easy to implement, has low preparation cost, and is suitable for large-area preparation. It can maintain superhydrophobic and anti-icing functions when coated on any substrate, has a wide range of applications, and can meet the needs of actual production and application. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of a highly wear-resistant, transparent, superhydrophobic, and anti-icing coating with a pyramid structure.

[0026] Figure 2 This is a scanning electron microscope (SEM) image of the pure PDMS substrate with a pyramidal structure prepared in Example 1.

[0027] Figure 3 This is a scanning electron microscope (SEM) image of the PDMS substrate coated with hydrophobic silica particles in Example 1.

[0028] Figure 4 A schematic diagram illustrating the wear resistance mechanism of the high wear-resistant and anti-icing coating with a pyramid structure provided in this application.

[0029] Figure 5 Visual comparison photos of the high transparency of the highly wear-resistant, transparent, superhydrophobic, and anti-icing coating prepared for this application. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of this application clearer, the application will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0031] It should also be noted that, in order to avoid obscuring this application with unnecessary details, only the structures and / or processing steps closely related to the solution of this application are shown in the accompanying drawings, while other details that are not closely related to this application are omitted.

[0032] Additionally, it should be noted that the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0033] This application provides a method for preparing a highly wear-resistant, transparent, superhydrophobic, and anti-icing coating with a pyramidal structure, comprising the following steps: S1. Laser engrave an inverted pyramid array on a rigid substrate as a template, pour a flexible polymer prepolymer onto the template, and demold after curing to obtain a transparent flexible substrate with a pyramid microstructure. The rigid substrate is a silicon wafer, quartz glass, or metal plate.

[0034] Laser engraving can be performed using ultraviolet laser etching, femtosecond laser etching, or photolithography with humidification.

[0035] S2. Surface activation treatment is performed on the transparent flexible substrate with pyramid microstructure obtained in step S1. The prepared resin dilution is uniformly coated on the surface of the transparent flexible substrate and pre-cured to form an incompletely cured resin bonding layer. Among them, the surface activation treatment method is one of oxygen plasma treatment or ultraviolet irradiation.

[0036] The coating method for the resin diluent is one of spin coating, wire rod coating, or dip coating.

[0037] S3. Dilute the suspension containing hydrophobic nanoparticles and add dispersant and surfactant, then sonicate to obtain a mixture; subsequently, coat the mixture onto the surface of the semi-cured resin adhesive layer obtained in step S2, so that the hydrophobic nanoparticles are enriched in the valley grooves between the pyramid protrusions, and then perform gradient temperature curing to obtain a fully cured transparent superhydrophobic anti-icing composite film.

[0038] The surfactant is polyether-modified polydimethylsiloxane.

[0039] The coating method for the mixture is either spraying or dipping.

[0040] This application also provides a highly wear-resistant, transparent, superhydrophobic, and anti-icing coating with a pyramid structure, which is prepared by the aforementioned method; the highly wear-resistant, transparent, superhydrophobic, and anti-icing coating with a pyramid structure includes a flexible transparent substrate with an array of pyramid-shaped structures, a transparent adhesive resin layer covering the surface of the flexible transparent substrate, and hydrophobic nanoparticles filling the grooves between adjacent pyramid-shaped structures.

[0041] The base of the pyramid-shaped structure has a side length of 5-10 μm, a height of 3-8 μm, and a distance of 1-3 μm between adjacent protrusion centers.

[0042] The flexible transparent substrate is made of polydimethylsiloxane or transparent polyurethane elastomer.

[0043] The transparent adhesive resin layer is made of epoxy resin or polyurethane acrylate resin, and its thickness is 50~300 nm.

[0044] The hydrophobic nanoparticles are one of silicon dioxide, zinc oxide, or titanium dioxide nanoparticles.

[0045] The hydrophobic nanoparticles have a particle size of 5~100 nm.

[0046] This application utilizes a micron-scale pyramid array structure to disperse stress and improve mechanical wear resistance. The combination of the pyramid structure and hydrophobic particles can significantly extend the freezing time of water droplets and reduce ice adhesion in low-temperature environments. Through uniform coating and surface energy regulation, nanoparticles can be densely distributed within the microstructure grooves, providing external structural protection and greatly enhancing the hydrophobic stability of the material. Furthermore, the resin layer effectively improves the chemical compatibility and mechanical adhesion between the upper hydrophobic functional coating and the lower substrate, maintaining good transparency of the coating. This application has broad prospects in fields requiring both transparency and anti-icing functions, such as transparent aircraft components, photovoltaic modules, and outdoor optical devices.

[0047] The following describes the high wear-resistant transparent superhydrophobic anti-icing coating with a pyramid structure and its preparation method provided in this application, with reference to specific embodiments.

[0048] Example 1 This embodiment provides a method for preparing a highly wear-resistant, transparent, superhydrophobic, and anti-icing coating with a pyramidal structure, comprising the following steps: S1. Preparation of a transparent flexible substrate with a pyramidal microstructure: Preparation of inverted pyramid template: An inverted pyramid array with a bottom side length of about 8 μm, a height of about 5 μm, and a spacing of about 2 μm between the centers of adjacent protrusions was engraved on a copper plate using an ultraviolet laser. After processing, the template was ultrasonically cleaned in sequence with acetone, ethanol, and deionized water.

[0049] Next, the Sylgard 184 PDMS prepolymer and curing agent were mixed at a mass ratio of 10:1, stirred evenly, and then placed in a vacuum drying oven for vacuum degassing. The mixture was then slowly poured onto a copper template, ensuring it evenly covered the surface of the template, and placed in an 80°C oven for curing. After the polymer cooled, it was peeled off from the copper plate with tweezers, yielding a fully cured, transparent, flexible substrate with a pyramidal surface structure.

[0050] S2, Coating with resin layer: Preparation before coating: First, mix two-component epoxy resin (E51 epoxy resin and polyamide curing agent, mass ratio 2:1) with acetone at a mass ratio of 3:1, and stir magnetically to obtain a uniform and transparent epoxy resin dilution.

[0051] During resin stirring, the PDMS film (a transparent flexible substrate with a pyramidal structure on its surface) prepared in step S1 is placed under a xenon lamp for ultraviolet irradiation at a distance of 15 cm from the light source for 40 min. The sample is rotated 90° every 10 min to ensure uniform irradiation, thus obtaining a surface-activated PDMS film.

[0052] Resin layer coating is performed within 10 minutes after activation: The film is laid flat and fixed on a glass plate with the side having the pyramidal microstructure facing upwards. An appropriate amount of epoxy resin dilution is dropped onto one end of the substrate. Using a wire bar coater (model XB-5), the resin solution is pulled from one end to the other at a constant speed and uniform pressure to spread evenly across the entire surface. After coating, the sample is allowed to stand to allow the resin to level, and then transferred to a 60℃ oven for pre-curing to obtain a semi-cured epoxy resin surface layer.

[0053] S3, Coating with hydrophobic nanoparticle dispersion: Ethanol, isopropanol, and a surfactant were added to a certain mass of hydrophobic silica particle dispersion, wherein the mass ratio of hydrophobic silica stock solution: ethanol: isopropanol: surfactant = 150:150:25:1. The mixture was sealed and vortexed, then ultrasonically dispersed in an ultrasonic cleaner to obtain a uniform, stable, and semi-transparent dispersion. The pre-cured sample prepared in step S2 was then vertically immersed in the prepared hydrophobic silica particle dispersion using tweezers for 30 seconds, with gentle shaking to ensure full contact between the dispersion and the microstructure surface. After immersion, the sample was vertically removed from the dispersion at a constant speed, allowing excess liquid to drain naturally. The sample was then placed vertically in a fume hood to allow partial solvent evaporation, resulting in a hydrophobic multilayer composite film.

[0054] After standing, the samples were placed in a constant temperature oven for gradient curing: 50℃ for 30 min, 80℃ for 60 min, and 100℃ for 20 min.

[0055] In this embodiment, the hydrophobic silica nanoparticles have a particle size of 8 nm, and the surfactant is BYK-2155.

[0056] Through the above method, the highly wear-resistant, transparent, superhydrophobic coating with a pyramidal structure prepared in this embodiment exhibits excellent wear resistance and persistent hydrophobicity while maintaining high transparency. Its structure and preparation schematic diagram are shown below. Figure 1 As shown, specifically: the bottom layer of the highly wear-resistant transparent superhydrophobic coating is a PDMS flexible substrate with a pyramidal protrusion array, the middle layer is an epoxy resin adhesive layer, and the surface layer is hydrophobic modified silica nanoparticles. The nanoparticles are mainly concentrated in the valley groove area between the pyramidal protrusions, while the particle distribution is sparse at the top of the protrusions and on the sloping surface.

[0057] In this embodiment, the electron microscope image of the PDMS substrate with a pyramidal structure obtained in step S1 is shown below. Figure 2As shown, the pyramid structure prepared in this embodiment is regularly arranged and uniform in size, with a center-to-center distance of approximately 2 μm between adjacent protrusions, a base side length of approximately 8 μm, and a height of approximately 5 μm. The array coverage is complete, without defects or collapse. Furthermore, the pyramid edges are clear, the slopes are smooth, and the valley bottom groove structure is intact, fully demonstrating the precise replication capability of the PDMS substrate for the pyramid template.

[0058] Figure 3 This is a scanning electron microscope image of the PDMS substrate coated with hydrophobic silica particles in Example 1. It can be seen that the hydrophobic silica nanoparticles are mainly distributed in the valley recesses between the pyramidal protrusions, forming a high-density enrichment area; while the particle distribution is extremely sparse on the slopes and apex regions of the pyramidal protrusions. This selective distribution is the structural basis for realizing the design concept of "wear-resistant protrusions and particle-containing recesses".

[0059] Figure 4 A schematic diagram of the wear resistance mechanism of the high wear-resistant and anti-icing coating with a pyramid structure provided in this application. Figure a shows the wear resistance defects of traditional uniformly coated superhydrophobic surfaces. When the surface is subjected to frictional force (as shown by the arrow), the nanoparticles are uniformly and directly exposed to the friction interface, and are easily worn off under mechanical action, resulting in a rapid decline in superhydrophobic performance.

[0060] Figure b illustrates the wear-resistant mechanism of this application. When frictional forces act on the surface, the pyramidal protrusions, acting as "mechanical armor," preferentially bear the stress. Local wear occurs at the top of the protrusions, but the overall structure remains intact. The nanoparticles located in the valley are physically shielded and protected by the surrounding protrusions, remaining in a weak stress area and not easily worn off. Even if the top of the protrusions experiences some wear during long-term use, the particles stored in the valley can still continuously provide nano-roughness and low surface energy, giving the composite film long-lasting resistance to degradation of its superhydrophobic properties.

[0061] To demonstrate the high transparency of the composite coating prepared in this application, we conducted a visual comparison, and the results are as follows: Figure 5 As shown in the figures, the top image is the original paper printout without any film covering, and the bottom image is a photograph of the same paper printout after the composite film prepared in Example 1 of this application has been applied to its surface. It is clearly visible from the images that even after applying the composite film, the details of the text and patterns below remain clearly discernible. Furthermore, the visual difference between the covered and uncovered areas is minimal under naked-eye observation, indicating that the composite film of this application possesses excellent optical transparency in the visible light band and has minimal impact on the intrinsic transmittance of the substrate material. This fully demonstrates that the composite film of this application successfully maintains the high transparency characteristics of the substrate material while achieving multifunctional integration such as superhydrophobicity, wear resistance, and anti-icing, meeting the stringent transmittance requirements of applications such as aerospace transparent parts, photovoltaic glass, and optical windows.

[0062] Example 2 Compared to Example 1, the difference lies in the change of the dimensions of the pyramid structure in step S1. Specifically, the template is an inverted pyramid array with a base side length of approximately 5 μm, a height of approximately 3 μm, and a center-to-center distance between adjacent protrusions of approximately 1 μm. The remaining steps and parameters are the same as in Example 1 and will not be repeated here.

[0063] Example 3 Compared with Example 1, the difference lies in the change of the size of the pyramid structure in step S1. Specifically, the template is an inverted pyramid array with a base side length of approximately 10 μm, a height of approximately 8 μm, and a center-to-center distance between adjacent protrusions of approximately 3 μm. The remaining steps and parameters are the same as in Example 1, and will not be repeated here.

[0064] Testing showed that the samples prepared in Examples 2 and 3 both possessed highly wear-resistant, transparent, superhydrophobic, and anti-icing properties. The ranking of wear resistance among the examples was: Example 3 > Example 1 > Example 2; the ranking of light transmittance was: Example 2 > Example 1 > Example 3; and the ranking of surface hydrophobicity was: Example 1 > Example 3 > Example 2. This indicates that Example 1 achieved a better balance between transparency and wear resistance / hydrophobicity, exhibiting the best overall performance. This is mainly because larger pyramids have stronger mechanical stability and better protection for particles within the grooves. However, as the size increases, the adhesion of hydrophobic nanoparticles and light scattering are affected, leading to differences in transparency.

[0065] Therefore, while ensuring the sample has superhydrophobic properties, in order to achieve the best balance between wear resistance and transparency, this application preferably uses a pyramid-shaped structure with a base side length of 5~10 μm, a height of 3~8 μm, and a center-to-center distance between adjacent protrusions of 1~3 μm.

[0066] It should be noted that the above embodiments are only some of the examples listed.

[0067] Those skilled in the art will understand that, in step S1, the substrate material is not limited to polydimethylsiloxane, but can also be other transparent elastic substrates, such as transparent polyurethane elastomers. The rigid substrate used can be a silicon wafer, quartz glass, or a metal plate, and the processing method can be ultraviolet laser etching, femtosecond laser etching, or photolithography with wet etching.

[0068] Similarly, in step S2, the surface activation treatment method can be one of oxygen plasma treatment or ultraviolet irradiation. The transparent adhesive resin layer can be epoxy resin or polyurethane acrylate resin. The coating method can be one of spin coating, wire rod coating or dip coating, with a thickness of 50~300 nm.

[0069] In step S3, the selected hydrophobic nanoparticles can be one of silica, zinc oxide, or titanium dioxide nanoparticles, with a particle size of 5-100 nm. The dispersion coating method can be spraying or dipping, both of which can achieve high wear resistance, transparency, superhydrophobicity, and anti-icing function, and both fall within the protection scope of this application.

[0070] In summary, this application provides a highly wear-resistant, transparent, superhydrophobic, and anti-icing coating with a pyramid structure and its preparation method. This application involves preparing an inverted pyramid array template using laser engraving technology; casting the template using a transparent flexible substrate and demolding it to obtain a transparent substrate with a pyramid structure array; surface activation of the substrate; coating with a transparent adhesive resin diluent and pre-curing by heating; coating the surface of the semi-cured film with a hydrophobic particle dispersion, so that the hydrophobic particles are mainly concentrated in the pyramid grooves; and obtaining a composite film after gradient curing.

[0071] Through the above methods, this application can utilize the micron-level pyramid array structure to disperse stress and improve mechanical wear resistance; and through uniform coating and surface energy regulation, it can achieve dense distribution of nanoparticles in the microstructure grooves, so that they are protected by the external structure and greatly enhance the hydrophobic stability of the material; and the resin layer can effectively improve the chemical compatibility and mechanical adhesion between the upper hydrophobic functional coating and the lower substrate, so that the coating maintains good transparency and can achieve a wider range of applications. The above embodiments are only used to illustrate the technical solutions of this application and are not intended to limit it. Although this application has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of this application without departing from the spirit and scope of the technical solutions of this application.

Claims

1. A method for preparing a transparent superhydrophobic anti-icing coating with high abrasion resistance having a pyramid structure, characterized in that, Includes the following steps: S1. Laser engrave an inverted pyramid array on a rigid substrate as a template, pour a flexible polymer prepolymer onto the template, and demold after curing to obtain a transparent flexible substrate with a pyramid microstructure. S2. Surface activation treatment is performed on the transparent flexible substrate with pyramid microstructure obtained in step S1; then, resin dilution is uniformly coated on the surface of the transparent flexible substrate for pre-curing to form an incompletely cured resin adhesive layer. S3. Add a dispersant and a surfactant to the suspension containing hydrophobic nanoparticles, and sonicate to obtain a mixture; then, coat the mixture onto the surface of the semi-cured resin adhesive layer obtained in step S2, so that the hydrophobic nanoparticles are enriched in the valley bottom groove between the pyramid protrusions. Then, gradient heating and curing are performed to obtain a fully cured transparent superhydrophobic anti-icing composite film.

2. The method for preparing a transparent superhydrophobic anti-icing coating with high abrasion resistance and pyramid structure according to claim 1, characterized in that: In step S1, the rigid substrate is a silicon wafer, quartz glass, or a metal plate, and the laser engraving process is ultraviolet laser etching, femtosecond laser etching, or photolithography with humidification etching.

3. The method for preparing a transparent superhydrophobic anti-icing coating with high abrasion resistance and pyramid structure according to claim 1, characterized in that: In step S2, the surface activation treatment method is one of oxygen plasma treatment or ultraviolet irradiation.

4. The method of claim 1, wherein the method of preparing a transparent superhydrophobic anti-icing coating with high abrasion resistance in a pyramid structure is characterized by: In step S3, the surfactant is polyether-modified polydimethylsiloxane.

5. The method for preparing a highly wear-resistant, transparent, superhydrophobic, and anti-icing coating with a pyramidal structure according to claim 1, characterized in that: In step S3, the coating method for the mixture is either spraying or dipping.

6. A highly wear-resistant, transparent, superhydrophobic, and anti-icing coating with a pyramid structure, characterized in that: The coating is prepared according to the preparation method of any one of claims 1 to 5; the highly wear-resistant, transparent, superhydrophobic, and anti-icing coating with a pyramid structure comprises a flexible transparent substrate with an array of pyramid-shaped structures, a transparent adhesive resin layer covering the surface of the flexible transparent substrate, and hydrophobic nanoparticles filling the grooves between adjacent pyramid-shaped structures.

7. The highly wear-resistant, transparent, superhydrophobic, and anti-icing coating with a pyramid structure according to claim 6, characterized in that: The base of the pyramid-shaped structure has a side length of 5~10μm, a height of 3~8μm, and a distance of 1~3μm between the centers of adjacent protrusions.

8. The highly wear-resistant, transparent, superhydrophobic, and anti-icing coating with a pyramid structure according to claim 6, characterized in that: The flexible transparent substrate is made of either polydimethylsiloxane or a transparent polyurethane elastomer.

9. The highly wear-resistant, transparent, superhydrophobic, and anti-icing coating with a pyramid structure according to claim 6, characterized in that: The transparent adhesive resin layer is made of epoxy resin or polyurethane acrylate resin, and the thickness of the transparent adhesive resin layer is 50~300 nm.

10. The highly wear-resistant, transparent, superhydrophobic, and anti-icing coating with a pyramid structure according to claim 6, characterized in that: The hydrophobic nanoparticles have a particle size of 5-100 nm; the hydrophobic nanoparticles are one of silicon dioxide, zinc oxide, or titanium dioxide nanoparticles.

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