A super-hydrophobic anti-icing coating and preparation method thereof

Abstract

The present invention discloses a super-hydrophobic anti-icing coating and a preparation method thereof, which relates to the technical field of hydrophobic coatings. The method comprises the following steps: flattening and fixing a lotus leaf, then mixing PDMS A and B glue and pouring the mixture on the lotus leaf, removing bubbles, heating and curing, and obtaining a PDMS template with a papillary structure on the lotus leaf surface; spraying a ZIF-8 nanoparticle dispersion onto the PDMS template; evenly mixing epoxy resin and a curing agent, removing bubbles, evenly applying the mixture on a substrate, heating and curing until semi-dry, and then placing the PDMS template on the epoxy resin coating, curing at room temperature, and peeling off the PDMS template to obtain a super-hydrophobic anti-icing coating. The present invention also discloses a super-hydrophobic anti-icing coating prepared by the above method. The method replicates the hydrophobic structure on the surface of the lotus leaf to the surface of the material by a template etching method, greatly improving the hydrophobic anti-icing performance of the coating, helping to reduce corrosion and damage to the material, and having great application value.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrophobic coatings, and in particular to a super-hydrophobic anti-icing coating and a preparation method thereof. Background Art

[0002] Material corrosion is an irreversible natural phenomenon and has become a major threat to global industrial development. Improving the corrosion resistance of materials is urgent. Traditional deicing methods, such as heating, salting, and deicing agents, often consume large amounts of energy or cause serious pollution to soil, water sources, and vegetation. Superhydrophobic coatings, due to their exceptionally water-repellent properties, have attracted numerous researchers and provided innovative insights into surface deicing and corrosion resistance.

[0003] Superhydrophobic anti-icing coatings can reduce the adhesion of ice to surfaces, making it easier for the ice to fall off naturally or be removed with minimal force. This reduces reliance on energy-intensive de-icing methods, thereby reducing energy consumption, greenhouse gas emissions, and negative environmental impacts associated with energy production. Furthermore, hydrophobic anti-icing coatings physically prevent ice formation and adhesion, eliminating the risk of chemical contamination.

[0004] In recent years, due to the high instability of the hierarchical roughness and low surface energy components on the surface of super-hydrophobic materials, they are easily destroyed by slight shear forces, causing the materials to lose their super-hydrophobicity, reducing their service life and value. This has become the most prominent problem hindering the practical application of super-hydrophobic materials and is therefore in urgent need of resolution. Although some researchers have proposed methods such as adding adhesive layers and repair agents to extend the service life of super-hydrophobic materials, these studies have only remained at the two-dimensional level and have certain limitations in their thinking. Therefore, they have not yet been able to effectively resolve the existing problems. Summary of the Invention

[0005] In order to solve the above technical problems, the purpose of the present invention is to provide a super hydrophobic anti-icing coating and a preparation method thereof. This method uses a template etching method to copy the hydrophobic structure of the lotus leaf surface to the material surface, which greatly improves the hydrophobic and anti-icing properties of the coating, helps to reduce corrosion and damage of the material, and has great application value.

[0006] The present invention solves the above technical problems with the following technical solution: a method for preparing a super-hydrophobic anti-icing coating is provided, comprising the following steps:

[0007] (1) The lotus leaf is flattened and fixed, and then PDMS glue A and PDMS glue B are evenly mixed and poured on the lotus leaf. Air bubbles are removed by vacuum degassing, and the mixture is cured at room temperature. Finally, the mixture is peeled off from the lotus leaf to obtain a PDMS template with the papillary structure of the lotus leaf surface;

[0008] (2) Dispersing ZIF-8 nanoparticles in ethyl acetate and then evenly spraying them onto the side of the PDMS template with the papillary structure;

[0009] (3) The epoxy resin and the curing agent are mixed evenly, and bubbles are removed by vacuum degassing. Then, the epoxy resin is evenly applied on the substrate and heated to be cured until semi-dry. Then, the PDMS template treated in step (2) is placed on the epoxy resin coating, and the side with the papillary structure is close to the epoxy resin coating. Finally, the epoxy resin coating is cured at room temperature, and the PDMS template is removed to obtain a superhydrophobic anti-icing coating.

[0010] Furthermore, in step (1), the volume ratio of PDMS glue A to PDMS glue B is 1:0.8-1.2, wherein PDMS glue A is a PDMS prepolymer and PDMS glue B is a curing agent.

[0011] Furthermore, in step (1), curing is carried out at room temperature for 12-24 hours.

[0012] Furthermore, in step (2), ZIF-8 nanoparticles are prepared by the following method: zinc nitrate, 2-methylimidazole and water are mixed evenly, allowed to react for 24 hours, and then centrifuged, washed and dried to obtain ZIF-8 nanoparticles.

[0013] Furthermore, in step (2), the mass ratio of ZIF-8 nanoparticles to ethyl acetate is 0.6-1.4:1.

[0014] Furthermore, in step (3), the mass ratio of epoxy resin to curing agent is 2-4:1.

[0015] Furthermore, in step (3), the curing agent is polyetheramine D230.

[0016] Furthermore, in step (3), the coating thickness is 0.8-1.2 mm; and the substrate is a carbon fiber sheet.

[0017] Furthermore, in step (3), the mixture is heated to 45-80° C. and cured for 10-45 minutes until semi-dry; and cured at room temperature for 20-30 hours.

[0018] The method of the present invention first allows PDMS (polydimethylsiloxane) to solidify on the surface of a lotus leaf, and the papillary structure on the lotus leaf surface is copied to serve as a template; then a ZIF-8 nanoparticle dispersion is evenly sprayed on the PDMS template, thereby embedding the super-hydrophobic ZIF-8 nanoparticles into the papillary structure of the PDMS template; then the PDMS template is placed on an epoxy resin coating, the epoxy resin is cured, and the lotus leaf papillary structure and super-hydrophobic ZIF-8 nanoparticles on the PDMS template are copied onto the epoxy resin to prepare a super-hydrophobic anti-icing coating. The super-hydrophobic coating is a coating composed of a mixed solution of epoxy resin and polyetheramine D230, ZIF-8 nanoparticles, and the papillary structure.

[0019] The present invention also provides a super-hydrophobic anti-icing coating prepared by the above-mentioned preparation method of the super-hydrophobic anti-icing coating.

[0020] The present invention has the following beneficial effects:

[0021] 1. The method of the present invention adopts a template etching method to skillfully etch the hydrophobic structure on the surface of the lotus leaf, and sprays a super-hydrophobic coating ZIF-8 to further prepare a coating with a super-hydrophobic composite surface, so that the surface of the material has a super-hydrophobic and anti-icing effect.

[0022] 2. The water contact angle of the super-hydrophobic anti-icing coating prepared by the method of the present invention is significantly increased, and the freezing time is also prolonged. After freezing, the ice layer mainly exists in the form of frost ice with a loose structure. The frost ice with this structure has a weak bonding force with the base material and is easily carried away by wind at a certain wind speed. The greater the wind speed, the more conducive it is to the occurrence of ice shedding, thereby having a beneficial effect on reducing the weight of the sample.

[0023] 3. The present invention forms a microscopic or nanoscale structure on the surface, so that water droplets form a high contact angle when contacting the surface, thereby achieving the effect of rapid rolling of water droplets and difficulty in forming ice crystals on the surface, thereby achieving the purpose of super-hydrophobic anti-icing. The research and development of the present invention not only helps to improve the performance of drones in low temperature and high humidity environments, but also reduces the additional energy consumption and maintenance costs caused by icing. It not only significantly improves the performance of drones in harsh climatic conditions, but also provides new ideas for the design and maintenance of drones. The advancement of this technology also provides reference for anti-icing research in other fields, including aerospace, ocean exploration, and transportation, showing its cross-domain application prospects.

[0024] 4. The super-hydrophobic anti-icing coating of the present invention can make the substrate surface waterproof and anti-icing, thereby reducing corrosion and damage, extending the service life of infrastructure, and reducing maintenance frequency. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram of fixing the lotus leaf in Example 1;

[0026] Figure 2 Schematic diagram of the PDMS template in Example 1;

[0027] Figure 3 This is a schematic diagram of the operation of step (3) in Example 1;

[0028] Figure 4 Schematic diagram of the structure of the super-hydrophobic anti-icing coating prepared in Example 1;

[0029] Figure 5 Schematic diagram of the coating structure prepared in Comparative Example 1;

[0030] Figure 6 This is an electron microscope image of the super-hydrophobic anti-icing coating prepared in Example 1;

[0031] Figure 7 The electron microscope images of the coatings prepared in Example 1 and Comparative Example 1 are shown;

[0032] Figure 8 This is the surface energy spectrum of the super-hydrophobic anti-icing coating prepared in Example 1;

[0033] Figure 9 Graph showing the contact angle test results of the super-hydrophobic anti-icing coating prepared in Example 1;

[0034] Figure 10 This is a contact angle test result diagram of the coating prepared in Comparative Example 1;

[0035] Figure 11 This is a comparison chart of the icing of the original plate and the super-hydrophobic anti-icing coating prepared in Example 1. DETAILED DESCRIPTION

[0036] The principles and features of the present invention are described below. The examples are intended only to illustrate the present invention and are not intended to limit the scope of the present invention. In the examples, where specific conditions are not specified, conventional conditions or manufacturer-recommended conditions were used. Reagents or instruments used where the manufacturer is not specified are conventional products that can be purchased commercially.

[0037] Example 1

[0038] A super-hydrophobic anti-icing coating, the preparation method of which comprises the following steps:

[0039] (1) Figure 1 As shown in the figure, the lotus leaf was flattened and fixed, and then PDMS glue A and PDMS glue B were mixed evenly in a volume ratio of 1:1 and poured on the lotus leaf. The bubbles were removed by vacuum degassing and the mixture was cured at room temperature for 20 hours. Finally, it was peeled off from the lotus leaf to obtain a PDMS template with the papillary structure of the lotus leaf surface (as shown in the figure). Figure 2 shown);

[0040] (2) Dispersing ZIF-8 nanoparticles in ethyl acetate at a mass ratio of 1:1, and then evenly spraying them onto the side of the PDMS template with the papillary structure;

[0041] (3) Epoxy resin and polyetheramine D230 were mixed in a mass ratio of 3:1, and air bubbles were removed by vacuum degassing. Then, the mixture was evenly applied on the substrate (carbon fiber sheet) with a thickness of 1 mm. The mixture was heated to 60 °C and cured for 30 min until semi-dry. The PDMS template treated in step (2) was then placed on the epoxy resin coating (e.g. Figure 3 As shown), and the side with the papillary structure is placed close to the epoxy resin coating, and finally cured at room temperature for 24 hours, the PDMS template is removed to obtain a super hydrophobic anti-icing coating (as shown). Figure 4 shown).

[0042] Example 2

[0043] A super-hydrophobic anti-icing coating, the preparation method of which comprises the following steps:

[0044] (1) The lotus leaf was flattened and fixed, and then PDMS glue A and PDMS glue B were mixed evenly in a volume ratio of 1:0.8 and poured onto the lotus leaf. The bubbles were removed by vacuum degassing, and the mixture was cured at room temperature for 12 h. Finally, the mixture was peeled off from the lotus leaf to obtain a PDMS template with the papillary structure of the lotus leaf surface.

[0045] (2) Dispersing ZIF-8 nanoparticles in ethyl acetate at a mass ratio of 0.6:1, and then evenly spraying them onto the side of the PDMS template with the papillary structure;

[0046] (3) Epoxy resin and polyetheramine D230 were mixed evenly in a mass ratio of 2:1, and bubbles were removed by vacuum degassing. Then, the mixture was evenly applied on the substrate (carbon fiber plate) with a coating thickness of 0.8 mm. The mixture was heated to 45°C and cured for 45 minutes until semi-dry. The PDMS template treated in step (2) was then placed on the epoxy resin coating, with the side with the papillary structure close to the epoxy resin coating. Finally, the mixture was cured at room temperature for 20 hours, and the PDMS template was removed to obtain a superhydrophobic anti-icing coating.

[0047] Example 3

[0048] A super-hydrophobic anti-icing coating, the preparation method of which comprises the following steps:

[0049] (1) The lotus leaf was flattened and fixed, and then PDMS glue A and PDMS glue B were mixed evenly in a volume ratio of 1:1.2 and poured onto the lotus leaf. The bubbles were removed by vacuum degassing, and the mixture was cured at room temperature for 24 h. Finally, the mixture was peeled off from the lotus leaf to obtain a PDMS template with the papillary structure of the lotus leaf surface.

[0050] (2) Dispersing ZIF-8 nanoparticles in ethyl acetate at a mass ratio of 1.4:1, and then evenly spraying them onto the side of the PDMS template with the papillary structure;

[0051] (3) Epoxy resin and polyetheramine D230 were mixed evenly in a mass ratio of 4:1, and bubbles were removed by vacuum degassing. Then, the mixture was evenly applied on the substrate (carbon fiber plate) with a coating thickness of 1.2 mm. The mixture was heated to 80°C and cured for 10 min until semi-dry. The PDMS template treated in step (2) was then placed on the epoxy resin coating, with the side with the papillary structure close to the epoxy resin coating. Finally, the mixture was cured at room temperature for 30 h, and the PDMS template was removed to obtain a superhydrophobic anti-icing coating.

[0052] Comparative Example 1

[0053] A coating, the preparation method of which comprises the following steps:

[0054] (1) PDMS glue A and PDMS glue B were mixed in a volume ratio of 1:1 and poured into the mold. The bubbles were removed by vacuum degassing and cured at room temperature for 20 h to obtain a PDMS template.

[0055] (2) Disperse ZIF-8 nanoparticles in ethyl acetate at a mass ratio of 1:1 and then evenly spray them onto the PDMS template;

[0056] (3) Epoxy resin and polyetheramine D230 were mixed uniformly in a mass ratio of 3:1, and air bubbles were removed by vacuum degassing. Then, the mixture was evenly applied to the substrate (carbon fiber sheet) with a coating thickness of 1 mm. The mixture was heated to 60°C and cured for 30 min until semi-dry. The PDMS template treated in step (2) was then placed on the epoxy resin coating, with the side having ZIF-8 nanoparticles close to the epoxy resin coating. Finally, the mixture was cured at room temperature for 24 h, and the PDMS template was removed to obtain a coating (such as Figure 5 shown).

[0057] Test Example 1

[0058] (1) The coatings obtained in Example 1 and Comparative Example 1 are shown in the electron microscope images. Figure 6 and Figure 7 The results show that the super-hydrophobic anti-icing coating prepared by the method of the present invention has a papillary structure similar to the surface of a lotus leaf.

[0059] (2) The surface energy spectrum of the super hydrophobic anti-icing coating prepared in Example 1 is as follows Figure 8 The results show that C, O, and Zn elements are evenly distributed, indicating that ZIF-8 nanoparticles are successfully transferred to the surface of the epoxy coating and are evenly distributed.

[0060] (3) The contact angle test results of the coatings obtained in Example 1 and Comparative Example 1 are as follows: Figure 9 and Figure 10 The results show that the water contact angle of the coating prepared in Example 1 (158°) is significantly greater than that of Comparative Example 1 (111°), indicating that the papillary structure on the surface of the superhydrophobic anti-icing coating is beneficial to the hydrophobic property of the coating.

[0061] (4) The carbon fiber plate as is and the super-hydrophobic anti-icing coating prepared in Example 1 were placed on a cold platform for an icing experiment. The results are as follows: Figure 11 The results show that at -10°C, the freezing time of the original sample was 107 seconds, while the freezing time of the coating in Example 1 reached 3552 seconds, an increase of 3659 seconds. Furthermore, the ice layer on the surface of the coating in Example 1 was primarily frost ice with a loose structure. This frost ice structure has a weak bond with the base material and is more likely to fall off.

[0062] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements or improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for preparing a super-hydrophobic anti-icing coating, characterized in that: The following steps are involved: (1) Flatten and fix the lotus leaf, then mix PDMS glue A and PDMS glue B evenly and pour them on the lotus leaf. Remove bubbles by vacuum degassing, solidify at room temperature, and finally peel off from the lotus leaf to obtain a PDMS template with the papillary structure of the lotus leaf surface. (2) Dispersing ZIF-8 nanoparticles in ethyl acetate and then evenly spraying them onto the side of the PDMS template with the papillary structure; the mass ratio of the ZIF-8 nanoparticles to ethyl acetate is 0.6-1.4:1; (3) The epoxy resin and the curing agent are mixed evenly, and bubbles are removed by vacuum degassing. Then, the epoxy resin and the curing agent are evenly applied on the substrate and heated to be cured until semi-dry. Then, the PDMS template treated in step (2) is placed on the epoxy resin coating, and the side with the papillary structure is close to the epoxy resin coating. Finally, the epoxy resin is cured at room temperature, and the PDMS template is removed to obtain a super-hydrophobic anti-icing coating. The mass ratio of the epoxy resin to the curing agent is 2-4:

1. The curing agent is polyetheramine D230.

2. The method for preparing a super-hydrophobic anti-icing coating according to claim 1, wherein: In step (1), the volume ratio of the PDMSA glue to the PDMS B glue is 1:0.8-1.

2.

3. The method for preparing a super-hydrophobic anti-icing coating according to claim 1, wherein: In step (2), the ZIF-8 nanoparticles are prepared by the following method: zinc nitrate, 2-methylimidazole and water are mixed evenly, allowed to react for 24 hours, and then centrifuged, washed and dried to obtain ZIF-8 nanoparticles.

4. The method for preparing a super-hydrophobic anti-icing coating according to claim 1, wherein: In step (3), the coating thickness is 0.8-1.2 mm.

5. The method for preparing a super-hydrophobic anti-icing coating according to claim 1, wherein: In step (3), the substrate is a carbon fiber sheet.

6. The method for preparing a super-hydrophobic anti-icing coating according to claim 1, wherein: In step (3), heat to 45-80°C and cure for 10-45 minutes until semi-dry; cure at room temperature for 20-30 hours.

7. A super-hydrophobic anti-icing coating prepared by the method for preparing a super-hydrophobic anti-icing coating according to any one of claims 1 to 6.

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