Spinel type composite photo-thermal super-hydrophobic coating, preparation method thereof and application thereof in ice prevention and removal

Abstract

The present application relates to the technical field of composite functional materials, in particular to a spinel-type composite photothermal super-hydrophobic coating, a preparation method thereof and application thereof in ice prevention and removal, wherein the preparation method of the spinel-type composite photothermal super-hydrophobic coating first prepares spinel-type CuFeMnO4 material with micro-nano structure through co-precipitation and high-temperature heat treatment of copper salt, iron salt and manganese salt, and then performs surface hydrophobic modification on the spinel-type CuFeMnO4 material by using palm wax. By combining the excellent photothermal conversion performance of the spinel-type CuFeMnO4 material with the low surface energy characteristics of palm wax, the synergistic effect of high-efficiency photothermal conversion and super-hydrophobic performance is realized, so that the coating layer formed by the prepared spinel-type composite photothermal super-hydrophobic coating has excellent super-hydrophobicity, durability and environmental adaptability and can achieve good ice prevention and removal effect. In addition, the preparation method has the advantages of simple process, low cost and environmental friendliness.

Description

Technical Field

[0001] This invention relates to the field of composite functional materials technology, specifically to a spinel-type composite photothermal superhydrophobic coating, its preparation method, and its application in anti-icing and de-icing. Background Technology

[0002] With the continuous development of science and technology, the demand for anti-icing, snowproofing, and anti-icing technologies is increasing in various fields, especially in aviation, power transmission, transportation facilities, and construction. The accumulation of frost not only affects the normal use of equipment and materials but can also pose safety hazards. For example, icing on aircraft wings can affect flight safety; ice on power lines can cause line breaks; and icing on transportation facilities can affect driving safety. Therefore, effectively preventing the adhesion and accumulation of frost and developing long-lasting, superhydrophobic anti-icing and de-icing materials has become one of the important research directions in the field of anti-icing technology.

[0003] Palm wax, a natural wax substance, has low surface energy and good hydrophobicity, and is widely used in the coating field. However, coatings made solely from palm wax, while possessing some hydrophobicity, exhibit poor durability, environmental adaptability, and anti-icing / de-icing performance. In order to better apply these coatings to anti-icing and de-icing in various fields, further research and development of high-performance anti-icing and de-icing composite materials is urgently needed. Summary of the Invention

[0004] To overcome the shortcomings of the prior art, the first objective of this invention is to provide a method for preparing a spinel-type composite photothermal superhydrophobic coating. This method has the advantages of simple process, economical cost and environmental friendliness. The obtained spinel-type composite photothermal superhydrophobic coating has excellent superhydrophobicity, durability and environmental adaptability, and can play a good role in anti-icing and de-icing.

[0005] To overcome the shortcomings of the prior art, the second objective of this invention is to provide a spinel-type composite photothermal superhydrophobic coating, which has excellent superhydrophobicity, durability and environmental adaptability, and can play a good role in anti-icing and de-icing.

[0006] The third objective of this invention is to provide an application of a spinel-type composite photothermal superhydrophobic coating in anti-icing and de-icing.

[0007] To achieve the first objective of the invention, the technical solution adopted by the present invention is as follows:

[0008] This invention provides a method for preparing a spinel-type composite photothermal superhydrophobic coating, comprising the following steps:

[0009] S1. Preparation of precursor: Dissolve copper salt, iron salt and manganese salt in water, add alkaline precipitant and mix, then add surfactant, after co-precipitation reaction, wash, centrifuge and dry to obtain metal hydroxide precipitate precursor;

[0010] S2. Preparation of spinel-type material: The metal hydroxide precipitate precursor is subjected to high-temperature heat treatment to obtain spinel-type CuFeMnO4 material;

[0011] Among them, the preparation process of the spinel-type CuFeMnO4 material with micro-nano structure is simple, the conditions are mild and controllable, the preparation cost is low, the material source is wide and the preparation efficiency is high, realizing the preparation of large batches of spinel-type CuFeMnO4 material with micro-nano structure.

[0012] S3. Surface hydrophobic modification: The spinel-type CuFeMnO4 material and palm wax are heated and melted in an organic solvent, and then cooled to obtain a composite photothermal hydrophobic material.

[0013] S4. Preparation of composite photothermal superhydrophobic coating: The composite photothermal hydrophobic material is added to epoxy resin and then ultrasonically dispersed to obtain the spinel-type composite photothermal superhydrophobic coating.

[0014] The present invention discloses a method for preparing a spinel-type composite photothermal superhydrophobic coating, which involves surface modification of a spinel-type CuFeMnO4 material with a micro-nano structure by palm wax, followed by uniform mixing with epoxy resin to obtain the spinel-type composite photothermal superhydrophobic coating.

[0015] Furthermore, in step S1, the molar ratio of the copper salt, iron salt, and manganese salt is 1:(1-2):(1-2); and / or

[0016] The total molar amount of the copper salt, iron salt, and manganese salt, in molar ratio to the surfactant, is 1:(0.01-0.1); and / or

[0017] The total molar ratio of the copper salt, iron salt, and manganese salt to the alkaline precipitant is 1:(3-5); and / or

[0018] The conditions for the coprecipitation reaction are: stirring at room temperature for 1 to 3 hours, followed by standing precipitation for 3 to 5 hours; the washing is done with deionized water; the drying is lyophilization at a temperature of -50°C to -55°C for 10 to 14 hours.

[0019] Further, in step S1, the copper salt is Cu(NO3)2·3H2O, the iron salt is Fe(NO3)3·9H2O, and the manganese salt is MnCl2·4H2O; and / or

[0020] The surfactant is hexadecyltrimethylammonium bromide; wherein, hexadecyltrimethylammonium bromide has good surface activity, dispersibility, stability, and biodegradability, and it has good compatibility with spinel-type CuFeMnO4 materials. Hexadecyltrimethylammonium bromide is a cationic surfactant, while the surface of spinel-type CuFeMnO4 materials may be negatively charged or electrically neutral. This charge difference leads to electrostatic interactions between the two. The cationic surfactant can adsorb onto the surface of negatively charged solid particles, thereby changing the surface properties of the particles, enhancing dispersibility and stability, and improving the dispersibility and stability of spinel-type CuFeMnO4 materials to a certain extent. Furthermore, this surfactant is inexpensive and highly safe. And / or

[0021] The alkaline precipitant is sodium hydroxide; and / or, the alkaline precipitant controls the pH of the reaction system to be 10.5–11.5.

[0022] Furthermore, in step S2, the temperature of the high-temperature heat treatment is 600℃~800℃, and the time of the high-temperature heat treatment is 1h~3h.

[0023] Furthermore, in step S2, the particle size of the obtained spinel-type CuFeMnO4 material is 50 nm to 150 nm.

[0024] Furthermore, in step S3, the mass ratio of the spinel-type CuFeMnO4 material to palm wax is 10:(1-5); and / or

[0025] The mass ratio of the spinel-type CuFeMnO4 material to the organic solvent is 1:(100-115); and / or

[0026] The organic solvent is a composite solvent of cyclohexane and ethyl acetate, wherein the volume ratio of cyclohexane to ethyl acetate is 1:(1-5); and / or

[0027] The heating and melting temperature is 60℃~80℃, and the heating and melting time is 10min~30min.

[0028] Furthermore, in step S4, the epoxy resin and the spinel-type CuFeMnO4 material are in a ratio of (1-3):1; and / or

[0029] The ultrasonic dispersion time is 20 min to 40 min.

[0030] To achieve the second objective of the invention, the technical solution adopted by the present invention is as follows:

[0031] This invention provides a spinel-type composite photothermal superhydrophobic coating, which is prepared by the above-described method for preparing a spinel-type composite photothermal superhydrophobic coating.

[0032] To achieve the third objective of the invention, the technical solution adopted by the present invention is as follows:

[0033] This invention provides an application of a spinel-type composite photothermal superhydrophobic coating, specifically the application of the spinel-type composite photothermal superhydrophobic coating prepared by the aforementioned method in anti-icing and de-icing processes.

[0034] The spinel-type composite photothermal superhydrophobic coating effectively reduces ice crystal formation and enhances anti-icing performance by reducing ice adhesion during ice crystal formation. Especially under low-temperature conditions, it prevents frost accumulation, improving equipment stability and safety.

[0035] Furthermore, the spinel-type composite photothermal superhydrophobic coating is sprayed onto the substrate surface and, after drying and curing, enables the substrate to prevent and remove ice; and / or

[0036] The spraying pressure is 3MPa to 5MPa, the drying and curing temperature is 40℃ to 120℃, and the drying and curing time is 2h to 4h. Specifically, for the spinel-type composite photothermal superhydrophobic coating, the palm wax in the coating will have different viscosities at different temperatures. Furthermore, considering that the hydrophobic and anti-icing coating formed by this spinel-type composite photothermal superhydrophobic coating must possess superhydrophobic properties, excessively high temperatures will damage the structure of the palm wax, while excessively low temperatures will lead to incomplete curing. Therefore, controlling the curing temperature at 40℃ to 120℃ and the curing time at 2h to 4h is the optimal condition.

[0037] The substrate includes a metal substrate or a non-metal substrate. The metal substrate is preferably an aluminum sheet, while the non-metal substrate can be glass, cotton cloth, etc. The metal substrate undergoes surface pretreatment before spraying. Surface pretreatment methods include sanding with 500-grit sandpaper, ultrasonically cleaning with ethanol and acetone sequentially to remove oil film and stains, and then drying. Alternatively, multiple layers can be sprayed using a spraying method.

[0038] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0039] (1) A method for preparing a spinel-type composite photothermal superhydrophobic coating according to the present invention involves first preparing a spinel-type CuFeMnO4 material with a micro-nano structure by co-precipitation of copper salt, iron salt, and manganese salt and high-temperature heat treatment, and then modifying the surface of the spinel-type CuFeMnO4 material with hydrophobicity using palm wax. The spinel-type CuFeMnO4 material with a micro-nano structure is a multi-metal oxide material with good structural stability, good photothermal performance, cost-effectiveness, and environmental friendliness. By combining the excellent photothermal conversion performance of the spinel-type CuFeMnO4 material with the low surface energy characteristics of palm wax, a synergistic effect of efficient photothermal conversion and superhydrophobic performance is achieved. Therefore, the prepared spinel-type composite photothermal superhydrophobic coating has excellent superhydrophobicity, durability, and environmental adaptability, and can provide good anti-icing and de-icing effects.

[0040] (2) The preparation method of the spinel-type composite photothermal superhydrophobic coating of the present invention has the advantages of simple process, economical cost and environmental friendliness. Moreover, the preparation conditions are mild and controllable, the preparation cost is low, the material sources are wide and the preparation efficiency is high. In addition, no complicated equipment and high cost are required. The preparation process uses environmentally friendly and non-toxic raw materials and solvents. Compared with traditional chemical synthesis methods, it has a lower environmental impact, good environmental performance and is suitable for large-scale production.

[0041] (3) The spinel-type composite photothermal superhydrophobic coating of the present invention has excellent superhydrophobicity, durability and environmental adaptability, and can play a good role in anti-icing and de-icing.

[0042] (4) The application of the spinel-type composite photothermal superhydrophobic coating of the present invention, in the application of this spinel-type composite photothermal superhydrophobic coating in anti-icing and de-icing, achieves the synergistic effect of efficient photothermal conversion and superhydrophobic properties, effectively inhibiting the formation and adhesion of ice crystals. Under normal cold conditions of -15℃ and 60%–80% humidity in a refrigerator, water droplets do not freeze after 1–13 hours. Therefore, this spinel-type composite photothermal superhydrophobic coating has excellent anti-icing effect.

[0043] (5) The application of a spinel-type composite photothermal superhydrophobic coating of the present invention, in anti-icing and de-icing, utilizes a spinel-type CuFeMnO4 material with photothermal effect combined with palm wax to form a superhydrophobic interface, achieving excellent photothermal effect for efficient de-icing. The coating formed by this spinel-type composite photothermal superhydrophobic coating can effectively reduce the formation of ice crystals and improve anti-icing performance by reducing the adhesion of ice when ice crystals form. Especially under low temperature conditions, it can prevent frost accumulation and improve the stability and safety of equipment. Attached Figure Description

[0044] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0045] Figure 1 This is a SEM image of a spinel-type composite photothermal superhydrophobic coating formed on the surface of an aluminum sheet in Embodiment 11 of the present invention.

[0046] Figure 2 The figures show the contact angle test results of the spinel-type composite photothermal superhydrophobic coatings formed at different drying and curing temperatures in Examples 11 to 15 of the present invention.

[0047] Figure 3 This is a graph showing the water droplet wettability test results of the spinel-type composite photothermal superhydrophobic coating formed in Example 11 of the present invention.

[0048] Figure 4 The graph shows the test results of the superhydrophobic wetting properties of the blank aluminum sheet and the coatings formed in Example 11, Comparative Example 1 and Comparative Example 2, respectively.

[0049] Figure 5 The graph shows the anti-icing performance test results of the spinel-type composite photothermal superhydrophobic coatings prepared in Examples 11, 16 to 19.

[0050] Figure 6 The graphs show the test results of the surface photothermal de-icing performance of the blank aluminum sheet and the coatings formed in Example 11 and Comparative Example 2, respectively. Detailed Implementation

[0051] To make the technical problem to be solved, the technical solution, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.

[0052] The terminology used in the embodiments of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. In this invention, the singular forms “a,” “the,” and “the” as used in the embodiments and appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0053] In this embodiment of the invention, a method for preparing a spinel-type composite photothermal superhydrophobic coating includes the following steps:

[0054] S1. Preparation of precursor: Dissolve copper salt, iron salt and manganese salt in water, add alkaline precipitant and mix, then add surfactant, after co-precipitation reaction, wash, centrifuge and dry to obtain metal hydroxide precipitate precursor;

[0055] S2. Preparation of spinel-type material: The metal hydroxide precipitate precursor is subjected to high-temperature heat treatment to obtain spinel-type CuFeMnO4 material;

[0056] S3. Surface hydrophobic modification: The spinel-type CuFeMnO4 material and palm wax are heated and melted in an organic solvent, and then cooled to obtain a composite photothermal hydrophobic material.

[0057] S4. Preparation of composite photothermal superhydrophobic coating: The composite photothermal hydrophobic material is added to epoxy resin and then ultrasonically dispersed to obtain the spinel-type composite photothermal superhydrophobic coating.

[0058] In some embodiments, in step S1, the molar ratio of the copper salt, iron salt, and manganese salt is 1:(1-2):(1-2); and / or

[0059] The total molar amount of the copper salt, iron salt, and manganese salt, in molar ratio to the surfactant, is 1:(0.01-0.1); and / or

[0060] The total molar ratio of the copper salt, iron salt, and manganese salt to the alkaline precipitant is 1:(3-5); and / or

[0061] The conditions for the coprecipitation reaction are: stirring at room temperature for 1 to 3 hours, followed by standing precipitation for 3 to 5 hours; the washing is done with deionized water; the drying is lyophilization at a temperature of -50°C to -55°C for 10 to 14 hours.

[0062] In some embodiments, in step S1, the copper salt is Cu(NO3)2·3H2O, the iron salt is Fe(NO3)3·9H2O, and the manganese salt is MnCl2·4H2O; and / or

[0063] The surfactant is hexadecyltrimethylammonium bromide; and / or

[0064] The alkaline precipitant is sodium hydroxide; and / or, the alkaline precipitant controls the pH of the reaction system to be 10.5–11.5.

[0065] In some embodiments, in step S2, the temperature of the high-temperature heat treatment is 600℃~800℃, and the time of the high-temperature heat treatment is 1h~3h.

[0066] In some embodiments, in step S2, the particle size of the obtained spinel-type CuFeMnO4 material is 50 nm to 150 nm.

[0067] In some embodiments, in step S3, the mass ratio of the spinel-type CuFeMnO4 material to palm wax is 10:(1-5); and / or

[0068] The mass ratio of the spinel-type CuFeMnO4 material to the organic solvent is 1:(100-115); and / or

[0069] The organic solvent is a composite solvent of cyclohexane and ethyl acetate, wherein the volume ratio of cyclohexane to ethyl acetate is 1:(1-5); and / or

[0070] The heating and melting temperature is 60℃~80℃, and the heating and melting time is 10min~30min.

[0071] In some embodiments, in step S4, the epoxy resin and the spinel-type CuFeMnO4 material are in a ratio of (1-3):1; and / or

[0072] The ultrasonic dispersion time is 20 min to 40 min.

[0073] In this embodiment of the invention, a spinel-type composite photothermal superhydrophobic coating is prepared by the above-described preparation method of a spinel-type composite photothermal superhydrophobic coating.

[0074] In this embodiment of the invention, an application of a spinel-type composite photothermal superhydrophobic coating is described, specifically the application of the spinel-type composite photothermal superhydrophobic coating prepared by the aforementioned method in anti-icing and de-icing processes.

[0075] In some embodiments, the spinel-type composite photothermal superhydrophobic coating is sprayed onto the surface of a substrate, and after drying and curing, the substrate becomes capable of preventing and removing ice; and / or

[0076] The spraying pressure is 3MPa to 5MPa, the drying and curing temperature is 40℃ to 120℃, and the drying and curing time is 2h to 4h.

[0077] The following description is based on specific embodiments.

[0078] Example 1

[0079] A method for preparing a spinel-type composite photothermal superhydrophobic coating includes the following steps:

[0080] S1. Preparation of precursor: Cu(NO3)2·3H2O, Fe(NO3)3·9H2O, and MnCl2·4H2O were dissolved in water. Under stirring, sodium hydroxide, an alkaline precipitant, was slowly added and mixed to make the pH of the reaction system 10.5-11.5. Then, cetyltrimethylammonium bromide, a surfactant, was added and stirred at room temperature for 2 hours. After standing for 4 hours to precipitate, the mixture was washed with deionized water, centrifuged, and then freeze-dried at -53℃ for 12 hours to obtain the metal hydroxide precipitate precursor.

[0081] In this embodiment, the molar ratio of Cu(NO3)2·3H2O, Fe(NO3)3·9H2O, and MnCl2·4H2O is 1:1:1; the molar ratio of the total molar amount of copper salt, iron salt, and manganese salt to the surfactant is 1:0.1; and the molar ratio of the total molar amount of copper salt, iron salt, and manganese salt to the alkaline precipitant is 1:4.

[0082] S2. Preparation of spinel-type material: The metal hydroxide precipitate precursor is subjected to high-temperature heat treatment at 600℃ for 1h to obtain spinel-type CuFeMnO4 material; wherein the particle size of the obtained spinel-type CuFeMnO4 material is 50nm~150nm.

[0083] S3. Surface hydrophobic modification: The spinel-type CuFeMnO4 material and palm wax are heated and melted in an organic solvent at 60°C for 10 min and then cooled to obtain a composite photothermal hydrophobic material. In this embodiment, the mass ratio of spinel-type CuFeMnO4 material to palm wax is 10:3; the mass ratio of spinel-type CuFeMnO4 material to organic solvent is 1:105; the organic solvent is a composite solvent of cyclohexane and ethyl acetate, and the volume ratio of cyclohexane to ethyl acetate is 1:1.

[0084] S4. Preparation of composite photothermal superhydrophobic coating: The composite photothermal superhydrophobic material is added to epoxy resin and then ultrasonically dispersed for 30 minutes to obtain the spinel-type composite photothermal superhydrophobic coating. In this embodiment, the ratio of epoxy resin to spinel-type CuFeMnO4 material is 1:1.

[0085] Example 2

[0086] A method for preparing a spinel-type composite photothermal superhydrophobic coating is disclosed. The difference between this embodiment and Example 1 is that in step S3, the mass ratio of spinel-type CuFeMnO4 material to palm wax is 10:1. The remaining preparation methods are the same as in Example 1.

[0087] Example 3

[0088] A method for preparing a spinel-type composite photothermal superhydrophobic coating is disclosed. The difference between this embodiment and Example 1 is that in step S3, the mass ratio of spinel-type CuFeMnO4 material to palm wax is 10:2. The remaining preparation methods are the same as in Example 1.

[0089] Example 4

[0090] A method for preparing a spinel-type composite photothermal superhydrophobic coating is disclosed. The difference between this embodiment and Example 1 is that in step S3, the mass ratio of spinel-type CuFeMnO4 material to palm wax is 10:4. The remaining preparation methods are the same as in Example 1.

[0091] Example 5

[0092] A method for preparing a spinel-type composite photothermal superhydrophobic coating is disclosed. The difference between this embodiment and Example 1 is that in step S3, the mass ratio of spinel-type CuFeMnO4 material to palm wax is 10:5. The remaining preparation methods are the same as in Example 1.

[0093] Example 6

[0094] A method for preparing a spinel-type composite photothermal superhydrophobic coating includes the following steps:

[0095] S1. Preparation of precursor: Cu(NO3)2·3H2O, Fe(NO3)3·9H2O, and MnCl2·4H2O were dissolved in water. Under stirring, sodium hydroxide, an alkaline precipitant, was slowly added and mixed to make the pH of the reaction system 10.5-11.5. Then, cetyltrimethylammonium bromide, a surfactant, was added and stirred at room temperature for 1 hour. After standing for 3 hours to precipitate, the mixture was washed with deionized water, centrifuged, and then freeze-dried at -50℃ for 14 hours to obtain the metal hydroxide precipitate precursor.

[0096] In this embodiment, the molar ratio of Cu(NO3)2·3H2O, Fe(NO3)3·9H2O, and MnCl2·4H2O is 1:2:1; the molar ratio of the total molar amount of copper salt, iron salt, and manganese salt to the surfactant is 1:0.01; and the molar ratio of the total molar amount of copper salt, iron salt, and manganese salt to the alkaline precipitant is 1:3.

[0097] S2. Preparation of spinel-type material: The metal hydroxide precipitate precursor is subjected to high-temperature heat treatment at 700℃ for 3h to obtain spinel-type CuFeMnO4 material; wherein, the particle size of the obtained spinel-type CuFeMnO4 material is 50nm~150nm.

[0098] S3. Surface hydrophobic modification: The spinel-type CuFeMnO4 material and palm wax are heated and melted in an organic solvent at 70°C for 30 minutes and then cooled to obtain a composite photothermal hydrophobic material. In this embodiment, the mass ratio of spinel-type CuFeMnO4 material to palm wax is 10:3; the mass ratio of spinel-type CuFeMnO4 material to organic solvent is 1:100; the organic solvent is a composite solvent of cyclohexane and ethyl acetate, and the volume ratio of cyclohexane to ethyl acetate is 1:2.

[0099] S4. Preparation of composite photothermal superhydrophobic coating: The composite photothermal superhydrophobic material is added to epoxy resin and then ultrasonically dispersed for 20 minutes to obtain the spinel-type composite photothermal superhydrophobic coating. In this embodiment, the ratio of epoxy resin to spinel-type CuFeMnO4 material is 2:1.

[0100] Example 7

[0101] A method for preparing a spinel-type composite photothermal superhydrophobic coating includes the following steps:

[0102] S1. Preparation of precursor: Cu(NO3)2·3H2O, Fe(NO3)3·9H2O, and MnCl2·4H2O were dissolved in water. Under stirring, sodium hydroxide, an alkaline precipitant, was slowly added and mixed to make the pH of the reaction system 10.5-11.5. Then, cetyltrimethylammonium bromide, a surfactant, was added and stirred at room temperature for 3 hours. After standing for 5 hours to precipitate, the mixture was washed with deionized water, centrifuged, and then freeze-dried at -55℃ for 10 hours to obtain the metal hydroxide precipitate precursor.

[0103] In this embodiment, the molar ratio of Cu(NO3)2·3H2O, Fe(NO3)3·9H2O, and MnCl2·4H2O is 1:2:2; the molar ratio of the total molar amount of copper salt, iron salt, and manganese salt to the surfactant is 1:0.05; and the molar ratio of the total molar amount of copper salt, iron salt, and manganese salt to the alkaline precipitant is 1:5.

[0104] S2. Preparation of spinel-type material: The metal hydroxide precipitate precursor is subjected to high-temperature heat treatment at 800℃ for 2h to obtain spinel-type CuFeMnO4 material; wherein the particle size of the obtained spinel-type CuFeMnO4 material is 50nm~150nm.

[0105] S3. Surface hydrophobic modification: The spinel-type CuFeMnO4 material and palm wax are heated and melted in an organic solvent at 80°C for 20 minutes and then cooled to obtain a composite photothermal hydrophobic material. In this embodiment, the mass ratio of spinel-type CuFeMnO4 material to palm wax is 10:3; the mass ratio of spinel-type CuFeMnO4 material to organic solvent is 1:115; the organic solvent is a composite solvent of cyclohexane and ethyl acetate, and the volume ratio of cyclohexane to ethyl acetate is 1:3.

[0106] S4. Preparation of composite photothermal superhydrophobic coating: The composite photothermal superhydrophobic material is added to epoxy resin and then ultrasonically dispersed for 40 minutes to obtain the spinel-type composite photothermal superhydrophobic coating. In this embodiment, the ratio of epoxy resin to spinel-type CuFeMnO4 material is 3:1.

[0107] Example 8

[0108] A method for preparing a spinel-type composite photothermal superhydrophobic coating includes the following steps:

[0109] S1. Preparation of precursor: Cu(NO3)2·3H2O, Fe(NO3)3·9H2O, and MnCl2·4H2O were dissolved in water. Under stirring, sodium hydroxide, an alkaline precipitant, was slowly added and mixed to adjust the pH of the reaction system to 10.5–11.5. Then, cetyltrimethylammonium bromide, a surfactant, was added and stirred at room temperature for 1.5 h. After standing for 3.5 h to precipitate, the mixture was washed with deionized water, centrifuged, and then freeze-dried at -51℃ for 13 h to obtain the metal hydroxide precipitate precursor.

[0110] In this embodiment, the molar ratio of Cu(NO3)2·3H2O, Fe(NO3)3·9H2O, and MnCl2·4H2O is 1:1:2; the molar ratio of the total molar amount of copper salt, iron salt, and manganese salt to the surfactant is 1:0.08; and the molar ratio of the total molar amount of copper salt, iron salt, and manganese salt to the alkaline precipitant is 1:4.

[0111] S2. Preparation of spinel-type material: The metal hydroxide precipitate precursor is subjected to high-temperature heat treatment at 650°C for 2.5 h to obtain spinel-type CuFeMnO4 material; wherein the particle size of the obtained spinel-type CuFeMnO4 material is 50 nm to 150 nm.

[0112] S3. Surface hydrophobic modification: The spinel-type CuFeMnO4 material and palm wax are heated and melted in an organic solvent at 65°C for 25 min and then cooled to obtain a composite photothermal hydrophobic material. In this embodiment, the mass ratio of spinel-type CuFeMnO4 material to palm wax is 10:3; the mass ratio of spinel-type CuFeMnO4 material to organic solvent is 1:102; the organic solvent is a composite solvent of cyclohexane and ethyl acetate, and the volume ratio of cyclohexane to ethyl acetate is 1:5.

[0113] S4. Preparation of composite photothermal superhydrophobic coating: The composite photothermal superhydrophobic material is added to epoxy resin and then ultrasonically dispersed for 25 minutes to obtain the spinel-type composite photothermal superhydrophobic coating. In this embodiment, the ratio of epoxy resin to spinel-type CuFeMnO4 material is 1.5:1.

[0114] Example 9

[0115] A method for preparing a spinel-type composite photothermal superhydrophobic coating includes the following steps:

[0116] S1. Preparation of precursor: Cu(NO3)2·3H2O, Fe(NO3)3·9H2O, and MnCl2·4H2O were dissolved in water. Under stirring, sodium hydroxide, an alkaline precipitant, was slowly added and mixed to adjust the pH of the reaction system to 10.5–11.5. Then, cetyltrimethylammonium bromide, a surfactant, was added and stirred at room temperature for 2.5 h. After standing for 4.5 h to precipitate, the mixture was washed with deionized water, centrifuged, and then freeze-dried at -54℃ for 11 h to obtain the metal hydroxide precipitate precursor.

[0117] In this embodiment, the molar ratio of Cu(NO3)2·3H2O, Fe(NO3)3·9H2O, and MnCl2·4H2O is 1:1:1; the molar ratio of the total molar amount of copper salt, iron salt, and manganese salt to the surfactant is 1:0.03; and the molar ratio of the total molar amount of copper salt, iron salt, and manganese salt to the alkaline precipitant is 1:3.5.

[0118] S2. Preparation of spinel-type material: The metal hydroxide precipitate precursor is subjected to high-temperature heat treatment at 750°C for 1.5 h to obtain spinel-type CuFeMnO4 material; wherein the particle size of the obtained spinel-type CuFeMnO4 material is 50 nm to 150 nm.

[0119] S3. Surface hydrophobic modification: The spinel-type CuFeMnO4 material and palm wax are heated and melted in an organic solvent at 75°C for 15 min and then cooled to obtain a composite photothermal hydrophobic material. In this embodiment, the mass ratio of spinel-type CuFeMnO4 material to palm wax is 10:3; the mass ratio of spinel-type CuFeMnO4 material to organic solvent is 1:110; the organic solvent is a composite solvent of cyclohexane and ethyl acetate, and the volume ratio of cyclohexane to ethyl acetate is 1:2.5.

[0120] S4. Preparation of composite photothermal superhydrophobic coating: The composite photothermal superhydrophobic material is added to epoxy resin and then ultrasonically dispersed for 35 minutes to obtain the spinel-type composite photothermal superhydrophobic coating. In this embodiment, the ratio of epoxy resin to spinel-type CuFeMnO4 material is 2.5:1.

[0121] Example 10

[0122] Application of a spinel-type composite photothermal superhydrophobic coating: Application of the spinel-type composite photothermal superhydrophobic coating prepared by any one of the preparation methods of spinel-type composite photothermal superhydrophobic coating in anti-icing and de-icing.

[0123] Example 11

[0124] An application of a spinel-type composite photothermal superhydrophobic coating involves using an aluminum sheet as the substrate. The surface of the aluminum sheet is polished with 500-grit sandpaper, followed by ultrasonic cleaning with ethanol and acetone, and then dried to complete the surface pretreatment. The spinel-type composite photothermal superhydrophobic coating prepared in Example 1 is sprayed onto the pretreated aluminum sheet surface and then dried and cured at 80°C for 3 hours, forming a spinel-type composite photothermal superhydrophobic coating on the aluminum sheet surface. The resulting spinel-type composite photothermal superhydrophobic coating enables the aluminum sheet to possess excellent anti-icing and de-icing properties.

[0125] In this embodiment, the spraying pressure is 3 MPa, the spraying cycle is 1 time, and the spraying amount is 6.25 mg / cm³. 2 .

[0126] Example 12

[0127] An application of a spinel-type composite photothermal superhydrophobic coating. The difference between this embodiment and Example 11 is that the drying and curing temperature is 40°C and the drying and curing time is 4 hours; the spraying pressure is 4 MPa, and the rest of the preparation methods are the same as in Example 1.

[0128] Example 13

[0129] An application of a spinel-type composite photothermal superhydrophobic coating is described. The difference between this embodiment and Example 11 is that the drying and curing temperature is 60°C and the drying and curing time is 3.5 hours; the spraying pressure is 5 MPa, and the rest of the preparation methods are the same as in Example 1.

[0130] Example 14

[0131] An application of a spinel-type composite photothermal superhydrophobic coating. The difference between this embodiment and Example 11 is that the drying and curing temperature is 100°C and the drying and curing time is 2.5 hours; the spraying pressure is 3 MPa to 5 MPa, and the rest of the preparation methods are the same as in Example 1.

[0132] Example 15

[0133] An application of a spinel-type composite photothermal superhydrophobic coating is described. The difference between this embodiment and Example 11 is that the drying and curing temperature is 120°C and the drying and curing time is 2 hours; the spraying pressure is 3.5 MPa, and the rest of the preparation methods are the same as in Example 1.

[0134] Example 16

[0135] An application of a spinel-type composite photothermal superhydrophobic coating is described in this embodiment, which differs from Embodiment 11 in that the spinel-type composite photothermal superhydrophobic coating prepared in Embodiment 2 is sprayed onto the surface of an aluminum sheet that has undergone surface pretreatment to form a spinel-type composite photothermal superhydrophobic coating. All other methods are the same as in Embodiment 11.

[0136] Example 17

[0137] An application of a spinel-type composite photothermal superhydrophobic coating is described in this embodiment, which differs from Embodiment 11 in that the spinel-type composite photothermal superhydrophobic coating prepared in Embodiment 3 is sprayed onto the surface of an aluminum sheet that has undergone surface pretreatment to form a spinel-type composite photothermal superhydrophobic coating. All other methods are the same as in Embodiment 11.

[0138] Example 18

[0139] An application of a spinel-type composite photothermal superhydrophobic coating is described in this embodiment, which differs from Embodiment 11 in that the spinel-type composite photothermal superhydrophobic coating prepared in Embodiment 4 is sprayed onto the surface of an aluminum sheet that has undergone surface pretreatment to form a spinel-type composite photothermal superhydrophobic coating. All other methods are the same as in Embodiment 11.

[0140] Example 19

[0141] An application of a spinel-type composite photothermal superhydrophobic coating is described in this embodiment, which differs from Embodiment 11 in that the spinel-type composite photothermal superhydrophobic coating prepared in Embodiment 5 is sprayed onto the surface of an aluminum sheet that has undergone surface pretreatment to form a spinel-type composite photothermal superhydrophobic coating. All other methods are the same as in Embodiment 11.

[0142] Comparative Example 1

[0143] The difference between Comparative Example 1 and Example 11 is that, according to Example 1, a CuFeMnO4 coating was prepared without the addition of palm wax. This CuFeMnO4 coating was then sprayed onto the surface of a pre-treated aluminum sheet and dried at 40°C for 2 hours, thus forming a CuFeMnO4 coating on the aluminum sheet surface. All other methods were the same as in Example 11.

[0144] Comparative Example 2

[0145] The difference between Comparative Example 2 and Example 11 is that, following steps S2 and S3 of Example 1, without adding spinel-type CuFeMnO4 material, palm wax was heated and melted in an organic solvent, and epoxy resin was added. After ultrasonic dispersion, a palm wax coating was prepared. The prepared palm wax coating was then sprayed onto the surface of a pre-treated aluminum sheet and dried and cured at 40°C for 2 hours, thus forming a palm wax coating on the aluminum sheet surface. All other methods were the same as in Example 11.

[0146] Structural morphology characterization

[0147] The spinel-type composite photothermal superhydrophobic coating formed on the surface of an aluminum sheet in the application of the spinel-type composite photothermal superhydrophobic coating of Example 11 was characterized in morphology using a field emission scanning electron microscope (FE-SEM) (Nova NanoSEM 450) from FEI Corporation, USA. Figure 1 As shown.

[0148] Depend on Figure 1 As can be seen, the spinel-type composite photothermal superhydrophobic coating prepared by this invention forms micron-sized wax wafers on its surface after the palm wax melts, uniformly coating CuFeMnO4 nanoparticles. The long-chain alkanes of the palm wax form a dense organic layer on the surface of the CuFeMnO4 nanoparticles, thus forming a micron-nano multi-level rough structure, exhibiting petal-like protrusions. Furthermore, the alkane chains of the palm wax form a hydrophobic barrier on the coating, thereby preventing water molecules from contacting the coating.

[0149] Performance testing

[0150] (I) Superhydrophobic Wetting Performance Test

[0151] (1) Water droplet wettability test of spinel-type composite photothermal superhydrophobic coatings formed at different drying and curing temperatures

[0152] The spinel-type composite photothermal superhydrophobic coatings formed in Examples 11 to 15 at different drying and curing temperatures were subjected to water droplet wettability tests. The contact angle data of different samples were measured, and the test results are as follows: Figure 2 As shown. Figure 2 In this context, WCA represents the contact angle. Figure 2 It is evident that the spinel-type composite photothermal superhydrophobic coatings formed at different drying and curing temperatures exhibit varying water droplet wettability, but all demonstrate good hydrophobic properties. Among them, the spinel-type composite photothermal superhydrophobic coating formed in Example 11 by drying and curing at 80°C exhibits the largest contact angle in the water droplet wettability test, reaching 160°, demonstrating high hydrophobicity.

[0153] The contact angle was measured using an OCA100 video optical contact angle measuring instrument manufactured by Dataphysics, Germany. When testing the spinel-type composite photothermal superhydrophobic coating samples of Examples 11 to 15, measurements were taken at five different locations on the surface of each sample, resulting in five measurement values. The average of these five values ​​was then calculated.

[0154] Among them, the water droplet wettability test results of the spinel-type composite photothermal superhydrophobic coating in Example 11 are as follows: Figure 3 As shown. By Figure 3 As can be seen, the spinel-type composite photothermal superhydrophobic coating formed in Example 11 has a relatively large contact angle, reaching 160°, and exhibits high hydrophobicity.

[0155] (2) Testing of superhydrophobic wettability of different coated samples

[0156] The superhydrophobic wettability of blank aluminum sheets, spinel-type composite photothermal superhydrophobic coatings, CuFeMnO4 coatings, and palm wax coatings formed in Example 11, Comparative Example 1, and Comparative Example 2, respectively, was tested, and the contact angle and sliding angle were measured. The test results are as follows: Figure 4 As shown. Figure 4 In the text, WCA represents the contact angle, SA represents the sliding angle, CuFeMnO4 represents the CuFeMnO4 coating prepared in Comparative Example 1, CW represents the palm wax coating prepared in Comparative Example 2, and CW-CuFeMnO4 represents the spinel-type composite photothermal superhydrophobic coating prepared in Example 11.

[0157] Depend on Figure 4As can be seen, the contact angles of the blank aluminum sheet and the CuFeMnO4 coating are 93.8° and 82.7°, respectively, while the contact angle of the palm wax coating is 152°, exhibiting good hydrophobic properties. When spinel-type CuFeMnO4 material is heated and melted to form a composite, the contact angle of the resulting spinel-type composite photothermal superhydrophobic coating increases to 160°. This demonstrates that palm wax modifies the surface of CuFeMnO4, effectively reducing the surface energy of the CuFeMnO4 material and improving its hydrophobic properties through the long-chain alkane coating of palm wax. Therefore, the spinel-type composite photothermal superhydrophobic coating obtained by this invention exhibits excellent hydrophobic properties.

[0158] (II) Anti-icing test

[0159] The anti-icing performance of the spinel-type composite photothermal superhydrophobic coatings prepared in Examples 11, 16 to 19 was tested. The difference between the spinel-type composite photothermal superhydrophobic coatings prepared in Examples 11, 16 to 19 was that the mass ratio of spinel-type CuFeMnO4 material to palm wax was different, namely 10:3, 10:1, 10:2, 10:4, and 10:5, respectively.

[0160] By measuring the delayed freezing time of the coatings in the above embodiments, the anti-icing performance of the coatings was determined. A longer delayed freezing time indicates better anti-icing performance. The delayed freezing time is the time it takes for a water droplet to transition from the liquid phase to the solid phase. This was recorded by a high-speed camera, with the freezing temperature set to -15°C and humidity maintained at 60%–80%. 10 μL of deionized water was pipetted onto the coating surface of different embodiments, and the delayed freezing time was then measured. The test results are as follows: Figure 5 As shown.

[0161] Depend on Figure 5 As can be seen in the delayed icing test, the delayed icing time of the spinel-type composite photothermal superhydrophobic coating first increases and then decreases with the increase of CuFeMnO4 dosage, thus allowing for the determination of a more reasonable and reliable CuFeMnO4 dosage. The test results show that the optimal delayed icing performance is achieved when the mass ratio of spinel-type CuFeMnO4 material to palm wax is 10:3, with a delayed icing time reaching 47689 s, meaning that water droplets do not freeze within 1–13 hours.

[0162] Therefore, the spinel-type composite photothermal superhydrophobic coating prepared by this invention exhibits superhydrophobicity due to its micro-nano structure on the surface. This structure can trap air, forming an air cushion layer, which reduces the actual contact area between the liquid and the coating, increases the contact angle, and prevents water droplets from wetting the surface. In other words, the presence of the air cushion layer reduces the contact between the liquid and the substrate, affecting the heat transfer of the droplets, thereby delaying ice crystal formation and significantly slowing down the freezing time.

[0163] (III) Photothermal De-icing Test

[0164] The surface photothermal de-icing performance of blank aluminum sheets, spinel-type composite photothermal superhydrophobic coatings and palm wax coatings formed in Example 11 and Comparative Example 2 were tested respectively. The test results are as follows: Figure 6 As shown.

[0165] The surface photothermal effect de-icing performance test specifically involved measuring the temperature change during the melting process of frost on the surface of the coated samples under xenon lamp irradiation. The specific testing procedure for the three samples was as follows: First, each sample was frozen for at least 1 hour to form a frost layer of a certain thickness. The freezing platform temperature was set between -20℃ and -22℃. Then, the samples were tested under a solar irradiation intensity using a xenon lamp. The test results are as follows: Figure 6 As shown.

[0166] Figure 6 In the figure, Bare's curve represents the blank aluminum sheet, CW's curve represents the palm wax coating prepared in Comparative Example 2, and CW-CuFeMnO4's curve represents the spinel-type composite photothermal superhydrophobic coating prepared in Example 11.

[0167] Depend on Figure 6 As can be seen from the comparison, under a certain solar radiation intensity, the spinel-type composite photothermal superhydrophobic coating prepared by this invention can heat up to 0℃ in 120s and to 10℃ within 10min. Therefore, the spinel-type composite photothermal superhydrophobic coating prepared by this invention has excellent photothermal effect and can quickly melt ice. However, the surface temperature of the blank aluminum sheet and the palm wax coating of Comparative Example 2 remained near 0℃ throughout the test, reaching temperature equilibrium and unable to rise further, thus failing to melt ice. It is evident that although palm wax has good hydrophobic properties, its photothermal effect is poor, and it cannot achieve the de-icing effect.

[0168] Therefore, the coating formed by the spinel-type composite photothermal superhydrophobic coating prepared by the present invention not only has excellent superhydrophobic properties, can effectively prevent icing and delay icing time, but also can efficiently remove ice due to its excellent photothermal effect.

[0169] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for preparing a spinel-type composite photothermal superhydrophobic coating, characterized in that, Includes the following steps: S1. Precursor preparation: Copper, iron, and manganese salts are dissolved in water, mixed with an alkaline precipitant, and then a surfactant is added. After co-precipitation, the mixture is washed, centrifuged, and freeze-dried at -50℃ to -55℃ for 10 to 14 hours to obtain a metal hydroxide precipitate precursor. The molar ratio of the copper, iron, and manganese salts is 1:(1~2):(1~2). The molar ratio of the total molar amount of the copper, iron, and manganese salts to the surfactant is 1:(0.01-0.1). The surfactant is hexadecyltrimethylammonium bromide. S2. Preparation of spinel-type material: The metal hydroxide precipitate precursor is subjected to high-temperature heat treatment to obtain spinel-type CuFeMnO4 material; the high-temperature heat treatment temperature is 600℃~800℃ and the high-temperature heat treatment time is 1h~3h. S3. Surface hydrophobic modification: The spinel-type CuFeMnO4 material and palm wax are heated and melted in a composite solvent of cyclohexane and ethyl acetate, and then cooled to obtain a composite photothermal hydrophobic material; the mass ratio of the spinel-type CuFeMnO4 material to palm wax is 10:(1~5); the volume ratio of cyclohexane to ethyl acetate is 1:(1~5); the heating and melting temperature is 60℃~80℃, and the heating and melting time is 10min~30min; S4. Preparation of composite photothermal superhydrophobic coating: The composite photothermal superhydrophobic material is added to epoxy resin and then ultrasonically dispersed to obtain the spinel-type composite photothermal superhydrophobic coating; the ratio of epoxy resin to spinel-type CuFeMnO4 material is (1~3):

1.

2. The preparation method of the spinel-type composite photothermal superhydrophobic coating as described in claim 1, characterized in that, In step S1, the total molar ratio of the copper salt, iron salt, and manganese salt to the alkaline precipitant is 1:(3~5); and / or The conditions for the coprecipitation reaction are: stirring at room temperature for 1 to 3 hours, followed by standing precipitation for 3 to 5 hours; the washing is performed using deionized water.

3. The preparation method of the spinel-type composite photothermal superhydrophobic coating as described in claim 1, characterized in that, In step S1, the copper salt is Cu(NO3)2·3H2O, the iron salt is Fe(NO3)3·9H2O, and the manganese salt is MnCl2·4H2O; and / or The alkaline precipitant is sodium hydroxide; and / or, the alkaline precipitant controls the pH of the reaction system to be 10.5~11.

5.

4. The preparation method of a spinel-type composite photothermal superhydrophobic coating as described in claim 1, characterized in that, In step S2, the particle size of the obtained spinel-type CuFeMnO4 material is 50nm~150nm.

5. The preparation method of a spinel-type composite photothermal superhydrophobic coating as described in claim 1, characterized in that, In step S3, the mass ratio of the spinel-type CuFeMnO4 material to the organic solvent is 1:(100~115).

6. The preparation method of a spinel-type composite photothermal superhydrophobic coating as described in claim 1, characterized in that, In step S4, the ultrasonic dispersion time is 20 min to 40 min.

7. A spinel-type composite photothermal superhydrophobic coating, characterized in that, The coating is prepared by the method described in any one of claims 1 to 6.

8. The application of a spinel-type composite photothermal superhydrophobic coating, characterized in that, The application of the spinel-type composite photothermal superhydrophobic coating prepared by the preparation method of the spinel-type composite photothermal superhydrophobic coating according to claim 7 or any one of claims 1 to 6 in anti-icing and de-icing.

9. The application of the spinel-type composite photothermal superhydrophobic coating as described in claim 8, characterized in that, The spinel-type composite photothermal superhydrophobic coating is sprayed onto the substrate surface, and after drying and curing, the substrate becomes capable of preventing and removing ice; and / or The spraying pressure is 3MPa~5MPa, the drying and curing temperature is 40℃~120℃, and the drying and curing time is 2h~4h.

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