Spinel type composite photo-thermal super-hydrophobic coating, preparation method thereof and application of spinel type composite photo-thermal super-hydrophobic coating in anti-icing and deicing

Abstract

The invention relates to the technical field of composite functional materials, in particular to a spinel type composite photo-thermal super-hydrophobic coating, a preparation method of the spinel type composite photo-thermal super-hydrophobic coating and application of the spinel type composite photo-thermal super-hydrophobic coating to ice prevention and deicing. The preparation method comprises the following steps: firstly, preparing a spinel type CuFeMnO4 material with a micro-nano structure from copper salt, ferric salt and manganese salt by virtue of a coprecipitation method and high-temperature heat treatment, and then carrying out surface hydrophobic modification on the spinel type CuFeMnO4 material by virtue of palm wax. The excellent photothermal conversion performance of the spinel type CuFeMnO4 material is combined with the low surface energy characteristic of the palm wax, so that the synergistic effect of efficient photothermal conversion and super-hydrophobic performance is realized; a coating layer formed by the prepared spinel type composite photo-thermal super-hydrophobic coating has excellent super-hydrophobicity, durability and environmental adaptability and can have good anti-icing and deicing effects. In addition, the preparation method has the advantages of being simple in process, economical in cost and environmentally friendly.

Description

Technical Field

[0001] The present invention relates to the technical field of composite functional materials, and particularly relates to a spinel-type composite photothermal superhydrophobic coating, a preparation method thereof, and an application thereof in anti-icing and de-icing. Background Art

[0002] With the continuous development of science and technology, the demand for anti-icing, anti-snowing, and anti-freezing technologies in various fields is increasing day by day, especially in the fields of aviation, power transmission, transportation facilities, and construction. The accumulation of ice and frost not only affects the normal use of equipment and materials, but also may bring potential safety hazards. For example, icing on aircraft wings may affect flight safety; ice on power lines may cause line breaks; ice accumulation on transportation facilities will affect driving safety. Therefore, how to effectively prevent the attachment and accumulation of ice and frost and develop a superhydrophobic anti-icing and de-icing material with long-term effectiveness has become one of the important research directions in the current anti-icing technology field.

[0003] Palm wax, as a natural wax substance, has a low surface energy and good hydrophobicity, and is widely used in the coating field. However, the coating prepared by using palm wax alone, although having a certain hydrophobicity, has poor durability, environmental adaptability, and anti-icing and de-icing performance. In the prior art, in order to better apply to the anti-icing and de-icing of various fields, there is an urgent need to increase the research and development and expansion of high-performance anti-icing and de-icing composite materials. Summary of the Invention

[0004] In order to overcome the deficiencies of the prior art, the first object of the present invention is to provide a preparation method of a spinel-type composite photothermal superhydrophobic coating. The preparation 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 achieve good anti-icing and de-icing effects.

[0005] In order to overcome the deficiencies of the prior art, the second object of the present invention is to provide a spinel-type composite photothermal superhydrophobic coating. The spinel-type composite photothermal superhydrophobic coating has excellent superhydrophobicity, durability, and environmental adaptability and can achieve good anti-icing and de-icing effects.

[0006] The third object of the present 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 object of the above-mentioned invention, the technical solution adopted by the present invention is as follows:

[0008] The present invention provides a preparation method of 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 an alkaline precipitating agent and mix, then add a surfactant. After coprecipitation reaction, wash, centrifuge, and dry to obtain a metal hydroxide precipitate precursor;

[0010] S2. Preparation of spinel-type material: Subject the metal hydroxide precipitate precursor to high-temperature heat treatment to obtain a 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 a large number of spinel-type CuFeMnO4 materials with micro-nano structure.

[0012] S3. Surface hydrophobic modification: Heat and melt-mix the spinel-type CuFeMnO4 material and palm wax in an organic solvent, and then cool to obtain a composite photothermal hydrophobic material;

[0013] S4. Preparation of composite photothermal superhydrophobic coating: Add the composite photothermal hydrophobic material to epoxy resin, and then disperse it by ultrasonic treatment to obtain the spinel-type composite photothermal superhydrophobic coating.

[0014] A preparation method of a spinel-type composite photothermal superhydrophobic coating according to the present invention, by surface-modifying the prepared spinel-type CuFeMnO4 material with micro-nano structure with palm wax, and then mixing it evenly with epoxy resin, to obtain the spinel-type composite photothermal superhydrophobic coating.

[0015] Further, 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 and the molar ratio of the surfactant is 1:(0.01 - 0.1); and / or

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

[0018] The conditions of the coprecipitation reaction are: stir at room temperature for 1 h - 3 h, and then stand for precipitation for 3 h - 5 h; the washing is carried out with deionized water; the drying is freeze-drying, the freeze-drying temperature is -50 °C - -55 °C, and the freeze-drying time is 10 h - 14 h.

[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 cetyltrimethylammonium bromide; among them, cetyltrimethylammonium bromide has good surface activity, dispersibility, stability and biodegradability, and it has good compatibility with the spinel-type CuFeMnO4 material. Cetyltrimethylammonium bromide is a cationic surfactant, while the surface of the spinel-type CuFeMnO4 material may carry negative charges or be electrically neutral. Such a charge difference will cause electrostatic interaction between the two; the cationic surfactant can adsorb on the surface of negatively charged solid particles, thereby changing the surface properties of the particles, enhancing the dispersibility and stability, and improving the dispersibility and stability of the spinel-type CuFeMnO4 material to a certain extent. And this surfactant is inexpensive and has high safety. And / or

[0021] The basic precipitating agent is sodium hydroxide; and / or, the basic precipitating agent controls the pH value of the reaction system to be 10.5 - 11.5.

[0022] Further, in step S2, the temperature of the high-temperature heat treatment is 600°C - 800°C, and the time of the high-temperature heat treatment is 1h - 3h.

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

[0024] Further, in step S3, the mass ratio of the spinel-type CuFeMnO4 material to the 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, and the volume ratio of cyclohexane to ethyl acetate is 1:(1 - 5); and / or

[0027] The temperature of the heating and melting is 60°C - 80°C, and the time of the heating and melting is 10min - 30min.

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

[0029] The time of the ultrasonic dispersion is 20min - 40min.

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

[0031] The present invention provides a spinel-type composite photothermal superhydrophobic coating, which is prepared by the preparation method of a spinel-type composite photothermal superhydrophobic coating described above.

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

[0033] The present invention provides an application of a spinel-type composite photothermal superhydrophobic coating, which is an application of the spinel-type composite photothermal superhydrophobic coating prepared by the preparation method of the spinel-type composite photothermal superhydrophobic coating described above in anti-icing and de-icing.

[0034] Among them, the coating formed by the spinel-type composite photothermal superhydrophobic coating can effectively reduce the formation of ice crystals, and improve the anti-icing performance by reducing the adhesion of ice when ice crystals are formed. Especially under low-temperature conditions, it can prevent the accumulation of frost and improve the stability and safety of equipment.

[0035] Furthermore, the spinel-type composite photothermal superhydrophobic coating is sprayed on the surface of the substrate, and after drying and curing, the substrate can be anti-iced and de-iced; and / or

[0036] The pressure of the spraying is 3 MPa to 5 MPa, the temperature of the drying and curing is 40 °C to 120 °C, and the time of the drying and curing is 2 h to 4 h. Among them, for the sprayed spinel-type composite photothermal superhydrophobic coating, since the palm wax in the composite photothermal superhydrophobic coating will have different viscosities when cured at different temperatures, and considering that the hydrophobic anti-icing coating formed by the spinel-type composite photothermal superhydrophobic coating should have superhydrophobic performance, too high temperature will damage the structure of the palm wax, and too low temperature will cause incomplete curing of the coating. Therefore, it is a better condition that the curing temperature is controlled at 40 °C to 120 °C and the curing time is 2 h to 4 h.

[0037] Among them, the substrate includes a metal substrate or a non-metal substrate. The metal substrate is preferably an aluminum sheet, and the non-metal substrate can be glass, cotton cloth, etc. The metal substrate is pretreated on the surface before spraying. The method of surface pretreatment includes polishing with 500-mesh sandpaper, ultrasonic washing with ethanol and acetone in sequence to remove the oil film and stains, and then drying. In addition, multiple layers of coatings can also be sprayed by the spraying method.

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

[0039] (1) A preparation method of a spinel-type composite photothermal superhydrophobic coating of the present invention. First, a spinel-type CuFeMnO4 material with a micro-nano structure is prepared by co-precipitation method and high-temperature heat treatment from copper salt, iron salt, and manganese salt, and then the surface of the spinel-type CuFeMnO4 material is hydrophobically modified with palm wax. Among them, the spinel-type CuFeMnO4 material with a micro-nano structure is a multi-metal oxide material with good structural stability, good photothermal performance, cost economy, 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, the 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 achieve good anti-icing and de-icing effects.

[0040] (2) A preparation method of a spinel-type composite photothermal superhydrophobic coating of the present invention has the advantages of simple process, cost economy, and environmental friendliness, and 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, there is no need for complex equipment and high costs. In the preparation process, environmentally friendly and non-toxic raw materials and solvents are used. Compared with traditional chemical synthesis methods, it has lower environmental impact, good environmental protection, and can be applied to large-scale production.

[0041] (3) A spinel-type composite photothermal superhydrophobic coating of the present invention has excellent superhydrophobicity, durability, and environmental adaptability, and can achieve good anti-icing and de-icing effects.

[0042] (4) An application of a spinel-type composite photothermal superhydrophobic coating of the present invention. The application of the spinel-type composite photothermal superhydrophobic coating in anti-icing and de-icing realizes the synergistic effect of efficient photothermal conversion and superhydrophobic performance, effectively inhibits the formation and attachment of ice crystals. In the refrigerator at -15°C and a constant cold condition with a humidity of 60% - 80%, a water droplet icing test is carried out, and the water droplets do not freeze after 1 - 13 hours. Therefore, the spinel-type composite photothermal superhydrophobic coating has excellent anti-icing effects.

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

[0044] To more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

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

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

[0047] Figure 3 It is the water droplet wettability test result diagram of the spinel-type composite photothermal superhydrophobic coating formed in Example 11 of the present invention.

[0048] Figure 4 It is the superhydrophobic wetting performance test result diagram of the blank aluminum sheet and the coatings formed in Example 11, Comparative Example 1, and Comparative Example 2 respectively.

[0049] Figure 5 It is the anti-icing performance test result diagram of the spinel-type composite photothermal superhydrophobic coatings prepared in Example 11 and Examples 16 to 19.

[0050] Figure 6 It is the surface photothermal de-icing performance test result diagram of the blank aluminum sheet and the coatings formed in Example 11 and Comparative Example 2 respectively. Detailed implementation manners

[0051] In order to make the technical problems, technical solutions, and beneficial effects to be solved by the present invention clearer, the following further elaborates on the present invention in conjunction with embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0052] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. In the present invention, the singular forms of "a", "the", and "said" used in the embodiments and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0053] In an embodiment of the present invention, a preparation method of 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 an alkaline precipitant and mix, then add a surfactant. After coprecipitation reaction, wash, centrifuge, and dry to obtain a metal hydroxide precipitate precursor;

[0055] S2. Preparation of spinel-type material: Perform high-temperature heat treatment on the metal hydroxide precipitate precursor to obtain a spinel-type CuFeMnO4 material;

[0056] S3. Surface hydrophobic modification: Heat and melt-mix the spinel-type CuFeMnO4 material and palm wax in an organic solvent, and then cool to obtain a composite photothermal hydrophobic material;

[0057] S4. Preparation of composite photothermal superhydrophobic coating: Add the composite photothermal hydrophobic material to epoxy resin, and then ultrasonically disperse 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 molar ratio of the total molar amount of the copper salt, iron salt, and manganese salt to the surfactant is 1:(0.01 - 0.1); and / or

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

[0061] The conditions of the coprecipitation reaction are: stir at room temperature for 1 h to 3 h, then stand and precipitate for 3 h to 5 h; the washing is performed with deionized water; the drying is freeze-drying, the freeze-drying temperature is -50°C to -55°C, and the freeze-drying time is 10 h to 14 h.

[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 cetyltrimethylammonium bromide; and / or

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

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

[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, and the volume ratio of cyclohexane to ethyl acetate is 1:(1 - 5); and / or

[0070] the temperature of the heating and melting is 60°C to 80°C, and the time of the heating and melting is 10 min to 30 min.

[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 time of the ultrasonic dispersion is 20 min to 40 min.

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

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

[0075] In some embodiments, the spinel-type composite photothermal superhydrophobic coating is sprayed on the surface of a substrate, and after drying and curing, the substrate can be anti-iced and de-iced; and / or

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

[0077] The following is illustrated with specific examples.

[0078] Example 1

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

[0080] S1. Preparation of precursor: Dissolve Cu(NO3)2·3H2O, Fe(NO3)3·9H2O, and MnCl2·4H2O in water. Under stirring conditions, slowly add the alkaline precipitant sodium hydroxide and mix. Then, adjust the pH value of the reaction system to 10.5 - 11.5. Next, add the surfactant cetyltrimethylammonium bromide and stir at room temperature for 2 h. Then, let it stand and precipitate for 4 h. After the coprecipitation reaction, wash with deionized water, centrifuge, and then freeze-dry at -53°C for 12 h to obtain a metal hydroxide precipitate precursor.

[0081] In this example, 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; 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: Heat-treat the metal hydroxide precipitate precursor at 600°C for 1 h to obtain a spinel-type CuFeMnO4 material. Among them, the particle size of the obtained spinel-type CuFeMnO4 material is 50 nm - 150 nm.

[0083] S3. Surface hydrophobic modification: Heat and melt the spinel-type CuFeMnO4 material and palm wax in an organic solvent at 60°C for 10 min and mix. Then, cool to obtain a composite photothermal hydrophobic material. In this example, the mass ratio of the spinel-type CuFeMnO4 material to palm wax is 10:3; the mass ratio of the spinel-type CuFeMnO4 material to the 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: Add the composite photothermal hydrophobic material to epoxy resin and then ultrasonically disperse for 30 min to obtain the spinel-type composite photothermal superhydrophobic coating. In this example, the mass ratio of epoxy resin to the spinel-type CuFeMnO4 material is 1:1.

[0085] Example 2

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

[0087] Example 3

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

[0089] Example 4

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

[0091] Example 5

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

[0093] Example 6

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

[0095] S1. Preparation of the precursor: Dissolve Cu(NO3)2·3H2O, Fe(NO3)3·9H2O, and MnCl2·4H2O in water. Under stirring conditions, slowly add the alkaline precipitant sodium hydroxide and mix. Then, adjust the pH value of the reaction system to 10.5 - 11.5. Add the surfactant cetyltrimethylammonium bromide, stir at room temperature for 1 h, then let it stand and precipitate for 3 h. After the coprecipitation reaction, wash with deionized water, centrifuge, and then freeze-dry at -50°C for 14 h to obtain a metal hydroxide precipitate precursor.

[0096] In this example, 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 the copper salt, iron salt, and manganese salt to the surfactant is 1:0.01; the molar ratio of the total molar amount of the copper salt, iron salt, and manganese salt to the alkaline precipitant is 1:3.

[0097] S2. Preparation of the spinel-type material: Heat-treat the metal hydroxide precipitate precursor at 700°C for 3 h to obtain a spinel-type CuFeMnO4 material. Among them, the particle size of the obtained spinel-type CuFeMnO4 material is 50 nm - 150 nm.

[0098] S3. Surface hydrophobic modification: The spinel-type CuFeMnO4 material and palm wax are heated and melted at 70 °C for 30 min and mixed in an organic solvent, and then cooled to obtain a composite photothermal hydrophobic material; in this embodiment, the mass ratio of the spinel-type CuFeMnO4 material to palm wax is 10:3; the mass ratio of the spinel-type CuFeMnO4 material to the 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 hydrophobic material is added to epoxy resin and then ultrasonically dispersed for 20 min to obtain the spinel-type composite photothermal superhydrophobic coating. In this embodiment, the mass ratio of epoxy resin to the spinel-type CuFeMnO4 material is 2:1.

[0100] Example 7

[0101] A preparation method of 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 are dissolved in water. Under stirring conditions, sodium hydroxide as an alkaline precipitating agent is slowly added and mixed. Then, the pH value of the reaction system is adjusted to 10.5 - 11.5. Then, cetyltrimethylammonium bromide as a surfactant is added, and stirring is carried out at room temperature for 3 h. Then, it is allowed to stand and precipitate for 5 h. After the coprecipitation reaction, it is washed with deionized water, centrifuged, and then freeze-dried at -55 °C for 10 h to obtain a 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; the molar ratio of the total molar amount of copper salt, iron salt, and manganese salt to the alkaline precipitating agent is 1:5;

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

[0105] S3. Surface hydrophobic modification: The spinel-type CuFeMnO4 material and palm wax are heated and melted at 80 °C for 20 min and mixed in an organic solvent, and then cooled to obtain a composite photothermal hydrophobic material; in this embodiment, the mass ratio of the spinel-type CuFeMnO4 material to palm wax is 10:3; the mass ratio of the spinel-type CuFeMnO4 material to the 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 hydrophobic material is added to epoxy resin, and then ultrasonically dispersed for 40 min to obtain the spinel-type composite photothermal superhydrophobic coating. In this embodiment, the mass ratio of epoxy resin to the spinel-type CuFeMnO4 material is 3:1.

[0107] Example 8

[0108] A preparation method of a spinel-type composite photothermal superhydrophobic coating, comprising the following steps:

[0109] S1. Preparation of precursor: Dissolve Cu(NO3)2·3H2O, Fe(NO3)3·9H2O, and MnCl2·4H2O in water. Under stirring conditions, slowly add the alkaline precipitant sodium hydroxide and mix. Then, adjust the pH value of the reaction system to 10.5 - 11.5. Next, add the surfactant cetyltrimethylammonium bromide, stir at room temperature for 1.5 h, and then let it stand and precipitate for 3.5 h. After the coprecipitation reaction, wash with deionized water, centrifuge, and then freeze-dry at -51 °C for 13 h to obtain a 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; 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: Heat-treat the metal hydroxide precipitate precursor at 650 °C for 2.5 h to obtain a spinel-type CuFeMnO4 material; among them, the particle size of the obtained spinel-type CuFeMnO4 material is 50 nm - 150 nm.

[0112] S3. Surface hydrophobic modification: The spinel-type CuFeMnO4 material and palm wax are heated and melted at 65 °C for 25 min and mixed in an organic solvent, and then cooled to obtain a composite photothermal hydrophobic material. In this example, the mass ratio of the spinel-type CuFeMnO4 material to palm wax is 10:3; the mass ratio of the spinel-type CuFeMnO4 material to the 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 hydrophobic material is added to epoxy resin, and then ultrasonically dispersed for 25 min to obtain the spinel-type composite photothermal superhydrophobic coating. In this example, the mass ratio of epoxy resin to the spinel-type CuFeMnO4 material is 1.5:1.

[0114] Example 9

[0115] A preparation method of 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 are dissolved in water. Under stirring conditions, sodium hydroxide, an alkaline precipitating agent, is slowly added and mixed. Then, the pH value of the reaction system is adjusted to 10.5 - 11.5. Next, cetyltrimethylammonium bromide, a surfactant, is added, and stirring is carried out at room temperature for 2.5 h. Then, it is left to stand and precipitate for 4.5 h. After the coprecipitation reaction, it is washed with deionized water, centrifuged, and then freeze-dried at -54 °C for 11 h to obtain a metal hydroxide precipitate precursor.

[0117] In this example, 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; the molar ratio of the total molar amount of copper salt, iron salt, and manganese salt to the alkaline precipitating agent 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 a spinel-type CuFeMnO4 material. Among them, the particle size of the obtained spinel-type CuFeMnO4 material is 50 nm - 150 nm.

[0119] S3. Surface hydrophobic modification: The spinel-type CuFeMnO4 material and palm wax are heated and melted at 75 °C for 15 min and mixed in an organic solvent, and then cooled to obtain a composite photothermal hydrophobic material. In this example, the mass ratio of the spinel-type CuFeMnO4 material to palm wax is 10:3; the mass ratio of the spinel-type CuFeMnO4 material to the 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 hydrophobic material is added to epoxy resin, and then ultrasonically dispersed for 35 min to obtain the spinel-type composite photothermal superhydrophobic coating. In this example, the mass ratio of epoxy resin to the 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 the preparation method of any one of Examples 1 to 9 in anti-icing and de-icing.

[0123] Example 11

[0124] Application of a spinel-type composite photothermal superhydrophobic coating. Aluminum sheet is used as the substrate. The surface of the aluminum sheet is polished with 500-mesh sandpaper, and then the aluminum sheet is ultrasonically washed with ethanol and acetone in sequence, and then dried to complete the surface pretreatment of the aluminum sheet. The spinel-type composite photothermal superhydrophobic coating prepared in Example 1 is sprayed on the surface of the aluminum sheet that has completed the surface pretreatment, and then dried and cured at 80 °C for 3 h, and a spinel-type composite photothermal superhydrophobic coating is formed on the surface of the aluminum sheet. The formed spinel-type composite photothermal superhydrophobic coating can endow the aluminum sheet with excellent anti-icing and de-icing performance.

[0125] In this example, the spraying pressure is 3 MPa, the spraying cycle is 1 time, and the spraying dosage is 6.25 mg / cm 2 .

[0126] Example 12

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

[0128] Example 13

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

[0130] Example 14

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

[0132] Example 15

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

[0134] Example 16

[0135] Application of a spinel-type composite photothermal superhydrophobic coating. The difference between this example and Example 11 is that the spinel-type composite photothermal superhydrophobic coating prepared in Example 2 is sprayed on the surface of the aluminum sheet that has completed surface pretreatment to form a spinel-type composite photothermal superhydrophobic coating. The remaining methods are the same as those in Example 11.

[0136] Example 17

[0137] Application of a spinel-type composite photothermal superhydrophobic coating. The difference between this example and Example 11 is that the spinel-type composite photothermal superhydrophobic coating prepared in Example 3 is sprayed on the surface of the aluminum sheet that has completed surface pretreatment to form a spinel-type composite photothermal superhydrophobic coating. The remaining methods are the same as those in Example 11.

[0138] Example 18

[0139] Application of a spinel-type composite photothermal superhydrophobic coating. The difference between this example and Example 11 is that the spinel-type composite photothermal superhydrophobic coating prepared in Example 4 is sprayed on the surface of the aluminum sheet that has completed surface pretreatment to form a spinel-type composite photothermal superhydrophobic coating. The remaining methods are the same as those in Example 11.

[0140] Example 19

[0141] Application of a spinel-type composite photothermal superhydrophobic coating. The difference between this example and Example 11 is that the spinel-type composite photothermal superhydrophobic coating prepared in Example 5 is sprayed on the surface of an aluminum sheet that has completed surface pretreatment to form a spinel-type composite photothermal superhydrophobic coating. All other methods are the same as those in Example 11.

[0142] Comparative Example 1

[0143] The difference between this Comparative Example 1 and Example 11 is that, according to Example 1, without adding palm wax, a CuFeMnO4 coating was prepared, and then the prepared CuFeMnO4 coating was sprayed on the surface of an aluminum sheet that had completed surface pretreatment, and then dried and cured at 40°C for 2 h, that is, a CuFeMnO4 coating was formed on the aluminum sheet surface. All other methods are the same as those in Example 11.

[0144] Comparative Example 2

[0145] The difference between this Comparative Example 2 and Example 11 is that, according to Steps S2 and S3 of Example 1, without adding the spinel-type CuFeMnO4 material, palm wax was heated and melted under an organic solvent, and epoxy resin was added, and after ultrasonic dispersion, a palm wax coating was prepared. Then the prepared palm wax coating was sprayed on the surface of an aluminum sheet that had completed surface pretreatment, and then dried and cured at 40°C for 2 h, that is, a palm wax coating was formed on the aluminum sheet surface. All other methods are the same as those in Example 11.

[0146] Structural morphology characterization

[0147] A spinel-type composite photothermal superhydrophobic coating formed on the surface of an aluminum sheet in the application of a spinel-type composite photothermal superhydrophobic coating in Example 11 was subjected to morphology characterization by a field emission scanning electron microscope (FE-SEM) (Nova NanoSEM 450) of FEI Company, USA, as Figure 1 shown.

[0148] It can be Figure 1 seen that for the spinel-type composite photothermal superhydrophobic coating prepared in the present invention, the palm wax on its surface forms micron-sized wax wafers after melting and uniformly coats the CuFeMnO4 nanoparticles, and the long-chain alkanes of the palm wax form a dense organic layer on the surface of the CuFeMnO4 nanoparticles, thereby forming a micro-nano multi-level rough structure, presenting petal-like protrusions. Moreover, the alkane chains of the palm wax form a hydrophobic barrier on the coating, thereby blocking the contact between water molecules and the coating.

[0149] Performance testing

[0150] (I) Superhydrophobic wetting performance testing

[0151] (1) Wettability test of water droplets on 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 respectively subjected to the wettability test of water droplets, and the contact angle data of different samples were measured. The test results are as Figure 2 shown. Figure 2 In, WCA represents the contact angle. From Figure 2 it can be seen that for the spinel - type composite photothermal superhydrophobic coatings formed at different drying and curing temperatures, there are differences in their water droplet wettability, but they all have good hydrophobic properties. Among them, the spinel - type composite photothermal superhydrophobic coating formed by drying and curing at 80 °C in Example 11 has the largest contact angle in the water droplet wettability test, and the contact angle reaches 160°, showing high hydrophobicity.

[0153] Among them, the contact angle was measured using the video optical contact angle measuring instrument OCA100 produced by Dataphysics in Germany. When testing the spinel - type composite photothermal superhydrophobic coating samples of the above - mentioned Examples 11 to 15, 5 different positions on the surface of each sample were selected for measurement to obtain 5 measurement values, and then the average value of the obtained 5 measurement values was taken.

[0154] Among them, the situation of the water droplet wettability test of the spinel - type composite photothermal superhydrophobic coating in Example 11 is as Figure 3 shown. From Figure 3 it can be seen that the contact angle of the spinel - type composite photothermal superhydrophobic coating formed in Example 11 is relatively large, reaching 160, showing high hydrophobicity.

[0155] (2) Superhydrophobic wetting performance test of different coating samples

[0156] The blank aluminum sheet, and the spinel - type composite photothermal superhydrophobic coatings, CuFeMnO4 coatings, and palm wax coatings respectively formed in Example 11, Comparative Example 1, and Comparative Example 2 were respectively subjected to the superhydrophobic wetting performance test, and the contact angle and sliding angle were respectively measured. The test results are as Figure 4 shown. Figure 4 In, 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] From Figure 4It can be seen that the contact angles of the blank aluminum sheet and the CuFeMnO4 coating are 93.8° and 82.7° respectively, and the contact angle of the palm wax coating is 152°, showing good hydrophobic properties. When the spinel-type CuFeMnO4 material is heated and melted with palm wax to prepare the spinel-type composite photothermal superhydrophobic coating, the contact angle is increased to 160°. On the one hand, it proves that the palm wax has surface-modified CuFeMnO4, and the surface energy of the CuFeMnO4 material is effectively reduced by the long-chain alkane coating of palm wax, and the hydrophobic performance is improved. Therefore, the coating formed by the spinel-type composite photothermal superhydrophobic coating prepared in the present invention has excellent hydrophobic properties.

[0158] (2) Anti-icing test

[0159] The spinel-type composite photothermal superhydrophobic coatings prepared in Example 11 and Examples 16 to 19 were respectively subjected to anti-icing performance tests. Among them, the spinel-type composite photothermal superhydrophobic coatings prepared in Example 11 and Examples 16 to 19 are different in that the mass ratio of the spinel-type CuFeMnO4 material to palm wax is different, which are 10:3, 10:1, 10:2, 10:4, and 10:5 respectively.

[0160] By measuring the delayed icing time of the coatings of the above examples, the anti-icing performance of the coatings can be further known. The longer the delayed icing time, the better the anti-icing performance. Among them, the delayed icing time is the time for the water droplet to change from the liquid phase to the solid phase, which is recorded by a high-speed camera. The freezing temperature is set at -15°C, the humidity is kept at 60% - 80%, and a pipette gun is used to take 10 μL of deionized water and drop it onto the surfaces of the coatings of different examples, and then the delayed icing time is measured. The test results are as Figure 5 shown.

[0161] As Figure 5 can be seen, in the delayed icing test, it can be clearly seen that as the amount of CuFeMnO4 used increases, the delayed icing time performance of the spinel-type composite photothermal superhydrophobic coating has a trend of first increasing and then decreasing, so a more reasonable and reliable amount of CuFeMnO4 used can be determined. The test results show that when the mass ratio of the spinel-type CuFeMnO4 material to palm wax is 10:3, it has the best delayed icing performance, and the delayed icing time reaches 47689 s, that is, the water droplet does not freeze within 1 - 13 h.

[0162] Therefore, the spinel-type composite photothermal superhydrophobic coating prepared by the present invention has a micro-nano structure on its surface. This structure can capture air and form an air cushion layer, thereby reducing the actual contact area between the liquid and the coating, increasing the contact angle, and preventing water droplets from wetting the surface, thus exhibiting superhydrophobicity and having good superhydrophobic performance. That is to say, the presence of the air cushion layer reduces the contact between the liquid and the substrate, affects the heat transfer of the liquid droplets, and then delays the formation of ice crystals, greatly delaying the icing time.

[0163] (III) Photothermal de-icing test

[0164] The surface photothermal effect de-icing performance tests were carried out on the blank aluminum sheet, and the spinel-type composite photothermal superhydrophobic coatings and palm wax coatings formed in Example 11 and Comparative Example 2 respectively. The test results are as Figure 6 shown.

[0165] Among them, the surface photothermal effect de-icing performance test is specifically to test the temperature change during the melting process of the frost on the surface of the coating sample under the irradiation of a xenon lamp. The specific test processes of the above three samples are as follows: First, the three samples were frozen to form a frost layer with a certain thickness for more than 1 h, and the temperature of the freezing platform was set at -20°C to -22°C. Then, through the irradiation of the xenon lamp, the test was carried out under the intensity of one sun's light. The test results are as Figure 6 shown.

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

[0167] It can be Figure 6 seen that by comparison, under the intensity of one sun's light, a spinel-type composite photothermal superhydrophobic coating prepared by the present invention can be heated to 0°C in 120 s and to 10°C in 10 min. Therefore, the spinel-type composite photothermal superhydrophobic coating prepared by the present invention has excellent photothermal effect and can quickly melt ice. However, the surface temperature of the blank aluminum sheet and the palm wax coating in Comparative Example 2 remained near 0°C throughout the test, reaching temperature equilibrium and unable to rise further, so they could not melt ice. It can be seen that although palm wax has good hydrophobic performance, its photothermal effect is poor and it cannot achieve the de-icing effect.

[0168] Therefore, the coating formed by a spinel-type composite photothermal superhydrophobic coating prepared by the present invention not only has excellent superhydrophobic performance, can prevent ice well and delay the icing time, but also has excellent photothermal effect and can thus efficiently de-ice.

[0169] The above are only the preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included within the protection scope of the present application.

Claims

1. A preparation method of a spinel-type composite photothermal superhydrophobic coating, characterized in that, It includes the following steps: S1. Preparation of precursor: Dissolve copper salt, iron salt, and manganese salt in water, add an alkaline precipitant and mix, then add a surfactant. After coprecipitation reaction, wash, centrifuge, and dry to obtain a metal hydroxide precipitate precursor; S2. Preparation of spinel-type material: Perform high-temperature heat treatment on the metal hydroxide precipitate precursor to obtain a spinel-type CuFeMnO4 material; S3. Surface hydrophobic modification: Heat and melt-mix the spinel-type CuFeMnO4 material and palm wax in an organic solvent, and cool to obtain a composite photothermal hydrophobic material; S4. Preparation of composite photothermal superhydrophobic coating: Add the composite photothermal hydrophobic material to epoxy resin, and then perform ultrasonic dispersion to obtain the spinel-type composite photothermal superhydrophobic coating.

2. The preparation method of a spinel-type composite photothermal superhydrophobic coating according to claim 1, characterized in that, In step S1, the molar ratio of the copper salt, iron salt, and manganese salt is 1:(1-2):(1-2); and / or the molar ratio of the total molar amount of the copper salt, iron salt, and manganese salt to the surfactant is 1:(0.01-0.1); and / or the molar ratio of the total molar amount of the copper salt, iron salt, and manganese salt to the alkaline precipitant is 1:(3-5); and / or The conditions of the coprecipitation reaction are: stir at room temperature for 1 h to 3 h, and then stand for precipitation for 3 h to 5 h; the washing is carried out with deionized water; the drying is freeze-drying, the freeze-drying temperature is -50°C to -55°C, and the freeze-drying time is 10 h to 14 h.

3. The preparation method of a spinel-type composite photothermal superhydrophobic coating according to 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 surfactant is cetyltrimethylammonium bromide; and / or the alkaline precipitant is sodium hydroxide; and / or, the alkaline precipitant controls the pH value of the reaction system to be 10.5 to 11.

5.

4. The preparation method of a spinel-type composite photothermal superhydrophobic coating according to claim 1, characterized in that, In step S2, the temperature of the high-temperature heat treatment is 600°C to 800°C, and the time of the high-temperature heat treatment is 1 h to 3 h.

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

6. The preparation method of a spinel-type composite photothermal superhydrophobic coating according to claim 1, characterized in that, In step S3, the mass ratio of the spinel-type CuFeMnO4 material to palm wax is 10:(1-5); and / or the mass ratio of the spinel-type CuFeMnO4 material to the organic solvent is 1:(100-115); and / or the organic solvent is a composite solvent of cyclohexane and ethyl acetate, and the volume ratio of cyclohexane to ethyl acetate is 1:(1-5); and / or the temperature of the heat melting is 60°C to 80°C, and the time of the heat melting is 10 min to 30 min.

7. The preparation method of a spinel-type composite photothermal superhydrophobic coating according to claim 1, characterized in that, In step S4, the epoxy resin and the spinel-type CuFeMnO4 material are in a ratio of (1-3):1; and / or the time of the ultrasonic dispersion is 20 min to 40 min.

8. A spinel-type composite photothermal superhydrophobic coating, characterized in that, It is obtained by the preparation method of a spinel-type composite photothermal superhydrophobic coating according to any one of claims 1 to 7.

9. Application of a spinel-type composite photothermal superhydrophobic coating, characterized in that, Application of a spinel-type composite photothermal superhydrophobic coating prepared by the preparation method of the spinel-type composite photothermal superhydrophobic coating according to any one of claims 1 to 7 in anti-icing and de-icing.

10. Use of a spinel-type composite photothermal superhydrophobic coating as described in claim 9, characterized in that, The spinel-type composite photothermal superhydrophobic coating is sprayed on the surface of a substrate, and after drying and curing, the substrate can be anti-iced and de-iced; and / or The pressure of the spraying is 3 MPa to 5 MPa, the temperature of the drying and curing is 40 °C to 120 °C, and the time of the drying and curing is 2 h to 4 h.

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