Self-assembled photo-thermal super-hydrophobic coating material and preparation method thereof

Abstract

The invention discloses a self-assembled photo-thermal super-hydrophobic coating material and a preparation method thereof, and belongs to the field of hydrophobic materials.The preparation method comprises the steps that S1, surface modification is conducted on a first type of material and a second type of material; s2, performing self-assembly through intermolecular acting force to prepare a photo-thermal nano hybrid material; s3, increasing the surface roughness of the self-assembled hybrid material and reinforcing the hybrid network; s4, performing surface grafting reaction to reduce the surface energy of the hybrid material; and S5, adding the surface-modified powder into an organic solvent, stirring, adding resin and a curing agent, carrying out a cross-linking reaction, and continuously stirring to obtain the self-assembled super-hydrophobic photo-thermal coating material. The coating material provided by the invention can quickly remove water on the surface, and the temperature rises to a certain range under the condition of illumination. And the stability of a hybrid filler network can be improved, the surface roughness is improved, and the photo-thermal absorption and conversion efficiency is enhanced. The composite material has good stability and durability, and can be used in various extreme environments.

Claims

1. A method for preparing a self-assembled photothermal super-hydrophobic coating material, characterized in that: Includes steps: S1: Surface modification of the first and second types of materials: The first type of material modification method includes adding tris(hydroxymethyl)aminomethane to water to obtain a Tris solution, adjusting the pH value, adding dopamine hydrochloride, and then adding the first type of material to the Tris solution of dopamine hydrochloride, and continuously stirring the reaction to grow a layer of polydopamine PDA on the surface thereof, and drying to obtain a type of modified photothermal material; The second type of material modification method includes adding the second type of material to concentrated nitric acid, heating the mixture, stirring and refluxing, allowing it to fully undergo a self-assembly reaction, introducing oxygen-containing groups on its surface, and obtaining a second type of modified photothermal material; S2: Preparation of photothermal nanohybrid materials by self-assembly through intermolecular forces: dopamine-modified materials are added to water and ultrasonicated until a uniform solution is formed; at the same time, the second type of material is ultrasonically dispersed in water and then slowly added dropwise to the solution of the first type of material; finally, the mixed solution is stirred at room temperature to obtain a self-assembled hybrid photothermal material; S3: Increase the surface roughness of the self-assembled hybrid material and strengthen the hybrid network: disperse the photothermal hybrid material in a mixed solution of ethanol and alkali, stir and ultrasonicate, add a silicon source to react at room temperature, and plate a layer of SiO2 shell on the surface of the photothermal hybrid network to increase the roughness and strengthen the self-assembled hybrid filler network, and provide reactive functional groups; S4: performing a surface grafting reaction to reduce the surface energy of the hybrid material: adding a reactive fluorine-free low surface energy material and stirring at room temperature for 1 hour to reduce the surface energy of the photothermal hybrid network, and then stirring and drying to obtain a surface-modified hybrid powder material; S5: adding the surface-modified powder into an organic solvent and stirring, then adding a resin and a curing agent to carry out a cross-linking reaction, and continuing to stir to obtain a self-assembled super-hydrophobic photothermal coating material.

2. The method for preparing a self-assembled photothermal super-hydrophobic coating material according to claim 1, wherein: The concentration of dopamine hydrochloride in the modified solution is 1 mg / mL-4 mg / mL, the concentration of Tris is 10 mM-50 mM, and the pH is 8-10.

3. The method for preparing a self-assembled photothermal super-hydrophobic coating material according to claim 1, wherein: In step S1, the first type of materials includes CuS, CuSe, CdS, CdSe, TiN, Fe3O4, TiO2, SiC, AgNPs, Al2O3, ZnO, MoS2, WS2, MoSe2, WSe2 or carbon black, and its particle size is 20nm to 5000nm; the second type of materials includes graphite nanosheets, graphene, graphite powder, expandable graphite, boron nitride h-BN, black scale BP, metal organic framework MOFs or carbon nanotubes, the lateral size of the three-dimensional material is 1um-5000um, the thickness is 5nm-5000nm, the length of the two-dimensional material is 1um-30um, and the diameter is 5nm-50nm; the reaction time is 2h-12h; the heating temperature is 60℃-120℃, and the stirring reflux time is 2h-12h; The three-dimensional materials include: graphite nanosheets, graphene, graphite powder, expandable graphite, boron nitride h-BN, black scale BP and metal organic framework MOFs; The two-dimensional material includes carbon nanotubes.

4. The method for preparing the self-assembled photothermal super-hydrophobic coating material according to claim 3, characterized in that, The lateral size of the three-dimensional material is 1um-5000um, and the thickness is 5nm-5000nm. The length of the two-dimensional material is 1um-30um, and the diameter is 5nm-50nm.

5. The method for preparing the self-assembled photothermal super-hydrophobic coating material according to claim 1, wherein: In step S2, the dispersion concentrations of the first and second materials are the same, which is 0.1 g / mL-1.0 g / mL; the mass ratio of the first and second materials is 3:1-1:3; and the self-assembly reaction time is 2h-12h.

6. The method for preparing the self-assembled photothermal super-hydrophobic coating material according to claim 1, characterized in that, In step S3, the alkaline solution is ammonia water, sodium hydroxide or potassium hydroxide; the silicon source is tetraethyl orthosilicate, methyltriethoxysilane or sodium methyl silicate; the oxygen-containing group includes carboxyl, hydroxyl or carbonyl; the hybrid material includes alkaline solution: silicon source in a ratio of 1:2:1-1:8:4; and the reaction time is 0.5h-12h.

7. The method for preparing the self-assembled photothermal super-hydrophobic coating material according to claim 1, characterized in that: In step S4, the fluorine-free low surface energy material is methyltrimethoxysilane, methyltriethoxysilane, polydimethylsiloxane, hexadecyltrimethoxysilane, hexadecyltriethoxysilane, dodecyltrimethoxysilane, dodecyltriethoxysilane or octyltriethoxysilane; the drying temperature is 60°C-120°C, and the time is 1-24 hours.

8. The method for preparing the self-assembled photothermal super-hydrophobic coating material according to claim 1, characterized in that: In step S5, the organic solvent includes ethyl acetate, butyl acetate or n-hexane; the resin includes fluorocarbon resin, silicone resin, epoxy resin, acrylic resin or polyurethane.

9. A self-assembled photothermal super-hydrophobic coating material, which is made by the self-assembled photothermal super-hydrophobic coating material preparation method according to any one of claims 1 to 8, characterized in that: The raw material composition includes 1%-25% of powder particles, 60%-90% of volatile organic solvent, and 1%-25% of base resin and curing agent material; The powder particle raw material composition includes 6%-12% of a first-class modified photothermal material, 2%-4% of a second-class modified photothermal material, 1%-4% of a silicone ester, 70%-90% of an alcohol solvent, 2%-8% of water, 0.5%-2% of an alkaline material, wherein the alkaline material makes the pH of the mixed system 2-4, and 0.25%-1% of a fluorine-free low surface energy material.

10. The self-assembled photothermal super-hydrophobic coating material according to claim 9, characterized in that: The particle size of the modified photothermal material is 20nm to 5000nm.

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