Micro-nano surface structure antifouling self-cleaning coating and preparation method thereof

Abstract

The application provides a kind of micro-nano surface structure antifouling self-cleaning paint, the paint comprises the following ingredients: water-based polyurethane acrylate is 25-35%, photocatalytic degradation particles are 10-20%, dispersing agent is 1-2%, defoaming agent is 1-2%, UV photoinitiator is 3-5%, adhesion promoter is 0.4-1%, and water is the balance;Wherein, the water-based polyurethane acrylate is hard chain polyurethane acrylate, and the photocatalytic degradation particles are coated with water-based polyurethane acrylate, which is soft chain water-based polyurethane acrylate.The application makes the coating surface wrinkle through the action of UV curing, and obtains a coating with self-cleaning effect.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of functional coating technology, in particular to a micro-nano surface structure anti-fouling self-cleaning coating. BACKGROUND

[0002] Self-cleaning coating can automatically remove surface contaminants or dust particles under the action of external forces such as gravity, rain, wind, etc. or through photocatalytic degradation, has the advantages of water saving, energy saving, environmental protection, etc. and has important application prospects in the construction, transportation, new energy and other industries. In recent years, it has become one of the research hotspots of advanced functional coatings.

[0003] The anti-fouling performance of self-cleaning materials is mainly affected by two aspects: on the one hand, fluorine-containing or silicon-containing compounds with low surface energy are used to physically or chemically modify the surface of the coating; on the other hand, rough or smooth surface topography is prepared, including superhydrophobic coating and superamphiphobic coating. Superhydrophobic coating is a kind of functional biomimetic coating prepared by simulating the hydrophobic properties of lotus leaves, cabbage, rose petals and other surfaces, which can achieve a water contact angle (WCA) much greater than 150° and a water sliding angle (WSA) less than 10°. Water droplets can easily slide off the surface and take away contaminants, showing excellent self-cleaning properties. Studies have found that surface roughness and chemical composition play a key role in achieving superhydrophobic materials. Researchers have prepared many superhydrophobic coatings based on the following two principles: (1) low surface energy substances modify rough surfaces; (2) increase the roughness of the superhydrophobic coating surface. However, the anti-fouling effect of most superhydrophobic materials is relatively short-lived because the superhydrophobic state is a metastable interfacial state. During use, the superhydrophobic surface can easily change from the non-wetting Cassie-Baxter state to the completely wetting Wenzel state. In addition, the superhydrophobic coating will lose its superhydrophobic properties when subjected to low surface energy molecule degradation, external pressure, mechanical vibration and other actions, resulting in poor durability of the coating surface. SUMMARY

[0004] The technical problem to be solved is to provide a micro-nano surface structure anti-fouling self-cleaning coating, which can make the coating surface wrinkle through UV curing, and obtain a coating with self-cleaning effect.

[0005] Technical solution: A micro-nano surface structure anti-fouling self-cleaning coating, the coating comprises the following ingredients:

[0006]

[0007]

[0008] The water-based polyurethane acrylate A is a hard-chain polyurethane acrylate; the water-based polyurethane acrylate B coated in the photocatalytic degradation particles is a soft-chain water-based polyurethane acrylate.

[0009] Preferably, the preparation method of the water-based polyurethane acrylate is as follows:

[0010] S11. Stir and mix isophorone diisocyanate, dihydric alcohol and dibutyltin dilaurate uniformly, then pass nitrogen gas and react at 50-60℃ for 1-2h, wherein the initial molar ratio of -NCO and -OH functional groups is 2-4:1;

[0011] S12. Dissolve 2,2-dimethylol propionic acid in N,N-dimethylformamide, add 1-2 drops of dibutyltin dilaurate dropwise, control the drop rate, and add to the system of step S1, then warm up to 40-50℃ for chain extension reaction for 1-2h, wherein the addition amount of 2,2-dimethylol propionic acid in the whole system is 3-4wt%;

[0012] S13. Add hydroquinone and beta-hydroxyethyl methacrylate dropwise to the reaction system, warm up to 45-55℃ for end-capping reaction, then cool down and add TEA for neutralization to obtain the water-based polyurethane acrylate.

[0013] Preferably, the dihydric alcohol is polyethylene glycol, when the polyethylene glycol is any one of polyethylene glycol 200, polyethylene glycol 300 or polyethylene glycol 400, a hard-chain water-based polyurethane acrylate is obtained; when the polyethylene glycol is any one of polyethylene glycol 1000, polyethylene glycol 2000, polyethylene glycol 4000 or polyethylene glycol 6000, a soft-chain water-based polyurethane acrylate is obtained. Preferably, the preparation method of the photocatalytic degradation particles comprises the following steps:

[0014] S21. Disperse PS microspheres into an aqueous ethanol solution containing cetyltrimethylammonium bromide, stir and disperse uniformly to obtain a dispersion, add ammonia water in the dispersion, continue to stir, and finally slowly add tetrabutyl titanate dropwise, react at constant temperature to obtain a titanium dioxide precursor, and calcine the titanium dioxide precursor to obtain hollow mesoporous titanium dioxide;

[0015] S22. Add the soft-chain water-based polyurethane acrylate into water, stir and disperse uniformly, immerse the hollow mesoporous titanium dioxide prepared in step S11 in the polyurethane acrylate solution, and immerse in a vacuum environment to obtain titanium dioxide particles adsorbed with polyurethane acrylate;

[0016] S23. Add nano-titanium dioxide into an aqueous solution of sodium dodecyl sulfate, ultrasonically disperse uniformly, add initiator potassium persulfate, then add methyl methacrylate, and heat to react to obtain a poly-methyl methacrylate solution containing nano-titanium dioxide;

[0017] S24. The titanium dioxide particles adsorbed with polyurethane acrylate prepared in step S22 are added to the polymethacrylate solution containing nano-titanium dioxide prepared in step S23 to coat the surface of the titanium dioxide particles adsorbed with polyurethane acrylate with polymethacrylate, thereby obtaining photocatalytic degradation particles.

[0018] Preferably, the concentration of the PS microspheres in the dispersion liquid in step S21 is 0.1-0.2 mg / mL, the concentration of cetyltrimethylammonium bromide is 0.3-0.4 mg / mL, the concentration of ammonia water is 1-2 vt%, and the concentration of tetrabutyl titanate is 0.5-1 vt%.

[0019] Preferably, the temperature of the constant temperature reaction in step S21 is 50-60℃, and the time is 1-2 h; the calcination temperature is 500-550℃, and the calcination time is 2-3 h.

[0020] Preferably, the immersion time in step S22 is 10-20 min, and the vacuum degree is -0.2 to -0.1 MPa.

[0021] Preferably, the mass ratio of methyl methacrylate to nano-titanium dioxide in step S23 is 10:1-2, the temperature of the heating reaction is 70-80℃, and the time is 10-15 h.

[0022] The preparation method of the micro-nano surface structure anti-fouling self-cleaning coating described above comprises the following steps: the water-based polyurethane acrylate is first added to water, and after uniform stirring, the photocatalytic degradation particles, the dispersing agent, the defoaming agent, the UV photoinitiator and the adhesion promoter are sequentially added, and uniform stirring is performed to obtain the micro-nano surface structure anti-fouling self-cleaning coating.

[0023] Beneficial effects: The micro-nano surface structure anti-fouling self-cleaning coating has the following advantages:

[0024] 1. In the present application, hollow mesoporous titanium dioxide particles are first prepared, polyurethane acrylate containing more soft chains is adsorbed on the titanium dioxide particles, and the microspheres are coated with photodegradable polymethacrylate, and the coating layer of the polymethacrylate contains nanometer titanium dioxide. In the process of ultraviolet curing, titanium dioxide can catalyze the faster degradation of polymethacrylate, so that the polyurethane acrylate containing more soft chains coated in the titanium dioxide particles can flow out, and in the entire coating, there is also polyurethane acrylate containing less soft chains. The outer layer of the polyurethane acrylate containing less soft chains is cured first, and the polyurethane acrylate containing more soft chains is cured later. The surface of the polyurethane acrylate containing less soft chains is cured first and has no restriction on shrinkage. Then when the surface layer of the polyurethane acrylate containing more soft chains is cured, its shrinkage will be constrained by the adhesion between the coating and the substrate. The cohesive force caused by the internal tension acts on the already shrunk upper layer, causing compression of the upper layer, and finally producing micro-nano structure wrinkles on the surface layer, obtaining a coating with micro-nano surface structure.

[0025] 2. In the present application, two different particle sizes of titanium dioxide are used in combination, which can further enhance the micro-nano effect of the coating surface. When the polymethacrylate degrades, the nanometer titanium dioxide in the polymethacrylate film is exposed, and the coating contains both micron-sized titanium dioxide and nanometer-sized titanium dioxide. Finally, a coating with micro-nano surface structure is obtained. DETAILED DESCRIPTION

[0026] The present application will be further described below in conjunction with examples, which are an explanation of the present application and the present application is not limited to the following examples:

[0027] Example 1

[0028] The preparation method of the water-based soft-chain polyurethane acrylate is as follows:

[0029] S11. Stir and mix isophorone diisocyanate, polyethylene glycol 1000 and dibutyltin dilaurate uniformly, then pass nitrogen at 50℃ for 2h, wherein the initial molar ratio of -NCO and -OH functional groups is 2:1;

[0030] S12. Dissolve 2,2-dimethylol propionic acid in N,N-dimethylformamide, add 1 drop of dibutyltin dilaurate, control the drop speed, and drop into the system of step S1, heat to 40℃ for chain extension reaction for 2h, wherein the addition amount of 2,2-dimethylol propionic acid in the whole system is 3wt%;

[0031] S13. Add hydroquinone and beta-hydroxyethyl methacrylate to the reaction system, heat to 55℃ for end-capping reaction, then cool down and add TEA for neutralization to obtain water-based polyurethane acrylate.

[0032] Example 2

[0033] The preparation method of the aqueous soft-chain polyurethane acrylate is as follows:

[0034] S11. Stir and mix isophorone diisocyanate, polyethylene glycol 2000 and dibutyltin dilaurate uniformly, then pass nitrogen gas and react at 60°C for 1h, wherein the initial molar ratio of -NCO and -OH functional groups is 3:1;

[0035] S12. Dissolve 2,2-dimethylol propionic acid in N,N-dimethylformamide, add 1 drop of dibutyltin dilaurate dropwise into the system of step S1, control the drop rate, and perform chain extension reaction at 40°C for 2h, wherein the addition amount of 2,2-dimethylol propionic acid in the whole system is 3wt%;

[0036] S13. Add hydroquinone and beta-hydroxyethyl methacrylate dropwise into the reaction system, heat to 55°C, perform end capping reaction, and then add TEA after cooling to perform neutralization, to obtain the aqueous polyurethane acrylate.

[0037] Example 3

[0038] The preparation method of the aqueous soft-chain polyurethane acrylate is as follows:

[0039] S11. Stir and mix isophorone diisocyanate, polyethylene glycol 4000 and dibutyltin dilaurate uniformly, then pass nitrogen gas and react at 55°C for 1.5h, wherein the initial molar ratio of -NCO and -OH functional groups is 2:1;

[0040] S12. Dissolve 2,2-dimethylol propionic acid in N,N-dimethylformamide, add 2 drops of dibutyltin dilaurate dropwise into the system of step S1, control the drop rate, and perform chain extension reaction at 50°C for 2h, wherein the addition amount of 2,2-dimethylol propionic acid in the whole system is 3.5wt%;

[0041] S13. Add hydroquinone and beta-hydroxyethyl methacrylate dropwise into the reaction system, heat to 45°C, perform end capping reaction, and then add TEA after cooling to perform neutralization, to obtain the aqueous polyurethane acrylate.

[0042] Example 4

[0043] The preparation method of the aqueous soft-chain polyurethane acrylate is as follows:

[0044] S11. Stir and mix isophorone diisocyanate, polyethylene glycol 6000 and dibutyltin dilaurate uniformly, then pass nitrogen gas and react at 50°C for 1.5h, wherein the initial molar ratio of -NCO and -OH functional groups is 4:1;

[0045] S12. 2,2-dimethylol propionic acid is dissolved in N,N-dimethylformamide, 1 drop of dibutyl tin dilaurate is added dropwise into the system of step S1, the dropping speed is controlled, the temperature is raised to 40°C, and the chain extension reaction is carried out for 2h, wherein the addition amount of 2,2-dimethylol propionic acid in the whole system is 3.6wt%;

[0046] S13. Hydroquinone and beta-hydroxyethyl methacrylate are added dropwise into the reaction system, the temperature is raised to 50°C, the end-capping reaction is carried out, TEA is added after cooling for neutralization, and the aqueous polyurethane acrylate is obtained.

[0047] Example 5

[0048] The preparation method of the aqueous hard-chain polyurethane acrylate is as follows:

[0049] S11. Isophorone diisocyanate, polyethylene glycol 200 and dibutyl tin dilaurate are stirred and mixed uniformly, then nitrogen is introduced, and the reaction is carried out at 55°C for 1h, wherein the initial molar ratio of -NCO and -OH functional groups is 2:1;

[0050] S12. 2,2-dimethylol propionic acid is dissolved in N,N-dimethylformamide, 1 drop of dibutyl tin dilaurate is added dropwise into the system of step S1, the dropping speed is controlled, the temperature is raised to 45°C, and the chain extension reaction is carried out for 1.5h, wherein the addition amount of 2,2-dimethylol propionic acid in the whole system is 3wt%;

[0051] S13. Hydroquinone and beta-hydroxyethyl methacrylate are added dropwise into the reaction system, the temperature is raised to 55°C, the end-capping reaction is carried out, TEA is added after cooling for neutralization, and the aqueous polyurethane acrylate is obtained.

[0052] Example 6

[0053] The preparation method of the aqueous hard-chain polyurethane acrylate is as follows:

[0054] S11. Isophorone diisocyanate, polyethylene glycol 300 and dibutyl tin dilaurate are stirred and mixed uniformly, then nitrogen is introduced, and the reaction is carried out at 50°C for 1h, wherein the initial molar ratio of -NCO and -OH functional groups is 3:1;

[0055] S12. 2,2-dimethylol propionic acid is dissolved in N,N-dimethylformamide, 1 drop of dibutyl tin dilaurate is added dropwise into the system of step S1, the dropping speed is controlled, the temperature is raised to 45°C, and the chain extension reaction is carried out for 1:h, wherein the addition amount of 2,2-dimethylol propionic acid in the whole system is 4wt%;

[0056] S13. Hydroquinone and beta-hydroxyethyl methacrylate are added dropwise to the reaction system, the temperature is raised to 55 DEG C, the end-capping reaction is carried out, TEA is added after cooling to neutralize, and the aqueous polyurethane acrylate is obtained.

[0057] Example 7

[0058] The preparation method of the aqueous hard-chain polyurethane acrylate is as follows:

[0059] S11. Isophorone diisocyanate, polyethylene glycol 400 and dibutyltin dilaurate are stirred and mixed uniformly, then nitrogen is introduced, and the reaction is carried out at 55 DEG C for 1.5 h, wherein the initial molar ratio of -NCO and -OH functional groups is 2:1;

[0060] S12. 2,2-dimethylol propionic acid is dissolved in N,N-dimethylformamide, 1 drop of dibutyltin dilaurate is added, the dropwise speed is controlled, and it is added dropwise to the system of step S1, the temperature is raised to 45 DEG C, and the chain extension reaction is carried out for 1.5 h, wherein the addition amount of 2,2-dimethylol propionic acid in the whole system is 3wt%;

[0061] S13. Hydroquinone and beta-hydroxyethyl methacrylate are added dropwise to the reaction system, the temperature is raised to 45 DEG C, the end-capping reaction is carried out, TEA is added after cooling to neutralize, and the aqueous polyurethane acrylate is obtained.

[0062] Example 8

[0063] A micro-nano surface structure anti-fouling self-cleaning coating, the coating comprises the following ingredients:

[0064]

[0065] The preparation method of the photocatalytic degradation particles comprises the following steps:

[0066] S21. The PS microspheres are dispersed into an ethanol aqueous solution containing cetyltrimethylammonium bromide, the concentration of cetyltrimethylammonium bromide is 0.3 mg / mL, the dispersion is uniformly stirred to obtain a dispersion liquid with a concentration of 0.1 mg / mL, ammonia water is added to the dispersion liquid, the volume concentration of ammonia water in the reaction system is 1vt%, stirring is continued, and finally tetrabutyl titanate is slowly added dropwise, the volume concentration of tetrabutyl titanate in the reaction system is 0.5vt%, the reaction is carried out at 60 DEG C for 2 h, the titanium dioxide precursor is obtained, the titanium dioxide precursor is calcined, the calcination temperature is 550 DEG C, the calcination time is 2 h, and the hollow mesoporous titanium dioxide is obtained.

[0067] S22. The soft-chain waterborne polyurethane acrylate prepared in Example 1 is added to water, stirred and dispersed uniformly, and the hollow mesoporous titanium dioxide prepared in step S11 is immersed in the polyurethane acrylate solution, immersed in a vacuum environment, the immersion time is 10 min, the vacuum degree is -0.1 MPa, to obtain titanium dioxide particles adsorbed with polyurethane acrylate;

[0068] S23. The nano-titanium dioxide is added to a sodium dodecyl sulfate aqueous solution, ultrasonically dispersed uniformly, then an initiator potassium persulfate is added, followed by the addition of methyl methacrylate, the mass ratio of methyl methacrylate to nano-titanium dioxide is 10:1, heated at 70°C for 15 h to obtain a poly-methyl methacrylate solution containing nano-titanium dioxide;

[0069] S24. The titanium dioxide particles adsorbed with polyurethane acrylate prepared in step S22 are added to the poly-methyl methacrylate solution containing nano-titanium dioxide prepared in step S23, so that the surface of the titanium dioxide particles adsorbed with polyurethane acrylate is coated with poly-methyl methacrylate, to obtain photocatalytic degradation particles.

[0070] Example 9

[0071] A micro-nano surface structure anti-fouling self-cleaning coating, the coating comprising the following ingredients:

[0072]

[0073] The preparation method of the photocatalytic degradation particles comprises the following steps:

[0074] S21. The PS microspheres are dispersed in an ethanol aqueous solution containing cetyltrimethylammonium bromide, the concentration of cetyltrimethylammonium bromide is 0.4 mg / mL, the dispersion liquid with a concentration of 0.2 mg / mL is obtained after stirring and dispersing uniformly, ammonia water is added to the dispersion liquid, the volume concentration of ammonia water in the reaction system is 2 vt%, continue to stir, and finally slowly add tetrabutyl titanate, the volume concentration of tetrabutyl titanate in the reaction system is 1 vt%, react at 50°C for 1 h to obtain a titanium dioxide precursor, the titanium dioxide precursor is calcined, the calcination temperature is 500°C, and the calcination time is 3 h to obtain hollow mesoporous titanium dioxide;

[0075] S22. The soft-chain waterborne polyurethane acrylate prepared in Example 2 is added to water, stirred and dispersed uniformly, and the hollow mesoporous titanium dioxide prepared in step S11 is immersed in the polyurethane acrylate solution, immersed in a vacuum environment, the immersion time is 20 min, the vacuum degree is -0.1 MPa, to obtain titanium dioxide particles adsorbed with polyurethane acrylate;

[0076] S23. Add nano-titanium dioxide into the aqueous solution of sodium dodecyl sulfate, uniformly disperse by ultrasonic, then add initiator potassium persulfate, and then add methyl methacrylate, the mass ratio of methyl methacrylate to nano-titanium dioxide is 10:2, heat at 80℃ for 10h to obtain a poly-methyl methacrylate solution containing nano-titanium dioxide;

[0077] S24. Add the titanium dioxide particles adsorbed with polyurethane acrylate prepared in step S22 into the poly-methyl methacrylate solution containing nano-titanium dioxide prepared in step S23 to coat the surface of the titanium dioxide particles adsorbed with polyurethane acrylate with poly-methyl methacrylate to obtain photocatalytic degradation particles.

[0078] Example 10

[0079] A micro-nano surface structure anti-fouling self-cleaning coating, the coating comprising the following ingredients:

[0080]

[0081] The preparation method of the photocatalytic degradation particles comprises the following steps:

[0082] S21. Disperse PS microspheres into an aqueous solution of ethanol containing cetyltrimethylammonium bromide, the concentration of cetyltrimethylammonium bromide is 0.35mg / mL, uniformly disperse by stirring to obtain a dispersion liquid with a concentration of 0.12mg / mL, add ammonia water into the dispersion liquid, the volume concentration of ammonia water in the reaction system is 1.4vt%, continue to stir, and finally slowly add tetrabutyl titanate, the volume concentration of tetrabutyl titanate in the reaction system is 0.9vt%, react at a constant temperature of 55℃ for 2h to obtain a titanium dioxide precursor, calcine the titanium dioxide precursor, the calcination temperature is 500℃, and the calcination time is 2h to obtain hollow mesoporous titanium dioxide;

[0083] S22. Add the soft-chain waterborne polyurethane acrylate prepared in Example 3 into water, uniformly disperse by stirring, immerse the hollow mesoporous titanium dioxide prepared in step S11 into the polyurethane acrylate solution in a vacuum environment, the immersion time is 10min, and the vacuum degree is -0.1MPa to obtain titanium dioxide particles adsorbed with polyurethane acrylate;

[0084] S23. Add nano-titanium dioxide into the aqueous solution of sodium dodecyl sulfate, uniformly disperse by ultrasonic, then add initiator potassium persulfate, and then add methyl methacrylate, the mass ratio of methyl methacrylate to nano-titanium dioxide is 10:2, heat at 80℃ for 10h to obtain a poly-methyl methacrylate solution containing nano-titanium dioxide;

[0085] S24. The titanium dioxide particles adsorbed with the polyurethane acrylate prepared in step S22 are added to the polymethyl acrylate solution containing nano-titanium dioxide prepared in step S23 to coat the surface of the titanium dioxide particles adsorbed with the polyurethane acrylate with polymethyl acrylate, thereby obtaining photocatalytic degradation particles.

[0086] Example 11

[0087] A micro-nano surface structure anti-fouling self-cleaning coating, comprising the following ingredients:

[0088]

[0089] The preparation method of the photocatalytic degradation particles comprises the following steps:

[0090] S21. The PS microspheres are dispersed in an ethanol aqueous solution containing cetyltrimethylammonium bromide, the concentration of the cetyltrimethylammonium bromide is 0.38 mg / mL, and after uniform stirring and dispersion, a dispersion liquid with a concentration of 0.16 mg / mL is obtained. Ammonia water is added to the dispersion liquid, the concentration of the ammonia water in the reaction system is 1.5 vt%, and stirring is continued. Finally, tetrabutyl titanate is slowly added dropwise, the volume concentration of the tetrabutyl titanate in the reaction system is 0.8 vt%, and the reaction is carried out at a constant temperature of 55℃ for 1 h, thereby obtaining a titanium dioxide precursor. The titanium dioxide precursor is calcined, the calcination temperature is 550℃, and the calcination time is 3 h, thereby obtaining hollow mesoporous titanium dioxide.

[0091] S22. The soft-chain waterborne polyurethane acrylate prepared in Example 1 is added to water, and after uniform stirring and dispersion, the hollow mesoporous titanium dioxide prepared in step S11 is immersed in the polyurethane acrylate solution. The immersion is carried out in a vacuum environment, the immersion time is 20 min, and the vacuum degree is -0.2 MPa, thereby obtaining titanium dioxide particles adsorbed with the polyurethane acrylate.

[0092] S23. Nano-titanium dioxide is added to a sodium dodecyl sulfate aqueous solution, and after ultrasonic dispersion, an initiator, potassium persulfate, is added, followed by the addition of methyl methacrylate. The mass ratio of the methyl methacrylate to the nano-titanium dioxide is 10:1.6, and the reaction is carried out at 75℃ for 12 h, thereby obtaining a polymethyl acrylate solution containing nano-titanium dioxide.

[0093] S24. The titanium dioxide particles adsorbed with the polyurethane acrylate prepared in step S22 are added to the polymethyl acrylate solution containing nano-titanium dioxide prepared in step S23 to coat the surface of the titanium dioxide particles adsorbed with the polyurethane acrylate with polymethyl acrylate, thereby obtaining photocatalytic degradation particles.

[0094] Comparative Example 1

[0095] A micro-nano surface structure anti-fouling self-cleaning coating, the coating comprises the following ingredients:

[0096]

[0097]

[0098] The preparation method of the photocatalytic degradation particle comprises the following steps:

[0099] S21. The PS microspheres are dispersed into an ethanol aqueous solution containing cetyltrimethylammonium bromide, the concentration of the cetyltrimethylammonium bromide is 0.38 mg / mL, after stirring and uniformly dispersing, a dispersion liquid with a concentration of 0.16 mg / mL is obtained, ammonia water is added into the dispersion liquid, the volume concentration of the ammonia water in the reaction system is 1.5 vt%, stirring is continued, and finally tetrabutyl titanate is slowly added dropwise, the volume concentration of the tetrabutyl titanate in the reaction system is 0.8 vt%, the reaction is carried out at a constant temperature of 55℃ for 1 h, a hollow mesoporous titanium dioxide is obtained by calcining the titanium dioxide precursor, the calcining temperature is 550℃, and the calcining time is 3 h;

[0100] S22. The soft-chain waterborne polyurethane acrylate prepared in Example 1 is added into water, stirring and uniformly dispersing, the hollow mesoporous titanium dioxide prepared in step S11 is immersed in the polyurethane acrylate solution, and the immersion is carried out in a vacuum environment, the immersion time is 20 min, and the vacuum degree is-0.2 MPa, thereby obtaining the titanium dioxide particles adsorbing the polyurethane acrylate;

[0101] S23. The nano-titanium dioxide is added into a sodium dodecyl sulfate aqueous solution, ultrasonic dispersion is carried out, after adding an initiator potassium persulfate, methyl methacrylate is added, the mass ratio of the methyl methacrylate to the nano-titanium dioxide is 10:1.6, and the reaction is carried out at 75℃ for 12 h, thereby obtaining the polymethyl methacrylate solution containing the nano-titanium dioxide;

[0102] S24. The titanium dioxide particles adsorbing the polyurethane acrylate prepared in step S22 are added into the polymethyl methacrylate solution containing the nano-titanium dioxide prepared in step S23, the surface of the titanium dioxide particles adsorbing the polyurethane acrylate is coated with the polymethyl methacrylate, and thereby the photocatalytic degradation particle is obtained.

[0103] Comparative Example 2

[0104] A micro-nano surface structure anti-fouling self-cleaning coating, the coating comprises the following ingredients:

[0105]

[0106] The preparation method of the photocatalytic degradation particle comprises the following steps:

[0107] S21. The PS microspheres are dispersed into an aqueous ethanol solution containing cetyltrimethylammonium bromide, the concentration of cetyltrimethylammonium bromide is 0.38 mg / mL, after stirring and uniformly dispersing, a dispersion liquid with a concentration of 0.16 mg / mL is obtained, ammonia water is added into the dispersion liquid, the volume concentration of ammonia water in the reaction system is 1.5 vt%, continue stirring, finally slowly add tetrabutyl titanate, the volume concentration of tetrabutyl titanate in the reaction system is 0.8 vt%, react at 55℃ for 1 h, obtain a titanium dioxide precursor, calcine the titanium dioxide precursor, the calcination temperature is 550℃, the calcination time is 3 h, obtain hollow mesoporous titanium dioxide;

[0108] S22. The soft-chain waterborne polyurethane acrylate prepared in Example 1 is added into water, stirred and uniformly dispersed, the hollow mesoporous titanium dioxide prepared in step S11 is immersed in the polyurethane acrylate solution, the immersion is carried out in a vacuum environment, the immersion time is 20 min, the vacuum degree is -0.2 MPa, obtain titanium dioxide particles adsorbed with polyurethane acrylate;

[0109] S23. After adding potassium persulfate into water, methyl methacrylate is added, heat at 75℃ for 12 h, obtain a polymethyl acrylate solution;

[0110] S24. The titanium dioxide particles adsorbed with polyurethane acrylate prepared in step S22 are added into the polymethyl acrylate solution prepared in step S23, the surface of the titanium dioxide particles adsorbed with polyurethane acrylate is coated with polymethyl acrylate, obtain photocatalytic degradation particles.

[0111] Comparative Example 3

[0112] A micro-nano surface structure anti-fouling self-cleaning coating, the coating comprises the following ingredients:

[0113]

[0114] The preparation method of the photocatalytic degradation particles comprises the following steps:

[0115] S21. The PS microspheres are dispersed into an aqueous ethanol solution containing cetyltrimethylammonium bromide, the concentration of cetyltrimethylammonium bromide is 0.38 mg / mL, after stirring and uniformly dispersing, a dispersion liquid with a concentration of 0.16 mg / mL is obtained, ammonia water is added into the dispersion liquid, the volume concentration of ammonia water in the reaction system is 1.5 vt%, continue stirring, finally slowly add tetrabutyl titanate, the volume concentration of tetrabutyl titanate in the reaction system is 0.8 vt%, react at 55℃ for 1 h, obtain a titanium dioxide precursor, calcine the titanium dioxide precursor, the calcination temperature is 550℃, the calcination time is 3 h, obtain hollow mesoporous titanium dioxide;

[0116] S22. The soft-chain waterborne polyurethane acrylate prepared in Example 1 was added to water and stirred to disperse uniformly. The hollow mesoporous titanium dioxide prepared in step S11 was immersed in the polyurethane acrylate solution under vacuum, the immersion time was 20 min, and the vacuum degree was -0.2 MPa, to obtain titanium dioxide particles adsorbed with polyurethane acrylate;

[0117] S23. Nano-titanium dioxide was added to an aqueous solution of sodium dodecyl sulfate and ultrasonically dispersed uniformly. After adding initiator potassium persulfate, methyl methacrylate was added, the mass ratio of methyl methacrylate to nano-titanium dioxide was 10:1.6, and the mixture was heated at 75°C for 12 h to obtain a poly(methyl methacrylate) solution containing nano-titanium dioxide.

[0118] S24. The titanium dioxide particles adsorbed with polyurethane acrylate prepared in step S22 were added to the poly(methyl methacrylate) solution containing nano-titanium dioxide prepared in step S23, so that the surface of the titanium dioxide particles adsorbed with polyurethane acrylate was coated with poly(methyl methacrylate), to obtain photocatalytic degradation particles.

[0119] Comparative Example 4

[0120] A micro-nano surface structure anti-fouling self-cleaning coating, the coating comprising the following ingredients:

[0121]

[0122] The preparation method of the photocatalytic degradation particles comprises the following steps:

[0123] S21. PS microspheres were dispersed in an aqueous solution of ethanol containing cetyltrimethylammonium bromide, the concentration of cetyltrimethylammonium bromide was 0.38 mg / mL, and the dispersion liquid with a concentration of 0.16 mg / mL was obtained after stirring and dispersing uniformly. Ammonia water was added to the dispersion liquid, the volume concentration of ammonia water in the reaction system was 1.5 vt%, and stirring was continued. Finally, tetrabutyl titanate was slowly added dropwise, the volume concentration of tetrabutyl titanate in the reaction system was 0.8 vt%, and the reaction was carried out at 55°C for 1 h to obtain a titanium dioxide precursor. The titanium dioxide precursor was calcined, the calcination temperature was 550°C, and the calcination time was 3 h to obtain hollow mesoporous titanium dioxide.

[0124] S22. The soft-chain waterborne polyurethane acrylate prepared in Example 1 was added to water and stirred to disperse uniformly. The hollow mesoporous titanium dioxide prepared in step S11 was immersed in the polyurethane acrylate solution under vacuum, the immersion time was 20 min, and the vacuum degree was -0.2 MPa, to obtain titanium dioxide particles adsorbed with polyurethane acrylate;

[0125] S23. The nano-titanium dioxide was added to the aqueous solution of sodium dodecyl sulfate, and ultrasonically dispersed uniformly. After adding the initiator potassium persulfate, methyl methacrylate was added, and the mass ratio of methyl methacrylate to nano-titanium dioxide was 10:1.6. The reaction was heated at 75°C for 12h to obtain a poly-methyl methacrylate solution containing nano-titanium dioxide;

[0126] S24. The titanium dioxide particles adsorbed with polyurethane acrylate prepared in step S22 were added to the poly-methyl methacrylate solution containing nano-titanium dioxide prepared in step S23 to coat the surface of the titanium dioxide particles adsorbed with polyurethane acrylate with poly-methyl methacrylate, thereby obtaining photocatalytic degradation particles.

[0127] The micro-nano surface structure anti-fouling self-cleaning coating prepared in the above examples and comparative examples was coated on a substrate, and the coating amount was 15g / m2, and the coating pass number was not limited. Finally, the coating composition was cured by UV irradiation, and the adhesion (coating film adhesion: determined according to ASTM D3359-09) and other test performances were tested respectively, and the results are shown in the following table. 2 , the coating pass number was not limited. Finally, the coating composition was cured by UV irradiation, and the adhesion (coating film adhesion: determined according to ASTM D3359-09) and other test performances were tested respectively, and the results are shown in the following table.

[0128]

[0129]

[0130] Obviously, the above examples are only examples for clearly illustrating, but not limitation to the embodiments. Based on the above description, other different forms of changes or variations can be made by those skilled in the art. Here, it is not necessary and impossible to enumerate all the embodiments. The obvious changes or variations derived therefrom are still within the protection scope of the present application.

Claims

1. A micro / nano surface structure antifouling self-cleaning coating, characterized in that: The coating contains the following components: Waterborne polyurethane acrylate A 25~35% Photocatalytic degradation of particles 10-20% Dispersant 1-2% Defoamer 1-2% 3-5% UV photoinitiator Adhesion promoter 0.4~1% Water balance; Wherein, the waterborne polyurethane acrylate A is a hard-chain polyurethane acrylate; the photocatalytic degradation particles are coated with waterborne polyurethane acrylate B, which is a soft-chain waterborne polyurethane acrylate. The method for preparing the photocatalytic degradation particles includes the following steps: S21. Disperse PS microspheres in an ethanol-water solution containing hexadecyltrimethylammonium bromide, stir and disperse evenly to obtain a dispersion, add ammonia to the dispersion, continue stirring, and finally slowly add tetrabutyl titanate, react at a constant temperature to obtain a titanium dioxide precursor, calcine the titanium dioxide precursor to obtain hollow mesoporous titanium dioxide. S22. Add soft-chain waterborne polyurethane acrylate to water, stir and disperse evenly, and impregnate the hollow mesoporous titanium dioxide prepared in step S11 into the polyurethane acrylate solution under vacuum to obtain titanium dioxide particles that adsorb polyurethane acrylate. S23. Add nano-titanium dioxide to an aqueous solution of sodium dodecyl sulfate, disperse it evenly by ultrasonication, add potassium persulfate as an initiator, add methyl methacrylate, heat and react to obtain a polymethyl methacrylate solution containing nano-titanium dioxide. S24. Add the titanium dioxide particles adsorbing polyurethane acrylate prepared in step S22 to the polymethyl methacrylate solution containing nano-titanium dioxide prepared in step S23, so that the surface of the titanium dioxide particles adsorbing polyurethane acrylate is coated with polymethyl methacrylate, and photocatalytic degradation particles are obtained.

2. The anti-fouling self-cleaning coating for micro / nano surface structures according to claim 1, characterized in that: The preparation method of the waterborne polyurethane acrylate is as follows: S11. After stirring and mixing isoflurone diisocyanate, diol and dibutyltin dilaurate evenly, nitrogen gas is introduced and the reaction is carried out at 50~60℃ for 1~2h, wherein the initial molar ratio of -NCO and -OH functional groups is 2~4:1; S12. Dissolve 2,2-dimethylolpropionic acid in N,N-dimethylformamide, add 1-2 drops of dibutyltin dilaurate dropwise into the system of step S1, and heat to 40-50℃ for chain extension reaction for 1-2 hours. The amount of 2,2-dimethylolpropionic acid added to the whole system is 3-4 wt%. S13. Hydroquinone and β-hydroxyethyl methacrylate were added dropwise to the reaction system, and the temperature was raised to 45~55℃ to carry out the end-capping reaction. After cooling, TEA was added for neutralization to obtain waterborne polyurethane acrylate.

3. The anti-fouling self-cleaning coating for micro / nano surface structures according to claim 2, characterized in that: The diol is polyethylene glycol. When the polyethylene glycol is selected from any one of polyethylene glycol 200, polyethylene glycol 300 or polyethylene glycol 400, a hard-chain waterborne polyurethane acrylate is obtained. When the polyethylene glycol is selected from any one of polyethylene glycol 1000, polyethylene glycol 2000, polyethylene glycol 4000 or polyethylene glycol 6000, a soft-chain waterborne polyurethane acrylate is obtained.

4. The anti-fouling self-cleaning coating for micro / nano surface structures according to claim 1, characterized in that: In S21, the concentration of PS microspheres in the dispersion is 0.1~0.2 mg / mL, the concentration of hexadecyltrimethylammonium bromide is 0.3~0.4 mg / mL, the concentration of ammonia is 1~2 vt%, and the concentration of tetrabutyl titanate is 0.5~1 vt.

5. The anti-fouling self-cleaning coating for micro / nano surface structures according to claim 1, characterized in that: The isothermal reaction in S21 is carried out at a temperature of 50-60℃ for 1-2 hours, and the calcination temperature is 500-550℃ for 2-3 hours.

6. The anti-fouling self-cleaning coating for micro / nano surface structures according to claim 1, characterized in that: The immersion time in S22 is 10-20 min, and the vacuum degree is -0.2~-0.1 MPa.

7. The anti-fouling self-cleaning coating for micro / nano surface structures according to claim 1, characterized in that: The mass ratio of S23 methyl methacrylate to nano titanium dioxide is 10:1~2, the heating reaction temperature is 70~80℃, and the time is 10~15h.

8. The method for preparing the anti-fouling self-cleaning coating with micro / nano surface structure according to claim 1, characterized in that, Includes the following steps: First, add the waterborne polyurethane acrylate to water and stir until it is evenly mixed. Then, add photocatalytic degradation particles, dispersant, defoamer, UV photoinitiator and adhesion promoter in sequence and stir until it is evenly mixed to obtain a micro-nano surface structure anti-fouling self-cleaning coating.

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