Preparation method of super-hydrophobic self-cleaning nano coating

Abstract

The invention relates to the technical field of nano material preparation, and discloses a preparation method of a super-hydrophobic self-cleaning nano coating, and the preparation method comprises the following steps: S1, dispersing nano silicon dioxide particles, nano zinc oxide particles and nano titanium dioxide particles in ethanol to prepare a suspension A, a suspension B and a suspension C; s2, adding a fluorine-containing silane coupling agent into the suspension A; s3, adding the suspension liquid B and the suspension liquid C; s4, centrifugally separating or filtering organic silicon resin and methylbenzene to collect a product; s5, re-dispersing in the organic solvent; s6, spraying, spin coating or dip coating; and S7, drying is conducted, and the nano coating with the super-hydrophobic self-cleaning performance is formed. The super-hydrophobic coating has excellent super-hydrophobic performance, effectively prevents adhesion and permeation of water on the surface, greatly improves the self-cleaning capability, has good antibacterial and anti-ultraviolet performance, has first-grade excellent adhesion and durability, and is not easy to fall off or damage.

Description

Technical Field

[0001] The invention relates to the technical field of nano material preparation, in particular to a method for preparing a super-hydrophobic self-cleaning nano coating. Background Art

[0002] With the continuous advancement of science and technology and the improvement of people's living standards, the requirements for material surface properties are becoming increasingly stringent. Among the many special performance requirements, materials with super-hydrophobic self-cleaning properties have attracted much attention and have broad application prospects in many fields such as construction, automobiles, medical treatment, and electronics.

[0003] Traditional material surfaces are often easily contaminated, and dirt, moisture and other contaminants easily adhere to their surfaces, which not only affects the appearance, but may also lead to performance degradation, increased maintenance costs, and the spread of bacteria and viruses. To solve these problems, researchers are committed to developing coatings with superhydrophobic self-cleaning properties.

[0004] Existing super-hydrophobic self-cleaning coating technologies have some limitations. Some preparation methods are complex and costly, making them difficult to mass produce and apply. Some coatings lack durability and stability, and are prone to losing their super-hydrophobic and self-cleaning properties after long-term use or in harsh environments. In addition, some coatings have relatively simple functions, and can only achieve simple hydrophobic and self-cleaning effects, which cannot meet increasingly diverse needs, such as having antibacterial and UV-resistant functions at the same time.

[0005] Therefore, there is an urgent need for an innovative, efficient and economical method for preparing superhydrophobic self-cleaning nanocoatings to overcome the shortcomings of existing technologies, meet higher requirements for material surface properties in different fields, and promote the development and progress of related industries. Summary of the invention

[0006] 1. Technical issues to be resolved

[0007] In view of the deficiencies in the prior art, the present invention provides a method for preparing a super-hydrophobic self-cleaning nano coating.

[0008] (II) Technical solution

[0009] A method for preparing a super-hydrophobic self-cleaning nano coating comprises the following steps:

[0010] S1, dispersing nano-silicon dioxide particles, nano-zinc oxide particles and nano-titanium dioxide particles in ethanol, and forming uniform suspensions A, B and C by ultrasonic treatment;

[0011] S2. Slowly drop a fluorinated silane coupling agent into the suspension A, and react for 30 to 60 minutes under stirring to obtain a mixed solution;

[0012] S3, adding suspension B and C to the above mixed solution, stirring evenly, and gradually adding deionized water and surfactant to form an emulsion system;

[0013] S4, adding silicone resin and toluene to the emulsion, stirring at high speed, and heating under reflux for 3 to 6 hours to promote the full reaction of the components. After the reaction is completed, cooling to room temperature, and collecting the product by centrifugation or filtration;

[0014] S5, re-dispersing the collected product in an organic solvent to form a coating solution;

[0015] S6, using a spray coating, spin coating or dip coating method to evenly coat the coating solution on the surface of the base material;

[0016] S7, drying the coated substrate at 60-80° C. to solidify the coating and form a nano coating with super hydrophobic self-cleaning properties.

[0017] Preferably, in step S1, the particle size of the nano silicon dioxide particles is 20-200 nm, the particle size of the nano zinc oxide particles is 20-30 nm, and the particle size of the nano titanium dioxide particles is 10-50 nm.

[0018] Preferably, in step S1, the mass ratio of nano-silicon dioxide particles, nano-zinc oxide particles and nano-titanium dioxide particles is 1:0.8-1.2:0.8-1.2, and the mass ratio of nano-silicon dioxide particles or nano-zinc oxide particles or nano-titanium dioxide particles to ethanol is 1:5-12.

[0019] Preferably, the fluorine-containing silane coupling agent in step S2 is heptadecafluorodecyl, the amount used is 10-20% of the mass of the suspension A, and the dropping speed is 1-2 mL / 3s.

[0020] Preferably, the surfactant in step S3 is sodium dodecylbenzene sulfonate, and the amount used is 2-5% of the mass of the mixed system.

[0021] Preferably, in step S4, the amount of the silicone resin used is 10-30% of the mass of the emulsion, and the amount of toluene used is 10-20% of the mass of the emulsion.

[0022] Preferably, in step S5, the organic solvent is ethanol or toluene, and the mass ratio of the product to the organic solvent is 1:3-10.

[0023] Preferably, in step S6, the substrate material is one of glass, stainless steel, wood, plastic, electronic components, clothing, and leather.

[0024] Preferably, the nano coating is used in construction, automobiles, medical treatment, electronics, clothing, and industry.

[0025] (III) Beneficial technical effects

[0026] The method for preparing the super-hydrophobic self-cleaning nano coating provided by the present invention has significant beneficial effects in many aspects.

[0027] First, by introducing multiple materials such as nano-silica, fluorinated silane coupling agent, nano-zinc oxide, nano-titanium dioxide, silicone resin, etc., the synergistic effect makes the coating have excellent super-hydrophobic properties, the water contact angle is significantly increased, and water droplets can easily roll off the surface, thereby effectively preventing the adhesion and penetration of water on the surface.

[0028] Secondly, the self-cleaning ability of the coating is greatly improved, which can easily remove attached dust, dirt and other pollutants, reducing the frequency and difficulty of cleaning work and saving manpower and material costs.

[0029] The addition of nano zinc oxide and nano titanium dioxide gives the coating good antibacterial and anti-ultraviolet properties. The antibacterial property can inhibit the growth and reproduction of bacteria and microorganisms, making the coating safer and more hygienic when used in medical, food and other fields; the anti-ultraviolet property can protect the coating and the base material from damage by ultraviolet rays and extend the service life.

[0030] The addition of silicone resin enhances the adhesion and durability of the coating, enabling it to maintain stable performance under long-term use and harsh environments, and is not easy to fall off or be damaged.

[0031] In addition, the preparation method is relatively simple in process, the material cost is low, and it is easy to achieve large-scale production, which is conducive to wide promotion and application.

[0032] In summary, the method for preparing a super-hydrophobic self-cleaning nano-coating of the present invention provides a high-performance, multifunctional and economical and practical solution for the relevant field, and has important application value and market prospects. DETAILED DESCRIPTION

[0033] Example 1

[0034] S1. Disperse 50 g of nano-silicon dioxide particles in 250 mL of ethanol, 40 g of nano-zinc oxide particles in 200 g of ethanol, and 40 g of nano-titanium dioxide particles in 200 g of ethanol, and form uniform suspensions A, B, and C by ultrasonic treatment.

[0035] S2. Slowly drop 30 g of fluorinated silane coupling agent heptadecafluorodecyl into suspension A at a dropping rate of 1 mL / 3 s, and react for 30 min under stirring to obtain a mixed solution.

[0036] S3. Add suspensions B and C to the above mixed solution, stir evenly, and gradually add 100 mL of deionized water and 20 g of surfactant sodium dodecylbenzene sulfonate to form an emulsion system.

[0037] S4. Add 100 g of silicone resin and 100 g of toluene to the emulsion, stir at high speed, and heat under reflux for 3 hours to promote the full reaction of the components. After the reaction is completed, cool to room temperature and collect the product by centrifugation or filtration.

[0038] S5. Take 200 g of the collected product and redisperse it in 600 mL of ethanol to form a coating solution.

[0039] S6. Use spraying, spin coating or dipping method to evenly coat the coating solution on the surface of the base material.

[0040] S7. Drying the coated substrate at 60° C. to solidify the coating and form a nano coating with super hydrophobic self-cleaning properties.

[0041] Example 2

[0042] S1. Disperse 50 g of nano-silicon dioxide particles in 600 mL of ethanol, 60 g of nano-zinc oxide particles in 600 g of ethanol, and 60 g of nano-titanium dioxide particles in 600 g of ethanol, and form uniform suspensions A, B, and C by ultrasonic treatment.

[0043] S2. Slowly drop 130 g of fluorine-containing silane coupling agent heptadecafluorodecyl into suspension A at a dropping rate of 2 mL / 3 s, and react for 60 min under stirring to obtain a mixed solution.

[0044] S3. Add suspensions B and C to the above mixed solution, stir evenly, and gradually add 500 mL of deionized water and 100 g of surfactant sodium dodecylbenzene sulfonate to form an emulsion system.

[0045] S4. Add 800 g of silicone resin and 500 g of toluene to the emulsion, stir at high speed, and heat under reflux for 6 hours to promote the full reaction of the components. After the reaction is completed, cool to room temperature and collect the product by centrifugation or filtration.

[0046] S5. Take 500 g of the collected product and redisperse it in 5000 mL of ethanol to form a coating solution.

[0047] S6. Use spraying, spin coating or dipping method to evenly coat the coating solution on the surface of the base material.

[0048] S7. Drying the coated substrate at 80° C. to solidify the coating and form a nano coating with super hydrophobic self-cleaning properties.

[0049] Example 3

[0050] S1. Disperse 50 g of nano-silicon dioxide particles in 300 mL of ethanol, 50 g of nano-zinc oxide particles in 300 g of ethanol, and 50 g of nano-titanium dioxide particles in 300 g of ethanol, and form uniform suspensions A, B, and C by ultrasonic treatment.

[0051] S2. Slowly drop 50 g of fluorinated silane coupling agent heptadecafluorodecyl into suspension A at a dropping rate of 1 mL / 3 s, and react for 40 min under stirring to obtain a mixed solution.

[0052] S3. Add suspensions B and C to the above mixed solution, stir evenly, and gradually add 200 mL of deionized water and 50 g of surfactant sodium dodecylbenzene sulfonate to form an emulsion system.

[0053] S4. Add 300 g of silicone resin and 200 g of toluene to the emulsion, stir at high speed, and heat under reflux for 5 hours to promote the full reaction of the components. After the reaction is completed, cool to room temperature and collect the product by centrifugation or filtration.

[0054] S5. Take 300 g of the collected product and redisperse it in 1000 mL of ethanol to form a coating solution.

[0055] S6. Use spraying, spin coating or dipping method to evenly coat the coating solution on the surface of the base material.

[0056] S7. Drying the coated substrate at 70° C. to solidify the coating and form a nano coating with super hydrophobic self-cleaning properties.

[0057] Example 4

[0058] S1. Disperse 50 g of nano-silicon dioxide particles in 400 mL of ethanol, 60 g of nano-zinc oxide particles in 400 g of ethanol, and 60 g of nano-titanium dioxide particles in 400 g of ethanol, and form uniform suspensions A, B, and C by ultrasonic treatment.

[0059] S2. Slowly drop 80 g of fluorine-containing silane coupling agent heptadecafluorodecyl into suspension A at a dropping speed of 2 mL / 3 s, and react for 50 min under stirring to obtain a mixed solution.

[0060] S3. Add suspensions B and C to the above mixed solution, stir evenly, and gradually add 400 mL of deionized water and 60 g of surfactant sodium dodecylbenzene sulfonate to form an emulsion system.

[0061] S4. Add 500 g of silicone resin and 300 g of toluene to the emulsion, stir at high speed, and heat under reflux for 5 hours to promote the full reaction of the components. After the reaction is completed, cool to room temperature and collect the product by centrifugation or filtration.

[0062] S5. Take 400 g of the collected product and redisperse it in 2000 mL of ethanol to form a coating solution.

[0063] S6. Use spraying, spin coating or dipping method to evenly coat the coating solution on the surface of the base material.

[0064] S7. Drying the coated substrate at 80° C. to solidify the coating and form a nano coating with super hydrophobic self-cleaning properties.

[0065] Example 5

[0066] S1. Disperse 50 g of nano-silicon dioxide particles in 500 mL of ethanol, 40 g of nano-zinc oxide particles in 500 g of ethanol, and 40 g of nano-titanium dioxide particles in 500 g of ethanol, and form uniform suspensions A, B, and C by ultrasonic treatment.

[0067] S2. Slowly drop 100 g of fluorine-containing silane coupling agent heptadecafluorodecyl into suspension A at a dropping rate of 1 mL / 3 s, and react for 50 min under stirring to obtain a mixed solution.

[0068] S3. Add suspensions B and C to the above mixed solution, stir evenly, and gradually add 500 mL of deionized water and 60 g of surfactant sodium dodecylbenzene sulfonate to form an emulsion system.

[0069] S4. Add 600 g of silicone resin and 400 g of toluene to the emulsion, stir at high speed, and heat under reflux for 5 hours to promote the full reaction of the components. After the reaction is completed, cool to room temperature and collect the product by centrifugation or filtration.

[0070] S5. Take 400 g of the collected product and redisperse it in 3000 mL of ethanol to form a coating solution.

[0071] S6. Use spraying, spin coating or dipping method to evenly coat the coating solution on the surface of the base material.

[0072] S7. Drying the coated substrate at 60° C. to solidify the coating and form a nano coating with super hydrophobic self-cleaning properties.

[0073] Comparative Example 1: No suspension A was added, and the rest of the process was the same as in Example 1.

[0074] Comparative Example 2: No suspension B was added, and the rest of the process was the same as in Example 1.

[0075] Comparative Example 3: No suspension C was added, and the rest of the process was the same as in Example 1.

[0076] Comparative Example 4: No suspensions B and C were added, and the remaining processes were the same as those in Example 1.

[0077] Comparative Example 5: No silicone resin was added, and the rest of the process was the same as that of Example 1.

[0078] Performance Test:

[0079] 1. Hydrophobicity test: The contact angle and rolling angle of the coating surfaces of Examples 1 to 5 and Comparative Examples 1 to 3 were tested using a water drop angle tester. Five different positions were taken for each sample and the average value was calculated. The results are shown in Table 1.

[0080] Table 1

[0081]

[0082]

[0083] As shown in Table 1, the contact angles of Examples 1 to 5 are greater than that of Comparative Example 1, all being above 150°, and the rolling angles are less than that of Comparative Example 1. Nano-silicon dioxide particles, nano-zinc oxide particles, and nano-titanium dioxide particles are added, and the coating has good hydrophobicity.

[0084] 2. Anti-ultraviolet test: The coatings of Examples 1 to 5 and Comparative Example 4 were sprayed on a glass slide of size 60 mm × 60 mm × 0.5 mm, dried at a constant temperature of 60°C, and the light transmittance of different samples was measured at 300 nm, 360 nm and 560 nm using an ultraviolet spectrophotometer. The test results are shown in Table 2.

[0085] Table 2

[0086] Group 300nm transmittance% 360nm transmittance% 560nm transmittance% Example 1 2.5 4.2 5.8 Example 2 2.3 3.8 6.1 Example 3 2.6 4.0 5.7 Example 4 2.3 4.0 5.7 Example 5 2.2 4.1 5.9 Comparative Example 4 32.5 42.3 54.8

[0087] It can be seen from Table 2 that the light transmittance of Examples 1 to 5 is much lower than that of Comparative Example 4. The addition of nano zinc oxide particles and nano titanium dioxide particles greatly enhances the UV resistance of the coating.

[0088] 3. Antibacterial test: Examples 1 to 5 and Comparative Example 4 were tested according to GB / T 21866-2008 standard. The results are shown in Table 3.

[0089] Table 3

[0090]

[0091]

[0092] It can be seen from Table 3 that the antibacterial rates of Examples 1 to 5 are greater than that of Comparative Example 4. The addition of nano zinc oxide particles and nano titanium dioxide particles effectively improves the antibacterial effect of the coating.

[0093] 4. Adhesion test: The cross-hatch method was used as the test method. According to GB / T9286-2021, the coatings prepared in Examples 1 to 5 and Comparative Example 5 were coated on a 200 mm × 200 mm × 10 mm carbon steel plate for testing. The 6 × 6 cutting method was adopted. Three parts of the coating of each sample were selected to make cutting samples. The overall situation was observed, and the adhesion index of the coating was evaluated according to the standard. The results are shown in Table 4.

[0094] Table 4

[0095]

[0096] It can be seen from Table 4 that the adhesion of the coatings prepared in Examples 1 to 5 is greater than that in Comparative Example 5, and the addition of silicone resin can effectively improve the adhesion effect of the coatings.

[0097] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation methods described. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

[0098] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a super-hydrophobic self-cleaning nano coating, characterized in that: The steps include: S1, dispersing nano-silicon dioxide particles, nano-zinc oxide particles and nano-titanium dioxide particles in ethanol, and forming uniform suspensions A, B and C by ultrasonic treatment; S2. Slowly drop a fluorinated silane coupling agent into the suspension A and react for 30 to 60 minutes under stirring to obtain a mixed solution; S3, adding suspension B and C to the above mixed solution, stirring evenly, and gradually adding deionized water and surfactant to form an emulsion system; S4, adding silicone resin and toluene to the emulsion, stirring at high speed, and heating under reflux for 3 to 6 hours to promote the full reaction of the components. After the reaction is completed, cooling to room temperature, and collecting the product by centrifugation or filtration; S5, re-dispersing the collected product in an organic solvent to form a coating solution; S6, using a spray coating, spin coating or dip coating method to evenly coat the coating solution on the surface of the base material; S7. Drying the coated substrate at 60-80° C. to solidify the coating and form a nano-coating with super-hydrophobic self-cleaning properties.

2. The method for preparing a super-hydrophobic self-cleaning nano coating according to claim 1, characterized in that: In the step S1, the particle size of the nano silicon dioxide particles is 20-200 nm, the particle size of the nano zinc oxide particles is 20-30 nm, and the particle size of the nano titanium dioxide particles is 10-50 nm.

3. The method for preparing a super-hydrophobic self-cleaning nano coating according to claim 1, characterized in that: In the step S1, the mass ratio of the nano-silicon dioxide particles, the nano-zinc oxide particles and the nano-titanium dioxide particles is 1:0.8-1.2:0.8-1.2, and the mass ratio of the nano-silicon dioxide particles or the nano-zinc oxide particles or the nano-titanium dioxide particles to ethanol is 1:5-12.

4. The method for preparing a super-hydrophobic self-cleaning nano coating according to claim 1, characterized in that: In step S2, the fluorine-containing silane coupling agent is heptadecafluorodecyl, the amount used is 10-20% of the mass of the suspension A, and the dropping speed is 1-2 mL / 3s.

5. The method for preparing a super-hydrophobic self-cleaning nano coating according to claim 1, characterized in that: In step S3, the surfactant is sodium dodecylbenzene sulfonate, and the amount used is 2-5% of the mass of the mixed system.

6. The method for preparing a super-hydrophobic self-cleaning nano coating according to claim 1, characterized in that: In the step S4, the amount of the silicone resin used is 10-30% of the mass of the emulsion, and the amount of toluene used is 10-20% of the mass of the emulsion.

7. The method for preparing a super-hydrophobic self-cleaning nano coating according to claim 1, characterized in that: In step S5, the organic solvent is ethanol or toluene, and the mass ratio of the product to the organic solvent is 1:3-10.

8. The method for preparing a super-hydrophobic self-cleaning nano coating according to claim 1, characterized in that: In step S6, the substrate material is one of glass, stainless steel, wood, plastic, electronic components, clothing, and leather.

9. The nanocoating prepared by the method for preparing a super-hydrophobic self-cleaning nanocoating according to claim 1, characterized in that: The nano coating is used in construction, automobiles, medical treatment, electronics, clothing and industry.

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