Super-hydrophobic nanosilica and a method for preparing the same

Abstract

The application provides super-hydrophobic nano-silica and a preparation method thereof, and belongs to the technical field of nano materials. 3-mercapto propyl triethoxysilane and methyl methacrylate dodecafluoroheptyl ester are used to synthesize F-MPTS through a click reaction of mercapto olefin; meanwhile, the surface of nano-silica is modified through a hydrolysis condensation reaction of 3-mercapto propyl triethoxysilane and F-MPTS; wherein, the 3-mercapto propyl triethoxysilane can improve the corrosion resistance and oxidation resistance of nano-silica; the F-MPTS contains fluorine atoms, the fluorine atoms have a low surface energy and a tendency to migrate to the surface of air, so that the hydrophobicity of nano-silica is improved. The modified nano-silica obtained finally has super-hydrophobicity, can be widely used in surface modification of various materials and coatings, makes the materials and coatings have super-hydrophobicity and excellent self-cleaning ability, and can effectively protect the materials and coatings.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of nanomaterials, in particular to a kind of superhydrophobic nanosilica and preparation method thereof. BACKGROUND

[0002] Nanosilica, commonly known as white carbon black, is amorphous white powder, non-toxic, odorless, non-polluting, microstructure is spherical, presents flocculation and network quasi-particle structure, insoluble in water. The size range is 1-100 nm, so it has many unique properties, such as optical properties against ultraviolet light, can improve the aging resistance, strength and chemical resistance of other materials, and has very wide application. However, ordinary nanosilica does not have hydrophobic property, and needs to be modified to have good hydrophobic or superhydrophobic property.

[0003] At present, the common modification method of silica is wet modification, that is, nanosilica substrate is first dispersed in liquid, and then other operations are carried out. A large amount of organic auxiliary agent needs to be added to ensure the obtainment of superhydrophobic effect, and long time high-temperature holding operation is needed, and the subsequent treatment process is more, the energy consumption is larger, which cannot meet the continuity requirement of industrialized mass production.

[0004] Therefore, it is urgent to provide a preparation method of modified silica, which has simple preparation process, mild reaction condition and no too complex post-treatment process. The modified silica obtained by the method has nanoscale particle size and has superhydrophobic effect. SUMMARY

[0005] In view of this, the purpose of the present application is to provide a preparation method of superhydrophobic nanosilica. The superhydrophobic nanosilica obtained by the preparation method has particle size concentrated in 5-20 nm, and has good hydrophobic effect not only on water but also on some water-soluble beverages and dyes.

[0006] In order to achieve the above-mentioned purpose of the application, the present application provides the following technical scheme:

[0007] The present application provides a preparation method of superhydrophobic nanosilica, comprising the following steps:

[0008] (1) mixing 3-mercaptopropyltriethoxysilane, methyl methacrylate dodecafluoroheptyl ester, a first organic solvent and a first organic base to carry out click reaction, to obtain F-MPTS;

[0009] (2) mixing tetraethyl silicate, a second organic solvent, deionized water and a second organic base to carry out hydrolysis reaction, to obtain nanosilica suspension;

[0010] (3) adding 3-mercaptopropyl triethoxysilane and F-MPTS obtained in the step (1) into the nanometer silica suspension obtained in the step (2) to perform a hydrolytic condensation reaction, thereby obtaining super-hydrophobic nanometer silica.

[0011] Preferably, the first organic solvent in the step (1) and the second organic solvent in the step (2) independently comprise ethanol and / or methanol.

[0012] Preferably, the first organic base in the step (1) and the second organic base in the step (2) independently comprise triethylamine and / or ammonia.

[0013] Preferably, the ratio of the amount of substance of 3-mercaptopropyl triethoxysilane to the amount of substance of methacrylic acid dodecafluoroheptyl ester in the step (1) is 1:1-1:1.5.

[0014] Preferably, the temperature of the click reaction in the step (1) is room temperature, and the time of the click reaction is 3-12h.

[0015] Preferably, the ratio of the amount of substance of tetraethyl orthosilicate to the amount of substance of deionized water in the step (2) is 1:10-1:1; the ratio of the amount of substance of deionized water to the amount of substance of the second organic base is 10:1-1:1; and the amount of the second organic solvent is 80%-99% of the total mass of the second organic solvent, deionized water and the second organic base.

[0016] Preferably, the temperature of the hydrolysis reaction in the step (2) is 40-80℃, and the time of the hydrolysis reaction is 0.5-5h.

[0017] Preferably, the ratio of the amount of substance of 3-mercaptopropyl triethoxysilane to the amount of substance of tetraethyl orthosilicate in the step (2) is 1:5-1:1; and the amount of F-MPTS is 15%-80% of the sum of the mass of 3-mercaptopropyl triethoxysilane and F-MPTS.

[0018] Preferably, the temperature of the hydrolytic condensation reaction in the step (3) is 40-80℃, and the time of the hydrolytic condensation reaction is 1-6h.

[0019] The application also provides super-hydrophobic nanometer silica prepared by the preparation method described in the above scheme.

[0020] The application provides a preparation method of super-hydrophobic nano-silica, comprising the following steps: mixing 3-mercaptopropyl triethoxysilane, methyl methacrylate dodecafluoroheptyl ester, a first organic solvent and a first organic base to perform a click reaction to obtain F-MPTS; mixing tetraethyl silicate, a second organic solvent, deionized water and a second organic base to perform a hydrolysis reaction to obtain a nano-silica suspension; adding 3-mercaptopropyl triethoxysilane and F-MPTS into the nano-silica suspension to perform a hydrolysis condensation reaction to obtain super-hydrophobic nano-silica. The methyl methacrylate dodecafluoroheptyl ester is grafted onto the 3-mercaptopropyl triethoxysilane through the click reaction to obtain the F-MPTS; meanwhile, the surface of the nano-silica is modified through the hydrolysis condensation reaction of the 3-mercaptopropyl triethoxysilane and the F-MPTS; wherein the 3-mercaptopropyl triethoxysilane can improve the corrosion resistance and oxidation resistance of the nano-silica; the F-MPTS contains fluorine atoms, the fluorine atoms have a low surface energy and a tendency to migrate to the surface of air, so that the hydrophobicity of the nano-silica is improved; meanwhile, the nano-silica has a large specific surface area due to the nano structure, so that more fluorine atoms can be gathered on the surface of the nano-silica, so that the surface energy is further reduced, and the hydrophobic effect of the nano-silica is further improved; finally, the nano-silica is modified by the 3-mercaptopropyl triethoxysilane and the F-MPTS, and the super-hydrophobic nano-silica obtained has a good hydrophobic effect not only on water but also on some water-soluble beverages and dyes, and can be widely used in the surface modification of various materials and coatings to make the materials and coatings have super-hydrophobic properties and excellent self-cleaning ability, and can effectively protect the materials and coatings. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 A roadmap of the preparation method of the super-hydrophobic nano-silica provided by the application;

[0022] Figure 2 A water contact angle diagram of the super-hydrophobic nano-silica provided by the embodiments 1-3 of the application;

[0023] Figure 3 A TEM diagram of the super-hydrophobic nano-silica prepared in the embodiment 1 of the application;

[0024] Figure 4 A particle size distribution diagram of the super-hydrophobic nano-silica prepared in the embodiment 1 of the application;

[0025] Figure 5 A hydrophobic property test diagram of the nano-silica prepared in the comparative example 1 of the application;

[0026] Figure 6 A hydrophobic property test diagram of the purchased nano-silica;

[0027] Figure 7 The hydrophobic performance test diagram of the super-hydrophobic nanosilica prepared for the embodiment 1 of the present application;

[0028] Figure 8 The hydrophobic performance test diagram of the super-hydrophobic nanosilica prepared for the embodiment 1 of the present application;

[0029] Figure 9 The hydrophobic performance test diagram of the super-hydrophobic nanosilica prepared for the embodiment 1 of the present application;

[0030] Figure 10 The hydrophobic performance test diagram of the super-hydrophobic nanosilica prepared for the embodiment 1 of the present application. DETAILED DESCRIPTION

[0031] The present application provides a preparation method of super-hydrophobic nanosilica, comprising the following steps:

[0032] (1) mixing 3-mercaptopropyl triethoxysilane, methyl methacrylate dodecafluoroheptyl ester, a first organic solvent and a first organic base to perform a click reaction to obtain F-MPTS;

[0033] (2) mixing tetraethyl silicate, a second organic solvent, deionized water and a second organic base to perform a hydrolysis reaction to obtain a nanosilica suspension;

[0034] (3) adding 3-mercaptopropyl triethoxysilane and the F-MPTS obtained in the step (1) into the nanosilica suspension obtained in the step (2) to perform a hydrolysis condensation reaction to obtain super-hydrophobic nanosilica.

[0035] The present application mixes 3-mercaptopropyl triethoxysilane, methyl methacrylate dodecafluoroheptyl ester, a first organic solvent and a first organic base to perform a click reaction to obtain F-MPTS.

[0036] In the present application, the first organic solvent preferably comprises ethanol and / or methanol, and more preferably is ethanol. The present application can reduce the toxicity of the solvent and improve the safety of the operation by selecting ethanol as the solvent for the click reaction.

[0037] In the present application, the first organic base preferably comprises triethylamine and / or ammonia water, and more preferably is triethylamine. The present application preferably uses triethylamine as the catalyst for the click reaction, which can avoid the volatilization of ammonia water during the reaction.

[0038] In the present application, the ratio of the substance amount of the 3-mercaptopropyl triethoxysilane and the methacrylic acid dodecafluoroheptyl ester is preferably 1:1 to 1:1.5, and more preferably 1:1 to 1:1.2. The present application limits the use amount of the 3-mercaptopropyl triethoxysilane and the methacrylic acid dodecafluoroheptyl ester to the above range, which is beneficial to the sufficient reaction of the 3-mercaptopropyl triethoxysilane.

[0039] In the present application, the use amount of the first organic base is preferably 0.1% to 0.5% of the total mass of the 3-mercaptopropyl triethoxysilane and the methacrylic acid dodecafluoroheptyl ester.

[0040] The present application does not have special provisions for the use amount of the first organic solvent, and the required solvent amount can be added according to the conventional chemical reaction.

[0041] In the present application, the temperature of the click reaction is preferably room temperature. In the present application, the time of the click reaction is preferably 3 to 12 hours, and more preferably 5 to 12 hours. The present application does not have special provisions for the room temperature, that is, the reaction does not need to be heated, nor does it need to be cooled, and it can be carried out at room temperature. The present application limits the temperature and time of the click reaction to the above range, which can realize the sufficient progress of the click reaction.

[0042] After the completion of the click reaction, the present application preferably performs rotary evaporation on the product of the click reaction. The present application does not have special provisions for the rotary evaporation method, and the rotary evaporation method well known to those skilled in the art can be used to remove volatile reagents. The present application removes the first organic solvent and the first base in the system after the click reaction by using the rotary evaporation method.

[0043] The present application mixes tetraethyl silicate, a second organic solvent, deionized water, and a second organic base to perform a hydrolysis reaction, thereby obtaining a nano-silica suspension.

[0044] The present application preferably mixes the second organic solvent, the deionized water, and the second organic base first, and then adds tetraethyl silicate to perform a hydrolysis reaction, thereby obtaining a nano-silica suspension. The present application mixes the second organic solvent, the deionized water, and the second organic base first, which is to prepare for the hydrolysis reaction of tetraethyl silicate.

[0045] The present application does not have special provisions for the mixing method, and a mixing method well known to those skilled in the art can be used to realize uniform mixing of materials. In the present application, the temperature of the mixing is preferably 40 to 80°C, and more preferably 60 to 80°C; and the time of the mixing is preferably 5 to 30 minutes, and more preferably 20 to 30 minutes. The present application limits the temperature and time of the mixing to the above range, which is beneficial to the sufficient mixing of materials.

[0046] In the present application, the second organic solvent preferably comprises ethanol and / or methanol, and more preferably ethanol. The present application can reduce the toxicity of the solvent and improve the safety of operation by selecting ethanol as the solvent for the hydrolysis reaction.

[0047] In the present application, the second organic base preferably comprises triethylamine and / or ammonia, and more preferably ammonia. In the present application, ammonia is easily soluble in water, which can promote the hydrolysis reaction of tetraethyl orthosilicate.

[0048] In the present application, the molar ratio of tetraethyl orthosilicate to deionized water is preferably 1:10 to 1:1, and more preferably 1:9 to 1:1. In the present application, the molar ratio of deionized water to the second organic base is preferably 10:1 to 1:1, and more preferably 9:1 to 1:1. In the present application, the amount of the second organic solvent is preferably 80% to 99% of the total mass of the second organic solvent, deionized water, and the second organic base, and more preferably 85% to 99%. The present application can effectively control the particle size of the prepared nano-silica by controlling the amount of deionized water.

[0049] In the present application, the hydrolysis reaction is preferably carried out under stirring. The temperature of the hydrolysis reaction is preferably 40 to 80°C, and more preferably 60°C. The time of the hydrolysis reaction is preferably 0.5 to 5 hours, and more preferably 1 to 5 hours. The present application limits the temperature and time of the hydrolysis reaction within the above ranges, which is conducive to the full conversion of tetraethyl orthosilicate to nano-silica.

[0050] After obtaining the nano-silica suspension, the present application adds 3-mercaptopropyl triethoxysilane and the F-MPTS to the nano-silica suspension to carry out a hydrolysis condensation reaction, thereby obtaining super-hydrophobic nano-silica.

[0051] In the present application, the molar ratio of 3-mercaptopropyl triethoxysilane to tetraethyl orthosilicate in the hydrolysis reaction is preferably 1:5 to 1:1, and more preferably 1:4 to 1:1. In the present application, the amount of F-MPTS is preferably 15% to 80% of the sum of the mass of 3-mercaptopropyl triethoxysilane and F-MPTS, and more preferably 20% to 80%. The present application limits the amount of 3-mercaptopropyl triethoxysilane and F-MPTS within the above ranges, and the obtained super-hydrophobic nano-silica has excellent hydrophobic properties.

[0052] In the present application, the second organic solvent can be supplemented as needed in the hydrolysis condensation reaction. The present application does not have special provisions for the amount of the second organic solvent to be supplemented, as long as the modifier 3-mercaptopropyl triethoxysilane and F-MPTS can be fully dissolved in the reaction system.

[0053] In the present application, the hydrolytic condensation reaction is preferably carried out under stirring. In the present application, the temperature of the hydrolytic condensation reaction is preferably 40-80℃, more preferably 50-80℃; the time of the hydrolytic condensation reaction is preferably 1-6h, more preferably 2-6h. The present application realizes the modification of nano-silica by 3-mercaptopropyl triethoxysilane and F-MPTS through the hydrolytic condensation reaction.

[0054] After the hydrolytic condensation reaction, the present application preferably sequentially carries out drying, grinding and screening on the product of the hydrolytic condensation reaction to obtain the super-hydrophobic nano-silica.

[0055] The present application does not have special provisions for the drying mode, and the solvent in the product can be removed. In the present application, the temperature of the drying is preferably 40-80℃, more preferably 50-80℃. The present application does not have special provisions for the time of the drying, and the solvent in the product can be removed.

[0056] The present application does not have special provisions for the grinding mode, and the hydrolytic condensation reaction product after drying can be ground into powder by using the grinding mode well known to those skilled in the art.

[0057] The present application does not have special provisions for the screening mode, and the screening mode can be achieved by using the conventional screen filtering mode. In the present application, the aperture of the screen is preferably 50-200 mesh, more preferably 100 mesh. The present application avoids obtaining the super-hydrophobic nano-silica with too large particle size by the screening mode.

[0058] The present application also provides the super-hydrophobic nano-silica prepared by the preparation method described in the above scheme. The super-hydrophobic nano-silica provided by the present application not only has good hydrophobic effect on water, but also has good hydrophobic effect on some water-soluble beverages, dyes and the like, and can be widely used in the surface modification of various materials and coatings to make them have super-hydrophobic performance and endow them with excellent self-cleaning ability, and can also effectively protect the materials and coatings.

[0059] The route map of the preparation method of the super-hydrophobic nano-silica provided by the present application is shown in Figure 1 , the first step: 3-mercaptopropyl triethoxysilane and methacrylic acid dodecafluoroheptyl ester are subjected to click reaction to obtain F-MPTS; the second step: tetraethyl silicate is hydrolyzed to obtain nano-silica; the third step: 3-mercaptopropyl triethoxysilane and F-MPTS are used to modify the nano-silica by hydrolytic condensation reaction to obtain super-hydrophobic nano-silica.

[0060] The technical solutions in the present application will be clearly and completely described below in combination with the embodiments in the present application. Apparently, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative effort belong to the protection scope of the present application.

[0061] Embodiment 1

[0062] A preparation method of super-hydrophobic nano-silica, comprising the following steps:

[0063] (1) 11.92 g of 3-mercaptopropyl triethoxysilane, 20.01 g of methacrylic acid dodecafluoroheptyl ester, 25.60 g of ethanol and 0.15 g of triethylamine are sequentially added into a three-necked flask, and stirring is performed at room temperature for 5 h to perform a click reaction, then rotary evaporation treatment is performed to remove the ethanol and triethylamine, and F-MPTS is obtained;

[0064] (2) 61.05 g of ethanol, 1.81 g of deionized water and 0.78 g of ammonia water are first added into a three-necked flask, stirring is performed at 60 DEG C for 20 min, then 10.77 g of tetraethyl silicate is added, the temperature is kept unchanged, and stirring is continuously performed for 1.5 h to perform a hydrolysis reaction, and a nano-silica suspension is obtained;

[0065] (3) 20.99 g of ethanol, 4.77 g of 3-mercaptopropyl triethoxysilane and 1.00 g of F-MPTS are added into the nano-silica suspension obtained in the step (2), and stirring is continuously performed at 60 DEG C for 3 h to perform a hydrolysis condensation reaction; then the hydrolysis condensation reaction product is placed in an oven at 50 DEG C for drying, then grinding is performed to obtain a powder, and the powder is sieved by using a 100-mesh sieve, and super-hydrophobic nano-silica is obtained, which is recorded as sample No. 1.

[0066] Embodiment 2

[0067] A preparation method of super-hydrophobic nano-silica, comprising the following steps:

[0068] (1) 11.92 g of 3-mercaptopropyl triethoxysilane, 20.01 g of methacrylic acid dodecafluoroheptyl ester, 25.60 g of ethanol and 0.15 g of triethylamine are sequentially added into a three-necked flask, and stirring is performed at room temperature for 5 h to perform a click reaction, then rotary evaporation treatment is performed to remove the ethanol and triethylamine, and F-MPTS is obtained;

[0069] (2) 63.45 g of ethanol, 1.87 g of deionized water and 0.74 g of ammonia water are first added into a three-necked flask, stirring is performed at 60 DEG C for 20 min, then 10.74 g of tetraethyl silicate is added, the temperature is kept unchanged, and stirring is continuously performed for 1.5 h to perform a hydrolysis reaction, and a nano-silica suspension is obtained;

[0070] (3) To the nanosilica suspension obtained in step (2), 17.70 g of ethanol was added, and 4.58 g of 3-mercaptopropyl triethoxysilane and 2.80 g of F-MPTS were added, and the hydrolysis and condensation reaction was continued at 60°C for 3 h under stirring; then the product of the hydrolysis and condensation reaction was placed in an oven at 50°C for drying, then ground into powder, and sieved with a 100-mesh sieve, to obtain the super-hydrophobic nanosilica, which was marked as sample No. 2.

[0071] Example 3

[0072] A method for preparing super-hydrophobic nanosilica, comprising the following steps:

[0073] (1) 3-mercaptopropyl triethoxysilane, dodecafluoroheptyl methacrylate, ethanol and triethylamine were sequentially added to a three-necked flask, and the click reaction was carried out under stirring at room temperature for 5 h, and then the ethanol and triethylamine were removed by rotary evaporation to obtain F-MPTS;

[0074] (2) 63.25 g of ethanol, 1.81 g of deionized water and 0.76 g of ammonia were first added to a three-necked flask, and stirred at 60°C for 20 min, then 10.82 g of tetraethyl orthosilicate was added, and the temperature was kept unchanged, and the hydrolysis reaction was continued for 1.5 h under stirring to obtain a nanosilica suspension;

[0075] (3) To the nanosilica suspension obtained in step (2), 16.99 g of ethanol was added, and 4.48 g of 3-mercaptopropyl triethoxysilane and 4.96 g of F-MPTS were added, and the hydrolysis and condensation reaction was continued at 60°C for 3 h under stirring, then the product of the hydrolysis and condensation reaction was placed in an oven at 50°C for drying, then ground into powder, and sieved with a 100-mesh sieve, to obtain the super-hydrophobic nanosilica, which was marked as sample No. 3.

[0076] Comparative Example 1

[0077] A method for preparing nanosilica, comprising the following steps: 63.25 g of ethanol, 1.81 g of deionized water and 0.76 g of ammonia were first added to a three-necked flask, and stirred at 60°C for 20 min, then 10.82 g of tetraethyl orthosilicate was added, and the temperature was kept unchanged, and the hydrolysis reaction was continued for 1.5 h under stirring to obtain nanosilica.

[0078] Performance test

[0079] The water contact angle of the super-hydrophobic nanosilica prepared in Examples 1-3 was tested according to the contact angle test standard GB / T 14210, and the specific results are shown in Table 1. Figure 2From Figure 2 It can be seen that the water contact angle gradually increases with the increase of the F-MPTS addition amount.

[0080] The super-hydrophobic nanometer silicon dioxide prepared in Example 1 is subjected to transmission electron microscope test, and the test result is shown in Table 1. Figure 3 From Figure 3 It can be seen that the obtained super-hydrophobic nanometer silicon dioxide is in the form of small globules after dilution and dispersion.

[0081] The super-hydrophobic nanometer silicon dioxide prepared in Example 1 is subjected to particle size distribution test, and the test result is shown in Table 2. Figure 4 From Figure 4 It can be seen that the particle size of the obtained super-hydrophobic nanometer silicon dioxide is concentrated in 5-20nm.

[0082] The nanometer silicon dioxide prepared in Comparative Example 1, the nanometer silicon dioxide directly purchased and the super-hydrophobic nanometer silicon dioxide prepared in Example 1 are uniformly spread on the glass sheet with double-sided adhesive to be fixed, and an appropriate amount of water (Coke, amaranth solution, crystal violet solution) is taken by a rubber head dropper and dropped on the surface to directly test the hydrophobic performance, and the test result is shown in Table 3. Figures 5-10 .

[0083] From Figure 5 and Figure 6 It can be seen that the nanometer silicon dioxide prepared in Comparative Example 1 and the nanometer silicon dioxide with a particle size of 40nm purchased from Shanghai Maikelin Biochemical Technology Co., Ltd. immediately absorb the water droplets, and do not have hydrophobic effect.

[0084] From Figures 7-10 It can be seen that the super-hydrophobic nanometer silicon dioxide obtained by using the preparation method provided by the application can freely roll on the surface without being absorbed, which shows that it has good hydrophobic effect.

[0085] From the above, it can be seen that the nanometer silicon dioxide is modified by using 3-mercaptopropyl triethoxysilane and F-MPTS, and the obtained super-hydrophobic nanometer silicon dioxide not only has good hydrophobic effect on water, but also has good hydrophobic effect on some water-soluble beverages and dyes.

[0086] The above only describes the preferred embodiments of the application, and it should be noted that the ordinary skilled in the art can make several improvements and refinements without departing from the principles of the application, and these improvements and refinements should also be regarded as the protection scope of the application.

Claims

1. A method for preparing superhydrophobic nanosilica, characterized in that, The method comprises the following steps: (1) mixing 3-mercaptopropyl triethoxysilane, methacrylic acid dodecafluoroheptyl ester, a first organic solvent and a first organic base to perform a click reaction to obtain F-MPTS; (2) mixing tetraethyl orthosilicate, a second organic solvent, deionized water and a second organic base to perform a hydrolysis reaction to obtain a nano-silica suspension; (3) adding 3-mercaptopropyl triethoxysilane and the F-MPTS obtained in the step (1) into the nano-silica suspension obtained in the step (2) to perform a hydrolysis condensation reaction to obtain super-hydrophobic nano-silica.

2. The production method according to claim 1, characterized by, The first organic solvent in the step (1) and the second organic solvent in the step (2) independently comprise ethanol and / or methanol.

3. The production method according to claim 1, characterized by, The first organic base in the step (1) and the second organic base in the step (2) independently comprise triethylamine and / or ammonia.

4. The method of claim 1, wherein, The mass ratio of 3-mercaptopropyl triethoxysilane to methacrylic acid dodecafluoroheptyl ester in the step (1) is 1:1-1:1.

5.

5. The preparation method according to claim 1, characterized in that, The temperature of the click reaction in the step (1) is room temperature, and the time of the click reaction is 3-12 hours.

6. The method of claim 1, wherein, In the step (2), the mass ratio of tetraethyl orthosilicate to deionized water is 1:10-1:1; the mass ratio of deionized water to the second organic base is 10:1-1:1; and the amount of the second organic solvent is 80%-99% of the total mass of the second organic solvent, deionized water and the second organic base.

7. The preparation method according to claim 1, characterized in that, The temperature of the hydrolysis reaction in the step (2) is 40-80°C, and the time of the hydrolysis reaction is 0.5-5 hours.

8. The method of claim 1, wherein, In the step (3), the mass ratio of 3-mercaptopropyl triethoxysilane to tetraethyl orthosilicate in the step (2) is 1:5-1:1; and the amount of F-MPTS is 15%-80% of the sum of the mass of 3-mercaptopropyl triethoxysilane and F-MPTS.

9. The method of claim 1, wherein, The temperature of the hydrolysis condensation reaction in the step (3) is 40-80°C, and the time of the hydrolysis condensation reaction is 1-6 hours.

10. Super-hydrophobic nano-silica prepared by the preparation method in any one of claims 1-9.

Images