A method for preparing hydrophobic and oleophobic polyorganosilsesquioxane spherical microparticles

Abstract

The application provides a preparation method of hydrophobic and oleophobic polyorganosilsesquioxane spherical microparticles. A binary catalytic system of a ruthenium complex with a tertiary phosphorus coordination group and an alkaline compound is used to hydrolyze polyorganosilsesquioxane molecular chains on the surface of polyorganosilsesquioxane spherical microparticles, to construct a rough micro-nano structure similar to chemical etching on the surface, and to convert part of the silicon-oxygen bonds on the surface into silicon hydroxyl groups. Then, a perfluoroalkylsilazane solution is added, and the perfluoroalkylsilazane reacts with the silicon hydroxyl groups, so that fluorine-containing alkylsiloxane is grafted to the surface of the polyorganosilsesquioxane particles to obtain modified polyorganosilsesquioxane spherical microparticles, which have superhydrophobicity and superoleophobicity, are insoluble in organic solvents, and have self-cleaning properties for hydrophilic and oleophilic pollutants.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of organic silicon materials, and particularly relates to a preparation method of hydrophobic and oleophobic polyorganosilsesquioxane spherical microparticles. BACKGROUND

[0002] Self-cleaning surfaces are one of the hotspots in the current material research. At present, self-cleaning coatings mainly include three types: super-hydrophilic self-cleaning coatings, super-hydrophobic self-cleaning coatings and photocatalytic active self-cleaning coatings. Among them, super-hydrophobic coatings have important applications in ship antifouling, radar signal anti-attenuation, high-voltage transmission anti-flash, fabric finishing and sports equipment due to their advantages of self-cleaning, water-repellent, small friction coefficient and strong weather resistance.

[0003] Super-hydrophobic coatings must have suitable micro-nano composite rough structures and low surface energy characteristics. Super-hydrophobic coatings can be prepared by first constructing a rough structure surface and then treating it with a low surface energy substance, or by constructing a rough structure on a low surface energy substance surface to achieve super-hydrophobicity. At present, super-hydrophobic self-cleaning coatings are usually prepared by etching, deposition, sol-gel and template methods.

[0004] Traditional etching and deposition methods usually have the disadvantages of requiring complex and expensive equipment, high-priced chemical reagents and harsh experimental conditions. Sol-gel methods generally require high-temperature calcination and chemical modification to have super-hydrophobic properties. Template methods are not suitable for large-scale preparation of super-hydrophobic coatings due to the limitation of the area of the template.

[0005] Therefore, it is important to develop a simple and efficient method for constructing micro-nano composite rough structures for realizing super-hydrophobic properties. Inorganic micro-nano particles are usually modified to be hydrophobic for constructing micro-nano composite rough structures, but the modified particles are only hydrophobic but not oleophobic and resistant to organic solvents, and cannot achieve long-term stable self-cleaning of oily and organic solvent pollutants. SUMMARY

[0006] In view of the above technical status, the application aims to provide a preparation method of hydrophobic and oleophobic polyorganosilsesquioxane spherical microparticles. The modified polyorganosilsesquioxane spherical microparticles prepared by the method have high hydrophobicity and high oleophobicity, and have self-cleaning properties for hydrophilic and oleophilic pollutants.

[0007] To achieve the above technical purposes, the technical solution adopted by the application is as follows: a preparation method of hydrophobic and oleophobic polyorganosilsesquioxane spherical microparticles, comprising the following steps:

[0008] (1) polyorganosilsesquioxane spherical microparticles, deionized water, and a catalyst are added to a container and heated and stirred to hydrolyze the polyorganosiloxane chains on the surface of the polyorganosilsesquioxane spherical microparticles and simultaneously convert some of the silicon-oxygen bonds on the surface of the polyorganosiloxane spherical microparticles to silicon-hydroxyl groups; the container is then cooled to room temperature; the catalyst is a binary catalytic system of a ruthenium complex with a tertiary phosphine ligand and a basic compound;

[0009] (2) a perfluoroalkylsilazane solution is added to the container and stirred at room temperature to react the perfluoroalkylsilazane with the silicon-hydroxyl groups on the surface of the polyorganosilsesquioxane particles to graft fluorine-containing alkylsiloxane onto the surface of the polyorganosilsesquioxane particles, and then nitrogen is introduced and the solvent is removed by heating.

[0010] The polyorganosilsesquioxane spherical microparticles can be unmodified polyorganosilsesquioxane spherical microparticles, such as polymethylsilsesquioxane spherical microparticles, or modified polyorganosilsesquioxane spherical microparticles, such as polyorganosilsesquioxane spherical microparticles containing vinyl groups, epoxy groups, methacryloxy groups, aminoalkyl groups, or phenyl groups.

[0011] Preferably, in step (1), the average particle size of the polyorganosilsesquioxane spherical microparticles is 0.1 to 30 μm.

[0012] Preferably, in step (1), the amount of deionized water is 0.1% to 5% by mass of the polyorganosilsesquioxane spherical microparticles, such as 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5%, or the like, and preferably 0.1% to 1%.

[0013] Preferably, in step (1), the amount of catalyst is 0.01% to 0.1% by mass of the polyorganosilsesquioxane spherical microparticles, such as 0.01%, 0.02%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, or the like, and preferably 0.01% to 0.05%.

[0014] Preferably, in step (1), the hydrolysis reaction temperature is 40 to 90°C, and further preferably 50 to 70°C.

[0015] Preferably, in step (1), the hydrolysis reaction time is 2 to 16 hours, and further preferably 8 to 12 hours.

[0016] Preferably, in step (1), the stirring speed is 120 to 600 rpm, and further preferably 240 to 480 rpm.

[0017] The catalyst is a mixed catalyst of a ruthenium complex with tertiary phosphine ligand and a basic compound. As a preference, the ruthenium complex contains a tertiary phosphine ligand, including but not limited to one or several of tricarbonylbis(triphenylphosphine) ruthenium, dichlorotris(triphenylphosphine) ruthenium, hydridochlorotris(triphenylphosphine) ruthenium, dihydrotetrakis(triphenylphosphine) ruthenium, ethylenetris(triphenylphosphine) ruthenium.

[0018] As a preference, the basic compound includes but is not limited to one or several of alkali metal hydroxide, aqueous ammonia, urea, pyridine, alkyl amine.

[0019] In the step (2), the perfluoroalkylsilazane solution is a solution of perfluoroalkylsilazane mixed with a solvent, where the solvent plays a dilution role and no chemical reaction occurs between the two. The solvent includes but is not limited to hexafluorobenzene.

[0020] As a preference, in the step (2), the mass percentage concentration of the perfluoroalkylsilazane solution is 1% to 5%.

[0021] As a preference, in the step (2), the number of carbon atoms of the perfluoroalkylsilazane is 3 to 15.

[0022] As a preference, in the step (2), the mass of the perfluoroalkylsilazane is 0.1% to 5% of the mass of the polyorganosilsesquioxane spherical microparticles, such as 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5%, and the like, and further preferably 0.5% to 3%.

[0023] As a preference, in the step (2), the reaction time is 12 h to 48 h, and further preferably 16 h to 30 h.

[0024] As a preference, in the step (2), the stirring speed is 120 rpm to 600 rpm, and further preferably 240 rpm to 480 rpm.

[0025] As a preference, in the step (2), when the solvent is hexafluorobenzene, the heating temperature is 60°C to 200°C, and further preferably 80°C to 120°C.

[0026] In the step (2), the perfluoroalkylsilazane reacts with the silicon hydroxyl group to generate small molecule ammonia, and in the process of purging nitrogen and removing the solvent by heating, the reaction byproduct ammonia is also removed as a preference.

[0027] In the step (2), if there is residual perfluoroalkylsilazane after the reaction, the following step (3) is further included as a preference:

[0028] (3) adding deionized water into the container and stirring under seal, the deionized water reacts with the residual perfluoroalkylsilazane to form fluorosiloxane and ammonia, and the surface modification of the polyorganosilsesquioxane is terminated; after the reaction is completed, cooling to room temperature.

[0029] As a preference, in the step (3), the reaction temperature is 30-90°C, and further preferably 50-70°C.

[0030] As a preference, in the step (3), the reaction time is 2h-18h, and further preferably 8h-14h.

[0031] As a preference, in the step (3), the stirring speed is 120-600rpm, and further preferably 240-480rpm.

[0032] As a preference, in the step (3), the mass of the deionized water added is 0.2%-2% of the mass of the polyorganosilsesquioxane.

[0033] In the step (3), if residual moisture remains after the reaction is completed, as a preference, the following step (4) is further included:

[0034] (4) adding methyl disilazane into the container and stirring under seal at room temperature, the methyl disilazane reacts with the unreacted water in the system to further remove the residual moisture in the reaction system; after the reaction is completed, nitrogen is introduced and the methyl disilazane is removed by heating.

[0035] As a preference, in the step (4), during the process of introducing nitrogen and removing the methyl disilazane by heating, the reaction byproduct ammonia is also removed.

[0036] As a preference, in the step (4), the heating temperature is 60-200°C.

[0037] As a preference, in the step (4), the reaction time is 12h-36h.

[0038] As a preference, in the step (4), the stirring speed is 240-480rpm.

[0039] As a preference, in the step (4), the methyl disilazane includes but is not limited to one or more of dimethyl disilazane, tetramethyl disilazane, and hexamethyl disilazane.

[0040] As a preference, in the step (4), the mass of the methyl disilazane is 0.2%-2% of the mass of the polyorganosilsesquioxane.

[0041] Compared with the prior art, the present application has the following beneficial effects:

[0042] (1) The surface of the polyorganosilsesquioxane spherical microparticles is smooth and has no reactivity, and the present application makes the surface polyorganosilsesquioxane molecular chain partially hydrolyze by using a specific catalyst to construct a rough micro-nano structure similar to chemical etching on the surface, significantly improving the roughness, and the process also converts part of the surface silicon-oxygen bonds into silicon hydroxyl groups, which react with perfluoroalkylsilazane to graft fluorine-containing alkyl siloxane onto the surface of the polyorganosilsesquioxane particles, achieving surface modification of the polyorganosilsesquioxane spherical microparticles.

[0043] (2) After surface modification, the surface of the polyorganosilsesquioxane spherical microparticles has hydrophobic, oil-transporting fluorine-containing groups, and the surface energy is low, which does not significantly interact with polar and nonpolar solvents or solutions such as water, alcohols, ketones, esters, and alkanes, and there is also no significant interaction between microparticles. Therefore, the modified polyorganosilsesquioxane spherical microparticles have superhydrophobic and superoleophobic properties, and the sheet material formed by hot pressing has a water contact angle and an oil contact angle both higher than 150°, i.e., the micro-nano rough structure surface has self-cleaning properties for hydrophilic and oleophilic contaminants, solving the problem that existing micro-nano rough structure superhydrophobic surfaces cannot achieve self-cleaning for oleophilic contaminants; at the same time, the modified polyorganosilsesquioxane spherical microparticles do not agglomerate in polar and nonpolar solvents or solutions such as water, alcohols, ketones, esters, and alkanes, can float on the liquid surface without sinking, have good dispersibility and compatibility, and can be widely used in the fields of resins and coatings. As a preferred embodiment, the temperature range in hot pressing is 250-350°C, and the pressure range is 5-35 MPa.

[0044] (3) After surface modification, the polyorganosilsesquioxane spherical microparticles have fluorine-containing siloxane components grafted on the surface, which can increase the high-temperature resistance and organic solvent resistance of the microparticles, and the introduction of fluorine also helps to improve the thermal stability of the microparticles, i.e., the heat resistance is increased. Therefore, the hydrophobic and oleophobic polyorganosilsesquioxane spherical microparticles of the present application also have excellent high-temperature resistance, lubricity, and organic solvent resistance, and at the same time, they do not melt at 900°C, can be converted into ceramic microparticles, and have high flame retardance and fire resistance, which can be applied to various extreme harsh application fields.

[0045] (4) The preparation process of the hydrophobic and oleophobic polyorganosilsesquioxane spherical microparticles of the present application is mild, simple, and easy to implement, and can realize large-scale and efficient preparation. BRIEF DESCRIPTION OF DRAWINGS

[0046] Figure 1 is a scanning electron microscope morphology diagram of the surface-modified polymethylsilsesquioxane spherical microparticles prepared in Example 1 of the present application.

[0047] Figure 2is a result chart when a tablet sample of the surface-modified polymethylsilsesquioxane spherical microparticles prepared in Example 1 of the present application is subjected to water and oil contact angle tests.

[0048] Figure 3 is a scanning electron microscope morphology chart of the surface-modified polymethylsilsesquioxane spherical microparticles prepared in Example 2 of the present application.

[0049] Figure 4 is a result chart when a tablet sample of the surface-modified polymethylsilsesquioxane spherical microparticles prepared in Example 3 of the present application is subjected to water and oil contact angle tests. DETAILED DESCRIPTION

[0050] The present application will be further described in detail below with reference to Examples, it being noted that the following Examples are intended to facilitate the understanding of the present application and do not limit the same in any way.

[0051] Example 1:

[0052] (1) 300 g of polymethylsilsesquioxane spherical microparticles having an average diameter of 0.27 μm, 1.5 g of deionized water, 0.110 g of tricarbonylbis(triphenyl) ruthenium and 0.093 g of pyridine were added to a planetary stirrer having a volume of 3 L, and stirred at a stirring speed of 400 rpm and a heating temperature of 60°C for 10 h in a closed state, and after the reaction was completed, cooled to room temperature.

[0053] (2) 100 g of a hexafluoroxylene solution of perfluorooctylsilazane was added to the planetary stirrer, the mass fraction of the perfluorooctylsilazane in the hexafluoroxylene solution was 3%, and after stirring for 24 h in a closed state at room temperature, nitrogen was introduced and heated to 120°C to remove hexafluoroxylene and the reaction by-product ammonia.

[0054] (3) 1.5 g of deionized water was added to the planetary stirrer, and stirred for 10 h in a closed state at 60°C, and then cooled to room temperature.

[0055] (4) 3 g of hexamethyldisilazane was added to the planetary stirrer, and stirred for 24 h in a closed state at room temperature, and then nitrogen was introduced and heated to 120°C to remove the hexamethyldisilazane and the reaction by-product ammonia, thereby obtaining a surface-modified polymethylsilsesquioxane spherical microparticle powder.

[0056] The morphology of the surface-modified polymethylsilsesquioxane spherical microparticles prepared above under a scanning electron microscope is shown in Figure 1

[0057] ​The surface-modified polymethylsilsesquioxane spherical microparticles prepared above do not agglomerate in polar and non-polar solvents or solutions such as water, alcohols, ketones, esters, and alkanes, and can float on the liquid surface without sinking. For example, the dispersibility of the polymethylsilsesquioxane spherical microparticles in step (1) above was 3-4 levels by dispersibility analysis using a carbon black dispersing instrument, while the dispersibility of the surface-modified polymethylsilsesquioxane spherical microparticles prepared in step (4) reached 10 levels in polyolefins, indicating that the surface-modified polymethylsilsesquioxane spherical microparticles have excellent dispersibility.

[0058] The surface-modified polymethylsilsesquioxane spherical microparticles prepared above were subjected to high-temperature hot pressing to prepare a sheet sample, and then subjected to water, oil contact angle and rolling angle tests, and the results are shown in Table 1. Figure 2 As shown in Table 1, the water contact angle of the sheet sample was 156.2°, the water rolling angle was 4.2°, the water hysteresis angle was 3.8°, the oil contact angle was 153.4°, the oil rolling angle was 4.9°, and the oil hysteresis angle was 4.1°, indicating that the surface-modified polymethylsilsesquioxane spherical microparticles have excellent superhydrophobic and superoleophobic properties.

[0059] Example 2:

[0060] (1) 200 g of polyphenylsilsesquioxane spherical microparticles with an average diameter of 0.25 μm, 1 g of deionized water, 0.084 g of hydrogen chloro tris (triphenyl phosphorus) ruthenium, and 0.037 g of potassium hydroxide were added to a planetary stirrer with a volume of 1 L, and stirred at a stirring speed of 200 rpm and a heating temperature of 70°C for 10 h in a closed state. After the reaction was completed, the temperature was cooled to room temperature.

[0061] (2) 70 g of a hexafluoroxylene solution of perfluorooctylsilazane was added to the planetary stirrer, and the mass fraction of perfluorooctylsilazane in the hexafluoroxylene solution was 2.6%. The mixture was stirred at room temperature in a closed state for 19 h, and then nitrogen was introduced and heated to 130°C to remove hexafluoroxylene and its reaction byproduct ammonia.

[0062] (3) 1 g of deionized water was added to the planetary stirrer, and stirred at 50°C in a closed state for 12 h, and then cooled to room temperature.

[0063] (4) 2 g of hexamethyldisilazane was added to the planetary stirrer, and stirred at room temperature in a closed state for 20 h, and then nitrogen was introduced and heated to 130°C to remove hexamethyldisilazane and its reaction byproduct ammonia, to obtain surface-modified polyphenylsilsesquioxane spherical microparticle powder.

[0064] The appearance of the surface-modified polymethylsilsesquioxane spherical microparticles prepared above under a scanning electron microscope is shown in FIG. 1. Figure 3

[0065] ​The surface-modified polyphenylsilsesquioxane spherical microparticles prepared above do not agglomerate in polar and non-polar solvents or solutions such as water, alcohols, ketones, esters, and alkanes, and can float on the surface of the liquid without sinking. For example, the dispersibility of the polymethylsilsesquioxane spherical microparticles in step (1) above was 3-4 levels, and the dispersibility of the surface-modified polymethylsilsesquioxane spherical microparticles prepared in step (4) in polyolefin reached 10 levels, indicating that the surface-modified polymethylsilsesquioxane spherical microparticles have excellent dispersibility.

[0066] The surface-modified polyphenylsilsesquioxane spherical microparticles prepared above were hot-pressed at high temperature to prepare a sheet sample, and then subjected to water, oil contact angle and rolling angle tests, and the results are shown in Table 1. Figure 4 As shown in Table 1, the water contact angle of the sheet sample was 155.3°, the water rolling angle was 4.1°, the water hysteresis angle was 3.9°, the oil contact angle was 153.8°, the oil rolling angle was 4.5°, and the oil hysteresis angle was 3.9°, showing excellent superhydrophobic and superoleophobic properties.

[0067] Example 3:

[0068] This example is basically the same as Example 1, except that in step (1), dichlorotris(triphenylphosphine) ruthenium is used instead of tricarbonylbis(triphenylphosphine) ruthenium, and alkylamine is used instead of pyridine, and the amount of deionized water added is 3 g.

[0069] The surface-modified polymethylsilsesquioxane spherical microparticles prepared in this example do not agglomerate in polar and non-polar solvents or solutions such as water, alcohols, ketones, esters, and alkanes, and can float on the surface of the liquid without sinking. The surface-modified polymethylsilsesquioxane spherical microparticles prepared were hot-pressed at high temperature to prepare a sheet sample, and then subjected to water, oil contact angle and rolling angle tests, and the contact angles with water and oil were both higher than 150°.

[0070] Example 4:

[0071] This example is basically the same as Example 2, except that in step (1), dihydrogen tetrakis(triphenylphosphine) ruthenium is used instead of dichlorotris(triphenylphosphine) ruthenium, and ammonia is used instead of potassium hydroxide.

[0072] The surface-modified polymethylsilsesquioxane spherical microparticles prepared in this example do not agglomerate in polar and non-polar solvents or solutions such as water, alcohols, ketones, esters, and alkanes, and can float on the surface of the liquid without sinking. The surface-modified polymethylsilsesquioxane spherical microparticles prepared were hot-pressed at high temperature to prepare a sheet sample, and then subjected to water, oil contact angle and rolling angle tests, and the contact angles with water and oil were both higher than 150°.

[0073] Example 5:

[0074] The present example is basically the same as example 1, except that in step (1), ethylene tris(triphenylphosphine) ruthenium is used instead of tricarbonylbis(triphenylphosphine) ruthenium, and urea is used instead of pyridine.

[0075] The surface-modified polymethylsilsesquioxane spherical microparticles prepared in the present embodiment do not agglomerate in polar and non-polar solvents or solutions such as water, alcohols, ketones, esters, and alkanes, and can float on the surface of the liquid without sinking. The surface-modified polymethylsilsesquioxane spherical microparticles prepared are subjected to high-temperature hot pressing to produce a sheet-shaped sample, which is then subjected to water and oil contact angle and rolling angle tests. The water and oil contact angles are both higher than 150°.

[0076] The above-described embodiments are used to describe the technical solutions of the present application in detail, and it should be understood that the above-described only are specific embodiments of the present application, and are not used to limit the present application. Any modification, supplement, or similar replacement within the principle range of the present application should be included in the protection scope of the present application.

Claims

1. A process for the preparation of hydrophobic and oleophobic polyorganosilsesquioxane spherical microparticles, characterized by: The method comprises the following steps: (1) adding polyorganosilsesquioxane spherical microparticles, deionized water and a catalyst into a container for closed heating and stirring, so that the polyorganosilsesquioxane molecular chains on the surface of the polyorganosilsesquioxane spherical microparticles are hydrolyzed, and at the same time, part of the silicon-oxygen bonds on the surface of the polyorganosilsesquioxane spherical microparticles are converted into silicon hydroxyl groups; and then cooling to room temperature; the catalyst is a binary catalytic system of a tertiary phosphorus ligand ruthenium complex and an alkaline compound; (2) adding a perfluoroalkylsilazane solution into the container, and stirring at room temperature in a closed state, so that the perfluoroalkylsilazane reacts with the silicon hydroxyl groups to graft fluorine-containing alkyl siloxane onto the surface of the polyorganosilsesquioxane particles, and then nitrogen is introduced and heated to remove hexafluorobenzene; The contact angle of the prepared polyorganosilsesquioxane spherical microparticles to water is higher than 150°, and the contact angle to oil is higher than 150°.

2. The production method according to claim 1, characterized by: The polyorganosilsesquioxane spherical microparticles are unmodified polyorganosilsesquioxane spherical microparticles or modified polyorganosilsesquioxane spherical microparticles.

3. The production method according to claim 2, characterized by: The unmodified polyorganosilsesquioxane spherical microparticles include polymethylsilsesquioxane spherical microparticles.

4. The method of claim 2, wherein the method further comprises: The modified polyorganosilsesquioxane spherical microparticles include polyorganosilsesquioxane spherical microparticles containing one or more of vinyl groups, epoxy groups, methacryloyloxy groups, aminoalkyl groups and phenyl groups.

5. The method of claim 1 wherein: The tertiary phosphorus ligand ruthenium complex includes one or more of tricarbonylbis(triphenylphosphine)ruthenium, dichlorotris(triphenylphosphine)ruthenium, hydrochlorotris(triphenylphosphine)ruthenium, dihydrogen tetra(triphenylphosphine)ruthenium and vinyltris(triphenylphosphine)ruthenium.

6. The method of claim 1 wherein: The alkaline compound includes one or more of alkali metal hydroxides, aqueous ammonia, urea, pyridine and alkyl amines.

7. The production method according to claim 1, wherein: In the step (1), the mass of the deionized water is 0.1% to 5% of the mass of the polyorganosilsesquioxane spherical microparticles.

8. The method of claim 7, wherein the method further comprises: In the step (1), the mass of the deionized water is 0.1% to 1% of the mass of the polyorganosilsesquioxane spherical microparticles.

9. The method of claim 1 wherein: In the step (1), the mass of the catalyst is 0.01% to 0.1% of the mass of the polyorganosilsesquioxane spherical microparticles.

10. The method of claim 9, wherein the method further comprises: In the step (1), the mass of the catalyst is 0.01% to 0.05% of the mass of the polyorganosilsesquioxane spherical microparticles.

11. The method of claim 1 wherein: In the step (1), the hydrolysis reaction temperature is 40 to 90°C.

12. The preparation method according to claim 1, characterized in that: In the step (1), the hydrolysis reaction temperature is 50 to 70°C.

13. The preparation method according to claim 1, characterized in that: In the step (1), the hydrolysis reaction time is 2 to 16 hours.

14. The preparation method according to claim 1, characterized in that: In the step (1), the hydrolysis reaction time is 8 to 12 hours.

15. The preparation method according to claim 1, characterized in that: In the step (1), the stirring speed is 120 to 600 rpm.

16. The preparation method according to claim 1, characterized in that: In the step (1), the stirring speed is 240 to 480 rpm.

17. The preparation method according to claim 1, characterized in that: In the step (1), the average particle size of the polyorganosilsesquioxane spherical microparticles is 0.1 to 30 μm.

18. The preparation method according to claim 1, characterized in that: In the step (2), the mass percentage concentration of the perfluoroalkylsilazane solution is 1% to 5%.

19. The preparation method according to claim 1, characterized in that: In the step (2), the solvent in the perfluoroalkylsilazane solution is hexafluorobenzene.

20. The method of claim 1 wherein: In the step (2), the number of carbon atoms in the perfluoroalkylsilazane is 3 to 15.

21. The method of claim 1 wherein: In step (2), the mass of the perfluorocarbon-based silazane is 0.1% to 5% of the mass of the polyorganosilicon spherical particles.

22. The method of claim 21, wherein: In step (2), the mass of the perfluorocarbon silazane is 0.5% to 3% of the mass of the polyorganosilicon spherical particles.

23. The preparation method according to claim 1, characterized in that: In step (2), the reaction time is 12h~48h.

24. The method of claim 23, wherein: In step (2), the reaction time is 16h~30h.

25. The preparation method according to claim 1, characterized in that: In step (2), the stirring speed is 120~600 rpm.

26. The method of claim 25, wherein: In step (2), the stirring speed is 240~480 rpm.

27. The preparation method according to claim 1, characterized in that: In step (2), when the solvent is hexafluoroxylene, the heating temperature is 60~200℃.

28. The preparation method according to claim 27, characterized in that: The heating temperature is 80~120℃.

29. The preparation method according to claim 1, characterized in that: If there is residual perfluoroalkylsilazane after the reaction in step (2), the following step (3) is also included: (3) Add deionized water to the container and stir in a closed container. The deionized water reacts with the remaining perfluoroalkyl silazane to form fluorosiloxane and ammonia, thereby terminating the surface modification of polyorganosilicon silsesquioxane. After the reaction is completed, cool to room temperature.

30. The method of claim 29, wherein: In step (3), the reaction temperature is 30~90℃.

31. The method of claim 29, wherein: In step (3), the reaction temperature is 50~70℃.

32. The method of claim 29, wherein: In step (3), the reaction time is 2h to 18h.

33. The method of claim 32, wherein: In step (3), the reaction time is 8h~14h.

34. The method of claim 29, wherein: In step (3), the stirring speed is 120~600 rpm.

35. The preparation method according to claim 34, characterized in that: In step (3), the stirring speed is 240~480 rpm.

36. The method of claim 29, wherein: The mass of deionized water added in step (3) is 0.2% to 2% of the mass of polyorganosilicon sesquioxane.

37. The preparation method according to claim 1, characterized in that: If residual water remains after the reaction in step (3), the following step (4) is also included: (4) Add methyldisilazane to a container and stir in a closed container at room temperature. Methyldisilazane reacts with unreacted water in the system to remove residual water in the reaction system. After the reaction is complete, nitrogen gas is introduced and heated to remove methyldisilazane.

38. The method of claim 37, wherein the method is prepared by: In step (4), the heating temperature is 60~200℃.

39. The preparation method according to claim 37, characterized in that: In step (4), the reaction time is 12~36h.

40. The preparation method according to claim 37, characterized in that: In step (4), the stirring speed is 240~480 rpm.

41. The preparation method according to claim 37, characterized in that: In step (4), methyldisilazane includes one or more of dimethyldisilazane, tetramethyldisilazane, and hexamethyldisilazane.

42. The method of claim 37, wherein the method is carried out at a temperature of from about 20°C to about 30°C. In step (4), during the process of introducing nitrogen gas and heating to remove methyldisilazane, the reaction byproduct ammonia is also removed.

43. The preparation method according to claim 37, characterized in that: In step (4), the mass of methyldisilazane is 0.2% to 2% of the mass of polyorganosilicon sesquioxane.

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