Hollow silicon dioxide microsphere with low dielectric constant and dielectric loss and preparation method thereof

Abstract

The invention relates to the technical field of preparation of silicon dioxide microspheres, in particular to hollow silicon dioxide microspheres with low dielectric constant and dielectric loss and a preparation method of the hollow silicon dioxide microspheres. The hollow silicon dioxide microspheres are prepared by taking a silicon-based amphiphilic random copolymer as a surfactant to coat an oil phase so as to obtain an emulsion and then curing the emulsion, the average particle size of the hollow silicon dioxide microspheres is 0.2-10.0 [mu] m, and the span is less than 2.0; the porosity of the hollow silicon dioxide microspheres is 30-90%; the dielectric constant of the hollow silicon dioxide microspheres is less than 2.3, and the dielectric loss is less than 0.0005. A silicon-based amphiphilic random copolymer precursor is used as a surfactant to encapsulate an oil phase to prepare a micron emulsion, then in the alkali catalysis curing treatment process, alkoxy silane is subjected to a hydrolytic condensation reaction on an oil-water two-phase interface to form a silicon dioxide shell, and finally, the micron hollow silicon dioxide microspheres are obtained through washing and drying. The preparation method is simple in process and good in reproducibility.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of silica microsphere preparation, and particularly relates to a hollow silica microsphere with low dielectric constant and dielectric loss and a preparation method thereof. BACKGROUND

[0002] In recent years, in order to meet the needs of high-performance computers, new-generation mobile communications, artificial intelligence, automobile electronics and national defense equipment, electronic products are developing towards high performance and high integration. High performance requires that the packaging and substrate materials used in electronic products have low dielectric constant (Dk) and low dielectric loss (Df), and high integration requires that the materials, such as the fillers of insulating materials, have a small particle size. Hollow silica microspheres have the advantages of silica materials and air ultra-low dielectric constant, and have attracted a lot of attention as low-dielectric fillers.

[0003] At present, researchers have developed various strategies to synthesize hollow silica spheres, mainly including copolymer micelle / emulsion template method, copolymer hard sphere template method, inorganic template method and solid silica dissolution method. Patent CN115304071A discloses a manufacturing method of silica hollow particles, which first forms a core-sheath particle by coating a sheath-forming material on a core particle; then removes the core particle from the core-sheath particle to obtain a sheath of a hollow silica particle precursor; and finally obtains a hollow silica particle that helps to improve dielectric properties by firing the sheath. The composite material prepared by mixing the hollow silica microspheres prepared by the method with bisphenol F type epoxy resin can achieve a low dielectric constant (2.44) and a low dielectric loss (0.0004). However, the method uses alunite-type compounds as core particles, and needs to be subjected to multiple long-time acid washing after firing to remove the core material, and the molar ratio of Al / Si in the final product is still 0.018.

[0004] Patent CN116529321A discloses a manufacturing method of silica hollow particles, mainly including the following steps: a hollow particle preparation step of preparing hollow particles by spray drying a silicate alkali aqueous solution in a hot air stream; an alkali removal step of neutralizing and removing the alkali contained in the prepared hollow particles with an acid; a firing step of firing the hollow particles from which the alkali is removed; and a classification step of removing coarse particles by classifying the hollow particles between the hollow particle preparation step and the firing step. The method realizes the preparation of hollow silica microspheres with an average particle size (D50) of 0.1-10 μm, and achieves a low dielectric constant (2.2) and a low dielectric loss (0.0004). However, the hot air stream spray drying technology in the method is difficult to accurately control the size, hollow structure and morphology of the hollow particles, and has high requirements on the equipment; the subsequent classification process is complicated and also difficult to control the particles. SUMMARY

[0005] The application provides a hollow silica microsphere with low dielectric constant and dielectric loss and a preparation method thereof, and aims to solve the problems of complex preparation process and poor reproducibility in the preparation technology of the existing low-dielectric hollow silica microsphere filler.

[0006] In order to achieve the above-mentioned purpose, the application adopts the following technical solutions.

[0007] In a first aspect, the application provides a hollow silica microsphere with low dielectric constant and dielectric loss, which is prepared by using a silicon-based amphiphilic random copolymer as a surfactant to encapsulate an oil phase to obtain an emulsion, and then solidifying the emulsion.

[0008] The average particle size of the hollow silica microsphere is 0.2-10.0 μm, and the span is <2.0.

[0009] The porosity of the hollow silica microsphere is 30-90%.

[0010] The dielectric constant of the hollow silica microsphere is <2.3, and the dielectric loss is <0.0005.

[0011] In a second aspect, the application provides a preparation method of the hollow silica microsphere, and the method comprises the following steps.

[0012] S1. Hydrolysis and condensation of a tetraalkoxysilane, a hydrophobic silane compound and a hydrophilic silane compound in an organic solvent are carried out by using an inorganic acid as a catalyst, and then the solvent is removed to obtain a silicon-based amphiphilic random copolymer.

[0013] S2. The silicon-based amphiphilic random copolymer is used to encapsulate an oil phase to prepare a microemulsion.

[0014] S3. The microemulsion is subjected to a solidification reaction by using an alkali as a catalyst, and then the solid phase is collected, washed and dried to obtain a hollow silica microsphere.

[0015] Preferably, the alkoxyl group in the tetraalkoxysilane includes at least one of a methoxyl group, an ethoxyl group or an isopropoxyl group.

[0016] The hydrophobic silane compound includes at least one of an alkyl silane, a vinyl silane, a phenyl silane or an acryloyloxy silane.

[0017] The hydrophilic silane compound includes at least one of an amino silane, a sulfonic acid silane, an epoxy silane, a diethylene glycol monomethyl ether silane, a triethylene glycol monomethyl ether silane or a polyethylene glycol monomethyl ether silane.

[0018] The organic solvent includes at least one of methanol, ethanol, isopropyl alcohol or butanol.

[0019] Further preferably, the tetraalkoxysilane comprises tetraethyl orthosilicate;

[0020] The hydrophobic silane compound comprises at least one of phenyltriethoxysilane, n-propyltriethoxysilane, n-octyltriethoxysilane or methacryloyloxypropyltriethoxysilane;

[0021] The hydrophilic silane compound comprises at least one of γ-glycidoxypropyltriethoxysilane, polyethylene glycol 500 monomethyl ether triethoxysilane propyl ether or 3-aminopropyltriethoxysilane.

[0022] Preferably, the mass ratio of the hydrophobic silane compound to the tetraalkoxysilane is 0-0.5:1;

[0023] The mass ratio of the hydrophilic silane compound to the tetraalkoxysilane is 0.2-0.6:1.

[0024] Preferably, the inorganic acid comprises any one of hydrochloric acid, nitric acid or sulfuric acid;

[0025] The mass ratio of the inorganic acid to the tetraalkoxysilane is 0.05-0.2:1.

[0026] Preferably, the reaction temperature of the hydrolytic condensation in S1 is 60-160℃, and the reaction time is 4-12h;

[0027] The solvent is removed by normal pressure high temperature distillation, reduced pressure distillation or thin film evaporation.

[0028] Preferably, in S2, the micron emulsion is prepared by stirring and mixing the silicon-based amphiphilic random copolymer, the oil phase and water, so that the silicon-based amphiphilic random copolymer encapsulates the oil phase;

[0029] The mass ratio of the silicon-based amphiphilic random copolymer, the oil phase and water is 1:(1-4):(4-20);

[0030] The oil phase is any one of n-heptane, n-hexane, cyclohexane, ethyl acetate, n-butyl acetate or toluene.

[0031] Preferably, in S3, the micron emulsion is subjected to a curing reaction under the catalysis of a base, specifically:

[0032] The base catalyst is added to the micron emulsion, the pH is adjusted to 10-11, and then the mixture is stirred uniformly; then the temperature is raised to 80-90℃ for the curing reaction;

[0033] The base catalyst comprises aqueous ammonia, aqueous sodium hydroxide or aqueous potassium hydroxide.

[0034] Preferably, in S3, deionized water is used for washing.

[0035] The drying comprises: heating the solid phase to 80-90 DEG C, heating for 4-5h; heating to 130-140 DEG C again, heating for 3-4h.

[0036] Compared with the prior art, the application has the following beneficial effects:

[0037] The application prepares a microemulsion by using a silicon-based amphiphilic random copolymer precursor as a surfactant to encapsulate an oil phase, then in an alkaline catalytic curing process, hydrolysis and condensation of the alkoxysilane occurs on the interface of the oil-water two phases to form a silica shell, and finally the micro hollow silica microspheres are obtained through washing and drying.

[0038] The emulsion prepared by using the silicon-based amphiphilic random copolymer has stable thermodynamic properties, can make the silane compound grow through interface diffusion to form a complete silica shell, and makes the micro hollow silica microspheres have the advantages of good uniformity, controllable particle size, high porosity, etc. The average particle size (D50) of the prepared hollow silica microspheres is 0.2-10.0 μm, the particle size span of the microspheres is less than 2.0, the porosity of the microspheres is 30-90%, the dielectric constant is less than 2.3, and the dielectric loss is less than 0.0005. BRIEF DESCRIPTION OF DRAWINGS

[0039] In order to more clearly illustrate the technical solutions of the embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description are only some embodiments described in the application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0040] Figure 1 It is a scanning electron microscope graph of the hollow silica microspheres of Example 1;

[0041] Figure 2 It is a transmission electron microscope graph of the hollow silica microspheres of Example 1;

[0042] Figure 3 It is a scanning electron microscope graph of the hollow silica microspheres of Example 2;

[0043] Figure 4 It is a scanning electron microscope graph of the hollow silica microspheres of Example 3;

[0044] Figure 5 It is a scanning electron microscope graph of the hollow silica microspheres of Example 4. DETAILED DESCRIPTION

[0045] With reference to the drawings and the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described. Obviously, the described embodiments are some of the embodiments of the present application, but not all the embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of the present application.

[0046] In the following description of the embodiments of the present application, the terms "comprising", "containing", "having" and "including" and the like are open-ended terms, i.e., meaning "including, but not limited to".

[0047] In the following description of the embodiments of the present application, the term "and / or" is used to describe the association relationship of the associated objects, which means that there can be three kinds of relationships, for example, A and / or B, which can represent the cases of A alone, B alone and A and B existing at the same time. Wherein A and B can be singular or plural. The character " / " generally represents an "or" relationship between the front and rear associated objects.

[0048] In the following description of the embodiments of the present application, the term "at least one" means one or more, and "multiple" means two or more. "At least one of the following (one)" or the like means any combination of these items, including any combination of single (one) or multiple items. For example, "at least one of a, b or c", or "at least one of a, b and c", can represent a, b, c, a-b (i.e., a and b), a-c, b-c, or a-b-c, wherein a, b, and c can be single or multiple.

[0049] The terms used in the embodiments of the present application are merely for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "a" and "the" used in the embodiments of the present application and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise.

[0050] Those skilled in the art should understand that in the following description of the embodiments of the present application, the order of the serial numbers does not mean the order of execution, and some or all steps can be executed in parallel or in sequence, and the execution order of each process should be determined according to its function and inherent logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0051] Those skilled in the art should understand that the numerical ranges in the embodiments of the present application should be understood as each intermediate value between the upper limit and the lower limit of the range. Each smaller range between any stated value or stated range and any other stated value or intermediate value within the stated range is also included in the present application. The upper limit and the lower limit of these smaller ranges can be independently included or excluded from the range.

[0052] Unless otherwise indicated, the technical / scientific terms used herein have the same meaning as is commonly understood by one of ordinary skill in the art to which this application belongs. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present application, preferred methods and materials are described. All documents mentioned herein are incorporated by reference to disclose and describe the methods and / or materials in connection with which the documents are cited. In case of conflict between the content of the specification and that of any document incorporated herein by reference, the content of the specification prevails.

[0053] In a first aspect, the present application provides a hollow silica microsphere with low dielectric constant and dielectric loss, which is prepared by encapsulating an oil phase with a silicon-based amphiphilic random copolymer as a surfactant to obtain an emulsion, and then solidifying the emulsion. The average particle size of the hollow silica microsphere of the present application is 0.2-10.0 μm, and the span is <2.0; the porosity of the hollow silica microsphere is 30-90%; the dielectric constant of the hollow silica microsphere is <2.3, and the dielectric loss is <0.0005.

[0054] The hollow silica microsphere of the present application can be used in lightweight composites, electrical insulation materials, thermal insulation, sound insulation, and high-frequency high-speed communication scenarios.

[0055] The present application provides a method for preparing a hollow silica microsphere with low dielectric constant and dielectric loss, comprising:

[0056] S1, tetraalkoxysilane, hydrophobic silane compound and hydrophilic silane compound are hydrolyzed and condensed in an organic solvent by inorganic acid catalysis, and after removing the solvent, a silicon-based amphiphilic random copolymer is obtained;

[0057] In the present application, the alkoxyl group of the tetraalkoxysilane includes at least one of methoxy, ethoxy or isopropoxy; the tetraalkoxysilane is preferably tetraethyl orthosilicate.

[0058] The hydrophobic silane compound contains a hydrophobic group; the hydrophobic silane compound includes at least one of alkylsilane, vinylsilane, phenylsilane or acryloyloxy silane, such as any one or a mixture of two or more of phenyltriethoxysilane, n-propyltriethoxysilane, n-octyltriethoxysilane or methacryloyloxypropyltriethoxysilane.

[0059] The hydrophilic silane compound contains a hydrophilic group; the hydrophilic silane compound includes at least one of aminosilane, sulfonic silane, epoxy silane, diethylene glycol monomethyl ether silane, triethylene glycol monomethyl ether silane or polyethylene glycol monomethyl ether silane. Among them, the polyethylene glycol methyl ether silane preferably has a molecular weight of 350-2000, such as a molecular weight of 350, 500, 800, 1000 or 2000.

[0060] Specifically, the hydrophilic silane compound can be any one of gamma-glycidoxypropyl triethoxysilane, polyethylene glycol 500 monomethyl ether triethoxysilane propyl ether or 3-aminopropyl triethoxysilane, or a mixture of two or more thereof.

[0061] The organic solvent includes at least one of methanol, ethanol, isopropanol and butanol.

[0062] In the present application, the mass ratio of the hydrophobic silane compound to the tetraalkoxysilane is preferably 0-0.5:1, and the mass ratio of the hydrophilic silane compound to the tetraalkoxysilane is 0.2-0.6:1.

[0063] In the present application, the inorganic acid includes any one of hydrochloric acid, nitric acid or sulfuric acid, and the mass ratio of the inorganic acid to the tetraalkoxysilane is preferably 0.05-0.2:1. The reaction temperature of the hydrolysis condensation is 60-160℃, and the reaction time is 4-12h.

[0064] After the hydrolysis condensation reaction, the solvent is preferably removed by normal pressure high temperature distillation, reduced pressure distillation or thin film evaporation to obtain the silicon-based amphiphilic random copolymer.

[0065] S2, the silicon-based amphiphilic random copolymer is loaded with an oil phase to prepare a microemulsion;

[0066] Specifically, the silicon-based amphiphilic random copolymer and the oil phase are added to deionized water, and stirred at a speed of 500-10000r / min at 15-30℃ for 5-45min to obtain a white emulsion. The mass ratio of the silicon-based amphiphilic random copolymer, the oil phase and water is preferably 1:(1-4):(4-20).

[0067] In the present application, the oil phase is preferably any one of n-heptane, n-hexane, cyclohexane, ethyl acetate, n-butyl acetate or toluene, and more preferably cyclohexane.

[0068] S3, the microemulsion is subjected to a curing reaction under the catalysis of a base, and the solid phase is collected, washed and dried to obtain the hollow silica microspheres.

[0069] In the present application, the microemulsion is subjected to a curing reaction under the catalysis of a base, specifically:

[0070] The base catalyst is added to the microemulsion, the pH is adjusted to 10-11, and then stirred uniformly. Then, the temperature is increased to 80-90℃ for the curing reaction.

[0071] The base catalyst includes aqueous ammonia, aqueous sodium hydroxide or aqueous potassium hydroxide.

[0072] In the present application, the product after the curing reaction is separated by sedimentation, the solid phase is collected, and deionized water is used for washing; then drying. The drying is specifically heating the solid phase to 80-90℃ for 4-5h; then heating to 130-140℃ for 3-4h.

[0073] In the present application, the microemulsion is prepared by using the silicon-based amphiphilic random copolymer precursor as a surfactant to encapsulate the oil phase, then in the process of alkaline catalytic curing treatment, the hydrolysis and condensation reaction of alkoxysilane occurs on the interface of oil-water to form a silica shell, and finally the micro hollow silica microspheres are obtained after washing and drying. The preparation method has simple process, good reproducibility, low requirement for equipment, and is suitable for large-scale production.

[0074] The emulsion prepared by using the silicon-based amphiphilic random copolymer in the present application has stable thermodynamic properties, can make the silane compound diffuse and grow through the interface to form a complete silica shell, and the micro hollow silica microspheres have the advantages of good uniformity, controllable particle size, high porosity and the like.

[0075] The present application is further illustrated by the following examples.

[0076] Example 1

[0077] The present embodiment provides a preparation method of hollow silica microspheres with low dielectric constant and dielectric loss, comprising:

[0078] S1, 208g of tetraethyl orthosilicate, 50g of γ-glycidoxypropyl triethoxysilane, 20g of phenyl triethoxysilane and 50g of ethanol are uniformly mixed, after stirring for 5min, 10g of hydrochloric acid (mass fraction of 37%) and 5g of deionized water are added respectively and uniformly mixed, heated to 80℃ and reacted for 12h, after the reaction is completed, the solvent and low molecular weight compounds in the system are quickly removed by distillation under reduced pressure, to obtain a silicon-based amphiphilic random copolymer with certain viscosity and flowability;

[0079] S2, 30g of the silicon-based amphiphilic random copolymer and 50g of cyclohexane are mixed and then added into 300mL of deionized water, stirred at a speed of 8000rpm at 20℃ for 30min to obtain a precursor emulsion;

[0080] S3, 15mL of ammonia water with a concentration of 28wt% is added to the precursor emulsion, stirred at a speed of 8000rpm for 30min, then stirred at room temperature for 2h, and then heated to 80℃ and stirred for 24h to obtain a white emulsion; after the white emulsion is settled at room temperature, the supernatant is poured off, and the precipitate is collected; the precipitate is washed with deionized water and then settled again, and the precipitate is collected. The precipitate is dried at 80℃ for 5h, and then heated to 130℃ for 3h to obtain a dry white powder, i.e. hollow silica microspheres.

[0081] Example 2

[0082] The present example provides a method for preparing hollow silica microspheres with low dielectric constant and dielectric loss, comprising:

[0083] S1, the same as example 1;

[0084] S2, 50g of silicon-based amphiphilic random copolymer and 100g of cyclohexane were mixed and then added to 300mL of deionized water, stirred at 6000rpm for 30min at 20℃, to obtain a precursor emulsion;

[0085] S3, 15mL of ammonia water with a concentration of 28wt% was added to the precursor emulsion, stirred at 6000rpm for 10min, then stirred at room temperature for 2h, and then heated to 80℃ and stirred for 24h, to obtain a white emulsion; the white emulsion was settled at room temperature, and the supernatant was poured off, and the precipitate was collected; the precipitate was washed with deionized water and then settled again, and the precipitate was collected. The precipitate was dried at 80℃ for 5h, and then heated to 130℃ and dried for 3h, to obtain a dry white powder, i.e. hollow silica microspheres.

[0086] Example 3

[0087] The present example provides a method for preparing hollow silica microspheres with low dielectric constant and dielectric loss, comprising:

[0088] S1, 208g of tetraethyl orthosilicate, 50g of polyethylene glycol 500 monomethyl ether triethoxysilyl propyl ether, 20g of phenyltriethoxysilane and 50g of ethanol were mixed uniformly, and after stirring for 5min, 10g of hydrochloric acid (mass fraction of 37%) and 5g of deionized water were added respectively and mixed uniformly, heated to 80℃ and reacted for 16h, after the reaction was completed, the solvent and low molecular weight compounds in the system were quickly removed by distillation under reduced pressure, to obtain a silicon-based amphiphilic random copolymer with certain viscosity and flowability;

[0089] S2, the same as example 1;

[0090] S3, the same as example 1.

[0091] Example 4

[0092] The present example provides a method for preparing hollow silica microspheres with low dielectric constant and dielectric loss, comprising:

[0093] S1, the same as example 1;

[0094] S2, 30g of silicon-based amphiphilic random copolymer and 50g of n-butyl acetate were mixed and then added to 300mL of deionized water, stirred at 8000rpm for 30min at 20℃, to obtain a precursor emulsion;

[0095] S3, same as example 1.

[0096] The hollow silica microspheres prepared in examples 1-4 were tested by scanning electron microscopy and transmission electron microscopy for morphology analysis. The results are shown in Figures 1-5 Figure 1 is a scanning electron micrograph of the hollow silica microspheres of example 1, Figure 2 is a transmission electron micrograph of the hollow silica microspheres of example 1; Figures 3-5 are scanning electron micrographs of the hollow silica microspheres of examples 2-4, respectively.

[0097] The hollow silica microspheres prepared in examples 1-4 were tested as follows:

[0098] The particle size of the hollow silica microspheres was tested by a laser particle size analyzer. The porosity was calculated from the wall thickness data obtained by transmission electron microscopy and scanning electron microscopy in combination with the particle size data.

[0099] The dielectric constant and dielectric loss of the hollow silica dry powder at 10 GHz were tested by a split post dielectric resonator (SPDR) method. The results are shown in Table 1 below.

[0100] Table 1 Test results of hollow silica microspheres

[0101]

[0102] From Table 1 and Figures 1-5 It can be seen that the hollow silica microspheres of examples 1-4 are obtained, the microspheres have high sphericity, the surface is basically free of wrinkles and broken holes, the size is controllable and the particle size distribution is uniform, and the porosity is 40-80%.

[0103] The hollow silica microspheres prepared in examples 1-4 all have low dielectric constant and low dielectric loss, the dielectric constant is less than 2.3, the lowest is 2.104, and the dielectric loss is only 0.0003-0.0004.

[0104] Although the present application has been described in detail in the foregoing description with specific reference to certain embodiments, it will be understood by those skilled in the art that various modifications or changes can be made to the application without departing from the spirit and scope thereof. Accordingly, modifications and improvements to the application made by others in light of the above detailed description shall not be regarded as a departure from the scope and spirit of the application.​

Claims

1. Hollow silica microspheres having low dielectric constant and dielectric loss, characterized in that, The emulsion is prepared by encapsulating an oil phase with a silicon-based amphiphilic random copolymer as a surfactant, and the hollow silica microspheres are prepared by solidifying the emulsion; The average particle size of the hollow silica microspheres is 0.2-10.0 μm, and the diameter distance is <2.0; The porosity of the hollow silica microspheres is 30-90%; The dielectric constant of the hollow silica microspheres is <2.3, and the dielectric loss is <0.0005.

2. The method of claim 1, wherein the hollow silica microspheres are prepared by the steps of: Comprise: S1, tetraalkoxysilane, hydrophobic silane compound and hydrophilic silane compound are hydrolyzed and condensed in an organic solvent by inorganic acid catalysis, and after removing the solvent, a silicon-based amphiphilic random copolymer is obtained; S2, the silicon-based amphiphilic random copolymer encapsulates the oil phase to prepare a microemulsion; S3, the microemulsion is subjected to a solidification reaction by alkali catalysis, and the solid phase is collected, washed and dried to obtain hollow silica microspheres.

3. The preparation method according to claim 2, characterized in that, The tetraalkoxysilane includes at least one of methoxy, ethoxy or isopropoxy; The hydrophobic silane compound includes at least one of alkylsilane, vinylsilane, phenylsilane or acryloyloxy silane; The hydrophilic silane compound includes at least one of aminosilane, sulfonic silane, epoxy silane, diethylene glycol monomethyl ether silane, triethylene glycol monomethyl ether silane or polyethylene glycol monomethyl ether silane; The organic solvent includes at least one of methanol, ethanol, isopropanol or butanol.

4. The production method according to claim 3, characterized by, The tetraalkoxysilane includes tetraethyl orthosilicate; The hydrophobic silane compound includes at least one of phenyltriethoxysilane, n-propyltriethoxysilane, n-octyltriethoxysilane or methacryloyloxypropyltriethoxysilane; The hydrophilic silane compound includes at least one of gamma-glycidyl ether oxygen propyl triethoxysilane, polyethylene glycol 500 monomethyl ether triethoxysilane propyl ether or 3-aminopropyl triethoxysilane.

5. The preparation method according to claim 2, characterized in that, The mass ratio of the hydrophobic silane compound to the tetraalkoxysilane is 0-0.5:1; The mass ratio of the hydrophilic silane compound to the tetraalkoxysilane is 0.2-0.6:

1.

6. The preparation method according to claim 2, characterized in that, The inorganic acid includes any one of hydrochloric acid, nitric acid or sulfuric acid; The mass ratio of the inorganic acid to the tetraalkoxysilane is 0.05-0.2:

1.

7. The preparation method according to claim 2, characterized in that, The reaction temperature of the hydrolysis and condensation in S1 is 60-160°C, and the reaction time is 4-12h; The solvent is removed by atmospheric high-temperature distillation, vacuum distillation or thin film evaporation.

8. The preparation method according to claim 2, characterized in that, In S2, the silicon-based amphiphilic random copolymer, the oil phase and water are stirred and mixed to encapsulate the oil phase with the silicon-based amphiphilic random copolymer to prepare a microemulsion; The mass ratio of the silicon-based amphiphilic random copolymer, the oil phase and water is 1:(1-4):(4-20); The oil phase is any one of n-heptane, n-hexane, cyclohexane, ethyl acetate, n-butyl acetate or toluene.

9. The preparation method according to claim 2, characterized in that, In S3, the microemulsion is subjected to a solidification reaction by alkali catalysis, specifically: The alkali catalyst is added to the microemulsion, the pH is adjusted to 10-11, and it is stirred uniformly; then it is heated to 80-90°C for solidification reaction; The alkali catalyst includes aqueous ammonia, aqueous sodium hydroxide or aqueous potassium hydroxide.

10. The method of claim 2, wherein, In S3, deionized water is used for washing; The drying comprises: heating the solid phase to 80-90 DEG C for 4-5 hours; and then heating to 130-140 DEG C for 3-4 hours.

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