Hybrid aerogel, hybrid aerogel coating and aerogel super-hydrophobic flame-retardant insulation board thereof

Abstract

The invention provides a hybrid aerogel, a hybrid aerogel coating and an aerogel super-hydrophobic flame-retardant heat preservation plate thereof. Silanol and layered silicate dispersion liquid are sequentially added into polyimide nanofiber turbid liquid to be stirred to obtain precursor turbid liquid, and aerogel is obtained after the precursor turbid liquid is frozen and dried; carrying out heat treatment on the aerogel to obtain hybrid aerogel; the hybrid aerogel is prepared into a hybrid aerogel coating; and coating the surface of the plate with the hybrid aerogel coating to obtain the aerogel super-hydrophobic flame-retardant insulation plate. According to the invention, aerogel is generated in situ between layers of layered silicate to form a sandwich structure, so that the dispersity of aerogel particles is improved; the polyimide nanofibers are nanofibers which are high in strength, excellent in high-temperature resistance and flame-retardant, play a role of reinforcing steel bars and anchor the aerogel particles into the layered silicate; the obtained aerogel particles have a super-hydrophobic effect, and the waterproof performance of an application product can be improved; the thermal insulation performance of the thermal insulation board is remarkably improved by adding the aerogel.

Description

Technical Field

[0001] This application belongs to the field of polymer materials, and particularly relates to a hybrid aerogel, a hybrid aerogel coating, and an aerogel superhydrophobic flame-retardant thermal insulation board. Background Art

[0002] The global energy crisis has made energy conservation a key area of concern for various industries. In the construction industry, the energy consumption of buildings accounts for a relatively high proportion, and a large part of it is due to heat transfer. To reduce energy consumption, high-performance thermal insulation materials have become a necessity.

[0003] Traditional thermal insulation materials have a certain thermal insulation performance. However, over time and under the influence of environmental factors, heat will still be dissipated through conduction, convection, and radiation. For example, in the case of rock wool thermal insulation boards, their fibrous structure gives them certain pores, which are prone to absorbing moisture when in contact with water. Once water is absorbed, it will not only increase the weight of the thermal insulation board itself but also cause a significant increase in its thermal conductivity. Because the thermal conductivity of water is much higher than that of air, when the pores are filled with water, heat is more likely to be transferred through the thermal insulation board, greatly reducing the insulation effect. Similar problems exist with aluminosilicate thermal insulation materials. They are prone to getting damp in a humid environment, resulting in a decline in thermal insulation performance. Moreover, the damp thermal insulation materials may also breed harmful substances such as mold, affecting the indoor air quality of buildings and the health of occupants.

[0004] At the same time, due to the urgent needs in the industrial field, superhydrophobic flame-retardant thermal insulation boards have broad application prospects. In the aerospace field, aircraft need to operate in extreme temperature environments. At high altitudes, the external temperature of the aircraft is extremely low, while the internal instruments and equipment generate heat, requiring high-performance thermal insulation materials to maintain temperature balance. At the same time, when passing through humid environments such as clouds, the thermal insulation materials will not fail due to water absorption. During the operation of high-temperature kilns, the internal temperature can reach thousands of degrees Celsius, requiring good thermal insulation materials to reduce heat loss and improve energy utilization efficiency. Moreover, the environment around the kilns may be relatively complex, including water vapor, dust, etc. Ordinary thermal insulation materials are easily damaged after water absorption, while superhydrophobic thermal insulation boards can effectively handle this situation. In the petrochemical industry, many pipelines and equipment need thermal insulation to ensure the temperature stability of the internal medium, prevent heat loss, or avoid external heat interference. The environments where these devices are located may contain various chemical substances and moisture, and superhydrophobic thermal insulation boards can prevent moisture from eroding the thermal insulation layer and ensure the normal operation of the equipment.

[0005] There are currently some publicly available materials on the application of aerogel materials in heat insulation and thermal insulation products. For example, in CN107267006A, silica aerogel materials are applied to coatings; however, the performance of similar products still has many deficiencies in actual applications and requires the additional addition of functional components such as flame retardants; the performance of aerogel materials themselves also needs to be improved. Summary of the Invention

[0006] To solve the above problems, the present application proposes a hybrid aerogel, a hybrid aerogel coating, and an aerogel superhydrophobic flame-retardant thermal insulation board. Among them, silanol and a layered silicate dispersion are sequentially added to a polyimide nanofiber suspension and stirred to obtain a precursor suspension. The precursor suspension is freeze-dried to obtain an aerogel, and the aerogel is then heat-treated to obtain a hybrid aerogel.

[0007] Preferably, the freeze-drying conditions of the precursor suspension are: cooling with liquid nitrogen and drying for 60 - 80 h.

[0008] Preferably, the heat-treatment conditions of the aerogel are: temperature 70 - 90 °C and time 3 - 5 h.

[0009] Furthermore, a silane coupling agent is added to an acid and stirred to hydrolyze to form the silanol; the silane coupling agent is one or a combination of methyltrimethoxysilane, vinyltrimethoxysilane, KH550, KH792, KH602; the acid is acetic acid or hydrochloric acid, preferably acetic acid; the volume ratio of the silane coupling agent to the acid is 1:(0.1 - 10).

[0010] Preferably, the silane coupling agent is selected as a compound of methyltrimethoxysilane and vinyltrimethoxysilane, and the optimal volume ratio is 1:1.

[0011] Furthermore, the layered silicate is one or a combination of montmorillonite, talc, and muscovite.

[0012] Preferably, the layered silicate is montmorillonite and muscovite, and the optimal mass ratio is 2:1.

[0013] Furthermore, the mass ratio of the layered silicate to water in the layered silicate dispersion is 1:(1 - 200);

[0014] Furthermore, the volume ratio of the silanol to the layered silicate dispersion is 1:(0.1 - 20).

[0015] Furthermore, the content of polyimide nanofibers in the polyimide nanofiber suspension is 0.2 wt% - 0.4 wt%; the volume ratio of the layered silicate dispersion to the polyimide nanofiber suspension is 1:(1 - 200).

[0016] Furthermore, the layered silicate is heat-treated at 200 - 600 °C for 80 - 120 min and then dispersed in water, and magnetically stirred at 70 - 90 °C for 3 - 5 h to obtain the layered silicate dispersion.

[0017] The present application also provides a hybrid aerogel coating, which includes the following components: the hybrid aerogel prepared in the present application, an emulsion, a dispersant, and a thickener;

[0018] The mass ratio of the hybrid aerogel to the emulsion is 1:(1 - 500); the dispersant is 0.1 - 10% of the mass of the emulsion, and the thickener is 0.1 - 10% of the mass of the emulsion.

[0019] Further, the emulsion is one or a combination of epoxy resin, silicon acrylic resin, pure acrylic resin, and polyurethane.

[0020] Further, the dispersant is sodium hexametaphosphate or sodium polyphosphate;

[0021] Further, the thickener is hydroxyethyl cellulose or polyurethane thickener.

[0022] This application also provides an aerogel superhydrophobic flame-retardant thermal insulation board. After drying the hybrid aerogel coating prepared in this application on the surface of the board, the aerogel superhydrophobic flame-retardant thermal insulation board is obtained.

[0023] Preferably, the drying temperature is 60 - 200 °C.

[0024] Preferably, the coating thickness of the coating is 0.8 - 1.2 mm.

[0025] Preferably, the board of the thermal insulation board in this application can be made of inorganic non-metallic materials such as cement board, calcium silicate board, and ceramic board; it can be made of organic polymer materials such as polystyrene board, extruded polystyrene board, and polyurethane board; it can be made of metal materials such as aluminum plate and steel plate.

[0026] This application can bring the following beneficial effects:

[0027] 1. In this invention, aerogel is in-situ generated between the interlayers of layered silicate to form a sandwich structure, which improves the dispersibility of aerogel particles; polyimide nanofibers are nanofibers with high strength, excellent high-temperature resistance, and flame retardancy, playing the role of "steel bars" to anchor the aerogel particles in the layered silicate; the aerogel particles have superhydrophobic effects, which can improve the waterproof performance of the applied products.

[0028] 2. The polycondensation reaction of silanol is used to form a hydrophobic layer containing siloxane groups on the surface of the aerogel; and the layered silicate can reduce the polarity of the aerogel surface, further enhancing the hydrophobicity of the aerogel; there are many active groups on the polyimide molecular chain, which can chemically or physically interact with silanol and layered silicate, facilitating the formation of a stable hybrid structure and improving the comprehensive performance of the aerogel.

[0029] 3. Polyimide nanofibers can form a stable carbonized layer at high temperatures to hinder the transfer of heat and oxygen. Additionally, layered silicate can form a barrier layer during combustion to inhibit the release of combustible gases and heat transfer. The silicon element of silanol generates substances such as silicon dioxide during the combustion process, which helps to improve the stability of the carbon layer and enhance the flame retardancy effect.

[0030] 4. There are a large number of nanoscale pores inside the aerogel, and the air in the pores is restricted to reduce convective heat transfer by air. The hybrid aerogel of this application forms a three-dimensional network structure, which can inhibit heat conduction. At the same time, it has an absorption and scattering effect on infrared radiation, which can reduce heat radiation heat transfer and achieve an efficient heat insulation effect.

[0031] 5. The performance of the hybrid aerogel obtained by hybridizing different materials is significantly improved, and specific hydrophobicity, flame retardancy, and heat insulation can be achieved. It can be applied in multiple fields, such as the heat insulation structural materials required in aerospace, and the exterior wall insulation and roof heat insulation that require heat insulation and hydrophobicity in the construction field.

[0032] 6. Polyimide nanofibers have a large specific surface area, which can provide more sites for the attachment and dispersion of components such as silanol and layered silicate, facilitating the formation of a uniform hybrid structure and increasing the interfacial interaction inside the aerogel. Additionally, the interwoven nanofibers can form nanoscale pores, which cooperate with the porous structure of the aerogel to improve the performance of the aerogel.

[0033] 7. The preparation method of the hybrid aerogel of this application is simple and easy to scale up production. By adding appropriate other components, it can be made into a coating product and coated on a board to prepare a heat insulation board. The product has excellent performance and great market application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The drawings described herein are used to provide a further understanding of the present application and form a part of the present application. The schematic embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation of the present application. In the drawings:

[0035] Figure 1 It is a contact angle picture of the superhydrophobic flame retardant heat insulation board of the aerogel in Example 1. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0036] Unless otherwise specified, the reagents and instruments used in the following examples are all commercially available products.

[0037]

Example 1

[0038] A hybrid aerogel in this example was prepared by the following preparation method:

[0039] Montmorillonite was heat-treated at 450 °C for 100 min, and then the obtained material was dispersed in water. The mass ratio of montmorillonite to water was 1:100, and it was magnetically stirred at 80 °C at a speed of 300 r·min -1 for 4 hours to form a uniform montmorillonite dispersion. Subsequently, 1 mL of methyltrimethoxysilane and 1 mL of vinyltrimethoxysilane were added to 3 mL of acetic acid and stirred for 2 hours to hydrolyze and generate silanol. Then, 1 mL of silanol and 1 mL of montmorillonite dispersion were successively added to 5 mL of a 0.3 wt% polyimide nanofiber suspension, and stirred at room temperature for 1 hour to form a uniform precursor suspension.

[0040] An appropriate amount of the precursor suspension was placed in a mold, cooled with liquid nitrogen, and freeze-dried for 72 hours. Finally, the obtained aerogel was heat-treated in an oven at 80 °C for 4 hours to obtain a hybrid aerogel.

[0041]

Example 2

[0042] A hybrid aerogel in this example was prepared by the following preparation method:

[0043] Talc was heat-treated at 200 °C for 120 min, and then the obtained material was dispersed in water. The mass ratio of talc to water was 1:1, and it was magnetically stirred at 90 °C at a speed of 400 r·min -1 for 3 hours to form a uniform talc dispersion. Subsequently, 1 mL of KH550 was added to 0.1 mL of hydrochloric acid and stirred for 1 hour to hydrolyze and generate silanol. Then, 1 mL of silanol and 0.1 mL of talc dispersion were successively added to 20 ml of a 0.4 wt% polyimide nanofiber suspension, and stirred at room temperature for 1 hour to form a uniform precursor suspension.

[0044] An appropriate amount of the precursor suspension was placed in a mold, cooled with liquid nitrogen, and freeze-dried for 60 hours. Finally, the obtained aerogel was heat-treated in an oven at 70 °C for 5 hours to obtain a hybrid aerogel.

[0045]

Example 3

[0046] A hybrid aerogel in this example was prepared by the following preparation method:

[0047] Muscovite was heat-treated at 600 °C for 80 min, and then the obtained material was dispersed in water. The mass ratio of muscovite to water was 1:200, and it was magnetically stirred at 70 °C at a speed of 350 r·min -1Magnetically stir at a speed of 5 hours to form a uniform muscovite dispersion. Subsequently, add 1 mL of KH792 to 10 mL of acetic acid and stir for 2 hours to hydrolyze it to form silanol. Then, add 1 mL of silanol and 20 mL of muscovite dispersion to 20 mL of 0.2 wt% polyimide nanofiber suspension in sequence, and stir at room temperature for 2 hours to form a uniform precursor suspension.

[0048] Place an appropriate amount of the precursor suspension in a mold, cool it with liquid nitrogen, and freeze-dry for 80 hours. Finally, heat-treat the obtained aerogel in an oven at 90 °C for 3 hours to obtain the hybrid aerogel.

[0049]

Example 4

[0050] Heat-treat montmorillonite at 500 °C for 100 min, then disperse the obtained material in water, and magnetically stir at a speed of 400 r·min -1 at 80 °C for 4 hours to form a uniform montmorillonite dispersion. Subsequently, add 2 mL of methyltrimethoxysilane to 5 mL of acetic acid and stir for 2 hours to hydrolyze it to form silanol. Then, add 1 mL of silanol and 1 mL of montmorillonite dispersion to 5 mL of 0.3 wt% polyimide nanofiber suspension in sequence, and stir at room temperature for 1 hour to form a uniform precursor suspension.

[0051] Place an appropriate amount of the precursor suspension in a mold, cool it with liquid nitrogen. Freeze-dry for 72 hours. Finally, heat-treat the obtained aerogel in an oven at 80 °C for 4 hours to obtain the hybrid aerogel.

[0052]

Example 5

[0053] Heat-treat montmorillonite at 600 °C for 100 min, and then disperse the obtained material in water, and magnetically stir at a speed of 300 r·min -1 at 80 °C for 4 hours to form a uniform montmorillonite dispersion. Subsequently, add 2 mL of vinyltrimethoxysilane to 6 mL of acetic acid and stir for 2 hours to hydrolyze it to form silanol. Then, add 1 mL of silanol and 1 mL of montmorillonite dispersion to 6 mL of 0.3 wt% polyimide nanofiber suspension in sequence, and stir at room temperature for 1 hour to form a uniform precursor suspension.

[0054] Place an appropriate amount of the precursor suspension in a mold, cool it with liquid nitrogen. Freeze-dry for 72 hours. Finally, heat-treat the obtained aerogel in an oven at 80 °C for 4 hours to obtain the hybrid aerogel.

[0055]

Example 6

[0056] A hybrid aerogel in this example is prepared by the following preparation method:

[0057] Montmorillonite and muscovite (mass ratio 2:1) were heat-treated at 500 °C for 100 min, and then the obtained material was dispersed in water. The mass ratio of the composite layered silicate to water was 1:150, and it was magnetically stirred at 80 °C at a speed of 400 r·min -1 for 4 h to form a uniform composite layered silicate dispersion. Subsequently, 1 mL of methyltrimethoxysilane and 1 mL of vinyltrimethoxysilane were added to 3 mL of acetic acid and stirred for 2 h to hydrolyze and generate silanol. Then, 1 mL of silanol and 1 mL of the composite layered silicate dispersion were successively added to 5 mL of a 0.3 wt% polyimide nanofiber suspension, and stirred at room temperature for 2 h to form a uniform precursor suspension.

[0058] An appropriate amount of the precursor suspension was placed in a mold, cooled with liquid nitrogen, and freeze-dried for 80 h. Finally, the obtained aerogel was heat-treated in an oven at 80 °C for 4 h to obtain a hybrid aerogel.

[0059]

Comparative Example 1

[0060] The difference between Comparative Example 1 and Example 1 was only that layered silicate was not added during the preparation process. The specific preparation method was as follows:

[0061] 1 mL of methyltrimethoxysilane and 1 mL of vinyltrimethoxysilane were added to 3 mL of acetic acid and stirred for 2 h to hydrolyze and generate silanol. Then, 1 mL of silanol was added to 5 mL of a 0.3 wt% polyimide nanofiber suspension and stirred at room temperature for 1 h to form a uniform precursor suspension.

[0062] An appropriate amount of the precursor suspension was placed in a mold, cooled with liquid nitrogen, and freeze-dried for 72 h. Finally, the obtained aerogel was heat-treated in an oven at 80 °C for 4 h to obtain an aerogel.

[0063]

Comparative Example 2

[0064] The difference between Comparative Example 2 and Example 1 was only that polyimide nanofibers were not added during the preparation process. The preparation method was as follows:

[0065] Montmorillonite was heat-treated at 450 °C for 100 min, and then the obtained material was dispersed in water. The mass ratio of montmorillonite to water was 1:100, and it was magnetically stirred at 80 °C at a speed of 300 r·min -1 for 4 h to form a uniform montmorillonite dispersion. Subsequently, 1 mL of methyltrimethoxysilane and 1 mL of vinyltrimethoxysilane were added to 3 mL of acetic acid solution and stirred for 2 h to hydrolyze and generate silanol. 1 mL of silanol and 1 mL of the montmorillonite dispersion were successively added to 5 mL of water and stirred at room temperature for 1 h to form a uniform precursor suspension.

[0066] An appropriate amount of the precursor suspension was placed in a mold, cooled with liquid nitrogen, and freeze-dried for 72 hours. Finally, the obtained aerogel was heat-treated in an oven at 80 °C for 4 hours to obtain the hybrid aerogel.

[0067]

Comparative Example 3

[0068] The difference between Comparative Example 3 and Example 1 is only that no silanol is added during the preparation process. The preparation method is as follows:

[0069] Montmorillonite was heat-treated at 450 °C for 100 min, and then the obtained material was dispersed in water. The mass ratio of montmorillonite to water was 1:100, and it was magnetically stirred at 80 °C at a speed of 300 r·min -1 for 4 hours to form a uniform montmorillonite dispersion. 2 mL of the montmorillonite dispersion was added to 5 mL of a 0.3 wt% polyimide nanofiber suspension, and stirred at room temperature for 1 hour to form a uniform precursor suspension.

[0070] An appropriate amount of the precursor suspension was placed in a mold, cooled with liquid nitrogen, and freeze-dried for 72 hours. Finally, the obtained aerogel was heat-treated in an oven at 80 °C for 4 hours to obtain the hybrid aerogel.

[0071]

Comparative Example 4

[0072] The difference between Comparative Example 4 and Example 1 is only that the polyimide nanofibers are replaced with basalt fibers during the preparation process.

[0073] The present application also provides a hybrid aerogel coating, the components of which include a hybrid aerogel, an emulsion, a dispersant, and a thickener. The preparation method is as follows:

[0074] The hybrid aerogel was crushed, and an appropriate amount was added to the emulsion. Then, a dispersant and a thickener were added and stirred to obtain the hybrid aerogel coating. The mass ratio of the hybrid aerogel to the emulsion was 1:(1 - 500); the dispersant was 0.1 - 10% of the mass of the emulsion, and the thickener was 0.1 - 10% of the mass of the emulsion.

[0075] The emulsion is selected from one or a combination of epoxy resin, silicone-acrylic resin, pure acrylic resin, and polyurethane;

[0076] The dispersant is selected from sodium hexametaphosphate or sodium polyphosphate;

[0077] The thickener is selected from hydroxyethyl cellulose or polyurethane thickener.

[0078] Through experiments, it will be found that the selection of emulsion, dispersant, and thickener in the coating is a relatively optimal solution obtained through multiple experimental demonstrations. Through experiments, it is found that if the emulsion is replaced with other resins commonly used in coatings, such as acrylic resin and phenolic resin; or the dispersant is replaced with other components such as carboxylate and quaternary ammonium salt; or the thickener is replaced with other components such as polyacrylic acid and starch, the performance of the final product insulation board (heat preservation, hydrophobicity, flame retardancy, aerogel stability) will decline, indicating that the selection of each component of the coating in this application will affect the compatibility with the hybrid aerogel or other components, and thus affect the performance of the overall product.

[0079] This application also provides an aerogel superhydrophobic flame-retardant insulation board. The preparation method includes roll-coating or spraying the hybrid aerogel coating on the surface of the board, with a coating thickness of 0.8 - 1.2 mm, and obtaining the aerogel superhydrophobic flame-retardant insulation board after drying.

[0080] To demonstrate the experimental effect, the following examples use polystyrene board as the board material, and the actual application is not limited to this board.

[0081] To demonstrate the experimental effect, the components and ratios of the hybrid aerogel coating are not shown in detail, and only the preferred parts are shown.

[0082] The insulation boards obtained in the following examples are respectively prepared by taking 1 g of the hybrid aerogels obtained from Examples 1 - 6 and Comparative Examples 1 - 4, adding them to 10 g of aqueous epoxy resin emulsion, and then adding 0.1 g of sodium hexametaphosphate and 0.1 g of hydroxyethyl cellulose to obtain the hybrid aerogel coating, which is roll-coated on the polystyrene board (coating thickness is 0.8 mm) to obtain insulation boards 1 - 6 and comparison boards 1 - 4.

[0083]

Characterization of Aerogel Superhydrophobic Flame-Retardant Insulation Board

[0084] The following characterizations are carried out on the aerogel superhydrophobic flame-retardant insulation boards 1 - 6 and comparison boards 1 - 4:

[0085] 1. Heat preservation effect: Test using a transient plane heat source method thermal conductivity meter to obtain the thermal conductivity;

[0086] 2. Hydrophobicity: Test using a contact angle measuring instrument to obtain the contact angle;

[0087] 3. Flame retardancy: Obtain the flame retardancy level according to the national standard GB 8624-2012 "Classification of Combustion Performance of Building Materials and Products";

[0088] 4. Aerogel particle stability test: Wipe the surface of the insulation board with 400-mesh sandpaper and observe whether there are particles falling off.

[0089]

[0090] From the characterization results in the above table, it can be obtained that: for the hybrid aerogel obtained in this application, when combined with other components to prepare a coating, the hybrid aerogel can be very uniformly distributed in the coating, and it has very good coatability when applied on the insulation board, and the aerogel particles are very stably fixed on the board; the obtained insulation board has good heat insulation performance, good hydrophobicity, and a certain flame retardant effect.

[0091] The results of Comparative Examples 1 - 3 show that the addition of layered silicate, polyimide nanofiber, and silanol has a great influence on the product performance, and the hybrid aerogel material obtained by combining these technical solutions has excellent performance.

[0092] The result of Comparative Example 4 shows that when replacing the polyimide nanofiber with basalt fiber, the fiber dispersion is not good, and the compatibility with other components is not good, and the obtained hybrid aerogel cannot be uniformly dispersed in the coating, which affects the performance of the final product.

[0093] Each embodiment in this specification is described in a progressive manner. For the same or similar parts among the embodiments, reference can be made to each other, and the key point of each embodiment is to illustrate the differences from other embodiments. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and reference can be made to the relevant part of the method embodiment for the relevant content.

[0094] The above are only the embodiments of the present application and are not used to limit the present application. For those skilled in the art, various changes and modifications can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the scope of the claims of the present application.

Claims

1. A hybrid aerogel, characterized in that: The silanol and layered silicate dispersions are sequentially added to the polyimide nanofiber suspension and stirred to obtain a precursor suspension. The precursor suspension is freeze-dried to obtain an aerogel, and the aerogel is heat-treated to obtain a hybrid aerogel.

2. A hybrid aerogel according to claim 1, characterized in that: Adding a silane coupling agent into an acid and stirring to hydrolyze it to generate the silanol; The silane coupling agent is one or a combination of methyltrimethoxysilane, vinyltrimethoxysilane, KH550, KH792, and KH602; The acid is acetic acid or hydrochloric acid, preferably acetic acid; The volume ratio of the silane coupling agent to the acid is 1:(0.1-10).

3. A hybrid aerogel according to claim 1, characterized in that: The layered silicate is one or a combination of montmorillonite, talc and muscovite.

4. A hybrid aerogel according to claim 3, characterized in that: The layered silicate is montmorillonite and muscovite, with a mass ratio of 2:

1.

5. The hybrid aerogel according to claim 1, characterized in that: The mass ratio of layered silicate to water in the layered silicate dispersion is 1:(1-200); The volume ratio of the silanol to the layered silicate dispersion is 1:(0.1-20).

6. The hybrid aerogel according to claim 1, characterized in that: The polyimide nanofiber content in the polyimide nanofiber suspension is 0.2-0.4wt%; the volume ratio of the layered silicate dispersion to the polyimide nanofiber suspension is 1:(1-200).

7. The hybrid aerogel according to claim 1, characterized in that: The layered silicate is heat treated at 200-600°C for 80-120 minutes, dispersed in water, and magnetically stirred at 70-90°C for 3-5 hours to obtain a layered silicate dispersion.

8. A hybrid aerogel coating, characterized in that: The invention comprises the following components: the hybrid aerogel according to any one of claims 1 to 7, an emulsion, a dispersant, and a thickener; The mass ratio of the hybrid aerogel to the emulsion is 1:(1-500); the dispersant accounts for 0.1-10% of the mass of the emulsion, and the thickener accounts for 0.1-10% of the mass of the emulsion.

9. The hybrid aerogel coating according to claim 8, characterized in that: The emulsion is one or a combination of epoxy resin, silicone-acrylic resin, pure acrylic resin, and polyurethane; The dispersant is sodium hexametaphosphate or sodium polyphosphate; The thickener is hydroxyethyl cellulose or polyurethane thickener.

10. An aerogel super hydrophobic flame retardant insulation board, characterized in that: The hybrid aerogel coating according to any one of claims 8 to 9 is coated on the surface of the board and then dried to obtain an aerogel super hydrophobic flame retardant thermal insulation board, wherein the coating thickness is 0.8 to 1.2 mm.

Images