Interface enhanced aerogel-silicate composite coating and preparation method thereof

Abstract

The invention discloses an interface enhanced aerogel-silicate composite coating. The interface enhanced aerogel-silicate composite coating is prepared from the following components: hydrophobic silicon dioxide aerogel, modified layered silicate, an interface enhancer and epoxy-organic silicon resin. The invention discloses a preparation method of an interface enhanced aerogel-silicate composite coating. The preparation method comprises the following steps: (1) preparing hydrophobic silicon dioxide aerogel; (2) preparing modified layered silicate; (3) preparing an interface reinforcing agent; (4) mixing the hydrophobic silicon dioxide aerogel, the modified layered silicate and an interface reinforcing agent into a mixture; and (5) adding epoxy-organic silicon resin into the mixture. According to the interface-enhanced aerogel-silicate composite coating and the preparation method thereof, the material has good adhesive force and moisture-proof effect, can effectively inhibit bacteria to prevent wall surfaces from mildewing, and can automatically repair micro-cracks at the same time.

Description

Technical Field

[0001] This application relates to the field of coatings, and more specifically to an interface-enhanced aerogel-silicate composite coating and its preparation method. Background Art

[0002] Aerogel refers to a nano-porous solid material formed by replacing the liquid phase in a gel with gas through the sol-gel method and a certain drying method. It is the solid with the lowest density in the world and one of the top ten emerging technologies in the field of chemistry in 2022. Due to the good heat insulation and sound insulation capabilities of aerogel, various building material enterprises are exploring the application of aerogel in the building material industry. Summary of the Invention

[0003] Aiming at the deficiencies of the prior art, this application provides an interface-enhanced aerogel-silicate composite coating and its preparation method. This material has good adhesion and moisture-proof effects, can effectively inhibit bacteria to avoid wall mildew, and can also automatically repair micro-cracks.

[0004] An interface-enhanced aerogel-silicate composite coating, the components of which include hydrophobic silica aerogel, modified layered silicate, interface enhancer, and epoxy-organosilicon resin;

[0005] The weight parts of each component are as follows:

[0006] Hydrophobic silica aerogel 10 - 20 parts;

[0007] Modified layered silicate 30 - 50 parts;

[0008] Interface enhancer 5 - 10 parts;

[0009] Epoxy-organosilicon resin 20 - 40 parts.

[0010] Preferably, the density of the hydrophobic silica aerogel is 0.08 - 0.15 g / cm 3 and the contact angle ≥ 140°.

[0011] Preferably, the modified layered silicate is CTAB intercalated montmorillonite loaded with ZnO, and the loading amount of ZnO is 5 - 12%.

[0012] Preferably, the interface enhancer is a composite system of silane coupling agent and nano-silica, and the silane coupling agent is KH550 or KH560.

[0013] A preparation method of an interface-enhanced aerogel-silicate composite coating includes the following steps:

[0014] (1) Prepare hydrophobic silica aerogel;

[0015] (2) Prepare the modified layered silicate;

[0016] (3) Prepare the interface enhancer;

[0017] (4) Mix the hydrophobic silica aerogel, the modified layered silicate and the interface enhancer into a mixture;

[0018] (5) Add epoxy - silicone resin to the mixture.

[0019] The specific preparation process of the hydrophobic silica aerogel described in step (1) is as follows:

[0020] (11) Pretreat the aerogel;

[0021] (11a) Immerse the aerogel in n - hexane and perform ultrasonic treatment for 30 minutes to open the pores and remove surface impurities;

[0022] (11b) Place the aerogel treated in step (11a) in a vacuum drying oven at 60 °C and dry for 2 hours to remove the residual solvent;

[0023] (12) Prepare the modified solution;

[0024] (12a) Dissolve FAS in n - hexane to prepare a 5 wt% solution;

[0025] (12b) Stir magnetically for 30 minutes to ensure uniform mixing and obtain the modified solution;

[0026] (13) In a vacuum container, immerse the pretreated aerogel in the modified solution, then evacuate to 10 kPa and maintain for 1 hour to promote the penetration of the modified solution into the pores of the aerogel;

[0027] (14) After releasing the vacuum, let it stand and react in a constant - temperature environment at 40 °C for 6 hours to allow the FAS in the modified solution to fully react with the hydroxyl groups on the surface of the aerogel;

[0028] (15) Wash the aerogel;

[0029] (15a) Take out the aerogel, ultrasonically clean it with n - hexane for 10 minutes and repeat 3 times to remove the unreacted FAS;

[0030] (15b) Then wash it twice with absolute ethanol to ensure no residue on the surface;

[0031] (16) Place the washed aerogel in a vacuum drying oven at 60 °C and dry for 12 hours to completely remove the solvent and obtain the hydrophobic silica aerogel.

[0032] The specific preparation process of the modified layered silicate described in step (2) is as follows:

[0033] (21) Disperse montmorillonite powder in deionized water at a solid-liquid ratio of 1:20, and ultrasonically treat for 30 minutes until completely dispersed to obtain a montmorillonite powder solution;

[0034] (22) Add CTAB to the montmorillonite powder solution at a plasmid ratio of CTAB:montmorillonite = 1:0.5, raise the temperature to 60 °C under stirring, and stir and react at 60 °C for 6 hours to obtain a first reaction solution;

[0035] (23) Centrifuge the first reaction solution at a speed of 8000 rpm for 10 minutes, discard the supernatant, wash the solid with deionized water until there is no residual Br-, then vacuum dry at 60 °C for 12 h, and finally grind it into intercalated montmorillonite with a particle size ≤ 50 μm;

[0036] (24) Dissolve zinc nitrate in deionized water to form a solution with a concentration of 0.5 M, and add ammonia water to adjust the pH to 9.0 to obtain a zinc nitrate solution;

[0037] (25) Disperse the intercalated montmorillonite in the zinc nitrate solution at a solid-liquid ratio of 1:10, and stir and react at 80 °C for 4 hours to obtain a second reaction solution;

[0038] (26) Centrifuge the second reaction solution at a speed of 8000 rpm for 10 minutes, discard the supernatant, wash it 3 times with deionized water and 1 time with ethanol, pre-dry at 60 °C, and finally calcine at 350 °C for 2 hours to form ZnO nanoparticles, thereby obtaining modified layered silicate;

[0039] The heating rate during the calcination process is 5 °C / min.

[0040] The preparation process of the interfacial enhancer described in step (3) is as follows:

[0041] (31) Mix the silane coupling agent and absolute ethanol at a volume ratio of 1:5, add deionized water and adjust the pH to 4 - 5 with acetic acid, and hydrolyze for 30 min to form a pre-hydrolyzed solution;

[0042] (32) Add nano-silica powder to ethanol at a solid-liquid ratio of 1:10, ultrasonically treat for 30 min under the condition of a power of 300 W to form a uniformly dispersed solution; add the pre-hydrolyzed solution, and continue to ultrasonically treat for 1 h to obtain a first mixed solution;

[0043] Among them, the mass ratio of silica:silane coupling agent = 1:1 - 3:1;

[0044] (33) Transfer the first mixture into a ball milling tank, add zirconia ball milling beads with a diameter of 3 - 5 mm, and the ball-to-material ratio is 5:1; ball mill for 2 - 4 hours at a rotation speed of 400 - 600 rpm to ensure that the nano-silica is evenly dispersed and fully bonded with the silane coupling agent;

[0045] (34) Add 0.5 - 1 wt% propylene oxide as a crosslinking agent and stir and react at 60°C for 1 hour to enhance the system stability and obtain a second mixture;

[0046] (35) Vacuum filter the second mixture to remove the excess ethanol, vacuum dry at 60°C for 12 hours, and obtain an interface enhancer with a particle size ≤ 50 μm after grinding and sieving.

[0047] In step (4), the hydrophobic silica aerogel, the modified layered silicate and the interface enhancer are mixed and then ground by a ball mill to a mixture with a particle size ≤ 50 μm.

[0048] In step (5), the viscosity of the mixture is adjusted to 3000 - 8000 mPa·s by adding epoxy-organosilicon resin.

[0049] Compared with the prior art, the embodiments of the present application have the following beneficial effects:

[0050] The materials of the present invention have good adhesion and moisture-proof effects, can effectively inhibit bacteria to avoid wall mildew, and can also automatically repair micro-cracks.

[0051] Some additional features of the present application can be described below. Through the examination of the following description and the corresponding drawings or the understanding of the production or operation of the embodiments, some additional features of the present application are obvious to those skilled in the art. The features disclosed in the present application can be realized and achieved through the practice or use of various methods, means and combinations of the specific embodiments described below. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] The drawings described herein are used to provide a further understanding of the present application, and constitute 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 a limitation to the present application. In each figure, the same reference numerals represent the same components. Among them,

[0053] Figure 1 is a step diagram of the preparation method of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0054] To enable those skilled in the art to better understand the solution of this application, the following will clearly and completely describe the technical solution in the embodiments of this application in conjunction with the accompanying drawings in the embodiments of this application. Obviously, the described embodiments are only a part of the embodiments of this application, rather than all the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of this application.

[0055] It should be noted that if the terms "first", "second", etc. are involved in the description and claims of this application and the above-mentioned drawings, they are used to distinguish similar objects and do not necessarily have to be used to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances for the embodiments of this application described herein. In addition, if the terms "include" and "have" and any of their variants are involved, the intention is to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0056] In this application, if the terms "upper", "lower", "left", "right", "front", "rear", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal", etc. are involved, the orientation or positional relationship indicated is based on the orientation or positional relationship shown in the drawings. These terms are mainly used to better describe this application and its embodiments, and are not used to limit that the indicated device, element or component must have a specific orientation or be constructed and operated in a specific orientation.

[0057] Moreover, in addition to being able to represent an orientation or positional relationship, some of the above terms may also be used to represent other meanings. For example, the term "upper" may also be used to represent a certain attachment relationship or connection relationship in some cases. For those of ordinary skill in the art, the specific meanings of these terms in this application can be understood according to specific circumstances.

[0058] In addition, in this application, if the terms "install", "set", "be provided with", "connect", "be connected", "be sleeved" etc. are involved, they should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or there can also be internal communication between two devices, elements or components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0059] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0060] Example 1

[0061] An interface-enhanced aerogel-silicate composite coating and its preparation method, the components include hydrophobic silica aerogel, modified layered silicate, interface enhancer, and epoxy-organosilicon resin;

[0062] The weight parts of each component are:

[0063] Hydrophobic silica aerogel 10 parts;

[0064] Modified layered silicate 30 parts;

[0065] Interface enhancer 5 parts;

[0066] Epoxy-organosilicon resin 20 parts.

[0067] The density of the hydrophobic silica aerogel is 0.08 - 0.15 g / cm 3 , and the contact angle ≥ 140°.

[0068] The modified layered silicate is CTAB intercalated montmorillonite loaded with ZnO, and the loading amount of ZnO is 5 - 12%.

[0069] The interface enhancer is a composite system of silane coupling agent and nano-silica, and the silane coupling agent is KH550 or KH560.

[0070] The characteristics of the above product are as follows:

[0071] (1) Moisture-proof property: The modified layered silicate can effectively prevent the penetration of liquid water, and the hydrophobic silica aerogel can adsorb the infiltrated moisture, and its water absorption rate ≥ 20%.

[0072] (2) Antibacterial property: Since the modified layered silicate is loaded with ZnO, it can slowly release zinc ions during use, and the zinc ions can effectively damage the cell membrane of molds, thus achieving the antibacterial effect, and its antibacterial rate ≥ 85%.

[0073] (3) Anti-cracking and repair property: The interface enhancer can effectively improve the bonding force between the product and the wall substrate, and can also repair micro-cracks below 0.2 mm.

[0074] Example 2

[0075] The difference between this example and Example 1 is that the weight parts of each component are:

[0076] 20 parts of hydrophobic silica aerogel;

[0077] 50 parts of modified layered silicate;

[0078] 10 parts of interface enhancer;

[0079] 40 parts of epoxy - silicone resin.

[0080] Example 3

[0081] The difference between this example and Example 1 is that the weight parts of each component are:

[0082] 15 parts of hydrophobic silica aerogel;

[0083] 40 parts of modified layered silicate;

[0084] 7 parts of interface enhancer;

[0085] 30 parts of epoxy - silicone resin.

[0086] Example 4

[0087] A preparation method of an interface - enhanced aerogel - silicate composite coating, comprising the following steps:

[0088] (1) Prepare hydrophobic silica aerogel;

[0089] The specific preparation process of the described hydrophobic silica aerogel is as follows:

[0090] (11) Pretreat the aerogel;

[0091] (11a) Immerse the aerogel in n - hexane and perform ultrasonic treatment for 30 minutes to open the pores and remove surface impurities;

[0092] (11b) Place the aerogel treated in step (11a) in a vacuum drying oven at 60 °C and dry for 2 hours to remove residual solvent;

[0093] (12) Prepare a modified solution;

[0094] (12a) Dissolve FAS in n - hexane to prepare a 5 wt% solution;

[0095] (12b) Stir magnetically for 30 minutes to ensure uniform mixing and obtain a modified solution;

[0096] (13) In a vacuum container, immerse the pretreated aerogel in the modified solution, then evacuate to 10 kPa and hold for 1 hour to promote the penetration of the modified solution into the pores of the aerogel;

[0097] (14) After releasing the vacuum, it is left to react for 6 hours in a constant temperature environment of 40 °C to allow the FAS in the modified solution to fully react with the hydroxyl groups on the surface of the aerogel;

[0098] (15) Wash the aerogel;

[0099] (15a) Take out the aerogel, ultrasonically clean it with n-hexane for 10 minutes, and repeat 3 times to remove the unreacted FAS;

[0100] (15b) Then wash it twice with absolute ethanol to ensure no residue on the surface;

[0101] (16) Place the washed aerogel in a vacuum drying oven at 60 °C and dry it for 12 hours. After thoroughly removing the solvent, hydrophobic silica aerogel is obtained.

[0102] Hydrophobic silica aerogel is a prior art and can also be directly purchased for use, such as Sailike hydrophobic silica aerogel.

[0103] (2) Prepare the modified layered silicate;

[0104] The specific preparation process of the described modified layered silicate is as follows:

[0105] (21) Disperse montmorillonite powder in deionized water at a solid-liquid ratio of 1:20, and ultrasonically treat it for 30 minutes until completely dispersed to obtain a montmorillonite powder solution;

[0106] (22) Add CTAB to the montmorillonite powder solution at a plasmid ratio of CTAB:montmorillonite = 1:0.5, raise the temperature to 60 °C under stirring, and stir and react at 60 °C for 6 hours to obtain the first reaction solution;

[0107] (23) Centrifuge the first reaction solution at a speed of 8000 rpm for 10 minutes, then discard the supernatant, wash the solid with deionized water until there is no Br- residue, then vacuum dry it at 60 °C for 12 h, and finally grind it into intercalated montmorillonite with a particle size ≤ 50 μm;

[0108] (24) Dissolve zinc nitrate in deionized water to form a solution with a concentration of 0.5 M, and add ammonia water to adjust the pH to 9.0 zinc nitrate solution;

[0109] (25) Disperse the intercalated montmorillonite in the zinc nitrate solution at a solid-liquid ratio of 1:10, and stir and react at 80 °C for 4 hours to obtain the second reaction solution;

[0110] Centrifuge the second reaction solution at a speed of 8000 rpm for 10 minutes, discard the supernatant, wash it 3 times with deionized water and 1 time with ethanol, pre-dry it at a temperature of 60 °C, and finally calcine it at a temperature of 350 °C for 2 hours to form ZnO nanoparticles, thereby obtaining modified layered silicate;

[0111] The heating rate during calcination is 5 °C / min.

[0112] (3) Prepare an interface enhancer;

[0113] The preparation process of the described interface enhancer is as follows:

[0114] (31) Mix the silane coupling agent and absolute ethanol in a volume ratio of 1:5, add deionized water and adjust the pH to 4 with acetic acid, and hydrolyze for 30 min to form a pre-hydrolyzed solution;

[0115] (32) Add nano-silica powder to ethanol at a solid-liquid ratio of 1:10, and ultrasonically treat it for 30 min under the condition of a power of 300 W to form a uniformly dispersed solution; add the pre-hydrolyzed solution and continue ultrasonically treating it for 1 h to obtain a first mixed solution;

[0116] Where the mass ratio of silica to silane coupling agent is 1:1;

[0117] (33) Transfer the first mixed solution to a ball mill tank, add zirconia ball mill beads with a diameter of 3 mm, and the ball-to-material ratio is 5:1; ball mill for 2 hours during rotation at 400 rpm to ensure that nano-silica is uniformly dispersed and fully bonded with the silane coupling agent;

[0118] (34) Add 0.5 wt% propylene oxide as a crosslinking agent and stir and react at 60 °C for 1 hour to enhance the system stability and obtain a second mixed solution;

[0119] (35) Vacuum filter the second mixed solution to remove excess ethanol, vacuum dry it at 60 °C for 12 hours, grind and sieve it to obtain an interface enhancer with a particle size ≤ 50 μm.

[0120] (4) Mix hydrophobic silica aerogel, modified layered silicate and interface enhancer into a mixture;

[0121] The hydrophobic silica aerogel, modified layered silicate and interface enhancer are mixed and ground by a ball mill to a mixture with a particle size ≤ 50 μm.

[0122] (5) Add epoxy-organic silicone resin to the mixture.

[0123] Adjust the viscosity of the mixture to 3000 - 8000 mPa·s by adding epoxy-organic silicone resin.

[0124] The specific viscosity needs to be determined according to the actual requirements and will not be elaborated here.

[0125] Example 5

[0126] The difference between this example and Example 4 is as follows:

[0127] In step (31), deionized water is added and the pH is adjusted to 5 with acetic acid.

[0128] In step (32), the mass ratio of silica: silane coupling agent = 3:1;

[0129] In step (33), the first mixture is transferred to a ball mill tank, zirconia ball milling beads with a diameter of 5 mm are added, and the ball-to-material ratio is 5:1; ball milling is carried out for 4 hours at a rotation speed of 600 rpm to ensure that the nano-silica is evenly dispersed and fully bonded with the silane coupling agent;

[0130] In step (34), 1 wt% of propylene oxide is added as a crosslinking agent.

[0131] Example 6

[0132] The difference between this example and Example 4 is as follows:

[0133] In step (31), deionized water is added and the pH is adjusted to 4.5 with acetic acid.

[0134] In step (32), the mass ratio of silica: silane coupling agent = 2:1;

[0135] In step (33), the first mixture is transferred to a ball mill tank, zirconia ball milling beads with a diameter of 4 mm are added, and the ball-to-material ratio is 5:1; ball milling is carried out for 3 hours at a rotation speed of 500 rpm to ensure that the nano-silica is evenly dispersed and fully bonded with the silane coupling agent;

[0136] In step (34), 0.7 wt% of propylene oxide is added as a crosslinking agent.

[0137] Now, products are prepared by the method of Example 4 with different formulation ratios, and the parameters of each product are tested:

[0138] Experimental Example 1

[0139] Use 20 parts of hydrophobic silica aerogel, 40 parts of modified layered silicate, 8 parts of interface enhancer, and 32 parts of epoxy-silicone resin. The ZnO content in the modified layered silicate is 8%, and the tested parameters are as

[0140] shown in Table 1.

[0141]

[0142] Table 1

[0143] Experimental Example 2

[0144] Use 18 parts of hydrophobic silica aerogel, 45 parts of modified layered silicate, 10 parts of interfacial enhancer, and 27 parts of epoxy - silicone resin. The ZnO content in the modified layered silicate is 12%, and a photoinitiator (TPO - L) with a weight of 0.5% of the weight of the epoxy - silicone resin is added to the epoxy - silicone resin to enable ultraviolet - assisted curing. The tested parameters are shown in Table 2.

[0145]

[0146] Table 2

[0147] Experimental Example 3

[0148] Use 15 parts of hydrophobic silica aerogel, 50 parts of modified layered silicate, 5 parts of interfacial enhancer, and 30 parts of epoxy - silicone resin. The ZnO content in the modified layered silicate is 5%, and the tested parameters are as

[0149] shown in Table 3.

[0150]

[0151] Table 3

[0152] Experimental Example 4

[0153] Use 20 parts of hydrophobic silica aerogel, 35 parts of modified layered silicate, 12 parts of interfacial enhancer, and 33 parts of epoxy - silicone resin. The ZnO content in the modified layered silicate is 10%, and the tested parameters are as

[0154] shown in Table 4.

[0155]

[0156] Table 4

[0157] Experimental Example 5

[0158] Use 18 parts of hydrophobic silica aerogel, 42 parts of modified layered silicate, 7 parts of interfacial enhancer, and 33 parts of epoxy - silicone resin. The ZnO content in the modified layered silicate is 9%, and a photoinitiator (TPO - L) with a weight of 0.5% of the weight of the epoxy - silicone resin is added. The tested parameters are shown in Table 5.

[0159]

[0160] Table 5

[0161] It should be noted that all the features disclosed in this specification, or the steps in all the methods or processes disclosed, can be combined in any way except for mutually exclusive features and / or steps.

[0162] In addition, the above specific embodiments are exemplary. Those skilled in the art can come up with various solutions inspired by the disclosure of the present invention, and these solutions also fall within the scope of the disclosure of the present invention and within the protection scope of the present invention. Those skilled in the art should understand that the specification and drawings of the present invention are illustrative and do not constitute a limitation on the claims. The protection scope of the present invention is defined by the claims and their equivalents.

Claims

1. An interface-enhanced aerogel-silicate composite coating, characterized in that, The components include hydrophobic silica aerogel, modified layered silicate, interfacial enhancer and epoxy-organosilicon resin; The weight parts of each component are as follows: Hydrophobic silica aerogel 10-20 parts; Modified layered silicate 30-50 parts; Interfacial enhancer 5-10 parts; Epoxy-organosilicon resin 20-40 parts.

2. An interface-enhanced aerogel-silicate composite coating according to claim 1, characterized in that, The density of the hydrophobic silica aerogel is 0.08 - 0.15 g / cm 3 , and the contact angle ≥ 140°.

3. An interface-enhanced aerogel-silicate composite coating according to claim 2, characterized in that, The modified layered silicate is CTAB intercalated montmorillonite loaded with ZnO, and the loading amount of ZnO is 5-12%.

4. An interface-enhanced aerogel-silicate composite coating according to claim 3 and a preparation method thereof, characterized in that, The interfacial enhancer is a composite system of silane coupling agent and nano-silica, and the silane coupling agent is KH550 or KH560.

5. The preparation method of an interface-enhanced aerogel-silicate composite coating according to any one of claims 1-4, characterized in that, It includes the following steps: (1) Prepare hydrophobic silica aerogel; (2) Prepare modified layered silicate; (3) Prepare interfacial enhancer; (4) Mix hydrophobic silica aerogel, modified layered silicate and interfacial enhancer into a mixture; (5) Add epoxy-organosilicon resin to the mixture.

6. The preparation method of an interface-enhanced aerogel-silicate composite coating according to claim 5, characterized in that, The specific preparation process of the hydrophobic silica aerogel described in step (1) is as follows: (11) Pretreat the aerogel; (11a) Immerse the aerogel in n-hexane and ultrasonically treat for 30 minutes to open pores and remove surface impurities; (11b) Place the aerogel treated in step (11a) in a vacuum drying oven at 60°C and dry for 2 hours to remove residual solvent; (12) Prepare a modified solution; (12a) Dissolve FAS in n-hexane to prepare a 5wt% solution; (12b) Magnetically stir for 30 minutes to ensure uniform mixing to obtain a modified solution; (13) In a vacuum container, immerse the pretreated aerogel in the modified solution, then evacuate to 10 kPa and maintain for 1 hour to promote the penetration of the modified solution into the pores of the aerogel; (14) After releasing the vacuum, let it stand and react in a constant temperature environment at 40°C for 6 hours to allow FAS in the modified solution to fully react with the hydroxyl groups on the surface of the aerogel; (15) Wash the aerogel; (15a) Take out the aerogel, ultrasonically wash it with n-hexane for 10 minutes, and repeat 3 times to remove unreacted FAS; (15b) Then wash it with absolute ethanol 2 times to ensure no residue on the surface; (16) Place the washed aerogel in a vacuum drying oven at 60°C and dry for 12 hours to completely remove the solvent to obtain hydrophobic silica aerogel.

7. The preparation method of an interface-enhanced aerogel-silicate composite coating according to claim 6, characterized in that, The specific preparation process of the modified layered silicate described in step (2) is as follows: (21) Disperse montmorillonite powder in deionized water at a solid-liquid ratio of 1:20, ultrasonically treat for 30 minutes until completely dispersed to obtain a montmorillonite powder solution; (22) Add CTAB to the montmorillonite powder solution at a plasmid ratio of CTAB:montmorillonite = 1:0.5, raise the temperature to 60°C under stirring, and stir and react at 60°C for 6 hours to obtain a first reaction solution; (23) Centrifuge the first reaction solution at 8000 rpm for 10 minutes, discard the supernatant, wash the solid with deionized water until there is no Br- residue, then vacuum dry at 60°C for 12 h, and finally grind it into intercalated montmorillonite with a particle size ≤ 50 μm; (24) Dissolve zinc nitrate in deionized water to form a solution with a concentration of 0.5 M, and add ammonia water to adjust the pH to 9.0 to obtain a zinc nitrate solution. (25) Disperse the intercalated montmorillonite in the zinc nitrate solution at a solid-liquid ratio of 1:10, and stir and react at a temperature of 80 °C for 4 hours to obtain a second reaction solution. (26) Centrifuge the second reaction solution at a speed of 8000 rpm for 10 minutes, then discard the supernatant, wash it 3 times with deionized water and 1 time with ethanol, pre-dry it at a temperature of 60 °C, and finally calcine it at a temperature of 350 °C for 2 hours to form ZnO nanoparticles, thereby obtaining modified layered silicate. The heating rate during the calcination process is 5 °C / min.

8. The preparation method of an interface-enhanced aerogel-silicate composite coating according to claim 7, characterized in that, The preparation process of the interfacial enhancer described in step (3) is as follows: (31) Mix the silane coupling agent and absolute ethanol at a volume ratio of 1:5, add deionized water and adjust the pH to 4-5 with acetic acid, and hydrolyze for 30 min to form a pre-hydrolyzed solution. (32) Add the nano-silica powder to ethanol at a solid-liquid ratio of 1:10, and ultrasonically treat it for 30 min under the condition of a power of 300 W to form a uniformly dispersed solution; add the pre-hydrolyzed solution and continue ultrasonically treating for 1 h to obtain a first mixed solution. Among them, the mass ratio of silica to silane coupling agent is 1:1 - 3:

1. (33) Transfer the first mixed solution to a ball milling tank, add zirconia ball milling beads with a diameter of 3-5 mm, and the ball-to-material ratio is 5:1; ball mill for 2-4 hours at a rotation speed of 400-600 rpm to ensure that the nano-silica is uniformly dispersed and fully bonded with the silane coupling agent. (34) Add 0.5-1 wt% of propylene oxide as a cross-linking agent and stir and react at 60 °C for 1 hour to enhance the system stability and obtain a second mixed solution. (35) Vacuum filter the second mixed solution to remove the excess ethanol, vacuum dry it at 60 °C for 12 hours, and grind and sieve it to obtain an interfacial enhancer with a particle size ≤50 μm.

9. The preparation method of an interface-enhanced aerogel-silicate composite coating according to claim 8, wherein, In step (4), the hydrophobic silica aerogel, the modified layered silicate and the interfacial enhancer are mixed and ground by a ball mill to a mixture with a particle size ≤50 μm.

10. The preparation method of an interface-enhanced aerogel-silicate composite coating according to claim 9, characterized in that, In step (5), the viscosity of the mixture is adjusted to 3000-8000 mPa·s by adding epoxy-organic silicone resin.

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