Aerogel paint with both fire protection and heat insulation, its manufacturing method and its uses

Abstract

We provide aerogel paint that combines fire protection and heat insulation, its manufacturing method and its uses. The present invention includes (1) a mixing and hydrolysis process, (2) a concentration and dispersion process, (3) an atmospheric pressure drying process, (4) a high-temperature-resistant gel mixing process, and (5) a mixing and dispersion process. In this invention, uniformly sized aerogel particles are produced using a suspension, concentration, and dispersion technology. After atmospheric hot air drying, the particles are mixed with a high-temperature-resistant gel material solution to produce an aerogel composite coating that is smokeless, highly fire-resistant, and highly insulating. The product developed in this invention boasts heat resistance of over 1200°C. When sprayed onto aluminum plates, it can prevent the aluminum plate from being burned by the impact of a 1200°C high-temperature flame. It can also be used to safely protect lithium battery modules in electric vehicles from thermal runaway and for high-temperature insulation.

Description

[Technical Field]

[0001] The present invention relates to a high-temperature resistant aerogel fireproof and heat-insulating paint, and more particularly to an aerogel composite paint that is smokeless, has high heat insulation and high fire resistance, and a method for producing the same. [Background technology]

[0002] As is well known, aerogel is a porous material with a three-dimensional network structure, with a porosity exceeding 80% (even exceeding 95%) and a low density (approximately 0.005 to 0.2 g / cm 3 ), high specific surface area (500~2000m 2 Aerogels and their composites possess excellent properties such as high thermal insulation and flame retardancy. These properties make them a valuable tool for future high-temperature fire protection in various industries, energy-intensive production equipment, and transportation pipelines, as well as for energy conservation and carbon emission reduction. Currently, inorganic expandable or aerogel-bonded organic coatings (e.g., epoxy resins, polyamides, polyacrylates, etc.) used in various high-temperature fire-retardant coating patents disclosed internationally are prone to dissolving and fire spread. At temperatures exceeding 600°C, organic coatings using the disclosed conventional technologies gradually carbonize and dissolve, generating toxic gases. Therefore, to protect automotive lithium battery modules from thermal runaway in the future, it is necessary to develop a better fire-retardant coating to replace conventional thermally expandable metal oxide organic fire-retardant coatings. In response to this, the present team aimed to develop aerogel paint that combines high fire and heat resistance, as well as smokeless and non-toxic fire and heat resistance, by applying aerogel-related products to lithium battery modules in electric vehicles to protect against thermal runaway and ensure the safety of next-generation high-temperature fuel cells.

[0003] Traditional aerogel manufacturing methods also use the sol-gel synthesis method, which primarily involves mixing precursors such as methyltrimethoxysilane (MTMS) or methyltriethoxysilane (MTES) with an organic solvent, then adding an acid catalyst to initiate a hydrolysis reaction. An alkali catalyst is then added to initiate a condensation reaction, gradually forming a semi-solid polymer gel. After aging, solvent substitution with organic solvents is performed two or three times, and finally, a dried porous aerogel product is obtained using supercritical or atmospheric high-temperature drying techniques.

[0004] The process technologies used in the above-mentioned aerogel production methods all require large amounts of organic solvents. For example, solvent substitution is performed multiple times over a period of 2-3 days using organic solvents such as alkanes, followed by supercritical drying or atmospheric high-temperature drying. However, the related processes require multiple hydrophobic solvent substitution and supercritical drying steps, which are time-consuming and costly, making them unsuitable for mass production of aerogels and resulting in poor cost-effectiveness.

[0005] In prior patent documents, for example, Patent Document 1 discloses an aerogel water-based intumescent fire-retardant paint in which the emulsion is a mixture of a core-shell type organosilicon-modified acrylic ester emulsion and a pure acrylic emulsion, and a method for preparing the same. The above-mentioned aerogel water-based intumescent fire-retardant paint selects an organosilicon-modified acrylic ester emulsion and a pure acrylic emulsion as the emulsion system.

[0006] Furthermore, for example, Patent Document 2 discloses an aerogel water-based heat insulating fire-resistant paint and a method for producing the same, which comprises (1) a step of modifying an aerogel powder, and (2) a step of mixing, stirring, or ball milling the aerogel powder of the above-mentioned step (1) with the aqueous resin and the flame retardant, and is characterized by being composed of aerogel powder, an aqueous resin, and a flame retardant. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Chinese Patent Application Publication No. 106479297A [Patent Document 2] Chinese Patent Application Publication No. 107267006A Summary of the Invention [Problem to be solved by the invention]

[0008] The above-mentioned prior art technologies all relate to the manufacturing technology of aerogel organic fire-retardant paints or thermally expandable organic fire-retardant paints. These prior art technologies all involve thermally expanding inorganic materials by several to several tens of times at high temperatures, creating a thermally expanded air layer for thermal insulation. The gaps between lithium battery packs in conventional electric vehicles are extremely thin. When using the above-mentioned thermally expandable products, the lithium batteries are subject to high pressure and damage during thermal runaway. Most of these prior art technologies use inorganic thermal expansion materials or aerogel-mixed organic resins, such as epoxy resins, polyamide resins, and water-based polyacrylate resins. However, most of these resins have the disadvantage of having a maximum heat resistance temperature below 200°C. Furthermore, the organic paints used in these prior art technologies gradually deteriorate when exposed to sunlight for long periods of time, reducing their coating effectiveness and causing large amounts of aerogel particles to fall off. Furthermore, in environments above 500°C, the organic paints rapidly deteriorate and dissolve, emitting toxic, dense smoke, making aerogel organic fire-retardant paints unsuitable for high-tech industries.

[0009] The present invention was developed through extensive research by the inventors in light of the above-mentioned problems, and its main objective is to overcome the drawbacks of conventional heat-insulating coatings that use epoxy resins, aqueous polyamide resins, aqueous polymethyl methacrylate mixed aerogels, or thermally expandable metal oxides. The main objective of the present invention is to produce aerogel coatings that combine fire protection and heat insulation by combining an inorganic gel with a suspension aerogel production method, and to provide a silicon-based aerogel coating that combines fire protection and heat insulation and is smokeless, non-toxic, highly flame-retardant, and highly insulating under high-temperature flames.

[0010] Another object of the present invention is to provide a silicon-based aerogel paint that combines fire protection and heat insulation, which has strong adhesive properties to the surface of metal materials, does not deteriorate or dissolve even when exposed to sunlight for long periods of time, and exhibits excellent salt resistance and low moisture absorption even in rainwater or aqueous environments containing trace amounts of salts.

[0011] Yet another object of the present invention is to apply the aerogel fireproof paint to the outer case of the lithium battery module of an electric vehicle or the chassis of the electric vehicle to prevent high temperatures and heat from being rapidly transmitted through the chassis of the electric vehicle due to thermal runaway of the lithium battery module of the electric vehicle and entering the driver's space, thereby providing safety for passengers in the electric vehicle. [Means for solving the problem]

[0012] In this invention, aerogel particles are first produced by suspension dispersion technology. During the production process, the concentrated dispersion solution is stirred at high speed to disperse the silica aerogel molecules, forming wet aerogel particles with diameters of tens of nanometers to tens of micrometers. These are then dried under normal pressure with high-temperature gas to produce aerogel microparticles or nanoparticles with low thermal conductivity and flame retardancy. The dried aerogel particles are then mixed with an inorganic gel material solution. This combination results in an aerogel fire-retardant coating that combines high thermal insulation efficiency, flame retardancy, and is smokeless even under high-temperature flames.

[0013] The method of the present invention can be used to produce aerogel fire-resistant coatings that are smokeless, non-toxic, and have high flame retardancy and heat insulation properties. The method includes a mixing and hydrolysis step (S1) of adding a siloxane precursor to an ethanol aqueous solution and stirring to form a mixed solution, the siloxane precursor comprising a siloxane compound, a hydrophobic siloxane compound substituted with alkyl groups of different chain lengths, or a combination thereof, and then adding an acid catalyst to the mixed solution to cause a hydrolysis reaction. The method also includes a mixing and hydrolysis step (S2) of adding an alkali catalyst solution to the mixed solution and stirring the mixture uniformly to cause a concentration reaction to obtain a concentrated solution. The concentrated solution is then added to the dispersed solution and stirred at high speed using a dispersing device such as an emulsifier or homogenizer to suspend and disperse the concentrated solution in the dispersed solution, resulting in a dispersed solution containing nanometer- to micrometer-sized concentrated oil droplets and dispersed solution formed by the concentration reaction. The dispersed solution is then continuously stirred to form a dispersed solution. The method includes a concentration / dispersion step (S2) of forming nanometer- to micrometer-sized aerogel wet gel particles with stable surfaces; an atmospheric pressure drying step (S3) of filtering the dispersion liquid in which the surface-stabilized aerogel wet gel particles are suspended and dispersed, and then rapidly evaporating the dispersing solvent contained in the surface-stabilized aerogel wet gel particles in a drying tank using an atmospheric pressure high-temperature dry air flow to obtain dry aerogel particles; a high-temperature resistant gel mixing step (S4) of preparing a gel solution that can withstand temperatures above 500°C, adding the dried aerogel particles to the high-temperature resistant gel solution, and stirring at low speed to impregnate and disperse the dried aerogel particles in the high-temperature resistant gel solution; and a mixing / dispersion step (S5) of further mixing and dispersing the high-temperature resistant gel solution impregnated with the dry aerogel particles using a stirring device. In the mixing and dispersion step (S5), a wetting agent, a defoaming agent, and a dispersant are added to the high-temperature resistant gel solution impregnated with the dried aerogel particles, and the aerogel particles are completely and uniformly dispersed in the high-temperature resistant gel solution to form a uniform aerogel paint that combines fire protection and heat insulation. Through these steps, a silicon-based aerogel paint that is smokeless, non-toxic, highly flame-retardant, and highly heat-insulating is obtained under high-temperature flames.

[0014] As described above, the method of the present invention has the following effects. 1. The method of the present invention overcomes the shortcomings of conventional aerogel thermal insulation coatings and thermally expandable organic coatings in terms of high-temperature fire resistance, promoting the widespread application of aerogel thermal insulation materials in high-temperature environments. The present invention produces aerogel fire-retardant coatings that are smokeless, non-toxic, highly flame-retardant, and have excellent thermal insulation properties under high-temperature flames. The aerogel particles are produced using aerogel suspension and dispersion technology, which makes the overall process simple, safe, and economically advantageous. Aerogel particles can also be continuously produced using dynamic drying or high-temperature airflow drying technology in a fluidized bed, improving production efficiency.

[0015] 2. In the method of the present invention, the porosity within the porous aerogel particles, the pore size, the porosity between the aerogel particles, and the compactness of the aerogel structure can be easily adjusted by adjusting the ratio of the siloxane compound and the hydrophobic siloxane compound substituted with alkyl groups of different chain lengths, the content of the hydrolysis solvent, the content of the dispersion solution, the stirring speed of the dispersion equipment such as an emulsifier or homogenizer, and the content and ratio of the acid catalyst and alkali catalyst.

[0016] 3. In the method of the present invention, a technology is provided for rapidly concentrating and dispersing a solution using an emulsifier or homogenizer, and the concentrated dispersion solution is gelled to form aerogel wet gel particles with a stable hydrophobic surface layer in the dispersion solution from the hydrophobic siloxane oil droplets.Furthermore, in the subsequent gelling process, a phase-separated structure is formed inside the aerogel wet gel oil droplets, further forming a porous particulate aerogel structure.

[0017] 4. To address the shortcomings of conventional aerogel organic coatings, the present invention developed a high-temperature-resistant gel solution composed of inorganic gel or organic gel prepared with inorganic gel to prepare aerogel fire-retardant coatings. The prepared high-temperature-resistant gel does not emit any fumes or odors when sprayed with a high-temperature flame of 1200°C, and can form excellent bonds with different materials, including metals, ceramics, plastics, inorganic fibers, and organic fibers. This technology enables the aerogel fire-retardant coating to be used in applications such as isolating and protecting lithium battery modules in electric vehicles from thermal runaway or heat dissipation, as well as for metal panels in fire doors, fire protection and insulation for H-beam structures in buildings, and fire protection and insulation for the interiors of military high-speed aerospace vehicles. The above-mentioned products maintain their effectiveness even in environments of 1200°C.

[0018] Other objects, configurations and effects of the present invention will become apparent from the following detailed description of the preferred embodiments of the present invention. [Brief explanation of the drawings]

[0019] [Figure 1] 1 is a flowchart showing the steps according to a first embodiment of the present invention, illustrating a process for preparing an aerogel flame-retardant paint that is smokeless, non-toxic, highly flame-retardant, and highly insulating under high-temperature flame conditions. [Figure 2] 1 is a photograph showing the appearance of aerogel particles having high heat insulating efficiency and low density, prepared according to the first embodiment of the present invention. [Figure 3] 1 is a scanning electron microscope (SEM) photograph of aerogel particles having high thermal insulation efficiency and low density prepared according to the first embodiment of the present invention, at a magnification of 10,000 times. [Figure 4] 1 is a photograph showing the appearance of aerogel flame-retardant paint prepared according to the first embodiment of the present invention, which is smokeless, non-toxic, and has high flame retardancy and high heat insulation properties under high-temperature flame conditions. [Figure 5]1 is a scanning electron microscope (SEM) photograph of a cross section of an aerogel flame-retardant coating prepared according to the first embodiment of the present invention, which is smokeless, non-toxic, and has high flame retardancy and heat insulation properties under high-temperature flame conditions, at a magnification of 5000x. [Figure 6] These are photographs showing the appearance of a typical 1mm thick aluminum plate before and after it has been sprayed with a high-temperature flame at 1200°C. [Figure 7] 1 is a photograph showing the appearance of an aluminum plate sprayed with a smokeless, non-toxic aerogel flame-retardant paint prepared in accordance with the first embodiment of the present invention, which has high flame retardancy and heat insulation properties under high-temperature flame conditions, before and after spraying with a high-temperature flame at 1200°C. DETAILED DESCRIPTION OF THE INVENTION

[0020] The present invention will be described below through embodiments of the invention, but the following embodiments do not limit the scope of the invention according to the claims. Furthermore, not all of the combinations of features described in the embodiments are necessarily essential to the solution of the invention.

[0021] Figure 1 shows a first embodiment of the method for producing an aerogel fire-retardant paint according to the present invention. This method is formed by adding aerogel to either an inorganic gel solution or an inorganic / organic gel solution, and the aerogel fire-retardant paint is smokeless, non-toxic, highly flame-retardant, and highly insulating under high-temperature flames. The process includes a mixing and hydrolysis step (S1), a concentration and dispersion step (S2), an atmospheric drying step (S3), a high-temperature-resistant gel mixing step (S4), and a mixing and dispersion step (S5). Each step is described below.

[0022] In the mixing and hydrolysis step (S1), a siloxane precursor is added to an aqueous ethanol solution to form a mixed solution. The siloxane precursor includes a hydrophobic-modified siloxane compound, a siloxane compound, or a combination thereof. An acid catalyst is then added to the mixed solution to cause a hydrolysis reaction. In some embodiments, the siloxane compound includes tetramethoxysilane (TMOS), tetraethoxysilane (TEOS), or any combination thereof. In some embodiments, the hydrophobically modified siloxane compound includes a hydrophobic siloxane compound substituted with an alkyl group having a different chain length, such as methyltrimethoxysilane (MTMS), propyltrimethoxysilane (PTMS), hexyltrimethoxysilane (HTMS), octyltrimethoxysilane (OTMS), or hexamethyldisilane (HMDS), or any combination thereof. Specifically, the total molar content of the siloxane compound and the hydrophobic siloxane compound substituted with an alkyl group having a different chain length ranges from 0.5 mol% to 40 mol%, and the molar ratio of the content of the ethanol aqueous solution ranges from 99.5 mol% to 60 mol%.

[0023] In this example, the molar ratio of the siloxane compound and the hydrophobic siloxane compound substituted with alkyl groups of different chain lengths ranges from (0:100) to (95:5.0). In some preferred embodiments, the molar ratio of the siloxane compound and the hydrophobic siloxane compound substituted with alkyl groups of different chain lengths is 5:95. In the aqueous ethanol solution, the molar ratio of ethanol to water ranges from 0:100 to 50:50. In some preferred embodiments, the molar ratio of ethanol to water is 15:85.

[0024] In the mixing and hydrolysis step (S1), a large amount of aqueous ethanol solution containing a siloxane compound, a hydrophobic siloxane compound substituted with alkyl groups of different chain lengths, and a trace amount of acid catalyst is thoroughly mixed. During the mixing process, a hydrolysis reaction simultaneously occurs. The aqueous ethanol solution containing a trace amount of acid catalyst comprises ethanol, deionized water, treated water, secondary treated water, or a mixture of any of these components. The molar ratio of the total content of the mixture of the siloxane compound and the hydrophobic siloxane compound substituted with alkyl groups of different chain lengths to the content of the acid catalyst is in the range of 1:0.01 to 1:0.0005. The higher the content ratio of the acid catalyst in the mixed solution, the faster the hydrolysis rate. In some preferred embodiments, the molar ratio of the total content of the mixture of the siloxane compound and the hydrophobic siloxane compound substituted with alkyl groups of different chain lengths to the content of the acid catalyst is 1:0.0015.

[0025] Next, in the concentration / dispersion step (S2), an alkali catalyst solution is added to the mixed solution and uniformly stirred to induce a concentration reaction. The dispersion solution is then added to the concentrated solution, and high-speed stirring and dispersion is performed using a dispersing device such as an emulsifier or homogenizer to suspend and disperse the concentrated solution in the dispersion solution. The concentrated solution is then continuously stirred and suspended to form concentrated sol oil droplets of nanometer to micrometer size. The concentrated oil droplets gel to form surface-stable aerogel wet gel particles, which are then suspended and dispersed in the dispersion solution. The volume ratio of the dispersion solution to the ethanol aqueous solution is between 50:10 and 30:70. In some preferred embodiments, the volume ratio of the dispersion solution to the ethanol aqueous solution is 50:20.

[0026] In the concentration / dispersion step, increasing the temperature significantly shortens the concentration / reaction time. That is, in the concentration / dispersion step (S2), the gelation time of the aerogel is effectively shortened. When the equivalent ratio of the alkali catalyst to the acid catalyst is 1.0:1.0, the concentration / reaction temperature is in the range of 20 to 55°C, and the concentration / reaction time is in the range of 20 to 250 minutes. In some preferred embodiments, the concentration / reaction temperature is 40°C, and the concentration / reaction time is approximately 50 minutes. When the concentration / reaction temperature is 50°C, the concentration / reaction time is approximately 25 minutes.

[0027] In the concentration and dispersion process, the nanometer- to submicrometer-sized aerogel wet gel particles contain a large amount of hydrophobic siloxane compounds substituted with alkyl groups of different chain lengths. The size of the initial structures formed by the mixture of the siloxane compound and the hydrophobically modified siloxane compound in the aqueous dispersion is controlled to be in the range of 5 to 10 nm, and these initial structures are re-deposited to form aerogel wet gel particles in the range of 50 to 300 nm. In this way, the nanometer- to submicrometer-sized aerogel wet gel particles form stable suspension particles in the aqueous dispersion system during the concentration and dispersion process. The volume ratio of the mixture of the siloxane compound and the hydrophobic siloxane compound to the aqueous dispersion is between (1.0:1.0) and (1.0:5.0). In some embodiments, the volume ratio is 1.0:1.0, and the concentration and reaction time is 70 minutes. Preferably, the volume ratio is 1.0:3.0, and the concentration and reaction time is 30 minutes. More preferably, the volume ratio is 1.0:1.5, the concentration reaction time is shortened to 55 minutes, and the yield of aerogel particles is high.

[0028] In some embodiments, increasing the content of the alkali catalyst also significantly shortens the concentration reaction time. The equivalent ratio of the contents of 1.0 M alkali catalyst to 1.0 M acid catalyst is in the range of (0.8:1.0) to (2.0:1.0), and the concentration reaction time is in the range of 360 to 3 minutes. Preferably, the equivalent ratio of the contents is 1.2:1.0, and the concentration reaction time is 40 minutes. More preferably, the equivalent ratio of the contents is 1.6:1.0, and the concentration reaction time is about 10 minutes. In some preferred embodiments, the volume ratio of the contents is 1.2:1.0.

[0029] Furthermore, the atmospheric drying step (S3) includes a solvent evaporation step (S3-1), a solvent recovery step (S3-2), and a solvent bumping step (S3-3).

[0030] In the solvent evaporation step (S3-1), the dispersion solution system containing the surface-stabilized aerogel wet gel particles is filtered to remove the dispersion solution, and then a high-temperature dry air stream at atmospheric pressure is applied to a drying tank to rapidly evaporate the water and alcohol solvent remaining in the sub-micrometer aerogel wet gel particles. In this manner, dry aerogel particles with a porous structure, low thermal conductivity, and high fire resistance are rapidly obtained using the high-temperature dry air stream drying technique at atmospheric pressure. The rapid azeotropic vaporization temperature of the large amount of mixed solvent present in the aerogel wet gel particles is between 60 and 90°C. Preferably, the azeotropic vaporization temperature is 90°C.

[0031] In the atmospheric pressure drying process (S3), a solvent recovery facility is further designed to perform the solvent recovery process (S3-2). In the atmospheric pressure high temperature air flow drying process, the evaporated vapor is guided to the heat exchange recovery facility in an azeotropic vaporization temperature environment, thereby reducing costs and environmental pollution.

[0032] Next, in the solvent bumping step (S3-3), most of the solvent in the wet aerogel particles is vaporized to obtain a dry aerogel structure. The temperature of the dry airflow from the dry aerogel structure is adjusted to a temperature above the bumping temperature of the mixed solvent. Combined with microwave frequencies, this breaks the hydrogen bonds of the water molecules in the aerogel structure, causing rapid bumping of the excess mixed solvent within the dry aerogel structure, forming positive-pressure vapor. During the expansion of the dry aerogel structure, a large number of nanometer- to submicrometer-scale micropores are generated, improving the porosity and insulating properties of the dry aerogel particles and the end-end product. Preferably, the bumping temperature is in the range of 110-180°C, more preferably in the range of 150-180°C.

[0033] Next, in the high-temperature-resistant gel mixing step (S4), a high-temperature-resistant gel solution capable of withstanding temperatures above 500°C is prepared. The dried aerogel particles are added to the high-temperature-resistant gel solution under low-speed stirring using a stirrer. The dry aerogel particles are impregnated and dispersed in the gel solution capable of withstanding temperatures above 500°C under low-speed stirring. This includes pure inorganic gels or those made by mixing a trace amount of organic gel material with an inorganic gel material. Examples of the inorganic gel material mixed with a trace amount of organic gel include a mixture of 75 to 97 v / v% inorganic gel material and 3 to 25 v / v% organic hot gel material. Examples of inorganic gel materials include sodium silicate, inorganic silicon resin, silicate gel, inorganic silicon polymer gel, phosphate-silicate gel, magnesium oxide-silicon dioxide-borax inorganic gel, or any combination thereof. The organic gel material may be one of polyimide, polyetherimide, polytetrafluoroethylene, high-temperature resistant silica gel, organosilicon-modified polyurethane, organosilicon-modified polyacrylic acid, organosilicon-modified acrylic ester, organosilicon-modified polyvinyl alcohol, organic high-temperature resistant silicone resin, and organosilicon-modified epoxy resin, or any combination thereof. The weight content of the dry aerogel particles in the entire aerogel fire-retardant coating is between 10.0 and 45.0 wt%, and the weight content of the high-temperature resistant gel solution is between 55.0 and 90 wt%. Therefore, to optimally prepare an aerogel fire-retardant coating that exhibits smokelessness, high thermal insulation efficiency, and flame retardancy under high-temperature flames, the weight content of the dry aerogel particles is preferably between 13.0 and 15.0 wt%.

[0034] Next, in the mixing and dispersing step (S5), the high-temperature resistant gel solution impregnated with the dried aerogel particles is further mixed and dispersed using a stirrer to obtain a silicon-based aerogel paint that is smokeless, non-toxic, highly flame-retardant, and highly insulating. The object of the present invention is to overcome the shortcomings of conventional aerogel organic paints or thermally expandable metal oxide organic fire-retardant paints and to produce an aerogel inorganic fire-retardant paint that has excellent adhesion to metal or plastic plates and is smokeless, non-toxic, highly flame-retardant, and highly insulating under high-temperature flames.

[0035] The following examples are presented in conjunction with the accompanying drawings. Figure 2 is a photograph of the appearance of aerogel particles prepared according to the first example of the present invention, which have high insulating efficiency and low density. The aerogel particles shown in the photograph are a highly uniform white powder.

[0036] Figure 3 shows a scanning electron microscope (SEM) photograph of aerogel particles with high thermal insulation efficiency and low density prepared according to the first embodiment of the present invention, magnified 10,000 times. Observation under the electron microscope clearly reveals the microstructure of spherical aerogel particles. The particle size of the spherical aerogel particles ranges from approximately 100 to 200 nm, and the aggregate size of the aerogel particles ranges from approximately submicrometers to tens of micrometers.

[0037] Figure 4 is a photograph showing the appearance of an aerogel fire-retardant paint prepared according to a first embodiment of the present invention, which is smokeless, non-toxic, highly flame-retardant, and highly insulating under high-temperature flame conditions. Specifically, the aerogel fire-retardant paint produced has a white, viscous appearance, and the color of the aerogel fire-retardant paint can be adjusted to black or other colors using inorganic pigments. The aerogel fire-retardant paint contains aerogel particles ranging from submicrometers to tens of micrometers, providing high-temperature resistance and excellent insulating properties. The above-mentioned combination results in a smokeless, non-toxic aerogel fire-retardant paint that is highly flame-retardant and highly insulating under high-temperature flame conditions, thereby expanding the range of applications for aerogel.

[0038] Figure 5 is a scanning electron microscope (SEM) photograph (magnification: 5000x) of the cross section of an aerogel fire-retardant coating prepared according to a first embodiment of the present invention, which is smokeless, non-toxic, and exhibits high flame retardancy and thermal insulation properties under high-temperature flame conditions. As shown in Figure 5, the interior of this aerogel fire-retardant coating contains a composite of sub-micrometer to 10-micrometer aerogel aggregates coated with a high-temperature-resistant gel. Specifically, a large number of sub-micrometer aerogel molecular aggregates are dispersed throughout the high-temperature-resistant gel. Furthermore, the cross section of the aerogel fire-retardant coating clearly shows that the aerogel molecular aggregates still contain a large number of pores. Therefore, the large amount of aerogel and pores throughout the cross-sectional structure of the aerogel fire-retardant coating provide the aerogel fire-retardant coating with low thermal conductivity and high thermal insulation properties.

[0039] Figure 6 shows photographs of the appearance of a typical 1mm thick aluminum plate before and after it has been sprayed with a high-temperature flame at 1200°C. During the process of spraying with a high-temperature flame at 1200°C, the temperature of the back of the aluminum plate reaches approximately 600°C in 50 seconds, and when sprayed with a high-temperature flame at 1200°C, the aluminum plate is burned out in approximately 1 minute, as shown on the right side of Figure 6.

[0040] Figure 7 shows photographs of an aluminum plate sprayed with an aerogel fire-retardant paint prepared according to the first embodiment of the present invention, which is smokeless, non-toxic, and highly flame-retardant and insulating under high-temperature flame conditions. The photographs show the appearance of the aluminum plate before and after spraying with a 1200°C high-temperature flame. Specifically, the aerogel fire-retardant paint is sprayed to a thickness of approximately 150 μm. The rear surface temperature of the aluminum plate during spraying with a high-temperature flame is approximately 350°C. Even after spraying with a 1200°C high-temperature flame for three hours, no burnout occurred, as shown on the right side of Figure 7. This demonstrates that the aerogel fire-retardant paint exhibits excellent fire and thermal insulation properties under high-temperature flame conditions, making it suitable for use in preventing thermal runaway in lithium battery modules for electric vehicles.

[0041] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention. [Explanation of symbols]

[0042] (S1) Mixed hydrolysis process (S2) Concentration and dispersion process (S3) Normal pressure drying process (S4) High temperature resistant gel mixing process (S5) Mixing and dispersion process (S3-1) Solvent evaporation process (S3-2) Solvent recovery process (S3-3) Solvent bumping process

Claims

1. A method for producing an aerogel paint that has both fire protection and heat insulation properties, which is formed by adding an inorganic gel / organic gel solution to silica aerogel, a mixing and hydrolysis step of adding a siloxane precursor to an ethanol aqueous solution to form a mixed solution, the siloxane precursor including a hydrophobically modified siloxane compound and a siloxane compound, and then adding an acid catalyst to the mixed solution to cause a hydrolysis reaction; a concentration-dispersion process in which an alkali catalyst solution is added to the mixed solution to cause a concentration reaction to obtain a concentrated solution, a dispersion solution is added to the concentrated solution, and the mixture is stirred at high speed using an emulsifier or homogenizer to form sol oil droplets from the mixed siloxane compound in the concentrated solution, which are then suspended and dispersed in the dispersion solution, and the sol oil droplets are concentrated to form wet gel particles of aerogel, which have a stable hydrophobic shell layer and are uniformly dispersed in the dispersion solution; a drying step of filtering the dispersion solution through a filter at atmospheric pressure and a drying temperature to obtain wet gel particles of the aerogel, and then providing a high-temperature dry air stream at atmospheric pressure to rapidly evaporate the solvent contained in the wet gel particles of the aerogel to obtain dry aerogel particles, the drying temperature being in the range of 60 to 150°C; a high-temperature-resistant gel mixing process comprising preparing a high-temperature-resistant gel solution, stirring the high-temperature-resistant gel solution at a low speed, adding the dry aerogel particles to the high-temperature-resistant gel solution, and impregnating and dispersing the dry aerogel particles in the high-temperature-resistant gel solution during low-speed stirring; the high-temperature-resistant gel solution is resistant to a high temperature of at least 500°C; and the weight content % of the dry aerogel particles is in the range of 10.0 to 45.0 wt% and the weight content % of the high-temperature-resistant gel solution is in the range of 55.0 to 90 wt%, with respect to the entire aerogel coating having both fire protection and heat insulation properties; and the inorganic gel material comprises sodium silicate, inorganic silicon resin, silicate gel, inorganic silicon polymer gel, phosphate-silicate gel, magnesium oxide-silicon dioxide-borax inorganic gel, or any combination thereof; The organic gel material is a high-temperature resistant gel mixed step, which includes a group consisting of polyimide, polyetherimide, polytetrafluoroethylene, high-temperature resistant silica gel, organosilicon-modified polyurethane, organosilicon-modified polyacrylic acid, organosilicon-modified acrylic acid ester, organosilicon-modified polyvinyl alcohol, organic high-temperature resistant silicone resin, and organosilicon-modified epoxy resin, or any combination thereof; a mixing and dispersing step of mixing and dispersing the high-temperature resistant gel solution impregnated with the dry aerogel particles by a stirrer, and at the same time adding a wetting agent, a defoaming agent, and a dispersant to the high-temperature resistant gel solution impregnated with the dry aerogel particles to completely and uniformly disperse the dry aerogel particles in the high-temperature resistant gel solution, thereby forming an aerogel paint that is smokeless, non-toxic, and has fire protection and heat insulation properties even under fire.

2. The atmospheric drying step a solvent evaporation step of performing rapid azeotropic evaporation of the solvent in the wet gel particle structure of the aerogel at an azeotropic evaporation temperature, the azeotropic evaporation temperature being in the range of 60 to 90°C; a solvent recovery step of guiding the azeotropic solvent vapor to a heat exchange recovery system to condense and recover the solvent; and a solvent bumping step in which the drying temperature is adjusted to a bumping temperature, and the solvent and water molecules contained in the dried aerogel structure are bumped at high speed while generating positive pressure steam, thereby suppressing drying shrinkage of the aerogel structure and the formation of a large number of micropores, and achieving a high thermal insulation effect, wherein the bumping temperature is in the range of 110 to 180°C.

3. The siloxane compounds include tetramethoxysilane (TMOS), tetraethoxysilane (Tetraethoxysilane), the hydrophobically modified siloxane compound comprises methyltrimethoxysilane (MTMS), propyltrimethoxysilane (PTMS), hexyltrimethoxysilane (HTMS), octyltrimethoxysilane (OTMS), hexamethyldisilane (HMDS), or any combination thereof; and the siloxane precursor has a molar ratio of the siloxane compound to the hydrophobically modified siloxane compound ranging from 0:100 mol% to 95:5.0 mol%.

2. The method for producing an aerogel coating having both fire protection and heat insulation according to claim 1, wherein the aerogel coating has a flame retardant and heat insulating property in a range of 0.05 to 0.05% by mass.

4. 2. The method for producing an aerogel paint having both fire protection and heat insulation properties according to claim 1, wherein the mixing and dispersing step includes dispersing the dry aerogel particles impregnated in the high-temperature resistant gel solution using a stirring and dispersing device.

5. The method for producing aerogel paint with both fireproof and heat-insulating properties according to claim 1, characterized in that the weight content % of the dry aerogel particles is in the range of 13.0 to 15.0 wt%.

6. The dry aerogel particles contained in the fireproof and heat-insulating aerogel coating have a porous structure, with a porosity ranging from 50.0 to 75.0% and a density ranging from 0.06 to 0.12 g / cm ３ its thermal conductivity coefficient is in the range of 0.020 to 0.045 W / mk, its relative dielectric constant is in the range of 1.30 to 1.85, and its heat resistance performance is UL94-V0 or higher; The method for producing an aerogel paint having both fire protection and heat insulation as described in claim 1, characterized in that the aerogel paint having both fire protection and heat insulation is further combined with a highly heat-resistant inorganic gel or an inorganic-organic mixed gel material to form a highly heat-insulating and highly fire-resistant aerogel inorganic fireproof paint, and when the highly heat-insulating and highly fire-resistant aerogel inorganic fireproof paint is sprayed onto the front surface of an aluminum plate to a thickness of 150 μm, even after drying and being thermally sprayed with a high-temperature flame at 1200°C for 3 hours, the temperature of the back surface of the aluminum plate relative to the front surface is in the range of 300 to 350°C, and the aluminum plate does not burn through.

7. 7. A fire-resistant and heat-insulating aerogel paint for applications such as protecting lithium battery modules in electric vehicles from thermal runaway, providing fire protection and heat insulation for metal panels in fire doors, H-shaped steel structures for architecture, and the interiors of high-speed military aerospace vehicles, thereby preventing the above-mentioned products from losing their functionality even in an environment of 1200 degrees Celsius, and characterized in that the fire-resistant and heat-insulating aerogel paint is manufactured by the manufacturing method of any one of claims 1 to 6.

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