Inorganic thermal insulation coating and preparation method thereof

Abstract

The present invention relates to the technical field of inorganic thermal insulation coatings, and in particular to an inorganic thermal insulation coating and a preparation method thereof, which overcomes the shortcomings of the prior art and comprises the following components: 30-50 parts of modified silicate, 10-20 parts of hollow microspheres, 5-15 parts of phase change material, 5-15 parts of polymer monomer, 1-5 parts of nano-carbon fiber, 3-8 parts of metal oxide nanowires, 5-10 parts of nano-alumina powder, 2-6 parts of aerogel, 3-8 parts of flame retardant, 5-15 parts of gelling material, and 1-5 parts of stabilizer. By carefully selecting and combining various functional components, such as modified silicate, hollow microspheres, phase change material, nano-carbon fiber, metal oxide nanowire, nano-alumina powder, aerogel, etc., an inorganic thermal insulation coating is prepared. The coating not only has a low thermal conductivity and excellent non-flammability, but can also be used in combination with a variety of primers and topcoats to form a complete anti-corrosion, thermal insulation, and decorative system.

Description

Technical Field

[0001] The present invention relates to the technical field of inorganic thermal insulation coatings, and in particular to an inorganic thermal insulation coating and a preparation method thereof. Background Art

[0002] With the global energy crisis and environmental pollution becoming increasingly prominent, energy conservation, emission reduction, and green buildings have become key priorities for social development. In the construction, industrial, and other fields, the use of thermal insulation materials plays a key role in improving energy efficiency and reducing energy consumption. While traditional organic and inorganic thermal insulation coatings can meet insulation needs to a certain extent, they each have significant shortcomings.

[0003] Organic insulation coatings, such as polystyrene foam boards, offer excellent insulation, but they suffer from poor fire resistance and flammability, posing safety risks. On the other hand, inorganic insulation coatings, such as rock wool and glass wool, while fire-resistant, offer relatively poor insulation performance. Furthermore, the coatings are thick, resulting in seams that can easily peel, poor adhesion, and poor water resistance. These shortcomings limit the application of traditional insulation coatings in energy-efficient buildings and complex industrial environments.

[0004] Deficiencies in the existing technology:

[0005] The contradiction between thermal insulation performance and safety: Traditional organic thermal insulation coatings have good thermal insulation effects but poor safety, while inorganic thermal insulation coatings are the opposite, and it is difficult to take both into account.

[0006] Difficulty in construction: The coating after construction of inorganic coatings is often thicker, with joints and easy to fall off, which not only affects the thermal insulation effect, but also brings difficulties to construction.

[0007] Insufficient water resistance and adhesion: Traditional inorganic thermal insulation coatings perform poorly in water resistance and adhesion, limiting their scope of application.

[0008] Therefore, we propose an inorganic thermal insulation coating and a preparation method thereof to solve the above problems. Summary of the Invention

[0009] The purpose of the present invention is to solve the shortcomings of the prior art and to propose an inorganic thermal insulation coating and a preparation method thereof.

[0010] In order to achieve the above object, the present invention adopts the following technical solutions:

[0011] An inorganic thermal insulation coating comprises the following components in parts by weight: 30-50 parts of modified silicate, 10-20 parts of hollow microspheres, 5-15 parts of phase change material, 5-15 parts of polymer monomer, 1-5 parts of nano-carbon fiber, 3-8 parts of metal oxide nanowires, 5-10 parts of nano-alumina powder, 2-6 parts of aerogel, 3-8 parts of flame retardant, 5-15 parts of gelling material and 1-5 parts of stabilizer.

[0012] As the preferred technical solution:

[0013] The inorganic thermal insulation coating as described above includes the following components in parts by weight: 40 parts of modified silicate, 14 parts of hollow microspheres, 7 parts of phase change material, 8 parts of polymer monomer, 3 parts of nano-carbon fiber, 4 parts of metal oxide nanowires, 7 parts of nano-alumina powder, 4 parts of aerogel, 5 parts of flame retardant, 11 parts of gelling material, and 3 parts of stabilizer.

[0014] As described above, the inorganic thermal insulation coating, the hollow microspheres are one of glass hollow microspheres and ceramic hollow microspheres, the phase change material is one of paraffin and fatty acid phase change materials, the metal oxide nanowires are one of aluminum oxide metal oxide nanowires and zinc oxide metal oxide nanowires, the aerogel is silica aerogel, the flame retardant is a phosphorus-based or nitrogen-based flame retardant, the gelling material is an inorganic polymer gelling material, and the polymer monomer is one of methyl methacrylate, styrene, and acrylate.

[0015] The inorganic thermal insulation coating as described above has the following features: the particle size of the modified silicate is in the range of 1 to 100 microns, the particle size of the hollow microspheres is in the range of 10 to 150 microns, the wall thickness of the hollow microspheres is 1 to 5 microns, the phase change temperature of the phase change material is in the range of 20 to 30°C, the diameter of the nano-carbon fibers is controlled to be in the range of 10 to 100 nanometers, and the length is in the range of 1 to 10 microns, the diameter of the metal oxide nanowires is in the range of 10 to 50 nanometers, and the length is in the range of 0.1 to 1 micron, the particle size of the nano-alumina powder is in the range of 10 to 100 nanometers, and the specific surface area is in the range of 100 to 500 m 2 / g, the pore size of the aerogel is 10-100 nanometers, the porosity is greater than 90%, and the density of the aerogel is controlled at 0.1-0.3g / cm 3 The viscosity of the gelling material is 1000 to 5000 mPa·s.

[0016] In the inorganic thermal insulation coating as described above, the carbon nanofibers and the metal oxide nanowires construct a continuous network structure or a three-dimensional heat-conducting network skeleton in the coating to obtain a heat-conducting network. Heat-conducting nodes are provided in the heat-conducting network. These heat-conducting nodes are composed of high thermal conductivity materials. The heat-conducting network works in conjunction with the phase change material. The heat-conducting network can disperse the heat stored or released by the phase change material into the entire coating layer. The temperature of the coating layer is set to T(x, t), where x is the spatial coordinate and t is the time. Then:

[0017]

[0018] Where α is the thermal diffusivity, expressed as:

[0019]

[0020] Where ρ is the density of the coating, C p is the specific heat capacity of the coating, It is the rate of change of temperature T with time t, which indicates the rate of change of temperature with time at a certain point; It is the second-order partial derivative of temperature T with respect to the spatial coordinate x, which represents the rate of change of temperature with space, that is, the curvature of the temperature curve;

[0021] The phase change material is encapsulated by microcapsule technology, and a microcapsule with a multi-layer encapsulation structure is designed, wherein the inner layer encapsulates the phase change material, and the shell layer is made of thermal resistance material and / or the shell layer has a porous structure.

[0022] A second aspect of the present invention provides a method for preparing an inorganic thermal insulation coating, comprising the following steps:

[0023] S1: Using an ultrasonic reactor to carry out a modification reaction, the base silicate raw material is mixed with the modifier, and stirred for reaction. After the reaction is completed, the modified silicate powder is obtained by filtering, washing and drying for use;

[0024] S2: The hollow microspheres are dispersed in anhydrous ethanol, and a silane coupling agent is added for surface grafting. After stirring and reacting at room temperature for several hours, the hollow microspheres are dispersed in nano-silica sol for secondary coating, and then dried;

[0025] S3: The phase change material and polymer monomer mixture is sprayed into hot air through an electrospray device, and dried instantly to form microcapsules. After the reaction is completed, the phase change microcapsules are obtained by centrifugation, washing, and drying;

[0026] S4: Mix the modified silicate powder, gelling material, stabilizer and a small amount of water, and stir at medium speed in a high-speed disperser to form a uniform base slurry;

[0027] S5: adding nano-carbon fibers, metal oxide nanowires, nano-alumina powder and aerogel to the base slurry in sequence and performing ultrasonic dispersion, increasing the stirring speed after each addition;

[0028] S6: After ensuring that the nano-components are fully dispersed, slowly add the phase change microcapsules and the surface treated hollow microbeads, reduce the stirring speed to low speed, and continue stirring to ensure that the microcapsules and hollow microbeads are evenly distributed in the slurry without destroying its structure;

[0029] S7: Finally, flame retardant compounding technology is used to compound multiple flame retardants, and the compounded flame retardants are added to the mixed slurry. Stirring is carried out to ensure that the flame retardants are evenly dispersed and fully mixed with other components to obtain an inorganic thermal insulation coating.

[0030] As the preferred technical solution:

[0031] As described above, a method for preparing an inorganic thermal insulation coating, in said S1, an ultrasonic reactor is used to carry out a modification reaction, a basic silicate raw material is mixed with a modifier, and the mixture is stirred and reacted at 60 to 80° C., and ultrasonic stirring reaction is carried out at a frequency of 40 kHz for 4 to 6 hours. After the reaction is completed, the mixture is filtered, washed with deionized water for 3 to 5 times, and then dried at 80° C. for 4 hours to obtain a modified silicate powder for standby use.

[0032] As described above, a method for preparing an inorganic thermal insulation coating, in said S3, a mixed liquid of phase change material and polymer monomer is sprayed into hot air through an electrospray device at a spray rate of 5 mL / min, and the hot air is 150°C, and is instantly dried to form microcapsules. After the reaction is completed, it is centrifuged at a speed of 3000-4000 rpm for 7-10 minutes, washed with ethanol 3-5 times, and then dried at 40-50°C for 6-9 hours to obtain phase change microcapsules.

[0033] As described above, a method for preparing an inorganic thermal insulation coating comprises subjecting hollow microbeads to magnetic or conductive treatment, wherein the surfaces of the hollow microbeads are treated so as to be linearly arranged in the coating, and an external magnetic field or electric field is used to guide the hollow microbeads to be linearly arranged in the coating, so that the hollow microbeads move in a directed manner in the coating and are arranged in an orderly manner, forming an ordered thermal insulation layer. The hollow microbeads are composed of a plurality of small molecule clusters, which are connected by weak interaction forces, thereby maintaining the stability of the microbead structure while improving the thermal insulation performance.

[0034] The preparation method of the inorganic thermal insulation coating as described above further includes S8: adding a thickener or a pH regulator to adjust the viscosity and pH value, allowing the evenly mixed coating to stand for 2 to 4 hours to eliminate bubbles generated during the stirring process, and then drying naturally at room temperature.

[0035] Compared to existing technologies, the present invention comprises a mixture of modified silicate, hollow microspheres, phase change material, polymer monomer, carbon nanofibers, metal oxide nanowires, nanoalumina powder, aerogel, flame retardant, gelling material, and stabilizer, all mixed in a specific ratio. The carbon nanofibers and metal oxide nanowires form a thermally conductive network within the coating, synergizing with the phase change material to disperse heat. Through a specific preparation method, including ultrasonic modification, surface grafting, and microencapsulation, a high-performance inorganic thermal insulation coating is achieved.

[0036] Beneficial effects benefits:

[0037] Excellent thermal insulation performance: By carefully selecting and combining various high-performance materials, such as nano-carbon fibers, metal oxide nanowires, aerogels, etc., a thermal conductive network is formed to effectively prevent heat transfer and provide excellent thermal insulation effect.

[0038] Enhanced safety: The use of inorganic materials as the main body, combined with the use of flame retardants, makes the coating have excellent non-flammability, greatly improving the safety of use.

[0039] Good construction performance: The various components of the coating are finely processed and dispersed to form a uniform and easy-to-construct slurry, which reduces coating joints, prevents falling off, and facilitates construction on various complex surfaces.

[0040] Strong water resistance and adhesion: Through specific preparation technology and selection of appropriate stabilizers, the water resistance of the coating and its adhesion to various substrates are improved, thus extending the service life of the coating.

[0041] Multiple components synergistically enhance thermal insulation performance: modified silicates, hollow microspheres, aerogels and other components in the coating have low thermal conductivity and good thermal insulation performance. They work synergistically to effectively reduce heat transfer and provide excellent thermal insulation effect; nano-carbon fibers and metal oxide nanowires form a continuous thermal conductive network in the coating. The high thermal conductivity of these nanomaterials can quickly disperse the heat stored or released by the phase change material into the entire coating layer; the phase change material is encapsulated through microencapsulation technology and can absorb or release heat when the temperature changes, thereby slowing down the fluctuation of ambient temperature. This dynamic temperature regulation ability works synergistically with the thermal conductive network of the nanomaterial to enhance the thermal stability and energy-saving effect of the coating.

[0042] In summary, this inorganic thermal insulation coating has shown significant advantages in thermal insulation performance, temperature control, safety, construction and adhesion through the synergistic effect of different components. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 A line graph showing data of detection category 1 of the embodiments and comparative examples of the present invention;

[0044] Figure 2 It is a line graph of data of detection category 2 of the embodiments and comparative examples of the present invention;

[0045] Figure 3 It is a line graph of data of detection category 4 of the embodiments and comparative examples of the present invention. DETAILED DESCRIPTION

[0046] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. In the event of a conflict, the definitions in this specification will prevail. “When mass, concentration, temperature, time, or other values ​​or parameters are expressed as a range, a preferred range, or a range defined by a series of upper preferred values ​​and lower preferred values, this should be understood to specifically disclose all ranges formed by any pairing of any upper range limit or preferred value with any lower range limit or preferred value, regardless of whether the range is disclosed alone. For example, a range of 1-50 should be understood to include the range selected from 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91 6, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50, any number, combination of numbers, or subrange, and all decimal values ​​between the aforementioned integers, for example, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, and 1.9. With respect to subranges, "nested subranges" extending from any endpoint within the range are specifically contemplated. For example, nested subranges of the exemplary range 1-50 may include 1-10, 1-20, 1-30, and 1-40 in one direction, or 50-40, 50-30, 50-20, and 50-10 in the other direction.

[0047] The present invention will be further explained below with reference to specific examples. The experimental methods described in the following examples are conventional methods unless otherwise specified; the reagents and materials described are commercially available unless otherwise specified.

[0048] An inorganic thermal insulation coating comprises the following components in parts by weight: 30-50 parts of modified silicate, 10-20 parts of hollow microspheres, 5-15 parts of phase change material, 5-15 parts of polymer monomer, 1-5 parts of nano-carbon fiber, 3-8 parts of metal oxide nanowires, 5-10 parts of nano-alumina powder, 2-6 parts of aerogel, 3-8 parts of flame retardant, 5-15 parts of gelling material and 1-5 parts of stabilizer.

[0049] Among them, the hollow microspheres are one of glass hollow microspheres and ceramic hollow microspheres, the phase change material is one of paraffin and fatty acid phase change materials, the metal oxide nanowires are one of aluminum oxide metal oxide nanowires and zinc oxide metal oxide nanowires, the aerogel uses silica aerogel, the flame retardant is a phosphorus-based or nitrogen-based flame retardant, the gelling material is an inorganic polymer gelling material, and the polymer monomer is one of methyl methacrylate, styrene, and acrylate.

[0050] The particle size of the modified silicate is in the range of 1 to 100 microns, the particle size of the hollow microspheres is in the range of 10 to 150 microns, the wall thickness of the hollow microspheres is 1 to 5 microns, the phase change temperature of the phase change material is in the range of 20 to 30°C, the diameter of the nano-carbon fiber is controlled to be in the range of 10 to 100 nanometers, and the length is in the range of 1 to 10 microns, the diameter of the metal oxide nanowire is in the range of 10 to 50 nanometers, and the length is in the range of 0.1 to 1 micron, the particle size of the nano-alumina powder is in the range of 10 to 100 nanometers, and the specific surface area is in the range of 100 to 500 m 2 / g, the pore size of the aerogel is 10-100 nanometers, the porosity is greater than 90%, and the density of the aerogel is controlled at 0.1-0.3g / cm 3 , the viscosity of the gelling material is 1000 to 5000 mPa·s;

[0051] The carbon nanofibers and the metal oxide nanowires construct a continuous network structure or a three-dimensional heat-conducting network skeleton in the coating to obtain a heat-conducting network. Heat-conducting nodes are set in the heat-conducting network. These heat-conducting nodes are composed of high thermal conductivity materials. The heat-conducting network works in conjunction with the phase change material. The heat-conducting network can disperse the heat stored or released by the phase change material into the entire coating layer. The temperature of the coating layer is set to T(x, t), where x is the spatial coordinate and t is the time. Then:

[0052]

[0053] Where α is the thermal diffusivity, expressed as:

[0054]

[0055] Where ρ is the density of the coating, C p is the specific heat capacity of the coating, It is the rate of change of temperature T with time t, which indicates the rate of change of temperature with time at a certain point; It is the second-order partial derivative of temperature T with respect to the spatial coordinate x, which represents the rate of change of temperature with space, that is, the curvature of the temperature curve;

[0056] The phase change material is encapsulated by microcapsule technology, and a microcapsule with a multi-layer encapsulation structure is designed, wherein the inner layer encapsulates the phase change material, and the shell layer is made of thermal resistance material and / or the shell layer has a porous structure.

[0057] In order to specifically realize the construction of a continuous network structure or a three-dimensional thermal conductive network skeleton by carbon nanofibers and metal oxide nanowires in inorganic thermal insulation coatings, we can follow the following steps and provide a specific embodiment.

[0058] Overview of steps

[0059] Nanomaterial dispersion: Evenly disperse nanocarbon fibers and metal oxide nanowires in the coating matrix.

[0060] Constructing a thermal conductive network: forming a continuous thermal conductive network through the interconnection of nanomaterials.

[0061] Add thermal conductivity nodes: Add high thermal conductivity materials as thermal conductivity nodes at key locations in the thermal network.

[0062] Integration of phase change materials: Use microencapsulation technology to encapsulate phase change materials and distribute them evenly in the coating.

[0063] Optimize thermal properties: Optimize the thermal properties of the coating by adjusting the proportion and structure of each component.

[0064] Example

[0065] Material:

[0066] Nanocarbon fibers: 10-50 μm in length and 50-100 nm in diameter;

[0067] Metal oxide nanowires (such as aluminum oxide nanowires): length 5-20 μm, diameter 10-50 nm;

[0068] High thermal conductivity materials (such as silver nanoparticles): average particle size 50-100nm;

[0069] Phase change material (such as paraffin): melting point 30-50℃;

[0070] Microcapsule shell material (such as silica): has a porous structure with a pore size of 1-10nm

[0071] Preparation process:

[0072] Dispersion of nanomaterials: 0.5 wt% of carbon nanofibers and 0.3 wt% of metal oxide nanowires were dispersed in the coating matrix by ultrasonic treatment for 30 min.

[0073] Constructing a thermal conductive network: Through mechanical stirring and heat treatment (80°C, 1 hour), the nanomaterials form a continuous network structure in the coating.

[0074] Adding thermal conductive nodes: 0.2 wt% of silver nanoparticles were added to the thermal conductive network as thermal conductive nodes and attached to the nanofibers and nanowires by chemical deposition.

[0075] Encapsulated phase change material: Paraffin is encapsulated using microencapsulation technology, the shell layer uses porous silica material, and the diameter of the microcapsule is controlled at 10-50μm.

[0076] Coating preparation: Mix the above components evenly, add an appropriate amount of coating base (such as water-based acrylic resin), and adjust the coating viscosity to a range suitable for coating.

[0077] Coating and testing: The coating is applied to the substrate to form a coating layer with a thickness of approximately 100 μm. The coating layer is subjected to a thermal performance test, and the temperature changes over time and space are recorded.

[0078] Performance test results:

[0079] Thermal diffusivity (α): By measuring the temperature response of the coating layer, it is calculated that α is approximately 0.15 mm2 / s.

[0080] Paint density (ρ): about 1.2g / cm 3 .

[0081] Specific heat capacity (Cp): Approximately 1.5 J / g·K as measured by differential scanning calorimetry.

[0082] Through the above examples, we have successfully constructed an inorganic thermal insulation coating with a continuous thermal conductive network and phase change material working together. This coating achieves excellent thermal management performance by optimizing parameters such as thermal diffusivity, density, and specific heat capacity.

[0083] Example 1

[0084] An inorganic thermal insulation coating includes the following components in parts by weight: 30 parts of modified silicate (Huarong Kechuang 31), 10 parts of hollow microspheres, 5 parts of phase change material, 5 parts of polymer monomer, 1 part of nano-carbon fiber (Suzhou Tanfeng Graphene Technology Co., Ltd.), 3 parts of metal oxide nanowires (Shanghai Naio Nano Technology Co., Ltd.), 5 parts of nano-alumina powder, 2 parts of aerogel, 3 parts of flame retardant, 5 parts of gelling material, and 1 part of stabilizer.

[0085] Among them, the hollow microspheres are glass hollow microspheres (Hebei Kaicong Building Materials Technology Co., Ltd.), the phase change material is a paraffin phase change material (paraffin mainly composed of straight-chain alkanes, Forsman), the metal oxide nanowires are aluminum oxide metal oxide nanowires, the aerogel uses silica aerogel, the flame retardant is a phosphorus-based flame retardant (tributyl phosphate), the gelling material is an inorganic polymer gelling material (polymerized aluminum silicate), and the polymer monomer is methyl methacrylate (Gade Chemical).

[0086] The embodiment also provides a method for preparing an inorganic thermal insulation coating, which is characterized by comprising the following steps:

[0087] S1: Using an ultrasonic reactor to carry out a modification reaction, the base silicate raw material and the modifier (dimethyl silicone oil) are mixed, stirred and reacted at 60°C, and ultrasonic stirring is carried out at a frequency of 40 kHz for 4 hours. After the reaction is completed, the modified silicate powder is obtained by filtration, washing with deionized water three times, and then drying at 80°C for 4 hours.

[0088] S2: The hollow microspheres were dispersed in anhydrous ethanol, and a silane coupling agent was added for surface grafting. The mixture was stirred at 200 rpm at room temperature (25°C) for 3 hours. The hollow microspheres were dispersed in nano-silica sol for secondary coating, and then dried at 60°C for 10 hours.

[0089] S3: The phase change material and polymer monomer mixture was sprayed into hot air through an electrospray device at a spray rate of 5 mL / min and the hot air temperature was 150°C. It was dried instantly to form microcapsules. After the reaction was completed, the mixture was centrifuged at a speed of 3000 rpm for 7 minutes, washed with ethanol three times, and then dried at 40°C for 6 hours to obtain phase change microcapsules.

[0090] S4: Mix the modified silicate powder, gelling material, stabilizer (quaternary ammonium salt stabilizer) and a small amount of water, and stir in a high-speed disperser at a medium speed of 800 rpm for 30 minutes to form a uniform base slurry;

[0091] S5: Add nano-carbon fibers, metal oxide nanowires, nano-alumina powder and aerogel to the base slurry in sequence and perform ultrasonic dispersion at a frequency of 20 kHz for 10 minutes. After each addition, increase the stirring speed to 2000 rpm and disperse for 10 minutes.

[0092] S6: After ensuring that the nano-components are fully dispersed, slowly add the phase change microcapsules and the surface-treated hollow microspheres, reduce the stirring speed to 800 rpm, and continue stirring for 20 minutes to ensure that the microcapsules and hollow microspheres are evenly distributed in the slurry without destroying its structure;

[0093] S7: Finally, flame retardant compounding technology is used to compound multiple flame retardants. The compounded flame retardant is added to the mixed slurry and stirred at 200 rpm for 5 minutes to ensure that the flame retardant is evenly dispersed and fully mixed with other components.

[0094] S8: Add a thickener (hydrogenated castor oil) or a pH regulator (AMP-95 (2-amino-2-methyl-1-propanol)) to adjust the viscosity and pH value, let the evenly mixed coating stand for 2 hours to eliminate bubbles generated during the stirring process, and then dry it naturally at room temperature to obtain an inorganic thermal insulation coating.

[0095] Example 2

[0096] An inorganic thermal insulation coating comprises the following components in parts by weight: 35 parts of modified silicate, 13 parts of hollow microspheres, 7 parts of phase change material, 9 parts of polymer monomer, 2 parts of nano-carbon fiber, 5 parts of metal oxide nanowires, 7 parts of nano-alumina powder, 4 parts of aerogel, 5 parts of flame retardant, 8 parts of gelling material, and 2 parts of stabilizer.

[0097] Among them, the hollow microspheres are ceramic hollow microspheres, the phase change material is a fatty acid phase change material (stearic acid, Hebei Jinxu New Materials Technology Co., Ltd.), the metal oxide nanowires are zinc oxide metal oxide nanowires (Nanjing Xianfeng Nanomaterials Technology Co., Ltd.), the aerogel uses silica aerogel, the flame retardant is a nitrogen-based flame retardant (Shandong Xurui New Materials Co., Ltd.), the gelling material is an inorganic polymer gelling material (polymerized aluminum silicate), and the polymer monomer is styrene.

[0098] The embodiment also provides a method for preparing an inorganic thermal insulation coating, which is characterized by comprising the following steps:

[0099] S1: Using an ultrasonic reactor to carry out a modification reaction, the base silicate raw material and the modifier are mixed, stirred and reacted at 65°C, and ultrasonic stirring is carried out at a frequency of 40 kHz for 5 hours. After the reaction is completed, the modified silicate powder is obtained by filtration, washing with deionized water four times, and then drying at 80°C for 4 hours;

[0100] S2: The hollow microspheres were dispersed in anhydrous ethanol, and a silane coupling agent was added for surface grafting. The mixture was stirred at 250 rpm for 4 hours at room temperature (25°C). The hollow microspheres were dispersed in nano-silica sol for secondary coating, and then dried at 60°C for 11 hours.

[0101] S3: The phase change material and polymer monomer mixture was sprayed into hot air through an electrospray device at a spray rate of 5 mL / min and the hot air temperature was 150°C. It was dried instantly to form microcapsules. After the reaction was completed, the mixture was centrifuged at a speed of 3200 rpm for 8 minutes, washed with ethanol 4 times, and then dried at 45°C for 7 hours to obtain phase change microcapsules.

[0102] S4: Mix the modified silicate powder, gelling material, stabilizer and a small amount of water, and stir in a high-speed disperser at a medium speed of 850 rpm for 35 minutes to form a uniform base slurry;

[0103] S5: Add nano-carbon fibers, metal oxide nanowires, nano-alumina powder and aerogel to the base slurry in sequence and perform ultrasonic dispersion at a frequency of 20 kHz for 12 minutes. After each addition, increase the stirring speed to 2000 rpm and disperse for 12 minutes.

[0104] S6: After ensuring that the nano-components are fully dispersed, slowly add the phase change microcapsules and the surface-treated hollow microspheres, reduce the stirring speed to 800 rpm, and continue stirring for 24 minutes to ensure that the microcapsules and hollow microspheres are evenly distributed in the slurry without destroying its structure;

[0105] S7: Finally, flame retardant compounding technology is used to compound multiple flame retardants. The compounded flame retardants are added to the mixed slurry and stirred at 300 rpm for 7 minutes to ensure that the flame retardants are evenly dispersed and fully mixed with other components.

[0106] S8: Add a thickener or pH regulator to adjust the viscosity and pH value, let the evenly mixed coating stand for 3 hours to eliminate bubbles generated during the stirring process, and then dry it naturally at room temperature to obtain an inorganic thermal insulation coating.

[0107] Example 3

[0108] An inorganic thermal insulation coating comprises the following components in parts by weight: 40 parts of modified silicate, 18 parts of hollow microspheres, 12 parts of phase change material, 13 parts of polymer monomer, 14 parts of nano-carbon fibers, 6 parts of metal oxide nanowires, 9 parts of nano-alumina powder, 5 parts of aerogel, 6 parts of flame retardant, 11 parts of gelling material, and 3 parts of stabilizer.

[0109] Among them, the hollow microspheres are glass hollow microspheres, the phase change material is a paraffin phase change material, the metal oxide nanowires are aluminum oxide metal oxide nanowires, the aerogel is silica aerogel, the flame retardant is a phosphorus-based flame retardant, the gelling material is an inorganic polymer gelling material, and the polymer monomer is acrylate.

[0110] The embodiment also provides a method for preparing an inorganic thermal insulation coating, which is characterized by comprising the following steps:

[0111] S1: Using an ultrasonic reactor to carry out a modification reaction, the base silicate raw material and the modifier are mixed, stirred and reacted at 70°C, and ultrasonic stirring is carried out at a frequency of 40 kHz for 5 hours. After the reaction is completed, the modified silicate powder is obtained by filtration, washing with deionized water four times, and then drying at 80°C for 4 hours;

[0112] S2: The hollow microspheres were dispersed in anhydrous ethanol, and a silane coupling agent was added for surface grafting. The mixture was stirred at 300 rpm at room temperature (25°C) for 5 hours. The hollow microspheres were dispersed in nano-silica sol for secondary coating, and then dried at 60°C for 11 hours.

[0113] S3: The phase change material and polymer monomer mixture was sprayed into hot air through an electrospray device at a spray rate of 5 mL / min and the hot air temperature was 150°C. It was dried instantly to form microcapsules. After the reaction was completed, the mixture was centrifuged at a speed of 3700 rpm for 8 minutes, washed with ethanol 4 times, and then dried at 45°C for 8 hours to obtain phase change microcapsules.

[0114] S4: Mix the modified silicate powder, gelling material, stabilizer and a small amount of water, and stir in a high-speed disperser at a medium speed of 900 rpm for 38 minutes to form a uniform base slurry;

[0115] S5: Add nano-carbon fibers, metal oxide nanowires, nano-alumina powder and aerogel to the base slurry in sequence and perform ultrasonic dispersion at a frequency of 20 kHz for 13 minutes. After each addition, increase the stirring speed to 2000 rpm and disperse for 13 minutes.

[0116] S6: After ensuring that the nano-components are fully dispersed, slowly add the phase change microcapsules and the surface-treated hollow microspheres, reduce the stirring speed to 800 rpm, and continue stirring for 28 minutes to ensure that the microcapsules and hollow microspheres are evenly distributed in the slurry without destroying its structure;

[0117] S7: Finally, flame retardant compounding technology is used to compound multiple flame retardants. The compounded flame retardants are added to the mixed slurry and stirred at 400 rpm for 8 minutes to ensure that the flame retardants are evenly dispersed and fully mixed with other components.

[0118] S8: Add a thickener or pH regulator to adjust the viscosity and pH value, let the evenly mixed coating stand for 3 hours to eliminate bubbles generated during the stirring process, and then dry it naturally at room temperature to obtain an inorganic thermal insulation coating.

[0119] Example 4

[0120] An inorganic thermal insulation coating comprises the following components in parts by weight: 50 parts of modified silicate, 20 parts of hollow microspheres, 15 parts of phase change material, 15 parts of polymer monomer, 5 parts of nano-carbon fiber, 8 parts of metal oxide nanowires, 10 parts of nano-alumina powder, 6 parts of aerogel, 8 parts of flame retardant, 15 parts of gelling material, and 5 parts of stabilizer.

[0121] Among them, the hollow microspheres are glass hollow microspheres, the phase change material is a paraffin phase change material, the metal oxide nanowires are aluminum oxide metal oxide nanowires, the aerogel is silica aerogel, the flame retardant is a phosphorus-based flame retardant, the gelling material is an inorganic polymer gelling material, and the polymer monomer is acrylate.

[0122] The embodiment also provides a method for preparing an inorganic thermal insulation coating, which is characterized by comprising the following steps:

[0123] S1: Using an ultrasonic reactor to carry out a modification reaction, the base silicate raw material and the modifier are mixed, stirred and reacted at 80°C, and ultrasonic stirring is carried out at a frequency of 40 kHz for 6 hours. After the reaction is completed, the modified silicate powder is obtained by filtration, washing with deionized water 5 times, and then drying at 80°C for 4 hours;

[0124] S2: The hollow microspheres were dispersed in anhydrous ethanol, and a silane coupling agent was added for surface grafting. The mixture was stirred at 400 rpm at room temperature (25°C) for 6 hours. The hollow microspheres were dispersed in nano-silica sol for secondary coating, and then dried at 60°C for 12 hours.

[0125] S3: The phase change material and polymer monomer mixture was sprayed into hot air through an electrospray device at a spray rate of 5 mL / min and the hot air temperature was 150°C. It was dried instantly to form microcapsules. After the reaction was completed, the mixture was centrifuged at a speed of 4000 rpm for 10 minutes, washed with ethanol five times, and then dried at 50°C for 9 hours to obtain phase change microcapsules.

[0126] S4: Mix the modified silicate powder, gelling material, stabilizer and a small amount of water, and stir in a high-speed disperser at a medium speed of 1000 rpm for 40 minutes to form a uniform base slurry;

[0127] S5: Add nano-carbon fibers, metal oxide nanowires, nano-alumina powder and aerogel to the base slurry in sequence and perform ultrasonic dispersion at a frequency of 20 kHz for 15 minutes. After each addition, increase the stirring speed to 2000 rpm and disperse for 15 minutes.

[0128] S6: After ensuring that the nano-components are fully dispersed, slowly add the phase change microcapsules and the surface-treated hollow microspheres, reduce the stirring speed to 800 rpm, and continue stirring for 30 minutes to ensure that the microcapsules and hollow microspheres are evenly distributed in the slurry without destroying its structure;

[0129] S7: Finally, flame retardant compounding technology is used to compound multiple flame retardants. The compounded flame retardant is added to the mixed slurry and stirred at 500 rpm for 10 minutes to ensure that the flame retardant is evenly dispersed and fully mixed with other components.

[0130] S8: Add a thickener or pH regulator to adjust the viscosity and pH value, let the evenly mixed coating stand for 4 hours to eliminate bubbles generated during the stirring process, and then dry it naturally at room temperature to obtain an inorganic thermal insulation coating.

[0131] Example 5

[0132] On the basis of Example 4, the hollow microbeads are treated with magnetism or conductivity, and the surfaces of the hollow microbeads are treated so as to be linearly arranged in the coating. An external magnetic field or electric field is used to guide the hollow microbeads to be linearly arranged in the coating, so that the hollow microbeads move in a direction and are arranged in an orderly manner in the coating to form an ordered thermal insulation layer. The hollow microbeads are composed of multiple small molecule clusters, and these small molecule clusters are connected by weak interaction forces, thereby maintaining the stability of the microbead structure while improving the thermal insulation performance.

[0133] The specific steps are as follows:

[0134] S1: Prepare modified silicate powder according to the method in Example 4.

[0135] S2: Surface modification of hollow microbeads. The hollow microbeads are dispersed in anhydrous ethanol, and a silane coupling agent is first added for surface grafting. After stirring and reacting for 6 hours, a secondary coating is performed. During the secondary coating process, materials with magnetic or electrical responses, such as magnetic nanoparticles (such as Fe3O4 nanoparticles) or conductive nanoparticles (such as carbon nanotubes), are added to make the hollow microbeads magnetic or conductive. The specific data is: 2 grams of Fe3O4 nanoparticles or 1 gram of carbon nanotubes are added to every 100 grams of hollow microbeads to ensure that the surface of the hollow microbeads is evenly covered with a layer of responsive material.

[0136] S3: preparing phase change microcapsules, the method is the same as step S3 in Example 4.

[0137] S4: Prepare basic slurry according to the method in Example 4.

[0138] S5: Before adding the nano-components, pre-treat the magnetic or conductive hollow microspheres using an external magnetic field (magnetic induction intensity of 0.5T) or electric field (electric field intensity of 1000V / cm) to linearly align them in the slurry. Maintaining the magnetic or electric field, add nano-carbon fibers, metal oxide nanowires, nano-alumina powder, and aerogel to the base slurry in sequence, performing ultrasonic dispersion and high-speed stirring to ensure that the components are evenly dispersed and the hollow microspheres maintain linear alignment.

[0139] S6: After ensuring that the nanocomponents and hollow microspheres are fully dispersed and orderly arranged, slowly add the phase change microcapsules, reduce the stirring speed to 800 rpm, and continue stirring for 30 minutes to ensure that the microcapsules are evenly distributed in the slurry without destroying its structure and the orderly arrangement of the hollow microspheres.

[0140] S7: Add flame retardant according to the method in Example 4 and stir evenly.

[0141] S8: Add a thickener or pH adjuster to adjust the viscosity and pH value. Let the mixed coating stand for 6 hours (under the influence of an external magnetic field or electric field) to eliminate bubbles generated during the stirring process and ensure the stable and orderly arrangement of the hollow microspheres. Finally, dry naturally at room temperature to obtain an inorganic thermal insulation coating with an orderly thermal insulation layer.

[0142] Through the above steps, this embodiment successfully achieves the magnetic or conductive treatment of the hollow microspheres and their linear arrangement in the coating, further improving the thermal insulation performance of the inorganic thermal insulation coating.

[0143] Comparative Example 1

[0144] An inorganic thermal insulation coating and a preparation method thereof are basically the same as those of Example 4, except that hollow microspheres and their use in the preparation method are removed.

[0145] Comparative Example 2

[0146] An inorganic thermal insulation coating and a preparation method thereof are basically the same as those of Example 4, except that the phase change material and polymer monomer are removed, and the use of microcapsules in the preparation method is removed.

[0147] Comparative Example 3

[0148] An inorganic thermal insulation coating and a preparation method thereof are basically the same as those in Example 4, except that the nano-carbon fibers and metal oxide nanowires are removed.

[0149] Comparative Example 4

[0150] An inorganic thermal insulation coating and a preparation method thereof are basically the same as those of Example 4, except that the use of the flame retardant is eliminated.

[0151] The inorganic thermal insulation coatings prepared in Examples 1 to 4 and Comparative Examples 1 to 4 were tested, and the test standards were as follows:

[0152] Basic performance testing standards for inorganic coatings

[0153] GB / T 9756-2018: General Technical Requirements for Interior Wall Paints. This standard specifies the basic requirements, test methods, inspection rules, marking, packaging, and storage for interior wall paints. For thermal insulation coatings, the test methods for properties such as water resistance, alkali resistance, and scrub resistance can be referenced.

[0154] Thermal insulation material testing standards

[0155] GB / T 10294-2008: Insulating materials - Determination of steady-state thermal resistance and related properties - Guarded hot plate method, applicable to the determination of thermal resistance and thermal conductivity of materials under steady-state conditions.

[0156] GB / T 8811-2008: Test method for dimensional stability of rigid foam plastics, which can be used to evaluate the dimensional stability of thermal insulation coatings.

[0157] Fire performance testing standards

[0158] GB 8624-2012: Classification of combustion performance of building materials and products. For inorganic thermal insulation coatings, fire resistance is an important testing indicator.

[0159] The results are shown in Table 1:

[0160] Table 1

[0161]

[0162]

[0163] Through the above Table 1, it can be directly determined that in Examples 1 to 4, the thermal conductivity is about 0.032W / (m·K), the thermal insulation performance is good, and the water resistance of all embodiments is excellent, and no abnormalities are found after 288 hours of testing. This shows that these four embodiments are stable and reliable in water resistance. The fire protection grade of all embodiments is Class A, indicating that they have achieved the same high standard in fire resistance. The adhesion of all embodiments is 1.6MPa, indicating that these four embodiments are consistent in the adhesion ability between the coating and the substrate, and all perform excellently;

[0164] Reference Figure 1-3The thermal conductivity of Example 5 decreased compared to Example 4, from 0.032 W / (m·K) to 0.028 W / (m·K). This indicates that the coating's thermal insulation properties have been significantly improved through magnetic or conductive treatment and the linear arrangement of hollow microspheres. This reduction in thermal conductivity means the coating transfers less heat at the same temperature difference, resulting in better insulation.

[0165] The water resistance test time of Example 5 was extended from 288 hours in Example 4 to 336 hours without any abnormality, indicating that the water resistance of the coating has been enhanced. This is because the linearly arranged hollow microspheres have a more compact structure and can better resist water penetration.

[0166] The fire retardancy of Examples 4 and 5 is maintained at Class A, indicating that the magnetic or conductive treatment and the linear arrangement of the hollow microspheres have no negative impact on the fire retardancy of the coating.

[0167] The adhesion of Example 5 is improved compared to Example 4, increasing from 1.6 MPa to 1.7 MPa. This is because the contact between the linearly arranged hollow microspheres and the substrate is more uniform and close, thereby enhancing the adhesion of the coating.

[0168] In Example 4 and Comparative Example 1, where all other conditions are the same, Comparative Example 1 removes the hollow microspheres and their use in the preparation method. After final testing, the thermal conductivity of Example 4 is 0.032W / (m·K), while the thermal conductivity of Comparative Example 1 is 0.045W / (m·K). The thermal conductivity of Comparative Example 1 is higher, indicating that its thermal insulation performance is relatively poor and it transfers more heat. Example 4 showed no abnormalities after 288 hours of water resistance testing, while Comparative Example 1 showed blistering after 144 hours. This shows that the water resistance of Example 4 is significantly better than that of Comparative Example 1. The fire resistance grade of Example 4 is A, while the fire resistance grade of Comparative Example 1 is B1. Class A fire resistance is better than Class B1, indicating that Example 4 performs better in fire protection. The adhesion of Example 4 is 1.6MPa, while the adhesion of Comparative Example 1 is 1.3MPa. The adhesion of Example 4 is higher, indicating that its bonding with the substrate is more solid.

[0169] Comparative Example 2 removes the phase change material and polymer monomers, and removes the use of microcapsules in the preparation method of the two. In the comparative analysis of the data of Example 4 and Comparative Example 2, the thermal conductivity of Example 4 is 0.032W / (m·K), while the thermal conductivity of Comparative Example 2 is 0.038W / (m·K). The thermal conductivity of Comparative Example 2 is slightly higher, but the difference is not large, indicating that the two are similar in thermal insulation performance. Example 4 showed no abnormalities after 288 hours of water resistance testing, while Comparative Example 2 showed no abnormalities after 272 hours. Although Comparative Example 2 also showed good water resistance, Example 4 had a longer water resistance time and a slight advantage. Both are Class A, indicating that the two are equivalent in fire resistance. The adhesion of Example 4 is 1.6MPa, while the adhesion of Comparative Example 2 is 1.4MPa. The adhesion of Example 4 is slightly higher, but the difference with Comparative Example 2 is not large.

[0170] In Comparative Example 3, the carbon nanofibers and metal oxide nanowires were removed. The thermal conductivity of Comparative Example 3 was 0.040W / (m·K), and the thermal conductivity of Example 4 was 0.032W / (m·K). The thermal conductivity of Comparative Example 3 is higher, indicating that its thermal insulation performance is relatively poor; Example 4 showed no abnormalities after 288 hours of water resistance test, while Comparative Example 3 showed peeling after 216 hours. This shows that the water resistance of Example 4 is significantly better than that of Comparative Example 3; both are Class A, indicating that the two are equivalent in terms of fire resistance; the adhesion of Example 4 is 1.6MPa, while the adhesion of Comparative Example 3 is 1.2MPa. The adhesion of Example 4 is higher, indicating that its bond with the substrate is more solid.

[0171] In Comparative Example 4, the use of flame retardants was eliminated, and its thermal conductivity after testing was 0.035W / (m·K). The thermal conductivity of Comparative Example 4 is slightly higher, but the difference is not large, indicating that the two are similar in thermal insulation performance; Example 4 has no abnormalities after 288 hours of water resistance testing, while Comparative Example 4 has no abnormalities after 268 hours. Although Comparative Example 4 also shows good water resistance, Example 4 has a longer water resistance time, which is slightly superior; Example 4 has a fire rating of A, while Comparative Example 4 has a fire rating of B2. Class A fire resistance is better than Class B2, indicating that Example 4 performs better in fire protection; Example 4 has an adhesion of 1.6MPa, while Comparative Example 4 has an adhesion of 1.5MPa. The adhesion of Example 4 is slightly higher, but the difference from Comparative Example 4 is not large.

[0172] In summary, Example 4 exhibited superior or comparable performance to Comparative Examples 1 through 4 in key performance indicators such as thermal conductivity, water resistance, fire rating, and adhesion. In particular, Example 4 significantly outperformed some of the comparative examples in terms of water resistance and fire rating. These results demonstrate that the inorganic thermal insulation coating of Example 4 possesses superior overall performance.

[0173] In the present invention, modified silicate is used as the base material, and is modified through ultrasonic reaction to improve the thermal stability and dispersibility of the silicate. Hollow microspheres are introduced as the main thermal insulation filler, and their low thermal conductivity and lightweight properties are used to improve the thermal insulation performance of the coating. Phase change materials (such as paraffin, fatty acids, etc.) are added and encapsulated through microencapsulation technology to absorb or release heat at a specific temperature to stabilize temperature fluctuations. Combined with thermal conductive network materials such as nano-carbon fibers and metal oxide nanowires, local heat is quickly dispersed to prevent overheating. Inorganic polymer gelling materials are used as binders to ensure the stability and durability of the coating. Flame retardants are added to improve the fire rating of the coating, and the flame retardant effect is optimized through compounding technology.

[0174] Furthermore, modified silicate powder is prepared through ultrasonic reaction and meticulous filtration, washing, and drying steps. Hollow microspheres are surface-grafted and secondary coated to enhance their dispersibility and binding to the base material. Phase-change microcapsules are prepared using electrospray technology to ensure the stability and uniform distribution of the phase-change material in the coating. The base slurry is prepared in a high-speed disperser, and ultrasonic dispersion and high-speed stirring are used to ensure uniform dispersion of the nanocomponents. Phase-change microcapsules and hollow microspheres are added under specific conditions to avoid disrupting their structure and ensure uniform distribution in the slurry.

[0175] The fifth embodiment is further innovative in that the hollow microspheres are treated to be magnetic or conductive and an external magnetic field or electric field is used to guide them to be arranged linearly in the coating to form an ordered thermal insulation layer, thereby significantly improving the thermal insulation performance.

[0176] Through the synergistic effect of modified silicates, hollow microspheres, phase change materials and nano-thermal conductive networks, the thermal conductivity of the coating is significantly reduced, and the thermal insulation performance is excellent. The linear arrangement of hollow microspheres in Example 5 further enhances the thermal insulation effect. Through sophisticated preparation technology and formula design, the coating exhibits excellent water resistance and can maintain stable performance for a long time. At the same time, the use of inorganic polymer gelling materials also improves the durability of the coating. The addition of phosphorus or nitrogen flame retardants, combined with compounding technology, enables the coating to achieve a higher fire protection level, ensuring safe use.

[0177] Through a rational formulation and preparation process, the coating achieves strong adhesion to the substrate, facilitates application, and is readily applicable. The use of inorganic materials reduces harmful emissions, complying with environmental requirements. Furthermore, the excellent thermal insulation properties help reduce energy consumption and achieve energy conservation and emission reduction. The magnetic or conductive treatment and linear arrangement of hollow microspheres bring new ideas and methods to the field of inorganic thermal insulation coatings, demonstrating significant innovation and application prospects.

[0178] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. An inorganic thermal insulation coating, characterized in that: The invention comprises the following components in parts by weight: 30-50 parts of modified silicate, 10-20 parts of hollow microspheres, 5-15 parts of phase change material, 5-15 parts of polymer monomer, 1-5 parts of nano-carbon fiber, 3-8 parts of metal oxide nanowire, 5-10 parts of nano-alumina powder, 2-6 parts of aerogel, 3-8 parts of flame retardant, 5-15 parts of gelling material and 1-5 parts of stabilizer. The carbon nanofibers and the metal oxide nanowires construct a continuous network structure or a three-dimensional heat-conducting network skeleton in the coating to obtain a heat-conducting network. Heat-conducting nodes are provided in the heat-conducting network. The heat-conducting nodes are made of silver nanoparticles and are composed of high-thermal-conductivity materials. The heat-conducting network works in conjunction with the phase change material to disperse the heat stored or released by the phase change material into the entire coating layer. The phase change material is encapsulated by microencapsulation technology, and a multi-layer encapsulation structure of microcapsules is designed, wherein the inner layer encapsulates the phase change material, and the shell layer is made of thermal resistance material and / or the shell layer has a porous structure; The hollow microspheres are one of glass hollow microspheres and ceramic hollow microspheres, the phase change material is one of paraffin and fatty acid phase change materials, the metal oxide nanowires are one of aluminum oxide metal oxide nanowires and zinc oxide metal oxide nanowires, the aerogel is silica aerogel, the flame retardant is a phosphorus-based or nitrogen-based flame retardant, the gelling material is an inorganic polymer gelling material, and the polymer monomer is one of methyl methacrylate, styrene, and acrylate.

2. The inorganic thermal insulation coating according to claim 1, characterized in that: The invention comprises the following components in parts by weight: 40 parts of modified silicate, 14 parts of hollow microspheres, 7 parts of phase change material, 8 parts of polymer monomer, 3 parts of nano-carbon fiber, 4 parts of metal oxide nanowire, 7 parts of nano-alumina powder, 4 parts of aerogel, 5 parts of flame retardant, 11 parts of gelling material and 3 parts of stabilizer.

3. The inorganic thermal insulation coating according to claim 1, characterized in that: The particle size of the modified silicate is in the range of 1 to 100 microns, the particle size of the hollow microspheres is in the range of 10 to 150 microns, the wall thickness of the hollow microspheres is 1 to 5 microns, the phase change temperature of the phase change material is in the range of 20 to 30°C, the diameter of the nano-carbon fiber is controlled to be in the range of 10 to 100 nanometers, and the length is in the range of 1 to 10 microns, the diameter of the metal oxide nanowire is in the range of 10 to 50 nanometers, and the length is in the range of 0.1 to 1 micron, the particle size of the nano-alumina powder is in the range of 10 to 100 nanometers, and the specific surface area is in the range of 100 to 500 m 2 / g, the pore size of the aerogel is 10-100 nanometers, the porosity is greater than 90%, and the density of the aerogel is controlled at 0.1-0.3 g / cm 3 The viscosity of the gelling material is 1000 to 5000 mPa·s.

4. A method for preparing the inorganic thermal insulation coating according to any one of claims 1 to 3, characterized in that: The following steps are involved: S1: Using an ultrasonic reactor to carry out a modification reaction, the base silicate raw material is mixed with the modifier, and stirred for reaction. After the reaction is completed, the modified silicate powder is obtained by filtering, washing and drying for use; S2: The hollow microspheres are dispersed in anhydrous ethanol, and a silane coupling agent is added for surface grafting. After stirring and reacting at room temperature for several hours, the hollow microspheres are dispersed in nano-silica sol for secondary coating, and then dried; S3: The phase change material and polymer monomer mixture is sprayed into hot air through an electrospray device, and dried instantly to form microcapsules. After the reaction is completed, the phase change microcapsules are obtained by centrifugation, washing, and drying; S4: Mix the modified silicate powder, gelling material, stabilizer and a small amount of water, and stir at medium speed in a high-speed disperser to form a uniform base slurry; S5: adding nano-carbon fibers, metal oxide nanowires, nano-alumina powder and aerogel to the base slurry in sequence and performing ultrasonic dispersion, increasing the stirring speed after each addition; S6: After ensuring that the nano-components are fully dispersed, slowly add the phase change microcapsules and the surface treated hollow microbeads, reduce the stirring speed to low speed, and continue stirring to ensure that the microcapsules and hollow microbeads are evenly distributed in the slurry without destroying its structure; S7: Finally, flame retardant compounding technology is used to compound multiple flame retardants, and the compounded flame retardants are added to the mixed slurry. Stirring is carried out to ensure that the flame retardants are evenly dispersed and fully mixed with other components to obtain an inorganic thermal insulation coating.

5. The method for preparing an inorganic thermal insulation coating according to claim 4, characterized in that: In S1, an ultrasonic reactor is used to carry out a modification reaction, wherein the basic silicate raw material and the modifier are mixed, stirred and reacted at 60-80° C., and ultrasonic stirring reaction is carried out at a frequency of 40 kHz for 4-6 hours. After the reaction is completed, the modified silicate powder is obtained by filtering, washing with deionized water 3-5 times, and then drying at 80° C. for 4 hours.

6. The method for preparing an inorganic thermal insulation coating according to claim 4, characterized in that: In the S3, the phase change material and polymer monomer mixture is sprayed into hot air through an electrospray device at a spray rate of 5 mL / min and the hot air is 150° C., and is instantly dried to form microcapsules. After the reaction is completed, the mixture is centrifuged at a speed of 3000-4000 rpm for 7-10 minutes, washed with ethanol 3-5 times, and then dried at 40-50° C. for 6-9 hours to obtain phase change microcapsules.

7. The method for preparing an inorganic thermal insulation coating according to claim 4, characterized in that: The hollow microbeads are treated with magnetism or conductivity, and the surfaces of the hollow microbeads are treated so that they are arranged linearly in the coating. An external magnetic field or electric field is used to guide the hollow microbeads to arrange linearly in the coating, so that the hollow microbeads move in a direction and are arranged in an orderly manner in the coating, forming an orderly thermal insulation layer. The hollow microbeads are composed of multiple small molecule clusters, which are connected by weak interaction forces, maintaining the stability of the microbead structure while improving the thermal insulation performance.

8. The method for preparing an inorganic thermal insulation coating according to claim 4, characterized in that: The process also includes S8: adding a thickener or a pH regulator to adjust the viscosity and pH value, allowing the uniformly mixed coating to stand for 2 to 4 hours to eliminate bubbles generated during the stirring process, and then drying naturally at room temperature.

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