Heat preservation and insulation material containing mesoporous and vacuum microbead materials and preparation method of heat preservation and insulation material

Abstract

The invention relates to the technical field of heat preservation and insulation materials, and provides a heat preservation and insulation material containing mesoporous and vacuum microbead materials and a preparation method of the heat preservation and insulation material. The heat preservation and insulation material containing the mesopores and the vacuum microbead material is prepared from the following materials in parts by weight: 20 to 25 parts of fluorocarbon resin, 15 to 20 parts of organic silicon modified acrylic resin, 8 to 12 parts of modified vacuum microbeads, 5 to 8 parts of mica powder, 3 to 5 parts of nano zirconium oxide, 1 to 2 parts of dispersing agent, 0.5 to 1 part of defoaming agent, 0.5 to 1 part of flatting agent and 0.3 to 0.5 part of thickening agent. According to the heat preservation and insulation material containing the mesopore and vacuum microbead materials and the preparation method, the hydrophobic performance of the material is improved, and the damage of water to the performance of the material is prevented, so that the heat preservation and insulation performance of the material is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of thermal insulation materials, and specifically, to a thermal insulation material containing mesoporous and vacuum microsphere materials and a preparation method thereof. Background Art

[0002] In the context of global energy tension and the increasing awareness of environmental protection, the research and application of thermal insulation materials are particularly important. As a new type of thermal insulation material, thermal insulation coatings have been widely used in the fields of architecture, industrial equipment, aerospace, etc. due to their advantages such as convenient construction, energy conservation, and environmental protection. Among them, thermal insulation coatings containing mesoporous and vacuum microsphere materials have become a research hotspot due to their unique structure and excellent performance.

[0003] Mesoporous materials are a class of porous materials with pore diameters between 2 and 50 nanometers, having a very high specific surface area and a regular and ordered pore structure. This special structure enables mesoporous materials to perform excellently in thermal insulation and can effectively inhibit heat conduction. Vacuum microspheres are ceramic particles with tiny cavities inside, and these cavities form a vacuum state inside the microspheres, greatly reducing heat transfer. Combining mesoporous materials and vacuum microspheres to prepare thermal insulation coatings can give full play to the advantages of both and achieve better thermal insulation effects.

[0004] However, mesoporous materials and vacuum microsphere materials themselves may have a certain degree of hydrophilicity, which may cause the materials to absorb water and be affected by moisture in practical applications, thereby affecting their thermal insulation performance. Therefore, how to improve the hydrophobicity of the materials and prevent the damage of moisture to the material performance is a key point in current research. Based on this, the present invention proposes a thermal insulation material containing mesoporous and vacuum microsphere materials and a preparation method thereof. Summary of the Invention

[0005] The present invention proposes a thermal insulation material containing mesoporous and vacuum microsphere materials and a preparation method thereof, which solves the problem that mesoporous materials and vacuum microsphere materials are prone to absorb water and be affected by moisture in practical applications, thereby affecting their thermal insulation performance, improves the hydrophobicity of the materials, prevents the damage of moisture to the material performance, and thus enhances the thermal insulation performance of the materials.

[0006] The technical solution of the present invention is as follows: In the first aspect, the present invention proposes a thermal insulation material containing mesoporous and vacuum microsphere materials, which comprises the following materials in parts by weight: 20 - 25 parts of fluorocarbon resin, 15 - 20 parts of organosilicon-modified acrylic resin, 8 - 12 parts of modified vacuum microspheres, 5 - 8 parts of mica powder, 3 - 5 parts of nano-zirconia, 1 - 2 parts of dispersant, 0.5 - 1 part of defoamer, 0.5 - 1 part of leveling agent, and 0.3 - 0.5 part of thickener.

[0007] As a further technical solution, the preparation method of the modified vacuum microspheres includes: mixing aluminum nitride powder and ethanol and ball-milling to obtain a nano-suspension; immersing ceramic microspheres in the suspension, and obtaining ceramic microspheres coated with aluminum nitride after ultrasonic treatment, pre-drying, and annealing; dispersing the ceramic microspheres coated with aluminum nitride in ethanol, adding tetraethyl orthosilicate, and adjusting the pH with ammonia water, and forming ceramic microspheres further coated with SiO2 after stirring reaction; immersing the ceramic microspheres further coated with SiO2 in a titanate coupling agent solution, and then performing heat treatment to obtain the modified vacuum microspheres.

[0008] As a further technical solution, the preparation method of the ceramic microspheres coated with aluminum nitride includes: mixing aluminum nitride powder and ethanol, and ball-milling at a rotation speed of 300-400 rpm for 20-24 h to obtain a nano-suspension; immersing the ceramic microspheres in the suspension, performing ultrasonic treatment at a power of 200-300 W for 30-40 min, pre-drying at 60-70 °C for 2-3 h, transferring to a vacuum furnace, maintaining the vacuum degree ≤ 10 -3 Pa, and annealing at 500-600 °C for 2-3 h to obtain the ceramic microspheres coated with aluminum nitride.

[0009] As a further technical solution, the weight part ratio of the aluminum nitride powder, ethanol, and ceramic microspheres is (5-6):(100-120):100.

[0010] As a further technical solution, the preparation method of the ceramic microspheres further coated with SiO2 includes: dispersing the ceramic microspheres coated with aluminum nitride in ethanol, adding tetraethyl orthosilicate, and adjusting the pH = 9-10 with ammonia water, and stirring and reacting at 50-60 °C for 2-3 h to form the ceramic microspheres further coated with SiO2.

[0011] As a further technical solution, the weight part ratio of the ceramic microspheres coated with aluminum nitride, ethanol, and tetraethyl orthosilicate is 1:(10-12):(0.2-0.4).

[0012] As a further technical solution, the impregnation temperature when immersing in the titanate coupling agent solution is 55-65 °C, and the impregnation time is 1-2 h; the heat treatment temperature is 120-130 °C, and the heat treatment time is 1-2 h.

[0013] As a further technical solution, the preparation steps of the titanate coupling agent solution include: dissolving the titanate coupling agent TCA-K38 in a mixed solution of ethanol and water, dropping acetic acid until the pH = 4-5, and hydrolyzing at 200-300 rpm for 30-40 min to obtain it.

[0014] As a further technical solution, the weight part ratio of the ceramic microspheres further coated with SiO2 and the titanate coupling agent solution is 100:1-2.

[0015] In a second aspect, the present invention provides a method for preparing a thermal insulation material containing mesoporous and hollow glass microsphere materials. The steps include: mixing fluorocarbon resin and organosilicon-modified acrylic resin in a certain proportion to obtain a resin matrix, adding a dispersant, an antifoaming agent, a leveling agent, a thickening agent, and nano-zirconia thereto, dispersing at a high speed of 1800 - 2000 rpm for 30 - 40 min, adding mica powder and modified hollow glass microspheres, and then switching to stirring at 700 - 800 rpm for 15 - 25 min to obtain the product.

[0016] The working principle and beneficial effects of the present invention are as follows: The thermal insulation material containing mesoporous and hollow glass microsphere materials of the present invention realizes a breakthrough improvement in the core performance of hollow glass microspheres by constructing a modified hollow glass microsphere structure with an AlN / SiO2 double-layer coating. Traditional hollow glass microsphere materials are prone to losing vacuum due to gas penetration in a humid environment. In the present invention, the AlN layer, as a high gas-barrier layer, can effectively block the penetration of water molecules and gas molecules with its dense crystal structure, maintaining the vacuum state inside the microspheres. The SiO2 layer forms a superhydrophobic interface through its chemical inertness and nanoscale rough surface, significantly reducing water adsorption. This double-layer synergistic effect enables the change rate of the thermal conductivity of the material after hydrothermal aging to be controlled within <5%, improving the durability by more than 3 times compared with traditional single-layer coated materials.

[0017] The present invention innovatively adopts the coating sequence of AlN, SiO2, and coupling agent, which is designed based on the principle of interfacial energy gradient. The AlN layer forms an initial bond with the ceramic microspheres through physical adsorption. The SiO2 layer self-assembles on the surface of the AlN layer by the sol-gel method to form an energy level gradient transition. The titanate coupling agent constructs an organic-inorganic hybrid interface layer on the surface of the SiO2 layer through its bifunctional group structure. In addition, the present invention uses the titanate coupling agent TCA-K38 for surface treatment. The alkoxy group (RO-) in its molecular structure undergoes a condensation reaction with the hydroxyl groups on the SiO2 surface to form a stable Si-O-Ti bond. The long-chain alkyl groups form an entangled network with the siloxane chains in the organosilicon-modified acrylic resin through van der Waals forces.

[0018] The present invention constructs a three-dimensional heat insulation network through the synergistic effect of hollow glass microspheres, mica powder, and nano-zirconia. The hollow glass microspheres, as the main heat insulation body, suppress gas heat conduction through the internal vacuum layer; the mica powder forms a heat conduction barrier with a layered structure, and the difference in thermal conductivity within its two-dimensional plane reaches 10 times; the nano-zirconia can achieve a reflectivity of 85% for infrared radiation through the surface plasmon resonance effect. After the three are compounded, the overall thermal conductivity of the material is reduced to 0.031 W / (m·K), improving the heat insulation performance compared with the single-component system.

[0019] The present invention adopts a compound system of fluorocarbon resin and silicone-modified acrylic resin, and forms an interpenetrating network structure through molecular chain entanglement. The C-F bond of the fluorocarbon resin provides chemical inertness, and the Si-O chain of the silicone resin enhances flexibility. The dispersant BYK-2152 makes the nano-zirconia evenly dispersed through steric hindrance effect, and the leveling agent BYK-S706 reduces the surface tension to ensure the oriented arrangement of the microspheres. This matrix design enables the material to maintain structural stability in the temperature range of -40°C to 150°C. Detailed implementation manners

[0020] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0021] It should be noted that in the present invention, the model of the fluorocarbon resin is JF-2X, purchased from Changshu 3F Zhonghao Chemical New Materials Co., Ltd.; the model of the silicone-modified acrylic resin is RB-237, purchased from Wuxi Xiyano New Materials Technology Co., Ltd.; the ceramic microspheres are purchased from Shanghai Huijing Sub-nano New Materials Co., Ltd., with an average particle size of 50 μm; the aluminum nitride powder is purchased from Shanghai Xiaohuang Nano Technology Co., Ltd.; the mica powder, 400 mesh, is purchased from Shijiazhuang Haixing Mica Powder Co., Ltd.; the nano-zirconia is purchased from Beijing Dekedaojin Technology Co., Ltd., with a particle size of 20-30 nm.

[0022] Example 1 In this embodiment, a thermal insulation material containing mesoporous and vacuum microsphere materials is provided, including the following materials in parts by weight: 22 parts of fluorocarbon resin, 17 parts of silicone-modified acrylic resin, 10 parts of modified vacuum microspheres, 6 parts of mica powder, 4 parts of nano-zirconia, 1.5 parts of dispersant, 0.7 part of defoamer, 0.7 part of leveling agent, and 0.4 part of thickener; Among them, the preparation method of the modified vacuum microspheres includes: Mix the aluminum nitride powder with ethanol, and ball mill for 22 h at a rotation speed of 350 rpm to obtain a nano-suspension; immerse the ceramic microspheres in the suspension, ultrasonically treat for 35 min at a power of 250 W, pre-dry at 65°C for 2.5 h, transfer to a vacuum furnace, and maintain the vacuum degree at 10 -3 Pa, anneal at 550°C for 2.5 h to obtain ceramic microspheres coated with aluminum nitride; the weight ratio of the aluminum nitride powder, ethanol and ceramic microspheres is 5.5:110:100; Disperse the ceramic microspheres coated with aluminum nitride in ethanol, add tetraethyl orthosilicate, and adjust the pH to 9.5 with ammonia water. Stir and react at 55 °C for 2.5 h to form ceramic microspheres further coated with SiO2. The weight ratio of the ceramic microspheres coated with aluminum nitride, ethanol, and tetraethyl orthosilicate is 1:11:0.3; Immerse the ceramic microspheres further coated with SiO2 in a titanate coupling agent solution. The impregnation temperature is 60 °C and the impregnation time is 1.5 h. Then, perform heat treatment at 125 °C for 1.5 h to obtain the modified vacuum microspheres. Dissolve the titanate coupling agent TCA-K38 in a mixed solution of ethanol and water, add acetic acid dropwise until the pH = 4.5, and hydrolyze for 35 min at 250 rpm to obtain the titanate coupling agent solution. The weight ratio of the ceramic microspheres further coated with SiO2 and the titanate coupling agent solution is 100:1.5; Among them, the dispersant is BYK-2152, the defoamer is the silicone defoamer TEGO Foamex 810, the leveling agent is BYK-S706, and the thickener is the polyurethane thickener RM-8W; A preparation method of a thermal insulation material containing mesoporous and vacuum microsphere materials, the steps include: mixing fluorocarbon resin and organosilicon-modified acrylic resin in proportion to obtain a resin matrix, adding a dispersant, a defoamer, a leveling agent, a thickener, and nano-zirconia thereto, dispersing at a high speed of 1900 rpm for 35 min, adding mica powder and modified vacuum microspheres, and switching to stirring at 750 rpm for 20 min to obtain the thermal insulation material containing mesoporous and vacuum microsphere materials.

[0023] Example 2 In this example, a thermal insulation material containing mesoporous and vacuum microsphere materials is provided, including the following materials in parts by weight: 20 parts of fluorocarbon resin, 15 parts of organosilicon-modified acrylic resin, 8 parts of modified vacuum microspheres, 5 parts of mica powder, 3 parts of nano-zirconia, 1 part of dispersant, 0.5 part of defoamer, 0.5 part of leveling agent, and 0.3 part of thickener; Among them, the preparation method of the modified vacuum microspheres includes: Mix aluminum nitride powder and ethanol, and ball mill at a rotation speed of 300 rpm for 20 h to obtain a nano-suspension. Immerse the ceramic microspheres in the suspension, perform ultrasonic treatment at a power of 200 W for 30 min, pre-dry at 60 °C for 2 h, transfer to a vacuum furnace, and keep the vacuum degree at 10 -3 Pa, anneal at 500 °C for 2 h to obtain ceramic microspheres coated with aluminum nitride. The weight ratio of aluminum nitride powder, ethanol, and ceramic microspheres is 5:100:100; Disperse the ceramic microspheres coated with aluminum nitride in ethanol, add tetraethyl orthosilicate, and adjust the pH to 9 with ammonia water. Stir and react at 50 °C for 2 h to form ceramic microspheres further coated with SiO₂. The weight ratio of the ceramic microspheres coated with aluminum nitride, ethanol, and tetraethyl orthosilicate is 1:10:0.2; Immerse the ceramic microspheres further coated with SiO₂ in a titanate coupling agent solution. The impregnation temperature is 55 °C and the impregnation time is 1 h. Then, perform heat treatment at 120 °C for 1 h to obtain the modified vacuum microspheres. Dissolve the titanate coupling agent TCA-K38 in a mixed solution of ethanol and water, add acetic acid dropwise until the pH = 4, and hydrolyze for 30 min at 200 rpm to obtain the titanate coupling agent solution. The weight ratio of the ceramic microspheres further coated with SiO₂ and the titanate coupling agent solution is 100:1; Among them, the dispersant is BYK-2152, the defoaming agent is the silicone defoaming agent TEGO Foamex 810, the leveling agent is BYK-S706, and the thickening agent is the polyurethane thickening agent RM-8W; A preparation method of a thermal insulation material containing mesoporous and vacuum microsphere materials, the steps include: mixing fluorocarbon resin and organosilicon-modified acrylic resin in proportion to obtain a resin matrix, adding a dispersant, a defoaming agent, a leveling agent, a thickening agent, and nano-zirconia thereto, dispersing at a high speed of 1800 rpm for 30 min, adding mica powder and modified vacuum microspheres, and switching to stirring at 700 rpm for 15 min to obtain the thermal insulation material containing mesoporous and vacuum microsphere materials.

[0024] Example 3 In this example, a thermal insulation material containing mesoporous and vacuum microsphere materials is provided, including the following materials in parts by weight: 25 parts of fluorocarbon resin, 20 parts of organosilicon-modified acrylic resin, 12 parts of modified vacuum microspheres, 8 parts of mica powder, 5 parts of nano-zirconia, 2 parts of dispersant, 1 part of defoaming agent, 1 part of leveling agent, and 0.5 part of thickening agent; Among them, the preparation method of the modified vacuum microspheres includes: Mix aluminum nitride powder and ethanol, and ball mill at a rotation speed of 400 rpm for 24 h to obtain a nano-suspension. Immerse the ceramic microspheres in the suspension, perform ultrasonic treatment at a power of 300 W for 40 min, pre-dry at 70 °C for 3 h, transfer to a vacuum furnace, and keep the vacuum degree at 10 -3 Pa, anneal at 600 °C for 3 h to obtain ceramic microspheres coated with aluminum nitride. The weight ratio of aluminum nitride powder, ethanol, and ceramic microspheres is 6:120:100; Disperse the ceramic microspheres coated with aluminum nitride in ethanol, add tetraethyl orthosilicate, and adjust the pH to 10 with ammonia water. Stir and react at 60 °C for 3 h to form ceramic microspheres further coated with SiO₂. The weight ratio of the ceramic microspheres coated with aluminum nitride, ethanol, and tetraethyl orthosilicate is 1:12:0.4; Immerse the ceramic microspheres re-coated with SiO2 in a titanate coupling agent solution. The impregnation temperature is 65 °C and the impregnation time is 2 h. Subsequently, heat treatment is carried out at 130 °C for 2 h to obtain the modified vacuum microspheres; dissolve the titanate coupling agent TCA-K38 in a mixed solution of ethanol and water, add acetic acid dropwise until pH = 5, and hydrolyze for 40 min at 300 rpm to obtain the titanate coupling agent solution; the weight ratio of the ceramic microspheres re-coated with SiO2 to the titanate coupling agent solution is 100:2; Among them, the dispersant is BYK-2152, the defoamer is the silicone defoamer TEGO Foamex 810, the leveling agent is BYK-S706, and the thickener is the polyurethane thickener RM-8W; A preparation method of a thermal insulation material containing mesopores and vacuum microsphere materials, the steps include: mixing fluorocarbon resin and organosilicon-modified acrylic resin in proportion to obtain a resin matrix, adding a dispersant, a defoamer, a leveling agent, a thickener and nano-zirconia thereto, dispersing at a high speed of 2000 rpm for 40 min, adding mica powder and modified vacuum microspheres, and switching to stirring at 800 rpm for 25 min to obtain the thermal insulation material containing mesopores and vacuum microsphere materials.

[0025] Example 4 In this example, a thermal insulation material containing mesopores and vacuum microsphere materials is provided, including the following materials by weight: 20 parts of fluorocarbon resin, 20 parts of organosilicon-modified acrylic resin, 8 parts of modified vacuum microspheres, 8 parts of mica powder, 3 parts of nano-zirconia, 2 parts of dispersant, 0.5 part of defoamer, 1 part of leveling agent and 0.3 part of thickener; Among them, the preparation method of the modified vacuum microspheres includes: Mix aluminum nitride powder with ethanol, and ball mill at a rotation speed of 400 rpm for 20 h to obtain a nano-suspension; immerse the ceramic microspheres in the suspension, ultrasonically treat at a power of 300 W for 30 min, pre-dry at 70 °C for 2 h, transfer to a vacuum furnace, and maintain the vacuum degree at 10 -3 Pa, anneal at 500 °C for 3 h to obtain ceramic microspheres coated with aluminum nitride; the weight ratio of aluminum nitride powder, ethanol and ceramic microspheres is 5:120:100; Disperse the ceramic microspheres coated with aluminum nitride in ethanol, add tetraethyl orthosilicate, and adjust the pH = 9 with ammonia water, and stir and react at 60 °C for 2 h to form ceramic microspheres re-coated with SiO2; the weight ratio of the ceramic microspheres coated with aluminum nitride, ethanol and tetraethyl orthosilicate is 1:12:0.2; The ceramic microspheres re-coated with SiO2 are immersed in a titanate coupling agent solution at an impregnation temperature of 55 °C and an impregnation time of 2 h, and then heat-treated at 120 °C for 2 h to obtain the modified vacuum microspheres; the titanate coupling agent TCA-K38 is dissolved in a mixed solution of ethanol and water, acetic acid is added dropwise until pH = 4, and after hydrolysis at 300 rpm for 30 min, a titanate coupling agent solution is obtained; the weight ratio of the ceramic microspheres re-coated with SiO2 to the titanate coupling agent solution is 100:2; Among them, the dispersant is BYK-2152, the defoaming agent is the silicone defoaming agent TEGO Foamex 810, the leveling agent is BYK-S706, and the thickening agent is the polyurethane thickening agent RM-8W; A preparation method of a thermal insulation material containing mesopores and vacuum microsphere materials, the steps include: mixing fluorocarbon resin and organosilicon-modified acrylic resin in proportion to obtain a resin matrix, adding a dispersant, a defoaming agent, a leveling agent, a thickening agent and nano-zirconia thereto, dispersing at a high speed of 1800 rpm for 40 min, adding mica powder and modified vacuum microspheres, and switching to stirring at 700 rpm for 25 min to obtain a thermal insulation material containing mesopores and vacuum microsphere materials.

[0026] Comparative Example 1 In Comparative Example 1, the modified vacuum microspheres were not coated with aluminum nitride; the rest was the same as in Example 1, and the preparation steps were the same as in Example 1.

[0027] Comparative Example 2 In Comparative Example 2, the modified vacuum microspheres were not coated with SiO2; the rest was the same as in Example 1, and the preparation steps were the same as in Example 1.

[0028] Comparative Example 3 In Comparative Example 3, the modified vacuum microspheres were not impregnated with a titanate coupling agent; the rest was the same as in Example 1, and the preparation steps were the same as in Example 1.

[0029] Comparative Example 4 In Comparative Example 4, the modified vacuum microspheres were first coated with SiO2 and then coated with aluminum nitride; the rest was the same as in Example 1, and the preparation steps were the same as in Example 1.

[0030] Comparative Example 5 In Comparative Example 5, the modified vacuum microspheres were not coated with aluminum nitride and SiO2; the rest was the same as in Example 1, and the preparation steps were the same as in Example 1.

[0031] Comparative Example 6 In Comparative Example 6, the modified vacuum microspheres were replaced with unmodified ceramic microspheres, and the rest was the same as in Example 1, and the preparation steps were the same as in Example 1.

[0032] Comparative Example 7 In Comparative Example 7, modified hollow microspheres were not added, and the rest was the same as in Example 1. The preparation steps were the same as in Example 1.

[0033] Comparative Example 8 In Comparative Example 8, mica powder was not added, and the rest was the same as in Example 1. The preparation steps were the same as in Example 1.

[0034] Comparative Example 9 In Comparative Example 9, nano-zirconia was not added, and the rest was the same as in Example 1. The preparation steps were the same as in Example 1.

[0035] Test Example 1: The thermal insulation materials containing mesopores and hollow microspheres prepared in Examples 1-4 and Comparative Examples 1-9 were scraped on a 3 mm sandblasted steel plate, and the coating thickness was 1.0 mm. The following tests were carried out: Thermal conductivity: The thermal conductivity was tested with reference to GB / T10295-2008. The lower the thermal conductivity, the better the heat insulation performance. Adhesion: The test was carried out with reference to GB / T 9286-2021 "Cross-Cut Test for Paints and Varnishes". The result judgment method was divided into 5 levels: 0: The cutting edges were completely smooth and none of the grids peeled off; 1: There was a little coating peeling at the intersection of the cuts, but the affected cross-cut area was not significantly greater than 5%; 2: There was coating peeling at the intersection or the edge of the cuts, and the affected cross-cut area was significantly greater than 5% and less than 15%; 3: The coating peeled off partially or completely along the cutting edge in large fragments, and on different parts of the grid, part or all peeled off, and the affected cross-cut area was significantly greater than 15% and less than 35%; 4: The coating peeled off in large fragments along the cutting edge, and some grids partially or completely peeled off, and the affected cross-cut area was significantly greater than 35% and less than 65%; 5: The affected cross-cut area was significantly greater than 65%. Chemical corrosion resistance: The samples were respectively immersed in a 5% mass concentration of NaCl solution, a 5% mass concentration of H2SO4 solution, and a 5% mass concentration of NaOH solution for 72 h, and the mass change rate of the samples was counted.

[0036] Humid heat aging performance test: The samples were placed in a thermostatic and humid box (temperature 85 °C, humidity 85% RH). After aging for 1000 hours, the change rate of the thermal conductivity was tested.

[0037] The results are shown in Table 1 below: Table 1

[0038] Combined with the foregoing content, it can be seen that in Comparative Example 1, the thermal conductivity increased significantly, the gas barrier property of the vacuum microspheres decreased, resulting in the deterioration of the heat insulation performance, and the corrosion resistance and the stability under damp heat aging decreased significantly. In Comparative Example 2, the water absorption increased, and the change rate of the thermal conductivity after damp heat aging increased to 8.9%, indicating that the SiO2 layer is crucial for hydrophobicity and long-term stability. In Comparative Example 3, the adhesion grade rose to Grade 1, and the interfacial bonding force decreased, resulting in the easy peeling of the coating, proving the enhancing effect of the titanate coupling agent on the adhesion of the resin-microsphere interface. In Comparative Example 4, the adhesion grade rose to Grade 2, and the interfacial bonding force decreased, verifying the key role of the order of AlN→SiO2→coupling agent in the interlayer compatibility. In Comparative Example 5, the comprehensive performance was the worst, indicating the irreplaceability of the multi-layer coating structure. In Comparative Example 6, the adhesion grade was 4, and the coating peeled off severely, indicating the decisive influence of the modification process on the interfacial bonding force. In Comparative Example 7, the thermal conductivity soared to 0.068 W / (m·K), and the resistance to damp heat aging was the worst, highlighting the core contribution of the vacuum microspheres to the heat insulation performance. In Comparative Example 8, the thermal conductivity increased to 0.043 W / (m·K), and the absence of the barrier effect of the flaky mica led to the acceleration of heat transfer. In Comparative Example 9, the infrared reflectance decreased, and the thermal conductivity was 0.047 W / (m·K), verifying the shielding effect of the nano-ZrO2 on thermal radiation.

[0039] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A thermal insulation material containing mesoporous and vacuum microsphere materials, characterized in that, It includes the following materials in parts by weight: 20 - 25 parts of fluorocarbon resin, 15 - 20 parts of organosilicon-modified acrylic resin, 8 - 12 parts of modified hollow microspheres, 5 - 8 parts of mica powder, 3 - 5 parts of nano-zirconia, 1 - 2 parts of dispersant, 0.5 - 1 part of defoamer, 0.5 - 1 part of leveling agent, and 0.3 - 0.5 part of thickener.

2. The thermal insulation material containing mesoporous and vacuum microsphere materials according to claim 1, characterized in that The preparation method of the modified hollow microspheres includes: mixing aluminum nitride powder and ethanol for ball milling to obtain a nano-suspension; immersing ceramic microspheres in the suspension, and obtaining ceramic microspheres coated with aluminum nitride after ultrasonic treatment, pre-drying, and annealing; dispersing the ceramic microspheres coated with aluminum nitride in ethanol, adding tetraethyl orthosilicate, and adjusting the pH with ammonia water, and forming ceramic microspheres re-coated with SiO2 after stirring and reacting; immersing the ceramic microspheres re-coated with SiO2 in a titanate coupling agent solution, and then performing heat treatment to obtain the modified hollow microspheres.

3. The thermal insulation material containing mesoporous and vacuum microsphere materials according to claim 2, characterized in that, The preparation method of the ceramic microspheres coated with aluminum nitride includes: mixing aluminum nitride powder with ethanol, ball-milling for 20 - 24 h at a rotation speed of 300 - 400 rpm to obtain a nano suspension; immersing the ceramic microspheres in the suspension, performing ultrasonic treatment for 30 - 40 min at a power of 200 - 300 W, pre-drying at 60 - 70 °C for 2 - 3 h, transferring to a vacuum furnace, maintaining the vacuum degree ≤ 10 -3 Pa, annealing at 500 - 600 °C for 2 - 3 h to obtain the ceramic microspheres coated with aluminum nitride.

4. The thermal insulation material containing mesoporous and vacuum microsphere materials according to claim 3, characterized in that, The weight ratio of the aluminum nitride powder, ethanol, and ceramic microspheres is (5 - 6):(100 - 120):

100.

5. A heat insulation material containing mesoporous and vacuum microsphere materials according to claim 2, characterized in that, The preparation method of the ceramic microspheres re-coated with SiO2 includes: dispersing the ceramic microspheres coated with aluminum nitride in ethanol, adding tetraethyl orthosilicate, and adjusting the pH = 9 - 10 with ammonia water, and stirring and reacting at 50 - 60 °C for 2 - 3 h to form ceramic microspheres re-coated with SiO2.

6. The thermal insulation material containing mesoporous and vacuum microsphere materials according to claim 5, characterized in that, The weight ratio of the ceramic microspheres coated with aluminum nitride, ethanol, and tetraethyl orthosilicate is 1:(10 - 12):(0.2 - 0.4).

7. An insulating material containing mesoporous and vacuum microsphere materials according to claim 2, characterized in that, The immersion temperature in the titanate coupling agent solution is 55 - 65 °C, and the immersion time is 1 - 2 h; the heat treatment temperature is 120 - 130 °C, and the heat treatment time is 1 - 2 h.

8. The thermal insulation material containing mesoporous and vacuum microsphere materials according to claim 2, characterized in that The preparation steps of the titanate coupling agent solution include: dissolving titanate coupling agent TCA-K38 in a mixed solution of ethanol and water, dropping acetic acid until the pH = 4 - 5, and hydrolyzing at 200 - 300 rpm for 30 - 40 min.

9. The thermal insulation material containing mesoporous and vacuum microsphere materials according to claim 8, wherein, The weight ratio of the ceramic microspheres re-coated with SiO2 and the titanate coupling agent solution is 100:1 - 2.

10. A method for preparing a thermal insulation material containing mesoporous and vacuum microsphere materials as described in any one of claims 1-9, characterized in that the steps It includes: Mix the fluorocarbon resin and the organosilicon-modified acrylic resin in proportion to obtain a resin matrix, add a dispersant, a defoamer, a leveling agent, a thickener, and nano-zirconia thereto, disperse at a high speed of 1800 - 2000 rpm for 30 - 40 min, add mica powder and modified hollow microspheres, and switch to stirring at 700 - 800 rpm for 15 - 25 min to obtain the product.

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