High-temperature-resistant thermal insulation material and preparation method thereof

Abstract

The application relates to the technical field of thermal insulation materials, and particularly discloses a high-temperature-resistant thermal insulation material and a preparation method thereof, and the high-temperature-resistant thermal insulation material comprises, from top to bottom, an aluminum foil fireproof cloth layer, an aerogel felt layer, an aluminum silicate thermal insulation cotton layer and an inorganic fiber layer, the aluminum foil fireproof cloth layer, the aerogel thermal insulation layer, the aluminum silicate thermal insulation cotton layer and the inorganic fiber layer are fixed by edge sewing through fireproof threads, the aluminum foil fireproof cloth layer comprises aluminum foil cloth and aluminum silicate ceramic cloth, and the aluminum foil cloth and the aluminum silicate ceramic cloth are bonded through a flame-retardant adhesive. The fireproof grade of the thermal insulation material obtained by the application can reach A1 level, the thermal conductivity coefficient is only 0.023 W / m.k at 1200 DEG C, the heat insulation property and the high-temperature resistance of the thermal insulation material are improved, the folding resistance of the application is up to 25931 times, the toughness is high, the thermal insulation material can be conveniently bent and connected, and the thermal insulation material can be customized according to equipment with different shapes.

Description

Technical Field

[0001] This application relates to the field of thermal insulation materials technology, and more specifically, to a high-temperature resistant thermal insulation material and its preparation method. Background Technology

[0002] Thermal insulation materials are materials that can impede heat transfer. They are widely used for pipeline insulation or protection of equipment such as shut-off valves and actuators, and are also known as flexible fireproof covers, thermal insulation covers, high-temperature resistant sleeves, and heat insulation jackets. When installed on pipelines for insulation, they effectively maintain the temperature inside the pipeline, reduce energy loss, improve energy utilization efficiency, and prevent strong external heat scattering. Thermal insulation materials can also be fixed to the surfaces of shut-off valves, actuators, and other equipment to isolate them from high temperatures and ignition sources, providing both insulation and flame retardancy, preventing damage to the equipment in high-temperature environments. Thermal insulation materials are relatively easy to install, removable, and easy to maintain, and are widely used in industrial production, construction, and energy fields.

[0003] In related technologies, high-temperature resistant fiber materials are usually added to the raw materials of thermal insulation materials to give the thermal insulation materials a certain degree of heat resistance. However, since the high-temperature resistant fiber materials have a micron-porous structure, their thermal insulation performance under high-temperature conditions is limited, and their high-temperature resistance is still poor, making it difficult to meet practical needs and unsuitable for thermal insulation and protection of equipment in high-temperature environments. Summary of the Invention

[0004] To improve the high-temperature resistance of thermal insulation materials, this application provides a high-temperature resistant thermal insulation material and its preparation method.

[0005] In a first aspect, this application provides a high-temperature resistant heat insulation material and its preparation method, which adopts the following technical solution: a high-temperature resistant heat insulation material, which comprises, from top to bottom, an aluminum foil fireproof cloth layer, an aerogel felt layer and an aluminum silicate heat insulation cotton layer, wherein the aluminum foil fireproof cloth layer, the aerogel heat insulation layer, the aluminum silicate heat insulation cotton layer and the inorganic fiber layer are sewn together with fireproof thread.

[0006] The fireproof aluminum foil fabric layer includes aluminum foil cloth and aluminum silicate ceramic cloth; the aluminum foil cloth and aluminum silicate ceramic cloth are bonded together by a flame-retardant adhesive.

[0007] Based on the weight of the aerogel felt layer, the aerogel felt layer comprises the following raw materials in parts by weight: 4-5 parts of glass fiber felt, 2-5 parts of silica aerogel, and 1-2 parts of acetone solution.

[0008] The aerogel felt layer material of this application can be selected from 4-5 parts of glass fiber felt, 2-5 parts of silica aerogel and 1-2 parts of acetone solution, and any value within the range of each can be selected, which can improve the high temperature resistance of the thermal insulation material.

[0009] By adopting the above technical solution, the thermal insulation material comprises, from top to bottom, an aluminum foil fireproof cloth layer, an aerogel felt layer, an aluminum silicate insulation cotton layer, and an inorganic fiber layer. The outermost layer uses a thicker aluminum foil fireproof cloth layer, which is aesthetically pleasing, scratch-resistant, and possesses strong mechanical properties. Furthermore, the aluminum foil fireproof cloth layer exhibits high thermal insulation properties, improving the high-temperature resistance of the insulation material. Moreover, the aluminum foil cloth also prevents the aerogel powder on the surface of the aerogel felt layer from falling off, ensuring the aerogel felt layer's excellent thermal insulation performance.

[0010] Aerogel felt layers are made by impregnating fiberglass felt with a silica aerogel solution. Fiberglass felt has good thermal insulation, fire resistance, and sound insulation properties, and the recycling of inorganic materials is environmentally friendly. Aerogel is an excellent thermal insulator, typically containing 98% air, and has high flame retardancy and high-temperature resistance. Impregnating fiberglass felt with a silica aerogel solution improves the poor toughness of the aerogel felt layer, making it easier to bend, and also enhances its high-temperature resistance. Aluminum silicate insulation cotton layers have high thermal insulation properties, acting as a barrier against both internal and external high temperatures, retaining heat in pipelines or preventing high-temperature damage to equipment, while also preventing aerogel powder from falling off during bending.

[0011] The thermal insulation material obtained by this application has a surface that is non-repellent to water and oil, and is moisture-proof, making it easy to clean and wipe. It also has good toughness, making it easy to bend and connect. Thermal insulation materials can be customized according to different shapes of equipment and are suitable for food, petrochemical, metallurgy, papermaking and power industries.

[0012] Preferably, the aluminum foil fireproof cloth layer is prepared by the following steps: a flame-retardant adhesive with a thickness of 2-4 mm is coated on the surface of the aluminum silicate ceramic cloth, and the aluminum foil cloth is bonded to the surface of the aluminum silicate ceramic cloth to obtain the aluminum foil fireproof cloth layer.

[0013] By adopting the above technical solution and adjusting the thickness of the flame-retardant adhesive coating on the aluminum silicate surface, the adhesion between the aluminum silicate ceramic cloth and the aluminum foil cloth in the aluminum foil fireproof cloth layer can be improved, thereby improving the high temperature resistance of the aluminum foil fireproof cloth layer. It also prevents the flame-retardant adhesive from being too thin, as this would result in poor adhesion between the aluminum foil cloth and the aluminum silicate ceramic cloth surface, making it easy to fall off. If it is too thick, it will reduce the drying speed of the adhesive and cause it to drip onto the edges of the foil cloth and the aluminum silicate ceramic cloth. Therefore, this application has controlled the thickness of the flame-retardant adhesive to 2-4 mm through multiple experiments.

[0014] Preferably, the flame-retardant adhesive comprises the following raw materials in parts by weight: 10-30 parts aluminum dihydrogen phosphate and 5-10 parts p-dichloromethylbenzene.

[0015] This application discloses a flame-retardant adhesive raw material that can be selected from 10-30 parts of aluminum dihydrogen phosphate and 5-10 parts of p-dichloromethylbenzene, with any value within the respective range, and can improve the high-temperature resistance of the thermal insulation material.

[0016] By employing the above technical solution, aluminum dihydrogen phosphate slowly releases water of crystallization when heated above 300°C, absorbing a large amount of heat energy and reducing the temperature of the combustion surface. The released water dilutes the oxygen in the air, inhibiting the combustion reaction, and ultimately produces boron oxide, which coats the surface of the ceramic fiber cloth, providing heat insulation and oxygen barrier properties. Adding p-methyldichlorobenzene in combination with aluminum dihydrogen phosphate can further enhance its flame-retardant effect.

[0017] Preferably, the weight ratio of p-methyldichlorobenzene to aluminum dihydrogen phosphate is 1:(2-5).

[0018] By adopting the above technical solution and adjusting the weight ratio of p-methyldichlorobenzene to aluminum dihydrogen phosphate, the flame retardancy of aluminum dihydrogen phosphate can be further improved, thereby further improving the flame retardancy of the aluminum foil fireproof cloth layer.

[0019] Preferably, the aerogel felt layer is prepared by the following steps:

[0020] Silica aerogel solution: Add silica aerogel to acetone solution and disperse by ultrasonication to obtain a silica aerogel solution with a mass concentration of 5-8%.

[0021] The glass fiber felt is immersed in a silica aerogel solution for 10-15 minutes and then supercritically dried to obtain an aerogel felt layer.

[0022] By adopting the above technical solution, silica aerogel is dissolved in acetone solution and then ultrasonically dispersed to obtain a silica aerogel solution with high dispersion uniformity. Glass fibers are then immersed in the silica aerogel solution to improve the toughness of the glass fibers, thereby improving the toughness of the aerogel felt layer.

[0023] Choosing acetone solution can improve the solubility of silica aerogel, thereby improving the dispersion stability of silica aerogel in silica aerogel solution. Controlling the mass concentration of silica aerogel solution can ensure the effect of glass fiber mat immersion in silica aerogel solution modification. Using supercritical drying can avoid the collapse of aerogel mat layer and prevent the aerogel mat layer from shrinking or being damaged.

[0024] Preferably, the mass ratio of the silica aerogel solution to the glass fiber mat is 1:(2.5-3.5).

[0025] By adopting the above technical solution and adjusting the mass ratio of silica aerogel liquid to glass fiber mat, it is beneficial for the silica aerogel solution to enter the interior of the glass fiber mat, which can further improve the heat insulation and fire resistance of the aerogel mat layer.

[0026] Preferably, the aerogel felt layer further includes the following raw material in parts by weight: 3-5 parts of methyltrimethoxysilane.

[0027] By adopting the above technical solution, methyltrimethylsilane is added as an adhesive to improve the adhesion of silica aerogel to the surface of glass fiber mat. On the other hand, methyltrimethylsilane can also keep the dried aerogel powder flexible and reduce the brittleness of the aerogel powder.

[0028] Secondly, this application provides a method for preparing a high-temperature resistant thermal insulation material, which is specifically achieved through the following technical solution:

[0029] A method for preparing a high-temperature resistant thermal insulation material includes the following steps:

[0030] Preparation of aluminum foil fireproof cloth layer and aerogel felt layer;

[0031] The aluminum foil fireproof cloth layer, aerogel insulation layer, and aluminum silicate insulation cotton layer are sewn together with fireproof thread.

[0032] By adopting the above technical solution, this application secures the aluminum foil fireproof cloth layer, aerogel insulation layer, and aluminum silicate insulation cotton layer with fire-resistant thread. The outermost layer uses a thicker aluminum foil fireproof cloth layer, which is aesthetically pleasing, scratch-resistant, and has strong mechanical properties, as well as high thermal insulation performance. The fiberglass felt has good toughness and excellent thermal insulation, high-temperature resistance, and sound insulation performance. The aluminum silicate insulation cotton layer has high thermal insulation properties, acting as a barrier against high internal and external temperatures of the equipment. These three layers work synergistically to give the insulation material high thermal insulation and high-temperature resistance. Furthermore, the fire-resistant thread used to secure the three layers—aluminum foil fireproof cloth layer, aerogel insulation layer, and aluminum silicate insulation cotton layer—is highly heat-resistant and fireproof, preventing the thread from burning through under high-temperature combustion conditions and causing the three layers to detach, effectively ensuring the insulation material's usability under high-temperature combustion conditions.

[0033] In summary, this application includes at least one of the following beneficial technical effects:

[0034] (1) This application improves the thermal insulation and high temperature resistance of the thermal insulation material by adjusting the weight ratio of p-methyldichlorobenzene and aluminum dihydrogen phosphate in the flame retardant adhesive during the preparation of the aluminum foil fireproof cloth layer, so that the thermal conductivity of the thermal insulation material at 1200℃ is 0.030-0.033W / mk.

[0035] (2) By controlling the thickness of the flame-retardant adhesive coating to 3mm when coating the surface of the aluminum silicate ceramic cloth, the thermal conductivity of the insulation material at 1200℃ is 0.029-0.030W / mk, which further improves the heat insulation and high temperature resistance of the insulation material.

[0036] (3) In the process of preparing the aerogel felt layer, this application adjusts the mass ratio of silica aerogel solution to glass fiber felt so that the thermal conductivity of the thermal insulation material at 1200℃ is 0.026-0.028W / mk, which further improves the thermal insulation and high temperature resistance of the thermal insulation material.

[0037] (4) This application improves the thermal insulation and high temperature resistance of the thermal insulation material by adding 0.8 kg of methyltrimethoxysilane after immersing the glass fiber felt in the silica aerogel solution.

[0038] (5) The heat insulation material obtained in this application uses aluminum foil fireproof cloth as the outer surface, so that the surface of the heat insulation material is not water-repellent, not oil-repellent, and not permeable to moisture, making it easier to clean and wipe. It also has good toughness and the folding resistance reaches up to 25,931 times, making it easy to bend and connect. The heat insulation material can be customized according to different shapes of equipment and is suitable for various fields such as food, petrochemical, metallurgy, papermaking and power. Detailed Implementation

[0039] The present application will be further described in detail below with reference to specific embodiments.

[0040] The following raw materials mentioned in this application are all commercially available products, intended to fully disclose the raw materials in this application, and should not be construed as limiting the source of the raw materials. Specifically:

[0041] The insulation layer consists of aluminum silicate insulation cotton with a fire resistance temperature of 1000-1300℃ and a compressive strength of 0.08-0.12MPa; aluminum foil cloth with a thickness of 0.5mm and a thermal conductivity of 0.036; aluminum silicate ceramic cloth with a thickness of 2-3mm and a compressive strength of 600MPa; glass fiber mat with an elongation at break of 3-4% and a diameter of 6-20mm; and silica aerogel with a particle size of 400 mesh, a specific surface area of ​​200, and a pH of 6. 5-7.5; Acetone solution, with an effective substance content of 99.5%, molecular weight of 58.08, and density of 0.788 g / cm3; Aluminum dihydrogen phosphate, with an effective substance content of 99%; p-dichloromethylbenzene, with an effective substance content of 98%; Methyltrimethoxysilane, with an effective substance content of 99%, gas emission of 0.1 mL / g, and pH 6-8; Fireproof thread, made of glass fiber sewing thread, with a thickness of 0.25 mm and model number frx-113.

[0042] The following are examples of the preparation of flame-retardant adhesives.

[0043] Preparation Example 1

[0044] The flame-retardant adhesive of Example 1 was prepared by the following steps:

[0045] According to the dosage in Table 1, aluminum dihydrogen phosphate and p-methyldichlorobenzene were mixed and stirred evenly to obtain a flame-retardant adhesive.

[0046] Preparation Examples 2-5

[0047] The flame-retardant adhesives prepared in Examples 2-5 differ from those prepared in Example 1 in that the amount of flame-retardant adhesive used is different, as detailed in Table 1.

[0048] Table 1. Dosage of each raw material in the flame-retardant adhesives prepared in Examples 1-5 (unit: kg)

[0049] raw material Preparation Example 1 Preparation Example 2 Preparation Example 3 Preparation Example 4 Preparation Example 5 Aluminum dihydrogen phosphate 10 10 30 25 30 p-Dichloromethylbenzene 10 5 10 5 5

[0050] Example 1

[0051] The high-temperature resistant thermal insulation material of Example 1 was prepared through the following steps:

[0052] Preparation of aluminum foil fireproof cloth layer: A flame-retardant adhesive with a thickness of 2 mm is coated on the surface of aluminum silicate ceramic cloth, and aluminum foil is bonded to the surface of aluminum silicate ceramic cloth to obtain aluminum foil fireproof cloth layer; wherein the flame-retardant adhesive is the flame-retardant adhesive prepared in Preparation Example 1.

[0053] Preparation of aerogel felt layer: Add silica aerogel to acetone solution and disperse by ultrasonication to obtain a silica aerogel solution with a mass concentration of 6%;

[0054] 4.5 kg of glass fiber mat was immersed in 2.25 L of silica aerogel solution for 15 min and then supercritically dried to obtain an aerogel mat layer.

[0055] The aluminum foil fireproof cloth layer, aerogel insulation layer, and aluminum silicate insulation cotton layer are sewn together with fireproof thread.

[0056] Examples 2-5

[0057] The difference between the high-temperature resistant heat insulation materials of Examples 2-5 and Example 1 is that when preparing the aluminum foil fireproof cloth layer, the flame-retardant adhesive prepared in Example 2-5 is used, and the rest of the operation is the same as in Example 1.

[0058] Examples 6-7

[0059] The difference between the high-temperature resistant heat insulation materials in Examples 6-7 and those in Example 3 is that the flame-retardant adhesive coating thickness is 3mm and 4mm respectively when preparing the aluminum foil fireproof cloth layer, while the other operations are the same as in Example 3.

[0060] Examples 8-11

[0061] The difference between the high-temperature resistant insulation materials in Examples 8-11 and those in Example 6 is that the amount of silica aerogel solution used in the preparation of the aerogel felt layer is 1.8L, 1.5L, 1.29L, and 1.13L, respectively. The other operations are the same as in Example 3.

[0062] Examples 12-14

[0063] The difference between the high-temperature resistant insulation materials of Examples 12-14 and Example 9 is that after immersing the glass fiber felt in the silica aerogel solution, 0.5 kg, 0.8 kg and 1 kg of methyltrimethoxysilane were added respectively, and the rest of the operation was the same as in Example 9.

[0064] Comparative Example 1

[0065] The difference between the high-temperature resistant insulation material of Comparative Example 1 and Example 1 is that the high-temperature resistant insulation material does not include an aluminum foil fireproof cloth layer, while the rest of the operation is the same as that of Example 1.

[0066] Comparative Example 2

[0067] The difference between the high-temperature resistant insulation material of Comparative Example 2 and Example 1 is that the high-temperature resistant insulation material does not include an aluminum silicate insulation cotton layer, while the rest of the operation is the same as that of Example 1.

[0068] Performance Testing (Part 1)

[0069] The performance of the thermal insulation materials obtained in different Examples 1-14 and Comparative Examples 1-2 was tested using the following testing standards or methods. The test results are detailed in Table 2.

[0070] Fire resistance performance: The fire resistance performance of the insulation material shall be tested in accordance with GB8624-2006.

[0071] Folding resistance: A folding test is conducted on the same part of the insulation material, with a folding frequency of 60-100 times / min and a folding angle of 120-150°. The number of folds before the insulation material breaks represents the folding resistance of the insulation material.

[0072] Thermal conductivity: The thermal conductivity of the insulation material at 1200℃ was tested in accordance with GB / T10294-2008.

[0073] Table 2 Performance test results of different thermal insulation materials

[0074]

[0075]

[0076] The test results in Table 2 show that the fire rating of the thermal insulation material obtained in this application can reach A1 level, and the thermal conductivity at 1200℃ is as low as 0.023W / mk, which improves the thermal insulation and high temperature resistance of the thermal insulation material. Moreover, the flexural strength of this application reaches up to 25931 times, which has high toughness and is convenient for bending and connection. Thermal insulation materials can be customized according to equipment of different shapes.

[0077] Based on the performance test data of the thermal insulation materials in Examples 1-5, it can be seen that the thermal conductivity of the thermal insulation materials obtained in Examples 2-4 at 1200℃ is 0.030-0.033W / mk, which is lower than that in Examples 1 and 5. This indicates that when the weight ratio of p-methyldichlorobenzene to aluminum dihydrogen phosphate in the flame retardant binder is 1:(2-5) during the preparation of the aluminum foil fireproof cloth layer, the thermal insulation and high temperature resistance of the thermal insulation material are improved. This may be related to the fact that the addition of p-methyldichlorobenzene and aluminum dihydrogen phosphate can further improve the flame retardant effect of aluminum dihydrogen phosphate.

[0078] Based on the performance test data of the thermal insulation materials in Examples 3 and 6-7, it can be seen that the thermal conductivity of the thermal insulation material obtained in Example 7 at 1200℃ is 0.029-0.030 W / mk, which is lower than that in Examples 3 and 7. This indicates that when a flame-retardant adhesive is coated on the surface of the aluminosilicate ceramic cloth with a thickness of 3 mm, the thermal insulation and high-temperature resistance of the thermal insulation material are improved. This may be related to the fact that adjusting the thickness of the flame-retardant adhesive coating on the aluminosilicate surface can improve the adhesion between the aluminosilicate ceramic cloth and the aluminum foil cloth in the aluminum foil fireproof cloth layer, thereby improving the high-temperature resistance of the aluminum foil fireproof cloth layer.

[0079] Based on the performance test data of the thermal insulation materials in Examples 6 and 8-11, it can be seen that the thermal conductivity of the thermal insulation materials obtained in Examples 8-10 at 1200℃ is 0.026-0.028 W / mk, which is lower than that in Examples 6 and 11. This indicates that when the mass ratio of silica aerogel solution to glass fiber felt is 1:(2.5-3.5) during the preparation of the aerogel felt layer, the thermal insulation and high temperature resistance of the thermal insulation material are improved. This may be related to the fact that adjusting the mass ratio of silica aerogel solution to glass fiber felt can further improve the thermal insulation and fire resistance of the aerogel felt layer.

[0080] Based on the performance test data of the thermal insulation materials in Examples 12-14, it can be seen that the thermal conductivity of the thermal insulation material obtained in Example 13 at 1200℃ is 0.023W / mk, which is lower than that in Examples 12 and 14. This indicates that when the glass fiber mat is immersed in the silica aerogel solution and 0.8kg of methyltrimethoxysilane is added, the thermal insulation and high temperature resistance of the thermal insulation material are improved. This may be because methyltrimethoxysilane acts as a binder, improving the adhesion of silica aerogel to the surface of glass fiber mat. On the other hand, methyltrimethoxysilane can also keep the dried aerogel powder flexible and reduce the brittleness of the aerogel powder.

[0081] Based on the performance test data of the insulation materials in Example 1 and Comparative Examples 1-2, it can be seen that the insulation material consists of an aluminum foil fireproof cloth layer, an aerogel felt layer, and an aluminum silicate insulation cotton layer from top to bottom. The design of the three layers improves the insulation performance and heat resistance of the insulation material to varying degrees.

[0082] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A high temperature resistant thermal insulation material, characterized in that, From top to bottom, it consists of an aluminum foil fireproof cloth layer, an aerogel felt layer, and an aluminum silicate heat insulation cotton layer, which are fixed together by fireproof thread. The fireproof aluminum foil fabric layer includes aluminum foil cloth and aluminum silicate ceramic cloth; the aluminum foil cloth and aluminum silicate ceramic cloth are bonded together with a flame-retardant adhesive. The aerogel felt layer comprises the following raw materials: glass fiber felt, silica aerogel, acetone solution, and methyltrimethoxysilane; The aerogel felt layer is prepared by the following steps: Silica aerogel solution: Add silica aerogel to acetone solution and disperse by ultrasonication to obtain a silica aerogel solution with a mass concentration of 5-8%. The glass fiber mat is immersed in a silica aerogel solution for 10-15 minutes and then supercritically dried to obtain an aerogel mat layer. The volume ratio of the silica aerogel solution to the mass ratio of the glass fiber mat is 1L:(2.5-3.5)kg; The aluminum foil fireproof cloth layer is prepared by the following steps: a flame-retardant adhesive is coated on the surface of the aluminum silicate ceramic cloth, the thickness of the flame-retardant adhesive is 2-4mm, and the aluminum foil is bonded to the surface of the aluminum silicate ceramic cloth to obtain the aluminum foil fireproof cloth layer. The flame-retardant adhesive comprises the following raw materials in parts by weight: 10-30 parts aluminum dihydrogen phosphate and 5-10 parts p-dichloromethylbenzene.

2. The high temperature resistant thermal insulation material according to claim 1, characterized in that, The weight ratio of p-dichloromethylbenzene to aluminum dihydrogen phosphate is 1:(2-5).

3. A method of producing the high-temperature-resistant thermal insulation material according to any one of claims 1 to 2, characterized in that The following steps are included: Preparation of aluminum foil fireproof cloth layer and aerogel felt layer; The aluminum foil fireproof cloth layer, aerogel felt layer, and aluminum silicate insulation cotton layer are sewn together with fireproof thread.

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