A composite aerogel insulation board and its preparation method and application

Abstract

The present application relates to the field of thermal insulation materials, and specifically discloses a composite aerogel thermal insulation board and its preparation method and application. The thermal insulation board includes a substrate and metal plates arranged on both sides of the substrate, and a composite aerogel felt is arranged between the substrate and the metal plate; the preparation method includes the following steps: the silica aerogel felt is immersed in a modified liquid, sprinkled with glass fiber, cured, and bonded and cured with a polyimide aerogel foam layer to obtain a composite aerogel felt; the composite aerogel felt is bonded and cured with the substrate by an adhesive, and the other side is bonded and cured with the metal plate by an adhesive to form a composite aerogel thermal insulation board. The present application also discloses the application of the above-mentioned thermal insulation board in the fields of building exterior wall insulation, cold chain logistics, pipeline insulation, and thermal protection of aerospace vehicles. The present application has the characteristics of improving the mechanical strength of the aerogel thermal insulation board, and obtaining a composite aerogel thermal insulation board with better thermal insulation and mechanical strength comprehensive performance.

Description

Technical Field

[0001] The present application relates to the technical field of thermal insulation materials. More specifically, it relates to a composite aerogel thermal insulation board, a preparation method thereof, and an application thereof. Background Art

[0002] At present, thermal insulation materials are widely used in the fields of architecture, transportation, aerospace, etc. Commonly used thermal insulation materials include organic materials such as polystyrene and polyurethane, and inorganic materials such as silicates and glass fibers. Although these traditional organic or inorganic thermal insulation materials have certain thermal insulation effects, they are insufficient in terms of thermal insulation performance and mechanical strength. The above defects limit the application of thermal insulation boards in a wider range of fields, especially in occasions with extremely high requirements for thermal insulation performance.

[0003] The structural characteristics of aerogel are a highly permeable cylindrical multi-branched nanoporous three-dimensional network structure with a porosity of more than 80%. It has an extremely high porosity and an extremely low density, and has an extremely low thermal conductivity, usually far lower than traditional thermal insulation materials such as polystyrene boards and glass wool. Therefore, it has excellent thermal insulation effects; and due to the chemical stability of the aerogel material in this application, while having good thermal insulation performance, the aerogel also has an ultra-light mass, reducing the construction load. Therefore, aerogel has broad application prospects in thermal insulation materials.

[0004] However, the mechanical properties of ordinary aerogel thermal insulation boards are poor, which limits their application and development. Therefore, preparing a composite aerogel thermal insulation board with better comprehensive performance of thermal insulation and mechanical strength is of great significance for the development and application fields of aerogel thermal insulation boards. Summary of the Invention

[0005] In order to improve the mechanical strength of aerogel thermal insulation boards and obtain a composite aerogel thermal insulation board with better comprehensive performance of thermal insulation and mechanical strength, the present application provides a composite aerogel thermal insulation board, a preparation method thereof, and an application thereof.

[0006] In a first aspect, the present application provides a composite aerogel thermal insulation board, adopting the following technical solution:

[0007] A composite aerogel thermal insulation board includes a substrate and metal plates arranged on both sides of the substrate. A composite aerogel felt is arranged between the substrate and the metal plates. The composite aerogel felt is prepared by the following method:

[0008] The silica aerogel felt is impregnated and dried in a modification liquid, then glass fibers are spread on it, and then a polyimide aerogel foam layer is bonded, and the polyimide aerogel foam layer is attached to the substrate, and the silica aerogel felt is attached to the metal plate;

[0009] Among them, the modification liquid mainly includes graphene oxide, PAMAM, carboxylated multi-walled carbon nanotubes, 1,3,5-triaminobenzene and genipin.

[0010] By adopting the above technical solution, the composite aerogel insulation board in the present application includes a substrate, a composite aerogel felt and a metal plate. This structural design not only enhances the overall strength of the insulation board, but also the metal plates on both sides of the substrate improve the heat reflection performance, which helps to further improve the heat insulation effect. More importantly, the composite aerogel felt in the present application includes a silica aerogel felt, a polyimide aerogel foam layer and glass fibers disposed therebetween. The polyimide aerogel is a three-dimensional porous material formed by cross-linking of polymer molecular chains. Compared with the silica inorganic aerogel with poor mechanical properties, the polyimide aerogel has characteristics such as low thermal conductivity and high specific surface area. Moreover, the polyimide aerogel has high mechanical properties, high thermal stability and extremely low thermal conductivity. Therefore, the composite gel felt in the present application selects the composite of the silica aerogel felt and the polyimide aerogel foam layer, which can achieve better heat insulation and mechanical properties, and the glass fibers scattered therebetween can play a certain strengthening role;

[0011] Moreover, in the present application, the glass fiber is located between the silica aerogel felt and the polyimide aerogel foam layer, and can form a needled structure with both, which is more conducive to improving the bonding strength between the two, thereby improving the stability and mechanical properties of the overall structure. In addition, the silica aerogel felt is first impregnated and treated in the modification liquid, and the addition of graphene oxide and carboxylated multi-walled carbon nanotubes in the modification liquid further plays a reinforcing role. More importantly, the silica aerogel surface contains silanol groups, the graphene oxide surface contains hydroxyl and carboxyl functional groups, and the addition of PAMAM (polyamide-amine dendrimer) enables the amino groups thereon to form chemical bonds with the hydroxyl groups on the silica aerogel surface, the carboxyl and hydroxyl groups on the graphene oxide surface, and the carboxyl oxygen-containing functional groups on the surface of the carboxylated multi-walled carbon nanotubes. With the addition of 1,3,5-triaminobenzene, the three amino groups and benzene ring structure on its molecular structure have strong intermolecular forces. The amino groups on its molecular structure and the amino groups in the PAMAM molecular structure can not only form covalent bonds with the hydroxyl and carboxyl groups on graphene oxide, carboxylated multi-walled carbon nanotubes, and silica aerogel, but also form covalent bonds with the hydroxyl groups in the glass fiber and the carboxyl and amide functional groups on the polyimide molecular chain. Together with genipin to achieve the connection between amino groups, a network connection structure is formed between the silica aerogel felt, the modification liquid, the glass fiber, and the polyimide aerogel foam layer. This not only helps to enhance the silica aerogel structure to form a more uniform and dense microscopic connection structure, but also helps to improve the overall mechanical strength and thermal stability of the composite aerogel felt, better maintain the network structure of the aerogel, prevent the decrease in heat insulation performance caused by thermal decomposition or thermal shrinkage, and the formed macromolecular network structure, in combination with the dispersion of carbon fiber and graphene oxide, significantly improves the mechanical properties of the overall composite aerogel felt.

[0012] Optionally, the modification liquid comprises the following raw materials in parts by weight:

[0013] 8 - 15 parts of polyvinyl alcohol, 5 - 10 parts of polyacrylamide, 30 - 40 parts of water, 10 - 20 parts of graphene oxide, 5 - 15 parts of PAMAM, 15 - 25 parts of carboxylated multi-walled carbon nanotubes, 3 - 8 parts of 1,3,5-triaminobenzene, 1 - 3 parts of genipin, 10 - 20 parts of ethanol, and 2 - 5 parts

[0014] sodium carboxymethyl cellulose.

[0015] By adopting the above technical solution, the addition of graphene oxide and carboxylated multi-walled carbon nanotubes plays a reinforcing role. The above-mentioned reinforcing fillers form a suspension in the solvent system, and the addition of sodium carboxymethyl cellulose prevents the settlement of the above-mentioned fillers in the solvent, so that they can be more uniformly loaded inside and on the surface of the silica aerogel felt during the impregnation process.

[0016] Optionally, when the silica aerogel felt is impregnated in the modification liquid, the impregnation temperature is 40 - 50 °C, the impregnation time is 40 - 60 min, and the impregnation pressure is 1.2 - 2.5 MPa.

[0017] By adopting the above technical solution, when the silica aerogel is impregnated in the modification liquid, applying a certain temperature and pressure is more conducive to forming a chemical connection between the modification liquid and the silica aerogel felt, realizing the modification treatment of the silica aerogel felt.

[0018] Optionally, the thickness of the silica aerogel felt is 3 - 5 mm, and the thickness of the polyimide aerogel foam layer is 1 - 2 mm.

[0019] By adopting the above technical solution, by controlling the thickness of the polyimide aerogel foam layer, while having a better heat insulation effect in cooperation with the silica aerogel felt, its mechanical properties are better.

[0020] Optionally, the polyimide aerogel foam layer is first impregnated and dried in the impregnation liquid and then compounded with the silica aerogel felt. The impregnation liquid includes the following raw materials in parts by weight: 5 - 10 parts of porous tin dioxide - wood ceramic powder composite particles, 2 - 5 parts of polyetheretherketone particles, 3 - 5 parts of sodium carboxymethyl cellulose, and 20 - 30 parts of water.

[0021] By adopting the above technical solution, the wood ceramic powder is obtained by modifying the silicon carbide ceramic precursor polycarbosilane with wood powder, and then compounded with porous tin dioxide to obtain composite particles. Utilizing the strong mechanical properties of silicon carbide ceramics and the fine porous structure of wood, it is loaded and added in porous tin dioxide. Moreover, porous tin dioxide also has excellent mechanical properties. Coupled with the high strength and high temperature resistance of polyetheretherketone Peek particles, when the polyimide aerogel foam is impregnated in the above impregnation liquid, the above composite particles and polyetheretherketone particles are loaded on the polyimide aerogel foam layer, significantly improving the mechanical properties of the foam layer, thereby significantly improving the mechanical properties of the composite aerogel felt layer. Finally, the prepared aerogel thermal insulation board has excellent heat insulation performance and excellent mechanical properties.

[0022] Optionally, the porous tin dioxide - wood ceramic powder composite particles are prepared by the following method:

[0023] The polycarbosilane and xylene are heated in a water bath at 70 - 85 °C, and after stirring, wood powder is added. Then, it is impregnated for 40 - 60 min under the condition of a vacuum degree of -0.09 - (-0.1). After the impregnation ends, porous tin dioxide is added and stirred. Then, the temperature is raised to 150 - 170 °C, and after heat preservation for 20 - 30 min, the temperature is raised to 230 - 250 °C. After heat preservation for 30 - 40 min, it is cooled to obtain the porous tin dioxide - wood ceramic powder composite particles.

[0024] By adopting the above technical solution, in this application, first, the polycarbosilane is impregnated with wood powder and xylene solvent under vacuum conditions, which helps the impregnation modification of polycarbosilane in wood powder, realizes the modification of polycarbosilane by wood powder. Then, porous tin dioxide is added and stirred. During the heating process, wood ceramic powder is gradually formed, and the xylene solvent gradually volatilizes. Continuing to heat, the carbonization of wood powder is further realized to form wood ceramic powder, and part of the wood ceramic powder is mutually loaded with porous tin dioxide. Utilizing the mechanical properties of metal oxides and the ceramic properties of the loaded wood ceramic powder part, it is found that the addition of the above composite particles can significantly improve the mechanical properties and can also improve the heat insulation performance to a certain extent.

[0025] Optionally, during the preparation process of the porous tin dioxide - wood ceramic powder composite particles, the addition amounts of each raw material are as follows: 10 - 20 parts of polycarbosilane, 15 - 25 parts of xylene, 10 - 20 parts of wood powder, and 12 - 20 parts of porous tin dioxide.

[0026] Optionally, the spreading amount of the glass fiber is 3 - 5 wt% of the mass of the silica aerogel felt.

[0027] Optionally, the base material comprises the following raw materials in parts by weight:

[0028] 40 - 60 parts of water, 80 - 120 parts of cement, 5 - 10 parts of silica aerogel powder, 5 - 8 parts of EVA emulsion, 3 - 8 parts of acrylate emulsion, 5 - 15 parts of expanded perlite, 20 - 30 parts of sand, 3 - 5 parts of glass fiber, 10 - 15 parts of limestone powder, and 0.3 - 0.5 part of water reducing agent.

[0029] By adopting the above technical solution, the base material in this application uses cement mortar as the main material, and acrylate emulsion and EVA emulsion are added to improve waterproofness and adhesion. The addition of glass fiber improves its crack resistance and mechanical properties, and finally, the prepared thermal insulation composite board has excellent performance in all aspects.

[0030] In the second aspect, this application provides a preparation method of a composite type aerogel thermal insulation board, adopting the following technical solution:

[0031] A preparation method of a composite type aerogel thermal insulation board, comprising the following steps:

[0032] S1. After impregnating the silica aerogel felt in the modification liquid, glass fibers are sprinkled, cured, and then bonded and cured with the polyimide aerogel foam layer to obtain a composite aerogel felt;

[0033] S2. The side of the polyimide aerogel foam layer of the composite aerogel felt is bonded and cured with the substrate through an adhesive, and the side of the silica aerogel felt of the composite aerogel felt is bonded and cured with the metal plate through an adhesive to form a composite aerogel thermal insulation board.

[0034] By adopting the above technical solution, the method provided by this application is simple, convenient and easy to realize industrialization.

[0035] In the third aspect, this application provides an application of a composite aerogel thermal insulation board, adopting the following technical solution: an application of a composite aerogel thermal insulation board in the fields of architecture and aerospace.

[0036] In summary, this application has the following beneficial effects:

[0037] 1. The composite aerogel felt in this application includes a silica aerogel felt, a polyimide aerogel foam layer, and glass fibers arranged therebetween, which can achieve better heat insulation and mechanical properties. Moreover, the glass fibers sprinkled between the two can play a certain strengthening role. In this application, the glass fibers are located between the silica aerogel felt and the polyimide aerogel foam layer, and can form a needling structure with the two, which is more conducive to improving the bonding strength between the two, thereby improving the stability and mechanical properties of the overall structure;

[0038] 2. The silica aerogel felt in this application is first soaked in the modification liquid. The addition of PAMAM and 1,3,5-triaminobenzene can form covalent bonds with the hydroxyl groups on the surface of the silica aerogel, the carboxyl and hydroxyl groups on the surface of graphene oxide, the hydroxyl groups in the glass fibers, and the carboxyl and amide functional groups on the polyimide molecular chain. Then, genipin is used to realize the connection between amino groups, so that a network connection structure is formed between the silica aerogel felt, the modification liquid, the glass fibers, and the polyimide aerogel foam layer. This not only helps to enhance the silica aerogel structure to form a more uniform and dense microscopic connection structure, but also helps to improve the overall mechanical strength and thermal stability of the composite aerogel felt, better maintain the network structure of the aerogel, prevent the decrease in heat insulation performance caused by thermal decomposition or thermal shrinkage, and the formed macromolecular network structure, combined with the dispersion of carbon fiber and graphene oxide, significantly improves the mechanical properties of the overall composite aerogel felt. Specific embodiments

[0039] The present application will be further described in detail below in conjunction with embodiments. It should be specifically noted that: for those conditions not specified in the following embodiments, they are carried out according to conventional conditions or conditions recommended by the manufacturer. Unless otherwise specified, the raw materials used in the following embodiments can be obtained from ordinary commercial sources.

[0040] In the following examples and preparation examples, the polyimide aerogel foam layer is obtained by cutting the polyimide PI ultra-short fiber aerogel foam board of Jiangxi Xiancai Nanofiber Technology Co., Ltd.;

[0041] The silica aerogel felt is selected from the silica aerogel felt of Guangdong Shuanghong Waterproof and Thermal Insulation Engineering Co., Ltd. with the brand of Shuanghong, and its thermal conductivity is 0.017 W / (m·K);

[0042] The carboxyl multi-walled carbon nanotubes are selected from the carboxyl multi-walled carbon nanotubes of Suzhou Kaifa New Materials Technology Co., Ltd. with the brand of BK and the model of CNT205;

[0043] The silica aerogel powder is selected from the silica aerogel particles of Yinhuang (Shanghai) Industrial Co., Ltd. with the brand of Cabot, the model of IC3100, and the particle size of 2 - 40 μm;

[0044] PAMAM is selected from PAMAM of Weihai Chenyuan New Materials Co., Ltd. with the product number of CYD-110A and 8 amino groups at the end;

[0045] The porous tin dioxide can be obtained by purchasing commercially available porous tin dioxide. In the present application, the porous tin dioxide is prepared by the following method:

[0046] Mix ethanol and water in a mass ratio of 1:8 to obtain a mixed solution, and then add tin tetrachloride pentahydrate and stir to dissolve to obtain a precursor solution. The mass concentration of tin tetrachloride pentahydrate in the mixed solution is 35 wt%;

[0047] Take the precursor solution and mix it with 0.5 mol / L sodium hydroxide solution and heat it to 50 °C. The volume ratio of the precursor solution to the sodium hydroxide solution is 1:1.5. Stir for 20 min and then keep it at a constant temperature and stand still. After aging for 25 h, crystals are obtained to form a precipitate. Filter, wash, and dry the precipitate to obtain a basic tin chloride precursor;

[0048] Calcine the obtained basic tin chloride precursor in an air atmosphere. The calcination temperature is 700 °C and the calcination time is 1.5 h, and then naturally cool it to room temperature to obtain porous tin dioxide.

[0049] The substrate in the present application can be adjusted according to the application scenario adaptability of the insulation board, and can be a gypsum board or a metal plate. For example, when applied to building insulation materials, a cement gypsum board can be selected.

[0050] The following preparation examples are for the preparation of porous tin dioxide-wood ceramic powder composite particles

[0051] Preparation Example 1

[0052] A method for preparing porous tin dioxide-wood ceramic powder composite particles, comprising the following steps:

[0053] 15 g of polycarbosilane (Mw = 1400, available from Henan Weitexi Chemical Technology Co., Ltd.) and 20 g of xylene were heated in a water bath at 80 °C, and after stirring, 15 g of wood powder (wood powder formed after cutting the board) was added. Then, it was impregnated at a vacuum degree of -0.05 for 50 min. After the impregnation was completed, 15 g of porous tin dioxide was added, and after stirring, the temperature was raised to 160 °C, held for 25 min, then raised to 240 °C, held for 35 min, and then cooled to obtain porous tin dioxide-wood ceramic powder composite particles.

[0054] Preparation Example 2

[0055] A method for preparing porous tin dioxide-wood ceramic powder composite particles, comprising the following steps:

[0056] 10 g of polycarbosilane (Mw = 1400, available from Henan Weitexi Chemical Technology Co., Ltd.) and 15 g of xylene were heated in a water bath at 70 °C, and after stirring, 10 g of wood powder (wood powder formed after cutting the board) was added. Then, it was impregnated at a vacuum degree of -0.09 for 60 min. After the impregnation was completed, 12 g of porous tin dioxide was added, and after stirring, the temperature was raised to 150 °C, held for 30 min, then raised to 230 °C, held for 40 min, and then cooled to obtain porous tin dioxide-wood ceramic powder composite particles.

[0057] Preparation Example 3

[0058] A method for preparing porous tin dioxide-wood ceramic powder composite particles, comprising the following steps:

[0059] 20 g of polycarbosilane (Mw = 1400, available from Henan Weitexi Chemical Technology Co., Ltd.) and 25 g of xylene were heated in a water bath at 85 °C, and after stirring, 20 g of wood powder (wood powder formed after cutting the board) was added. Then, it was impregnated at a vacuum degree of -0.1 for 40 min. After the impregnation was completed, 20 g of porous tin dioxide was added, and after stirring, the temperature was raised to 170 °C, held for 20 min, then raised to 250 °C, held for 30 min, and then cooled to obtain porous tin dioxide-wood ceramic powder composite particles.

[0060] Example 1

[0061] A method for preparing a composite aerogel thermal insulation board, comprising the following steps:

[0062] S1. Specifically, it includes the following steps:

[0063] S1-1. Mix 35 kg of water and 15 kg of ethanol, then add 4 kg of sodium carboxymethyl cellulose, add 6 kg of 1,3,5-triaminobenzene, stir, and then add 12 kg of polyvinyl alcohol, 8 kg of polyacrylamide, 15 kg of graphene oxide, 10 kg of PAMAM, 20 kg of carboxylated multi-walled carbon nanotubes, and 2 kg of genipin, and mix and stir to obtain a modified liquid.

[0064] S1-2. Immerse the silica aerogel felt with a thickness of 3 mm in the modified liquid. The immersion treatment temperature is 45 °C, the immersion time is 50 min, and the immersion pressure is 2.0 MPa. Then take out the immersed silica aerogel felt, sprinkle glass fiber on one side of the silica aerogel felt, and the glass fiber spreading amount is 4 wt% of the mass of the silica aerogel felt, and then perform drying and curing.

[0065] S1-3. Coat the side of the silica aerogel felt with glass fiber with an acrylate adhesive film, and then bond and cure it with a polyimide aerogel foam layer with a thickness of 1.5 mm to obtain a composite aerogel felt.

[0066] S2. Bond and cure the polyimide aerogel foam layer side of the composite aerogel felt to the substrate through an adhesive, and bond and cure the silica aerogel felt side of the composite aerogel felt to the metal plate through an adhesive to form a composite aerogel thermal insulation board. The adhesive in step S2 is selected as an acrylate self-adhesive.

[0067] Among them, the substrate in step S2 is prepared by the following method:

[0068] Mix 50 kg of water, 100 kg of cement, 8 kg of silica aerogel powder, 6 kg of EVA emulsion, 5 kg of acrylate emulsion, 10 kg of expanded perlite, 25 kg of sand, 4 kg of glass fiber, 12 kg of limestone powder, and 0.4 kg of water reducing agent evenly, then put them into a mold, press and cure to obtain the substrate.

[0069] Example 2

[0070] A preparation method of a composite aerogel thermal insulation board, including the following steps:

[0071] S1. Specifically, it includes the following steps:

[0072] S1-1. Mix 30 kg of water and 10 kg of ethanol, then add 2 kg of sodium carboxymethyl cellulose, add 3 kg of 1,3,5-triaminobenzene, stir, and then add 8 kg of polyvinyl alcohol, 5 kg of polyacrylamide, 10 kg of graphene oxide, 5 kg of PAMAM, 15 kg of carboxylated multi-walled carbon nanotubes, and 1 kg of genipin, and mix and stir to obtain a modified liquid.

[0073] S1-2. Immerse the silica aerogel felt with a thickness of 3 mm in the modification liquid. The immersion treatment temperature is 40 °C, the immersion time is 60 min, and the immersion pressure is 1.2 MPa. Then take out the immersed silica aerogel felt, and glass fibers are spread on one side of the silica aerogel felt. The spreading amount of glass fibers is 3 wt% of the mass of the silica aerogel felt, and then drying and curing are carried out;

[0074] S1-3. Coat the side of the silica aerogel felt with glass fibers with an acrylate adhesive film, and then bond and cure it with a polyimide aerogel foam layer with a thickness of 1 mm to obtain a composite aerogel felt;

[0075] S2. Bond and cure the side of the composite aerogel felt with the polyimide aerogel foam layer to the substrate through an adhesive, and bond and cure the side of the composite aerogel felt with the silica aerogel felt to the metal plate through an adhesive to form a composite aerogel insulation board. The adhesive in step S2 is selected as an acrylate self-adhesive.

[0076] The substrate in step S2 is prepared by the following method:

[0077] Mix 40 kg of water, 80 kg of cement, 5 kg of silica aerogel powder, 5 kg of EVA emulsion, 3 kg of acrylate emulsion, 5 kg of expanded perlite, 20 kg of sand, 3 kg of glass fibers, 10 kg of limestone powder and 0.3 kg of water reducing agent evenly, then put them into a mold, press and cure to obtain the substrate.

[0078] Example 3

[0079] A preparation method of a composite aerogel insulation board, comprising the following steps:

[0080] S1. Specifically, it includes the following steps:

[0081] S1-1. Mix 40 kg of water and 20 kg of ethanol, then add 5 kg of sodium carboxymethyl cellulose, add 8 kg of 1,3,5-triaminobenzene, stir and then add 15 kg of polyvinyl alcohol, 10 kg of polyacrylamide, 20 kg of graphene oxide, 15 kg of PAMAM, 25 kg of carboxylated multi-walled carbon nanotubes, 3 kg of genipin, and mix and stir to obtain a modification liquid;

[0082] S1-2. Immerse the silica aerogel felt with a thickness of 5 mm in the modification liquid. The immersion treatment temperature is 50 °C, the immersion time is 40 min, and the immersion pressure is 2.5 MPa. Then take out the immersed silica aerogel felt, and glass fibers are spread on one side of the silica aerogel felt. The spreading amount of glass fibers is 5 wt% of the mass of the silica aerogel felt, and then drying and curing are carried out;

[0083] S1-3. Coat the side of the silica aerogel felt sprinkled with glass fibers with an acrylate adhesive film, and then bond and cure it with a polyimide aerogel foam layer with a thickness of 2 mm to obtain a composite aerogel felt;

[0084] S2. Bond and cure the polyimide aerogel foam layer side of the composite aerogel felt to the substrate through an adhesive, and bond and cure the silica aerogel felt side of the composite aerogel felt to the metal plate through an adhesive to form a composite aerogel thermal insulation board, where the adhesive in step S2 is an acrylate self-adhesive.

[0085] The substrate in step S2 is prepared by the following method:

[0086] Mix 60 kg of water, 120 kg of cement, 10 kg of silica aerogel powder, 8 kg of EVA emulsion, 8 kg of acrylate emulsion, 15 kg of expanded perlite, 30 kg of sand, 5 kg of glass fiber, 15 kg of limestone powder and 0.5 kg of water reducing agent evenly, then put them into a mold, press and cure to obtain the substrate.

[0087] Example 4

[0088] A method for preparing a composite aerogel thermal insulation board is carried out according to the method in Example 1, the difference is that in step S1-2, when the silica aerogel felt is impregnated in the modification liquid, it is carried out under normal pressure.

[0089] Example 5

[0090] A method for preparing a composite aerogel thermal insulation board is carried out according to the method in Example 1, the difference is that the polyimide aerogel foam layer in step S1-3 is first impregnated in the impregnation liquid, then dried and then bonded and cured with the side of the silica aerogel felt sprinkled with glass fibers according to the steps in step S1-3. Among them, the impregnation liquid is prepared by mixing 8 kg of the porous tin dioxide-wood ceramic powder composite particles prepared in Preparation Example 1, 3 kg of polyether ether ketone particles, 4 kg of sodium carboxymethyl cellulose and 25 kg of water, and the impregnation liquid submerges the polyimide aerogel foam layer.

[0091] Example 6

[0092] A preparation method of a composite aerogel thermal insulation board is carried out according to the method in Example 1, except that the polyimide aerogel foam layer in step S1-3 is first impregnated in the impregnating solution, then dried and then bonded and cured with the side of the silica aerogel felt coated with glass fiber according to the steps in step S1-3. Among them, the impregnating solution is prepared by mixing 5 kg of the porous tin dioxide-wood ceramic powder composite particles prepared in Preparation Example 2, 2 kg of polyether ether ketone particles, 3 kg of sodium carboxymethyl cellulose and 20 kg of water, and the impregnating solution submerges the polyimide aerogel foam layer.

[0093] Example 7

[0094] A preparation method of a composite aerogel thermal insulation board is carried out according to the method in Example 1, except that the polyimide aerogel foam layer in step S1-3 is first impregnated in the impregnating solution, then dried and then bonded and cured with the side of the silica aerogel felt coated with glass fiber according to the steps in step S1-3. Among them, the impregnating solution is prepared by mixing 10 kg of the porous tin dioxide-wood ceramic powder composite particles prepared in Preparation Example 3, 5 kg of polyether ether ketone particles, 5 kg of sodium carboxymethyl cellulose and 30 kg of water, and the impregnating solution submerges the polyimide aerogel foam layer.

[0095] Example 8

[0096] A preparation method of a composite aerogel thermal insulation board is carried out according to the method in Example 5, except that polyether ether ketone particles are not added to the impregnating solution.

[0097] Example 9

[0098] A preparation method of a composite aerogel thermal insulation board is carried out according to the method in Example 5, except that the addition amount of polyether ether ketone particles in the impregnating solution is 7 kg.

[0099] Example 10

[0100] A preparation method of a composite aerogel thermal insulation board is carried out according to the method in Example 5, except that the porous tin dioxide-wood ceramic powder composite particles are not added to the impregnating solution.

[0101] Example 11

[0102] A preparation method of a composite aerogel thermal insulation board is carried out according to the method in Example 5, except that the porous tin dioxide-wood ceramic powder composite particles in the impregnating solution are equivalently replaced with porous tin dioxide.

[0103] Example 12

[0104] A preparation method of a composite aerogel thermal insulation board is carried out according to the method in Example 5, except that the porous tin dioxide-wood ceramic powder composite particles in the impregnating solution are used to replace the tin dioxide powder in equal amount.

[0105] Comparative Example 1

[0106] A preparation method of a composite aerogel thermal insulation board is carried out according to the method in Example 1, except that the treatment of steps S1-3 is not carried out. The silica aerogel with glass fiber spread on it is directly subjected to the operation in step S2. The side with glass fiber spread on it is directly bonded and cured with the substrate through an adhesive, and the other side is directly bonded and cured with the metal plate through an adhesive.

[0107] Comparative Example 2

[0108] A preparation method of a composite aerogel thermal insulation board is carried out according to the method in Example 1, except that in steps S1-2, no glass fiber is spread, and the operation in step S1-3 is directly carried out to bond and cure with the polyimide aerogel foam layer.

[0109] Comparative Example 3

[0110] A preparation method of a composite aerogel thermal insulation board is carried out according to the method in Example 1, except that the silica aerogel in steps S1-2 is not impregnated in the modification liquid, and after directly coating acrylate glue and spreading glass fiber, the operation in step S1-3 is directly carried out to bond and fix with the polyimide aerogel foam layer to obtain a composite aerogel felt.

[0111] Comparative Example 4

[0112] A preparation method of a composite aerogel thermal insulation board is carried out according to the method in Example 1, except that 1,3,5-triaminobenzene is not added to the modification liquid in step S1-1.

[0113] Comparative Example 5

[0114] A preparation method of a composite aerogel thermal insulation board is carried out according to the method in Example 1, except that PAMAM is not added to the modification liquid in step S1-1.

[0115] Comparative Example 6

[0116] A preparation method of a composite aerogel thermal insulation board is carried out according to the method in Example 1, except that genipin is not added to the modification liquid in step S1-1.

[0117] Performance detection

[0118] The thermal conductivity, compressive strength and flexural strength of the composite board after the composite aerogel felt and the cement gypsum substrate are bonded and fixed in step S1 of the present application embodiment and the comparative example are tested, and the test results are shown in Table 1 below:

[0119] Table 1:

[0120]

[0121]

[0122] Referring to the test results in Table 1 above, the thermal conductivity of the silica aerogel felt in the embodiment of the present application is 0.017W / (m·K), the compressive strength is 15MPa, and the flexural strength is 10MPa. Referring to the test results in Examples 1-3, it can be seen that when the composite board in Examples 1-3 of the present application is made of silica aerogel felt impregnated in a modified liquid and compounded with a polyimide aerogel foam layer, its thermal conductivity is further reduced, and it has better thermal insulation performance, and the compressive strength and flexural strength are significantly improved, and it has better mechanical properties. Combined with the test results of Example 4, when Example 4 is impregnated under normal pressure, its thermal insulation performance is slightly reduced, but its compressive strength and flexural strength are significantly reduced, and the mechanical properties are significantly reduced, which affects the formation of a cross-linked structure network in the composite structure.

[0123] Referring to the test results of Examples 5-7, when the polyimide aerogel foam layer is impregnated with the impregnation liquid, not only the thermal insulation performance is further reduced, but also the mechanical properties are further improved. Referring to the test results of Examples 8 and 9, when no polyetheretherketone is added to the impregnation liquid in Example 8, its thermal conductivity is slightly improved compared with that in Example 5, and the mechanical properties are significantly reduced. When the amount of polyetheretherketone added in Example 9 is too much, its thermal conductivity is improved, and the mechanical properties are limited. Referring to Example 10, when no porous tin dioxide-wood ceramic powder composite particles are added, the thermal conductivity is significantly improved compared with Example 5, the thermal insulation performance is reduced, and the mechanical properties are significantly reduced. The addition of metal elements significantly improves the mechanical properties. When the composite particles are replaced with porous tin dioxide in Example 11, its mechanical properties are reduced. The addition of metal elements improves the mechanical properties, but the porous structure reduces the mechanical properties. Combined with the test results in Example 12, when tin dioxide powder is added, its mechanical properties are better, but both the mechanical properties and thermal insulation properties are weaker than those in Example 5.

[0124] ​Referring to the test results of Example 1 and Comparative Example 1, the thermal insulation performance and mechanical properties of the aerogel felt obtained by not compounding the polyimide aerogel foam layer on the silica aerogel in Comparative Example 1 are much lower than the comprehensive performance of the composite board in Example 1. Combining with the test results of Comparative Example 2, when glass fibers are not spread between the silica aerogel felt and the polyimide aerogel in Comparative Example 2, the mechanical properties of the composite board are also significantly reduced. When the silica aerogel in Comparative Example 3 is directly compounded with the polyimide aerogel foam layer without being impregnated and modified with the modification liquid, its mechanical properties are also significantly weaker than those in Example 1. When the silica aerogel felt and the polyimide aerogel foam layer are directly compounded without modification treatment in this application, although the thermal insulation performance is improved, the mechanical properties are weak. Referring again to the test results of Example 1 and Comparative Examples 4-6, it can be seen that when 1,3,5-triaminobenzene, PAMAM or genipin is not added to the modification liquid, the mechanical properties of the composite board are significantly reduced, and the thermal insulation performance is also reduced. The main reason is that the formation of a cross-linked structure can reduce the performance degradation problems caused by heat loss or thermal shrinkage.

[0125] Finally, the composite aerogel thermal insulation board prepared in this application has excellent thermal insulation performance and better mechanical properties. In the construction field, especially for thermal insulation materials in walls, roofs, floors, etc., a lower thermal conductivity is required to reduce heat transfer and improve the energy efficiency of buildings. Or in refrigeration and freezing equipment, using materials with low thermal conductivity can reduce energy loss and improve the efficiency of the equipment, and it has better application performance. Finally, the composite aerogel thermal insulation board prepared in this application has better application effects in high-efficiency heat insulation and preservation occasions such as building exterior wall insulation, cold chain logistics, pipeline insulation, and thermal protection of aerospace vehicles.

[0126] This specific embodiment is only an interpretation of this application and does not limit this application. Those skilled in the art can make modifications without creative contributions to this embodiment according to needs after reading this specification, but as long as they are within the scope of the claims of this application, they are protected by the patent law.

Claims

1. A composite aerogel insulation board, characterized in that: The invention comprises a substrate and metal plates arranged on both sides of the substrate, wherein a composite aerogel felt is arranged between the substrate and the metal plates, and the composite aerogel felt is prepared by the following method: The silica aerogel felt is immersed in a modified liquid, dried, and then sprinkled with glass fiber, and then bonded with a polyimide aerogel foam layer, wherein the polyimide aerogel foam layer is bonded to a substrate, and the silica aerogel felt is bonded to a metal plate; Wherein, the modified liquid comprises the following raw materials in parts by weight: 8-15 parts of polyvinyl alcohol, 5-10 parts of polyacrylamide, 30-40 parts of water, 10-20 parts of graphene oxide, 5-15 parts of PAMAM, 15-25 parts of carboxylated multi-walled carbon nanotubes, 3-8 parts of 1,3,5-triaminobenzene, 1-3 parts of genipin, 10-20 parts of ethanol and 2-5 parts of sodium carboxymethylcellulose; The polyimide aerogel foam layer is firstly immersed in an impregnation liquid, dried, and then composited with the silica aerogel felt. The impregnation liquid includes the following raw materials in parts by weight: 5-10 parts of porous tin dioxide-wood ceramic powder composite particles, 2-5 parts of polyetheretherketone particles, 3-5 parts of sodium carboxymethyl cellulose and 20-30 parts of water.

2. A composite aerogel insulation board according to claim 1, characterized in that: When the silica aerogel felt is immersed in the modified liquid, the immersion temperature is 40-50° C., the immersion time is 40-60 min, and the immersion pressure is 1.2-2.5 MPa.

3. The composite aerogel insulation board according to claim 1, characterized in that: The thickness of the silica aerogel felt is 3-5 mm, and the thickness of the polyimide aerogel foam layer is 1-2 mm.

4. The composite aerogel insulation board according to claim 1, characterized in that: The porous tin dioxide-wood ceramic powder composite particles are prepared by the following method: Heat polycarbosilane and xylene in a water bath at 70-85°C, add wood powder after stirring, and then impregnate for 40-60 minutes under vacuum conditions of -0.09-(-0.1). After the impregnation, add porous tin dioxide, stir, and then heat to 150-170°C, keep warm for 20-30 minutes, then heat to 230-250°C, keep warm for 30-40 minutes and then cool to obtain porous tin dioxide-wood ceramic powder composite particles.

5. The composite aerogel insulation board according to claim 4, characterized in that: During the preparation of porous tin dioxide-wood ceramic powder composite particles, the amount of each raw material added is as follows: 10-20 parts of polycarbosilane, 15-25 parts of xylene, 10-20 parts of wood flour, 12-20 parts of porous tin dioxide.

6. The composite aerogel insulation board according to claim 1, characterized in that: The spreading amount of the glass fiber is 3-5wt% of the mass of the silica aerogel felt.

7. A method for preparing a composite aerogel insulation board according to any one of claims 1 to 6, characterized in that: The following steps are involved: S1, after the silica aerogel felt is immersed in a modified liquid, it is sprinkled with glass fiber, solidified, and then bonded and solidified with a polyimide aerogel foam layer to obtain a composite aerogel felt; S2. The polyimide aerogel foam layer side of the composite aerogel felt is bonded and cured with the substrate by adhesive, and the silica aerogel felt side of the composite aerogel felt is bonded and cured with the metal plate by adhesive to form a composite aerogel insulation board.

8. Application of the composite aerogel insulation board as claimed in any one of claims 1 to 6 in the fields of building exterior wall insulation, cold chain logistics, pipeline insulation and aerospace thermal protection.

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