Foaming thermal insulation material and preparation method thereof

Abstract

The invention provides a foaming thermal insulation material and a preparation method thereof.The foaming thermal insulation material is composed of Portland cement, a waterborne polyurethane emulsion, a dispersing agent, an aerogel compound, filler and water, the aerogel compound is composed of composite fibers and inorganic multi-component aerogel, and the size specification and interface performance of the composite fibers are designed, so that the thermal insulation performance of the composite fibers is improved; according to the preparation method, inorganic polybasic aerogel is adopted as a raw material, the stability of the inorganic polybasic aerogel is optimized, a three-dimensional nano-fiber three-dimensional net-shaped framework can be introduced into a silicate gel system in the preparation process of the foaming thermal insulation material, the pore enrichment degree in the silicate gel system is improved, and the framework is attached to the surface of filler, so that the radiation stroke of heat is remarkably improved, and the radiation heat transfer effect is reduced; the heat conductivity coefficient of the foaming thermal insulation material is obviously reduced, the thermal insulation performance and combustion performance grade of the foaming thermal insulation material are obviously improved, and the foaming thermal insulation material has the advantages of wide application prospect and convenience in popularization and implementation.

Description

Technical Field

[0001] This application belongs to the technical field of building materials, and specifically relates to a foamed thermal insulation material and a preparation method thereof. Background Art

[0002] In the prior art, with the intensification of the global energy crisis and the continuous improvement of people's awareness of environmental protection, building energy conservation has become an important link in achieving sustainable development. Among building energy consumption, the heat transfer of envelope structures such as walls and roofs accounts for a relatively large proportion. Therefore, the research and application of high-efficiency thermal insulation materials are of great significance for reducing building energy consumption and improving energy utilization efficiency. Foamed thermal insulation materials for buildings have been widely used in the field of building energy conservation due to their excellent thermal insulation performance, light weight and high strength, etc.

[0003] In the prior art, the building materials commonly used in the construction field mainly include polystyrene foam (EPS), extruded polystyrene foam (XPS), and polyurethane foam (PU). In the actual application process, on the one hand, although organic foamed materials are poor conductors of heat and have excellent thermal insulation performance, their flame retardant performance is generally poor, there are relatively large fire safety hazards, and they are likely to produce a large amount of toxic smoke in a fire, threatening the lives of people and the environment; on the other hand, the mechanical properties of traditional organic foamed thermal insulation materials are poor, and their compressive, impact-resistant, and tensile properties are generally low, making it difficult to be used as the supporting structure of the building main body, and mostly used as the filling structure between buildings. In addition, the existing foamed thermal insulation materials also have problems such as complex construction processes and weak connection performance with each component during the construction process, significantly affecting the overall performance and service life of the building thermal insulation system.

[0004] Therefore, developing a building foamed thermal insulation material that not only has excellent thermal insulation performance, can replace the existing organic foamed materials, but also has excellent mechanical strength and construction convenience has become an urgent technical problem to be solved in the current building energy conservation field. Summary of the Invention

[0005] This application aims to solve the technical problems in the prior art that traditional building foamed materials are mostly organic foamed materials. On the one hand, their flame retardant performance is poor, and a large amount of toxic smoke will be generated in case of a fire, there are relatively large fire safety hazards during the actual use process. On the other hand, their compressive performance, impact-resistant performance, tensile performance, and connection performance are low. After using them as the wall structure of the building, the overall service life of the building is low, and the fire risk coefficient is high, and proposes a foamed thermal insulation material.

[0006] To solve the technical problems proposed by this application, this application also provides a preparation method of a foamed thermal insulation material;

[0007] To solve the technical problems proposed in this application, the present application also provides an application of a foamed thermal insulation material.

[0008] The present application adopts the following scheme. A foamed thermal insulation material is composed of the following components by weight: 41 parts - 55 parts of portland cement, 8 parts - 16 parts of waterborne polyurethane emulsion, 2 parts - 8 parts of dispersant, 23 parts - 34 parts of aerogel composite, 20 parts - 33 parts of filler, and 12 parts - 25 parts of water.

[0009] Among them, by weight of the total amount of the aerogel composite, it is composed of the following components: 5 parts - 8 parts of fiber A, 5 parts - 8 parts of fiber B, and 12 parts - 18 parts of inorganic multi-component aerogel.

[0010] Among them, the inorganic multi-component aerogel contains rare earth metal oxides.

[0011] Among them, the average length of fiber A is greater than that of fiber B.

[0012] Among them, both fiber A and fiber B are surface-modified.

[0013] In some possible embodiments, the inorganic multi-component aerogel is Al 2 O 3 -Y 2 O 3 -SiO 2 ternary aerogel.

[0014] In some possible embodiments, the preparation method of the Al 2 O 3 -Y 2 O 3 -SiO 2 ternary aerogel includes the following steps:

[0015] Step 101. Add tetraethyl orthosilicate, aluminum chloride hexahydrate, yttrium chloride hexahydrate, deionized water, and absolute ethanol into a stirring kettle in a molar ratio of 1:(6.5 - 8.1):(2.2 - 3.1):5:9. React for 60 min - 120 min under the conditions of a nitrogen atmosphere, a water bath at 10°C - 25°C, and 2800 rpm - 3200 rpm to obtain a precursor solution.

[0016] Step 102. Passivate the precursor solution prepared in Step 101 for 15 min - 20 min under the conditions of -5°C - 0°C. Then, continue to add propylene oxide into the reaction kettle at a stirring frequency of 200 rpm. Stop adding propylene oxide when no more gelation substances are produced in the reaction kettle to obtain a crude ternary aerogel.

[0017] Step 103. After aging the ternary aerogel crude product prepared in Step 102 at room temperature for 24 h - 48 h, transfer the aged ternary aerogel crude product to a displacement dish containing absolute ethanol. After displacing the moisture in the ternary aerogel crude product, transfer the ternary aerogel crude product to an ethanol supercritical drying device for drying, and then the Al 2 O 3 -Y 2 O 3 -SiO 2 ternary aerogel is obtained.

[0018] In the actual implementation process, in Step 103, the working parameters of the ethanol supercritical drying device are: 270 °C, 9 MPa - 9.5 MPa, and heat preservation and pressure maintenance for 2 h.

[0019] In the actual implementation process, an aerogel composite is introduced into the silicate gel system, and the aerogel composite is composed of carbon fiber, glass fiber, and Al 2 O 3 -Y 2 O 3 -SiO 2 ternary aerogel. By designing the size specifications and surface properties of the carbon fiber and glass fiber, the connection performance of the glass fiber, glass fiber, and Al 2 O 3 -Y 2 O 3 -SiO 2 ternary aerogel is improved. Among them, Al 2 O 3 -Y 2 O 3 -SiO 2 ternary aerogel has a three-dimensional nano-network structure. During the preparation process of the foaming material, the surface-modified glass fiber and carbon fiber and Al 2 O 3 -Y 2 O 3 -SiO 2 ternary aerogel are tightly connected through C-Si bonds, Si-O-Si bonds, and van der Waals forces, and then a three-dimensional nano-fiber three-dimensional network structure (as shown in Figure 1 ) is introduced into the silicate gel system, effectively increasing the radiation travel of heat, reducing the radiation heat transfer effect, and then significantly reducing the thermal conductivity of the foaming thermal insulation material and significantly improving the thermal insulation performance of the foaming thermal insulation material.

[0020] In Al 2 O 3 -Y 2 O 3 -SiO 2During the preparation process of the ternary aerogel, by introducing Y, on the one hand, taking advantage of the inherent properties of rare earth metals, further reducing Al 2 O 3 -Y 2 O 3 -SiO 2 the radiative heat transfer of the ternary aerogel, on the other hand, Y inhibits the polymorphic transformation of Al 2 O 3 -Y 2 O 3 -SiO 2 during the preparation process of the ternary aerogel, improves the structural stability of Al 2 O 3 -Y 2 O 3 -SiO 2 O 3 -SiO 2 from collapsing during the preparation process of the ternary aerogel, and effectively avoids the collapse of Al 2 O 3 -Y 2 O 3 -SiO 2 from occurring during the preparation process of the ternary aerogel, and thus facilitates the preparation of the Al 2 O 3 -Y 2 O 3 -SiO 2 ternary aerogel into an aerogel fiber composite, and finally introduces a three-dimensional nano-fiber three-dimensional network structure into the silicate gel system to significantly reduce the thermal conductivity of the foamed thermal insulation material and significantly improve the thermal insulation performance of the foamed thermal insulation material.

[0021] In some possible embodiments,

[0022] Al 2 O 3 -Y 2 O 3 -SiO 2 the specific surface area of the ternary aerogel is 680 m 2 / g - 710 m 2 / g;

[0023] Al 2 O 3 -Y 2 O 3 -SiO 2 the pore volume of the ternary aerogel is 4.7 cm 3 / g - 5.2 cm 3 / g;

[0024] Al 2 O 3 -Y2 O 3 -SiO 2 The average pore size of the ternary aerogel is 15 nm - 20 nm.

[0025] In some possible embodiments, fiber A is selected as glass fiber, fiber B is selected as carbon fiber, the length range of fiber A is 12 mm - 15 mm, the length range of fiber B is 3 mm - 5 mm, the aspect ratio of fiber A is (8 - 11):1, and the aspect ratio of fiber B is (12 - 15):1.

[0026] In some possible embodiments,

[0027] The surface modification of fiber A and / or fiber B includes the following steps:

[0028] Step 201. Fiber A and / or fiber B, silane coupling agent A, silane coupling agent B, absolute ethanol, and deionized water are sequentially added to a stirring kettle according to a mass ratio of 1:(3 - 5):(3 - 5):5:15, and reacted at 25°C and 800 rpm - 1200 rpm for 4 h - 8 h. During the reaction process, an acetic acid solution is dropped into the reaction kettle to maintain the reaction system at pH = 5. After the reaction is completed, a crude composite fiber is obtained;

[0029] Step 202. After filtering the liquid phase in the crude composite fiber, the solid phase is retained, and then the solid phase is washed with absolute ethanol, washed with deionized water, and dried to obtain fiber A and / or fiber B with surface modification. The fiber A after surface modification is defined as fiber A1, and the fiber B after surface modification is defined as fiber B1.

[0030] In some possible embodiments, in step 201, the silane coupling agent A is selected as KH550, and the silane coupling agent B is selected as KH792.

[0031] In the actual implementation process, the surface - modified glass fiber and carbon fiber will react with Al 2 O 3 -Y 2 O 3 -SiO 2 The ternary aerogel is tightly connected through C - Si bonds, Si - O - Si bonds, and van der Waals forces, thereby introducing a three - dimensional nano - fiber three - dimensional network structure into the silicate gel system (as shown in Figure 1 ), increasing the radiation travel of heat, reducing the radiation heat transfer effect, and thus significantly reducing the thermal conductivity of the foamed thermal insulation material and significantly improving the thermal insulation performance of the foamed thermal insulation material.

[0032] In some possible embodiments, the preparation method of the aerogel composite includes the following steps:

[0033] Put fiber A1, fiber B1, and Al 2 O 3 -Y 2 O 3 -SiO 2 The ternary aerogel, aqueous polyurethane emulsion, and deionized water are put into a stirring kettle and stirred and dispersed for 90 min - 120 min under the conditions of room temperature, nitrogen atmosphere, -0.01 MPa, and 1500 rpm - 2200 rpm to obtain the aerogel composite.

[0034] In some possible embodiments, the fiber A1, fiber B1, and Al 2 O 3 -Y 2 O 3 -SiO 2 The mass ratio of the ternary aerogel, aqueous polyurethane emulsion, and deionized water is: 1:1:(5.5 - 8.3):(3.6 - 6.5):12.

[0035] In some possible embodiments, by weight of the total amount of fillers, it consists of the following components: hollow glass microspheres, coal ash powder, basalt, and marble.

[0036] In some possible embodiments, the filler is composed of a mixture of hollow glass microspheres, coal ash powder, basalt, and marble in a mass ratio of 5.4:8.1:15.2:18.5.

[0037] In some possible embodiments, the particle size of the hollow glass beads is 0.05 mm - 0.1 mm, the particle size of the coal ash powder is 0.01 mm - 0.03 mm, the particle size of the basalt is 5 mm - 8 mm, and the particle size of the marble is 15 mm - 25 mm.

[0038] To solve the technical problems proposed by this application, this application also provides a preparation method of a foamed thermal insulation material, including the following steps:

[0039] Ingredient preparation: Weigh each component according to the preset target ratio for standby

[0040] First slurry adjustment: Put 1 / 2 weight portion of portland cement, 1 / 2 weight portion of aqueous polyurethane emulsion, 2 / 3 weight portion of filler, and an appropriate amount of water into a mixer and stir for 10 min under the conditions of room temperature and a stirring frequency of 1800 rpm to obtain slurry A;

[0041] Second slurry adjustment: Put the remaining portland cement, the remaining aqueous polyurethane emulsion, the remaining filler, the aerogel composite, a dispersant, and the remaining water into a mixer and stir for 20 min under the conditions of room temperature and a stirring frequency of 1800 rpm to obtain slurry B;

[0042] Finished product mixing: Before use, sequentially put slurry A and slurry B into a blender, and stir for 15 minutes at 50°C with a stirring frequency of 1200 rpm to obtain the finished foam insulation material.

[0043] To solve the technical problems proposed by this application, this application also provides an application of a foam insulation material, which is used to prepare a thermal insulation wall for buildings.

[0044] Compared with the prior art, this application has the following beneficial effects:

[0045] This application provides a foam insulation material, its preparation method and its application. The foam insulation material is composed of Portland cement, waterborne polyurethane emulsion, dispersant, aerogel composite, filler and water. Among them, the aerogel composite is composed of composite fibers and inorganic multi-component aerogels. By designing the size specifications and interfacial properties of the composite fibers and optimizing the stability of the inorganic multi-component aerogels, during the preparation process of the foam insulation material, a three-dimensional nano-fiber three-dimensional network skeleton can be introduced into the silicate gel system, improving the pore enrichment degree in the silicate gel system. This skeleton can adhere to the surface of the filler, significantly increasing the radiation travel of heat, reducing the radiation heat transfer effect, significantly reducing the thermal conductivity of the foam insulation material, significantly improving the thermal insulation performance and combustion performance grade of the foam insulation material. After using it as a building thermal insulation wall, it can not only effectively avoid the loss of indoor temperature, but also effectively improve the building fire safety coefficient. It has the advantages of wide application prospects and being easy to promote and implement. Description of the Drawings

[0046] Figure 1 is the SEM image of the foam insulation material prepared in Example 2 of this application;

[0047] Figure 2 is the bar chart of the thermal conductivity of the foam insulation materials prepared in Examples 1-3 and Comparative Examples 1-5 of this application. Detailed Embodiments

[0048] Combined with Figure 1-2 Examples 1-3 and the content shown in Comparative Examples 1-5 are used to further illustrate the technical solutions provided by this application.

[0049] Among them, fiber A is selected as glass fiber, fiber B is selected as carbon fiber, the average length of fiber A is 13.4 mm, the average length of fiber B is 3.8 mm, the aspect ratio of fiber A is 10:1, and the aspect ratio of fiber B is 12:1.

[0050] Among them, the filler is composed of hollow glass microspheres, coal ash powder, basalt, and marble mixed in a mass ratio of 5.4:8.1:15.2:18.5.

[0051] Among them, the average particle size of the hollow glass beads is 0.07 mm, the average particle size of the coal ash powder is 0.03 mm, the average particle size of the basalt is 8 mm, and the average particle size of the marble is 21 mm.

[0052] Example 1

[0053] (1) Al 2 O 3 -Y 2 O 3 -SiO 2 The preparation of the ternary aerogel includes the following steps:

[0054] Step 101. Tetraethyl orthosilicate, aluminum chloride hexahydrate, yttrium chloride hexahydrate, deionized water, and absolute ethanol were successively added to a stirring kettle according to a molar ratio of 1:6.5:2.2:5:9. After reacting for 65 min under the conditions of a nitrogen atmosphere, a water bath at 15°C, and 2,800 rpm, a precursor solution was obtained.

[0055] Step 102. After passivating the precursor solution prepared in Step 101 for 15 min at -5°C, propylene oxide was continuously added to the reaction kettle under the condition of a stirring frequency of 200 rpm. When no more gelled substances were produced in the reaction kettle, the addition of propylene oxide was stopped, and a crude ternary aerogel was obtained.

[0056] Step 103. After aging the crude ternary aerogel prepared in Step 102 at room temperature for 24 h, the aged crude ternary aerogel was transferred to a displacement dish containing absolute ethanol. After replacing the water in the crude ternary aerogel, the crude ternary aerogel was transferred to an ethanol supercritical drying device and dried under the conditions of 270°C, 9.2 MPa, and heat preservation and pressure maintenance for 2 h, and the Al 2 O 3 -Y 2 O 3 -SiO 2 ternary aerogel was obtained.

[0057] Among them, the median specific surface area of the Al 2 O 3 -Y 2 O 3 -SiO 2 ternary aerogel is 683.7 m 2 / g;

[0058] Al 2 O 3 -Y 2 O 3 -SiO 2 The median pore volume of the ternary aerogel is 4.8 cm 3 / g;

[0059] Al 2 O 3 -Y 2 O 3 -SiO 2 The average pore size of the ternary aerogel is 17 nm.

[0060] (2) The surface modification of fiber A and / or fiber B includes the following steps:

[0061] Step 201. Add fiber A and / or fiber B, silane coupling agent KH550, silane coupling agent KH792, absolute ethanol, and deionized water into a stirring kettle in sequence according to the mass ratio of 1:3:3:5:15, and react for 4 h at 25 °C and 800 rpm. During the reaction process, dropwise add acetic acid solution into the reaction kettle to maintain the reaction system at pH = 5. After the reaction is completed, the crude composite fiber is obtained.

[0062] Step 202. After filtering the liquid phase in the crude composite fiber, retain the solid phase, and then wash the solid phase successively with absolute ethanol, deionized water, and dry it to obtain fiber A and / or fiber B with surface modification. Define the fiber A with surface modification as fiber A1, and define the fiber B with surface modification as fiber B1.

[0063] (3) The preparation method of the aerogel composite includes the following steps:

[0064] Add fiber A1, fiber B1, Al 2 O 3 -Y 2 O 3 -SiO 2 ternary aerogel, aqueous polyurethane emulsion, and deionized water into a stirring kettle in sequence according to the mass ratio of 1:1:5.5:3.6:12, and stir and disperse for 90 min at room temperature, in a nitrogen atmosphere, -0.01 MPa, and 1500 rpm to obtain the aerogel composite.

[0065] (4) The preparation method of the foamed thermal insulation material includes the following steps:

[0066] Step 301. Batching: Weigh each component according to the preset target ratio for standby

[0067] First slurry preparation: Put 1 / 2 weight part of portland cement, 1 / 2 weight part of aqueous polyurethane emulsion, 2 / 3 weight part of filler, and an appropriate amount of water into a mixer, and stir for 10 min at room temperature and a stirring frequency of 1800 rpm to obtain slurry A.

[0068] Step 302. Secondary sizing: Put the remaining portland cement, the remaining aqueous polyurethane emulsion, the remaining filler, the aerogel composite, the dispersant, and the remaining water into a blender, and stir for 20 min at room temperature with a stirring frequency of 1800 rpm to obtain sizing B.

[0069] Step 303. Finished product mixing: Before use, put sizing A and sizing B into a blender in sequence, and stir for 15 min at 50 °C with a stirring frequency of 1200 rpm to obtain the finished foamed thermal insulation material.

[0070] Example 2

[0071] (1) Al 2 O 3 -Y 2 O 3 -SiO 2 The preparation of the ternary aerogel includes the following steps:

[0072] Step 101. Put tetraethyl orthosilicate, aluminum chloride hexahydrate, yttrium chloride hexahydrate, deionized water, and absolute ethanol into a stirring kettle in a molar ratio of 1:7.5:2.6:5:9, and react for 60 min - 120 min at 16 °C in a nitrogen atmosphere with a water bath and 3000 rpm to obtain the precursor solution.

[0073] Step 102. Passivate the precursor solution prepared in Step 101 at -5 °C - 0 °C for 18 min, and continue to add propylene oxide to the reaction kettle at a stirring frequency of 200 rpm. Stop adding propylene oxide when no more gelified substances are produced in the reaction kettle to obtain the crude ternary aerogel.

[0074] Step 103. Age the crude ternary aerogel prepared in Step 102 at room temperature for 36 h, transfer the aged crude ternary aerogel to a replacement dish containing absolute ethanol, replace the water in the crude ternary aerogel, and then transfer the crude ternary aerogel to an ethanol supercritical drying device to dry it at 270 °C and 9.2 MPa for 2 h under heat preservation and pressure maintenance to obtain the Al 2 O 3 -Y 2 O 3 -SiO 2 ternary aerogel.

[0075] Among them, the median specific surface area of the Al 2 O 3 -Y 2 O 3 -SiO 2 ternary aerogel is 689.9 m 2 / g;

[0076] Al 2 O 3 -Y 2 O 3 -SiO 2 The median pore volume of the ternary aerogel is 4.9 cm 3 / g;

[0077] Al 2 O 3 -Y 2 O 3 -SiO 2 The average pore size of the ternary aerogel is 16 nm.

[0078] (2) The surface modification of fiber A and / or fiber B comprises the following steps:

[0079] Step 201. Add fiber A and / or fiber B, silane coupling agent KH550, silane coupling agent KH792, anhydrous ethanol, and deionized water in a mass ratio of 1:4:4:5:15 to a stirring kettle, and react at 25° C. and 1050 rpm for 6 hours. During the reaction, add acetic acid solution dropwise to the reactor to maintain the reaction system at pH=5. After the reaction is completed, a crude composite fiber product is obtained;

[0080] Step 202. After filtering the liquid phase in the composite fiber crude product, retain the solid phase, and then wash the solid phase with anhydrous ethanol, deionized water, and dry it in sequence to obtain surface-modified fiber A and / or fiber B, and define the surface-modified fiber A as fiber A1, and define the surface-modified fiber B as fiber B1.

[0081] (3) The method for preparing the aerogel composite comprises the following steps:

[0082] Fiber A1, fiber B1, Al 2 O 3 -Y 2 O 3 -SiO 2 The ternary aerogel, aqueous polyurethane emulsion and deionized water were sequentially put into a stirring kettle in a mass ratio of 1:1:7.5:5.2:12, and stirred and dispersed for 100 minutes at room temperature, nitrogen atmosphere, -0.01 MPa, and 1800 rpm to obtain an aerogel composite.

[0083] (4) The preparation method of the foamed thermal insulation material comprises the following steps:

[0084] Step 301. Ingredients: weigh each component according to the preset target ratio and set aside

[0085] Primary sizing: Prepare 1 / 2 part by weight of Portland cement, 1 / 2 part by weight of waterborne polyurethane emulsion, 2 / 3 part by weight of filler and appropriate amount of water, put them into a blender, and stir for 10 min at room temperature with a stirring frequency of 1800 rpm to obtain sizing A;

[0086] Step 302. Secondary sizing: Prepare the remaining Portland cement, the remaining waterborne polyurethane emulsion, the remaining filler, aerogel composite, dispersant and the remaining water, put them into a blender, and stir for 20 min at room temperature with a stirring frequency of 1800 rpm to obtain sizing B;

[0087] Step 303. Finished product mixing: Before use, put sizing A and sizing B into a blender in sequence, and stir for 15 min at 50 °C with a stirring frequency of 1200 rpm to obtain the finished foamed thermal insulation material.

[0088] Example 3

[0089] (1) Al 2 O 3 -Y 2 O 3 -SiO 2 The preparation of the ternary aerogel includes the following steps:

[0090] Step 101. Put tetraethyl orthosilicate, aluminum chloride hexahydrate, yttrium chloride hexahydrate, deionized water and absolute ethanol into a stirring kettle in a molar ratio of 1:8.1:3.1:5:9, and react for 120 min in a nitrogen atmosphere at a water bath temperature of 15 °C and 3200 rpm to obtain a precursor solution;

[0091] Step 102. Passivate the precursor solution prepared in Step 101 at -5 °C to 0 °C for 20 min, and then continue to add propylene oxide to the reaction kettle at a stirring frequency of 200 rpm. Stop adding propylene oxide when no more gelled substances are produced in the reaction kettle to obtain the ternary aerogel crude product;

[0092] Step 103. Age the ternary aerogel crude product prepared in Step 102 at room temperature for 48 h, transfer the aged ternary aerogel crude product to a displacement dish containing absolute ethanol, displace the water in the ternary aerogel crude product, and then transfer the ternary aerogel crude product to an ethanol supercritical drying equipment and dry it at 270 °C and 9.2 MPa for 2 h under heat preservation and pressure maintenance conditions to obtain the Al 2 O 3 -Y 2 O 3 -SiO 2 ternary aerogel.

[0093] Among them, Al 2 O3 -Y 2 O 3 -SiO 2 The median specific surface area of the ternary aerogel is 707.5 m 2 / g;

[0094] Al 2 O 3 -Y 2 O 3 -SiO 2 The median pore volume of the ternary aerogel is 5.2 cm 3 / g;

[0095] Al 2 O 3 -Y 2 O 3 -SiO 2 The average pore diameter of the ternary aerogel is 19 nm.

[0096] (2) The surface modification of fiber A and / or fiber B includes the following steps:

[0097] Step 201. Fiber A and / or fiber B, silane coupling agent KH550, silane coupling agent KH792, absolute ethanol, and deionized water are sequentially added to a stirring kettle according to a mass ratio of 1:5:5:5:15, and reacted at 25°C and 1200 rpm for 8 h. During the reaction, an acetic acid solution is added dropwise to the reaction kettle to maintain the reaction system at pH = 5. After the reaction is completed, a crude composite fiber is obtained;

[0098] Step 202. After filtering the liquid phase in the crude composite fiber, the solid phase is retained, and then the solid phase is washed successively with absolute ethanol, deionized water, and dried to obtain fiber A and / or fiber B with surface modification. The fiber A with surface modification is defined as fiber A1, and the fiber B with surface modification is defined as fiber B1.

[0099] (3) The preparation method of the aerogel composite includes the following steps:

[0100] Fiber A1, fiber B1, Al 2 O 3 -Y 2 O 3 -SiO 2 The ternary aerogel, aqueous polyurethane emulsion, and deionized water are sequentially added to a stirring kettle according to a mass ratio of 1:1:8.3:6.5:12, and stirred and dispersed for 120 min at room temperature, in a nitrogen atmosphere, at -0.01 MPa, and 2200 rpm to obtain the aerogel composite.

[0101] (4) The preparation method of the foamed thermal insulation material includes the following steps:

[0102] Step 301. Batching: Weigh each component according to the preset target ratio for standby.

[0103] Primary slurry preparation: Put 1 / 2 part by weight of portland cement, 1 / 2 part by weight of waterborne polyurethane emulsion, 2 / 3 part by weight of filler and an appropriate amount of water into a blender. Stir for 10 min at room temperature with a stirring frequency of 1800 rpm to obtain Slurry A.

[0104] Step 302. Secondary slurry preparation: Put the remaining portland cement, the remaining waterborne polyurethane emulsion, the remaining filler, aerogel composite, dispersant and the remaining water into a blender. Stir for 20 min at room temperature with a stirring frequency of 1800 rpm to obtain Slurry B.

[0105] Step 303. Finished product mixing: Before use, put Slurry A and Slurry B into a blender in sequence. Stir for 15 min at 50 °C with a stirring frequency of 1200 rpm to obtain the finished foam thermal insulation material.

[0106] Comparative Example 1

[0107] The difference between Comparative Example 1 and Example 2 is that after completely removing the aerogel composite, it is supplemented with portland cement and filler, and the remaining components and process steps remain unchanged.

[0108] Comparative Example 2

[0109] The difference between Comparative Example 2 and Example 2 is that after completely removing the inorganic multi-aerogel in the aerogel composite, it is supplemented with filler, and the remaining components and process steps remain unchanged.

[0110] Comparative Example 3

[0111] The difference between Comparative Example 3 and Example 2 is that after completely removing Fiber A (glass fiber) in the aerogel composite, it is supplemented with filler, and the remaining components and process steps remain unchanged.

[0112] Comparative Example 4

[0113] The difference between Comparative Example 4 and Example 2 is that after completely removing Fiber B (carbon fiber) in the aerogel composite, it is supplemented with filler, and the remaining components and process steps remain unchanged.

[0114] Comparative Example 5

[0115] The difference between Comparative Example 5 and Example 2 is that after completely removing the aerogel composite, it is supplemented with polystyrene (EPS), and the remaining components and process steps remain unchanged.

[0116] Table 1 Component Table of Examples 1-3 and Comparative Examples 1-5

[0117]

[0118] Continued Table 1

[0119]

[0120] The finished foamed materials prepared in Examples 1-3 and Comparative Examples 1-5 were subjected to the following tests:

[0121] Test 1: Referring to the provisions of the building industry standard JC / T 2200-2013 "Cement-based Foam Thermal Insulation Board", after the finished foamed materials prepared in Examples 1-3 and Comparative Examples 1-5 were made into corresponding test pieces through a specified mold, the compressive strength of the test pieces was tested;

[0122] Test 2: Referring to the provisions of the building industry standard JG T266-2011 "Foamed Concrete", after the finished foamed materials prepared in Examples 1-3 and Comparative Examples 1-5 were made into corresponding test pieces through a specified mold, the tensile strength of the test pieces was tested;

[0123] Test 3: Use a Tci thermal conductivity measuring instrument to test the thermal conductivity [mW / (m·K)] of the test samples. It is carried out in accordance with the ISO22007-2.2 standard. The test method is the transient plane heat source method (TPS). Under normal temperature and pressure conditions, 3 parallel samples are tested for each sample, and the results are averaged. The smaller the thermal conductivity, the better the thermal insulation performance;

[0124] Test 4: Referring to the provisions of GB 8624-2021 "Classification Standard for the Combustion Performance of Building Materials and Products", after the finished foamed materials prepared in Examples 1-3 and Comparative Examples 1-5 were made into corresponding test pieces through a specified mold, the combustion performance grade of the test pieces was tested. The test results are shown in Table 2 below.

[0125] Table 2 Test Results of Examples 1-3 and Comparative Examples 1-5

[0126] Test item Example 1 Example 2 Example 3 Comparative example 1 Compressive strength (MPa) 7.7 8.1 7.9 3.5 Tensile strength (kPa) 142.5 147.3 144.1 57.7 Thermal conductivity [mW / (m·K)] 20.5 19.3 20.9 47.4 Combustion performance level Grade A Grade A Grade A Grade A

[0127] Continued Table 2

[0128] Test item Comparative example 2 Comparative example 3 Comparative example 4 Comparative example 5 Compressive strength (MPa) 6.1 4.7 4.2 3.3 Tensile strength (kPa) 136.4 92.5 83.8 76.9 Thermal conductivity [mW / (m·K)] 41.3 27.5 29.3 34.1 Combustion performance level Grade A Grade A Grade A Grade B2

[0129] From Figure 1-2 and Table 2, it can be seen that in Examples 1-3, an aerogel composite was introduced into the silicate gel system, and the aerogel composite consisted of carbon fiber, glass fiber, Al 2 O 3 -Y 2 O3 -SiO 2 Ternary aerogel composition, by designing the size specifications and surface properties of carbon fiber and glass fiber, the connection performance of glass fiber, glass fiber and Al 2 O 3 -Y 2 O 3 -SiO 2 among the three ternary aerogels is improved, where Al 2 O 3 -Y 2 O 3 -SiO 2 The ternary aerogel is a three-dimensional nano-network structure. During the preparation process of the foaming material, the surface-modified glass fiber, carbon fiber and Al 2 O 3 -Y 2 O 3 -SiO 2 The ternary aerogel is tightly connected through C-Si bonds, Si-O-Si bonds and van der Waals forces, and then a three-dimensional nano-fiber three-dimensional network structure is introduced into the silicate gel system (as Figure 1 shown), which increases the radiation travel of heat, reduces the radiative heat transfer effect, and then significantly reduces the thermal conductivity of the foamed thermal insulation material and significantly improves the thermal insulation performance of the foamed thermal insulation material.

[0130] In the preparation process of Al 2 O 3 -Y 2 O 3 -SiO 2 ternary aerogel, by introducing Y, on the one hand, using the self-characteristics of rare earth metals, further reduces the radiative heat transfer of Al 2 O 3 -Y 2 O 3 -SiO 2 ternary aerogel, and inhibits the polymorphic transformation of Al 2 O 3 -Y 2 O 3 -SiO 2 ternary aerogel during the preparation process, and improves the structural stability of Al 2 O 3 -Y 2 O 3 -Y 2 O 3 -SiO 2 ternary aerogel, effectively avoiding the polymorphic transformation of Al 2 O 3 -Y 2 O 3 -SiO2 The ternary aerogel collapses during the preparation process, thus facilitating the introduction of Al 2 O 3 -Y 2 O 3 -SiO 2 The ternary aerogel is prepared into an aerogel fiber composite, and finally a three-dimensional nano-fiber three-dimensional network structure is introduced into the silicate gel system to significantly reduce the thermal conductivity of the foamed thermal insulation material and significantly improve the thermal insulation performance of the foamed thermal insulation material.

[0131] In Comparative Example 1, all the aerogel composites were removed. On the one hand, no composite fibers were introduced into the silicate gel system, and only the silicate cement and fillers served as the main mechanical structure of the foaming material. The connection performance between the silicate cement and the fillers was significantly reduced, and the mechanical properties of the foaming material were significantly reduced. On the other hand, no Al 2 O 3 -Y 2 O 3 -SiO 2 ternary aerogel was introduced into the silicate gel system, resulting in a lack of a three-dimensional nano-network structure. The radiation path of heat was shortened, the radiation heat transfer effect was enhanced, the thermal conductivity of the foamed thermal insulation material was significantly increased, and the thermal insulation performance of the foamed thermal insulation material was significantly reduced.

[0132] In Comparative Example 2, all the inorganic multi-component aerogels in the aerogel composite were removed. Although the mechanical properties of the silicate gel system were improved due to the introduction of composite fibers, no Al 2 O 3 -Y 2 O 3 -SiO 2 ternary aerogel was introduced into the silicate gel system, resulting in a lack of a three-dimensional nano-network structure. The radiation path of heat was shortened, the radiation heat transfer effect was enhanced, the thermal conductivity of the foamed thermal insulation material was significantly increased, and the thermal insulation performance of the foamed thermal insulation material was significantly reduced.

[0133] In Comparative Examples 3 / 4, all of Fiber A (glass fiber) / Fiber B (carbon fiber) in the aerogel composite were removed. After the foamed thermal insulation material changed from composite fibers to single fibers, the thermal conductivity of the foamed material increased to some extent, and the thermal insulation performance decreased to some extent. It can be seen that Al 2 O 3 -Y 2 O 3 -SiO 2The ternary aerogel has poor synergy with single fibers. By introducing fibers with different lengths, different materials, and different aspect ratios, during the modification process of composite fibers, a fiber helical structure will be introduced into the silicate gel system. The van der Waals force between the composite fibers drives the fibers to generate self-helix, thereby enhancing the enrichment degree of nano-pores in the silicate gel system, increasing the radiation travel of heat, and reducing the radiative heat transfer effect.

[0134] In Comparative Example 5, after completely removing the aerogel composite and using polystyrene (EPS) to make up for it, on the one hand, an organic foaming material is introduced into the silicate gel system. The connection performance between the organic foaming material and the silicate cement is low, which leads to a significant reduction in the mechanical properties of the foaming material. On the other hand, although the thermal insulation performance of the silicate foamed thermal insulation material can be slightly improved by introducing the organic foaming material, the combustion performance will also be significantly reduced, and the technical problems proposed in this application cannot be solved.

[0135] This application provides a foamed thermal insulation material, its preparation method, and its application. The foamed thermal insulation material is composed of silicate cement, waterborne polyurethane emulsion, dispersant, aerogel composite, filler, and water. Among them, the aerogel composite is composed of composite fibers and inorganic multi-component aerogel. By designing the size specifications and interfacial properties of the composite fibers and optimizing the stability of the inorganic multi-component aerogel, during the preparation process of the foamed thermal insulation material, a three-dimensional nano-fiber three-dimensional network skeleton can be introduced into the silicate gel system, enhancing the pore enrichment degree in the silicate gel system. This skeleton can adhere to the surface of the filler, significantly increasing the radiation travel of heat, reducing the radiative heat transfer effect, significantly reducing the thermal conductivity of the foamed thermal insulation material, significantly improving the thermal insulation performance and combustion performance grade of the foamed thermal insulation material. After using it as a building thermal insulation wall, it can not only effectively avoid the loss of indoor temperature but also effectively improve the overall safety factor of the building. It has the advantages of wide application prospects and being convenient for popularization and implementation.

[0136] The above are only the embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A foaming thermal insulation material, characterized in that: The composition is composed of the following components by weight: 41-55 parts of silicate cement, 8-16 parts of waterborne polyurethane emulsion, 2-8 parts of dispersant, 23-34 parts of aerogel composite, 20-33 parts of filler and 12-25 parts of water; Wherein, the aerogel composite is composed of the following components by weight of the total amount: 5-8 parts of fiber A, 5-8 parts of fiber B, and 12-18 parts of inorganic multi-element aerogel; Among them, inorganic polyaerogels contain rare earth metal oxides; Among them, the average length of fiber A is greater than the average length of fiber B; Wherein, both fiber A and fiber B are subjected to surface modification treatment.

2. A foamed thermal insulation material according to claim 1, characterized in that: The inorganic multi-component aerogel is Al2O3-Y2O3-SiO2 ternary aerogel.

3. A foamed thermal insulation material according to claim 2, characterized in that: The preparation method of Al2O3-Y2O3-SiO2 ternary aerogel comprises the following steps: Step 101. Put tetraethyl orthosilicate, aluminum chloride hexahydrate, yttrium chloride hexahydrate, deionized water and anhydrous ethanol into a stirring kettle in sequence, and react for 60 min to 120 min in a water bath at 10° C. to 25° C. and 2800 rpm to 3200 rpm in a nitrogen atmosphere to obtain a precursor liquid; Step 102. After the precursor liquid prepared in step 101 is passivated at -5°C-0°C for 15min-20min, propylene oxide is continuously added to the reactor under a stirring frequency of 200rpm. When gelled substances are no longer produced in the reactor, the addition of propylene oxide is stopped to obtain a crude ternary aerogel; Step 103. After aging the crude ternary aerogel product prepared in step 102 at room temperature for 24h-48h, the aged crude ternary aerogel product is transferred to a replacement dish containing anhydrous ethanol to replace the water in the crude ternary aerogel product. The crude ternary aerogel product is then transferred to an ethanol supercritical drying device for drying to obtain Al2O3-Y2O3-SiO2 ternary aerogel.

4. A foamed thermal insulation material according to claim 2, characterized in that: The specific surface area of ​​Al2O3-Y2O3-SiO2 ternary aerogel is 680m 2 / g-710m 2 / g; The pore volume of Al2O3-Y2O3-SiO2 ternary aerogel is 4.7 cm 3 / g-5.2cm 3 / g; The average pore size of Al2O3-Y2O3-SiO2 ternary aerogel is 15nm-20nm.

5. The foamed thermal insulation material according to claim 1, characterized in that: Fiber A is glass fiber, fiber B is carbon fiber, the length of fiber A is in the range of 12mm-15mm, the length of fiber B is in the range of 3mm-5mm, the aspect ratio of fiber A is (8-11):1, and the aspect ratio of fiber B is (12-15):

1.

6. The foamed thermal insulation material according to claim 1, characterized in that: The surface modification of fiber A and / or fiber B comprises the following steps: Step 201. Add fiber A and / or fiber B, silane coupling agent A, silane coupling agent B, anhydrous ethanol, and deionized water to a stirring kettle in sequence, and react at 25° C. and 800 rpm-1200 rpm for 4 h-8 h. During the reaction, add acetic acid solution dropwise to the reaction kettle to maintain the reaction system at pH=5. After the reaction is completed, a crude composite fiber product is obtained; Step 202. After filtering the liquid phase in the composite fiber crude product, retain the solid phase, and wash the solid phase with anhydrous ethanol, deionized water, and dry it in sequence to obtain surface-modified fiber A and / or fiber B, and define the surface-modified fiber A as fiber A1, and define the surface-modified fiber B as fiber B1.

7. A foamed thermal insulation material according to claim 6, characterized in that: In step 201, the silane coupling agent A is KH550, and the silane coupling agent B is KH792.

8. The foamed thermal insulation material according to claim 6, characterized in that: The method for preparing the aerogel composite comprises the following steps: Fiber A1, fiber B1, Al2O3-Y2O3-SiO2 ternary aerogel, aqueous polyurethane emulsion and deionized water are put into a stirring kettle, and stirred and dispersed for 90min-120min at room temperature, nitrogen atmosphere, -0.01MPa, 1500rpm-2200rpm to obtain an aerogel composite.

9. The foamed thermal insulation material according to claim 8, characterized in that: The mass ratio of the fiber A1, the fiber B1, the Al2O3-Y2O3-SiO2 ternary aerogel, the aqueous polyurethane emulsion and the deionized water is: 1:1:(5.5-8.3):(3.6-6.5):

12.

10. A method for preparing a foamed thermal insulation material according to any one of claims 1 to 9, characterized in that: The following steps are involved: Ingredients: weigh each component according to the preset target ratio and set aside Primary slurry preparation: 1 / 2 part by weight of silicate cement, 1 / 2 part by weight of waterborne polyurethane emulsion, 2 / 3 part by weight of filler and appropriate amount of water are put into a mixer, and stirred at room temperature and a stirring frequency of 1800 rpm for 10 minutes to obtain slurry A; Secondary slurry mixing: prepare the remaining amount of silicate cement, the remaining amount of waterborne polyurethane emulsion, the remaining amount of filler, aerogel composite, dispersant and the remaining amount of water, put them into a mixer, stir them at room temperature and a stirring frequency of 1800 rpm for 20 minutes, and then obtain slurry B; Finished product mixing: Before use, put slurry A and slurry B into a mixer in sequence, and stir for 15 minutes at 50°C and a stirring frequency of 1200 rpm to obtain the finished foam insulation material.

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